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Overview

A20

A cytoplasmic zinc finger protein (790 aa) that inhibits NFκB activity and TNF-mediated programmed cell death. The expression of the A20 mRNA is upregulated by TNFα. It is a dual function ...

Matter

Matter  

Magic Universe: A Grand Tour of Modern Science

...from frozen energy— see Energy and mass . The raw materials of the Universe, initially hydrogen and helium, seem to have been created in a sudden event— see Big Bang . During the process, matter may have existed briefly in a peculiar form— see Quark soup . A mystery is why equal quantities of antimatter were not created, which would have annihilated all ordinary matter— see Antimatter . In the Standard Model of late 20th-century particle physics, the basic constituents of atomic nuclei are quarks of various kinds, associated in protons and neutrons— see ...

computer

computer   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
518 words

...a personal computer kit called the Altair. Bill Gates , a 20-year-old Harvard student, and his high-school friend Paul Allen , 22, wrote a software program for it. Gates dropped out of Harvard to develop the Microsoft Corporation, the software firm he and Allen founded in 1975 for the Altair venture. In 1976 , Steve Wozniak , 25, and Steve Jobs , 20, began marketing a personal computer, the Apple, the first model of which they built in the home garage of Jobs's parents. In 1977 , Jobs and Wozniak brought out the Apple II, which sported a keyboard, a...

space station

space station   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
743 words

...race has begun the ultimate journey to the stars. W. David Compton and Charles D. Benson , Living and Working in Space: A History of Skylab (1983). Tim Beardsley , The International Space Station: A Work in Progress , Scientific American (May 1999): 20–23. Leonard David , Special Report: International Space Station , Aerospace America (July 1999): S1–S15. Kirsten Roundtree , The International Space Station a Year Later , Launchspace (October/November 1999): 35–39. http://spaceflight.nasa.gov/station/index.html. Victor P. Budura,...

centrifuge and ultracentrifuge

centrifuge and ultracentrifuge   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
563 words

.... Around the turn of the twentieth century, amphibian and fish eggs were centrifuged to observe their development under conditions of changed gravity. Today, “ultracentrifuge” signifies all centrifuges that spin faster than 20,000 rpm. The first machine so called, developed by the Swedish colloid chemist The Svedberg in the 1920s, was a device used solely to determine the size of colloid particles. Svedberg and his collaborators developed two different methods: velocity sedimentation (the observation of the sedimentation process in time) and equilibrium...

Bernal's ladder

Bernal's ladder   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
608 words

... flourished in London in the mid-20th century as a crystallographer, military scientist and left-wing social critic. He described the sequence of responses from fellow scientists, as an idea gradually ascends from rejection to acceptance: 1. It can't be right. 2. It might be right but it's not important. 3. It might be important but it's not original. 4. It's what I always thought myself. Bernal's ladder is in continual use. Albeit subjectively, one can give examples of the status, at the start of the 21st century, of a few of the discoveries and ideas...

Bunsen burner

Bunsen burner   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
285 words

...and was perfectly suited to laboratory operations. The present form of the Bunsen burner, familiar to every science student today, has scarcely changed from the original of 1855 . G. Lockemann , The Centenary of the Bunsen Burner , Journal of Chemical Education 33 (1956): 20–21. A. J....

Relativity

Relativity   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
326 words

...could have predicted the expansion of the Universe, but he fumbled it twice. First he added a cosmological constant to prevent the expansion implied by his theory, and then he decided that was a mistake. In the outcome, his cosmological constant reappeared at the end of the 20th century when astronomers found that the cosmic expansion is accelerating, driven by Dark energy . Special relativity seems unassailable, but doubts arise about general relativity because of a mismatch to quantum theory. These are discussed in Gravity and Superstrings...

Evolution

Evolution   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
3,787 words

...between groups within a population become so great that they stop breeding with each other. His successors made progress during the 20th century in this respect, but only in rather simple situations where, for example, small groups of individuals, separated by distance or barriers from their relatives, evolve in a distinctive way. Great leaps of evolution, like those that turned a fish into an air-breather, remained unaccountable. Even Hamilton's stabs at the problem were, for him, strangely tentative. If natural selection was a slow process, gene by...

Extinctions

Extinctions  

Magic Universe: A Grand Tour of Modern Science

... James Thurber , who was then a teenager in Ohio, ‘except that I was left with curious twitching of my left ear after sundown and a tendency to break into a dog-trot at the striking of a match or the flashing of a lantern.’ The false alarms did not invalidate the proposition, self-evident to astronomers, that cosmic traffic accidents were inevitable and one should look for the evidence of past events in the history of the Earth. It was a textbook case of scientists in different fields having incompatible mind-sets. By the mid-20th century, astronomers were...

Discovery

Discovery   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
3,519 words

...Libby , whilst a theoretical physicist, Erwin Schrödinger , inspired many by first specifying the idea of a genetic code. ‘There you are,’ said Graham Smith , showing a photograph of himself and Martin Ryle working on a primitive radio telescope in a field near Cambridge in 1948 . ‘Two future Astronomers Royal, and neither of us knew what right ascension meant.’ Intruding into astronomy without a by-your-leave, they were radio physicists on the brink of pinpointing several dozen of the first known radio sources in the sky. Within 20 years the incomers...

slogans from science

slogans from science   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
883 words

...18 The action of atmospheric gases to prevent solar energy, degraded into heat, from escaping from the earth, in the manner of the glass in a greenhouse. 19 A rift in the barrier that helps prevent harmful ultraviolet rays from reaching the earth. 20 The notion that the “development of the embryo is an abstract of the history of the genus,” thus formulated by Ernst Haeckel in 1874 . 21 “Nothing comes from nothing,” a scholastic slogan. 22 “Everything comes from the egg.” 23 The DNA model proposed by James Watson and Francis Crick ( See Molecular...

aberration, stellar

aberration, stellar   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
484 words

...of the incoming light from a star, the observed direction of the star deviates from its true direction. This deviation, known as aberration, depends on the velocity of the observer on the earth and on the velocity of light. The maximum deviation owing to the earth's moving around its orbit is 20.5 seconds of arc. The earth's spin produces an additional much smaller diurnal aberration. James Bradley , England's third Astronomer Royal, discovered stellar aberration serendipitously. He was looking for evidence of stellar parallax, a concept at the heart of the...

mass spectrograph

mass spectrograph   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
630 words

...m ), and hence for studying their mass and chemical nature. In 1912 Joseph John Thomson and his assistant Francis Aston , analyzing positive rays (ions that stream through a hole in the cathode of a gas-discharge tube), discovered an ion closely associated with that of neon, atomic mass 20, but corresponding to mass 22. For several years identification of this ion as a compound, a new element, or an isotope of neon remained uncertain, but from 1913 Frederick Soddy actively promoted it as evidence of isotopes in nonradioactive substances. The subsequent...

Sun's interior

Sun's interior  

Magic Universe: A Grand Tour of Modern Science

...rises, falls and rises again in a roughly 11-year cycle is linked with big changes in the Sun's magnetic field. It swaps its north and south magnetic poles around at each sunspot maximum, when general magnetic activity in the stormy atmosphere also peaks. Half a century after Hale's pioneering discovery about the Sun's magnetic fields, and 20 years after his death in 1938 , one of his old solar telescopes on Mount Wilson opened a window into the interior of our mother star. At first it was for only a glimpse. But that inspired a new science, which by the end of...

Ocean currents

Ocean currents  

Magic Universe: A Grand Tour of Modern Science

...still remains a mystery.’ Called the mesoscale circulation, the eddies possess in total 20 times more energy of motion than the large-scale currents that traverse the oceans. They are often associated with jets, watery equivalents of jet streams in the air, and they play a part in maintaining the currents. Locally, the eddies can add to or subtract from the mean speed of a current, or totally alter the direction of flow. So how did the research ships, diligently sampling all the ocean currents, come to miss them? Walter Munk of UC San Diego had a sarcastic...

universe, age and size of the

universe, age and size of the   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
728 words

...the curious anomaly of a calculated value of the age of the universe that was smaller than radiometric measurements of the age of the earth. The work of Walter Baade in the 1940s and Allan Sandage in the 1950s resulted in substantial revisions in the accepted value of Hubble's Constant, and by the 1960s astronomers agreed that the universe was between 10 and 20×10 9 years old, with a corresponding size of the order of 10 10 light-years. Also by the 1960s, the success of the “Big Bang” Hypothesis had provided astronomers with a causal physical model of...

dialectical materialism

dialectical materialism   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
498 words

...ignored it. See also Causality ; Vavilov, Nikolai Ivanovich , and Sergei Ivanovich Vavilov . Loren R. Graham , Science and Philosophy in the Soviet Union (1972). Helena Sheehan , Marxism and the Philosophy of Science: A Critical History (1993). Ernst Mayr , Roots of Dialectical Materialism, in Na Perelome: Sovetskaia Biologiaa v 20–30kh Godakh , ed. E. I. Kolchinskii (1997): 12–17. Loren R....

longitude

longitude   Reference library

The Oxford Companion to the History of Modern Science

Reference type:
Subject Reference
Subject:
Science and technology, History of Science
Length:
599 words

...to the longitude problem—the £ 20,000 prize established in Britain in 1714 to be administered by a Board of Longitude—resulted in enormous interest in the problem in the eighteenth century, and eventually the completion of both the chronometer and lunar-distance methods, seen as rivals throughout their development but used in complementary ways in the navigational practices of the nineteenth century. Both Johann Tobias Meyer (posthumously), for lunar work, and John Harrison , for a chronometer, received part rewards from the Board, Harrison's being...

Immortality

Immortality   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
2,299 words

...train Research on ageing in the mid-20th century was confounded by a misleading report by a French scientist, Alexis Carrel . In 1929 he declared that ordinary animal cells grown in a lab culture would thrive indefinitely. By 1946 he was claiming to have kept cells from a chicken's heart alive for 34 years. When nobody else managed to make normal cells survive like that, sloppy work by the scientist, or by some unfortunate lab assistant, took the blame. Carrel was a Nobel Prizewinner, so you had to be a brave researcher to contradict him. At the...

Climate change

Climate change   Reference library

Magic Universe: A Grand Tour of Modern Science

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, History of Science
Length:
3,591 words

...climate intervened. In the late 1970s the global temperature trend reversed and a rewarming began. A decade after that, Bolin was chairman of an Intergovernmental Panel on Climate Change. In 1990 its report Climate Change blamed the moderate warming of the 20th century on man-made gases, and predicted a much greater warming of 3°C in the 21st century, accompanied by rising sea-levels. This scenario prompted the world's leaders to sign, just two years later, a climate convention promising to curb emissions of greenhouse gases. Thenceforward, someone...

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