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  1. 1. books Beyond Star Trek: From Alien Invasions to the End of Time—Lawrence M. Krauss. In this follow-up to his successful book The Physics of Star Trek, Krauss uses the television show The X Files and the movie Independence Day, among others, to illustrate cosmological conundrums. For example, aliens like those in Independence Day would probably have arrived on Earth only to find it devastated by weather brought about by the gravitational effects of their spaceships. The basics of quantum mechanics, advances in warp-drive systems, and the possibility of extraterrestrial life are also deftly considered. Originally published in hardcover in 1997. HarpPL, 1998, 190 p., paperback, $12.00. Doubt and Certainty: The Celebrated Academy Debates on Science, Mysticism, Reality in General on the Knowable and Unknowable, with Particular Forays Into Such Esoteric Matters as the Mind Fluid, the Behavior of the Stock Market, and the Disposition of a Quantum Mechanical Sphinx, to Name a Few—Tony Rothman and George Sudarshan. The subtitle certainly conveys the text's gist, but readers may be interested to know that these witty authors are physicists. Their Western and Eastern philosophies flavor these dialogues concerning issues in modern physics and the clashing or meshing of New Age ideals. In what they describe as a "cross between Plato's Republic and the 1001 Nights," Rothman and Sudarshan reinvent Plato's academy, melding their thoughts with those of their ancestors and contemporaries. Each section is prefaced by background on its subject and is concluded with a puzzle or exercise. Perseus, 1998, 320 p., hardcover, $25.00. The Handy Geography Answer Book—Matthew T. Rosenberg. The Handy Physics Answer Book—P. Erik Gundersen. Fans of The Handy Science Answer Book and its progeny should find these two offshoots to be equally appealing methods of nourishing one's curiosity about the physical world. Not just a book about maps, the geography volume answers queries about climate, exploration, disasters, and individual continents, such as: What are the four climatic regions of the Andes, and what was the Ottoman Empire? A concluding section lists vital statistics for 192 countries. The physics book explores more than 800 fascinating aspects of physics, including sound, waves, fluids, thermodynamics, magnetism, and electricity. Readers discover the difference between center of mass and center of gravity, how a compass is made, and how objects maintain
  2. 2. an orbit around Earth. Both books Visible Ink, 1999, 462 p./415 p., color plates/b&w illus., paperback, $19.95. Magnitude 8: Earthquakes and Life Along the San Andreas Fault—Philip L. Fradkin. For nearly 20 years, Fradkin has lived within shouting distance of the point on the San Andreas Fault that moved 20 feet in 1906. His proximity to one of the most turbulent faults in the United States informs his discussion of the natural elements of earthquakes and the impact of this phenomenon on the cultural and daily lives of people who reside near faults. Fradkin blends these elements into his consideration of the outcome of a future magnitude 8 quake, the difficulty in predicting quakes, and the rationale of fault-dwellers. H Holt & Co, 1998, 336 p., hardcover, $27.50. The Pattern on the Stone: The Simple Ideas That Make Computers Work—Daniel Hillis. Using analogies befitting a child, Hillis tells how computers compute. He begins by imparting Boolean logic through a demonstration of a machine that plays tic-tac-toe. Then, he describes a universal construction set in terms of the shortcomings of Lego blocks. He goes on to aptly describe Turing machines, algorithms, heuristics, and encryption. Hillis gift is his ability to convey the logical processes of computers that begin with switches and circuitry and escalate to self-organizing learning ability relevant to parallel computing systems. Basic, 1998, 164 p., illus., hardcover, $21.00. Sutton Hoo: Burial Ground of Kings?—Martin Carver. On three separate occasions during the past 60 years, archaeologists unearthed mounds exhibiting unusual burial tactics in southeastern England. Dating to 600 a.d., these graves of medieval English aristocrats were swollen with not only human remains but also a bounty of artifacts. Some individuals were buried in their boats, others were entomed with their horses, art, and precious metals. Carver attended the last of these digs, and he recounts the content of the sites and the theories about them offered thus far. Penn, 1998, 195 p., color plates/b&w photos, hardcover, $29.95. Straight Talk About Psychiatric Medications for Kids—Timothy E. Wilens. A specialist in pediatric and adult psychopharmacology at Massachusetts General Hospital surveys the gamut of childhood mental, emotional, and behavioral conditions treated with medication. First explaining the conditions and their hallmark symptoms, Wilens then presents treatment options and facts about associated medications. Early chapters answer
  3. 3. questions about the medicating process and its short-term and long-term effects on children. A guide to psychotropic medications concludes the book. Guilford, 1999, 279 p., paperback, $14.95. Letters Warmer than when? The article "Sizzling June fires up greenhouse debate" (SN: 7/25/98, p. 52) contained two errors. First, while the 1990s have been the hottest decade since people began systematic temperature measurements in the mid-1800s, it is not the hottest decade on record. Even proponents of the theory of human-caused global warming recognize data indicating Earth has been hotter than it is now many times—most recently around 600 years ago, before the advent of the most recent "little ice age." The current warming trend began as Earth came out of the little ice age—an important fact that is all too often overlooked in the global warming debate. Second, the Kyoto Protocol is not stalled in any Senate committee, since the Clinton administration has yet to sign it or submit it to the Senate for ratification. The administration recognizes that the treaty has several problems and has vowed not to submit it to the Senate until they are addressed. H. Sterling Burnett National Center for Policy Analysis Dallas, Texas There is little debate about the statement that the 1990s is the warmest decade on record for global temperatures. Reliable records of global temperatures reach back only into the 19th century. For earlier times, researchers try to gauge temperature trends from a much spottier data set, which can hardly be considered a global record. More important is the question of whether Earth is now warmer than it was earlier in this millennium. There is evidence that parts of Europe were warm during the so-called Medieval Warm Period, particularly in the 11th and 12th centuries, but it is far from clear whether this was a global phenomenon and whether temperatures during this period were higher or lower than today's. Some parts of the globe did not show any warming back then, whereas other regions warmed up at different times than did Europe. The Intergovernmental Panel on Climate Change in its 1995 report said that "it is not yet possible to say whether, on a hemispheric scale, temperatures declined from the 1112th to the 1617th centuries. Nor, therefore, is it possible to conclude that global temperatures
  4. 4. in the Medieval Warm Period were comparable to the warm decades of the late 20th century." The IPCC later said that data from studies of alpine glaciers "suggest that in at least alpine areas, global 20th century temperatures may be warmer than any century since 1000 AD, and perhaps as warm as during any extended period (or several centuries) in the past 10,000 years." With regard to the Kyoto Protocol, you are correct that the administration has not yet submitted it to the Senate for ratification. —R. Monastersky No smoking gun Your news report "Exposure to smoke yields fetal mutations" (SN: 10/3/98, p. 213) omitted mentioning the relevant epidemiology. A Medline search yielded four studies that do not indicate that maternal smoking/passive smoking increases cancer risk among infants. These studies directly contradict the statement by NCI's Sholom Wacholder that epidemiological findings link prebirth exposure to carcinogens with childhood leukemia. I don't know what studies Wacholder refers to, but they certainly have nothing to do with maternal smoking. Steven Milloy Potomac, Md. Diabetic Pregnancy Risk Starts Early Diabetic women who become pregnant typically seek a doctor's advice during the first trimester. They are told to take care of themselves and to be especially careful to keep their blood sugar under control. Not only are they up to four times more likely than nondiabetic women to miscarry, but their babies face three times the normal risk of congenital defects. A study in mice now suggests that, in some cases, such counseling may come too late. The research indicates that apoptosis—natural cell suicide—often goes awry in a diabetic mouse embryo and wipes out healthy cells. What's more, this damage can occur soon after fertilization, researchers report in the December Nature Medicine. If the findings translate to humans, those prenatal consultations should become preconception visits, says study coauthor Kelle H. Moley, a reproductive endocrinologist at Washington University in St. Louis.
  5. 5. Apoptosis is a necessary cellular housekeeping process. When cells are no longer needed, become infected, or have damaged DNA, the suicide process dismantles the nuclear material and parcels out DNA fragments to nearby cells for disposal. Earlier research identified a protein called Bax as a key player in this cascade of events. In people with high blood sugar, such as those with diabetes who don't control their diet or who fail to take insulin, a surfeit of glucose boosts Bax production. Too much Bax induces some cells to kill themselves hastily. Moley and her colleagues suspected that high Bax concentrations might link diabetes to high rates of miscarriage and birth defects. To find out, the researchers mated male mice with three sets of females: 15 nondiabetic mice, 18 diabetic mice not receiving insulin, and 14 diabetic mice given insulin injections just before and after fertilization. The team extracted embryos from the female mice 48 to 96 hours after fertilization and found that Bax concentrations in the embryos from insulin-treated females weren't markedly different from those taken from healthy females. However, embryos from the untreated diabetic mice—exposed to an abundance of glucose in the mother's blood—had Bax concentrations nearly eight times as high, Moley says. To directly assess DNA damage, the researchers used three more sets of pregnant mice. DNA fragmentation in the embryos of untreated diabetic mice was more than six times as prevalent as in embryos of the healthy control mice and nine times as high as in embryos from insulin-treated diabetic mice. Significant cell death in the embryonic stage may abort a pregnancy—resulting in a miscarriage—while less damage may cause deformities, Moley suggests. The birth defects arising from pregnancies in diabetic women include heart damage, limb deformities, and neural tube defects leading to brain damage. The new study "is interesting," says David R. Hadden, an endocrinologist at Royal Victoria Hospital in Belfast, Northern Ireland. "They are making a very reasonable case, a good case." Still, the apoptosis explanation doesn't explain why some diabetic women with high blood sugar go on to have healthy babies, he says. Also, other research indicates that high glucose concentrations later in pregnancy seem to have deleterious effects, he adds. Fifty years ago in Europe, roughly one in three diabetic pregnancies "ended in disaster of some form," Hadden says. Today, that risk has fallen, indicating that prenatal glucose monitoring reduces the number of developmental problems. Still, 1 in 15 pregnancies in
  6. 6. diabetic women results in some type of congenital defect as compared with 1 in 40 among other women. Since research on human embryos is rare, monkey tests could be the next phase of study. "I think that would really nail down whether [the Bax findings] are a reflection of a human . . . phenomenon," Moley says. —N. Seppa Poor winter homes delay bird nesting A migratory bird that gets stuck with second-rate winter accomodations will achieve only lackluster breeding success the next summer, hundreds or even thousands of miles away, a new study suggests. "Making that link before has been impossible to do," says Peter P. Marra of the Smithsonian Migratory Bird Center in Washington, D.C. He and his colleagues established the connection by using a technique that's novel among ornithologists: deducing where a bird has been by the carbon isotopes in its tissue. Isotopes are forms of atoms with different numbers of neutrons. In the Dec. 4 Science, the researchers report that American redstarts that reach their New Hampshire summer breeding ground early—a big factor in nesting success—have isotope ratios typical of moist, food-rich winter habitats. Birds that arrive late, however, show ratios typical of poor, dry habitats. "Things we're seeing in the breeding grounds are caused by events the previous winter," Marra explains. Monitoring redstarts wintering in Jamaica, the researchers found that dominant males and the tougher females claim forest territories with abundant insects for food. An underclass of smaller, weaker redstarts gets pushed into scrub, which has fewer insects. The researchers found that birds in prime winter territories increased or maintained their weight, but the birds in the slums lost up to 11 percent of their body mass. Come spring, redstarts in the poor habitat took longer to pack on fat for the flight north, leaving some 10 days later than birds in the forest. The researchers could not track those particular birds north—a problem with many such studies. So Marra and his colleagues observed redstarts summering in central New Hampshire. Late-arriving males tended to be high in carbon-13, like the birds in the inferior winter habitats. There, birds ate insects that feed on dry-region plants, which typically build up extra C-13.
  7. 7. Trevor D. Price of the University of California, San Diego welcomes the report as the first evidence tying bad winters and bad summers in a way he and other researchers had suspected. "We've finally got some facts," he says. Scott K. Robinson of the University of Illinois at Urbana-Champaign points out that the study "certainly indicates there isn't enough good habitat" for wintering redstarts. He predicts the results will bolster claims that problems in the tropics contribute strongly to declines of migratory birds. Some scientists still think breeding-ground problems are more important. However, Robinson says, "I think the jury is still out." —S. Milius A female redstart from poor habitat may be late to her breeding grounds. Titanic wreckage still tells a riveting tale Eighty-six years after the RMS Titanic scraped against an iceberg and sank to the bottom of the Atlantic Ocean, researchers are still trying to unravel the mystery of what happened on that fateful night. The iceberg sliced several long slits, each no more than an inch wide, into the side of the ship. Yet the supposedly unsinkable vessel went down after no more than 3 hours. Now, a panel of naval engineers and scientists has concluded that the Titanic owed its rapid demise in large part to the failure of the rivets that fastened its hull together. According to a metallurgical analysis of samples retrieved from the wreckage this summer, the inconsistent quality of the wrought iron rivets weakened them, allowing the ship's steel panels to rip apart at the seams. Tim Foecke of the National Institute of Standards and Technology (NIST) in Gaithersburg, Md., presented results of the analysis this week in Boston at a meeting of the Materials Research Society. The panel's conclusion contradicts conventional wisdom, which holds that in the icy ocean water, the ship's steel hull turned exceptionally brittle and cracked apart. In 1991, a team of Canadian researchers tested a steel plate fragment from the ship and found that it was indeed brittle—not only when cold but even at room temperature. "We believe that brittle steel didn't have much to do with the sinking of the Titanic," Foecke says. "[We are] willing to declare the brittle steel theory dead." The Canadian researchers aren't convinced, though. "I would say—barring a miracle— the rivets have absolutely nothing to do with the sinking of the Titanic," says James
  8. 8. Matthews, an engineer and materials specialist at the Defence Research Establishment- Atlantic in Halifax, Nova Scotia. In 1996, the Marine Forensics Panel of the Society of Naval Architects and Marine Engineers began investigating the Titanic disaster. Panel chair William A. Garzke Jr., a naval architect at Gibbs & Cox in Arlington, Va., suspected that the rivets played an important role. Foecke, a panel member, then analyzed two rivets retrieved during a 1996 expedition to the wreck. He found that the rivets contained three times the expected amount of silicate slag, an impurity that strengthens the metal at concentrations of 2 to 3 percent but tends to weaken it at higher concentrations. Moreover, the slag ordinarily forms long fibers that run along the length of the rivets, reinforcing them. At the ends of the rivets, however, Foecke found the fibers turned to a horizontal orientation. Aligned that way, the layers of iron and slag easily peel apart. Last August, another expedition brought back more rivets for testing. Foecke found slag problems in 14 out of 30 samples. The additional data, Foecke says, confirm the rivet theory, first published in a NIST report issued in February. Matthews counters, "A lot of things draw interpretations, but they are not indicative of performance." He adds that the huge forces suffered by the ship when it snapped in two and hit the ocean bottom could have mangled the rivets. To bolster their respective theories, both Foecke and Matthews cite the RMS Olympic, a ship almost identical to the Titanic that was hit by a British warship in 1911. Foecke says that rivets popped out as far as 15 feet away from the point of impact. Matthews, on the other hand, focuses on the cracks, characteristic of brittle steel fracture, that propagated through the hull. The steel in both ships, and in ships built today, is of a poor grade, Matthews says. "There are no riveted ships anymore, yet 40 to 50 a year are lost," he reports. "Ships are sinking now for the same reason," he says—brittle fracture. The panel now plans to explore a third ship of Titanic's design, the HMHS Britannic, which rests beneath the Aegean Sea. With more rivet samples, the researchers can get a better statistical analysis of the material, he explains. "What sank the Titanic?" Foecke asks. "It hit an iceberg." The question is how it might have stayed afloat longer, giving time for help to arrive. Instead, more than 1,500 people perished, memorialized by the riveted steel hull that lies 12,000 feet beneath the waves. —C. Wu
  9. 9. Cross-section of a rivet from the Titanic. Gulf War syndrome may signal mental ills A mysterious and controversial illness said to afflict many veterans of the 1991 Persian Gulf War may often stem from mood and anxiety disorders rather than wartime exposure to infectious agents or toxins, a new study finds. On closer examination, diagnoses of Gulf War syndrome are often replaced by findings of depression, stress reactions, and related disturbances, reports a team led by internist Michael J. Roy of the Uniformed Services University of the Health Sciences in Bethesda, Md. "Many patients with [Gulf War syndrome] may in fact have treatable mood or anxiety disorders rather than mystery illnesses," Roy and his coworkers contend in the November/ December Psychosomatic Medicine. Their study, however, does not exclude the possibility that some Gulf War veterans suffer from an illness sparked by exposure to toxic substances. Symptoms linked with Gulf War syndrome include fatigue, headaches, sleep disorders, and memory loss. There are no clear guidelines for diagnosing this condition, although veterans need an illness diagnosis to qualify for government medical benefits (SN: 10/15/94, p. 252). Roy's group reviewed data from comprehensive medical examinations of 21,579 Persian Gulf veterans who had complained of health problems. Of that number, 17 percent exhibited one or more symptoms that can be related to Gulf War syndrome, which include evidence of infection; another 25 percent displayed signs of Gulf War syndrome and also of a separate health problem. The 2,306 veterans who had the most pronounced symptoms of Gulf War syndrome received further exams by internists, psychiatrists, and infectious disease specialists. These close evaluations yielded large drops in the proportion of diagnosed symptoms that the clinicians attributed to Gulf War syndrome. The physicians assigned just 18 percent of all diagnosed symptoms to the syndrome in these follow-up exams, compared with 30 percent in the initial assessments of all veterans with any signs of Gulf War syndrome. After these intensive evaluations—particularly those conducted at Walter Reed Army Medical Center in Washington, D.C., which convenes weekly meetings of physicians and
  10. 10. mental health workers to discuss diagnoses—the physicians often noted the presence of mood disorders or post-traumatic stress disorder. Symptoms of Gulf War syndrome may often arise as part of mood and anxiety disturbances, the scientists conclude. These mental disorders are often accompanied by the exact same problems—fatigue, headaches, sleep disturbances, and memory loss. The new study raises concerns about the inappropriate labeling of psychiatric ailments such as Gulf War syndrome, comment psychiatrist Allen J. Frances and psychologist Jean C. Beckham, both of Duke University Medical Center in Durham, N.C., in an accompanying editorial. Long-term investigations, however, will be required to address whether some Gulf War veterans indeed suffer from a distinct illness caused by toxic exposure, they say. —B. Bower Turtle genes upset reptilian family tree Paleontologists have long viewed turtles as evolutionary slowpokes, the sole survivors of an ancient group that later gave rise to other reptiles, birds, and mammals. A new genetic analysis, however, dramatically redraws the evolutionary tree of vertebrates and challenges conventional wisdom on turtle origins. "The slow-moving turtles that everyone thinks are slow in terms of evolution turn out to be fast evolvers," says Axel Meyer of the University of Konstanz in Germany, who collaborated in the study with Rafael Zardoya of the National Museum of Natural Sciences in Madrid. Turtles have always stood apart from lizards, snakes, crocodiles, and other reptiles because of their skulls. Most reptiles, together with birds, have two holes on each side of their skull, to the rear of their eyes. Paleontologists label these animals diapsids. Turtles lack any such holes and so are the only living anapsids, a group that includes fossils of the most primitive vertebrates capable of living entirely on land. Mammals are termed synapsids because they evolved from animals with one skull opening behind each eye. According to the standard evolutionary story, turtles retain some characteristics of the ancient anapsids. As such, biologists have regarded them as an example of the stock from which reptiles, birds, and mammals later evolved. Zardoya and Meyer explored this hypothesis by comparing the sequences of two mitochondrial genes from turtles to those of iguanas, tuataras, alligators, chickens, and mammals. Turtles fell squarely within the modern diapsids rather than in their expected
  11. 11. position on a branch outside the group, the scientists report in the Nov. 24 Proceedings of the National Academy of Sciences. Their results lend support to a 1996 analysis of reptile fossils, which also suggested that turtles evolved from diapsids, says Olivier C. Rieppel of the Field Museum of Natural History in Chicago. The two studies do not agree in their details, though. Rieppel and a colleague found that turtles were closest to snakes and lizards, whereas Zardoya and Meyer place turtles nearest to alligators and birds. Both cases suggest that turtles evolved from diapsids and then lost the characteristic skull holes. If so, turtles would not make a good model for early land-dwelling vertebrates. Critics counter, however, that both studies have major flaws. The new gene analysis, for example, included only a few types of animals. "If you sample only a limited number, you tend to get very, very wrong [evolutionary] trees," says Michael S.Y. Lee of Monash University in Melbourne, Australia. —R. Monastersky Turtles: An evolutionary enigma. Newer pennies pose a special toddler risk Toddlers have a habit of mouthing anything within reach, including coins. Last year alone, some 21,000 youngsters ended up in emergency rooms throughout the United States after ingesting these candy-shaped disks—mostly pennies. New evidence indicates that swallowing pennies minted after 1981 poses an especially dangerous threat to children and pets. Apart from the obvious choking hazard, the pennies can trigger stomach ulcers and erode into circular blades of tissue-ripping zinc, a physician reported this week in Chicago at the annual meeting of the Radiological Society of North America. Pediatric radiologist Sara M. O'Hara stumbled upon the problem in March 1997, when parents brought a 2 1/2-year-old boy into the Duke University Medical Center in Durham, N.C. Having watched in horror as their child ate a penny and nearly choked, they wanted to know what to do next. Once O'Hara X-rayed the boy and confirmed that the penny was in his stomach, the emergency room staff advised the parents just to wait for the penny to pass in the stool. But 4 days later, the boy was unwilling to eat, had a persistent stomach ache, and was vomiting blood. When O'Hara X-rayed the boy again, she saw a perforated, "moth-eaten disc" with irregular edges that looked "like something had been nibbling on it." Suspecting
  12. 12. it was a piece from some toy, she had another doctor remove it with a tool inserted down the child's throat. To her shock, what emerged was the penny. She says, "You could just make out the date, 1989, on what was left." "We had always thought pennies were innocuous visitors [to a child's gastrointestinal tract]," O'Hara explains. However, after 4 days in a child's stomach, this penny had lost one-quarter of its weight, developed dangerously ragged edges, and induced an ulcer in the stomach lining. Though most pennies will pass through a child safely, O'Hara has since encountered a second eroding penny. Pennies were once 95 percent copper and relatively inert. In 1982, however, the U.S. Mint began stamping pennies out of zinc coated with a thin veneer of copper. O'Hara suspects that through normal wear and tear, this copper skin can crack, allowing the stomach's hydrochloric acid to dissolve some of the zinc into a toxic, ulcerating soup. She notes that other U.S. coins, made mostly of nickel, pose no similar risk. —J. Raloff A 1989 penny after 4 days in a child's stomach. Preemie diets linked to IQ What a premature infant eats in the first month of life can have lasting intellectual impact —at least in boys—a new study finds. In the early 1980s, researchers at the Medical Research Council (MRC) in London randomly assigned more than 400 preterm babies born in Norwich and Sheffield, England, to receive either a standard infant formula or one that MRC had designed to meet a preemie's unusually high nutritional demands. At that time, special preemie formulas were just being developed. The special feeding lasted until an infant reached 4.4 lb or left the hospital, so most babies ingested the formula for only 4 weeks. In the Nov. 28 British Medical Journal, Alan Lucas and his colleagues at MRC report IQ scores for the two groups of formula-fed children, tested when they were about 8 years old. While girls from the two groups performed about equally, boys from the preemie- formula group scored an average of 12 points higher on verbal tests than boys who had received standard formula. Animal data have shown that males exhibit a heightened vulnerablity to effects of neonatal malnutrition on learning and behavior, Lucas' team says.
  13. 13. Cerebral palsy also was much less common among infants getting the MRC-designed formula. Today, most preemies are fed such a special formula. —J. Raloff Very Large Telescope: New infrared camera struts its stuff These heavenly pictures show off the capability of a sensitive infrared camera, installed Nov. 14 on the first of what will eventually be a quartet of 8.2-meter telescopes on Cerro Paranal mountain in Chile. The first of four instruments, collectively known as the Very Large Telescope, began operation in May. The last is scheduled to be completed in 2001. The telescopes will be able to work independently and as one large instrument. The image on the left homes in on the galaxy cluster CL2244-02, a few billion light- years from Earth. In this near-infrared and visible-light composite, the central, blue-green arc represents a more distant galaxy, whose light has been bent by the gravity of the massive cluster. The red arc (arrow) was detected only in the infrared and probably indicates bent light from an even more distant galaxy. The other image, a composite of three near-infrared pictures, shows the Milky Way star- forming region RCW38, some 5,000 light-years from Earth. In visible light, these young stars are hidden from view by the clouds of gas and dust in which they were born. The European Southern Observatory released the images Nov. 26. —R. Cowen Scientists harvest antibodies from plants People may never look at a field of corn quite the same way again. Several research groups and biotech firms have genetically engineered corn and other plants to manufacture valuable human proteins called monoclonal antibodies. The scientists hope to cheaply mass-produce antibodies that can treat cancers, stem the spread of infectious diseases, act as contraceptives, and even stop tooth decay. Strengthening that prospect, two recent reports indicate that antibodies synthesized by plants function normally in people and animals. "Twenty years ago, monoclonal antibodies were supposed to be the magic bullets. We think now is the time they're going to be those magic bullets," says Kevin J. Whaley of Johns Hopkins University in Baltimore, Md., an author of one of the studies. To combat infectious organisms, the human immune system makes a wide range of antibodies, each one a protein that binds to a specific molecular target. About 2 decades
  14. 14. ago, researchers learned how to transfer immune genes into microbes and animal cells, allowing them to make limited amounts of a single desired antibody. Scientists envisioned many uses for these monoclonal antibodies, such as homing in on cancer cells. Yet the promise of monoclonal antibodies faded over the years. When scientists first used mice to make monoclonal antibodies, for example, the human body rejected the molecules. With further genetic engineering, immunologists have of late created more humanized antibodies in mice, but the animals still can't synthesize adequate amounts. Monoclonal antibodies, therefore, can cost hundreds of dollars per microgram. In search of more prolific methods, several companies have genetically engineered cows and goats to secrete antibodies into their milk. While that approach should lower costs, there is concern that it may be difficult to separate the antibodies from any bacteria or viruses in the milk. "If we're going to begin using antibodies as either therapeutics or preventatives, we're going to need massive amounts. From a cost-effectiveness standpoint, and safety of production, plants look like the superior opportunity," says Charles J. Arntzen of Cornell University. Scientists calculate that plant-made antibodies will cost less than $10 a gram. Moreover, plants don't have many pathogens that infect people, says Mich B. Hein of EPIcyte Pharmaceuticals in San Diego. When plants make antibodies within their cells, however, they decorate them with sugar molecules—a process called glycosylation—in a manner different from that of human cells. That had raised concerns that these "plantibodies" wouldn't work as effectively as normal ones or that a mammalian immune system would perceive them as foreign. In the December Nature Biotechnology, Whaley and his colleagues report that when an antibody made in soy plants was applied to the vaginas of mice, it prevented infection by the genital herpes virus. Earlier this year, in the May Nature Medicine, Julian K-C. Ma of Guy's Hospital in London and his colleagues described the first use of a plantibody in people. Made in tobacco and applied to the teeth of volunteers, it prevented one of the bacterial infections that leads to tooth decay. Whaley and Hein are now working to make corn produce the antiherpes plantibodies, as well as antibodies that prevent sperm from reaching an egg. The antibodies could lace gels or other substances applied topically. Whaley argues that plants may be the only way
  15. 15. to produce antibodies inexpensively enough that they can be employed worldwide, even in developing countries. "The rest of the issues are not scientific. They're economic," agrees Hein. "We have to demonstrate the cost-effectiveness of this method." —J. Travis Objective Visions Historians track the rise and times of scientific objectivity By BRUCE BOWER In an influential 1749 atlas of the human skeleton and muscles, Dutch anatomist Bernhard Albinus describes his meticulous methods for bringing a particular specimen to the printed page. Albinus carefully cleans, reassembles, and props up a complete male skeleton; he checks the position of each bone in comparison with observations of an extremely skinny man hired to stand naked next to the skeleton; he calculates the exact spot at which an artist must sit to view the skeleton's proportions accurately; and he covers engraving plates with cross-hatched grids so that images can be drawn square-by- square and thus be reproduced more reliably. The modern reader of Albinus' work then gets a shock. After all that excruciating attention to detail, the eminent anatomist announces that his atlas portrays not a real skeleton, but an idealized version. Albinus has dictated alterations to the artist. The scrupulously assembled model is only a springboard for insights into a more "perfect" representation of the human skeleton, visible only to someone with Albinus' anatomical acumen. It seemed perfectly reasonable for 18th-century knowledge seekers to defer to the informed imaginations of acknowledged geniuses such as Albinus. Objectivity was not an issue. That term did not acquire its current cachet in science until the 19th century. Then, many scientists decided it was best to find ways to let nature speak for itself rather than through the mouths of designated geniuses, says science historian Peter L. Galison of Harvard University. Only recently, in historical terms, has science aspired to be based on impartial treatment of physical objects, as opposed to subjective impressions. Ever since science's embrace of objectivity, according to Galison and other historians, the conceptual ground beneath the idea has shifted enough to give pause to anyone who
  16. 16. views it as a fixed vantage point from which successive scientific generations gaze upon reality. Historical analyses conducted in the past decade conclude that scientists' working notions of objectivity and its usefulness have changed in significant and revealing ways. External reality has remained a constant focus of inquiry, the historians emphasize, but investigators frequently grapple with the daunting task of deciding which of its myriad features merits special attention. Enter objectivity. Historians view objective standards as a flexible framework for reasoning about the world and communicating with large networks of peers in a chosen field. Science's success and growth, combined with outside pressures to solve societal problems and to justify research funding, have helped shape and transform this framework. The historians' efforts to study objectivity have great significance for what are called the science wars. They revolve around clashing beliefs over what scientists can know about the world. Combatants in that intellectual slugfest tend either not to know about work on the history of objectivity or to view it with ambivalence, remarks Ian Hacking, a philosopher of science at the University of Toronto. Hacking is familiar both with the historical analyses and the ongoing bitter debate over the nature of science. On one side of the battle stand scholars, including sociologists and philosophers, who portray objective methods in science as products of a social consensus among practitioners based on their shared assumptions about the nature of reality. Objectivity then is a tool that scientists use to tell stories about how the world works and to boost their power and prestige, according to advocates of this perspective. Critics of this view respond that conventions of objectivity allow researchers to chip away at chunks of reality that, with perseverance, yield basic laws of nature. Cultural and personal philosophies may organize scientific approaches to a problem, but theories grounded in real-world evidence eventually yield culturefree knowledge, in this view. Science historians express frustration with what they see as a tendency of both sides in this battle to treat objectivity as something locked in place, an indentured servant either of personal and social interests or of external reality. "The great debate about the desirability of objectivity in science is highly confused," says Lorraine Daston, director of the Max Planck Institute for the History of Science in Berlin. "Objectivity has had and continues to have different meanings." Its modern
  17. 17. meanings include empirical reliability, procedural correctness, emotional detachment, and absolute truth, she notes. Adds Theodore M. Porter of the University of California, Los Angeles, "We need to examine more closely the historical development of objectivity without making the exercise an attack on science." A good place to begin untangling the roots of objectivity is the scientific atlases that proliferated from about 1830 to 1920, holds Galison. At that time, atlas makers embraced a form of objectivity in which cameras and a host of other machines were seen as stages on which nature could speak for itself without human prompting, he maintains. Atlases in this tradition of "mechanical objectivity" covered a vast array of phenomena—fossils, clouds, stars, elementary particles, bones, wounds, embryos, and plants, to name a few. Inspiration for the new wave of atlases derived partly from growing unease with the earlier scientific practice of Albinus and other supposedly inspired geniuses to fish out "true forms" from beneath nature's surface. For instance, turn-of-the-century paleontologists began to question their convention of drawing ideal versions of partial or misshapen fossils, which were then used as centerpieces for evolutionary theories. Around the same time, an increasing number of established scientific theories came under attack or were discarded. Investigators started to doubt whether they possessed a stable core of knowledge. Particularly stinging was the replacement of the Newtonian theory of light with the wave theory championed by French physicist Augustin Fresnel. Scientists of the 19th century rapidly adopted a new generation of devices that rendered images in an automatic fashion. For instance, the boxy contraption known as the camera obscura projected images of a specimen, such as a bone or a plant, onto a surface where a researcher could trace its form onto a piece of paper. Photography soon took over and further diminished human involvement in image-making. In a joint article published in the Fall 1992 Representations, Galison and Daston documented the rise of mechanical objectivity in scientific atlases. Researchers explicitly equated the mechanical registration of items in the natural world with a moral code of self-restraint, Galison and Daston hold. A blurry photograph of a star or ragged edges on a slide of tumor tissue were deemed preferable to tidy, idealized portraits.
  18. 18. A saintly struggle against the temptations of interpreting and improving what one observed was a kind of purifying ritual for scientists, readying them to receive natural truths, the two historians suggest. Astronomer Percival Lowell's effort at the start of the 20th century to establish the reality of canals on Mars starkly illustrates this point, according to Galison. Lowell took great care in sketching his initial telescopic discoveries. After observing more features of the Martian landscape, Lowell described in his journal how he refused to add these characteristics to earlier drawings because he wanted to ensure scientific objectivity and guard against unintentional "artistic delineations." Lowell also agreed with book editors to refrain from a judicious retouching of his blurry, gray photographs of the Red Planet, which would have made Mars' canals visible in published reproductions. Such embellishments would invite claims that "the results were from the brain of the retoucher," Lowell's editors wrote to him in 1905. So, readers of his book were left to squint at a hazy version of the scientist's hard-won images. Daston and Galison each emphasize different implications for science in the rise of mechanical objectivity. In the Winter 1998 Daedalus, Daston contends that this brand of objectivity accompanied broader cultural changes in Europe that polarized artists and scientists. Her article's title describes what she sees as the result: "Fear and Loathing of the Imagination in Science." In the 18th century, imagination was viewed as essential to philosophy and science as well as to the arts, Daston says. Moreover, facts were assumed to arise out of particular observations or experiments and were subject to later revisions. Romantic poets, writers, and artists of the 19th century claimed imagination as their inner muse, calling it an unexplainable creative impulse residing within the individual. Scientists, on the other hand, broadened their pursuit of objectivity beyond its basic mechanical form, in Daston's opinion. Researchers began to standardize their instruments, clarify basic concepts, and write in an impersonal style so that their peers in other countries and even in future centuries could understand them. Enlightenment-influenced scholars thus came to regard facts no longer as malleable observations but as unbreakable nuggets of reality. Imagination represented a dangerous, wild force that substituted personal fantasies for a sober, objective grasp of nature.
  19. 19. Scientists then and now acknowledge the presence of imagination in their work, particularly in devising ground-breaking theories and experiments, Daston notes. She suspects, however, that mainstream researchers experience a complex mix of admiration, envy, and disdain for the relatively few creative pioneers in their midst. Galison, however, says that by around 1920, mechanical objectivity gave way to an emphasis on a kind of trained imagination in medical and natural sciences. Many atlas makers in these fields chose images that, in their opinion, brought into relief crucial elements that would help the observant reader learn how to interpret such displays with an expert eye, he suggests in Picturing Science, Producing Art (1998, Caroline A. Jones and P.L. Galison, eds., Routledge). In this approach, subjective impressions got a reprieve. However, they were assumed to work in favor of all experienced practitioners and researchers rather than simply a few geniuses. A 1941 atlas of electroencephalograph, or brain-wave, readings provides an example of how informed judgment replaced mechanical objectivity, Galison asserts. The authors wrote that they used their many years of experience to select EEG waveforms that would best help novices notice key patterns and train themselves to reach accurate diagnoses at a glance, such as distinguishing between the wave output of a person with epilepsy and one without epilepsy. Nonetheless, scientists of all stripes still find much of value in a facet of mechanical objectivity that emphasizes the impartial application of standard mathematical methods, says Porter. Quantitative rigor proves most alluring to troubled scientific communities, which are buffeted by internal divisions and outside criticisms, he argues. Objective standards attempt to heal the distrust among researchers who are largely strangers to one another by making their specialized knowledge public and impersonal. In contrast, and perhaps somewhat surprisingly, disciplines that enjoy a more secure status operate largely on the basis of informal, shared conventions rather than rigidly applied objective methods. Porter explored several examples of this pattern in his book Trust In Numbers (1995, Princeton University Press). For instance, mathematically precise cost-benefit analyses were developed in the early 20th century by the U.S. Army Corps of Engineers. In the face of intense political pressure, the corps had been plagued by "utter disunity and savage
  20. 20. infighting," Porter says. At the same time, powerful congressmen opposed the corps' efforts to plan and carry out major public works projects. Analysis of congressional testimony, internal corps documents, and other sources indicates that strict cost-benefit formulas expressed in mathematically objective terms, such as those in the 1936 Flood Control Act, were developed by the corps to unite warring engineers and to overcome legislators' concerns about its competence to carry out complex tasks. Yet, at the same time, the French government's engineering corps successfully resolved controversies over the location and costs of various public works without conducting a single cost-benefit analysis. Unlike their U.S. counterparts, the French engineers reached consensus on thorny issues through informal discussions informed by their past professional experiences. French politicians left the engineers alone, regarding them as elite and eminently trustworthy products of the national educational system. Members of France's engineering corps showed no interest in cost-benefit rules until after World War II, when U.S. influence expanded in Europe, Porter contends. Today, the small community of experimental high-energy physicists operates much in the tradition of France's prewar engineers, in his view. These scientists—a select few who survive a long process of formal training and research apprenticeships—have access to only a few particle accelerators and constantly adjust or even completely rebuild their own detectors for new experiments. Independent replication of experimental results proves extremely difficult when the equipment constantly changes from one researcher to another. Instead, influential physicists assess the skill and trustworthiness of experimenters and reach agreement as to whether a particular set of findings merits acceptance. In contrast, experimental psychology, which faces stark internal divisions and considerable political pressures, clings to rigid statistical formulas of objectivity (SN: 6/7/97, p. 356), the UCLA researcher holds. Historical work like Porter's challenges the widespread tendency to treat objectivity as "a given" that never changes, comments Hacking. "Scientists employ techniques and ways of thinking which are powerful and effective, but which are often hard to articulate," Porter says. "In science, as in political and administrative affairs, objectivity has more to do with the exclusion of personal judgment and the struggle against subjectivity than with truth to nature." n
  21. 21. In 1849, just before the flowering of scientific objectivity, botanist Joseph Hooker directed the drawing of this plant, based on observations of several blossoms. He chose to present what he saw as Rhododendron argentum's characteristic features. Star motions yield four more planets The hunt for planets outside our solar system continues to show results. The latest findings include a nearby, sunlike star that may have two companions: a planet and a heavier object, known as a brown dwarf. Studies also suggest that three other nearby stars have closely orbiting planets, bringing to 16 the number of extrasolar planets that astronomers have indirectly detected around sunlike stars. As recently as August, only 10 such planets had been identified (SN: 8/8/98, p. 88). The main search strategy has stayed the same since the first extrasolar planet was discovered in 1992. By tracking the back-and-forth motion of nearby stars toward and away from Earth, astronomers infer the gravitational tug of planets too faint to be detected directly. This technique favors the detection of massive, closely orbiting planets, since these bodies induce the largest wobbles in their parent stars. Researchers have identified two planets among a sample of 82 stars they had begun monitoring recently at Lick Observatory on Mt. Hamilton in California. The team had already been studying 107 stars at Lick for several years. One of the newly found planets, which orbits the sunlike star HD195019, is at least 3.51 times as massive as Jupiter and whips around the star in just 18.27 days. The other planet found at Lick Observatory circles the sunlike star HD217107 once every 7.12 days and is at least 1.27 times as massive as Jupiter. Geoffrey W. Marcy of San Francisco State University and the University of California, Berkeley and his colleagues, including R. Paul Butler of the Anglo-Australian Observatory in Epping, Australia, will report both Lick findings in the January 1999 Publications of the Astronomical Society of the Pacific. A third discovery, which Marcy announced Dec. 2, during a talk at Marymount College in Palos Verdes, Calif., concerns a star whose motion was tracked at the W.M. Keck Observatory atop Hawaii's Mauna Kea. The wobble of the star HD168443 suggests that it has a planet, which is at least 4.96 times as massive as Jupiter, in a highly elongated orbit.
  22. 22. The tug of a single object can't fully explain the star's motion, however. Marcy proposes that the star has another companion—either a tiny star or a brown dwarf, an object heavier than a planet but too lightweight to shine continuously as stars do. The fourth find comes from a Swiss team working at the European Southern Observatory's La Silla Observatory in La Serena, Chile. Using a new telescope and spectrograph devoted to tracking stellar wobbles, the team found evidence of a planet circling Gliese 86, a dwarf star with a mass 0.79 times that of the sun. About 35 light-years from Earth, this is the second-closest star known to harbor a planet. Gliese 86 has another distinction: It possesses an unseen stellar partner. The separation between the two stars is probably more than 100 times larger than the distance between the newly discovered planet and the star it orbits, the Swiss team reports. The planet circles the star once every 15.83 days and is at least 4.9 times as massive as Jupiter. It is separated from its parent by just over one-tenth the distance between the sun and Earth. Didier Queloz of the Geneva Observatory and NASA's Jet Propulsion Laboratory in Pasadena, Calif., and his colleagues announced the finding on Nov. 24. —R.C. The new Leonard Euler Telescope at La Silla Observatory. Fill 'Er Up . . . With Veggie Oil Vegetable oils are moving from the kitchen table to the car engine By CORINNA WU Oil from plants—such as these sunflowers growing in a field near Davis, Calif.—can serve as an environmentally friendly substitute for petroleumbased products. Asked to name a striking image from the 1970s, some might think of President Nixon making his resignation speech, a news photo from the Vietnam War, or even a young John Travolta striking a pose.
  23. 23. Others might recall the long lines of cars at gas stations during the oil embargo. From October 1973 to March 1974, Arab nations banned oil exports to the United States in retaliation for U.S. support of Israel during the Arab-Israeli War. Gasoline became a rare and precious commodity. Those lean days made it all too clear how heavily the United States had come to depend on imported petroleum and how easily its supply could be cut off. The energy crisis of the 1970s, followed by high oil prices in the early 1980s, sparked widespread interest in alternative energy sources. Today, gasoline is again plentiful and cheap, and the long lines at gas stations are a fading memory. Research into alternatives, however, continues. Some geologists predict that petroleum production will peak within 2 decades, then diminish, triggering a sharp rise in oil prices (SN: 10/31/98, p. 278). Hoping to develop technologies that could lessen U.S. dependence on imported oil, some scientists are looking to a homegrown solution, literally. They are developing diesel fuels and lubricants based on vegetable oils—the same vegetable oils that people drizzle on salads and use to cook french fries. Oils from soybeans, corn, canola, and sunflowers all have the potential to move from the kitchen to the garage, researchers say. In some applications, fuels and lubricants made from vegetable oils actually perform better and pollute less than their petroleum counterparts. Their big drawback, however, is that they're two to three times more expensive. For that reason, researchers are adapting vegetable oil for those fuel markets where its advantages might justify its cost. The idea of using vegetable-based products as fuel is not new. German engineer Rudolf Diesel reportedly employed peanut oil to power one of his engines at the Paris Exposition of 1900. In the late 1970s, petroleum makers stretched limited fuel supplies by mixing gasoline with ethanol from fermented corn. This formed a cleaner-burning concoction known as gasohol (SN: 10/29/77, p. 280) that is still available. Gasohol burns more completely than petroleum, producing less carbon monoxide and hydrocarbons. To some researchers, vegetable oils seem like a natural choice for an alternative fuel since the United States grows an abundance of agricultural crops. In Europe, strict
  24. 24. environmental regulations have made vegetable oilbased products an even more attractive choice, since they present less of a problem if accidentally spilled. Seventy to 80 percent of a vegetable oil biodegrades to small organic molecules, carbon dioxide, and water in standardized tests compared with only 20 to 40 percent of a conventional lubricant, says André L. Boehman of the Pennsylvania State University in State College. In a junkyard, a car leaking canola oil won't contaminate the soil as badly as one leaking conventional gasoline or oil. A boat that inadvertently dumps soybean-based diesel fuel into a lake won't foul the water as much as one releasing regular fuel. Farmers also look to the oil research as a way to increase the market for their crops, says Lowell Norland, director of community and business services for the Ag-Based Industrial Lubricants Research Program at the University of Northern Iowa in Waverly. Toward this goal, scientists in the oil research group at the Department of Agriculture's National Center for Agricultural Utilization Research (NCAUR) in Peoria, Ill., are studying the properties of biodiesel, a type of fuel derived from vegetable oil. It may someday serve as an alternative to the diesel fuel used in many trucks and boats. Ordinary diesel fuel is a mixture of hydrocarbon molecules of differing lengths and structures. These molecules contain no oxygen atoms. Some hydrocarbons consist of long, straight carbon chains; others branch like a tree or form rings. They may have double-bonded carbons that cause the chains to bend. The characteristics of the hydrocarbons affect how they burn. Vegetable oils, on the other hand, are mixtures of fatty acids—molecules that contain carbon, hydrogen, and oxygen atoms. The fatty acids may be saturated, monounsaturated, or polyunsaturated, meaning they contain zero, one, or multiple double bonds between carbons, respectively. The greater the number of double bonds, the more easily the compound reacts with oxygen from the air and goes bad, as kitchen fats and oils do after months on the shelf. Saturated fats, such as those in lard, have another disadvantage as a fuel or lubricant. They turn solid at low temperatures, while mono- and polyunsaturated oils remain liquid. Researchers have their eye on polyunsaturated soybean oil, in particular, because many of its properties, such as viscosity and combustibility, are similar to those of petroleum- based oils. To produce biodiesel, chemists treat a vegetable oil in a process called transesterification. This turns the oil into methyl ester compounds, which burn more cleanly than diesel fuel and leave fewer engine deposits than untreated vegetable oil.
  25. 25. When burned in an engine, biodiesel emits smaller amounts of pollutants, including particulates, volatile organic compounds, carbon dioxide, and polyaromatic hydrocarbons, than regular diesel fuel does, says Gerhard Knothe, a scientist at NCAUR. Notable exceptions are the nitrogen oxides, major contributors to smog, which biodiesel generates more of than does petroleum diesel. On the other hand, biodiesel contains no sulfur, unlike regular diesel, so acid-rain- producing sulfur oxides aren't a problem (SN: 8/27/94, p. 134). "You can smell the difference," Knothe observes. "The fumes from biodiesel are less obnoxious." An advantage of biodiesel over other alternatives to petroleum is that it works in existing diesel engines. Other clean-burning fuels such as natural gas have combustion properties so different from those of diesel fuel that they can't be used in conventional engines. Natural gas must also be stored differently. "The fuel [itself] may be cheaper, but the engine and infrastructure changes are so expensive, they outweigh that advantage," says Knothe. In terms of performance, however, biodiesel isn't yet up to par. Because of its unsaturated fatty compounds, vegetable oil reacts with oxygen more easily than diesel does, and so its properties can change. Biodiesel can also leave more gummy deposits in engines than regular diesel does. And just like cooking oil placed in the freezer, biodiesel thickens and forms solid crystals —mostly of saturated fats—at low temperatures, plugging fuel lines. At 0°C, components of biodiesel begin to crystallize. Lower the temperature a few degrees more, and the fuel no longer flows. "Here in the Midwest, we'd be in trouble," says Knothe. The fix is rather simple: The scientists can winterize the fuel by cooling it until the crystals form, then filtering them out. The resulting biodiesel can start an engine at 15°C, a temperature comparable to petroleum-based diesel. Some of the fats filtered out, such as methyl palmitate and methyl stearate, tend to have the best combustion properties, however. "It's a tradeoff," says Knothe. "You improve one property, but you have to be careful about the other." Biodiesel can be combined with conventional diesel fuels, says Knothe. Several companies manufacture a blend known as B20 because it contains 20 percent biodiesel and 80 percent regular diesel fuel.
  26. 26. Biodiesel improves the slipperiness, or lubricity, of diesel fuel. When sulfur is removed during refining of conventional diesel, the lubricity goes down. "If you add [biodiesel] in, you get the lubricity back," says Knothe. As an additive to a fuel tank, biodiesel could potentially reduce wear on moving engine parts. In a similar way, vegetable oil added to an engine's oil pan can do the duty of motor oil while polluting less. Boehman, Joseph M. Perez, and their colleagues at Penn State are studying an engine lubricant made from sunflowers genetically modified to produce oil with a high concentration of monounsaturated oleic acid. To test a formula made by Renewable Lubricants in Hartville, Ohio, they compared it with a 10W-30 petroleum-based oil. In the lab, Boehman explains, he puts lubricant in a small diesel engine, which he runs at a variety of temperatures and engine speeds. He passes the exhaust through a filter and collects particles of soot and other pollutants. The researchers see a reduction in particle emissions with the sunflower oil, although they want to confirm those results with additional tests, says Boehman. He presented some of the group's recent findings in August at a Boston meeting of the American Chemical Society. In regular engine operations, "most of the emissions come from the lubricant," he says. Oil vapors that don't get burned condense on the solid particles of soot that fly out through the exhaust pipe. Vegetable oil doesn't evaporate as easily as petroleum-based oil, so less finds its way out of the engine. Because oleic acid has only one double bond, it doesn't react with oxygen as readily as polyunsaturated oils do. Adding antioxidants to sunflower oil improves its stability, to resemble that of 10W-30 motor oil. As foods, monounsaturated oils such as olive and canola oil may have health benefits (SN: 11/21/98, p. 328). Therefore, many agricultural seed companies are genetically modifying plants to increase their proportion of monounsaturated oils, says Norland. "What seed companies are developing for human consumption is also very good for industrial lubricants." If vegetable oilbased fuels and lubricants are to compete with conventional ones, their price will have to drop considerably.
  27. 27. "Biodiesel will not be able to replace all conventional diesel," says Knothe. "If you took all the vegetable oil in the world and made biodiesel out of it, you'd only replace a few percent of the whole conventional diesel market. That's the reason why the National Biodiesel Board [a trade organization] is targeting niche markets." These markets would include urban bus fleets, mining equipment, and marine vessels. Mine and marine environments face particular threats from fuel spills. One factor that would reduce the price is an increase in supply spurred by changing patterns of consumption, Norland suggests. Soybean products, for example, are gaining recognition for their heart-healthy qualities (SN: 5/30/98, p. 348). "As soybean flour is used more and more, oil becomes a by-product," he notes. Legislative activity may drive the acceptance of vegetable oilbased fuels and lubricants, whatever their price. The omnibus spending bill recently passed by Congress recognizes B20 as an alternative fuel. The Clean Air Act of 1990 and the Energy Policy Act of 1992 also create markets for these products. In Germany's Black Forest region, environmental protection laws require farm machinery to use only biodegradable fuels and lubricants, thereby instituting "almost a requirement to use veggie oil," says Boehman. Several products based on canola oil are used in Europe. At the University of Northern Iowa, Lou Honary and his colleagues developed a vegetable oil replacement for hydraulic fluid used in heavy machinery such as forklifts and garbage trucks. An Iowa bill passed this year requires all state agencies to purchase as much of this fluid, called BioSOY, as allowed by their budgets and manufacturer warranties on equipment. Oil companies themselves don't see vegetable-based products as a threat, according to Honary. Instead, they have already jumped on the bandwagon. "I don't know of any petroleum company that doesn't have a green program running," he says. "They are all trying to find some way to promote the use of vegetable oils. They'd like to have this alternative for certain applications." In the end, researchers hope that vegetable oils will perform well enough to convince people to use them. Honary looks to the example of Sandia National Laboratories in Albuquerque, N.M. The facility tested BioSOY in 20 of its own vehicles from 1996 to 1997. This hydraulic fluid worked so well that Sandia decided to use it in all of its vehicles. n Legislative activity may drive the
  28. 28. acceptance of vegetable oilbased fuels and lubricants, whatever their price Iowa lawmakers are encouraging state agencies to use BioSOY, a hydraulic fluid made from soybean oil, in vehicles and heavy machinery. Biodiesel fuel made from processed soybean oil emits fewer pollutants when burned and is less harmful to the environment if accidentally spilled. Biology Geraniums intoxicate Japanese beetles Several bites of a garden-variety geranium, and a Japanese beetle falls to the ground in a stupor that lasts some 8 hours. It's hardly a great way to avoid predators or get on with beetle business, like reproduction. Yet researchers now find that the beetles never learn. They choose geraniums over perfectly good linden leaves and get paralyzed day after day. Researchers described the knockout effect on Japanese beetles in 1929, notes Daniel A. Potter. He and David W. Held, both of the University of Kentucky in Lexington, have studied beetle learning and the sad effects of geranium intoxication on family life. Their results will appear in an upcoming issue of the journal Entomologia Experimentalis et Applicata. In theory, insects with wide-ranging tastes are the most likely to learn to avoid noxious foods, according to the few studies that have tested this idea, Potter says. However, Japanese beetles eat nearly 300 U.S. plant species but don't avoid geraniums. The flower petals, especially from plants in full sunlight, seem the most narcotic, Potter reports. His most extensive tests were of red geraniums, but flowers of white, coral, and other colors also slammed the beetles. So did a water-soluble leaf extract. A geranium "is like candy to them," Potter says. Beetle pairs offered a choice picked geranium flowers so often that they laid just half as many eggs as pairs provided only with linden leaves. Intoxication is dangerous for the beetle, but is it fun? Potter won't speculate. —S.M. Ravens' memories can lead to thievery
  29. 29. Ravens not only remember where they hid their own food; there's evidence they remember—and steal—caches of other ravens. As far as Bernd Heinrich is aware, his raven studies at the University of Vermont in Burlington are the first to show that a bird's memory for caches extends to somebody else's hoard. Ravens don't just sniff out hidden meat, report Heinrich and John W. Pepper of the University of Michigan in Ann Arbor. When Heinrich, unseen by the birds, hid 40 caches in snow in a large, outdoor aviary, the ravens failed to find even one. Yet when nine ravens hid food at the same time and looked for it the next day, they found 58 out of 85 caches. Fifteen of these were thefts. The ravens appeared to search deliberately in specific spots, Heinrich says. He has also observed that a raven changes its hiding strategies, going farther to stash booty, if others are watching. Results appear in the November Animal Behaviour. —S.M. Diverse fungi underlie plant success There's a hidden side to plant diversity that people had better start paying attention to, warn two research teams. Their experiments demonstrate the major importance of soil fungi in shaping plant communities, say Marcel G.A. van der Heijden of the University of Basel in Switzerland, John N. Klironomos of the University of Guelph in Ontario, and their colleagues. Yet the possible loss of diversity in soil fungi has hardly been studied, they lament in the Nov. 5 Nature. Most soils have so-called arbuscular mycorrhizal fungi, which grip roots and boost nutrients for an estimated 80 percent of land plant species. A forest might have 30 of these fungal species, but crop fields typically have few, Klironomos says. The Swiss researchers grew greenhouse pots of 11 plants with different soil fungi. Plant growth varied depending on the fungus. "This was a surprise," Klironomos notes. Researchers had assumed that any of the fungi could partner with any plant. Outdoors, Klironomos' group seeded each of 70 tubs with the same combination of 15 plants but different fungi, from a lone species to a mix of 14. All the plants sprouted, but in some tubs, a few species took over. Plant communities were most diverse in tubs with eight or more fungal species. —S.M.
  30. 30. Behavior Schizophrenia: Consenting adults . . . Apathy, hallucinations, inappropriate emotions, and confused or paranoid thoughts rank among the central symptoms of schizophrenia. Nonetheless, a new study suggests that determined investigators can help people suffering from this disorder discern the pros and cons of participating in research. Scientists and clinicians have raised concerns about the ability of individuals with severe psychiatric conditions to grasp the risks and benefits of research projects they're asked to take part in. For example, up to one-half of hospitalized patients with schizophrenia and one-quarter of those with major depression exhibit markedly impaired judgment in interviews conducted shortly after their admission (SN: 1/7/95, p. 8). Schizophrenia sufferers, however, understand and remember much about proposed clinical trials after exposure to thorough procedures for gaining their "informed consent," contends a research team led by psychiatrist Donna A. Wirshing of the West Los Angeles Veterans Affairs Medical Center. The researchers recruited 49 psychiatric patients diagnosed with schizophrenia who were already participating in ongoing trials of several antipsychotic medications. An experimenter first read to each patient an informed-consent document concerning an upcoming randomized clinical trial. A researcher then administered a survey that Wirshing's team devised to gauge how well volunteers understood what they had heard. Surveys probed for knowledge about the study's procedures and goals, patients' available choices as participants, their physicians' responsibilities to the investigation, and potential ill effects of antipsychotic drugs that were to be given in the trial. Five patients answered all survey questions correctly on an initial test. For the rest, a researcher immediately explained any items that were answered incorrectly and administered the survey again. Another 26 patients correctly answered all questions on a second try, and 18 did so after three or more attempts. One week later, all the volunteers still answered most survey items correctly, the scientists report in the November American Journal of Psychiatry. This finding held even for patients displaying the most severe thought disturbances and hallucinations. In an accompanying editorial, psychiatrist Paul S. Appelbaum of the University of Massachusetts Medical School in Worcester remarks that other tactics to boost psychiatric patients' capacity to consent to research should also be explored. These include involving
  31. 31. family members in the teaching process and using instructional videotapes, he says. — B.B. . . . and memory lapses Schizophrenia is often marked by poor performance on memory tests, accompanied by diminished activity in frontal brain areas involved in reasoning. It's unclear, however, whether these mental lapses tap into a neural disturbance specific to the disorder or reflect the unwillingness of frequently apathetic schizophrenia sufferers to make the mental effort to remember. A study directed by neuroscientist Paul C. Fletcher of the Institute of Neurology in London lends support to the latter view. Twelve people with schizophrenia and seven adults with no psychiatric ailments underwent positron emission tomography (PET) scanning as they learned and recalled lists of 1 to 12 words. PET scans yield measures of blood-flow changes in the brain, an indirect sign of mental activity. In schizophrenia, frontal brain activity and memory performance dropped as tasks became more demanding, consistent with a lack of mental effort, Fletcher's group reports in the November Archives of General Psychiatry. In contrast, the researchers found, frontal activity rose in the mentally healthy adults as they successfully recalled more information on progressively more challenging tasks. —B.B. Biology From Los Angeles at the annual meeting of the Society for Neuroscience Voles are addicted to love It's said that love is a drug. In a rodent species, scientists may now have proof. They've collected evidence that love, or more accurately, the choice of a mate, stimulates the brain in the same way as do drugs such as cocaine and heroin. "This type of social attachment uses the same reward pathway," says Thomas R. Insel of Emory University in Atlanta. For many years, Insel has examined the brain chemistry behind the monogamy of one strain of voles (SN: 11/27/93, p. 360). When these rodents mate, their brains release chemicals that prompt the animals to form enduring partnerships. In females, it's a compound called oxytocin that drives the vole's attachment to a partner. In fact, injections of oxytocin into the brain of a female vole can duplicate the effects of mating and induce pair bonding. Drugs blocking oxytocin's action prevent females from pairing with males after mating.
  32. 32. Hoping to explain oxytocin's effects, Insel and his colleagues Brenden S. Gingrich and Carissa Cascio have studied the role of another brain chemical, the neurotransmitter dopamine. Recent research indicates that the addictive nature of many drugs, including nicotine, depends on dopamine. The drugs' pleasant sensations are stimulated by the neurotransmitter's release within a brain region called the nucleus accumbens (SN: 7/20/96, p. 38). Over time, the brain appears to become more and more dependent on this dopamine, causing people to crave the drugs. Insel's group has now found that this reward mechanism may drive the monogamy of voles as well. Brain injections of dopaminelike drugs induce female voles to prefer a single male, without mating, while dopamine-blocking agents inhibit the usual bonding that occurs after mating. The researchers also measured the natural production of the neurotransmitter within the brains of female voles as they mated. Within the nucleus accumbens of mating females, the scientists found dramatic dopamine increases, which lasted for several hours. Insel and his colleagues have discovered that brain cells in the nucleus accumbens sport the cell-surface proteins that oxytocin activates. Blocking these receptors made it less likely that female voles would pair after mating. From such evidence, the researchers hypothesize that mating induces oxytocin production, which in turn stimulates the release of dopamine. —J.T. The threat of a piece of pumpkin pie Some people with the eating disorder anorexia nervosa may have an actual fear of food, according to a new study. Alan J. Strohmayer of the North Shore University Hospital in Manhasset, N.Y., and his colleagues found that people with anorexia nervosa experienced a stress response, detected by activation of their sweat glands, when simply viewing photos of pizza, pasta, ice cream, and other foods. People with bulimia, who deliberately vomit after eating, didn't react in the same way. The researchers tested five women with anorexia nervosa and five with bulimia. On average, sweat gland activity in those with anorexia nervosa increased by 52 percent when they saw the images of a dozen different foods. Many psychologists argue that anorexia nervosa stems from a fear of gaining weight, which causes people to avoid eating and, in some cases, to starve themselves to death. A food phobia, says Strohmayer, hasn't been considered before. It's not surprising that people with bulimia don't share this phobia, since they don't refrain from eating, he adds.
  33. 33. Strohmayer notes that current psychological treatments for anorexia nervosa often prove unsuccessful. He suggests that people with the eating disorder might be treated with desensitization therapy. Patients would be gradually exposed to their phobia—food— more often. This approach has worked for people with fears of flying and spiders, for example. —J.T.