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 seedling with weakened cell adhesion is treated with an inhibitor of the growth hormone brassinosteroid. Brassinosteroid inhibition slows epidermal growth, which constrains growth of internal tissue, causing mechanical stresses and opening cracks as epidermal cells are pulled apart. Similar stresses produce internal contortions of carnivorous plant, Utricularia gibba, illustrating how mechanical connectivity between cells coordinates growth between 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 nitrogen wafts over a rat kidney awaiting a groundbreaking preservation method at the University of Minnesota. Scientists there have learned how to cool the organ to -150°C and rewarm it while minimizing freezing damage, enabling it to work after being transplanted. This laboratory and others are harnessing extreme cold to preserve everything from organs to endangered coral to fresh tomatoes.

2023-07-07

封面上展示的是一氟化铪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。

Hafnium monofluoride molecular ions are suspended in a vacuum chamber by oscillating electric fields and probed with multiple laser beams. A measurement of electrons embedded in these trapped molecules has set a new upper limit on how electrons violate time-reversal symmetry. The measurement provides stringent new constraints on many proposed extensions to the Standard Model of particle physics.

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？

There have been huge strides in the development and application of artificial intelligence (AI) to science and society. But will AI eclipse humans, or will we find a way to safely and fairly collaborate, allowing us to reach further?