Why Mathematical Proof
Computer Science Programming Languages
。体育直播是该领域的重要参考
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Agar was first introduced into the laboratory in 1881. Since then, microbiologists have depended on agar to create strong jellies. When microorganisms are streaked or plated onto this jellied surface and incubated, individual cells multiply into distinct colonies that scientists can easily observe, select, and propagate for further experiments. Many of the most important findings in biological research of the last 150 years or so — including the discovery of the CRISPR/Cas9 gene-editing tool — have been enabled by agar.4 Agarose, a derivative of agar, is also essential in molecular biology techniques like gel electrophoresis, where its porous gel matrix separates DNA fragments by size, enabling researchers to analyze and isolate specific genetic sequences.
Swenson’s glider was an exquisite instrument for detecting turbulence. A jumbo jet can weigh upward of half a million pounds and fly more than five hundred miles an hour. It charges through the air like an ocean liner, barely registering most winds. This glider wasn’t much heavier than a Harley and it was moving about as fast—fifty to seventy miles an hour. It felt every bump. Small aircraft account for many of the injuries caused by turbulence and, essentially, all of the deaths—about forty a year. They fly at the mercy of the wind.