منابع مشابه
Lice, Humans, and Microbes
Lice are small, wingless, minor ectoparasites of mammals and birds. More than 540 blood-sucking lice (Phthiraptera: Anoplura) have been described with each host having its own type of louse, suggesting the cospeciation of the lice species with their host. Among these, two lice species from two different genera infest humans: Pediculus humanus and Phthirus pubis (pubic “crab” l...
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Although most of the rare earth metals were discovered in Sweden, the industrialisation started in the Austrian Empire. This was due to the fact that the Swedish chemist Jons Fridrik Bahr (1815–1875) from Uppsala went to Heidelberg in Germany in 1855 to analyse some rare earth minerals by the spectroscope discovered recently by chemistry professor Robert Bunsen (1811– 1899) and his colleague ph...
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In the third century B.C.E., Eratosthenes of Cyrene made a famous measurement of the circumference of the Earth. This was not the first such measurement, but it is the earliest for which significant details are preserved. Cleomedes gives a short account of Eratosthenes' method, his numerical assumptions, and the final result of 250,000 stades. However, many ancient sources attribute to Eratosth...
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ژورنال
عنوان ژورنال: Nature
سال: 2017
ISSN: 0028-0836,1476-4687
DOI: 10.1038/nature24756