这一代的屏幕显示素质拉完了，X 都不买。
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Some smoke alarms have been designed to be ultra-sensitive. Aspirating devices, for example, constantly suck in air in order to detect even small quantities of smoke in a room. They are often used in commercial settings, including server rooms packed with expensive computer tech.
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.