In several countries, fire safety officials encourage citizens to use the two annual clock shifts as reminders to replace batteries in smoke and carbon monoxide detectors, particularly in autumn, just before the heating and candle season causes an increase in home fires. Similar twice-yearly tasks include reviewing and practicing fire escape and family disaster plans, inspecting vehicle lights, checking storage areas for hazardous materials, reprogramming thermostats, and seasonal vaccinations. Locations without DST can instead use the first days of spring and autumn as reminders.
In addition to smoke detectors, what do fire safety officials suggest people replace batteries in when they set their clocks twice a year?
carbon monoxide detectors

In 1827, Hungarian physicist Anyos Jedlik started experimenting with electromagnetic coils. After Jedlik solved the technical problems of the continuous rotation with the invention of the commutator, he called his early devices "electromagnetic self-rotors". Although they were used only for instructional purposes, in 1828 Jedlik demonstrated the first device to contain the three main components of practical DC motors: the stator, rotor and commutator. The device employed no permanent magnets, as the magnetic fields of both the stationary and revolving components were produced solely by the currents flowing through their windings.
What discovery solved the problem of continuous rotation?
commutator

The process of desegregation at Washington University began in 1947 with the School of Medicine and the School of Social Work. During the mid and late 1940s, the University was the target of critical editorials in the local African American press, letter-writing campaigns by churches and the local Urban League, and legal briefs by the NAACP intended to strip its tax-exempt status. In spring 1949, a Washington University student group, the Student Committee for the Admission of Negroes (SCAN), began campaigning for full racial integration. In May 1952, the Board of Trustees passed a resolution desegregating the school's undergraduate divisions.
What student group campaigned for full integration at Washington University in 1949?
the Student Committee for the Admission of Negroes (SCAN)