圖像加註文字，貿易與關稅將成為特朗普（川普）與習近平4月會晤的議題。美國白宮週六表示，總統特朗普將於3月31日至4月2日訪問中國，但中方尚未確認特朗普訪華的消息。Article InformationAuthor, 安東尼‧澤克爾（Anthony Zurcher）
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.
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takes a bit more of a hands-on approach to getting your account fully set up,