2006 May 31 Wednesday
Ritalin Boosts Norepinephrine Against ADHD

Insights into how Ritalin boosts ability to focus attention:

BETHESDA, MD. (May 30, 2006) – Methylphenidate (Ritalin) elevates norepinephrine levels in the brains of rats to help focus attention while suppressing nerve signal transmissions in the sensory pathways to make it easier to block out extraneous stimuli, a Philadelphia research team has found.

Their report in the Journal of Neurophysiology helps explain how a stimulant aids people with attention deficit and hyperactivity disorders to improve their focus without increasing their motor activity. Methylphenidate, prescribed under the brand name Ritalin, has been used for more than 20 years, mostly in children, to treat attention deficit hyperactivity disorder (ADHD) and attention deficit disorder (ADD). The drug can also help people who don't suffer either disorder to attend better to a cognitive task.

Despite its wide use, little is known about how the drug, a chemical cousin of amphetamines, produces its therapeutic effects. Researchers want to unlock the mystery of why the drug has the paradoxical effect of decreasing hyperactive behavior and increasing the ability to focus, even though it is a stimulant, said Barry Waterhouse, the study's senior author.

"We're developing a series of behavioral and electrophysiological assays for examining the actions of drugs like methylphenidate," Waterhouse said. "If we can show exactly how methylphenidate works, we may be able to produce even more effective drugs and provide a better understanding of the physiology underlying ADHD."

The study, using rats, is the first to document the increase in norepinephrine and suppression of the neuronal response in this sensory pathway of the brain. "Methylphenidate enhances noradrenergic transmission and suppresses mid- and long-latency sensory responses in the primary somatosensory cortex of awake rats," by Philadelphia-based researchers Candice Drouin, University of Pennsylvania; Michelle Page, Thomas Jefferson University; and Barry Waterhouse, Drexel University College of Medicine appears online in the Journal of Neurophysiology, published by The American Physiological Society.

Can Ritalin boost the mental performance of the average person? It is increasingly popular with college students. Should brain workers be taking it in order to boost their productivity?

The development of better drugs to increase the ability to focus will eventually result in strong market pressures for their use. Workers who do not take such drugs will find it increasingly difficult compete with those who embrace cognition-enhancing drugs.

Modafinil can not compete with amphetamines for treating ADHD.

"The larger effect sizes we calculated for stimulant ADHD medications, compared to nonstimulants or the novel stimulant modafinil, leads us to conclude that amphetamine and methylphenidate based stimulant medications are more effective in treating symptoms of ADHD," said Stephen V. Faraone, Ph.D., lead researcher and director of child and adolescent psychiatry at SUNY Upstate Medical University. "Our results should help physicians who have had to rely on qualitative comparisons among published trials, along with their own clinical experience, to draw conclusions about an ADHD medication's relative efficacy because of largely absent direct head-to-head drug comparisons."

The researchers compared study outcomes using effect sizes, a commonly used, standard statistical measure to determine the magnitude of a particular effect resulting from an intervention, such as a drug used on a population, irrespective of the population size. Effect sizes are generally categorized as small (0.2), medium (0.5) and large (0.8). Standardized mean averages, or effect sizes, for dependent measures in each study were computed by taking the mean of the active drug group minus the mean of the placebo group and dividing the result by the pooled standard deviation of the groups.

After adjusting for the influence of individual study design features, the researchers calculated effect size based on Total ADHD scores. Long-acting and short-acting stimulant medications showed the largest effect size among all medications (E = 0.83 and E = 0.9 respectively), followed by nonstimulant or modafinil based stimulants medications (E = 0.62). Statistically significant differences in effect size occurred in comparisons between nonstimulant/modafinil based stimulant medications and long-acting (p = 0.004) as well as short-acting stimulants (p = 0.002).

For the analysis, Faraone and his colleagues used data from 29 double-blind, placebo-controlled treatment studies of 4,465 children with ADHD, with an average age 10 years, published during or after 1980. Designs for all of the studies were randomized, double-blind with placebo controls that lasted for two or more weeks in populations diagnosed with ADHD as defined using criteria from the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition or Fourth Edition (DSM).

My guess: ADHD is a product of natural selection. Tendency to totally focus on a single subject was probably maladaptive for much of human history.

By Randall Parker 2006 May 31 09:41 PM  Brain Enhancement
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Killing Wild Birds Would Accelerate Bird Flu Spread

Killing wild birds to reduce the risk of H5N1 bird flu exposure in humans would probably backfire and cause the opposite effect.

In fact, Marc Choisy and Pejman Rohani at the University of Georgia at Athens in the US have shown that killing wild animals with a disease like flu could actually lead to more infected animals, not fewer.

This is due to a classic principle of ecology, called compensation. Many wild species produce more offspring than can survive. Hunting removes animals which would otherwise have competed with these excess young, especially as hunters often target bigger, older beasts. So in a hunted population, more young usually survive which compensates – or sometimes even over-compensates – for the loss due to hunting.

But when a disease causes lifelong immunity in its host, most of the older animals in a population have survived it and are therefore immune, leaving only the young susceptible.

A raised death rate of older birds due to hunting would increase food available to younger birds. Therefore more younger birds would survive early youth. These younger birds would be immunologically more immature and at greater risk of getting infected by H5N1 influenza.

The net effect if hunting would depend on the percentage of birds killed and whether the killing of birds was sustained. In the extreme the extinction of a bird species would eliminate it as a bird flu carrier.

In any case, if bird flu becomes pandemic in humans you'll at orders of magnitude greater risk from getting it from humans than from birds.

By Randall Parker 2006 May 31 09:34 PM  Pandemic Signs
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2006 May 30 Tuesday
Bipolar Youth Misread Faces Of Others

Lots of kids who think everyone is hostile toward them have defects in their ability to read the faces of others.

Youth with bipolar disorder misread facial expressions as hostile and show heightened neural reactions when they focus on emotional aspects of neutral faces, researchers at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) have discovered. The study provides some of the first clues to the underlying workings of the episodes of mania and depression that disrupt friendships, school, and family life in up to one percent of children.

Brain scans showed that the left amygdala, a fear hub, and related structures, activated more in youth with the disorder than in healthy youth when asked to rate the hostility of an emotionally neutral face, as opposed to a non-emotional feature, such as nose width. The more patients misinterpreted the faces as hostile, the more their amygdala flared. Such a face-processing deficit could help account for the poor social skills, aggression, and irritability that characterizes the disorder in children, suggest Drs. Ellen Leibenluft, Brendan Rich, Daniel Pine, NIMH Mood and Anxiety Disorders Program, and colleagues, who report on their findings May 29, 2006 in the Proceedings of the National Academy of Sciences.

“Since children seem to have a more severe form of the disorder, they may provide a clearer window into the underlying illness process than adult onset cases,” explained Leibenluft. “Our results suggest that children with bipolar disorder see emotion where other people don’t. Our results also suggest that bipolar disorder likely stems from impaired development of specific brain circuits, as is thought to occur in schizophrenia and other mental illnesses.”

Magnetic Resonance Imaging (MRI) studies have shown that, unlike in adults with the illness, the amygdala is consistently smaller in bipolar children than in healthy age-mates. Also, the NIMH researchers had found earlier that bipolar children falter at identifying facial emotion and have difficulty regulating their attention when frustrated.

Using functional MRI, the researchers measured brain activity in 22 bipolar youth and 21 healthy subjects while they rated faces. In addition to the amygdala, other parts of the emotion-regulating circuit — nucleus accumbens, putamen, and left prefrontal cortex — were also hyperactive in patients, compared to healthy peers, during the emotional tasks. Patients rated themselves as more afraid, and they rated the faces as more hostile, compared to healthy peers. The groups did not differ on nose width ratings, confirming that the differences were specific to perceiving emotional processes.

This has practical implications for governments: Political candidates for high office and diplomats could get tested under fMRI machines for their ability to correctly read the faces of others. It just would not do to have some President or Prime Minister imagining lots of hostile intent that is not there. Same holds true for police.

It would be helpful for each person to know what types of facial expression misreadings they are prone to.

This reminds me of a previous report that found when kids enter puberty they go through a period of decreased ability to read the emotions of others.

By Randall Parker 2006 May 30 10:33 PM  Brain Disorders
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2006 May 29 Monday
Affordable Energy Can Solve Water Shortages

Some folks like to fantasize and prophesize about how this or that trend is going to eventually bring about a collapse of civilization. FuturePundit has a few worries about the continued existence of humanity. But most of the scenarios about civilizational collapse are extremely unlikely. One scenario promoted in some circles is a worldwide shortage of fresh water. The exhaustion of fresh water resources poses a problem for the poorer countries in the world. But industrialized economies which can afford to produce large amounts of energy can not collapse due to shortages of fresh water. A Technology Review survey of the water desalinization industry in Spain provides some useful data about water desal costs.

One of the main challenges that remains with the desalination process is the cost of the energy required to produce freshwater. Though different processes demand varying amounts of energy (desalting seawater with membranes requires the most, as it takes tremendous pressure to push the water through the membrane), it remains an issue in terms of cost and environmental issues, as nations around the world battle rising greenhouse gas emissions, such as those emitted by power stations.

In the last 30 years, the amount of energy required for desalination has fallen precipitously, and along with it the price. Decades ago it took approximately 12 kilowatt-hours of energy to produce one cubic meter of freshwater using RO technology; today it takes on average between 3 and 4 kilowatt-hours of energy. Even today, however, the cost of that energy makes up about 40 percent of the total cost to produce each cubic meter of water.

“We are very close to the minimum energy for desalination,” says Juan Maria Galtés, director of special projects for Inima. “There’s a point where it’s impossible to go any further,” because of the high pressure needed to separate salt from water.

Developments in new kinds of membranes or other tweaks in plant efficiency could help engineers continue to shave off small amounts of energy, reducing both the cost and the environmental impact.

A cubic meter is 264.173 gallons. Electric costs vary within and between countries. But 10 cents a kilowatt-hour for retail sales is close enough to the average to be useful for rough calculations. The 4 kilowatt-hours needed to produce 1 cubic meter of water therefore cost about 40 cents. Since the article claims energy is only 40% of the cost of desalinization that suggests desal costs about $1 per cubic meter (these are high side estimates btw). Maybe the Spaniards assumed higher or lower cost per kwh of electricity. So that's a rough guess. But a useful one. See below where I connect that number to information about how much water the United States uses.

New nuclear plants probably could produce electricity for less than 5 cents per kwh. But what about solar and wind? They cost more. But in theory their lack of continuous availability shouldn't pose a problem since we could store up purified water when the sun shines and the wind blows. But the problem with this idea is that current designs of desal plants require continuous availability of power. However, industry and governments are looking for ways to make desal from non-continuuos energy sources more feasible.

The engineering involved in using renewable energy to power a desalination plant can be relatively simple: solar or wind generators can be hooked up to an existing utility grid, which then offsets the power demands of the desalination plant.

The challenge, however, in coupling desalination directly with renewable energy such as solar or wind power lies in the variability of renewable energy. The membranes used in reverse osmosis need to be kept wet, and the systems that make up a desalination plant have been developed to handle a steady stream of water. Solar energy is plentiful when the sun shines and wind power only when the wind blows.

Researchers in the Canary Islands have spent the past decade developing stand-alone small plants that could provide water for approximately 100 to 300 families, about the size of a small village in a developing country. ITC projects are also carried out in conjunction with other international research institutes or companies.

On one Canary Island test site, photo-voltaic panels are hooked up to a battery, which feeds a steady supply of electricity to a small desalination plant. “But batteries aren’t great because you have to replace them after, say, five or 10 years, and then you have to dispose of them as well,” says Piernavieja. “It’s better to develop a system that needs no batteries in the first place.”

Some day really cheap photovoltaics combined with cheaper equipment for doing desalinization will make desalinization much cheaper. But for now nuclear power would be tbe best way to scale up desalinization - unless you are willing to either let coal burning electric plants pollute or to pay much more for cleaner coal burning plants.

I like to work out costs of switching from current methods of getting resources to alternative methods because the costs of alternatives represent worst cases for what happens if we really do run out of this or that resource. Suppose the United States had to totally switch over to using only desalinated water. The US uses 40 billion gallons of water per day.

A report by the U. S. Geological Survey (USGS), "Estimated use of water in the United States in 2000" (USGS Circular 1268), shows that about 408 billion gallons of water per day were withdrawn for use in the United States during 2000. Withdrawals in 1990 averaged nearly 1,620 gallons per day per person; in 2000, the per capita average had declined to about 1,430 gallons per day. During the same decade, the United States experienced a population increase of about 33 million. Total withdrawals increased steadily from 1950 to 1980 but have varied less than 3 percent since 1985.

That 408 billion gallons of water per day amounts to about 1.544 billion cubic meters. Well, if desalinization of water costs about $1 per cubic meter then it would cost about $1.54 billion per day or $563.7 billion per year to get all water in the United States from desalinization. That would be rather expensive and the price of water would get so high that people would find many ways to drastically cut their water usage. So it is unlikely we'd ever spend a half trillion dollars a year on water even if the United States suffered a massive continent-wide drought. But since the United States has a $12.4 trillion a year (and growing) economy it could afford to spend a half trillion a year on water.

A massive shift to desalinization plants could be done in concert with a nuclear power plant building program to lower the cost of electricity. Plus, huge demand for desal would drive the development of cheaper desal technology. So the cost of desalinated water would drop for a couple of reasons. At the same time, the higher price for desalinated water would drive demand for a shift to technologies that used water more efficiently and therefore lowered the demand for water. As a consequence of all this I'd be surprised if a shift to desalinated water would cost more than a couple hundred billion dollars per year. To put that in perspective, our current approximately 21 million barrels of oil consumed per day in the United States works out to about 7.6 billion barrels per year. Well, an oil price rise from $20 to $60 per barrel cost about $300 billion per year. Worse yet, most of that money was exported.

A continent-wide drought is probably not possible. But if it happened our need for crop irrigation would rise to compensate for lack of rains. However, we could switch to the methods of agriculture used in Israel and reduce evaporation with ground covering, no-till farming, and plant more crops with lower water needs.

Mind you, I do not expect a massive nationwide drought that dries up all the rivers. IRather, the lesson here is that shortages of other resources can be solved given energy which is cheap enough. Given sufficiently energy we can solve other resource limitation problems by performing filtration, purification, and many other processes on readily available forms of matter to produce anything we might need for food, shelter, transportation, and other needs.

Some might argue we couldn't run massive desal plants because we are headed for an economic collapse due to a world wide peak and decline in oil production. But we can convert coal into liquid fuels for about $40 to $45 per barrel. Plus, we can run the desal plants on nuclear power. So sorry doomsters. There's no bone dry Mad Max Peak Oil Apocalypse awaiting us in the future.

Update: About half of the water used in the United States is used for electric plant cooling.

Thermoelectric-power plants accounted for 48 percent of total withdrawals (195,000 million gallons per day [Mgal/d]) in 2000. Surface water was the source for more than 99 percent of total thermoelectric-power withdrawals, one third of which were saline. Historically, large supplies of water, mainly for cooling, had to be available to operate thermoelectric-power plants. For this reason, large power plants have been sited near the oceans, the Great Lakes, the Gulf of Mexico, and large rivers.

Withdrawals for irrigation were about 137,000 Mgal/d, second only to thermoelectric power nationwide. Irrigation represented 34 percent of total withdrawals and 40 percent of total freshwater withdrawals. Eighty-six percent of irrigation withdrawals, and 75 percent of the total land irrigated in 2000 were in the 17 conterminous Western States. Withdrawals for irrigation have remained nearly stable since 1985 despite an 8-percent increase in total acres irrigated.

Since salt water is usable for power plant cooling a large number of nuclear power plants sited near coastlines to generate electricity for desalinization would not themselves increase the demand for fresh water. Also, if fresh water ever become extremely scarce then salt water could be piped inland for use in cooling inland electric power plants.

If fresh water was made into a market then rising prices would provide incentives for much more efficient water usage. In the event of severe water shortages the most rational response would be to create water markets.

Update II: Rates of water usage vary greatly within the United States.

For instance, per capita use of public water is about 50 percent higher in the West than the East mostly due to the amount of landscape irrigation in the West (see map below). However, per capita use can also vary greatly within a single state. For example, in 1985 the demand for municipal water in Ancho, New Mexico, totaled 54 gallons per capita per day (gal/cap/day) while in Tyrone, New Mexico, municipal demand topped off at 423 gal/cap/day (Grisham and Fleming, 1989). Rural areas typically consume less water for domestic purposes than larger towns.

The areas that have high usage rates could cut way back to rates closer to what the lower usage areas have. Granted, there'd be a lot less lawn grass. But civilization would not teeter, let alone collapse.

By Randall Parker 2006 May 29 08:46 PM  Energy Policy
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2006 May 28 Sunday
Dopamine Receptor Genetic Variant Influences Sexuality

Genetic variations in a dopamine receptor influence sexuality (same article here)

New evidence that individual differences in human sexual desire can be attributed to genetic variations has been revealed by a research group headed by a professor of psychology at the Hebrew University of Jerusalem. The findings are believed to have an impact on people’s understanding of their own sexuality as well as to how sexual disorders may come to be treated in the future.

An article on the topic appears currently in Molecular Psychiatry online. The study represents the combined efforts of researchers directed by Prof. Richard P. Ebstein, of Herzog Hospital and the head of the Scheinfeld Center for Human Genetics in the Social Sciences of the Psychology Department at the Hebrew University, and a research group headed by Prof. Robert H. Belmaker of the Psychiatry Division of Ben Gurion University of the Negev.

The article provides, for the first time, data that common variations in the sequence of DNA impact on sexual desire, arousal and function and lead to differences and diversity of the human sexual phenotype.

Did anyone previously not expect this to be the case? The press release gushes on about how this is a revolutionary discovery that will affect how we look at sexuality. Maybe that is true for some people who do not want to accept that genetic variations play a large role in determining our desires, dislikes, and behavioral tendencies and abilities. But I expect genetic roles in all sorts of aspects of cognitive function and in the peripheral nervous system. I just am eager and impatient to get to the details so we can work out the implications.

Self-reports on sexuality correlate with DRD4 dopamine receptor genetic variations.

In this latest study, the Israeli investigators examined the DNA of 148 healthy male and female Israeli university students and compared the results with questionnaires asking for the students’ self-descriptions of their sexual desire, arousal and sexual function. The results showed a correlation between variants in the D4 receptor gene – which is responsible for producing the dopamine receptor protein (DRD4) – and the students’ self-reports on sexuality.

Sounds like only 10% had moderate sexual desire and most were in the "depressant" category. I bet divorces are more likely between members of a couple who have radically different levels of sexual desire. Therefore genetic tests may eventually help to predict likelihood of marital success.

Interestingly, some forms of variants in this gene were shown to have a depressing effect on sexual desire, arousal and function, while other common variant had the opposite effect – an increase in the sexual desire score. The latter is believed to be a relatively new mutation, and it is estimated that it appears in Homo sapiens “only” 50,000 years ago at the time of humankind's great exodus from Africa. Approximately 30% of many populations carry the heightened arousal mutations, while around 60% carry the depressant mutation.

Did the migration from Africa take humans into areas where so much food was available that it was selectively advantageous to mate and reproduce more often?

Which are the populations that have a higher average level of sexual arousal? Does the level of sexual arousal correlate with other characteristics?

The discovery of a role for DRD4 in sexual arousal makes it a candidate target for drug development. Further research into the mechanism for how it causes this effect will likely lead to identification of other targets for sexual arousal drugs.

The investigators predict that as a result of their work, and other advances in neurosciences focusing on sexual behavior, a conceptual change will result, in which new therapeutic pathways will be developed for treatment of sexual dysfunctions based on a rational pharmacogenetic strategy. Additionally, the investigators note that many variations such as “low sexual desire” may be quite normal and not necessarily a product of dysfunction.

Viagra, Levitra, and Cialis are not enough. People want more ways to make themselves sex-crazed. Don't worry. The cheaper genetic sequencing gets the more genetic variations we'll discover that contribute to sexual arousal and the more targets for drug development that will be identified.

When it becomes possible to select the genetic variants offspring will get will more people select higher, lower, or medium sex drive genetic variations? I'm guessing women will want to give their daughters genetic variations that make multiple orgasms very easy. Will people want their kids to walk around constantly craving sexual experiences?

By Randall Parker 2006 May 28 04:00 PM  Brain Sexuality
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Brains Recognize Male Versus Female Gait

The brain can identify male versus female gaits when the only visible features of walkers are only 15 dots of light attached to major body joints.

LA JOLLA, CA - It doesn't take John Wayne's deliberate, pigeon-toed swagger or Marilyn Monroe's famously wiggly sway to judge a person's gender based on the way they move. People are astonishingly accurate when asked to judge the gender of walking human figures, even when they are represented by 15 small dots of light attached to major joints of the body.

And not only that, when human observers watched the walking motion of a male so-called "point light walker," they were more sensitive to the female attributes when watching the next figure in the sequence. This suggests that the human brain relies on specialized neurons that tell gender based on gait, report researchers at the Salk Institute for Biological Studies in the May 21 advance online edition of Nature Neuroscience.

"Our judgment of gender can adapt within seconds," says senior author Gene Stoner, a neuroscientist in the Vision Center Laboratory at the Salk Institute. "The gaits of males and females may vary geographically or culturally and this mechanism allows us to adapt very quickly to local ways of walking," he adds.

How humans move reflects, in part, gender-specific differences in shape such hip-to-waist ratio and the like. Such inherent differences in gait might then be exaggerated by an individual to emphasize their gender. "Our new data suggests that there are neurons selective for gender based on these motion cues and that they adjust their selectivity on the fly," Stoner explains.

Although much work has been done on how the brain represents so-called low-level features, such as "redness" or "left-moving," scientists have been unable to put their finger on more abstract concepts such as gender. "We wanted to know whether gender is represented in a similar way to low-level visual features such as color, or if it is a more semantic concept such as good and evil," says experimental psychologist and first author Heather Jordan, a former post-doc in the Vision Center Laboratory and now an assistant professor at York University in Toronto.

Individual neurons in the visual cortex are finely tuned to certain attributes of visible objects such as the color red, a certain shape or objects moving in a specific direction. These specialized neurons reveal their existence through a telltale effect called adaptation. For example, if you stare at a red patch and then look at a neutral color you tend to see green. This "adaptation" reflects a mechanism in the brain that exaggerates differences between objects to increase the sensitivity and optimize the output of individual neurons.

I think the ability to recognize differences is something that one could enhance with thoughtful control of one's environment. What differences do you want to get better at recognizing?

These scientists expect to eventually identify a single neuron that activates for male gaits and another neuron that activates for female gaits.

"In the past, when adaptation in behavior was observed for specific features, neurophysiologists have subsequently been able to find individual neurons which fire only when they encounter this feature," says Jordan. "We think that the same is true for maleness and femaleness - that there are neurons in the brain that fire if, and only if, they 'see' a male gait and others that fire if, and only if, they 'see' a female gait, explains Jordan.

"We know lots about individual neurons that are sensitive to the direction of moving objects. But in this case, motion provides information about the structure of what is moving," says Stoner.

The mind compares gaits to recently seen gaits of other walkers. So you are more likely to be seen as masculine after the mind has just seen an especially feminine walk and you are more likely to be seen as feminine after the mind has just seen an especially masculine walk.

For their experiments, the Salk researchers morphed the gait of averaged male and female walkers -- resulting in varying degrees of "maleness" and "femaleness" .When the figure consisted of less than 49 percent male contribution, the observers reported seeing a figure that appeared female. Once there was more than 49 percent maleness in the figure, they reported seeing a figure that was mostly male. But these numbers were not stable: Viewing the gait of one gender biased judgments of subsequent gaits toward the opposite gender. "If you want to appear particularly feminine you should walk behind a very masculine-looking male and vice-versa," jokes Jordan.

If it all comes down to individual neurons then I'd expect an age-related degeneration in the ability to recognize male versus female gaits. Should just the right neuron die then one might lose the ability to tell apart males and females. Though the odds of losing that neurons are low the odds rise with age. Though perhaps there's a mechanism where another neuron can take over the job if the one neuron doing the job dies or starts to misfire.

Given that there are individual neurons that consolidate information for a large assortment of pattern recognition tasks one might have a better chance of identifying loss of function due to deaths of individual neurons if one measured a large number of capabilities (e.g. ability to tell colors apart, direction of movement, various types of shapes, and ability to identify male and female gaits) through time. Error rates might rise before total failure sets in.

Question: If you've just heard a speech from an obviously dishonest person then are you likely to think the next person is honest if they sound relatively less dishonest? If so, this might explain why politicians and political activists can get away with telling so many lies. They get compared to each other rather than to an absolute standard of honesty.

More generally, are there specific types of images or other stimuli one could present to one's brain before examining some evidence or issue as a way to increase one's ability to see a contrast and recognize key differences?

By Randall Parker 2006 May 28 08:07 AM  Brain Sexuality
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2006 May 25 Thursday
H5N1 Bird Flu Human To Human Transmission?

The World Health Organization is pondering whether to raise the level of alert on H5N1 avian influenza.

JAKARTA, Indonesia, May 24 -- The World Health Organization might soon convene an expert panel to decide whether an unprecedented human outbreak of bird flu in Indonesia should trigger a higher global alert for a possible pandemic, health officials said Wednesday.

Why this concern? Suspected Human-To-Human (H2H) transmission of bird flu in 8 members of an Indonesia family got bird flu. Only 1 survived! A strain this lethal would exact a terrible toll if it mutates into a pandemic strain.

Indonesian health authorities this week confirmed that the virus had killed at least six members from one extended family on Sumatra island, including a 32-year-old man Monday. A seventh family member also died from what investigators suspect was bird flu, but she was buried before samples could be taken. Another relative is hospitalized with a confirmed case and is recovering.

Experts fear the bird flu spread in this family from person to person person.

May 24, 2006 (CIDRAP News) – For the first time, evidence suggests that the H5N1 avian influenza virus may have passed from one person to another and on to a third, according to a World Health Organization (WHO) official.

Referring to the extended-family case cluster in Indonesia, the WHO's Maria Cheng told the Canadian Press (CP) yesterday, "This is the first time we have seen cases that have gone beyond one generation of human-to-human spread."

The big fear about bird influenza is that it could mutate so that such human-to-human transmission becomes easy.

Even the first case in this cluster had no easily identifiable animal source of initial exposure.

One of the major puzzles about the cluster, in which human-to-human-to-human transmission is suspected, is the lack of an identifiable animal source of infection for the first case. Steven Bjorge, a WHO epidemiologist in Jakarta, told the AP that the 37-year-old deceased woman who is regarded as the first case-patient might have picked up the virus in her home or workplace. She died April 29 and was buried before samples could be collected for testing, but the WHO believes her illness was avian flu.

"We believe she may have had some contact either with dead or dying chickens in her household or through her activities as a vegetable grower and a seller in a market," Bjorge said of the woman.

The family were exposed to each other and members successively became sick.

On April 29, three people who later fell ill shared a small room with the mother of the family, who was gravely ill and coughing, and has since died. Others who have been stricken cared for family members who were dying. There are no cases reported in the village outside of the family.

The fact that other members of their village have not yet become ill is good news. Hopefully this cluster won't get any larger.

Recombinomics influenza commentator Henry Niman argues that the incubation time of H5N1 bird flu is overestimates by some public health officials and therefore they are underestimating the extent of human-to-human transmission.

WHO assumes that the incubation time for bird flu in humans is 7 to 10 days, longer than that of regular flu, she said.

Henry Niman, who runs recombinomics.com, a Web site tracking the genetics of flu cases, argues that the incubation period is closer to the two to four days of regular flu, so the boy may have been infected by another family member, meaning that the virus may have made three consecutive human-to- human jumps.

But Cheng said the health agency's "working hypothesis" was still that it had jumped only twice.

Niman thinks the number of human-to-human (H2H) clusters has been underestimated due to the overestimate of the H5N1 incubation time. Niman therefore believes that we are already at phase 4 of the development of a pandemic virus strain. Phase 5 would include a much higher level of H2H transmission. Phase 6 would be "it is time to move to that cabin in the country with lots of survivalist supplies".

I do not know if or when H5N1 will mutate into a pandemic strain. I hope it does not. But if it does then you should prepare yourself to rapidly and radically restructure your life to decrease your odds of getting exposed to carriers.

By Randall Parker 2006 May 25 08:58 PM  Pandemic Signs
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Protein Target Found To Block Muscle Atrophy

A drug and a gene therapy can block muscle atrophy in mice which get little exercise.

Researchers in Purdue University's School of Veterinary Medicine have discovered genetic and drug-treatment methods to arrest the type of muscle atrophy often caused by muscle disuse, as well as aging and diseases such as cancer.

The findings might eventually benefit people who have been injured or suffer from diseases that cause them to be bedridden and lose muscle mass, or sometimes limbs, due to atrophy, said Amber Pond, a research scientist in the school's Department of Basic Medical Sciences.

...

"We've found a chemical 'switch' in the body that allows us to turn atrophy on, and, from that, we also have learned how to turn atrophy off."

A protein called Merg1a plays a key role in allowing or blocking muscle atrophy and atrophy can be blocked by an antihistamine which targets Merg1a and also by gene therpy.

The research team found atrophy of skeletal muscle in mice could be inhibited with both gene therapy and drug treatment using astemizole (as-TEM-uh-zole), an antihistamine. This new insight has potential in many different areas of research, Pond said.

"We have discovered a direct link between atrophy and a protein in the skeletal muscle," Pond said. "This led us to develop methods that would block the protein's ability to cause atrophy. Through drug treatment, we were able to block atrophy, allowing muscle to retain 97 percent of its original fiber size in the face of atrophy."

Astemizole, which was withdrawn from the market in 2000 because of its potential to cause serious cardiovascular problems, wouldn't be suitable for use in humans, Pond said. The drug can be used in mice because it doesn't affect their hearts to the same extent.

While the drug used in the experiment isn't suitable for human use this discovery points toward a direction for drug development to prevent muscle atrophy with cancer, age, or low exercise.

A mutant form of Merg1a inserted with gene therapy prevented muscle atrophy in low exercise mice.

This method allowed the scientists to demonstrate the effects of skeletal muscle atrophy and investigate reasons for the link with the Merg1a protein. The Merg1a protein is a channel that normally passes a small electrical current across the cell.

The researchers implanted a gene into the skeletal muscle that resulted in a mutant form of this protein that combines with the normal protein and stops the current. The researchers found that the mutant protein would inhibit atrophy in mice whose ability to use their back legs was limited.

Because gene therapy is not yet a practical treatment option in humans, the researchers decided to go a step further and stop the function of the protein with astemizole, which is a known "Merg1a channel blocker." The researchers found that the drug produced basically the same results as the gene therapy. In fact, muscle size increased in mice in the group that were given the drug without any other treatment.

"We are now looking at the differences in the structure of the heart and the skeleton to give us clues on how to specifically target muscles without the cardiac side effects," Pond said.

A lot of people would love to have the effects of exercise last longer. Also, a method to avoid muscle atrophy with age would have very wide appeal.

By Randall Parker 2006 May 25 12:19 AM  Biotech Manipulations
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Laser Microbubbles May End Need For Reading Glasses

Here's a technological advance which will be popular when it reaches the market.

Presbyopia---the inability to focus on close objects resulting in blurred vision---affects 100 percent of people by age 50. Historically, laser correction of the intraocular lens for presbyopia has been proposed, but it is risky because there is no way to monitor the procedure---no way for ophthalmologists to see what they are doing to the lens being cut.

But a tool developed at the University of Michigan allows for a potentially noninvasive, painless fix to presbyopia using tiny bubbles that help ophthalmologists reshape the eye’s lens and restore its flexibility and focusing ability. Matthew O’Donnell, professor and chair of the U-M Department of Biomedical Research, along with Kyle Hollman, assistant research scientist and adjunct lecturer, and graduate student Todd Erpelding, developed the method. Recently, it was successful when tested in pig lenses.

Presbyopia usually starts around age 40, O’Donnell saays. The predominant belief is that fibers created in the intraocular lens accumulate and stiffen, thus making the lens less flexible. Without that flexibility, the lens can’t change shape to focus on near objects, a process called accommodation.

So, while a young eye is like an automatic focus camera, the presbyopic eye can be thought of as a fixed focus camera, he says. One way to potentially solve presbyopia is to laser away some fibers to restore flexibility, but there is no way to know how much or where to cut, he adds.

“There are no noninvasive or minimally invasive procedures for presbyopia,” said O’Donnell, 55, who explained that he started research on presbyopia when he began to notice his own near-sight failing. He held up his reading glasses: “I got sick of wearing these things.”

The U-M tool uses bubbles, ultrafast optics and ultrasound to measure the thickness and rigidity of the lens during laser surgery, thus guiding the surgeon as they reshape the lens. It’s a new application for microscale bubbles, which scientists have experimented with for years in the areas of drug delivery, tumor destruction and other medical applications.

For the treatment of presbyopia, the U-M team used ultrafast laser pulses to create tiny gas bubbles within the intraocular lens. Before the bubbles diffuse, researchers hit them with high frequency sound waves, which push the bubbles against neighboring lens fibers.

“Part of the sound is reflected, and from the characteristic of the reflection, you know where the bubble is,” O’Donnell said. “It uses exactly the same technology as ultrasound imaging.”

In this way, researchers measure how far the bubbles have moved based on the force applied, and thus measure the pliability of the lens.

“The bubbles show you where the laser should cut,” O’Donnell said. “If it’s still too hard, you cut some more. If it’s soft enough, you stop.”

The future plan is to automate the procedure to quickly cover the entire lens with bubbles, he said. The team, which will begin testing this year, is talking with several companies about commercial opportunities.

Growth or synthesis of replacement lenses may also eventually solve this problem.

How will the world look differently 20 years from now? In industrialized countries corrective glasses will be rare, obesity will be rare, and baldness and even hair graying will be rare. What else do you think will be obviously different in a stroll down a city street in the year 2026?

By Randall Parker 2006 May 25 12:17 AM  Biotech Therapies
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2006 May 23 Tuesday
Biotechnology Will Some Day Enable Polygamy

An excellent article by David Kelly and Gary Cohn of the Los Angeles Times provides an overview of Mormon splinter sects which practice polygamy.

COLORADO CITY, Ariz. — For half a century, while polygamous members of this remote enclave engaged in widespread sexual abuse and child exploitation, government authorities on all levels did little to intervene or protect generations of victims.

Here in the sparsely populated canyon lands straddling Arizona and Utah, members of the Fundamentalist Church of Jesus Christ of Latter-day Saints, or FLDS — an offshoot of Mormonism — live by their own rules.

The expulsion of boys of at the early ages of 13 and 14 for rules infractions is one of the more amazing things the polygamists do. In order to have enough women to go around they have to have fewer men.

Boys are thrown out of town, abandoned like unwanted pets by the side of the road and forcibly ostracized from their families to reduce competition among the men for multiple wives.

Children routinely leave school at age 11 or 12 to work at hazardous construction jobs. Boys can be seen piloting dump trucks, backhoes, forklifts and other heavy equipment.

Girls work at home, trying to keep order in enormous families with multiple mothers and dozens of children who often eat in shifts around picnic tables.

Wives are threatened with mental institutions if they fail to "keep sweet," or obedient, for their husbands.

I think polygamy may become more prevalent in the future and I think advances in biotechnology will make this possible. First of consider that the polygamists face two problems (legal problems aside) as far as human nature is concerned: A) They need several women per man and yet their babies are born like others with nearly equal ratio between males and females; and B) Women want husbands of their own, not shared. Biotechnically speaking, these are both solvable problems.

First off, a company called Microsort can already solve the sex ratio problem (though I suspect they would avoid knowingly doing business with polygamists). They have a method of sorting sperm that selects out male and female sperm (i.e. sperm with Y versus X chromosomes). This method isn't 100% efficient. But the technology could be used to produce offspring that are overwhelmingly female. Also, selective abortion guided by ultrasound sex detection is widely used in India and China to abort a substantial fraction of all female fetuses. The same technology could instead guide selective abortion of male fetuses of women in polygynous marriages.

In the longer run easier and cheaper methods to select offspring sex will become available. Methods that do not require cooperation of a company or even of a doctor and which are much cheaper will eventually lower the barriers for doing offspring sex selection. When such technologies become available I would be surprised if polygamous religious sects do not use them.

Then there's the problem of human nature. Consider that these polygamists are already managing to condition many women into lives of polygynous wives (polygyny is one husband and many wives) and that they succeed in this in spite of human nature as it exists today. Imagine the world 10 years hence when we will know many genetic variations that influence the tendencies toward jealousy, possessiveness, promiscuity, and other personality characteristics that affect mating behavior. Just by selecting among existing genetic variations it will be possible to have female offspring that will find polygyny more tolerable than the average woman does today.

Knowledge of genetic variations which generate the existing range of cognitive characteristics will inevitably lead to the development new genetic variations that widen the range of human desires, urges, instinctive responses, and other behavioral tendencies. I expect scientists will accidentally if not intentionally discover how to produce females who will find polygyny much easier to accept and even to enjoy.

When I look at the hold that charismatic leaders have over their followers, the extreme demands those leaders can successfully make on their followers (e.g. expel your 13 year old son from the community by leaving him somewhere along side a road), and also the assortment of sects (whether religious or secular) that exist today one conclusion I draw from this is that people in various sects (not just polygamist offshoots of the Mormons) will use biotechnologies to achieve their group goals. Some sects will genetically engineer offspring to have characteristics that make them more ideal members of their sect.

Sect leaders will tell their followers that God has entrusted them with the responsibility to make the perfect followers of their doctrines and to create offspring that will better serve God's will. I fully expect we will see members of both small religious sects and major religions genetically engineering their offspring to make better believers and better livers of their doctrines. I do not expect legal barriers to prevent this. There are nearly 200 countries in the world. Some are highly corrupt. Some will allow this to take place in their borders either legally or in exchange for bribes.

Of all the religious sects that will do genetic engineering to make better followers I do not see polygamists who genetically engineer girls to have low jealousy as posing anywhere near the biggest problem for the rest of societies. Sects that make people more intolerant of non-believers and more devout in whatever they believe strike me as far more problematic.

By Randall Parker 2006 May 23 11:20 PM  Bioethics Reproduction
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2006 May 21 Sunday
Dairy Diet Increases Incidence Of Twin Births

Dairy products greatly up the odds of having twins and the use of growth hormone to increase milk production may have increased the frequency of twins.

NEW HYDE PARK, NY – An obstetrician well known for his care of and research into multiple-birth pregnancies has found that dietary changes can affect a woman's chances of having twins, and that her overall chance is determined by a combination of diet and heredity. By comparing the twinning rate of vegan women, who consume no animal products, with that of women who do eat animal products, Gary Steinman, MD, PhD, an attending physician at Long Island Jewish (LIJ) Medical Center in New Hyde Park, NY, found that the women who consume animal products, specifically dairy, are five times more likely to have twins. The study is published in the May 2006 issue of the Journal of Reproductive Medicine, available May 20.

The Lancet recently published an invited comment by Dr. Steinman on dietary influences on twinning in the journal's May 6 issue.

The culprit may be insulin-like growth factor (IGF), a protein that is released from the liver of animals -- including humans -- in response to growth hormone, circulates in the blood and makes its way into the animal's milk. IGF increases the sensitivity of the ovaries to follicle stimulating hormone, thereby increasing ovulation. Some studies also suggest that IGF may help embryos survive in the early stages of development. The concentration of IGF in the blood is about 13 percent lower in vegan women than in women who consume dairy.

The twinning rate in the United States has increased significantly since 1975, about the time assisted reproductive technologies (ART) were introduced. The intentional delay of childbearing has also contributed to the increase of multiple-birth pregnancies, since older women are more likely to have twins even without ART.

"The continuing increase in the twinning rate into the 1990's, however, may also be a consequence of the introduction of growth-hormone treatment of cows to enhance their milk and beef production," said Dr. Steinman.

So there are multiple factors increasing the incidence of twins: older age at time of reproduction, use of in vitro fertilization (IVF), consumption of dairy products, and possibly the use of growth hormone treatment of cows.

The increased incidence of twins has one big drawback. If you want to have smart children then avoid twins.

OBJECTIVES: To determine whether twins have lower IQ scores in childhood than singletons in the same family and, if so, whether differences in fetal growth explain this deficit. DESIGN: Cohort study. SETTING: Scotland. PARTICIPANTS: 9832 singletons and 236 twins born in Aberdeen between 1950 and 1956. RESULTS: At age 7, the mean IQ score of twins was 5.3 points lower (95% confidence interval 1.5 to 9.1) and at age 9, 6.0 points lower (1.7 to 10.2) than that of singletons in the same family. Adjustment for sex, mother's age, and number of older siblings had little effect on these differences. Further adjustment for birth weight and gestational age attenuated the IQ difference between twins and singletons: the difference in mean IQ was 2.6 points (-1.5 to 6.7) at age 7 and 4.1 points (-0.5 to 8.8) at age 9. CONCLUSIONS: Twins have substantially lower IQ in childhood than singletons in the same family. This effect cannot be explained by confounding due to socioeconomic, maternal, or other family characteristics, or by recruitment bias. The reduced prenatal growth and shorter gestations of twins may explain an important part of their lower IQ in childhood.

I wonder if better nutrition for mothers pregnant with twins could at least partially compensate for the effects of carrying twins on brain growth. Maybe a diet higher in omega 3 fatty acids, choline, and/or other nutrients could compensate?

Update: Since twinning rates fall during periods of food shortage (as happened during World War II) another interpretation of these results is that vegan women have fewer twins because they are nutrient deficient.

Other scientists say vegan women may bear fewer twins because they are less well nourished. Dr Paul Haggarty of the Rowett Research Institute in Aberdeen says there may be other nutrients that vegan women lack.

So maybe dairy consumption isn't causing an unnatural outcome? Then again, maybe it is.

By Randall Parker 2006 May 21 03:14 PM  Biotech Reproduction
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Misunderstandings Common In Email

Do not expect your written communications to be understood.

In effect, e-mail cannot adequately convey emotion. A recent study by Profs. Justin Kruger of New York University and Nicholas Epley of the University of Chicago focused on how well sarcasm is detected in electronic messages. Their conclusion: Not only do e-mail senders overestimate their ability to communicate feelings, but e-mail recipients also overestimate their ability to correctly decode those feelings.

One reason for this, the business-school professors say, is that people are egocentric. They assume others experience stimuli the same way they do. Also, e-mail lacks body language, tone of voice, and other cues - making it difficult to interpret emotion.

"A typical e-mail has this feature of seeming like face-to-face communication," Professor Epley says. "It's informal and it's rapid, so you assume you're getting the same paralinguistic cues you get from spoken communication."

I see the same thing all the time in post comment discussions here and all over the blogosphere and in various discussion forum venues and the Usenet. People misinterpret my posts. They misinterpret each other. They get morally indignant and insulting. Things descend from there. I try to read my writings for alternative explanations to reduce the extent of the problem but still expect to be misunderstood some of the time.

Peope think they are just as clear in email as they are on the phone. How can humans be that foolish? (er, never mind, we are that foolish all the time)

Frequency that..EmailPhone
Communicator believes he is clearly communicating78%78%
Receiver believes he is correctly interpreting89%91%
Receiver correctly interprets message56%73%

So then the internet is automating the process of producing misunderstandings! We internet dwellers have more communications misunderstandings than those who still restrict their lives to the real world.

By Randall Parker 2006 May 21 12:27 PM  Comm Tech Society
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Russia Offers Cash For Babies

With a UN report predicting a one third decline in Russia's population by 2050 the Russian government has finally awakened to the scale of the problem they face.

MOSCOW – Cash for babies is the Kremlin's offer to women in its latest bid to reverse a population decline that threatens to leave large swaths of Russia virtually uninhabited within 50 years.

President Vladimir Putin last week defined the crisis as Russia's most acute problem, and promised to spend some of the country's oil profits on efforts to relieve it. He ordered parliament to more than double monthly child support payments to 1,500 rubles (about $55) and added that women who choose to have a second baby will receive 250,000 rubles ($9,200), a staggering sum in a country where average monthly incomes hover close to $330.

The article quotes Russian mothers saying that the sums offered are not large enough to cause them to have another kid. The Russian birth rate has fallen almost in half since communism collapsed. Does the insecurity in Russia make women reluctant to reproduce?

Russia's birthrate, falling for decades, has plunged in post-Soviet times, to just 1.17 in 2004 from 2.08 babies per woman in 1990 - far below the 2.4 children required to maintain the population - according to the Federal State Statistics Service.

I'd like to know what most changed the thinking of Russian women. High unemployment of prospective mates? Higher criminality around them? Their own lower job security? Lower living standards? What?

If I was the Tsar of Russia (which Mr. Putin more or less is at this point) I'd make the money available only to smarter women (say a 115 or 120 IQ threshold) and I'd up the amount offered per woman per baby. Smarter kids will make far larger contributions to Russia's economy and will be less likely to become criminals or unemployed.

Another thought: Offer greater job security to men and women who have large families. Make some kinds of prestigious, highly secure, and well-paying jobs available only to those who have 3 or more kids.

If someone wants to get morally indignant at me for advocating eugenic policies I have an answer for them: Ho hum. Excuse me while I yawn.

Update: Thinking about Russian women who are reticent to have children given current conditions in Russia a thought came to me: When it becomes possible to boost offspring IQ and other desirable traits (about about very good looks?) using genetic engineering that will serve as an incentive to have children. Think about it. Worried how your children might turn out? Worried they will be poor and attracted to a criminal life? Worried whether you will be able to provide them sufficient education to land high paying jobs? If you can be guaranteed your kids will have 130+ IQs then those worries go way down. Again see this chart of how white males in America do as a function of IQ which I linked to above with a comment about criminals and the unemployed. Moms who know their kids will find school and intellectually demanding jobs to be easy are Moms who can look forward to happy times as their children grow up and become adults. Also, genetic engineering applied to embryos will decrease the odds of birth defects and development problems. I figure women will become more eager to reproduce when they can look forward to having successful kids.

By Randall Parker 2006 May 21 12:11 PM  Trends Demographic
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2006 May 19 Friday
MIT Team Sees Thermophotovoltaics As Car Power Source

Here's an unusual approach for generating electricty in a car: Imagine burning fuel to generate an extremely bright light so that the light can strike photodiodes to generate electricity for the various subsystems in cars that need electricity.

MIT researchers are trying to unleash the promise of an old idea by converting light into electricity more efficiently than ever before.

The research is applying new materials, new technologies and new ideas to radically improve an old concept -- thermophotovoltaic (TPV) conversion of light into electricity. Rather than using the engine to turn a generator or alternator in a car, for example, the new TPV system would burn a little fuel to create super-bright light. Efficient photo diodes (which are similar to solar cells) would then harvest the energy and send the electricity off to run the various lighting, electrical and electronic systems in the car.

Such a light-based system would not replace the car's engine. Instead it would supply enough electricity to run subsystems, consuming far less fuel than is needed to keep a heavy, multi-cylinder engine running, even at low speed. Also, the TPV system would have no moving parts; no cams, no bearings, no spinning shafts, so no energy would be spent just to keep an engine turning over, even at idle.

"What's new here is the opportunity for a much more effective energy system to be created using new semiconductor materials and the science of photonics," said Professor John Kassakian, director of the Laboratory for Electromagnetic and Electronic Systems (LEES), where the work was conducted. The idea is to create intense light, let it shine on new types of photo diodes to make electricity, and bounce any excess light back to the light source to help keep it glowing-hot. In theory, Kassakian said, efficiency could be as high as 40 percent or 50 percent.

Of course the "In theory" part means they haven't yet achieved such a high level of efficiency. But I'm surprised that burning fuels could be made to emit such a high percentage of their energy as photons to even make possible such a high efficiency for electric generation. If such a high level of efficiency could be achieved then it would have a lot of other practical uses. How about burning fuel to generate electricity for houses or commercial buildings? Or why not use the electricity to power the car rather than use an internal combustion engine?

By Randall Parker 2006 May 19 04:32 PM  Energy Transportation
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2006 May 17 Wednesday
Amino Acid Leucine Reduces Appetite In Rats

Eating more leucine might help reduce appetite to make it easier to lose weight.

CINCINNATI--A cell-signaling pathway in the brain that is linked to the development of cancer and diabetes is also a key part of networks that regulate food intake, say University of Cincinnati (UC) researchers.

The finding might one day lead to new ways of helping obese people lose weight, either with new drugs or by carefully designing diets that can activate this pathway.

Scientists from UC's Genome Research Institute demonstrated that the signaling pathway mTOR--activated by nutrient and hormonal signals--plays a role in the brain's ability to sense how much energy the body has available.

As more biochemical pathways by which appetite gets regulated become identified and understood in greater detail they become obvious targets for appetite suppressing drug development.

This finding, the researchers say, suggests that very specific micronutrients may drive these pathways in the brain and could lead to a more scientific approach to diet design to help regulate body weight.

The study, led by Randy Seeley, PhD, professor in UC's psychiatry department, appears in the May 12, 2006 issue of the journal Science.

One caveat: These researchers used rats, not humans.

Another caveat: The method of leucine delivery was injection, not diet. They injected it into a specific area of the brain no less. So that's a big caveat. Will it produce the same effect when consumed?

The mTOR pathway is very sensitive to "branched-chain" amino acids, particularly leucine, Dr. Seeley explains. In laboratory studies, he and his team found that when they administered leucine directly to the hypothalamus, a brain region that controls a number of metabolic processes, animals ate less.

Other, similar amino acids did not give the same results.

This animal study, says Dr. Seeley, could eventually have implications for human obesity.

"Rather than basing our diets only on macronutrients like fat or carbohydrates, we might one day be designing diets based on micronutrients like amino acids," he says.

The amount of food consumed dropped by a sixth.

To see whether the mTOR pathway in the hypothalamus responds to amino acids, Seeley injected 1 microgram of leucine directly into the brains of rodents, near the hypothalamus. Over the next day, the rats that received the injection consumed 25 grams of food on average while the control rats consumed 30 g of food.

A reduction in calories consumed by a sixth per day would prevent weight gain in most people. It would also allow for a slow weight loss.

They saw an even larger reduction in calories consumed when leucine was delivered after a 24 hour fast. But to do 24 hour fasts would probably require a far more effective appetite suppressant. If we had such a powerful appetite suppressant we wouldn't need leucine.

You can buy L-Leucine as a powder or capsule. The powder form would be cheaper. I'm not encouraging anyone to try this. Also, if you do try it I would suggest you do so in moderation. Amino acids compete with each other for absorption in a few transport mechanisms that bring amino acids into cells. You don't want to starve your cells of other amino acids by saturating one of those transport mechanisms. Though I'm not sure that's a real problem.

A Yale online survey found people very willing to take risks to lose weight.

New Haven, Conn. - Nearly half of the people responding to an online survey about obesity said they would give up a year of their life rather than be fat, according to a study by the Rudd Center for Food Policy and Obesity at Yale.

The 4,000 respondents in varying numbers between 15% and 30% also said they would rather walk away from their marriage, give up the possibility of having children, be depressed, or become alcoholic rather than be obese. Five percent and four percent, respectively, said they would rather lose a limb or be blind than be overweight.

"We were surprised by the sheer number of people who reported they would be willing to make major sacrifices to avoid being obese. It drives home the message that weight bias is powerful and pervasive," said Marlene Schwartz, associate director of the Rudd Center and lead author of the study in Obesity, which was issued this month.

15% would give up 10 years of life to be skinny.

15 percent said they would trim a decade off their lives for a thinner waistline.

Whatever company comes up with a really powerful yet safe appetite suppressant is going to make billions of dollars in profits. Mind you, such a treatment has to test as safe chiefly for the benefit of regulatory agencies. Many of the potential customers are willing to run bigger risks.

By Randall Parker 2006 May 17 10:01 PM  Brain Appetite
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2006 May 16 Tuesday
Telomeres Wear Down Quicker In Men Than Women

Men live fewer years on average than women do. Telomeres - cap structures on the ends of chromosomes - shorten with age and their shortening may be one cause of aging. A new study finds that telomeres wear down in the cells of aging men more rapidly than in the cells of aging women.

This new study published in the journal “Cytogenetic and Genome Research” shows significantly shorter telomeres and higher erosion rates in men than in women, which likely causes a shorter life expectancy of male cells and tissues.

Human telomeres form the terminal structures of human chromosomes and play a pivotal role in the maintenance of genomic integrity and function. During aging, telomeres gradually shorten, eventually leading to cellular senescence. Therefore, in humans, short telomeres are considered to be a sign of advanced age.

In this study, the authors investigated human telomere length differences on single chromosome arms of 205 individuals in different age groups and sexes by T/C-FISH (telomere/centromere-fluorescence in situ hybridization), which allows precise measurement of individual telomeres.

In all chromosome arms there was a linear correlation between telomere length and donor age. Generally, the men had shorter telomeres and higher attrition rates than the women.

Even if we could lengthen our telomeres doing that might not increase life expectancy. Why? Wearing down of telomeres protects against cancer by reducing the number of times that cells can divided. Lift that limit and our risk of cancer would probably rise.

The development of effective and easy treatments to cure cancer would make telomere lengthening a much more attractive goal.

By Randall Parker 2006 May 16 10:02 PM  Aging Mechanisms
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Venture Capitalist Vinod Khosla Promotes Biofuels

Sun Microsystems co-founder and venture capitalist Vinod Khosla argued in a speech at Stanford that the United States should put taxes in place to assure that oil prices will not fall so as to provide incentives to develop alternatives.

During his speech, titled "Biofuels—Think Outside the Barrel," at the Schwab Center to about 100 energy scholars, economists and policymakers, Khosla outlined three "action items" for switching to biofuels:

  • 70 percent of all new automobiles should be flex-fuel vehicles, giving drivers the option of gasoline or ethanol;
  • 10 percent of gas stations in the United States should distribute ethanol to "achieve criticality";
  • Create a tax on cheap oil to stabilize oil prices in the unlikely event they should fall below $40 a barrel. (Oil is currently $72 a barrel.)

"I don't think oil will ever [fall to] $40 a barrel until an alternative appears," Khosla said. "If an alternative appears, we will see the manipulation of oil prices to drive alternatives out of business. This [tax] is to assure Wall Street that [it] will not be subject to oil price manipulation by Saudi Arabia."

Biofuels might become cost effective once scientists and engineers make cellulosic technologies work. Cheap cellulosic technologies would allow the breakdown of the sugars in complete plants. Switchback grass and other grasses could yield several times more energy per acre than corn. However, I have doubts about biomass even if done much more efficiently than corn. Cheap photovoltaics combined with cheap lightweight batteries would make use of much smaller land areas and also allow use of lands which support little vegetation. Plus, photovoltaics wouldn't use water or cause run-off of fertilizers and pesticides into creeks and rivers.

By Randall Parker 2006 May 16 09:27 PM  Energy Biomass
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2006 May 15 Monday
Johns Hopkins Creates Big NanoBioTech Institute

The folks at Johns Hopkins clearly see which way the technological winds are blowing in biotechnology.

The Johns Hopkins University is preparing to aim enormous research and educational resources at some exceedingly small targets.

Drawing on the expertise of more than 75 faculty members from such diverse disciplines as engineering, biology, medicine and public health, the university today officially launched its ambitious new Institute for NanoBioTechnology.

The institute will strive for major advances in medicine by developing new diagnostic tools and treatments based on interdisciplinary research conducted at the atomic or molecular level. The institute will encourage the movement of these campus breakthroughs into the private sector for further development and marketing. At the same time, institute members will train the next generation of scientists and engineers in this emerging field, offering both graduate-level instruction and a new undergraduate minor in nanobiotechnology.

The functional components of cells are molecules. To measure and manipulate small components requires the development of technology that operate on the same scale as the target systems. Nanotechnology for biological systems therefore is the right approach for the development of great diagnostics, disease treatments, and enhancements.

The Johns Hopkins institute will have 4 main emphases:

  • Diagnostics, including the development of molecular imaging probes that can relay information about the health of a patient's organs and other tissues without the need for a biopsy. Advances in this area promise to greatly enhance the way diseases are diagnosed and treated.
  • Therapeutics, including nanoscale forms of drug delivery, gene therapy, protein therapy and immunotherapy. These will be used to treat diseases such as cancer and asthma and conditions such as spinal cord injuries.
  • Cellular and molecular dynamics, including the use of powerful new tools to study the inner working of cells. This knowledge should help identify causes of disease and new molecular targets that could help cure medical disorders.
  • Health and environment, a research thrust that will use the new tools and techniques of nanobiotechnology in understanding the potential impact of nanotechnology on public health and the environment.

The interdisciplinary nature of the institute makes sense as well. Engineers, chemists, materials scientists, and people from other disciplines are needed in biology to do nanotech for biotech.

Advances in microfluidics will eventually drive the cost of biological science experiments by orders of magnitude. The rate of advance of biological science and biotechnology will greatly accelerate when advances in microfluidics enable the development of minature labs on a chip. Such devices will allow massive numbers of experiments and manipulations of cells and cellular components to be done in parallel at very low cost.

By Randall Parker 2006 May 15 09:10 PM  Nanotech for Biotech
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2006 May 14 Sunday
US Air Force Plans Shift To Coal Derived Jet Fuel

One of the energy questions I'd most like to find answers for: What is the current cost for making liquid hydrocarbon fuels from various starter materials such as natural gas, coal, shale, and biomass materials? I suspect that at $70 per barrel oil now costs more than the production cost of liquid hydrocarbons from non-oil starter materials. But big money is probably holding back investing in massive Fischer-Tropsch coal conversion facilities out of fear that oil production could surge or demand could slacken and drive oil prices down below the costs of making synthetic. Then the synthetic plants would become huge investment losses. That happened with the Beulah North Dakota Great Plains Synfuels Plant which converts coal to a synthetic equivalent of natural gas.

Well, a New York Times article about a United States Air Force plan to shift toward jet fuels made from coal reports that the USAF and industry sources think coal-to-jet fuel would cost the equivalent of $40 to $45 per barrel oil. If they are correct then current oil prices are above long term sustainable prices.

In a series of tests — first on engines mounted on blocks and then with B-52's in flight — the Air Force will try to prove that the American military can fly its aircraft by blending traditional crude-oil-based jet fuel with a synthetic liquid made first from natural gas and, eventually, from coal, which is plentiful and cheaper.

...

The Air Force consumed 3.2 billion gallons of aviation fuel in fiscal year 2005, which was 52.5 percent of all fossil fuel used by the government, Pentagon statistics show. The total Air Force bill for jet fuel last year topped $4.7 billion.

Although the share of national energy consumption by the federal government and the military is just 1.7 percent, every increase of $10 per barrel of oil drives up Air Force fuel costs by $600 million per year.

Mr. Aimone said that if the synthetic blend worked, plans called for increasing its use in Air Force planes to 100 million gallons in the next two years.

Air Force and industry officials say that oil prices above $40 to $45 per barrel make a blend with synthetic fuels a cost-effective alternative to oil-based jet fuel.

This is good news. When we reach a world oil production peak the result will not be Mad Max at Thunderdome. Sorry survivalists. Civilization will not collapse due to declining oil production.

I think survivalists should base their civilizational collapse fears around something more possible like, say, a repeat of the Toba supervolcano or something milder like a Mount Tambora explosion repeat. If you are a leftist or Muslim who wants to fantasize a horrible punishment of the United States then the bulge in the Yellowstone Lake area would probably be your best bet. The US would take a big hit if a repeat of the 6,400 centuries ago eruption happened.

When the volcano in Yellowstone National Park blew 6,400 centuries ago, it obliterated a mountain range, felled herds of prehistoric camels hundreds of miles away and left a smoking hole in the ground the size of the Los Angeles Basin.

Though a repeat of the 650,000 years ago eruption would be a major bummer for the entire world. (same event, slightly different time estimate)

This last happened at the Yellowstone volcano approximately 650,000 years ago. The caldera that it left is 53 miles long and 28 miles wide. In the area surrounding Yellowstone, 3000 square miles were subjected to a flow of pyroclastic material composed of 240 cubic miles of hot ash and pumice. Ash was also thrown into the atmosphere and blanketed much of North America. It can still be identified in core samples from as far away as the Gulf of Mexico.

Getting back to energy: Coal alone looks like it could fill in for oil once oil production peaks. Also, cost effective and environmentally acceptable oil shale extraction looks within the realm of the possible. A sudden oil peak that was not expected by the market would probably cost us a severe recession of a few years long while coal conversion plants and other facilities got built. Then the world economy would bounce back and resume growing.

The longer we go before a world oil peak the easier the transition. We'll have more technologies to bring more alternative energy sources online at lower costs. I'd rather we develop the non-fossil fuels versions of those alternatives more quickly because they'll eventually be cheaper than oil and at the same time much cleaner. Clean air and clean water are good!

By Randall Parker 2006 May 14 01:43 PM  Energy Fossil Fuels
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2006 May 11 Thursday
Kin DNA Analysis Could Catch More Criminals

Genetic samples of relatives can help narrow searches for criminals.

A 1999 Justice Department survey found that 46 percent of jail inmates had at least one sibling, parent or child who had been incarcerated at some point.

All states take DNA from all convicted felons, and many get specimens from a wide range of others.

Using conservative assumptions, Bieber and his colleagues calculated that U.S. law enforcement authorities could increase their "cold hit" rate (the percentage of DNA searches that result in perfect matches) by 40 percent if they were to check the DNA patterns of criminals' family members when searches generate near misses.

Cold-hit rates vary widely today. Assuming they average about 10 percent, Bieber said, a 40 percent increase would bump that rate up to 14 percent.

Some people with expansive views of privacy rights argue that if your relatives all give DNA samples then in effect a search is being done to you without your consent. I can't say that I'm much bothered by that idea. I'm more bothered by the idea that criminals could kill or maim me or rape someone I care about.

Imagine police have suspicions about some guy and he won't provide a DNA sample to test against crime scene evidence. In one case cited in the article police followed a suspect and grabbed a cigarette butt discarded by the suspect. This led to a conviction.

But often time the police have no realistic suspect. A comparison against a massive database of convicted felons might turn up near matches that would lead to investigations of relatives of felons. As DNA databases grow in size descendants of felons could come under suspicion due to near matches.

It is only a matter of time before a large assortment of genetic variations which contribute to criminality are identified. Once we reach that point I see a few issues coming up as a result:

  • When felons with genetic traits that increase criminality have kids should their kids get tested both to assess their odds of future criminal activity and also to have them in databases to match against future crime scenes? Ditto fingerprints for matching against crime scenes.
  • Should the genetically criminal have the right to reproduce? How strong should a person's genetic predisposition to criminality have to be before they lose the right to reproduce? Suppose they have a 50% odds of being a rapist or murders due to some genetic variations. Should they have the right to have kids?
  • Alternatively, once we know the genetic variations that contribute to criminality should the genetically criminal be required to reproduce using in vitro fertilization (IVF) with pre-implantation genetic diagnosis (PGID or PGD) where embryos are that do not contain the worst crime genes?
  • Should it be legal to use the DNA samples of criminals against their will in order to do sequencing studies to identify genetic variations that contribute to criminality?
  • Should felons with strong genetic predispositions to criminality be required to get a vasectomy or tubes tied as a condition of parole?

I see the classic arguments for individual rights as being first cut approximations of reality. Some people are greatly deficient in the capacity and desire to respect the rights of others. If we can detect them before they violate rights or can more easily identify them after they violate rights then I'm all for it. We are not born equal in our willingness and capacity to respect rights. Therefore we are not born equal in rights of our own.. It is a pretty myth to say we are. But it is also a damaging myth. The myth is going to become increasingly hard to defend against sicentific advances.

By Randall Parker 2006 May 11 09:02 PM  Bioethics Privacy
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2006 May 09 Tuesday
Women Can Detect Child Friendliness In Male Faces

Women are wired up to detect which men like children.

(Santa Barbara, CA) – Women are able to subconsciously pick up cues in men's faces and use those cues to determine if they are attracted to the males for long-term or short-term relationships, according to a new study conducted by researchers at the University of California, Santa Barbara and the University of Chicago.

The study was published online today by the Proceedings of the Royal Society of London, the UK's national academy of science.

Men whose faces reflected an interest in children were intuitively perceived by woman as candidates for long-term commitments, whereas men whose faces indicated high testosterone levels were determined to be short-term prospects for relationships.

"Women are surprisingly accurate in being able to determine interest in children and testosterone levels," said James Roney, assistant professor of psychology at the University of California, Santa Barbara, who is the lead author of the paper. "Our data suggest that men's interest in children predicts their long-term mate attractiveness even after we account for how physically attractive the women rated the men," he said.

For the study, the researchers recruited male undergraduate students from a variety of ethnic backgrounds who were tested for testosterone and for their interest in children.

Researchers took saliva samples to measure testosterone levels. To determine interest in children, researchers showed the men a pair of pictures, one each of an adult and a baby. They were then asked which picture they preferred. Slightly more than twelve percent of the men expressed no interest in the baby pictures, while the rest expressed a range of interest, up to nine out of ten preferences for the infants.

The researchers then took pictures of each man, asking them to display a neutral expression. An oval frame was placed around each photo to focus attention on the faces and the photos were shown to undergraduate women from diverse backgrounds at UCSB.

The women were asked to rate the men according to whether they thought the men liked children, whether they appeared masculine, physically attractive, or kind. They were then asked to determine men's attractiveness as short-term romantic partners or as long-term partners for relationships such as marriage.

The men chosen as being most interested in children were also the same men who had expressed the most interest in children in the photo test. The women were also able to determine from their photos which men had high testosterone levels because they perceived the men as looking masculine.

Although women said they were attracted to the men who tested high for testosterone, an important factor in their attraction to men for a long-term relationship was their perception of a man's affinity for children, even after accounting for their perceptions of men's general kindness.

"The research suggests that men's interest in children may be a relatively under-appreciated influence on men's long-term mate attractiveness," Roney said.

What I'd like to see: Test women for estrogen levels and body shapes and see if the more feminine women are better or worse at detecting which men are more child-friendly. I bet the higher estrogen or perhaps high estradiol women are better at identifying good mates.

Also, are higher testosterone men more likely to get divorced?

By Randall Parker 2006 May 09 11:11 PM  Brain Sexuality
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Lesbian Brains Respond Differently To Pheromones

Using positron emission tomography (PET) and Magnetic Resonance Imaging (MRI) Swedish researchers have found that the brains of homosexual women responded to pheromones in ways more like heterosexual men than like heterosexual women.

Lesbian and heterosexual women respond differently to specific human odours, a brain-scanning study has found. The homosexual women showed similar brain activity to heterosexual men when they inhaled certain chemicals, which may be pheromones, the researchers say.

"But our study can't answer questions of cause and effect," cautions lead researcher Ivanka Savic at the Karolinska Institute in Stockholm, Sweden. "We can't say whether the differences are because of pre-existing differences in their brains, or if past sexual experiences have conditioned their brains to respond differently."

Anyone surprised?

They used two candidate human pheromones labelled "AND" and "EST" and found that lesbian brains responded more like heterosexual male brains.

Lesbian and heterosexual women showed different patterns of brain activity while sniffing AND and EST, the study shows.

While smelling AND and EST, the brain activity pattern for lesbian women was closer to that of heterosexual men than heterosexual women, Savic and colleagues note.

Previously homosexual men and heterosexual women were found to have even greater similarity in their brain patterns when exposed to these compounds.

Lesbians didn't react in their anterior hypothalamus while heterosexual women did.

The results showed that while a part of the brain called the anterior hypothalamus -- which is linked to sexual behavior, among other things -- tended to light up in the straight women, the lesbians showed no reaction.

On the other hand, lesbians tended to react to male as well as female hormones in the part of the brain that handles routine odors.

We have preferences and desires that come up from deep in our subconsciouses which we have little control over. We have some control over how we react to the desires. But little control over the nature of the actual desires.

By Randall Parker 2006 May 09 10:48 PM  Brain Sexuality
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2006 May 08 Monday
Slight Calorie Restriction Might Deliver Longer Life

Even a small decrease in calorie consumption delivered lower signs of age-related oxidative stress in rats.

GAINESVILLE, Fla., - A lifelong habit of trimming just a few calories from the daily diet can do more than slim the waistline - a new study shows it may help lessen the effects of aging.

Scientists from the University of Florida's Institute on Aging have found that eating a little less food and exercising a little more over a lifespan can reduce or even reverse aging-related cell and organ damage in rats.

The discovery, described this month in the journal Antioxidants and Redox Signaling, builds on recent research in animals and humans that has shown a more drastic 20 percent to 40 percent cut in calories slows aging damage. The UF findings indicate even small reductions in calories could have big effects on health and shed light on the molecular process responsible for the phenomenon, which until now has been poorly understood.

"This finding suggests that even slight moderation in intake of calories and a moderate exercise program is beneficial to a key organ such as the liver, which shows significant signs of dysfunction in the aging process," said Christiaan Leeuwenburgh, Ph.D., an associate professor of aging and geriatric research at the UF College of Medicine and the paper's senior author.

UF scientists found that feeding rats just 8 percent fewer calories a day and moderately increasing the animals' activity extended their average lifespan and significantly overturned the negative effects of cellular aging on liver function and overall health.

An 8 percent reduction is the equivalent of a few hundred calories in an average human diet and moderate exercise is equivalent to taking a short walk.

But most people can't reduce their calorie consumption at all for a sustained length of time. So this is an interesting result and a reason to eat slightly less. But few will manage to pull that off.

The researchers also found that RNA is an earlier biomarker for aging than DNA.

To reveal the workings of the body's chemical climate when aging-related damage happens, UF researchers tracked levels of biomarkers - chemicals and molecules present in the liver - in groups of rats. The liver, a crucial organ for maintaining good health during aging, cleans the blood and helps regulate the body's immune system. The researchers also plan to assess the same biomarkers in a study of rats' hearts, muscle and brains.

The research team was surprised to find one of the biomarkers, RNA, which is important for coding DNA and for protein synthesis, is more quickly damaged by aging than the more frequently studied DNA. RNA damage, therefore, could be an excellent early signal to indicate the onset of aging, researchers say.

"Because it is more sensitive to oxidative stress, RNA can be useful as an early marker of oxidative damage and even aging," said Arnold Y. Seo, a doctoral student in UF's Institute on Aging.

Better aging biomarkers that detect changes at earlier stages allow more rapid testing of potential life extending therapies.

Another study on rats found important clues for how calorie restriction lengthens life expectancy. Mice lacking a growth hormone receptor and with lower resulting insulin live longer than normal mice.

"The implication ... for pharmaceutical development would be that the signaling pathways of growth hormone and insulin may be logical targets for development of anti-aging medicine," Dr. Andrezej Bartke from Southern Illinois University in Springfield told Reuters Health.

...

However, in sharp contrast to its effects in normal mice, calorie restriction failed to increase lifespan in mutant mice lacking growth hormone receptor. "The present findings show that growth hormone resistant mice fail to respond normally to calorie restriction, a very effective life-extending intervention," Bartke said.

I think the idea here is that the reduction in growth hormone receptor delivers the life extension benefit that calorie reduction would normally deliver. So when calories are reduced in these mice there is not an additional benefit from the calorie reduction.

Update: You can read the paper in the Proceedings of the National Academy Of Science by Bartke's group in abstract and the full paper in open access.

By Randall Parker 2006 May 08 10:35 PM  Aging Diet Studies
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2006 May 07 Sunday
English Middle Aged More Healthy Than Americans

A RAND Corporation study finds that middle-aged people in the United States are sicker than middle-aged people in England.

Middle-aged Americans are less healthy than their English counterparts, according to a study issued today by researchers from the RAND Corporation, University College London and the Institute for Fiscal Studies in London.

Analyzing surveys of large groups of middle-aged people from the United States and England, researchers found that Americans ages 55 to 64 suffer from diseases such as diabetes, high-blood pressure and lung cancer at rates up to twice those seen among similar aged people in England.

The prevalence of diabetes was twice as high in the United States (12.5 percent) as compared to England (6.1 percent), while high blood pressure was about 10 percentage points higher in the United States than in England. Heart disease was 50 percent more common among middle-aged Americans than the English, while the rates of stroke, lung disease and cancer were higher among Americans as well.

The differences were confirmed when researchers analyzed separate studies that collected blood samples from participants to look for biological markers of disease. This showed that the differences were not just a result of Americans' increased willingness to report illness.

The study appears in the May 3 edition of the Journal of the American Medical Association.

“You don't expect the health of middle-aged people in these two countries to be too different, but we found that the Americans are a lot less healthy than the English,” said James P. Smith, a RAND economist and one of the study's authors. “It's not just a difference in how people characterize their own health. The biological measures confirm there is a difference.”

Reports of poorer health were seen across all economic groups in the United States in comparison to their English peers, not just among the poor who are generally seen as having more health problems.

Except for cancer, people with less income and education in both of the nations were more likely to report being sick than those with more income and education. Because of the differences between the two nations, those at the top of the education and income scale in the United States reported rates of diabetes and heart disease that were similar to those at the bottom of the scale in England.

One can't attribute this difference to a lack of access to health care in the United States because those with much more education and income in the US did about as well as those at the bottom did in England.

Researchers were concerned that any differences in health might be blamed on the higher rates of illness seen among Latinos and African-Americans in the United States, so the study included only non-Hispanic Caucasians in both countries.

Researchers say that the differences in health between the two nations is not fully explained by lifestyle factors, including smoking, drinking, excess weight and poor exercise. Smoking behavior is similar in the two nations, while excessive drinking of alcohol is more common in England.

Obesity is more common in the United States and Americans get less exercise, according to the study. But researchers estimate that those factors account for less than half of the differences seen between middle-age people from the United States and England.

The more recent rise in obesity in England means that fat people there, on average, haven't been as fat for as long as similarly fat people in the United States. This would account for the higher rates of heart disease and diabetes in the United States. More accumulation of years of being overweight gives more time for the effects of the obesity to be felt in insulin metabolism and the circulatory system.

Researchers say that past differences in health risk factors may be one explanation for the disparities seen in the middle-aged people covered by the study.

Rising obesity has occurred in the United Kingdom only recently, with the incidence increasing from 7 percent in 1980 to 23 percent in 2003. Meanwhile, the prevalence of obesity in the United States rose from 16 percent to 31 percent during the same period.

“It may be that America's longer history of obesity or differences in childhood experiences create the problems seen among middle-aged Americans,” said study co-author James Banks, an economist at University College London. “This may mean that over time the gap between England and the United States may begin to close.”

This suggests that health of the middle aged will decline in Britain in coming decades with more heart disease and diabetes.

The growing popularity of statin drugs to control cholesterol combined with the development of other drugs to fight obesity and type II insulin-resistant diabetes will eventually reverse this trend.

By Randall Parker 2006 May 07 07:09 PM  Aging Studies
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Pandemic Influenza Costs Estimated

Health economist Martin Meltzer of the US Centers for Disease Control and Prevention says depending on the severity of the strain an influenza pandemic's cost would range between tens of billions and trillions of dollars.

According to a 1999 study by Meltzer and colleagues, a flu pandemic where 35% of people are attacked by the virus would cost the US alone a total of $166 billion. A milder 1968-like pandemic, with only a 15% attack rate, would cost the US $71 billion. He notes that these are “conservative” estimates and do not account for work days lost due to panic or parents staying home with their children because schools are shut.

However, he points to a recent study by an Australian economist which models the impacts of scenarios from mild to an “ultra-1918” type pandemic. In this worst case scenario, the cost to the world could run into trillions of dollars.

Ideally if one could estimate the probability of each type of pandemic then could multiply that probability times the total estimated cost to get a sense of the value to be gained from developing methods to stop or decrease the severity of a pandemic. But for a repeat of the 1918 severity pandemic or something even more deadly it is hard to come up with a reasonable probability for its occurrence.

Meltzer compares bird flu to the SARS outbreak that encompassed a much smaller number of companies and thinks once the pandemic passes the economy will recover very rapidly.

The biggest impact of an influenza pandemic, which would likely last less than four months depending on the size of the countries affected, would probably hit growth for just one to two quarters, Meltzer said.

"After that, I expect to see a great rebound," he said. "People will return and we will see normal growth rates."

A more lethal strain would leave more lasting effects because it would shrink the population and cause decreased demand for housing. Plus, the problem of handling so many wills and estates would slow the changing of ownership of assets of the deceased.

The World Bank has yet another cost estimate but it is unclear what level of lethality they assumed for this estimate.

The World Bank has estimated a yearlong flu pandemic would cost the world economy US$800 billion. That's nearly 27 times the cost of SARS, which was estimated at US$30 billion, according to the World Health Organization.

Anyone know what sort of flu strain they assumed in their model?

By Randall Parker 2006 May 07 06:57 PM  Pandemic Prepare Business
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2006 May 06 Saturday
Discoveries Point Way To Mow-Less Lawns?

The best known ways we reduce the amount of work humans do is by developing equipment that automates a task. That approach tends be much more visible than other methods for eliminating human work because we can see the automated equipment at work in factories and other work settings. But a far more powerful and less appreciated way to raise living standards is to reduce or even entirely eliminate the need to perform a task in the first place.

While some argue about the difficulty of developing totally automated lawn mowers a better way to eliminate the need for human labor in lawn mowing is to genetically engineer lawn grass to grow to a fixed lower maximum height. Recent discoveries about the brassinosteroids in plants point the way toward lawn grass that doesn't grow as tall and does not have to be mowed.

For anyone tethered to a lawnmower, the Holy Grail of horticultural accomplishment would be grass that never grows but is always green.

Now, that vision of suburban bliss—and more—seems plausible as scientists have mapped a critical hormone signaling pathway that regulates the stature of plants. In addition to lawns that rarely require mowing, the finding could also enable the development of sturdier, more fruitful crop plants such as rice, wheat, soybeans, and corn.

In a paper published in the May 4, 2006, issue of the journal Nature, Howard Hughes Medical Institute scientists report they have deciphered the signaling pathway for a key class of steroid hormones that regulates growth and development in plants.

"By manipulating the steroid pathway…we think we can regulate plant stature and yield," said Joanne Chory, a Howard Hughes Medical Institute investigator at the Salk Institute for Biological Studies, and the senior author of the new report.

Manipulation of plant stature has been a longstanding goal in horticulture, agronomy, and forestry. The ability to precisely control plant size would have broad implications for everything from urban forestry to crop and garden plant development. Beyond perpetually short grass, trees could be made more compact for better growth in crowded cities, and berry bushes could be made taller for ease of harvesting.

Imagine future spray-on gene therapy treatments where once you get your hedges shaped just like you want it you spray the hedges once and they cease to extend new branches for a couple of years. No more need for hedge pruning.

Genetic engineering of regulatory regions in the brassinosteroid pathway might be the ticket for producing mow-free lawn grasses.

"We might be able to dwarf grass and keep it green by limiting brassinosteroids or increase the yield of rice by having more brassinosteroids in seeds," Chory said.

Biotechnological advances will provide ways to grow food in backyard gardens with less labor while also cutting back on yard labor.

What is the best way to reduce the labor for ironing clothes? Make automated ironing machines? Of course not. Make clothes that do not need ironing. What is the best way to reduce the labor needed for home repair? Develop robots? Again, of course not. Make building materials that last decades longer. What is the best way to keep cars clean? Develop automated cleaning machines? No, make surfaces with nanomaterials that dirt can't stick to or surfaces that can clean themselves. Advances in nanotechnologies and biotechnologies will provide us with lower maintenance textiles, cars, houses, lawns, and other items we use in our daily lives.

By Randall Parker 2006 May 06 08:56 PM  Biotech Automation
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2006 May 04 Thursday
Genetically Engineered Viruses Selectively Kill Cancer Cells

A genetically engineered virus selectively kills cancer cells.

An engineered virus tracks down and infects the most common and deadly form of brain cancer and then kills tumor cells by forcing them to devour themselves, researchers at The University of Texas M. D. Anderson Cancer Center report this week in the Journal of the National Cancer Institute.

The modified adenovirus homed in on malignant glioma cells in mice and induced enough self-cannibalization among the cancer cells - a process called autophagy - to reduce tumor size and extend survival, says senior author Seiji Kondo, M.D., Ph.D., associate professor in the Department of Neurosurgery at M. D. Anderson.

"This virus uses telomerase, an enzyme found in 80 percent of brain tumors, as a target," Kondo says. "Once the virus enters the cell, it needs telomerase to replicate. Normal brain tissue does not have telomerase, so this virus replicates only in cancer cells."

Other cancers are telomerase-positive, and the researchers showed in lab experiments that the virus kills human prostate and human cervical cancer cells while sparing normal tissue.

Note that the viruses used in this experiment really are a form of gene therapy. The virus coating delivers a genetic payload into cells. The genes have been arranged to activate only in cancer cells.

I expect we will see two major categories of cancer cures using gene therapy. First, gene therapies will selectively activate and kill only cancer cells. The genes will be engineered to operate only in conditions that are found only in cancer cells or rarely in non-cancer cells. Second, other gene therapies will repair the mutated genes in cancer cells that are causing the cells to divide out of control.

A cancer cell is like a self-modifying computer program that has accidentally changed itself to malfunction in a very dangerous way. We need to either fix the program by sending in program parts to replace the damaged parts or we need to send in another program that only activates and kills when it finds itself inside a cell that is out of control. Gene therapy strikes me as the best solution to cancer because it can be far more exact than toxic drugs.

By Randall Parker 2006 May 04 10:50 PM  Biotech Cancer
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2006 May 03 Wednesday
Prospect Of Rewards Triggers Memory Formation

Reward-related areas of the brain tell other areas of the brain when events should have memories created for them.

The prospect of a paycheck, good grade, or promotion wonderfully concentrates the mind, and researchers have now identified the brain circuitry responsible for such reward-motivated learning.

In an article in the May 4, 2006, Neuron, Alison Adcock and colleagues report brain-scanning studies in humans that reveal how specific reward-related brain regions "alert" the brain's learning and memory regions to promote memory formation.

In their studies, the researchers asked volunteers to participate in two types of reward-related tasks as they scanned the subjects' brains using functional magnetic resonance imaging. In this technique, harmless magnetic fields and radio waves are used to detect regions of higher blood flow in the brain, which reflects higher activity.

In the first task, the researchers aimed at identifying the region involved in anticipating rewards. This task involved presenting the subjects with such symbols as circles or squares that indicated an amount of money the subjects could gain or lose--from no money to $5--by rapidly responding to a subsequently presented target by pressing a button. The subjects were notified immediately whether they had received the reward. The researchers found that reward anticipation activated specific brain structures in the "mesolimbic" region involved in the processing of emotions.

In the second task, the researchers sought to measure how this reward center promoted memory formation. They first showed subjects a "value" symbol that signified whether the image of a scene that followed would yield $5 or ten cents if they remembered it the next day. Then they showed the subjects the scene, and the next day tested their ability to pick the scene out of a group.

The researchers found that the subjects were far more likely to remember high-value scenes than low-value scenes. Importantly, they found that the cues to the high-reward scenes that were later remembered--but not those scenes later forgotten--activated the reward areas of the mesolimbic region as well as the learning-related hippocampus in the medial temporal lobe (MTL) of the brain. Activation prior to scene visualization suggests that the brain actually prepares in advance to filter incoming information rather than simply reacting to the world. Activation of the MTL is associated with higher brain functions, including learning and memory, and subjects who showed greater activation in these regions also showed better memory performance, found Adcock and colleagues.

The researchers concluded that the learning mechanism they identified "may let an organism's expectations and motivation interact with events in the physical world to influence learning. Thus, anticipatory activation of this mesolimbic circuit may help translate motivation into memory."

One of the problems with childhood education is that it seems so distant to eventual rewards in the job marketplace. If schools and parents could find better ways to reward better school performance the average kid in school might spend more time with their medial temporal lobe (MTL) activated and forming memories.

One problem with reward systems is that kids differ greatly in their ability to learn. How to gear a reward system to toward the abilities of each kid so that rewards are geared toward the upper range of how fast they can learn without having the rewards set too high so that the level of performance needed for rewards becomes unattainable for some kids or too easy for other kids?

Also, there's something to be said for a practice that I and many others to do themselves: Reward yourself for achieving some learning goal. When you set rewards for yourself to strive for you are setting up the conditions to active your brain's MTL.

By Randall Parker 2006 May 03 10:12 PM  Brain Economics
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2006 May 02 Tuesday
Most American Corporations Expect Flu Pandemic

American companies expect a more lethal influenza strain to break out into the human population. But they aren't doing enough to prepare.

More than half of U.S. companies think there will be a global flu epidemic in the next two years. Two-thirds think it will seriously disrupt their operations as well as foment social unrest. But two-thirds also say they aren't prepared. One-third of executives surveyed say nobody in their organization has been appointed to plan for a pandemic; another one-quarter couldn't or wouldn't answer the question.

"Corporations are looking at this like deer at headlights," said Tommy G. Thompson, who spent much of his last two years as secretary of health and human services sounding the pandemic alarm and is now doing the same as a private consultant. "They are very skittish. They don't know which way to go. They are hoping the car is not going to hit them."

Some parts of SAIC are ready to shift toward telecommuting.

On a Saturday two months ago, SAIC tested its telecommuting capability with a unit that operates in Northern Virginia, Hawaii and several foreign countries to see whether everyone could work outside the office with all necessary functions, programs and communications. Several software problems arose.

Preparations for a massive shift to telecommuting would help a great deal. But for facilities which require people on-site (e.g. power plants, factories, warehouses, rail yards) I promote an approach I call workplace cocooning. Have a group of workers quarantine themselves into a factory or warehouse or computer facility with futons to sleep on, refrigerators, microwaves, and other gadgets to make the place suitable for staying in for weeks and months without leaving and without direct contact with humans outside the facility. Methods could be developed for bringing parts in and shipping finished products out without humans from the outside coming into direct contact with those inside.

Since tourism will collapse lots of hotels will sit empty. Well, hotels make good candidates to be turned into quarantined live-in office buildings. White collar teams that need to work together in person could move into hotels with their computers and other needed equipment. Then they'd isolate themselves from the outside except to receive packages delivered and left at the door for their later retrieval.

Many types of businesses could rapidly restructure to eliminate long chains of exposure via which viruses can spread. Telecommuting and workplace cocooning could allow the economy to function while greatly reducing the ability of a pandemic influenza virus to spread into company workforces.

By Randall Parker 2006 May 02 10:24 PM  Pandemic Prepare Business
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2006 May 01 Monday
Berkeley Group Puts DNA Sequencer On Chip

UC Berkeley chemistry professor Richard A. Mathies along with his Ph.D. candidates Robert G. Blazej and Palani Kumaresan have taken the standard Sanger process for DNA sequencing and shrunk a DNA sequencer down to a chip.

The upshot, Mathies says, is that the chips' small size and integration should reduce reagent and personnel costs to the point where it should be possible to sequence a complete genome for as little as $50,000. Mathies, whose team publishes its work online this week in Proceedings of the National Academy of Sciences, says UC Berkeley has licensed patents on the technology to Microchip Biotechnologies of Dublin, California.

They've combined all the steps on a chip.

The hand-held device is able to combine these three main sequencing steps – thermal cycling (to generate the different length DNA strands); sample purification; and capillary electrophoresis – into a single automated process. The size of the device means it requires a fraction of the expensive chemical reagents normally needed for DNA sequencing, greatly reducing the running costs.

Small means cheap. The smaller the cheaper.

Here's the abstract of the PNAS paper:

An efficient, nanoliter-scale microfabricated bioprocessor integrating all three Sanger sequencing steps, thermal cycling, sample purification, and capillary electrophoresis, has been developed and evaluated. Hybrid glass-polydimethylsiloxane (PDMS) wafer-scale construction is used to combine 250-nl reactors, affinity-capture purification chambers, high-performance capillary electrophoresis channels, and pneumatic valves and pumps onto a single microfabricated device. Lab-on-a-chip-level integration enables complete Sanger sequencing from only 1 fmol of DNA template. Up to 556 continuous bases were sequenced with 99% accuracy, demonstrating read lengths required for de novo sequencing of human and other complex genomes. The performance of this miniaturized DNA sequencer provides a benchmark for predicting the ultimate cost and efficiency limits of Sanger sequencing.

Here's the company which is commercializing the UC Berkeley work:

Microchip Biotechnologies Inc. (MBI) has been formed to commercialize leading-edge microfluidic and nanofluidic sample preparation technologies for the DNA sequencing, biodefense, and other life sciences applications. Founded in July 2003 by leaders in the field of life science instrumentation who helped create the genomics revolution and by leaders in microfluidics, MBI is developing breakthrough patent-pending nanofluidic technologies into products that meet the needs for high-quality nanoscale sample preparation.

Based in part on technologies exclusively optioned from the University of California at Berkeley, MBI is creating a product platform to produce a family of scaleable NanoBioProcessor™ products that perform sample preparation as a front-end for existing and future analytical instruments. The NanoBioProcessor™ will introduce mini-robotics with on-chip nanofluidic processing controlled by on-chip MOV™ valves and pumps. This novel technology to create arrays of valves and pumps has the potential to revolutionize fluidics and make complex devices manufacturable and affordable. MBI is also developing bead-based technologies to capture and purify biological materials before on-chip bioprocessing.

With so many academic and commercial research groups trying to drive down the cost of DNA sequencing by orders of magnitude and with so many demonstrating promising technologies the days of high priced DNA sequencing look to be short-lived.I'll be surprised of DNA squencing for a person costs more than $10,000 10 years from now.

Really cheap DNA sequencing will lead to massive comparisons of DNA sequence differences between people in combination with large numbers of details collected about each person. Medical histories, life histories, IQs, personality tests, and other measures of each person will get compared in combination with their DNA sequences in order to identify all the genetic variations that cause differences in who we are.

By Randall Parker 2006 May 01 10:06 PM  Biotech Advance Rates
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