Sunday, April 30, 2006
Climate opportunists never miss an opportunity to mislead society.
On 15 April, the River Danube reached its highest level for some 111 years, forcing residents of Romania, Bulgaria, Hungary and Serbia to flee their homes. With weeks of snowmelt and rain swelling Europe's second-longest river, the waters haven't dipped below that level since. Meteorologists are warning that the flood represents yet more evidence that climate change is gearing up to play havoc with our weather. . .
Some might say the flooding was down to bad luck more than anything else. Spring hit Europe quite quickly this year, after a relatively long period of winter cold. Temperatures rose by some 15°C over the space of a week in some parts of the Alps, leading to massive snowmelts. This led to two large surges along the Danube itself and in one of its main tributaries, the Tisza. In a freak coincidence, both of these flood waves arrived in the lower Danube together, at the same time as a long period of persistent rain. . .
Single events are notoriously difficult to attribute to shifting climate rather than random chance. This is particularly the case for natural disasters involving precipitation — rain and snowfall — which tends to fluctuate more capriciously than temperature. Nevertheless, some experts say that this is a sign of what's in store. "While no single event can be attributed to climate change, the Danube scenario represents the kind of event that is likely to become more frequent according to climate-change predictions," says David Crichton, a climate expert based in Inchture, Scotland.
What a weasel. No, this wasn't caused by climate change. Using events like these as publicity for theories based on dodgy models is not just reprehensible, it is actively harmful to society. We would do well to discover ways to hold individuals like this responsible for the harm they do. In any case, this event is contrary to climate change theory.
But with warming climate comes a reduction in the amount of snow on mountaintops, which might mean that spring floods — such as this Danube event — might actually become less commonplace.
Might, might ... It's interesting to contrast the definite assertions of the climate hysterics with the tentative contradiction of those who read the book.
Wednesday, April 26, 2006
One of the issues I've been paying more attention to is the large and increasing number of boys that fall off the formal education wagon, and so are often doomed to a life of poverty, insecurity and exclusion. Too many end up as social problems: our jails are filled and the percentage of men that do time, especially black men, is a scandal.
A number of thinkers, commenters and researchers have lately been noting that our educational system creates an increasingly hostile environment for boys. This paper is another in the group:
"We found very minor differences in overall intelligence. But if you look at the ability of someone to perform well in a timed situation, females have a big advantage," Camarata said. "It is very important for teachers to understand this difference in males and females when it comes to assigning work and structuring tests. To truly understand a person's overall ability, it is important to also look at performance in un-timed situations. For males, this means presenting them with material that is challenging and interesting, but is presented in smaller chunks without strict time limits."
The findings are particularly timely, with more attention being paid by parents, educators and the media to the troubling achievement gap between males and females in U.S. schools.
"Consider that many classroom activities, including testing, are directly or indirectly related to processing speed," the authors wrote. "The higher performance in females may contribute to a classroom culture that favors females, not because of teacher bias but because of inherent differences in sex processing speed." An additional question is whether this finding is linked to higher high school dropout rates for males and increased special education placement for males that do stay in school. . .
"'Processing speed' doesn't refer to reaction time or the ability to play video games," Camarata said. "It's the ability to effectively, efficiently and accurately complete work that is of moderate difficulty. Though males and females showed similar processing speed in kindergarten and pre-school, females became much more efficient than males in elementary, middle and high school."
The researchers found that males scored lower than females in all age groups in tests measuring processing speed, with the greatest discrepancy found among adolescents. However, the study also found that males consistently outperformed females in some verbal abilities, such as identifying objects, knowing antonyms and synonyms and completing verbal analogies, debunking the popular idea that girls develop all communication skills earlier than boys.
The researchers found no significant overall intelligence differences between males and females in any age groups.
The researchers hope to discover more about the physical basis of these differences. We are discovering ever more ways that brains vary by sex.
If you want to get noticed you must be controversial. You can do that by being more shrill than fellow travelers or by loudly beating your way through the bush to blaze a new trail. George Monbiot has tried the former and now seems to be trying the latter. [via Envirospin Watch]
. . . the British government is even more likely to recommend a new generation of nuclear generators in its energy review in the summer. It can now summon some heavyweight support: on Friday, the Financial Times revealed that the International Energy Agency has converted to the nuclear cause. My fellow environmentalists argue that the money would be better spent on wind turbines. I find myself at odds with almost everyone, by deciding, at the worst possible moment, that in one respect at least our battle against climate change depends on neither nuclear power nor renewables, but on a fossil fuel. . .
. . . a hydrogen network will be viable only if it is cheap. According to a report by the US National Academy of Engineering, the wholesale price of hydrogen made from natural gas with carbon capture will, in "the future", be $1.72 (96p) per kilogramme; from coal, $1.45; and from electrolysis $3.93. In other words, if a hydrogen economy is to be taken seriously, the fuel has to be made from gas or coal, rather than by either wind turbines or nuclear generators.
Even in my confessional mood, I cannot bring myself to support coal. I defy anyone who knows what open-cast mining looks like to say the words "clean coal" without blushing. This leaves only gas. If my calculations are correct, the retail price of hydrogen made from natural gas will be about 50% greater than the retail price of gas itself. But because fuel cells supplying both heat and electricity are more efficient than gas boilers, the total cost would be roughly the same.
And achieve nothing of value. It's another hide-the-pea scheme to avoid what seems to be an inevitable increase in the use of nuclear power, at least as an interim step to some future energy technology such as greatly enhanced solar PV cells. Though it may be that the future technology at the other end of the nuclear bridge is also nuclear since there are new designs that are claimed to be much cheaper to operate through their whole life cycle - from construction to decommissioning - as well as being far safer and less subject to monkey-wrenching. It's a family of technologies that have been scandalously neglected for a couple of decades due to mass psychosis, and I expect some interesting developments in the not too distant future now that interest and research funding is beginning again. One of the most attractive aspects of interest in nuclear energy in the developing world is that they have far fewer fussy inhibitions about thinking nuclear thoughts.
Saturday, April 22, 2006
brutish behavior ratified by procedure
The purpose of a university, Mr. Westhues contends, is to maintain a spirit of openness, independence of mind, and civil debate. "A university cannot achieve its purpose as a tight ship," he says. When a mobbing occurs, that spirit of openness gets strangled by groupthink, bent on someone's elimination.
The Law of Group Polarization, formulated by Cass R. Sunstein, a law professor at the University of Chicago, says that a bunch of people who agree with each other on some point will, given the chance to get together and talk, come away agreeing more strenuously on a more extreme point. If this tendency has a curdling effect on intellectual debates, it can have a downright menacing effect when the point of agreement is that a particular colleague is a repugnant nutjob. . .
anything that can be a basis for bickering can be a basis for mobbing: race, sex, political difference, cultural difference, intellectual style. Professors with foreign accents, he says, often get mobbed, as do professors who frequently file grievances and "make noise." But perhaps the most common single trait of mobbing targets, he says, is that they excel.
The nail that sticks up gets hammered down.
Wednesday, April 19, 2006
Brad Allenby explains that part of Phoenix Environmentalism: Part I and Part II is:
It means accepting that humans will continue to impact evolutionary biodiversity, while creating designed biodiversity in companies and laboratories; that the world's ecosystems will change profoundly as a result of human activity; that more technology, not less, will characterize the world.
This isn't just old species going extinct to be replaced by laboratory creations, it also means evolution to adapt to human environments.
Evolution is operating with a vengeance in the urban environment as animals struggle to adapt to novel conditions and cope with "evolutionary illusions".
An animal is said to be in an evolutionary illusion or trap when it does something it has evolved to do, but at the wrong time or in the wrong place. The concept may help explain why so many squirrels get squashed on city streets, says Brown. For millions of years, squirrels have evolved to cross open spaces as quickly as possible, without wasting time watching for predators that they would not be able to escape anyway. "Ordinarily, that was a very sensible thing to do," he says. "But as an urban squirrel crossing four lanes of traffic, that's a bad idea."
Though ecologists used to dismiss urban areas as unworthy of study, they have recently begun to realise that cities provide an ideal theatre in which to see behaviour evolving at a pace rarely seen in the wild. City environments tend to be less variable than the countryside. Urban heat islands mean that insects can be active longer or throughout the year, and human activity provides urban wildlife with more stable, predictable sources of food and water.
It's a struggle but that's life. That has always been life. The field of adaptation is changing fast so evolution is in high gear. There is blood on the tracks, and road kill, but it also seems that there are survivors. There is a lot of worry that the pace is too fast, that many species will not be able to adjust so quickly. I suspect that this is true. Moreover, the reduced variability of developed environments seems that it would not reward great diversity, but I'm not sure how that works.
Wednesday, April 12, 2006
When it was recently discovered that plants emit methane I lamented that everything I know is wrong. One after another all my solid bits of knowledge turn out to be nonsense as new discoveries are made. The good scientist is happy when this happens, happy to have better information, comforted by the march of progress or something. I try, but it isn't comfortable, it's irritating. I have to take myself out behind the wood shed sometimes for a bracing lecture on the method and how this is all to the good. It happened again.
Until recently it was generally believed that the most important source of nitrogen for plants was inorganic nitrogen. However, researchers funded by the Biotechnology and Biological Sciences Research Council (BBSRC) from the University of Lancaster and the Institute of Grassland and Environmental Research (IGER) have found that not only can organic nitrogen be directly taken up by plants it is also used differently by different species, enabling nitrogen sharing and biodiversity.
By tagging organic nitrogen with stable isotopes researchers have challenged the long held idea that organic nitrogen has to be first converted into an inorganic form before the plants can use it. Their findings have significant implications in unfertilised, low-productivity grasslands where organic nitrogen often appears in greater concentrations than inorganic forms.
Professor Richard Bardgett, lead researcher at the University of Lancaster explained: "This research provides important new information about what happens to organic nitrogen in real ecosystems in real time. Tagging amino acids also revealed that different plant species prefer different sources of organic nitrogen. These preferences may be a way for plants and microbes to avoid competition with their neighbours for nitrogen when it is in very short supply, effectively enabling them to share nitrogen and maintain biodiversity."
This is just a brief press release. There's no useful detail, and the focus at the Institute of Grassland and Environmental Research (IGER) is on untilled swards, but it would seem that there are also implications for cropped lands that seek to amend soils using organic matter. If different plant species prefer different sources of organic nitrogen then a grower would want to match sources to crop species for best effects.
Update:
gaaahh! It seems that we also have anaerobic oxidation of methane.
Why did it take until now to identify this process? The main reason is probably that it proceeds at much lower rates than the anaerobic oxidation of other organic compounds or of hydrogen sulphide with nitrate. So the process is evident only in anoxic environments with low concentrations of oxidizable substrates other than methane, and with low levels of sulphate and high levels of nitrate. Such conditions prevail in anoxic freshwater habitats contaminated with agricultural run-off and in contaminated groundwater. The nitrate-dependent anaerobic oxidation of methane is predicted to occur mainly close to the oxic–anoxic interface, where in the oxic phase ammonia is oxidized to nitrate with oxygen by nitrifying (nitrate-forming) microorganisms. Nitrate then diffuses into the anoxic sediments saturated with methane, which is produced microbially from the degradation of cellulose and other plant material (Fig. 2). The interface is generally characterized by steep chemical gradients, which occur within millimetres and mask the process of the anaerobic oxidation of methane with nitrate.
Monday, April 10, 2006
I sometimes think that degrees are prizes found in boxes of high fructose children's breakfast cereal. This paper makes me suspicious.
Plants apparently do much less than previously thought to counteract global warming, according to a paper to be published in next week's online edition of Proceedings of the National Academy of Sciences.
The authors, including Bruce Hungate of Northern Arizona University and lead author Kees-Jan van Groenigen of UC Davis, discovered that plants are limited in their impact on global warming because of their dependence on nitrogen and other trace elements. These elements are essential to photosynthesis, whereby plants remove carbon dioxide, a greenhouse gas, from the air and transfer carbon back into the soil.
"What our paper shows is that in order for soils to lock away more carbon as carbon dioxide rises, there has to be quite a bit of extra nitrogen available--far more than what is normally available in most ecosystems," said Hungate of NAU's Merriam-Powell Center for Environmental Research.
The paper notes that various plants can pump nitrogen from the air into soils, and some researchers expected rising carbon dioxide to speed up this natural nitrogen pump, providing the nitrogen needed to store soil carbon. However, the research team found that this process, called nitrogen fixation, cannot keep up with increasing carbon dioxide unless other essential nutrients, such as potassium, phosphorus and molybdenum, are added as fertilizers.
Duh! And water too. There is always a limiting nutrient, usually water. This isn't news, it's gardening 101. No, wait, this is a prerequisite for gardening 101.
But, it's not that simple. Many previous studies have established that while there are limits that they change over time as ecologies adapt to increased CO2 levels.
One part of that is that as soil carbon increases less nutrients are needed for equivalent benefit beacuse soil chemistry is improved. More plants can grow with the exisitng nutrients.
Another factor is that soil organisms adapt as CO2 slowly increases to function in that new environment. To see this the experiments must be long term and mimic the slow rise. It's difficult since they don't have time to do it at a realistic pace, but they can get some idea of the process and do some guesswork.
Humans only account for about 5% of the carbon in the biosphere. It seems doubtful that this is enough to stress adaptive mechanisms. Still, there are always limits and probably not very many localities where CO2 is the limiting nutrient while all others are avaliable in abundance. There are some, but this isn't the general case.
This can be the case for arable land in production since nutrients are explicity added. Past practices were often insensitive to soil carbon - just tilling the soil causes the loss of huge amounts - so there is great potential for carbon sequestration in crop lands. Carbon lost in the past can be recaptured, and this will improve the soil too. It will grow more plants with less added nutrients.
Update:
More about the complexity of evaluating plant response to elevated CO2.
His research, which focused on the regrowth of the plant, reveals that alfalfa grows more with elevated concentrations of carbon dioxide (CO2), in particular when this condition coincides with high temperatures. The effects can be affected by other variables, such as the availability of water in the soil, which would reduce its growth and can modify its response to CO2. In addition, in the study it was confirmed that the process of photosynthesis can be stimulated or reduced by CO2, depending on the growth phase of the plant.
As this study highlighted, one of the most interesting aspects of this type of plant is the increase in nutrient storage in the roots, especially of proteins, when the plant is periodically cut back. These nutrient reserves contribute to rapid regrowth and to maintaining the perenniality of this crop. Similarly, it has been shown that a moderately dry climate maintained over time favors the accumulation of these reserve proteins, which can stimulate the growth of the plants during the following regrowth.
The results show the great variability of plant response to increases in CO2. Thus, a greater availability of CO2, which in principle should stimulate growth through increase photosynthesis, when it interacts with other variables such as the temperature or availability of water, can modify significantly the response of the alfalfa, depending on its stage of growth.
Add stage of growth to the variables that affect plant response to CO2 levels.
Wednesday, April 05, 2006
Since Bush gave the green light to bio-fuels in the SOTU it has become increasingly common to hear looney commentary and bizarre pitches from opportunistic politicians. In The Forest Killers Peter Huber imagines a future where such things are practiced rather than just talked about. [via A&L Daily]
Now the green-energy crowd is touting cellulosic ethanol. This is a blunder, one they will regret more than any of their previous blunders. It will level forests, destroy wetlands and disrupt ecosystems all around the globe.
Or at least it will if the enabling technology ever becomes economical. And it might. . .
History has already taught us what a carbohydrate energy economy does to a rich, green landscape--it levels it. The carbon balance goes sharply negative, too, when stove or cow is fueled with anything but waste or crops from existing farmland. It's pleasant to imagine that humanity might get all its liquid fuels from stable, legacy farms or from debris that would otherwise end up as fungus food. But that just isn't how humans have historically fed whatever they could feed with cellulose.
From the perspective of all things green, cellulose-splitting enzymes are much the same as fire or cow, only worse. Fire and cow consume cellulose, but the process is generally messy and inconvenient, which is a big advantage, from the plant's perspective. To improve on wood-burning fires, or grass-eating cows, perfect the cellulose-splitting enzyme. Then watch what 7 billion people will do to your forests and your grasslands.
Yet another benefit of omega-3 fats
NPD1 inhibits genes causing inflammation and cell death that oxidative stress and other triggers turn on. RPE cells contain the omega-3 fatty acid family member, DHA, which Dr. Bazan and colleagues found is a precursor to NPD1. RPE cells regulate the uptake, conservation, and delivery of DHA to the photoreceptor cells. DHA, known to be in short supply in patients with retinitis pigmentosa and Usher's syndrome, promotes protective cell signaling by facilitating the expression of helpful rather than destructive proteins as well as stimulating the production of NPD1. DHA and NPD1 also decrease the production of damaging free radicals. DHA has been shown by Dr. Bazan to promote survival and inhibit cell death not only of photoreceptor cells, but also of neurons in an experimental model of Alzheimer's disease.
Chance favors only the prepared mind.
the brain functions differently when a person arrives at "Aha!" solutions, compared to methodical solutions. The current study reveals that the distinct patterns of brain activity leading to "Aha!" moments of insight begin much earlier than the time a problem is solved. The research suggests that people can mentally prepare to have an "Aha!" solution even before a problem is presented. Specifically, as people prepare for problems that they solve with insight, their pattern of brain activity suggests that they are focusing attention inwardly, are ready to switch to new trains of thought, and perhaps are actively silencing irrelevant thoughts. These findings are important because they show that people can mentally prepare to solve problems with different thinking styles and that these different forms of preparation can be identified with specific patterns of brain activity. This study may eventually lead to an understanding of how to put people in the optimal "frame of mind" to deal with particular types of problems.
This research team's previous study revealed that just prior to an "Aha!" solution, after a person has been working on solving a problem, the brain momentarily reduces visual inputs, with an effect similar to a person shutting his or her eyes or looking away to facilitate the emergence into consciousness of the solution. The new study extends these findings by suggesting that mental preparation involving inward focus of attention promotes insight even prior to the presentation of a problem. Therefore, it may be that how a person is thinking before problem solving begins is just as important as the kind of thinking involved in reaching the solution, and perhaps even determines whether the solution will be derived with a sudden insight. . .
In two parallel experiments, participants solved these problems while brain activity was monitored either with electroencephalograms (EEG), which provide precise timing information and approximate anatomical information, or with functional magnetic resonance imaging (fMRI), which gives a more precise location of active brain areas, but with less precise timing. The researchers focused on neural activity that occurred during the period just before each problem was displayed.
The two brain imaging techniques yielded highly similar results and showed a different pattern of brain activity prior to problems that they subsequently solved with an "Aha!", compared to the pattern of brain activity prior to problems they solved more methodically. . .
Mental preparation that led to insight solutions was generally characterized by increased brain activity in temporal lobe areas associated with conceptual processing, and with frontal lobe areas associated with cognitive control or "top-down" processing. Jung-Beeman noted that "Problem solvers could use cognitive control to switch their train of thought when stuck on a problem, or possibly to suppress irrelevant thoughts, such as those related to the previous problem." In contrast, preparation that led to more methodical solutions involved increased neural activity in the visual cortex at the back of the brain -- suggesting that preparation for deliberate problem solving simply involved external focus of attention on the video monitor on which the problem would be displayed.
Tuesday, April 04, 2006
Orderly behavior may need random stimuli.
While working on their model – a network of interconnected pendulums, or "oscillators" – the researchers noticed that when driven by ordered forces the various pendulums behaved chaotically and swung out of sync like a group of intoxicated synchronized swimmers. This was unexpected – shouldn't synchronized forces yield synchronized pendulums?
But then came the real surprise: When they introduced disorder – forces were applied at random to each oscillator – the system became ordered and synchronized.
"The thing that is counterintuitive is that when you introduce disorder into the system – when the [forces on the pendulums] act at random – the chaos that was present before disappears and there is order," said Sebastian F. Brandt, physics graduate student and lead author of the study which appeared in the January 2006 edition of Physical Review Letters.
The physicists' research is not only hard to grasp for non-physicists, but puzzling for physicists, too. As supervisor Ralf Wessel, Ph.D., Washington University associate professor of physics in Arts & Sciences said, "Every physicist who hears this is surprised." . .
neurons can exhibit synchronous activity in response to a stimulus. To this point, she said, nobody has come up with an adequate explanation. And Wessel said, "Maybe the details of the neurons are completely irrelevant. Maybe it is only a property of oscillators."
A vital similarity between the model system and neurons is that they are both "nonlinear" – meaning that there is not a linear, or straight-ahead, correlation between the applied force and displacement. In other words, the oscillators in the model may be likened to a child on a swing. Within a mall range, the child will move in constant proportion to how hard you push them – if you push twice as hard, they will go twice as far. But nearly all complex systems in nature, like the physicists' model, are nonlinear. Once the child gets to a certain height, pushing twice as hard will not make the child go twice as far.
Neurons are composed of many elements and are typically nonlinear.
"When you hear your favorite music twice as loud you don't double the pleasure," mused Brandt, explaining how one aspect of the brain – hearing – is nonlinear.
While other research has shown that disorder can create order, these studies often involved manipulating parameters within the systems such as changing pendulum length. The researchers say that their work is novel because it involves changing externally applied forces. Thus, they believe, their findings might have potential in the real world, where it would be more difficult to change parameters within the system – neurons, for example – but relatively simple to apply an external forcing.
"This is of course basic research," said Brandt. "But what you can learn from this is that complex systems... sometimes behave in a very unexpected way, completely opposite to your intuition or expectation. … It will be interesting to see if the mechanism that we have found can actually be put to some use."
Monday, April 03, 2006
More evidence that it isn't high cholesterol that kills your heart, it's high levels of bad LDL cholesterol that gets you.
Having a high level of HDL cholesterol – the good cholesterol – is more important than having a low level of LDL – the bad cholesterol – in protecting individuals from heart attack, according to a study published in the March issue of American Heart Journal by researchers from the Indiana University School of Medicine and pharmaceutical company GlaxoSmithKline, Inc.
The researchers looked at the history of heart disease, age, sex, race, weight and other heart disease risk factors in almost 7,000 patients. The patients were predominately inner city residents and included a large number of African Americans, women, smokers and overweight people. The researchers found the strongest predictor of future heart attack was previous heart disease; age was the second strongest predictor and the third strongest predictor was HDL level.
"Most of the drugs that lower LDL also tend to raise HDL so until our study, when a person's health improved, you couldn't tell if that was due to lowering of the LDL or raising the HDL level," says study senior author William Tierney, M.D., IU Chancellor's Professor of Medicine and a Regenstrief Institute, Inc. research scientist. "We now know that more good cholesterol is more important than less bad cholesterol.
This has been claimed for a long time but some folks are slow I guess. The ealier post Eat Wild discussed the use of HDL as a medication. This has long been a claim of pastured beef and dairy products as well. Such products have less total fat than grain fed animals but more importantly it has higher levels of HDL cholesterol - less fat total but more good fat.
Sunday, April 02, 2006
Expecting fun is almost as good as having fun.
In a paper being presented in an American Physiological Society session at Experimental Biology 2006, Lee S. Berk of Loma Linda University, reports that . . . just the anticipation of the "mirthful laughter" involved in watching your favorite funny movie has some very surprising and significant neuroendocrine/hormone effects.
According to Berk: "The blood drawn from experimental subjects just before they watched the video had 27% more beta-endorphins and 87% more human growth hormone, compared to blood from the control group, which didn't anticipate the watching of a humorous video. . .
"Mirthful laughter diminishes the secretion of cortisol and epinephrine, while enhancing immune reactivity. In addition, mirthful laughter boosts secretion of growth hormone, an enhancer of these same key immune responses. The physiological effects of a single one-hour session viewing a humorous video has appeared to last up to 12 to 24 hours in some individuals," Berk noted, " while other studies of daily 30-minute exposure produces profound and long-lasting changes in these measures.
Though video watching doesn't appeal to everyone the effect may be more general. Anticipating having a fun time of any sort is likely good for you.
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