Volume 433 Number 7023 pp179-338封面故事：太阳系外的巨型行星
近年来已有超过100颗绕太阳系附近的恒星运行的巨型行星被发现。研究人员是通过高精度“多普勒”分光镜发现太阳系外的这些巨型行星的，但在有可能对来自这些行星的光进行直接探测之前，它们的化学、结构和演化等方面的谜底将仍然无法揭开。到目前为止，尚未有经过证实的对太阳系外行星的直接探测。为了使科学家们期盼的这一目标离我们更近一些，Adam Burrows对这样一个行星上的大气层会是什么样子的做了理论分析。如果观测天文学家们对他们所要寻找的东西了解更多，他们就会更容易找到它。本期封面所示为天文学家想象出的一颗巨型行星从诞生到现在的演化序列（作者Lynette Cook），最后阶段（即图上最小的一个）实际上是用“旅行者”号飞船拍摄到的木星的一个图像来代替的。
“囊泡刺激素”（FSH）的结构
“囊泡刺激素”（FSH）在男性和女性的生殖中都扮演一个中心角色，它是通过其受体刺激睾丸和卵巢功能来发挥作用的。现在，研究人员已经确定了人类FSH的结构，它存在于与其受体的细胞外部分形成的一种复合物中。该结构显示了一种似乎适合于所有糖蛋白激素的结合机制。从分子水平上来了解FSH与其受体的相互作用，可帮助设计避孕药和治疗不育症的新方法。
Pokemon可能是一个抗肿瘤治疗目标
Pokemon是一种转录抑制因子，在许多不同的胚胎组织的细胞分化中扮演关键角色。现在，研究发现，它与肿瘤形成也有关系。Pokemon在纤维细胞组织培养中的过度表达，会抑制致癌基因诱发的衰老和自杀，导致形成赘生组织。Pokemon专门抑制ARF肿瘤抑制因子的转录。微阵列和肿瘤组织阵列分析显示，Pokemon在有恶性血癌和固体肿瘤的患者体内异常表达。作为一种与ARF的抑制有关的原致癌基因，Pokemon可能是治疗干预的一个重要目标。
低质量伴星AB Dor C被观测到
快速旋转的年轻恒星AB Doradus (AB Dor)被认为有一个低质量伴星，该伴星是作为天文学上的一种“晃动”被探测到的。实践证明，这个伴星难以观测，“哈伯望远镜”1997年曾试图探测它，但却失败了。现在，建造用来对太阳系外行星进行成像的一台新仪器观测到了AB Doradus的这颗暗淡伴星。安装在位于智利的“欧洲南方天文台”的这个高对比适应性光学装置NACO SDI照相机发现，该伴星（现在命名为AB Dor C）作为一颗恒星来说质量非常小（为木星质量的90倍）。它距离AB Dor非常近，比最新恒星模型预测的结果温度低400摄氏度，亮度小2.5倍。这一发现表明，大多数已知的褐矮星和太阳系外行星要比以前人们所想的更重，该新发现对于设计用来寻找太阳系外行星的未来照相机将是重要的。
“卡西尼”飞船的新发现
当“卡西尼”飞船接近土星时，所搭载的尘埃探测器发现，土星是运动速度超过100公里/秒的微粒的一个来源。这些微粒中绝大多数现在被认为来源于土星外层致密环的外围。对该区域的物质进行实地分析是不可能的，这是因为，由于存在碰撞损坏危险，并未安排该飞船近距离从致密环上空飞过。然而，“卡西尼” 飞船的这一新发现表明，在距致密环一个安全距离处，利用“卡西尼” 飞船上的尘埃探测器是可以做到这一点的。另外，现在似乎可以说，来自行星磁气圈的高速颗粒的排放是太阳系的一个普遍现象。
英特尔研制成全硅激光器
随着信息技术中光电子装置用量的增长，对光进行操控已变得与对电子进行操控几乎同样重要。遗憾的是，现代微电子技术中的功臣硅在光学应用中几乎毫无用处。科学家为克服硅的缺陷做了大量努力，“诱使”硅来处理光的方法也在研发当中，但光应用中的一个关键部件激光器却存在问题。去年，科学家研制出了一个硅激光器，但该激光器需要用数米长的光纤。现在，英特尔研究实验室的研究人员研制成做在一个硅芯片上的一种全硅激光器。该装置是紧凑型的，可以方便集成进其他硅元件中。基于硅的光电子技术的未来似乎是光明的。
西太平洋地区“更新世”的气候变化
来自西太平洋“暖池”的关于“更新世”气候变化的第一个高分辨率记录，为该地区的气候变化提供了重要信息，它对于我们了解地球的气候是怎样进入已经持续了过去80万年的冰期模式的将具有参考价值。该记录采用浮游生物有孔虫类体内的Mg/Ca比例作为过去175万年间海洋表面温度的一种代理指标。新的研究结果显示，该地区有一个持续很长时间的稳定期，这与大气中CO2浓度逐渐减少是冰川化的诱因的观点是不一致的。相反，通过区域环流的变化实现的太平洋表面温度的重新分布有可能影响了全球气候。这个结论支持科学家最近对热带地区对未来气候变化的响应的担忧。
埃塞俄比亚发现原始人化石
原始人Ardipithecus ramidus距今450万年的化石的发现，增加了我们关于人类演化过程中一个迷人阶段的知识，这个阶段在原始人离开森林、前往开阔稀树草原之前。这一阶段的化石发现很少，但位于埃塞俄比亚Gona地区的化石层已经产出了来自至少9个原始人的化石材料。这些化石材料周围的情况表明，这些原始人生活在一个有适度降雨的林地和草地环境中。
南极鸟类化石成为鸟类起源争论焦点
来自南极洲的一种鸟类的罕见化石，成为关于现代鸟类起源的一场争论的焦点。该化石据信是现代鸭子和鹅的一个近亲，生活在距今约7000万年前的白垩纪末。如果说现代鸟类的祖先是这个时期前后的恐龙，那将是一种有争议的观点。在此之前，化石证据曾表明，“现代”鸟类只是在距今6500万年前恐龙灭绝后才出现的。尽管来自分子生物学的证据表明，现代鸟类存在的时间远在这个时间之前，而化石证据却总有人坚定支持。在古生物学的这一领域，争论还将继续下去。
cAMP信号与粘菌体系的通信方式
粘菌（Dictyostelium discoidium）是深受细胞生物学家欢迎的一种研究多细胞生命形式的模型。当食物短缺时，它的自由生活的土壤变形虫就会聚集形成一种多细胞体，该多细胞体分异并产生孢子。Gerisch等人在上个世纪70年代所做的工作表明，这种聚集由脉冲式的环状AMP控制，而现在用缺少cAMP依赖性蛋白激酶-A的突变体所做的实验，让我们看到了这一体系是怎样进行工作的。细胞通过一个cAMP信号中继来进行通信，以生成向外传播的cAMP波，这种波控制细胞的向内运动。数值模拟显示，自组织是由一个基因回路来微调的，后者通过蛋白激酶-A发挥作用，以形成一个总体波形；没有它时，会形成一系列不连在一起的螺旋核。其他体系，如心脏肌肉，可能以类似方式发挥作用，以抑制有害的螺旋波。
反映肌肉运动的X-射线影片
昆虫通过用微小的肌肉组织前后拍打其翅膀来飞行，这些肌肉组织是动物界中最强大的运动肌。这些肌肉展现出伸展依赖性促动的一种增强形式，在某种程度上，这种促动是几乎所有肌肉组织都具有的一种性能。Dickinson等人通过将一束狭窄的、高强度的X-射线对准用绳子系着的、正在飞行的果蝇的飞行肌肉，直接测定出了一个正在工作状态的飞行肌肉中的结构变化。他们将所获数据与虚拟现实模拟相结合，做成了反映肌肉循环运动的X-射线影片，这种循环运动使肌肉每秒钟收缩和舒展200次。这些结果对于了解包括心脏在内的所有肌肉是怎样工作的具有参考意义。
本期目录：
Editorials
Einstein is dead p179
Until its next revolution, much of the glory of physics will be in engineering. It is a shame that the physicists who do so much of it keep so quiet about it.
doi: 10.1038/433179a
Full Text | PDF (48K)
--------------------------------------------------------------------------------
Tales of the unexpected p179
Unfettered research sometimes leads to highly serendipitous discoveries.
doi: 10.1038/433179b
Full Text | PDF (48K)
--------------------------------------------------------------------------------
Top of pageNews
Titan team claims just deserts as probe hits moon of crème br?lée p181
European space craft successfully parachutes down to Saturn's moon.
Alison Abbott
doi: 10.1038/433181a
Full Text | PDF (107K)
--------------------------------------------------------------------------------
Georgia court bans biology textbook stickers p182
"Evolution is a theory, not a fact" stickers banned from school texts.
Jessica Ebert
doi: 10.1038/433182a
Full Text | PDF (239K)
--------------------------------------------------------------------------------
All parties on edge as NIH delays open-access briefing p182
Both sides of the open-access debate anxious about potential policy changes.
Erika Check
doi: 10.1038/433182b
Full Text | PDF (239K)
--------------------------------------------------------------------------------
Indian Ocean fault line poses threat of further earthquakes p183
Energy from 26 December quake could hasten the next rupture.
Emma Marris
doi: 10.1038/433183a
Full Text | PDF (220K)
--------------------------------------------------------------------------------
Pasteur board quits in bid to resolve crisis at troubled institute p183
Staff of Parisian biomedical research facility resign in mass protest.
Declan Butler
doi: 10.1038/433183b
Full Text | PDF (220K)
--------------------------------------------------------------------------------
Science lobby urges UK to divert funds from military fields p184
Public funding too focused on weapons-based research, says report.
Philip Ball
doi: 10.1038/433184a
Full Text | PDF (141K)
--------------------------------------------------------------------------------
Antinuclear groups push to keep treaty review in the air p184
Nuclear Non-Proliferation Treaty at critical point, observers say.
Michael Hopkin
doi: 10.1038/433184b
Full Text | PDF (141K)
--------------------------------------------------------------------------------
Brain-scan ethics come under the spotlight p185
Scientists thrash out policies for dealing with scan results.
Erika Check
doi: 10.1038/433185a
Full Text | PDF (208K)
--------------------------------------------------------------------------------
news in brief p186
doi: 10.1038/433186a
Full Text | PDF (149K)
--------------------------------------------------------------------------------
Top of pageNews Features
All pain, no gain? p188
Exercise is good for you, or so we always thought. But, as Alison Abbott learns, your genes don't always cooperate.
doi: 10.1038/433188a
Full Text | PDF (645K)
See also: Editor's summary
--------------------------------------------------------------------------------
The premier division p190
Since he took over as Harvard president in 2001, Larry Summers' style and vision have divided the university. As his plans for expansion step up a gear, Summers tells Helen Pearson why it is time for Cambridge to face up to the need for change.
doi: 10.1038/433190a
Full Text | PDF (1,054K)
--------------------------------------------------------------------------------
Top of pageCorrespondence
Croatian minister rejects 'meddling' claim p193
Mediterranean Institute's link with university is intended to ensure academic freedom.
Dragan Primorac
doi: 10.1038/433193a
Full Text | PDF (57K)
--------------------------------------------------------------------------------
Insect collection ready to spread its wings p193
Quentin D. Wheeler
doi: 10.1038/433193b
Full Text | PDF (57K)
--------------------------------------------------------------------------------
Alternative views of amphibian toe-clipping p193
W. Chris Funk, Maureen A. Donnelly and Karen R. Lips
doi: 10.1038/433193c
Full Text | PDF (57K)
--------------------------------------------------------------------------------
Top of pageBooks and Arts
The Einstein chronicles p195
Two volumes of correspondence put Einstein's work in a historical context.
doi: 10.1038/433195a
Full Text | PDF (113K)
--------------------------------------------------------------------------------
Relativity revisited p196
doi: 10.1038/433196a
Full Text | PDF (227K)
--------------------------------------------------------------------------------
Science in culture p197
A disputed portrait of Robert Hooke may in fact show a contemporary.
Philip Ball
doi: 10.1038/433197a
Full Text | PDF (201K)
--------------------------------------------------------------------------------
A novel view of global warming p198
doi: 10.1038/433198a
Full Text | PDF (288K)
--------------------------------------------------------------------------------
Top of pagePhysics detective
Schr?dinger's mousetrap p200
Part 1: The trap is primed.
Ian Stewart
doi: 10.1038/433200a
Full Text | PDF (1,087K)
--------------------------------------------------------------------------------
Top of pageNews and Views
Endocrinology: Fertility hormone in repose p203
Egg and sperm development are triggered when follicle-stimulating hormone binds to its receptor. A three-dimensional structural snapshot reveals how the hormone slots into its receptor, and how specificity of binding is ensured.
James A. Dias
doi: 10.1038/433203a
Full Text | PDF (197K)
See also: Editor's summary
--------------------------------------------------------------------------------
Climatology: Will soil amplify climate change? p204
It had been thought by some that rising atmospheric temperatures would have no effect on the rate at which carbon is released from the soil. A study that revisits the data behind this theory now finds otherwise.
David Powlson
doi: 10.1038/433204a
Full Text | PDF (105K)
--------------------------------------------------------------------------------
Evolution: A taste for mimicry p205
Looking inedible is a great way to deter predators, but the warning signs must be learnt first. It seems that unpalatable species employ some unexpected strategies to make the education a quick one.
Graeme D. Ruxton and Michael P. Speed
doi: 10.1038/433205a
Full Text | PDF (154K)
--------------------------------------------------------------------------------
Astronomy: Weighing the baby p207
Mass is the fundamental parameter in stellar astrophysics, but measuring mass is difficult, especially for young stars. A study of a youthful neighbour of the Sun provides insight into the accuracy of widely used calibrations.
I. Neill Reid
doi: 10.1038/433207a
Full Text | PDF (152K)
See also: Editor's summary
--------------------------------------------------------------------------------
Signal transduction: A new canon p208
Muscle development in vertebrates relies on signals transmitted from proteins of the Wnt family. But which molecules form the relay that transfers this signal to the cell nucleus? The answer is unexpected.
Olivier Pourquié
doi: 10.1038/433208a
Full Text | PDF (836K)
--------------------------------------------------------------------------------
100 and 50 years ago p209
doi: 10.1038/433209a
Full Text | PDF (821K)
--------------------------------------------------------------------------------
research highlights p210
doi: 10.1038/433210a
Full Text | PDF (101K)
--------------------------------------------------------------------------------
Top of pageBrief Communications
Animal mimicry: Choosing when to be a cleaner-fish mimic p211
A dangerous fish can discard a seemingly harmless disguise to suit its circumstances.
Isabelle M. C?té and Karen L. Cheney
doi: 10.1038/433211a
First paragraph | Full Text | PDF (350K) | Supplementary information
--------------------------------------------------------------------------------
Behavioural ecology: Transient sexual mimicry leads to fertilization p212
Roger T. Hanlon, Marié-Jose Naud, Paul W. Shaw and Jon N. Havenhand
doi: 10.1038/433212a
First paragraph | Full Text | PDF (213K) | Supplementary information
--------------------------------------------------------------------------------
Top of pageBrief Communications Arising
Evolutionary genomics: Codon bias and selection on single genomes pE5
Matthew W. Hahn, Jason G. Mezey, David J. Begun, John H. Gillespie, Andrew D. Kern, Charles H. Langley and Leonie C. Moyle
doi: 10.1038/nature03221
First paragraph | Full Text | PDF (419K)
--------------------------------------------------------------------------------
Evolutionary genomics: Detecting selection needs comparative data pE6
Rasmus Nielsen and Melissa J. Hubisz
doi: 10.1038/nature03222
First paragraph | Full Text | PDF (68K)
--------------------------------------------------------------------------------
Evolutionary genomics: Codon volatility does not detect selection pE6
Ying Chen, J. J. Emerson and Todd M. Martin
doi: 10.1038/nature03223
First paragraph | Full Text | PDF (417K)
--------------------------------------------------------------------------------
Evolutionary genomics: Codon volatility does not detect selection (reply) pE7
J. B. Plotkin, J. Dushoff and H. B. Fraser
doi: 10.1038/nature03224
First paragraph | Full Text | PDF (415K)
--------------------------------------------------------------------------------
Top of pageYear of physics
Year of physics a celebration p213
Alison Wright, Karl Ziemelis, Leslie Sage and Karen Southwell
doi: 10.1038/433213a
Full Text | PDF (251K)
--------------------------------------------------------------------------------
1905 and all that p215
How Einstein claimed his place in the changing landscape of physics during his annus mirabilis.
John Stachel
doi: 10.1038/433215a
Full Text | PDF (825K)
--------------------------------------------------------------------------------
Einstein as icon p218
How Einstein became the personification of physics.
John D. Barrow
doi: 10.1038/433218a
Full Text | PDF (411K)
--------------------------------------------------------------------------------
Brownian motion p221
"I did not believe that it was possible to study the Brownian motion with such a precision." From a letter from Albert Einstein to Jean Perrin (1909).
Giorgio Parisi
doi: 10.1038/4垃圾1a
Full Text | PDF (166K)
--------------------------------------------------------------------------------
In and out of equilibrium p222
J. Kurchan
doi: 10.1038/nature03278
Abstract | Full Text | PDF (267K)
--------------------------------------------------------------------------------
Quantum criticality p226
Piers Coleman and Andrew J. Schofield
doi: 10.1038/nature03279
Abstract | Full Text | PDF (523K)
--------------------------------------------------------------------------------
Happy centenary, photon p230
Anton Zeilinger, Gregor Weihs, Thomas Jennewein and Markus Aspelmeyer
doi: 10.1038/nature03280
Abstract | Full Text | PDF (1,052K)
--------------------------------------------------------------------------------
In search of symmetry lost p239
Frank Wilczek
doi: 10.1038/nature03281
Abstract | Full Text | PDF (321K)
--------------------------------------------------------------------------------
The state of the Universe p248
Peter Coles
doi: 10.1038/nature03282
Abstract | Full Text | PDF (655K)
--------------------------------------------------------------------------------
A theory of everything? p257
In his later years, Einstein sought a unified theory that would extend general relativity and provide an alternative to quantum theory. There is now talk of a 'theory of everything' (although Einstein himself never used the phrase). Fifty years after his death, how close are we to such a theory?
doi: 10.1038/433257a
Full Text | PDF (179K)
--------------------------------------------------------------------------------
Top of pageResearch Article
A theoretical look at the direct detection of giant planets outside the Solar System p261
Adam Burrows
doi: 10.1038/nature03244
Abstract | Full Text | PDF (425K)
See also: Editor's summary
--------------------------------------------------------------------------------
Top of pageArticles
Structure of human follicle-stimulating hormone in complex with its receptor p269
Qing R. Fan and Wayne A. Hendrickson
doi: 10.1038/nature03206
Abstract | Full Text | PDF (697K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Role of the proto-oncogene Pokemon in cellular transformation and ARF repression p278
Takahiro Maeda, Robin M. Hobbs, Taha Merghoub, Ilhem Guernah, Arthur Zelent, Carlos Cordon-Cardo, Julie Teruya-Feldstein and Pier Paolo Pandolfi
doi: 10.1038/nature03203
Abstract | Full Text | PDF (606K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Top of pageLetters to Nature
A dynamical calibration of the mass?luminosity relation at very low stellar masses and young ages p286
Laird M. Close, Rainer Lenzen, Jose C. Guirado, Eric L. Nielsen, Eric E. Mamajek, Wolfgang Brandner, Markus Hartung, Chris Lidman and Beth Biller
doi: 10.1038/nature03225
First paragraph | Full Text | PDF (252K)
See also: Editor's summary
--------------------------------------------------------------------------------
High-velocity streams of dust originating from Saturn p289
Sascha Kempf, Ralf Srama, Mihaly Horányi, Marcia Burton, Stefan Helfert, Georg Moragas-Klostermeyer, Mou Roy and Eberhard Grün
doi: 10.1038/nature03218
First paragraph | Full Text | PDF (384K)
See also: Editor's summary
--------------------------------------------------------------------------------
An all-silicon Raman laser p292
Haisheng Rong, Ansheng Liu, Richard Jones, Oded Cohen, Dani Hak, Remus Nicolaescu, Alexander Fang and Mario Paniccia
doi: 10.1038/nature03273
First paragraph | Full Text | PDF (222K)
See also: Editor's summary
--------------------------------------------------------------------------------
Stable sea surface temperatures in the western Pacific warm pool over the past 1.75 million years p294
Thibault de Garidel-Thoron, Yair Rosenthal, Franck Bassinot and Luc Beaufort
doi: 10.1038/nature03189
First paragraph | Full Text | PDF (378K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Long-term sensitivity of soil carbon turnover to warming p298
W. Knorr, I. C. Prentice, J. I. House and E. A. Holland
doi: 10.1038/nature03226
First paragraph | Full Text | PDF (336K)
--------------------------------------------------------------------------------
Early Pliocene hominids from Gona, Ethiopia p301
Sileshi Semaw, Scott W. Simpson, Jay Quade, Paul R. Renne, Robert F. Butler, William C. McIntosh, Naomi Levin, Manuel Dominguez-Rodrigo and Michael J. Rogers
doi: 10.1038/nature03177
First paragraph | Full Text | PDF (427K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Definitive fossil evidence for the extant avian radiation in the Cretaceous p305
Julia A. Clarke, Claudia P. Tambussi, Jorge I. Noriega, Gregory M. Erickson and Richard A. Ketcham
doi: 10.1038/nature03150
First paragraph | Full Text | PDF (334K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Field parameterization and experimental test of the neutral theory of biodiversity p309
J. Timothy Wootton
doi: 10.1038/nature03211
First paragraph | Full Text | PDF (191K)
--------------------------------------------------------------------------------
Evolutionary dynamics on graphs p312
Erez Lieberman, Christoph Hauert and Martin A. Nowak
doi: 10.1038/nature03204
First paragraph | Full Text | PDF (308K) | Supplementary information
--------------------------------------------------------------------------------
Protein kinase A signalling via CREB controls myogenesis induced by Wnt proteins p317
Alice E. Chen, David D. Ginty and Chen-Ming Fan
doi: 10.1038/nature03126
First paragraph | Full Text | PDF (501K) | Supplementary information
--------------------------------------------------------------------------------
An autoregulatory circuit for long-range self-organization in Dictyostelium cell populations p323
Satoshi Sawai, Peter A. Thomason and Edward C. Cox
doi: 10.1038/nature03228
First paragraph | Full Text | PDF (390K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
A pentatricopeptide repeat protein is essential for RNA editing in chloroplasts p326
Emi Kotera, Masao Tasaka and Toshiharu Shikanai
doi: 10.1038/nature03229
First paragraph | Full Text | PDF (417K) | Supplementary information
--------------------------------------------------------------------------------
Molecular dynamics of cyclically contracting insect flight muscle in vivo p330
Michael Dickinson, Gerrie Farman, Mark Frye, Tanya Bekyarova, David Gore, David Maughan and Thomas Irving
doi: 10.1038/nature03230
First paragraph | Full Text | PDF (249K) | Supplementary information
See also: Editor's summary
--------------------------------------------------------------------------------
Top of pageNaturejobs
Closing the gap p335
Paul Smaglik
doi: 10.1038/nj7023-335a
Full Text | PDF (141K)
--------------------------------------------------------------------------------
Save now, don't pay later p336
Should young scientists be tightening their belts to save for the future? Kendall Powell compounds the interest.
Kendal Powell
doi: 10.1038/nj7023-336a
Full Text | PDF (299K)
--------------------------------------------------------------------------------
Graduate Journal: Time to explore new worlds p338
Jason Underwood
doi: 10.1038/nj7023-338a
Full Text | PDF (66K)
--------------------------------------------------------------------------------
Scientists & Societies p338
Sarah Elizabeth Staveteig
doi: 10.1038/nj7023-338b
Full Text | PDF (66K)
--------------------------------------------------------------------------------
Movers p338
doi: 10.1038/nj7023-338c
Full Text | PDF (66K)
