2019-05-24

封面图展示的是有着9 900万年历史的一只蝎子，它是成千上万块标本中的一块，被完美地保存在琥珀中，为我们提供了前所未有的白垩纪森林生活的视角。但在饱受战争破坏的缅甸，琥珀通常在没有科学监督的情况下被挖掘出来，走私到中国，然后在商业市场上出售。中国科学家们正在研究这个属于私人收藏品的标本。

This 99-million-year-old scorpion, perfectly preserved in amber, is one of thousands of specimens offering an unprecedented view of the life of a Cretaceous forest. But the amber is typically excavated without scientific oversight in war-torn Myanmar, smuggled into China, and then sold in a commercial market. Chinese scientists are studying this specimen, which belongs to a private collection.

2019-05-31

在2014年10月22日观测到的紫外光中的太阳，接近11年太阳活动周期中的太阳活动高峰期。在这张来自美国国家航空航天局（NASA）太阳动力学天文台的图片中，20多年来观测到的最大的太阳黑子喷发到了太空中（中间白色部分）。视图已经被旋转了，南方位于图像顶部。太阳活动高峰期是指许多太阳黑子和强烈的太阳风暴出现的时期，这时危险的带电粒子会被投掷向地球。

The Sun, as seen in ultraviolet light on 22 October 2014, near solar maximum in the 11-year solar cycle. In this image from NASA's Solar Dynamics Observatory, the largest sunspot observed in more than two decades erupts into space (white, center). The view has been rotated; south is at the top. Solar maximum is a time of many sunspots and strong solar storms, which can hurl dangerous charged particles at Earth.

2019-06-07

封面图展示的是通过三维共聚焦显微镜重建的人体气道类器官样本（蓝色部分为DNA；红色部分为CD24）。在培养物和平台上生成的类器官为研究正常器官发育与病变提供了极好的模型系统。本期特刊着重介绍了当前类器官研究的几个特点。

Reconstruction of a human airway organoid by 3D confocal microscopy (DNA, blue; CD24, red). Organoids generated in culture and on platforms provide excellent model systems for the study of normal organ development and disease. This special issue highlights several features of current organoid research.

2019-06-14

封面上展示的是小卫星达佛涅斯（半径为4千米）在土星A环的基勒环缝内绕轨道运行，这张照片是由卡西尼号太空飞船拍摄的。潮汐的力量将附近的环粒子激发成波状模式。为了进行图示说明，在图像的顶部和底部的数据缺口已经根据测量过的环特性人为地填补好了。

The small moon Daphnis (radius 4 km) orbits within the Keeler gap in Saturn's A ring, seen in this image taken by the Cassini spacecraft. Tidal forces excite the nearby ring particles into a wavelike pattern. Gaps in the data at the top and bottom of the image have been artificially filled for illustrative purposes using measured properties of the rings.