plasma (redirected from antihemophilic human plasma)

plasma, in physics, fully ionized gas of low density, containing approximately equal numbers of positive and negative ions (see electron and ion). It is electrically conductive and is affected by magnetic fields. The study of plasma, called plasma physics, is especially important in research efforts to produce a controlled thermonuclear reaction (see nuclear energy). Such a reaction requires extremely high temperatures; it has been computed that a temperature of about 10 million degrees Celsius would be needed to initiate the reaction between deuterium and tritium. By passing a very high electric current through plasma great heat is produced and, simultaneously, an electromagnetic field is created, causing the plasma to withdraw from the walls of its container. The contraction of the plasma, called the pinch effect, prevents the container from being destroyed, but the effect may become unstable too quickly for the fusion reaction. The properties of plasma are distinct from those of the ordinary states of matter, and for this reason many scientists consider plasma a fourth state of matter. Interstellar gases, as well as the matter inside stars, are thought to be in the form of plasma, thus making plasma a common form of matter in the universe. See also condensate.

---

plasma

Liquid part of blood (including dissolved chemicals but not the cells and platelets). This straw-coloured fluid serves as the blood's transport medium, helps maintain blood pressure, distributes body heat, and maintains the pH balance in the bloodstream and body. More than 90% consists of water, about 7% proteins, and the rest other substances, including waste products of metabolism. Important plasma proteins include albumin, coagulation factors, and globulins, including gamma globulin and a hormone that stimulates erythrocyte formation. Serum is the liquid part of the blood that remains after clotting.

---

plasma

Electrically conducting medium in which there are roughly equal numbers of positively and negatively charged particles, produced when the atoms in a gas become ionized (see ionization). Plasma is sometimes called the fourth state of matter (the first three being solid, liquid, and gas). A plasma is unique in the way it interacts with itself, with electric and magnetic fields, and with its environment. It can be thought of as a collection of ions, electrons, neutral atoms and molecules, and photons in which some atoms are being ionized at the same time as electrons are recombining with other ions to form neutral particles, while photons are continuously being produced and absorbed. It is estimated that more than 99% of the matter in the universe exists in the plasma state.

---

One of four states of matter (solid, liquid, plasma and gas). The plasma state is a gas that is heated to the point where it begins to release electrons. Although plasma occurs naturally on the sun and other stars, it is artificially produced in fluorescent lights and plasma displays by electrically charging a gas in order to release ultraviolet light. See plasma display and flat panel TV.

---

PLASMA - PLAnner-like System Modelled on Actors. Carl Hewitt, 1975. The first actor language. Originally called Planner-73, and implemented in MacLisp. Lisp-like syntax, but with several kinds of parentheses and brackets. ["A PLASMA Primer", B. Smith et al, AI Lab Working Paper 92, MIT Oct 1975]. ["Viewing Control Structures as Patterns of Passing Messages", C. Hewitt, AI Lab Memo 410, MIT 1976].