2009 November 30 Monday
Abortion Does Not Change Brain Evolutionary Pressures?

Ron Guhname (not his real name), The Inductivist, used data from the General Social Survey to look at the question of whether the legalization of abortion in America caused a change in selective pressures for intelligence. Using the GSS Wordsum test as a rough measure of intelligence Ron finds that abortion did not appear to change the selective pressures for higher or lower intelligence. The selective pressures for lower intelligence continued unchanged.

The first year of the General Social Survey was 1972. I looked at white women ages 50 and over for all surveys conducted in the 70s. The mean number of kids for dull women (Wordsum 0-4) was 3.02. It was 2.22 for smart women (Wordsum 8-10). That's a ratio of 1.36. Looking at this decade, I calculated means for white women ages 45-59. For the unintelligent group, the mean number of kids is 2.38, and it's 1.76 for the bright group. That's a ratio of 1.35.

There is no difference between the two periods. The higher fertility of dull women seen prior to 1970 continues to the same degree today.

My guess is that women use the knowledge that they can get an abortion to become more lax about use of birth control and to enable more spontaneous beginnings of affairs. Abortion might still have caused changes in selective pressures because the women who are willing to go thru with an abortion might differ in some aspect of personality as compared to women who won't.

If you are curious about modern era selective pressures for intelligence see this report from an Australian twins study. For a book length treatment of selective pressures on humans see The 10,000 Year Explosion: How Civilization Accelerated Human Evolution by Gregory Cochran and Henry Harpending.

By Randall Parker 2009 November 30 09:55 AM  Brain Evolution
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Dan Neil Drives Chevy Volt

For those unaware, Dan Neil of the Los Angeles Times writes excellent car reviews. He's got one up from his own test drive of the forthcoming Chevrolet Volt pluggable hybrid electric vehicle.

It accelerates with a big husky twist of its electric motor. Actually, you can even chirp the front tires if you push the go-button hard enough -- very unlike a golf cart. It corners confidently and brakes crisply and, if it's no Ferrari, it certainly won't embarrass itself on the 110 Freeway, otherwise known as the Pasadena Grand Prix.

It's comfortable, practical and -- graded on the curve of five-seat family hatchbacks -- reasonably attractive. Think German-made-dishwasher pretty.

The big appeal of the Volt is it that if you drive less than 40 miles per day and don't mind plugging it into electric power every night then you never need buy gasoline. If you need to drive more than 40 miles it switches over to gasoline engine power. If GM can bring the cost of the Volt down far enough then for most commuters Peak Oil will become a non-event (though not so when it comes time to take a vacation and go on a week-end get-aways).

A lot of people expect short battery life in the Volt because batteries wear out in their laptop computers and cell phones. But Rob Peterson of GM Communications showed up here a few weeks ago to explain that the battery for the Volt is a very different design that GM expects will last 10 years or 150,000 miles.

Also, the Volt's battery is a purely automotive design - from the chemistry (li-ion mangnese spinel) based), cell design (prismatic as opposed to cylinder), pack management which restricts overcharging (which impacts calendar life)and deep discharges (which impacts battery power) to automotive quality manufacturing at both the cell and pack levels (both of which will eventually be performed in Michigan). We're increasingly confident - based on test results from both our battery lab and in the nearly 100 Chevy Volt pre-production vehicles - that the battery will meet our internal targets of 10 year, 150,000 miles of life.

Looks like GM can achieve their engineering goals in terms of efficiency, driveability, and durability. So I expect the long term success of the Volt to hinge on the costs of the pluggable hybrid technology. How much will costs of battery and drive train parts go down 5, 6, 7 years from now? Can we expect the Volt's manufacturing costs to ever get below $20k or, better yet, $15k?

By Randall Parker 2009 November 30 06:42 AM  Energy Electric Cars
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2009 November 29 Sunday
Siberian Tiger Numbers Down On Poaching, Habitat Loss

A familiar story for many species around the world.

NEW YORK (November 24, 2009) -- The Wildlife Conservation Society (WCS) announced today a report revealing that the last remaining population of Siberian tigers has likely declined significantly due to the rising tide of poaching and habitat loss.

WCS says the report will help inform Russian officials of what needs to be done to protect remaining populations of the world's biggest cat.

The report was released by the Siberian Tiger Monitoring Program, which is coordinated by WCS in association with Russian governmental and non-governmental organizations. It revealed that a recent tiger survey over a representative part of the tiger's range showed a 40 percent decline in numbers from a 12-year average.

Annual tiger surveys are conducted at 16 monitoring sites scattered across tiger range to act as an early warning system to detect changes in the tiger population. The monitoring area, which covers 9,000 square miles (23,555 square kilometers), represents 15-18 percent of the existing tiger habitat in Russia. Only 56 tigers were counted at these monitoring sites. Deep snows this past winter may have forced tigers to reduce the amount they traveled, making them less detectable, but the report notes a 4-year trend of decreasing numbers of tigers.

The scientists estimate that about 500 of these beasts remain.

I think an international effort should be made to collect many DNA samples from each threatened species so that even if the species go extinct in the wild the DNA could be studied, sequenced, and recorded. Then in some later century if human populations ever decrease enough to open up big areas for habitats then lost species could be reintroduced with the help of some embryo engineering.

Since the world's human population is headed toward over 9 billion people I believe we need to get realistic about the dismal prospects for habitat protection. If we admit to our future losses of species we'll have a better chance of organizing collection efforts to at least record the DNA sequences of these many species we are going to lose.

By Randall Parker 2009 November 29 07:42 PM  Trends Extinction
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Better Uranium Fuel Burn In Advanced Gas Reactor

In a research program for next generation Advanced Gas Reactor (AGR), uranium fuel burns far more efficiently than in existing light water reactors.

WASHINGTON, D.C. — Idaho National Laboratory (INL) scientists have set a new world record with next-generation particle fuel for use in high temperature gas reactors (HTGRs).

The Advanced Gas Reactor (AGR) Fuel Program, initiated by the Department of Energy in 2002, used INL's unique Advanced Test Reactor (ATR) in a nearly three-year experiment to subject more than 300,000 nuclear fuel particles to an intense neutron field and temperatures around 1,250 degrees Celsius.

INL researchers say the fuel experiment set the record for particle fuel by consuming approximately 19 percent of its low-enriched uranium — more than double the previous record set by similar experiments run by German scientists in the 1980s and more than three times that achieved by current light water reactor (LWR) fuel. Additionally, none of the fuel particles experienced failure since entering the extreme neutron irradiation test environment of the ATR in December 2006.

Higher fuel burn efficiency offers a few benefits. First off, more complete burn reduces the waste disposal problem. If 3 times as much of the uranium gets burned then the amount of waste produced goes down by a factor of 3 per amount of electricity produced - all else equal. Plus, this reduces cost of uranium since each amount of uranium produces much more electricity. Plus, if the fuel burns at the same rate then refueling happens less often and therefore reactors operate for longer between refuelings. This raises productivity and cuts costs.

Technological advances that cut the cost of nuclear power are good because if nuclear power costs fall below coal electric power costs then nuclear would gradually displace coal and we'd live in a less polluted and less environmentally damaged world.

By Randall Parker 2009 November 29 07:01 PM  Energy Nuclear
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Electric Engine Advantage: Nature Watching

Regular readers know I'm a big fan of a general movement toward more use of electric power for transportation, heating (using heat pumps), and for other applications where fossil fuels are currently used directly. Yesterday I discovered another reason to like electric motors: They are quieter on a river that is rich with wildlife. You end up finding more of the noisy wildlife.

In my case the wildlife was on the Silver River in Florida. In particular, we were looking for the Rhesus monkeys that are descendants of monkeys that escaped (I am told) from the sets of Tarzan movies back in the 1920s. We went up the river on internal combustion engine power and didn't find the monkeys. We couldn't use the electric motor because it wasn't powerful enough to make much speed up-river and the battery wouldn't last. But on the way back down river power of the electric engine was sufficient. We found one of the Rhesus money troops (easily 50 monkeys) because under electric power we could hear the sounds they make on the branches swinging from tree to tree.

What's needed once again: Better batteries. We could have put more lead acid batteries on the boat. But we would have needed to trade off on other things we carried. With better batteries and another Minn Kota electric motor we could have made the whole trip on electric power.

Parenthetically, we went all the way down to where the Ocklawaha River joins the Silver. The differences between the two rivers are stark and I wonder if either agricultural run-off into the Ocklawaha or the fishing allowed on the Ocklawaha explain the differences. The Silver has huge numbers of birds. We probably saw 20 bird species. It also has lots of turtles and alligators (all small fwiw). We went several miles up the Ocklawaha and saw 1 gator, no birds, no turtles, and no monkeys. What's with that? Overfishing or agricultural run-off or something natural?

You can also kayak on the Silver and we saw over a dozen kayakers and canoers. But we wanted to see both rivers and so went under engine power.

By Randall Parker 2009 November 29 06:24 AM  Energy Batteries
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2009 November 28 Saturday
Diabetes To Double In United States

An aging population costs lots of money to treat for all their diseases. Rejuvenation therapies would therefore save a lot of money for disease treatments. Our aging population will double the number of people with diabetes even without an increase in prevalence at each age.

In the next 25 years, the number of Americans living with diabetes will nearly double, increasing from 23.7 million in 2009 to 44.1 million in 2034. Over the same period, spending on diabetes will almost triple, rising from $113 billion to $336 billion, even with no increase in the prevalence of obesity, researchers based at the University of Chicago report in the December issue of Diabetes Care.

$336 billion per year to manage one disease. The idea here isn't that $336 billion will be spent to cure each patient. If methods of cure existed they'd probably cost far less than a few hundred billion per year. When cures exist they are usually much cheaper than managing a disease.

The number of those with diabetes covered by Medicare will rise from 8.2 million to 14.6 million, the researchers predict. Medicare spending on diabetes will jump from $45 billion to $171 billion.

"If we don't change our diet and exercise habits or find new, more effective and less expensive ways to prevent and treat diabetes, we will find ourselves in a lot of trouble as a population," said the study's lead author Elbert Huang, MD, assistant professor of medicine at the University of Chicago.

"Without significant changes in public or private strategies," the authors wrote, "this population and cost growth are expected to add a significant strain to an overburdened health care system."

If obesity rises then the cost will be higher. But if drugs come on the market that cut the incidence of obesity then the incidence of diabetes would plummet. Drugs that reverse the metabolic changes that cause adult-onset insulin resistant diabetes might also do the trick. I also wonder whether getting high fructose corn syrup out of our diets would cut the incidence of diabetes as well.

By Randall Parker 2009 November 28 07:56 PM  Trends Health
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2009 November 26 Thursday
Waist Fat Doubles Dementia Risk In Women

That tire rots your brain.

Women who store fat on their waist in middle age are more than twice as likely to develop dementia when they get older, reveals a new study from the Sahlgrenska Academy.

The study has just been published in the scientific journal Neurology.

"Anyone carrying a lot of fat around the middle is at greater risk of dying prematurely due to a heart attack or stroke," says Deborah Gustafson, senior lecturer at the Sahlgrenska Academy. "If they nevertheless manage to live beyond 70, they run a greater risk of dementia."

The research is based on the Prospective Population Study of Women in Gothenburg, which was started at the end of the 1960s when almost 1,500 women between the ages of 38 and 60 underwent comprehensive examinations and answered questions about their health and lifestyle.

What I wonder: What's the long term effect of liposuction? Does it decrease any risks associated with abdominal fat? Or do risks perhaps even increase because then more excess calories turn into intra-abdominal fat around internal organs?

What I also wonder: Is the waist fat risk really due to the fat near the skin? Or is that fat just a proxy also indicating the presence of far more dangerous intra-abdominal fat around internal organs? Could be both.

I ask all these questions about intra-abdominal fat because fat deposited around your organs makes those organs perform poorly.

(Boston) - Researchers from Boston University School of Medicine (BUSM) have shown that fat collection in different body locations, such as around the heart and the aorta and within the liver, are associated with certain decreased heart functions. The study, which appears on-line in Obesity, also found that measuring a person’s body mass index (BMI) does not reliably predict the amount of undesired fat in and around these vital organs.

So how to keep the weight off inside your body where fat is most harmful? So far the only way I know to do it is exercise after a diet. If you go on a diet and lose weight then exercise will keep the weight off around internal organs.

By Randall Parker 2009 November 26 08:49 AM  Aging Diet Weight Studies
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2009 November 25 Wednesday
Deep Retrofits For Housing Efficiency

An Oak Ridge National Laboratory program to do deep retrofits of housing for energy efficiency comes up with an average $20k price tag. How can this pay itself back?

Deep energy retrofits are renovations to existing structures that use the latest in energy-efficient materials and technologies and result in significant energy reductions. Jeff Christian, the ORNL buildings technologies researcher heading the project, said at least 10 homes across the region will be sought to participate. The home selection process is yet to be finalized, and homeowners will have to pay most of the costs—about $10 per square foot of living space—and agree to allow their post-retrofit energy consumption to be monitored. But Christian said costs can be recovered in as little as 10 years, and energy bills potentially can be cut in half. Most important, data from the project can provide huge incentives for more deep retrofits across the region, he said.

So for a 2000 square foot house the total cost is $20,000. Any readers have a house about that big? How much are your yearly energy bills? I'm skeptical of a 10 year payback time for a retrofit that is so expensive. In fact, I went to a mortgage calculator, specified a 10 year, $20,000, 6% loan (too high or low?) and got a monthly payment rate of $222. Someone would to have a monthly average energy bill of $444 to cut in half with retrofits to pay it back in 10 years. Does anyone have an energy bill that large on a 2000 square foot house? Setting the payback time to 20 years the monthly payment comes out to $143. Got a monthly $286 average bill for electricity and natural gas or heating oil?

I wonder whether they include the solar panels mentioned below in this retrofit.

The retrofits are part of an energy-efficient systems approach that involves making the building more air-tight; weatherizing the attic, crawl space and windows; upgrading heating and cooling units, water heaters, appliances and lighting; and installing solar panels.

Oak Ridge is in Tennessee which can have some pretty hot summers. So they are looking for big savings from reworking how the house and attic get cooled. Got a big air conditioning bill?

Christian explained many new two-story houses have a heat pump for downstairs and another in the attic for upstairs. Much of the cost of cooling conventional houses comes from the unit in the hot attic operating very inefficiently. In a retrofit house, insulation is removed from the attic floor. The roof and sides of the attic are sealed with insulating foam, and a high-efficiency heat pump is installed in the attic. The result: huge energy savings in heating and cooling because the entire HVAC system is inside the insulation layer.

If you ever build a home from scratch then build it for high energy efficiency. Retrofitting is a lot more expensive.

Update: The 8 year payback time must be due to the subsidy paid by the taxpayers. As a few commenters point out, the rest of us pay for this. I'm with them in thinking this subsidy is a bad idea. Most of the energy savings can be had for a small portion of the total $20k cost. Think about that. Spend the same $20k over several houses and the total energy savings would be much larger.

If ORNL wanted to do something useful with taxpayers money about home energy efficiency they'd come up with methods everyone could use to analyse their house to determine what are the low hanging fruit.

By Randall Parker 2009 November 25 08:48 PM  Energy Heating
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Rapidly Expanding Suburbs Start Contracting

Some former fast track suburbs have lost population since the recession started.

The recession and housing collapse have halted four decades of double-digit growth for nearly half of the nation's biggest rapidly expanding suburbs. Twenty-four of the 53 cities of 100,000 or more that grew by at least 10% every decade since 1970 lost population in the last two years.

This is blamed on the recession. But I think the oil price peak in the summer of 2008 (which by itself was enough to trigger a recession and we are at risk for a repeat) scared a lot of people out of willingness to move somewhere that requires long commutes.

Some commentators predict a return of ex-urb dwellers back into cities. But some employers could instead opt to move the jobs closer to the people. It is just as easy to build office buildings in an ex-urb as it is to build high density (and therefore very unpreferred) housing near an old city's office buildings.

Businesses probably move less frequently than employees because a business has all its existing employees who live nearer its existing location to worry about. But smaller businesses have an easier time moving, especially those who have most of their key employees coming in from the same distant area.

The advantage for a company that moves out to an area with cheaper housing is that it suddenly becomes a more attractive place to work for people who can't afford the more expensive housing of inner suburbs. So I wonder how fast will high oil prices drive some businesses out to the distant suburbs of older cities. Any thoughts on this?

By Randall Parker 2009 November 25 08:24 PM  Trends Housing
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2009 November 24 Tuesday
Space Exploration Takes Too Long For Democracies?

Will China's lack of democracy give it a leg up in the next wave of human space exploration? Michael Hanlon argues the next big step in space exploration takes too much time for a democracy to fund it.

It may simply be that space exploration is incompatible with US democracy. A Mars shot would take four presidential terms at least. No president will ask taxpayers to fund something he won't be around to take credit for.

He's probably right given the way we've approached space exploration to date. As long as we approach space exploration as something to do with small incremental improvements in technology we are going to spend vast sums for stunts of little lasting significance (e.g. the Apollo program to the Moon). I question the utility of spending 16 years and large sums of money to go to Mars for a brief human visit.

I think in terms of enabling the next big step in human colonization. Why go if you can't stay? We really need to develop far cheaper technologies for space launch and space travel. Spending big money to develop conservatively designed rockets for a Mars trip does not develop the level of technology we need to move enough stuff and safely move enough people to Mars to set up a permanent colony.

The Apollo program and moon shots should teach us that getting to some place at high cost per trip and without staying power ends up turning into a short term stunt that leaves no enduring presence off-planet. Great video. Some cool rocks. But then no further action for decades.

The space shuttle and space station are boring and not accomplishing much.

Another big problem is the legacy of some terrible decisions that left NASA with the expensive, dangerous space shuttle and a white-elephant space station that manages the feat of making space seem as dull as cardboard. The whole thing is a mess.

The space shuttle is old technology and highly cost ineffective. Funding it has provided video footage of people hurling into space. But it hasn't done anything to advance the state of the art for space launch for a very long time.

Funding the usage of old space technology is a waste that is done as a form of entertainment. The proposed Mars mission would use pretty conventional technology for space launch and for interplanetary travel. I see this as a waste of time. We need bigger steps forward that can lower costs and drastically cut risks. A space elevator made using nanotechnology could radically slash the cost of reaching low Earth orbit. To get to Mars a nuclear electric plasma propulsion system could transport humans in less than 6 weeks.

For humans to travel safely to Mars and beyond, it will be important to make the trip as quickly as possible and thereby reduce the crew's exposure to weightlessness and space radiation. With today's chemical rockets, a round-trip to Mars would take over two years, with much of that time spent waiting for the right planetary alignment to return. More rapid transits are possible with a VASIMR® propulsion system powered by a nuclear-electric generator. With 12 megawatts of electrical power, a ship could reach Mars in less than four months and with 200 megawatts of power the outbound trip could be as short as 39 days.

Our first priority for space exploration should be the development of technologies that make a human presence off-planet sustainable and low risk. Fast cheap safe transportation is a key piece of the puzzle.

By Randall Parker 2009 November 24 06:57 PM  Space Exploration
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2009 November 23 Monday
Stem Cells Reduce Severe Angina Heart Pain

A person's own purified adult stem cells can reduce pain from a form of heart disease.

CHICAGO --- The largest national stem cell study for heart disease showed the first evidence that transplanting a potent form of adult stem cells into the heart muscle of subjects with severe angina results in less pain and an improved ability to walk. The transplant subjects also experienced fewer deaths than those who didn't receive stem cells.

In the 12-month Phase II, double-blind trial, subjects' own purified stem cells, called CD34+ cells, were injected into their hearts in an effort to spur the growth of small blood vessels that make up the microcirculation of the heart muscle. Researchers believe the loss of these blood vessels contributes to the pain of chronic, severe angina.

"This is the first study to show significant benefit in pain reduction and improved exercise capacity in this population with very advanced heart disease," said principal investigator Douglas Losordo, M.D., the Eileen M. Foell Professor of Heart Research at the Northwestern University Feinberg School of Medicine and a cardiologist and director of the program in cardiovascular regenerative medicine at Northwestern Memorial Hospital, the lead site of the study.

I looki\ forward to seeing lots of stem cell therapies move into clinical use. Stem cells will displace long term drug use for many problems because the stem cells will be able to repair and not just manage a problem.

By Randall Parker 2009 November 23 09:39 PM  Biotech Heart Cardiovascular
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Toba Supervolcano Deforested India 73,000 Years Ago

About 73,000 years ago (74,000 by some estimates) a massive volcano on the Indonesia island of Sumatra erupted with a volcanic explosivity index (VEI) of 8. Such an eruption is so severe in its effects it basically would cause the deaths of billions of people today. New evidence finds that Toba's eruption caused deforestation in what is now central India.

CHAMPAIGN, Ill. — A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, researchers report.

The 800 cubic kilometers of ash ejected by Toba compares with the mere 160 cubic kilometers ejected by the 1815 Tambora eruption. The larger Toba eruption caused an ice age that lasted 1,800 years.

The volcano ejected an estimated 800 cubic kilometers of ash into the atmosphere, leaving a crater (now the world's largest volcanic lake) that is 100 kilometers long and 35 kilometers wide. Ash from the event has been found in India, the Indian Ocean, the Bay of Bengal and the South China Sea.

The bright ash reflected sunlight off the landscape, and volcanic sulfur aerosols impeded solar radiation for six years, initiating an "Instant Ice Age" that – according to evidence in ice cores taken in Greenland – lasted about 1,800 years.

During this instant ice age, temperatures dropped by as much as 16 degrees centigrade (28 degrees Fahrenheit), said University of Illinois anthropology professor Stanley Ambrose, a principal investigator on the new study with professor Martin A.J. Williams, of the University of Adelaide. Williams, who discovered a layer of Toba ash in central India in 1980, led the research.

We are not prepared for such an event today. Even 5 or 10 years to prepare could at most save a small fraction of the human race.

The 1815 Tambora VEI 7 eruption caused crop failures for 2 years. Imagine that happening today with nearly 7 billion humans using a much larger fraction of total planetary biomass. If a VEI 7 eruption could somehow be predicted several years in advance then industrialized nations could stockpile enough food to make it thru the crop failures. But poorer nations would face starvation on a scale not seen in the last 100 years.

Since geologists can't predict VEI 7 and up eruptions years in advance I do not expect we'll possess the ability to handle such an eruption until nanotechnology enables such huge increases in living standards that it becomes possible to very cheaply produce huge amounts of excess food and very cheap ways to store it for years.

By Randall Parker 2009 November 23 08:58 PM  Dangers Natural Geological
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2009 November 22 Sunday
Some Obese See Themselves As Healthy

Some obese people even think they could gain weight.

ORLANDO, FLA., Nov. 17, 2009 — Some obese people misperceive that their body size is normal and think they don’t need to lose weight, according to research presented at the American Heart Association’s Scientific Sessions 2009.

In the Dallas Heart Study of 5,893 people, researchers found that 8 percent of the 2,056 who were obese said they were satisfied with their body size or felt they could gain weight.

“Almost one in 10 obese individuals are satisfied with their body size and didn’t perceive that they need to lose weight,” said Tiffany Powell, M.D., lead author of the study and a cardiology fellow at the University of Texas Southwestern Medical Center in Dallas. “That is a sizeable percentage who don’t understand they are overweight and believe they are healthy.”

Obesity contributes to a lot of health problems including breast cancer, prostate cancer and pancreatic cancer. So body weight delusions kill.

Update: Since obesity and blood risk factors are increasing delusions about weight are becoming more costly.

In a new study, researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 1988–2006, representing 8,264 adult men and women, 20 to 85 years old. All had complete risk factor profiles of their blood pressure, fasting glucose, low density lipoprotein (LDL or “bad” cholesterol) and smoking status.

Researchers found that during this time period, the average body mass index (BMI) increased from 26.5 to 28.8 kg/m2, a significant change. BMI – a measure of body fatness – is calculated by dividing a person’s weight in kilograms by height in meters squared. In the same period, the number of people with optimal blood pressure decreased from 48 percent in NHANES III, 1988–94, to 43 percent in NHANES in 2005–06, and the number of people with optimal fasting glucose decreased from 67 percent to 58 percent. Both blood pressure and blood glucose are closely linked to obesity and these adverse trends track with the change in body weight.

By Randall Parker 2009 November 22 08:12 PM  Aging Weight Studies
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Mixed Genetic Ancestry And Mating

Mexicans and Puerto Ricans of mixed races tend to marry those of similar racial mix ratios.

A team led by Neil Risch and Esteban González Burchard of the University of California, San Francisco, took DNA samples from married couples in Mexican and Puerto Rican populations, examining around 100 genetic markers from across the genome. From these markers, the researchers were able to discern the proportions of Native American, European and African ancestry for each person.

They found that within Mexican populations, people tended to pick partners with similar proportions of Native American and European ancestry, while in Puerto Rican populations couples had paired up based on their shared balance of European and African ancestry.

Some easily measured physical characteristics do not appear to explain all of the mate selection results. How about sense of smell?

Quite how our DNA influences our desires remains mysterious. Risch and his colleagues did not find that geography or socio-economic status could explain the ancestral influence on romance, and factors like hair, eye and skin colour individually only had a minor role. According to Burchard, "Certainly physical characteristics, such as skin pigment, hair texture, eye color, and other physical features are correlated with ancestry and are likely to be factors in mate selection. However, the spouse correlation for these traits and the correlation of these traits with ancestry were actually below what would be required to fully explain the phenomenon".

Socioeconomic profile did not explain the mating patterns as well as genetic markers. I'd like to know what causes these results. I can imagine a number of genetic mechanisms by which mating preferences would track with genetic markers. Among the potential explanations that come to mind:

  • Genetic sequences might code for preferences for facial shapes, skin color, and other visible attributes.
  • Parental facial features and other physical features get imprinted on a baby and that causes the baby to prefer others who have similar features. So the brain doesn't directly code for preferences but (rather like Konrad Lorenz's geese) we are sensitive toward imprinting at some stage of development.
  • Genetic sequences might code for personality and cognitive attributes that track with the genetic markers. People might be attracted to similar personalities.
  • Settling. Preferences might not differ but competition results in like marrying like.

I would like to see studies done that use a combination of genetic marker comparison and pictures of people to see to what extent physical attraction tracks with similarity of genetic markers. To distinguish between the first two explanations above children of transracial adoptions could be included in the study.

Has much imprinting research been done about human attraction across races?

By Randall Parker 2009 November 22 06:54 PM  Brain Beauty
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2009 November 21 Saturday
Solexant To Sell Solar Cells At $1 Per Watt

Using nanocrystal-based inks printed onto metal foil photovoltaics start-up Solexant claims it can get its costs under those of low cost leader First Solar.

Making the entire cell using a roll-to-roll process gives the company an advantage over other thin-film photovoltaic companies that print on glass, which is heavier and limited to smaller areas, says Solexant CEO Damoder Reddy. "The cost benefit is dramatic, allowing us to produce cells for 50 cents a watt," he says. First Solar, a thin-film company that uses vacuum deposition to print its cells onto glass, has manufacturing costs of 85 cents per watt. Nanosolar, another company making nanocrystal solar cells, uses a different semiconductor that requires chemical reactions to take place during printing, which increases the complexity and expense of the process. "We print a preformed semiconductor," which eliminates such steps, says Reddy.

Nanosolar is the solar cell maker to beat on costs. I am optimistic about continued big price declines for solar cells because a number of venture capital start-ups like Nanosolar, Solyndra, and Solexant are making credible claims for PV fabrication approaches that enable lower cost manufacturing.

I worry about the approach of Peak Oil (and the possibility that world oil production has already peaked). Because of Peak Oil we need to shift more energy usage to electricity. But our biggest problem isn't how to generate more electricity. We can build nukes and wind turbines. Even solar power is going to become competitive in some areas. Our biggest problem is how to make electricity more usable for transportation. We can electrify the rails to move freight without using oil and lay more rails. But we need better cheaper batteries. It is still not clear to me that batteries will improve fast enough to make the transition away from oil for personal transportation easy enough.

By Randall Parker 2009 November 21 09:40 AM  Energy Solar
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Nanoparticles For Gene Therapy

An MIT press release about the use of nanoparticles to deliver gene therapy contains an interesting statistic about the size of the overall effort to develop clinically useful gene therapies: In the United States alone almost 1000 gene therapy clinical trials are underway. That's a surprisingly large number. Is it true? Seems too high to be possible.

There are nearly 1,000 clinical trials under way in the United States involving gene therapy, for diseases including cancer, cardiovascular disease and neurological disorders. However, no gene therapy treatments have been approved in the United States.

This is an example of why it is hard to predict the future. It is hard to predict the success rate of those many attempts. Once some succeed we also do not know how much of the successful techniques for a particular disease target will be reusable against other diseases. Gene therapy researchers in the early 1990s sounded pretty optimistic. But their high hopes were repeatedly dashed in failed experiments. Is success just around the corner or another 15 years away? For some of us (though we mostly do not know it yet personally) the answer is a matter of life and death.

Gene therapy has huge potential because it delivers instructions. Most diseased cells could be restored to a non-diseased state if they could only be sent enough instructions on how to repair themselves. Cell therapies get more press in part because of the ethical debate about embryonic stem cells. But gene therapies are crucial for rejuvenation because of the need to repair damaged brain cells. Lots of organs will some day just be replaced by organs grown in special vats. But the brain replacement is effectively person replacement. You have get your brain repaired in order to save your identity from death by aging.

The MIT press release on nanoparticles for gene therapy delivery sounds promising because these researchers at MIT and U Wisc have automated the process of searching the potential solution space by making large numbers of nanoparticle variations,

Anderson and chemist David Lynn, then a postdoctoral fellow in Langer’s lab and now a professor at the University of Wisconsin, developed a large collection of different biodegradable polymers (large molecules composed of repeating subunits) known as poly(beta-amino esters).

When these synthetic polymers are mixed with DNA, they spontaneously assemble to form nanoparticles. These nanoparticles can travel through the body to the target cells, where they are taken up by a process known as endocytosis, the equivalent of cellular eating. Once “eaten” by the cells, the nanoparticles release their DNA payload inside of the cell, where it can then be activated by the cellular machinery. In some ways, these polymer-DNA nanoparticles can act like an artificial virus, delivering functional DNA when injected into or near the targeted tissue.

There are infinite possible sequences for such polymers, and small variations can make a polymer more or less efficient at delivering DNA. Anderson and Langer's group have developed a way to automate both the production of vast numbers of particles with slight variations and the screening techniques used to determine the particles’ effectiveness.

“Instead of trying to make one perfect polymer, we make thousands,” says Anderson. That increases the odds that the researchers will hit on a nanoparticle that does what they want.

Will they succeed in developing useful gene therapy delivery vehicles? I hope so.

By Randall Parker 2009 November 21 05:21 AM  Biotech Gene Therapy
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2009 November 18 Wednesday
Anxiety Lowers Mortality Of The Depressed?

The direction of causation is not clear but a little bit of anxiety might be good for your health. Depressed smokers must have terrible life expectancy.

A study by researchers at the University of Bergen, Norway, and the Institute of Psychiatry (IoP) at King's College London has found that depression is as much of a risk factor for mortality as smoking.

Utilising a unique link between a survey of over 60,000 people and a comprehensive mortality database, the researchers found that over the four years following the survey, the mortality risk was increased to a similar extent in people who were depressed as in people who were smokers.

Dr Robert Stewart, who led the research team at the IoP, explains the possible reasons that may underlie these surprising findings: 'Unlike smoking, we don't know how causal the association with depression is but it does suggest that more attention should be paid to this link because the association persisted after adjusting for many other factors.'

The study also shows that patients with depression face an overall increased risk of mortality, while a combination of depression and anxiety in patients lowers mortality compared with depression alone. Dr Stewart explains: 'One of the main messages from this research is that 'a little anxiety may be good for you'.

I expect people who are more prone to worry are also more prone to worry about their diet, their weight, the quality of the air they breathe, and other factors that influence their health. A worrier would be more likely to get tested for weird lumps and abnormal skin growths. A worrier would be more likely to avoid developing unhealthy habits. So I'm not surprised by these results.

By Randall Parker 2009 November 18 10:43 PM  Aging Studies
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CO2 Might Boost Geothermal Energy Efficiency

Fracturing rocks deep underground so that water can be heated up doesn't work well for generating geothermal energy. The US Department of Energy has decided to fund some national labs to develop an approach for geothermal energy capture involving carbon dioxide as a substitute for water. The approach offers the additional benefit of sequestering CO2.

In 2000, Los Alamos National Laboratory physicist Donald Brown proposed replacing water with supercritical carbon dioxide, a pressurized form that is part gas, part liquid. Supercritical CO2 is less viscous than water and thus should flow more freely through rock. Brown noted that a siphoning effect should help cycle the carbon dioxide, thanks to the density difference between the supercritical CO2 pumped down and the hotter gas coming up, slashing power losses from pumping fluid. Plus, Brown argued, instead of using precious fresh water resources, a carbon dioxide-based project could sequester the equivalent of 70 years worth of CO2 emissions from a 500 megawatt coal power plant.

In the on-going debate about substitutes for fossil fuels the main candidates are solar, wind, and nuclear. Geothermal just doesn't get much attention. Anyone know why?

By Randall Parker 2009 November 18 10:22 PM  Energy Geothermal
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2009 November 17 Tuesday
Less Fearful Babies More Likely To Become Criminals

Babies less prone to feel fear are more likely to commit crimes.

Even at the tender age of 3, children who will go on to be convicted of a crime are less likely to learn to link fear with a certain noise than those who don't. This may mean that an insensitivity to fear could be a driving force behind criminal behaviour.

Adult criminals tend to be fearless, but whether this characteristic emerges before or after they commit a crime wasn't clear, says Adrian Raine, a psychologist at the University of Pennsylvania in Philadelphia.

Will people choosing genetic alleles for their genetically engineered children make them more or less predisposed to feel fear than the average human today? The answer will at least partially determine whether embryo selection for preferred genes will make future humans more or less criminal than they are today.

Raine does a lot of interesting work on innate causes of behavior. See my posts Brain Scans Show Abnormalities In Psychopaths and Habitual Liar Brains Look Different On Scans for more interesting brain research from Raine.

By Randall Parker 2009 November 17 10:12 PM  Brain Innate
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Folic Acid Boosts Cancer Risk?

A vitamin boosts cancer risk?

Patients with heart disease in Norway, a country with no fortification of foods with folic acid, had an associated increased risk of cancer and death from any cause if they had received treatment with folic acid and vitamin B12, according to a study in the November 18 issue of JAMA.

Most epidemiological studies have found inverse associations between folate (a B vitamin) intake and risk of colorectal cancer, although such associations have been inconsistent or absent for other cancers, according to background information in the article. “Experimental evidence suggests that folate deficiency may promote initial stages of carcinogenesis, whereas high doses of folic acid may enhance growth of cancer cells. Since 1998, many countries, including the United States, have implemented mandatory folic acid fortification of flour and grain products to reduce the risk of neural-tube birth defects,” the authors write. “Recently, concerns have emerged about the safety of folic acid, in particular with respect to cancer risk.”

Med Page Today has a more detailed breakdown of the statistical results.

Foods naturally high in folic acid might still be beneficial since greens, for example, have lots of other nutrients in them. But efforts to convert refined foods into high vitamin foods might be problematic. Eat your greens and beans for higher folic acid in foods that have a lot of other things going for them.

By Randall Parker 2009 November 17 09:54 PM  Aging Diet Cancer Studies
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Tougher Tasks Boost Performance Of Easier Ones

People work harder on their current task when they have a tougher task coming up.

Consumers will work harder on a task if they're expecting to have to do something difficult at a later time, according to a new study in the Journal of Consumer Research.

In today's fast-paced world, consumers frequently undertake unrelated tasks in a sequence. An individual might make a grocery list, decide whether to take out a home improvement loan, search the Internet for a vacation spot, and choose a dinner location—all before preparing lunch. "It seems reasonable to expect that when consumers know that they will have to work hard on a future task, they will devote less effort to the current task, in order to save energy for the upcoming demanding task. This is not what we found," write authors Anick Bosmans, Rik Pieters (both Tilburg University, The Netherlands), and Hans Baumgartner (Pennsylvania State University).

In a series of five studies, the authors observed that the more difficult a future task was expected to be, the harder consumers worked on a current task. "For example, consumers consulted more information on a web page when they were asked to evaluate a new soft drink when they expected that they would later on have to work on a difficult and demanding task," write the authors. Other participants were better able to come up with weight loss ideas when they believed they would have to work hard on a future job.

I've noticed this in my own performance. Faced with a difficult task I'm more efficient at getting through easier tasks even when I do not need to complete the easier tasks before doing the difficult one.

If you want to raise your overall performance then consider giving yourself more challenging tasks to do.

By Randall Parker 2009 November 17 09:32 PM  Brain Performance
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2009 November 16 Monday
Oxytocin Receptor Variants Linked To Empathy

In a sample of 200 students those with two copies of a particular allele of an oxytocin receptor appear to be better at reading emotional state in others.

CORVALLIS, Ore. – Researchers have discovered a genetic variation that may contribute to how empathetic a human is, and how that person reacts to stress. In the first study of its kind, a variation in the hormone/neurotransmitter oxytocin's receptor was linked to a person's ability to infer the mental state of others.

Interestingly, this same genetic variation also related to stress reactivity. These findings could have a significant impact in adding to the body of knowledge about the importance of oxytocin, and its link to conditions such as autism and unhealthy levels of stress.

Does the ability to read others cut or increase stress? I can see it cutting both ways. Sometimes obliviousness would be an advantage if everyone around you was anxious or depressed. Picking up on their signals would tend to bring you down. On the other hand, sometimes it is dangerous not to be able to read the emotional signals of others.

Can you read the minds of others?

One of the tests used to measure empathy included the "Reading the Mind in Eyes" test, created by Simon Baron-Cohen (cousin of actor/comedian Sacha Baron Cohen). Rodrigues said that this test is commonly used to discern how individuals can put themselves into the mind of another person, which overlaps with empathy, because it tests how well the participant can infer someone's emotional state by their eyes.

"In general, women do better on this test than men," Rodrigues said. "But we found a stark difference in both sexes based on the genetic variation." Those with the GG genetic variation were 22.7 percent less likely to make a mistake on the "Reading the Mind in the Eyes" test than the other individuals.

The article mentions a previous research report that found oxytocin spray given to autistics boosted the scores on behavioral and dispositional empathy measures. I'd like to know whether everyone would get a boost of greater social competence from a snort of oxytocin.

A variety of mental states have utility in different forms. Sometimes you just need to be a calculator. Sometimes you need to be a logic chopper. Other times you need to be a able to read people like a bunch of open books. It'd be helpful to be able to shift around into different useful mental states depending on the circumstances.

By Randall Parker 2009 November 16 11:26 PM  Brain Genetics
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Low Vitamin D Boosts Heart Death Risks?

Okay, weeks have gone by without a vitamin D post. Well, with big turkeys on the horizon it is time to think about heart health. Patients over 50 years old with the lowest vitamin D levels died at higher rates.

MURRAY, UT – While mothers have known that feeding their kids milk builds strong bones, a new study by researchers at the Heart Institute at Intermountain Medical Center in Salt Lake City suggests that Vitamin D contributes to a strong and healthy heart as well – and that inadequate levels of the vitamin may significantly increase a person's risk of stroke, heart disease, and death, even among people who've never had heart disease.

For more than a year, the Intermountain Medical Center research team followed 27,686 patients who were 50 years of age or older with no prior history of cardiovascular disease. The participants had their blood Vitamin D levels tested during routine clinical care. The patients were divided into three groups based on their Vitamin D levels – normal (over 30 nanograms per milliliter), low (15-30 ng/ml), or very low (less than 15 ng/ml). The patients were then followed to see if they developed some form of heart disease.

Researchers found that patients with very low levels of Vitamin D were 77 percent more likely to die, 45 percent more likely to develop coronary artery disease, and 78 percent were more likely to have a stroke than patients with normal levels. Patients with very low levels of Vitamin D were also twice as likely to develop heart failure than those with normal Vitamin D levels.

Those are startling differences. But what is the direction of causation?

If men have low vitamin D and low estrogen (yes, that's right, estrogen) then that's bad news for arteries.

Researchers at Johns Hopkins are reporting what is believed to be the first conclusive evidence in men that the long-term ill effects of vitamin D deficiency are amplified by lower levels of the key sex hormone estrogen, but not testosterone.

In a national study in 1010 men, to be presented Nov. 15 at the American Heart Association's (AHA) annual Scientific Sessions in Orlando, researchers say the new findings build on previous studies showing that deficiencies in vitamin D and low levels of estrogen, found naturally in differing amounts in men and women, were independent risk factors for hardened and narrowed arteries and weakened bones. Vitamin D is an essential part to keeping the body healthy, and can be obtained from fortified foods, such as milk and cereals, and by exposure to sunlight.

"Our results confirm a long-suspected link and suggest that vitamin D supplements, which are already prescribed to treat osteoporosis, may also be useful in preventing heart disease," says lead study investigator and cardiologist Erin Michos, M.D., M.H.S.

Do you think you ought to take vitamin D but just do not seem to get around to starting the habit?

By Randall Parker 2009 November 16 10:52 PM  Aging Diet Heart Studies
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2009 November 15 Sunday
Genome 10K Project To Sequence 10000 Species

Out of the 60,000 vertebrate species still in existence an international group of scientists wants to sequence 10,000 of them.

Scientists have an ambitious new strategy for untangling the evolutionary history of humans and their biological relatives: a genetic menagerie made of the DNA of more than 10,000 vertebrate species. The plan, proposed by an international consortium of scientists, is to obtain, preserve, and sequence the DNA of approximately one species for each genus of living mammals, birds, reptiles, amphibians, and fish.

A bigger effort is needed to collect samples from many individual animals of each species so that their genetic diversity can be preserved in the face of declining numbers. Habitat loss is cutting into the numbers of many species. For some only the DNA samples will exist as the living species go extinct.

They think they can do this for about $5000 per species.

Known as the Genome 10K Project, the approximately $50 million initiative is “tremendously exciting science that will have great benefits for human and animal health,” Haussler said. “Within our lifetimes, we could get a glimpse of the genetic changes that have given rise to some of the most diverse life forms on the planet.”

The idea is to compare DNA sequences across the many vertebrate species to get idea of which genes can be traced back to common ancestors hundreds of millions of years ago. This effort will likely change the way that trees get drawn to show the relationships between species.

The orders of magnitude decline in DNA sequencing costs make this project possible.

The primary impetus behind the proposal is the rapidly expanding capability of DNA sequencers and the associated decline in sequencing costs. “We’ll soon be in a situation where it will cost only a few thousand dollars to sequence a genome,” Haussler said. “At that point, most of the cost will be getting samples, managing the project, and handling data.”

By Randall Parker 2009 November 15 09:48 PM  Biotech Advance Rates
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High Selenium Boosts Blood Cholesterol?

Too much selenium probably boosts blood cholesterol.

A new study from the University of Warwick has discovered taking too much of the essential mineral selenium in your diet can increase your cholesterol by almost 10%.

Selenium is a trace essential mineral with anti-oxidant properties. The body naturally absorbs selenium from foods such as vegetables, meat and seafood. However, when the balance is altered and the body absorbs too much selenium, such as through taking selenium supplements, it can have adverse affects.  

A team led by Dr Saverio Stranges at the University's Warwick Medical School has found high levels of selenium are associated with increased cholesterol, which can cause heart disease. 

In a paper recently published in the Journal of Nutrition, the research team examined the association of plasma selenium concentrations (levels of selenium in the blood) with blood lipids (fats in the blood). 

The researchers found in those participants with higher plasma selenium (more than 1.20 µmol/L) there was an average total cholesterol level increase of 8% (0.39 mmol/L (i.e. 15.1 mg/dL). Researchers also noted a 10% increase in non-HDL cholesterol levels (lipoproteins within your total cholesterol that can help predict the risk of someone suffering a heart attack or chest pain). Also, of the participants with the highest selenium levels, 48.2% admitted they regularly took dietary supplements. 

It is not easy to choose an optimal diet.

This reminds me of a study that illustrates the potential for genetic testing to optimize diet choices (nutrigenomics): Whether selenium helps or hurts against prostate cancer risk depends on which genetic variant you have for the enzyme manganese superoxide dismutase (SOD2). So Brazil nuts probably cut prostate cancer risk in some while boosting risk for others.

Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute the University of California, San Francisco.

A higher risk of more aggressive prostate cancer was seen in men with a certain genetic variant found in about 75 percent of the prostate cancer patients in the study. In those subjects, having a high level of selenium in the blood was associated with a two-fold greater risk of poorer outcomes than men with the lowest amounts of selenium.

By contrast, the 25 percent of men with a different variant of the same gene and who had high selenium levels were at 40 percent lower risk of aggressive disease. The variants are slightly different forms of a gene that instructs cells to make manganese superoxide dismutase (SOD2), an enzyme that protects the body against harmful oxygen compounds.

You can imagine how two different studies on selenium and prostate cancer could come to opposite conclusions if their patient groups had different distributions of SOD2 variants.

If you are a guy and can find a genetic testing service that will test for SOD2 variants you could find out whether you should eat high selenium foods or avoid them. I wonder whether these SOD2 variants modify the risks for other diseases.

By Randall Parker 2009 November 15 09:39 PM  Aging Diet Heart Studies
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2009 November 14 Saturday
Drugs Better Than Diet For Cancer Prevention?

Gina Kolata, writing in the New York Times talks to a lot of top medical researchers and reports on cancer-preventing drugs that go unused and the many disappointing diet and vitamin interventions for cancer prevention.

Many Americans do not think twice about taking medicines to prevent heart disease and stroke. But cancer is different. Much of what Americans do in the name of warding off cancer has not been shown to matter, and some things are actually harmful. Yet the few medicines proved to deter cancer are widely ignored.

The article does an excellent job of reviewing assorted great hopes for reduced cancer risk via diet and vitamins and how many of these approaches failed in large scale intervention trials. Biogerontologist Aubrey de Grey probably doesn't find this surprising since he argues that if micronutrients could deliver large benefits we'd probably carry mutations to up their concentrations in our bodies. There is a counter evolutionary argument though: an antioxidant in higher concentrations might make us less fit in the short term and therefore would have been selected against.

I'm willing to use drugs to cut cancer risks. The drugs finasteride and dutasteride (both used to stop hair loss and treat swollen prostates) would eliminate over a quarter of all prostate cancer cases per year if taken long term to protect against prostate cancer.

A large and rigorous study found that a generic drug, finasteride, costing about $2 a day, could prevent as many as 50,000 cases each year. Another study found that finasteride’s close cousin, dutasteride, about $3.50 a day, has the same effect.

Did she say $2 per day? I used a drug price comparison web site and found Costco selling finasteride for $1.19 per 5 mg tablet in quantity 100. A 10 year supply would set you back about $4400. Having helped someone die from prostate cancer that seems like a very low price to pay to avoid a horrible end. Heck, you can do even cheaper abroad and this is a generic drug. You won't be ripping off intellectual property by buying abroad.

I'm already tempted to ask a doctor to prescribe finasteride or dutasteride. Preserve hair, avoid prostatic hyperplasia (where the prostate slows urine flow), and avoid prostate cancer. I mean, why not? The side effects are said to wear off after a year. Any readers taking it? One concern: what other effects come from lowering dihydrotestosterone? Does regular testosterone also rise as a result?

Tamoxifen cuts the risk of breast cancer in half. An osteoporosis drug, Evista, does the same thing with fewer risks.

Then, in 1999, he had a chance to do another breast cancer prevention trial, this time of an osteoporosis drug, raloxifene, or Evista, which did not have the cancer drug taint. It was to be compared with tamoxifen.

The $110 million study, involving 19,000 women, ended in 2006. The two drugs were found to be equally effective in preventing breast cancer, but with raloxifene there was no excess uterine cancer and the clotting risk was 30 percent less.

By Randall Parker 2009 November 14 02:44 PM  Aging Drugs
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Chocolate Lowers Stress Hormones

Eating chocolate might be good for people whose metabolisms show up as stressed in blood tests. Though I have to wonder whether attacking the underlying causes of high stress hormones would be more likely to deliver a real benefit.

The "chocolate cure" for emotional stress is getting new support from a clinical trial published online in ACS' Journal of Proteome Research. It found that eating about an ounce and a half of dark chocolate a day for two weeks reduced levels of stress hormones in the bodies of people feeling highly stressed. Everyone's favorite treat also partially corrected other stress-related biochemical imbalances.

One big problem with research on benefits of food on health: research that turns up a positive result is more likely to get published than research that turns up a negative result. So the body of all published research has a bias toward showing benefits.

Another big problem: short term effects do not always translate into long term reduction of illness or death. We end up with lots of promising studies that suggest dietary practices which are unproven or disproved many years later. Long term research takes too long and is so expensive that the number of hypotheses that get tested by long term research ends up being pretty short.

This study reminds me of a third problem: Some studies produce positive results because they happen to use experimental subjects most likely to benefit. Subsets of people who have more stress, a lousier diet to start with, or other problems are probably more likely to benefit from a diet change. Should you eat chocolate? The answer might depend on your levels of stress hormones.

In the study, scientists identified reductions in stress hormones and other stress-related biochemical changes in volunteers who rated themselves as highly stressed and ate dark chocolate for two weeks. "The study provides strong evidence that a daily consumption of 40 grams [1.4 ounces] during a period of 2 weeks is sufficient to modify the metabolism of healthy human volunteers," the scientists say

So does eating chocolate deliver a benefit? I'm still not convinced. But at least with chocolate my taste buds think I ought to lower my standard of evidence.

Update: Big population studies of diet and health will become a lot more useful once it becomes affordable to genetically sequence each person. My guess is that in some of the studies that find a benefit from a dietary practice for some of the people in that study their genomes were well matched to the dietary practice under study. The inability to control for genetic endowment is one of the causes of positive results that fail to generalize to hold up in other studies.

Similarly, if we all had implanted nanosensors reporting our metabolic condition our cell phones could query our nanosensors, report the results to a web site, and then get back recommendations for, say, exercise or chocolate or cruciferous vegetables.

By Randall Parker 2009 November 14 08:51 AM  Aging Diet Metabolism
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2009 November 12 Thursday
Younger Dryas Mini Ice Age Started Quickly

William Patterson of the University of Saskatchewan, says the Younger Dryas mini Ice Age came on in a matter of months.

JUST months - that's how long it took for Europe to be engulfed by an ice age. The scenario, which comes straight out of Hollywood blockbuster The Day After Tomorrow, was revealed by the most precise record of the climate from palaeohistory ever generated.

Around 12,800 years ago the northern hemisphere was hit by the Younger Dryas mini ice age, or "Big Freeze". It was triggered by the slowdown of the Gulf Stream, led to the decline of the Clovis culture in North America, and lasted around 1300 years.

Can our climate suddenly change drastically? Yes. We can't be assured of only slow gradual changes. Most of the time only slower changes happen. But rapid climate change is possible. For this reason I think we should develop the means to alter the climate on a global scale. We might some day need to reverse either a natural or human-made shift in climate.

The Younger Dryas also ended abruptly in 10 years.

Around 15,000 years ago, the Earth started warming abruptly after ~ 100,000 years of an "ice age"; this is known as a glacial termination. The large ice sheets, which covered significant parts of North America and Europe, began melting as a result. A climatic optimum known as the "Bölling-Allerød" was reached shortly thereafter, around 14,700 before present. However, starting at about 12,800 BP, the Earth returned very quickly into near glacial conditions (i.e. cold, dry and windy), and stayed there for about 1,200 years: this is known as the Younger Dryas (YD), since it is the most recent interval where a plant characteristic of cold climates, Dryas Octopetala, was found in Scandinavia.

The most spectacular aspect of the YD is that it ended extremely abruptly (around 11,600 years ago), and although the date cannot be known exactly, it is estimated from the annually-banded Greenland ice-core that the annual-mean temperature increased by as much as 10°C in 10 years.

That's an 18 F warming in ten years. Imagine your local climate changing that much that quickly.

Update: Some scientists think the Younger Dryas cooling was brought on by the bursting of the boundaries of a massive fresh water lake whose waters diluted the salt waters of the northern Atlantic Ocean and stopped the Gulf Stream. Therefore some argue we have no comparable plausible condition that can happen today to cause an equally sharp shift in climate. However, a massive upper atmosphere explosion of an asteroid is another possible explanation for the Younger Dryas. Such an asteroid collision with the Earth is certainly within the realm of the possible.

More generally, I think people have been lulled into complacency by a 20th century whose natural disasters were pretty mild. A century more like the 19th century is within the realm of the possible.

By Randall Parker 2009 November 12 10:04 PM  Climate Trends
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New Generation Of Elderly Suffer More Disabilities?

At least in the United States people in their 60s have more of several types of disabilities than the previous cohort of people in their 60s.

In a development that could have significant ramifications for the nation's health care system, Baby Boomers may well be entering their 60s suffering far more disabilities than their counterparts did in previous generations, according to a new UCLA study. The findings, researchers say, may be due in part to changing American demographics.

Have more obesity, less exercise, and other changes in diet and lifestyle begun to cut into life expectancies?

In the study, which will be published in the January 2010 issue of the American Journal of Public Health, researchers from the division of geriatrics at the David Geffen School of Medicine at UCLA found that the cohort of individuals between the ages of 60 and 69 exhibited increases in several types of disabilities over time. By contrast, those between the ages of 70 and 79 and those aged 80 and over saw no significant increases — and in some cases exhibited fewer disabilities than their previous cohorts.

While you can hear it widely said that medicine has made great advances those advances haven't been powerful enough to prevent other factors from making people less healthy. Now, some technological trends might well accelerate the rate of advance of medical technologies so much that rejuvenation therapies and other treatments will block and reverse the effects of dietary choices and poor lifestyle choices. But that hasn't happened yet. You really do have to take care of your body. You can't count on medicine to undo the damage caused by diet and lifestyle.

Update: WebMD has a more quantitative description of how much disability is increasing for people their 60s. The rises are pretty dramatic.

By Randall Parker 2009 November 12 09:02 PM  Aging Studies
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2009 November 11 Wednesday
Telomere Genes Linked To Longer Life

The tips of chromosomes are known as telomeres and they shrink in size every time a cell divides. Eventually the telomeres become short and interfere with cellular replication. This interference is probably an anti-cancer defense mechanism. At the same time, the shrinking of telomeres probably contributes to aging by reducing the ability of the body to make replacement cells to repair the body as we age. Well, old people with genetic variants that cause longer telomeres have a greater chance of living to age 100.

November 11, 2009 — (BRONX, NY) — A team led by researchers at Albert Einstein College of Medicine of Yeshiva University has found a clear link between living to 100 and inheriting a hyperactive version of an enzyme that rebuilds telomeres — the tip ends of chromosomes. The findings appear in the latest issue of the Proceedings of the National Academy of Sciences.

This is a surprising result because longer telomeres in old age might increase the risk of cancer.

If higher activity in telomere enzymes delays onset of cardiovascular diseases then this suggests that lack of ability to make replacement cells contributes to the development of cardiovascular disease.

More specifically, the researchers found that participants who have lived to a very old age have inherited mutant genes that make their telomerase-making system extra active and able to maintain telomere length more effectively. For the most part, these people were spared age-related diseases such as cardiovascular disease and diabetes, which cause most deaths among elderly people.

These results suggest to me that the ability to create safe youthful stem cells for implantation in our bodies might slow the aging process. I want lots of replacement cells with few harmful mutations and long telomeres.

By Randall Parker 2009 November 11 11:02 PM  Aging Mechanisms
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2009 November 10 Tuesday
Cars Join Into Virtual Trains In EU Research Project

Why use a human brain for each car on the road when a single human and some computers can do the driving for us?

Researchers in the European Union are using telematics to create “road trains” that join the benefits of carpooling with the freedom of driving alone.

The latest concept, part of the EU’s Safe Road Trains for the Environment initiative, groups cars with similar destinations into road trains over long stretches of highway. The lead vehicle will be driven by an experienced motorist — it may even be a bus that regularly travels the route — while the functions of each following vehicle will be automatically controlled and tethered to the actions of the lead car so that individual drivers can hammer out e-mails or eat breakfast.

Unfortunately I see big legal liability issues with any proposal to totally automate driving. What if the one driver makes a mistake? Or what if a car in the train suffers a mechanical failure? Or what if one of the car computers suffers a failure or a software bug? The technology could be much safer than conventional driving. But when the inevitable accident happens so do the lawsuits. Do lawsuits pose less of an obstacle in Europe?

The energy savings from this approach would be considerable because people wouldn't hit the brakes more than needed. Also, brakes would even last longer.

By Randall Parker 2009 November 10 11:25 PM  Robotics Cars
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California Droughts When Planet Warms?

Why worry about earthquakes when we can worry about massive droughts instead?

California experienced centuries-long droughts in the past 20,000 years that coincided with the thawing of ice caps in the Arctic, according to a new study by UC Davis doctoral student Jessica Oster and geology professor Isabel Montañez.

The finding, which comes from analyzing stalagmites from Moaning Cavern in the central Sierra Nevada, was published online Nov. 5 in the journal Earth and Planetary Science Letters.

Global warming gets a lot of attention due to the prospects of huge low lying areas getting submerged. But big changes in regional climate - whether human caused or not - seem much more interesting to me. Such changes could occur at any time.

Ratios of elements in stalagmites provide some indication of changing levels of precipitation.

The sometimes spectacular mineral formations in caves such as Moaning Cavern and Black Chasm build up over centuries as water drips from the cave roof. Those drops of water pick up trace chemicals in their path through air, soil and rocks, and deposit the chemicals in the stalagmite.

"They're like tree rings made out of rock," Montañez said. "These are the only climate records of this type for California for this period when past global warming was occurring."

Cooling periods make California wetter.

At the end of the last ice age about 15,000 years ago, climate records from Greenland show a warm period called the Bolling-Allerod period. Oster and Montanez's results show that at the same time, California became much drier. Episodes of relative cooling in the Arctic records, including the Younger Dryas period 13,000 years ago, were accompanied by wetter periods in California.

During the Medieval Warm Period what is now the western United States had an epic drought from 900 to 1300 AD. Imagine such a drought started in the 21st century. How to prevent large areas from becoming mostly uninhabitable due to lack of water? Could we build enough nuclear power plants near oceans to desalinate and pump water a thousand miles inland? What would be the cost?

Alternatively, could windmills in oceans upwind of continents be used to pump more moisture into the air before winds blow over continents? Picture a future where nanotechnology makes manufacturing cheap. This could become an affordable way to bring water inland.

By Randall Parker 2009 November 10 11:06 PM  Climate Trends
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Great Pacific Garbage Patch Keeps Getting Bigger

We are letting far too much plastic end up in the oceans.

ABOARD THE ALGUITA, 1,000 miles northeast of Hawaii — In this remote patch of the Pacific Ocean, hundreds of miles from any national boundary, the detritus of human life is collecting in a swirling current so large that it defies precise measurement.

In 1804, a little over 200 years ago, the planet had a human population of 1 billion people. Back then the oceans seemed immense and beyond the capacity of humans to change. Yet by 1850 whale hunting peaked due to over harvesting and we've since drastically drawn down the stocks of other ocean-going creatures such as cod and salmon.

Now Earth has 6.8 billion people and some demographers predict 9 billion by 2040. At the same time, China and India are industrializing along with the nations of southeast Asia. The capacity to make trash is soaring. Our oceans will suffer much worse from this. Just one of the ocean's big garbage patches is doubling in size every decade.

Light bulbs, bottle caps, toothbrushes, Popsicle sticks and tiny pieces of plastic, each the size of a grain of rice, inhabit the Pacific garbage patch, an area of widely dispersed trash that doubles in size every decade and is now believed to be roughly twice the size of Texas.

I fear Peak Oil will do more to cut back on ocean plastic pollution than anything the governments of the world decide to do to cut plastics pollution. Currently human population growth, industrialization, and rising consumption count for more than efforts to clean up the environment.

Most of the plastic is broken up below the surface.

Charles Moore, an American oceanographer who discovered the "Great Pacific Garbage Patch" or "trash vortex", believes that about 100 million tons of flotsam are circulating in the region. Marcus Eriksen, a research director of the US-based Algalita Marine Research Foundation, which Mr Moore founded, said yesterday: "The original idea that people had was that it was an island of plastic garbage that you could almost walk on. It is not quite like that. It is almost like a plastic soup. It is endless for an area that is maybe twice the size as continental United States."

In some parts of the ocean there's more plastic than plankton.

Mr Moore found bottle caps, plastic bags and polystyrene floating with tiny plastic chips. Worn down by sunlight and waves, discarded plastic disintegrates into smaller pieces. Suspended under the surface, these tiny fragments are invisible to ships and satellites trying to map the plastic continent, but in subsequent trawls Mr Moore discovered that the chips outnumbered plankton by six to one.

Birds eat plastic scraps and it ends up killing them.

We need fewer people and people need to wake up to the scale of human interventions in the environment.

By Randall Parker 2009 November 10 10:44 PM  Pollution Trends
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Receptor Controls Long Term Memory Formation

A drug that turns off the nogo receptor 1 blocks long term memory formation in mice. Imagine a drug that did the same thing in humans. It would have all sorts of uses and abuses.

Researchers at Karolinska Institutet have discovered a mechanism that controls the brain's ability to create lasting memories. In experiments on genetically manipulated mice, they were able to switch on and off the animals' ability to form lasting memories by adding a substance to their drinking water. The findings, which are published in the scientific journal PNAS, are of potential significance to the future treatment of Alzheimer's and stroke.

It seems likely that drugs which block long term memory formation will be found. Criminals could use these drugs for all sorts of purposes. Commit a crime, force every witness (or victim) to down a drug (preferably liquid so they can't throw up to get it out of them), and then leave.

But then James Bond would get a gene therapy treatment that renders his nogo receptor 1 immune to the known memory blocker drugs.

A research team at Karolinska Institutet has now discovered that signalling via a receptor molecule called nogo receptor 1 (NgR1) in the nerve membrane plays a key part in this process. When nerve cells are activated, the gene for NgR1 is switched off, and the team suspected that this inactivation might be important in the creation of long-term memories. To test this hypothesis they created mice with an extra NgR1 gene that could remain active even when the normal NgR1 was switched off.

Technology enables competitions, struggles, and fights to take place at a higher level. In the long term will technology make society more or less stable?

By Randall Parker 2009 November 10 06:40 AM  Brain Memory
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2009 November 09 Monday
Persuasive Technology

An article in New Scientist explores how user interface researchers are developing ways to better persuade people to make choices that assorted organizations want them to make.

Researchers at Eindhoven University of Technology in the Netherlands are using iCat, a robotic cat made by Philips, to advise on energy use. It talks and can move its lips, eyelashes and eyebrows.

Concerns from an early era about the ability of Madison Avenue advertising agencies to brainwash humans with TV ads seem quaint compared to what high resolution UIs and eventually artificially intelligent robots will do to persuade us.

Cuteness can persuade.

One experiment showed that when programming a washing machine, people were more inclined to follow energy consumption advice about different cycles when it came from iCat rather than graphs and numbers. That suggests the savings which simple awareness can provoke can be magnified by using more "social" mechanisms to deliver advice.

I am reminded of the web site cuteoverload.com which really does deliver on its name. That sort of high dose cuteness could really be automated to barrage humans with cute images aimed at persuading. Imagine a really fast computer capable of making very high resolution simulations of kitties that do things that an appliance's designers want you to do.

A refrigerator might reward you with cute images for eating vegetables rather than high calorie foods. Or a car could deluge you with cute kitty images because you went easy on the throttle. Already the Ford Fusion Hybrid dashboard grows green leaves in proportion to how easy you go on the gas pedal.

I expect device developers to take all the persuasion research and embed persuasive techniques from that research into products. We'll be far more persuaded in the future. Will we develop resistance to this more sophisticated, automated, and pervasive persuasion? Or will we be happier knowing we are making decisions designed to make us feel rewarded for choosing them?

By Randall Parker 2009 November 09 10:06 PM  Brain Free Will
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2009 November 08 Sunday
Widespread Chronic Pain

John Tierney of the New York Times draws attention to the high prevalence of chronic pain.

Chronic pain affects more than 70 million Americans, which makes it more widespread than heart disease, cancer and diabetes combined. It costs the economy more than $100 billion per year. So why don’t more doctors and researchers take it seriously?

Think about that 70 million number. It is worse than it looks. At about 23% of the population that means almost 1 in 4 people live in chronic pain. But since the injuries and illnesses that cause chronic pain accumulate with age your own odds of eventually living in chronic pain are much higher than 1 in 4. The lesson here: human bodily aging is not dignified, it is not beautiful, and it is painful.

That is the challenge raised by a new report from the Mayday Fund, a nonprofit group that studies pain treatment. The report, which been endorsed by an array of medical groups, advocates a revolution in the training of doctors, the financing of research and the education of law-enforcement officials.

I advocate the faster development of rejuvenation therapies so that we can repair the damage that causes chronic pain. I also advocate more careful living. You are just one injury away from suffering the rest of your life.

By Randall Parker 2009 November 08 09:46 PM  Aging Population Problems
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Too Much Time Indoors Causes Myopia?

In sometimes subtle ways we are creating a civilization that is incompatible with some of our genetic inheritance. Some researchers working in Australia and Singapore were able too show that children who spend less time outdoors get myopia at higher rates.

The team looked only at children of Chinese ethnicity, to rule out genetic differences between races as an explanation for higher myopia rates in certain countries.

The result? On average the children in Sydney spent nearly 14 hours per week outside, and only 3 per cent developed myopia. In contrast, the children in Singapore spent just 3 hours outside, and 30 per cent developed myopia. Once again, close work had a minimal influence; the Australian children actually spent more time reading and in front of their computers than the Singaporeans (Archives of Ophthalmolology, vol 126, p 527).

Possibly the light hitting the eyeballs regulates their growth and insufficient light during development causes the eyeballs to grow incorrectly. The article describes the results of other research on causes of myopia. Click through if you have an interest.

Singapore with its dense population and high rise living strikes me as the sort of place where humans experience an environment far from our ancestral environments. Kids can't easily play outside when they live in a high rise. Cities really aren't good for raising children. By contrast, I feel fortunate that where I grew up I walked out the door and I was on a big plot of land bordering a forest and farm land. I could get thoroughly dirty (an opportunity rarely missed). The dirt probably helped my immune system develop from all the microbes it came into contact with. Plus, summers were spent outside for very long hours. Lots of vitamin D and light hitting my eyeballs.

By Randall Parker 2009 November 08 09:11 PM  Human Unnatural Environment
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2009 November 07 Saturday
Chevy Volt Batteries In Cold Weather

A Fortune Magazine article by Alex Taylor points to qualifiers on claims of the performance of the forthcoming Chevy Volt pluggable hybrid electric vehicle (PHEV). Read the whole article. But I found the part about batteries most interesting.

That's not all. Also under scrutiny is GM's oft-repeated assertion that the Volt will have an all-electric range of 40 miles. Critics point out that the car needs ideal conditions to do that.

For one thing, the 40-mile range depends on ambient temperatures of 60 degrees to 65 degrees. When the temperature drops below 60, the batteries become less efficient. And if it gets hotter than 65, the air conditioner can impose an additional load on the Volt's batteries. Either way, the range diminishes.

But no quantitative information about how range goes down with dropping temperature. A question for any reader who knows a lot about battery performance: How much does battery performance decline with temperature? What sort of range can a guy in Wisconsin or upstate Minnesota expect in January with a Volt that can go 40 miles in late spring?

Also, how does battery performance fare in the Mojave Desert in July?

Also, does the extent of battery performance decline with temperature vary by battery technology? How do lead acid, NiMH, and Lithium ion batteries compare? Do some lithium chemistries to better than others in cold weather?

If battery range drops only to, say, 30 miles then that doesn't seem like a show-stopper. The majority of the American commuting public goes less than 30 miles round trip to work every day.

Update: In the comments "bbm" reminds me that GM has built the Volt to have a substantial margin its battery capacity. Of the 16 kwh of battery capacity the Volt needs only 8 kwh to go 40 miles. GM does not want to discharge more than 70%. So effectively there's a 2.4 kwh reserve available for colder weather. So the Volt might start out with 10.4 kwh available in mild weather.

Also in the comments agesilaus points to a research paper about Li ion battery performance in cold weather. At least with the Li ion battery used as an example the battery lost 15% going down to 0 C (32 F) from a mild temperature. Well, a 15% loss off of 10.4 kwh would still leave the volt above 8 kwh. at -10 C (14 F) the Volt would lose another 10% and might be slightly below 40 mile range. Though I wonder how much heater power would be needed to stay warm with an outside air temperature that cold.

By Randall Parker 2009 November 07 07:29 PM  Energy Electric Cars
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Silicon Nanowires Boost Lithium Battery Energy Density

Yet another electric battery start-up touting a big advance in battery technology.

A start-up based in Menlo Park, CA, plans to sell a new type of anode for lithium-ion batteries that, the company says, will let electric vehicles travel farther and mobile devices last longer without a recharge. Amprius' lithium-ion anodes are made of silicon nanowires, which can store 10 times more charge than graphite, the material used for today's lithium-ion battery anodes. According to the company, electric vehicles that run 200 miles between charges could go 380 miles on its batteries, and laptops that have four hours of run time could last for seven hours between charges.

All of the start-up activity in battery technology makes me optimistic that we can shift away from liquid fuels for most ground transportation uses. But will the battery tech come soon enough for Peak Oil? The answer to that question is still not clear.

By Randall Parker 2009 November 07 08:27 AM  Energy Batteries
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2009 November 06 Friday
Climate Engineering Reaches Mainstream Debate

A US Congressional committee held hearings on engineered approaches to cooling the planet.

In addition to multiple articles and books in the popular media, the United Kingdom's Royal Society, the authoritative national academy of science there, issued an in-depth review of geoengineering and President Obama's science advisor, John Holdren, has repeatedly stated that geoengineering must be on the table as a possible approach to addressing climate change.

Makes sense to debate and study the option decades before it might become necessary to use it.

Yesterday, the House of Representatives' Committee on Science and Technology held a hearing that its chairman, Bart Gordan (D-TN), said was, "the first time that a congressional committee has undertaken a serious review of proposals for climate engineering."

Gordan was quick to say that this doesn't mean he supported geoengineering, and that the consensus at the hearing seemed to be that no one should deploy geoengineering until we've done a lot more research.

I've been writing about climate engineering for years. My own take: Cooling the planet with aerosols or a huge array of reflective satellites might some day deliver a net benefit. But climate engineering is problematic for a few reasons:

  • Cooling the planet doesn't reverse the effects of ocean acidification caused by more carbon dioxide dissolving into the ocean.
  • The cooling method would likely change rain patterns as compared to the same level of coolness as a result of reduced CO2 in the atmosphere. So some large populations could come out net losers.
  • The effects of any cooling method would not all be foreseeable in advance or even accurately attributable once they happened. Did the torrential rains or drought in some country happen due to the cooling or would they have been even worse without the cooling?
  • Some of the perceived costs and benefits would be highly subjective to different people in the same area. Even farmers of different kinds of crops would see the same changes in climate as delivering different costs and benefits.

So one needs to be looking at a pretty dire and certain future (e.g. big sea level rises flooding out southern Florida, New York City, Bangladesh, and London) before launching into such a drastic undertaking.

On the other hand, it is possible to wade into climate engineering with some measures that would be widely seen as quite innocuous. For example, building roofs, which are human constructions in the first place could all be painted white to delay global warming. US Energy Secretary Steven Chu sees white roofs as fairly benign. One could argue that white roofs and white roads would counteract changes in albedo that we caused in the first place by constructing dark roofs and black asphalt roads. So the argument will be made that roof painting represents a restoration of previous natural albedo.

My guess is we'll see policies put into place to do mild forms of climate engineering and once started down that path if the world really starts to heat up bigger and bigger interventions will get implemented.

By Randall Parker 2009 November 06 05:26 PM  Climate Engineering
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2009 November 05 Thursday
Genome Sequencing Cost Drops Below $5000

Futuristic speculative questions sometimes become present day practical questions. Have you asked yourself what price you'd be willing to pay to get your genome fully sequenced?

Complete Genomics, a start-up based in Mountain View, CA, has again lowered the stick in the financial limbo dance of human genome sequencing, announcing in the journal Science that it has sequenced three human genomes for an average cost of $4,400. The most recently sequenced genome--which happens to be that of genomics pioneer George Church--cost just $1,500 in chemicals, the cheapest published yet.

This doesn't mean you can get your genome sequenced for $4400. They also had labor, equipment, and lab space costs as well as data post-processing costs. But the overall costs are still very low.

Their accuracy rate exceeds that of previous efforts at complete genome sequencing.

In order to estimate their error rate, the researchers tested 291 random novel non-synonymous variants by targeted sequencing in sample NA07022. Based on the results, they calculated an error rate of about one in 100,000 bases, which the company claims "exceeds the accuracy rate achieved in other published complete genome sequences."

While the price keeps dropping the practical value of a person's genetic sequence is rising with more discoveries about what all the genetic differences mean. The rapid descent in genome sequencing costs has advanced so far that lower prices matter less than what you can do with the information. At this point the bigger improvements to the value equation for getting a full genome sequencing will come from scientific discoveries about what all the genetic variations mean.

The lower prices will lead to a flood of genetic data that will lead to discoveries about what the data means. In a few years knowing your full genetic sequence will become quite useful.

Recently Pauline C. Ng, Sarah S. Murray, Samuel Levy and J. Craig Venter sent genetic samples to genetic testing services Navigenics and 23andme and wrote a paper in nature comparing the results. The two companies were pretty accurate in their testing. But their interpretations of the results differed and were speculative. Click thru and read the details. We do not yet know enough about the real significance of the vast bulk of the genetic differences.

By Randall Parker 2009 November 05 10:36 PM  Biotech Advance Rates
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Nitrogen Cycle Added To Climate Model

What is missing from climate models?

OAK RIDGE, Tenn., Oct. 9, 2009 -- For the first time, climate scientists from across the country have successfully incorporated the nitrogen cycle into global simulations for climate change, questioning previous assumptions regarding carbon feedback and potentially helping to refine model forecasts about global warming.

My own reaction: amazement. We are in the year 2009 and only now the nitrogen cycle gets added to climate models? What other important factors are not yet in climate models? Does anyone know? I'm looking for a knowledgeable reply, not a rant. What is the state of climate models? What are the prospects for more accurate models 5, 10, 20 years from now?

These scientists expect more rapid climate change as a result of adding the nitrogen cycle.

The results of the experiment at the Department of Energy's Oak Ridge National Laboratory and at the National Center for Atmospheric Research are published in the current issue of Biogeosciences. They illustrate the complexity of climate modeling by demonstrating how natural processes still have a strong effect on the carbon cycle and climate simulations. In this case, scientists found that the rate of climate change over the next century could be higher than previously anticipated when the requirement of plant nutrients are included in the climate model.

ORNL's Peter Thornton, lead author of the paper, describes the inclusion of these processes as a necessary step to improve the accuracy of climate change assessments.

You might think climate models can be really accurate even without the nitrogen cycle. But recall a recent post I did about biofuels boosting nitrous oxide emissions and thereby causing big warming effects. Where the nitrogen goes and in what form is very important for the climate.

MBL, WOODS HOLE, MA—A report examining the impact of a global biofuels program on greenhouse gas emissions during the 21st century has found that carbon loss stemming from the displacement of food crops and pastures for biofuels crops may be twice as much as the CO2 emissions from land dedicated to biofuels production. The study, led by Marine Biological Laboratory (MBL) senior scientist Jerry Melillo, also predicts that increased fertilizer use for biofuels production will cause nitrous oxide emissions (N2O) to become more important than carbon losses, in terms of warming potential, by the end of the century.

Fertilizer usage is going to rise anyway due to increasing human population and industrialization. So how much will nitrous oxide emissions increase in the 21st century? Also, how much will fertilizer run-off and phytoplankton blooms increase? Will the Antarctic continent become livable as a result? Always look on the bright side of life.

By Randall Parker 2009 November 05 08:10 PM  Climate Trends
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2009 November 04 Wednesday
Policy Decisions Slow H1N1 Vaccine Production

Why is H1N1 influenza vaccine coming out so slowly in the United States? Dr. Scott Gottlieb, a former FDA deputy commissioner, says a few policy decisions slow the production of vaccine.

Why do adjuvants matter? An adjuvanted H1N1 vaccine being used in Europe contains 3.75 micrograms of vaccine stock. The same vaccine in the U.S., without the adjuvant, requires 15 micrograms of vaccine for equal potency. If we used adjuvants, we could have had four times the number of shots with the same raw material.

Our regulators are more risk-averse. If a much more lethal pandemic flu strain popped up would the regulators continue to be so conservative?

We need to move beyond the use of chicken eggs to produce virus proteins for vaccine. The much more rapid and scalable approach using mammalian cells is already in use in Europe, not so in the US. Again, regulatory conservatism makes a difference.

The third policy decision was to stick for too long with a proven, but slow process for making flu shots that uses chicken eggs to grow the raw vaccine material. Shots can be made much faster using mammalian cells to grow vaccine, and this process is already being used in Europe. The cell-based vaccines are unlikely to be approved in the U.S. Our precaution when it comes to vaccines means we don't easily embrace novel technologies, even if the Europeans would part with some of their limited supply.

Luckily H1N1 isn't lethal to all that many people. Tens of thousands might die. But a repeat of 1918 levels of lethality would require a far far less conservative approach to vaccine approvals. Would the US government make the needed changes in regulatory policy when tens of millions of lives are at stake?

Forget global free trade when lives are at stake. Where the vaccine manufacturing plants are located also matters.

In 2004, only two companies were licensed to sell flu vaccine in the United States; now there are five, but only one, Sanofi-Pasteur, has a domestic plant. The others — GlaxoSmithKline, Novartis, CSL Ltd. and Medimmune — use plants in England, Germany and Australia.

The drawback of relying on foreign plants was made clear recently when the Australian government pressured CSL to keep its vaccine at home instead of fulfilling its contract for 36 million doses of swine flu vaccine for the United States.

H1N1 vaccine production is late.

Frieden said the CDC had a cumulative 26.6 million doses of vaccine available -- far short of the 40 to 80 million that had been forecast for the end of October.

My advice: take vitamin D and clean your hands more often.

By Randall Parker 2009 November 04 11:07 PM  Pandemic Vaccines
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Ionic Liquid Battery To Beat Lithium Ion?

Yet another claimant to the future best battery throne.

A spinoff from Arizona State University says it can develop a metal-air battery that dramatically outperforms the best lithium-ion batteries on the market, and now it has the funding it needs to prove it.

The amount of battery innovation seems to have really picked up in recent years. Clamor for better batteries for cell phones and laptop computers provides big demand today. At the same time, a big push by car companies to develop more hybrids and pluggable hybrids provides assurances that a far larger source of demand is building. Government policy provides incentives for the latter as well as money for research. Hence lots of start-ups.

An order of magnitude higher energy density? That'd be a game changer if it can work well in real world use.

The U.S. Department of Energy last week awarded a $5.13-million research grant to Scottsdale, AZ-based Fluidic Energy toward development of a metal-air battery that relies on ionic liquids, instead of an aqueous solution, as its electrolyte.

The company aims to build a Metal-Air Ionic Liquid battery that has up to 11 times the energy density of the top lithium-ion technologies for less than one-third the cost.

With great batteries the looming threat of Peak Oil becomes a lot less menacing. 95% of all transportation energy comes in the form of liquid fossil fuels and transportation is the sector most vulnerable to declining oil production. Electric power for cars and trucks would let keep flowing the goods and people even as less oil flows.

Update: Here's an ultracapacitor start-up.

An MIT spinoff just getting off the ground received a huge helping hand from the U.S. Department of Energy on Monday. FastCAP Systems, of Cambridge, MA, received a two-and-a-half-year, $5.35 million grant in the first round of funding ever issued by the new Advanced Research Projects Agency-Energy (ARPA-E). The company aims to commercialize a nanotube-enhanced ultracapacitor, an energy storage device that could greatly reduce the cost of hybrid and electric vehicles and of fast-responding grid-scale energy storage, making it easier to integrate renewable energy sources such as solar and wind-based power.

Capacitors can deliver current faster than batteries and stand between the batteries and the engine and regenerative braking system.

By Randall Parker 2009 November 04 10:38 PM  Energy Biomass
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2009 November 03 Tuesday
Judge Rules Genetic Mutation Partial Defense Against Murder

A murderer in Italy got a lighter sentence due to a judge's view that the murderer had a genetically impaired ability to resist violent impulses.

A judge's decision to reduce a killer's sentence because he has genetic mutations linked to violence raises a thorny question – can your genes ever absolve you of responsibility for a particular act?

Regards the idea of genes absolving someone of responsibility: If they do then I think the genes reduce a person's rights at the same time. If a person has genes that compel him to violate the rights of others then that person lacks attributes needed to make that person into a full rights-possessing being.

In my view human rights do not come about as a result of our having spirits or souls. We do not have rights because we all just up and decided we had rights either. A rights-based system requires that the rights-possessing conscious intelligent beings have the capacity to act as moral agents. Someone who is compelled to murder or steal lacks attributes needed in a rights-possessing being. The ability to reason is not by itself sufficient to make a being have the attributes needed to possess rights.

Cutting the sentence of a genetically driven killer by a year is nuts. If someone really can't prevent themselves from carrying out murder then that person needs to be permanently removed from civilized society.

In 2007, Abdelmalek Bayout admitted to stabbing and killing a man and received a sentenced of 9 years and 2 months. Last week, Nature reported that Pier Valerio Reinotti, an appeal court judge in Trieste, Italy, cut Bayout's sentence by a year after finding out he has gene variants linked to aggression. Leaving aside the question of whether this link is well enough understood to justify Reinotti's decision, should genes ever be considered a legitimate defence?

If a lion or tiger kills a human we do not consider it a murderer because we do not view lions and tigers and bears (oh my) as moral agents. I expect genetic research and neuroscience to continue to produce results that leave less room for free will as the agent for decision-making in humans. To the extent that compulsions and drives pull people toward engaging in behaviors those people become less rights-deserving.

By Randall Parker 2009 November 03 10:25 PM  Bioethics Free Will
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Lowering Cholesterol Cuts Cancer Risk?

Will cutting your cholesterol lower your cancer risk?

PHILADELPHIA – A pair of studies in Cancer Epidemiology, Biomarkers & Prevention, lay to rest the decades-long concern that lower total cholesterol may lead to cancer, and in fact lower cholesterol may reduce the risk of high-grade prostate cancer.

Demetrius Albanes, M.D., a senior investigator at the National Cancer Institute, said early studies suggested that low cholesterol could increase the risk of certain types of cancer.

"Our study affirms that lower total cholesterol may be caused by undiagnosed cancer. In terms of public health message, we found that higher levels of 'good cholesterol' (HDL) seem to be protective for all cancers, which is in line with recommendations for cardiovascular health," said Albanes.

Lowering cholesterol cuts cancer risk 15% overall.

In Platz's study, cholesterol levels had no significant effect on the entire spectrum of prostate cancer incidence, only those that were high-grade, she says.

Platz cautions that, while the group took into account factors that could bias the results, such as smoking history, weight, family history of prostate cancer, and dietary cholesterol, other things could have affected their results. One example is whether men in the study were taking cholesterol-lowering drugs at the time of the blood collections, a data point the researchers expect to analyze soon.

Results of the current study are expected to be published online Nov. 3 in the journal Cancer Epidemiology, Biomarkers & Prevention. Also in the journal is an accompanying paper from the National Cancer Institute showing that lower cholesterol in men conferred a 15 percent decrease in overall cancer cases.

If you want to lower your cholesterol go paleo and make like an ape man.

By Randall Parker 2009 November 03 10:10 PM  Aging Diet Cancer Studies
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Full Fat Milk Drinking Children Weigh Less

Could the conventional mainstream wisdom about diet (more carbo, less fat) be, like, totally wrong? Researchers at the Sahlgrenska Academy in Sweden find that children who drink full-fat milk have lower body mass index.

Eight-year-old children who drink full-fat milk every day have a lower BMI than those who seldom drink milk. This is not the case for children who often drink medium-fat or low-fat milk. This is one conclusion of a thesis presented at the Sahlgrenska Academy.

The study showed that children who drink full-fat milk every day weigh on average just over 4 kg less.

"This is an interesting observation, but we don't know why it is so. It may be the case that children who drink full-fat milk tend also to eat other things that affect their weight. Another possible explanation is that children who do not drink full-fat milk drink more soft drinks instead", says dietician Susanne Eriksson, author of the thesis.

Better deep fat than the high fructose corn syrup found in soda.

The scientists also discovered a difference between overweight children who drink full-fat milk every day and those who do not. Children who often drink milk with a fat content of 3% are less overweight. The thesis shows also that the children eat more saturated fat than recommended, but those children who have a high intake of fat have a lower BMI than the children with a lower intake of fat.

For some children there is no deep fat. The children of Woody Allen's futuristic Sleeper knew (or will know) better.

By Randall Parker 2009 November 03 05:02 PM  Aging Diet Weight Studies
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2009 November 02 Monday
Metabolic Syndrome Is A Killer

High cholesterol isn't as dangerous as a combination of obesity, high blood pressure, and high blood sugar (insulin resistant diabetes).

The team, led by Assistant Clinical Professor of Public Health at Warwick Medical School Dr Oscar Franco, has discovered that simultaneously having obesity, high blood pressure and high blood sugar are the most dangerous combination of health factors when developing metabolic syndrome.

How dangerous are these factors? Way more.

In his study, published in the American Heart Association journal Circulation, Dr Franco has identified the most dangerous combination of these conditions to be central obesity, high blood pressure and high blood sugar. People who have all three of these conditions are twice as likely to have a heart attack and three times more likely to die earlier than the general population.

His team looked at 3,078 people to track the prevalence and progress of Metabolic Syndrome as part of the Framingham Offspring Study.

What to do about it? Exercise and a better diet of course.

Intensive lifestyle changes aimed at modest weight loss reduced the rate of developing type 2 diabetes by 34 percent over 10 years in people at high risk for the disease.

My own advice: eat lots and lots of vegetables, drug no sweet drinks, and avoid food that has high fructose corn syrup or sugar in it. Start reading labels.

I suspect the benefit of frequent interaction with health-care professionals mainly came in the form of repetitive encouragement to lose weight and eat better and less food.

The DPP results showed that intensive lifestyle changes, including exercise, reducing calories and fat intake and frequent interaction with health-care professionals, reduced the development of type 2 diabetes by 58 percent after three years. Those assigned to two daily doses of metformin but no lifestyle changes reduced the development of the disease by 31 percent over the same period.

Of course you could just take the drug. It'll only deliver about half the benefit but with much less effort.

By Randall Parker 2009 November 02 10:40 PM  Aging Diet Metabolism
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Low Exercise Not Cause Of Adolescent Obesity Spike?

This result strengthens my suspicion that high fructose corn syrup is to blame for the obesity epidemic.

Decreased physical activity may have little to do with the recent spike in obesity rates among U.S. adolescents, according to researchers at the Johns Hopkins Bloomberg School of Public Health. Prompted by growing concern that the increase was due to decreased physical activity associated with increased TV viewing time and other sedentary behaviors, researchers examined the patterns and time trends in physical activity and sedentary behaviors among U.S. adolescents based on nationally representative data collected since 1991. The review found signs indicating that the physical activity among adolescents increased while TV viewing decreased in recent years. The results are featured in the October 30 online issue of Obesity Reviews.

"Although only one third of U.S. adolescents met the recommended levels of physical activity, there is no clear evidence they had become less active over the past decade while the prevalence of obesity continued to rise," said Youfa Wang, MD, PhD, MS, senior author of the study and an associate professor with the Bloomberg School's Center for Human Nutrition and the Department of International Health. "During the recent decade, U.S. adolescents had greater access to TV, but significantly fewer of them watched TV for three or more hours per day. In addition, daily physical education attendance rates improved along with the use of physical education class in engaging in physical activity. However, there are considerable differences in the patterns by age, sex and ethnicity."

If less exercise isn't the cause of the obesity epidemic then what is? Some people say it is cheaper food. I'm skeptical. Lots of middle class kids had all the food they could eat in the 1960s. Refrigerators were full. Why did the obesity epidemic come later?

By Randall Parker 2009 November 02 10:20 PM  Aging Exercise Studies
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Small Walkable And Breathable Neighborhood Overlap

A study in Vancouver BC finds that very few people live in ideal neighborhoods that feature both high walkability and clean air.

A new study compares neighborhoods' walkability (degree of ease for walking) with local levels of air pollution and finds that some neighborhoods might be good for walking, but have poor air quality. Researchers involved in the study include University of Minnesota faculty member Julian Marshall and University of British Columbia faculty Michael Brauer and Lawrence Frank.

I find these results to be important reminders on the value of electric vehicles. Cities and suburbs would both become better for our health if more vehicles were battery powered.

If we had finer granularity maps of pollution I bet it would change housing prices. Just what is the health cost of living 50 yards, 100 yards, or 200 yards from a busy freeway? Also, just driving to work during the busy part of the day is bad because you are right in the lanes breathing soot.

The research team found that, on average, neighborhoods downtown are more walkable and have high levels of some pollutants, while suburban locations are less walkable and have high levels of different pollutants. Neighborhoods that fare well for pollution and walkability tend to be a few miles away from the downtown area. These "win-win" urban residential neighborhoods--which avoid the downtown and the suburban air pollution plus exhibit good walkability--are rare, containing only about two percent of the population studied. Census data indicate that these neighborhoods are relatively high-income, suggesting that they are desirable places to live. Neighborhoods that fare poorly for both pollution and walkability tend to be in the suburbs and are generally middle-income.

I just hate it when an old smelly diesel truck drives by when I'm out for a walk. I see them coming and alter my path to reduce the fume exposure. Sometimes I suck in a big breath just before they pass so I can get upwind of the exhaust before I breathe again.

"The finding that nitric oxide concentrations are highest downtown, while ozone concentrations are highest in the suburbs, is not surprising," said Marshall. "Motor vehicle exhaust is most concentrated downtown, leading to the high nitric oxide concentrations downtown. In contrast, ozone takes time to form. Air masses have moved away from downtown--often, to suburban areas--by the time ozone concentrations reach their highest levels. Thus, reductions in vehicle emissions can benefit people who live near high-traffic areas and also people living in less dense areas."

I think more people who live in polluted areas ought to get HEPA filters. Also, again, this report is an argument for electric cars and trucks.

By Randall Parker 2009 November 02 10:15 PM  Pollution Air
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80 Min Exercise Per Week Prevents Visceral Weight Gain

Fat around your internal organs is thought to be a much bigger risk factor for heart disease than fat near the surface of the skin. Well, if you go on a diet, exercise, get your weight down, and then eventually go off the diet continued exercise will prevent the resulting weight gain from happening where the risk factor is greatest.

BIRMINGHAM, Ala. - A study conducted by exercise physiologists in the University of Alabama at Birmingham (UAB) Department of Human Studies finds that as little as 80 minutes a week of aerobic or resistance training helps not only to prevent weight gain, but also to inhibit a regain of harmful visceral fat one year after weight loss.

The study was published online Oct. 8 and will appear in a future print edition of the journal Obesity.

Unlike subcutaneous fat that lies just under the skin and is noticeable, visceral fat lies in the abdominal cavity under the abdominal muscle. Visceral fat is more dangerous than subcutaneous fat because it often surrounds vital organs. The more visceral fat one has, the greater is the chance of developing Type 2 diabetes and heart disease.

80 minutes per week of either aerobic or resistance training prevents any fat weight gain around the internal organs. This is good news.

"What we found was that those who continued exercising, despite modest weight regains, regained zero percent visceral fat a year after they lost the weight," Hunter said. "But those who stopped exercising, and those who weren't put on any exercise regimen at all, averaged about a 33 percent increase in visceral fat.

It takes at least an hour a day of exercise to prevent weight gain. But 80 minutes per week to prevent the harmful form of weight gain is only 19% of the hour per day amount. So this is a lot easier.

By Randall Parker 2009 November 02 06:32 AM  Aging Diet Heart Studies
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2009 November 01 Sunday
Facial Proportions Show Aggressiveness

You've heard that we shouldn't judge people by their appearances and that appearances are only skin deep. Well no. People can predict the aggressiveness of other people after viewing their facial pictures for less than a second.

Angry words and gestures are not the only way to get a sense of how temperamental a person is. According to new findings in Psychological Science, a journal of the Association for Psychological Science, a quick glance at someone's facial structure may be enough for us to predict their tendency towards aggression.

Facial width-to-height ratio (WHR) is determined by measuring the distance between the right and left cheeks and the distance from the upper lip to the mid-brow. During childhood, boys and girls have similar facial structures, but during puberty, males develop a greater WHR than females. Previous research has suggested that males with a larger WHR act more aggressively than those with a smaller WHR. For example, studies have shown that hockey players with greater WHR earn more penalty minutes per game than players with lower WHR.

Psychologists Justin M. Carré, Cheryl M. McCormick, and Catherine J. Mondloch of Brock University conducted an experiment to see if it is possible to predict another person's propensity for aggressive behavior simply by looking at their photograph. Volunteers viewed photographs of faces of men for whom aggressive behavior was previously assessed in the lab. The volunteers rated how aggressive they thought each person was on a scale of one to seven after viewing each face for either 2000 milliseconds or 39 milliseconds.

We have the innate ability to read faces and know things about a person's personality.

The photographs were very revealing: Volunteers' estimates of aggression correlated highly with the actual aggressive behavior of the faces viewed, even if they saw the picture for only 39 milliseconds. Even more interestingly, the volunteers' estimates were also highly correlated with WHR of the faces—the greater the WHR, the higher the aggressive rating, suggesting that we may use this aspect of facial structure to judge potential aggression in others. These findings indicate that subtle differences in face shape may affect personality judgments, which may, in turn, guide how we respond to certain individuals.

Some day these results will lead to an important offspring genetic engineering question: Genetically engineer your kid to look more aggressive than he is in order to intimidate would-be challengers? Or genetically engineer him (or her) to look meek while being ready, willing, and able to aggressively pursue goals?

You don't want to engineer your kid to be physically aggressive but weak or poorly coordinated. Though it'll probably be possible to genetically engineer more for an aggressiveness useful for success in business and less for aggressiveness that leads to time in prison for assault and murder.

Update: Most personality traits are readable from facial expressions. We really are open books.

AUSTIN, Texas—First impressions do matter when it comes to communicating personality through appearance, according to new research by psychologists Laura Naumann of Sonoma State University and Sam Gosling of The University of Texas at Austin.

Despite the crucial role of physical appearance in creating first impressions, until now little research has examined the accuracy of personality impressions based on appearance alone. These findings will be published in the December 2009 issue of Personality and Social Psychology Bulletin, co-written with Simine Vazire (Washington University in St. Louis) and Peter J. Rentfrow (University of Cambridge).

"In an age dominated by social media where personal photographs are ubiquitous, it becomes important to understand the ways personality is communicated via our appearance," says Naumann. "The appearance one portrays in his or her photographs has important implications for their professional and social life."

In the study, observers viewed full-body photographs of 123 people they had never met before. The targets were viewed either in a controlled pose with a neutral facial expression or in a naturally expressed pose. The accuracy of the judgments was gauged by comparing them to the aggregate of self-ratings and that of three informants who knew the targets well, a criterion now widely regarded as the gold standard in personality research.

Even when viewing the targets in the controlled pose, the observers could accurately judge some major personality traits, including extraversion and self-esteem. But most traits were hard to detect under these conditions. When observers saw naturally expressive behavior (such as a smiling expression or energetic stance), their judgments were accurate for nine of the 10 personality traits. The 10 traits were extraversion, agreeableness, conscientiousness, emotional stability, openness, likability, self-esteem, loneliness, religiosity and political orientation.

Does the personality shape the face? Or do genetic factors shape them both?

By Randall Parker 2009 November 01 04:23 PM  Brain Innate
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Sleep Deprivation Cut Mental Function

The brain downshifts to simpler ways of processing information when lacking sleep.

Westchester, Ill. —A study in the Nov.1 issue of the journal Sleep shows that sleep deprivation causes some people to shift from a more automatic, implicit process of information categorization (information-integration) to a more controlled, explicit process (rule-based). This use of rule-based strategies in a task in which information-integration strategies are optimal can lead to potentially devastating errors when quick and accurate categorization is fundamental to survival.

The experimental subjects were West Point cadets. So they were at similar ages, pretty healthy, and smarter than the average population. The decay here is an average. I would be curious to know what the outliers looked like. Likely a subset suffered more severe cognitive decay when sleep-deprived.

Results show that sleep deprivation led to an overall performance deficit on an information-integration category learning task that was held over the course of two days. Performance improved in the control group by 4.3 percent from the end of day one to the beginning of day two (accuracy increased from 74 percent to 78.3 percent); performance in the sleep-deprived group declined by 2.4 percent (accuracy decreased from 73.1 percent to 70.7 percent) from the end of day one to the beginning of day two.

According to co-principal investigators W. Todd Maddox, PhD, professor of psychology, and David M. Schnyer, PhD, associate professor of psychology at the Institute for Neuroscience at the University of Texas in Austin, fast and accurate categorization is critical in situations that could become a matter of life or death. However, categorization may become compromised in people who often experience sleep deprivation in fast-paced, high pressure roles such as doctors, firefighters, soldiers and even parents. Many tasks performed on a daily basis require information-integration processing rather than rule-based categorization. Examples include driving, making a medical diagnosis and performing air-traffic control.

It would be useful to know for each person how rapidly their brain function deteriorates with lack of sleep. Even more useful: an easily administered sleep impairment test that would let one know whether one is currently sleep impaired and if so by how much. Think of it as akin to an alcohol breath test to determine whether you are safe to drive. Some who is both sleep impaired and alcohol impaired especially ought not drive.

Here's the part I find especially interesting: Not all of the sleep-deprived subjects shifted to rules-based strategies for processing information. Would a more severe degree of sleep deprivation eventually cause everyone to shift to less effective approaches for cognitive processing?

Maddox and Schnyer were surprised to find that the source of the information-integration deficit was a subgroup of sleep-deprived individuals who shifted from information-integration strategies when rested to rule-based strategies when sleep deprived. Sleep-deprived participants who used information-integration strategies in both sessions showed no drop in performance in the second session, mirroring the behavior of control participants.

A brain scan that measures white matter distribution might provide predictive results over how each person's brain will respond to sleep deprivation.

The study cites previous research suggesting that differences in cortical white matter predict cognitive vulnerability to the effects of sleep deprivation.

What I want: a watch that would let me know with a sliding bar or color coding just how sleep-deprived I am at the moment. While I'm wishing: the watch also ought to tell me about nutrient deficiencies detected by nanosensors embedded in my body. When will we get such a capability? 2020? 2025?

By Randall Parker 2009 November 01 03:25 PM  Brain Sleep
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