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Vasconcelos, José

(Encyclopedia)Vasconcelos, José hōsāˈ väskōnsāˈlōs [key], 1882–1959, Mexican educator and writer. He headed (1920–24) the National Univ. of Mexico and, as minister of education under Álvaro Obregón, ...

thyroxine

(Encyclopedia)thyroxine thīrŏkˈsēn [key], substance secreted by the thyroid gland. The hormone thyroxine forms by combining the amino acid tyrosine with iodine. Complexed to a protein, it is stored in the folli...

thermometer

(Encyclopedia)thermometer, instrument for measuring temperature. Galileo and Sanctorius devised thermometers consisting essentially of a bulb with a tubular projection, the open end of which was immersed in a liqui...

scopolamine

(Encyclopedia)scopolamine hīˈəsēnˌ, –sĭn [key], alkaloid drug obtained from plants of the nightshade family (Solanaceae), chiefly from henbane, Hyoscyamus niger. Structurally similar to the nerve substance ...

shock absorber

(Encyclopedia)shock absorber, device for reducing the effect of a sudden shock by the dissipation of the shock's energy. On an automobile, springs and shock absorbers are mounted between the wheels and the frame. W...

Philip Neri, Saint

(Encyclopedia)Philip Neri, Saint nāˈrē [key], 1515–95, Italian reformer. His original name was Filippo Romolo de' Neri. From boyhood he was religious, and in 1533 he went to Rome to study. From about 1537 on, ...

cerebellum

(Encyclopedia)cerebellum sĕrˌəbĕlˈəm [key], portion of the brain that coordinates movements of voluntary (skeletal) muscles. It contains about half of the brain's neurons, but these particular nerve cells are...

Abd al-Majid

(Encyclopedia)Abd al-Majid Turk. äbdülˈ mäjēdˈ [key], 1823–61, Ottoman sultan (1839–61), son and successor of Mahmud II to the throne of the Ottoman Empire. The rebellion of Muhammad Ali was checked by th...

Radek, Karl

(Encyclopedia)Radek, Karl kärl räˈdyĭk [key], 1885–1939?, international Communist leader and journalist, b. Lviv (then in Austrian Poland); his original name was Sobelsohn. Radek participated in the 1905 revo...

sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...