- Why Alcohol Is Good For You
- Asteroid Double Whammy Near Earth Wednesday
- Photo: Galactic Cannibals Discovered in Deep Space
- Procrastination Pit: 8 Cutest and Weirdest Live Animal Cams
- Self-Healing Solar Cells Could Have Indefinite Lifespan
Posted: 07 Sep 2010 04:29 PM PDT
It's one of those medical anomalies that nobody can really explain: Longitudinal studies have consistently shown that people who don't consume any alcohol at all tend to die before people who do. At first glance, this makes little sense. Why would ingesting a psychoactive toxin that increases our risk of cancer, dementia and liver disease lengthen our lifespan?
Well, the anomaly has just gotten more anomalous: A new study, published in the journal Alcoholism: Clinical and Experimental Research, followed 1,824 participants between the ages of 55 and 65. Once again, the researchers found that abstaining from alcohol increases the risk of dying, even when you exclude former alcoholics who have now quit. (The thinking is that ex-drinkers might distort the data, since they've already pickled their organs.) While 69 percent of the abstainers died during the twenty-year time span of the study, only 41 percent of moderate drinks passed away. (Moderate drinkers were also 23 percent less likely to die than light drinkers.) But here's the really weird data point: Heavy drinkers also live longer than abstainers. (Only 61 percent of heavy drinkers died during the study.) In other words, consuming disturbingly large amounts of alcohol seems to be better than drinking none at all.
We live in a reductionist age, in which every longitudinal effect is explained away at the most fundamental possible level. And so this study will no doubt lead researchers to probe the benefits of red wine, with its antioxidants and resveratrol. It will also lead people to explore the cardiovascular benefits of alcohol, since many of the perks of drinking (such as increased levels of HDL cholesterol) seem to extend to people who drink beer and hard liquor.
These are all important hypotheses, the sort of speculations that assuage this drinker's heart. (I'm no Don Draper, but I certainly enjoy my evening IPA.) Nevertheless, I worry that in the rush to reduce, to translate the unexpected longitudinal effect into the acronyms of biochemistry, we'll miss the real import of the study.
Let's think, for a moment, about the cultural history of drinking. The first reason people consume booze is to relax, taking advantage of its anxiolytic properties. This is the proverbial drink after work – after a eight hours of toil, there's something deeply soothing about a dose of alcohol, which quiets the brain by up-regulating our GABA receptors. (But don't get carried away: While the moderate consumption of alcohol might reduce the stress response, blood alcohol levels above 0.1 percent — most states consider 0.08 the legal limit for driving — trigger a large release of stress hormones. Although you might feel drunkenly relaxed, your body is convinced it's in a state of mortal danger.) And so the stresses of the day seem to fade away – we are given a temporary respite from the recursive complaints of self-consciousness. Since chronic stress is really, really bad for us, finding a substance that can reliably interrupt the stress loop might have medical benefits.
But drinking isn't just about de-stressing. In fact, the cultural traditions surrounding alcohol tend to emphasize a second, and perhaps even more important, function: socializing. For as long people have been fermenting things, they've been transforming the yeasty run-off into excuses for big parties. From Babylonian harvest festivals to the bacchanalias of Ancient Greece, alcohol has always been entangled with our get togethers. This is for obvious reasons: Alcohol is a delightful social lubricant, a liquid drug that is particularly good at erasing our inter-personal anxieties. And this might help explain why, according to the new study, moderate drinkers have more friends and higher quality "friend support" than abstainers. They're also more likely to be married.
What does this have to do with longevity? In recent years, sociologists and epidemiologists have begun studying the long-term effects of loneliness. It turns out to be really dangerous. We are social primates, and when we're cut off from the social network, we are more likely to die from just about everything (but especially heart disease). At this point, the link between abstinence and social isolation is merely hypothetical. But given the extensive history of group drinking – it's what we do when we come together – it seems likely that drinking in moderation makes it easier for us develop and nurture relationships. And it these relationships that help keep us alive.
Of course, relationships have their own chemistry, a language of dopamine, oxytocin, vasopressin, etc. But I think that in the rush to decipher the bodily molecules, we are missing the essential lesson, which is that some of the most valuable health benefits don't come from compounds that can be bottled, or condensed into a gel capsule. Instead, they come from other people, from those lovely conversations we share over a glass or three of wine.
Surgeon General's Warning: Of course, these longitudinal correlations don't mitigate the negative, and frequently devastating, consequences of alcohol and alcoholism. Let's not forget that alcohol can be an addictive substance, and that, in many contexts, drinking promotes violence and thuggishness, and not polite socializing. It's also essential to note that all of the aforementioned health benefits of alcohol (such as de-stressing and socializing) can also be achieved for free, such as with meditation or by simply being a good friend.
Image: One of my favorite IPA's.
Posted: 07 Sep 2010 01:12 PM PDT
Get out your telescopes! Two small asteroids will come within moon distance of Earth Wednesday.
The first, asteroid 2010 RX30, will come within 154,100 miles of Earth — about 60 percent of the Earth-moon distance — at 5:51 a.m. EDT (1251 UT). This asteroid is estimated to be about 42 feet across.
The second, 2010 RF12, will come almost 12 hours later, at 5:12 p.m. EDT (0012 UT Thursday). It will swing by Earth at just 20 percent the Earth-moon distance, or 47,845 miles. 2010 RF12 is even smaller, only about 23 feet across.
Both were just discovered Sept. 5 by astronomer Andrea Boattini, working with a 1.5-meter reflecting telescope at Mount Lemmon in Arizona as part of the Catalina Sky Survey's routine scanning of the skies.
According to NASA's Near-Earth Object impact risk tables, the odds that 2010 RF12 will hit the Earth are about 1 in 50, and the odds of an impact with 2010 RX30 are less than 1 in 1,000. Both objects are too small to do much damage even if they were to smack into the Earth: Much of their rocky mass probably wouldn't survive the trip through Earth's atmosphere.
Because of their small sizes, they won't be visible with the naked eye. But they should be bright enough to observe with a modest-size telescope, according to the Near-Earth Object Program.
The two asteroids are on unrelated orbits. The fact that they're scheduled to arrive so close to each other is purely a cosmic coincidence.
Images: 1) Asteroid Ida as imaged by the Galileo spacecraft in 1993. Credit: NASA
Posted: 07 Sep 2010 10:52 AM PDT
Small galaxies, beware. A new survey caught several distant galaxies ripping up their dwarfish galactic neighbors and devouring them whole.
Astronomers have long thought this sort of intergalactic violence could be the normal way large galaxies grow. The Milky Way and the Andromeda galaxy, the two closest and best-known examples of spiral galaxies, are both known cannibals.
When a dwarf galaxy approaches a large spiral galaxy, the bigger galaxy's extra gravitational oomph strips gas, stars and dark matter from its hapless victim. Over a few billion years, the smaller galaxy is stretched like taffy into long strips or tendrils of stars.
"Within the hierarchical framework for galaxy formation, minor merging and tidal interactions are expected to shape all large galaxies to the present day," writes David Martínez-Delgado of the Max Planck Institute for Astronomy in Germany and colleagues in a new paper to be published in the October issue of the Astronomical Journal.
The Sagittarius stream around the Milky Way and the Great Southern stream around Andromeda are "archetype fossil records of satellite galaxy mergers," the authors add. But there aren't enough large galaxies in the Milky Way's immediate neighborhood, called the "Local Group" of galaxies, to quantify how common these galactic bullies really are. In the new study, Martínez-Delgado and colleagues observed eight spiral galaxies up to 50 million light-years away, well beyond the local group, to hunt for the galactic equivalents of bloodstains and fingerprints.
The images revealed six new star stream candidates that look like nothing astronomers have seen before. Some of the galaxies, like NGC 4651 (above) — also known as the Umbrella Galaxy — display enormous arcs of stars that resemble an open umbrella. This galaxy's stellar streams extend up to 50,000 light-years away from its center. The dwarf galaxy corpse had been detected by earlier observations, but had never been interpreted as a tidal stream.
The other galaxies in the survey showed a striking diversity in the shapes of their stellar streams, the authors write, including fuzzy clouds, great circles surrounding the larger galaxy and long spikes and plumes extending thousands of light-years from the galactic center.
"Each halo displays a unique and very complex pattern of stellar debris caused by different defunct companions," the researchers write.
The variety of shapes neatly matches the shapes predicted by computer simulations of galaxy formation, suggesting that current theories of how galaxies grow by swallowing their neighbors are on the right track.
All the observations were taken using backyard telescopes owned by amateur astronomers: 20-inch telescopes at Blackbird Observatory in New Mexico and Rancho del Sol in California, a 14.5-inch telescope in Moorook, South Australia, and a 6-inch telescope at New Mexico Skies.
Image: 1) R. Jay Gabany (Blackbird Obs.)/D. Martínez-Delgado (MPIA and IAC) et al. 2) D. Martínez-Delgado (MPIA). Left column from top to bottom: M 63, NGC 4651, NGC 7531, NGC 5866. Right column from top to bottom: NGC 1084, NGC 4651, NGC 3521, NGC 1055.
Posted: 07 Sep 2010 08:50 AM PDT
Posted: 07 Sep 2010 07:04 AM PDT
A new technique may one day lead to solar cells that bring themselves together like a molecular flash mob and repair damage they sustain during the rough business of turning light into electricity.
"It's a manmade version of what nature does," says nanocomposite expert Jaime Grunlan of Texas A&M University in College Station. "This really looks like ground-breaking seminal work; I've never seen anything remotely like it."
The sun's rays can be brutal, even for a leaf that's harvesting them. When photosynthesis is going full blast, a leaf is constantly building new photosynthetic reaction centers to replace those damaged by harsh oxygen species and other destructive molecules generated by intense ultraviolet light.
So rather than trying to make solar cells that are extremely durable, the team decided to take a literal leaf from nature's book and go the route of self-repair, says chemical engineer Michael Strano of MIT, who led the project. He and Stephen Sligar and Colin Wraight of the University of Illinois at Urbana-Champaign, along with other colleagues, designed a system where damaged parts could be easily replaced.
The researchers began with light-harvesting reaction centers from a purple bacterium. Then they added some proteins and lipids for structure, and carbon nanotubes to conduct the resulting electricity.
These ingredients were added to a water-filled dialysis bag — the kind used to filter the blood of someone whose kidneys don't work — which has a membrane that only small molecules can pass through. The soupy solution also contained sodium cholate, a surfactant to keep all the ingredients from sticking together.
When the team filtered the surfactant out of the mix, the ingredients self-assembled into a unit, capturing light and generating an electric current.
The spontaneous assembly occurs thanks to the chemical properties of the ingredients and their tendency to combine in the most energetically comfortable positions. The scaffolding protein wraps around the lipid, forming a little disc with the photosynthetic reaction center perched on top. These discs line up along the carbon nanotube, which has pores that electrons from the reaction center can pass through.
Adding the sodium cholate back into the mix disassembles the complexes. But filtering it out again brings them right back together.
"The idea that it happens reversibly and at will is quite amazing," says Strano. "It approaches what happens in biology — forming a huge amount of order with the flip of a switch. It's kind of like taking puzzle pieces and throwing them up in the air and them coming down assembled."
The complexes eventually lose power, but they are easily revived, says Strano. The research team disassembled the units and replenished the photosynthetic reaction centers. Four such replacements over the course of a week kept keeping the complexes humming along.
"This is very nice work — the procedure they've got, the control they have over the system," says biochemist Mike Jones of the University of Bristol in England. "It's simple, it's very nice."
The units can't compete with silicon-based solar cells in use today. But silicon-based solar cells reached their current level of efficiency only after decades of research and development, says Jones. Similar investment in this new technology could yield a system that's highly efficient, can self-repair and works well under low light conditions, he says.
What's more, the main ingredients for these solar cells might one day be easily extracted from plant material, says Strano, perhaps even from garbage biomass. "We could turn waste into an organized product," he says.
Images: 1) Flickr/Matt McGee. 2) M-H. Ham et al./Nature Chemistry.
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