News this Week

Science  12 Mar 2010:
Vol. 327, Issue 5971, pp. 1308
  1. Latin America

    Chile's Earthquake May Set Back Research for Years

    1. Jocelyn Kaiser and
    2. Antonio Regalado

    Scientists in Chile have lost years of research from last month's massive earthquake, which overturned microscopes, destroyed research labs, and took the life of a young marine biologist. Researchers in fields from developmental biology to oceanography are trying to regroup.

    The worst structural damage was to the two research universities in Concepción and Talca, both close to the epicenter of the magnitude-8.8 quake that struck on 27 February. At the University of Concepción, a fire ravaged the building that houses one of Chile's leading chemistry centers, including an advanced polymers lab. The building, although “still standing, burned completely,” says Jaime Baeza, the university's vice-rector for research.

    Because of aftershocks and structural damage, faculty members returned to the university only this week to rescue what might be left of research projects, Baeza says. Given losses of equipment and lab space, Baeza says, “the quake may have set us back 3 or 4 years, even 10 years.” The university plans to reopen in April.

    At the University of Talca 260 kilometers north of Concepción, damage to a modern agricultural biotechnology center and other buildings has surpassed $10 million, officials say. Bioinformatics researcher Danilo González says that high-performance computers were also destroyed and, as a result, several undergraduate and Ph.D. students' theses may be lost.

    Some Chilean scientists worry about the long-term impact of the quake. The scientific community in Chile “has grown exponentially in the last 20 years,” but it's still small and vulnerable, says Roberto Mayor, a Chilean developmental biologist at University College London. “The effect will be amplified,” predicts Mayor, who is trying to raise funds to help. María Elena Boisier Pons, president of CONICYT, Chile's science funding agency, says, “We'll need as a country to reconstruct our labs and our science.”


    The massive earthquake that struck Chile last month battered the biotechnology building at the University of Talca (top). The quake also left a biology lab at the University of Chile in Santiago in disarray.


    A tsunami that followed the quake also wreaked havoc, killing a researcher involved in an ecology expedition to Robinson Crusoe Island off Chile's coast. Ecologist Álvaro Palma of Pontifical Catholic University of Chile in Santiago, who had dispatched the team of five to the island, says the group scrambled uphill from their house near shore to escape the wall of water. But Paula Ayerdi, a 28-year-old research assistant in marine biology, became separated. Her body was found along the shore the next day.

    The wave also gutted a marine research station operated by the University of Concepción in Dichato, a fishing town about 50 kilometers from the city, and left its research vessel, the Kay-Kay, stranded half a mile from shore, according to Carola Espinoza, a marine biologist at the university.

    “Our laboratory was totally destroyed by the tsunami. It's turned upside down and full of sediment and algae,” Espinoza says. Washed away were marine samples dating from the 1960s, aquariums used in breeding experiments, the station's library, and microscopes and other valuable equipment.

    The university's oceanography program at Dichato and on the main campus in Concepción is “very strong” and attracted many collaborators from the United States and Europe to study a region of upwelling and high productivity off the Chilean coast, says Daniel Repeta, a marine chemist at Woods Hole Oceanographic Institution in Massachusetts. “I'm sure it's a big setback,” says Repeta, who visited Dichato several years ago.

    Farther north at the University of Chile in Santiago, the earthquake severely shook the modern four-story Millennium building that houses biology labs, toppling glassware, microscopes, incubators, PCR machines, and refrigerators. A flood from a broken water pipe on the top floor and an electricity shutoff added to the damage, says Miguel Allende, who heads a cell genomics center in the building.

    Researchers rushed to their labs the morning after the quake to slosh through chemical-laced water and salvage cell cultures and other frozen samples and reagents. But many materials were lost, Allende says.

    About half of the biology department's 40 or so research groups suffered losses from the quake, says department chair Ana Preller. “The big problem is equipment,” Preller says. Her preliminary estimate is $600,000 in losses. The quake also shifted and may have damaged a cyclotron in the physics department.

    Allende and other faculty members have sent some students to colleagues' labs for now. Colleagues abroad have also offered to take in students from Concepción and Santiago. “It's taken 11 years to get where I am now. Doing science here is very hard. It's discouraging. But maybe it will be an opportunity to do some new things,” Allende says.

  2. Pharmacology

    The Puzzling Rise and Fall of a Dark-Horse Alzheimer's Drug

    1. Greg Miller

    The announcement last week that a closely watched phase III clinical trial for Alzheimer's disease had failed to show a significant effect deals yet another demoralizing blow to patients, families, and caregivers. It may also mark the beginning of the end to one of the most unusual stories in Alzheimer's drug development.

    The trial involved a drug called Dimebon, which catapulted into the limelight with a spectacularly successful trial published in The Lancet in 2008. “It looked better than anything we'd ever seen before,” says Samuel Gandy, an Alzheimer's researcher at Mount Sinai School of Medicine in New York City.

    Dimebon was an unlikely Alzheimer's drug. An antihistamine introduced in Russia in 1983, it turned up in a screen for potential Alzheimer's drugs led by scientists at the Institute of Physiologically Active Compounds in Chernogolovka, Russia. In follow-up experiments, the drug improved the performance of memory-impaired rats, and a pilot study with 14 Russian Alzheimer's patients showed encouraging results, published in a 2001 paper in the Annals of the New York Academy of Sciences.

    Based on those findings, one of the Russian scientists, Sergey Bachurin, came to the United States to seek investors and partners in developing the drug. Bachurin persuaded San Francisco–based biotech entrepreneur David Hung to establish a company, called Medivation, and reportedly exchanged the rights to the drug for equity in the company. With initial support from private investors, Medivation recruited several top experts to design a larger clinical trial. The experts included Paul Aisen, a neurologist at the University of California, San Diego, who oversees government-sponsored clinical trials as director of the Alzheimer's Disease Cooperative Study; Rachelle Doody of Baylor College of Medicine in Houston, Texas; and Mary Sano of Mount Sinai.

    The results were remarkable: The 2008 Lancet study, a double-blind, placebo-controlled trial, reported that 89 people with mild to moderate Alzheimer's disease who took Dimebon showed significant improvements in memory and cognition, as well as the ability to carry out the activities of daily life. The effects far surpassed those of any Alzheimer's drug on the market or in development, and Hung says several pharmaceutical companies bid to purchase the rights to Dimebon. Pfizer won, paying $225 million.

    Bad news.

    A recent trial dims hopes that Dimebon will be an effective treatment for Alzheimer's disease, which loads the brain with amyloid plaques (right).


    The Lancet findings struck many researchers as too good to be true, says Rudolph Tanzi, an Alzheimer's researcher at Harvard University. “Nobody could figure out what an antihistamine does” to fight Alzheimer's disease, says Sam Sisodia of the University of Chicago in Illinois. Several ideas have been floated, Sisodia says, but supporting evidence is scant. Still, he and others say they were willing to suspend their disbelief, largely because of the involvement of Aisen, Doody, and Sano. “If you had to pick the five best trialists in the world, they would be three of them,” Gandy says.

    But the new trial, despite a design almost identical to that of the Lancet study, yielded dramatically different results. It enrolled 598 patients with mild to moderate Alzheimer's. This time, however, there were no significant differences between the Dimebon and placebo groups. “It's hugely disappointing,” says Aisen. He says he's at a loss to explain the discrepancy, although he notes that it's not unheard of for a drug to have both positive and negative trials before winning approval. Gandy, however, says, “I'm not sure that there has ever been such a night-and-day difference in replicate trials that turned out to be biological variation.” Medivation and Pfizer are poring over the data in search of an explanation, says Hung, who declined to discuss their leading hypotheses. For now, the companies will continue with three other Dimebon trials already under way for Alzheimer's disease, in addition to one for Huntington's disease.

    But to some, Dimebon is starting to look like a dark horse whose race is run. “I don't think that the drug is dead and buried today, but we need to get some clarity or good news soon,” Gandy says.

  3. Ecology

    Severe Drought Puts Spotlight on Chinese Dams

    1. Richard Stone

    XISHUANGBANNA, CHINA—Smoky haze hangs over the hills in this subtropical corner of China bordering Laos and Myanmar. The smoke is familiar: During the dry season, farmers across Yunnan Province burn fallen leaves, banana fronds, and more to make ash-based fertilizer. More unusual here, and more troubling, are the sickly yellow bamboo stands and the exposed bed of the Lancang River. “It's the worst drought in that region since 1949,” the founding of the People's Republic of China, says Lu Juan, vice director of the Institute of Water Resources and Hydropower Research in Beijing.

    Southwest China's monsoon-driven climate doesn't bring much precipitation in autumn and winter. But this year's dry season—coupled with a late start and early end to last year's rainy season—has left the region parched. Yunnan officials estimate that some 6 million people are short of drinking water and that the dry spell has ravaged winter wheat and other crops, inflicting $1.5 billion in losses.

    The drought's effects have spilled across China's borders, stoking tensions with neighbors and prompting scientific debate. Rice yields in Thailand are expected to take a big hit, and the Mekong River—the name for the Lancang south of China—is in many stretches less than a meter deep, its lowest level in decades, making it impassable to tour boats and cargo ships. Researchers worry about how the low water level may affect fisheries and critically endangered species such as the Mekong giant catfish, which in the coming weeks would normally spawn in the upper Mekong.

    Environmental groups in Thailand and elsewhere lay at least part of the blame on China's doorstep. They claim that China's management of a series of dams on the Lancang has aggravated the unfolding crisis. The Thai media has helped stir up emotions; one editorial in the Bangkok Post last month was headlined “China's dams killing Mekong.” Yet Chinese engineers and some other scientists say the criticism is unfounded.

    Rising tensions in Asia could usher in a protracted regional conflict over resources, especially as many key rivers cross several borders. In Asia, “competition for transboundary water utilization will be fierce,” says He Daming, director of the Asian International River Centre of Yunnan University in Kunming. China will be at the center of many squabbles. With some 110 rivers and lakes straddling its borders with 19 countries, says He, “China is the most important upstream riparian country in Asia, even in the world.”

    A major feature in this vast waterworks is the 800,000-square-kilometer Lancang-Mekong basin, home to some 60 million people. From glacier-fed headwaters on the Qinghai-Tibetan plateau, the Lancang wends 2160 kilometers through southwestern China before entering the Golden Triangle region of Burma, Laos, and Thailand. The river finally spills into the South China Sea off Cambodia. In the late 1980s, China began work on eight cascades, or hydroelectric dams, on the Lancang's lower reaches, aiming to supply 15.6 gigawatts a year. Four have been completed, including Xiaowan, the tallest at 292 meters.


    Fan Ze-xin examines seedlings in southern Yunnan; a prolonged drought is draining the lifeblood from forest life and (above) the upper Mekong.


    Some environmental groups contend that the Mekong flow regime has been altered by dredging and dam construction, suppressing fish catches. Living River Siam, a nonprofit based in Chiang Mai, Thailand, has called on governments to “immediately stop all works on hydropower and river development on the Lancang-Mekong.”

    Yet the dams on the lower Lancang reduce runoff only during the rainy season, when reservoirs are filling, according to Chen Guanfu of Hydrochina Corp. Dry season water releases should increase river volume by 35%. “There are a lot of accusations that the dams in China are exacerbating the current low water levels, but the Chinese have informed [downstream nations] that they will not fill any reservoir during the dry season,” says Roger Mollot, a fisheries expert with the World Wide Fund for Nature in Vientiane, Laos. The dams would also help rein in flooding, says Zhou Shichun of the General Institute of Hydropower and Water Resource Planning and Design in Beijing.

    The biggest ecological impact could be less sediment swept downstream as silt accumulates in the reservoirs. But that would be a good thing, Zhou insists: It would “facilitate irrigation and navigation” on the Mekong. Others, however, point out that decreased sediment loads will likely lead to erosion of downstream riverbanks and the Mekong Delta.

    Hydropower authorities have taken ecological effects into consideration, Zhou says. Work on one dam—the Mengsong Cascade, which would be sited nearest the border—has been postponed indefinitely, he says, to protect four species of migratory fish, including the giant pangasius (Pangasius sanitwongsei), whose conservation status is uncertain (Science, 22 June 2007, p. 1684). The freshwater goliath has not been reported above the Mengsong dam site, so the other dams would not affect it, Zhou says.

    The first victim of an ecological crisis could be the Mekong giant catfish, which has been on the ropes for years. “It is not clear if the current drought conditions will impact successful spawning of the wild population of giant catfish, but low water levels may make them more vulnerable to fishing pressure,” says Mollot.

    Things may get worse due to climate change. After examining weather and tree ring data, Fan Ze-xin, a tree physiologist at Xishuangbanna Tropical Botanical Garden, has found that in the past 40 years Yunnan has grown warmer and drier—a trend that started long before the dams were built. In a nature reserve near the botanical garden, he grabs leaves from a seedling; dry as parchment, they disintegrate. “Some of these leaves are fresh,” Fan says. “I haven't seen it as bad as this.”


    From Science's Online Daily News Site

    And the Winners of Our Blogging Contest Are … Last month, Science reporters traveled to San Diego, California, to cover the annual meeting of the American Association for the Advancement of Science (which publishes ScienceNOW). To help us out, we recruited meeting attendees to share their insights and experiences on our guest blog, ScienceBloggers. We were impressed with many of the entries, but in the end we could only choose three winners.

    New HIV Hiding Spot Revealed Powerful anti-HIV drugs have come tantalizingly close to eradicating the virus from people, driving the blood level of HIV so low that standard tests cannot detect it. But no one has been cured: The virus comes roaring back in everyone who stops taking the drugs. A new study has identified one of HIV's main hideaways, raising intriguing possibilities about how to remove it.

    Pain's in the Genes The difference between a child who laughs off skinned knees and one who cries at the smallest pinch could be in their DNA. Subtle changes to a certain gene seem to determine how sensitive people are to pain, according to new research.


    Solving the Rangeland Paradox There's a saying in Texas: We don't have a water problem, we have a brush problem. The idea is that when shrubs and trees invade former grazing lands, they soak up so much groundwater that streams slow down and water supplies to cities and towns decrease. But a new study suggests that the opposite is true: Trees and shrubs on the prairies may actually help recharge the groundwater. The findings should force a rethink of land-management techniques for much of the United States's former rangelands.

    Read the full postings, comments, and more on

  5. North Korea

    New Tuberculosis Lab Hailed as Breakthrough in Health Diplomacy

    1. Richard Stone
    Team spirit.

    Sharing the grunt work, TB project members roll a water tank into position.


    Last fall, Sharon Perry pulled her first shift on a North Korean labor brigade. The Stanford University epidemiologist spent 10 days in November in Pyongyang, working side by side with Ministry of Public Health colleagues—from student nurses on up to senior physicians—to help set up the isolated nation's first laboratory capable of growing the mycobacterium that causes tuberculosis (TB) and detecting drug-resistant strains. The weather was unseasonably cold, so for 12 hours a day the unlikely comrades toiled in their parkas on tasks that included smashing old floor tiles with sledgehammers, testing microscopes, and installing ultramodern cabinets in which pathogens can be handled. “We all pitched in,” says Perry, director of the Stanford-led Bay Area TB Consortium.

    Perry and her colleagues have defied the odds in getting the project off the ground. U.S. scientists have long had fitful relations with counterparts in North Korea: No matter how noble the intentions, science cooperation efforts have, with few exceptions, ended up stillborn or abandoned. In recent months, some U.S. nonprofits engaged with North Korea “have found their counterparts to be reeling from the effects of intensive reeducation, dispersed overseas or to the provinces, or moved behind intermediaries,” says one seasoned observer. Yet the budding TB lab has proceeded at a fevered clip. “We've kept our heads down and stayed out of politics,” explains Heidi Linton, executive director of Christian Friends of Korea (CFK) in Black Mountain, North Carolina, a humanitarian organization and project partner along with the Bay Area TB Consortium and the Nuclear Threat Initiative (NTI). A team plans to return to Pyongyang next month to get the lab up and running.

    That can't happen a moment too soon. Following years of economic decline and the severe famines of the mid-1990s, TB and other infectious diseases have surged in North Korea. Due to increased surveillance and an expanding epidemic, Perry says, between 2006 and 2008 the number of TB cases doubled to 344 per 100,000 people. “That's similar to rates seen in sub-Saharan Africa,” says Gary Schoolnik, an infectious disease researcher and physician at Stanford University School of Medicine in California.

    Until now, North Korean clinicians have relied on the age-old diagnostic technique of staining sputum for acid-fast bacilli, which catches about half of TB cases. But this approach can't reveal whether patients are infected with drug-resistant strains. “The prevalence of drug resistance could be very high,” says Schoolnik.

    A looming drug shortage threatens to make matters far worse. More than 90% of North Korea's TB drug stocks have been supplied by the Global Drug Facility, a nonprofit housed at the World Health Organization (WHO), under a grant that will run out this year. An agreement with the Global Fund to Fight AIDS, Tuberculosis and Malaria would continue supplying the drugs, but the earliest that could happen, sources say, is next year—leaving a minimum 6-month gap in coverage. “It's a nightmare scenario,” says Linton. “You can't just leave TB patients without medicine.” Based on discussions with WHO officials, Perry estimates that at least $1 million must be raised by July to purchase drugs. She and others are courting potential donors.

    An unchecked TB epidemic would pose “a direct threat to China and other neighbors,” says epidemiologist Louise Gresham, director of NTI's Global Health Security and Epidemiology initiative. NTI, a nonprofit in Washington, D.C., hopes the project might strengthen ties between two countries that are still technically at war. Experts not affiliated with the effort agree. “Collaboration and data sharing between North Korean and U.S. experts in the area of health security can, one hopes, help build the trust so necessary to resolving other urgent security issues,” says Stuart Thorson, a political scientist at Syracuse University's Maxwell School in New York state who leads a U.S.–North Korea informatics exchange.

    It was a veteran North Korea analyst, Stanford political scientist John Lewis, who got the ball rolling on the TB lab. In 2007, when North Korea–U.S. relations were particularly fraught, Lewis cast around for ideas for an overture that could ease tensions. Lewis consulted David Heymann, then the director of communicable diseases at WHO, who highlighted the unfolding TB emergency. Lewis next contacted Stanford's resident TB experts, Perry and Schoolnik.

    To lay the groundwork, the Bay Area TB Consortium hosted a five-person delegation from the North Korean health ministry in January 2008. “We identified their most pressing needs,” says Schoolnik. These were the TB lab and an uninterrupted supply of drugs. Perry, who Schoolnik calls “the driving force” of the project, rang up Gail Cassell, a vice-president at the pharmaceutical giant Eli Lilly who has worked on TB in the former Soviet Union. Cassell approached NTI, which in short order invited Stanford to submit a proposal. NTI awarded them $230,000 to purchase a WHO-recommended inventory of lab equipment—biosafety cabinets, incubators, centrifuges, freezers, and culture plates—and power conditioners, generators, and other devices to cope with an unreliable power grid. “The stuff is state-of-the-art,” says Schoolnik. “It made us envious.”

    Getting the goods to Pyongyang was the next challenge. In stepped CFK, which for 15 years has been providing humanitarian assistance to North Korea. “For years, we'd been hearing from North Korean doctors and health officials about the need for a TB lab,” says Linton. In mid-2008, she got wind of the nascent Stanford effort and called Perry. “We had expertise they needed,” Linton says. For starters, CFK had experience rehabilitating hospitals in North Korea and knew how to navigate the procedures for obtaining export licenses from the U.S. Department of Commerce.

    CFK has proved to be the project's linchpin. The North Koreans trusted it. “We experienced extraordinary cooperation,” says Perry. By December 2008, the Koreans were on board for the TB lab. The following May, CFK, which has also spent about $230,000 on the project, arranged for Perry, Linton, and others to visit the health ministry's National Tuberculosis Institute in Pyongyang to hash out a plan. As with past projects, says Linton, “we realized we would have to bring every nut, bolt, and light bulb.”

    Trial run.

    California-based microbiologist Grace Lin puts the new lab through its paces.


    The lab equipment arrived in Pyongyang on a rainy day last October. “When we opened the containers, the Korean researchers' eyes lit up,” Linton says. “You could feel the energy—they realized this was finally going to happen.” A CFK team will return next month to complete the wiring and plumbing and check on other renovations that the North Koreans were due to complete. The Stanford team hopes to hold training workshops when the lab is operational, and NTI intends to make periodic visits to verify that the equipment is being used as agreed.

    Down the road, the U.S. side hopes that the bonds formed in bringing the lab into being will blossom into a full-fledged collaboration. “As trust grows, we may be able to build on this relationship and start scientist-to-scientist and lab-to-lab cooperation,” says Gresham. In the annals of U.S.–North Korea relations, they are already off to a remarkable start.

  6. ScienceInsider

    From the Science Policy Blog

    The H1N1 virus may have had less impact this winter than expected, but a new report from Hong Kong suggests that the virus in pigs has picked up genes from the human version.

    China will increase its science and technology budget by 8%, to $24 billion, in 2010. “We need to emancipate our minds and boldly make breakthroughs and innovations,” Premier Wen Jiabao told the legislators meeting at the National People's Congress.

    Meanwhile, Canada's pending budget is light on new funds for science. Finance Minister James Flaherty moved to partially offset scheduled cuts in funding for the nation's three granting science councils, though they'll still take a blow, and there will be tighter competition for research operating grants.

    A new study of 30 unnamed federal workers found no difference in their experiences regarding research integrity in the Obama and Bush Administrations. The George Washington University study looked at accessing data, reviewing potential research, clearing papers for publication, and communicating with the public.

    The National Research Council has recommended that U.S. funding agencies support an interdisciplinary research program on how past climate influenced human evolution. It would include drilling ancient lakebeds, studying new fossil sites, modeling paleoclimate, and educating the public.

    A panel has recommended that the European Southern Observatory (ESO) build the record-setting European Extremely Large Telescope at Cerro Armazones in northern Chile. But Spain may continue its fight for a site on its La Palma island. None of ESO's current scopes in Chile was harmed in the recent earthquake.

    For the full postings and more, go to

  7. Psychiatry

    APA Seeks to Overhaul Personality Disorder Diagnoses

    1. Constance Holden

    Personality disorders are hard to pin down. They don't have a common defining mood or behavior, people don't get hospitalized for having one, and a drug won't cure one. But they can cause all kinds of havoc. People with antisocial personalities, regularly encountered in crime news, are well-known. But other types of these disorders feed into high rates of alcoholism, drug addiction, suicide, and the dysfunction found in many offices, families, or soap operas.

    A personality disorder “at the core” involves “failure to develop healthy functioning in self and interpersonal domains,” according to psychologist Lee Anna Clark of the University of Iowa in Iowa City, a member of the American Psychiatric Association's (APA's) work group that is proposing revisions for personality disorders in the forthcoming fifth version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), often referred to as psychiatry's bible (Science, 12 February, p. 770). These disorders are in for a “major overhaul,” says APA psychiatrist Darrell Regier, co-chair of the broader effort. The goal is to create a more flexible and precise system, but some critics say the changes are too complicated for the busy clinician.

    The current edition, DSM-IV, identifies 10 personality disorders, with a list of criteria for each. But these have been criticized for having arbitrary diagnostic thresholds and for clumping together people with quite different symptoms. Work group chair Andrew Skodol, a psychologist at the University of New Mexico, Albuquerque, says, for example, that with nine criteria (five required for a diagnosis), there are 256 ways that a person can be diagnosed with “borderline” personality disorder. Furthermore, “more than half of people diagnosed with one personality disorder are diagnosed with a second or third or even fourth,” says Clark. And despite all the choices, many end up in the “not otherwise specified” (NOS) category. The work group is proposing a system members feel will better capture the range of pathology.

    Take borderline personality disorder. “Borderline” used to be a way of referring to a state somewhere between neurotic and psychotic. But since the 1970s, it has become one of the more extensively researched personality types—often found in young women who tend to be self-centered, hysterical, emotionally dependent, and often suicidal. Marilyn Monroe is often cited as an example; another is Glenn Close's character in Fatal Attraction.

    Slimmed down.

    Proposed changes would reduce the number of personality “types.”

    Under DSM-IV, a clinician would make a diagnosis of borderline personality disorder if a patient displayed at least five from a list of nine symptoms such as impulsiveness, self-mutilating behavior, and “chronic feelings of emptiness.” Under the new regime, the clinician would first determine whether the person's functioning is so impaired that she qualifies for a general diagnosis of personality disorder. The heart of the assessment would be a “trait profile” compiled from a list of six major domains of personality covering areas such as “introversion,” “antagonism,” and “schizotypy” (odd or eccentric behavior).

    The clinician could also refer to five suggested “types” of personality disorders—including “borderline type”—pared down from the current 10 (see box). The four others would be antisocial/psychopathic, avoidant (anxious and fearful of rejection), obsessive-compulsive, and schizotypal. The latter two contain elements of more serious diagnoses in the categories of anxiety and psychosis but do not meet all the criteria.

    One venerable type did not make the cut: narcissistic personality disorder. That's controversial, says psychologist Drew Westen of Emory University in Atlanta. The diagnosis is “widely used—and nobody has suggested it doesn't exist.” Skodol says narcissism is a trait seen in more than one type of disorder and is covered under the domain of “antagonism.”

    On the edge.

    Alex Forrest, played by Glenn Close in Fatal Attraction, fits the diagnosis of a borderline personality.


    Clark and Skodol say that in practice, many people with personality disorders will fall outside those five types. But they'll get better diagnoses because, instead of being designated “NOS,” they will be profiled based on the six traits.

    Some experts question how useful the new system will be. Westen lauds the group for trying to make diagnosis “more sophisticated clinically.” But, he says, by trying to combine the list of five personality types with six crosscutting traits, “what they've come up with is a camel—a horse made by committee.”

    Psychologist Thomas Widiger of the University of Kentucky in Lexington thinks the proposed overhaul is “terrible,” leaves too much to the clinician's subjective judgment, and will create new headaches for insurance companies. It is “so complicated, it will not be used,” he says. “Clinicians will match to one of those five [types]. Then they'll be done.” Skodol is more optimistic, saying that clinicians can choose how deeply detailed their diagnosis is based on “available time, information, and expertise.”

    Skodol's group also wants to put personality disorders on the same footing as other mental disorders. DSM lists disorders in two different categories, or “axes.” Most are on Axis I; personality disorders are on Axis II (along with intellectual disabilities) because they are seen as stable, chronic conditions rather than episodic illnesses. Moving them to Axis I, says Clark, “makes the statement that personality disorder is just as critical to assess as any other diagnosis.”

  8. Newsmaker Interview

    A Civil Conversation About Animals in Research

    1. Greg Miller

    In 2006, neuroscientist Dario Ringach of the University of California, Los Angeles (UCLA), sent an e-mail to several animal-rights groups announcing that he would give up his primate research if they would leave him and his family alone. After years of threats and harassment, including masked protesters banging on his windows at night, Ringach shifted his research on the visual system to studies with human volunteers and theoretical work.

    After keeping a low profile for a few years, Ringach has recently begun speaking out about the benefits of animal research and against a spate of attacks on researchers at UCLA and elsewhere (Science, 21 December 2007, p. 1856; 8 August 2008, p. 755). Along with UCLA neuroscientist David Jentsch, whose car was torched by animal-rights activists in March 2009, Ringach co-founded a pro-research group called UCLA Pro-Test (Science, 1 May 2009, p. 574). In February, Pro-Test teamed up with Bruins for Animals, an animal-rights group on campus, to organize a panel discussion among experts with differing views on animal research that was open to UCLA students and staff. Last week, Ringach spoke with Science about the event and the renewed attention he's gotten from animal-rights extremists. For a video of the UCLA event and links to related blog coverage, see

    Q:What made you decide to start speaking publicly in favor of animal research?

    D.R.:After my decision [in 2006], I was left alone [by activists] for a while, but it was hard to watch my colleagues here at UCLA still being targeted with such violence and hate. I was really inspired by David Jentsch. After his car was blown up, he walked into my office and asked if I thought a good response would be to hold a pro-research rally on campus. I decided to join him. It was almost an immediate reaction.


    Q:What did you hope to accomplish with the recent panel discussion?

    D.R.:We never discussed in detail what the goal was. On the personal side, it was really modest. I wanted to show that we could hold a civilized discussion on this topic.

    Q:Who was on the panel?

    D.R.:We had six speakers. It was me, Colin Blakemore [a neuroscientist at the University of Oxford in the United Kingdom], Janet Stemwedel [a philosopher at San Jose State University in California] on the side in favor of animal research. And on the other side was Ray Greek [president of Americans for Medical Advancement, a group that opposes animal research], Niall Shanks [a professor of history and philosophy of science at Wichita State University in Kansas], and Robert Jones [a philosopher at California State University, Chico].

    Our goal was to bring to the panel individuals with a range of positions. One of the misperceptions is that people segregate into these binary positions, that we either support all types of animal research or we condemn everything, and it's not true. People hold a continuum of views on this issue.

    Q:What was the tone of the discussion?

    D.R.:The tone was civil. Everyone got to speak their mind. At the end of it all, I had more animal-rights activists coming up to thank me for my participation than my own colleagues, which was kind of refreshing.

    Q:Did this accomplish anything?

    D.R.:I think we got to know each other a little better. I understand their concerns about animals. And I think they understand that scientists are not the monsters some people are trying to convince the public we are. Our work is not driven by the pleasure of harming an animal, nor by greed, but by our honest belief that we're trying to advance medical knowledge and medicine.

    Q:Restricting entrance to current UCLA students and staff may have kept out some of the more extreme activists. How have they reacted?

    D.R.:To begin with, we started to get these protests at our homes in the weeks leading up to this event. They were trying to prevent this from happening. Then, after the event, one of these groups decided to justify the targeting of my children by [saying activists should begin] protesting at their school. I'm not even doing any animal research at the moment, I've been targeted just for speaking my mind.

    Q:Has there been a counter-response?

    D.R.:After they made these threats public, some of the science bloggers expressed outrage to this notion that my children were fair game. And that's when Bruins for Animals joined us in a joint statement denouncing the harassment and intimidation tactics. We're hoping other animal-rights groups will join us. It would be a tremendous step forward. Most of the time when asked, many animal-rights activists will reply that they're not really for violence, but they understand the frustration of some activists. At least the local organizations we're trying to engage have been very positive in saying that we should give dialogue a chance.

    Q:Do you really think this type of event can end the threats and intimidation?

    D.R.:There is a small group of individuals who are set on using threats and intimidation to convince others of their views, and I don't think there's anything we can do about that. But I think they will become increasingly marginalized, both by the public and by their colleagues in the animal-rights movement. I am hopeful that more open dialogue will force them to decide exactly what they want to do, whether they want to continue with their threats or join us at the table.

  9. Scientific Publishing

    Elsevier to Editor: Change Controversial Journal or Resign

    1. Martin Enserink

    The editor of the journal Medical Hypotheses—an oddity in the world of scientific publishing because it does not practice peer review—will apparently lose his job over the publication last summer of a paper that says HIV does not cause AIDS. Publishing powerhouse Elsevier this week told Editor-in-Chief Bruce Charlton that it won't renew his contract, which expires at the end of 2010, and it asked that Charlton resign immediately or implement a series of changes in his editorial policy, including putting a system of peer review in place. Charlton, who teaches evolutionary psychology at Newcastle University in the United Kingdom, says he will do neither, and some on the editorial advisory board say they may resign in protest if he is fired.


    Editor-in-Chief Bruce Charlton refuses to introduce peer review.


    Elsevier's move is the latest in an 8-month battle over the journal; it comes after a panel convened by Elsevier recommended drastic changes to the journal's course, and five scientists reviewed the controversial paper and unanimously panned it.

    Medical Hypotheses, which says it “will consider radical, speculative and non-mainstream scientific ideas” is the only Elsevier journal not to practice peer review. Scientist, entrepreneur, and author David Horrobin, who founded the journal in 1975, believed reviewers tend to dislike what lies outside the scientific mainstream. Charlton, who succeeded Horrobin in 2003, decides what gets published on his own—although he occasionally will consult another scientist—and manuscripts are edited only very lightly.

    It's a policy that leads to occasional wild and wacky papers—a 2009 article for which the author studied his own navel lint became an instant classic—but the journal is also a “unique and excellent” venue for airing new ideas, says neuroscientist Vilayanur Ramachandran of the University of California (UC), San Diego, who published in the journal 15 times himself and sits on its editorial advisory board. “There are ideas that may seem implausible but which are very important if true,” Ramachandran says. “This is the only place you can get them published.”

    But the journal got in hot water in July after Charlton accepted a paper, previously rejected by the Journal of Acquired Immune Deficiency Syndromes, in which molecular virologist Peter Duesberg of UC Berkeley and colleagues assert that HIV does not cause AIDS and that medical statistics and demographical data do not support the existence of a massive AIDS epidemic in South Africa. Duesberg, a so-called AIDS denialist, has disputed the link between HIV and AIDS since the 1980s.

    Charlton says he is “agnostic” on the question of whether HIV causes AIDS but adds that even papers that are wrong can make interesting points that make the reader think. “If he believes that, he should have a great big health warning on every page saying, ‘This may be rubbish,’” says Nicoli Nattrass, an economist at the University of Cape Town who has studied the effects of AIDS denialism in her country. “This is not just some stupid academic debate. Many people in South Africa still don't believe HIV causes AIDS because there are scientists who say so. And they are dying because of it.”


    Two Medical Hypotheses papers—including one by Peter Duesberg—were retracted after five reviewers unanimously panned them.

    After the paper's publication, prominent HIV scientists John Moore of Weill Cornell Medical College in New York City and Nobelist Françoise Barré-Sinoussi of the Pasteur Institute in Paris wrote Elsevier to ask that the paper be withdrawn. Others asked the National Library of Medicine to delist Medical Hypotheses from the MEDLINE database of biomedical literature, and called on scientists to urge their librarians to cancel the journal. (They also took aim at a second AIDS paper by molecular biologist Marco Ruggiero of the University of Florence, which they say was denialist in nature as well.)

    Following the advice of a private external panel, Elsevier told Charlton on 22 January that Medical Hypotheses would have to become a peer-reviewed journal. Potentially controversial papers should receive careful scrutiny, the publisher said, and some topics—including “hypotheses that could be interpreted as supporting racism”—should be off limits.

    Elsevier also had its flagship medical journal, The Lancet, organize a review of the two papers by five anonymous experts. The reviews, which have been obtained by Science, were unanimously negative; they said that the Duesberg paper was riddled with errors and misinterpretations. “It does not belong in a scientific journal,” one reviewer wrote. On 24 February, Elsevier wrote Duesberg that his paper—which had not yet been printed and which the publisher had pulled from the journal's Web site in August—would be “permanently withdrawn.” Ruggiero received a similar letter.

    Charlton calls the review a “show trial” and says the publisher had no right to override his editorial decision. On his Web site, he has published a selection of more than 150 letters from Medical Hypotheses authors who support him. And on 12 February, 13 of the 19 board members wrote Elsevier to demand that the papers be returned to the journal's Web site and to reject the proposed changes to its editorial policies. Not having peer review “is an integral part of our identity, indeed our very raison d'être,” the group wrote. But board member Antonio Damasio, head of the University of Southern California's Brain and Creativity Institute in Los Angeles, didn't know of the letter and now says that the paper should never have been published. The signatories don't all love the paper either, says board member David Healy of Cardiff University School of Medicine in the United Kingdom. “It's a defense of Bruce, not of the Duesberg paper,” he says.

    Duesberg says Elsevier's measures are an example of “censorship” imposed by the “AIDS establishment.” But Medical Hypotheses' critics applaud the publisher's latest step. “It seems clear that Elsevier has come to realize that there is a problem with Medical Hypotheses and that they are doing what they can to rectify it,” says Moore.

  10. Energy Research

    Matchmaking Is Part of the Party as ARPA-E Marks Its First Birthday

    1. Eli Kintisch

    A little more than a year after the U.S. Congress bestowed $400 million in stimulus funding on an agency that at the time consisted of little more than file cabinets, the Advanced Research Projects Agency–Energy (ARPA-E) is firing on all cylinders. Last week, it marked its first anniversary with a coming-out party. But the 1700 politicians, scientists, industrialists, and investors who attended the 3-day summit in a suburb of Washington, D.C., did more than celebrate a good start. The meeting heralded the agency's fresh approach to doing business, including giving researchers—both funded and rejected by ARPA-E—a chance to interest prospective backers in their scientific wares.

    “The signing of a contract with ARPA-E provides validation to potential investors,” says Riccardo Signorelli of FastCAP SYSTEMS, a Boston-based start-up that received $5.4 million from ARPA-E in December to develop supercapacitors. After the award was announced, ARPA-E program manager David Danielson helped the company find potential business collaborators and sped up the process of securing its next round of funding—$2 million for the 12-person company to pay salaries and market its technology.

    Greener pastures.

    Algaeventure Systems in Marysville, Ohio, received a $6 million award to develop an algae-processing system for biofuel.


    Director Arun Majumdar says that speed is essential for ARPA-E to meet its mission of catalyzing “game changing” energy technologies. And participants say that so far the agency is living up to that promise. Its lean profile—fewer than a dozen program managers, with broad authority to make decisions—has allowed it to move paperwork “like a bullet,” said Ammi Amarnath of the Electric Power Research Institute (EPRI) in Palo Alto, California, which is part of a collaboration that has received $5 million from ARPA-E for smart windows research.

    FastCAP and EPRI were two of 37 winners in ARPA-E's first solicitation, an open $150 million competition that attracted 3700 applicants. A second, more focused call for $100 million issued in December has yielded 500 concept papers, with winners to be announced in the spring. And last week, Majumdar announced a third, $100 million solicitation, for improvements in energy converters and storage and more efficient buildings.

    Notwithstanding the importance of federal support—President Barack Obama has requested $300 million in the 2011 fiscal year so that the agency can sustain its momentum—Majumdar emphasizes that part of ARPA-E's success will be measured in how much private money its grantees are able to attract. So far, so good: Companies have invested an additional $32 million in FastCAP and other first-round winners.

    ARPA-E's sudden arrival on the federal research scene has naturally prompted many questions from the energy community. So Majumdar began the summit with a 1-day, closed-door workshop for attendees to meet face to face with ARPA-E staffers. Later, in public sessions that featured energy rock stars such as investor Vinod Khosla and New York Times columnist Thomas Friedman, officials fleshed out some of ARPA-E's inner workings.

    One facet that has attracted a lot of attention has been its review process. Whereas the first solicitation had required hundreds of volunteers to sift through the deluge of applications, the next rounds will rely more on input from its own program managers, drawing upon their expertise in particular fields. It's a balancing act, says chemical engineer Mark Hartney, who says he took a “fairly significant pay cut” to join ARPA-E after working at the Massachusetts Institute of Technology's Lincoln Laboratory, at DARPA, and in the semiconductor industry. Unlike in basic research, which relies on a proposal's scientific merit, or applied programs, which hinge on meeting strict technical goals, ARPA-E managers look at a mixture of fundamental science, the commercial track record of applicants, and their potential to partner with other scientists. When technical reviewers say “it's possible but very challenging,” says Hartney, “that may be an ARPA-E program.”

    To some, however, that process—whose first step is an eight-page concept paper—can look overly subjective. “Absolutely no reasons are given [for the rejection]. … There is no transparency.” says David Doty of Doty Energy in Columbia, South Carolina, who had proposed research into what are called wind fuels.

    A key goal of the summit was to connect ARPA-E's inaugural grantees—and 64 finalists who didn't get funded—with hundreds of private investors. Chemist Ilan Gur of the Berkeley, California–based SEEO, which fell just short of getting funding last year, said his status as a finalist helped expose him to influential policymakers, investors, and technologists. But physicist Dileep Agnihotri of start-up Graphene Energy in Austin, Texas, said he “hadn't seen much advantage” to being a finalist.

    Although ARPA-E sits outside the Department of Energy's existing research infrastructure, with its director reporting directly to Energy Secretary Steven Chu, DOE officials emphasized at the meeting that their units are well connected to ARPA-E. Top DOE officials spent “hundreds of hours” helping set up the agency last year, said an aide. And ARPA-E has given back, too, says Henry Kelly of DOE's Energy Efficiency and Renewable Energy branch in Washington, D.C. At a recent meeting on power systems, Kelly recounts, ARPA-E's program managers “brought in a guy who built the energy systems for the 787 Dreamliner.”

    But will such collaborations, even in the service of impressive research, impress lawmakers looking to trim federal spending? Majumdar said he was “optimistic” that Congress would support the president's $300 million request for 2011. But in a keynote address, Chu was realistic about the audacity of his effort. “When you start a program and you ask for hundreds of millions of dollars,” he says, lawmakers tend to see it “just like this big piñata.”

  11. On Rarity and Richness

    1. Elizabeth Pennisi

    Two researchers have taken a stab at explaining why oceans have far fewer species than terrestrial habitats.


    If biodiversity were an olympic sport, life on land would take home the gold and the sea might not even enter a team. Given the vastness of the oceans and the length of time life has thrived there, you might expect marine species to outnumber terrestrial ones. Yet, microbes aside, upward of nine in 10 species crowd into the 30% of Earth's surface that's dry.

    It wasn't always that way, say Richard Grosberg and Geerat Vermeij. These researchers from the University of California (UC), Davis, have been studying land and ocean features to understand how evolution proceeds in these two realms. At a recent meeting,* they argued that the difference in diversity is a recent phenomenon.

    Back in the Devonian period, 400 million years ago, the seas were home to an abundance of species, perhaps even more than on land. But about 110 million years ago, land plants went through a burst of speciation; so did the pollinators, fungi, and herbivores associated with them. These relationships made “rare” species possible, as plants acquired help in dispersing their pollen and seeds, resulting in relatively low population densities for individual species. Quickly, their numbers left marine biodiversity behind. The trigger for this terrestrial explosion, Grosberg and Vermeij say, was the evolution of a more efficient way in which land plants use water.

    “This is an excellent and thoughtful paper addressing an issue in biodiversity that has rarely been tackled,” says Michael Benton, a paleontologist at the University of Bristol in the United Kingdom. Jeremy Jackson, a marine ecologist at the Scripps Institution of Oceanography in San Diego, California, calls it “a very big-picture paper. … It's the kind of paper that you think about forever.”

    A physical phenomenon?

    Grosberg started thinking about these issues when he was preparing a series of talks for the 200th anniversary of Charles Darwin's birth. “To me, the interesting question is why are there so many fewer species in the sea than on the land,” says Grosberg.

    The difference is striking. In 1994, Robert May of the University of Oxford in the United Kingdom concluded that 85% of the world's macroscopic species lived on land, based on the existing record of species across the globe. A 2009 study by Benton found landlubbers to be even more common, accounting for 95% to 98% of the world's multicelled species. “Both recognized that the estimates were ballparks, simply because we don't actually know how many species there really are,” says Grosberg.

    The land-sea disparity occurs even in diversity hot spots. A single hectare in a tropical rainforest may contain some 475 tree species and more than 25,000 insect species. But a hectare of coral reef, often called the sea's “rainforest,” might be home to at most 300 coral, 600 fish, and about 200 algal species.

    Grosberg wasn't the first to wonder what lies behind these numbers. In 1990, Richard Strathmann, a marine biologist at the University of Washington, Seattle, wrote an influential paper pointing to physical characteristics of water that could slow down speciation in the seas. Denser and much more viscous than air, water makes travel more challenging. Gases diffuse more slowly. The much higher specific heat of water means aquatic organisms must work harder to stay functional. Organisms can usually detect food, mates, or enemies by sight or smell over longer distances in air than in water. Strathmann; Mark Denny of Hopkins Marine Station of Stanford University in Pacific Grove, California; and Grosberg have all noted that these differences help make terrestrial environments more hospitable and, most likely, more conducive to the evolution of new species.

    Grosberg recognized, however, that physical differences couldn't be the whole explanation. Some polar terrestrial ecosystems are less diverse than nearby marine environments, and freshwater habitats tend to be species-poor compared with similar marine habitats. But he was stumped as to what else might be a factor.

    Then Vermeij heard Grosberg give his talk at UC Davis. “He said to me, ‘You've missed the point,’” says Grosberg.

    Rarity a boon to biodiversity

    A paleontologist, Vermeij tends to see events in a long perspective. “It struck me that this enormous difference can't be very old,” Vermeij recalls.

    Vermeij pointed out that the degree of diversity in the two realms was pretty much equal until about 110 million years ago. About that time, flowering plants took off, as did insects that pollinated them, with species tending to become ever more specialized. Plants came to prefer certain microclimate and soil regimes. Insects pollinated only particular plants; parasites became quite picky about their hosts, and so on. Many kinds of fungi became associated with a favorite host plant. The rise in potential biotic interactions, coupled with more complex habitats than available in the sea, created many more opportunities for new species to form, particularly in the tropics.

    Leaf power.

    Grosberg (left) and Vermeij think the evolution of denser leaf veins (above) helped boost terrestrial biodiversity.


    Along with increased specialization, terrestrial evolution led to dispersed communities. “The medium of air permits … extensive and rapid locomotion,” Vermeij notes. Mobile organisms can locate mates over long distances and easily travel to them. And many stationary plants have gotten animals to do the work of finding mates, transferring pollen, and spreading seeds. The strategy works well: Today, more than 200,000 species are pollinators. In such a system, Vermeij points out, mobile pollinators and dispersers can maintain populations of rare individuals.

    With few exceptions, animal-mediated transfer of gametes, fertilized eggs or larvae, or seeds occurs only on land. Grosberg and Vermeij note that arrying such loads is too challenging under water because of water's viscosity. Instead, marine organisms tend to live in higher-density communities and sometimes employ extraordinary measures for fertilization. Consider barnacles, which have penises that are 10 times the diameter of the barnacle in order to reach a potential mate.

    The development of dispersed communities “is the key to the current extraordinary diversity of species on land,” Grosberg says: High-density populations are at increased risk of being eaten or wiped out by disease, while dispersed communities face reduced competition and predation.

    The missing trigger

    Yet even with this scenario worked out, Grosberg and Vermeij still lacked an explanation for why the gap in diversity between land and sea began to widen when it did. Then, they heard about a February 2009 paper on the evolution of leaf-vein density in flowering plants. C. Kevin Boyce of the University of Chicago in Illinois and his colleagues had measured the densities of leaf veins in many kinds of plants. They also gathered fossil leaf-vein measurements from the published literature. They found that ferns, conifers, and early flowering plants had relatively low leaf-vein densities. But flowering plants that evolved later sometimes squeezed in three to 10 times as many veins per millimeter. Those extra veins correlated with increased photosynthetic capacity, Boyce and his colleagues reported online on 25 February 2009 in the Proceedings of the Royal Society B.

    “That paper was the bridge that Vermeij and I crossed in understanding why the disparity gap happened when it did,” Grosberg recalls. About 110 million years ago, higher leaf-vein densities—and increases in the number of leaves—resulted in greater biomass production. All this added energy set in motion a positive feedback loop that encouraged more specialization. Speciation took off, particularly in the tropics.

    “The idea of key innovations in plant and animal evolution [such as denser leaf veins] is a very old one,” says Michael Hart of Simon Fraser University in Burnaby, Canada, “but connecting it to the land-sea difference in species diversity is important and new.”

    However, the explanation Vermeij and Grosberg propose has some critics. Evolutionary biologist A. Richard Palmer of the University of Alberta in Edmonton, Canada, says so much terrestrial diversity is due to insects and flowering plants that they may overwhelm the real biodiversity picture. And while he calls Grosberg and Vermeij's case for extreme rarity being more feasible on land “a novel contribution,” he points out that some deep-ocean species are also quite rare. “Rarity doesn't seem unique to land,” he says. And Strathmann points out that the difference in the number of species on land versus the number in the sea may be exaggerated because many marine species have gone unrecognized.

    Nevertheless, Grosberg and Vermeij's ideas are attracting attention. “Every step of the way [in their argument] is to some degree conjectural,” says Jackson. “But every step of the way makes sense.”

    • * The Society for Integrative and Comparative Biology meeting was held 3 to 7 January in Seattle, Washington.

  12. Physics

    Ironing Out Consensus on the Iron-Based Superconductors

    1. Adrian Cho

    The emerging understanding of the 2-year-old materials could change physicists' views on the decades-old mystery of high-temperature superconductivity.

    The first superconductors—materials that carry electricity without any resistance—were discovered in 1911. Half a century passed before physicists figured out how metals such as niobium perform that mind-bending feat at a few degrees above absolute zero. In 1986, researchers discovered complex compounds containing copper and oxygen that become superconductors at much higher “critical temperatures”—now as high as 138 kelvin. Twenty-four years later, such “high-temperature superconductivity” remains the biggest puzzle in condensed-matter physics.

    Given those struggles, it's no wonder that Paul Canfield, a physicist at Ames Laboratory in Iowa and Iowa State University, bristles when asked if scientists have deciphered the newest superconducting marvels, iron-based materials that emerged 2 years ago and have critical temperatures as high as 56 kelvin (Science, 25 April 2008, p. 432). “Here we are at 2 years and you're asking, ‘Are we there yet, Daddy?’ Come on!”

    Yet progress on the materials has been phenomenal, say Canfield and others. In February 2008, Hideo Hosono, a materials scientist at the Tokyo Institute of Technology, and colleagues reported that a compound of lanthanum, iron, arsenic, oxygen, and fluorine (LaFeAsO1−xFx) becomes a superconductor at 26 kelvin. Researchers have since discovered four families of iron-based superconductors with distinct crystal structures. Using tools honed on the copper-and-oxygen superconductors, or “cuprates,” they have made measurements that took decades to achieve in the older materials.

    Most important, although physicists cannot say exactly how the iron-based superconductors work, they have developed a scheme that many say captures the essence of what's going on. “There is a kind of general consensus of where the superconductivity is coming from,” says Patrick Lee, a theorist at the Massachusetts Institute of Technology in Cambridge. “We don't have a full solution yet, but the situation is better than in the cuprates.”

    In fact, the emerging portrait of the iron-based superconductors jibes with some theories of the cuprates and seems to undermine more-exotic alternatives. So if physicists are on the right track with the iron-based superconductors, then the cuprates may not be so inscrutable after all.

    Grab your partner!

    For electrons in a metal, moving is usually a drag, as they ricochet off the jiggling ions in the crystalline material and lose energy. In a superconductor, electrons avoid such energy-sapping collisions. In 1957, the American theoretical physicists John Bardeen, Leon Cooper, and John Robert Schrieffer explained how that happens in ordinary superconductors such as niobium chilled to 9.3 kelvin.

    The electrons form pairs, the theorists explained. Deflecting an electron then requires breaking the pair, and at low temperatures there isn't enough energy around to do that. So the pairs glide freely. The negatively charged electrons are glued together by vibrations of the positively charged ions called “phonons,” the theorists showed; the motion of one electron sets off a phonon that attracts another electron.

    The details of this “BCS theory” are hairier. In a metal, the electron clouds of individual atoms meld into riverlike “bands.” The electrons flow through the bands in quantum waves in which their momenta are precisely defined but—thanks to quantum uncertainty—their positions are undetermined. In an abstract “momentum space,” the momenta of the most energetic electrons trace the so-called Fermi surface—typically a three-dimensional blob. Phonons bind electrons on opposite sides of the surface.

    Lay it on me.

    The Fermi surfaces of potassium-doped barium iron arsenide (left) map the momenta of its electrons. Superconductivity may arise because one surface can be shifted to cover another.


    Most physicists agree that the BCS theory cannot explain the cuprates, however, as phonons do not pull hard enough to produce their sky-high critical temperatures. For 24 years, researchers have debated what else makes the cuprates' electrons pair.

    The answer lies in waves of magnetism, some say. A cuprate, such as yttrium barium copper oxide, consists of planes of copper and oxygen ions arranged in a square pattern with the other elements sandwiched between the planes. To turn the compound into a superconductor, researchers must season, or “dope,” it with a little extra oxygen, which soaks up some of the electrons in the copper-and-oxygen planes. (See figure.)

    The undoped “parent compound” also displays an internal patterning called antiferromagnetism in which neighboring copper ions are magnetized in opposite directions. This pattern fades as doping increases and superconductivity sets in. However, fleeting ripples of it remain, and such fluctuations draw the electrons together, more or less replacing the phonons as the “glue,” many researchers argue.

    Others say that this scenario ignores the most important fact of the cuprates. “Band theory” calculations predict that the materials should be metals. In fact, they're insulators, as the electrons in the copper-and-oxygen planes repel one another so fiercely that they get stuck, one electron to one copper ion, in a “Mott insulator” state.

    As doping increases and the impasse eases, pairing emerges without any glue at all, some physicists say. In their “strong correlations” theories, pairing arises solely from quantum-mechanical symmetries and the interactions among electrons shuffling past one another like commuters on a crowded bus—even though the electrons only repel one another.

    A shifty solution

    As soon as the iron-based superconductors were discovered, physicists noted some uncanny similarities between them and the cuprates. The iron-based compounds are also layer-cake materials with planes of iron ions in squares. In them, superconductivity emerges as a parent material is doped with various elements. And, as in the cuprates, that parent material is antiferromagnetic, with neighboring rows of iron ions magnetized in opposite ways.

    The iron-based superconductors differ from the cuprates in an obvious way, however: The parent compounds are metals, not insulators. That fact and other data show that the electrons within them interact less strongly than those in the cuprates, making the materials easier to analyze, says Andrey Chubukov, a theorist at the University of Wisconsin, Madison. “The problem has a chance to be solved, and it's a matter of refining existing theoretical tools,” he says.

    Drawing on a torrent of data, theorists have sketched a scheme that seems to apply to materials as diverse as samarium iron arsenic oxide, calcium iron arsenide, and iron selenide. At its heart lies the superconductors' Fermi surface—the map of the momenta, or wavelengths, of the waves of electrons within them—which experimenters have traced using photons to blast electrons out of the materials in a technique called angle-resolved photoemission spectroscopy (ARPES). The results show that an iron-based superconductor actually has several ringlike Fermi surfaces. Crucially, one specific ring can be shifted as a whole to overlap another, an arrangement called “nesting.” (See diagram.) In fact, the ring must be shifted by a wavelength and in a direction that exactly match the spacing and orientation of the antiferromagnetic striping in the parent compound.

    That's no coincidence, Chubukov says. In the undoped compound, the nesting actually causes waves of electrons to interfere to make the antiferromagnetic pattern, much as ripples on a pond can interfere to make striking patterns. Then, in the doped compound, lingering ripples of antiferromagnetism zip between electrons to produce pairing. “The interaction that gives you the antiferromagnetism and the superconductivity is the same,” Chubukov says.

    Strong circumstantial evidence supports this scheme, physicists say. Using ARPES, researchers have shown that if they dope a material so much that one of the nested Fermi surfaces disappears, then so does the superconductivity. And scientists using neutrons to probe the materials have detected antiferromagnetic fluctuations of just the right character in the superconducting state.


    Cuprate superconductors (top) and newer ion-based ones (bottom) display some striking similarities as temperature and composition vary.


    A key detail remains to be confirmed, however. When pairs form on a Fermi surface, then they gather into a quantum wave of their own called an “order parameter.” The order parameters on the nested Fermi surfaces must have opposite signs, says Igor Mazin of the Naval Research Laboratory in Washington, D.C.

    That's because, discounting phonons, the electrons should only repel each other. But through some complicated quantum mechanics, that push can turn into a pull if exchanging a magnetic ripple also bounces a pair from one Fermi surface to another with an order parameter of the opposite sign. “If your interaction has the wrong sign, you can reverse it by making your order parameters have opposite signs,” Mazin says. “It's a bit mathematical; it's not so physical.”

    No one has proved experimentally that the order parameters on the two Fermi surfaces have opposite signs, says Michael Norman, a theorist at Argonne National Laboratory in Illinois. “My impression is that sometime this year, this will be cleared up,” he says, although he cautions that surprising results are emerging all the time.

    Strong dissent

    Some researchers doubt that this scheme gets to the crux of the physics in the iron-based superconductors. Several pieces of data show that the electrons in the materials interact as strongly as those in the cuprates do, says Steven Kivelson, a theorist at Stanford University in Palo Alto, California. For example, in the metallic state, their conductivities are as low as 1% of those in typical metals, suggesting that the electrons impede one another enough to spoil quantum waves of definite momentum.

    But if that's the case, the “nesting” model of antiferromagnetism goes out the window, says Qimiao Si, a theorist at Rice University in Houston, Texas. Si thinks the antiferromagnetism originates in the tangled physics of the jammed-up Mott insulator state, even though the iron-based compounds are never in that condition. “The system could be on the verge of the Mott [insulator] transition,” he argues.

    At any rate, the iron-based materials offer little insight into their cuprate cousins, says Philip Anderson, a theorist at Princeton University and a champion of the strong-correlations approach. “To take [them] as giving you information about the cuprates is to try to reconstruct the human figure from a cubist painting,” he says. The essence of the cuprates remains their evolution from the Mott insulator state, Anderson says.

    But others argue that if the emerging portrait of the iron-based superconductors holds up, then similar physics may explain the cuprates, which also have nested Fermi surfaces. The Mott state in the cuprates would then be irrelevant, says Dung-Hai Lee, a theorist at the University of California, Berkeley. “The iron-based superconductors liberate us from the belief that the Mott physics is essential for high-temperature superconductivity, which is what has kept us stuck for such a long time,” he says.

    Even if the current conception of the iron-based superconductors is correct, physicists will still have to fill in a huge amount of detail before they have a theory as precise and powerful as the BCS theory—and many doubt they'll ever have one. So it's far too early to write the book on the iron-based superconductors. But given what physicists have learned about the iron-based materials so far, some say it's not too early to start revising the saga of the cuprates.

  13. Space Science

    NASA Dives Into Its Past to Retrieve Vintage Satellite Data

    1. Heather Pringle*

    Once forgotten or erased, 1960s-era satellite images are being salvaged from old equipment and proving valuable in climate and space science.

    On 23 September 1966, NASA's Nimbus II satellite soared over Earth in a polar orbit every 108 minutes, taking pictures of cloud cover and measuring heat radiated from the planet's surface. The data documented the extent of polar ice shelves and the paths of two typhoons, but like thousands of other Nimbus II records, the information was originally stored on analog tapes and later forgotten for decades.

    Then last month, researchers working out of an abandoned McDonald's restaurant on the grounds of NASA Ames Research Center in Mountain View, California, recovered the Nimbus data from that day in 1966, creating a photo mosaic of the globe 43 years ago. The resulting image is the oldest and most detailed from NASA's Earth-observing satellites. It's also the latest success story in what researchers call techno-archaeology: pulling data from archaic storage systems. Once forgotten and largely unreadable with modern equipment, old data tapes are providing researchers with new information on changes in the surfaces of Earth and the moon.

    The recovered Nimbus II image, georectified and overlaid on Google Earth, significantly pushes back key climate data sets. Until now, researchers had little satellite data prior to 1979. But Nimbus II captured some 2457 records—including visible light and infrared information—over a 9-month period, beginning in May 1966. Moreover, researchers at the Lunar Orbiter Image Recovery Project (LOIRP) in Mountain View who have been methodically tracking down tapes from early spacecraft are opening an even larger window on the past. They have now located tapes from Nimbus I, III, and IV, launched in 1964, 1969, and 1970, respectively. “The period from the 1940s to the 1960s was a cooling interlude,” says Dennis Wingo, co-team leader of LOIRP, “so to have heat balance and thermal maps of the Earth from this period, and to be able to compare these to today, should yield a lot of insights.”

    Sixties icon.

    Satellite data from 23 September 1966 were used to create a thermal map of Asia and show very high, cold clouds over the Indian Ocean in blue and purple and warmer areas such as the Arabian peninsula in orange.


    Already, the rediscovered Nimbus data are creating a stir among climate scientists. Walt Meier, a research scientist at the National Snow and Ice Data Center in Boulder, Colorado, says the finds promise to shed new light on the problem of declining sea ice. “A lot of Nimbus data was collected in the months of August and September, which is when you have the minimum sea ice in the Arctic and the maximum in Antarctica,” Meier notes. “So the hope is that once [LOIRP] gets all this data processed, we could take a look at the ice edge during this period and work out sheet-ice extent on a monthly average basis back to the mid-1960s.”

    Such scientific interest shows the importance of NASA's early mission records. But during the 1980s, the agency lost much of its old high-quality data. Its early tracking stations recorded satellite data on high-resolution master tapes that used whale oil to bind iron particles to the acetate. The whale oil made the tapes far more durable, but when commercial whaling was phased out in the mid-1980s, NASA couldn't get such long-lasting tapes. So it reused old ones. NASA engineers taped over some 200,000 previously recorded master tapes, including high-resolution records from spacecraft as diverse as early Landsat satellites and Apollo 11, and preserved only low-resolution copies. “A huge amount of data was lost,” says Wingo.

    NASA also gave away as government surplus the Ampex tape drives—sophisticated versions of old videotape recorders—needed to play back surviving master tapes. Nancy Evans, an engineer and scientist at the Jet Propulsion Laboratory (JPL) in Pasadena, California, obtained four of the aging drives on her own and eventually stored them in her garage in Sun Valley, California, hoping to raise funds one day to rebuild them. “These were the last four in existence,” says Evans. “I later found out that most of these FR-900 drives were dumped into the ocean to make coral reefs.”

    Evans also saved some 1500 master tapes from five Lunar Orbiter missions launched between 1966 and 1967. The tapes were slated to be recycled, but Evans stowed them away at a JPL warehouse. “I thought it was a fabulously worthwhile data set,” she says.

    In 2007, as NASA drew up now-scuttled plans to send a new crewed mission to the moon, Wingo and colleague Keith Cowing learned of the existence of both the preserved tapes and the tape drives. They contacted Evans, who had since retired, and retrieved the 454-kilogram tape drives from her garage. Each drive is the size of a large refrigerator and was furry with dust and grime.

    McMoon project.

    Working from old tapes in an abandoned McDonald's restaurant, researchers recovered images from the 1960s Lunar Orbiter, including a close-up of Copernicus Crater on the moon (middle) and an earthrise (bottom).


    The LOIRP team obtained $750,000 from NASA and private enterprise and enlisted the assistance of a retired Ampex engineer. They cleaned, rebuilt, and reassembled one drive, then designed and built equipment to convert the analog signals into an exact 16-bit digital copy. “It was like dumpster diving for science,” says Cowing, co-team leader at LOIRP.

    In November 2008, the team recovered their first image: a famous picture of an earthrise taken by Lunar Orbiter 1 on 23 August 1966. The team's new high-resolution version was so crisp and clear that it revealed many previously obscured details, such as a fog bank lying along the coast of Chile. “We thought if the Earth's surface looks that good a quarter of a million miles away, what does the moon's surface look like 100 miles beneath it?” says Cowing.

    So they recovered additional images of the moon itself. With a resolution of 1 meter per pixel, these old images compare well with current Lunar Reconnaissance Orbiter photos, which have an average resolution of 1.21 meters per pixel. Most of the old images were taken under optimum illumination conditions, says Paul Spudis, a senior scientist at the Lunar and Planetary Institute in Houston, Texas, and “are invaluable both as a scientific and historical resource” for detecting changes on the moon. For example, by comparing the number of small impact craters per unit area in 1966 with the number seen now, analysts will be able to estimate how often asteroids fall in specific areas of the moon, establishing the risk that a future human crew working there would face.

    Some of this analysis could even take place in high school or college classrooms, says John Olson, a director in NASA's Exploration Systems Mission Directorate in Washington, D.C., who dreams of “giving students a modern snapshot of a location on the moon and the corresponding LOIRP image” for them to compare.

    Certainly, the value of the old mission tapes is no longer in doubt. “By using modern image processing, the LOIRP effort is giving us a window on the moon we have never had before,” says S. Alan Stern of the Southwest Research Institute in Boulder, a former NASA associate administrator in charge of all science missions. The larger message to the scientific community is clear, says Meier. “Don't throw away data unless you are absolutely, positively sure you don't need it anymore. Being a pack rat can be a good thing.”

    • * Heather Pringle is a contributing editor at Archaeology magazine.

Log in to view full text

Log in through your institution

Log in through your institution