11 November 2005 Volume 310 Number 5750
现代欧洲人的祖先
对来自早期欧洲农民骨骼和牙齿的线粒体DNA的首次详细分析表明，这些大约在7500年前将农业带到中部欧洲的农民，看起来对现代欧洲人的遗传构成没有大的影响。这项工作加强了一种观点，既中部欧洲人大部分的祖先是大约40,000年前到了欧洲的“旧石器时代”的狩猎者-采集者，而不是在几万年后的新石器时代来到欧洲的第一批农民。来自德国、英国、以及爱沙尼亚的科学家从来自德国、奥地利和匈牙利16个地点的24个早期农民骨骼中取出线粒体DNA，并对其进行了分析。这24个早期农民中的6个属于一个极为罕见的"N1a"人类谱系。24个骨骼中就有6个属于这个谱系的发现表明，这些早期农民在现代欧洲人口中没有留下大的遗传印记。可能是一小组先驱农民将农业带到欧洲其他地方。一旦农业在这些地方立足，附近的狩猎者-采集者适应了这个新的文化，他们的人数比原始的农民多得多，从而冲淡了外来者的N1a 频率，使其降低到现代欧洲人的水平，这些作者说。
报告：Ancient DNA from the First European Farmers in 7500-Year-Old Neolithic Sites, Wolfgang Haak, et al.
两个互相对抗的食欲激素
研究人员在大鼠身上发现了一个新的降低食欲的激素，看似矛盾的是，这个激素是增加食欲的激素ghrelin的一个近亲，它是由衍生ghrelin的同一个前体蛋白衍生而来。Jian V. Zhang和同事用生物信息学的方法，通过比较不同生物体的ghrelin基因的序列， 发现了他们命名为"obestatin"的激素。用大鼠做的实验显示，这个激素的一个合成版本有与ghrelin相反的生理作用，它降低了食物摄取。Obestatin与受体GPR39结合并将其激活，这个受体与ghrelin的受体有同样的序列，但是有不同的形式。文章作者写道，"对能量稳态和体重控制的微妙平衡中ghrelin 和obestatin的作用的更好的了解，也许是成功地治疗肥胖症的关键"。一篇相关的研究评述指出，obestatin对大鼠体重的作用比较微妙，obestatin对人体是否有作用还有待研究。
报告：Obestatin, a Peptide Encoded by the Ghrelin Gene, Opposes Ghrelin's Effects on Food Intake, Jian V. Zhang, et al.
研究评述：Separation of Conjoined Hormones Yields Appetite Rivals, Ruben Nogueiras and Matthias Tschop
抑制发炎的小分子
科学家发现了一个能抑制免疫系统调节蛋白TNF-α的小分子，TNF-α在类风湿性关节炎、克罗恩病、以及牛皮癣等疾病中起作用。人们已经知道三个TNF-α子单元的组合与TNF受体结合激活炎症反应。针对TNF-α或其受体的可溶形式的抗体有治疗效果，但如果能找到一个小分子药物则更好。虽然防止TNF-α形成三聚体是这种药物工作的一个可能路径，但是设计一个针对确切的蛋白质-蛋白质相互作用的分子药物一直是一个挑战。现在Molly He和同事报告了一个小分子抑制物，它通过分离TNF-α三聚体起作用。这个抑制物与完整的有生物活性的三聚体结合，加速了一个子单元的分离，然后与剩下的两个TNF-α子单元形成一个复合体。
研究文章：Small-Molecule Inhibition of TNF-α, Molly M. He, et al.
平稳地在月球上着陆
虽然阿波罗11号的月球之行从各个方面来看都是成功的，但是研究人员不希望在未来再重复那次着陆过程本身。Maria Zuber和Ian Garrick-Bethell在一篇研究评述中解释说，当阿姆斯特朗在月球上寻找一个能平稳着陆的地点时，他很吃惊地看到一个被许多大石头围绕的足球场大小的陨石坑。尽管飞船安全地着陆了，但文章作者说，在许多国家都在准备登月之际，一件事是肯定的：“我们不会再那么干”。他们描述了什么使火星探索者和火星探测车在那个红色行星的着陆如此地成功，以及月球表面的哪些我们还需要有进一步了解才能设计出不管是载人飞船还是机器人的同样成功的月球着陆。
研究评述：What Do We Need to Know to Land on the Moon Again?, Maria T. Zuber and Ian Garrick-Bethell
光合作用的一个中间态
德国研究人员发现了光合作用中一个不易观察的氧气生产的中间态。一篇相关的研究评述指出，尽管人们已经在设计太阳能转换器上努力了几十年，但是人工的太阳能系统与自然的光合作用相比，能获取的太阳能微不足道。对自然过程的更好的了解也许最终能帮助研究人员设计更有效的捕获太阳能的系统。在光合作用中，氧生产的能量来自太阳光，并且由一个与蛋白质photosystem II结合的锰复合体催化。在这个过程的经典模型中，这个锰复合体经历5个氧化状态，但只有从S0到S3的4个状态在试验中观察到了。现在Michael Haumann和同事通过用时间分辨的X射线试验来实时监测光合作用的双氧生产，他们发现了S4这个中间态。与过去的假设相反，这个状态是通过一个去质子化过程、而不是一个电子转移过程形成的。
报告：Photosynthetic O2 Formation Tracked by Time-Resolved X-ray Experiments, Michael Plattens, et al.
研究评述：The Photosynthesis "Oxygen Clock" Gets a New Number, James E. Penner-Hahn and Charles F. Yocum
解读生命之树
达尔文用了“生命之树”这个比喻来解释他的进化论，一篇研究评述的作者指出，这个比喻现在被许多人错误地理解，作者提出进化树或种系树应该在公众对进化论的理解中占更重要的地位。在种系树上，活的物种从时间上反向追溯到共同的祖先，就像树的不同枝叶回溯到同一个主干枝上。作者说，对种系树的误解导致了对进化论核心的困惑，认为活的物种是（带有修正地）从共同祖先继承下来的产物。学习正确地阅读种系树会使我们清楚地认识到为什么广泛认为的进化是一个从初级到高级物种的线性延续的观点是不准确的。随着科学家能更好地解读种系树，作者希望社会上越来越的人将能认识共同祖先的大量证据以及进化生物学的科学严谨性。
研究评述：The Tree-Thinking Challenge, David A. Baum, Stacey DeWitt Smith, and Samuel S. S. Donovan
Table of Contents
RESEARCH
This Week in Science
Bigger in the Middle * Oxo Above, Sulfur Below * Looking Through HOOPs * Transitional Forcing * Climate Change and Ancient Plant Ranges * Piece by Piece * Dueling Hunger Hormones? * Modeling Complexity * Mainly a Cultural Legacy * Targeting TNF-α Interactions * Detailed View of the HIV Spike * A Time to Grow, A Time to Crop * Real-Time Photosystem Analysis * A Model Forest of Carbon Storage
Science 11 November 2005: 939 [Full Text]
Editors' Choice: Highlights of the recent literature
IMMUNOLOGY: An Inflammatory Lineage * CLIMATE SCIENCE: Warmer and Drier * BIOCHEMISTRY: New Activity, Old Enzyme * GEOCHEMISTRY: Reversing Crystal Growth * APPLIED PHYSICS: Patterns of Light * STKE: Bacterial Pheromone for Sex and Abstinence
Science 11 November 2005: 945 [Full Text]
Review Pattern-Oriented Modeling of Agent-Based Complex Systems: Lessons from Ecology
Volker Grimm, Eloy Revilla, Uta Berger, Florian Jeltsch, Wolf M. Mooij, Steven F. Railsback, Hans-Hermann Thulke, Jacob Weiner, Thorsten Wiegand, and Donald L. DeAngelis
Science 11 November 2005: 987-991. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Brevia Multiple Transatlantic Introductions of the Western Corn Rootworm
Nicholas Miller, Arnaud Estoup, Stefan Toepfer, Denis Bourguet, Laurent Lapchin, Sylvie Derridj, Kyung Seok Kim, Philippe Reynaud, Lorenzo Furlan, and Thomas Guillemaud
Science 11 November 2005: 992. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Research Articles Transient Floral Change and Rapid Global Warming at the Paleocene-Eocene Boundary
Scott L. Wing, Guy J. Harrington, Francesca A. Smith, Jonathan I. Bloch, Douglas M. Boyer, and Katherine H. Freeman
Science 11 November 2005: 993-996. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Obestatin, a Peptide Encoded by the Ghrelin Gene, Opposes Ghrelin's Effects on Food Intake
Jian V. Zhang, Pei-Gen Ren, Orna Avsian-Kretchmer, Ching-Wei Luo, Rami Rauch, Cynthia Klein, and Aaron J. W. Hsueh
Science 11 November 2005: 996-999. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Reports A Thiolate-Ligated Nonheme Oxoiron(IV) Complex Relevant to Cytochrome P450
Michael R. Bukowski, Kevin D. Koehntop, Audria Stubna, Emile L. Bominaar, Jason A. Halfen, Eckard Münck, Wonwoo Nam, and Lawrence Que, Jr.
Science 11 November 2005: 1000-1002.
Published online 27 October 2005 [DOI: 10.1126/science.1119092] (in Science Express Reports) [Abstract] [Full Text] [PDF] [Supporting Online Material]
Direct Visualization of the Formation of Single-Molecule Conjugated Copolymers
Hiroshi Sakaguchi, Hisashi Matsumura, Hui Gong, and Abdelkarim M. Abouelwafa
Science 11 November 2005: 1002-1006. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Structural Observation of the Primary Isomerization in Vision with Femtosecond-Stimulated Raman
Philipp Kukura, David W. McCamant, Sangwoon Yoon, Daniel B. Wandschneider, and Richard A. Mathies
Science 11 November 2005: 1006-1009. [Abstract] [Full Text] [PDF] [Supporting Online Material]
The Mid-Pleistocene Transition in the Tropical Pacific
Martín Medina-Elizalde and David W. Lea
Science 11 November 2005: 1009-1012.
Published online 13 October 2005 [DOI: 10.1126/science.1115933] (in Science Express Reports) [Abstract] [Full Text] [PDF] [Supporting Online Material]
Recent Ice-Sheet Growth in the Interior of Greenland
Ola M. Johannessen, Kirill Khvorostovsky, Martin W. Miles, and Leonid P. Bobylev
Science 11 November 2005: 1013-1016.
Published online 20 October 2005 [DOI: 10.1126/science.1115356] (in Science Express Reports) [Abstract] [Full Text] [PDF] [Supporting Online Material]
Ancient DNA from the First European Farmers in 7500-Year-Old Neolithic Sites
Wolfgang Haak, Peter Forster, Barbara Bramanti, Shuichi Matsumura, Guido Brandt, Marc Tänzer, Richard Villems, Colin Renfrew, Detlef Gronenborn, Kurt Werner Alt, and Joachim Burger
Science 11 November 2005: 1016-1018. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Photosynthetic O2 Formation Tracked by Time-Resolved X-ray Experiments
M. Haumann, P. Liebisch, C. Müller, M. Barra, M. Grabolle, and H. Dau
Science 11 November 2005: 1019-1021. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Small-Molecule Inhibition of TNF-
Molly M. He, Annemarie Stroustrup Smith, Johan D. Oslob, William M. Flanagan, Andrew C. Braisted, Adrian Whitty, Mark T. Cancilla, Jun Wang, Alexey A. Lugovskoy, Josh C. Yoburn, Amy D. Fung, Graham Farrington, John K. Eldredge, Eric S. Day, Leslie A. Cruz, Teresa G. Cachero, Stephan K. Miller, Jessica E. Friedman, Ingrid C. Choong, and Brian C. Cunningham
Science 11 November 2005: 1022-1025. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Structure of a V3-Containing HIV-1 gp120 Core
Chih-chin Huang, Min Tang, Mei-Yun Zhang, Shahzad Majeed, Elizabeth Montabana, Robyn L. Stanfield, Dimiter S. Dimitrov, Bette Korber, Joseph Sodroski, Ian A. Wilson, Richard Wyatt, and Peter D. Kwong
Science 11 November 2005: 1025-1028. [Abstract] [Full Text] [PDF] [Supporting Online Material]
Species Loss and Aboveground Carbon Storage in a Tropical Forest
Daniel E. Bunker, Fabrice DeClerck, Jason C. Bradford, Robert K. Colwell, Ivette Perfecto, Oliver L. Phillips, Mahesh Sankaran, and Shahid Naeem
Science 11 November 2005: 1029-1031.
Published online 20 October 2005 [DOI: 10.1126/science.1117682] (in Science Express Reports) [Abstract] [Full Text] [PDF] [Supporting Online Material]
The Pseudo-Response Regulator Ppd-H1 Provides Adaptation to Photoperiod in Barley
Adrian Turner, James Beales, Sébastien Faure, Roy P. Dunford, and David A. Laurie
Science 11 November 2005: 1031-1034. [Abstract] [Full Text] [PDF] [Supporting Online Material]
COMMENTARY
Editorial
Biodiversity Science Evolves
Rodolfo Dirzo and Michel Loreau
Science 11 November 2005: 943. [Summary] [PDF]
Letters Balancing Risk and Recovery Iris Lindberg ; Suggesting Reviewers Affects Outcome? David F. Ackerley; and K. Brad Wray ; Correcting Temperature Data Sets John R. Christy, Roy W. Spencer;, Carl A. Mears, Frank J. Wentz;, Steven C. Sherwood, and John R. Lanzante ; Causation, Vioxx, and Legal Issues Michael D. Green ; Illusory Statistics Robert M. Ewers ; Corrections and Clarifications
Science 11 November 2005: 971. [Full Text] [PDF]
Policy Forum SCIENCE AND LAW:
WMD Sensors--Search and Seizure
Don Prosnitz
Science 11 November 2005: 978. [Summary] [Full Text] [PDF]
Books et al. PUBLIC HEALTH:
A Vaccine Disaster and Its Fateful Shadow
Olen Kew
Science 11 November 2005: 975. [Summary] [Full Text] [PDF]
PHYSICS:
A Comical Look at Real Physics
Sam Kean
Science 11 November 2005: 976. [Summary] [Full Text] [PDF]
Books Received
Science 11 November 2005: 976. [Summary]
Perspectives EVOLUTION:
The Tree-Thinking Challenge
David A. Baum, Stacey DeWitt Smith, and Samuel S. S. Donovan
Science 11 November 2005: 979-980. [Summary] [Full Text] [PDF] [Supporting Online Material]
CHEMISTRY:
Following the Flow of Energy in Biomolecules
Paul M. Champion
Science 11 November 2005: 980-982. [Summary] [Full Text] [PDF]
BIOCHEMISTRY:
The Photosynthesis "Oxygen Clock" Gets a New Number
James E. Penner-Hahn and Charles F. Yocum
Science 11 November 2005: 982-983. [Summary] [Full Text] [PDF]
PLANETARY SCIENCE:
Enhanced: What Do We Need to Know to Land on the Moon Again?
Maria T. Zuber and Ian Garrick-Bethell
Science 11 November 2005: 983-985. [Summary] [Full Text] [PDF]
BIOMEDICINE:
Separation of Conjoined Hormones Yields Appetite Rivals
Ruben Nogueiras and Matthias Tschöp
Science 11 November 2005: 985-986. [Summary] [Full Text] [PDF]
NEWS
News of the Week PUBLIC HEALTH:
Pandemic or Not, Experts Welcome Bush Flu Plan
Jocelyn Kaiser
Science 11 November 2005: 952-953. [Summary] [Full Text] [PDF]
HURRICANE KATRINA:
Levees Came Up Short, Researchers Tell Congress
Eli Kintisch
Science 11 November 2005: 953-955. [Summary] [Full Text] [PDF]
ITER:
Fusion Leaders Make a Diplomatic Choice
Daniel Clery
Science 11 November 2005: 955. [Summary] [Full Text] [PDF]
ASTROPHYSICS:
Surprise Neutron Star Suggests Black Holes Are Hard to Make
Govert Schilling
Science 11 November 2005: 956-957. [Summary] [Full Text] [PDF]
NATIONAL SCIENCE FOUNDATION:
Board Suggests How to Thrive Under Stress
Jeffrey Mervis
Science 11 November 2005: 956. [Summary] [Full Text] [PDF]
U.S. HIGHER EDUCATION:
Schools Cheer Rise in Foreign Students
Yudhijit Bhattacharjee
Science 11 November 2005: 957. [Summary] [Full Text] [PDF]
EPIDEMIOLOGY:
Russian Cancer Study Adds to the Indictment of Low-Dose Radiation
Richard Stone
Science 11 November 2005: 959. [Summary] [Full Text] [PDF]
News Focus BIOGEOGRAPHY:
Is Everything Everywhere?
John Whitfield
Science 11 November 2005: 960-961. [Summary] [Full Text] [PDF]
PROFILE: SUSAN GREENFIELD:
The Baroness and the Brain
John Bohannon
Science 11 November 2005: 962-963. [Summary] [Full Text] [PDF]
EVOLUTION:
Ancient DNA Yields Clues to the Puzzle of European Origins
Michael Balter
Science 11 November 2005: 964-965. [Summary] [Full Text] [PDF]
DRUG RESEARCH:
Trying to Catch Troublemakers With a Metabolic Profile
Gunjan Sinha
Science 11 November 2005: 965-966. [Summary] [Full Text] [PDF]
PALEONTOLOGY:
Tyrannosaurus rex Gets Sensitive
Erik Stokstad
Science 11 November 2005: 966-967. [Summary] [Full Text] [PDF]
Products New Products
Science 11 November 2005: 1035. [Summary] [PDF]
NetWatch
EDUCATION: Brush Up Your Einstein * RESOURCES: Keeping Tabs on Rare Diseases * IMAGES: Out of the Kiln * FUN: From Earth to the Moon * EDUCATION: Sick at Heart Science 11 November 2005: 949 [Full Text]
ScienceScope
Hot on the Toxin Trail * The Endless Battle Over Stem Cells * Europe to Cut Lab Animal Tests * U.S. Science Budgets Emerge Science 11 November 2005: 955 [Full Text]
Random Samples
The State of Africa's Lakes * Hellenistic Engineering * Latest in Translation * Who's No. 1? * Awards * On Campus * A Life In Science * Misconduct * Nonprofit World
Science 11 November 2005: 968 [Full Text]
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