今天白天晴转多云，北转南风二三级，最高气温6℃。今起三天以晴到多云天气为主，午间较适宜户外活动，早晚气温低，体感寒冷，请注意防寒保暖；近期天干物燥，需注意补水保湿和用火用电用气安全。新京报记者 王景曦SourcePh" style="display:none"
Ирина Шейк вышла в свет с бриллиантом на зубахСупермодель Ирина Шейк пришла на музыкальный фестиваль с бриллиантом на зубах
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This was not the first time that microbiologists experienced problems with agar. A phenomenon called “The Great Plate Count Anomaly” baffled researchers in the early 20th century when they observed that the number of cells seen under a microscope didn’t match the actual number of colonies growing on an agar plate. Investigating this discrepancy, researchers found agar itself to be the culprit: when nutrient broths are heated with agar during boiling, harmful byproducts (hydroperoxide) can form due to the reaction of agar with phosphate minerals contained in the media. Researchers can avoid this by autoclaving agar separately from the nutrient broth, or by reducing the amount of agar used.
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