Volume 433 Number 7025 pp443-556封面故事：成群动物中的信息传递
处于运动中的成群动物，包括鱼、有蹄动物、鸟类和蜂群，似乎能在没有信号传递机制以及群体成员不能判断谁获得了信息、谁未获得信息时做复杂决定。一项数值模拟研究，让我们看到了这些动物群体为什么能做出准确的、一致的决定，以及为什么群体越大、引导群体所需的获得信息的个体所占比例越小。比例非常小的一组获得信息的个体就足以取得近乎最大的准确性。该结果对于我们了解群体中信息传递的演化有参考价值，也为引导群体机器人提出了一个新的设计思路。封面照片（由Phillip Colla Natural History Photography提供，网址 ）所示为成群的茄克竹荚鱼。
新型伊斯兰女权运动
传统观念使得巴基斯坦妇女几乎不可能从事科学研究。但事情正在开始发生变化。一种新型伊斯兰女权运动正在兴起，在这项运动中，妇女要求获得伊斯兰教给予她们的权利，尽管如Ehsan Massood所报道的那样，这将是一场艰苦的斗争。
纸一样的共轴碳纳米管
双壁碳纳米管（DWNT）由两个同心的石墨烯圆柱体组成，是单壁和多壁碳纳米管之间的一个中间结构。一种共轴结构可能是用在纳米复合物和电子装置中的理想结构。以前，一直不可能以一种纯晶体形式获得DWNT，但现在Endo等人报告，他们研制成一种纸一样的材料，由呈六边形堆积的干净的、共轴的碳纳米管束组成。有了这种“巴克纸”，就有可能确定DWNT的物理性质；据预测，对某些应用，它们的性质优于单壁和多壁碳纳米管。
信使RNA的激发
一个活细胞一次只表达其DNA内的一小部分基因，尤其是在真核细胞中，基因组中很多基因都是没有用的，并不会变成信使RNA。但即使对合成的信使RNA，并不总会立即被表达为某种蛋白质。 它们会被保留在细胞质中，直到需要的时候，这时它们由于“起始因子” eIF4E在其5' 端结合到修改后的鸟苷帽上而受到激发。Joel Richter和Nahum Sonenberg对有关这一体系的最新研究进行了综述。该体系控制发育、细胞生长和肿瘤形成等多种不同过程。
形态演化的分子基础
基因调节所发生的变化被认为是形态演化的核心，但这种变化的分子基础仍然不是很清楚。现在，对1500万年前出现在Drosophila biarmipes种系中的一个翼斑的遗传所做的分析，反映了这一雄性色斑图案（在配偶选择中很可能是一个因素）是怎样通过Engrailed蛋白的结合点的出现来演化的。Engrailed蛋白是深度保留的转录因子，涉及节肢动物形体的形成。这样便形成了一个跨越演化时间的变化“处方”：调节DNA序列或cis-调节成分的随机突变生成潜在的结合点。如果一个新的结合点被一个现有转录因子识别出来，基因表达的变化就可能会出现，而且如果条件允许，新的形态特征就会出现。
“丢失的”重子找到了
根据当前的宇宙模型，重子（正常的普通物质中的基本粒子）占宇宙中总物质密度的约5%。在高红移所做的观测支持这种预测，但在时空上离地球更近的地方，只探测到以上数字一半的重子。这促使科学家去寻找丢失的“正常”物质（而不是“暗”物质）。Nicastro等人报告了一个以前不知道的重子源的发现，存在于星际介质的一个温-热相中，它们的质量与“丢失的”重子的质量是一致的。
向天空中发射的无线电信号
位于阿拉斯加Gakona附近的HAARP天文台上的强大的射电发射机阵列，是设计用来向天空中发射狭窄的一束强大的无线电信号的。对这种干预的反应显示了电离层的详细化学和物理性质。2004年3月完成的这样一个实验有一个出乎意料的结果，诱导产生了亮到足以能被裸眼看成是小斑点的人工发射的光。这不是发生在安静的电离层，而是在一个活泼脉动的极光中，其所代表的特征比以前任何时候所观测到的都要小得多、亮得多。
甲基氯仿溶剂的排放量到底有多大？
甲基氯仿溶剂的使用正在依据《蒙特利尔议定书》而被废除，这是因为它能破坏臭氧层。该物质在大气中的浓度正在下降，但一项最新研究在欧洲的排放问题上却得出了冲突的结果。现在，对该物质排放量的估计值在不到每年0.1Gg到超过每年20Gg之间，后一个数超过以前全球估计值的两倍。研究人员进行了一项新的研究，来根据来自爱尔兰Mace Head和瑞士Jungfraujoch的观测点的数据对这些排放量估计值进行评估，结果不支持最近得出的每年超过20Gg的过高排放量，但由于该研究所得出的排放量估计值对上个世纪90年代中期为每年60Gg、对2000-2003年这一时期为每年3.4Gg，所以它们也高于最新的、基于消费量的数字。本文作者猜测，如果他们的数字是正确的，那么一定存在没有被记录的甲基氯仿排放源，这说明企业对排放量的报告严重过低，《蒙特利尔议定书》的报告过程对消费量的报告也可能严重过低。
“星鼻鼹”的快速捕食能力
“猎物获利能力”指的是所获得的能量与处理一个猎物所花时间的比例，它是行为生态学的一个中心部分。多数猎物处理时间持续几分钟或几秒钟，但“星鼻鼹”却出类拔萃：它能在120毫秒内识别出并吃掉一个猎物。由于有这种本事，它已成为自然界最古老的动物之一，有星状的脸、奇怪的鼻子和一个非常适合速度的神经系统。这种演化旅程可由一种异常强大的“逃跑”速度选择来解释，后者是由最快吃食者越来越大的“猎物获利能力”引起的。“星鼻鼹”能借助它们的速度来利用（小型无脊椎动物的）大资源，后者对于其他动物来说实际上是浪费时间。
大肠杆菌的蛋白-蛋白相互作用网络
研究人员将有关大肠杆菌（E. coli）中原态蛋白-蛋白相互作用的蛋白组分析研究与蛋白质谱研究相结合，发现了一个相互作用网络，由对细菌生命非常重要的蛋白组成。该网络是高度保留的，能为了解核心细菌过程、演化限制因素的性质、以及合适的抗菌药物的新作用目标提供线索。
基因组中的半分子
要发现基因，需要有侦探的技能。现在，这种说法有了更多证据。超耐温寄生虫Nanoarchaeum equitans具有已知最小的基因组。它似乎太小了，研究人员发现，它竟然缺少蛋白生物合成所需的4个转移RNA（tRNA）。这种寄生虫的生存之谜已经揭开了：它是通过一分两半来做事的。一种新的计算方法显示，“丢失的”tRNA基因为基因组中的半分子。tRNA片段的结构显示了将这种半分子结合在一起的一种机制，该生物也含有这些tRNA的全长度活泼版本。分裂的tRNA基因可能是古老生物的标志（N. equitans古细菌家族的一个成员），或者说它们可能是在缩小基因组大小的过程中生成的。
Daumone的性质和身份
线虫C. elegans的dauer形式是其生命周期中的一个非衰老阶段，对于在如食物短缺这样的不利条件下是有益的。在线虫C. elegans中调节衰老和发育的天然的dauer诱导信息素（称之为“daumone”）的性质已被研究了很多年，但其精确的生化身份仍然不为人们所知。现在，Daumone已被纯化，并完全定性，而且正如所预测的那样，它是一种脂肪酸衍生物。天然和化学合成的daumone都同样诱导dauer幼虫的形成。这项工作有可能导致新型抗线虫药物的问世，对于衰老和肥胖的研究也有意义。
本期目录：
Editorials
Facing reality at NASA p443
The US space agency is facing a crisis that neither it nor its political stakeholders seem willing to tackle. Something big has to give, and it shouldn't be science.
doi: 10.1038/433443a
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Turf battles versus German excellence p443
Disputes between Germany's states and its federal government need not cripple the country's research priorities.
doi: 10.1038/433443b
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Top of pageNews
DNA is burning issue as Japan and Korea clash over kidnaps p445
Cremated remains fail to prove fate of Japanese girl abducted in 1977.
David Cyranoski
doi: 10.1038/433445a
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Publishers irritated by Google's digital library p446
Plan to digitize university library collections sparks copyright spat.
Declan Butler
doi: 10.1038/433446a
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University dispute puts Berlin science meetings in crisis p446
Future of Dahlem Conferences hangs in the balance as board contemplates resignation.
Alison Abbott
doi: 10.1038/433446b
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Lab relations sour as 'missing disk' charges are proved false p447
Los Alamos lab's computer disks didn't go missing - they never existed.
Geoff Brumfiel
doi: 10.1038/433447a
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Cancellation e-mail shakes recipients of outer-planet grants p447
NASA notice of grant cuts was just a 'miscommunication', agency says.
Tony Reichhardt
doi: 10.1038/433447b
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Political deadlock delays promised German research cash p448
2 billion euros and a 3% budget rise held "hostage", says funding president.
Quirin Schiermeier
doi: 10.1038/433448a
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Hopes rise as head named for troubled conservation centre p448
Graham Watkins named director of Charles Darwin Foundation in Galapagos.
Henry Nicholls
doi: 10.1038/433448b
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African network set to boost Earth sciences p449
Geophysicists aim to bolster local skills throughout Africa.
Rex Dalton
doi: 10.1038/433449a
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Reformation of bird-brain terminology takes off p449
New nomenclature reflects similarities between bird and mammal brains.
Jessica Ebert
doi: 10.1038/433449b
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news in brief p450
doi: 10.1038/433450a
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Top of pageNews Features
Women at work p452
Pakistan's traditional ways have blocked many women's careers in science. But, as Ehsan Masood discovers, women are now fighting for their rights, both in life and in research.
doi: 10.1038/433452a
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Skeleton keys p454
Mexican scientists now have the skills and technology to study their backlog of ancient bones. As this treasure trove begins to yield its secrets, Rex Dalton finds local scientists hoping to unravel the mysteries of the earliest settlers of America.
doi: 10.1038/433454a
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Top of pageCorrespondence
Rebuilding fisheries will add to Asia's problems p457
Overfishing has already caused depletion and conflict. Instead, train people for new jobs.
Daniel Pauly
doi: 10.1038/433457a
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Need for a risk-informed tsunami alert system p457
Gordon Woo and Willy Aspinall
doi: 10.1038/433457b
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Top of pageBooks and Arts
Part of the culture p459
Magazines and journals reveal how the Victorians viewed science.
doi: 10.1038/433459a
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Fermi's legacy p460
doi: 10.1038/433460a
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Science in culture p461
It's still the periodic table — but with a twist.
Martin Kemp
doi: 10.1038/433461a
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Life and death in Sumatra p462
doi: 10.1038/433462a
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Top of pagePhysics detective
Schr?dinger's mousetrap p463
Part 3: Negative thoughts.
Liesbeth Venema
doi: 10.1038/433463a
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Top of pageNews and Views
Astronomy: Hot pursuit of missing matter p465
Astronomers are going to extraordinary lengths in the quest to tot up the 'ordinary' matter in the Universe. The latest initiative has probed hot gas in intergalactic space by means of an X-ray lighthouse.
J. Michael Shull
doi: 10.1038/433465a
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Evolutionary developmental biology: How and why to spot fly wings p466
How can different species evolve different physical features despite using similar molecular toolkits? Studies of wing colour development in fruitflies point to specific changes in a gene's regulatory region.
Paul M. Brakefield and Vernon French
doi: 10.1038/433466a
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Cell biology: Holding sisters for repair p467
When a DNA molecule breaks, its complementary copy can be used as a template for repair. A familiar protein complex is recruited to the damaged site, keeping it close to the undamaged copy.
Tatsuya Hirano
doi: 10.1038/433467a
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Mycology: To be or not to be a lichen p468
David Hawksworth
doi: 10.1038/433468a
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Life: In search of the simplest cell p469
Top-down, bottom-up; RNA-based, lipid-based; theory, experiment — there are many different ways of investigating what constitutes a 'minimal cell'. Progress requires finding common themes between them.
E?rs Szathmáry
doi: 10.1038/433469a
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100 and 50 years ago p469
doi: 10.1038/433469b
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Surface chemistry: Approximate challenges p470
There is growing evidence that the usual approach to modelling chemical events at surfaces is incomplete — an important concern in studies of the many catalytic processes that involve surface reactions.
Greg Sitz
doi: 10.1038/433470a
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Physiology: A welcome shortage of breath p471
The respiratory systems of animals must guarantee an efficient oxygen supply. But it seems that, in some insects, they have evolved to restrict the flow of oxygen too.
Thorsten Burmester
doi: 10.1038/433471a
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Atmospheric physics: Seeing the light p471
Karl Ziemelis
doi: 10.1038/433471b
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RNA interference: Methylation mystery p472
Tiny RNA molecules called microRNAs are important in development, and are thought to function by causing the degradation of matching messenger RNAs. That may not be their only mode of action, however.
Michael Ronemus and Rob Martienssen
doi: 10.1038/433472a
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research highlights p474
doi: 10.1038/433474a
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Top of pageBrief Communications
Burrowing mechanics: Burrow extension by crack propagation p475
A worm minimizes its energy expenditure as it forges a path through mud sediment.
Kelly M. Dorgan, Peter A. Jumars, Bruce Johnson, B. P. Boudreau and Eric Landis
doi: 10.1038/433475a
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Nanotechnology: 'Buckypaper' from coaxial nanotubes p476
M. Endo, H. Muramatsu, T. Hayashi, Y. A. Kim, M. Terrones and M. S. Dresselhaus
doi: 10.1038/433476a
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Top of pageBrief Communications Arising
Biochemistry: Role of PQQ as a mammalian enzyme cofactor? pE10
Leigh M. Felton and Chris Anthony
doi: 10.1038/nature0垃圾
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Biochemistry: Is pyrroloquinoline quinone a vitamin? pE10
Robert Rucker, David Storms, Annemarie Sheets, Eskouhie Tchaparian and Andrea Fascetti
doi: 10.1038/nature03323
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Biochemistry: Is pyrroloquinoline quinone a vitamin? (Reply) pE11
Takaoki Kasahara and Tadafumi Kato
doi: 10.1038/nature03324
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Top of pageProgress
Regulation of cap-dependent translation by eIF4E inhibitory proteins p477
Joel D. Richter and Nahum Sonenberg
doi: 10.1038/nature03205
Abstract | Full Text | PDF (498K)
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Top of pageArticles
Chance caught on the wing: cis-regulatory evolution and the origin of pigment patterns in Drosophila p481
Nicolas Gompel, Benjamin Prud'homme, Patricia J. Wittkopp, Victoria A. Kassner and Sean B. Carroll
doi: 10.1038/nature03235
Abstract | Full Text | PDF (427K) | Supplementary information
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Structural basis of actin filament nucleation and processive capping by a formin homology 2 domain p488
Takanori Otomo, Diana R. Tomchick, Chinatsu Otomo, Sanjay C. Panchal, Mischa Machius and Michael K. Rosen
doi: 10.1038/nature03251
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Top of pageLetters to Nature
The mass of the missing baryons in the X-ray forest of the warm?hot intergalactic medium p495
Fabrizio Nicastro, Smita Mathur, Martin Elvis, Jeremy Drake, Taotao Fang, Antonella Fruscione, Yair Krongold, Herman Marshall, Rik Williams and Andreas Zezas
doi: 10.1038/nature03245
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Creation of visible artificial optical emissions in the aurora by high-power radio waves p498
Todd. R. Pedersen and Elizabeth A. Gerken
doi: 10.1038/nature03243
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Observation of random-phase lattice solitons p500
Oren Cohen, Guy Bartal, Hrvoje Buljan, Tal Carmon, Jason W. Fleischer, Mordechai Segev and Demetrios N. Christodoulides
doi: 10.1038/nature03267
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Conversion of large-amplitude vibration to electron excitation at a metal surface p503
Jason D. White, Jun Chen, Daniel Matsiev, Daniel J. Auerbach and Alec M. Wodtke
doi: 10.1038/nature03213
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Low European methyl chloroform emissions inferred from long-term atmospheric measurements p506
Stefan Reimann, Alistair J. Manning, Peter G. Simmonds, Derek M. Cunnold, Ray H. J. Wang, Jinlong Li, Archie McCulloch, Ronald G. Prinn, Jin Huang, Ray F. Weiss, Paul J. Fraser, Simon O'Doherty, Brian R. Greally, Konrad Stemmler, Matthias Hill and Doris Folini
doi: 10.1038/nature03220
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Global azimuthal seismic anisotropy and the unique plate-motion deformation of Australia p509
Eric Debayle, Brian Kennett and Keith Priestley
doi: 10.1038/nature03247
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Effective leadership and decision-making in animal groups on the move p513
Iain D. Couzin, Jens Krause, Nigel R. Franks and Simon A. Levin
doi: 10.1038/nature03236
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Insects breathe discontinuously to avoid oxygen toxicity p516
Stefan K. Hetz and Timothy J. Bradley
doi: 10.1038/nature03106
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Asymptotic prey profitability drives star-nosed moles to the foraging speed limit p519
Kenneth C. Catania and Fiona E. Remple
doi: 10.1038/nature03250
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CD36 is a sensor of diacylglycerides p523
Kasper Hoebe, Philippe Georgel, Sophie Rutschmann, Xin Du, Suzanne Mudd, Karine Crozat, Sosathya Sovath, Louis Shamel, Thomas Hartung, Ulrich Z?hringer and Bruce Beutler
doi: 10.1038/nature03253
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Plastid proteins crucial for symbiotic fungal and bacterial entry into plant roots p527
Haruko Imaizumi-Anraku, Naoya Takeda, Myriam Charpentier, Jillian Perry, Hiroki Miwa, Yosuke Umehara, Hiroshi Kouchi, Yasuhiro Murakami, Lonneke Mulder, Kate Vickers, Jodie Pike, J. Allan Downie, Trevor Wang, Shusei Sato, Erika Asamizu, Satoshi Tabata, Makoto Yoshikawa, Yoshikatsu Murooka, Guo-Jiang Wu, Masayoshi Kawaguchi, Shinji Kawasaki, Martin Parniske and Makoto Hayashi
doi: 10.1038/nature03237
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Interaction network containing conserved and essential protein complexes in Escherichia coli p531
Gareth Butland, José Manuel Peregrín-Alvarez, Joyce Li, Wehong Yang, Xiaochun Yang, Veronica Canadien, Andrei Starostine, Dawn Richards, Bryan Beattie, Nevan Krogan, Michael Davey, John Parkinson, Jack Greenblatt and Andrew Emili
doi: 10.1038/nature03239
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Nanoarchaeum equitans creates functional tRNAs from separate genes for their 5'- and 3'-halves p537
Lennart Randau, Richard Münch, Michael J. Hohn, Dieter Jahn and Dieter S?ll
doi: 10.1038/nature03233
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Chemical structure and biological activity of the Caenorhabditis elegans dauer-inducing pheromone p541
Pan-Young Jeong, Mankil Jung, Yong-Hyeon Yim, Heekyeong Kim, Moonsoo Park, Eunmi Hong, Weontae Lee, Young Hwan Kim, Kun Kim and Young-Ki Paik
doi: 10.1038/nature03201
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Structure and different conformational states of native AMPA receptor complexes p545
Terunaga Nakagawa, Yifan Cheng, Elizabeth Ramm, Morgan Sheng and Thomas Walz
doi: 10.1038/nature03328
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Top of pageNaturejobs
The places to be p551
Paul Smaglik
doi: 10.1038/nj7025-551a
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The familial balancing act p552
From the loneliness of long-distance love to the practicality of new relocation services, Sally Goodman looks at solutions to the two-body problem.
Sally Goodman
doi: 10.1038/nj7025-552a
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Graduate Journal: Tough questions p554
Tobias Langenhan
doi: 10.1038/nj7025-554a
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Nuts & Bolts p554
Deb Koen
doi: 10.1038/nj7025-554b
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Movers p554
doi: 10.1038/nj7025-554c
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Top of pageFutures
Play it again, Psam p556
It's all in your mind ... isn't it?
Ian Stewart
doi: 10.1038/433556a
Full Text | PDF (225K)
