beta; B, β +

A type of globulin in blood plasma that in electrically charged solutions exhibits colloidal mobility between that of the alpha and gamma globulins.

1. A high-speed electron or positron, especially one emitted in radioactive decay.
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.

1. A stream of beta particles, especially of electrons.
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.

1. A pattern of electrical waves in the brain of someone who is awake and active.
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.

A structure that occurs in many proteins and consists of two or more parallel adjacent polypeptide chains arranged so that hydrogen bonds can form between the chains.

A type of secondary structure of proteins in which several parallel polypeptide chains are cross-linked by intermolecular hydrogen bonds, resulting in a flexible, strong arrangement.

The level of taxonomic study dealing with the arrangement of species into lower and higher taxa; or groups to which organisms are assigned according to the principles of taxonomy, including species, genus, family, order, class, and phylum.

The final stage in the testing of new computer software before its commercial release, conducted by testers other than its developers.

An organization or company that tests a software or hardware product under actual working conditions and reports the results to the vendor.

1. The second letter of the Greek alphabet, written as β.
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.

A synthetic or natural drug that stimulates beta or sympathetic receptors.

A substance that interferes with the transmission of stimuli through pathways that normally allow sympathetic nervous inhibiting stimuli to be effective.

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 site in autonomic nerve pathways wherein inhibitory responses occur when adrenergic agents; such as, norepinephrine and epinephrine are released.

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.

1. A drug that relieves heart stress by inhibiting the absorption of adrenalin by the heart and blood vessels.
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.

1. A speech defect giving the b sound to other consonants.
2. A disorder of speech in which the consonant b receives excessive emphasis and other consonants may be pronounced as b.