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  • From Lithium-Ion to Sodium-Ion Batteries: Advantages, Challenges, and Surprises
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Prasant Kumar Nayak, Liangtao Yang, Wolfgang Brehm, Philipp Adelhelm
    更新日期:2017-11-20
  • GOx@ZIF-8(NiPd) Nanoflower: An Artificial Enzyme System for Tandem Catalysis
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Qingqing Wang, Xueping Zhang, Liang Huang, Zhiquan Zhang, Shaojun Dong
    更新日期:2017-11-20
  • A Supramolecular Capsule for Reversible Polysulfide Storage/Delivery in Lithium-Sulfur Batteries
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Jin Xie, Hong-Jie Peng, Jia-Qi Huang, Wen-Tao Xu, Xiang Chen, Qiang Zhang
    更新日期:2017-11-20
  • Gold-Catalyzed Asymmetric Intramolecular Cyclization of N-Allenamides for the Synthesis of Chiral Tetrahydrocarbolines
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Yidong Wang, Peichao Zhang, Xiaoyu Di, Qiang Dai, Zhan-Ming Zhang, Junliang Zhang
    更新日期:2017-11-20
  • Adsorption-Induced Structural Phase Transformation in Nanopores
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Bogdan Kuchta, Ege Dundar, Filip Formalik, Philip L. Llewellyn, Lucyna Firlej
    更新日期:2017-11-20
  • Dendrimers in combination with natural products and analogues as anti-cancer agents
    Chem. Soc. Rev. (IF 38.618) Pub Date : 2017-11-20
    Serge Mignani, João Rodrigues, Helena Tomas, Maria Zablocka, Xiangyang Shi, Anne-Marie Caminade, Jean-Pierre Majoral
    更新日期:2017-11-20
  • The MOF+ Technique: A Significant Synergic Effect Enables High Performance Chromate Removal
    Angew. Chem. Int. Ed. (IF 11.994) Pub Date : 2017-11-20
    Ming Biao Luo, Yang Yang Xiong, Hui Qiong Wu, Xue Feng Feng, Jian Qiang Li, Feng Luo
    更新日期:2017-11-20
  • Chemical synthesis and NMR spectroscopy of long stable isotope labelled RNA
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-20
    J. Kremser, E. Strebitzer, R. Plangger, M. A. Juen, F. Nußbaumer, H. Glasner, K. Breuker, C. Kreutz
    更新日期:2017-11-20
  • Detection of N6-methyladenosine based on the methyl-sensitivity of MazF RNA endonuclease
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-13
    Miki Imanishi, Shogo Tsuji, Akiyo Suda, Shiroh Futaki
    更新日期:2017-11-20
  • Ruthenium-catalyzed olefinic C–H alkenylation of enol-carbamates: highly stereo-selective synthesis of (Z,Z) and (Z,E)-butadienes
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-10
    Tingyan Li, Jian Zhang, Chunbing Yu, Xiunan Lu, Liqing Xu, Guofu Zhong
    更新日期:2017-11-20
  • A surprising substituent effect in corroles on the electrochemical activation of oxygen reduction
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-10
    Naomi Levy, Jennifer S. Shpilman, Hilah C. Honig, Dan T. Major, Lior Elbaz
    更新日期:2017-11-20
  • In situ formed Fe–N doped metal organic framework@carbon nanotubes/graphene hybrids for a rechargeable Zn–air battery
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-10
    Wenxiu Yang, Yelong Zhang, Xiangjian Liu, Lulu Chen, Jianbo Jia
    更新日期:2017-11-20
  • A universal genotyping–microarray constructed by ligating a universal fluorescence-probe with SNP-encoded flaps cleaved from multiplex invasive reactions
    Chem. Commun. (IF 6.319) Pub Date : 2017-11-10
    Zhiyao Chen, Liyan Miao, Yunlong Liu, Tianhui Dong, Xueping Ma, Xiaoxiang Guan, Guohua Zhou, Bingjie Zou
    更新日期:2017-11-20
  • Beyond plastic waste
    Science (IF 37.205) Pub Date : 2017-11-17
    Ellen MacArthur

    With more than 8 million tons of plastic entering the ocean each year, humanity must urgently rethink the way we make and use plastics, so that they do not become waste in the first place.

    更新日期:2017-11-19
  • News at a glance
    Science (IF 37.205) Pub Date : 2017-11-17
    American Association for the Advancement of Science

    In science news around the world, the Global Carbon Project predicts a 2% rise in carbon emissions this year, an obscure tick-borne malady called Kyasanur Forest disease spreads quickly through India, Republican lawmak­ers in the U.S. Senate are reviving a decadeslong push to open parts of Alaska’s Arctic National Wildlife Refuge to oil and gas drilling, and the Silicon Valley startup Planet Labs announces that its fleet of shoebox-sized space satellites now image Earth’s entire landmass every day. Also, President Donald Trump nominates Alex Azar, an attorney and former pharmaceutical executive, to head the U.S. Department of Health and Human Services, and Bill Gates announces a $100 mil­lion personal investment in Alzheimer’s disease research.

    更新日期:2017-11-19
  • ‘Biased’ opioids could yield safer pain relief
    Science (IF 37.205) Pub Date : 2017-11-17
    Meredith Wadman

    Nearly all of the roughly 64,000 Americans who died from opioid overdoses in 2016 succumbed because their breathing shut down, triggered by the effects of the drugs on important receptors in the brain stem. When they are activated, μ-opioid receptors potently relieve pain. They also control respiration. Now, for the first time, a drug that in binding these receptors causes powerful pain relief with less respiratory suppression is being evaluated for marketing approval by the Food and Drug Administration. Biotech company Trevana’s drug, oliceridine, acts as a μ-opioid receptor to activate a pain-relieving signaling pathway with less triggering of a separate path that leads to depressed breathing. Oliceridine is the first so-called “biased opioid” to emerge from human clinical trials. There will certainly be more: In a paper published inCellthis week, scientists at the Scripps Research Institute in Jupiter, Florida, have rigorously demonstrated for the first time in mice that the more biased a compound is toward activating the pain-relieving pathway, the less it suppresses breathing.

    更新日期:2017-11-19
  • ‘David and Goliath’ weather eyes set for launch
    Science (IF 37.205) Pub Date : 2017-11-17
    Eric Hand

    The polar weather satellite system will soon be safer. After years of rising costs and delays, the $1.6 billion Joint Polar Satellite System-1 (JPSS-1) was set to rocket into orbit this week. If successful, the launch will still fears that a failure of the JPSS-1’s aging predecessor would cripple the armada of polar satellites that provide 85% of the input data for weather forecast models. Hitchhiking on board the same rocket that is carrying the 4-meter-tall JPSS-1 is a strikingly smaller and cheaper probe that is a harbinger of a yet more resilient weather satellite system. The $3 million Microwave Radiometer Technology Acceleration—classed as a CubeSat because its components are stuffed into a stack of three 10-centimeter cubes—carries a cloud-penetrating microwave sensor that rivals one on the much bigger and costlier JPSS-1.

    更新日期:2017-11-19
  • Livestock drove ancient Old World inequality
    Science (IF 37.205) Pub Date : 2017-11-17
    Lizzie Wade

    Economic inequality has deep roots. A new study concludes that its ancient hotbed was the Old World: Societies there tended to be less equal than those in the New World, likely because of the use of draft animals. Researchers collected data on house size distribution from 62 archaeological sites in North America and Eurasia dating from before 8000 B.C.E. to about 1750 C.E. From there, they calculated each site’s Gini coefficient, a standard measure of inequality ranging from zero (perfect equality) to one (a single person has all the wealth). Inequality tended to gradually increase as societies transitioned from hunting and gathering to farming, supporting long-held hypotheses about how agriculture intensified social hierarchies. About 2500 years after the first appearance of domesticated plants in each region, average inequality in both the Old World and the New World hovered around a Gini coefficient of about 0.35. This figure stayed more or less steady in North America and Mesoamerica. But in the Middle East, China, Europe, and Egypt, where people had oxen to plow more land and horses to travel long distances, inequality kept climbing, topping out at an average Gini coefficient of about 0.6 about 6000 years after the start of agriculture. Still, those numbers are far below the wealth inequality seen today in the United States, which has a Gini coefficient of 0.8.

    更新日期:2017-11-19
  • After failed rescue effort, rare porpoise in extreme peril
    Science (IF 37.205) Pub Date : 2017-11-17
    Elizabeth Pennisi

    Last month, the Mexican government and an international team launched a last-resort plan to save the vaquita, one of the world’s smallest and most endangered cetaceans. With fewer than 30 vaquitas remaining, the group gathered on the shore of the Gulf of California in northern Mexico to try something unprecedented: Capture some of the porpoises, which grow to just 1.5 meters long, in a bid to breed them in captivity. At first, the $5 million effort—named VaquitaCPR—went better than expected, but then a female vaquita died while the researchers were trying to release her. VaquitaCPR leaders abandoned the rescue until an external review examines the circumstances of the death. But the risk of losing another may be too great for a second try. Instead, whether the vaquita, whose population has dropped 90% in the past several years because of illegal fishing net, survives another year now depends on clearing its waters of these nets.

    更新日期:2017-11-19
  • Autoimmune diseases surface after cancer treatment
    Science (IF 37.205) Pub Date : 2017-11-17
    Jennifer Couzin-Frankel

    A new class of cancer drugs is causing autoimmune diseases in some patients, as described last week at the Society for Immunotherapy of Cancer meeting in Oxon Hill, Maryland. Known as checkpoint inhibitors, these medicines rev up the immune system to fight cancer, with sometimes remarkable results. But physicians are now seeing a nasty, if treatable, side effect: the rapid onset of conditions including thyroid disease, colitis, and type 1 diabetes, which all result from an immune attack on the body’s own tissues. As cases mount, researchers across specialties are intensifying efforts to figure out whether certain cancer patients on checkpoint inhibitors are at higher risk—and to learn from this unusual side effect how other autoimmune attacks erupt.

    更新日期:2017-11-19
  • Ancient Australian goes home
    Science (IF 37.205) Pub Date : 2017-11-17
    John Pickrell

    In 1974, in the bone-dry Willandra Lakes Region World Heritage Site in Australia, scientists stumbled on a human skeleton in the dunes of long-vanished Lake Mungo. Dating revealed that “Mungo Man” was up to 42,000 years old, pushing back the first aboriginal habitation of Australia by tens of thousands of years. Now, the celebrated skeleton is going home. Capping a decadeslong custody battle, an aboriginal funeral service hearse set off on 14 November from the Australian National University in Canberra—where the remains were kept since their discovery—on a 700-kilometer drive across the outback to Willandra Lakes. There, they will be turned over to three tribes, which will decide whether to inter the remains or store them and allow research on the bones to continue.

    更新日期:2017-11-19
  • Oldest images of dogs show hunting, leashes
    Science (IF 37.205) Pub Date : 2017-11-17
    David Grimm

    Researchers have discovered what may be the world’s earliest images of dogs in northwestern Saudi Arabia. The depictions, carved into rocks at two sites in the Arabian Desert, appear to date to at least 8000 years ago and feature medium-sized canines—with pricked up ears, short snouts, and curled tails—in hunting scenes. The pictures also feature what appear to be leashes leading from the necks of several dogs to the waists of human hunters. If the dating holds up, this would be the earliest evidence for dog leashes in the archaeological record by thousands of years. Scientists speculate that these early dogs may have helped humans survive in this harsh landscape.

    更新日期:2017-11-19
  • A change of mind
    Science (IF 37.205) Pub Date : 2017-11-17
    Jennifer Couzin-Frankel

    Doctors routinely assess a patient’s risk of heart attack, various cancers, and diabetes, often intervening to slow or stop disease before it strikes. But preventing psychiatric conditions, from anxiety to depression to schizophrenia, has received scant attention. But in recent years, brain specialists have refined their ability to anticipate who’s at highest risk of psychosis—a defining feature of schizophrenia—identifying subtle signs in children and more vivid precursors in late adolescence. And increasingly, researchers feel they’d be derelict not to pursue prevention. A handful of prevention studies are up and running, ranging from cognitive therapies to pregnancy supplements for the fetal brain to psychiatric drugs. Last month, a German pharmaceutical company enrolled the first volunteer into what is intended to be a 300-person, randomized clinical trial, testing an experimental drug to prevent psychosis in those at extremely high risk. It’s believed to be the first time a company has poured millions of dollars into an effort like this one.

    更新日期:2017-11-19
  • Curtailing cascading failures
    Science (IF 37.205) Pub Date : 2017-11-17
    Raissa M. D'Souza

    Cascading behaviors are ubiquitous, from power-grid failures (1) to “flash crashes” in financial markets (2,3) to the spread of political movements such as the “Arab Spring” (4). The causes of these cascades are varied with many unknowns, which make them extremely difficult to predict or contain. Particularly challenging are cascading failures that arise from the reorganization of flows on a network, such as in electric power grids, supply chains, and transportation networks. Here, the network edges (or “links”) have some fixed capacity, and we see that some small disturbances easily dampen out, but other seemingly similar ones lead to massive failures. On page 886 of this issue, Yanget al.(5) establish that a small “vulnerable set” of components in the power grid is implicated in large-scale outages. Although the exact elements in this set vary with operating conditions, they reveal intriguing correlations with network structure.

    更新日期:2017-11-19
  • Feeding frenzy for cancer cells
    Science (IF 37.205) Pub Date : 2017-11-17
    Chi V. Dang

    Cancer cells are thought to undergo metabolic rewiring to scavenge waste products and recycle them as building blocks for growth. On page 941 of this issue, Spinelliet al.(1) report that ammonia could be recycled through glutamate dehydrogenase (GDH)–mediated reductive amination of α-ketoglutarate to produce the amino acid glutamate that, in turn, is converted to other amino acids such as aspartate and proline for biomass production (see the figure). This intriguing evidence of nitrogen fixation by breast cancer cells is reminiscent of nitrogen fixation in bacteria, yeast, and plants mediated by biochemical systems that evolved to harness nitrogen from the atmosphere for amino acid biosynthesis and biomass accumulation (2).

    更新日期:2017-11-19
  • Evolution of neurovirulent Zika virus
    Science (IF 37.205) Pub Date : 2017-11-17
    Gavin Screaton, Juthathip Mongkolsapaya

    In 2015, Zika virus (ZIKV) became headline news after its association with fetal microcephaly (severely reduced head circumference) in Brazil and was declared a public health emergency by the World Health Organization (WHO) (1). However, ZIKV was not new, it was first isolated from the Zika forest, Uganda in 1947 (2). ZIKV incited little interest compared to other flaviviruses, such as dengue virus (DENV), as it was not thought to cause severe disease. ZIKV infections were largely sporadic, and symptoms were usually mild and flu-like, with self-limiting fever, rash, and conjunctivitis. Around 80% of cases were asymptomatic, and epidemic activity had not been described (3). In 2007, large-scale explosive outbreaks of ZIKV infection were described in Micronesia, and the virus spread across the Pacific, reaching South America in 2015, where it rapidly spread through Brazil and neighboring countries (3–5). On page 933 of this issue, Yuanet al.(6) compared sequences of contemporary ZIKV strains with ancestral ZIKV isolates and describe a mutation that increases the neurovirulence of contemporary strains, which they propose underscores the increased pathogenicity of recent outbreaks.

    更新日期:2017-11-19
  • Advancing dengue vaccine development
    Science (IF 37.205) Pub Date : 2017-11-17
    Mark B. Feinberg, Rafi Ahmed

    Dengue virus (DENV) is a member of the viral genusFlavivirus, which also includes yellow fever virus (YFV) and Zika virus (ZIKV). DENV infection is a major and growing global health threat: There are ∼400 million cases of infection, ∼500,000 hospitalizations, and ∼12,500 deaths now estimated to occur each year (1). Dengue represents the most common mosquito-borne disease in humans (1). A remarkable 50% of the world's population now lives in regions where DENV transmission is manifest. Dengue is associated with a wide spectrum of clinical outcomes, ranging from mild febrile illnesses to dengue hemorrhagic fever to the most severe clinical presentation of dengue shock syndrome, which is characterized by profound systemic cytokine activation, vascular leakage, and shock—this carries a high risk of death. On page 929 of this issue, Katzelnicket al.(2) analyzed DENV infection outcome data gleaned from the long-term followup of a cohort of Nicaraguan children (2). They found that the risk of severe dengue disease upon subsequent DENV infection correlated with baseline DENV antibody concentrations (titers), which has implications for DENV vaccination approaches.

    更新日期:2017-11-19
  • Skin color variation in Africa
    Science (IF 37.205) Pub Date : 2017-11-17
    Hua Tang, Gregory S. Barsh

    The remarkable genetic diversity within African populations is both a signature and a storybook of human origins because descendants of the earliest humans who lived in Africa nearly 200,000 years ago have had the longest time to accumulate genetic variation. Although studying genetic diversity in African populations tells us a great deal about human history, there is even more to learn by juxtaposing the genetic diversity with the diversity of heritable traits (phenotypes). Yet, there is a paucity of such studies involving continental Africans (1). On page 887 of this issue, Crawfordet al.(2) demonstrate the potential insights that can come from ameliorating this disparity. They examined skin color variation in 2000 African individuals from different geographic locations and ethnic groups; the range, from light-skinned San hunter-gatherer populations in southern Africa to dark-skinned pastoralist populations in eastern Africa, far exceeds pigmentary diversity anywhere else on the planet (see the figure). Using a genome-wide association study (GWAS) that includes 1600 individuals living in Tanzania, Botswana, or Ethiopia, the authors identified regions of the genome that contribute to skin color variation and carried out a series of analyses to pinpoint the responsible genes.

    更新日期:2017-11-19
  • The promise of plastics from plants
    Science (IF 37.205) Pub Date : 2017-11-17
    Marc A. Hillmyer

    Polymers protect us from the elements, increase the fuel efficiency of cars, protect food from pathogens, help cure disease, and enable renewable-energy technologies. To promote, foster, and enable a sustainable society, we need polymers. Yet polymers can also create serious environmental challenges. Nearly all plastic packaging produced—more than 80 billion kg annually—originates from fossil resources and is disposed of after a relatively short period of use (1,2). An increasing fraction of plastic is recycled or incinerated to recover energy, but most ends up in landfills, littering cities or landscapes, and in the oceans (3). New recycling concepts (4), clean incineration, and the development of polymers that can rapidly degrade (5) will be key to addressing these problems. Shifting from petrochemical feedstocks to renewable resources—making plastics from plants—can also rectify some environmental challenges associated with petrochemical extraction and render plastics production sustainable (see the figure).

    更新日期:2017-11-19
  • The future of plastics recycling
    Science (IF 37.205) Pub Date : 2017-11-17
    Jeannette M. Garcia, Megan L. Robertson

    The environmental consequences of plastic solid waste are visible in the ever-increasing levels of global plastic pollution both on land and in the oceans. But although there are important economic and environmental incentives for plastics recycling, end-of-life treatment options for plastic solid waste are in practice quite limited. Presorting of plastics before recycling is costly and time-intensive, recycling requires large amounts of energy and often leads to low-quality polymers, and current technologies cannot be applied to many polymeric materials. Recent research points the way toward chemical recycling methods with lower energy requirements, compatibilization of mixed plastic wastes to avoid the need for sorting, and expanding recycling technologies to traditionally nonrecyclable polymers.

    更新日期:2017-11-19
  • Designed to degrade
    Science (IF 37.205) Pub Date : 2017-11-17
    Ann-Christine Albertsson, Minna Hakkarainen

    Around 50 years ago, interest arose in making plastics that can degrade in the environment (1). Since then, a stream of research efforts has chased the dream of environmentally friendly materials that disappear without leaving behind fragments or harmful products. Such environmentally degradable plastics are, however, difficult to produce in practice. Durability is one of the requirements for plastic in most technical applications, whereas degradability is necessary for recycling in nature. Although advances are being made in developing degradable materials with suitable properties for particular applications, it is crucial that they are seen as part of a range of approaches and that degradation will always require particular conditions that depend on the specific material and its chemical and physical structure and composition.

    更新日期:2017-11-19
  • Racing for academic glory and patents: Lessons from CRISPR
    Science (IF 37.205) Pub Date : 2017-11-17
    Arti K. Rai, Robert Cook-Deegan

    The much-publicized dispute over patent rights to CRISPR-Cas9 gene-editing technology highlights tensions that have been percolating for almost four decades, since the U.S. Bayh-Dole Act of 1980 invoked patents as a mechanism for promoting commercialization of federally funded research. With the encouragement provided by Bayh-Dole, academic scientists and their research institutions now race in dual competitive domains: the quest for glory in academic research and in the patent sphere. Yet, a robust economic literature (1,2) argues that races are often socially wasteful; the racing parties expend duplicative resources, in terms of both the research itself and the legal fees spent attempting to acquire patents, all in the pursuit of what may be a modest acceleration of invention. For CRISPR, and future races involving broadly useful technologies for which it may set a precedent, the relationship between these competitive domains needs to be parsed carefully. On the basis of legal maneuvers thus far, it appears that the litigants will try for broad rights; public benefit will depend on courts reining them in and, when broad patents slip through, on updating Bayh-Dole's pro-commercialization safeguards with underused features of the Act.

    更新日期:2017-11-19
  • Exploring exoplanets
    Science (IF 37.205) Pub Date : 2017-11-17
    Jennifer Carson

    In 1995, astronomers Michel Mayor and Didier Queloz announced they had detected the first "exoplanet" orbiting a main-sequence star, 51 light years away. Two months later, a team of astronomers led by Geoff Marcy confirmed Mayor's detection and found two more. Within a decade, hundreds of planets orbiting other stars had been detected. NASA's Kepler Telescope, launched into space in 2009, found a few thousand more.The Planet Factory, by Elizabeth Tasker, is the story of these 3000+ planets, "the travel log of how they came to form from dust particles to worlds so diverse that even Hollywood has failed to be weirder."

    更新日期:2017-11-19
  • The scapegoat
    Science (IF 37.205) Pub Date : 2017-11-17
    Jessica Eisner

    In his bookPatient Zero and the Making of the AIDS Epidemic, Richard McKay retraces the fits and starts of early AIDS research and how the evocative concept of a “patient zero” both captured the imagination of the general public and fed into the media hype that fueled speculation about the disease.

    更新日期:2017-11-19
  • General Method of Manipulating Formation, Composition, and Morphology of Solid-Electrolyte Interphases for Stable Li-Alloy Anodes
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Yue Gao, Ran Yi, Yuguang C. Li, Jiangxuan Song, Shuru Chen, Qingquan Huang, Thomas E. Mallouk, Donghai Wang
    更新日期:2017-11-19
  • Direct and Delayed Dynamics in Electron-Induced Surface Reaction
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Oliver MacLean, Kai Huang, Lydie Leung, John C. Polanyi
    更新日期:2017-11-19
  • Ionic Liquid Droplet Microreactor for Catalysis Reactions Not at Equilibrium
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Ming Zhang, Rammile Ettelaie, Tao Yan, Suojiang Zhang, Fangqin Cheng, Bernard P. Binks, Hengquan Yang
    更新日期:2017-11-19
  • DNA Aptamer-Based Activatable Probes for Photoacoustic Imaging in Living Mice
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Jingjing Zhang, Lukas P. Smaga, Nitya Sai Reddy Satyavolu, Jefferson Chan, Yi Lu
    更新日期:2017-11-19
  • Fingerprints of Modified RNA Bases from Deep Sequencing Profiles
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Anna M. Kietrys, Willem A. Velema, Eric T. Kool
    更新日期:2017-11-19
  • Enantiomeric Recognition of d- and l-Lactate by CEST with the Aid of a Paramagnetic Shift Reagent
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Lei Zhang, André F. Martins, Piyu Zhao, Michael Tieu, David Esteban-Gómez, Gregory T. McCandless, Carlos Platas-Iglesias, A. Dean Sherry
    更新日期:2017-11-19
  • Mediating Reductive Charge Shift Reactions in Electron Transport Chains
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Maximilian Wolf, Carmen Villegas, Olga Trukhina, Juan Luis Delgado, Tomás Torres, Nazario Martín, Timothy Clark, Dirk M. Guldi
    更新日期:2017-11-19
  • Cysteine Linkages Accelerate Electron Flow through Tetra-Heme Protein STC
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Xiuyun Jiang, Zdenek Futera, Md. Ehesan Ali, Fruzsina Gajdos, Guido F. von Rudorff, Antoine Carof, Marian Breuer, Jochen Blumberger
    更新日期:2017-11-19
  • Iminium Catalysis inside a Self-Assembled Supramolecular Capsule: Scope and Mechanistic Studies
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Thomas M. Bräuer, Qi Zhang, Konrad Tiefenbacher
    更新日期:2017-11-19
  • Crystalline Coordination Networks of Zero-Valent Metal Centers: Formation of a 3-Dimensional Ni(0) Framework with m-Terphenyl Diisocyanides
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Douglas W. Agnew, Ida M. DiMucci, Alejandra Arroyave, Milan Gembicky, Curtis E. Moore, Samantha N. MacMillan, Arnold L. Rheingold, Kyle M. Lancaster, Joshua S. Figueroa
    更新日期:2017-11-19
  • Real-Time Observation of Nonadiabatic Bifurcation Dynamics at a Conical Intersection
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Kyung Chul Woo, Do Hyung Kang, Sang Kyu Kim
    更新日期:2017-11-19
  • Generating System-Level Responses from a Network of Simple Synthetic Replicators
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Jan W. Sadownik, Tamara Kosikova, Douglas Philp
    更新日期:2017-11-19
  • Chemical Design and Example of Transparent Bipolar Semiconductors
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Takeshi Arai, Soshi Iimura, Junghwan Kim, Yoshitake Toda, Shigenori Ueda, Hideo Hosono
    更新日期:2017-11-19
  • Electronic Effects on Room-Temperature, Gas-Phase C–H Bond Activations by Cluster Oxides and Metal Carbides: The Methane Challenge
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Helmut Schwarz, Sason Shaik, Jilai Li
    更新日期:2017-11-19
  • Selective ortho C–H Activation of Pyridines Directed by Lewis Acidic Boron of PBP Pincer Iridium Complexes
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Wei-Chun Shih, Oleg V. Ozerov
    更新日期:2017-11-19
  • Hierarchical Self-Assembly of a Copolymer-Stabilized Coacervate Protocell
    J. Am. Chem. Soc. (IF 13.858) Pub Date : 2017-11-17
    Alexander F. Mason, Bastiaan C. Buddingh’, David S. Williams, Jan C. M. van Hest
    更新日期:2017-11-19
  • Continuum tuning of nanoparticle interfacial properties by dynamic covalent exchange
    Chem. Sci. (IF 8.668) Pub Date : 2017-11-17
    William Edwards, Nicolas Marro, Grace Turner, Euan R. Kay
    更新日期:2017-11-19
  • Archaeology: Inequality has deep roots in Eurasia
    Nature (IF 40.137) Pub Date : 2017-11-15
    Michelle Elliott

    A study of 64 archaeological sites across four continents shows that the growth of agricultural and political systems provoked economic disparities, more so in Eurasia than in North America.

    更新日期:2017-11-17
  • Cancer immunotherapy: The dark side of PD-1 receptor inhibition
    Nature (IF 40.137) Pub Date : 2017-11-15
    Aya Ludin, Leonard I. Zon

    Inhibiting the protein PD-1 can activate T cells that trigger immune responses against tumour cells. But it emerges that, in mice, this immunotherapy exacerbates a cancer that involves the T cells themselves.

    更新日期:2017-11-17
  • Microbiota: A high-pressure situation for bacteria
    Nature (IF 40.137) Pub Date : 2017-11-15
    David A. Relman

    Analyses in mice suggest that dietary salt increases blood pressure partly by affecting some of the microbes that inhabit the gut. The implications of this work for hypertension warrant further study in humans.

    更新日期:2017-11-17
  • Visualization of chemical modifications in the human 80S ribosome structure
    Nature (IF 40.137) Pub Date : 2017-11-15
    S. Kundhavai Natchiar, Alexander G. Myasnikov, Hanna Kratzat, Isabelle Hazemann, Bruno P. Klaholz

    A high-resolution structure of the human ribosome determined by cryo-electron microscopy visualizes numerous RNA modifications that are concentrated at functional sites with an extended shell, and suggests the possibility of designing more specific ribosome-targeting drugs.

    更新日期:2017-11-17
  • Salt-responsive gut commensal modulates TH17 axis and disease
    Nature (IF 40.137) Pub Date : 2017-11-15
    Nicola Wilck, Mariana G. Matus, Sean M. Kearney, Scott W. Olesen, Kristoffer Forslund, Hendrik Bartolomaeus, Stefanie Haase, Anja Mähler, András Balogh, Lajos Markó, Olga Vvedenskaya, Friedrich H. Kleiner, Dmitry Tsvetkov, Lars Klug, Paul I. Costea, Shinichi Sunagawa, Lisa Maier, Natalia Rakova, Valentin Schatz, Patrick Neubert, Christian Frätzer, Alexander Krannich, Maik Gollasch, Diana A. Grohme, Beatriz F. Côrte-Real, Roman G. Gerlach, Marijana Basic, Athanasios Typas, Chuan Wu, Jens M. Titze, Jonathan Jantsch, Michael Boschmann, Ralf Dechend, Markus Kleinewietfeld, Stefan Kempa, Peer Bork, Ralf A. Linker, Eric J. Alm, Dominik N. Müller

    High salt intake changed the gut microbiome and increased TH17 cell numbers in mice, and reduced intestinal survival of Lactobacillus species, increased the number of TH17 cells and increased blood pressure in humans.

    更新日期:2017-11-17
  • Greater post-Neolithic wealth disparities in Eurasia than in North America and Mesoamerica
    Nature (IF 40.137) Pub Date : 2017-11-15
    Timothy A. Kohler, Michael E. Smith, Amy Bogaard, Gary M. Feinman, Christian E. Peterson, Alleen Betzenhauser, Matthew Pailes, Elizabeth C. Stone, Anna Marie Prentiss, Timothy J. Dennehy, Laura J. Ellyson, Linda M. Nicholas, Ronald K. Faulseit, Amy Styring, Jade Whitlam, Mattia Fochesato, Thomas A. Foor, Samuel Bowles

    How wealth is distributed among households provides insight into the fundamental characters of societies and the opportunities they afford for social mobility. However, economic inequality has been hard to study in ancient societies for which we do not have written records, which adds to the challenge of placing current wealth disparities into a long-term perspective. Although various archaeological proxies for wealth, such as burial goods or exotic or expensive-to-manufacture goods in household assemblages, have been proposed, the first is not clearly connected with households, and the second is confounded by abandonment mode and other factors. As a result, numerous questions remain concerning the growth of wealth disparities, including their connection to the development of domesticated plants and animals and to increases in sociopolitical scale. Here we show that wealth disparities generally increased with the domestication of plants and animals and with increased sociopolitical scale, using Gini coefficients computed over the single consistent proxy of house-size distributions. However, unexpected differences in the responses of societies to these factors in North America and Mesoamerica, and in Eurasia, became evident after the end of the Neolithic period. We argue that the generally higher wealth disparities identified in post-Neolithic Eurasia were initially due to the greater availability of large mammals that could be domesticated, because they allowed more profitable agricultural extensification, and also eventually led to the development of a mounted warrior elite able to expand polities (political units that cohere via identity, ability to mobilize resources, or governance) to sizes that were not possible in North America and Mesoamerica before the arrival of Europeans. We anticipate that this analysis will stimulate other work to enlarge this sample to include societies in South America, Africa, South Asia and Oceania that were under-sampled or not included in this study.

    更新日期:2017-11-17
  • Genome sequence of the progenitor of the wheat D genome Aegilops tauschii
    Nature (IF 40.137) Pub Date : 2017-11-15
    Ming-Cheng Luo, Yong Q. Gu, Daniela Puiu, Hao Wang, Sven O. Twardziok, Karin R. Deal, Naxin Huo, Tingting Zhu, Le Wang, Yi Wang, Patrick E. McGuire, Shuyang Liu, Hai Long, Ramesh K. Ramasamy, Juan C. Rodriguez, Sonny L. Van, Luxia Yuan, Zhenzhong Wang, Zhiqiang Xia, Lichan Xiao, Olin D. Anderson, Shuhong Ouyang, Yong Liang, Aleksey V. Zimin, Geo Pertea, Peng Qi, Jeffrey L. Bennetzen, Xiongtao Dai, Matthew W. Dawson, Hans-Georg Müller, Karl Kugler, Lorena Rivarola-Duarte, Manuel Spannagl, Klaus F. X. Mayer, Fu-Hao Lu, Michael W. Bevan, Philippe Leroy, Pingchuan Li, Frank M. You, Qixin Sun, Zhiyong Liu, Eric Lyons, Thomas Wicker, Steven L. Salzberg, Katrien M. Devos, Jan Dvořák

    Aegilops tauschii is the diploid progenitor of the D genome of hexaploid wheat (Triticum aestivum, genomes AABBDD) and an important genetic resource for wheat. The large size and highly repetitive nature of the Ae. tauschii genome has until now precluded the development of a reference-quality genome sequence. Here we use an array of advanced technologies, including ordered-clone genome sequencing, whole-genome shotgun sequencing, and BioNano optical genome mapping, to generate a reference-quality genome sequence for Ae. tauschii ssp. strangulata accession AL8/78, which is closely related to the wheat D genome. We show that compared to other sequenced plant genomes, including a much larger conifer genome, the Ae. tauschii genome contains unprecedented amounts of very similar repeated sequences. Our genome comparisons reveal that the Ae. tauschii genome has a greater number of dispersed duplicated genes than other sequenced genomes and its chromosomes have been structurally evolving an order of magnitude faster than those of other grass genomes. The decay of colinearity with other grass genomes correlates with recombination rates along chromosomes. We propose that the vast amounts of very similar repeated sequences cause frequent errors in recombination and lead to gene duplications and structural chromosome changes that drive fast genome evolution.

    更新日期:2017-11-17
  • Structural basis of nucleotide sugar transport across the Golgi membrane
    Nature (IF 40.137) Pub Date : 2017-11-15
    Joanne L. Parker, Simon Newstead

    Glycosylation is a fundamental cellular process that, in eukaryotes, occurs in the lumen of both the Golgi apparatus and the endoplasmic reticulum. Nucleotide sugar transporters (NSTs) are an essential component of the glycosylation pathway, providing the diverse range of substrates required for the glycosyltransferases. NSTs are linked to several developmental and immune disorders in humans, and in pathogenic microbes they have an important role in virulence. How NSTs recognize and transport activated monosaccharides, however, is currently unclear. Here we present the crystal structure of an NST, the GDP–mannose transporter Vrg4, in both the substrate-free and the bound states. A hitherto unobserved requirement of short-chain lipids in activating the transporter supports a model for regulation within the highly dynamic membranes of the Golgi apparatus. Our results provide a structural basis for understanding nucleotide sugar recognition, and provide insights into the transport and regulatory mechanism of this family of intracellular transporters.

    更新日期:2017-11-17
  • Quantitative microbiome profiling links gut community variation to microbial load
    Nature (IF 40.137) Pub Date : 2017-11-15
    Doris Vandeputte, Gunter Kathagen, Kevin D’hoe, Sara Vieira-Silva, Mireia Valles-Colomer, João Sabino, Jun Wang, Raul Y. Tito, Lindsey De Commer, Youssef Darzi, Séverine Vermeire, Gwen Falony, Jeroen Raes

    Current sequencing-based analyses of faecal microbiota quantify microbial taxa and metabolic pathways as fractions of the sample sequence library generated by each analysis. Although these relative approaches permit detection of disease-associated microbiome variation, they are limited in their ability to reveal the interplay between microbiota and host health. Comparative analyses of relative microbiome data cannot provide information about the extent or directionality of changes in taxa abundance or metabolic potential. If microbial load varies substantially between samples, relative profiling will hamper attempts to link microbiome features to quantitative data such as physiological parameters or metabolite concentrations. Saliently, relative approaches ignore the possibility that altered overall microbiota abundance itself could be a key identifier of a disease-associated ecosystem configuration. To enable genuine characterization of host–microbiota interactions, microbiome research must exchange ratios for counts. Here we build a workflow for the quantitative microbiome profiling of faecal material, through parallelization of amplicon sequencing and flow cytometric enumeration of microbial cells. We observe up to tenfold differences in the microbial loads of healthy individuals and relate this variation to enterotype differentiation. We show how microbial abundances underpin both microbiota variation between individuals and covariation with host phenotype. Quantitative profiling bypasses compositionality effects in the reconstruction of gut microbiota interaction networks and reveals that the taxonomic trade-off between Bacteroides and Prevotella is an artefact of relative microbiome analyses. Finally, we identify microbial load as a key driver of observed microbiota alterations in a cohort of patients with Crohn’s disease, here associated with a low-cell-count Bacteroides enterotype (as defined through relative profiling).

    更新日期:2017-11-17
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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