15 September 2006 Vol 313, Issue 5793, Pages 1537-1647
美洲大陆最古老的文字
在墨西哥Veracruz 发现的刻有规整图案的石块被认为是北美最古老的文字的例子。该石块是在西方世界最古老的噢美克(Olmec)文明过去的首都附近的采碎石场中发现的。 Carmen Rodriguez Martinez和Ponciano Ortiz Ceballos带领的一个多学科小组确定，这个石块的年代为公元100年左右，比过去在中美洲文明地区发现的要老，中美洲文明地区指从墨西哥中部到哥斯达黎加东北边界的区域。这些纹像(glyphs)，或表示象征的图形，与其他看来像文字的噢美克图案类似。噢美克人曾创造了高达8英尺的巨大人头雕塑。文章合作者Stephen Houston 说，“这个石块显示了该社会的一个新方面，既记账和记录的可能性。”
研究文章：Oldest Writing in the New World, Ma. del Carmen Rodríguez Martínez, et al.
科学家测出杨树基因组草图
科学家首次测序了一种名为黑三角叶杨的树的基因组，使他们能够开始寻找哪些遗传密码形成了长活的、木质植物，而不是像拟南芥那样的开花植物。树在一个地点生活几十年甚至上百年，周围的环境不断地变化，它们一定有非凡的生存战略。Gerald Tuskan 和他的合作者指出，树覆盖了地球陆地表面的30%，它们必须制造木制材料，在长距离上协调信号和营养，经历季节变化和其它气候周期而存活。树的基因组将为它们如何完成这些高招提供线索。Tuskan和他的国际小组用了散弹法和序列组装，将基因组分成片段，测序这些片断，然后靠比较端部的序列将它们组装起来。他们将这个方法与遗传图谱结合起来，遗传图谱是指标明了遗传标记位置的大致基因组，组装出Populus trichocarpa 的基因组草图。结果显示，该树经历了两个整个基因组复制事件，其中一个发生的时间与拟南芥中发生的同时。文章作者报告说，这个杨树的基因组看起来必拟南芥的基因组进化得慢。与拟南芥相比，杨树有抵抗疾病、分生组织（根和幼芽）发育、代谢输运、以及合成植物细胞壁的纤维素和木质素的扩展的基因库。
研究文章：The Genome of Black Cottonwood, Populus trichocarpa (Torr. & Gray), G. A. Tuskan, et al.
达尔福尔死亡人数比报道的要高
根据有限的数据做出的一个保守和科学的估计指出，在苏丹达尔福尔地区的武装冲突中死亡的人数达几十万，而不是过去报道的几万人。苏丹西部的死亡和被迫移民开始于2003年2月。John Hagan和Alberto Palloni解释说，准确的死亡统计为了解这个悲剧以及大屠杀程度的提供了方法。但是战乱的环境使人们不可能做彻底的调查，所以研究人员用来自达尔福尔西部“内部被迫离开人们”的营地中进行调查所得到的最好的数据。在苏达达尔福尔西部、北部、和南部的每个州中约各有100万人被迫离开，研究人员估计冲突导致至少20万人死亡。
政策论坛：Death in Darfur, John Hagan and Alberto Palloni
单个基因抵抗单个病毒
一个单个基因缺陷也许是单纯疱疹脑炎(herpes simplex encephalitis)的罪魁祸首，这一发现也许对我们如何思考传染的遗传抵抗有令人惊讶的影响，它也可能帮助解释为什么只有很少的人患这类脑炎，尽管该病毒也引起世界范围80%的未成年人感染唇疱疹。有的单个基因缺陷引起罕见的、但传播范围广的使人易患多种感染的免疫缺陷，多个基因的作用使健康人群易受一种常见疾病的感染。但是Armanda Casrouge和同事现在揭示了另一种可能性：一个单个基因突变与对一个单个疾病的免疫抵抗力的一对一的关系。这些研究人员在一个叫UNC-93B 的蛋白中发现了一个罕见的、使两个儿童易患单纯疱疹脑炎突变，该蛋白被认为与细胞的抗病毒响应有关。这两位儿童对其它的病原体有强的免疫应答，表明该基因突变只让他们对单纯疱疹病毒1变得易感。
科学特快报告：Herpes Simplex Virus Encephalitis in Human UNC-93B Deficiency, Armanda Casrouge, et al.
土卫六的缺失乙烷找到了？
来自卡西尼飞船的新数据提出，土卫六泰坦的一个大的极地云层也许含有该卫星“缺失”的乙烷。有关土卫六大气化学的预测使科学家认为该卫星的表面会被乙烷海洋覆盖，但是其表面看上去大部分是乙烷潮湿的丘。现在，Caitlin Griffith和同事说，一个的徘徊在土卫六北极上空的巨大的云也许包含了大部分预测的乙烷。研究人员说，在冰冷的条件下，乙烷的冰和雪能在极地凝聚，虽然目前还没有极地乙烷冰盖的直接证据。卡西尼上的可视红外绘图光谱仪探测到云也许是通过与地球冬天极地上部类似的全球大气循环模式形成的，F. Michael Flasar在一篇相关的研究评述中写道。
报告：Evidence for a Polar Ethane Cloud on Titan, C. A. Griffith, et al.
研究评述：Titan's Polar Weather, F. M. Flasar
云层能推迟变暖吗？
根据一个可能的地球工程(geoengineering)战略的新模型，在地球上制造更多的云层覆盖也许能抵消全球变暖，从而给降低化石燃料的依赖提供更多的时间。Tom Wigley探索了用一种地球工程方法来减轻大气层二氧化碳过多所带来的破坏性影响，这个方法是将硫酸盐气溶胶前导物注入平流层，所产生的气溶胶可能增加云层覆盖。云层则可以将太阳光更多地反射回太空，从而降低大气二氧化碳浓度高所造成的变暖效应。Wigley用1991年6月皮纳图博火山爆发后该山上增加了的云层作为起点，来计算不同的可能性。他说，该火山爆发引起了短期的变冷，但是对气候系统没有产生没有大的影响。
科学特快报告：A Combined Mitigation/Geoengineering Approach to Climate Stabilization, T. M. L. Wigley
Contents
This Week in Science
Editor summaries of this week's papers.
Science 15 September 2006: 1537.
|Full Text »
Editorial:
Animal Activism: Out of Control
Donald Kennedy
Science 15 September 2006: 1541.
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Editors' Choice
Highlights of the recent literature.
Science 15 September 2006: 1542.
|Full Text »
NetWatch
Best of the Web in science.
Science 15 September 2006: 1547.
|Full Text »
Science Podcast
Science 15 September 2006: 1647.
Summary »|
NEW PRODUCTS
Science 15 September 2006: 1647.
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News of the Week
NONPROLIFERATION: Endgame for the U.S.-Russian Nuclear Cities Program
Richard Stone and Eli Kintisch
Science 15 September 2006: 1550.
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ARCHAEOLOGY: Claim of Oldest New World Writing Excites Archaeologists
Andrew Lawler
Science 15 September 2006: 1551.
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ASTROPHYSICS: Space Mission to Shine a Light on Solar Flares
Dennis Normile
Science 15 September 2006: 1553.
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INFECTIOUS DISEASE: Extensively Drug-Resistant TB Gets Foothold in South Africa
Jon Cohen
Science 15 September 2006: 1554.
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SCIENTIFIC COMMUNITY: Campaign Heats Up for WHO Director-General
Gretchen Vogel
Science 15 September 2006: 1554.
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INFLUENZA: Ground the Planes During a Flu Pandemic? Studies Disagree
Martin Enserink
Science 15 September 2006: 1555.
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GENOMICS: Poplar Tree Sequence Yields Genome Double Take
Erik Stokstad
Science 15 September 2006: 1556.
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ASTROPHYSICS: Pulsars' Gyrations Confirm Einstein's Theory
Adrian Cho
Science 15 September 2006: 1556-1557.
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PALEOANTHROPOLOGY: Mild Climate, Lack of Moderns Let Last Neandertals Linger in Gibraltar
Michael Balter
Science 15 September 2006: 1557.
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GENOMICS: Microarray Data Reproduced, But Some Concerns Remain
Jennifer Couzin
Science 15 September 2006: 1559.
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U.S. GRADUATE EDUCATION: Foreign Enrollment Rebounds After 3-Year Slump
Yudhijit Bhattacharjee
Science 15 September 2006: 1559.
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ScienceScope
Science 15 September 2006: 1553.
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Random Samples
Science 15 September 2006: 1549.
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Newsmakers
Science 15 September 2006: 1569.
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News Focus
GEOCHEMISTRY: Radiocarbon Dating's Final Frontier
Michael Balter
Science 15 September 2006: 1560-1563.
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CELL BIOLOGY: A Stressful Situation
Jean Marx
Science 15 September 2006: 1564-1566.
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INVASIVE SPECIES: The Galapagos Islands Kiss Their Goat Problem Goodbye
Jerry Guo
Science 15 September 2006: 1567.
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Letters
This Week's Letters
Science 15 September 2006: 1571.
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Cuts in Homeland Security Research
Francis Busta, Neville Clarke, Lynn R. Goldman, Charles Haas, Gabor Kelen, Gary Lafree, Joan Rose, and Detlof von Winterfeldt
Science 15 September 2006: 1571.
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Public Access Success at PubMed
David C. Beebe
Science 15 September 2006: 1571-1572.
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Support for the NIH Public Access Policy
Michael A. Rogawski and Peter Suber
Science 15 September 2006: 1572.
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Ongoing Controversy over Debye's WWII Role
The Executive Board of Utrecht University; and Martin Enserink
Science 15 September 2006: 1572-1573.
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Bias About Climate Change
Larry Neal
Science 15 September 2006: 1573.
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Books et al.
SOCIOLOGY: Through Art to Association in Japanese Politics
Christena Turner
Science 15 September 2006: 1575-1576.
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POLITICAL SCIENCE: Determinants of Democratization
Romain Wacziarg
Science 15 September 2006: 1576-1577.
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Books Received
Science 15 September 2006: 1577.
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Policy Forum
SOCIAL SCIENCE: Death in Darfur
John Hagan and Alberto Palloni
Science 15 September 2006: 1578-1579.
Summary »| Full Text »| PDF »| Supporting Online Material »|
Perspectives
CELL BIOLOGY: Enhanced: A Metabolic Push to Proliferate
Dawn L. Brasaemle
Science 15 September 2006: 1581-1582.
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PLANETARY SCIENCE: Titan's Polar Weather
F. M. Flasar
Science 15 September 2006: 1582-1583.
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MICROBIOLOGY: Mycobacteria's Export Strategy
Bérengère Ize and Tracy Palmer
Science 15 September 2006: 1583-1584.
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CHEMISTRY: The Organic Approach to Asymmetric Catalysis
Benjamin List and Jung Woon Yang
Science 15 September 2006: 1584-1586.
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STRUCTURAL BIOLOGY: Dynamic Visions of Enzymatic Reactions
Michele Vendruscolo and Christopher M. Dobson
Science 15 September 2006: 1586-1587.
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PHYSICS: Detecting and Controlling Electron Correlations
Markus Büttiker
Science 15 September 2006: 1587-1588.
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Review
Vesicle Formation at the Plasma Membrane and Trans-Golgi Network: The Same but Different
Mark A. McNiven and Heather M. Thompson
Science 15 September 2006: 1591-1594.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Brevia
Near-Field Microscopy Through a SiC Superlens
Thomas Taubner, Dmitriy Korobkin, Yaroslav Urzhumov, Gennady Shvets, and Rainer Hillenbrand
Science 15 September 2006: 1595.
Combining near-field optical microscopy with superlensing allows imaging of the internal structure of manmade or biological objects at a subwavelength scale.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Research Articles
The Genome of Black Cottonwood, Populus trichocarpa (Torr. & Gray)
G. A. Tuskan, S. DiFazio, S. Jansson, J. Bohlmann, I. Grigoriev, U. Hellsten, N. Putnam, S. Ralph, S. Rombauts, A. Salamov, J. Schein, L. Sterck, A. Aerts, R. R. Bhalerao, R. P. Bhalerao, D. Blaudez, W. Boerjan, A. Brun, A. Brunner, V. Busov, M. Campbell, J. Carlson, M. Chalot, J. Chapman, G.-L. Chen, D. Cooper, P. M. Coutinho, J. Couturier, S. Covert, Q. Cronk, R. Cunningham, J. Davis, S. Degroeve, A. Déjardin, C. dePamphilis, J. Detter, B. Dirks, I. Dubchak, S. Duplessis, J. Ehlting, B. Ellis, K. Gendler, D. Goodstein, M. Gribskov, J. Grimwood, A. Groover, L. Gunter, B. Hamberger, B. Heinze, Y. Helariutta, B. Henrissat, D. Holligan, R. Holt, W. Huang, N. Islam-Faridi, S. Jones, M. Jones-Rhoades, R. Jorgensen, C. Joshi, J. Kangasjärvi, J. Karlsson, C. Kelleher, R. Kirkpatrick, M. Kirst, A. Kohler, U. Kalluri, F. Larimer, J. Leebens-Mack, J.-C. Leplé, P. Locascio, Y. Lou, S. Lucas, F. Martin, B. Montanini, C. Napoli, D. R. Nelson, C. Nelson, K. Nieminen, O. Nilsson, V. Pereda, G. Peter, R. Philippe, G. Pilate, A. Poliakov, J. Razumovskaya, P. Richardson, C. Rinaldi, K. Ritland, P. Rouzé, D. Ryaboy, J. Schmutz, J. Schrader, B. Segerman, H. Shin, A. Siddiqui, F. Sterky, A. Terry, C.-J. Tsai, E. Uberbacher, P. Unneberg, J. Vahala, K. Wall, S. Wessler, G. Yang, T. Yin, C. Douglas, M. Marra, G. Sandberg, Y. Van de Peer, and D. Rokhsar
Science 15 September 2006: 1596-1604.
The poplar genome was duplicated 60 to 65 million years ago, marking the emergence of this tree family, but overall has evolved more slowly than that of Arabidopsis.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Opposing Activities Protect Against Age-Onset Proteotoxicity
Ehud Cohen, Jan Bieschke, Rhonda M. Perciavalle, Jeffery W. Kelly, and Andrew Dillin
Science 15 September 2006: 1604-1610.
Published online 10 August 2006 [DOI: 10.1126/science.1124646] (in Science Express Research Articles)
The insulin/insulin-like receptor pathway can detoxify protein aggregates in worms engineered to express excess protein in their muscles, perhaps partly explaining its role in aging.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Oldest Writing in the New World
Ma. del Carmen Rodríguez Martínez, Ponciano Ortíz Ceballos, Michael D. Coe, Richard A. Diehl, Stephen D. Houston, Karl A. Taube, and Alfredo Delgado Calderón
Science 15 September 2006: 1610-1614.
A stone block containing unknown symbols and dating to the first millennium B.C.E. has been discovered in Veracruz, Mexico, a center of the Olmec civilization.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Reports
Probing Nanoscale Ferroelectricity by Ultraviolet Raman Spectroscopy
D. A. Tenne, A. Bruchhausen, N. D. Lanzillotti-Kimura, A. Fainstein, R. S. Katiyar, A. Cantarero, A. Soukiassian, V. Vaithyanathan, J. H. Haeni, W. Tian, D. G. Schlom, K. J. Choi, D. M. Kim, C. B. Eom, H. P. Sun, X. Q. Pan, Y. L. Li, L. Q. Chen, Q. X. Jia, S. M. Nakhmanson, K. M. Rabe, and X. X. Xi
Science 15 September 2006: 1614-1616.
Ultraviolet Raman spectroscopy reveals the temperature at which thin films become ferroelectric and can guide the addition of layers to tune this transition.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Near-Threshold Inelastic Collisions Using Molecular Beams with a Tunable Velocity
Joop J. Gilijamse, Steven Hoekstra, Sebastiaan Y. T. van de Meerakker, Gerrit C. Groenenboom, and Gerard Meijer
Science 15 September 2006: 1617-1620.
Slowing down OH radicals to specific, precise velocities allows detailed study of the quantum mechanical effects on their low-energy collisions with noble gas atoms.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Evidence for a Polar Ethane Cloud on Titan
C. A. Griffith, P. Penteado, P. Rannou, R. Brown, V. Boudon, K. H. Baines, R. Clark, P. Drossart, B. Buratti, P. Nicholson, C. P. McKay, A. Coustenis, A. Negrao, and R. Jaumann
Science 15 September 2006: 1620-1622.
Cassini has detected a polar cloud on Titan that may trap ethane produced in its atmosphere, explaining the lack of liquid ethane on the surface.
Abstract »| Full Text »| PDF »|
Early Reactivation of European Rivers During the Last Deglaciation
Guillemette Ménot, Edouard Bard, Frauke Rostek, Johan W. H. Weijers, Ellen C. Hopmans, Stefan Schouten, and Jaap S. Sinninghe Damsté
Science 15 September 2006: 1623-1625.
The flow of the huge river system that drained Europe through what is now the English Channel increased abruptly and dramatically during the last deglaciation.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
High Gamma Power Is Phase-Locked to Theta Oscillations in Human Neocortex
R. T. Canolty, E. Edwards, S. S. Dalal, M. Soltani, S. S. Nagarajan, H. E. Kirsch, M. S. Berger, N. M. Barbaro, and R. T. Knight
Science 15 September 2006: 1626-1628.
A characteristic, low-frequency brain wave modulates ultrahigh-frequency oscillations, thereby allowing communication among areas of the cortex that support behavior.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Caveolin-1 Is Essential for Liver Regeneration
Manuel A. Fernández, Cecilia Albor, Mercedes Ingelmo-Torres, Susan J. Nixon, Charles Ferguson, Teymuras Kurzchalia, Francesc Tebar, Carlos Enrich, Robert G. Parton, and Albert Pol
Science 15 September 2006: 1628-1632.
Mice lacking a protein that helps cells internalize other proteins and signaling molecules seem to be normal, but their livers cannot regenerate after being damaged.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
C-Terminal Signal Sequence Promotes Virulence Factor Secretion in Mycobacterium tuberculosis
Patricia A. DiGiuseppe Champion, Sarah A. Stanley, Matthew M. Champion, Eric J. Brown, and Jeffery S. Cox
Science 15 September 2006: 1632-1636.
The pathogen that causes tuberculosis tags proteins for processing by its unusual secretory system with an unstructured carboxyl terminal sequence.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
An Alternative Bactericidal Mechanism of Action for Lantibiotic Peptides That Target Lipid II
Hester E. Hasper, Naomi E. Kramer, James L. Smith, J. D. Hillman, Cherian Zachariah, Oscar P. Kuipers, Ben de Kruijff, and Eefjan Breukink
Science 15 September 2006: 1636-1637.
A new class of antibiotics has an unusual target–a molecule needed for bacterial cell wall synthesis-and may be especially useful against resistant microbes.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
The Dynamic Energy Landscape of Dihydrofolate Reductase Catalysis
David D. Boehr, Dan McElheny, H. Jane Dyson, and Peter E. Wright
Science 15 September 2006: 1638-1642.
An enzyme progresses through its reaction cycle by fluctuating between the ground state and the higher-energy states of each kinetic intermediate.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Imaging Intracellular Fluorescent Proteins at Nanometer Resolution
Eric Betzig, George H. Patterson, Rachid Sougrat, O. Wolf Lindwasser, Scott Olenych, Juan S. Bonifacino, Michael W. Davidson, Jennifer Lippincott-Schwartz, and Harald F. Hess
Science 15 September 2006: 1642-1645.
Published online 10 August 2006 [DOI: 10.1126/science.1127344] (in Science Express Reports)
Proteins of interest can be labeled with fluorescent tags and located by photoactivated localization microscopy (PALM) in thin sections and fixed cells at near-molecular resolution.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Technical Comments
Comment on "Large-Scale Sequence Analysis of Avian Influenza Isolates"
Edward C. Holmes, David J. Lipman, Dmitriy Zamarin, and Jonathan W. Yewdell
Science 15 September 2006: 1573.
Abstract »| Full Text »| PDF »|
Response to Comment on "Large-Scale Sequence Analysis of Avian Influenza Isolates"
John C. Obenauer, Yiping Fan, and Clayton W. Naeve
Science 15 September 2006: 1573.
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