منابع مشابه
50 Million Announced Forty Years Ago 100 Million Mexicans… Only
1% in 2000. Although the objective was far from being reached (the current rate being close to 2%), in 2000 Mexico had 53 million inhabitants fewer than it would have had if fertility had remained at its 1970 level. The population pyramids of 1930, 1970 and 2000 clearly illustrate this dynamics (Figure 2). In 1930 the population was beginning to recover from the aftereffects of the Revolution a...
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In 2012 it was forty years ago that the discovery of the first X-ray binary Centaurus X-3 became known. That same year it was discovered that apart from the High-Mass X-ray Binaries (HMXBs) there are also Low-Mass X-ray Binaries (LMXBs), and that Cygnus X-1 is most probably a black hole. By 1975 also the new class of Be/X-ray binaries was discovered. After this it took 28 years before ESAs INTE...
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Supernova 1987A in the Large Magellanic Cloud provides a spectacularly detailed view of the aftermath of a core-collapse explosion. The supernova ejecta initially coasted outward at more than 10% of the speed of light, but in 1990 were observed to decelerate rapidly as they began to encounter dense circumstellar material expelled by the progenitor star. The resulting shock has subsequently prod...
متن کامل40 Years Ago
always voice his unhappy or distressing thoughts, and it is often most difficult to recognise the way he is tending, or having recognised it to induce him to seek the help and advice that would save him. And even when his condition has been realised and the man himself persuaded to have treatment, the difficulties in the ^ay of obtaining it for him are often insuperable. Outside of London and a...
متن کاملTwenty Five Years Ago
so rarely met witH that a description of the following case is not without interest. AEuropean, aged 38, was admitted on the 4th February, 1929, with paresis of the left arm and leg. His previous history showed that he contracted syphilis in 1915, for which he was treated with a full course of murcury and galvarsan. In 1919 his Wasserman reaction was still positive and he had a further course j...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1994
ISSN: 0074-1809
DOI: 10.1017/s0074180900107855