（三）在铁路、城市轨道交通线路、桥梁、隧道、涵洞处挖掘坑穴、采石取沙的；
Фото: Валерий Шарифулин / ТАСС
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They repeatedly ask their superiors for permission to use live ammunition, after batons, water cannons and rubber bullets fail to disperse the crowd.
It’s also worth noting that even if alternatives superior to agar were found, scientists are reluctant to abandon established protocols (even when microbiologists do use other jellies, they often still add agar to the mix, for example, to increase the gel strength of the solid media). As agar has been the standard gelling agent in microbiology for around 150 years, an enormous infrastructure of standardized methods, reference values, and quality control procedures has emerged around its specific properties. Switching to a different medium (even a superior one) means results may not be directly comparable to decades of published literature or to other laboratories’ findings.