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Trang 5Volume 317, Issue 5846
COVER DEPARTMENTS
The red alga Chondrus crispus (Irish moss) 1827 Science Online
This image, taken with a digital 1829 This Week in Science
point-and-shoot camera, tied for first place 1834 Editors” Choice
in the photography category of the 1836 Contact Science
National Science Foundatiom/Science 2007 Visualization Challenge All the winning 1839 Random Samples 1841 Newsmakers
entries are displayed in a special feature beginning on page 1857 and online at 1879 AAAS News & Notes 1939 New Products T0 tên
wnu scien cemag.org/sciext/vis2007
‘Image: Andrea Ottensen EDITORIAL
1833 European Young Investigators byT Hunt
NEWS OF THE WEEK LETTERS
Vaccine-Related Polio Outbreak in Nigeria Raises 1842 Birds Like Music, Too A Gess 1864
Concerns Climate Change: Don't Forfeit the Game F Krupp
‘Tougher Ozone Accord Also Addresses Global Warming 1843 Climate Change: One Goal at a Time H Harvey
Panel Wants U.S Program to Retain Its Russian Roots 1845 anel Wants U.S Program to Retain Is Russian Roots BGØIKŠ cmau
SCLENCESCOPE Uncoterng the Magic in Hage Brain sinlaton 7016 —_— cin Magnetic Bain stimulation HSS ‘Aryan dol Indo-European Mythology 2s Ideology STREET Idols Indo-Et thol Ideolc 1868
11 Slows China’s : Scénario Catastrophe 1869
Polition Stews lina’ Conal Project tate) C Delécraz, L Durussel, A Fondrini, curators
A Far-South Start for Ice Age’s End 1847 %
Science Express Report by 1 Browsing 1870 EDUCATION FORUM Pharmacology in the High-School Classroom 1871 N.C Kwiek et al PERSPECTIVES 1869 ‘Tracking Polynesian Seafarers 1873 B Finney
Juantum Weirdness in the Lab 1874
‘RW Boyd, K W.C Chan, M N O'Sullivan
Deep Questions in the Tree of Life 1875
NEWS FOCUS n
A Singular Conundrum: How Odd Is Our Universe? 1848 ‘port
U.S Says No to Next Global Test of 1851 Does Our Universe Allow for Robust 1876
‘Advanced Math, Science Students Quantum Computation?
Accidents Spur a Closer Look at Risks at 1852
Biodefense Labs 189:
Setting the Forest Alight 1854 Antarctic Biodiversity 1877
Trang 6Assay technologies by QIAGEN
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Trang 7SCIENCE EXPRESS
wwwsciencexpress.org
GENETICS
Paired-End Mapping Reveals Extensive Structural Variation in the Human Genome
1.0 Korbel et al
Sequencing of structure variations over segments of DNA from two individuals of different ethnic groups showed unexpected levels of diversity
10.1126/science.1149504
GENETICS
Wasp Gene Expression Supports an Evolutionary Link Between ‘Maternal Behavior and Eusociality
ALL Tothet al
Analysis ofa set of genes expressed inthe brain of a primitive wasp shows that the care shown by worker wasps toward siblings probably evolved from maternal care behavior
10.11.26/science.1146647
CONTENTS L
CLIMATE CHANGE
Southern Hemisphere and Deep-Sea Warming Led Deglacial ‘Atmospheric CO, Rise and Tropical Warming
L Stott, A Timmermann, R Thunell
Dating of benthic versus near-surface plankton in a Pacific Ocean core shows that southern high latitudes warmed 1500 years before the tropics during the last, deglaciation
>> News story p 1847 10.11 26/science.1143791
ASTRONOMY
ABright Millisecond Radio Burst of Extragalactic Origin
D.R Lorimer, M Bailes, M.A McLaughlin, D J Narkevic, F Cranford ‘Arapid and powerful burst of radio waves is found through an analysis of archival
pulsar data, suggestive of anew class of radio bursts, perhaps from a supernova, 10.11 26/science.1147532
TECHNICAL COMMENT ABSTRACTS
OCEANS
Comment on “A Semi-Empirical Approach to Projecting Future Sea-Level Rise”
S Holgate, 5 Jevrejeva, P Woodworth, S Brewer
‘Comment on “A Semi-Empirical Approach to Projecting Future Sea-Level Rise”
T Schmith, S Johansen, P Thejll
Response to Comments on “A Semi-Empirical Approach to
Projecting Future Sea-Level Rise” 5 Rohmstorf 1866 REVIEW IEMISTRY Fluorine in Pharmaceuticals: Looking Beyond Intuiti K Miller, C Faeh, F Diederich BREVIA PALEONTOLOGY Correlated Evolution and Dietary Change in Fossil Stickleback
M.A, Purnell etal
‘Wear patterns in fossilized teeth show that Miocene sticklebacks ‘switched from surface- to bottom-feeding over 20,000 years, implying that changes in diet drove their evolution
REPORTS
PLANETARY SCIENCE
The Dark Side of the Rings of Uranus de Pateretal
Images of Uranus’ rings, which are currently oriented edge-on to Earth, reveal large changes in dust distribution since Voyager's Visit 20 yearsago, 1881 1887 1888 www.sciencemag.org SCIENCE PHYSI
Probing Quantum Commutation Rules by Addition and Subtraction of Single Photons to/from a Light Field
V Parigi A Zavatta, M Kim, M Bellini
An experiment shows that quantum addition snot commutative: Adding a single photon to alight fetd and then subtracting one produces a different result than subtracting first 1890 PHYSICS Symmetrized Characterization of Noisy Quantum Processes J Emerson et al
.A symmety-based approach dramatically reduces the number cof measurements needed to describe the decoherence of a quantum system, a necessity fr practical information storage
1893
APPLIED PHYSICS
Nuclei-induced Frequency Focusing of Electron Spin Coherence
A Greilich et al
Laser pulses can tune spin precessions of electrons in an ensemble of singly charged quantum dots to well-defined modes that remain stable inthe dark for tens of minutes
1896
CONTENTS continued >>
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Trang 9Science
REPORTS CONTINUED
GEOCHEMISTRY Late Archean Biospheric Oxygenation and 1900
‘Atmospheric Evolution ALJ Kaufinan etal
AWhiff of Oxygen Before the Great Oxidation Event? 1903 A.D Anbar et al
Sulfur isotopes and trace elements imply that oxygen levels in Earths atmosphere rose briefly 50 to 100 milion years before the major increase 24 billion years ago
ARCHAEOLOGY
Stone Adze Compositions and the Extent of 1907 Ancient Polynesian Voyaging and Trade
KD Collerson and M 1 Weisler
Isotopic and chemical data trace Polynesian adze heads on the Tuamotus to nearby island sources and to the Hawaiian Islands, 4000 km to the north, showing an extensive trade network
DEVELOPMENTAL BIOLOGY
Synchrony Dynamics During Initiation, Failure, 1911 and Rescue of the Segmentation Clock
IH Riedel-Krase, C Miller, A C Oates
‘Amodel of the segmentation clock, coupled genetic oscillators that sequentially generate the body segments of animals, successfully predicts the results of system perturbations
ECOLOGY Rapid Emergence of Baculovirus Resistanc 1916 Coding Moth Due to Dominant, Sex-Linked inheritance Š Asser-Kgiser etal
Moths have developed an unusual ype of resistance ta widely used, environmentally benign val pesticide, explaining recent damage to apple cropsin Germany and France
NEUROSCIENCE
Transcranial Magnetic Stimulation Elicits Coupled 1918 Neural and Hemodynamic Consequences
EA.Allen, 8 N Pasley, I Duong, R D Freeman
‘A procedure that targets circumscribed brain regions in people and animals suppresses and desynchronizes neural activity, effects that ate faithfully reflected by bran imaging methods > News story p28
GENETICS
Genomic Minimalism in the Early Diverging 1921 intestinal Parasite Giardia lamblia
The genome ofthe pathogenic intestinal parasite Giardia reveals simplified metabolic systems, unexpected evidence cof sexual reproduction, and specialized clases of protein, MVAAAS gto aie Aon tne heptane ae bhatt ep ae 0 917A Ying C2096 Sige ‘sone Aaartaon pasa se ‘Sg 05540896 075) pled ein aca ree Msn wih com, byt Anve aiaton 2005 Foss jean CONTENTS L GENETICS
Whole-Genome Shotgun Sequencing of Mitochondria 1927 from Ancient Hair Shafts
M.TP Gilbert etal
Mitochondrial DNA can be succesfully sequenced from woolly mammoth hair kept either frozen in permafrost or at room temperature in a museum for 200 years
STRUCTURAL BIOLOGY
Structures of the CCRS N Terminus and of a 1930
‘Tyrosine-Sulfated Antibody with HIV-1 gp120 and CD4 C Huang etal
Aconserved region inthe HIV-1 envelope glycoprotein binds toa sulfated tyrosine during entry ints host cls, providing
a possible target for therapeutics
NEUROSCIENCE
‘The Slit Receptor EVA-1 Coactivates a 1934 SAX-3/Robo-Mediated Guidance Signal in C elegans K Fujisawa, J L Wrana, J G Culotti
Trang 10IlSái-is Complements 7 Fisher fi Scientific Trewortdeaderia ‘S Thewortdlentertalenorayy
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Trang 11
288005 (SOENCENOMICOURTESVOTSEAN CONNELL: SENCE CAREERS COMSTOCK Kelp wanted SCIENCENOW wwm.sciencenow.org DAY NEW
In the Deep, a Tropical Surprise
Kelp forests may exist throughout the tropics, a new study finds Space Germs Could Yield Earthly Cures
Taking bacteria on a shuttle ride reveals some of their best-kept secrets
'0VERAGE
Twinkle, Twinkle, Lonely Stars
Astronomers discover a stellar hatchery far outside 2 galaxy’s main body
Day length influences behavior
SCIENCE'S STKE "
wWWfstk€.org, SIGNAL TRANSDUCTION KNOWLEDGE ENVIRONMENT
PERSPECTIVE: Gene-Hormone-Environment Interactions in the Regulation of Aggressive Responses: Elegant Analysis of Complex Behavior
D Pfaff and R Silver
The effects of estragen on behavior are modulated by day lenath PROTOCOL: Studying Integrin-Mediated Cell Adhesion at the Single-Molecule Level Using AFM Force Spectroscopy GM Fronz, A Taubenberger, P-H Puech, D.) Muller Forces between adhesion receptors and their ligands can now be measured atthe level of single molecules, GLOSSARY Find out what Smo, Ptc, and Gas mean inthe world of «ellsignating Do you have the Aaller instinct? SCIENCE CAREERS Wun sciencecareers.org,
AREER RESOURCES FOR SCIENTIST
US: Tooting Up—The Killer instinct: Rarely Taught in Academia, But Fostered in Industry
D Jensen
Industry employers relish the kilerinstinc in scientists
GLOBAL: Mastering Your Ph.D.—Progress Reviews With Impact
8 Noordam and P Gosting
Here are some tps for getting a progress review with the answers and a plan you need
MMISCINET: Educated Woman, Postdoc Edition, Chapter 9— The Postdoc Has Two Faces
MP DeWhyse
‘Micella attempt to figure out how to make i through, the next2 monthswithout her head spitting
US: From the Archives—Writing a Research Plan J Austin
Writing an effective research plan isan important part of your development asa scientist
SCIENCEPODCAST
Download the 28 September Science Podcast to hear about clues to wasp eusociality, ancient Polynesian trading, and the winners of this year’s Science and Engineering
isvalization Challeng
mmesroncemag.org/abou/paccas atl
‘Separate individual or institutional subscriptions to these products may be required for full-text access
Trang 124c
Gain To American Association Upcoming AACR Meetings
and Conferences
Join the world’s leading cancer researchers for the latest findings
and most important scientific advances at these conference:
October 31-November 3, 2007
The Role of Non-Coding RNAs in Cancer Philip A Sharp, René Bemards, and Todd R Golub, Chairpersons
Cambridge, Massachusetts November 4-8, 2007
AACR Centennial Conference:
Translational Cancer Medicine: Technologies to Treatment
Edison T Liu and William N Hait, Chairpersons, Singapore
November 14-17, 2007
Advances in Colon Cancer Research Monica M Bertagnolli, Hans Clevers, and Raymond N DuBois, Chairpersons Cambridge, Massachusetts November 27-30, 2007
The Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved In conjunction with the AACR Minorities in Cancer Research Council John D Carpten, Timothy R Rebbeck, and Olufunmilayo I Olopade, Program Committee Chairpersons Atlanta, Georgia December 5-8, 2007
6th Annual International Conference on Frontiers in Cancer Prevention Research Andrew J, Dannenberg, Program Committee Chairperson elphia, Pennsylvania December 6:9, 2007 The Role of Telomeres and Telomerase in Cancer Research
Maria A Blasco, Woodring E Wright, and Virginia A Zakian, Chaitpersons
San Francisco, California January 22-25, 2008
Ubiquitin and Cancer: From Molecular Targets and Mechanisms to the Clinic Claudio Joazeiro, Tony Hunter, and
Kenneth C Anderson, Chaimpersons San Diego, California
February 3-5, 2008 Cytoskeleton Signaling in Cancer Rakesh Kumar and Alan Hall, Chairpersons San Diego, California
February 12-15, 2008
The Role of Cancer Stem Cells in the Initiation and Propagation of Tumorigenesis
John E Dick and Jane Visvader, Chairpersons Los Angeles, California
February 24-26, 2008,
Energy Balance and Cancer: Mediators and Mechanisms Joint AACR: Transcscilinary Research on Energetics and Cancer (TREC) Conference Nathan A Berger, John D Potter, Kathryn H Schmit, and Cornelia M Ulich, Chaitpersons
Lansdowne, Virginia March 15-18, 2008
‘Advances in Cancer Research: From the Laboratory to the Clinic Samir N Khleif, Chairperson
Dead Sea, Jordan April 12-16, 2008 ‘AACR Annual Meeting
Eileen P, White, Program Committee Chairperson San Diego, California
May 20-23, 2008
Candidate Pathways, Whole Genome Scans: Reconciling Results, Looking into the Future
In conjunction with the Molecular Epidemiology Working Group of the AACR
Coxnelia M Ulrich and Stephen Chanack, Chairpersons Carefree, Arizona May 28:31, 2008 Cancer Epigenetics Jean-Pierre Issa and Peter W Laird, Chairpersons Boston, Massachusetts July 21-24, 2008
‘AACR Centennial Conference: Translational Cancer Medicine Chairperson TBD Monterey, California
August 3-7, 2008
Joint Metastasis Research Society-AACR Conference on Metastasis
Danny R Welch, Chairperson Vancouver, British Columbia, Canada
Fall, 2008
‘Omics to Clinics: Translation of Cancer Genome Insight Into Therapeutics and Diagnostics
tynda Chin, Joe W Gray, William R Sellers, and Richard L Schilsky, Chairpersons
Location TBA
October 13-17, 2008 Chemical and Bi
Inflammation and Cancer Michael Karin, Lisa M Coussens, and Lawrence J Mamet, Chairpersons Ko Olina, Oahu, Hawaii
October 21-24, 2008
EORTC-NCI-AACR International Conference on Molecular Targets and Cancer Therapeutics
Patrick Schafiski, James H Doroshow, and Eric H Rubin, Scientific Committee Chaitpersons Geneva, Switzerland
November 3-6, 2008
‘AACR Centennial Conference: Impact of Emerging Technologies on Cancer Diagnosis and Therapeutics ‘Michael 8 Kastan, Joseph D Rosenblatt, and Moshe Oren, Chairpersons Jerusalem, trael November 11-14, 2008 Targeting the PI3-Kinase Pathway in Cancer Prevention Lewis C Cantley and Charles L Sawyers, Chairpersons Cambridge, Massachusetts November 16-19, 2008
‘Seventh Annual International Conference on Frontiers in Cancer Prevention Research Chairperson TBD
Washington, DC
December 25, 2008 Tumor Immunology Louis M, Weiner, Olvera J Finn, Alexander M M Eggermont, and Dmity | Gabrlovich, Chairpersons Miami, Florida
December 5-7, 2008
Trang 13RE: EDITED BY STELLA HURTLEY AND PHIL SZUROMI ce.-
When Quantum Arithmetic
Doesn't Add Up
If you add an item to your shopping basket and then remove one that is identical, your total bill does not change If you shop in a quantum supermarket, however, the probabilities and the sequence of adding or subtract ng to your shopping basket matter and can change the total Parigi et al (p 1890; see the Perspective by Boyd et al.) demonstrate this counterintuitive behavior for pho- tons in a light field Adding or subtracting a single photon to or froma light field produces a different result depend- ing on the sequence of the event, with the final state of light field being different from the initial one This capa- bility of engineering the quantum state of a light may
prove useful in areas such as quantum communication
Fluorinated Drugs
on the Rise
Organofluorine substituents are playing an increasingly important rolein synthetic small ‘molecule pharmaceuticals, including such major drugsas Lipitor and Prozac In a review, Miller et al (p 1881) highlight the emerging understand- ing of how fluorine interacts with proteins during docking events Elucidation of these itermolecu- lar interactions complements more traditional paradigms of fluorine’s electron-aithdrawing effects, which influence substrate basicity, and its wide-ranging stereoelectronic impact (on substrate conformation The discussion is supported by analysis gleaned from exten- sive searches of structural databases
Quantum Noise
Reduction
Asuccessful quantum computer must over- come decoherence effects caused by interac- tions with its environment Such effects could be
mitigated if they fully characterized, which in principle can be done by process tomography However, this process requires resources that «grow exponentially with the number of qubits in the system, which renders it impractical Emerson et a (p 1893; see the Perspective by Bacon) describe a theoretical technique through which key features of the decoherence can be effi ciently measured, which reduces the number of experiments from exponential to polynomial The authors present an experimental implemen- tation of the method on quantum-information
www.sciencemag.org
processors based on liquid-state and solid-state nuclear magnetic resonance methods
Up in the Air
Widespread free oxygen is thought to have evolved in Earth’s atmosphere only after about 2.4 billion years ago Candidates for the cause of increase include dynamic effects in the planet's interior, escape of hydrogen, or the evolution of ‘cyanobacteria Anbar etal (p.1903) and Kaufman et al (p 1900) examined the geochemistry of a detailed section obtained in a drill
core through the Mount McRae Shale, Western Australia, dated to about 2.5 billion years ago They used trace ele- ment chemistry (partic- ularly of molybdenum and rhenium, which respond to oxidative weathering) and the mass- independent fractionation of sulfur isotopes (hich can indicate the lack of abundant ozone) to trace the presence of free oxygen The data indi- cate the first hints of atmospheric oxygen, but still at low levels, at this time
Seen On Edge
Ina rare alignment, the plane of Uranus’ rings appeared edge-on to Earth in August 2007 This
unusual configuration reveals the unlit side of SCIENCE VOL317 28SEPTEMBER 2007
the rings, including faint rings that are bright- ened by scattered light With the Keck telescope in Hawaii, de Pater et al (p 1888, published online 23 August) snapped an infrared picture of the side-on rings Diffuse dust envelops the entire ring system but is unconnected with any particular ring or feature The pattern of dust has changed significantly since the rings were first photographed by the Voyager spacecraft in
1986, which indicates that such changes are common in the solar system and occur on much larger scales than had been expected
Spin, All Together Now
Manipulation of the spin of an electron in a sin- gle quantum dot isa strong contender for quan- tum-information processing protocols However, the spin dynamics of each dot depend strongly ‘on environment, and the distribution resulting from dot-to-dot variability presents a formidable problem in addressing a system with many quantum dots Greilich et al (p 1896) report cn femtosecond magneto-optical pump-probe experiments on an ensemble of self-assembled semiconductor quantum dats A sequence of laser pulses can induce al ofthe electronic spins across the ensemble to precess coherently As the spin information is stored in the nuclear spin, this process effectively results in a long-term memory for the electronic phase information
Hawaiian Getaways
Some Polynesian legends describe voyages from Hawai'i back to other Polynesian islands, but
Continued on page 1831
Trang 14ntl cDNA Syn
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Trang 15This Week
Continued rom page 1829
evidence for these return trips has been lacking Collerson and Weisler (p 1907; see the Perspec- tive by Finney) have examined the chemistry of 19 basalt adzes collected on a coral atoll in the Tuamotus to trace their origin The data link many of the adzes to nearby islands, but the isotope and trace element chemistry uniquely links one to Hawai‘, 3400 kilometers away Thus, the Polynesians had a maritime trade network extending over thousands of kilometers and some repeated contact, with Hawai’,
Viral Pesticide Resistance
Although insect resistance to chemical agents is well documented, there is little information on virus insecticides Generally, these have been considered safe reagents, with little prospect of resistance developing in the host; however, resistance to the codling moth granulovirus has been observed in field populations Asser-Kaiser et al (p 1916) now show that the resistance factor is a Zsex-linked feature After selection, a population was isolated that was 10,000- to 100,000-fold more resistant to the virus challenge, which is considerably higher than the naturally resistant field strains
Giving the Brain a
Magnetic Massage
Transcranial magnetic stimulation (TMS) is an increasingly ‘common technique used to selectively modify neural process- ing, Although TMS reportedly alters neural and hemodynamic activity, basic neurophysiological evidence for these effects is largely unexplored Allen et al (p 1918; see the news story by Miller) applied TMS to anesthetized cats while measuring neural and hemodynamic activity simultaneously in a co-localized region of the neocortex, and provide quantitative data on the neural effects of TMS and how they relate to standard neuro imaging techniques These results also provide insight into the ‘mechanisms of brain plasticity that are thought to underlie long-lasting therapeutic effects of TMS
Parasitic Evolutionary Oddity
Giardia is a common intestinal protozoan parasite and an important human disease agent Morrison et al (p 1921; see the Perspective by Keeling) offer a genome analysis of Giardia that reveals a wealth of unusual attributes, including an extremely simplified metabolic capacity relating to its parasitic life-style; little DNA heterozygosity in a cell thought to lack a sexual cycle; functionally enigmatic amino acid insertions in otherwise conserved regions of proteins; an unusual actin cytoskeleton that lacks conventional myosin; and simplified DNA replication and RNA processing machinery
Mammoth Mitochondrial Sequencing Effort
Ancient DNA survives well in hair, is found in copious quantities in cold environments, and can be decontaminated easily Gilbert et al (p 1927) used these advantages to completely sequence the mitochondrial genomes of 13 Siberian woolly mammoths One of the samples came from the Adams
mammoth, which was found in 1799 and has been stored at ambient temperatures for the last 200 years This finding will facilitate analysis of samples of organisms that can only be found in museums
Sulfated Tyrosine and HIV Entry
In order for human immunodeficiency virus type 1 (HIV-1) to enter host cells, its envelope glycopro- tein gp120 must bind to the host-cell surface receptor CD4 and to a co-receptor An unusual post- translational modification, tyrosine sulfation, is important to the co-receptor interaction Huang et al (p 1930) have investigated HIV-1 gp120 interactions with a sulfated N-terminal peptide from the co-receptor CCRS and determined the crystal structure of a tyrosine-sulfated antibody in complex with gp120 and CD4 A conserved site in gp120 recognizes sulfo-tyrosine and might be a target for design
of therapet
AAAS Travels
Come explore the world
with AAAS this year You will
discover excellent itineraries
and leaders, and congenial groups of like-minded travelers Who share a love of learning and discovery Sea of Cortez December 10-17, 2007 Voyage to Baja Califor
Sea of Cortez on board the Explore “Mexico's Galapagos, fascinating wilderness islands abundant sea life, $2,820 + ai"
Costa Rica December 23- January 1, 2008 njoy an introduction over the
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toactive voleanoes, monke; sloths, macaws & more! ESE $2,695 + ai
Chile January 16-31, 2008 & Easter Island
Discover Chile from Santiago to the spectacular Patagonian fjords and legendary Easter Island! On board
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India Wildlife Safari
January 20- February 3,2008 $Ÿ“ Dy
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duction to the national parks, a
sanctuaries, and exquisite cultural
antiquities of India, from tigers to the ‘Taj Mahal, including three premiere Hm national parks a Undiscovered West Airica February 13-23, 2008
Explore the treasures of Senegal and The Gambia, on board the 34-passenger yacht, Callisto See
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Trang 17‘CREOMS TOP To KOTTOM VOLKER STEGER UPR MAGES Tim Huntis a principal scientist at Cancer Research UK, Clare Hall Laboratories, South Mims, UK E-mai tim.hunt@ cancer.org.uk
European Young Investigators
SCIENCE IS INTERNATIONAL, BUT ITS FUNDING AND ADMINISTRATION ARE USUALLY A ‘matter for governments of nation states In Europe, this balkanization leads to problems; perhaps the worstis finding peer reviewers when, in a small country, applicants for support may have few peers Of course, the definition of “peer"is not always clear, and it can be difficult to identify real experts ina field unless oneis init That creates a problem, because supporting anything less than superior research wastes taxpayers’ money Ina small country, identifying quality depends on the fair and accurate opinions of foreign experts
Having dealt successfully with this problem, a Europe-wide collaboration to fund basic research through a program called the European Young Investigators ((EURY 1); wwwesfon/ activities/euryi.htm!] has sent four cohorts of outstanding young European scientists into their posts with substantial research support since 2004, For better or worse, that program, which sup- ported research ranging from theoretical physics to sociology, made its final
appointments this year The good news is that almost 100 investigators got grants of up to 250,000 euros per year for 5 years with no strings attached ‘An important question now is whether the European Research Council (ERC) will manage a similar program (Young Investigator Programme) with the same attention to the freedom and independence of young investigators that became a hallmark of EURYI
‘The EURY I scheme was hatched by a roster of research councils from all over Europe, encouraged and administered by the European Science Foundation, Heads of the research councils wanted to promote European, rather than national, science and were concerned about career structures in the European Research Area EURYI arrived when the Framework Programmes of the European Union (EU) were already in place, but the latter were not intended to support basic research, Rather, the EU awards are
contracts, not grants, with milestones and deliverables that are more appropriate to engineering projects than to the foggy uncertainties of basic research, And European scientists have long complained about the application paperwork required for EU support Really, the only mystery is why it took so long to set up a simple grant scheme such as EURY Ito support young scientists
A suecessful EURY l awardee had typically made an important discovery asa graduate student, ‘made another as a postdoctoral fellow abroad, often in the United States, and then returned to Europe to set up a thriving laboratory I chaired the Life Sciences and Medical Sciences selection process during EURYI'S4 years and was very heartened by what | saw: administrators, panelist candidates, and their institutions all enthusiastically supporting the program's mission and
ous review by national and international panels), no matter where they came from, success was quickly evident from the growth of the award’s prestige, the increase in the mutual trust of the participating organizations, and the scientific contributions ofthe EURY scholars Countries entered and left the program, some disappointed by their lack of success, but it was important—and a surprise—that there was no “juste retour” in the EURYI scheme A nation could submit candidates for consideration in proportion to its financial contribution, but there was no guarantee that any of them would be succes
Trang 18EDITED BY GILBERT CHIN AND JAKE YESTON
‘The 100,000 or so ships that make up the global commercial and military fleet collectively travel billions of vessel-miles every year, producing a large fraction of the pollution contributed by fossil fuel burning in the transportation sector In addition to the direct radiative effects oftheir emissions, caused by the light-scattering properties of the particles themselves, aerosols from the exhaust plumes can produce thin lines of very low clouds in the marine boundary layer, an example of the aerosol indirect effect It has been shown that the local effects of these clouds can be large, up to 100 Wim? (for comparison, the average solar {lux at the top of the atmosphere is about 340 Wim), but how large an influence they exert on the global albedo has been an unresolved concem Schreier et a analyzed a full year of satellite data derived from ENVISAT AATSR (Environmental Satellite ‘Advanced Along-Track Scanning Radiometer) in order to estimate the size of the radiative forcing caused by ship tracks They found that, contrary to fears arising from previous global model estimates, the global annual mean radiative forcing from ship ‘racks was small, 0.4 to 0.6 mWWim2, and negligible compared to estimates of total net anthropogenic radiative forcing, 0.6 to 2.4 Wim? Thus, it seems that ship tracks are too inconsequential to affect the rate of anthropogenic global warming — HJS MOLECULAR BIOLOGY
Regulation Revealed Under Stress In most eukaryotic genes, the protein-coding
sequences are interrupted by noncoding introns These introns are removed from the pre-mRNA transcript by RNA splicing, a process that pro- vides an additional and sometimes critical layer of gene regulation Unlike more complex organ isms, few genes in the yeast Saccharomyces cerevisiae contain introns In those that do, the splice site sequences often conform to a strict consensus, making it unlikely that the use of alternative splice sites figures in the differential expression of genes Intriguingly, though, ribo- somal protein genes (RPGs)—components of the mRNA translation machinery—are the largest class of intron-containing genes
Pleiss et al show that amino acid starvation, which induces a general repression of transla~ tion, also results in a rapid and specific reduc tion in the splicing efficiency of nearly all intron-containing RPG transcripts Thisis not merely an effect of stressful circumstances, because exposure to high levels of ethanol does not have an effect on RPG splicing; rather the splicing of distinct sets of transcripts is either down- or up-regulated The yet-to-be-discovered regulatory mechanisms, which other evidence suggests could be mediated by core, rather than accessory, spliceosomal components, probably explain the evolutionary retention of intron these groups of yeast genes and, given the con-
1834 28 SEPTEMBER 2007 VOL317 SCIENCE
servation of the RNA splicing machinery, similar mechanisms may pervade pre-mRNA splicing in higher eukaryotes — GR ‘Mol, Cell 27, 10.1016/.molcel.2007.07.018 (2007) CHEMISTRY
A Hot Dip Before Swimming
‘Most solution routes for nanoparticle synthesis proceed in nonpolar solvents and achieve size
selectivity in part by capping the surfaces with hydrophobic groups However, after this prepara- tion, many applications require dispersing the nanoparticles in aqueous solvents Ligand exchange reactions can be used to introduce ‘capping agents that bear hydrophilic ‘groups on their ends, but these ® reactions, which often run
near room temperature, tend to be incomplete, ‘and can lead to aggre- gation if ligand des- ‘orption dominates, and exposes the tundertying surfaces Zhanget al have devel-
‘oped a robust method for >
exchanging hydrophobic cap- ping groups with short-chain
polyelectrolytes such as polyacrylic acid) run in polar solvent such as
to &
Geophys, Res ett 34, 117814 (2007)
~245°O) The multivalent polyelectrolytes help displace the hydrophobic ligands while minimiz- ing surface exposure The properties of several nanoparticles —magnetism for iron oxides, photo- catalysis for titanium dioxide, and photolumines- cence for cadmium setenide—ere maintained or even improved after such processing — PDS
‘Nano Le 7, 10.1021/nl0719281 (2007)
puvsics
Stimulated Symmetry
Whereas the underlying parameters of condensed matter systems may be fixed, thereby limiting the pphase space in which to vary the material proper- ties, the ability to tune and manipulate atoms or ‘molecules trapped in an optical latice opens up that phase space With success demonstrated already in systems with isotropic symmetry,
asin the case ofthe superfluid-to-Mott- ‘insulator transition of bosons on a
square lattice, interest is now in 2 describing systems with an = anisotropic symmetry in the order
Trang 19tice, resulting in a d-vave momentum distribu- tion The proposed scenario offers the prospect of engineering optical latices for the modeling of complex interacting phenomena rơm the likes of
high-temperature superconductivity to magnetic frustration — 150
Phys Rev Lett 9, 113002 (2007)
BIOCHEMISTRY
Acquiring a Trace Element
Iron, asthe central element in heme cofactors or as part of metal clusters, endows enzymes with the capacity to carry out a much wider range of redox reactions (such as those in respiration and photo- synthesis) than is supported by the functional ‘groups of the genetically encoded amino acids Hence, the acquisition of iron isa highly comps tive endeavor, and as ocean supplementation experiments have shown, iron can be a limiting ‘nutrient forthe growth of plankton Nevertheless, ‘marine organisms face a special challenge because iron in an aqueous and aerobic environ-
CHOI
ment of neutral pH i present mostly in insoluble forms The bacterial solution has been the manu facture and secretion of siderophores, small mole cules that chelate Fe(l Following on their previ- us identification of a borate-siderophore interac- tion, Harris etal provide a fuller characterization of the equilibria inthe reaction of B(OH), and vib-
rioferrin, a siderophore of Marinobacter spp The tetrahedral coordination of B(I) by the pair of ơ-hydroxycarboxyate moieties in vibrioferin is highty pH-dependent, and accounting for the pro- tons contributed by the hydroxys as well as one donated by solvent allowed the authors to assem- ble the formal binding constants for the multiple borate-vibrioferrin complexes Extending this analysis to the other two types of siderophores— the catecholates and the hydroxamates—revealed thatthe former are also competent to bind boron ‘whereas the later are not Whether any of these
capabilities are in fact used by the siderophore producers is as yet unclear, though low-pH envi- ronments may be one place to look — GIC
An, Cher Soc 129, 10.1021/a073788x (2007)
<< Preventing Transformation
The oncogene c-Myc, which encodes a transcription factor, is well known for its ability to transform cells, However, not al cells are equally sensitive to c-Myc~induced transformation Partanen et al compared the responses of organized epithelial
2 acini and of disorganized or imma- ture acini formed from mammary epithelial cells to the trans- forming ability of a form of c-Myc (MycER™) activated by cell exposure to tamoxifen When epithelial cells were plated in Matrigel (a three-dimensional cell culture environment pre- pared from an extract of extracellular matrix) and MycER!™ was activated right away, the cells formed misshapen acini and some cells could be seen in the luminal space On the other hand, cells grown in the absence of activated c-Myc formed symmetri- cal acini with an empty lumen, and the acini were smaller If tamoxifen was added after the cells had already formed organ- ized acinar structures, then c-Myc lost ts oncogenic activity: The morphology and size of the acini were unchanged, and cell pro- liferation was not induced Cells in which the kinase LKB1 (implicated in the establishment of cellular polarity) was silenced formed disorganized acini with disrupted cell potarity when cultured in Matrigel However, these LKB1-deficient cells did become quiescent Activation of c-Myc in the LKB1-deficient cells stimulated reentry into the cell cycle, thus confirming the potency of epithelial organization as a brake for oncogenic transformation The authors also addressed the apoptotic active ity of Myc, which sensitized cells of fully organized acini to TRAIL (a death-inducing agent that activates apoptosis) and
revealed that both TRAIL and Myc were required to promote apoptosis However, in LKB1-deicient cells with disorganized acini or immature acini, the activation of MycER™ or TRAIL caused apoptosis, and these two agents had an additive effect on cell death Thus, disorganized epithelia are more sensitive to both the cell-proferative and apoptotic effects of c-Myc — NRG
Proc Natl Acad Sci U.S.A 104, 14694 (2007) Amazingly comfortable operation Simple “One-step’ commandbuttons, just clíc (G101 cata error 0h sd
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ere cence@sciencemt <a) coments maaan ‘one dH SIGE: sewon oneness Favenap Ugpenbridc seo conoxs Caroline Bs, Stla Mt Hurley, lan ‘rbot, Stephen | Simpson, Peer Sen aiocat te Joanne ‘Baker: eona supont Deborah Denton, Rachel Roberts, Ale Whale aamusearvesuvoe)anet Clements, el Wit; wos ere ‘us toe) Tavis 200 xa toa Di {CEfy cơưendmae Cancsrowes Michael Bale (ar), John Bohannon (Vienna, Moran nse Gnsteeam and Fan, Gece Voge (Bei)
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‘AAAS Bows í Dtdok sta reson, ce ola Helden: ‘este Dari fsttmere meson Jmes) MeCahy; masse David sho; outs eacomweorealan | Lesh aaua John E Dowling, inn W Enq Susan Fhaptick Re Gat Unde eh Chery Mary Thomas, Pale, Kathy Slvan MVAAAS ADVANCING SCIENCE, SERVING SOCIETY eae gtr moe Geert Stall, Coase iatin TH eae ee = Eons ee eae
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Trang 21
r E 7 - Applied Biosystems SOLiD'" System
Trang 22
ARE YOU A PIONEER? Now recruiting master teachers and scientists faculty for Fall 2009 For further details on specific
openings and application instructions please call 1-866-218-6003 or contact rmd@nepamedc.org
thecommonwealthmedical.com | The link to the Dean's blog is newmedicalschool blogspot.com THE COMMONWEALTH MEDICAL COLLEGE
Trang 23Don’t Be Lat
you're itching to visit other stars, better zip cover to London first On 15 November, the
British interplanetary Society (BI) will host a ‘workshop titled “Warp Drive, Faster Than Light: Breaking the Interstellar Distance Barter.”
“Warp” refers to the fact that space and time can bend, stretch, and shrink The confer-
ence is based on work by theoretical physicist Miguel Alcubierre, now at the National
‘Autonomous University of Mexico in Mexico Gity, who in 1994 showed that Einstein’s gen- eral theory of relativity, which equates gravity with the bending of space and time, could allow for faster-than-light propulsion He noted that because the universe is expanding, two distant galaxies can move apart faster than light with- out either one’s moving that fast relative to the space around it Run the film backward, and the galaxies rush toward each other Combining the effects, Alcubierre showed that in theory, one could move a patch of ordinary space superfast by shrinking space in front of it and stretching space behind it to make a “warp bubble.”
There's a hitch, however The scheme requires "negative energy,” which does not exist as far as anyone knows “The idea was to make a fine point about general relativity, not really to have any practical means of traveling faster than light,” says Alcubierre, who will not attend the conference Physicist Richard Taylor, a con- sultant to BIS, saysit's till “quite exciting to let real scientists talk about things that are almost off-limits.”
AJuicy Match
Following up on an intriguing clue from Vietnam, researchers in Florida are studying ‘whether guava trees can control a devastating plant disease called citrus greening Spread by aphidlike insects called psyllids, the bacterial disease makes fruit taste nasty and then kills trees Itwas first spotted in Florida 2 years ago, but citrus growers have yet to figure out how to beat it (Science, 28 April 2006, p 523)
U.S Department of Agriculture (USDA) researchers recently leamed that in Vietnam, orange groves planted with guava trees were disease-free So they went to look for them- selves “It was pretty much incredible,” says
wewwsciencemag.org
ON
li VÌ
EDITED BY CONSTANCE HOLDEN
When you think of an invasive species, the freshwater jellyfish Craspedacusta sowerbyi (above) probably
twhat comes to mind But the Chinese native has a firm tentacle-hold in the United States and now
s from coast to coast
To find out more about this and other aquatic interlopers, visit the Nisbase Web site from the Smithsonian Environmental Research Center in Edgewater, Maryland The site allows you to simultaneously scan nine databases that cover areas as far apart as the Gulf of Mexico, the Mediterranean Sea, and Australia There are links to images, fact sheets, museum records, and species accounts from the taxonomy hub ITIS C sowerbyi, you can learn, probably hitched a ride to the United States in ornamental water plants shipped from the Yangtze River valley >
wupl,nisbase.0rd
entomologist David Hall, I never found a psyl- lid in the interplanted fields.” The USDA team is ‘now planting some 10,000 guava saplings in test orchards Hall says it will take atleast a year tosee if these guava varieties, different from those in Vietnam, ward off psllids in Florida ‘orange trees, which are not planted as densely as they are in Vietnam Denise Feiber, a spokesperson for the Florida Department of Agriculture, says she's cautiously optimistic but points out that guava trees attract fruit flies, which could complicate the pic- ture, Ultimately, the scientists say, compounds from guava extracts might be used as sprays
Disappearing
Tongues
Of 6900 languages spoken in the world today, 6300 are in danger of going extinct, say two linguists who have mapped the world's “language hot spots.”
Gregory Anderson and K David Harrison, a Visiting professor at Swarthmore College in
SCIENCE VOL317 28SEPTEMBER 2007
Pennsylvania, have taken the concept of “bÍo- diversity hot spots” and applied it to languages, using criteria that include "genetic diversity”: the ratio of languages to language families Bolivia, for example, has as many language lineages as Europe but far fewer languages, which means its language diversity is threatened Other hot spots are in North America, Siberia, and Australia
The pair, who are documenting languages with high-tech equipment
from the National Geographic Society, have just returned from northern Australia, whose 231 aboriginal
languages—trom 50 different language families—are almost all endangered They found a lone speaker of Amurdag, a lan- ‘guage that had been thought extinct, and three known speakers each of two other languages, Magati Ke and Yawuru
rw
“Old Man" Patrick Nanudjul, one of the last three speakers of Magati Ke
Trang 24Antiangiogenesis ate ten in Therapeutic _ Development — =-
This the premier conference The conference focused on the ost Up wil feature
date sientfcand cna New veatment ages advancesbengmadeinthe " Neyaeatnen angigeness eos well 95 « Cineal deseopment inthecincal ansationo! "Grates angogenessinhibtors in « Regulatory and payer oncology Wehve adst- —" petgeces Inguished faculty of experts « Vacs seneation in
from academia, government” yngiogeness dug andindwy nduing MÌT _ doogmel Profesor Robert Hortz, «Soma, surogates, Nobellaurestein Medcine ` mớmmabungcvoodie ors,
Who should attend
‘Academic and industry researchers, clinicians, biopharma- ceutical executives, and government and advocacy leaders
To learn more and to ret THEANGIOGENESIS pry 70 80382111 contri, ma 02238 FOONDATIONMMME 6175765708 (6175765808, Drug Development Resources for the Academic! Not-for-Profit Investigator
On a competitive basis, the NIH offers certain critical resources needed for the development of new small molecule therapeutic agents The NIH-RAID Pilot is nota grant program Successful projects will gain access to the govemment’s contract resources Se include: Synthesis in bulk of small molecules
is of oligonucleotides; Chemical synthesis of s; Scale-up production; Development of
analytical methods; Isolation and purification of natural products; Pharmacokinetic/ ADME studies including bioanalytical method development; Development of suitable formulations; Manufacture of phase I drug supplies; Range-finding initial toxicology; IND- directed toxicology; Product development planning and advice in IND preparation The program also is open to non-U.S applicants
Applications are received electronically through
Grants.gov Ideas arising solely from a corporate source without academic collaborators are not eligible
NIH-RAID Pilot Program Office & @ 301-594-4660; nih-raid@mai ov fail URL: http://nihroadmap.nih.gov/raid — (Q>)OPASI scence News Nf nei THis WK sos Sees ow vst Net Bi Scot scenes sum q - Science apres Brides pod NI ot print Ấn hen otieation ‘Sciencenow Daly Att Baty headline summary
‘Science Magazine TOC Weeliy table of contents
This Weekin Science ‘Summaries of research san
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Get daily and weekly E-alerts on the latest breaking news and research!
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sreroc allfrom your e-mail inbox To start
Trang 25‘CREOMS TOP TO BOTTOM LA FERIA: CAROLE NFRD, SOURCE: CHLOE LEGRS
The first World Conference on Research Integrity drew 300 people from 52 coun- tries last week to Lisbon, Portugal Science caught up with one of its organiz~ ers, Nicholas Steneck of the US Office of Research Integrity, which joined with the European Science Foundation to initi- ate the event
Q: Did the conference achieve what you wanted?
My expectations changed significantly ‘over time I had overestimated the level of engagement [on this issue] in many other countries, and therefore we had to back up and do more basic education From that perspective, I'm enormously pleased
Q: One speaker called plagiarism a “vic- timless crime.” Were you disappointed by that?
Raising that question is important 1 have often said that plagiarism may have a positive outcome because it still spreads scientific information We really do need to assess which behaviors are having the biggest impact on research integrity
Q: Norway has established a very formal scientific misconduct system with an appointed judge Do we need a World Court of Research Integrity?
The solutions have to be country- appropriate What is important is [to] ‘establish minimum standards: There must beaplace to report, there has to ben able assurance an investigation will take place, and] there has to be anonymity or at least protection of whistleblowers
TWO CULTURES
WANTTO TRY IT? After 3 years and 100 hours of tape, Richard Rifkind, chair emeritus of the Sloan-Kettering Institute
for cancer research in New York City, is wrap-
ping up a documentary
on how science really
gets done The Lab chronicles the attempts of graduate student Robert Towntey to uncover the atomic structure of AMP- activated protein kinase
in Lawrence Shapiro's protein crystallography lab at Columbia University
Rifkind, a cancer researcher who helped develop the lymphoma drug Zotinza, wanted to portray an important scientific challenge that also would look nice on film in his quest
to educate the public about the true process of scientific discovery Townley didn't pull any punches, either, says Rifkind: ‘At one point, he looks at the camera and says,
Got a tip for this page? E-mail people@aaas.om
INAV VN EDITED BY YUDHIJIT BHATTACHARJEE
“Two-and-a-half more years of misery.’ ” The film is co-produced with Rifkind’s wife, Carole, and incorporates a video diary that Townley had been independently keep- ing for several years The Rifkinds are in talks with several broadcasters for release rights The couple's first film, released in 2005, documented the effects of tourism on Venice
THEY SAID IT
“T propose the following character sequence for
joke markers: :-) Read it
sideways.”
—Scott Fahlman, inventing the first emoticon in a message he posted on an electronic bulletin board 25 years ago Fahlman, a computer scien- tist at Carnegie Mellon University in Pittsburgh, Pennsylvania, and his colleagues last week started an annual $500 Smiley Award student Contest to foster innovation in technology assisted person-to-person communication UGHTS OUT Darkness has fallen over a sliver of
easter Canada, and astronomers are thanking Chloé Legris for it The 32-year-old engineer at the Mont-Mégantic Observatory in eastern Quebec province took the lead in persuading federal, provin- cial, and municipal governments to limit light pollu- es around the observatory Her st reserve recognized by the I Datk-Sky Association All of the sky- polluting light fixtures within 25 kilometers of the observatory have been replaced with shaded models that do not project light upward, in the first step of a process that will eventually include neighboring Sherbrooke, a city of 150,000 residents
‘The measures should reduce light pollution to the levels last seen 30 years ago, says Robert Lamontagne, director of the observatory The increased level of light pollution, he says, had “shrunk” the observatory’s 1.6-meter telescope to the point at which “there was some research we couldn't do anymore.” Legris says public officials saw the light after she explained that replacing 2500 light fixtures with astro-friendly designs would
Trang 261842 INFECTIOUS DISEASE What a magnetic field does to the brain
Vaccine-Related Polio Outbreak
In Nigeria Raises Concerns
Northern Nigeria has been hit by one of the largest known outbreaks of poliomyelitis, caused by the live polio vaccine itself The ‘ongoing outbreak could be a serious setback for the global polio eradication campaign: It is occurring in a region where rumors about vaccine safety derailed vaccination efforts
several years ago
Experts with the Global Polio Eradication Initiative emphasize that the widely used trivalent oral polio vaccine (OPV) is safe But the low immunization rates in northern Nigeria have created the conditions for the attenuated vaccine virus to regain its viru- lence and trigger an outbreak
Detected in September 2006, the outbreak of vaccine-derived poliovirus (VDPV) type 2 ‘was immediately reported to the World Health Organization and Nigerian health officials But the informationis just now beingreteased pub- licly—in the 28 September Morbidity and Mortality Weekly Report and WHO's Weekly Epidemiological Record—a delay that has caused some consternation in the polio com- ‘munity Officials say they were worried that the news, if misconstrued, could again disrupt polio vaccination efforts in Nigeria,
“There were legitimate concerns that anti-polio vaccination rumors would be rekin- dled by an incomplete explanation of the cause of the VDPV outbreak,” says Olen Kew, who has led efforts to analyze the outbreak from the
28 SEPTEMBER 2007 VOL317 SCIENCE
US Centers for Disease Control and Preven- tion in Atlanta, Georgia
Several polio experts told Science that although they understand how sensitive the sit- uation is, they disagree with the decision to keep quiet.“ am troubled that the information hasn't come out, absolutely.” says Donald A Henderson of the University of Pittsburgh Center for Biosecurity in Baltimore, Maryland Henderson says details of each outbrc cessential ifscientists are to understand just how risky these vaccine-derived strains are
So far, there are 69 confirmed cases of paralysis, and more suspected, caused by VDPV in nine northern Nigeria states, says Kew The case count seems certain to rise About half the cases have occurred around Kano,a largely Muslim state where anti-Westem sentiment and rumors that the vaccine caused sterility or AIDS led several states to halt polio vaccination in 2003 After repeated demonstra- tions of the vaccine’s safety and considerable bhind-the-scenes diplomacy, vaccinations resumed about a year later, but the damage ha already been done
By the end of 2004, the number of polio ria had doubled to about 800, and in 2006 it soared to more than 1100 Wild virus from Nigeria reinfected some 20 other coun tries, leading toa spike in global cases It was a huge setback to the Global Polio Eradication Initiative, which estimates that the world spent "U17 ) Cree)
Double whammy Northern Nigeria is batting wild and vaccine-derived poliovirus
an additional $500 million to contain the dam- e Only recently have global cases dropped back to near preboycott levels
Although Nigeria has since made consider= able progress, wild poliovirus, both type | and type 3, is still circulating in the north, and vac- cine coverage there remains low In 2006, between 6% and 30% of children in the north had never received a single dose of OPV
‘Those are exactly the conditions that render an area susceptible to outbreaks of vaccine- derived virus Since the 1960s, scientists have known that attenuated viruses can in rare instances mutate and regain virulence, but it was only in 2000, with an outbreak in Hispan- iola, that they realized VDPVs could spread disease from person to person
The current outbreak came to light when a technician at the CDC polio lab noticed a pre- ponderance of type 2 virus in the isolates sent in from northern Nigeria That instantly raised suspicion, Kew says, because wild type 2 poliovirus has been eradicated globally That ‘meant the only possible source was the triva- lent vaccine, which had been used in Nige preboycott campaigns Since Nigeria resumed vaccinations in 2004, says Kew, it had “quite properly” been using the more effective mono- valent vaccinesagainst wild types 1 and 3 in its campaigns Genetic analysis quickly con- firmed the source; it also suggests that several VDPVs emerged independently in 2005 and 2006, multiple times
In earlier outbreaks, circulating VDPVs have been relatively easy to stamp out, but this, ‘one has persisted despite four campaigns with trivalent OPV in the past year “We suspect itis simply because the coverage wasnot adequate; we don’t believe there is anything exceptional about this virus,” says Kew As evidence, he notes that two VDPV strains jumped from Nigeria to Niger, where routine vaccination is, almost 90% Both “barely made it 5 kilometers before they dead-ended,” he says
Trang 27
ENVIRONMENTAL POLICY
The science of forest fire:
Tougher Ozone Accord Also Addresses Global Warming
‘Come for the ozone layer, stay for the climate That come-on might have been the marketing spiel for negotiators meeting last week under the aegis of the United Nations Environment Programme to strengthen the Montreal Proto- col, the 20-year-old accord on chlorofluoro- carbons (CFCs) and other chemicals that deplete the ozone layer And it worked The delegates who returned to the city from which the 1987 treaty got its name also made signifi- cant progressin combating global warming by recognizing the fact that most chemicals affected by the treaty are also potent green- house gases and that restricting them pays double dividends
The thin shell inthe stratosphere that pro- tects Earth from the sun's rays has a variety of enemies, and the Montreal Protocol has g been tightened four times as scientists have placed restrictions on newly recognized g threats As a result, the rate of harmful emissions has slowed (see graph), and more than 90% of the production and use of ‘ozone-depleting chemicals has been phased ‘out The biggest threats may have passed, say experts, but this year's weeklong meeting set itself two main goals: to clamp down on ozone-harming refrigerants that have £ become prevalent in the developing world, 8 andto do it ina way that could provide tangi-
ble side benefits for climate
Bythe endofthe meeting, they couldclaim to have met both goals Most impressive was an agreement by delegates to push forward by a decade a legally binding schedule to phase out in developing nations a family of chemi- cals called hydrochlorofluorocarbons
2 (HCFCs) The 191 participating nations also
§ pledged to finance a transition fund, currently & funded at roughly $150 million per year, to § support the conversion to alternatives And $ with the urging of US officials, the delegates
& also pledged to make sure that the HCFC
replacements would have the lowest possible
= harmful impact on global warming
“The delegates deserve lots of credit for
8 both recognizing and seizing a historic oppor-
2 tunity to protect both the ozone layer and the climate” says Alexander von Bismarck of the
§ Environmental Investigation Agency, a
5 London-based nonprofit that has monitored wwwsciencemag.org
the treaty Activists hope the action gives ‘momentum to international meetings on cli- mate change occurring in New York and Washington, D.C ,as Science went to press
The Montreal Protocol arose out of two scientific developments In 1974, chemists, F, Sherwood Rowland and Mario Molina cal- culated that CFCs, a common ingredient in spray cans, could destroy stratospheric ozone Although that discovery led to some voluntary curbs on their use, the impetus for mandatory action came in 1985, when British scientists ‘measured an ozone “hole” over the Antarctic The new agreement is consistent with the findings of a scientific assessment in August Production A Chinese HCFC factory Ss 2 s Ỹ = § 9 1960 1970 1980 1990 2000 2010 2020 Year
Protection The 1987 ozone treaty has reduced global greenhouse gas emissions that otherwise would have risen sharply
that said an accelerated HCFC phaseout in developing countries would produce the ‘equivalent savings of 18 billion tons of carbon dioxide emissions by 2050 HCFCs were ‘meant to bea transition chemical as countries phased out CFCs, but they have been widely used as coolants in the booming economies of China and India
The agreement would freeze HCFC pro- duction by developing nations in 2013 2 years earlier than planned—followed by successive cuts until production was ended in 2030, a decade sooner than previously agreed Developed nations agreed to advance their deadline for a phaseout from 2030 to 2020, as well as promising to pro- vide “stable and sufficient” funds for replacements while “taking into account global warming potential” in deciding which chemicals to accept as substitutes
“You couldn't have imagined this 5 years ago,” says Durwood Zaelke of the nonprofit Institute for Governance and Sustainable Development (IGSD) in Washington, D.C ‘The current availability in China of products
with many of the HCFC alternatives bodes well for the new agreement, says DuPont chemist Mack McFarland An important river during talks was a statement from the G8 summit in June, pushed by the US., pledging the industrial powers to climate- friendly action on ozone “It's being held up [as an inspiration] by all the parties” during id IGSD's Scott Stone, who showed]
‘great leadership by the White House
Thereviews weren't entirely positive, Del- egates agreed to U.S demands to continue an ‘exemption for ozone-unftiendly methyl bro- mide, a firmigant used by US farmers, allow- ing annual emissions of 4600 tons David Donigerof the Washington, D.C.-based Natural Resources Defense Council, which wants a full phaseout, called that “a black mark” on an otherwise strong U.S performance White House environment aide James Connaughton says US negotiators hope to build on the suc- cess in Montreal during a 2-day meeting hosted by the Bush Administration this week attended by representatives from 15 industrial nations and majoremitters -ELIKINTISCH
Trang 28
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Trang 29BIOWEAPONS
Panel Wants U.S Program to Retain Its Russian Roots
n Obolensk, Rus- sia, wanted to ship a strain of anthrax toa lab in Fort Detrick, Maryland, under a US pro- ‘gram intended to prevent former bioweapons scientists from selling their expertise to ter- rorists or “rogue” nations, But the Russian government wouldn't give the Obolensk lab an export license
Such setbacks are one reason the Depart- ment of Defense (DOD) has decided to phase out collaborative research projects in Russia under its Biological Threat Reduction Program But a new report by the U.S National Academies’ National Research
Council (NRC) says the agency is making a Wh TCR Former Soviet Unio Biosecurity and CỔ Bia) Total Funding $430 million
Whose threat? U.S entities have received most of the money for research on reducing the threat of Russian bioweapons
mistake, It calls on DOD to increase support for the program and to give Russian admin- istrators and scientists a greater voice in determining its direction
Since 1998, the agency hasspent more than $430 million on dismantling biological ‘weapons production centers, improving secu- rity at research facilities, setting up disease sur- veillance networks, and supporting scientists throughout the region, The activities are part of the US government's biological nonprolifera~ tion efforts in the former Soviet Union DOD officials plan to continue, and even increase, support for scientists in other countries in the region, But the difficulties in gaining access to Russian labs, combined with an improved out- look for funding science that stems from the country’s robust economy, have made Russia the odd man out “We think the Russians are now perfectly capable of transitioning their for- ‘mer weapons labs to make them part of their wwwisciencemag.org Dismantling
public health system,” a senior DOD official told Science this summer
‘The academies report, requested by DOD's Defense Threat Reduction Agency (DTRA) at the urging of Congress, takes a different view “Although the economic situation in Russia is stabilizing, the future ofa large number of bio- logical institutions is in flux,” it says “And many former weapons scientists remain trapped in uncertain circumstances that could raise serious proliferation concerns.” The bottom line, according to NRC’s Glenn ‘Schweitzer, is that “Russia is too important a country to not engage in
‘The report cites the program's success in improving security at a number of Russian labs And it sugges that heeding the wishes of its Russian hosts would strengthen the program, “DOD continues to be interested only in studying pathogens it considers dan- gerous for bioterrorism, while the Russians want to tackle health problems like cholera and tuberculosis, cexphins Sonia Ben Ouagsham- Gormley of the Monterey Institute of International Studies in Washington, D.C The fact that most of the money has gone to U.S contractors and visiting scientists has also soured Russians on the program, the report notes
‘The panel's recommendations are right on the mark, says Carleton Phillips II, a biol- i Tech University in Lubbock and the principal investigator on a DOD- funded project in Kyrgyzstan aimed at map- ping the distribution of mammals that are reservoirs of infectious diseases He says the best way to reduce biological threats in the former Soviet Union is to “engage local sci- entists in true collaborations.”
Now that the experts have spoken, will DOD listen? A DTRA official says the report “will definitely have an impact on the future of the program,” adding that the agency plans to respond before the end of the year A staffer on the Senate Foreign Relations Committee also likes the report's recommendations “There is, basic support on the Hill fordoing more collab- orative research in Russia,” he says =YUDHIIIT BHATTACHARJEE facilities $15 M JENCE Dam Californians
California Governor Arnold Schwarzenegger has fired the latest shot in the state's peren- nial battle over water, He's proposed a $9 bil- lion bond measure to increase the state's water supplies by, among other steps, bi ing two new dams in the north of the state ‘and channeling water through or around the Sacramento-San Joaquin River delta The environmentally sensitive delta is beset by crashing fisheries, pollution, and invasive species (Science, 27 July, p 442)
Schwarzenegger says the new water infra structure is part of a “comprehensive fix.” But ‘opponents say water conservation isa better solution Science should help sort out the ‘options, says Peter Moyle, a fisheries biologist at the University of California, Davis: "There's a lotwe don’t understand [about] how these plans will affect fish.” ~ROBERT F SERVICE
OPE
Pounds for Paws
Britain's largest medical research charity hopes to help veterinarians keep up with the latest developments with 2 $22.5 million ini- tiative to recruit them into research In 2004, the U.K government provided $43 million to boost the number of scientists trained to tackle challenges such as foot-and-mouth disease But that program ends in 2009 Last week, the Wellcome Trust made awards to seven U.K vet- erinary schools for efforts including summer
‘courses and postdoctoral training "Th absolutely vital development,” says Christopher Stokes ofthe University of Bristol, one of the recipient universities =ELIEDOLGIN
White House: Risk-Averse
After getting slammed by the National Acade- mies’ National Research Council (NRC), the White House Office of Management and Bud get (OMB) has decided not to issue a contro- versial directive on risk assessment The draft
bulletin, released in January 2006, contained ‘uidelines and technical standards on issues such as expressing uncertainties in federal risk assessments But a subsequent NRC report requested by OMB called the approach “fun- damentally flawed,” saying, for example, that it would require uncertainty analysis "beyond the current state of the science” (Science, 19 January, p 316) In reversing the move, OMB has instructed agencies to follow “gener ally accepted principles for risk analysis” issued by the Clinton Administration That's “good news for the science community,” says Rick Melberth of the advocacy group OMB Watch in Washington, D.C ~ERIK STOKSTAD
Trang 30i NEWS OF THE WEEK
1846
NEUROSCIENCE
Uncovering the Magic in Magnetic Brain Stimulation
In recent years, neuroscientists and psychia- trists alike have touted the potential uses of noninvasive brain stimulation technique called transcranial magnetic stimulation (TMS) The ‘method has been used to disrupt neural activity experimentally in studies of human cognition, and it has shown promise in clinical trials for treating psychiatric disorders such as depression (Science, 18 May 2001, p 1284) Although widely considered safe—thousands of people have received TMS—relatively little is known about how it actually works Now, a detailed look at its effects shows that TMS can boost or dampen the firing of neurons depend- ing on ongoing brain activity
Neuroscientists at the University of Cali- fornia, Berkeley, applied TMS to the cerebral cortex of cats while monitoring neural activ ity and metabolism Their findings, reported on page 1918—and future investigations of this type—will have important implications for how TMS is used in people, other researchers say
One interesting possibility, according to Mark George, a psychiatrist at the Medical University of South Carolina in Charleston, is, that it may matter what subjects think about while they're being stimulated, a factor that hasn't received much consideration to date George, who pioneered TMS therapy for depression, says a better understanding of how TMS works will enable researchers and clini- cians to apply it more effectively: “This is pre- cisely where the field needs to go.”
Ina typical TMS procedure, technicians place a ring-shaped paddle near the scalp ENGINEERING
Electric currents swirling inside the paddle produce a magnetic field that in turn gener- ates currents in the underlying brain tissue These currents alter the electrical activity of neurons, but exactly how they alter it is poorly understood
Stimulating results New research hints at the mechanisms of magnetic brain stimulation,
Led by Ralph Freeman and graduate stu- dents Elena Allen and Brian Pasley, the Berke- ley scientists applied TMS to the visual cortex of anesthetized cats and tracked the aftermath using probes developed in Freeman's lab that can simultaneously record the electrical activ= ity of neurons and measure fluctuations in oxy-
Pollution Slows China's Canal Project
The first phase of a massive project to replumb some of China’s mightiest water- ‘ways has fallen far behind schedule because local authorities don’t want to pay forthe priv- ilege of drinking pottuted water
‘The South-to-North Water Diversion Project is a three-stage effort to alleviate chronic water shortages in the country’s more populous but parched northern plains (Science, 25 August 2006, p 1034) The eastern route makes use of an existing net- work of canals, rivers, and lakes to pump and move water from the lower Yangtze River to Jiangsu and Shandong provinces But this month, the official Xinhua news agency announced that the first phase of the route,
28 SEPTEMBER 2007 VOL317 SCIENCE
scheduled to begin operating this year, has been delayed at least 3 years
Nearly half of the $4 billion cost of the first phase is earmarked for improving the quality of the water However, the central government is footing only about 10% of the bill, with the rest expected to come from localities that will benefit from the project But because nobody wants to clean up some- body else's dirty water, few treatment facil ties have been built along theroute, and water quality continues to deteriorate So far this year, according to Xinhua, the water is drink- able at only one of the 21 monitored cross sections in Shandong
‘Some engineering experts say the entire
‘gen concentration, an indicator of energy con- sumption Using optical imaging methods, the researchers also tracked hemoglobin levels, another metabolic marker A train of TMS pulses lasting a few seconds caused an imme- diate increase in neural firing that lasted for abouta minute, followed by a decrease in firing for several minutes Oxygen and hemoglobin mirrored this pattem, indicating that neurons” firing and energy demands go hand in hand
TMS had a dramatically different effect, however, on neural activity evoked by black and white bars flashed on a computer screen (Such responses persist even in anes- thetized animals.) In this case, neural firing dipped sharply after TMS and remained suppressed for several minutes
The findings have implications for design- ing TMS therapies, says George For depres- sion therapy, for example, “we may need peo- ple to become sad in the chair while stimulat- ing [them],” George says “Alternatively, we ‘might have them engage in formal cognitive therapy, thinking positive thoughts.” Such con- siderations are important, he adds, as the Food and Drug Administration is considering approval fordaily TMS of the prefrontal cortex to treat depression
The new findings also suggest why the effects of TMS often vary, says Alvaro Pascual- Leone, a neurologist at Harvard Medical School in Boston, Pascual-Leone suggests that TMS results could be made more consistent by monitoring the physiological state of the brain using eleetroencephalography orfunctional ‘magnetic resonance imaging, ~GREG MILLER
project itself needs to be rethought, with a greater emphasis placed on improving the ecology of the Yellow and Huai river basins Dredging the Grand Canal north of the Yellow Rivertomake the ancient waterway navigable, they say, would provide a greater benefitto the region and, thus, attract more investment,
Qian Ye, a climate researcher at the U.S National Center for Atmospheric Research in Boulder, Colorado, thinks the Chinese government should do a more com- prehensive feasibility study of the project that considers the impact of climate chan; Global warming, he says, could make China's north wetter and allow authorities to scale back the controversial project -HAOXIN
Trang 31
CLIMATE CHANGE
Long story A lengthy sediment core tells of an earh than,
' a
=
A Far-South Start for Ice Age's End
Where was the thermostat switch that, once thrown, began to thaw the world out of the last ice age? Paleoceanographers long assumed that it lay in the North Atlantic Ocean some- where; then the tropical ocean gained popu- larity in some quarters But now, strong new evidence fiom the tropics places the start yet farther south, in the waters around Antarctica The result “is all very solid, very hard to ques- tion,” says paleoceanographer William Ruddiman, professor emeritus at the Univer~ sity of Virginia, Charlottesville, “But it also tells us things are complicated There are just layers of complexity to this’
Finding where it all started “comes down to timing,” says paleoceanographer Lowell Stott of the University of Southern California in Los Angeles But determining the timing of climate events can be tough when, say, warm- ing in the tropies is recorded in marine sedi- ment, whereas warming in Antarctica is recorded in glacial ice Those are dated by entirely different methods, which injects an uncomfortable amount of uncertainty
Stott and colleagues Axel Timmermann, a modeler at the University of Hawaii, Manoa, and paleoceanographer Robert Thunell of the University of South Carolina, Columbia, elim- inated that uncertainty, at least, by gauging changing temperature in western Pacific ‘Tropical Pacific Sea Surface Temperature lh beep Pci in, Water Temperature a “fe ae
A southerly start Water from near Antarctica (bottom) watmed before the tropics (top) hear: pHOTO}L 9 STOTT/NINERSITVOF SOUTHER CAUFORNK, GRAPHIC) ADAPTED FROM LD STOTT ETAL SCIENCE wwwisciencemag.org
surface waters and in Antaretic waters ina sine gle sediment core recovered just west of the Philippine island of Mindanao At any point in the core, microfossils that had fallen from western Pacific surface waters recorded tem- perature there in their oxygen isotopic compo- sition, whereas microfossils that always lived on the sea floor recorded the temperature of bottom water that had sunk from the surface of the Southem Ocean near Antarctica Then the ‘gt0up radiocarbon-dated the sediment
The results, reported online at www sciencemag.org/cgi/content/abstract/1 143791, ‘were startling In an earlier Science paper, ‘Thunell and Stott had concluded thatthe tropi- cal Pacific had warmed first, presumably causing glacial ice to begin melting But their new analysis shows that more than 18,000 years ago, Antarctic waters warmed 1000 to
1300 years before tropical waters,
Starting from that timing and drawing on other dated records, Stott and colleagues spin a tale of how the ice started melting First, predictable variations in Earth's orbit and tilt increased the amount of sunlight hit- ting high southern latitudes during austral spring That warmed things up locally and shrank the sea ice back toward Antarctica, uncapping the Southern Ocean and freeing ‘much ofits carbon dioxide to begin warmin the whole world
Nice story, other researchers say, and the starting point at least seems fairly solid “I think they make a convincing case that something is happening at high southern la itudes before tropical temperatures change, says paleoceanographer Jean Lynch- Stieglitz of Georgia Institute of Technology in Atlanta, But, as she and Ruddiman both note, putting together the deglaciation story is “a tricky business.” And there are dissent- ing voices Paleoceanographer David Lea of the University of California, Santa Barbara, says it isn’t so clear polar warming preceded tropical warming, given the difficulty of picking out exactly when the tropical warm- ing began All agree that finishing up the story in the Northern Hemisphere—where most ice melting eventually occurred—will takemuch more work -RICHARDA KERR JENCE Bank Withdrawal
Both U.S senators from New York—Hillary Clinton (0) and Charles Schumer (O}—are demanding that the U.S Department of Vet- erans Affairs (VA) create a gene bank at the
University at Albany in New York state The pair argues that the project was approved but that the VA never followed through The idea
has enormous potential: More than 7 million veterans could donate DNA But for now itis tangled in controversy After inking an agree- ment with the university nearly 4 years ago, the VA began to pursue a gene bank project ‘on its own, upsetting the Albany group, which is led by cancer biologist Paulette McCormick (Science, 29 July 2005, p 684) Last week Clinton and Schumer took up the case, sug- gesting in a letter to VA Secretary R James Nicholson that “the Department may be using the concepts developed by Dr McCormick to establish a gene bank in another location.” ‘They urged the VA to set up a gene bank at
SUNY-Albany
Joel Kupersmith, the VA's chief research and development officer, declined to comment ‘on the dispute But he says that although VA researchers are only collecting specimens for individual projects now, “our plan in the long tunis to assemble a vast store that could be used by outside investigators
JENNIFER COUZIN
NuSTAR Is Reborn
NASA resurrected a mission to study black holes, last week and now plans to orbit the spacecraft by 2011 The Nuclear Spectroscopic Telescope
‘Array (NUSTAR) will use high-energy xrays to image the areas around black holes that con- ‘gregate at the center of galaxies Thespace agency killed the idea in 2006 because of fund- ‘ng constraints But NASA science chief S Alan Stern said in a statement that he reversed that decision because “we're getting more and more from the science budget we have, and the restart of the highly valued NUSTAR mission is ‘an example of that.” That's music to the ears of the researchers who thought all was lost fr a imission originally stated for launch this year “I'm personally incredibly excited,” says Caltech physicist Fiona Harrison, the principal investiga- tor on the project
Not every project got good news last week Stern also approved a plan to reduce the num- ber and complexity of instruments on the Mars Science Laboratory because of cost overruns Thats raising howls from Mars exploration advocates The Pasadena, California-based Planetary Society called the move “penny-
‘and pound foolish.” =ANDREWLAWLER
OPE
Trang 32
THE UNIVERSE: THERE’S NOTHING ELSE like it So if the cosmos is strange in some wa how would you tell? That may sound
beginning of an annoying argument among philosophy majors But cosmok
been debating just this point as the; ure out whether—just maybe
even weirder than they thought
The controversy has been simmering for some time, In 2003, NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) satel- lite measured the light lingering from the big bang (Science, 14 February 2003, p 991)
Researchers charted the slight variations in the temperature of the radiation, known as the cosmic microwave background (CMB), to produce a sky map resembling a dimply lime
d statistically, that iconic map bol- stered a bizarre scenario called inflation, in which in a billionth of a trillionth of a tril- lionth ofa second, the newborn universe dou- bled and redoubled in size 100 times over, stretching each atom-sized volume to the size ofa galaxy
But the map led to some mysteries, too Within 6 months, one team had found a curi- ous alignment of certain undulations in the CMB Others soon found more correlations that suggested that the cosmosmight be skew~ ered like a meatball on a toothpick by an “axis,
‘our universe is,
28 SEPTEMBER 2007
ofevil:” That axis might show that the universe has astrange shape or is rotating Itcould trash cosmologists’ cherished assumption that the universe has no center and no special direc~ tions, the so-called cosmological principle that traces its origins to Copernicus Or it Everyone grees it’s there,” says Kate Land, a cosmolo- st at the University of Oxford in the U.K ‘But isit significant?”
There’ the rub: With only one universe to measure, it may be impossible to tell Modern cosmol
cal theory mixes the elegant predictabil- ity of Einstein's the- ory of gravity with the inherent ran-
domness of quantum mechanics, which held sway when the universe was just an infinitesimal spe
the statistical or average properties of the rse, bụt not the individual quirks and coincidences caused by random quantum fluctuations all those billions of years ago,
Moreover, although the universe in toto may be infinite, we see only a finite part of it Because the univ
the speed of
So theorists can predict
VOL 317 SCIENCE
fast we'll never glimpse it So the axis could hintat some fundamental feature of the entire universe Or it could be a meaningless pecu- liarity of the bit we can see, our so-called Hubble volume or observable universe Deciding will be difficult, as it's impossible to peer into neighboring Hubble volumes or to repeat the “experiment” that produced our
homey patch of the infinite
The main problem with cosmology is our sample size—that of just one universe,” Land says “If our universe is unusual, what does it mean?” The
question underscores just how much cos- * observa ved
“In the past, our frontier has always been set by technology; you could always build a big~ ger telescope and look deeper,” says Max
Tegmark of the Mass
(MIT) “For the first time, we've hit the final frontier:
So far, only measurements of the CMB have run up against that barrier But as cos- mologists launch studies that take all they can see as one measurement, other efforts could hit it, oo A few researchers think that the matter undermines cosmology’s status as a
Technolo
www sciencemag.org
Trang 33Weirdness ahead? Future maps ofall the galaxies willbe scrutinized for unexplained patterns science All agree that having only one obsery- able universe means that some of its quirks ‘may remain forever mysterious
Fanfare for the common universe
Like a Jimi Hendrix power chord, the CMB reverberates through time The harmonies in the electromag-
netic echo reveal the state of the universe when the chord was stantly after the big bang
According to cur- rent theory, the uni- verse popped into existence infinitely dense and hot and crammed with light
and subatomic particles Within 10 seconds, inflation stretched it immensely, before its expansion slowed to a more leisurely pace Inflation evened out the temperature of the uni- verse, stretched space as flat asa taut bed sheet, and diluted to nothing the numbers of certain pesky particles that theorists say should exist bbut that have never been seen
The big blowup also sowed the seeds for the ripples in the CMB The stretching magni fied tiny quantum fluctuations in the soup of fundamental particles, creating slight varia-
ns in its density Matter began to coalesce into the denser spots, setting off a sloshing of light and matter and leading to tiny tempera- ture variations These are the same variations conveyed by the CMB, which began shining through the cooling universe 400,000 years afier the big bang, when light-trapping pro- tonsand electrons combined to form transpar- ent hydrogen atoms
To decipher the mottled CMB map, WMAP researchers broke it down much as a ‘musical chord can be broken into individual pitches Any spherical map can be viewed as thesum of coarser and finer undulations called harmonics or multipoles For the CMB, the coarsest, the dipole, simply divides the sky into hotter and colder halves The next, the qưadri- pole, divides the sky roughly in four, into the tWo hottest and two coldest regions, and so on, Researchers measured the strengths of hun- dreds of harmonics and plotted them called power spectrum, the cosmological equivalent of musical notation specifying which notes to play louder or softer
‘The WMAP team then tried to match this spectrum to the predictions of cosmological theory They found they could do just that if experiments wewwsciencemag.org
“Cosmology may look like a science, but it isn’t a
science” because it's
impossible to do repeatable
Princeton University
the universe is precisely 13.7 billion years old and flatter than an Illinois cornfield It also hhas to contain 4% ordinary matter; 23% dark matter, which has revealed itself only through its gravity: and 73% space-stretching dark energy, which is currently accelerat- ing the expansion of the universe (Science,
19 December 2003, p 2038)
The power spectrum also rises and dips in several places, revealing how sound waves rip- pled through the tod- dler universe Infla- tionary theory pre- dicted the nature of the bumps and wig- gles, and the WMAP data fit the predictions precisely says Charl Bennett, a cosmolo- sist at Johns Hopkins University in Balti- ‘more, Maryland, and leader of the WMAP team: “It certainly was a major victory for inflationary cosmology:
—James Gunn,
The axis emerges
Amid the cacophony, however, scientists detected some distinctive harmonies In 2004, MIT's Tegmark and Angélica de Oliveira- Costa, both then at the University of Pennsyl- ‘ania, reported in Physical Review D that the hot and cold spots of the octopole pattern are arrayed around a single axis abit like the pan- cls on a basketball Moreover, thisaxis appears to line up with a similar axis for the quadru- pole They estimated the chances that the alignment is a fluke at | in 66
‘A few months later, another team found ‘more curious alignments The axis defined by the quadrupole and the octopole lies in the plane of the solar system, known as the eclip- tic, and points toward the equinoxes, the two points on Earth’ orbit at which night and day are equal length all over the planet, reported Glenn Starkman of Case Western Reserve University in Cleveland, Ohio, Dominik Schwarz of the Uni- venity of Bielefeld in Germany, and col- leagues in Physical Review Letters Then, in 2005, Oxford's Land and João Magueijo of Imperial College London reported that the next two har- monies also appear to be aligned with the ‘quadrupole and octo- pole They interpreted SCIENCE NEWSFOCI
thatas possible evidence that the universe isin fact arrayed around a special axis If that were true, the cosmological principle would go out the window The alignments are all the more suggestive because they involve the broadest undulations on the microwave sky, Land says: “If there were something odd cosmologically, this is where you'd expectit to kick in.”
Many are skeptical “If you look at a data set in 1000 different ways, you expect to find something that’s unusual at the 1-in-1000 level,” WMAP leader Bennett says Some sus- pect that the axis may be an illusion produced by an unaccounted bias in how the satellite works And even those who have studied the alignments note that exactly how unlikely they appear depends on which mathematical tools researchers use to analyze them Still, many are taking it seriously “I would say that with a bit more than 99% confidence you can say there's something strange,” Schwarz says
Axis-stential musings
Assuming theaxisis more than ameasurement error, whatt new physics might it point to? The ‘most conservative explanation is that the align- ‘ments reflect contamination from some nearby stuff that either emits or absorbs microwaves, Researchers already have to filter out the reground” microwave glare from the disk of the galaxy A signal originating within the solar system might explain the connection to the ecliptic—although that would be far more likely if the axis ran parallel to the axis of the solar system, not perpendicular to it
Such a foreground would be sexier than it sounds at first, Starkman says At the least, it ‘would reveal new astrophysics, perhaps some really bizarre form of dust Moreover, the pres- ence of a foreground from the solar system ‘would most likely only bolster the case for the cosmic axis, he says Strange though it may sound, compensating for such a foreground ‘would probably accentuate the oddities “The chances are that when you subiract it, the data will agree even less well with the theory than
Poles apart The axis of evil (poles marked red) lies almost perpendicular to the
solar system's axis (poles marked blue) and far from the galactic axis
VOL 317 28SEPTEMBER 2007
0:
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1850
they do now.” Starkman says
By far the most exciting possibility is that the axis indicates that the universe is stranger than cosmologists have assumed For exam- ple, the universe could whip up such an axis if space had an odd shape, such asa torus that wraps around and reconnects to itself “If ‘you want to explain the axis of evil, the eas: est way would be to say that our universe isa
lot like [the video game] Asteroids, where if ‘you go off the screen on one side, you come back on the other,” Tegmark says Others have proposed weirder shapes or suggested that the whole universe could be spinning around the axis
None of these tantalizing ideas has bowled researchers over, however Tegmark and de Oliveira-Costa’s doughnut universe clashes with other observational constraints Ifthe uni- verse wraps around in such a way, then researchers should see faint matching circles in the CMB onopposite sides ofthe sky (Science, 2 June 2001, p, 2237) But none have been found Other models suffer similar problems “It Stough because on one hand, I’m onthe side of saying that this may be telling us something.” ‘Starkman says “On the other hand, so far I'm unconvinced by the ideas that have been put forward for what this might be telling us.”
Of course, the axis could just bea fluke, a coincidence produced by primordial quan- ‘tum fluctuations in our particular Hubble vol- ume Although Albert Einstein insisted that “God does not play dice”—so often that oth- crs tired of hearing it—theorists now think that in making the cosmos, the metaphorical creator rolled the bones once and walked away Perhaps, like troubled gamblers, some cosmologists read too much into the fact that he tossed 2 and a3
One thing is certain: Cosmologists will never figure out what the axis of evil is by
remeasuring the CMB Researchers have measured the temperature variations in the CMB so precisely that the biggest uncertainty now stems from the fact that we see the microwave sky for only one Hubble volume, an uncertainty called cosmic variance “We've done the measurement,” Bennett says “Its not
‘going to get any better” The geology of the cosmos
Tobe sure, many things remain to be measured But cosmic variance could ultimately pinch other sorts of studies, such as galaxy surveys Researchers with the
Sloan Digital Sky Survey are using a 2.S-meter telescope at Apache Pointe, New Mexico, to map everything they can see in a quarter of the sky and have spotted 80 million galaxies so far The proposed 8.4-meter Large
Synoptic Survey Telescope (LSST) aims to tally 3 billion, By the middle of the century, researchers likely will have surveyedall 100 il- lion bright galaxies in our Hubble volume, says Michael Tumer, a cosmologist at the University of Chicago in Iltinois,
‘Such surveys aimto study the distribution of the galaxies en masse, or how the galaxies’ images are distorted by huge threads of dark matter spanning the universe In doing so, they trace the evolution of the density fluctuations thatrippled the CMB That'sbecause those fluc- ‘tuations also spawned the dark matter filaments, which in turn seeded the galaxies Even with LSST, some of those studies will buttagainstthe limits of cosmic variance, says Lloyd Knox of the University of California, Davis Going my way? The CMB quadrupole (top lef), octopote (top right), and the next two multipoles The ed dots
‘mark their symmetry axes, which appear to line up
“The fact that we can only see one Hubble volume has
not been an impediment to understanding the origin
and evolution of the universe.”
University of Chicago
‘That barrier to knowledge, some argue, is cosmology’s Achilles’ heel Cosmology may look like a science, but it isn’t a science.” says James Gunn of Princeton University, co-founder of the Sloan survey “A basic tenet of science is that you can do repeatable experi- ‘ments, and you can’t do that in cosmology’ Others don't see the problem “So far, the fact that we can only see one Hubble volume has not been an impediment to understanding the ori- gin and evolution of the universe,” Tuer says Some note that cosmic variance will limit ‘measurement of only the very largest features of the universe and that studying the myr- iad smaller bumpsand wiggles may be more revealing anyway
all agree that cosmic variance highlights a definite limit to what cosmol- ogy can tell us “The goal of physics is to understand the basic dynamics of the universe.” Tumer says "Cos- mology isa little different The goalistorecon- struct the history of the universe.” Cosmology is more akin to evolutionary biology or geol- ogy, he says, in which researchers must simply accept some facts as given For example, the theory of plate tectonies does not explain why Earth has precisely seven continents
‘That distinction may disappoint the many researchers who have come to cosmology by ‘way of physics, afield that prides itself on its rigor and unparalleled testability Many hope to connect particle physics directly tothe birth and evolution of the universe to arrive at an all-encompassing theory that, at least statisti- cally, would allow them to mathematically derive the universe “I don’t like unexplained coincidences,” Tegmark says “Generally, 1 ‘wantan explanation’
To get one for the axis, many say, researchers must press on concocting new models Others suggest looking for evidence in galaxy surveys and other typesof
that the most promising route may be to develop theories that extend to the “multiverse” of Hubble volumes beyond our own (Science, 23 July 2004, p 464) and ask why the axis might help make our exis- tence in this one more likely
Trang 35EDUCATION RESEARCH
U.S Says No to Next Global Test of
Advanced Math, Science Students After U.S high school students did poorly on TIMSS in 1995, the government has decided not to participate in another version to be given next year
In 1995, the United States lagged behind most of the world ona test of advanced math- ematics and physics taken by graduating high school students from 16 countries That ‘won't happen again, if the Bush Administra tion has its way: Ithas decided not to partici- pate in the next version of the test
ional Center for Education Statis ), part of the U.S Department of
titute of Education Sciences s bowing out of 2008 TIMSS- ‘A, an advanced version of the Trends in International Mathematics and Sci- ence Study given quadrennially to younger students, because it can’t Fit the $5 million to $10 million price tag into its flat budget Offi cials also question whether the tar- get cohort —students finishing sec- ondary school who have taken advanced mathematics and physics courses—is comparable around the world
But many leaders in the mathe- matics community believe that the Administration opted out because it feared another poor U.S performance would reflect badly on its signature education program, the 2002 No Child Left Behind Act While advocates of the test look for other sources of funding, Science has learned that the National Board for Education Sciences, which advises IES, will ask for a review of the decision next month
International tests have proliferated in recent years as countries seek ways to m ure how well they are preparing students for jobs in a global economy And although fourth- and eighth-grade U.S students have performed adequately on the TIMMS tests, high school seniors have not In 1995, the last
that cohort was measured, U.S students topped only Austria in advanced math and ranked dead last in physics
Planning for 2008 TIMSS-A began in 2006 at the urging of Norway and Sweden Although 16 countries participated in the first test, only nine—the two proponents plus Russia, Italy, the Netherlands, Slovenia, Iran, Lebanon, and Armenia—have ponied up for wewwsciencemag.org
thenew test, which covers geometry, algebra, and calculus as well as mechanics, electricity and magnetism, heat and temperature, and atomic and nuclear physics Sometime last year, NCES quietly decided not to get involved, and since then Australia, Germany, and Finland have also dropped out
Leaders from the U.S mathematical co munity, including the National Council of
Teachers of Mathematics and the American Mathematical Society, are up in arms at the department's decision, first reported last month by the newspaper Education Week They argue that this elite group of students needs to be monitored because they are most likely to major in STEM (science, technol- ogy, engineering, and mathematics) fields in college and become the next generation of scientists and engineers, “It's inconceivable tome that the government wouldn't fund our participation.” says Stanford mathematician R James Milgram, a member of the IES advisory board that expects to take up the issue at its 30 to 31 October meeting “The 1995 test was extremely important in show- ing thata problem exists,” he notes “And the only way to know if we're beginning to turn things around is by looking at new data to see if we've made any progress.”
In defending their decision, NCES offi- cials note that they are already supporting
(0⁄33)5637L7E)x345(x)+1549.3523(x23)(47
NEWSFOCUS L
lar 2007 TIMSS for fourth and eighth graders, a fourth-grade reading exam, a math and science assessment of 15-year- olds, and a planned survey of adult literacy They say that USS, students may be at a dis- advantage because some TIMSS-A test takers from other countries are older and may have specialized in math and science during the latter part of their secondary school years In addition, says NCES associ- ate commissioner Valerie Plisko, whose office manages the various international assessments, “we typically do not bench- ‘mark against these countries.”
But those explanations don’t pass muster with critics TIMSS-A “is not just a horse race,” responds Patsy Wang-lverson, coordi- nator of the group advocating US partieipa- tion and also vice president of the Gabriella and Paul Rosenbaum Foundation in Bryn Mawr, Pennsylvania, which supports mathe- matics education She says there is much that U.S educators can learn from look- ing more closely at this population “A lot has changed since 1995,” she “Students are taking more math and science and more AP [advanced placement] courses, and TIMSS-A provides us with a wonderful opportunity to evaluate their performance If we don't do itnow, we'll lose track of an entire generation of reform efforts.”
After NCES bowed out, offi- cials at the National Science Foun- dation (NSF) asked the
tional Testing Service
Princeton, New Jersey, to propose how it would administer TIMSS-A ETS's approach also would have laid the foundation for a longitudinal study of these advanced ‘math and science students But this summer, NSF officials declined to fund the proposal after reviewers raised questions about the tar- get population and ETS's ability to improve onthe disappointingly low levels of U.S par ticipation in the 1995 test “Weld have to do more work to resolve those issues.” admits ETS’ Michael Nettles,
Trang 361852
BIOSAFETY BREACHES
Accidents Spur a Closer Look at
Risks at Biodefense Labs
Failure to report a Brucella infection and other problems at a Texas university have microbiologists searching for ways to ensure safety and public trust
An unreported infection with a dangerous pathogen and other biosafety breaches at a ‘Texas university are fueling an already heated debate about safety at U.S biodefense labs The problems at Texas A&M University in College Station, which led federal officials to shut down the university's biodefense research this summer, follow a spate of accidents at other U.S, labs in the past few years They also coincide with the accidental rel f and-mouth virus from a research facility in the United Kingdom that has shown the potential economic devastation that can result if a pathogen escapes These events are bringing new urgency to a question raised
soon after the United States began pouring money into biodefense research after the 2001 anthrax attacks: Are the nation’s biodefense labs safe enough?
“Proponents insist there is a clean safety record Thatis simply wrong Withsomeagents, it could have catastrophic consequences,” says microbiologist Richard Ebright of Rutgers University in Piscataway, New Jersey, a critic of the biodefense expansion
Although other scientists and biosafety experts say the exten- sive breakdown in procedures at Texas A&M is probably excep- tional, they too worry that many incidents are going unreported Next week, a congressional com- 2006: Brucellosis infect
mittee will examine the recent accidents and the biodefense buildup
The scrutiny is sending tremors through
university administrators and the microbiol- ogy community, which is struggling with how to both ensure safety and gain the public’s trust One idea under discussion is an anony-
mous national accident reporting system that
would enable institutions to learn from one another's mistakes
Winning public confidence could de mine whether several proposed labs, such as one being built in Boston, will be allowed to operate at biosecurity level 4 (BSL-4), the
2002, 2003: £ coli 0157:H7 infections in two USDA labs 2004: Three workers infected with tularemia, Boston University 2004: Ebola needle stick (no infection), USAMRIID
2004: Anthrax exposure (no infec
2004: Valley fever (C immitis) infection, Medical College of Ohio ), Children’s Hospital, 2005: Potential Q fever exposure, Rocky Mountain Labs, Har \n, Texas ARM
Redundancy A postive-pressure “space suit” isone of several precautions used to protect workers from the deadliest pathogens ina biosafety level 4 lab highest level used to study the most danger- ous pathogens Community support will also likely play a role in which of five competing sites wins a planned $450 million BSL-4 national agro-biodefense lab funded by the Department of Homeland Security
Some infectious disease experts worry that public hysteria fueled by watchdog groups over even relatively minor lab inci- dents will paradoxically make it harder to establish the atmosphere of trust that is essen- tial to running a safe lab “To ring all the bells and bring out the fire trucks is counter- productive,” says virologist Clarence 1 Peters of the University of Texas Medical Branch (UTMB) in Galveston But there is room for improvement, he adds: “One of the biggest problems is transparency I think we're all going to have to get past that: Into the hot zone
Trang 37CDC About 14,000 people at 400 labs now have select-agent authorization
To date, the most serious biosafety breaches have occurred outside the United States, such as several SARS infections in Asia in 2003 and 2004 that killed one researcher and infected several people outside the laband the death of'a Russian lab worker from Ebola in 2004 And some potential exposures—such as animal bites, needle sticks, and glove tears—are inevitable, U.S, biosafety experts say One of the worst recent accidents occurred at the US ‘Army Medical Research Institute of Infectious Diseases in Fort Detrick, Maryland, where a worker was exposed to the Ebola virus but didn’t become infected Others (sce table, p 1852) involved shipments of
pathogens labeled nonpathogenic that turned out to be virulent That happened with tularemia in Boston University in 2004, where three ‘workers were infected The incident ‘was reported to local authorities and made public only after delays, adding to criticism of the proposed Boston BSL lab (Science, 28 Jan- uuary 2005, p 501)
The problems at Texas A&M, however, may be the most egre- ious to date, They first emerged in April when the school belatedly reported to CDC that in February 2006, a worker was infected with Brucella bacteria, a pathogen com- ‘mon in livestock that causes fever
and fatigue in humans but is rarely sa
fatal This incident, like many oth- Cepeatinat— ỔaeviemD ers, was brought to light through Bealeylenl4 9, Bote tet
public records requests by Edward Hammond of the Sunshine Pro- ject, a watchdog group in Austin, § Texas In June, after the Sunshine
& Projectreported that three workers
2 had tested positive for antibodies to the
Q feverpathogen, CDC shut downall of Texas A&M'sselect-agent work In an August inves- ion, CDC inspectors found a dozen seri ous violations, including unapproved exper ‘ments, lost simples, improper safety training, and lab workers without select-agent authori- zation (Science, 14 September, p 1487)
Some observers suggest the Q fever anti-
2 body tests were nota major issue; none of the
‘workers became ill, and two were apparently exposed before they joined the lab, But the Brucella case, which happened when a worker leaned into an aerosol chamber to clean it, isa clear violation of safe practices: The chamber should have been decontami- nated with gas first, says Jonathan Rich- mond, a consultant in Southport, North Car- wewwsciencemag.org
olina, who oversaw biosafety at CDC in the 1990s It as added to speculation that more incidents aren’t being reported Hammond has used open-records requests to dig up examples of exposures, equipment failures, and other near-misses at various labs that ‘weren't publicly disclosed He says they sug- ‘gest other significant mishaps are hidden
Researchers and biosecurity experts say serious infections would be difficult to hide from CDC But some agree there is probably underreporting of mild infections and potential exposures Workers who make a mistake are often embarrassed and may fear angering their supervisor, and institutions worry about the damage to their reputation, says Richmond
“It's been a problem for a long time,” he says Supporting that suspicion, CDC, which has recorded about 20 accident reports a year since 2004, has received 32 reports since April 2007, possibly because of the publicity about Texas A&M, saysa CDC spokesperson
Although the multiple protocol violations at Texas A&M may be the exception, less extensive violations are not A 2006 Depart- ment of Health and Human Services (HHS) Inspector General audit of security proce- dures found that 11 of 15 institutions had “serious weaknesses” such as unlocked doors and freezers and lax inventory records Janet Shoemaker, public affairs director for the American Society for Microbiology in Wash- ington, D.C., points out that schools have a strong incentive to adhere to the rules; since
NEWSFOCUS L
2003, the HHS Inspector General has levied fines ranging from $12,000 to $150,000 on nine research institutions and companies for breaches such as unapproved select-agent shipments Texas A&M is facing fines as high as $500,000 for each violation
No public menace
‘One point of agreement among most scientists is that however scary these incidents sound
the mention of Eboia virus conjures the 1995 movie Outbreak, for example—the risk to the Publicis very low for most pathogens, fortwo reasons First, there have been no known envi-
ronmental escapes from BSL-4 labs since the
early 1980sandonly two workersareknownto
Proliferation Critics are worried about the potential for infections and escapes at biosafety level 4 (BSL) labs (ive existing, atsixleast planned) and 84 existing and new BSL-3 biodefense labs, as compiled here by the Sunshine Project
have become infected in BSL labs, both out- side the United States Workers have many lay ers of protection, including positive-pressure ‘and realize the hazards of work- ing with pathogens studied in BSL labs, for which, by definition, there are no treatments
Second, even if an agent studied in a BSL-4 lab did escape, most, with the excep- tion of smallpox (which can only be studied at CDC), are not very transmissible Anthrax doesn’t spread person to person, for example, Ebola and other hemorrhagic fevers that have killed hundreds in Africa would likely never cause an outbreak in Western countries because hygiene and medical treatments are so much better, says Peters, (He also notes that many select agents, such as anthrax and Q fever, occur commonly in nature, so people
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i NEWSFOCUS
1854
can get infected without coming anywhere near a biodefense lab.)
Some scientists and biosafety experts are more worried about risks at BSL-3 labs because the standards at these labs are not as stringent But even most of these pathogens- with the exception of SARS, avian influenza, and 1918 flu—are not very communicable, and in any case vaccines and other treatments are available At most, says infectious disease modeler Ira Longini of the University of Washington, Seattle, “the result could be a handful of cases and maybe deaths.” Another exception is foot-and-mouth disease, which doesn’t infect humans but is extremely conta- gious among animals; the escape in the United Kingdom, which has been tied to an outdated effluent treatment system, would be unlikely to occur at more modern facilities in the United States, Richmond says
worries that the “hysteria and witch by people like Hammond of the Sunshine Project is compromising safety by making lab workers worry that reporting potential exposures will get them fired “Peo- ple can’t be terrified to report,” agrees Jean Patterson of the Southwest Foundation for Biomedical Research in San Antonio, Texas, which runs a BSL-4 lab, Safety check
So how can biosafety be improved? One pro- posal is an anonymous, mandatory reporting system for all laboratory accidents Such a system would enable labs to learn from one anothers mistakes, as do the data compiled ‘on aviation accidents by the National Trans- portation Safety Board, says Gigi Kwik Gronvall of the Center for Biosecurity of the University of Pittsburgh Medical Center in Baltimore, Maryland, who co-authored a paper describing this proposal earlier this year in Biosecurity and Bioterrorism “Other industries have gone through this,” says Gronvall The system would also capture lab exposures to pathogens not on the select- agent list, such as HIV and tuberculosis Reporting these to NIH or CDCis notmanda- tory, Rutgers's Ebright notes
But some microbiologists caution that reportable incidents should be well-defined, lest the system become glutted with minor mishaps (Peters cites UTMB'S recent deci sion to release, at a community group's
5 years.) Also important, says biosafety con- sultant W, Emmett Barkley of Bethesda, Maryland, reports should include not just bare facts but analysis, as CDC now provides for selected lab accidents in its Morbidity and Mortality Weekly Report
‘A more radical idea is to require that BSL-3 and BSL-4 labs be licensed by the federal gov- ernment This would mean that all these labs, not just those working on select agents, would be inspected and they would be required to follow the same operating procedures One supporter of this proposal, biosecurity expert Anthony Della-Porta of Geelong, Australia, says the problem now is that BMBL offers only general guidance Others, such as Barkley, say institutions need flexibility, espe- cially the many BSL-3 labs that don’t do biodefense work
ECOLOGY
There's one fact that nobody dis The risk of accidents in biosafety labs goes up with the number of workers For that reason, watchdog groups and even some
biodefense researchers lament the lack of
analysis on whether all of the six planned
BSL-4 and two dozen new BSL-3 bio-
defense labs are actually necessary to pro-
tect the nation from bioterrorism (see map) Says Gronvall: “Is there too much [bio- defense research]? Without seeing the plan
Shard to sa
~JOCELYN KAISER
Setting the Forest Alight
To validate satellite data for carbon-emissions modeling, researchers this summer torched a jack-pine forest in Canada and tried to ignite a stand of larch in Siberia
KODINSK, RUSSIA—In July, as temperatures soared during a heat wave in eastern Siberia, scores of large fires flared through the region's dense pine forests For 500 kilo- meters along the Amur River northwest of Lake Baikal, thick smoke blanketed the wildern
airborne forest fire fighting service, Aviale- sookhrana, were tracking the wildfires at an airbase here in Kodinsk, a small city on the Amur They
were tense To them it seemed bizarre that a team of inter- national scientists had received permis sion to burn a patch of nearby forest Even with every local helicopter and plane conscripted to serve their firefighting crews, millions of dollars’ worth of timber was going up in smoke in wildfires, “It's not as though we don’t have enough t ‘worry about alread
mused Oleg Mityagin, the overtaxed local Avialesookhrana boss “We're in no position to help them if they lose control.”
Sixty kilometers to the west at the experi- mental site, a group of Russian, American, and Canadian researchers hoped to set a test fire that would thoroughly burn a hectare-sized patch of larch forest, Siberia’s dominant conifer Their aim was to quantify carbon Ontario, Canada
Safe distance Douglas McRae checks out a gap in a pine forest during an experimental burn in
emissions from fires in larch forests across Siberia, now inadequately documented, according to Douglas McRae, a forest-fire researcher with the Canadian Forest Service McRae has been conducting experimental burns in Canada and Russia since 199 as part of project FIRE BEAR (Fire Effects in the Boreal Eurasia Region), a research program aimed at studying forest-fire behavior, eco- logical effects, emissions, carbon cycling, and
remote sensing, Conceived in 1997, FIRE BEAR brings researchers from the
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5
Flaming wildemess
The searing summer heat in Kodinsk pre- sented a dilemma for the scientific team “We want the larch to burn well in order to obtain good data,” McRae explained, “but we risk losing control if it burs a little too well.” In the days leading up to the experi mental burn, bulldozers hacked firebreak lanes around the test patch, and researchers wired the forest floor with probes to gauge heat release, carbon emissions, and effects on vegetation and microbes McRae had ‘good reason to be anxious In May, in simi- lar weather, he and his FIRE BEAR col- leagues conducted an experimental burn near Sault Ste, Marie, Canada, in which a hectare-sized patch of bone-dry jack-pine forest fanned out of control That experi- ‘ment was meant to show how infrared tech- nology can be used to estimate fuel con- sumption and carbon emissions during fires McRae and his colleagues hoped it ‘would help them gauge how Russian wild- fires contribute to greenhouse gas em sions (Russian security laws prevent infrared filming from the air.)
Only minutes before the scientists ignited the fire in Ontario, wind gusts unex- pectedly blew through the treetops After ignition, the entire test plot flared in an explosive burst that melted computerized ‘monitoring equipment The equipment tech- nicians got out unharmed with much of the damaged, although still-functioning, gear belonging to Martin Wooster, a geographer at King’s College London,
‘Wooster believes that the amount of car- bon emitted from wildfires every year is possibly half that released by fossil-fuel con- sumption, He has been traveling the world collecting data to confirm his theory In the Canadian test, he had an opportunity to gather data at ground level and at 300 meters above the fire in a helicopter Researchers will use the observations to test the accuracy of satellite data
While making an infrared film, Wooster watched the test fire jump across the fire- breaks around the experimental site Within a few hours, more than 1400 hectares of magnificent pine forests were ablaze Water bombers, surveillance planes, and Wooster's rented helicopter scrambled to get the situation under control Wooster came away with an impressive data haul that will help to validate the usefulness of infrared measurement, he said later But Ontario forest officials were not pleased strongly doubt they'll be quick to give per- mission for more such experimental fires future,” Wooster said wewwsciencemag.org
Foresters aren't the only ones to express doubts; Russian secu- rity officials have been wary, too Thanks to an infusion of fund- 1g from the Inter- national Science and Technology Center in Moscow, which sup- ports nonmilitary collaboration between Western scientists and those within the Russ- ian weapons com- plex, FIRE BEAR has attracted former- Soviet military experts in remote sensing Other scientists have joined including members of the Siber- ian RASS Institute of Chemical Kinetics
and Combustion in Novosibirsk, as well as US researchers funded by NASA
‘Some Russians have complained of being arrested and undergoing harrowingly long interviews, says Anatoly Sukhinin, a remote- sensing expert who joined FIRE BEAR after acareer in the Soviet military “I still spend a fair amount of my time explaining our work to the police.” complained Sukhinin, sitting in his laboratory in Krasnoyarsk, which NASA helped equip to receive and interpret Siberian fire data beamed from American and Russian satellites “It doesn’t help that we're doing these experiments in a region which was until recently secret and still remains heavily militarized.”
Despite the hassles, the partnership seems to be paying off, In recent years, says Amber Soja, a research scientist with the USS National Institute of Aerospace, cur- rently resident in the Climate Dynamics branch of NASA‘ Langley Research Center in Hampton, Virginia, FIRE BEAR papers have widened knowledge of Siberian forest fires and their global atmospheric effects In 1998, Brian Stocks of the Canadian Forest Service reported a positive correlation between climate-change impacts and a increase in the severity of Siberian fires A 2004 paper by Soja, along with McRae, Sukhinin, and Susan Conard of the USDA Forest Service, concluded that disparities in the amount of carbon stored in different for- est types and the severity of fires within them can affect total direct carbon emissions by as much as 30% This is why they need specific data on larch fires, which emit less Hot results A sudden gust of wind sent flames temporarily out of controt in a Canadian test area, but the fire produced terrific data
carbon than pine In extreme fire years, they found, total direct carbon emissions from wildfires can be 37% to 41% greater than in normal ones, because severer fires consume ‘more organic matter in the forest floor
Last year, Soja, Stocks, and Sukhinin pub- lished a review of predictions of climate- induced boreal forest change Four of seven models predict that warming in Siberia will be 40% greater than the global mean, Soja spent several weeks at the FIRE BEAR camp near Kodinsk last summer, living in a tent and subsisting largely on tinned fish and buck- wheat cereal while comparing notes with her Canadian and Russian co-investigators in the run-up the test burn The predictions she co-reviewed, she says, are already coming true in Alaska, Canada, and Russia In Siberia, 7 of the last 9 years have resulted in extreme fire seasons, she explains Speaking from the camp, she said “If you are looking for climate-change impacts on forests, this is
the place to be.”
Trang 40Part rocket Part rocket science
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