A clinical trial is defined by NIH as a research study in which one or more human subjects are prospectively assigned to one or more interventions (which may include placebo or other control) to ...
In 2021, the Meadowcroft Rockshelter in Pennsylvania was identified as the oldest human occupational site in North America, dated to at least 16,000 radiocarbon years old, or 19,000 calendar years old ...
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