2017-06-23
就像封面圖上“脊椎動物西部基金會”的收藏品那樣,鳥類產(chǎn)的卵在顏色、圖案、大小及形狀等方面各有不同。一項由Stoddard等人進(jìn)行的調(diào)查推翻了我們的傳統(tǒng)觀點,掲示出鳥蛋的形狀與其飛行能力有關(guān)。另外,鳥蛋的柔性膜(不是指蛋殼)也許是鳥蛋形狀各異的原因之一。
Birds lay eggs in a diverse array of colors, patterns, sizes, and shapes, as seen in this assortment from the Western Foundation of Vertebrate Zoology collection. An investigation by Stoddard et al. reveals that egg shape is related to flight ability in birds, overturning classic theories. Additionally, the egg s flexible membrane (not the shell) might be responsible for the great variety of egg shapes.
2017-06-30
封面上展不的是一株矮牽?;ǖ慕S表面圖。每天晚上,矮牽?;ɑò甑腻F形表皮細(xì)胞就會釋放出揮發(fā)性的有機(jī)化合物。這種揮發(fā)性的排放,曾經(jīng)被認(rèn)為僅僅是由擴(kuò)散產(chǎn)生的,實際上是在二麟酸腺苷(ATP)結(jié)合盒轉(zhuǎn)運載體蛋白的幫助下進(jìn)行的主動轉(zhuǎn)運。
Adaxial surface of a petunia flower. Each night, volatile organic compounds are released from conically shaped epidermal cells of petunia flower petals. Volatile emission, once thought to be driven solely by diffusion, is dependent on active transport facilitated by A TP—binding cassette transporters.
2017-07-07
封面上的這幅概念插圖描繪的是一個人造神經(jīng)元喚醒了一項正在改變許多科學(xué)領(lǐng)域的技術(shù):人工智能(簡稱“AI”)。人工智能的一種常見形式就是神經(jīng)網(wǎng)絡(luò),作為模擬神經(jīng)元之間的橋梁——“學(xué)習(xí)”改變了對輸入指令的應(yīng)對方式。這樣的系統(tǒng)可以在大量的數(shù)據(jù)組中找到有意義的模式,應(yīng)用范圍從基因組學(xué)到天文學(xué),甚至已經(jīng)開始設(shè)計各種實驗了。
A conceptual illustration of an artificial neuron evokes a technology that is transforming many fields of science : artificial intelligence (AI). One common form of AI is a neural network, which“l(fā)earns” as connections between simulated neurons change in response to inputs. Such systems can find meaningful patterns in vast data sets, ranging from genomics to astronomy, and are even beginning to design experiments.
2017-07-14
封面圖展不的是2016年美國佛羅里達(dá)州邁阿密的一位園丁正在噴灑除蚊子的殺蟲劑。寨卡病毒是通過無處不在的埃及伊蚊傳播的。這種黃病毒已經(jīng)在南美洲引起了大規(guī)模的爆發(fā)性感染,研究表明與新生兒的神經(jīng)系統(tǒng)異常有關(guān)。目前,該病毒已經(jīng)擴(kuò)散到北部地區(qū),并且在美國境內(nèi)也已經(jīng)發(fā)現(xiàn)了感染病例。
A groundskeeper sprays pesticide to control mosquitoes in Miami, Florida, in 2016. Zika virus is spread by the ubiquitous Aedes aegypti mosquito. This flavivirus has caused a huge outbreak of infection across South America, where it has been associated with neurological abnormalities in newborn children. The virus has spread north, and cases of infection have been detected in the United States.endprint