Smallpox may have been the greatest infectious killer in history. Outbreaks occurred in Ancient Egypt, and by the 16th century it routinely killed 10–15 per cent of every generation. As late as the 1960s, it killed an estimated 2 million people per year, and perhaps as many as 500 million over the course of the 20th century. In 1956 the World Health Organization launched a campaign to eliminate the disease. By 1980 smallpox was declared eradicated
Nikolai C.je citiraoпре 5 година
she worked diligently, fine-tuned her instruments, and, with the help of Gosling, captured a series of amazing photos of DNA, including one nicknamed Photo 51, which has been described as the most important photograph ever taken
Nikolai C.je citiraoпре 5 година
The process of a disease jumping from one species to another, particularly from animals to humans, is known as zoonosis.
Nikolai C.je citiraoпре 5 година
The Long March and the Japanese invasion ultimately gave the communists the advantage and control of China, making Mao and the Chinese communists models for radicals elsewhere and upending the world’s power balance
Nikolai C.je citiraoпре 5 година
The Battle of Dien Bien Phu in 1954, in which communist forces overwhelmed a key French garrison, ultimately brought an end to French colonialism in Vietnam
Nikolai C.je citiraoпре 5 година
Transistors work by controlling the amount of electrical current. Operating as an amplifier, a transistor takes a small current and produces a larger one.
Nikolai C.je citiraoпре 5 година
The first atomic bombs (A-Bombs) worked through nuclear fission, or breaking apart the nucleus of atoms. Hydrogen bombs (H-Bombs) add on a process of nuclear fusion, forcing two or more nuclei to fuse together. H-bombs are thermonuclear weapons, which use the heat created by a nuclear fission bomb to ignite nuclear fusion, giving the bombs even more destructive power. Virtually all modern nuclear weapons use thermonuclear technology.
Nikolai C.je citiraoпре 5 година
This observation, together with his earlier (1915) theory that distance and time are not absolute (but are affected by motion and gravity)
Nikolai C.je citiraoпре 5 година
Einstein predicted that light rays from distant stars were deflected by the gravity pull of the Sun.
☁️ ursula ☁️je citiraoпре 7 година
An early African member of the Liberal Party, Lumumba travelled to Belgium and returned convinced that Africans could aspire to independence. He was arrested and imprisoned shortly upon his return. In the late 1950s, Lumumba intensified his political engagement and repeatedly found himself in leadership roles. Helping to launch the anti-colonial Mouvement national congolais (MNC) in 1958, he became the group’s president.