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Lotze, Rudolf Hermann

(Encyclopedia)Lotze, Rudolf Hermann ro͞oˈdôlf hĕrˈmän lōˈtsə [key], 1817–81, German philosopher and psychologist. After studying medicine and philosophy at Leipzig, he was lecturer in both departments an...

naturalism, in philosophy

(Encyclopedia)naturalism, in philosophy, a position that attempts to explain all phenomena and account for all values by means of strictly natural (as opposed to supernatural) categories. The particular meaning of ...

parathyroid hormone

(Encyclopedia)parathyroid hormone or parathormone, a hormone secreted by the parathyroid glands that regulates the metabolism of calcium and phosphate in the body. It has been purified extensively and appears to be...

organic farming

(Encyclopedia)organic farming, the practice of growing plants—especially for fruits and vegetables, but for ornamentals as well—without the use of synthetic pesticides, herbicides, and fertilizers, or of raisin...

warfare

(Encyclopedia)warfare, violent conflict between armed enemies. In modern times warfare has usually been conducted by the armed forces (e.g., army, navy, and air force) of a nation or other politically organized gro...

adolescence

(Encyclopedia)adolescence, time of life from onset of puberty to full adulthood. The exact period of adolescence, which varies from person to person, falls approximately between the ages 12 and 20 and encompasses b...

bioethics

(Encyclopedia)bioethics, in philosophy, a branch of ethics concerned with issues surrounding health care and the biological sciences. These issues include the morality of abortion, euthanasia, in vitro fertilizatio...

anthrax

(Encyclopedia)anthrax ănˈthrăks [key], acute infectious disease of animals that can be secondarily transmitted to humans. It is caused by a bacterium (Bacillus anthracis) that primarily affects sheep, horses, ho...

enzyme

(Encyclopedia)enzyme, biological catalyst. The term enzyme comes from zymosis, the Greek word for fermentation, a process accomplished by yeast cells and long known to the brewing industry, which occupied the atten...

space medicine

(Encyclopedia)space medicine, study of the medical and biological effects of space travel on living organisms. The principal aim is to discover how well and for how long humans can withstand the extreme conditions ...