Optimism Is Key to Successful Aging

A resilient attitude may be the secret to successful aging, perhaps even trumping good physical health, finds a new study. Researchers surveyed 1,006 randomly selected adults in San Diego, Calif., between the ages of 50 and 99 (with a mean age of about 77) through a 25-minute phone interview, followed by a mail-in survey. In addition to evaluating the participants' physical health conditions, such as chronic disease and disability, the survey looked at more subjective factors like adults' social engagement and self-assessments of their overall health and degree of successful aging. The team found that older adults with low physical functioning but high resilience — the ability to bounce back from negative events or setbacks — had comparable self-ratings of their degree of successful aging to those of physically healthy people who were less resilient. Meanwhile, people who were less physically able but had no or low levels of depression reported self-ratings similar to those of physically healthy people with moderate to severe depression, the study indicated. "Perfect physical health is neither necessary nor sufficient," said the study's lead investigator Dilip V. Jeste, a geriatric psychiatrist of the University of California at San Diego. "There is potential for enhancing successful aging by fostering resilience and treating or preventing depression." Overall, the researchers found that a higher self-rating of successful aging was more likely among those with higher education, better cognitive function, better perceived physical and mental health, less depression and greater optimism and resilience. Previous studies have shown seniors tend to have quite positive outlooks — especially compared with younger adult generations — despite the physical and cognitive decline associated with old age. A 2008 analysis of data from the General Social Survey of the National Opinion Research Center indicated that about half of U.S. residents in their late 80s report being very happy, while the figure for younger adult age groups sinks to a third or less. And study of almost 45,000 German adults from 1984 to 2007 found that happiness levels dip during middle age but rebound by about age 60. Jeste led another study in 2005 that surveyed Americans ages 60 to 98 who had struggled with cancer, heart disease, diabetes, mental health conditions or a range of other problems. Even in the face of their ills, the participants rated their degree of successful aging quite high, which Jeste said at the time could be attributed to optimism and effective coping styles. Jeste, who is the current president of the American Psychiatric Association, said the results of the new study suggest aging doesn't have to be negatively viewed as a public health problem in the United States, where there are about 40 million adults over the age of 65. "There is considerable discussion in public forums about the financial drain on the society due to rising costs of health care for older adults — what some people disparagingly label the 'silver tsunami,'" Jeste said. "But, successfully aging older adults can be a great resource for younger generations."

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Volcanoes, Not Meteorite, Killed Dinosaurs, Scientist Argues

SAN FRANCISCO — Volcanic activity in modern-day India, not an asteroid, may have killed the dinosaurs, according to a new study. Tens of thousands of years of lava flow from the Deccan Traps, a volcanic region near Mumbai in present-day India, may have spewed poisonous levels of sulfur and carbon dioxide into the atmosphere and caused the mass extinction through the resulting global warming and ocean acidification, the research suggests. The findings, presented Wednesday (Dec. 5) here at the annual meeting of the American Geophysical Union, are the latest volley in an ongoing debate over whether an asteroid or volcanism killed off the dinosaurs about 65 million years ago in the mass die-off known as the K-T extinction. "Our new information calls for a reassessment of what really caused the K-T mass extinction," said Gerta Keller, a geologist at Princeton University who conducted the study. For several years, Keller has argued that volcanic activity killed the dinosaurs. But proponents of the Alvarez hypothesis argue that a giant meteorite impact at Chicxulub, Mexico, around 65 million years ago released toxic amounts of dust and gas into the atmosphere, blocking out the sun to cause widespread cooling, choking the dinosaurs and poisoning sea life. The meteorite may impact may also have set off volcanic activity, earthquakes and tsunamis. [Wipe Out: History's Most Mysterious Extinctions] The new research "really demonstrates that we have Deccan Traps just before the mass extinction, and that may contribute partially or totally to the mass extinction," said Eric Font, a geologist at the University of Lisbon in Portugal, who was not involved in the research. Sea cockroach In 2009, oil companies drilling off the Eastern coast of India uncovered eons-old lava-filled sediments buried nearly 2 miles (3.3 kilometers) below the ocean surface. Keller and her team got permission to analyze the sediments, finding they contained plentiful fossils from around the boundary between the Cretaceous-Tertiary periods, or K-T Boundary, when dinosaurs vanished. The sediments bore layers of lava that had traveled nearly 1,000 miles (1,603 km) from the Deccan Traps. Today, the volcanic region spans an area as big as France, but was nearly the area of Europe when it was active during the late Cretaceous period, said Adatte Thierry, a geologist from the University of Lausanne in France who collaborated with Keller on the research. Within the fossil record, plankton species got fewer, smaller and maintained less elaborate shells immediately after lava layers, which would indicate it happened in years after the eruptions. Most species gradually died off. In their wake, a hardy plankton genus with a small, nondescript exoskeleton, called Guembilitria, exploded within the fossil record. Keller's team found similar trends in their analysis of marine sediments from Egypt, Israel, Spain, Italy and Texas. While Guembilitria species represented between 80 percent and 98 percent of the fossils, other species disappeared. "We call it a disaster opportunist," Keller told LiveScience. "It's like a cockroach — whenever things go bad, it will be the one that survives and thrives." Guembilitria may have come to dominance worldwide when the huge amounts of sulfur (in the form of acid rain) released by the Deccan Traps fell into the oceans. There, it would've chemically binded with calcium, making that calcium unavailable to sea creatures that needed the element to build their shells and skeletons. Around the same time in India, fossil evidence of land animals and plants vanished, suggesting the volcanoes caused mass extinctions on both land and in the sea there. Global impact In past work, the team has also found evidence at Chicxulub that casts doubt on the notion of a meteorite causing the extinction. Sediments containing iridium, the chemical signature of an asteroid, show up after the extinction occurred, contradicting the notion that it could have caused a sudden die-off, Keller said. A meteorite impact also would not have produced enough toxic sulfur and carbon dioxide to match the levels seen in the rocks, so it may have worsened the mass extinction, but couldn't have caused it, she said.

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Hovering Drone Grabs Spotlight with 6-Foot Arm

Look out humans — a robot floating in midair with a 6-foot arm now exists outside the realm of science fiction films like "Star Wars." The U.S. military recently tested a hovering drone's ability to attach its claw to a target object. The "V-Bat" is a vertical takeoff and landing (VTOL) drone that can fly like a robotic aircraft and hover in place while standing upright on its tail, according to its makers at the MLB Company. The U.S. Defense Advanced Research Projects Agency funded work to make a "vision system" for V-Bat that allowed the hovering robot to attach its 1-pound claw to a ladder. "Our goal with the unmanned aerial vehicle payload emplacement demonstration was to show we could quickly develop and integrate the right technology to make this work," said Dan Patt, DARPA program manager. "The success of the demonstration further enables the capabilities of future autonomous, aerial vehicles." DARPA wants to construct future drones capable of precisely delivering small objects in tight spaces. V-Bat's vision system coordinated with the drone's onboard GPS so that the robot could approach and place its payload on the ladder as it hovered in midair. The successful experiment could turn drones into even more capable delivery messengers for both the U.S. military and civilian uses. U.S. Marines already get deliveries from robotic helicopters in Afghanistan, but soldiers must attach and detach the helicopter payloads manually. Many robot vision systems still struggle to accurately identify objects, let alone coordinate a midair handoff delivery. The experiment also proved challenging because a hovering robot does not necessarily represent the most stable platform. Many past hover vehicles have struggled to maintain stability in midflight. Still, the V-Bat had a backup advantage in case of an accidental tip-over. It could survive due to its nose protection and a duct shielding its rotor and vanes. The MLB Company's description of V-Bat suggests that the drone could one day carry out missions for the U.S. military ranging from aerial mapping to anti-piracy.

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Nail Salon Lamps Don't Raise Skin Cancer Risk

While the risk of developing skin cancer is known to be linked with exposure to ultraviolet light, it's been less clear whether the UV lamps used in nail salons might raise the risk of skin cancer. Now, a new study suggests these lamps don't increase skin cancer risk. In the study, researchers looked at three commonly used UV nail lamps. They measured the light, in terms of its likely carcinogenic effects, and calculated the "UV dose" that a user would receive during a 10-minute nail-drying session. Not all ultraviolet lamps are the same — for example, people with the skin condition psoriasis may be treated with lamps, and studies have shown these "narrowband UVB" treatments raise the risk of skin cancer only minimally, compared with the more damaging rays of tanning salon lamps. The new study showed that between 13,000 and 40,000 nail-drying sessions would be needed before a person would receive the same UV dose as a person with psoriasis who received light treatments for their condition, according to researchers Dr. Alina Markova, of the Massachusetts General Hospital in Boston, and Dr. Martin Weinstock, of Brown University. That's about 250 years of weekly manicures. The findings mean that using these UV lamps "does not produce a clinically signi?cant increased risk of developing skin cancer," the researchers wrote. Two previous studies have looked at this question, the researchers said. In a 2009 report, researchers concluded that UV nail lamps were a risk factor in the cases of two women who developed skin cancer known as squamous cell carcinomas on the backs of their hands. In the other study, a laboratory hired by the nail salon industry tested many UV nail lamps and concluded UV light levels emitted were low and safe. However, researchers of the new study noted that report about the two women was anecdotal, and did not include measurements of the UV light from the lamps. They also said the methods used in the industry-funded study were inappropriate. "Dermatologists and primary-care physicians may reassure patients regarding the safety of these devices," the researchers wrote in their article, published Thursday (Dec. 6) in the Journal of Investigative Dermatology.

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