11 résultats pour "bind"
- double-bind.
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Immune System.
The humoral immune response involves a complex series of events after antigens enter the body. First, macrophages take up some of the antigen and attach it to classII MHC molecules, which then present the antigen to T helper cells. The T helper cells bind the presented antigen, which stimulates the T helper cells to divide andsecrete stimulatory molecules called interleukins. The interleukins in turn activate any B lymphocytes that have also bound the antigen. The activated B cells then divide...
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Quark
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INTRODUCTION
Quark, smallest known building block of matter.
Constituents of MatterMatter is composed of tiny particles called quarks. Quarks come in six varieties: up (u), down (d), charm (c), strange (s),top (t), and bottom (b). Quarks also have antimatter counterparts called antiquarks (designated by a line over the lettersymbol). Quarks combine to form larger particles called baryons, and quarks and antiquarks combine to form mesons.Protons and neutrons, particles that form the nuclei of atoms, are examples of baryons. Positive and negative kaons aree...
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Neutron
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INTRODUCTION
Neutron, electrically neutral elementary particle that is part of the nucleus of the atom.
Beta DecayBeta decay can occur in two ways. As shown on the left, a neutron turns into a proton by emitting an antineutrino and anegatively charged beta particle. As shown on the right, a proton turns into a neutron by emitting a neutrino and apositively charged beta particle. Positive beta particles are called positrons and negative beta particles are called electrons.After the decay, the nucleus of the atom contains either one less or one more proton. Beta decay changes an atom of oneelement i...
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Jérôme Binde reproche 'aux jeunes un idéal sans ambition, modeste, sans grand dessein,
qui se résume aux trois mots «cœur,...
Jérôme Binde reproche 'aux jeunes un idéal sans ambition, modeste, sans grand dessein, qui se résume aux trois mots «cœur, chaumière et compte en banque». Ce souci de tranquillité nie tout esprit d'aventure. Certes, la passion amoureuse constitue à elle seule une aventure si l'on imagine que celle-ci s'accompagne de souffrances, de risques et d'émotions. Mais il est évident que le contexte fait référence à un sentiment plus paisible et presque douceâtre, bien éloigné de l'errant qui, dans sa cou...
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Hormone.
women is called a follicle-stimulating hormone. When a follicle-stimulating hormone binds to an ovary cell, it stimulates the enzymes needed for the synthesis ofestradiol, a female sex hormone. Another gonadotropin called luteinizing hormone regulates the production of eggs in women and the production of the male sexhormone testosterone. Produced in the male gonads, or testes, testosterone regulates changes to the male body during puberty, influences sexual behavior, and playsa role in growth. T...
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Eiskunstlauf: Weltmeister.
1992 Wiktor Petrenko, CIS Kurt Browning, CAN Elvis Stojko, CAN 1993 Kurt Browning, CAN Elvis Stojko, CAN Alexej Urmanow, RUS 1994 Elvis Stojko, CAN Philippe Candeloro, FRA Wjatscheslaw Sagorodnjuk, UKR 1995 Elvis Stojko, CAN Todd Eldredge, USA Philippe Candeloro, FRA 1996 Todd Eldredge, USA Ilja Kulik, RUS Rudy Galindo, USA 1997 Elvis Stojko, CAN Todd Eldredge, USA Alexej Jagudin, RUS 1998 Alexej Jagudin, RUS Todd Eldredge, USA Jewgeni Pljuschtschenko, RUS 1999 Alexej Jagudin, RUS Jewgeni Pljusc...
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Virus (life science) - biology.
RNA into DNA earned them their name because this process is the reverse of the usual transfer of genetic information, from DNA to RNA.) The DNA form of theretrovirus genome is then integrated into the cellular DNA and is referred to as the provirus. The viral genome is replicated every time the host cell replicates its DNA and is thus passed on to daughter cells. Hepatitis B virus can also transcribe RNA to DNA, but this virus packages the DNA version of its genome into virus particles. Unlike...
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Physics
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INTRODUCTION
Physics, major science, dealing with the fundamental constituents of the universe, the forces they exert on one another, and the results produced by these forces.
Starting about 1665, at the age of 23, Newton enunciated the principles of mechanics, formulated the law of universal gravitation, separated white light into colors,proposed a theory for the propagation of light, and invented differential and integral calculus. Newton's contributions covered an enormous range of naturalphenomena: He was thus able to show that not only Kepler's laws of planetary motion but also Galileo's discoveries of falling bodies follow a combination of his ownsecond law of m...
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Hazardous Wastes.
A Source Reduction The best way to eliminate hazardous wastes is not to generate them in the first place. For example, improvements have been made in the production of integratedcircuits: The toxic chlorinated hydrocarbons commonly used in the 1970s were replaced in the 1980s by less toxic glycol ethers and in the 1990s by low-toxicity estersand alcohols. B Recycling Recycling is the recovery or reuse of usable materials from waste. About 5 percent of hazardous waste in the United States is re...
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Genetics - biology.
construct identical buildings. Just as each contractor would require a full copy of the blueprint to construct a complete building, each new cell needs a complete copy ofan organism’s genetic information to function properly. Organisms use two types of cell division to ensure that DNA is passed down from cell to cell during reproduction. Simple one-celled organisms and other organisms thatreproduce asexually—that is, without the joining of cells from two different organisms—reproduce by a proces...