（作者单位：北京大学考古文博学院）
Leonardo da Vinci is usually credited with conducting the first systematic study of friction in the late 15th century, a subfield now known as tribology that deals with the dynamics of interacting surfaces in relative motion. Da Vinci's notebooks depict how he pulled rows of blocks using weights and pulleys, an approach that is still used in frictional studies today, as well as examining the friction produced in screw threads, wheels, and axles. The authors of this latest paper used an experimental setup similar to da Vinci's.
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·乌普萨拉大学教授Emily Holmes领导了这项新研究，着手点主要是影响PTSD发病的重要因素之一的“侵入性记忆”展开，提出了采用“Imagery Competing Task Intervention（图像抵触进程干预）”的治疗思路。
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