2023-06-23
封面图展示的是一株细胞黏附减弱的拟南芥幼苗在用生长激素油菜素类固醇抑制剂处理后的状态。油菜素内酯抑制剂会减缓表皮生长,这就限制了内部组织的发展,造成机械应力,并在表皮细胞被拉开时张开裂隙。类似的压力会导致肉食性植物丝叶狸藻的内部扭曲,图解说明了细胞之间的机械连接如何协调细胞层之间的生长。
An Arabidopsis seedlingwith weakened cell adhesion istreated with an inhibitor of thegrowth hormone brassinosteroid.Brassinosteroid inhibition slowse p i d e r m a l g r o w t h , w h i c hconstrains growth of internalt i s s u e , c a u s i n g m e c h a n i c a lstresses and opening cracks asepidermal cells are pulled apart.Similar stresses produce internalcontortions of carnivorous plant,Utricularia gibba , illustratinghow mechanical connectivitybetween cells coordinates growthbetween cell layers.
2023-06-30
封面图展示的是来自液氮的蒸气飘过一个小鼠的肾脏,它正在等待接受明尼苏达大学突破性的保存方法。那里的科学家已经掌握了如何将器官冷却到-150℃然后再回温,同时最大限度地减少冷冻损伤,使其在移植后能够正常工作。这个实验室和其他实验室正在利用这种极寒技术保存各种东西,从器官到濒危珊瑚,以及新鲜西红柿等。
Vapor from liquid nitrogenwafts over a rat kidney awaitinga groundbreaking preservationm e t h o d a t t h e U n i v e r s i t y o fMinnesota. Scientists there havelearned how to cool the organ to-150 ° C and rewarm it whilem i n i m i z i n g f r e e z i n g d a m a g e ,enabling it to work after beingtransplanted. This laboratory andothers are harnessing extremecold to preserve everything fromorgans to endangered coral tofresh tomatoes.
2023-07-07
封面上展示的是一氟化鉿分子中的离子通过振荡电场悬浮在真空室中,并用多个激光束进行探测。通过对嵌入这些被捕获分子中的电子测量为电子如何违反时间反转对称性设定了新的上限。该计量为粒子物理标准模型的许多拟议扩展提供了严格的新约束。
H a f n i u m m o n o f l u o r i d emolecular ions are suspended ina vacuum chamber by oscillatinge l e c t r i c f i e l d s a n d p r o b e dwith multiple laser beams. Ameasurement of electrons embeddedin these trapped molecules hasset a new upper limit on howelectrons violate time-reversals y m m e t r y . T h e m e a s u r e m e n tprovides stringent new constraintson many proposed extensions tothe Standard Model of particlephysics.
2023-07-14
人工智能的发展及其在科学与社会中的应用取得了巨大进步,但到底是人工智能会让人类黯然失色,还是我们会找到一种安全、公平的合作方式,让人类社会走得更远呢?
T h e r e h a v e b e e n h u g estrides in the development andapplication of artificial intelligence(AI) to science and society. Butwill AI eclipse humans, or willwe find a way to safely andfairly collaborate, allowing us toreach further?
(陶 陶 编译)