# News this Week

Science  16 Apr 2010:
Vol. 328, Issue 5976, pp. 290
1. Nuclear Physics

# Discovery of 'Missing' Element 117 Hints at Stable Isotopes to Come

1. Lauren Schenkman

Russia strikes again. In the past decade, the Joint Institute for Nuclear Research in Dubna, Russia, has bagged new elements 113, 114, 115, 116, and 118 by firing up a fantastically intense beam of neutron-heavy calcium-48 isotopes and blasting away at the periodic table's radioactive actinide elements. Last week in Physical Review Letters, a multi-institution team there announced that it had filled a gap by making element 117 as well.

“They devoted very, very long beam times and very hard work, ” says nuclear chemist Heino Nitsche, who leads the heavy-element group at Lawrence Berkeley National Laboratory in Berkeley, California. At other labs, Nitsche says, heavy-element scientists vie with other experimenters for beam time, but Dubna physicists enjoy a cyclotron largely dedicated to element-hunting. “You won't find that anywhere else in the world, ” he says.

For decades, the new-element sweepstakes has been a three-way race. Beginning in 1940, the Berkeley lab dominated the field, claiming or sharing credit for all elements except for one from 93 through 106. In 1981, the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, pulled ahead, planting flags on elements 107 through 112, the recently named copernicum.

Even with stretches of beam time available at Dubna, going after 117 required “experimentally, an enormous tour de force, ” says nuclear physicist Konrad Gelbke, director of the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University in East Lansing. To get to 117 protons from calcium's 20, Dubna physicists needed the 97 protons in the devilishly-hard-to-synthesize element berkelium. Nuclear chemists at the world's most intense neutron source, the High Flux Isotope Reactor at Oak Ridge National Laboratory in Tennessee, spent 250 days scraping together 22.2 milligrams of the stuff—about the size of a fingernail paring—and another 90 days purifying it to one part in 10 million. Then the clock began to tick: Berkelium's half-life is 320 days.

The hot material's next stop was Russia's Research Institute of Atomic Reactors in Dimitrovgrad, where scientists deposited it on a thin film of titanium. Then it went on to Dubna, where physicists pummeled the target with 7 trillion calcium-48 ions per second, day and night for 5 months. A gas-filled separation chamber diverted atoms blasted off the target into an array of detectors. From thousands of potentially interesting events, the physicists pinned down just six atoms of element 117.

To do so, they looked at the chains of other elements produced as the radioactive atoms decayed toward stability. An isotope of 117 with 177 neutrons, for example, spits out alpha particles to metamorphose first into daughter nucleus 115 and later into dubnium (105) before fissioning. The elements in this chain—115, 113, 111, and so on—had all been made before. But the new versions had more neutrons than earlier ones did and were strikingly longer-lived—6000 times as long, in the case of one isotope of element 111.

Those results fit with theorists' current picture of heavy-element nuclei, says Witold Nazarewicz, a theoretical physicist at Oak Ridge and the University of Tennessee, Knoxville. The theory predicts that certain so-called magic numbers of protons and neutrons confer extra stability to a nucleus. A magic number at 184 neutrons, for example, ought to anchor an “island of stability,” a still-to-be-discovered group of long-lived superheavy isotopes that hold together for days, years, or even millennia. (In contrast, superheavy elements made so far have half-lives of fractions of a second.) The new Dubna results showing that added neutrons increase the stability of heavy elements “suggest that the theory knows what it's doing, ” Nazarewicz says. “It's encouraging.”

Physicists at all three facilities agree that the way to reach the island of stability is by producing heavier isotopes of known elements. That will require superb beams of radioactive elements unlike any now achievable, says Sigurd Hofmann, the head of heavy-element research at Darmstadt. Such beams may become available at labs like NSCL's planned Facility for Rare Isotope Beams, currently in the conceptual design phase, but they are still decades away, Hofmann says.

Meanwhile, Nazarewicz says, efforts to create new elements will help theorists test their models of nuclear structure. But Dubna's spurt of contributions may just have come to an end: Researchers say the lab has run out of useful actinide targets for its calcium beam. To get element 119 would require working with einsteinium, “a very complex task” that Dubna likely won't attempt, says Dubna's director, nuclear physicist Yuri Oganessian. Element 120 is definitely out of range, he says.

That opens the door to other approaches. The Darmstadt group plans to confirm 116 this summer by training a calcium beam on a radioactive curium target, says Hofmann; the technique could lay the groundwork for creating 120 from curium with a chromium beam. The Berkeley team, which was devastated in 2002 when it had to withdraw its claim on element 118 after critical data turned out to have been fabricated (Science, 19 July 2002, p. 313), is back in the game, recently confirming Dubna's element 114 with a calcium beam and plutonium target. And a newcomer—the superheavy element lab at the Institute of Physical and Chemical Research (RIKEN) in Japan—has been instrumental in confirming some of Darmstadt's finds.

Confirmation is key to the discovery process: Under international rules, a lab may not name a new element until a competitor repeats the finding. That could take years for element 117, says Dubna team member Dawn Shaughnessy, a nuclear chemist at Lawrence Livermore National Lab in Livermore, California. “It's hard for someone to go to their management and say, ‘I want to do this long experiment just to verify this person's discovery,’” she says. Still, confirmation will come. “There may be rivalry, … but we all have to work together if anyone wants credit.”

2. U.S. Science Policy

# Obama Picks Pragmatists for New Bioethics Panel

1. Constance Holden

President Barack Obama named the members of his bioethics commission—headed by two university presidents—last week. The 12-member group, selected more for practical advice than for philosophizing, as the last one was prone to, will hold its first meeting in Washington, D.C., in July.

Headed by Amy Gutmann, president of the University of Pennsylvania (Penn), the new Presidential Commission for the Study of Bioethical Issues succeeds the old President's Council on Bioethics, disbanded last June. Gutmann and her vice chair, Emory University President James Wagner, were named in November. Although the label is longer, the group itself is leaner, with a dozen members instead of the 18 under President George W. Bush.

“Previous commissions have been somewhat too philosophically oriented,” presidential science adviser John Holdren said last week. Bush's council, headed successively by bioethicists Leon Kass of the University of Chicago and Edmund Pellegrino of Georgetown University, produced lengthy reports on topics such as “Being Human.” The new commission, in contrast, is expected to offer concrete policy and legislative advice. Says White House aide Rick Weiss: “The hope is this will be perhaps a little more nimble.” He also says the commission is probably “unique historically” for including several federal employees. Because the president wants practical advice, he wanted people “close to the ground” who understand the government's labyrinthine ways, Weiss says.

Gutmann, 60, is a prolific scholar and has an impressive reputation as a philosopher and political scientist. Prior to going to Penn in July 2004, she served as dean and then provost at Princeton University. She'll preside over an eclectic group of physicians (including a Franciscan friar), scientists, philosophers, and lawyers, as well as a patient advocate—the wife of boxing great and Parkinson's victim Muhammad Ali.

Gutmann is one of four commission members who are also fellows at the Hastings Center in Garrison, New York. She's “a fascinating choice as chair,” says Hastings President Thomas Murray, who calls her “brilliant, … delightful, … a great leader.” Her vice chair, Wagner, is an engineer and former medical devices researcher who has “championed the role of ethics” in Emory's mission, according to a White House statement.

“To me, it's a very highly qualified, middle-of-the-road panel,” says Penn bioethicist Arthur Caplan. Although some criticized the Bush bioethics council for being stacked with conservatives, conservatives don't seem inclined to attack the Obama selections. “I don't like the politics of most of them, but the records of achievement are great,” Bush council member Robert George, a Catholic legal scholar at Princeton, told the Christian news magazine World.

It's not known what the commission will tackle first, but as Caplan points out, the newly passed health care legislation offers much food for discussion on matters relating to privacy, limits of coverage, and “the much-despised word ‘rationing.’” And that raises a crucial issue in the opinion of bioethicist Norman Fost of the University of Wisconsin, Madison. Fost observes that for all their expertise on cloning, bioterror, underserved groups, or the rights of research subjects, none of the commission members is deeply conversant with the economic issues surrounding health care financing, cost control, or rationing of care. Yet, he says, “the overwhelmingly most serious issue in health … is costs.”

3. Fusion Science

# Report Calls for Improvements At Livermore's Giant Laser

1. Eli Kintisch

Will the world's biggest laser—designed to simulate the nuclear fusion that occurs in stars and thermonuclear weapons—ever work as advertised? A new U.S. government audit of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory in California says the $4 billion behemoth faces “scientific and technical challenges and management weaknesses.” But scientists associated with the project believe that the machine will do great science if Congress gives it a chance to flex its muscles. NIF's 192 lasers focus on a thimble-sized target in which various types of hydrogen atoms, under incredible heat and pressure, are meant to undergo fusion. That accomplishment, called ignition, would allow researchers to better monitor aging nuclear weapons, understand processes in the cores of stars and planets, and point the way toward clean, cheap energy. The project has encountered repeated delays since construction began in 1997, however, and its cost has more than doubled. Last year, it was formally dedicated (Science, 17 April 2009, p. 326) with the hope of performing ignition experiments sometime in 2010. But the path to ignition still has some bumps, says the Government Accountability Office (GAO) in a report issued last week.* Although GAO said the project had “made progress,” among the serious problems it identified was the machine's capability to shoot at full energy. Congress funded NIF to fire at 1.8 megajoules (MJ). But GAO found that problems with laser optics that were identified years ago have continued to limit the machine's 192-beam shots to 1.3 MJ or less. That shortfall is serious because higher energies improve NIF's chances of success. (At the same time, the laser's optical equipment is more prone to damage at higher energies, and NIF is utilizing a 4-month pause to work on the problem.) Indeed, said GAO, experts “are concerned” that energy losses or damaged optics would doom ignition experiments, undermining NIF's value in weapons science. GAO also said that the Department of Energy's National Nuclear Security Administration (NNSA), which funds the project, had failed to manage it properly. One major example: NNSA took 4 years to appoint a standing review committee after outside advisers recommended the need for independent oversight. Raymond Jeanloz, a physicist at the University of California, Berkeley, thinks government auditors have given the project a bum rap. In the past 5 years, scientists at NIF developed new means of examining and repairing glass optics without replacing them, says Jeanloz, who hopes to use the machine to study processes in the interior of planets. The changes give NIF a fighting chance of achieving its 1.8-MJ goal. NIF officials also say that it may be possible to achieve ignition at lower energy. Even at 1.3 MJ, Jeanloz points out, the laser is roughly 40 times more energetic as any other such machine. “You want the best value for the taxpayer, of course, … but we really don't know what will work at these energies.” NIF officials defend their management decisions. And they face little heat from federal lawmakers, who can do little to influence the project at this point short of shutting it down. So Jeanloz says it's time to let the scientists “do cutting-edge science” and then “see what happens.” 4. ScienceNOW.org # From Science's Online Daily News Site When Social Fear Disappears, So Does Racism Children with a genetic condition that quells their fear of strangers don't stereotype based on race, according to a new study. The findings support the idea that prejudice stems from fear of people from different social groups, although some researchers question how well the new study supports that conclusion. Cholesterol Genetically Linked To Eye Disease Two genetic studies involving thousands of participants suggest that age-related macular degeneration, an eye disease common among the elderly, is tied to a gene that helps regulate “good” cholesterol. The studies present the first genetic evidence of a link between cholesterol and the disease, and they may lead scientists to identify new targets for therapy. Does Our Universe Live Inside A Wormhole? A long time ago, in a universe much larger than our own, a giant star collapsed. Its implosion crammed so much mass and energy together that it created a wormhole to another universe. And inside this wormhole, our own universe was born. It may seem fantastic, but a theoretical physicist claims that such a scenario could help answer some of the most perplexing questions in cosmology. Earth-Like Planets May Abound In Milky Way Observations of formerly sunlike stars called white dwarfs suggest that the overwhelming majority of them once harbored at least one rocky world. And because sunlike stars could account for up to half of the Milky Way's population of several hundred billion suns, that means thousands or even millions of civilizations might inhabit our galaxy. For the full postings and more, go to news.sciencemag.org/sciencenow. 5. Newsmaker Interview # Sean Carroll and the Evolution of an Education Maven 1. Elizabeth Pennisi With a paper last week in Nature, Sean Carroll would seem to be at the top of his game as a researcher. Yet his career is about to take a new tack: The day before the paper appeared, Carroll, a molecular biologist at the University of Wisconsin, Madison, was named vice president for science education at the Howard Hughes Medical Institute. HHMI President Robert Tjian says it's a tribute to his wide-ranging interests and to the success Carroll has enjoyed in both arenas. “He most closely matched the totality of attributes that we were searching for,” says Tjian. A member of the U.S. National Academy of Sciences, the 49-year-old Carroll is a pioneer in the field of evolutionary development. (His most recent paper describes how the polka dots on a fruit fly wing were patterned according to the distribution of a molecule involved earlier in the fly's development.) He has become increasingly engaged with public education over the past 6 years. His Remarkable Creatures: Epic Adventures in the Origins of Species was a 2009 National Book Award finalist, and last fall he began writing a monthly column for The New York Times. Last month, he received the 2010 Stephen Jay Gould Prize for his outreach efforts. Already a longtime HHMI investigator, Carroll this fall will succeed Peter Bruns as head of the institute's$75 million education portfolio.

Science educator Toby Horn of the Carnegie Institution for Science in Washington, D.C., is thrilled with Carroll's new job. “He's really there for teachers,” she says. And biologist Susan Wessler of the University of Georgia, Athens, who has had HHMI support for her undergraduate teaching but was worried because HHMI has recently reduced support for that program, is also pleased. “It sends a very strong message that they are serious about science education. For those of us who had concerns, we are assuaged.”

Science caught up with Carroll last week to ask him about his new job.

Q:What's the most effective way to do science education?

S.C.:It's a big landscape. There's a continuum there, which is young kids that you want to inspire to have a curiosity about science, slightly older kids that if they are curious about science, you want to encourage them on that path, and then kids who are committing to paths in science, [making sure] that they get inspiring and effective instruction, mentoring, hands-on research experience, et cetera. That's why Hughes is doing lots of different things, as is the National Science Foundation [NSF], as are other organizations.

Q:How does NSF's mission differ from what HHMI is trying to do?

S.C.:HHMI research funding operates on a fundamentally different principle from government funding by backing people, not specific projects. And HHMI explicitly encourages major risk-taking. On the education front, HHMI has the same latitude. Think of HHMI as a venture capitalist. We and our grantees can try a lot of different ideas and approaches.

Q:What has been your most rewarding science education experience?

S.C.:I think the most rewarding for me has been contact with teachers. Now that's probably mostly high school teachers. I think they are a really important and valuable constituency.

Q:What are their biggest concerns?

S.C.:Well, we probably were brought together over the teaching of evolution. That was issue [number] one, … because biology without evolution is kind of like physics without gravity. It's also sort of a canary in the coal mine for the state of science education. There's so much propaganda against evolution, but you see the same sort of techniques being used against climate science or stem cells or whatever it might be.

Q:What are your plans for Hughes?

S.C.:I would say one of the most obvious differences, I think, between the research community that I'm part of and the education community is that in the research community, when anyone has a new tool, a new widget, it often spreads like wildfire. But I think in education, it's a little different. I think campuses have a more local focus. And yet, when it comes to teaching, obviously, what works in Alaska can work in Arkansas and can work in Pennsylvania. I think Hughes can play a role in disseminating good ways of doing things. One of my interests is general public science education, so I think we'll be looking for ways to expand our presence there.

Q:Has the amount of time you've actually spent doing research changed in the last 5 years, and will it change again in this new job?

S.C.:I'm going to spend 80% of my time in the science education role with Hughes. I'll maintain a lab, but I know there's a clear delineation of where my effort's going to be. The University of Wisconsin has released me from teaching. So I'm not going to be in the classroom here.

Q:Why would a master educator abandon the classroom but remain active in the lab?

S.C.:It is not a matter of abandoning [the classroom], it is really a matter of scheduling. It is not realistic to carry out this job and to teach on a typical Monday, Wednesday, Friday schedule. Moreover, it is very important to recognize that classroom teaching is not the only way to contribute to undergraduate education; in my case books and textbooks, articles, DVDs, TV programs, and public lectures all reach undergraduates here at Wisconsin and beyond. So, no, it is not a matter of valuing research over teaching, it is a matter of managing a breadth of activities in the time available.

6. Agriculture

# Biotech Crops Good for Farmers and Environment, Academy Finds

Fourteen years after genetically engineered crops began to take off in the United States, the overall benefits to farmers are clear, according to a new report from the National Research Council (NRC) of the National Academies. The shift from conventionally grown crops has paid off economically and environmentally, says the panel. “We can stop arguing about whether the environmental and economic impacts are significant,” says agricultural economist Nicholas Kalaitzandonakes of the University of Missouri, Columbia, who was not on the panel.

The debate about impacts of genetically engineered crops on farms has been driven in part by the variability of agriculture. Whether a study shows that a farmer benefits from going biotech can depend on the particular crop, location, and factors such as the abundance of pests. In the past, some researchers and advocates have cherry-picked data to back their views about whether or how much the technology helps farmers, Kalaitzandonakes says.

The NRC panel sifted through the peer-reviewed literature before coming to its main conclusion. Most of the impacts are relatively straightforward, at least in principle. When corn is enhanced with a bacterial gene for a toxin that kills insects, for example, farmers can spray less of dangerous insecticides, which is good for their bottom line and for wildlife. Another common approach—soybeans outfitted with a gene that renders them immune to the herbicide glyphosate—reduces the need to till fields to control weeds, resulting in less soil erosion. The overall amount of herbicide used has increased because glyphosate-resistant biotech crops can be sprayed with impunity, but glyphosate has generally replaced more toxic herbicides.

Still, many effects need to be better studied. Reduced tillage could offer the “largest single environmental benefit of GE crops,” the panel found, because it should mean less sediment, fertilizer, and pesticides washing into streams. But this hasn't been proven, so the panel recommends that the U.S. Geological Survey investigate the impact of reduced tillage on water quality.

The panel also warns that existing gains aren't guaranteed. For instance, insect or weed resistance could render genetically engineered crops ineffective and force farmers to resume using more toxic chemicals (Science, 25 May 2007, p. 1114). Economist Paul Mitchell of the University of Wisconsin, Madison, agrees that more needs to be done to slow the evolution of resistant weeds, such as spraying more than one kind of chemical. “Glyphosate is a once-in-a-century herbicide,” Mitchell says, referring to its relatively benign side effects. The risk of losing it is a major worry, he says, although new kinds of crops could help thwart resistance.

Another concern is that industry mergers and the dominance of a few players might stifle competition, an issue the Department of Justice is examining. “If we're going to spur innovation, we need a very competitive industry,” says economist David Ervin of Portland State University in Oregon, who chaired the panel.

Biotech corn, soy, and cotton are firmly entrenched in the United States, but the report could help win support for other engineered crops, such as wheat and potatoes, observers say. And it could help inform policymakers in countries trying to weigh environmental benefits and risks of biotech crops. “Most of these countries around the world are looking at us in terms of resolving the debate,” Kalaitzandonakes says.

• * The Impact of Genetically Engineered Crops on Farm Sustainability in the United States. The National Academies Press, 2010.

7. ScienceInsider

# From the Science Policy Blog

Prominent Old Testament scholar Bruce Waltke has been forced to resign from the Reformed Theological Seminary, an evangelical seminary with a branch in Oviedo, Florida, after saying evangelical Christianity is going to be sidelined as a “cult” if it denies evolution. A video of the talk was made during a workshop at the BioLogos Foundation.

Ethiopia has launched its first science academy. The independent Ethiopian Academy of Sciences in Addis Adaba will provide advice to the government and promote science, technology, and science education. Demissie Habte, a pediatrician, has been elected president.

The United States has forsworn nuclear attack against nonnuclear countries as long as they comply with their nonproliferation commitments under different international treaties. The new policy, part of a long-awaited Nuclear Posture Review, would preclude launching a nuclear offensive against any country in retaliation to a chemical or biological attack.

A resounding majority of members of the London-based Royal Institution have voted to retain its current governing council. The vote quashes an effort to turn back the council's recent dismissal of controversial director Susan Greenfield.

U.S. Energy Secretary Steven Chu said he plans to proceed with the termination of Nevada's Yucca Mountain nuclear waste repository despite congressional opposition. “We believe we do have the legal authority to do this,” Chu said.

After ScienceInsider asked readers for ideas, blog commenters proposed the following names for newly discovered element 117, among others: StevenColbertium, Perelmanium (after the mathematician Grigori Perelman), Dubnaium (after the town in Russia where the element was discovered), and Chrysanthemum.

For the full postings and more, go to news.sciencemag.org/scienceinsider.

8. Astronomy Education

# Telescopes for the People

1. John Bohannon

The International Year of Astronomy (IYA) 2009 has come and gone, but Rick Fienberg is still catching his breath. As leader of the Galileoscope project, one of the most ambitious parts of the global IYA campaign, his work was supposed to be wrapped up by now. The original goal was to put telescopes in the hands of the millions of people attending IYA events. But then the global financial crisis hit. The scientists on Fienberg's team were forced to become instant entrepreneurs to keep the Galileoscope project alive. One “insane” year later, they've pulled it off. “It has had a truly global impact,” says Pedro Russo, the coordinator of the IYA based in Garching, Germany.

The ultimate aim of the IYA was “to help the citizens of the world rediscover their place in the universe.” What better way to do that than give them their own telescopes? Fienberg says that when he proposed the idea at an astronomy meeting 3 years ago, “it was immediately embraced.” And as the long-time editor of Sky & Telescope magazine, Fienberg had all the right connections to make it happen. The plan was to use “start-up money from a major donation,” he says, and then partner with “an existing commercial telescope manufacturer so we could take advantage of their distribution network.”

The device had to be powerful enough for people to see what Galileo first saw 400 years ago—the lunar landscape, the rings of Saturn, the moons of Jupiter—but also cheap enough to distribute, says Fienberg, “especially in developing countries.” He was joined by Stephen Pompea, an astronomer at the U.S. National Optical Astronomy Observatory in Tucson, Arizona, and Douglas Arion, an astronomer at Carthage College in Kenosha, Wisconsin.

Because seeing the innards of the telescope would be as important for education as viewing celestial objects, the instrument would be taken apart and put back together on a daily basis—and yet it must cost no more than $30. (Charitable support would drive the price of the telescopes below$10.) The solution was a plastic clamshell design with the lenses locked in place by internal slots. Engineering by their manufacturing partner, Thomas Smith, the owner of U.S. company Merit Models, proved crucial, says Arion, ensuring that “all the tolerances were met [and] the parts fit together well.”

The final instrument was far more powerful than Galileo's telescope. Rather than a 20-fold magnified view of 10 arc minutes of sky—far narrower than the face of the moon—the Galileoscope was designed to magnify as many as 50 times and comfortably take in the full moon in a single view. The lenses of the Galileoscope also correct for distortions called chromatic aberrations that Galileo's original telescope produced.

By late 2008, they had a prototype Galileoscope ready to go. And that's when the financial floor fell out from under them. In the wake of the financial crisis, says Fienberg, “the donation didn't materialize, and telescope manufacturers lost interest in working with us on a project that wasn't designed to make any real money.” At that point, they might have thrown in the towel, but the Galileoscopes were already locked in as a “cornerstone project” of the IYA, says Fienberg. “So three of us formed our own new company, Galileoscope LLC.”

The business faced a daunting challenge. “We had no cash, no capital, and with no profit to be made and no assets, no realistic way to raise funds,” says Arion. So the trio spent a significant amount of their own money to create the tooling to manufacture the Galileoscopes. They built a Web site that could handle orders, “and then we bootstrapped from there,” using funds from orders to pay for inventory, says Arion. “That's the primary reason why the delivery schedule has been, shall we say, sporadic.” Fienberg, Pompea, and Arion prefer not to disclose how much money they each “loaned” the Galileoscope project, but they hope “to get it back out” in the near future.

By the time the IYA launched in January 2009 with global fanfare, the Galileoscopes were far from ready. The first orders weren't met until July. Some of the gap was filled by parallel efforts in the United Kingdom and Japan, which distributed an existing telescope kit to schools in Asia and Africa.

After the summer, huge waves of Galileoscopes finally went out around the globe. Norway bought 15,000 of them. Brazil bought 20,000. By the end of last year, 140,000 Galileo scopes were delivered. Orders for another 40,000 will be fulfilled in the coming weeks, pushing the total to 180,000. “Pretty good considering the late start we got,” says Fienberg. And because most of the telescopes went to “schools, planetariums, and science museums, they'll be used by dozens or hundreds of people each,” he adds.

The Galileoscopes are already taking on a life of their own. “This spring, 15,000 telescopes will be distributed to teachers nationwide,” says Pompea, with workshops organized through the National Earth Science Teachers Association. Meanwhile, Chi-kwan Chan, an astrophysicist at Harvard University, is preparing to take a Galileo scope across North America by bicycle. He'll be teaching astronomy, measuring light pollution, and sharing astronomical photo graphs on a live blog (www.bikexus.blogspot.com). “Yes, I am a geek,” says Chan.

But the future of the Galileoscope project is uncertain. The hope is to keep producing the telescopes, “but we can't maintain the level of volunteer effort we've put in during the past year,” says Fienberg, who is now director of outreach for the American Astronomical Society. The team is hunting for an organization or company willing to take over their labor of love. So far, no takers.

9. Neuroscience

# New Guidelines Aim to Improve Studies of Traumatic Brain Injury

1. Greg Miller

It's still dark outside as neurosurgeon Geoffrey Manley greets a visitor in the lobby of San Francisco General Hospital. “It's been a busy night,” Manley says. An overnight rain has made the roads slick. “We just got a guy who was ejected from the back seat of a car,” Manley says. “He wasn't wearing a seat belt.”

The U.S. Centers for Disease Control and Prevention estimates that 1.7 million Americans suffer a traumatic brain injury (TBI) each year in car accidents, falls, or other mishaps. Unfortunately, the doctors who treat them have limited options. Despite promising leads from animal research, dozens of drugs intended to protect the brain after injury have failed in clinical trials.

Manley thinks part of the problem is an outdated system used to classify TBI patients for trials. (For a perspective on obstacles to drug development, see the 14 April issue of Science Translational Medicine). Manley has been a leading force in an initiative to improve the way TBI patients are characterized for clinical trials and other studies. A rough draft of new guidelines was released on 1 April by one of the project's sponsors, the National Institute of Neurological Disorders and Stroke,* and they will be described in detail later this year in a special issue of the Archives of Physical Medicine and Rehabilitation. Manley, who co-directs the Brain and Spinal Injury Center at the University of California, San Francisco, recently received a $4.1 million Grand Opportunities Grant from NINDS to study at four U.S. medical centers whether it's feasible to collect up to 500 pieces of information on individual TBI patients and to standardize brain scans and other measurements so they can be compared across centers. If it succeeds, the project's leaders hope the methodology will be widely adopted. One of the primary tools now used to assess TBI patients, the Glasgow Coma Scale (GCS), has been in use since the 1970s. It rates patients' eye movements, limb movements, and speech. Scores range from 3 (comatose) to 15 (fully awake and responsive). Doctors describe patients' injuries as mild (13 or above), moderate (9 to 12), or severe (8 or below), and researchers use these groupings in clinical trials and observational studies. Sorting patients by their GCS scores makes sense when you're triaging patients in the emergency room at 3:00 a.m., says Manley, but it's an awfully coarse tool for research: “We're taking one of the most complex, heterogeneous disorders in the most complex organ in body and dumbing it down to mild, moderate, and severe.” Two people with the same GCS score can have very different brain injuries, Manley says. One patient, for example, might have a subdural hematoma, an expanding pool of blood between the protective layers surrounding the brain, whereas another might suffer from diffuse axonal injury: extensive damage to the white matter tracts that convey signals from one brain region to another. Grouping together two such patients in a drug trial may dilute any therapeutic effects, because a drug that helps patients with subdural hematoma would likely have a mechanism very different from one that helps patients with diffuse axonal injury. Several types of TBI can easily be distinguished by CT scans, which have become routine in the decades since the GCS was developed. Although the scans are often used to diagnose patients in the hospital, they're rarely used to sort patients for clinical trials or other studies, says Manley, who would like to change that. This can be tough to do retrospectively, but part of the goal of his pilot study is to standardize CT scans and other measurements taken shortly after an injury so that they can be used to sort patients for research. Deciding which data are most useful for characterizing patients is one goal of the NINDS “common data elements” project, which is also sponsored by four other agencies, including branches of the Department of Defense and the Department of Veterans Affairs, whose interest in TBI has surged with the tide of soldiers returning home from Iraq and Afghanistan with head injuries. The first draft contains checklists for collecting several categories of patient information, from demographic details to neurological symptoms and CT results. Andrew Maas, a neurosurgeon at University Hospital Antwerp in Belgium, helped draft the new guidelines and hopes they can be applied globally to make it easier to compare findings across studies. He and colleagues recently analyzed data sets for 11 large TBI observational studies and clinical trials in Europe and North America. It was far more work than his team imagined because the studies differed in which variables they measured, how they measured them, and how they were coded in their database. “It took 10 person-years just to transform the data into a format we could work with,” he says. Still, the utility of the guidelines will depend on how they're used, says John Whyte of Moss Rehab, a rehabilitation center in Elkin Park, Pennsylvania. There needs to be a balance between standardizing data collection and bogging down researchers with long lists of data elements that may or may not be relevant for a given study, Whyte says. Meanwhile, as Manley leads a cluster of medical residents on rounds, each patient they visit illustrates how a life can be altered in an instant by a fall, a crash, or even a punch to the head. Some are likely to recover; others aren't. For all of them, better science can't come soon enough. 10. # Chasing a Disease to the Vanishing Point 1. Jennifer Couzin-Frankel Genetic testing is making a rare disease, familial dysautonomia, even rarer. At the same time, more tools than ever are available to study it. NEW YORK, NEW YORK—When suite 9Q in the neurology department emptied out a few years ago, Felicia Axelrod knew that this cluster of offices and exam rooms was destined to be hers. “I had to have it,” says Axelrod, a pediatrician at New York University Langone Medical Center in New York City, whose diminutive stature belies her resolve. She met with the neurology chair to press for a move from the third floor. “I was a pit bull,” she says. Axelrod was soon ensconced in 9Q—making her perhaps the only physician in the country whose office address is the same as the address of the gene for a disease that's consumed all 40 years of her career: familial dysautonomia, located on chromosome 9Q31. Familial dysautonomia (FD) brutalizes the autonomic and sensory nervous systems. Patients have difficulty swallowing, speaking, coughing, and walking; they lack sensitivity to pain, leaving them at risk of burns and broken bones; and their blood pressure swings from extreme highs to faint-inducing lows. As one researcher puts it, patients with FD are “at the mercy of their emotions” because their blood pressure and heart rate are improperly regulated. Excitement about a birthday party, or anxiety about a school test, can send them into paroxysms of retching, drooling, nausea, and soaring blood pressure, a state known as crisis. “The first crisis I saw, I got so scared,” says Horacio Kaufmann, a neurologist who works with Axelrod. “I thought the patient was going to explode.” Most physicians have never seen a person with FD. That's because nearly all of them find their way to Axelrod, who opened her FD clinic back in 1970. But there's another reason FD patients don't show up in waiting rooms: The rare disease has gotten even rarer, thanks to widespread genetic testing that has led prospective parents with the gene to avoid or terminate affected pregnancies. FD is almost exclusive to the Ashkenazi Jewish community. The FD gene was reported in January 2001, and within months the push for carrier testing began. The result: In 2009, only five new FD cases were diagnosed in the world, down from about 15 or 20 a year in the 1990s. FD is just one of a rapidly expanding set of diseases for which carrier testing is available or soon will be (see sidebar, p. 300). In 2001, the American College of Obstetricians and Gynecologists recommended that before having a child all couples be offered carrier testing for cystic fibrosis, the first such push to make carrier testing available to everyone. Last year, a California company called Counsyl began selling a genetic test for$349 that screens for mutations for more than 100 genetic diseases. Technology has advanced to the point that once an individual is being tested for one gene mutation, it's easy to include dozens more. Some of these diseases will become extraordinarily rare—as FD has—though they may never vanish completely.

What does this mean for patients and families living with these conditions, and for physicians and researchers who have dedicated their careers to them? The communities are better off but shrinking at the same time. “We're entering the era of rare disease research and treatment,” says Steven Walkley, a neuroscientist at Albert Einstein College of Medicine in New York City who has studied Tay-Sachs disease and related conditions. In August, the U.S. National Institutes of Health (NIH) awarded a consortium $3.5 million to develop gene therapy for Tay-Sachs. Last year, approximately 11 children in the United States were diagnosed with the disease, down from about 100 per year before prenatal testing began. The same trend affects FD. In Axelrod's waiting room, a toy wooden kangaroo and plastic stacking cups still sit on a miniature table with chairs, but few young children come through the door these days. The average age of patients is now 17. The Dysautonomia Foundation, the advocacy group in New York City that has funded Axelrod's clinic from the start, is struggling to raise money. At the same time, in the past 3 years the clinic has expanded, hiring Kaufmann and his wife, Lucy Norcliffe-Kaufmann, both of whom study autonomic syndromes, and filling a room with high-tech equipment. The group belongs to a newly minted NIH-funded consortium studying rare autonomic diseases and recently scored a grant from the U.S. Food and Drug Administration (FDA) to test a 40-year-old drug for Parkinson's disease in their patients. The irony is that the expanded resources serve a dwindling pool of FD patients. ## Untilled terrain When Axelrod began working on FD, half of her patients died by the age of 5; now half make it to 40. She and her husband, an obstetrician who delivered the first baby born to a woman with FD, in the late 1970s, have always lived across the street from the hospital, in an apartment complex Axelrod looks onto from her office window. Her oldest patient is now 65. “She's the only pediatrician who has patients who have gone through menopause,” says David Brenner, executive director of the Dysautonomia Foundation, “because she's had them since they were little kids, and she won't give them up.” Axelrod diagnosed Brenner's 22-year-old son Michael with FD when he was 2 years old. But after going it alone for so long, Axelrod concluded a few years ago that she needed help. Although the number of new FD cases had shrunk to close to zero, she was still treating several hundred teenagers and adults to whom she felt overwhelming responsibility. Meanwhile, the nature of the disease was shifting in ways she didn't understand. Patients were developing kidney failure, which Axelrod hadn't seen before. (Three have had transplants.) Some died suddenly of cardiac arrest, including, last month, a 28-year-old vacationing in Amsterdam with his parents. Axelrod wanted to find a physician with expertise in treating autonomic disease in adults. “A lot of people would say, ‘You're out of your mind because you're betting your career on a disease that's disappearing,’” says Kaufmann, an Argentinean with close-cropped gray hair and blue eyes who came to the United States in 1981. He had what he describes as a cushy job in an endowed chair at Mount Sinai Medical Center on the posh Upper East Side of Manhattan. He left it 2½ years ago, he says, after much “wining and dining” by the determined Axelrod, who persuaded him to throw himself into FD research. Like so many others who end up devoting themselves to rare diseases, Kaufmann was quickly hooked. FD was like nothing he'd seen before, and the untilled tract of medicine captured his imagination. He recruited 50 of Axelrod's patients—by far the largest FD cohort in a research study—for a battery of tests to better define the disease. Kaufmann presented his findings this week at a neurology meeting in Toronto, Canada. Among other things, Kaufmann says he discovered that FD patients in crisis produce large amounts of dopamine—something also seen in Parkinson's patients given levodopa, a drug that is converted to the neurotransmitter dopamine. Although extra dopamine counters the effects of Parkinson's, it also causes constant vomiting; Parkinson's patients get a drug called carbidopa to block the production of dopamine from levodopa outside the brain. Carbidopa is never given alone, but Kaufmann wondered if it should be in those with FD. The center received almost$200,000 from FDA to find out, and it will begin testing the drug this month.

Deciding where to focus funding for a disease like FD is difficult. Does it make sense to invest in better managing it in young adults, as Kaufmann wants to do with carbidopa, or to focus on a cure in younger patients, who are healthier but are so few? “You can't pick,” says Axelrod. “It's like saying which child do you love more,” the 3-year-old or the 23-year-old?

Brenner at the Dysautonomia Foundation agrees. “As long as there's one new baby born, you want to find a therapy that will stop the disease in its tracks,” he says. But already, with so few FD births, the Dysautonomia Foundation is finding it tougher and tougher to sustain interest in FD. “This is a real challenge,” Brenner says. “Raising money is easier when you have more patients, and when those patients are very sick, young children. It's hard to resist giving money to help children survive.” Furthermore, as science has advanced, the research needs—drug development and animal work—have grown more expensive.

The foundation has tried to be more creative about its fundraisers, arranging bowlathons and cycling tours, and it is still raising between $1 million and$2 million a year.

Although winning grants remains an uphill battle, diseases like FD are receiving more government support, even as they grow rarer. If peer reviewers back a proposal, “we do fund them,” says Danilo Tagle, the program director in neurogenetics at the National Institute of Neurological Disorders and Stroke in Bethesda, Maryland. His portfolio includes Tay-Sachs, for which the institute last summer awarded $3.5 million over 4 years for a new genetherapy effort. “Knowledge of this disease will contribute to any number of disorders,” says Tagle, explaining why the agency would pour so much money into a disease whose caseload has dropped so much and which is preventable with genetic testing. Those working in rare diseases are frustrated by talk of their disappearance. That's because, they say, diseases like FD are unlikely to vanish, and studying them holds much value. It “tells us a lot about development and basic biology,” says Susan Slaugenhaupt of Massachusetts General Hospital in Boston, who found the FD gene and has since shifted toward developing new treatments. One challenge, she says, is balancing an exclusive focus on the disease with the “big picture”: the general implications often needed to justify a grant. The FD team is finding some intriguing details about the disease. For example, says Norcliffe-Kaufmann, they are learning which emotions produce a physiologic response. Excitement often sends the autonomic nervous system, which controls blood pressure and heart rate, into overdrive in an FD patient, but embarrassment doesn't have much effect. Why is that, and what might it tell us about broader connections between blood pressure and emotion? No ones knows. ## Sustaining curiosity It's the morning after the first night of Passover, raining hard, and Axelrod's office is quiet. (“When you work in a Jewish genetic disease, patients don't come in today,” she says.) One wall is decorated with dozens of photos of her patients—in karate uniforms, at their bar mitzvahs, with children of their own. She knows them all. Is she worried that others will perceive a now-preventable disease like FD, with only 350 surviving patients worldwide who are slowly dying, as undeserving of money and attention? “Absolutely,” she says. Kaufmann, munching on leftovers from Axelrod's seder the night before, explains his efforts to make FD sound “sexy” to other researchers, in hopes of drumming up attention, by describing the underlying abnormalities in their nervous system as opposed to their symptoms. “When you come out with interesting things, you get other bright minds interested,” he says. An Australian researcher visited in early April, carting in equipment to study afferent nerve fibers—the nerve cells that convey signals about pain—in FD patients. For FD families accustomed to leisurely chats with Axelrod, the shift to more intensive research in which they are asked to participate has been somewhat disconcerting, says Kaufmann. But, say Axelrod, Kaufmann, and others, now is the time to probe this disease as never before—and before its numbers dwindle even further. 11. # Screening Disease Away 1. Jennifer Couzin-Frankel When it comes to genetic diseases, deciding who to screen can be difficult. Many early programs targeted specific populations whose members are more likely to carry the disease mutations, whereas in other groups, physicians don't think to offer carrier testing or consider it cost-effective. For familial dysautonomia (FD), the goal of screening potential carriers has always been clear: prevent new cases. “I can't imagine an FD parent saying there's a good reason” to have more babies born with the disease, says Amelia Peck, a curator at the Metropolitan Museum of Art in New York City whose 18-year-old daughter, Alice Altshuler, has FD. When it comes to genetic diseases, deciding who to screen can be difficult. Many early programs targeted specific populations whose members are more likely to carry the disease mutations. In the early 1980s, for example, with broad community support, the government of Cyprus launched an unusual mandatory screening program for the blood disease beta-thalassemia, which was so prevalent that 1 in 150 babies were being born with it on the island. With screening, the disease virtually disappeared. The Jewish community began aggressive enzyme testing for Tay-Sachs in the early 1970s, and that disease has almost vanished among Jews. But Tay-Sachs shows up in non-Jews as well. While about 1 in 27 Ashkenazis are carriers, about 1 in 250 in the general population are. Most new cases of Tay-Sachs are now in non-Jews, whose physicians don't think to offer them carrier testing or consider it cost-effective. In the United States, where carrier screening is more available and more accepted than in virtually any other country, “none of us is a pure-breed, if you will,” says Wendy Chung, who directs the clinical genetics program at Columbia University. “We're literally a melting pot, [and] it's difficult to know what you should screen for” in any given individual. “I think everyone” should be screened for FD, says David Brenner. “Not everyone is so in tune with their ancestry” that they're aware they may be at risk. Brenner is executive director of the Dysautonomia Foundation in New York City, which has partnered with the California company Counsyl to help it spread the word about carrier screening. It's holding events that bring together dozens of adults who can take Counsyl's carrier test for more than 100 genetic diseases; the company picks up the balance if insurance doesn't cover the full cost. But as carrier testing expands, its goals are changing. In the past, they were unequivocal: cut down on new cases of a disease. But these days, there is a “reframing,” says Wylie Burke, a geneticist and bioethicist at the University of Washington, Seattle. Screening is presented vaguely as “providing options,” she says, or offering reassurance to noncarriers. Partly, she believes, that's due to discomfort with aborting affected pregnancies. Screening before pregnancy—the approach Counsyl advocates—rarely happens. Implanting embryos unaffected by disease genes is expensive and “available only to a narrow stripe of people,” Burke notes. Another reason for ambivalence about screening is that many diseases for which it is available are considered less severe. Canada came out against universal screening for cystic fibrosis (CF) carriers in 2002, rejecting the U.S. policy. In part, that's because its health care system would have had to pay, says Anne-Marie Laberge, a medical geneticist at CHU Sainte-Justine in Montreal, Canada, but also because patients with CF now experience an “improved quality of life.” That said, a study of 23 couples in California who learned through prenatal testing that their fetus had CF found that 20 terminated the pregnancy. 12. # Besting Johnny Appleseed 1. Sam Kean With a few tricks, and a lot of patience, fruit geneticists are undoing the work of an American legend. KEARNEYSVILLE, WEST VIRGINIA—Ask how many fruit trees he's responsible for, and Michael Glenn just laughs. “I have no idea,” he says. Glenn oversees some 120 hectares as director of the Appalachian Fruit Research Station here, and seemingly every road leads to a new orchard. Glenn tramps through one rolling 6-hectare plot on a bright day in March, pruning season. Half the branches of some trees lie discarded. After thinking for a moment, Glenn guesses that 315,000 trees live on the station's acreage in the eastern handlebar of West Virginia. To fit them in, the station plants row after row of ash-brown trees, two meters tall and about as far apart, in military formations. The regularity is deceptive. Even though all these trees are the same species, Malus x domestica, the apple, there's no end to the variety of shapes and postures they assume. Glenn, trim, white-haired, points out that some trees grow vertically like elms, while some droop like willows. Some have branches with elbows and right angles, still others lack a central trunk and sprout stalks like bamboo. And that's only part of the variety he'll see when their fruit arrives in late April. Cross two adult fruit trees—a wild variety resistant to disease, say, and a domesticated one with sweet fruit—and there's almost no telling what you'll get. As slower-breeding plants, apples are not far removed from their wild ancestors, so they have had fewer chances to shed unwanted genes. And apple trees cannot reproduce with close relatives because special proteins recognize their own or similar pollen and choke off reproduction. Growers get consistent varieties only through clonal propagation, and today 11 cloned varieties make up 90% of the apples sold in the United States. This leaves apples vulnerable to diseases and environmental stress. To “update” a popular variety to withstand those traumas, a breeder must cross it with apples with quite different genes, which can dilute or scatter its good qualities. This genetic roulette makes for interesting walks through orchards but frustrates scientists who want to develop consistent but hearty apples, plums, and pears. “Stringent, ugly, bitter, tiny fruit, squishy, doesn't store well—anything you can think of that will be bad in a fruit—it happens,” says Cameron Peace, an apple and cherry geneticist at Washington State University, Pullman. Traditional breeding, part of what Glenn calls “cultural practices,” requires crossing two lines of apples, each with one or a few good traits. The result: anonymous brown pips. Once, the only way to sort the duds from sweet and hearty varieties was to plant them all, an expensive and laborious job. And because first crosses rarely meet supermarket standards, breeders improve them by recrossing the best fruit of each generation with other varieties, up to five times. A faster approach would be tweaking apple DNA directly with the tools of molecular genetics. But until recently, geneticists, their skills honed on Arabidopsis and other quick-breeding flora, avoided fruit-tree research like a blight. Of the 11,000 U.S. field tests on plants with transgenic genes between 1987 and 2004, just 1% focused on fruit trees. That's partly because of the slow pace. Whereas vegetables like corn might produce two harvests each summer, apple trees need eons—around 5 years—to produce their first fruit, most of which will be disregarded as ugly, bitter, or squishy. Given the odds, 315,000 trees can look tiny. But everything in apple breeding is about to change. An Italian team plans to publish the decoded apple genome this summer, and scientists at places like Kearneysville, which is run by the U.S. Department of Agriculture (USDA), are starting to single out complex genetic markers for taste and heartiness. In some cases the scientists even plan, by inserting genes from other species, to eliminate the barren juvenile stage and push fruit trees to mature rapidly, greatly reducing generation times. Glenn came of age when someone might spend decades breeding the Johnagold or Fuji. No more. Expectations are changing, and as Glenn says, “The orchards of the future will be driven more by genetics than cultural practices.” ## Legends in their times In the early 1800s, a nomad named John Chapman began wandering through Pennsylvania, Ohio, and beyond, a burlap gunnysack of seeds (as tradition has it) over his shoulder, to spread the apple to the American frontier. That most apple trees he planted gave squishy or crabby fruit didn't make Johnny Appleseed's gifts any less welcome for farmers and hunters eager to make liquors like cider and applejack. But not all were stringent, and many “dessert” apples with colorful names like Irish Peach, Maiden Blush, and Sops of Wine thrived in America. Unfortunately, Chapman, no geneticist, had drawn on a narrow stock of European apples—itself a narrow selection of wild apples, which are native to Kazakhstan. Other U.S. stocks, spread by pioneers and missionaries, had the same shortcomings, and grafting clones further tapered the line. (Every single Red Delicious traces back to one farm, Jesse Hiatt's, near Peru, Iowa, for example.) Meanwhile, USDA's efforts to breed heartier varieties have proved inefficient and slow. The foundations for modern apple research were laid in the 1990s. Fittingly, it all started with another trek to the frontier, by another legend among apple breeders. Philip Forsline had already made a name for himself in the 1980s when Cornell University decided to bulldoze its renowned groves of apple trees. Forsline, an apple curator for USDA's Agricultural Research Service, oversaw the transfer of every variety from Cornell in Ithaca, New York, to his USDA research station 70 kilometers away in Geneva, New York, where buds were meticulously grafted onto rootstock. Even those holdings, however, were genetically narrow, so USDA drew up ambitious collection trips to China and Kazakhstan. Forsline made seven trips to Central Asia in the 1990s, collecting apples from coastlands and inland steppes, from veritable deserts and dense forests where 90% of trees sprouted apples. He saw groves where bears smashed branches to knock apples loose, and among the thousands of shapes he saw a few 8-centimeter beauties “that looked like they could be at the supermarket,” he marvels. In all Forsline collected 949 varieties of Malus sieversii trees, forerunner to the domesticated apple. Back in New York state, Forsline recreated the Kazakh and Chinese forests (with humans pruning instead of bears) by planting 1600 seedlings. And as he loves to joke, the work is finally bearing fruit. Over the past dozen years, he and his successor at Geneva, Gennaro Fazio, have monitored which apples could weather cold snaps or dry spells, and which handled “The Gauntlet”—a pestilential greenhouse crawling with pathogens that kills three-quarters or more of all prisoners. After these tests, Forsline and Fazio have identified apples that can withstand nearly any natural evil. The next trick will be identifying the key genes and getting them into the 11 apple varieties Americans covet. ## Double trouble Traditional breeders face two barriers to making better apples, plums, and pears: the staggering inefficiencies and the tedious wait between generations. Genetic work has the potential to eliminate both problems. As for the inefficiencies, “you can use molecular tools … to screen a large population of seedlings” for genetic markers associated with a desirable trait, explains Gayle Volk, a geneticist at USDA's National Center for Genetic Resources Preservation in Fort Collins, Colorado. If scientists screen for multiple traits, only 10 or so of 1000 seeds may have the right combination, she says, but scientists can focus on those few. Peace discovered a great example of the potential savings through work on ethylene, a natural hormone that causes fruit to ripen. Breeders want low ethylene levels so that fruit doesn't turn mushy in trucks on the way to stores. Peace has discovered two gene markers for fruit that produce 90% less ethylene, and with his tests, breeders can discard three of every four seeds and possibly save 60% on maintaining groves. Ultimately, Peace wants to find markers for taste, the most desirable and elusive trait that fruit breeders pursue. Texture and crispness are largely fixed by genes, while all-important sweetness depends heavily on environmental factors, and scientists don't know the details. But thanks to collaborations like USDA's$14.4 million RosBREED project, Peace thinks geneticists can start finding robust correlations for taste within about 2 years.

Still, even the best screening won't solve the second problem, that fruit trees mature so slowly. But scientists at Kearneysville, in collaboration with scientists at a few universities, may have a shortcut. In the next 6 months or so, Kearneysville geneticist Jay Norelli will begin a project to introduce two alleles for resistance to fire blight, a common apple plague, into dessert apples. Using traditional methods, it would take 20-some years to fix this trait into a supermarket-quality apple. But by introducing a “fast-flowering” gene from a poplar tree, Norelli believes he can cut the generation time down to roughly a year.

The process works like this. First, scientists introduce the fast-flowering gene into the chromosomes of a dessert apple, with traditional genetic engineering tools (such as a bacterium loaded with the fast gene). Scientists then cross this altered apple with a complementary variety that might not taste good but is resistant to disease. After this cross, scientists will, as usual, get many dud seeds. But they can screen their DNA and find varieties likely to taste good, mature quickly, and withstand diseases. They discard the rest. Scientists then cross the best of the new generation with another tasty (but not fast-flowering) apple. And once again, they select the best offspring. With each subsequent cross, they become more like dessert apples, except disease-resistant.

Norelli is confident the poplar transgene shortcut can work because colleagues at the research station, led by horticulturist Ralph Scorza, have used it to create fast-flowering plums, a close relative of the apple.

Control plum trees in the Kearneysville greenhouse, which lack the accelerating gene, have sturdy, woody trunks and stand a good meter tall after 12 months. The controls are also barren—and will be for several years until they reach fruit-bearing age. The experimental, “FasTrack” trees look softer and greener, and they slouch. But that's partly because their branches are bowed down from the weight of plums. Sixty more plum-poplar trees are growing outdoors on a few of Kearneysville's 120 hectares. And like Norelli, Scorza will soon begin introducing new traits into the plums, at speeds that would have seemed miraculous 50 years ago.

To determine how sweet the FasTrack plums are, Scorza's team will chemically test their sugar concentration this summer. But no one will know how they taste for some time. Including a poplar gene makes the trees genetically modified (GM) food, and scientists would need government permission to sample them. What's more, no one knows whether poplar genes in fruit will do something unwanted, like shortening the life of the tree.

But the Kearneysville geneticists have a neat trick to circumvent these concerns. Only a fraction of the offspring in each generation contain the fast-flowering gene. Early in the breeding process, scientists discard the trees that lack it. (They search for the gene by doing PCR on a tissue sample.) But once they have fixed a new trait in the fruit, they select against fast-flowering in the final generation. This selection involves no genetic engineering: They simply screen the trees (again, usually with PCR), and toss out the ones with the poplar gene. The leftover trees, which mature normally, are no different than if Scorza's team bred them the traditional way. And as long as any new genes came from wild or semiwild fruit, the trees are, almost magically, no longer GM.

As for potential controversies, Scorza argues that the FasTrack system combines “the latest methods of modern biology with a breeding tradition as old as agriculture.” And he thinks it will become valuable with global climate change. “Fifteen, 20 years is no longer good enough” to deliver new fruit varieties to a hungry world, he says.

Still, it's telling that not even FasTrack breeders can eat their fruit—a far cry from the American frontier farmer. And opponents of GM food seem unlikely to accept a “non-GM” label for such varieties. Bill Freese, a science policy analyst at the Center for Food Safety in Washington, D.C., has not studied the new FasTrack program but said, “the genetic engineering process is very disruptive” and often changes surrounding DNA. “Our experience with USDA is that they tend to downplay risks with genetic engineering.”

## What's next

For the next few years, apple, plum, and peach trees will dominate the grounds of places like Kearneysville. But scientists elsewhere are developing ways to maintain the genetic diversity of fruit with as few trees as possible. In Colorado, Volk has studied cryogenic preservation of dormant buds in liquid nitrogen, and the results show promise for reducing the number of trees that must be kept in dirt. Nitrogen tanks cost $1.50 per year per bud to maintain compared with$50 to \$75 per orchard tree. And the germ plasm shows no ill effects.

Even at Kearneysville, breeders spend more and more hours indoors in their labs and fewer in the groves. In fact, Glenn says he's become an anomaly—someone who even prunes on occasion. But most traditional breeders, Glenn included, are eager to eliminate all the tedium and heartache of traditional methods. “Personally, I am nostalgic for the so-called better days, but I think this is the natural progress of science,” he says. What's more, in the past 5 years, “the molecular biologists are coming back to the field-oriented scientists to collaborate with them on projects in the field.”

So although the informal days of Johnny Appleseed are gone forever, fruit breeders still have a place, and scientists are trembling with excitement at the possibilities. Forsline estimates that his trips to Asia have doubled the known stock of apple genes in the world. Johnny Appleseed may have made the American apple in the 1800s, but as Forsline has written of modern fruit work, “All of this—and forthcoming findings—may one day put the impact of [USDA research] on a par with that of John Chapman's legendary work.”

13. Engineering

# Nanogenerators Tap Waste Energy To Power Ultrasmall Electronics

1. Robert F. Service

Tiny devices that convert movements into electricity won't power cities. But they may soon be efficient enough to power arrays of invisible sensors and hand-held electronics.

In the corner of a conference center on the main campus of Microsoft in Redmond, Washington, engineers have built a small four-room apartment. Called MS Home, it serves as both a testing ground and a showcase for how the future home may look and, well, behave. In Microsoft's vision, that home will be run by a computer system that turns on lights, controls the heat, and manages the appliances. An array of invisible sensors would do everything from tracking your movements (in order to know when to turn the lights on in the next room) to monitoring whether your plants need water.

Uses of sensor networks have been talked about for years. One stumbling block has been figuring out how to power the devices. Sure, each one could be plied with batteries or wired to the grid. But that is expensive and requires periodic maintenance, which often upends such proposals. Now, however, the rise of a new technology to scavenge power from vibrations and other ambient sources may finally usher this vision of the future into the present.

Power scavengers have actually been around for some time. Companies, for example, already make larger scale devices that harness vibrations to monitor the structural health of buildings and bridges. But over the past few years, researchers have been progressively shrinking these scavengers to nanoscale dimensions in an effort to power everything from minuscule sensors inside the body to arrays of self-powered environmental sensors to monitor things such as air quality and stream flows. This miniaturization push has been aided by the steady progress of microelectronics technology, which now turns out sensors and computing devices small enough and frugal enough with their energy needs that many can be powered with just nanowatts to microwatts of power.

Today, the field “has now reached a critical mass and momentum,” says Zhong Lin Wang, a physicist at the Georgia Institute of Technology (Georgia Tech) in Atlanta. “I am confident that with the way things are progressing, this will one day soon impact our daily lives.”

Although several technologies are competing to power such devices, most nanogenerators are made from piezoelectric materials that convert mechanical motion into electricity. Piezoelectric materials, such as crystals of the ceramic lead zirconate titanate (PZT), are made of subunits that separate electrical charges. Mechanical strain, such as bending a thin piezoelectric wire, changes this electric polarization of the material and causes positive and negative charges to migrate to opposite faces of the material, creating an electric voltage that can be used to do work. The effect can also be reversed: Applying a voltage across a piezoelectric crystal causes it to move. This effect—first discovered in 1880—is behind decades of technology; sonar detectors, loudspeakers, autofocusing cameras, atomic force microscopes, and many other gadgets.

Today the most widely used piezoelectric material is PZT, as it is the most efficient material at converting mechanical strain to electricity. But PZT has its drawbacks. For starters, it is brittle and breaks easily. It also contains lead, a toxic metal, which makes it a poor choice for powering medical sensors in the body.

Now, researchers may have found a way around PZT's shortcomings. In the 10 February issue of Nano Letters, researchers led by Michael McAlpine, a chemist at Princeton University, reported the creation of a flexible PZT nanogenerator encapsulated inside a biocompatible plastic. McAlpine notes that whereas large crystals of PZT are brittle, ultrathin ribbons of the material can bend and flex without breaking. So McAlpine's team grew a thin layer of PZT atop a crystal of magnesium oxide (MgO) and then used a lithographic patterning technique, akin to that used to pattern microchips, to pattern the PZT into an array of long ribbons. They then dissolved the MgO substrate, leaving the ribbons behind, and pressed a rubbery plastic known as PDMS on top, transferring the PZT nanoribbons to the plastic (see bottom figure). Several characterization studies showed that the transferred PZT nanoribbons retained their same piezoelectric properties, and they were roughly four times as efficient at transferring mechanical strain to electricity as were competing nanogenerators.

Still, flexible PZT nanoribbons have a way to go before they are ready to power real devices, McAlpine says. Among the steps still needed is to refine the PZT nanowire growth techniques. McAlpine says it should be possible to improve the power output of the devices 10-fold. Also, he says, scaling the technique up to make larger arrays would help to power more types of devices.

If efforts to make PZT nanogenerators more flexible and biocompatible don't succeed, alternatives are moving in to pick up the slack. Wang and his colleagues at Georgia Tech, for example, have pushed nanogenerators made from zinc oxide (ZnO) nanowires considerably further than their PZT cousins. In 2006, Wang and his student Jinhui Song reported in Science that they grew arrays of vertical ZnO nanowires that when bent to the side created a small electric voltage (Science, 14 April 2006, p. 242). In the years since, Wang's team has developed successive iterations of their ZnO nanogenerators in an effort to increase the power output and robustness.

Last month, they raised the bar to the highest point yet. In a paper posted online in Nature Nanotechnology on 28 March, Wang and colleagues reported making two new nanogenerators. One produced the highest voltage of any nanogenerator to date; the other produced a lower voltage but was rigged up to power either a pH sensor or an ultraviolet detector without need for any outside energy. Both nanogenerators were made by growing arrays of long, thin zinc oxide nanowires. In the version wired to the sensors, these nanowire collections resemble a bed of nails with thin electrodes placed on the top and bottom. When the researchers then squeezed their device—thereby bending the nanowires—it produced 0.24 volts, with enough current to run their sensors. “That's pretty cool,” says McAlpine, who credits Wang for pioneering several nanogenerator concepts.

One of those was Wang's higher voltage nanogenerator. Pushing the output is important, Wang says, because most devices today need more than one-quarter of a volt to run. Standard AA battery–powered devices, for example, require up to 1.5 volts to operate—well beyond what most nanogenerators can generate.

To make a higher voltage device, Wang and his colleagues needed to find a way to make the voltage output of individual nanowire devices add up. To do so they needed to orient the crystallographic axis of each ZnO nanowire in the same direction so that when force was applied to them all collectively, the polarity of charges on each wire would be aligned, producing a higher output voltage. Wang's team patterned an array of parallel chromium wires atop a substrate. They then grew thousands of ZnO nanowires laterally between these wires, like rungs in a ladder, under conditions that ensured they all grew with the same crystallographic orientation. Finally, they soldered the ZnO nanowires to the chromium by depositing gold at the connection points (see figure). The scheme worked. When they flexed their array, it generated 1.26 volts. That's not quite the 1.5 volts of a AA battery, but in the months since their paper was submitted, Wang says his team has upped that output to 2.4 volts. “This enables us to operate true technology,” Wang says.

The Georgia Tech group isn't the only one closing in on that goal. At the University of California, Berkeley, another nanogenerator group, headed by mechanical engineer Liwei Lin, is making nanogenerators out of long polymer fibers that one day may be woven into cloth. “This technology could eventually lead to wearable ‘smart clothes’ that can power hand-held electronics through ordinary body movements,” Lin says.

For their nanogenerators, Lin and his colleagues start with a polymer called polyvinylidene fluoride (PVDF) that can be processed to separate electrical charges. Other groups have previously made PVDF generators from thin films of the polymer. But PVDF films are typically inefficient, converting only 1% to 2% of kinetic energy to electricity. Lin and his colleagues also reported in the 10 February issue of Nano Letters that when they used a technique called electrospinning to spin PVDF into threadlike fibers as little as 500 nanometers across, the resulting fibers converted 10 times as much kinetic energy to electricity as the thin-film PVDF devices did.

Although Lin and his colleagues are still trying to understand exactly why that is, Lin says part of the explanation probably has to do with the electrospinning technique. The method draws out the polymer fibers in the presence of a large electric field, which seems to orient individual polymer molecules better than the filmmaking techniques do (see figure, left). And once the fibers are formed and solidify, this arrangement is locked in place. The output is high enough, Lin says, that calculations suggest that 1000 or so fiber generators incorporated into the cloth of a shirt would capture enough energy from a person's movements to charge a cell phone or an iPod. Although Lin says he hasn't yet formed a company to commercialize his power-suit material, he's already taking visits from venture capitalists looking to do just that.

If nanogenerators of any sort succeed, could they possibly be scaled up to generate large amounts of power? After all, most of the handwringing about energy these days is about how to generate terawatts, rather than microwatts, of carbon-free power. Lin, Wang, and McAlpine agree that for now that doesn't seem likely. Nanogenerators simply produce too little power to change our civilization. For now, they'll be working on the small scale, which might still be enough to change our lives.