News this Week

Science  12 Mar 2004:
Vol. 303, Issue 5664, pp. 1590
  1. SPACE PHYSICS

    Will NASA Annihilate Station Antimatter Experiment?

    1. Andrew Lawler

    NASA is reconsidering its support for an innovative experiment designed to capture direct evidence of elusive antimatter. At stake is an unusual 16-nation effort, led by a Nobel Prize winner, that until recently was cited by agency managers as proof that the space station can host high-quality science.

    A full review of the project, called the Alpha Magnetic Spectrometer (AMS), could begin this summer, says Bernard Seery, a deputy chief of NASA's biological and physical sciences office. NASA's actions stem from President George W. Bush's decision in January to concentrate space station work on experiments related to human exploration (Science, 16 January, p. 293). That pushes basic research endeavors such as AMS to the periphery. “We're going through a rethinking process,” says Seery.

    AMS was conceived a decade ago by Massachusetts Institute of Technology physicist Samuel Ting, who won the Nobel Prize in 1976 for discovering a new particle. It is designed to detect primordial antimatter, which has never been found in nature although theoretically antimatter should make up half the universe. Why there is such apparent asymmetry between matter and antimatter in the universe remains a cosmological mystery.

    After high-altitude balloon experiments failed to detect any evidence of such antimatter in cosmic rays, Ting proposed putting in space a large magnet with sensitive detectors. Attached to a space station truss, AMS would monitor high-energy particles, noting their velocity and their path through the instrument. Ting hopes evidence of antimatter nuclei could be extracted from the data. The experiment also would search for exotic particles that might provide clues to the origin and nature of the dark matter that apparently makes up the bulk of the universe.

    Ting's proposal was welcomed by then—NASA Administrator Daniel Goldin, who at the time was fighting off congressional attempts to cancel the space station and was eager to attract scientific heavy hitters that could give it credibility. Goldin gave the go-ahead after a prototype flown on the shuttle in 1998 proved that the concept was feasible.

    Adrift?

    NASA may review its plans to launch Samuel Ting's antimatter detector on the shuttle and attach it to the space station.

    CREDITS: (LEFT TO RIGHT) HOMER NEAL; JOHN FRASSANITO & ASSOCIATES INC.

    Although Ting is counting on NASA to provide the container that holds AMS and transport it to the space station via the shuttle, the project is nominally managed by the Department of Energy. That unusual administrative arrangement was intended to keep AMS free of endless NASA scientific reviews and funding fights. Ting took on the job of finding collaborators to build the superconducting magnet and related hardware, which he says will cost $840 million. A diverse coalition that includes researchers at Geneva's CERN, Taiwanese engineers, Chinese scientists, and U.S. aerospace companies is busy at work on the project.

    But all that work could be undone if NASA withdraws its support. The agency has spent about $22 million on AMS and has budgeted another $10 million to $20 million to complete work on the vacuum case and associated hardware to carry Ting's magnet. The current plan is to build the case in Los Angeles, install the superconducting magnet in the United Kingdom, and add the detectors at CERN. The payload would be tested in the Netherlands, then shipped to the Kennedy Space Center in Florida to prepare for a 2007 launch.

    That arrangement would need to be dramatically altered, however, if NASA pulls its support and withdraws its offer to fly the experiment to the space station. Seery says one option would be to launch AMS on an expendable launch vehicle and fly it freely in space. “It could go that way,” he says.

    That change could make the project more expensive, however, because it would require purchase of a launcher as well as a “major redesign,” says James Bates, the mission manager of NASA's portion of the project at Johnson Space Center in Houston. The AMS hardware is now tailored for the relatively soft ride aboard a shuttle and a perch on the station that includes built-in power and control systems. A free flyer, says Bates, would need to be hardened to survive the rougher ride aboard an expendable rocket and would also need its own power and control systems.

    Ting says that no one at NASA has told him of any potential review and that “I've never thought of” a free-flying AMS. He says his relationship with the space agency is excellent and he expects NASA “to respect our international collaboration.” But he also intends to meet next month with Craig Steidle, NASA's new exploration chief, to emphasize AMS's potential benefits for astronauts headed beyond Earth orbit.

    AMS could provide crucial data on cosmic nuclei, which would be vital to planning long-term human missions, Ting says. And a lightweight magnet similar to AMS might even help a future spaceship protect its human crew from dangerous cosmic rays. “It should be easy to build a magnetic shield,” he says. Gathering data relevant to human missions is certainly a possibility, adds Seery. “A little change in voltage and a tweak” could allow the AMS to test that idea and contribute to the body of knowledge on human exploration, he says. “It wouldn't take that much retrofitting.”

    Like Ting, DOE officials said last month they were not aware of any impending review of AMS. In the meantime, Seery has ordered Bates and his Johnson Space Center colleagues to find ways to save money. Bates hopes that budget constraints don't undermine what he calls the only major scientific payload scheduled to be strapped to the space station. “This is Hubble-class science for high-energy particles, and NASA is only paying 5% of the bill,” he notes. “It seems like a darn good deal for us.”

  2. TRANSGENIC CROPS

    Britain Opts for Brave New GM World

    1. Gretchen Vogel

    After 5 years of acrimonious debate, the U.K. government on 9 March gave a qualified thumbs-up for commercial planting of the first genetically modified crop—GM maize—on British soil. Following the lifting of a European Union moratorium last year, Brussels will now consider opening the door to planting the variety across the E.U.

    The long-awaited approval is a mixed verdict. Hewing to advice from the British Advisory Committee on Releases to the Environment (ACRE) (Science, 23 January, p. 448), the U.K. government also said it opposes commercial planting of two other GM crops: sugar beets and oilseed rape. Farm-scale trials showed that growing those crops resulted in fewer weeds and insect species in the fields, possibly undermining biodiversity (Science, 24 October 2003, p. 542).

    Corn was a different story. In the farm-scale trials, herbicide-tolerant maize fields had more weeds and a wider range of insects than those sown with conventional varieties. For that reason, U.K. Environment Minister Margaret Beckett told the House of Commons, GM maize did not pose added risk. But she attached several conditions to approval of commercial planting, stipulating for instance that the crop must be grown only in the manner tested in the trials.

    The decision shows that the GM regulatory process in Britain is working, says ACRE chair Christopher Pollock. “When the scientific evaluation [of GM varieties] is done, the government will make a decision and things will move forward,” he says. Indeed, Beckett told Parliament, the government will consider each variety case by case.

    Although essential, Beckett's endorsement is not the final word. The Pesticides Safety Directorate still must approve the herbicide used with GM maize, and the decision must be sanctioned by authorities in Scotland and Wales, where it could meet stiff resistance. The earliest the crops could be planted in the U.K., Beckett said, is in spring 2005.

  3. POLAR RESEARCH

    Plucky Scientists Plucked From Jaws of Death

    1. Theres Redeby*
    1. Theres Redeby was an intern in the Cambridge, U.K., office of Science.

    CAMBRIDGE, U.K.—A dozen Arctic researchers are home safe after a bizarre incident transformed a remarkable scientific adventure into a survival test. Three days after a sudden uplift of ice demolished most of their research station, North Pole 32, all the crew members were rescued on 6 March.

    North Pole 32 was the first new Russian polar station in 12 years. The researchers were dropped off last April for a yearlong stint to study global warming, weather patterns, and interactions between the ocean and atmosphere. But when they were wrapping up their fieldwork and preparing to take down the camp, their world began to fall apart around them. “The moving ice put pressure on the station from three sides simultaneously, causing deep cracks to develop,” says station chief Vladimir Sokolov of the Arctic and Antarctic Research Institute (AARI) in St. Petersburg, Russia.

    Kept their cool.

    Some of the polar researchers the day after a helicopter whisked them to safety.

    CREDIT: VLADIMIR STRUGATSKY/EPA/AP

    As the cracks spread over the next couple of hours, the researchers calmly moved equipment, food, fuel, and most of their data to more stable ice. Their retreat was not a moment too soon: The shifting ice thrust a huge slab 10 meters into the air; it came crashing down on the abandoned camp, destroying 13 of the 16 buildings.

    Although they escaped harm, the researchers could salvage only a few days' worth of food and fuel—and, crucially, their GPS transponders. The station, about 650 km from the North Pole, between Greenland and the Norwegian island of Spitsbergen, was barely within helicopter range. After weather conditions improved enough for the 6-hour flight, the team was located quickly and whisked back to a temporary rescue base on Spitsbergen, then on to St. Petersburg. The stoic researchers insist that their lives were never in danger.

    AARI too is putting on a brave face: It's building a new research station for a fresh team in September.

  4. REPRODUCTIVE BIOLOGY

    Textbook Rewrite? Adult Mammals May Produce Eggs After All

    1. Jennifer Couzin

    A baffling inconsistency in a Boston lab is threatening to overturn a dogma of reproductive biology: that female mammals produce no new eggs after birth. A series of studies on mice has prompted a flabbergasted team of biologists to conclude that mouse ovaries harbor a previously undiscovered type of stem cell that can form new eggs through adulthood. The finding has far-flung implications, touching on everything from fertility and aging to the childbearing capacities of young cancer patients.

    Everyone assumed “that because there was a decreasing number [of eggs] from the embryonic state to the menopausal state, that you didn't make new ones,” says Ted Trimble, a gynecologic oncologist at the National Cancer Institute in Bethesda, Maryland. That now looks like “an incorrect assumption.”

    The discovery, chronicled in a paper in this week's issue of Nature, came about by chance. Jonathan Tilly, director of the Vincent Center for Reproductive Biology at Massachusetts General Hospital in Boston, and his colleagues were studying ovarian failure in cancer patients. Chemotherapy and radiation treatments frequently destroy ovarian function, and Tilly's group sought to compare that failure with normal ovarian aging. To establish a benchmark, they harvested ovaries from mice at different stages of life and counted the healthy follicles, each of which holds a single oocyte, or egg cell. Then they counted the number of dying egg cells in the same animals; these cells remain visible for several hours before they're cleared from the body.

    The scientists were taken aback to find that up to 1200 oocytes were dying at any given time by the time the animals approached adulthood. (Mice are born with roughly 5000 oocytes.) Given this, “it would be impossible for ovaries to last longer than 2 weeks,” says Tilly. Also peculiar was that the number of healthy follicles wasn't decreasing markedly with age.

    Doctrine scrambled.

    A dividing germ cell in a mouse ovary may be producing new eggs.

    CREDIT: J. JOHNSON ET AL., NATURE 428, 145 (2004)

    Examining the ovaries, the researchers noticed roughly 65 cells in each that closely resembled fetal germ cells: the cells in a fetus that transform into either eggs or cells that produce sperm. Further tests confirmed that these cells were actively dividing and that they expressed a gene unique to germ cells.

    To see whether the germ cells were producing oocytes, Tilly's team performed another experiment. The researchers collected mice with cells engineered to express a green fluorescent protein. Then they grafted half of an ovary from a regular mouse onto each of the engineered animals' ovaries. After several weeks, green oocytes were visible in the transplanted ovarian tissue. The germ cells from one side of the ovary had migrated to the other, it appeared, and formed new egg cells.

    “This is almost like finding out that the world is actually flat,” says Kutluk Oktay, an infertility specialist at Cornell University's Weill Medical College in New York City. The work “challenges an entirely established concept, in a very elegant way.” Oktay says it could help explain mysteries he's encountered. He performed the first human ovarian tissue transplant, of tissue frozen from the same patient, that produced an embryo, as reported this week in The Lancet. The tissue has generated eggs for over a year so far, beyond what Oktay predicted based on the number of follicles detected in it prior to transplant. Perhaps, says Oktay, the frozen tissue harbored germ cells as well as intact oocytes.

    The Tilly lab's findings could shed light on why some cancer survivors emerge from treatment infertile but others don't; they might even enable more of them to have children. The team is investigating one possibility: The chemotherapy drug busulfan targeted dividing germ cells but not intact oocytes in mice; in humans, the drug has been linked to unusually high rates of infertility among cancer patients. If researchers can find ways to preserve some germ cells, or identify drugs that don't target them, Tilly suggests, fertility could be protected—even if existing oocytes are killed by treatment.

  5. NONPROLIFERATION

    New Initiatives Reach Out to Iraq's Scientific Elite

    1. Richard Stone

    As the coalition struggles to breathe life into Iraq's shattered scientific community, one of its top priorities is to nurture what had been one of Saddam Hussein's most valuable assets: researchers involved in weapons of mass destruction (WMD) programs. Officials are moving quickly to line up new work for the former weaponeers, often the cream of Iraq's scientific workforce, before they are tempted to apply their skills elsewhere. “The nonproliferation stakes are high,” says Carleton Phillips, a mammalian biologist at Texas Tech University in Lubbock who's on loan to the State Department and is now coordinating nonproliferation work across Iraq. “We have an opportunity to reduce the risk of expertise or material passing into the hands of terrorists or rogue states.”

    A trio of new initiatives that aim to keep weapons researchers busy is now taking shape. The Iraq International Center for Science and Industry (IICSI), expected to be established by the Coalition Provisional Authority later this month, intends to take the most talented researchers under its wing. Then the U.S. Civilian Research and Development Foundation (CRDF) this spring will bring a half-dozen top former weapons scientists to the United States for meetings aimed at forging international collaborations. And the U.S. National Nuclear Security Administration is bankrolling a broad effort to assess the equipment and facilities needed to renovate Iraq's shattered scientific infrastructure.

    Wicked flight of fancy.

    For 2 months Carleton Phillips bunked in Saddam Hussein's throne room, under this mural of Scud missiles.

    CREDIT: C. PHILLIPS

    The success of these nonproliferation efforts will hinge on assembling a realistic picture of Iraq's weapons programs. “There are still huge holes in our knowledge,” says a senior U.S. State Department official. Recent assessments suggest that fewer scientists were involved in such programs than had been thought, just 500 or so with “expertise that potentially is useful enough to be of concern,” says a coalition official. Although most of this top talent worked for military design bureaus, some were in academia. A handful of scientists remain in the custody of the Pentagon's Iraq Survey Group and will not be eligible for the nonproliferation programs for the time being.

    IICSI is being launched with $2 million in start-up funds from the provisional authority and is slated to receive another $20 million over the next 2 years. It aims to put top guns to work right away producing a road map for Iraq's civilian R&D. “This is a significant activity that does not require research facilities,” says the coalition official. That's a crucial point, he adds, given that “research facilities cannot be built overnight.” Meanwhile, Iraq's new science ministry (Science, 21 November 2003, p. 1307) will take charge of a few thousand former design bureau staff members who are deemed a less serious proliferation risk.

    Heading up the coalition's redirection program for weapons scientists is Alex Dehgan, a AAAS Diplomacy Fellow at the State Department (AAAS publishes Science). Dehgan is a biologist with a law degree who has studied lemurs in Madagascar and in the early 1990s helped revise Russia's environmental laws. Phillips, meanwhile, is no stranger to hot zones, having done fieldwork in Cuba, Nicaragua, and Chornobyl. “Still, nothing I've done before has been quite like this,” says Phillips, who relates some of his adventures in the current issue of Virginia Quarterly Review.

    Making a comeback?

    A fresh painting on a cement barrier outside Iraq's science ministry depicts an unmanned aerial vehicle (UAV), which the U.S. feared could have delivered banned weapons. The ministry wants to revive UAV development.

    CREDIT: COALITION PROVISIONAL AUTHORITY

    Phillips and Dehgan are working with CRDF to identify up to six senior Iraqi scientists who have been involved in weapons programs. CRDF plans to bring them to Washington, D.C., for a weeklong visit with top U.S. scientists and officials with an eye toward forging collaborations. “Hopefully this will be the start of many such visits,” says CRDF senior vice president Cathy Campbell. She adds that the foundation would like to include nonweapons scientists in Iraq in future initiatives. The program marks a radical departure for CRDF, which until this year had limited its operations to the former Soviet Union.

    The effort funded by the nuclear security agency, meanwhile, is being spearheaded by the Arab Science and Technology Foundation in Sharjah, the United Arab Emirates, and the Cooperative Monitoring Center at Sandia National Laboratories in Albuquerque, New Mexico. In this initiative, which got under way quietly in January, roughly 150 scientists, divided into teams, are visiting Iraqi institutes and academic facilities to assess infrastructure needs. “We're doing this for all scientists,” not just former weaponeers, says the foundation's president, Abdalla Alnajjar. The partners plan to hold a workshop somewhere in the Arab world in early May to brainstorm on urgent projects and line up donors.

    Some priorities are clear: Much work is needed to improve public health, clean up the environment, and reinvigorate agriculture using suitable seed stocks, to name a few. “These might seem like mundane activities for former WMD scientists,” but they're essential to rebuilding the nation, says the coalition official. Iraqi scientists are also expected to get better wired to the Internet soon. The provisional authority is restoring a sophisticated military fiber-optic network that was severely damaged during last year's invasion.

    Progress on all these fronts is likely to be slow. “Iraqi science is at least 12 and more likely 18 years behind the West,” says the coalition official. “We encourage senior Iraqi scientists to think in terms of being leaders for future generations.” But the rebuilding process has at last begun.

  6. BIODEFENSE

    U.S. Agencies Unveil Plan for Biosecurity Peer Review

    1. Jennifer Couzin

    Scientists were relieved to learn last week that the U.S. government is so far seeking only voluntary guidelines to control research and the dissemination of results that could conceivably aid bioterrorists. The announcement—by Tommy Thompson, secretary of the Department of Health and Human Services (HHS), and other top officials—responds to a report last year from the National Academy of Sciences that recommended this policy.

    According to a plan described by Thompson and officials from the National Institutes of Health and the White House, NIH will manage a new panel with 25 voting members, the National Science Advisory Board for Biosecurity, which will advise federal agencies and their grantees. “This is not intended to be a big-brother board that watches and penalizes,” said John Marburger, the White House science adviser, at the unveiling of the plan. Added Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland: “The goal is not to regulate.”

    Instead, HHS is following one main recommendation of a National Academies panel chaired by Gerald Fink, a geneticist at the Massachusetts Institute of Technology (Science, 17 October 2003, p. 368). The review grew out of worries that some research—on the transmissibility of pathogens, for example—could be used by terrorists. The Fink report advised scientists themselves to guard against the release of risky information. It also urged the government not to enact stringent laws and suggested that HHS set up a national advisory board. “As far as I'm aware, it's the first time that anyone's followed anything I've suggested,” jokes Fink.

    No big brother.

    HHS Secretary Thompson (third from left) and Zerhouni, Fauci, and Marburger (left to right) seek peer guidance.

    CREDIT: CHRIS SMITH/HHS

    The new biosecurity board, slated to be up and running by the summer, will have an annual budget of $2.8 million from unspecified sources. It will be charged with identifying types of research that might be misused, developing guidelines for local oversight bodies to monitor such research, and proposing procedures for communicating science at meetings and in publications. The board will not review individual research proposals, nor will it oversee classified research.

    The task of implementing the board's recommendations will fall heavily on the roughly 400 U.S. institutional biosafety committees (IBCs) created in the 1970s to review the risks of genetic engineering. Although IBCs weigh the dangers of research before work begins, they don't normally consider how resulting knowledge could be misused. Whether IBCs will have adequate resources to do this remains uncertain.

    Still, research leaders appear to be reassured by the HHS plan. “You're relying upon that ‘culture of responsibility’ approach. … The community believes in this,” says Janet Shoemaker, director of public and scientific affairs at the American Society for Microbiology in Washington, D.C. NIH Director Elias Zerhouni and Fauci point to NIH's Recombinant DNA Advisory Committee, which evaluates risk in gene-therapy studies at a national level, as a model for the new board. This paradigm suggests that “very little will be stopped” by the biosecurity board, says Gerald Epstein, a senior fellow for science and security at the Center for Strategic and International Studies in Washington, D.C.

    And that, argue some critics, is precisely the problem. The proposed board “falls dramatically short of what is needed in order to have a really effective biosecurity policy,” says Elisa Harris of the University of Maryland's Center for International and Security Studies in College Park. For one, she says, it doesn't cover privately funded research. Nor does she expect it to do much to harmonize international standards—an issue that needs to be addressed, according to the Fink report.

    Fauci, however, counters that “a code of conduct needs to be developed for scientists throughout the world.” And the new biosecurity board, he says, could be the one to craft it.

  7. ASTRONOMY

    Hubble Gazes Into the Universe's Uncharted Depths

    1. Robert Irion

    Amid controversy about its future in orbit, the Hubble Space Telescope has captured what may become its defining image: the Ultra Deep Field (UDF), the most sensitive photograph of the distant universe ever taken. The image, released on 9 March, contains about 10,000 objects—many of which probably existed when the cosmos was less than 1 billion years old.

    The telescope focused on a small square of the sky in the Southern Hemisphere for nearly 300 hours to create the photo, which is stunningly sharp even by Hubble's aesthetic standards. “It's gorgeous,” says project leader Steven Beckwith, director of the Space Telescope Science Institute (STScI) in Baltimore, Maryland. “The quality of the data, I believe, will be better than anything we've ever done with the space telescope.”

    Beckwith conceived of UDF as a way to delve beyond the original Hubble Deep Field, a 10-day-long exposure of thousands of remote galaxies. That 1995 image launched a new era of research into how galaxies evolve. But the image also tantalized astronomers with hints of the true building blocks of modern galaxies, just beyond Hubble's grasp at the time.

    Now, the telescope can detect those objects with its Advanced Camera for Surveys (ACS), installed 2 years ago by astronauts during the space shuttle's last service call to Hubble (Science, 22 February 2002, p. 1450). In addition to its crisper focus and wider field of view, the camera is sensitive to near-infrared light, the wavelengths at which the emissions of extremely distant galaxies—stretched by the expansion of space—shine most brightly.

    Hundreds of these beyond-red objects freckle UDF, which covers a patch of sky just 1/67th the size of the full moon. Astronomers who are trying to devise a coherent picture of how galaxies assembled after the big bang will focus most intently on those blotches, Beckwith predicts. “We're clearly seeing back to a time when the universe was chaotic,” he says. “Almost all of these are galaxies or things that will become galaxies, but we see a variety of unusual shapes that we can't yet identify.”

    Cosmic metropolis.

    The Hubble Space Telescope's Ultra Deep Field reveals about 10,000 galaxies in a tiny patch of the sky in the constellation Fornax, near Orion. Some objects date to just 800 million years after the big bang.

    CREDIT: NASA/ESA/S. BECKWITH (STSCI) AND THE HUDF TEAM

    STScI astronomer Sangeeta Malhotra and her colleagues used a “grism” on the Hubble camera—a grating that spreads light into its component colors—to gauge the objects' redshifts, a rough measure of their distance from Earth. The data verify that some of the objects shone when the universe was just 800 million to 1 billion years old. Unpublished results from a near-infrared spectrograph at the 8-meter Gemini South telescope at Cerro Pachon in central Chile suggest a similar range of ages, says astronomer Karl Glazebrook of Johns Hopkins University in Baltimore.

    Astronomers also scoured most of the UDF area with a Hubble camera and spectrograph whose vision extends further into infrared light: NICMOS, a cryogenically cooled instrument restored on the same shuttle mission 2 years ago. “Some of the most interesting results may come from objects that we see with NICMOS but not with ACS,” says astronomer Garth Illingworth of the University of California, Santa Cruz. Those objects could include protogalaxies that coalesced and started forming stars just 500 million years after the big bang.

    Beckwith expects astronomers to mine the rich UDF image in many other ways. For instance, a distant quasar shines within the photo. Analysis may reveal the size and shape of its host galaxy, details that aren't accessible to ground-based telescopes. Other astronomers plan to examine scores of UDF frames—taken at different times over a 4-month period—to search for faint moving objects in the Kuiper belt, the outer icy realm of our solar system.

    But UDF will make its true mark as a portrait of typical galaxies growing within a young cosmos. It's the best such image astronomers will have for at least a decade, says STScI astronomer Massimo Stiavelli. Astronauts would have installed another sensitive camera during their next visit to Hubble, providing a deeper look at UDF in infrared light than NICMOS allows. With NASA's cancellation of the servicing mission, that won't happen. “It's a big loss,” Stiavelli says. Still, he notes, “UDF will be one of Hubble's legacies for a long time.”

  8. OPTICS

    Lens Once Deemed Impossible Now Rules the Waves

    1. Kim Krieger

    For centuries, microscopes, eyeglasses, and magnifying glasses have slammed into a built-in limitation: No matter how good their lenses, the laws of optics dictate that details smaller than a wavelength of light are irretrievably lost. Undaunted, physicists have built a radically different breed of lens with the potential for perfect resolution. “It smashed the barrier; it crashed through the glass ceiling,” says John Pendry, a physicist at Imperial College London.

    The new lens, which George Eleftheriades and Anthony Grbic of the University of Toronto describe in an upcoming issue of Physical Review Letters, focuses microwaves—long-wavelength radiation that falls next to radio waves in the electromagnetic spectrum. By etching a flat plane of plastic with a wire grid studded with capacitors and inductors, the researchers created a material with a negative refractive index—one that bends waves in the opposite direction from normal materials. Because of transmission losses, lenses made from normal materials cannot distinguish objects less than half a wavelength apart, but “left-handed” (negative-index) materials can. The new lens, for example, resolves objects just one-sixth of a microwave wavelength apart.

    The left-handed lens achieves super-resolution by resurrecting waves that carry the subwavelength details of an object. Such so-called evanescent waves usually fizzle to nothing before they pass through a conventional lens. But the Toronto group's lens traps them like surf sloshing between two piers and amplifies them enough to reach the focal point (see diagram).

    Unnatural lens.

    Wire grid flouts optical limits by boosting trapped microwaves.

    CREDIT: GEORGE ELEFTHERIADES AND ANTHONY GRBIC/UNIVERSITY OF TORONTO

    The super-resolving lens is a significant proof of principle, Pendry says. In 2000, Pendry predicted that left-handed materials would make possible marvels such as completely flat lenses with perfect resolution and zero loss (Science, 10 November 2000, p. 1066). Some physicists thought such materials were physically impossible, but researchers soon created them and began working on left-handed lenses (Science, 19 December 2003, p. 2043). In February, physicists at the Institute for Theoretical and Applied Electromagnetics in Moscow announced a super-resolving lens, but their technique required the object to be almost touching the lens, making it impractical for real-life applications. The new lens overcomes that limitation.

    Eleftheriades dreams of applying the left-handed lens to medical imaging. “If you were to scale down to the frequencies of an MRI (20 megahertz), you could place the human body 1 meter away and still get super-resolution,” he says—a vast improvement over current instruments.

  9. ASTRONOMY

    Galactic Stripling Gives a Glimpse of the Universe's Raw Youth

    1. Charles Seife

    Redder is better, as far as astrophysicists interested in the early evolution of the universe are concerned. The more the light from a celestial object is shifted toward the red end of the spectrum, the farther away and older it is. Now astronomers claim to have found the most redshifted galaxy yet: more than 13 billion years old, a relic from an era when the earliest galaxies were forming.

    “We knew they were out there,” says Philip Solomon, an astronomer at the State University of New York, Stony Brook. The new discovery should help scientists figure out exactly how and when galaxies first came to be.

    About 400,000 years after the big bang, the universe was a hot cloud of neutral hydrogen gas. One billion years later, that gas had burned away, ionized by the bright light from stars and galaxies. Somewhere in between, those stars had to ignite and the galaxies had to coalesce. Although scientists have theories about how and when this happened, they had few hard data. That has all changed in the past few years, thanks, in part, to a phenomenon known as gravitational lensing. The immense mass of clusters of galaxies bends and focuses light like a telescope lens, allowing scientists to spot much more distant objects.

    Natural lens.

    Cluster Abell 1835 brought an ancient galaxy (circled, bottom) into focus.

    CREDIT: ESA, NASA, J.-P. KNEIB (CALTECH/OBSERVATOIRE MIDI-PYRÉNÉES), AND R. ELLIS (CALTECH)

    Such a lens helped a team of astronomers find the most ancient galaxy yet. Using the Very Large Telescope in Chile, they scanned the region of a well-known cluster of galaxies, Abell 1835, as they report in an upcoming issue of Astronomy & Astrophysics. Its lensing effect revealed faint and distant galaxies. Among the venerable crowd, one seems to have a “redshift” of 10—a measure of how fast the galaxy is moving and how far away it is—beating the previous record holder, at a redshift of 7. According to team member Daniel Schaerer, an astronomer at the Geneva Observatory, the image shows an extremely small galaxy when the universe was a mere 460 million years old. Most theorists think that small galaxies were forming around that time and eventually merged into bigger ones.

    California Institute of Technology astronomer Richard Ellis isn't sure the newfound galaxy is as far away as claimed, but he says there's no doubt that a current spate of high-redshift galaxies is shedding important light on the nature of the early universe. “They're giving us new information on how the earliest objects in the universe formed,” he says. “The overall idea is that these objects began to evolve, building up from small to big, and this is borne out by these observations.”

  10. SCIENCE PUBLISHING

    Japan Ponders Starting a Global Journal

    1. Dennis Normile

    TOKYO—Does a country need to publish its own internationally recognized journals to be a scientific power?

    Last month a group of Japanese scientists debated that question at a symposium* and wound up offering a tentative “yes.” Supporters argued that publishing a top-tier international journal in English would benefit efforts to disseminate the country's scientific achievements and strengthen Japanese scientists' ability to evaluate and communicate research results. But they readily admit that they have yet to address sizable logistical and financial hurdles that such an endeavor would entail.

    The meeting, sponsored by an ad hoc group and held at the high-level Science Council of Japan (SCJ), reflects growing concern about the health of the country's scientific publications. Japanese researchers and officials are proud of the growing number of Japanese papers in top journals overseas, and they note that the quality of an individual's publication record has become an important element in promotion and grant decisions.

    Shun-Ichi Murahashi, a professor emeritus of chemistry at Okayama University of Science and a member of an SCJ committee studying the issue, says that the Journal of the American Chemical Society (JACS), for example, has grown in the last decade in part by boosting the number of papers by Japan-based researchers. According to ACS, their share rose from 8.7% in 1997 to 11.6% last year. “Overseas journals seem to be expanding by including more Japanese papers,” Murahashi says. Over the same period, the number of Japanese authors on research papers in Science has grown by roughly half, although the overall number of published papers has held steady.

    Beyond paper.

    Kiyoshi Kurokawa says that any new Japanese publication should be electronic.

    CREDIT: D. NORMILE

    But some scientists believe that those developments mask an alarming decline in the health of Japan's own scientific publications. The English-language Journal of the Physical Society of Japan lost one-third of its subscribers during the 1990s, Murahashi says, and experienced a comparable decline in the number of papers published and their impact factor. Similar trends are occurring at most Japanese journals.

    Murahashi welcomes the growing number of Japanese scientists on review boards and in editorial positions at foreign journals. But the decline of domestic journals, he warns, shrinks the country's pool of research “assets.” “It's quite clear that we need to start our own international journals,” he says.

    Some speakers believe that a Japan-based international journal would also result in a fairer shake for Japanese and Asian researchers. Ryoji Noyori, a 2001 Nobel laureate in chemistry who leads the Institute of Physical and Chemical Research (RIKEN), says that “the review process at foreign journals is a black box” for many Japanese scientists, and he and others say they still hear occasional complaints about reviewers poaching research results before the paper has been published.

    Kiyoshi Kurokawa, a professor of medicine at Tokai University and current SCJ president, is wary of such claims. He suspects that they date from decades ago and no longer reflect current practice. Instead of complaining, he urged those interested in starting a new journal to first understand “why Nature and Science have survived and have readers willing to pay for their subscriptions.” Both journals, he says, have earned a reputation for fairness and excellence.

    Successful screen test.

    Western readers are flocking to an online portal offering scientific material from 140 Japanese organizations.

    SOURCE: JAPAN SCIENCE AND TECHNOLOGY AGENCY

    If Japan decides to start such a journal, he suggested that it be electronic. He pointed to the popularity of J-STAGE (for Japan Science and Technology Information Aggregator, Electronic; http://www.jstage.jst.go.jp/), a portal that provides access to the publications and news of more than 140 Japanese societies. Each society determines what content will be available through J-STAGE, which is operated by the Japan Science and Technology Agency (JST), an affiliate of the Ministry of Education, and whether any restrictions should apply. In addition to making the material more accessible domestically, J-STAGE has greatly increased the foreign readership of Japanese journals. The print version of Cell Structure and Function, published by the Japan Society for Cell Biology, had a 97% Japanese readership, he notes, whereas 92% of the readers of the online version—with free and full access—are from overseas.

    Whether electronic or print, a new journal will be expensive. Koichi Kitazawa, executive director of JST, shocked the audience by estimating that an $18 million annual subsidy would be needed to create an interdisciplinary, international journal. His estimate, which includes some sort of incentive plan to support successful research teams, is intended to send a message “to people who think that it is possible to launch such a journal easily.” And whereas RIKEN's Noyori believes that “strengthening the dissemination of scientific information” should be a government priority, Tokai's Kurokawa would prefer to see the journal pay its own way.

    Supporters of the idea haven't yet asked the government for money. But one of the science community's best friends in the diet (legislature) has already signaled his support for the idea. “I recognize the need to strengthen Japan's efforts to broadcast Japanese research results to the world,” Koji Omi told participants. As an added boost, Omi also proposed that granting agencies give greater weight to domestic publications when deciding which scientists to fund.

    • * “Strengthening Global Information Dissemination Capabilities,” Tokyo, 27 February 2004.

  11. CLIMATE CHANGE

    All Downhill From Here?

    1. Kevin Krajick*
    1. Kevin Krajick is a writer in New York City.

    Biologists say climate change may already be affecting high-mountain ecosystems around the world, where plants and animals adapted to cold, barren conditions now face higher temperatures and a surge of predators and competitors

    Pikas are the essence of cuteness: The miniature, pink-eared cousins of rabbits nibble on flowers, greet visitors with high-pitched squeaks, and scamper like curious chipmunks. They are also some of the world's toughest mammals, dwelling beneath boulder piles on high, treeless peaks where winter winds howl most of the year and the herbage of brief summer is too scant to attract lowland competitors.

    Pikas thrive where it's cold and bare. So it's no surprise to some biologists that, as global temperatures rise, the pikas' numbers are nose-diving in far-flung mountain ranges.

    Alpine ecosystems are particularly vulnerable to climate change, and recent studies suggest that mountain dwellers—from delicate flowers in the Swiss Alps to pygmy possums in Australia—are in trouble. Although it can be difficult to tease out other factors, including fire suppression and livestock grazing, a growing number of researchers fear that if the heat keeps rising, many alpine plants and animals will face quick declines or extinction.

    “People always thought the whole world could go to hell, and pikas would be fine. Actually, they may be canaries in the coal mine,” says wildlife biologist Andrew Smith of Arizona State University in Tempe.

    Initial findings have prompted a surge of studies of the alpine—the high windswept regions above the timberline—and researchers are beginning to coordinate their efforts. They are finding that creatures everywhere are responding to warming, but mountain biota, like cold-loving polar species, have fewer options for coping (Science, 19 January 2001, p. 424).

    Global average temperatures have increased by 0.6°C in the past 100 years, and they could go up another 1.4° to 5.8° in the next 100. In an apparent bid to adjust, many creatures have shifted flowering, breeding, or migration dates; mobile ones such as butterflies and birds have moved ranges poleward an average of 6.1 kilometers per decade since the 1960s, according to an analysis of 1700-some species published last year in Nature (2 January 2003, p. 37).

    High-mountain biota are trapped, however, and those living in the alpine are in the tightest corner of all. Comprising just 3% of the vegetated terrestrial surface, these islands of tundra are Noah's ark refuges where whole ecosystems, often left over from glacial times, are now stranded amid uncrossable seas of warm lowlands.

    These islands are shrinking. The lowest elevation at which freezing occurs in mid-latitude mountains has climbed 150 meters since 1970. (On average, each rise of 100 meters in altitude corresponds to a 0.5°C drop in mean temperature.) This appears to be hastening local extinctions that have been proceeding slowly since the last glacial age. Fossils show that pikas, for example, once ranged widely over North America but have contracted to a dwindling number of high peaks during warm periods of the last 12,000 years, says U.S. Geological Survey (USGS) ecologist Erik Beever.

    Tundra at the top.

    Islands of alpine vegetation are sprinkled across high peaks.

    CREDIT: NEIL RABINOWITZ/CORBIS

    Alpine creatures are poor dispersers, anyway. With slowed life cycles, many plants reproduce by cloning, not by seed, and the tiny pikas rarely roam more than a kilometer to find new homes. Many species have been isolated on the same mountains for so long that they have become new species. Mountains are rich in endemics as well as total biodiversity, because they contain many slopes, aspects, and elevations that compress abundant microclimates and specialized habitats into small areas. “A lot of populations are just little frostings on peaks,” says James Brown, a population ecologist at the University of New Mexico in Albuquerque who studies alpine mammals.

    These small populations can be pushed out by any number of temperature-driven forces: invasions of trees, lower-elevation plants, or predators; frequent extreme weather events; and, perhaps in the case of creatures such as pikas, simple overheating. “Take a mountain and warm it up, and maybe [alpine ecosystems] shift upward—but only until they reach the top,” says Brown.

    Headed to heaven

    The first danger signs have come from plants. About 80 to 100 years ago, European botanists inventoried plants on many summits in the Alps. In 1994, researchers from the University of Vienna showed that on more than two-thirds of the sites resurveyed, grassland species from lower slopes had crept up as much as 4 meters per decade—an apparent response to a 0.7°C regional warming. If the ascent continues, says study leader Georg Grabherr, cold-loving plants at the highest elevations will be pushed upslope and in the end “go to heaven.”

    These plants include rarities such as Arenaria tetraquetra, which clusters near summer snow patches that provide dribbles of meltwater. “They're fantastic,” says Grabherr, describing the plant as “a round cushion with little white flowers on the margin, exactly like a halo—so they are ready for paradise.”

    Grabherr says that based purely on rising temperatures, invaders should be climbing slopes twice as fast as they are. But, he adds, “alpine plants take a long breath before doing anything,” so it could take 40 or 50 years for more dramatic responses. His results are bolstered by colleagues who include Martin Camenisch, a botanical consultant in Chur, Switzerland. He says that in the past 80 years, common newcomers have invaded one 2800-meter mountaintop from the lower slopes, nearly tripling species richness—and occupying up to 20% of the space formerly held only by high-alpine species.

    To track projected changes, Grabherr has organized 40-some scientists into the Global Observation Research Initiative in Alpine Environments (GLORIA, at http://www.gloria.ac.at/). With identical inventory plots and protocols, collaborators have agreed to return for surveys every 5 to 10 years and feed results into a central database. Seeded by money from the European Union, scientists launched GLORIA in 2001 on 71 summits from Spain to Russia, and they have since added sites in Australia, the United States, and South America.

    The most vulnerable places are ones where mountains are low and climate is temperate, so there is little alpine to begin with. These include Greece's Mount Olympus and Spain's Sierra Nevada range, where only 200 to 400 meters separate timberlines from summits. In Australia, only 11,500 square kilometers of mountain terrain even get winter snow, and just a fraction of that is true treeless alpine. Crammed here are mountain pygmy possums, specialized reptiles (including two that have just been described), and countless undescribed invertebrates. A 30% decline in snow cover over the past 40 years has allowed feral cats, rabbits, and foxes to move in, says ecologist Ken Green of the Australian National Parks and Wildlife Service; native species are plummeting. “There is no opportunity for altitudinal shift—everything is already at the limit,” he adds.

    In neighboring New Zealand, a paper last year in Arctic, Antarctic, and Alpine Research predicts that a 3°C temperature rise over the next century—moderate as estimates go—will wipe out 80% of alpine islands and extinguish a third to a half of 613 known alpine plants. Co-author Alan Mark, a botanist at the University of Otago in Dunedin, New Zealand, says that even if temperatures stop rising now, 40 to 70 species will be at risk in coming decades, as ecological shifts catch up with already-milder conditions. “There is no question of if—just when,” he says.

    Trees on the move

    Since the alpine is by definition treeless, rising timberlines themselves could trigger much change, and that is apparently already under way in some places. Christian Körner, a botanist at the University of Basel in Switzerland, argues in an upcoming paper in the Journal of Biogeography that tree lines everywhere are controlled by a surprisingly narrow range of root-zone temperatures; trees stop where the mean drops to about 6.5°C. Indeed, Russian researchers writing in Ecological Studies last year reported that in the Ural Mountains, temperatures have gone up as much as 4°C during the 20th century and trees have moved 20 to 80 meters upslope, reducing alpine zones by 10% to 30%.

    Tree rings reveal similar upward marches in the Alps, says Jean-Paul Theurillat, a phytogeographer at the University of Geneva, Switzerland. At around 1800 meters, trees average 140 years, but they are younger higher up, until at 2700 meters they average only 16 years. Infilling since the mid-19th century is visible from British Columbia to Montana. Near Banff National Park in Canada, alpine firs and Engelmann spruces have moved 50 or 60 meters upslope just since 1990, report researchers from the University of Alberta in Edmonton.

    Not at their peak.

    Warming may threaten alpine creatures such as the pika (left) and plants such as Arenaria tetraquetra (right).

    CREDITS: (LEFT TO RIGHT) R. J. FRANKEN; PAULI HARALD/GLORIA

    However, Körner and others say that timberline movements are not as straightforward as meets the eye, and tying them unequivocally to a single factor such as global warming is misleading. For one, trees grew higher up before the Little Ice Age, a cold period lasting into the early 1800s; some trees may just now be readvancing rather than responding to more recent warming. Fire suppression may also be allowing some forests to advance to higher elevations. At Montana's Glacier National Park, ecologist Dan Fagre of USGS points out that much new growth is not actual elevational advance; rather, he says, it is infilling of meadows between outlying fingers of conifers, as well as new vigor in small stems once twisted like shrubs and now straightening up. This may presage a real advance, but Fagre contends that increased moisture, not temperature, may be the primary driver.

    Temperature and moisture have complex relations in mountains, says Lori Daniels, a dendrochronologist at the University of Colorado, Boulder. In a paper in press at Ecology, she shows that high-altitude deciduous trees in Patagonia have advanced since a round of warming starting in the 1970s—but in the hottest years, growth has declined, because it is too dry. “We thought we understood how temperature works, but once you add in other factors it gets more complex,” says Daniels.

    In any case, where trees do appear, they change everything. For instance, alpine butterflies feed on alpine plants, and once they are crowded out, both disappear. Now it is becoming clear that even a few trees can dangerously fragment habitat, says ecologist Stephen Matter of the University of Cincinnati, Ohio. That's because alpine butterflies need constant sun to warm flight muscles, and shade from even modest fingers of trees dissecting their territory literally knocks them out of the air. In a paper in press at Ecological Applications, Matter shows that in some Canadian study sites, more than 90% of migrating Parnassius smintheus butterflies en route to nearby meadows die when they hit intervening trees, a mortality rate that could cause domino-effect local extinctions. P. smintheus is not yet rare, but close relatives in Europe are already on threatened lists.

    Groundhoglike marmots need treeless terrain for a quite different reason—to see predators coming—and they also are disappearing. The endemic Vancouver Island marmot, declining for decades (or maybe centuries) with the apparent advance of trees into high meadows, is now one of the most endangered mammals in the world, with 21 known wild individuals left. Andrew Bryant, chief scientist at the Marmot Recovery Foundation in Nanaimo, British Columbia, blames wolves and cougars that travel up new logging roads cut at lower elevations, then sneak up on marmots using saplings as cover.

    A similar decline may be taking place among the endemic Olympic Peninsula marmots of Washington state, where trees, followed by coyotes, are proliferating. However, wildlife biologist Suzanne Griffin of the University of Montana in Missoula cautions that studies there are just starting, so it's too soon to be sure of the culprit.

    The case may be clearer for pikas, which are directly, exquisitely sensitive to temperature. Hyped-up body heat helps them survive cold, but apparently they cannot turn it down. In the 1970s, Arizona State's Smith gave a graphic demonstration of this by removing pikas from the cool talus interstices where they hide between daytime foraging expeditions and caging them outside. They died after just a morning in ambient shade temperatures as low as 25.5°C. “They don't have much flexibility,” says Smith, who admits he would not do such an experiment now, given heightened awareness of animal rights, never mind declines in pikas.

    USGS's Beever, who published a study in the Journal of Mammalogy last year, says American pikas have recently winked out at nine of 25 historically known localities, and he points to rising temperatures as the prime suspect. He says heat could kill directly, change the composition of plants the animals eat, or—most likely, in his view—force pikas inside so that they cannot get enough to eat.

    Some of the American pika's cousins elsewhere also appear to be in decline. For example, in 1986, a biologist at the Xinjiang Academy of Environmental Protection named Li Wei-Dong described a new species, the Ili pika, in the Tian Shan mountains of northwest China. But when he went back in 2002 and 2003, he saw not a single specimen in 250 kilometers of foot-and-horseback trekking. In a paper submitted to the journal Oryx, he blames ongoing warming, possibly compounded by herders and their dogs as they range higher now that glaciers are retreating and lofty pastures are greening up.

    Vulnerable.

    Marmots, like these from Olympic Peninsula in Washington state, are declining too.

    CREDIT: DARRELL GULIN/CORBIS

    In the Yukon, University of Alberta wildlife biologist David Hik documented a 90% decline in collared pikas during the winters of 1999 and 2000, when decades of warming culminated in bizarre midwinter snowmelts, rain, and refreezing. Because pikas stay active all winter under snow, this series of events may have removed insulation even they require, then iced over forage. Alpine ground squirrels collapsed too, their burrows flooded. “Consistent with climate-change models, extreme events like this will happen more and more,” says Hik, who has a paper in review at the Canadian Journal of Zoology. “These animals are made for extreme conditions, but there are thresholds. Then it starts to look pretty serious for them.”

    All the same, it's hard to completely rule out other causes for the vanishing pikas. Montana sites that still have pika-friendly weather have also seen extinctions, reports biologist Christine Ray of the University of Colorado, Boulder, who suspects disease. “It's still a mystery,” she says.

    Alpine aquatic systems are showing changes, too, although not yet declines. Aquatic ecologist David Schindler of the University of Alberta says that in the lower Canadian Rockies, warming summers have so far simply speeded plankton life cycles and made alpine fish grow bigger. “Most people probably think it's good to have bigger fish,” says Schindler, but experiments show that cold-water trout die off once temperatures pass a threshold. The same goes for specialized invertebrates such as caddis flies that live in icy glacial melt streams.

    Fagre of USGS points out that glacial retreat is by far the most visible result of mountain warming: Two-thirds of the glaciers present in Glacier National Park in 1850 are already gone, and the rest could disappear by 2030. This means, he says, that alpine stream temperatures could soon shoot up and summer flows might cease altogether, wiping out much invertebrate habitat.

    A less visible effect is that fast-wasting glaciers are releasing pulses of contaminants such as polychlorinated biphenyls and insecticides. Such contaminants evaporate from soils and waters in industrial lowlands and drift off—until they hit mountains, where they condense in rain or snow and fall back down, says Jules Blais, a geochemist at the University of Ottawa. This long-distance conveyor is harming polar bears and poisoning human breast milk in the Arctic, and it also appears to be working in alpine environments just below glaciers, notes biologist John Elliott of the Canadian Wildlife Service. Sediments in glacially fed high lakes are being found with up to 1000 times more pollutants than those at lower elevations, and fish have developed levels that could threaten bald eagles and other avian predators.

    In the short term, not all changes may be bad—at least not in the highest mountains, where there's still room to go up. There, new frontiers are opening in the barren spaces left by the retreat of still-vast glaciers. During the past 5 years, an interdisciplinary team has been following the quick advance of alpine life into newly ice-free zones in the Peruvian Andes near the huge Quelccaya ice cap. At 5250 meters, the team members have counted 54 alpine plant species and 23 species of lichens—“a definite increase” for a place that was near a towering ice front just a century ago, says Anton Seimon, a geographer at Columbia University's Earth Institute.

    In newly melted ponds at 5372 meters, the team members have found tadpoles (the world's highest known amphibians) and, on newly exposed ridges, upwardly mobile herds of vicuña, rare cousins of the llama. Indigenous people are close behind, planting crops at ever-loftier elevations. “There's a shortage of arable land. Here, this might be a good thing,” says Seimon. Beyond the newly settled biotic zones, craggy glaciated peaks and the vast Quelccaya still roll to the horizons, unconquered by life, except perhaps for microbes beneath the ice. At least for the moment, it is hard to imagine that someday all this could melt away, and the pioneers, like the ice itself, might go to heaven.

  12. SPACE EXPLORATION

    Moon's 'Abundant Resources' Largely an Unknown Quantity

    1. Charles Seife

    Will we find enough raw materials, in accessible enough places, to power Bush's proposed lunar base?

    It's 2014. Forty-five years after the Apollo 11 landing, humans return to the moon to set up the lunar base that President George W. Bush proposed a decade earlier. Which will they be: homesteaders or campers?

    Apollo astronauts, who roved the lunar surface for tens of hours, could easily bring with them enough food, water, and air for a short visit. Under NASA's ambitious new plans for lunar exploration, however, astronauts will live on the moon for weeks or months at a time—and the longer they stay, the more difficult and expensive it becomes to supply them from Earth. Some space boosters, the president included, suggest that part of the solution lies in living off the land. “The moon is home to abundant resources,” Bush stated in his 14 January speech announcing NASA's new vision. Scientists agree that potentially useful chemicals, such as water ice and various gases, are indeed locked up in lunar soil. But when it comes to estimating how abundant they are and how practical it would be to extract them, one resource still in short supply is information.

    Water. More valuable than gold to a lunar base, water can be used for drinking or it can be split to create oxygen to breathe—or oxygen and hydrogen for rocket fuel. A few tons of hydrogen-oxygen fuel could send a rocket off the surface of the moon and into space. That's why moon buffs such as Paul Spudis, a planetary scientist at Johns Hopkins University's Applied Physics Laboratory in Laurel, Maryland, think the most important lunar resource is likely to be water from ice.

    In theory, ice from crashed comets may linger in cold, dark niches at the lunar poles, from which it could relatively easily be extracted and distilled. But scientists disagree about how much of it is trapped there. In 1996, a Department of Defense satellite called Clementine bounced radar waves off the moon's surface and back to radar telescopes on Earth. Spudis and colleagues noticed that reflections from shadowy nooks near the lunar south pole could be interpreted as signatures of multiple scattering within crystals of water—an indication that about 1.5% of the lunar soil in those regions is water ice.

    Similar results came when the Lunar Prospector satellite, launched in 1998, used a spectrometer to count neutrons bouncing off the moon in energy ranges known to interact with hydrogen—presumably in water ice. The answer: Patches of polar lunar soil were about 0.5% to 1% ice by weight—less water than Clementine found, but still enough to make a polar base attractive.

    Orb of plenty?

    Titanium minerals mapped by the Clementine orbiter (red areas) may contain useful amounts of oxygen and helium.

    CREDIT: CLEMENTINE/NASA

    On the other hand, Donald Campbell, a physicist at Cornell University, and colleagues twice bounced radio waves off the moon from the Arecibo telescope in Puerto Rico but saw no signs of water ice. “We don't believe that the radar data supports” the large amounts of ice that the Clementine analysis would imply, Campbell says. And when the Lunar Prospector crashed into the moon's south pole at the end of its mission, scientists didn't see water in the resulting plume of debris. Spudis thinks a more energetic crash would have splashed up water vapor, but for now, lunar water remains an open question.

    Trapped gases. Even if there's little water on the moon, astronauts might be able to make it and other useful chemicals from more-abundant raw materials: light elements such as nitrogen, oxygen, and carbon, manufactured by nuclear fusion inside the sun and blown to the lunar surface on the solar wind. These trace elements are present in the lunar soil, or regolith, at levels of parts per million, so it would take a huge amount of mining to get usable quantities. The good news is that they are extremely easy to extract: Just heat soil up (using the base's solar or nuclear power source) and the gases escape, yielding nitrogen, carbon monoxide, carbon dioxide, methane, and hydrogen that can be converted into air or water. Water, in turn, can be used to strip oxygen from a common iron-titanium lunar mineral known as ilmenite.

    Helium. Even more valuable in the long run may be a much rarer legacy of the solar wind, helium-3. Only Earth-bound humans would benefit, however, and even its enthusiasts acknowledge that it's a long shot.

    Helium-3 is attractive because it can fuel an advanced fusion reactor. A helium-3 atom combined with a hydrogen-2 (deuterium) atom or with another helium-3 releases a great deal of energy with relatively little radioactive waste. “If we replaced all the electrical power plants in the United States with [helium-3/deuterium] reactors, you'd need only 40 metric tons to produce all the electricity needed in 2004,” says Gerald Kulcinski, a physicist at the University of Wisconsin, Madison. Only a few hundred kilograms of helium-3 are accessible on Earth, he says, but the lunar regolith harbors millions of tons of it.

    Several factors make mining helium-3 a dicey proposition. For one, most of the solar wind strikes the lunar farside, which faces the sun when the moon's orbit takes it upwind of Earth's magnetic shadow. But ilmenite, the only lunar mineral that traps helium-3 effectively, is more common on the moon's nearside. Wherever it crops up, even helium-3-rich lunar soil won't contain much of the gas. “It'll be a little better than 10 parts per billion by weight,” says Timothy Swindle, a geochemist at the University of Arizona in Tucson. “To make a dent in the world's energy needs, you're going to have to mine a large fraction of the surface of the moon.” Physicists will also have to create a working helium-3 reactor—no easy task, considering that decades of research have yet to produce a fusion power plant of any sort. And, of course, someone will have to ship all the helium back to Earth.

    The bottom line: Before investing in helium futures or moon air and water rights, wait for scientists to figure out how much of these resources there are and where they reside. NASA's 2005 budget contains money to begin exploring the moon with robot missions—including, presumably, prospectors. Their work will reveal whether visiting astronauts will be able to eke out an existence from the lunar soil, or whether the rest of us will have to foot a literally astronomical delivery bill.

  13. EMERGING INFECTIOUS DISEASES

    A Global Fire Brigade Responds to Disease Outbreaks

    1. Martin Enserink

    As novel pathogens erupt with increasing frequency, the World Health Organization is taking a new leading role in stamping them out

    GENEVA—Klaus Stöhr does not seem to be enjoying himself—even though it's his birthday. Looking pale and almost gaunt at 8:30 on a Friday morning, Stöhr sighs as he sits down for the first of several daily meetings. The topic, as it is every day lately: the avian influenza outbreak that's sweeping through Asia.

    Swiftly, Stöhr and a dozen colleagues at the World Health Organization (WHO) Headquarters here run through today's action points. Can WHO provide guidance for the treatment of human patients? That's difficult, Stöhr says. Clinical information about the more than two dozen patients so far is limited; many have died and have been buried before samples could be taken. “It's very frustrating,” Stöhr says. Next: What's the latest with development of a vaccine? How many antiviral tablets are currently available for those culling chickens? Can somebody rapidly produce a chronology of the outbreak, which a New York Times reporter has requested?

    Although far removed from the Asian poultry farms where the H5N1 virus is raging, WHO has become the world's nerve center for the battle against avian influenza—and, for that matter, any other newly emerging disease. Since 2000, WHO's department of Communicable Disease Surveillance and Response (CSR) has coordinated a global network of labs and other organizations dedicated to stopping infections. Together, they act as a planetary fire brigade, constantly on the lookout for outbreaks and ready to fight them before they spiral out of control.

    That's a far cry from the situation of 10 years ago: Typically, a multitude of agencies would join the fray when a disease broke out, usually without much coordination. It's also a big transition for WHO, says Stöhr's colleague Mike Ryan, who manages the global outbreak response. Traditionally seen as a “bunch of shiny-arsed administrators in Geneva” focused on science but aloof from the chaos on the ground, the agency has now taken a more hands-on approach, says Ryan.

    But in the age of globalization, when each new pathogen is just a plane ride away, the shift to a global system was inevitable, experts say. And they add that last year's severe acute respiratory syndrome (SARS) outbreak demonstrated that WHO can handle the job. “They've earned a lot of new respect with that,” says C. J. Peters of the University of Texas Medical Branch in Galveston. “I hope they can keep it, because we'll need them more and more.”

    War room.

    At WHOHeadquarters experts huddle daily to exchange information on the latest disease outbreaks.

    CREDIT: P. VIROT/WHO

    The idea for a global disease watchdog arose during the 1990s. Until then, the approach was a bit haphazard. Rich countries organized their own control efforts when a disease erupted unexpectedly; poorer nations often called in foreign agencies such as the Pasteur Institute or the U.S. Centers for Disease Control and Prevention. (CDC's fieldwork on new and scary microbes is legendary.) But many other parties flocked to outbreaks as well, creating confusion over who was doing what.

    Many cite the 1995 Ebola outbreak in Kikwit, the Democratic Republic of the Congo (formerly Zaire), as an example. More than a dozen different groups—including CDC, WHO, aid workers, and academic researchers—descended on the city, but nobody was in charge, logistics were chaotic, and rivalry hampered control efforts. The same was true for the 1997 Rift Valley fever outbreak in East Africa, says Ray Arthur, CDC's associate director for global health: “It was clear there had to be a better way of doing business.”

    Many credit Ryan—a burly, outspoken Irish epidemiologist and self-described “field animal”—as the driving force behind the coordination efforts. In 2000, those efforts culminated in a seminal meeting in Geneva, where representatives of 67 institutions—from labs and university departments to charities—created the Global Outbreak Alert and Response Network (GOARN) to direct their activities during future outbreaks. The CSR office in Geneva was to become its global headquarters.

    During an outbreak, time is critical, so WHO also set up an early-warning system. Today, a group of about 40 people in Geneva continually scans outbreak reports, however vague, for items that might warrant a closer look. Some 50% of the 10 to 20 daily leads come from a software system developed by Health Canada that constantly trawls news sources in six languages on the Internet for outbreak stories.

    Most reports—say, an outbreak of food poisoning in a nursing home—need little follow-up. But some set off alarms, such as the January encephalitis epidemic in Bangladesh, primarily among young boys. In that case, WHO dispatched a team of experts, drawn from its own staff and the GOARN network, to investigate the disease. (CDC lab studies confirmed that it was an outbreak of the Nipah virus.)

    The network was thrown into action almost immediately after it started—during the 2000–01 Ebola outbreak in Uganda, the largest ever recorded. “We worked an awful lot of gremlins out of the process,” Ryan says. Actions in subsequent outbreaks—of a meningitis strain called W135 in Burkina Faso, for instance, and Ebola in Gabon and the Republic of the Congo—helped iron out more of the problems. Last week, GOARN members were meeting in Atlanta to review recent outbreak responses and draw up plans to expand the network.

    Although CDC is still a major player in many outbreaks, today, when the U.S. behemoth enters a country for fieldwork, it usually does so under WHO's flag rather than its own, says Arthur, who acts as the agency's liaison to WHO. The imprimatur of a United Nations agency often makes things easier, he says, and what's more, WHO can provide logistics, such as telecommunications and transportation, and it is experienced in safeguarding security in unstable areas.

    The GOARN network again proved its mettle during the SARS outbreak, notes virologist John Mackenzie of the University of Queensland, Australia. “Without it, I think the response would have been abysmal,” he says. But last year's crisis also showed that the network's backup in Geneva was very thinly stretched. Overwhelmed and understaffed, people put in yeoman's hours; many felt stressed or burned out. When it was all over in July, “we were left with a human-resource wasteland,” Ryan says.

    In one way, it's déjà vu with the bird flu outbreak: Lunch hours have fallen by the wayside in Geneva, as have weekends and vacations. But “this time, things immediately clicked into place. We're working much more according to plans,” Ryan says. Thanks to SARS experience, the agency had also built up an intensive working relationship with some of the countries, such as China, Vietnam, and Thailand, that are struggling with bird flu. Stöhr, who spent years preparing for flu but took on the SARS job last year, is again the principal scientist involved.

    The SARS episode also marked the beginning of a much stronger presence by WHO in the media. Even before SARS, the media-savvy former director-general of WHO, Gro Harlem Brundtland, had started expanding the communications staff; once the disease erupted, teleconferences were held almost daily, and WHO's formerly dull Web site was continually updated with fresh information.

    Hot seats.

    Klaus Stöhr (right) is WHO's principal flu scientist, and Mike Ryan (left) manages outbreak responses.

    CREDITS: P. VIROT/WHO

    Some staffers shunned the limelight. “This was seen as a quiet little place where people did their technical work,” says media officer Dick Thompson, a former Time reporter who joined WHO in 2001. “SARS has dragged them into the sun.” But the move has helped the agency project a more self-confident, can-do image.

    Still, WHO faces several challenges in this new role. For one, it doesn't always have access to countries at critical moments—a major obstacle during last year's SARS crisis, when observers saw China as trying to sweep its outbreak under the rug. That could change, however, with a new treaty hatched within CSR years ago. The International Health Regulations, adopted in 1969, require countries that experience outbreaks to take several steps to protect the rest of the world. But there's wide agreement that the text is outdated—for instance, it covers only plague, cholera, and yellow fever. Although CSR has been trying to revise the treaty for years, it was slow going—until the SARS outbreak, and China's initial denials, opened the world's eyes to the necessity of stricter rules. A new text may be adopted by the World Health Assembly in 2005.

    CSR also desperately needs more resources. Putting in overtime “is part of the deal here,” Ryan says—but in the long run, he adds, the agency needs to be able to sustain its response without exhausting its own staff.

    Part of the problem, some say, is that the top brass at WHO aren't supportive enough. “There seems to be a lack of recognition [of the network] within the hierarchy,” says Mackenzie. But CSR director Guénaël Rodier says he cannot complain about a lack of support. The problem, he says, is that getting more money from WHO is difficult because there are many competing programs. Moreover, some 60% of its $1 billion budget is given by donors, such as Western countries, directly to WHO programs, and they're often more interested in spending money on development than on outbreak control, Rodier says. Instead, he is seeking support from major corporate sponsors in hope that they will see it's in their own interest to contribute. “We can limit the disruption from outbreaks, and disruption is very bad for business,” says Rodier.

    Crisis control

    Until that support comes, life here is likely to be frenetic. There's always an urgent document to send out, some minor crisis to address.

    Stöhr, for one, is spending part of his birthday trying to limit the diplomatic fallout from a news story. At a press conference earlier in the week, he told reporters that the current bird flu strain had been found in samples from a year ago, showing that the virus had been around for a while. Based on its own sources, New Scientist concluded that those samples came from China and alleged a cover-up by the Chinese government. Not true, Stöhr asserts; the samples came from another country and were only recently tested. But China immediately issued an angry denial, and Stöhr is worried that WHO could get blamed for precisely the type of country bashing it seeks to avoid.

    Later that Friday, there's another daily flu meeting; this time WHO's people in the field in China, Vietnam, and Thailand are on the speakerphone with updates. The culling operations are a constant cause for concern; they're key to stamping out the virus, but without careful protective measures, they also expose people to the virus, putting them at risk of disease and increasing chances that a human and an avian strain might mix to create a new pandemic virus. “Are we fueling the pandemic engine?” Stöhr asks.

    Then, after some crackling sounds and a strange melody, there's the voice of a WHO representative in China. “We have some breaking news here,” she says. “We have outbreaks in three more provinces.” The group absorbs the news quietly; then Stöhr stresses that WHO would like to see samples from each affected country as soon as possible. Checking whether the same strain is circulating everywhere is essential for producing an effective vaccine, he says.

    Ryan, a strong believer in short meetings, quickly moves through the rest of the agenda. “Au revoir, and see you on Monday,” he says. “Let's hope things stay quiet.”

  14. PLANT BIOLOGY

    Remembrance of Winter Past

    1. Jean Marx

    Many crops keep track of the cold weather they've experienced and then bloom rapidly in springtime. A spate of new gene discoveries hints at how they stay on schedule

    From Proust's madeleine-sparked reminiscences on his youth to the mental gymnastics of a bridge player trying to count out her opponents' hands, we're all familiar with human memory abilities. We don't expect plants to perform similar feats. But some plants, including biennials that require two growing seasons to flower and set seed, are able to remember that they have experienced prolonged exposure to cold. Only then will they flower in spring—an agronomically important adaptation known as vernalization that prevents premature flowering.

    How plants do this has been a mystery, but now researchers are getting a handle on the genes underlying vernalization. On page 1640, a team led by Jorge Dubcovsky of the University of California, Davis, identifies a gene required for vernalization in winter wheat. The gene, called VRN2, encodes a protein that represses flowering. Prolonged cold exposure shuts down VRN2 activity, after which the wheat plants can flower.

    Other groups, including Richard Amasino's at the University of Wisconsin, Madison, and Caroline Dean's at the John Innes Center in Norwich, U.K., have identified genes—five so far—that are involved in vernalization in the model plant Arabidopsis thaliana, although none is related to the wheat VRN genes. Amasino describes the Dubcovsky team's work as “outstanding. It's not trivial to do what they did in wheat. We have it easy in Arabidopsis.

    Researchers looking for Arabidopsis genes have an easier time partly because the genome of their favorite plant was completely sequenced 4 years ago. That hasn't been done yet for wheat, which has an unwieldy genome. Earlier genetic studies by Dubcovsky's team and others had shown that two genes—called VRN1 and VRN2—control vernalization in wheat, barley, and other cereals.

    About a year ago, Dubcovsky bagged VRN1, first mapping its location in the wheat genome and then scanning that region for likely candidate genes. The most promising candidate was a gene related to AP1, which is required for the transition from vegetative growth to flowering in Arabidopsis, Dubcovsky's team reported in the 13 May 2003 issue of the Proceedings of the National Academy of Sciences. The gene's putative link to vernalization was buttressed by the finding that prolonged cold exposure turns up its activity in winter wheat, which requires vernalization, but not in spring wheat, which can flower without a long cold exposure.

    Now the Dubcovsky team has cloned VRN2, which has an activity pattern opposite to that of VRN1—going down, not up, during cold exposure. Mutations that inactivate it produce spring wheat lines—evidence that the team has found the right gene. Furthermore, introducing an RNA that inhibits VRN2 activity into a line of winter wheat accelerated flowering, as expected for a gene that suppresses flowering.

    Faster blooms.

    Introducing an RNA that inhibits the activity of VRN2 speeds up flowering (right) compared to an unmodified wheat plant (left).

    CREDIT: L. YAN AND J. DUBCOVSKY

    The model emerging from this work and previous genetic studies suggests that the activities of VRN1 and VRN2 are connected: Prolonged cold reduces VRN2 activity, leading to up-regulation of VRN1 and flowering. “We know that these genes talk with each other somehow,” Dubcovsky says. Now, the challenge is to learn how they communicate and to find the pathway by which cold turns down VRN2 expression.

    Arabidopsis, like wheat, has both rapid-flowering summer varieties and varieties that require vernalization to flower. Researchers are a bit further along in identifying the genes involved in vernalization in this species. Two of the key genes go by the names FRIGIDA (FRI) and FLOWERING LOCUS C (FLC).

    About 5 years ago, Amasino's group and one led by Elizabeth Dennis and James Peacock of the Commonwealth Scientific and Industrial Research Organisation's plant industry division in Canberra, Australia, cloned FLC, which, like VRN2, codes for a repressor of flowering. Subsequent work showed that when FRI is present, FLC activity is elevated, but that prolonged exposure to cold turns down FLC's activity, thus allowing the plants to flower rapidly when conditions are right. Or as Amasino puts it, “FRIGIDA and the vernalization pathway are fighting over who gets to control FLC.

    Once vernalization turns down FLC activity in Arabidopsis plants, it stays down—an indication that the gene has undergone some kind of epigenetic change that keeps it repressed. Recent work indicates how that happens. In the mid-1990s, Dean and her colleagues identified two genes, called VRN1 and VRN2, that are needed to maintain vernalization in Arabidopsis. (Although they bear the same names, the wheat and Arabidopsis VRN genes are not related.) The structure of VRN2 suggested that it might be involved in adding methyl groups to the histone proteins associated with the DNA in chromosomes—a change known to lead to gene silencing in other species. Results reported in the 8 January issue of Nature by the Dean and Amasino groups confirmed this idea.

    In addition, Amasino and his colleagues identified a gene they call vernalization insensitive (Vin3) because mutations in the gene completely block the vernalization response. Their results suggest that the Vin3 protein acts early, removing certain acetyl groups from histones and thus paving the way for later methylation by the VRN proteins.

    As with wheat, Arabidopsis studies have not yet revealed how plants sense prolonged cold and transmit that information to the vernalization genes. So far, the genes found in the two species have been different, but the possibility remains that the sensing pathways are related. Because researchers can now screen for new mutant genes that affect the activity of the genes already in hand, they should be able to develop a complete picture of the biochemical underpinnings of vernalization.

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