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hemp

(Encyclopedia)hemp, common name for a tall annual herb (Cannabis sativa) of the family Cannabinaceae, native to Asia but now widespread because of its formerly large-scale cultivation for the bast fiber (also calle...

United Nations Conference on Environment and Development

(Encyclopedia)United Nations Conference on Environment and Development (UNCED) or Earth Summit, an 11-day meeting held in June, 1992, in Rio de Janeiro, Brazil, to discuss the global conflict between economic devel...

anemia

(Encyclopedia)anemia ənēˈmēə [key], condition in which the concentration of hemoglobin in the circulating blood is below normal. Such a condition is caused by a deficient number of erythrocytes (red blood cell...

immunology

(Encyclopedia)immunology, branch of medicine that studies the response of organisms to foreign substances, e.g., viruses, bacteria, and bacterial toxins (see immunity). Immunologists study the tissues and organs of...

horseshoe crab

(Encyclopedia)horseshoe crab, large, primitive marine arthropod of the family Limulidae, related to the spider and scorpion and sometimes called a king crab (a name also used for the largest of the edible true crab...

Alzheimer's disease

(Encyclopedia)Alzheimer's disease ălsˈhīˌmərz, ôls– [key], degenerative disease of nerve cells in the cerebral cortex that leads to atrophy of the brain and senile dementia and, ultimately, death. The disea...

bee

(Encyclopedia)bee, name for flying insects of the superfamily Apoidea, in the same order as the ants and the wasps. Bees are characterized by their enlarged hind feet, typically equipped with pollen baskets of stif...

Moerner, W. E.

(Encyclopedia)Moerner, W. E. (William Esco Moerner), 1953–, American physical chemist, b. Pleasanton, Calif., Ph.D. Cornell, 1982. Moerner worked at the IBM Almaden Research Center from 1981 to 1995 and at the Un...

aschelminths

(Encyclopedia)CE5 Internal anatomy of a female rotifer, representative of the phylum Aschelminthes aschelminths ăsk-hĕlmĭnˈthz [key], large assemblage of loosely related, wormlike organisms of extremely var...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...