2. In chemistry, a prefix to indicate isomeric variety or position in compounds of substituted groups.
3. The second of any series, or a second item in a series or system of classification; such as, in chemistry, astronomy, botany, physics, etc.
4. A mathematical measure of the sensitivity of rates of return on a portfolio or a given stock compared with rates of return on the stock market as a whole.
A beta of 1.0 indicates that an asset closely follows the market; a beta greater than 1.0 indicates greater volatility than the market.5. The second position from a designated carbon atom in an organic molecule at which an atom or a radical may be substituted.
6. In computer science, a beta version or beta test; the final stage in the testing of new software before its commercial release, conducted by testers other than its developers.
2. A carotenoid precursor of vitamin A found in many fresh vegetables and fruits; an antioxidant that minimizes the damage caused by free radicals.
2. Any of the basophilic chromophil cells located in the anterior lobe of the pituitary gland.
One of the 20 brightest stars with 0.86 magnitude.
Beta decay is the disintegration of the nucleus of an atom to produce a beta particle, or high-speed electron, and an electron-antineutrino.
During beta decay a neutron in the nucleus changes into a proton, thereby increasing the atomic number by one while the mass number stays the same.
2. A small electrically charged particle thrown off by many radio-active materials.
It is identical to the electron and possesses the smallest negative electric charge found in nature.
Beta particles emerge from radioactive material at high speeds, sometimes close to the speed of light.3. An electron emitted at high velocity from a radioactive atom that is undergoing spontaneous disintegration.
Beta particles do not exist in the nucleus but are created during disintegration, or beta decay, when a neutron converts to a proton to emit an electron.
2. A stream of electrons projected by radioactive substances.
They are identical with cathode rays, possess great penetrative power, and are easily deflected by an electric or magnetic field in a direction opposite to that of the alpha rays.
2. In electroencephalography, a rapid rhythm usually of low voltage, which can be recorded in the motor areas of the brain and sometimes in the frontal regions; especially, during states of stress or anxiety or after the administration of certain drugs such as barbiturates.
3. The second most common waveform occurring in electroencephalograms of the adult brain, characteristically having a frequency from 13 to 30 cycles per second.
It is associated with an alert waking state but can also occur as a sign of anxiety or apprehension.
These agents are used in treating hypertension, angina, certain cardiac arrhythmias, and postmyocardial infarction.
They may also be helpful in preventing migraine and in treating stage fright and benign essential tremor.
A hormone, secreted by the adrenal gland and similar to epinephrine, that is the principal neurotransmitter of sympathetic nerve endings supplying the major organs and skin.
It increases blood pressure and rate and depth of breathing, raises the level of blood sugar, and decreases the activity of the intestines.
2. Medications that reduce heart rate and force contraction as well as dilate blood vessels, lowering blood pressure.
They are prescribed for coronary artery disease; including angina, irregular heart rhythms, and a history of heart attack, as well as, to prevent migraine headaches.
2. An accelerator in which electrons are accelerated to high energies by an electric field produced by a changing magnetic field.
3. An electromagnetic apparatus for liberating electrons and accelerating them in a quarter-cycle alternating field to the required velocity for discharge against a chosen target.
2. Designating either of two atoms, one of which has been formed by the ejection of a beta particle from the nucleus, with an increase of 1 in he nuclear charge.