2017-04-28

疫苗是我們對抗眾多傳染性疾病的最佳防御手段，通過接種疫苗挽救了數(shù)百萬生命，并使人們免受痛苦的折磨。但是現(xiàn)如今，在許多發(fā)展中國家，一些父母由于受到關于風險的持續(xù)性不實信息的影響，在決定是否要給自己的孩子接種疫苗的時候猶豫不決。本期中的特別章節(jié)針對接種疫苗有可能產(chǎn)生的真實的、罕見的風險進行了評估，并涉及了如何克服毫無根據(jù)的恐懼等內容。

Vaccines are our best defenses against many infectious diseases， having saved millions of lives and prevented immeasurable suffering. Yet today， in many developed countries，these defenses are fraying as parents， swayed by persistent untruths about the risks， hesitate to vaccinate their children. This special package sizes up the actual， rare risks of vaccines and what is known about how to overcome groundless fears.

2017-05-05

封面上展示的是一張游戲牌——也就是我們在撲克游戲中使用的紙牌，在牌面上以藝術再現(xiàn)的方式展現(xiàn)了一個數(shù)字電路板。對于這種玩家在游戲中擁有非對稱信息的游戲，例如撲克，已經(jīng)被證實對人工智能具有挑戰(zhàn)性。DeepStack人工智能系統(tǒng)采用一種新的方式，將局部搜索技術引入到游戲中。從而使DeepStack成為了在一對一無限注“德州撲克”中擊敗了職業(yè)撲克玩家的計算機程序。

A playing card—as used in the game of poker— with an artistic rendition of a digital circuit board. Games in which players have asymmetric information during play， such as poker， have proven challenging for artificial intelligence. The computer program DeepStack takes a new approach， bringing local search techniques to such games. DeepStack defeated professional players at heads-up no-limit Texas hold'em poker.

2017-05-12

封面上展示的是位于馬達加斯加西部穆隆達瓦附近的猴面包樹（全稱格朗迪迪埃猴面包樹）林中的日落景象。通過高分辨率衛(wèi)星測繪顯示，類似于這樣的旱地森林，其潛在的蒸發(fā)蒸騰量遠遠超過降水量，林地覆蓋范圍比以前的記錄高出40%。

Sunset at the Avenue of the Baobabs （Grandidier's baobab trees Adansonia grandidieri Baill.） near Morondava， western Madagascar. Highr—esolution satellite mapping reveals that the extent of forest cover in drylands such as this， where potential evapotranspiration substantially exceeds precipitation，is globally more than 40% higher than previously reported.

2017-05-19

許多科學家在多個國家學習和工作著，這就是一個人類遷徙沖動驅使下的極端例子。通過開放研究者與貢獻者身份識別碼（ORCID）的數(shù)據(jù)重構，封面圖中描繪了個體科學家在其職業(yè)生涯中所經(jīng)歷的歷程；藍色路徑代表Rimantas Kodzius的軌跡，他可能是在世的遷徙次數(shù)最多的科學家。見本期有關于人口遷徙的特別章節(jié)。

In an extreme example of humans' migratory urge，many scientists study and work in multiple countries. The cover depicts the journeys of individual scientists over the course of their careers， as reconstructed from data in ORCID； the blue path represents the trajectory of Rimantas Kodzius， who may be the most migratory living scientist. See special section on human migration.endprint