The principle of the ABO system is that antigens – in this instance, sugars exposed on the surface of red blood cells – differ between individuals. This first discovered by Karl Landsteiner. People have immunological tolerance only for what occurs in their own bodies. As a result, humans may produce antibodies against natural components in the bodies of "other" people, but not themselves. So, people may produce antibodies against A and/or B antigens if they are not in their blood.
These antibodies clump red blood cells together if they carry the foreign antigens. This harsh response can cause death when large amounts of such cells are encountered after a blood transfusion. Because A and B antigens are chemically modified from a precursor form that is also present in type O individuals, people with type A and B antigens can accept blood from type O individuals.
Anti-A and anti-B antibodies are not present in the newborn. They appear in the first years of life. Anti-A and anti-B antibodies are usually too big to pass through the placenta to the foetal blood circulation.
In a laboratory, blood is tested for antigens. When a certain antigen is found, there are also always antibodies found. Antibodies attack (attach to) antigens that they do not recognise.
The blood is thus tagged as being "A positive", "O negative" for instance, where the letter refers to the ABO blood group and "positive" or "negative" refers to whether or not the RhD-antigen of the Rhesus blood group system was found. It can also be written "A+ " and "O-", respectively.
People with type O negative blood are often called universal donors because they can give blood to any other blood group. People with type AB positive blood are called universal recipients because they can receive blood from any other blood group.
The Rh factor (Rh meaning Rhesus) is a feature of the second most common blood-group system in human-blood transfusion. it is named after the Rhesus monkey where they were first discovered. Rh is an inherited trait, which refers to a protein on the surface of an individual's red blood cells.
The Rh factor is separate from, and in addition to, ABO groups. The Rh factor is either present on individual's red blood cells or it is not. Rh positive means the factor is present. Rh negative means it is not present. In blood transfusions it is important that the blood donor and recipient have the same Rh factor and same blood group.
Before a transfusion takes place blood is thoroughly tested for anything that might cause problems for the receiver.
Trance music
Trance music is a kind of electronic music. It centers around a synthesizer and bass drum on each beat and melodies with themes. Most trance music usually have 140 beats per minute. Trance music is commonly played in clubs. The genre takes insipiration from techno, house music, and other kinds of electronic music.
Trance refers to an altered state of consciousness as, for example, achieved by hypnosis. Trance music is characterised by unusually long tracks of highly repetitious music. Group dancing makes the effect stronger, as it does with some types of traditional African music. The general idea has been many times used in religious ceremonies. Nobody knows who introduced the term to electronic music.
Acuminite
Acuminite is a colorless mineral made from crystals. It is named for the Latin word "acuminis" (meaning "sharp point" or "spearhead") for the way the crystals are made. It is easily found in Greenland in the Ivigtut cryolite deposit. It is easily scratched with a copper penny.
Warthog
Warthog ("Phacochoerus africanus") are remarkable animals. They are found in most of Africa south of the Sahara and are widely distributed in East Africa. They are the only pigs able to live in areas without water for several months of the year. By tolerating a higher-than-normal body temperature, the warthog is perhaps able to conserve moisture inside its body that might otherwise be used for cooling. (Camels and desert gazelles have developed a similar mechanism for survival in hot, arid environments.)
Warthogs are found in moist and arid savannas. They avoid rainforest, deserts and high mountains.
Moraine
Moraines are accumulations of debris that are found in regions where there are glaciers or were glaciers formerly.
Moraines which are found far off from existing glaciers were created during a past ice age. The debris may have been taken off the valley floor as a glacier moved or fallen off the valley walls as a result of weathering. Moraines may be made of silt like glacial flour to large boulders. Moraines may be on the glacier’s surface or deposited as piles or sheets of debris where the glacier has melted. Moraines may also develop when a glacier or iceberg reaches the sea and melts, dropping rocks that it has carried.
Silt
Silt is soil or rock that developed from granular material of a specific grain size.
Silty soil has much smaller particles than sandy soil so it’s smooth to the touch. When moistened, it’s soapy slick. When you roll it between your fingers, dirt is left on your skin.
Silty soil retains water longer, but it can’t hold on to as much nutrients as you’d want it to though it’s fairly fertile. Due to its moisture-retentive quality, silty soil is cold and drains poorly.
Silt particles range between a and mm (3.9 to 62.5 μm), larger than clay but smaller than a sand. Silt is chemically distinct from clay, and unlike clay, grains of silt are about the same size in all dimensions.
Silt may occur as a soil or alternatively as suspended sediment in a water column of any surface water body. It may also exist as deposition soil at the bottom of a water body after it is eroded elsewhere and transported by a stream or by a current. Silt is easily transported in water and is fine enough to be carried long distances by air as 'dust'. Thick deposits of silty material that result from "wind" deposition are often called "loess" (a German term) or "limon" (French). Silt and clay contribute to in water.
Silt (disambiguation)
Silt is a type of soil or earth material. It may also refer to:
Catalytic converter
A catalytic converter is a device in the exhaust pipe of a car, near its engine. It is used to clean up the exhaust the car sends out into the atmosphere. It works by using a catalyst material, usually made of Platinum, Palladium, and Rhodium. The catalytic converter converts carbon monoxide, hydrocarbons, and nitrogen oxides, all of which make the air dirty and make people sick, into carbon dioxide, water, and Nitrogen, all of which are less harmful. These chemicals, however, are still large contributors to global warming. A catalytic converter reduces carbon monoxide by contacting it with oxygen, creating carbon dioxide, which is less harmful. Because hydrocarbons are unburned fuel particles that are put into the catalytic converter, they burn up in the catalytic converter, making it very hot.
Adamite
Adamite is a mineral that can be either yellow, purple, green, pink, or yellowish-green in color and is made from crystals. It is very easy to break and it can be scratched by a copper penny. Adamite is not radioactive. It is named for the French mineralogist Gilbert Joseph Adam (1795-1881), who was the person who discovered it. It is mainly found in the Atacama Desert in Chile. Adamite is also used for other commercial resources.
Six Flags Great Adventure
Six Flags Great Adventure is a theme park in Jackson Township, New Jersey, United States. It opened on July 4, 1974. The park complex also contains the Hurricane Harbor water park.