如果您问什么生物结构最不像自然进化的，那应该就是细菌的鞭毛马达。大部分细菌都可以在需要的时候长出鞭毛，然后通过旋转鞭毛来移动自己，以便寻找食物和躲避危险。但是鞭毛的基座有一个生物界最不寻常的结构，正是它驱动了鞭毛旋转。因为这个纳米级基体像机械马达一样工作，因此被称为鞭毛马达。
Abstract:Blazars are active galactic nuclei with relativistic jets whose non-thermal radiation is extremely variable on various timescales. This variability seems mostly random， although some quasi-periodic oscillations ， implying systematic processes， have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare in AGN and their nature is highly debated， explained by emitting plasma moving helically inside the jet， plasma instabilities or orbital motion in an accretion disc. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae during a dramatic outburst in 2020. BL Lac， the prototype of a subclass of blazars， is powered by a 1.7 × 108 MSun black hole in an elliptical galaxy . Our observations show QPOs of optical flux and linear polarization， and γ-ray flux， with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities near a recollimation shock about 5 parsecs from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array image.
加州大学洛杉矶分校实验室的一次意外，揭开了无机界与生命起源的神秘纽带。博士生黄依琳在锗晶片上蒸镀10nm铬+4nm金双层金属膜时，因样本意外暴露湿气，竟催化出数百个精密螺旋图案——从阿基米德螺线到莲花状分形，最小单元直径仅260微米，堪比人类卵细胞大小。
纳米技术革命发轫纳米机器人一.前言如果说人类智慧有一个区域的话，那么，科学向更小的或是更大的长度单位不断扩展，就标志着人类视野的不断开阔。 在工业革命以前，大部分人类生产、科研不需要用到毫米，“毛估估”的做法说明了我们对这个世界认知的粗浅。
