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次生代谢产物异黄酮是一类主要在豆科植物中合成的多酚类物质。异黄酮不仅利于豆科植物应答生物和非生物胁迫、诱导根瘤形成等,而且对人体具有重要的保健和药用价值,比如预防和治疗癌症、心脑血管疾病和骨质疏松等。大豆是工业化生产异黄酮的重要来源,主要含有12种异黄酮物质及其衍生物。根据其化学结构的差异,可将其分为游离型苷元(aglycone)和结合型糖苷(glycoside)两大类,其中结合型糖苷占异黄酮总量...
At the time of the Big Bang, 13.8 billion years ago, every particle of matter is thought to have been produced together with an antimatter equivalent of opposite electrical charge. But in the present-...
Nearly 20 years ago, scientists developed ways to stimulate or silence neurons by shining light on them. This technique, known as optogenetics, allows researchers to discover the functions of specific...
褐飞虱是水稻生产中最严重的害虫。褐飞虱通过针状口器刺入水稻叶鞘组织吸食韧皮部汁液,造成水稻严重减产甚至绝收。种植抗性品种是综合防控褐飞虱的基础。然而植物抗病虫性通常受光照、温度和湿度等环境因素的影响,在一定程度上制约了抗性基因的有效利用。如采用密植的栽培方式是当前许多作物增加单位面积产量的重要途径,但是密植通常会导致冠层以下的植株部分光照不足而产生庇荫反应,易滋生各类病虫害,虽然这种现象普遍存在,...
The source localization and distance inference of gravitational waves (GWs) are two crucial factors for GW standard sirens as precise probes of cosmology, astrophysics, and fundamental physics. In thi...
What a long, strange trip it’s been for psychedelic drugs. From their use in ancient indigenous ceremonies, to their often-caricatured association with the 1960s counterculture, to their recent reemer...
A team led by a Brown biologist discovered that the same specialized brain area that helps songbirds learn their songs also exists in woodpeckers, suggesting that the communicative drumming evolved in...
Cramming multiple pairs of shoes into a vacation suitcase, twisting and flipping them into different arrangements to fit every pair needed, is a familiar optimization problem faced by harried traveler...
Through his close relationship with the woods of Walden Pond in Concord, Massachusetts, Henry David Thoreau observed the ebb and flow of the natural world first-hand. Prolific in his practice of colle...
Controlling light at the nanometer scale is essential for high-resolution imaging, biological sensors, and cell phones. However, having precise, efficient control over light remains a major challenge ...
It looks like fireflies flickering in the darkness. Slowly, more and more amass, lighting up the screen in large chunks and clusters.
Most organisms have proteins that react to light. Even creatures that don’t have eyes or other visual organs use these proteins to regulate many cellular processes, such as transcription, translation,...
近日,北京航空航天大学的研究人员提出了一种新的漫射光学成像方法,利用结构光对吸收和散射效应进行解耦合,使用同时具有数百万调控单元和数十微秒调控速度的数字微镜阵列作为结构光调控器件,通过半色调(halftone)编码方法和散射介质的低通特性,打破了数字微镜阵列连续调(continuous-tone)编码造成的调控速度瓶颈,相比state-of-the-art,将成像速度提高了近100倍。该方法可以对...
Cut off the head of a three-banded panther worm, and it will grow another — mouth, brain, and all. Cut off its tail, and the same thing happens. Cut it in three pieces, and within eight weeks there’ll...

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