2006年1月27日 美国《科学》周刊311卷 第5760期禽流感病毒数据增加了一倍
一项新研究使公共数据库中的禽流感基因信息增加了一倍，研究还揭示了一个新的基因模体(motif)，这可能是某些爆发流感病毒(包括正在亚洲和欧洲爆发的H5N1禽流感)毒性的关键。John Obenauer和同事分析了2196个禽流感基因以及169个采集的不同野生鸟类样品的完整基因组。他们在禽流感病毒NS 1蛋白上发现了一个特殊的模体，该模体可能会使病毒与人类宿主的某些蛋白结合，破坏这些蛋白的活性。研究人员说，高死亡率的H5N1病毒的NS 1蛋白上都有一个"禽"模体，而1957年和1969年曾爆发过的低死亡率两种病毒的NS 1蛋白上有一个人类"模体，这个模体看起来与宿主蛋白相互作用的能力较差。Obenauer和同事还用了一个他们称为"蛋白分型(proteotyping)"的技术在禽流感蛋白中寻找独特的氨基酸差别，来确定病毒的变化，这些变化可能被跟踪病毒基因进化的传统家系树方法漏掉。研究人员说，这个技术也许"对在感染过程中确定流感病毒蛋白相互作用上有用"。
科学特快报告：Large-Scale Sequence Analysis of Avian Influenza Isolates, John C. Obenauer, et al.
鹿肌肉中的朊毒体
新研究指出，感染了慢性消耗病(CWD)鹿的腿部肌肉中有传染性朊毒体。朊毒体是哺乳动物的能传染的蛋白质介质，能引起中枢神经系统致命的神经退化性疾病。慢性消耗病是一种传染的朊毒体病，主要感染北美的鹿和麋鹿。研究人员将患有CWD骡鹿的腿部肌肉和大脑的提取物注射给易患CWD的转基因小鼠的大脑中。提取物在小鼠身上引发了进展性神经系统功能障碍。大脑提取物比肌肉提取物的作用来得快，意味着患有CWD鹿的大脑中比腿部肌肉中的感染性朊毒体的量高。新研究说，处理或食用感染了CWD 鹿的人有感染朊毒体的风险。作者写道，虽然还不知道CWD是否能传染给人，但是人们已经知道，接触来自患有疯牛病的牛朊毒体能引起人类的变异型克雅氏病。作者还指出，对被疯牛病感染的牛骨骼肌肉的类似分析没有在其中发现大量的朊毒体感染性。
科学特快报告：Large-Scale Sequence Analysis of Avian Influenza Isolates, Rachel C. Angers, et al.
用来病毒跟踪美洲豹种群
研究人员用一种病毒跟踪了美洲豹种群在北美西部的恢复，美洲豹曾几乎被人类捕杀光。这项研究为用感染较慢进化哺乳动物的较快进化病原体来跟踪一个动物种群的变化提供了一个具体实例，动物保护主义者和科学家对这个想法的讨论已有一段时间，但是此前还没有碰到检验这个想法的一组理想条件。Roman Biek和同事用了一个猫科免疫缺陷病毒作为"标签"来确定在停止捕猎美洲豹后，美洲豹种群是在何地何时开始恢复的。他们从美国蒙大拿州和怀俄明州以及加拿大不列颠哥伦比亚省和艾伯塔省的352只美洲豹身上采样了这种病毒并对其做了基因分析(这个病毒似乎并不使美洲豹生病)。分析的结果显示，病毒的8个主要株是在最近几十年才开始分离进化的，大概与几个范围大大缩小了的、地理隔离的美洲豹种群相对应。在这样短的时间内美洲豹的基因进化发生得很慢，所以看不到其中的变化，使得进化快的病毒成为监测被其感染的美洲豹宿主的较快种群变化的理想工具。
报告：A Virus Reveals Population Structure and Recent Demographic History of Its Carnivore Host, Roman Biek, Alexei J. Drummond, and Mary Poss
为什么喊不聋自己的耳朵
为什么我们为自己喜爱的运动队助威而大声喊叫时，不会使自己变聋？这是因为动物的大脑有一个保护不受自身噪声破坏的方法，现在来自唱歌蟋蟀的新证据揭示了这个保护通道的一个分子基础。大脑的运动神经元能发给感觉神经元一个信号让其在我们产生刺激(比如大喊)的同时"不理"所产生的感觉刺激。现在James Poulet和Berthold Hedwig在唱歌蟋蟀身上找到了这个过程中的神经中介。他们发现了一个传递这个"不理"信号的中间神经元，并发现这个中间神经元的活动是由蟋蟀制造歌声的神经元所驱动的。这个中间神经元帮助蟋蟀将自己的歌声与其它蟋蟀的歌声区别开。有趣的是，蟋蟀飞的时候会关闭这个中间神经元，所以没有任何东西来干预它们听到饥饿蝙蝠回声定位叫声的能力。
报告：The Cellular Basis of a Corollary Discharge, James F. A. Poulet and Berthold Hedwig
乙醇的能效比过去认为的要高
本期一篇报告指出，占美国运输燃料混合2%的用玉米制造的乙醇的能效，比过去研究提出的要高。Alexander Farrell和同事仔细分析了六项过去的研究，其中有两项的结论是生产乙醇所需的能量比乙醇所能提供的能量高。Farrell发现这两项研究中存在几个问题，包括它们用的是过时的乙醇生产方法数据，也没有将乙醇副产品的能效考虑进来。作者的新估算表明，基于玉米的乙醇能使每加仑燃料中的石油产品降低95%，但是只能使释放的温室气体减少13%。Farrell和同事说，改进的农业生产方式以及用其它植物来生产生产乙醇将能进一步提高乙醇的环境优越性。
在另一篇综述中，Arthur Ragauskas和同时说，不断减少的化石燃料储存、全球变暖、以及汽油涨价所带来的经济苦恼等都指出未来使用生物燃料的必要性。本文作者描述了生物燃料生产的不远将来的前景：研究人员正在建设更好的生物提炼厂，用基因组工具来增加燃料作物的产量，应用化学技术将生物燃料原料降解和转换成燃料与具有商业价值的塑料和润滑剂等副产品。作者说，生物信息学能被用来发现再利用生物燃料废物的途径。
报告：Ethanol Can Contribute to Energy and Environmental Goals, Alexander E. Farrell, et al.
综述：The Path Forward for Biofuels and Biomaterials, Arthur J. Ragauskas, et al.
冰冻制造高强度陶瓷
Sylvain Deville和同事在研制更强、更硬、更轻的材料中发现，使水和陶瓷粉的混合液有控制地冻冰，能仿制出像软体动物壳那样的超强珍珠质结构。水结冰时能形成以不同速度、朝不同方向生长的六角板。如果水中有杂质，它们会被困陷在水和冰的界面。研究人员用冰冻的方法将含有高浓度陶瓷粉的水混合体制造成多孔材料。然后用另一种材料填充到这种多孔材料中，来制造超强、超轻的组合材料，该组合材料具有比传统陶瓷材料更好的机械性质。材料科学家和工程师John Halloran在相关的研究评述中指出，这种组合材料有广泛的工程应用。这项研究结合了现有的常用处理手段，比如陶瓷工业的粉末加工，金属铸造和食品冷冻工业中的控制固化，以及化学、食品和咖啡工业中用的冷冻干燥。
报告：Freezing as a Path to Build Complex Composites, Sylvain Deville, Eduardo Saiz, Ravi K. Nalla, and Antoni P. Tomsia
研究评述：Making Better Ceramic Composites with Ice, Rebecca Heald
Contents
For all checked items
This Week in Science
Editor summaries of this week's papers.
Science 27 January 2006: 432.
|Full Text »
Editorial:
Getting Serious About Biofuels
Steven E. Koonin
Science 27 January 2006: 435.
Summary »| PDF »|
Editors' Choice
Highlights of the recent literature.
Science 27 January 2006: 437.
|Full Text »
NetWatch
Best of the Web in science.
Science 27 January 2006: 445.
|Full Text »
NEW PRODUCTS
Science 27 January 2006: 542.
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News of the Week
SCIENTIFIC MISCONDUCT: Fraud Upends Oral Cancer Field, Casting Doubt on Prevention Trial
Jennifer Couzin and Michael Schirber
Science 27 January 2006: 448-449.
Summary »| Full Text »| PDF »|
PROFESSIONAL PRACTICE: Scientists Keep Some Data to Themselves
Constance Holden
Science 27 January 2006: 448.
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GRADUATE TRAINING: U.S. Beckons Foreigners With Science Fulbrights
Jeffrey Mervis
Science 27 January 2006: 449.
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QUANTUM PHYSICS: Measurement Schemes Let Physicists Tiptoe Through the Quanta
Adrian Cho
Science 27 January 2006: 451.
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ECOLOGY: Rare Tree Species Thrive in Local Neighborhoods
Elizabeth Pennisi
Science 27 January 2006: 452-453.
Summary »| Full Text »| PDF »|
CHEMISTRY: Walk on the Wild Side Yields Supersensitive Chemical Measurements
Robert F. Service
Science 27 January 2006: 452.
Summary »| Full Text »| PDF »|
EXTRASOLAR PLANETS: I Spy … a Cold, Little Planet
Richard A. Kerr
Science 27 January 2006: 453.
Summary »| Full Text »| PDF »|
ILLEGAL DRUGS: U.K. Backs Off Reclassifying Cannabis as a Dangerous Drug
Eliot Marshall
Science 27 January 2006: 455.
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JAPAN-CHINA DISPUTE: Researchers Caught Between Atoll and a Hard Place
Dennis Normile
Science 27 January 2006: 455.
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AVIAN INFLUENZA: Donors Draw Plans to Disburse $2 Billion War Chest for Bird Flu
Dennis Normile and Gong Yidong
Science 27 January 2006: 456-457.
Summary »| Full Text »| PDF »|
GENETICS: Biobank Ties Cancer Genes to Rare Developmental Syndrome
Gretchen Vogel
Science 27 January 2006: 456.
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VIROLOGY: Genomic Analysis Hints at H5N1 Pathogenicity
Dennis Normile
Science 27 January 2006: 457.
Summary »| Full Text »| PDF »|
ScienceScope
Science 27 January 2006: 451.
|Full Text »
Random Samples
Science 27 January 2006: 447.
|Full Text »
Newsmakers
Science 27 January 2006: 467.
|Full Text »
News Focus
MENTAL HEALTH IN DEVELOPING COUNTRIES: The Unseen: Mental Illness's Global Toll
Greg Miller
Science 27 January 2006: 458-461.
Summary »| Full Text »| PDF »|
MENTAL HEALTH IN DEVELOPING COUNTRIES: Mapping Mental Illness: An Uncertain Topography
Greg Miller
Science 27 January 2006: 460-461.
Summary »| Full Text »| PDF »|
MENTAL HEALTH IN DEVELOPING COUNTRIES: China: Healing the Metaphorical Heart
Greg Miller
Science 27 January 2006: 462-463.
Summary »| Full Text »| PDF »|
MENTAL HEALTH IN DEVELOPING COUNTRIES: A Spoonful of Medicine--and a Steady Diet of Normality
Greg Miller
Science 27 January 2006: 464-465.
Summary »| Full Text »| PDF »|
Letters
This Week's Letters
Science 27 January 2006: 468.
Summary »| PDF »|
Where Next for Genome Sequencing?
Peter Raven, Claude Fauquet, M. S. Swaminathan, Norman Borlaug, and Cristián Samper
Science 27 January 2006: 468.
Full Text »| PDF »|
Thinking About NASA's Future
Michael Barratt;, Andrea Hanson;, and Jeffrey Plescia
Science 27 January 2006: 469.
Full Text »| PDF »|
Avoiding Climate Change
James E. Hansen
Science 27 January 2006: 469-470.
Full Text »| PDF »|
Corrections and Clarifications
Science 27 January 2006: 470.
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Books et al.
SCIENCE AND RELIGION: Believing in Belief
Michael Shermer
Science 27 January 2006: 471-472.
Summary »| Full Text »| PDF »|
CLIMATE: Early and Profound Human Impact?
James White
Science 27 January 2006: 472.
Summary »| Full Text »| PDF »|
Books Received
Science 27 January 2006: 472.
Summary »|
Education Forum
PROFESSIONAL SKILLS: Enhanced: The Merits of Training Mentors
Christine Pfund, Christine Maidl Pribbenow, Janet Branchaw, Sarah Miller Lauffer, and Jo Handelsman
Science 27 January 2006: 473-474.
Summary »| Full Text »| PDF »| Supporting Online Material »|
Perspectives
BIOCHEMISTRY: Loop Grafting and the Origins of Enzyme Species
Dan S. Tawfik
Science 27 January 2006: 475-476.
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ATMOSPHERE: Climate Change and Human Evolution
Anna K. Behrensmeyer
Science 27 January 2006: 476-478.
Summary »| Full Text »| PDF »|
GEOCHEMISTRY: Rising Mountain Ranges
Michael A. Poage and C. Page Chamberlain
Science 27 January 2006: 478-479.
Summary »| Full Text »| PDF »|
MATERIALS SCIENCE: Making Better Ceramic Composites with Ice
John Halloran
Science 27 January 2006: 479-480.
Summary »| Full Text »| PDF »|
ECOLOGY: Staying Connected in a Turbulent World
Robert S. Steneck
Science 27 January 2006: 480-481.
Summary »| Full Text »| PDF »|
Association Affairs
AAAS News and Notes
Science 27 January 2006: 482.
Summary »| Full Text »| PDF »|
Review
The Path Forward for Biofuels and Biomaterials
Arthur J. Ragauskas, Charlotte K. Williams, Brian H. Davison, George Britovsek, John Cairney, Charles A. Eckert, William J. Frederick, Jr., Jason P. Hallett, David J. Leak, Charles L. Liotta, Jonathan R. Mielenz, Richard Murphy, Richard Templer, and Timothy Tschaplinski
Science 27 January 2006: 484-489.
Abstract »| Full Text »| PDF »|
Brevia
The Orbital Period of the Ultraluminous X-ray Source in M82
Philip Kaaret, Melanie G. Simet, and Cornelia C. Lang
Science 27 January 2006: 491.
Published online 5 January 2006 [DOI: 10.1126/science.1121067] (in Science Express Brevia)
Periodic brightening of luminous X-ray source may be due to gas supplied from a bloated star orbiting around a massive black hole.
Abstract »| Full Text »| PDF »|
Research Articles
Fermionic Superfluidity with Imbalanced Spin Populations
Martin W. Zwierlein, André Schirotzek, Christian H. Schunck, and Wolfgang Ketterle
Science 27 January 2006: 492-496.
Published online 22 December 2005 [DOI: 10.1126/science.1122318] (in Science Express Research Articles)
Cold clouds of atoms with unequal populations of atomic spins can maintain a surprisingly robust superfluid state, which requires paired spins.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Community Genomics Among Stratified Microbial Assemblages in the Ocean's Interior
Edward F. DeLong, Christina M. Preston, Tracy Mincer, Virginia Rich, Steven J. Hallam, Niels-Ulrik Frigaard, Asuncion Martinez, Matthew B. Sullivan, Robert Edwards, Beltran Rodriguez Brito, Sallie W. Chisholm, and David M. Karl
Science 27 January 2006: 496-503.
Community genomic analysis indicates that the microbes near the surface of the Northern Pacific are mobile and photosynthetic, while those below 200 meters have pili and synthesize polysaccharides and antibiotics.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Reports
Pairing and Phase Separation in a Polarized Fermi Gas
Guthrie B. Partridge, Wenhui Li, Ramsey I. Kamar, Yean-an Liao, and Randall G. Hulet
Science 27 January 2006: 503-505.
Published online 22 December 2005 [DOI: 10.1126/science.1122876] (in Science Express Reports)
Cold clouds of atoms with unequal populations of atomic spins can maintain a surprisingly robust superfluid state, which requires paired spins.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Ethanol Can Contribute to Energy and Environmental Goals
Alexander E. Farrell, Richard J. Plevin, Brian T. Turner, Andrew D. Jones, Michael O'Hare, and Daniel M. Kammen
Science 27 January 2006: 506-508.
A systems analysis shows that, contrary to some studies, biofuel ethanol can yield more energy than is required for its synthesis; nevertheless, better production technologies are needed.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Optical Detection of DNA Conformational Polymorphism on Single-Walled Carbon Nanotubes
Daniel A. Heller, Esther S. Jeng, Tsun-Kwan Yeung, Brittany M. Martinez, Anthonie E. Moll, Joseph B. Gastala, and Michael S. Strano
Science 27 January 2006: 508-511.
Metal ions in solution can change the way DNA wraps around a singlewalled nanotube and affect the tube's fluorescence, providing a sensitive detector.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Rapid Uplift of the Altiplano Revealed Through 13C-18O Bonds in Paleosol Carbonates
Prosenjit Ghosh, Carmala N. Garzione, and John M. Eiler
Science 27 January 2006: 511-515.
A paleothermometer based on binding strength between rare C and O isotopes within carbonates shows that the Bolivian Altiplano rose rapidly about 8 million years ago.
Abstract »| Full Text »| PDF »|
Freezing as a Path to Build Complex Composites
Sylvain Deville, Eduardo Saiz, Ravi K. Nalla, and Antoni P. Tomsia
Science 27 January 2006: 515-518.
Ice is used to template colloidal particles into forming bone and nacre-like structures and then is easily removed, leaving a contaminant-free substrate for further reinforcement.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
The Cellular Basis of a Corollary Discharge
James F. A. Poulet and Berthold Hedwig
Science 27 January 2006: 518-522.
Crickets "know" when they hear their own song because the neural circuit for singing sends a corollary discharge to auditory neurons as well as to the motor circuit for singing.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Scaling of Connectivity in Marine Populations
R. K. Cowen, C. B. Paris, and A. Srinivasan
Science 27 January 2006: 522-527.
Published online 15 December 2005 [DOI: 10.1126/science.1122039] (in Science Express Reports)
Larvae of coastal fish in the Caribbean typically disperse only 10 to 100 kilometers, less than had been thought, yielding more isolated populations.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Nonrandom Processes Maintain Diversity in Tropical Forests
Christopher Wills, Kyle E. Harms, Richard Condit, David King, Jill Thompson, Fangliang He, Helene C. Muller-Landau, Peter Ashton, Elizabeth Losos, Liza Comita, Stephen Hubbell, James LaFrankie, Sarayudh Bunyavejchewin, H. S. Dattaraja, Stuart Davies, Shameema Esufali, Robin Foster, Nimal Gunatilleke, Savitri Gunatilleke, Pamela Hall, Akira Itoh, Robert John, Somboon Kiratiprayoon, Suzanne Loo de Lao, Marie Massa, Cheryl Nath, Md. Nur Supardi Noor, Abdul Rahman Kassim, Raman Sukumar, Hebbalalu Satyanarayana Suresh, I-Fang Sun, Sylvester Tan, Takuo Yamakura, and Jess Zimmerman
Science 27 January 2006: 527-531.
Long-term census of trees in tropical forest plots shows that rare species survive preferentially, leading to more species diversity as forests age.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
An Architectural Framework That May Lie at the Core of the Postsynaptic Density
Marisa K. Baron, Tobias M. Boeckers, Bianca Vaida, Salem Faham, Mari Gingery, Michael R. Sawaya, Danielle Salyer, Eckart D. Gundelfinger, and James U. Bowie
Science 27 January 2006: 531-535.
A scaffolding protein, assisted by bound Zn2+, can assemble into large sheets and may form a platform for the construction of the postsynaptic density.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Design and Evolution of New Catalytic Activity with an Existing Protein Scaffold
Hee-Sung Park, Sung-Hun Nam, Jin Kak Lee, Chang No Yoon, Bengt Mannervik, Stephen J. Benkovic, and Hak-Sung Kim
Science 27 January 2006: 535-538.
A process that mimics natural protein evolution converts an enzyme in the metallohydrolase superfamily into a new family member with a different catalytic function.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
A Virus Reveals Population Structure and Recent Demographic History of Its Carnivore Host
Roman Biek, Alexei J. Drummond, and Mary Poss
Science 27 January 2006: 538-541.
An innocuous virus carried by cats shows that recent cougar populations result from the expansion and merging of small isolated populations that had been reduced by hunting.
Abstract »| Full Text »| PDF »| Supporting Online Material »|
Technical Comments
Comment on "Reconstructing the Origin of Andaman Islanders"
Malliya gounder Palanichamy, Suraksha Agrawal, Yong-Gang Yao, Qing-Peng Kong, Chang Sun, Faisal Khan, Tapas Kumar Chaudhuri, and Ya-Ping Zhang
Science 27 January 2006: 470.
Abstract »| Full Text »| PDF »|
Response to Comment on "Reconstructing the Origin of Andaman Islanders"
Kumarasamy Thangaraj, Gyaneshwer Chaubey, Toomas Kivisild, Alla G. Reddy, Vijay Kumar Singh, Avinash A. Rasalkar, and Lalji Singh
Science 27 January 2006: 470.
Abstract »| Full Text »| PDF »|
