Tạp chí khoa học số 2006-03-10

10 March 2006 | $10 Need More Information? Give Us A Call: Stratagene USA and Canada Order: (800) 424-5444 x3 Technical Services: (800) 894-1304 x2 Stratagene Japan K.K. Order: 03-5159-2060 Technical Services: 03-5159-2070 AMPLIFICATION CELL BIOLOGY CLONING MICROARRAYS NUCLEIC ACID ANALYSIS PROTEIN FUNCTION & ANALYSIS QUANTITATIVE PCR SOFTWARE SOLUTIONS www.stratagene.com Stratagene Europe Order: 00800-7000-7000 Technical Services: 00800-7400-7400 Performance runs in the family. Choose the personal QPCR system that’s right for you. Mx3005P ™ System Most Flexible Stratagene now offers two affordable, fully-featured quantitative PCR (QPCR) systems. The new five-color Mx3005P ™ QPCR System includes expanded features to support a wider range of real-time QPCR applications, such as simultaneous five-target detection and alternative QPCR probe chemistries. The Mx3000P ® QPCR System is still the most affordably priced four-color 96-well system available. Mx3000P ® is a registered trademarkof Stratagene in the United States. Mx3005P ™ is a trademarkof Stratagene in the United States. Purchase of this product is accompanied by a license under the foreign counterparts of U.S. PatentNos. 4,683,195, 4,683,202 and 4,965,188 coveringthe Polymerase Chain Reaction (“PCR”) process,where such process is covered by patents. This instrument is an Authorized ThermalCycler for use with applications licenses available from Applied Biosystems.Its use with Authorized Reagents alsoprovides a limited PCR license in accordance with the label rights accompanying such reagents. • A four- or five-color instrument, with user-selected filters • Advanced optical system design for true multiplexing capability, and wider application support • QPCR Software with enhanced data analysis and export functionality Mx3000P ® System Most Affordable Ni Sepharose ™ products from GE Healthcare give you greater flexibility and the highest binding capacity available for histidine-tagged protein purification. They also assure maximum target protein activity, thanks to their tolerance of a wide range of additives and negligible nickel ion leakage. His MultiTrap ™ prepacked multiwell plates let you directly apply unclarified lysate for greater convenience and minimized degradation of sensitive target proteins. Ni Sepharose is also available prepacked in His SpinTrap ™ , His GraviTrap ™ , HisTrap ™ and bulk packs to ensure maximum flexibility in histidine-tagged protein purification. www.gehealthcare.com/his GE Healthcare © 2006 General Electric Company - All rights reserved. GE Healthcare Bio-Sciences AB, a General Electric Company. Greater flexibility in histidine-tagged protein purification GE01-06 COVER Saturn’s enigmatic moon Enceladus is a jumbled world of fresh snow plains, old cratered terrains, and long cracks dusted in green organic material. A special section in this issue presents multiple views of Enceladus taken from the Cassini spacecraft during three close flybys. See page 1388. Image: NASA/Jet Propulsion Laboratory/ C. C. Porco www.sciencemag.org SCIENCE VOL 311 10 MARCH 2006 1333 CONTENTS CONTENTS continued >> DEPARTMENTS 1339 Science Online 1341 This Week in Science 1347 Editors’ Choice 1350 Contact Science 1353 NetWatch 1355 Random Samples 1375 Newsmakers 1485 New Products 1486 Science Careers EDITORIAL 1345 Summers and Harvard by Donald Kennedy Volume 311, Issue 5766 SPECIAL SECTION Cassini at Enceladus NEWS OF THE WEEK Last-Minute Nuclear Deal Has Long-Term Repercussions 1356 The Sun’s Churning Innards Foretell 1357 More Solar Storms NASA Agrees to Review What’s on the Chopping Block 1359 SCIENCESCOPE 1359 Dates Revise Easter Island History 1360 >>Science Express Report by T. L. Hunt and C. P. Lipo Theory of Shock Waves Clears Up the Puzzling 1361 Graininess of Crystals Austria’s Bid for an Instant MIT Meets Opposition 1363 From Researchers Legislator Wants NSF to Offer $1 Billion Energy Prize 1363 NEWS FOCUS The End of Angkor 1364 Local Elites Cast New Light on Angkor’s Rise Samuel Bodman: With Energy to Spare, an Engineer 1369 Makes the Case for Basic Research A Dose of Reform to Treat the Malaise 1371 Gripping French Science Speciation Standing in Place 1372 1364 INTRODUCTION Tiger, Tiger, Burning Bright 1388 PERSPECTIVES Enceladus: Cosmic Gymnast, Volatile Miniworld 1389 J. S. Kargel Does Enceladus Govern Magnetospheric Dynamics at Saturn? 1391 M. G. Kivelson RESEARCH ARTICLES Cassini Observes the Active South Pole of Enceladus 1393 C. C. Porco et al. Cassini Encounters Enceladus: Background and the 1401 Discovery of a South Polar Hot Spot J. R. Spencer et al. REPORTS Identification of a Dynamic Atmosphere at 1406 Enceladus with the Cassini Magnetometer M. K. Dougherty et al. The Interaction of the Atmosphere of Enceladus 1409 with Saturn’s Plasma R. L. Tokar et al. Enceladus’ Varying Imprint on the Magnetosphere of Saturn 1412 G. H. Jones et al. Cassini Dust Measurements at Enceladus and Implications 1416 for the Origin of the E Ring F. Spahn et al. Cassini Ion and Neutral Mass Spectrometer: 1419 Enceladus Plume Composition and Structure J. H. Waite Jr. et al. Enceladus’ Water Vapor Plume 1422 C. J. Hansen et al. Composition and Physical Properties of Enceladus’ Surface 1425 R. H. Brown et al. Advance your geneexpression research with standardized solutions for RNA purification! QIAGEN RNA solutions standardize the purification of RNA from biological samples. Benefits include: ■ Reliability — highly pure, intact RNA for standardized results in all downstream applications ■ Convenience — easy-to-use kits with minimal protocol steps ■ Speed — ready-to-use RNA purified in as little as 25 minutes ■ Versatility — manual and automated kits for a wide range of sample types, sizes, and throughputs For up-to-date trademarks anddisclaimers, see www.qiagen.com . GEXRNA0106S1WW © 2006 QIAGEN, all rights reserved. Systems Biology — RNA Purification Standardized RNA solutions guarantee comparable results WWW. QIA GEN . C OM 10 20 30 40 50 60 70 0 2419 29 34 39 44 49 54 59 64 Purification of high-quality RNA Convenient RNA purification Visit www.qiagen.com/goto/RNAsolutions to find out more! www.sciencemag.org SCIENCE VOL 311 10 MARCH 2006 1335 CONTENTS continued >> SCIENCE EXPRESS www.sciencexpress.org PHYSICS Generating Optical Schrödinger Kittens for Quantum Information Processing A. Ourjoumtsev, R. Tualle-Brouri, J. Laurat, P. Grangier Subtraction of a photon from a squeezed coherent light pulse produces a small flying Schrödinger cat state (with an unbound photon), an essential element for quantum communication. 10.1126/science.1122858 GENETICS Genome-Wide Detection of Polymorphisms at Nucleotide Resolution with a Single DNA Microarray D. Gresham et al. Hybridization of yeast DNA from a test strain to a microarray with redundant reference DNA simply and rapidly identifies most of the polymorphisms between two strains. 10.1126/science.1123726 ARCHAEOLOGY Late Colonization of Easter Island T. L. Hunt and C. P. Lipo Radiocarbon dates imply that voyaging Polynesians arrived on Easter Island around 1200 A.D., later than previously thought, and soon began depleting timber and other natural resources and erecting statues. >> News story p. 1360 10.1126/science.1121879 PLANT BIOLOGY Rice Domestication by Reducing Shattering C. Li, A. Zhou, T. Sang The retention of rice grains on the plant after ripening—a trait important for domestication—is the result of a single nucleotide change in a transcription factor gene. 10.1126/science.1123604 CONTENTS BREVIA ATMOSPHERIC SCIENCE Diffusive Separation of the Lower Atmosphere 1429 Y. Adachi, K. Kawamura, L. Armi, R. F. Keeling As long predicted, diffusion can overcome turbulence in the troposphere under specific conditions to separate heavy and light atoms and molecules. RESEARCH ARTICLE STRUCTURAL BIOLOGY Structure of the Hydrophilic Domain of 1430 Respiratory Complex I from Thermus thermophilus L. A. Sazanov and P. Hinchliffe The x-ray crystal structure of the peripheral part of the largest bacterial respiratory electron-transport complex shows the folds, contacts, and positions of the redox cofactors. REPORTS CHEMISTRY Ultrafast Interfacial Proton-Coupled Electron Transfer 1436 B. Li, J. Zhao, K. Onda, K. D. Jordan, J. Yang, H. Petek Return of an electron from a methanol film to a semiconductor induces rapid (30 femtoseconds) stabilizing motion in the substrate and coupled transfer of a proton. CHEMISTRY Observation of Feshbach Resonances in the 1440 F + H 2 → HF + H Reaction M. Qiu et al. Signatures of H 2 CO Photodissociation from 1443 Two Electronic States H. M. Yin, S. H. Kable, X. Zhang, J. M. Bowman Spectroscopy and computations reveal the nuclear vibrations and other motions involved in the dissociations of excited, transient molecules and in collision reactions. >> Perspective p. 1383 LETTERS Finding Good in the Bad and Vice Versa D. Johns 1376 Diversity in Tropical Forests W. F. Laurance Genetic Polymorphism of Fc J. P. Pandey Response J. M. Woof Hyposmocoma molluscivora Description D. Rubinoff and W. P. Haines GPS: A Military/Civilian Collaboration J. F. Zumberge Decline of Vultures in Asia R. E. Green BOOKS ET AL. The Weather Makers How Man Is Changing 1379 the Climate and What It Means for Life on Earth T. Flannery; The Weather Makers The History and Future Impact of Climate Change A. Lane reviewed by B. Chameides POLICY FORUM Fusion Power: Will It Ever Come? 1380 W. E. Parkins PERSPECTIVES Total Information Awareness for Worm Genetics 1381 S. R. Eddy >> Report p. 1481 Five Golden Rings 1382 D. W. Christianson >> Report p. 1464 Resonances in Reaction Dynamics 1383 R. N. Zare >> Reports pp. 1440 and 1443 One Misfolded Protein Allows Others to Sneak By 1385 G. P. Bates >> Report p. 1471 Fungi, Weathering, and the Emergence of Animals 1386 L. A. Derry >> Report p. 1446 online! apply Learn Molecular Biology in 2 Weeks! This intensive, two-week course emphasizes hands-on molecular biology laboratory work and covers a wide variety of topics and techniques. Topics/Techniques: :: gene cloning (cDNA and genomic) :: gene expression analysis :: PCR and quantitative RT-PCR :: genomics and bioinformatics :: DNA sequencing and DNA fingerprinting :: RNAi, siRNA and microarrays :: and much more – visit our website for a complete list Application Information: No previous experience in molecular biology is required or expected. Fifty participants per session will be selected from a variety of disciplines and academic backgrounds. FEE: $4000 per participant includes lab manual, use of all equipment and supplies, and room and board (all rooms are singles). APPLICATION DEADLINE: First come, first served (apply now!). PAYMENT DEADLINE: Three weeks following receipt of your application. Late applications will be accepted! Your application should include a recent resume and one paragraph explaining your reasons for taking the course. Please specify the session to which you are applying (1, 2, or 3) and indicate a second choice from one of the other sessions. We are pleased to announce the twenty-first annual Molecular Biology Summer Workshops, sponsored by New England Biolabs in conjunction with Smith College. Workshops are held at the Clark Science Center, Smith College, Northampton, MA, USA. Over 3,000 people have graduated from this intensive training program in the past twenty years. Molecular Biology Summer Workshops For additional information, please call (413) 247-3004 or visit the Summer Workshop web site: http://www.science.smith.edu/neb 21st ANNUAL New England Biolabs the leader in enzyme technology when: Session 1: June 4 – June 17, 2006 Session 2: June 18 – July 1, 2006 Session 3: July 9 – July 22, 2006 where: Clark Science Center Smith College Northampton, MA USA to apply: apply online at http://www.science.smith.edu/neb or Mail a recent resume and one paragraph explaining your interest to: Molecular Biology Summer Workshops Dr. Steven A. Williams Clark Science Center Smith College Northampton, MA 01063 . Porco www.sciencemag.org SCIENCE VOL 311 10 MARCH 2006 1333 CONTENTS CONTENTS continued >> DEPARTMENTS 1339 Science Online 1341 This Week in Science 1347 Editors’ Choice 1350 Contact Science 1353. activation. www.cellsciences.com www.cellsciences.com cell sciences Cell Sciences 480 Neponset Street, Bldg. 12A Canton, MA 02021 USA Tel: 781 828-0610 Fax: 781 828-0542 email: info@cellsciences.com 888. Williams Clark Science Center Smith College Northampton, MA 01063 www.sciencemag.org SCIENCE VOL 311 10 MARCH 2006 1337 CONTENTS continued >> REPORTS CONTINUED ATMOSPHERIC SCIENCE Late Precambrian