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Mexican America - Introduction
"Mexican America" is a sampling of objects from the collections of the National Museum of American History. The stories behind these objects reflect the history of the Mexican presence in the United States. They illustrate a fundamentally American story about the centuries-old encounter between distinct (yet sometimes overlapping) communities that have coexisted but also clashed over land, culture, and livelihood.
Who, where, and what is Mexico? Over time, the definitions and boundaries of Mexico have changed. The Aztec Empire and the area where Náhautl was spoken—today the region surrounding modern Mexico City—was known as Mexico. For 300 years, the Spanish colonizers renamed it New Spain.
When Mexico was reborn in 1821 as a sovereign nation, its borders stretched from California to Guatemala. It was a huge and ancient land of ethnically, linguistically, and economically diverse regions that struggled for national unity. Texas, (then part of the Mexican state of Coahuila y Tejas) was a frontier region far from the dense cities and fertile valleys of central Mexico, a place where immigrants were recruited from the United States. The immigrants in turn declared the Mexican territory an independent republic in 1836 (later a U.S. state), making the state the first cauldron of Mexican American culture. By 1853, the government of Mexico, the weaker neighbor of an expansionist United States, had lost what are today the states of California, Nevada, Utah, Arizona, New Mexico, Texas, and parts of Colorado and Wyoming. In spite of the imposition of a new border, the historical and living presence of Spaniards, Mexicans, indigenous peoples, and their mixed descendants remained a defining force in the creation of the American West.
“La América Mexicana” es una muestra conformada por objetos provenientes de las distintas colecciones del Museo Nacional de Historia Americana. Estos objetos reflejan la historia de la presencia mexicana en los Estados Unidos e ilustran una crónica fundamentalmente americana acerca del encuentro centenario entre comunidades diferentes que han coexistido, pero que también se han enfrentado, en la pugna por la tierra, la cultura y el sustento.
¿Quién, dónde y qué es México? Con el transcurso del tiempo, las definiciones y los límites de México han ido cambiando. Se conocía como México al Imperio Azteca y toda el área donde se hablaba náhuatl —actualmente la región circundante a la ciudad de México. Durante 300 años los colonizadores españoles se refirieron a ella como Nueva España. Cuando en 1821 México resurgió como una nación soberana, sus fronteras se extendían desde California a Guatemala. En ese entonces era un antiguo e inmenso territorio conformado por regiones étnica, lingüística y económicamente diversas que luchaban por adquirir unidad nacional. Texas (en ese entonces parte de los estados mexicanos de Coahuila y Tejas) era una región fronteriza lejos de las densas urbes y de los fértiles valles de México central, donde se reclutaban inmigrantes de los Estados Unidos. En el año 1836 este territorio mexicano se declaró como república independiente (y más tarde, estado de EE.UU.), convirtiéndose en el primer calderón de la cultura mexicoamericana. Hacia 1853, el gobierno de México, el vecino débil de un Estados Unidos en expansión, había perdido el territorio de los actuales estados de California, Nevada, Utah, Arizona, Nuevo México, Texas y partes de Colorado y Wyoming. A pesar de la imposición de un nuevo límite fronterizo, la presencia histórica y ocupacional de los españoles, mexicanos y pueblos indígenas, junto a sus descendientes mestizos, constituiría a lo largo del tiempo una influencia determinante para el desarrollo del Oeste Americano.
"Mexican America - Introduction" showing 1 items.
- This print depicts American forces attacking the fortress palace of Chapultepec on Sept. 13th, 1847. General Winfield Scott, in the lower left on a white horse, led the southern division of the U.S. Army that successfully captured Mexico City during the Mexican American War. The outcome of American victory was the loss of Mexico's northern territories, from California to New Mexico, by the terms set in the Treaty of Guadalupe Hidalgo. It should be noted that the two countries ratified different versions of the same peace treaty, with the United States ultimately eliminating provisions for honoring the land titles of its newly absorbed Mexican citizens. Despite notable opposition to the war from Americans like Abraham Lincoln, John Quincy Adams, and Henry David Thoreau, the Mexican-American War proved hugely popular. The United States' victory boosted American patriotism and the country's belief in Manifest Destiny.
- This large chromolithograph was first distributed in 1848 by Nathaniel Currier of Currier and Ives, who served as the "sole agent." The lithographers, Sarony & Major of New York (1846-1857) copied it from a painting by "Walker." Unfortunately, the current location of original painting is unknown, however, when the print was made the original painting was owned by a Captain B. S. Roberts of the Mounted Rifles. The original artist has previously been attributed to William Aiken Walker as well as to Henry A. Walke. William Aiken Walker (ca 1838-1921) of Charleston did indeed do work for Currier and Ives, though not until the 1880's and he would have only have been only 10 years old when this print was copyrighted. Henry Walke (1808/9-1896) was a naval combat artist during the Mexican American War who also worked with Sarony & Major and is best known for his Naval Portfolio.
- Most likely the original painting was done by James Walker (1819-1889) who created the "Battle of Chapultepec" 1857-1862 for the U.S. Capitol. This image differs from the painting commissioned for the U. S. Capitol by depicting the troops in regimented battle lines with General Scott in a more prominent position in the foreground. James Walker was living in Mexico City at the outbreak of the Mexican War and joined the American forces as an interpreter. He was attached to General Worth's staff and was present at the battles of Contreras, Churubusco, and Chapultepec. The original painting's owner, Captain Roberts was assigned General Winfield Scott to assist Walker with recreating the details of the battle of Chapultepec. When the painting was complete, Roberts purchased the painting. By 1848, James Walker had returned to New York and had a studio in New York City in the same neighborhood as the print's distributor Nathaniel Currier as well as the lithographer's Napoleon Sarony and Henry B. Major.
- This popular lithograph was one of several published to visually document the war while engaging the imagination of the public. Created prior to photography, these prints were meant to inform the public, while generally eliminating the portrayal of the more gory details. Historians have been able to use at least some prints of the Mexican War for study and to corroborate with the traditional literary forms of documentation. As an eyewitness, Walker could claim accuracy of detail within the narrative in his painting. The battle is presented in the grand, historic, heroic style with the brutality of war not portrayed. The print depiction is quite large for a chromo of the period. In creating the chromolithographic interpretation of the painting, Sarony & Major used at least four large stones to produce the print "in colours," making the most of their use of color. They also defined each figure with precision by outlining each in black. This print was considered by expert/collector Harry T. Peters as one of the finest ever produced by Sarony & Major.
- Currently not on view
- Date made
- associated date
- Currier, Nathaniel
- Scott, Winfield
- Sarony & Major
- Walker, James
- ID Number
- catalog number
- accession number
- Data Source
- National Museum of American History, Kenneth E. Behring Center | <urn:uuid:ff577d1a-83b8-467c-af1c-4c0aa2ead4fb> | CC-MAIN-2013-20 | http://americanhistory.si.edu/collections/object-groups/mexican-america?edan_start=0&edan_fq=date%3A%221840s%22 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.776227 | 1,938 | 4.0625 | 4 |
Details of Glycemic Index (GI)
The GI Scale
The glycemic index uses a scale from 1 to 100, which indicates the rate at which 50 grams of carbohydrate in a particular food is absorbed into the bloodstream as blood-sugar. The main reference food (rated 100) is glucose.
GI Rating Categories
The glycemic index divides carbohydrate
foods into three categories:
GI Food Testing is Ongoing
Not all foods have been given a GI value, although most food-types are covered. However, due to the way GI is measured using volunteer subjects, results can vary, so GI values for some specific foods are not yet uniformly established.
GI - Diabetes and Weight Control
Although the glycemic index was first designed to assist diabetes patients manage their blood-sugar levels, dietitians and weight experts now use it as a tool to help treat obesity, food cravings and appetite swings, and improve eating habits.
Both the type AND quantity of carbohydrate in our food influence the rise in blood glucose. But the glycemic index only rates a standard 50 gram serving size of digestible carbohydrate in a particular food, which may not be appropriate for all foods. For example, foods whose serving size contains only a small amount of carbohydrate may in practice be better for blood sugar control than foods whose normal serving size contains a large amount of carbs. Therefore, to provide a more meaningful GI-rating system, researchers at Harvard University invented the term Glycemic Load, which applies the glycemic index to normal food serving sizes.
OBESITY, OVERWEIGHT and | <urn:uuid:17b26358-fba0-4434-86b5-ce1458abe71f> | CC-MAIN-2013-20 | http://annecollins.com/gi-food-guide.htm | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.909349 | 321 | 3.75 | 4 |
- published: 19 Mar 2013
- views: 42
- author: T.A. B
possibly testing on weans, that worries me http://www.bbc.co.uk/news/world-us-canada-21849808.
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. The agent stimulates the body's immune system to recognize the agent as foreign, destroy it, and "remember" it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.
Vaccines can be prophylactic (example: to prevent or ameliorate the effects of a future infection by any natural or "wild" pathogen), or therapeutic (e.g. vaccines against cancer are also being investigated; see cancer vaccine).
The term vaccine derives from Edward Jenner's 1796 use of cow pox (Latin variola vaccinia, adapted from the Latin vaccīn-us, from vacca, cow), to inoculate humans, providing them protection against smallpox.
Vaccines do not guarantee complete protection from a disease. Sometimes, this is because the host's immune system simply does not respond adequately or at all. This may be due to a lowered immunity in general (diabetes, steroid use, HIV infection, age) or because the host's immune system does not have a B cell capable of generating antibodies to that antigen.
Even if the host develops antibodies, the human immune system is not perfect and in any case the immune system might still not be able to defeat the infection immediately. In this case, the infection will be less severe and heal faster.
Adjuvants are typically used to boost immune response. Most often aluminium adjuvants are used, but adjuvants like squalene are also used in some vaccines and more vaccines with squalene and phosphate adjuvants are being tested. Larger doses are used in some cases for older people (50–75 years and up), whose immune response to a given vaccine is not as strong.
The efficacy or performance of the vaccine is dependent on a number of factors:
When a vaccinated individual does develop the disease vaccinated against, the disease is likely to be milder than without vaccination.
The following are important considerations in the effectiveness of a vaccination program:
In 1958 there were 763,094 cases of measles and 552 deaths in the United States. With the help of new vaccines, the number of cases dropped to fewer than 150 per year (median of 56). In early 2008, there were 64 suspected cases of measles. 54 out of 64 infections were associated with importation from another country, although only 13% were actually acquired outside of the United States; 63 of these 64 individuals either had never been vaccinated against measles, or were uncertain whether they had been vaccinated.
Vaccines are dead or inactivated organisms or purified products derived from them.
There are several types of vaccines in use. These represent different strategies used to try to reduce risk of illness, while retaining the ability to induce a beneficial immune response.
Some vaccines contain killed, but previously virulent, micro-organisms that have been destroyed with chemicals, heat, radioactivity or antibiotics. Examples are the influenza vaccine, cholera vaccine, bubonic plague vaccine, polio vaccine, hepatitis A vaccine, and rabies vaccine.
Some vaccines contain live, attenuated microorganisms. Many of these are live viruses that have been cultivated under conditions that disable their virulent properties, or which use closely related but less dangerous organisms to produce a broad immune response. Although most attenuated vaccines are viral, some are bacterial in nature. They typically provoke more durable immunological responses and are the preferred type for healthy adults. Examples include the viral diseases yellow fever, measles, rubella, and mumps and the bacterial disease typhoid. The live Mycobacterium tuberculosis vaccine developed by Calmette and Guérin is not made of a contagious strain, but contains a virulently modified strain called "BCG" used to elicit an immune response to the vaccine. The live attenuated vaccine containing strain Yersinia pestis EV is used for plague immunization. Attenuated vaccines have some advantages and disadvantages. They have the capacity of transient growth so they give prolonged protection, and no booster dose is required. But they may get reverted to the virulent form and cause the disease.
Toxoid vaccines are made from inactivated toxic compounds that cause illness rather than the micro-organism. Examples of toxoid-based vaccines include tetanus and diphtheria. Toxoid vaccines are known for their efficacy. Not all toxoids are for micro-organisms; for example, Crotalus atrox toxoid is used to vaccinate dogs against rattlesnake bites.
Protein subunit – rather than introducing an inactivated or attenuated micro-organism to an immune system (which would constitute a "whole-agent" vaccine), a fragment of it can create an immune response. Examples include the subunit vaccine against Hepatitis B virus that is composed of only the surface proteins of the virus (previously extracted from the blood serum of chronically infected patients, but now produced by recombination of the viral genes into yeast), the virus-like particle (VLP) vaccine against human papillomavirus (HPV) that is composed of the viral major capsid protein, and the hemagglutinin and neuraminidase subunits of the influenza virus. Subunit vaccine is being used for plague immunization.
Conjugate – certain bacteria have polysaccharide outer coats that are poorly immunogenic. By linking these outer coats to proteins (e.g. toxins), the immune system can be led to recognize the polysaccharide as if it were a protein antigen. This approach is used in the Haemophilus influenzae type B vaccine.
A number of innovative vaccines are also in development and in use:
While most vaccines are created using inactivated or attenuated compounds from micro-organisms, synthetic vaccines are composed mainly or wholly of synthetic peptides, carbohydrates or antigens.
Vaccines may be monovalent (also called univalent) or multivalent (also called polyvalent). A monovalent vaccine is designed to immunize against a single antigen or single microorganism. A multivalent or polyvalent vaccine is designed to immunize against two or more strains of the same microorganism, or against two or more microorganisms. In certain cases a monovalent vaccine may be preferable for rapidly developing a strong immune response.
The immune system recognizes vaccine agents as foreign, destroys them, and "remembers" them. When the virulent version of an agent comes along the body recognizes the protein coat on the virus, and thus is prepared to respond, by (1) neutralizing the target agent before it can enter cells, and (2) by recognizing and destroying infected cells before that agent can multiply to vast numbers.
When two or more vaccines are mixed together in the same formulation, the two vaccines can interfere. This most frequently occurs with live attenuated vaccines, where one of the vaccine components is more robust than the others and suppresses the growth and immune response to the other components. This phenomenon was first noted in the trivalent Sabin polio vaccine, where the amount of serotype 2 virus in the vaccine had to be reduced to stop it from interfering with the "take" of the serotype 1 and 3 viruses in the vaccine. This phenomenon has also been found to be a problem with the dengue vaccines currently being researched,[when?] where the DEN-3 serotype was found to predominate and suppress the response to DEN-1, -2 and -4 serotypes.
Vaccines have contributed to the eradication of smallpox, one of the most contagious and deadly diseases known to man. Other diseases such as rubella, polio, measles, mumps, chickenpox, and typhoid are nowhere near as common as they were a hundred years ago. As long as the vast majority of people are vaccinated, it is much more difficult for an outbreak of disease to occur, let alone spread. This effect is called herd immunity. Polio, which is transmitted only between humans, is targeted by an extensive eradication campaign that has seen endemic polio restricted to only parts of four countries (Afghanistan, India, Nigeria and Pakistan). The difficulty of reaching all children as well as cultural misunderstandings, however, have caused the anticipated eradication date to be missed several times.
In order to provide best protection, children are recommended to receive vaccinations as soon as their immune systems are sufficiently developed to respond to particular vaccines, with additional "booster" shots often required to achieve "full immunity". This has led to the development of complex vaccination schedules. In the United States, the Advisory Committee on Immunization Practices, which recommends schedule additions for the Centers for Disease Control and Prevention, recommends routine vaccination of children against: hepatitis A, hepatitis B, polio, mumps, measles, rubella, diphtheria, pertussis, tetanus, HiB, chickenpox, rotavirus, influenza, meningococcal disease and pneumonia. The large number of vaccines and boosters recommended (up to 24 injections by age two) has led to problems with achieving full compliance. In order to combat declining compliance rates, various notification systems have been instituted and a number of combination injections are now marketed (e.g., Pneumococcal conjugate vaccine and MMRV vaccine), which provide protection against multiple diseases.
Besides recommendations for infant vaccinations and boosters, many specific vaccines are recommended at other ages or for repeated injections throughout life—most commonly for measles, tetanus, influenza, and pneumonia. Pregnant women are often screened for continued resistance to rubella. The human papillomavirus vaccine is recommended in the U.S. (as of 2011) and UK (as of 2009). Vaccine recommendations for the elderly concentrate on pneumonia and influenza, which are more deadly to that group. In 2006, a vaccine was introduced against shingles, a disease caused by the chickenpox virus, which usually affects the elderly.
Sometime during the 1770s Edward Jenner heard a milkmaid boast that she would never have the often-fatal or disfiguring disease smallpox, because she had already had cowpox, which has a very mild effect in humans. In 1796, Jenner took pus from the hand of a milkmaid with cowpox, inoculated an 8-year-old boy with it, and six weeks later variolated the boy's arm with smallpox, afterwards observing that the boy did not catch smallpox. Further experimentation demonstrated the efficacy of the procedure on an infant. Since vaccination with cowpox was much safer than smallpox inoculation, the latter, though still widely practiced in England, was banned in 1840. Louis Pasteur generalized Jenner's idea by developing what he called a rabies vaccine, and in the nineteenth century vaccines were considered a matter of national prestige, and compulsory vaccination laws were passed.
The twentieth century saw the introduction of several successful vaccines, including those against diphtheria, measles, mumps, and rubella. Major achievements included the development of the polio vaccine in the 1950s and the eradication of smallpox during the 1960s and 1970s. Maurice Hilleman was the most prolific of the developers of the vaccines in the twentieth century. As vaccines became more common, many people began taking them for granted. However, vaccines remain elusive for many important diseases, including malaria and HIV.
||The neutrality of this section is disputed. Please see the discussion on the talk page. Please do not remove this message until the dispute is resolved. (October 2011)|
||This article is missing information about Scientific rebuttal to the attacks. This concern has been noted on the talk page where whether or not to include such information may be discussed. (October 2011)|
Opposition to vaccination, from a wide array of vaccine critics, has existed since the earliest vaccination campaigns. Although the benefits of preventing suffering and death from serious infectious diseases greatly outweigh the risks of rare adverse effects following immunization, disputes have arisen over the morality, ethics, effectiveness, and safety of vaccination. Some vaccination critics say that vaccines are ineffective against disease or that vaccine safety studies are inadequate. Some religious groups do not allow vaccination, and some political groups oppose mandatory vaccination on the grounds of individual liberty. In response, concern has been raised that spreading unfounded information about the medical risks of vaccines increases rates of life-threatening infections, not only in the children whose parents refused vaccinations, but also in other children, perhaps too young for vaccines, who could contract infections from unvaccinated carriers (see herd immunity).
One challenge in vaccine development is economic: many of the diseases most demanding a vaccine, including HIV, malaria and tuberculosis, exist principally in poor countries. Pharmaceutical firms and biotechnology companies have little incentive to develop vaccines for these diseases, because there is little revenue potential. Even in more affluent countries, financial returns are usually minimal and the financial and other risks are great.
Most vaccine development to date has relied on "push" funding by government, universities and non-profit organizations. Many vaccines have been highly cost effective and beneficial for public health. The number of vaccines actually administered has risen dramatically in recent decades.[when?] This increase, particularly in the number of different vaccines administered to children before entry into schools may be due to government mandates and support, rather than economic incentive.
The filing of patents on vaccine development processes can also be viewed as an obstacle to the development of new vaccines. Because of the weak protection offered through a patent on the final product, the protection of the innovation regarding vaccines is often made through the patent of processes used on the development of new vaccines as well as the protection of secrecy.
Vaccine production has several stages. First, the antigen itself is generated. Viruses are grown either on primary cells such as chicken eggs (e.g., for influenza), or on continuous cell lines such as cultured human cells (e.g., for hepatitis A). Bacteria are grown in bioreactors (e.g., Haemophilus influenzae type b). Alternatively, a recombinant protein derived from the viruses or bacteria can be generated in yeast, bacteria, or cell cultures. After the antigen is generated, it is isolated from the cells used to generate it. A virus may need to be inactivated, possibly with no further purification required. Recombinant proteins need many operations involving ultrafiltration and column chromatography. Finally, the vaccine is formulated by adding adjuvant, stabilizers, and preservatives as needed. The adjuvant enhances the immune response of the antigen, stabilizers increase the storage life, and preservatives allow the use of multidose vials. Combination vaccines are harder to develop and produce, because of potential incompatibilities and interactions among the antigens and other ingredients involved.
Vaccine production techniques are evolving. Cultured mammalian cells are expected to become increasingly important, compared to conventional options such as chicken eggs, due to greater productivity and low incidence of problems with contamination. Recombination technology that produces genetically detoxified vaccine is expected to grow in popularity for the production of bacterial vaccines that use toxoids. Combination vaccines are expected to reduce the quantities of antigens they contain, and thereby decrease undesirable interactions, by using pathogen-associated molecular patterns.
In 2010, India produced 60 percent of world's vaccine worth about $900 million.
Many vaccines need preservatives to prevent serious adverse effects such as Staphylococcus infection that, in one 1928 incident, killed 12 of 21 children inoculated with a diphtheria vaccine that lacked a preservative. Several preservatives are available, including thiomersal, phenoxyethanol, and formaldehyde. Thiomersal is more effective against bacteria, has better shelf life, and improves vaccine stability, potency, and safety, but in the U.S., the European Union, and a few other affluent countries, it is no longer used as a preservative in childhood vaccines, as a precautionary measure due to its mercury content. Although controversial claims have been made that thiomersal contributes to autism, no convincing scientific evidence supports these claims.
There are several new delivery systems in development[when?] that will hopefully make vaccines more efficient to deliver. Possible methods include liposomes and ISCOM (immune stimulating complex).
The latest developments[when?] in vaccine delivery technologies have resulted in oral vaccines. A polio vaccine was developed and tested by volunteer vaccinations with no formal training; the results were positive in that the ease of the vaccines increased. With an oral vaccine, there is no risk of blood contamination. Oral vaccines are likely to be solid which have proven to be more stable and less likely to freeze; this stability reduces the need for a "cold chain": the resources required to keep vaccines within a restricted temperature range from the manufacturing stage to the point of administration, which, in turn, may decrease costs of vaccines. A microneedle approach, which is still in stages of development, uses "pointed projections fabricated into arrays that can create vaccine delivery pathways through the skin".
A nanopatch is a needle free vaccine delivery system which is under development. A stamp-sized patch similar to an adhesive bandage contains about 20,000 microscopic projections per square inch. When worn on the skin, it will deliver vaccine directly to the skin, which has a higher concentration of immune cells than that in the muscles, where needles and syringes deliver. It thus increases the effectiveness of the vaccination using a lower amount of vaccine used in traditional syringe delivery system.
The use of plasmids has been validated in preclinical studies as a protective vaccine strategy for cancer and infectious diseases. However, in human studies this approach has failed to provide clinically relevant benefit. The overall efficacy of plasmid DNA immunization depends on increasing the plasmid's immunogenicity while also correcting for factors involved in the specific activation of immune effector cells.
Vaccinations of animals are used both to prevent their contracting diseases and to prevent transmission of disease to humans. Both animals kept as pets and animals raised as livestock are routinely vaccinated. In some instances, wild populations may be vaccinated. This is sometimes accomplished with vaccine-laced food spread in a disease-prone area and has been used to attempt to control rabies in raccoons.
Where rabies occurs, rabies vaccination of dogs may be required by law. Other canine vaccines include canine distemper, canine parvovirus, infectious canine hepatitis, adenovirus-2, leptospirosis, bordatella, canine parainfluenza virus, and Lyme disease among others.
Vaccine development has several trends:
Principles that govern the immune response can now be used in tailor-made vaccines against many noninfectious human diseases, such as cancers and autoimmune disorders. For example, the experimental vaccine CYT006-AngQb has been investigated as a possible treatment for high blood pressure. Factors that have impact on the trends of vaccine development include progress in translatory medicine, demographics, regulatory science, political, cultural, and social responses.
|Modern Vaccine and Adjuvant Production and Characterization, Genetic Engineering & Biotechnology News|
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The bacterium Micavibrio aeruginosavorus (yellow), leeching
on a Pseudomonas aeruginosa bacterium (purple).
What’s the news: If bacteria had blood, the predatory microbe Micavibrio aeruginosavorus would essentially be a vampire: it subsists by hunting down other bugs, attaching to them, and sucking their life out. For the first time, researchers have sequenced the genome of this strange microorganism, which was first identified decades ago in sewage water. The sequence will help better understand the unique bacterium, which has potential to be used as a “living antibiotic” due to its ability to attack drug-resistant biofilms and its apparent fondness for dining on pathogens.
Anatomy of a Vampire:
- The bacterium has an interesting multi-stage life history. During its migratory phase it sprouts a single flagellum and goes hunting for prey. Once it find a delectable morsel of bacterium, it attacks and irreversibly attaches to the surface, and sucks out all of the good stuff: carbohydrates, amino acids, proteins, DNA, etc.
- Sated, the cell divides in two via binary fission, and the now-depleted host is left for dead.
Hungry for Pathogens:
- M. aeruginosavorus cannot be grown by itself; it must be cultured along with another bacteria to feed upon. A 2006 study found that it only grew upon three bacterial species, all of which can cause pneumonia-like disease in humans. A more recent study showed that it can prey upon a wider variety of microbes, most of them potentially pathogenic, like E. coli.
- These studies also found that M. aeruginosavorus has a knack for disrupting biofilms, the dense collection of bacteria that cause harmful plaques on teeth and medical implants alike, and can be up to 1,000 more resistant to antibiotics than free-swimming bugs.
- The bacteria can also swim through viscous fluids like mucous and kills Pseudomonas aeruginosa, the bacterium that can colonize lungs of cystic fibrosis patients and form a glue-like film.
- These qualities have caught the eye of researchers who think it could be used as a living antibiotic to treat biofilms and various types of drug-resistant bacteria, which are a growing problem in medicine. Sequencing the organism’s genome is an important step in understanding its biochemistry and how it preys on other microbes.
Clues From the Vampire Code:
- The new study found that each phase of life involves the use (or expression) of different sets of genes. The migratory/hunting phase involves many segments that code for flagellum formation and genes involved in quorum sensing. The attachment phase involves a wide variety of secreted chemicals and enzymes that facilitate the flow of materials from the host.
- Micavibrio aeruginosavorus possesses no genes for amino acid transporters, a rather rare trait only seen in a few other bacterial species that depend heavily upon their host to help them shuttle these vital protein building-blocks. This absence helps explain the bacterium’s dependence on a narrow range of prey, from which it directly steals amino acids. Although it remains unclear exactly how the microbe attaches to and infiltrates other cells.
The Future Holds:
- The range of microbes upon which Micavibrio aeruginosavorus can survive is expanding; after being kept in laboratory conditions for years it has apparently evolved a more diverse diet. If this expansion continues, that could be a real problem for its use as an antibiotic; it could begin to eat beneficial gut bacteria, for example.
- Researchers claim it is harmless to friendly gut microbes, but it hasn’t been tested on all the varieties of bacteria present in humans.
- Several important steps must be taken before testing in people, like learning more about what traits makes another bacteria tasty to Micavibrio aeruginosavorus. Researchers speculate the bacterium may need to be genetically altered in order to go after specific pathogens, or to reduce the risk of it causing unforeseen complications.
Reference: Zhang Wang, Daniel E Kadouri, Martin Wu. Genomic insights into an obligate epibiotic bacterial predator: Micavibrio aeruginosavorus ARL-13. BMC Genomics, 2011; 12 (1): 453 DOI: 10.1186/1471-2164-12-453
Image credit: University of Virginia | <urn:uuid:d904d662-9bf2-45c5-84ed-06cf69edb907> | CC-MAIN-2013-20 | http://blogs.discovermagazine.com/80beats/?p=33049 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.915806 | 954 | 3.921875 | 4 |
died Aug. 28, 1818, St. Charles, Mo., U.S.
black pioneer trader and founder of the settlement that later became the city of Chicago.
Du Sable, whose French father had moved to Haiti and married a black woman there, is believed to have been a freeborn. At some time in the 1770s he went to the Great Lakes area of North America, settling on the shore of Lake Michigan at the mouth of the Chicago River, with his Potawatomi wife, Kittihawa (Catherine). His loyalty to the French and the Americans led to his arrest in 1779 by the British, who took him to Fort Mackinac. From 1780 to 1783 or 1784 he managed for his captors a trading post called the Pinery on the St. Clair River in present-day Michigan, after which he returned to the site of Chicago. By 1790 Du Sable's establishment there had become an important link in the region's fur and grain trade.
In 1800 he sold out and moved to Missouri, where he continued as a farmer and trader until his death. But his 20-year residence on the shores of Lake Michigan had established his title as Father of Chicago. | <urn:uuid:c7c44bd1-3600-48a9-b33a-acfce3aaa2c0> | CC-MAIN-2013-20 | http://britannica.com/blackhistory/article-9031305 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.990193 | 252 | 3.65625 | 4 |
Instructors: Andrea Dykstra, Curt Van Dam, Kelli Ten Haken and Tami De Jong
1. Students will gain interest in the Unit on Alaska.
2. Students will be introduced to Alaska and the Iditarod race that takes place
in Alaska every year.
3. Students will be able to appreciate the beauty of Godís creation in Alaska.
4. Students will be able to see Godís majesty and power in their personal experiences.
In this lesson, the students will discuss what they know about Alaska. They will watch
a movie and then discuss how God shows His power and majesty through creation. Next,
they will be introduced to the Iditarod race by reading a story and then the teachers will
explain the game the students will play about the Iditarod through the unit. At the end of
class, students will have a chance to start work on their maps of Alaska and then the
teachers will end in closing prayer.
- Psalm 19:1-
The Heavens declare the glory of God; the skies proclaim the work of His hands.
- Other Scripture references that can be used through out the unit:
The Creation story in Gen. 1 and 2
Alaska: Spirit of the Wild
2. DVD player
5. Learning center and trade books
6. Example of the Iditarod Game
7. Book: Iditarod Dream by Ted Wood
8. Overhead projector, overhead and pen
9. Construction paper
10. Markers, crayons, colored pencils
1. On the first day of this unit, teachers should enter the room dressed in parkas,
snowshoes, scarves, mittens; anything that looks like what people in Alaska would
wear. Motion for the student to sit down. Once they are quiet, ask them where
they think the teachers are from and how they came to this conclusion. We would
expect conclusions such as the Artic, Antarctica, and possibly Alaska.
2. Have students take out a sheet of paper and write five things down that come to
their minds when they think of Alaska. Have them get into groups of three and
share what they wrote with their group. The students will be encouraged to share
the combined ideas from their group with the whole class. The teacher will write
down these ideas on the overhead.
3. Explain to the students that they are going to be learning about all of these of
these things and even more about Alaska in the upcoming unit.
4. Have each student write down one or two things about Alaska they would like
to know more about. Suggest ideas such as: What sports do they play in Alaska?
How many people live there? Is it really cold and snowy year round? Take these
ideas into consideration when planning the rest of the unit.
1. Put in the DVD Alaska: Sprit of the Wild. Students will watch the movie. It is forty
minutes long. Before they watch it, share with them the beauty that can be found in
Alaska. Tell them to look specifically for how they can see God in the things that are
shown on the film.
2. After the movie, discuss with the students what they thought of the movie. Ask them
questions such as what surprised you about this film? What did you learn about Alaska
that you didnít know before? What can we discover about God by watching this movie?
How can we get to know God better by studying Alaska?
3. Read Psalm 19:1 aloud. Read it again, this time have the students say it after you. Ask
them how this verse relates to Alaska. Hopefully they will make the connection that
creation shouts Godís praise. Alaska is so beautiful; this reflects on Godís majesty,
creativity and mercy. God loves us enough to give us beautiful creation simply so we
can enjoy it. We can see his fingerprints in Alaska.
4. Read Psalm 8 aloud. Again, ask them how this verse relates to Alaska. They will probably
have similar responses as above in step three. Share a personal experience of how he/
she has seen Godís power and majesty in His creation.
- For example, this is my own experience; you could share something similar to it:
One time I climbed the highpoint of Colorado with my dad. We started hiking
before the sun was up. As we were walking along the ridge of the mountain, the
sun began to rise; the colors were brilliant! We kept on hiking and hiking. I was
getting tired and hungry but soon we came close to the top. As I climbed up the
last little peak and the top of the mountain, I looked out and the view was
breathtaking!!! I had never seen so many snow capped mountains before. Sitting
up there on the mountaintop, I felt such a joy and peace. What a great God I
serve! He created all of this; His creation alone is enough to tell of His majesty.
5. Ask the students if any of them have had an experience like this; encourage them to
share if they would like.
6. Encourage them to find other verses that could relate to our study of Alaska and bring
them to class tomorrow to share.
1. Introduce the Iditarod race the studentís will be learning about by reading the book
Iditarod Dream by Ted Wood. As you are reading, stop periodically through out the
book and ask them to jot down a few of their thoughts. At the end of the book ask
them to share a few thoughts they wrote down about the book.
2. Introduce the game the students will be playing throughout the unit. Tell the students
they will be having their own Iditarod race in the classroom. Each student will make a
map of Alaska on construction paper. On this map, they will draw the trail of the
Iditarod race. They will have to map out the different checkpoints of the race on their
trails. It is their job to find out how many miles are between each checkpoint and how
many miles they can travel in one day.
3. Each day the students will move their markers on their maps how ever many miles we
decide as a class they can travel in one day. Every morning the students will receive
a ďracerís fateĒ card. These cards will say various things such as, ďyour dog has broken
a leg, move back twenty milesĒ, or ď you have found an extra bundle of food on the trail,
move ahead twelve milesĒ. The students will have to keep track of where they are on
the trail on their own maps and on a large map on the classroom bulletin board.
4. Each afternoon, students will have an opportunity to receive another card if they got
their homework done on time that day. This card could be good or bad, but the students
get to decide if they want to take it.
5. This activity will be incorporated into language arts. The students will be keeping a
race journal. As they play this game they can write their feelings about the race in the
journal as if they were an actual racer.
6. This game will also be incorporated into math. Students will need to do calculations to
play the game correctly. They will also discover how to find median, mean and
using the game.
1. The students will begin making their maps of Alaska for the Iditarod game. The
outline of the map of Alaska will be projected on the overhead so the students have
something to follow when they draw. Copies of the outline of this map will be available
for students to trace if they do not want to draw the map freehand.
2. The students can use crayons or colored pencils to make their maps on.
3. The trail outline and check points will be labeled on the overhead map, but the students
will need to research how many miles are in between each check point in a later class
1. Read Psalm 8 one more time and end in prayer, thanking God for His creativity that
is evident in all of creation, especially as it has been seen in Alaska today.
1. Students can do more research about the real Iditarod race on the Internet.
2. Students can read one of the many books about Alaska set up in the learning center.
3. Students can complete any activity set up in the learning center, including: math
story problems, language arts writing activities, and social studies and science
1. Observe how much students participate in the lesson. Have one teacher walk
around with a checklist and put checks by the names of the students who are
on task and participating by sharing, asking questions, diligently listening.
2. Observe how diligently students work on their maps. Check the next day to see
if they have completed them. Give them a check if they are finished and are done
Lesson Plans Unit Outline Home Page
Trade Books Learning Center | <urn:uuid:d07cc3a6-5c93-4a54-aa41-e4364927c35f> | CC-MAIN-2013-20 | http://center.dordt.edu/266.543units/Alaska%20unit/intro.les.html | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.949955 | 1,899 | 3.671875 | 4 |
Tornadoes are the most intense storms on the planet, and they’re never discussed without at least some mention of the term wind shear. Many of us sitting at home, though, have no idea what wind shear is, or if we do, how it affects tornado production.
What is Wind Shear
Wind shear, although it might sound complex, is a simple concept. Wind shear is merely the change in wind with height, in terms of wind direction and speed. I think that we all understand that the wind is generally stronger in the atmosphere over our heads than it is here on the ground, and if we think of the atmosphere in terms of the three dimensions that it has, it should not be surprising that the wind above us might also be blowing from a different direction than the wind at the ground. When that happens–the wind speed and direction vary with height–wind shear is occurring.
Wind Shear and Supercell Thunderstorms
This wind shear is an important part of the process in the development of a supercell thunderstorm, from which the vast majority of strong tornadoes form.
All thunderstorms are produced by a powerful updraft–a surge of air that rises from the ground into the upper levels of the atmosphere, and when this updraft forms in an area where wind shear is present, the updraft is influence by this speed and different direction of the wind above, pushing the column of air in the updraft into a more vertical alignment.
Rain’s Influence on Tornado Production
Needless to say, thunderstorms typically produce very heavy rain, and rain-cooled air is much heavier than the warm air of the updraft, so the rain-cooled air, produces a compensating downdraft (what comes up, must come down). This downdraft pushes the part of the rotating air that was forced in its direction by the stronger wind aloft downward, and the result is a horizontal column of rotating air.
That’s Not a Tornado!
I know what you’re thinking that you’ve seen enough TLC or Discovery Channel shows to know that a horizontal column of air is NOT a tornado; you need a vertical column of air.
This Can Be a Tornado
You’re right, but remember the updraft that is driving the thunderstorm is still working, and it’s able to pull the horizontal, spinning column of air into the thunderstorm, resulting in a vertical column of spinning air.
(NOAA image showing vertical column of air in a supercell thunderstorm)
The result is a rotating thunderstorm capable of producing a tornado, and it would not be possible without wind shear.
(NOAA image showing tornado formation in supercell thunderstorm) | <urn:uuid:7400301c-e625-46d5-be90-1020cf8d52f8> | CC-MAIN-2013-20 | http://cloudyandcool.com/2009/05/05/wind-shear-and-tornadoes/ | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.916764 | 573 | 4.15625 | 4 |
Is this bone a Neanderthal flute?
Cave Bear femur fragment from Slovenia, 43+kya
DOUBTS AIRED OVER NEANDERTHAL BONE 'FLUTE'
(AND REPLY BY MUSICOLOGIST BOB FINK)
Science News 153 (April 4, 1998): 215.
By B. Bower
Amid much media fanfare, a research team in 1996 trumpeted an ancient, hollowed out bear bone pierced on one side with four complete or partial holes as the earliest known musical instrument. The perforated bone, found in an Eastern European cave, represents a flute made and played by Neandertals at least 43,000 ye us ago, the scientists contended.
Now it's time to stop the music, say two archaeologists who examined the purported flute last spring. On closer inspection, the bone appears to have been punctured and gnawed by the teeth of an animal -- perhaps a wolf -- as it stripped the limb of meat and marrow report, April Nowell and Philip G. Chase, both of the University of Pennsylvania in Philadelphia. "The bone was heavily chewed by one or more carnivores, creating holes that became more rounded due to natural processes after burial," Nowell says. "It provides very weak evidence for the origins of [Stone Age] music." Nowell presented the new analysis at the annual meeting of the Paleoanthropology Society in Seattle last week.
Nowell and Chase examined the bone with the permission of its discoverer, Ivan Turk of the Slovenian Academy of Sciences in Ljubljana (S.N.: 11/23/96, p. 328). Turk knows of their conclusion but still views the specimen as a flute.
Both open ends of the thighbone contain clear signs of gnawing by carnivores, Nowell asserts. Wolves and other animals typically bite off nutrient-rich tissue at the ends of limb bones and extract available marrow. If Neandertals had hollowed out the bone and fashioned holes in it, animals would not have bothered to gnaw it, she says.
Complete and partial holes on the bone's shaft were also made by carnivores, says Nowell. Carnivores typically break open bones with their scissor like cheek teeth. Uneven bone thickness and signs of wear along the borders of the holes, products of extended burial in the soil, indicate that openings made by cheek teeth were at first less rounded and slightly smaller, the researchers hold.
Moreover, the simultaneous pressure of an upper and lower tooth produced a set of opposing holes, one partial and one complete, they maintain.
Prehistoric, carnivore-chewed bear bones in two Spanish caves display circular punctures aligned in much the same way as those on the Slovenian find. In the March Antiquity, Francesco d'Errico of the Institute of Quaternary Prehistory and Geology in Talence, France, and his colleagues describe the Spanish bones.
In a different twist, Bob Fink, an independent musicologist in Canada, has reported
on the Internet
(http://www.webster.sk.ca/greenwich/fl-compl.htm) that the spacing of the two complete and two partial holes on the back of the Slovenian bone conforms to musical notes on the diatonic (do, re, mi. . .) scale.
The bone is too short to incorporate the diatonic scale's seven notes, counter Nowell and Chase. Working with Pennsylvania musicologist Robert Judd, they estimate that the find's 5.7-inch length is less than half that needed to cover the diatonic spectrum. The recent meeting presentation is "a most convincing analysis," comments J. Desmond Clark of the University of California, Berkeley, although it's possible that Neandertals blew single notes through carnivore-chewed holes in the bone.
"We can't exclude that possibility," Nowell responds. "But it's a big leap of faith to conclude that this was an intentionally constructed flute."
TO THE EDITOR, SCIENCE NEWS (REPLY BY BOB FINK, May 1998)
(See an update of this discussion on Bob Fink's web site, November 2000)
The doubts raised by Nowell and Chase (April 4th, DOUBTS AIRED OVER NEANDERTHAL BONE 'FLUTE') saying the Neanderthal Bone is not a flute have these weaknesses:
The alignment of the holes -- all in a row, and all of equivalent diameter, appear to be contrary to most teeth marks, unless some holes were made independently by several animals. The latter case boggles the odds for the holes ending up being in line. It also would be strange that animals homed in on this one bone in a cave full of bones, where no reports of similarly chewed bones have been made.
This claim is harder to believe when it is calculated that chances for holes to
be arranged, by chance, in a pattern that matches the spacings of 4 notes of a
diatonic flute, are only one in hundreds to occur .
The analysis I made on the Internet (http://www.webster.sk.ca/greenwich/fl-compl.htm) regarding the bone being capable of matching 4 notes of the do, re, mi (diatonic) scale included the possibility that the bone was extended with another bone "mouthpiece" sufficiently long to make the notes sound fairly in tune. While Nowell says "it's a big leap of faith to conclude that this was an intentionally constructed flute," it's a bigger leap of faith to accept the immense coincidence that animals blindly created a hole-spacing pattern with holes all in line (in what clearly looks like so many other known bone flutes which are made to play notes in a step-wise scale) and blindly create a pattern that also could play a known acoustic scale if the bone was extended. That's too much coincidence for me to accept. It is more likely that it is an intentionally made flute, although admittedly with only the barest of clues regarding its original condition.
The 5.7 inch figure your article quoted appears erroneous, as the centimeter scale provided by its discoverer, Ivan Turk, indicates the artifact is about 4.3 inches long. However, the unbroken femur would originally have been about 8.5 inches, and the possibility of an additional hole or two exists, to complete a full scale, perhaps aided by the possible thumbhole. However, the full diatonic spectrum is not required as indicated by Nowell and Chase: It could also have been a simpler (but still diatonic) 4 or 5 note scale. Such short-scale flutes are plentiful in homo sapiens history.
Finally, a worn-out or broken flute bone can serve as a scoop for manipulation of food, explaining why animals might chew on its ends later. It is also well-known that dogs chase and maul even sticks, despite their non-nutritional nature. What appears "weak" is not the case for a flute, but the case against it by Nowell and Chase.
Letter to the Editor: Antiquity Journal:
"A Bone to Pick"
By Bob Fink
I have a bone to pick with Francesco d'Errico's viewpoint in the March issue of Antiquity (article too long to reproduce here) regarding the Neanderthal flute found in Slovenia by Ivan Turk. D'Errico argues the bone artifact is not a flute.
D'Errico omits dealing with the best evidence that this bone find is a flute.
Regarding the most important evidence, that of the holes being lined up, neither d'Errico nor Turk make mention of this.
This line-up is remarkable especially if they were made by more than one carnivore, which apparently they'd have to be, based on Turk's analysis of the center-spans of the holes precluding their being made by a single carnivore or bite (Turk,* pp.171-175). To account for this possible difficulty, some doubters do mention "one or more" carnivores (Chase & Nowell, Science News 4/4/98).
My arguments over the past year pointed out the mathematical odds of the lining up of the holes occurring by chance-chewing are too difficult to believe.
The Appendix in my essay ("Neanderthal Flute --A Musicological Analysis") proves that the number of ways a set of 4 random holes could be differently spaced (to produce an audibly different set of tones) are 680 ways. The chances a random set would match the existing fragment's spacing [which also could produce a match to four diatonic notes of the scale] are therefore only one in hundreds. If, in calculating the odds, you also allowed the holes to be out of line, or to be less than 4 holes as well, then the chance of a line-up match is only one from many tens of thousands.
And yet randomness and animal bites still are acceptable to account for holes being in line that could also play some notes of the scale? This is too much coincidence for me to believe occurred by chance.
D'Errico mentions my essay in his article and what he thought it was about, but he overstates my case into being a less believable one. My case simply was that if the bone was long enough (or a shorter bone extended by a mouthpiece insert) then the 4 holes would be consistent and in tune with the sounds of Do, Re, Mi, Fa (or flat Mi, Fa, Sol, and flat La in a minor scale).
In the 5 points I list below, extracted from Turk's monograph in support of this being a flute, d'Errico omits dealing with much of the first, and all of the second, fourth and sixth points.
Turk & Co's monograph shows the presence on site of boring tools, and includes experiments made by Turk's colleague Guiliano Bastiani who successfully produced similar holes in fresh bone using tools of the type found at the site (pp. 176-78 Turk).
They also wrote (pp. 171-75) that:
1. The center-to-center distances of the holes in the artifact are smaller than that of the tooth spans of most carnivores. The smallest tooth spans they found were 45mm, and the holes on the bone are 35mm (or less) apart;
2. Holes bitten are usually at the ends of bones rather than in the center of them;
3. There is an absence of dents, scratches and other signs of gnawing and counter-bites on the artifact;
4. The center-to-center distances do not correspond to the spans of carnivores which could pierce the bone;
5. The diameters of the holes are greater than that producible by a wolf exerting the greatest jaw pressure it had available -- it's doubtful that a wolf's jaws would be strong enough (like a hyena's) to have made the holes, especially in the thickest part of the wall of the artifact.
6. If you accept one or more carnivores, then why did they over-target one bone, when there were so many other bones in the cave site? Only about 4.5% of the juvenile bones were chewed or had holes, according to Turk (p. 117).
* Turk, Ivan (ed.) (1997). Mousterian Bone Flute. Znanstvenoraziskovalni
Center Sazu, Ljubljana, Slovenia.
Maintained by Francis F. Steen, Communication Studies, University of California Los Angeles | <urn:uuid:f166f15d-9976-40ed-8a49-8bed360001ff> | CC-MAIN-2013-20 | http://cogweb.ucla.edu/ep/FluteDebate.html | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.957844 | 2,445 | 3.71875 | 4 |
On this day in 1951, more than six years after the end of World War II in Europe, President Harry S. Truman signed a proclamation officially ending U.S. hostilities with Germany.
The official end to the war came nine years, 10 months and 13 days after Congress had declared war on Nazi Germany. The lawmakers had responded to a declaration of war issued by the Third Reich in the aftermath of the Dec. 7, 1941, Japanese attack on Pearl Harbor and other U.S. bases in the Pacific.
The president explained why he had waited so long after the fighting had ended to act: It had always been America’s hope, Truman wrote, to create a treaty of peace with the government of a united and free Germany, but the postwar policies pursued by the Soviet Union “made it impossible.”
After the war, the United States, Britain, France and the Soviet Union divided Germany into four zones of occupation. Berlin, while located wholly within the Soviet zone, was jointly occupied by the wartime allies and also subdivided into four sectors because of its symbolic importance as the nation’s historic capital and seat of the former Nazi government.
The three western zones were merged to form the Federal Republic of Germany in May 1949, and the Soviets followed suit in October 1949 with the establishment of the German Democratic Republic.
The East German regime began to falter in May 1989, when the removal of Hungary’s border fences punched a hole in the Iron Curtain, allowing tens of thousands of East Germans to flee to the West. Despite the grants of general sovereignty to both German states in 1955, neither of the two German governments held unrestricted sovereignty under international law until after they were reunified in October 1990. | <urn:uuid:802d6d3f-73ff-4476-973b-a3c618ed8f7a> | CC-MAIN-2013-20 | http://dyn.politico.com/printstory.cfm?uuid=5C7F8F2E-EB28-4D2A-84B9-D699AAA47355 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.975901 | 352 | 4.34375 | 4 |
The significance of Alabama Unionists during the Civil War and Reconstruction has long been a subject of study among scholars. Largely centered in northern Alabama and to a lesser degree in the southeast region and in Montgomery and Mobile, Unionists were important both militarily and politically. Until recently, however, the details of this phenomenon have remained less well known, largely because the term Unionist (both then and now) has been used to refer to a range of different individuals and positions.
In the broadest sense, Unionist has meant any white person who opposed secession (including those who later supported the Confederacy) and those who came to support the Union during the war despite having originally supported the Confederacy. This broad definition includes a very wide range of Alabamians—from the most well-to-do planters who ultimately become officers in the Confederate Army to the subsistence farmer who deserted the southern cause midway through the war. It is also possible to define Unionism more narrowly, confining the label to those individuals who resisted both secession and the Confederacy during the war. Such unconditional loyalists probably represented no more than 15 percent of Alabama's adult white population. They were mostly nonslaveholding farmers (though a small minority owned slaves) living in the northern third of the state. A few Unionists also lived in the piney woods and coastal plain further south. In many respects, these men and women were very much like their neighbors who supported the Confederate cause. The reasons they remained loyal to the Union were also quite diverse. Many saw secession as illegal, whereas others felt that it would dishonor the American Revolution and their own ancestors. Still others were certain that secession would end in political or military disaster. Many were influenced by the respected figures in their families or neighborhoods.
Unionism in Alabama arose under the pressures of the presidential election of 1860. Nine months before, the state legislature had directed that, in the event of a Republican's election, a state secession convention would be called. By directly linking the presidential election to secession, the legislature fostered a political atmosphere that was particularly hostile to Unionists. Newspaper editorials and participants at community meetings condemned as traitors those who canvassed for Illinois senator Stephen Douglas, the nominee of the regular Democratic Party, rather than the southern-rights Democratic nominee, John Breckinridge. In the election, fully 80 percent of Alabama's eligible voters participated, giving Breckinridge a substantial victory, with 54 percent of the vote. John Bell, the Constitutional Union candidate who was supported by a number of Alabamians hostile to secession, received 31 percent of the vote. Douglas, the candidate most associated with a strongly Unionist position, polled slightly more than 15 percent. Republican Abraham Lincoln was not even on the ballot in Alabama.
As promised, Alabama secessionists called a convention in the wake of Lincoln's election. The campaign for convention delegates provoked heated and sometimes violent debates among neighbors, forcing many to defend their positions in public. Of the 100 delegates elected, 53 were secessionists and 47 were cooperationists, a term that refers to the delegates' desire to secede only in "cooperation" with other southern states. In fact, the men elected on this platform represented a wide range of ideas about if, when, and under what circumstances to cooperate with secession and included a minority faction—probably less than one-third (the vast majority of them from the northern third of the state)—of unconditional Unionists who opposed secession outright.
These delegates convened in Montgomery on January 7, 1861, and debated secession for four days. On January 11, 1861, the convention passed Alabama's Ordinance of Secession by a vote of 61 to 39. Many of those who voted against the ordinance, however, ultimately did support secession, and four immediately reversed themselves and signed with the majority. Among the opposition, 33 delegates subsequently signed the "Address to the People of Alabama," in which they pledged to consult with their supporters and then act on their wishes. Ten signatories of the address signed the ordinance to satisfy their constituents. Other delegates who rejected the ordinance eventually took active part in the war. Only three signers—Henry C. Sanford of Cherokee County, Elliot P. Jones of Fayette County, and Robert Guttery of Walker County—never signed the ordinance and maintained their Unionism throughout the war. Only two wartime Unionists—R. S. Watkins of Franklin County and Christopher C. Sheats of Winston County—signed neither the "Address" nor the Ordinance of Secession.
Most of the men and women who supported the Union after Alabama's secession faced great difficulties. Many were ostracized and ridiculed by neighbors, called before community vigilance committees for questioning and intimidation, or actually harmed for endorsing the Union. Such treatment was most commonly meted out to those who publicly asserted their views; those who kept quiet and did not interfere with volunteering were often left alone during the first year of the war. After Confederate conscription began in April 1862, however, community tolerance of Unionists waned. Individuals who resisted the draft, for whatever reason, were subject to arrest and imprisonment. Family members who supported resisters were frequently threatened with violence or exile by conscript cavalry who hoped to pressure men to come in from the woods or mountains and surrender. In addition, it was not at all uncommon for the families of Unionists to be targeted for punitive foraging or arson by Confederate forces or local conscript cavalry.
After the Union Army invaded Alabama in early 1862, Unionists had more opportunities to flee behind Union lines for safety and the possibility of employment as soldiers, spies, or laborers. Most well known of Alabama's Union troops was the First Alabama Cavalry, U.S.A., organized in late 1862 by Brig. Gen. Grenville M. Dodge, stationed at Corinth, Mississippi. The regiment served mostly in northern Alabama, western Tennessee, and northeastern Mississippi, though it marched with Gen. William Tecumseh Sherman to Savannah in 1864. Alabama Unionists also joined other federal regiments, particularly those from Tennessee, Indiana, Illinois, and Ohio. Those who remained at home, both within Union-occupied territory and behind Confederate lines, also actively assisted Union forces as spies and guides. In some cases, they collaborated with local African Americans (most often their own slaves) to aid and abet the Union Army or pro-Union men in their neighborhoods. Moreover, African Americans from Alabama also crossed the Union lines to serve as laborers and soldiers, and after the Emancipation Proclamation went into effect in 1863, many were inducted into United States Colored Troops regiments. Almost 5,000 African Americans, or 6 percent of Alabama's black male population between the ages of 18 and 45, volunteered in the Union ranks.
As was the case throughout the South, by the midpoint of the war Alabama's original Unionists were increasingly joined in their dissent by deserters from the Confederate Army, mostly men whose families were struggling at home without their labor. Disillusioned by the realities of warfare, angered by the inequities of service under laws exempting slaveowners and selected professionals, such Alabamians generally wanted the war to end more than they desired Union victory, though some did cross lines and join the Union army rather than desert and avoid service altogether. A small peace movement also emerged at this time among men who had originally opposed secession but later supported the state.
After the war, Unionists continued to struggle politically and socially, for their wartime activities had alienated them from
their now-defeated neighbors. Most eagerly joined the Union League and the Republican Party. Some wartime Unionists helped reintroduce the Methodist-Episcopal Church (as contrasted with the Methodist-Episcopal Church, South) to northern Alabama, finding there a more hospitable environment
for worship. Many campaigned strenuously to convince the president and Congress to limit the political rights of former Confederates.
They also sought positions of local and state authority for others who had supported the Union during the war. At this point,
a number of men who had originally opposed secession but supported the state in 1861, as well as citizens who had become disillusioned
with the war, also moved to the fore of political life in Alabama. These moderates were, in general, encouraged by Pres. Andrew Johnson, who appointed such men to
positions of political authority in the immediate post-war provisional governments he established. The Republican Party in
Alabama was populated by such individuals, as well as core Unionists who had served in the Union Army or otherwise actively
resisted the Confederacy. Both groups were referred to by their Democratic opponents as sc alawags.
Under Congressional Reconstruction (1867-74) wartime loyalists gained greater political power than they had under Presidential Reconstruction, taking leading roles in the constitutional convention of 1867, the Freedmen's Bureau, and the Republican-dominated state legislature. Most also supported, though sometimes reluctantly, voting rights for African Americans as a means to gain political power over former Confederates. For their continued association with northern Republicans and support for African American equality, white Unionists were targeted for intimidation and physical violence by the Ku Klux Klan and other anti-Reconstruction vigilantes. As elsewhere in the South, Alabama Unionists and their Republican allies (white and black, northern and southern) received little in the way of federal assistance to defend against the onslaught of violence. As their party was overwhelmed by the Democratic opposition, Unionists retreated from the forefront of state politics, though those in communities with substantial loyalist populations continued in positions of local political leadership well into the late nineteenth century.
Barney, William L. The Secessionist Impulse: Alabama and Mississippi in 1860. Princeton: Princeton University Press, 1974.
Fitzgerald, Michael W. The Union League Movement in the Deep South: Politics and Agri cultural Change During Reconstruction. Baton Rouge: Louisiana State University Press, 1989.
Mills, Gary B. Southern Loyalists in the Civil War: The Southern Claims Commission. A Composite Directory of Case Files Created by the U.S. Commissioner of Claims, 1871-1880, including those appealed to the War Claims Committee of the U.S. House of Representatives and the U.S. Court of Claims. Baltimore: Genealogical Publishing Company, Inc. 1994.
Rogers, William Warren, Jr. The Confederate Home Front: Montgomery During the Civil War. Tuscaloosa: The University of Alabama Press, 1999.
Storey, Margaret M. Loyalty and Loss: Alabama's Unionists in the Civil War and Reconstruction. Baton Rouge: Louisiana State University Press, 2004.
Margaret M. Storey
Published December 14, 2007
Last updated October 3, 2011 | <urn:uuid:dcf6578e-71df-4e20-904c-5952df38fb9c> | CC-MAIN-2013-20 | http://encyclopediaofalabama.org/face/Article.jsp?id=h-1415 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.973099 | 2,188 | 3.859375 | 4 |
Uveitis is inflammation of the uvea, which is made up of the iris, ciliary body and choroid. Together, these form the middle layer of the eye between the retina and the sclera (white of the eye).
The eye is shaped like a tennis ball, with three different layers of tissue surrounding the central gel-filled cavity, which is called the vitreous. The innermost layer is the retina, which senses light and helps to send images to your brain. The outermost layer is the sclera, the strong white wall of the eye. The middle layer between the sclera and retina is called the uvea.
The uvea contains many blood vessels — the veins, arteries and capillaries — that carry blood to and from the eye. Because the uvea nourishes many important parts of the eye (such as the retina), inflammation of the uvea can damage your sight.
There are several types of uveitis, defined by the part of the eye where it occurs.
- Iritis affects the front of your eye. Also called anterior uveitis, this is the most common type of uveitis. Iritis usually develops suddenly and may last six to eight weeks. Some types of anterior uveitis can be chronic or recurrent.
- If the uvea is inflamed in the middle or intermediate region of the eye, it is called pars planitis (or intermediate uveitis). Episodes of pars planitis can last between a few weeks to years. The disease goes through cycles of getting better, then worse.
- Posterior uveitis affects the back parts of your eye. Posterior uveitis can develop slowly and often lasts for many years.
- Panuveitis occurs when all layers of the uvea are inflamed.
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Basic Use To make a new number, a simple initialization suffices:
var foo = 0; // or whatever number you want
foo = 1; //foo = 1 foo += 2; //foo = 3 (the two gets added on) foo -= 2; //foo = 1 (the two gets removed)
Number literals define the number value. In particular: They appear as a set of digits of varying length. Negative literal numbers have a minus sign before the set of digits. Floating point literal numbers contain one decimal point, and may optionally use the E notation with the character e. An integer literal may be prepended with "0", to indicate that a number is in base-8. (8 and 9 are not octal digits, and if found, cause the integer to be read in the normal base-10). An integer literal may also be found with "0x", to indicate a hexadecimal number. The Math Object Unlike strings, arrays, and dates, the numbers aren't objects. The Math object provides numeric functions and constants as methods and properties. The methods and properties of the Math object are referenced using the dot operator in the usual way, for example:
var varOne = Math.ceil(8.5); var varPi = Math.PI; var sqrt3 = Math.sqrt(3);
Methods random() Generates a pseudo-random number.
var myInt = Math.random();
max(int1, int2) Returns the highest number from the two numbers passed as arguments.
var myInt = Math.max(8, 9); document.write(myInt); //9
min(int1, int2) Returns the lowest number from the two numbers passed as arguments.
var myInt = Math.min(8, 9); document.write(myInt); //8
floor(float) Returns the greatest integer less than the number passed as an argument.
var myInt = Math.floor(90.8); document.write(myInt); //90;
ceil(float) Returns the least integer greater than the number passed as an argument.
var myInt = Math.ceil(90.8); document.write(myInt); //91;
round(float) Returns the closest integer to the number passed as an argument.
var myInt = Math.round(90.8); document.write(myInt); //91; | <urn:uuid:eecdd55e-49d8-40e4-9834-6f3dce28fa4c> | CC-MAIN-2013-20 | http://fatalweb.com/tutorials/12/48/javascript-numbers | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.76974 | 508 | 3.96875 | 4 |
Marion Levine teaches English, Literature and Film Production at Los Angeles Center for Enriched Studies, Los Angeles, CA
Measure for Measure, Act 4 or 5
What's On for Today and Why
Students will choose a character from Measure for Measure and create a "back story" for that character. This will encourage students to read the text closely looking for clues regarding a specific character's history. Students will re-read a portion of the text and then write about what has happened to the character before the play begins. They will then create an artifact, such as a diary or journal entry, written by the charcacter they have selected. This will allow them the opportunity to think like the character and to view the events of the play from a specific point of view.
This lesson will take two 40 minute class periods.
What You Need
Measure for Measure, Folger Edition
What To Do
1. Explain the concept of a "back story" as the important events that occur to a character before the play begins. You may need to prompt students with questions such as:
What was the character like as a child?
In what situation did he/she grow up?
Students will need to show how the script supports their choices.
2. Have the students write a one or two page back story in either the first or third person.
3. Divide students into small groups of 4 or 5 and have them re-read Act 4 or Act 5, combing throught the text for character details.
4. Have students write a letter, diary or journal entry from their selected characters point of view (first person). This artifact should concern one or more characters in the play.
5. For increased authenticity, appropriate for an "Extra-Extended" book, students could write their letter, diary entry using calligraphy, a handwriting font or on a piece of yellowed paper.
6. Allow students time to read their pieces and share their artifacts with the class.
How Did It Go?
Were students able to justify their choices with reference to the text? Did their artifacts accurately portray character traits that can be interpreted from the text? Were students able to convey a sense of the character's perspective through this activity?
This lesson could be applied to any fictional text that the students read in class. Through close reading and attention to a specific character, students are able to identify with, and understand the concerns of a character on a deeper level. Possible choices could include Jay Gatsby, Hester Prynne,and Atticus Finch.
If you used this lesson, we would like to hear how it went and about any adaptations you made to suit the needs of YOUR students. | <urn:uuid:86849ab7-4070-40ee-9f28-f23c0e6d4e97> | CC-MAIN-2013-20 | http://folger.edu/eduLesPlanDtl.cfm?lpid=863 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.948124 | 553 | 4.0625 | 4 |
The basics of heat stress
When the thermometer rises, it can-and often does-create a multitude of problems. Anyone, given the right (or wrong) conditions, can get heat stress. Some are lucky enough to suffer only from heat cramps, while those who are less fortunate may be laid up by heat exhaustion or devastated by heat stroke. As the long, hot days of summer approach, it is helpful to review the effects of warm weather on the human body, the illnesses that may result and what you can do.
How the body stays cool Unknowingly, you constantly engage your body in the life-and-death struggle to disperse the heat it produces. If allowed to accumulate, this heat would quickly increase your body temperature beyond its comfortable 98.6oF. This does not normally happen because your body is able to lose enough heat to maintain a steady temperature. You become aware of this struggle for heat balance during hard labor or exercise in hot environments, when your body produces heat faster than it can lose it. Under certain conditions, your body may build up too much heat, your temperature may rise to life-threatening levels, and you may become delirious or lose consciousness. This is called heat stroke, and it is a serious medical emergency. If you do not rid your body of excess heat fast enough, it cooks the brain and other vital organs. It often is fatal, and those who survive may have permanent damage to their vital organs. Before your temperature reaches heat-stroke levels, however, you may suffer heat exhaustion with its flu-like symptoms, and while treating its symptoms you avoid heat stroke.
How does your body dispose of excess heat? Humans lose heat largely through their skin, similar to how a car loses heat through its radiator. Exercising muscles warms the blood, just as a car's hot engine warms its radiator fluid. Warm blood travels through the skin's dilated blood vessels losing heat by evaporating sweat to the surrounding air, just like a car loses engine heat through its radiator.
When blood delivers heat to the skin, two of the most important ways the body loses heat are radiation and evaporation (vaporization of sweat). When the temperature is 70oF or less, the body releases its heat by radiation. As environmental temperatures approach your body temperature, you lose less heat through radiation. In fact, people working on hot summer days actually gain heat through radiation from the sun. This leaves evaporation as the only way to effectively control body temperature.
Water loss Your body is about half water. You lose about 2 quarts every day (breathing, urinating, bowel movements and sweat). A working adult can produce 2 quarts of sweat per hour for short periods and up to 15 quarts per day. Because the body's water absorption rate of 1.5 quarts per hour is less than the body's 2 quarts per hour sweat rate, dehydration results. This happens because you cannot drink enough water to keep up with your sweat losses.
If you drink only when you are thirsty, you are dehydrated already. Thirst is not a good guide for when to drink water. In fact, in hot and humid conditions, you may be so dehydrated by the time you become thirsty that you will have trouble catching up with your fluid losses. One guideline regarding your water intake is to monitor your urine. You are getting enough water if you produce clear urine at least five times a day. Cloudy or dark urine, or urinating less than five times a day, means you should drink more.
In the Gulf War, American armed forces followed the practice of the Israeli army: drinking a minimum of 1 quart of fluid per hour. This tactic resulted in zero deaths from heat illness. In contrast, during the Six Day War of 1967, more than 20,000 Egyptian soldiers died3/4with no visible wounds3/4most likely from dehydration and heat illness because they were restricted to 3 quarts daily.
While working in hot weather, drink 8 ounces of water every 20 minutes. Generally, 16 ounces is the most a person can comfortably drink at once. You cannot "catch up" by drinking extra water later because only about 1 quart of water per hour can pass out of the stomach. Therefore, if possible, workers should begin drinking water before they start work.
Cool water (50oF) is easier for the stomach to absorb than warm water, and a little flavoring may make the water more tasty. The best fluids are those that leave the stomach fast and contain little sodium and some sugar (less than 8 percent). You should avoid coffee and tea because they contain caffeine, which is a diuretic that increases water loss through urination. Alcoholic beverages also dehydrate by increasing urination. Soda pop contains about 10 percent sugar and, therefore, your body does not absorb it as well as water or commercial sports drinks. The sugar content of fruit juices ranges from 11 to 18 percent and has an even longer absorption time. Commercial sports drinks contain about 5 to 8 percent sugar.
Electrolyte loss Sweat and urine contain potassium and sodium, which are essential electrolytes that control the movement of water in and out of the body's cells. Many everyday foods contain these electrolytes. Bananas and nuts are rich with potassium, and most American diets have up to 10 times as much sodium as the body needs. Getting enough salt is rarely a problem in the typical American diet. In fact, most Americans consume an excessive amount of sodium-averaging 5 to 10 grams of sodium per day-although we probably require only 1 to 3 grams. Therefore, sodium loss is seldom a problem, unless a person is sweating profusely for long periods and drinking large amounts of water.
Commercial sports drinks can be useful if you are participating in vigorous physical activity for longer than 1 hour (some experts say longer than 4 hours). Most of the time, however, people merely require water to remain hydrated. The truth is that excessive sodium can draw water out of the body cells, accentuating the dehydration. In addition, drinking large amounts of water (more than 1 quart an hour) can cause water intoxication, a condition that flushes electrolytes from the body. Frequent urination and behavior changes (irrationality, combativeness, coma, seizures, etc.) are signs of water intoxication.
Effects of humidity Sweat can only cool the body if it evaporates. In dry air, you will not notice sweat evaporating. However, sweat cannot evaporate in high-humidity conditions; it just drips off the skin. At about 70-percent humidity, sweating is ineffective in cooling the body.
Because humidity can significantly reduce evaporative cooling, a highly humid but mildly warm day can be more stressful than a hot, dry one. Therefore, the higher the humidity, the lower the temperature at which heat risk begins, especially those who are generating heat with vigorous work.
Who is at risk? Everyone is susceptible to heat illness if environmental conditions overwhelm the body's temperature-regulating mechanisms. Heat waves can set the stage for a rash of heat-stroke victims. For example, during the 1995 summer heat wave in Chicago, the death toll reached 590.
People who are obese, chronically ill or alcoholics have an increased risk. The elderly are at higher risk because of impaired cardiac output and decreased ability to sweat. Infants and young children also are susceptible to heat stroke, as well.
The fluid loss and dehydration resulting from physical activity puts outdoor laborers at particular risk. Certain medications predispose individuals to heat stroke, such as drugs that alter sweat production (antihistamines, antipsychotics, antidepressants) or interfere with thermoregulation.
Heat illnesses Several disorders exist along the spectrum of heat illnesses. Heat cramps, heat exhaustion and heat stroke are on the more serious side of the scale, whereas heat syncope, heat edema and prickly heat are less serious (see "Heat illnesses," page C 18). Only heat stroke is life-threatening. Untreated heat-stroke victims always die.
* Heat cramps are painful muscular spasms that occur suddenly. They usually involve the muscles in the back of the leg or the abdominal muscles. They tend to occur immediately after exertion and are caused by salt depletion. Victims may be drinking water without adequate salt content. However, some experts disagree because the typical American diet is heavy with salt.
* Heat exhaustion is characterized by heavy perspiration with normal or slightly above-normal body temperatures. A depletion of water or salt3/4or both3/4causes this condition. Some experts believe severe dehydration is a better term because it happens to workers who do not drink enough fluids while working in hot environments. Symptoms include severe thirst, fatigue, headache, nausea, vomiting and diarrhea. The affected person often mistakenly believes he or she has the flu. Uncontrolled heat exhaustion can evolve into heat stroke.
* Heat stroke is classified in two ways: classic and exertional. Classic heat stroke, also known as the "slow cooker," may take days to develop. This condition is prevalent during summer heat waves and typically affects poor, elderly, chronically ill, alcoholic or obese persons. Because the elderly often have medical problems, heat stroke exacerbates the problem, and more than 50 percent of elderly heat-stroke victims die3/4even with medical care. Death results from a combination of a hot environment and dehydration. Exertional heat stroke also is more common in the summer. You see it frequently in athletes, laborers and military personnel who sweat profusely. Known as the "fast cooker," this condition affects healthy, active individuals who strenuously work or play in a warm environment. Exertional heat-stroke victims usually are sweating when stricken, while the classic victims are not sweating. Its rapid onset does not allow enough time for severe dehydration to occur.
Because uncontrolled heat exhaustion can evolve into heat stroke, you should know how to tell the difference between them. If the victim feels extremely hot when touched, suspect heat stroke. Another mark of heat stroke is that the victim's mental status (behavior) changes drastically3/4ranging from being slightly confused and disoriented to falling into a coma. In between these conditions, victims usually become irrational, agitated or even aggressive and may have seizures. In severe cases, the victim can go into a coma in less than 1 hour. The longer a coma lasts, the lower the chance for survival, so rescuers must be quick.
A third way of distinguishing heat stroke from heat exhaustion is by rectal temperature. Obviously, this is not very practical because conscious heat-stroke victims may not cooperate. Taking a rectal temperature can be embarrassing to both victim and rescuer. Moreover, rectal thermometers are seldom available, and the whole procedure of finding the appropriate thermometer and then using it wastes time and distracts from important emergency care. In most cases, an ambulance arrives within 10 to 20 minutes.
* Heat syncope, in which a person becomes dizzy or faints after exposure to high temperatures, is a self-limiting condition. Victims should lie down in a cool place when it occurs. Victims who are not nauseated can drink water.
* Heat edema, which is also a self-limiting condition, causes ankles and feet to swell from heat exposure. It is more common in women unacclimated to a hot climate. It is related to salt and water retention and tends to disappear after acclimation. Wearing support stockings and elevating the legs often helps reduce swelling.
* Prickly heat, also known as a heat rash, is an itchy rash that develops on skin that is wet from sweating. Dry and cool the skin.
Cooling methods Sometimes the only way to stop possible damage is to cool the victim as quickly as possible. However, it is important to pay attention to both the cooling methods and cautions.
* Ice baths cool a victim quickly but require a great deal of ice3/4at least 80 pounds3/4to be effective. Needing a big enough tub also limits this method. Cool-water baths3/4(less than 60oF)3/4can be successful if you stir the water to prevent a warm layer from forming around the body. This is the most effective method in highly humid conditions (greater than 75-percent humidity).
* Spraying the victim with water combined with fanning is another method for cooling the body. The water droplets act as artificial sweat and cool the body through evaporation. However, this method is not effective in high humidity3/4greater than 75 percent.
* Ice bags wrapped in wet towels and placed against the large veins in the groin, armpits and sides of the neck also cool the body, though not nearly as quickly as immersion.
Cautions to remember when employing any cooling method include: * Do not delay the onset of cooling while waiting for an ambulance. Doing so increases the risk of tissue damage and prolonged hospitalization. * Stop cooling when the victim's mental status improves to avoid hypothermia. * Do not use rubbing alcohol to cool the skin. It can be absorbed into the blood, causing alcohol poisoning. Its vapors are a potential fire hazard. * Do not use aspirin or acetaminophen. They are not effective because the brain's control-center temperature is not elevated as it is with fever caused by diseases.
Adjusting to heat Most heat illness occur during the first days of working in the heat. Therefore, acclimation (adjusting to the heat) is the main preventive measure. To better handle the heat, the body adjusts by decreasing the salt content in sweat and increases the sweating rate. Year-round exercise can help workers prepare for hot weather. Such activity raises the body's core temperature so it becomes accustomed to heat. Full acclimation, however, requires exercise in hot weather. You can do this by exercising a minimum of 60 to 90 minutes in the heat each day for 1 to 2 weeks.
The acclimated heart pumps more blood with each stroke than a heart unused to working in the heat. Sweating earlier and doubles the amount of sweat per hour from 1.5 quarts to 3 quarts or more.
When new workers are exposed to hot weather, team them with veterans of the heat who know how much water to drink. Heat illnesses are avoidable. With knowledge, preparation, fluid replacement and prompt emergency care, heat casualties need not be a factor for those working in warm weather.
Dr. Alton Thygerson is a professor of health science at Brigham Young University, Provo, Utah. He also serves as the technical consultant for the National Safety Council's First Aid Institute.
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Chinese researchers have turned to the light absorbing properties of butterfly wings to significantly increase the efficiency of solar hydrogen cells, using biomimetics to copy the nanostructure that allows for incredible light and heat absorption.
Butterflies are known to use heat from the sun to warm themselves beyond what their bodies can provide, and this new research takes a page from their evolution to improve hydrogen fuel generation. Analyzing the wings of Papilio helenus, the researchers found scales that are described as having:
[...] Ridges running the length of the scale with very small holes on either side that opened up onto an underlying layer. The steep walls of the ridges help funnel light into the holes. The walls absorb longer wavelengths of light while allowing shorter wavelengths to reach a membrane below the scales. Using the images of the scales, the researchers created computer models to confirm this filtering effect. The nano-hole arrays change from wave guides for short wavelengths to barriers and absorbers for longer wavelengths, which act just like a high-pass filtering layer.
So, what does this have to do with fuel cells? Splitting water into hydrogen and oxygen takes energy, and is a drain on the amount you can get out of a cell. To split the water, the process uses a catalyst, and certain catalysts — say, titanium dioxide — function by exposure to light. The researchers synthesized a titanium dioxide catalyst using the pattern from the butterfly's wings, and paired it with platinum nanoparticles to make it more efficient at splitting water. The result? A 230% uptick in the amount of hydrogen produced. The structure of the butterfly's wing means that it's better at absorbing light — so who knows, you might also see the same technique on solar panels, too. | <urn:uuid:9a374252-df3c-4004-8693-6678182914d9> | CC-MAIN-2013-20 | http://io9.com/5897144/mimicking-butterfly-wings-could-boost-hydrogen-fuel-production | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.92605 | 355 | 3.765625 | 4 |
You may associate pneumonia with the melodrama of a soap opera: prolonged hospital stays, oxygen tents, and family members whispering in bedside huddles. It's true that pneumonia can be serious. But more often pneumonia is an infection that can be easily treated at home without a hospital stay.
What Is Pneumonia?
Pneumonia (pronounced: noo-mow-nyuh) is an infection of the lungs. When someone has pneumonia, lung tissue can fill with pus and other fluid, which makes it difficult for oxygen in the lung's air sacs to reach the bloodstream. With pneumonia, a person may have difficulty breathing and have a cough and fever; occasionally, chest or abdominal pain and vomiting are symptoms, too.
Pneumonia is commonly caused by viruses, such as the influenza virus(flu) and adenovirus. Other viruses, such as respiratory syncytial virus(RSV), are common causes of pneumonia in young children and infants.
Bacteria such as Streptococcus pneumoniae can cause pneumonia, too. People with bacterial pneumonia are usually sicker than those with viral pneumonia, but can be effectively treated with antibiotic medications.
You might have heard the terms "double pneumonia" or "walking pneumonia." Double pneumonia simply means that the infection is in both lungs. It's common for pneumonia to affect both lungs, so don't worry if your doctor says this is what you have — it doesn't mean you're twice as sick.
Walking pneumonia refers to pneumonia that is mild enough that you may not even know you have it. Walking pneumonia (also called atypical pneumonia because it's different from the typical bacterial pneumonia) is common in teens and is often caused by a tiny microorganism, Mycoplasma pneumoniae. Like the typical bacterial pneumonia, walking pneumonia also can be treated with antibiotics.
What Are the Signs and Symptoms?
Many symptoms are associated with pneumonia; some of them, like a cough or a sore throat, are also common with other common infections. Often, people get pneumonia after they've had an upper respiratory tract infection like a cold.
Symptoms of pneumonia can include:
unusually rapid breathing
chest or abdominal pain
loss of appetite
vomiting and dehydration
Symptoms vary from person to person, and few people get all of them.
When pneumonia is caused by bacteria, a person tends to become sick quickly and develops a high fever and has difficulty breathing. When it's caused by a virus, symptoms generally appear more gradually and might be less severe.
Someone's symptoms can help the doctor identify the type of pneumonia. Mycoplasma pneumoniae, for example, often causes headaches, sore throats, and rash in addition to the symptoms listed above.
The routine vaccinations that most people receive as kids help prevent certain types of pneumonia and other infections. If you have a chronic illness, such as sickle cell disease, you may have received additional vaccinations and disease-preventing antibiotics to help prevent pneumonia and other infections caused by bacteria.
People with diseases that affect their immune system (like diabetes, HIV infection, or cancer), are 65 or older, or are in other high-risk groups should receive a pneumococcal vaccination. They also may receive antibiotics to prevent pneumonia that can be caused by organisms they're especially susceptible to. In some cases, antiviral medication might be used to prevent viral pneumonia or to lessen its effects.
Doctors recommend that everyone 6 months and older gets a flu vaccine. That's because pneumonia often happens as a complication of the flu. Call your doctor's office to see when these vaccines are available.
Because pneumonia is often caused by germs, a good way to prevent it is to keep your distance from anyone you know who has pneumonia or other respiratory infections. Use separate drinking glasses and eating utensils; wash your hands frequently with warm, soapy water; and avoid touching used tissues and paper towels.
You also can stay strong and help avoid some of the illnesses that might lead to pneumonia by eating as healthily as possible, getting a minimum of 8 to 10 hours of sleep a night, and not smoking.
How Long Does It Last?
The length of time between exposure and feeling sick (called the incubation period) depends on many factors, particularly the type of pneumonia involved.
With influenza pneumonia, for example, someone may become sick as soon as 12 hours or as long as 3 days after exposure to the flu virus. But with walking pneumonia, a person may not have symptoms until 2 to 3 weeks after becoming infected.
Most types of pneumonia resolve within a week or two, although a cough can linger for several weeks more. In severe cases, it may take longer to completely recover.
If you think you may have pneumonia, tell a parent or other adult and be sure you see a doctor. Be especially aware of your breathing; if you have chest pain or trouble breathing or if your lips or fingers look blue, you should go to a doctor's office or to a hospital emergency department right away.
How Is Pneumonia Treated?
If pneumonia is suspected, the doctor will perform a physical exam and might order a chest X-ray and blood tests. People with bacterial or atypical pneumonia will probably be given antibiotics to take at home. The doctor also will recommend getting lots of rest and drinking plenty of fluids.
Some people with pneumonia need to be hospitalized to get better — usually babies, young kids, and people older than 65. However, hospital care may be needed for a teen who:
already has immune system problems
has cystic fibrosis
is dangerously dehydrated or is vomiting a lot and can't keep fluids and medicine down
has had pneumonia frequently
has skin that's blue or pale in color, which reflects a lack of oxygen
When pneumonia patients are hospitalized, treatment might include intravenous (IV) antibiotics (delivered through a needle inserted into a vein) and respiratory therapy (breathing treatments).
Antiviral medications approved for adults and teens can reduce the severity of flu infections if taken in the first 1 to 2 days after symptoms begin. They're usually prescribed for teens who have certain underlying illnesses such as asthma or who have pneumonia or breathing difficulty.
If you have been exposed to influenza and you begin to develop symptoms of pneumonia, call a doctor.
If your doctor has prescribed medicine, be sure to follow the directions carefully.
You may feel better in a room with a humidifier, which increases the moisture in the air and soothes irritated lungs. Make sure you drink plenty of fluids, especially if you have a fever. If you have a fever and feel uncomfortable, ask the doctor whether you can take over-the-counter medicine such as acetaminophen or ibuprofen to bring it down. But don't take any medicine without checking first with your doctor — a cough suppressant, for example, may not allow your lungs to clear themselves of mucus.
And finally, be sure to rest. This is a good time to sleep, watch TV, read, and lay low. If you treat your body right, it will repair itself and you'll be back to normal in no time. | <urn:uuid:d7bdcf2d-ea1c-4316-a4f7-13bbedd58cdc> | CC-MAIN-2013-20 | http://kidshealth.org/PageManager.jsp?dn=K_HovnanianChildrens_Hospital&lic=184&cat_id=20174&article_set=22204&tracking=T_RelatedArticle | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.958104 | 1,475 | 3.75 | 4 |
See also the
Dr. Math FAQ:
order of operations
Browse High School Basic Algebra
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Solving simple linear equations.
Positive/negative integer rules.
Completing the square.
Direct and indirect variation.
Inequalities and negative numbers.
- Normalization [08/01/2001]
How do I figure out: 90 + 70 + 88 + 94 + x / 5 = 85 ?
- The Nth Root of N [11/28/2000]
Is the nth root of n (a whole number other than 1) ever a rational
- Number of Equations Needed in a Simultaneous Linear System [10/29/2003]
Could you tell me why we need the same number of equations as
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- Number * Sum of Remaining Four Numbers [04/03/2003]
Find 5 numbers such that when each number is multiplied by the sum of
the remaining 4 numbers, the following values will result: 152, 245,
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- Objects in a Pyramid [7/8/1996]
Objects are stacked in a triangular pyramid... how many objects are in
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- Old Test Questions Answered [1/23/1995]
I am studying for my midterm, and I've come across two questions that I
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- One Variable Equations with Decimals [02/11/1997]
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- Open Sentence, Statement [09/18/2001]
What is an open sentence?
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Since the following statement is true: (1+1)**(5-2) is 8, why is the
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- Ordering Exponents and Variables [04/08/2000]
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have the same exponent? What about negative exponents and descending
- Ordering Products, Powers, and Parameters of Trigonometric Functions [10/31/2010]
A student wants to know how to unambiguously interpret strings of trigonometric
functions, multiplication, and exponentiation. Doctor Peterson digs into a history book
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- Order in Linear Expressions [11/20/2001]
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y=13-7x, where y is a function of x, it should be written as y=-7x+13?
- Order of Operations [05/19/1999]
Given a, b, x, and y, find ax/by.
- Order of Operations with Percentages [04/05/2001]
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- Other Ways to Get the Quadratic Formula [02/19/2010]
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128b = 3ab.
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My teacher gave us ten questions to answer and I could do all except two:
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- Polynomial Brain-Twisters [12/4/1995]
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- Polynomial Degrees and Definition of a Field [03/02/1998]
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- Polynomial Problem [3/11/1995]
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remainder of -3 when p(x) is divided by x+2, and a remainder of 3 when
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- Population and Percentage [03/07/1999]
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Find five different positive unit fractions whose sum is 1. (A unit
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between 0 and 5? ...when p and q are greater than 0? | <urn:uuid:7308a886-f8d1-4f71-a8ac-74e6e4712804> | CC-MAIN-2013-20 | http://mathforum.org/library/drmath/sets/high_algebra.html?start_at=441&num_to_see=40&s_keyid=38309224&f_keyid=38309225 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.813244 | 1,828 | 3.609375 | 4 |
Jim Lake and Maria Rivera, at the University of California-Los Angeles (UCLA), report their finding in the Sept. 9 issue of the journal Nature.
Scientists refer to both bacteria and Archaea as "prokaryotes"--a cell type that has no distinct nucleus to contain the genetic material, DNA, and few other specialized components. More-complex cells, known as "eukaryotes," contain a well-defined nucleus as well as compartmentalized "organelles" that carry out metabolism and transport molecules throughout the cell. Yeast cells are some of the most-primitive eukaryotes, whereas the highly specialized cells of human beings and other mammals are among the most complex.
"A major unsolved question in biology has been where eukaryotes came from, where we came from," Lake said. "The answer is that we have two parents, and we now know who those parents were."
Further, he added, the results provide a new picture of evolutionary pathways. "At least 2 billion years ago, ancestors of these two diverse prokaryotic groups fused their genomes to form the first eukaryote, and in the processes two different branches of the tree of life were fused to form the ring of life," Lake said.
The work is part of an effort supported by the National Science Foundation--the federal agency that supports research and education across all disciplines of science and engineering--to re-examine historical schemes for classifying Earth's living creatures, a process that was once based on easily observable traits. Microbes, plants or animals wer
Contact: Leslie Fink
National Science Foundation | <urn:uuid:baf824b2-7e06-471a-8510-efd5abab1567> | CC-MAIN-2013-20 | http://news.bio-medicine.org/biology-news-2/Complex-cells-likely-arose-from-combination-of-bacterial-and-extreme-microbe-genomes-284-1/ | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.954951 | 335 | 3.796875 | 4 |
The test team views the use of a pulley as an intermediate step only, and has planned to shift to a reliance on windlasses like those that apparently were used to hoist sails on Egyptian ships.
"The whole approach has been to downgrade the technology," Gharib said. "We first wanted to show that a kite could raise a huge weight at all. Now that we're raising larger and larger stones, we're also preparing to replace the steel scaffolding with wooden poles and the steel pulleys with wooden pulleys like the ones they may have used on Egyptian ships."
For Gharib, the idea of accomplishing heavy tasks with limited manpower is appealing from an engineer's standpoint because it makes more logistical sense.
"You can imagine how hard it is to coordinate the activities of hundreds if not thousands of laborers to accomplish an intricate task," said Gharib. "It's one thing to send thousands of soldiers to attack another army on a battlefield. But an engineering project requires everything to be put precisely into place.
"I prefer to think of the technology as simple, with relatively few people involved," he explained.
Gharib and Graff came up with a way of building a simple structure around the obelisk, with a pulley system mounted in front of the stone. That way, the base of the obelisk would drag on the ground for a few feet as the kite lifted the stone, and the stone would be quite stable once it was pulled upright into a vertical position. If the obelisk were raised with the base as a pivot, the stone would tend to swing past the vertical position and fall the other way.
The top of the obelisk is tied with ropes threaded through the pulleys and attached to the kite. The operation is guided by a couple of workers using ropes attached to the pulleys.
No one has found any evidence that the ancient Egyptians moved stones or any other objects with kites and pulleys. But Clemmons has found some tantalizing hints that the project is on the right track. On a building frieze in a Cairo museum, there is a wing pattern in bas-relief that does not resemble any living bird. Directly below are several men standing near vertical objects that could be ropes.
Gharib's interest in the project is mainly to demonstrate that the technique may be viable.
"We're not Egyptologists," he said. "We're mainly interested in determining whether there is a possibility that the Egyptians were aware of wind power, and whether they used it to make their lives better."
Now that Gharib and his team have successfully raised the four-ton concrete obelisk, they plan to further test the approach using a ten-ton stone, and perhaps an even heavier one after that. Eventually they hope to obtain permission to try using their technique to raise one of the obelisks that still lie in an Egyptian quarry.
"In fact, we may not even need a kite. It could be we can get along with just a drag chute," Gharib said.
An important question is: Was there enough wind in Egypt for a kite or a drag chute to fly? Probably so, as steady winds of up to 30 miles per hour are not unusual in the areas where pyramids and obelisks were found.
(c) 2001 Caltech
SOURCES AND RELATED WEB SITES | <urn:uuid:7989d2d3-3e6d-4a4d-ad8e-e7b19882a89a> | CC-MAIN-2013-20 | http://news.nationalgeographic.com/news/2001/06/0628_caltechobelisk_2.html | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.974171 | 709 | 3.578125 | 4 |
Topics covered: Ideal solutions
Instructor/speaker: Moungi Bawendi, Keith Nelson
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PROFESSOR: So. In the meantime, you've started looking at two phase equilibrium. So now we're starting to look at mixtures. And so now we have more than one constituent. And we have more than one phase present. Right? So you've started to look at things that look like this, where you've got, let's say, two components. Both in the gas phase. And now to try to figure out what the phase equilibria look like. Of course it's now a little bit more complicated than what you went through before, where you can get pressure temperature phase diagrams with just a single component. Now we want to worry about what's the composition. Of each of the components. In each of the phases. And what's the temperature and the pressure. Total and partial pressures and all of that. So you can really figure out everything about both phases. And there are all sorts of important reasons to do that, obviously lots of chemistry happens in liquid mixtures. Some in gas mixtures. Some where they're in equilibrium. All sorts of chemical processes. Distillation, for example, takes advantage of the properties of liquid and gas mixtures. Where one of them might be richer, will be richer, and the more volatile of the components. That can be used as a basis for purification. You mix ethanol and water together so you've got a liquid with a certain composition of each. The gas is going to be richer and the more volatile of the two, the ethanol. So in a distillation, where you put things up in the gas, more of the ethanol comes up. You could then collect that gas, right? And re-condense it, and make a new liquid. Which is much richer in ethanol than the original liquid was. Then you could make, then you could put some of them up into the gas phase. Where it will be still richer in ethanol. And then you could collect that and repeat the process. So the point is that properties of liquid gas, two-component or multi-component mixtures like this can be exploited. Basically, the different volatilities of the different components can be exploited for things like purification.
Also if you want to calculate chemical equilibria in the liquid and gas phase, of course, now you've seen chemical equilibrium, so the amount of reaction depends on the composition. So of course if you want reactions to go, then this also can be exploited by looking at which phase might be richer in one reactant or another. And thereby pushing the equilibrium toward one direction or the other. OK. So. we've got some total temperature and pressure. And we have compositions. So in the gas phase, we've got mole fractions yA and yB. In the liquid phase we've got mole fractions xA and xB. So that's our system. One of the things that you established last time is that, so there are the total number of variables including the temperature and the pressure. And let's say the mole fraction of A in each of the liquid and gas phases, right? But then there are constraints. Because the chemical potentials have to be equal, right? Chemical potential of A has to be equal in the liquid and gas. Same with B. Those two constraints reduce the number of independent variables. So there'll be two in this case rather than four independent variables. If you control those, then everything else will follow. What that means is if you've got a, if you control, if you fix the temperature and the total pressure, everything else should be determinable. No more free variables.
And then, what you saw is that in simple or ideal liquid mixtures, a result called Raoult's law would hold. Which just says that the partial pressure of A is equal to the mole fraction of A in the liquid times the pressure of pure A over the liquid. And so what this gives you is a diagram that looks like this. If we plot this versus xB, this is mole fraction of B in the liquid going from zero to one. Then we could construct a diagram of this sort. So this is the total pressure of A and B. The partial pressures are given by these lines. So this is our pA star and pB star. The pressures over the pure liquid A and B at the limits of mole fraction of B being zero and one. So in this situation, for example, A is the more volatile of the components. So it's partial pressure over its pure liquid. At this temperature. Is higher than the partial pressure of B over its pure liquid. A would be the ethanol, for example and B the water in that mixture. OK. Then you started looking at both the gas and the liquid phase in the same diagram. So this is the mole fraction of the liquid. If you look and see, well, OK now we should be able to determine the mole fraction in the gas as well. Again, if we note total temperature and pressure, everything else must follow.
And so, you saw this worked out. Relation between p and yA, for example. The result was p is pA star times pB star over pA star plus pB star minus pA star times yA. And the point here is that unlike this case, where you have a linear relationship, the relationship between the pressure and the liquid mole fraction isn't linear. We can still plot it, of course. So if we do that, then we end up with a diagram that looks like the following. Now I'm going to keep both mole fractions, xB and yB, I've got some total pressure. I still have my linear relationship. And then I have a non-linear relationship between the pressure and the mole fraction in the gas phase. So let's just fill this in. Here is pA star still. Here's pB star. Of course, at the limits they're still, both mole fractions they're zero and one.
OK. I believe this is this is where you ended up at the end of the last lecture. But it's probably not so clear exactly how you read something like this. And use it. It's extremely useful. You just have to kind of learn how to follow what happens in a diagram like this. And that's what I want to spend some of today doing. Is just, walking through what's happening physically, with a container with a mixture of the two. And how does that correspond to what gets read off the diagram under different conditions. So. Let's just start somewhere on a phase diagram like this.
Let's start up here at some point one, so we're in the pure - well, not pure, you're in the all liquid phase. It's still a mixture. It's not a pure substance. pA star, pB star. There's the gas phase. So, if we start at one, and now there's some total pressure. And now we're going to reduce it. What happens? We start with a pure - with an all-liquid mixture. No gas. And now we're going to bring down the pressure. Allowing some of the liquid to go up into the gas phase. So, we can do that. And once we reach point two, then we find a coexistence curve. Now the liquid and gas are going to coexist. So this is the liquid phase. And that means that this must be xB. And it's xB at one, but it's also xB at two, and I want to emphasize that. So let's put our pressure for two. And if we go over here, this is telling us about the mole fraction in the gas phase. That's what these curves are, remember. So this is the one that's showing us the mole fraction in the liquid phase. This nonlinear one in the gas phase. So that means just reading off it, this is xB, that's the liquid mole fraction. Here's yB. The gas mole fraction. They're not the same, right, because of course the components have different volatility. A's more volatile.
So that means that the mole fraction of B in the liquid phase is higher than the mole fraction of B in the gas phase. Because A is the more volatile component. So more, relatively more, of A, the mole fraction of A is going to be higher up in the gas phase. Which means the mole fraction of B is lower in the gas phase. So, yB less than xB if A is more volatile. OK, so now what's happening physically? Well, we started at a point where we only had the liquid present. So at our initial pressure, we just have all liquid. There's some xB at one. That's all there is, there isn't any gas yet. Now, what happened here? Well, now we lowered the pressure. So you could imagine, well, we made the box bigger. Now, if the liquid was under pressure, being squeezed by the box, right then you could make the box a little bit bigger. And there's still no gas. That's moving down like this. But then you get to a point where there's just barely any pressure on top of the liquid. And then you keep expanding the box. Now some gas is going to form.
So now we're going to go to our case two. We've got a bigger box. And now, right around where this was, this is going to be liquid. And there's gas up here. So up here is yB at pressure two. Here's xB at pressure two. Liquid and gas. So that's where we are at point two here.
Now, what happens if we keep going? Let's lower the pressure some more. Well, we can lower it and do this. But really if we want to see what's happening in each of the phases, we have to stay on the coexistence curves. Those are what tell us what the pressures are. What the partial pressure are going to be in each of the phases. In each of the two, in the liquid and the gas phases. So let's say we lower the pressure a little more. What's going to happen is, then we'll end up somewhere over here. In the liquid, and that'll correspond to something over here in the gas. So here's three.
So now we're going to have, that's going to be xB at pressure three. And over here is going to be yB at pressure three. And all we've done, of course, is we've just expanded this further. So now we've got a still taller box. And the liquid is going to be a little lower because some of it has evaporated, formed the gas phase. So here's xB at three. Here's yB at three, here's our gas phase. Now we could decrease even further. And this is the sort of thing that you maybe can't do in real life. But I can do on a blackboard. I'm going to give myself more room on this curve, to finish this illustration. There. Beautiful. So now we can lower a little bit further, and what I want to illustrate is, if we keep going down, eventually we get to a pressure where now if we look over in the gas phase, we're at the same pressure, mole fraction that we had originally in the liquid phase. So let's make four even lower pressure. What does that mean? What it means is, we're running out of liquid. So what's supposed to happen is A is the more volatile component. So as we start opening up some room for gas to form, you get more of A in the gas phase. But of course, and the liquid is richer in B. But of course, eventually you run out of liquid. You make the box pretty big, and you run out, or you have the very last drop of liquid. So what's the mole fraction of B in the gas phase? It has to be the same as what it started in in the liquid phase. Because after all the total number of moles of A and B hasn't changed any. So if you take them all from the liquid and put them all up into the gas phase, it must be the same. So yB of four. Once you just have the last drop. So then yB of four is basically equal to xB of one. Because everything's now up in the gas phase. So in principle, there's still a tiny, tiny bit of xB at pressure four.
Well, we could keep lowering the pressure. We could make the box a little bigger. Then the very last of the liquid is going to be gone. And what'll happen then is, we're all here. There's no more liquid. We're not going down on the coexistence curve any more. We don't have a liquid gas coexistence any more. We just have a gas phase. Of course, we can continue to lower the pressure. And then what we're doing is just going down here. So there's five. And five is the same as this only bigger. And so forth.
OK, any questions about how this works? It's really important to just gain facility in reading these things and seeing, OK, what is it that this is telling you. And you can see it's not complicated to do it, but it takes a little bit of practice. OK.
Now, of course, we could do exactly the same thing starting from the gas phase. And raising the pressure. And although you may anticipate that it's kind of pedantic, I really do want to illustrate something by it. So let me just imagine that we're going to do that. Let's start all in the gas phase. Up here's the liquid. pA star, pB star. And now let's start somewhere here. So we're down somewhere in the gas phase with some composition. So it's the same story, except now we're starting here. It's all gas. And we're going to start squeezing. We're increasing the pressure. And eventually here's one, will reach two, so of course here's our yB. We started with all gas, no liquid. So this is yB of one. It's the same as yB of two, I'm just raising the pressure enough to just reach the coexistence curve. And of course, out here tells us xB of two, right? So what is it saying? We've squeezed and started to form some liquid. And the liquid is richer in component B. Maybe it's ethanol water again. And we squeeze, and now we've got more water in the liquid phase than in the gas phase. Because water's the less volatile component. It's what's going to condense first.
So the liquid is rich in the less volatile of the components. Now, obviously, we can continue in doing exactly the reverse of what I showed you. But all I want to really illustrate is, this is a strategy for purification of the less volatile component. Once you've done this, well now you've got some liquid. Now you could collect that liquid in a separate vessel.
So let's collect the liquid mixture with xB of two. So it's got some mole fraction of B. So we've purified that. But now we're going to start, we've got pure liquid. Now let's make the vessel big. So it all goes into the gas phase. Then lower p. All gas. So we start with yB of three, which equals xB of two. In other words, it's the same mole fraction. So let's reconstruct that. So here's p of two. And now we're going to go to some new pressure. And the point is, now we're going to start, since the mole fraction in the gas phase that we're starting from is the same number as this was. So it's around here somewhere. That's yB of three equals xB of two. And we're down here. In other words, all we've done is make the container big enough so the pressure's low and it's all in the gas phase. That's all we have, is the gas. But the composition is whatever the composition is that we extracted here from the liquid. So this xB, which is the liquid mole fraction, is now yB, the gas mole fraction. Of course, the pressure is different. Lower than it was before.
Great. Now let's increase. So here's three. And now let's increase the pressure to four. And of course what happens, now we've got coexistence. So here's liquid. Here's gas. So, now we're over here again. There's xB at pressure four. Pure still in component B. We can repeat the same procedure. Collect it. All liquid, put it in a new vessel. Expand it, lower the pressure, all goes back into the gas phase. Do it all again. And the point is, what you're doing is walking along here. Here to here. Then you start down here, and go from here to here. From here to here. And you can purify. Now, of course, the optimal procedure, you have to think a little bit. Because if you really do precisely what I said, you're going to have a mighty little bit of material each time you do that. So yes it'll be the little bit you've gotten at the end is going to be really pure, but there's not a whole lot of it. Because, remember, what we said is let's raise the pressure until we just start being on the coexistence curve. So we've still got mostly gas. Little bit of liquid. Now, I could raise the pressure a bit higher. So that in the interest of having more of the liquid, when I do that, though, the liquid that I have at this higher pressure won't be as enriched as it was down here. Now, I could still do this procedure. I could just do more of them. So it takes a little bit of judiciousness to figure out how to optimize that. In the end, though, you can continue to walk your way down through these coexistence curves and purify repeatedly the component B, the less volatile of them, and end up with some amount of it. And there'll be some balance between the amount that you feel like you need to end up with and how pure you need it to be. Any questions about how this works?
So purification of less volatile components. Now, how much of each of these quantities in each of these phases? So, pertinent to this discussion, of course we need to know that. If you want to try to optimize a procedure like that, of course it's going to be crucial to be able to understand and calculate for any pressure that you decide to raise to, just how many moles do you have in each of the phases? So at the end of the day, you can figure out, OK, now when I reach a certain degree of purification, here's how much of the stuff I end up with. Well, that turns out to be reasonably straightforward to do. And so what I'll go through is a simple mathematical derivation. And it turns out that it allows you to just read right off the diagram how much of each material you're going to end up with.
So, here's what happens. This is something called the lever rule. How much of each component is there in each phase? So let's consider a case like this. Let me draw yet once again, just to get the numbering consistent. With how we'll treat this. So we're going to start here. And I want to draw it right in the middle, so I've got plenty of room. And we're going to go up to some pressure. And somewhere out there, now I can go to my coexistence curves. Liquid. And gas. And I can read off my values. So this is the liquid xB. So I'm going to go up to some point two, here's xB of two. Here's yB of two. Great. Now let's get these written in.
So let's just define terms a little bit. nA, nB. Or just our total number of moles. ng and n liquid, of course, total number of moles. In the gas and liquid phases. So let's just do the calculation for each of these two cases. We'll start with one. That's the easier case. Because then we have only the gas. So at one, all gas. It says pure gas in the notes, but of course that isn't the pure gas. It's the mixture of the two components. So. How many moles of A? Well it's the mole fraction of A in the gas. Times the total number of moles in the gas. Let me put one in here. Just to be clear. And since we have all gas, the number of moles in the gas is just the total number of moles. So this is just yA at one times n total. Let's just write that in. And of course n total is equal to nA plus nB.
So now let's look at condition two. Now we have to look a little more carefully. Because we have a liquid gas mixture. So nA is equal to yA at pressure two. Times the number of moles of gas at pressure two. Plus xA, at pressure two, times the number of moles of liquid at pressure two.
Now, of course, these things have to be equal. The total number of moles of A didn't change, right? So those are equal. Then yA of two times ng of two. Plus xA of two times n liquid of two, that's equal to yA of one times n total. Which is of course equal to yA of one times n gas at two plus n liquid at two. I suppose I could be, add that equality. Of course, it's an obvious one. But let me do it anyway. The total number of moles is equal to nA plus nB. But it's also equal to n liquid plus n gas. And that's all I'm taking advantage of here.
And now I'm just going to rearrange the terms. So I'm going to write yA at one minus yA at two, times ng at two, is equal to, and I'm going to take the other terms, the xA term. xA of two minus yA of one times n liquid at two. So I've just rearranged the terms. And I've done that because now, I think I omitted something here. yA of one times ng. No, I forgot a bracket, is what I did. yA of one there. And I did this because now I want to do is look at the ratio of liquid to gas at pressure two. So, ratio of I'll put it gas to liquid, that's ng of two over n liquid at two. And that's just equal to xA of two minus yA at one minus yA at one minus yA at two.
So what does it mean? It's the ratio of these lever arms. That's what it's telling me. I can look, so I raise the pressure up to two. And so here's xB at two, here's yB at two. And I'm here somewhere. And this little amount and this little amount, that's that difference. And it's just telling me that ratio of those arms is the ratio of the total number of moles of gas to liquid. And that's great. Because now when I go back to the problem that we were just looking at, where I say, well I'm going to purify the less volatile component by raising the pressure until I'm at coexistence starting in the gas phase. Raise the pressure, I've got some liquid. But I also want some finite amount of liquid. But I don't want to just, when I get the very, very first drop of liquid now collected, of course it's enriched in the less volatile component. But there may be a minuscule amount, right? So I'll raise the pressure a bit more. I'll go up in pressure. And now, of course, when I do that the amount of enrichment of the liquid isn't as big as it was if I just raised it up enough to barely have any liquid. Then I'd be out here. But I've got more material in the liquid phase to collect. And that's what this allows me to calculate. Is how much do I get in the end. So it's very handy. You can also see, if I go all the way to the limit where the mole fraction in the liquid at the end is equal to what it was in the gas when I started, what that says is that there's no more gas left any more. In other words, these two things are equal. If I go all the way to the point where I've got all the, this is the amount I started with, in the pure gas phase, now I keep raising it all the way. Until I've got the same mole fraction in the liquid. Of course, we know what that really means. That means that I've gone all the way from pure gas to pure liquid. And the mole fraction in that case has to be the same. And what this is just telling us mathematically is, when that happens this is zero. That means I don't have any gas left. Yeah.
PROFESSOR: No. Because, so it's the mole fraction in the gas phase. But you've started with some amount that it's only going to go down from there.
PROFESSOR: Yeah. Yeah. Any other questions? OK.
Well, now what I want to do is just put up a slightly different kind of diagram, but different in an important way. Namely, instead of showing the mole fractions as a function of the pressure. And I haven't written it in, but all of these are at constant temperature, right? I've assumed the temperature is constant in all these things. Now let's consider the other possibility, the other simple possibility, which is, let's hold the pressure constant and vary the temperature. Of course, you know in the lab, that's usually what's easiest to do. Now, unfortunately, the arithmetic gets more complicated. It's not monumentally complicated, but here in this case, where you have one linear relationship, which is very convenient. From Raoult's law. And then you have one non-linear relationship there for the mole fraction of the gas. In the case of temperature, they're both, neither one is linear. Nevertheless, we can just sketch what the diagram looks like. And of course it's very useful to do that, and see how to read off it. And I should say the derivation of the curves isn't particularly complicated. It's not particularly more complicated than what I think you saw last time to derive this. There's no complicated math involved. But the point is, the derivation doesn't yield a linear relationship for either the gas or the liquid part of the coexistence curve.
OK, so we're going to look at temperature and mole fraction phase diagrams. Again, a little more complicated mathematically but more practical in real use. And this is T. And here is the, sort of, form that these things take. So again, neither one is linear. Up here, now, of course if you raise the temperatures, that's where you end up with gas. If you lower the temperature, you condense and get the liquid. So, this is TA star. TB star. So now I want to stick with A as the more volatile component. At constant temperature, that meant that pA star is bigger than pB star. In other words, the vapor pressure over pure liquid A is higher than the vapor pressure over pure liquid B. Similarly, now I've got constant pressure and really what I'm looking at, let's say I'm at the limit where I've got the pure liquid. Or the pure A. And now I'm going to, let's say, raise the temperature until I'm at the liquid-gas equilibrium. That's just the boiling point. So if A is the more volatile component, it has the lower boiling point. And that's what this reflects. So higher pB star A corresponds to lower TA star A. Which is just the boiling point of pure A.
So, this is called the bubble line. That's called the dew line. All that means is, let's say I'm at high temperature. I've got all gas. Right no coexistence, no liquid yet. And I start to cool things off. Just to where I just barely start to get liquid. What you see that as is, dew starts forming. A little bit of condensation. If you're outside, it means on the grass a little bit of dew is forming. Similarly, if I start at low temperature, all liquid now I start raising the temperature until I just start to boil. I just start to see the first bubbles forming. And so that's why these things have those names.
So now let's just follow along what happens when I do the same sort of thing that I illustrated there. I want to start at one point in this phase diagram. And then start changing the conditions. So let's start here. So I'm going to start all in the liquid phase. That is, the temperature is low. Here's xB. And my original temperature. Now I'm going to raise it. So if I raise it a little bit, I reach a point at which I first start to boil. Start to find some gas above the liquid. And if I look right here, that'll be my composition. Let me raise it a little farther, now that we've already seen the lever rule and so forth. I'll raise it up to here. And that means that out here, I suppose I should do here.
So, here is the liquid mole fraction at temperature two. xB at temperature two. This is yB at temperature two. The gas mole fraction. So as you should expect, what's going to happen here is that the gas, this is going to be lower in B. A, that means that the mole fraction of A must be higher in the gas phase. That's one minus yB. So xA is one minus -- yA, which is one minus yB higher in gas phase. Than xA, which is one minus xB. In other words, the less volatile component is enriched up in the gas phase.
Now, what does that mean? That means I could follow the same sort of procedure that I indicated before when we looked at the pressure mole fraction phase diagram. Namely, I could do this and now I could take the gas phase. Which has less of B. It has more of A. And I can collect it. And then I can reduce the temperature. So it liquefies. So I can condense it, in other words. So now I'm going to start with, let's say I lower the temperature enough so I've got basically pure liquid. But its composition is the same as the gas here. Because of course that's what that liquid is formed from. I collected the gas and separated it. So now I could start all over again. Except instead of being here, I'll be down here. And then I can raise the temperature again. To some place where I choose. I could choose here, and go all the way to hear. A great amount of enrichment. But I know from the lever rule that if I do that, I'm going to have precious little material over here. So I might prefer to raise the temperature a little more. Still get a substantial amount of enrichment. And now I've got, in the gas phase, I'll further enriched in component A. And again I can collect the gas. Condense it. Now I'm out here somewhere, I've got all liquid and I'll raise the temperature again. And I can again keep walking my way over.
And that's what happens during an ordinary distillation. Each step of the distillation walks along in the phase diagram at some selected point. And of course what you're doing is, you're always condensing the gas. And starting with fresh liquid that now is enriched in more volatile of the components. So of course if you're really purifying, say, ethanol from an ethanol water mixture, that's how you do it. Ethanol is the more volatile component. So a still is set up. It will boil the stuff and collect the gas and and condense it. And boil it again, and so forth. And the whole thing can be set up in a very efficient way. So you have essentially continuous distillation. Where you have a whole sequence of collection and condensation and reheating and so forth events. So then, in a practical way, it's possible to walk quite far along the distillation, the coexistence curve, and distill to really a high degree of purification. Any questions about how that works? OK.
I'll leave till next time the discussion of the chemical potentials. But what we'll do, just to foreshadow a little bit, what I'll do at the beginning of the next lecture is what's at the end of your notes here. Which is just to say OK, now if we look at Raoult's law, it's straightforward to say what is the chemical potential for each of the substances in the liquid and the gas phase. Of course, it has to be equal. Given that, that's for an ideal solution. We can gain some insight from that. And then look at real solutions, non-ideal solutions, and understand a lot of their behavior as well. Just from starting from our understanding of what the chemical potential does even in a simple ideal mixture. So we'll look at the chemical potentials. And then we'll look at non-ideal solution mixtures next time. See you then. | <urn:uuid:246f9a12-fd35-40fa-8257-b07bf8d92857> | CC-MAIN-2013-20 | http://ocw.mit.edu/courses/chemistry/5-60-thermodynamics-kinetics-spring-2008/video-lectures/lecture-21-ideal-solutions/ | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.963655 | 7,164 | 3.921875 | 4 |
Sleep apnea is a condition in which breathing is repeatedly interrupted during sleep. The time period for which the breathing stops or decreases is usually between 10 and 30 seconds. When these episodes occur repeatedly, sleep apnea can seriously disrupt the quality of sleep.
There are three types of respiratory events:
- Obstructive apnea—caused by a temporary, partial, or complete blockage of the airway
- Central apnea—caused by a temporary failure to make an effort to breathe
- Mixed apnea—combination of the first two types
These factors increase your chance of developing sleep apnea. Tell your doctor if you have any of these risk factors:
- Sex: male
- Large neck circumference
- Age: middle to older age
- Family history of apnea
Structural abnormalities of the nose, throat, or other part of the respiratory tract. Examples include:
- Severely enlarged tonsils
- Deviated nasal septum
- Medicines: sedatives and sleeping aids
- Alcohol consumption
- Fatigue and sleepiness during waking hours
- Loud snoring
- Breathing that stops during the night (noticed by the partner)
- Repeated waking at night
- Unrefreshing sleep
- Morning headaches
- Poor concentration or problems with memory
- Irritability or short temper
People with chronic untreated sleep apnea may be at risk for:
An overnight sleep study is used to help diagnose sleep apnea.
Overnight Sleep Study (Polysomnography)
This test helps detect the presence and severity of sleep apnea. During sleep, it measures your:
- Eye and muscle movements
- Brain activity ( electroencephalogram )
- Heart rate
- Breathing (pattern and depth)
- Percent saturation of your red blood cells with oxygen
There are a number of treatment options for sleep apnea, including:
- Lose weight if you are overweight.
- Avoid using sedatives, sleeping pills, alcohol, and nicotine, which tend to make the condition worse.
- Try sleeping on your side instead of your back.
- Place pillows strategically so you are as comfortable as possible.
- For daytime sleepiness, practice safety measures, such as avoiding driving or operating potentially hazardous equipment.
Continuous positive airway pressure (CPAP) entails wearing a mask over your nose and/or mouth during sleep. An air blower forces enough constant and continuous air through your air passages to prevent the tissues from collapsing and blocking the airway. In some cases, dental appliances that help keep the tongue or jaw in a more forward position may help.
In some cases, surgery may be recommended. It is most often beneficial in pediatric patients.
Types of surgery that may be done to treat severe cases of sleep apnea include:
- Uvulopalatopharyngoplasty—The doctor removes excess soft tissue from the nose and/or throat.
- Maxillomandibular advancement—The jawbone is repositioned forward.
- Tracheotomy —For life-threatening cases of sleep apnea, an opening is made in the windpipe to allow for normal breathing.
Bariatric surgery may help with weight loss in some people who are obese . This surgery may reduce many of the complications that are related to obesity, including sleep apnea.
Only used in central apnea, acetazolamide (Diamox) may help improve the ability to regulate breathing. Overall, there is not a lot of evidence to support the use of medicines to treat sleep apnea.
Supplemental oxygen may be given if blood levels of oxygen fall too low during sleep, even after opening the airway.
You may be able to prevent the onset of sleep apnea by maintaining a healthy weight . Avoid alcohol, nicotine, and sedatives, which may contribute to airway obstruction.
- Reviewer: Rimas Lukas, MD
- Review Date: 09/2012 -
- Update Date: 00/93/2012 - | <urn:uuid:da610566-65f7-4f92-a0b9-cbf818d8ece0> | CC-MAIN-2013-20 | http://oprmc.com/your-health/?/11549/ | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.904892 | 834 | 3.703125 | 4 |
An Introduction To 127.0.0.1
127.0.0.1 is an IP address utilized for a looplock network connection. What does this mean? If
a user tries to connect to this IP address, they will be sent back to their computer. The address
is also known as a localhost. The localhost is the computer.
How the Localhost Works
If the command is relayed to the localhost, you would be hooked up to the system where the
commands were sent out. For instance, suppose the computer is called "Joker". If you telnet
from the Joker computer to the localhost, a message will appear. It will attempt to hook up to
The localhost is employed in lieu of the computer hostname to be linked to. This IP address is
the most wisely used localhost address. However, you can actually use any IP address
provided it starts with 127. This means 127.*.*.* can be used as a localhost.
Establishing a connection with the loopback address is similar to creating a connection with
remote network computers. The only difference is you don't have to deal with network
For this reason it is widely utilized by software developers. It is also used by system
administrators. It is often used for testing programs and apps. If the connection is IPv4, the
computer's loopback address will be the 127.*.*.*. The subnet mask is typically 255.0.0.0.
This IP addresses 127.*.*.*. are defined in RFC 330 as Special-Use IPv4 Addresses. The
127.0.0.0/8 block is defined as the Net host loopback address. If a higher level protocol sends
a datagram anywhere in the block, it will be looped in the host. This is typically implemented
with the 127.0.0.1 / 32 for looplock. However, addresses in the block must not be visible
anywhere else in the network.
There is also a localhost IPv6 version. In RFC 3513, it is defined as Internet Protocol Version
6 (IPv6) Addressing Architecture::1/128.
More Information about the Localhost
In simple terms, the localhost means the computer. It is the hostname allocated loopback
network interface address. The name is likewise a domain name. This will help prevent
confusion with the hostname definition. In IPv6, the loopback IP address is ::1. The localhost
is stated when one would usually use the computer hostname. For instance, a browser using
an HTTP server to http://localhost will show the local website home page. This will be
possible if the server is set up properly to work the loopback interface.
The loopback address can also be used for linking up to a game server. It can also be used for
the various inter-process communications. This facts about 127.0.0.1 indicate how
fundamental and basic the localhost is to a system. That's why it is so crucial for network | <urn:uuid:0cfb12fb-ebfd-4e6a-8720-c551d7e97801> | CC-MAIN-2013-20 | http://pdfcast.org/pdf/a-guide-to-localhost | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.893844 | 644 | 3.8125 | 4 |
Municipal incorporation occurs when such municipalities become self-governing entities under the laws of the state or province in which they are located. Often, this event is marked by the award or declaration of a municipal charter.
With the notable exception of the City of London Corporation, the term has fallen out of favour in the United Kingdom, but the concept remains central to local government in the United Kingdom, as well as former British colonies such as India and Canada.
Municipal charters
A city charter or town charter (generically, municipal charter) is a legal document establishing a municipality such as a city or town. The concept developed in Europe during the middle ages and is considered to be a municipal version of a constitution.
Traditionally the granting of a charter gave a settlement and its inhabitants the right to town privileges under the feudal system. Townspeople who lived in chartered towns were burghers, as opposed to serfs who lived in villages. Towns were often "free", in the sense that they were directly protected by the king or emperor, and were not part of a feudal fief.
Today the process for granting charters is determined by the type of government of the state in question. In monarchies, charters are still often a royal charter given by the Crown or the state authorities acting on behalf of the Crown. In federations, the granting of charters may be within the jurisdiction of the lower level of government such as a state or province.
By country
In Brazil, municipal corporations are called municípios and are created by means of local legislation at state level, or after passing a referendum vote of the affected population. All municipal corporations must also abide by an Organic Municipal Law which is passed and amended (when needed) at municipal level.
In Canada charters are granted by provincial authorities.
In Germany, municipal corporations existed since antiquity and through medieval times, until they became out of favour during the absolutism. In order to strengthen the public spirit the city law of Prussia dated 19 November 1808 picked up this concept. It is the basis of today's municipal law.
In India a Municipal Corporation is a local government body that administers a city of population 10,00,000 or more. Under the panchayati raj system, it interacts directly with the state government, though it is administratively part of the district it is located in. The largest Municipal Corporations in India currently are Mumbai, followed by Delhi, Kolkata, Bangalore, Chennai, Hyderabad, Ahmedabad, Surat and Pune. The Corporation of Chennai is the oldest Municipal Corporation in the world outside UK.
The Municipal Corporation consists of members elected from the wards of the city. The Mayor and Deputy Mayor are elected by the public. A Municipal Commissioner, who is from the Indian Administrative Service is appointed to head the administrative staff of the Municipal Corporation, implement the decisions of the Corporation and prepare its annual budget.
The Municipal Corporation is responsible for roads, public transportation, water supply, records of births and deaths (delegated from central government Births and Deaths Registration Act), sanitation that includes waste management, sewage, drainage and flood control, public safety services like fire and ambulance services, gardens and maintenance of buildings. The sources of income of the Corporation are property tax, entertainment tax, octroi (now abolished from many cities) and usage fees for utilities.
Republic of Ireland
In Ireland, municipal corporations existed in boroughs since medieval times. The Corporation of Dublin, officially styled the Right Honourable the Lord Mayor, Aldermen, and Burgesses of the City of Dublin had existed since the 13th century. Corporations were established under the royal charter establishing the city or borough. The Municipal Corporations (Ireland) Act 1840 abolished all but ten of the boroughs and their corporations. The Local Government (Ireland) Act 1898 created two different types of borough, county boroughs had essentially equal status to counties - these comprised Dublin, Cork, Limerick, and Waterford (as well as Belfast and Derry, which are now in Northern Ireland). The other boroughs were non-county boroughs.
The Local Government Act 2001 abolished the title of municipal corporation. Corporations of county boroughs (renamed cities) were renamed City Councils. Non county boroughs were abolished, but those towns which were previously non-county boroughs were allowed to use the title of Borough Council. Royal charters remain in force for ceremonial and civic purposes only.
South Africa
From the beginning of American colonial rule, Philippines cities were formally established through laws enacted by the various national legislatures in the country. The Philippine Commission gave the city of Manila its charter in 1901, while the city of Baguio was established by the Philippine Assembly which was composed by elected members instead of appointed ones. During the Commonwealth era, the National Assembly established an additional ten cities. Since achieving independence from the United States in 1946 the Philippine Congress has established 124 more cities (as of September 2007), the majority of which required the holding of a plebiscite within the proposed city's jurisdiction to ratify the city's charter.
United Kingdom
United States
In the United States, such municipal corporations are established by charters that are granted either directly by a state legislature by means of local legislation, or indirectly under a general municipal corporation law, usually after the proposed charter has passed a referendum vote of the affected population. | <urn:uuid:ff2d2b6b-aa78-4bda-ba69-e90f18d28bfb> | CC-MAIN-2013-20 | http://pediaview.com/openpedia/Municipal_corporation | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.969311 | 1,116 | 4.09375 | 4 |
Researchers at UT Southwestern Medical Center have found that fluctuations in internal body temperature regulate the body's circadian rhythm, the 24-hour cycle that controls metabolism, sleep and other bodily functions.
A light-sensitive portion of the brain called the suprachiasmatic nucleus (SCN) remains the body's "master clock" that coordinates the daily cycle, but it does so indirectly, according to a study published by UT Southwestern researchers in the Oct. 15 issue of Science.
The SCN responds to light entering the eye, and so is sensitive to cycles of day and night. While light may be the trigger, the UT Southwestern researchers determined that the SCN transforms that information into neural signals that set the body's temperature. These cyclic fluctuations in temperature then set the timing of cells, and ultimately tissues and organs, to be active or inactive, the study showed.
Scientists have long known that body temperature fluctuates in warm-blooded animals throughout the day on a 24-hour, or circadian, rhythm, but the new study shows that temperature actually controls body cycles, said Dr. Joseph Takahashi, chairman of neuroscience at UT Southwestern and senior author of the study.
"Small changes in body temperature can send a powerful signal to the clocks in our bodies," said Dr. Takahashi, an investigator with the Howard Hughes Medical Institute. "It takes only a small change in internal body temperature to synchronize cellular 'clocks' throughout the body."
Daily changes in temperature span only a few degrees and stay within normal healthy ranges. This mechanism has nothing to do with fever or environmental temperature, Dr. Takahashi said.
This system might be a modification of an ancient circadian control system that first developed in other organisms, including cold-blooded animals, whose daily biological cycles are affected by external temperature changes, Dr. Takahashi said.
"Circadian rhythms in plants, simple organisms and cold-blooded animals are very sensitive to temperature, so it makes sense that over the course of evolution, this primordial mechanism could have been modified in warm-blooded animals," he said.
In the current study, the researchers focused on cultured mouse cells and tissues, and found that genes related to circadian functions were controlled by temperature fluctuations.
SCN cells were not temperature-sensitive, however. This finding makes sense, Dr. Takahashi said, because if the SCN, as the master control mechanism, responded to temperature cues, a disruptive feedback loop could result, he said.
Explore further: Now we know why old scizophrenia medicine works on antibiotics-resistant bacteria | <urn:uuid:896eff09-96fc-4a88-806f-0afe2beec059> | CC-MAIN-2013-20 | http://phys.org/news/2010-10-temperature-rhythms-body-clocks-sync.html | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.936214 | 528 | 3.671875 | 4 |
File compression is to perform some algorithm on the file that reduces it in size but the reverse of the algorithm will return it to its original form. In data files, the compression and decompression must be lossless which means that the data must be returned to its exact form. There are various methods to do this: some hardware implementations and some software. The most popular ones that are implemented in hardware usually use a Limpel-Ziv algorithm to look for repeating sequences over a set span of data (the run) and replace that with special identifying information. Compression does save space but may take extra time (latency).
Video and music data are typically already compressed. The compression rates are usually very high because of the data and the fact that a lossy compression algorithm is used. It can be lossy (meaning that all bits may not be decompressed exactly) because it won't be noticeable with video or music.
Zip files are the result of software compression. Another compression round on already compressed data will probably not yield any substantial gain.
Evaluator Group, Inc.
Editor's note: Do you agree with this expert's response? If you have more to share, post it in our Storage Networking forum at http://searchstorage.discussions.techtarget.com/WebX?50@@.ee83ce4 or e-mail us directly at [email protected].
This was first published in December 2001 | <urn:uuid:89cf800c-2b77-4614-98f0-40e3877e109f> | CC-MAIN-2013-20 | http://searchstorage.techtarget.com/answer/What-is-compression | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.931701 | 295 | 3.75 | 4 |
Classroom Activities for Teaching Sedimentary GeologyThis collection of teaching materials allows for the sharing of ideas and activities within the community of geoscience teachers. Do you have a favorite teaching activity you'd like to share? Please help us expand this collection by contributing your own teaching materials.
Subject: Sedimentary Geology
Results 1 - 4 of 4 matches
Chemical and Physical Weathering Field and Lab Experiment: Development and Testing of Hypotheses part of Activities
Lisa Greer, Washington and Lee University
This exercise combines an integrated field and laboratory experiment with a significant scientific writing assignment to address chemical and physical weathering processes via hypothesis development, experimental ...
Demystifying the Equations of Sedimentary Geology part of Activities
Larry Lemke, Wayne State University
This activity includes three strategies to help students develop a deeper comfort level and stronger intuitive sense for understanding mathematical expressions commonly encountered in sedimentary geology. Each can ...
Digital Sandstone Tutorial part of Activities
Kitty Milliken, University of Texas at Austin, The
The Tutorial Petrographic Image Atlas is designed to give students more exposure to petrographic features than they can get during organized laboratory periods.
Red rock and concretion models from Earth to Mars: Teaching diagenesis part of Activities
Margie Chan, University of Utah
This activity teaches students concepts of terrestrial diagenesis (cementation, fluid flow, porosity and permeability, concretions) and encourages them to apply those concepts to new or unknown settings, including ... | <urn:uuid:f4b8146e-83a2-43e4-8f2c-b3c235ae8afb> | CC-MAIN-2013-20 | http://serc.carleton.edu/NAGTWorkshops/sedimentary/activities.html?q1=sercvocabs__43%253A206 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.898655 | 310 | 3.875 | 4 |
- Exam wrappers. As David Thompson describes the process, "exam wrappers required students to reflect on their performance before and after seeing their graded tests." The first four questions, completed just prior to receiving their graded test, asked students to report the time they spent preparing for the test, their methods of preparation, and their predicted test grade. After reviewing their graded test, students completed the final three reflection questions, including a categorization of test mistakes and a list of changes to implement in preparation for the next test. Thompson then collected and made copies of the wrappers returned them to the students several days later, reminding them to consider what they planned to do differently or the same in preparation for the upcoming test. Thompson reports that each reflection exercise required only 8-10 minutes of class time. Clara Hardy and others also describes uses exam wrappers.
- Reading Reflections. As Karl Wirth writes, reading reflections, effectively outlined by David Bressoud (2008), are designed to address some of the challenges students face with college-level reading assignments. Students submit online reading reflections (e.g., using Moodle or Blackboard) after completing each reading assignment and before coming to class. In each reflection, students summarize the important concepts of the reading and describe what was interesting, surprising, or confusing to them. The reading reflections not only encourage students to read regularly before class, but they also promote content mastery and foster student development of monitoring, self-evaluation, and reflection skills. For the instructor, reading reflections facilitate "just-in-time" teaching and provide invaluable insights into student thinking and learning. According to Wirth, expert readers are skilled at using a wide range of strategies during all phases of reading (e.g., setting goals for learning, monitoring comprehension during reading, checking comprehension, and self-reflection), but most college instruction simply assumes the mastery of such metacognitive skills.
- Knowledge surveys. Many members of the group were influenced by Karl Wirth's work on "knowledge surveys" as a central strategy for helping students think about their thinking. Knowledge surveys involve simple self-reports from students about their knowledge of course concepts and content. In knowledge surveys, students are presented with different facets of course content and are asked to indicate whether they know the answer, know some of the answer, or don't know the answer. Faculty can use these reports to gauge how confident students feel in their understanding of course material at the beginning or end of a course, before exams or papers, or even as graduating seniors or alumni.
Kristin Bonnie's report relates how her students completed a short knowledge survey (6-12 questions) online (via Google forms) on the material covered in class that week. Rather than providing the answer to each question, students indicated their confidence in their ability to answer the question correctly (I know; I think I know; I don't know). Students received a small amount of credit for completing the knowledge survey. She used the information to review material that students seemed to struggle with. In addition, a subset of these questions appeared on their exam – the knowledge survey therefore served as a review sheet.Wirth notes that the surveys need not take much class time and can be administered via paper or the web. The surveys can be significant for clarifying course objectives, structure, and design. For students, knowledge surveys achieve several purposes: they help make clear course objectives and expectations, are useful as study guides, can serve as a formative assessment tool, and, perhaps most critically, aid in their development of self-assessment and metacognitive skills. For instructors, the surveys help them assess learning gains, instructional practices, and course design. | <urn:uuid:9d6abf05-e21c-4917-ab95-cb9f3fd306aa> | CC-MAIN-2013-20 | http://serc.carleton.edu/acm_teagle/interventions | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.956848 | 746 | 3.578125 | 4 |
Mercury in the Morning
The planet Mercury -- the planet closest to the Sun -- is just peeking into view in the east at dawn the next few days. It looks like a fairly bright star. It's so low in the sky, though, that you need a clear horizon to spot it, and binoculars wouldn't hurt.
Mercury is a bit of a puzzle. It has a big core that's made mainly of iron, so it's quite dense. Because Mercury is so small, the core long ago should've cooled enough to form a solid ball. Yet the planet generates a weak magnetic field, hinting that the core is still at least partially molten.
The solution to this puzzle may involve an iron "snow" deep within the core.
The iron in the core is probably mixed with sulfur, which has a lower melting temperature than iron. Recent models suggest that the sulfur may have kept the outer part of the core from solidifying -- it's still a hot, thick liquid.
As this mixture cools, though, the iron "freezes" before the sulfur does. Small bits of solid iron fall toward the center of the planet. This creates convection currents -- like a pot of boiling water. The motion is enough to create a "dynamo" effect. Like a generator, it produces electrical currents, which in turn create a magnetic field around the planet.
Observations earlier this year by the Messenger spacecraft seem to support that idea. But Messenger will provide much better readings of what's going on inside Mercury when it enters orbit around the planet in 2011.
Script by Damond Benningfield, Copyright 2008
For more skywatching tips, astronomy news, and much more, read StarDate magazine. | <urn:uuid:d0a1999f-a775-4afc-bcfd-ee6ff6243a0b> | CC-MAIN-2013-20 | http://stardate.org/radio/program/2008-10-20 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.943661 | 357 | 4 | 4 |
The Gram-Schmidt Process
Now that we have a real or complex inner product, we have notions of length and angle. This lets us define what it means for a collection of vectors to be “orthonormal”: each pair of distinct vectors is perpendicular, and each vector has unit length. In formulas, we say that the collection is orthonormal if . These can be useful things to have, but how do we get our hands on them?
It turns out that if we have a linearly independent collection of vectors then we can come up with an orthonormal collection spanning the same subspace of . Even better, we can pick it so that the first vectors span the same subspace as . The method goes back to Laplace and Cauchy, but gets its name from Jørgen Gram and Erhard Schmidt.
We proceed by induction on the number of vectors in the collection. If , then we simply set
This “normalizes” the vector to have unit length, but doesn’t change its direction. It spans the same one-dimensional subspace, and since it’s alone it forms an orthonormal collection.
Now, lets assume the procedure works for collections of size and start out with a linearly independent collection of vectors. First, we can orthonormalize the first vectors using our inductive hypothesis. This gives a collection which spans the same subspace as (and so on down, as noted above). But isn’t in the subspace spanned by the first vectors (or else the original collection wouldn’t have been linearly independent). So it points at least somewhat in a new direction.
To find this new direction, we define
This vector will be orthogonal to all the vectors from to , since for any such we can check
where we use the orthonormality of the collection to show that most of these inner products come out to be zero.
So we’ve got a vector orthogonal to all the ones we collected so far, but it might not have unit length. So we normalize it:
and we’re done. | <urn:uuid:4a2ad899-7ba0-4bfc-9276-c5c5c0845fe6> | CC-MAIN-2013-20 | http://unapologetic.wordpress.com/2009/04/28/the-gram-schmidt-process/?like=1&source=post_flair&_wpnonce=fe7f791e1e | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.897189 | 447 | 3.625 | 4 |
Attention Deficit Hyperactivity Disorder or ADHD is a common childhood illness. People who are affected can have trouble with paying attention, sitting still and controlling their impulses. There are three types of ADHD. The most common type of ADHD is when people have difficulties with both attention and hyperactivity. This is called ADHD combined type. Some people only have difficulty with attention and organization. This is ADHD inattentive subtype or Attention Deficit Disorder (ADD). Other people have only the hyperactive and impulsive symptoms. This is ADHD hyperactive subtype.
It is a health condition involving biologically active substances in the brain. Studies show that ADHD may affect certain areas of the brain that allow us to solve problems, plan ahead, understand others' actions, and control our impulses.
Many children and adults are easily distracted at times or have trouble finishing tasks. If you suspect that your child has ADHD, it is important to have your child evaluated by his or her doctor. In order for your child’s doctor to diagnose your child with ADHD, the behaviors must appear before age 7 and continue for at least six months. The symptoms must also create impairment in at least two areas of the child's life-in the classroom, on the playground, at home, in the community, or in social settings. Many children have difficulties with their attention but attention problems are not always cue to ADHD. For example, stressful life events and other childhood conditions such as problems with schoolwork caused by a learning disability or anxiety and depression can interfere with attention.
According to the National Institute of Mental Health, ADHD occurs in an estimated 3 to 5 percent of preschool and school-age children. Therefore, in a class of 25 to 30 children, it is likely that at least one student will have this condition. ADHD begins in childhood, but it often lasts into adulthood. Several studies done in recent years estimate that 30 to 65 percent of children with ADHD continue to have symptoms into adolescence and adulthood.
No one knows exactly what causes ADHD. There appears to be a combination of causes, including genetics and environmental influences Several different factors could increase a child's likelihood of having the disorder, such as gender, family history, prenatal risks, environmental toxins and physical differences in the brain seem to be involved.
A child with ADHD often shows some of the following:
Difficulties with attention:
- trouble paying attention
- inattention to details and makes careless mistakes
- easily distracted
- losing things such as school supplies
- forgetting to turn in homework
- trouble finishing class work and homework
- trouble listening
- trouble following multiple adult commands
- difficulty playing quietly
- inability to stay seated
- running or climbing excessively
- always "on the go"
- talks too much and interrupts or intrudes on others
- blurts out answers
The good news is that effective treatment is available. The first step is to have a careful and thorough evaluation with your child’s primary care doctor or with a qualified mental health professional. With the right treatment, children with ADHD can improve their ability to pay attention and control their behavior. The right care can help them grow, learn, and feel better about themselves.
Medications: Most children with ADHD benefit from taking medication. Medications do not cure ADHD. Medications can help a child control his or her symptoms on the day that the pills are taken.
Medications for ADHD are well established and effective. There are two main types: stimulant and non-stimulant medications. Stimulants include methylphenidate, and amphetamine salts. Non-stimulant medications include atomoxetine. For more information about the medications used to treat ADHD, please see the Parent Med Guide. Before medication treatment begins, your child's doctor should discuss the benefits and the possible side effects of these medications. Your child’s doctor should continue to monitor your child for improvement and side effects. A majority of children who benefit from medication for ADHD will continue to benefit from it as teenagers. In fact, many adults with ADHD also find that medication can be helpful.
Therapy and Other Support: A psychiatrist or other qualified mental health professional can help a child with ADHD. The psychotherapy should focus on helping parents provide structure and positive reinforcement for good behavior. In addition, individual therapy can help children gain a better self-image. The therapist can help the child identify his or her strengths and build on them. Therapy can also help a child with ADHD cope with daily problems, pay better attention, and learn to control aggression.
A therapist may use one or more of the following approaches: Behavior therapy, Talk therapy, Social skills training, Family support groups.
Sometimes children and parents wonder when children can stop taking ADHD medication. If you have questions about stopping ADHD medication, consult your doctor. Many children diagnosed with ADHD will continue to have problems with one or more symptoms of this condition later in life. In these cases, ADHD medication can be taken into adulthood to help control their symptoms.
For others, the symptoms of ADHD lessen over time as they begin to "outgrow" ADHD or learn to compensate for their behavioral symptoms. The symptom most apt to lessen over time is hyperactivity.
Some signs that your child may be ready to reduce or stop ADHD medication are:
- Your child has been symptom-free for more than a year while on medication,
- Your child is doing better and better, but the dosage has stayed the same,
- Your child's behavior is appropriate despite missing a dose or two,
- Or your child has developed a newfound ability to concentrate.
The choice to stop taking ADHD medication should be discussed with the prescribing doctor, teachers, family members, and your child. You may find that your child needs extra support from teachers and family members to reinforce good behavior once the medication is stopped.
Without treatment, a child with ADHD may fall behind in school and have trouble with friendships. Family life may also suffer. Untreated ADHD can increase strain between parents and children. Parents often blame themselves when they can't communicate with their child. The sense of losing control can be very frustrating. Teenagers with ADHD are at increased risk for driving accidents. Adults with untreated ADHD have higher rates of divorce and job loss, compared with the general population. Luckily, safe and effective treatments are available which can help children and adults help control the symptoms of ADHD and prevent the unwanted consequences. | <urn:uuid:40aae48c-b422-4ff3-a8dc-88f9431d1a4e> | CC-MAIN-2013-20 | http://www.aacap.org/cs/ADHD.ResourceCenter/adhd_faqs | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.959207 | 1,307 | 3.71875 | 4 |
Arctic meltdown not caused by nature
Rapid loss of Arctic sea ice - 80 per cent has disappeared since 1980 - is not caused by natural cycles such as changes in the Earth's orbit around the Sun, says Dr Karl.
The situation is getting rather messy with regard to the ice melting in the Arctic. Now the volume of the ice varies throughout the year, rising to its peak after midwinter, and falling to its minimum after midsummer, usually in the month of September.
Over most of the last 1,400 years, the volume of ice remaining each September has stayed pretty constant. But since 1980, we have lost 80 per cent of that ice.
Now one thing to appreciate is that over the last 4.7 billion years, there have been many natural cycles in the climate — both heating and cooling. What's happening today in the Arctic is not a cycle caused by nature, but something that we humans did by burning fossil fuels and dumping slightly over one trillion tonnes of carbon into the atmosphere over the last century.
So what are these natural cycles? There are many many of them, but let's just look at the Milankovitch cycles. These cycles relate to the Earth and its orbit around the Sun. There are three main Milankovitch cycles. They each affect how much solar radiation lands on the Earth, and whether it lands on ice, land or water, and when it lands.
The first Milankovitch cycle is that the orbit of the Earth changes from mostly circular to slightly elliptical. It does this on a predominantly 100,000-year cycle. When the Earth is close to the Sun it receives more heat energy, and when it is further away it gets less. At the moment the orbit of the Earth is about halfway between "nearly circular" and "slightly elliptical". So the change in the distance to the Sun in each calendar year is currently about 5.1 million kilometres, which translates to about 6.8 per cent difference in incoming solar radiation. But when the orbit of the Earth is at its most elliptical, there will be a 23 per cent difference in how much solar radiation lands on the Earth.
The second Milankovitch cycle affecting the solar radiation landing on our planet is the tilt of the north-south spin axis compared to the plane of the orbit of the Earth around the Sun. This tilt rocks gently between 22.1 degrees and 24.5 degrees from the vertical. This cycle has a period of about 41,000 years. At the moment we are roughly halfway in the middle — we're about 23.44 degrees from the vertical and heading down to 22.1 degrees. As we head to the minimum around the year 11,800, the trend is that the summers in each hemisphere will get less solar radiation, while the winters will get more, and there will be a slight overall cooling.
The third Milankovitch cycle that affects how much solar radiation lands on our planet is a little more tricky to understand. It's called 'precession'. As our Earth orbits the Sun, the north-south spin axis does more than just rock gently between 22.1 degrees and 24.5 degrees. It also — very slowly, just like a giant spinning top — sweeps out a complete 360 degrees circle, and it takes about 26,000 years to do this. So on January 4, when the Earth is at its closest to the Sun, it's the South Pole (yep, the Antarctic) that points towards the Sun.
So at the moment, everything else being equal, it's the southern hemisphere that has a warmer summer because it's getting more solar radiation, but six months later it will have a colder winter. And correspondingly, the northern hemisphere will have a warmer winter and a cooler summer.
But of course, "everything else" is not equal. There's more land in the northern hemisphere but more ocean in a southern hemisphere. The Arctic is ice that is floating on water and surrounded by land. The Antarctic is the opposite — ice that is sitting on land and surrounded by water. You begin to see how complicated it all is.
We have had, in this current cycle, repeated ice ages on Earth over the last three-million years. During an ice age, the ice can be three kilometres thick and cover practically all of Canada. It can spread through most of Siberia and Europe and reach almost to where London is today. Of course, the water to make this ice comes out of the ocean, and so in the past, the ocean level has dropped by some 125 metres.
From three million years ago to one million years ago, the ice advanced and retreated on a 41,000-year cycle. But from one million years ago until the present, the ice has advanced and retreated on a 100,000-year cycle.
What we are seeing in the Arctic today — the 80 per cent loss in the volume of the ice since 1980 — is an amazingly huge change in an amazingly short period of time. But it seems as though the rate of climate change is accelerating, and I'll talk more about that, next time …
Published 27 November 2012
© 2013 Karl S. Kruszelnicki Pty Ltd | <urn:uuid:3a4ac59c-d59d-470b-adad-88e5e1c8a45a> | CC-MAIN-2013-20 | http://www.abc.net.au/science/articles/2012/11/27/3640992.htm?topic=latest | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz | en | 0.955824 | 1,065 | 3.5625 | 4 |
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