The Fresh Face of King Tut: Famous Pharaoh's Features Reconstructed Using High-Resolution CT Scanner

The Fresh Face of King Tut: Famous Pharaoh's Features Reconstructed Using High-Resolution CT Scanner

Under the leadership of Zahi Hawass, secretary general of Egypt’s Supreme Council of Antiquities, National Geographic has used the CT data to show the world how Tut looked the day he died, some 3,300 years ago. The process involved forensic artists and physical anthropologists from two countries and created two independently made busts of Tut.
The French team’s work will appear on the cover of the June issue of National Geographic magazine and in the two-hour world premiere special “King Tut’s Final Secrets,” on the National Geographic Channel May 15. The second rendering will be seen on National Geographic’s Web site at http://www.nationalgeographic.com/.
How the new face of Tut came about:
1) Using the CT data from scanning done in January, a “rapid prototype model” of the skull was made and provided to French forensic anthropologist Jean-Noel Vignal, of the Centre Technique de la Gendarmerie Nationale. Vignal, who works daily with police officials to reconstruct deceased crime victims, determined from the skull that the person had been male, 18 to 20 years old, with Caucasoid features. “Caucasoid” describes a major group of peoples of Europe, North Africa, the Near East and India.
2) From the CT data, Vignal and his team determined basic measurements and features of Tut’s face. For example, the size of the narrow nasal opening, considered a Caucasoid trait, allowed them to fix the size range of Tut’s nose. Other data guided them on the position of the king’s mouth and his receding chin. Vignal also used the data to calculate the correct thickness of skin on Tut’s face.
3) Vignal’s skull “map” then went to one of the world’s leading anthropological sculptors, Elisabeth Daynes of Paris. Daynes’s job was to combine the science with art to create the most accurate, lifelike face of Tut ever. She used Vignal’s conclusions as well as archaeological information supplied by Hawass that included two wooden sculptures made of Tut during his youth. Daynes used tissue-depth information to lay clay over the plastic skull models and build toward a human image with flesh, filling in the king’s eyebrow thickness, precise shape of the nose and lips, as well as the approximate shape and size of Tut’s ears.
4) Finally, Daynes made a plaster mold of her clay sculpture and created a flesh-toned silicone cast. Attentive to the tiniest detail, she placed glass eyes and implanted a head of hair with surgical precision. Skin tone, which could have varied from very dark to very light, was based on an average shade of modern-day Egyptians. Eyelashes, eye makeup known as “kohl,” and even jewelry were added to adorn the king as he was in life.
5) To further validate the French specialists’ work, National Geographic decided to provide the CT data to a second team — but without telling them who they were recreating. Working “blind,” Susan Antón, associate professor of anthropology at New York University, in consultation with Bradley Adams of the chief Medical Examiner’s office, studied the CT data. She quickly described the mystery person as male, age 18 to 19 years, and of African ancestry with several Caucasian affinities, possibly of north African origin — all uncannily accurate. Using this information artist Michael Anderson of the Yale Peabody Museum then created his own likeness of the mystery figure and cast it in plaster.
To the relief and jubilation of Hawass and National Geographic, the second likeness closely resembled the first, validating the process. Still, despite the solid scientific information used, it is impossible to know for certain everything about how King Tut looked — the shape of the top of his nose, the shape of his ears, the color of his eyes and skin — as they are not determined by the shape and proportions of his skull.

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Changing the Face of History

Forensic Anthropologists Reconstruct First President's Real Looks

September 1, 2005 — Using 3D laser scans of sculptures and processing images with math-based computer software, forensic anthropologists are making life-size models of George Washington at ages 19, 45, and 57. An exhibit featuring the reconstructed images and models will open at George Washington’s Mount Vernon estate in October 2006.

MOUNT VERNON, Va.--If a picture tells a thousand words then the portrait of America's first president, George Washington, may be telling a lie. Scientists are giving our founding father a virtual face-lift and revealing some surprising new looks.
There's no mistaking the face on the dollar bill. Even 10-year-old Ella Nejadi knows what George Washington looks like. "I know that he had a wig of white curly hair," she says. Not flattering, but it's what history teaches. Now scientists say it may not be what he really looked like. To prove it, they're re-creating our founding father.
Jeffrey H. Schwartz, a forensic anthropologist at the University of Pittsburgh, in Pennsylvania, says, "I have to do as much reconstruction of what I think he was like, physically, at the older age so I could then apply general rules of aging, but reverse to make him younger."
Forensic anthropologists use lasers to scan sculptures, busts and dentures. Then, computer scientists feed the scans into a computer that breaks down the image into tiny points. Using mathematics, the points are connected to form an image.
The new images are helping change the perception of Washington as a stiff, stern president. Schwartz says, "He would have been tough because he was tromping through the woods, but he would not have been as bulked up as he would have been later in life." The final images of Washington will help re-construct life-size models. But the young, good-looking Washington is sure to make the biggest impact.
James C. Rees, executive director of the Historic Mount Vernon in Mount Vernon, Va., says, "If we can show him as the athletic, as the adventurous guy that he really was, I think he'll be very appealing to kids." The completed life-size models will show Washington at ages 19, 45 and 57. The full exhibit featuring reconstructed images and models is scheduled to open at George Washington's Mount Vernon Estate and Gardens in October 2006. An on-line version of the exhibit will also be available.
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BACKGROUND: Forensic anthropologists are putting together the pieces to determine what George Washington looked like as a young man, at age 45, and as president.
ABOUT FORENSIC ANTHROPOLOGY: Fans of C.S.I. are familiar with the practice of forensic anthropology: it is often used to identify human remains. A good forensic anthropologist can tell a lot about a body from the bones: gender, age, height, weight, even racial group. Ridges where muscle was attached to the bone can help determine a body's physique in life, or whether that person was right or left handed (there would be more muscle attachment on the bones on the dominant side.) But only part of the facial shape can be determined from the underlying bone structure; the shape of the eyes, tip of the nose and the lips are largely guesswork. So facial reconstruction usually generates a resemblance to an individual, but not an exact likeness.
RE-CREATING GEORGE: A bust of Washington, believed to be the best existing likeness, was scanned into a computer. The anthropologists them created computer models, gradually adding the aspects that would change Washington's appearance as he aged. The computer then modeled the images at ages 19, 45, and 57.
WHAT'S THE POINT: Based on the computer models, along with dozens of other artifacts -- including analysis of snippets of hair and clothing, and his dentures -- specialists at Washington's home in Mount Vernon will build life-sized models of our first president at those different points in his life. The models should go on display in 2006 as part of a new $85 million education center and museum at the site.
SAVING FACE: Washington began losing his teeth in his 20s, and went through several pairs of dentures. Historians believe he was portrayed with a closed mouth and tight lips because he was embarrassed by the state of his teeth. Because of the accompanying bone loss, the shape of Washington's face probably changed dramatically as he aged. By the time he reached his 50s, his face was crooked: his chin receded on the left and protruded on the right because of the tooth loss.

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Chemistry Of Cooking

A Biochemist Explains The Chemistry Of Cooking

January 1, 2009 — A biochemist and cook explains that cooking is all about chemistry and knowing some facts can help chefs understand why recipes go wrong. Because cooking is essentially a series of chemical reactions, it is helpful to know some basics. For example, plunging asparagus into boiling water causes the cells to pop and result in a brighter green. Longer cooking, however, causes the plant's cell walls to shrink and releases an acid. This turns the asparagus an unappetizing shade of grey.

You love to cook, but have you whipped up some disasters? Even the best recipes can sometimes go terribly wrong. A nationally recognized scientist and chef says knowing a little chemistry could help.
Long before she was a cook, Shirley Corriher was a biochemist. She says science is the key to understanding what goes right and wrong in the kitchen.
"Cooking is chemistry," said Corriher. "It's essentially chemical reactions."
This kind of chemistry happens when you put chopped red cabbage into a hot pan. Heat breaks down the red anthocyanine pigment, changing it from an acid to alkaline and causing the color change. Add some vinegar to increase the acidity, and the cabbage is red again. Baking soda will change it back to blue.
Cooking vegetables like asparagus causes a different kind of reaction when tiny air cells on the surface hit boiling water.
"If we plunge them into boiling water, we pop these cells, and they suddenly become much brighter green," Corriher said.
Longer cooking is not so good. It causes the plant's cell walls to shrink and release acid.
"So as it starts gushing out of the cells, and with acid in the water, it turns cooked green vegetables into [a] yucky army drab," Corriher said.
And that pretty fruit bowl on your counter? "Literally, overnight you can go from [a] nice green banana to an overripe banana," Corriher said.
The culprit here is ethylene gas. Given off by apples and even the bananas themselves, it can ruin your perfect fruit bowl -- but put an apple in a paper bag with an unripe avocado, and ethylene gas will work for you overnight.
"We use this as a quick way to ripen," Corriher said. Corriher says understanding a little chemistry can help any cook.
"You may still mess up, but you know why," she said. When it works, this kind of chemistry can be downright delicious.
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WHAT ARE ACIDS AND BASES? An acid is defined as a solution with more positive hydrogen ions than negative hydroxyl ions, which are made of one atom of oxygen and one of hydrogen. Acidity and basicity are measured on a scale called the pH scale. The value of freshly distilled water is seven, which indicates a neutral solution. A value of less than seven indicates an acid, and a value of more than seven indicates a base. Common acids include lemon juice and coffee, while common bases include ammonia and bleach.
WHY DOES FOOD SPOIL? Processing and improper storage practices can expose food items to heat or oxygen, which causes deterioration. In ancient times, salt was used to cure meats and fish to preserve them longer, while sugar was added to fruits to prevent spoilage. Certain herbs, spices and vinegar can also be used as preservatives, along with anti-oxidants, most notably Vitamins C and E. In processed foods, certain FDA-approved chemical additives also help extend shelf life.
This report has been produced thanks to a generous grant from the Camille and Henry Dreyfus Foundation, Inc.

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New Theory On Why Male, Female Lemurs Same Size: 'Passive' Mate Guarding Influenced Evolution Of Lemur Size

ScienceDaily (Aug. 1, 2009) — When it comes to investigating mysteries, Sherlock Holmes has nothing on Rice University biologist Amy Dunham. In a newly published paper, Dunham offers a new theory for one of primatology's long-standing mysteries: Why are male and female lemurs the same size?
In most primate species, males have evolved to be much larger than females. Size is an advantage for males that guard females to keep other males from mating with them, and evolutionary biologists have long wondered why lemurs evolved differently. Some theories have suggested that environment played a role or that lemur social development was altered due to the extinction of predatory birds.
"Scientifically, this is quite a big question that researchers have debated for over 20 years," said Dunham, assistant professor of ecology and evolutionary biology. "I actually started doing research on lemurs as an undergraduate, working in Ranomafana (National Park in Madgascar), and the question about size monomorphism has bugged me since then."
In a paper featured on the cover of this month's Journal of Evolutionary Biology, Dunham offers one of the first new theories on lemur monomorphism in more than a decade.
After an exhaustive review of the observational work done on lemurs, Dunham came to the conclusion that male lemurs do guard their mates, just like other primates. But unlike gorillas and other primates that fight for mating rights with females, male lemurs have evolved to passively guard their mates.
They do this by depositing a solid plug inside the female's reproductive tract just as they finish mating. The plug is deposited as a liquid protein but quickly hardens and stays in place for a day or two. Since many female lemurs are sexually responsive to males for only one day out of the entire year, the plug serves the purpose of preventing other males from mating with the female, while also freeing the male to mate with other females during the brief time they are available.
"If the female has a short receptivity period, as most lemurs do, then we hypothesize that this is likely to be an advantageous strategy," said Dunham, who co-authored the paper with Rice evolutionary biologist Volker Rudolf.
To test their hypothesis, Dunham and Rudolf examined 62 primate species and found that copulatory plugs were most likely to occur in species where female sexual receptivity was very brief and where males and females were the same size. This was true both for lemur species and for a few other species, like South American squirrel monkeys.
"Our idea needs further testing because it's new, but it's more parsimonious than some of the old theories, and we're very excited about looking into it further," Dunham said. "We've made some explicit predictions about the conditions where this strategy should be favored, so there are plenty of ways it can be tested."
Dunham said she hopes to travel to Madagascar within the next year to begin gathering data for a new project that will examine the impacts of climate change on lemur populations.
Lemurs evolved on the African island in isolation from other primates for 65 million years, and they are well-known for having odd traits not found in other primates. For example, some lemurs hibernate, storing fat in their tails, and all have toothcombs -- teeth that are perfectly shaped for grooming. Lemurs also differ from other primates in another key respect that has also stymied primatologists for years: The females are usually the dominant sex.
Dunham's investigations into the long-standing mystery of female dominance among lemurs led her to put forward another important theory last year. Published in the journal Animal Behavior, the theory suggests that female lemurs tend to dominate males because the females do all of the work in rearing the young and therefore have more will to fight and win.
"Game theory predicts that when the fighting abilities of two contestants are comparable, the outcome will depend upon the value that each contestant places on the resources they are fighting over," she said. "In this case, the females clearly have more at stake, but the only reason the females are in a position to compete for dominance is because they're roughly the same size and strength as the males."
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White Tea: Solution To Obesity Epidemic?

ScienceDaily (May 7, 2009) — Possible anti-obesity effects of white tea have been demonstrated in a series of experiments on human fat cells (adipocytes). Researchers have now shown that an extract of the herbal brew effectively inhibits the generation of new adipocytes and stimulates fat mobilization from mature fat cells.
Marc Winnefeld led a team of researchers from Beiersdorf AG, Germany, who studied the biological effects of an extract of white tea – the least processed version of the tea plant Camellia sinensis. He said, "In the industrialized countries, the rising incidence of obesity-associated disorders including cardiovascular diseases and diabetes constitutes a growing problem. We've shown that white tea may be an ideal natural source of slimming substances".
After treating lab-cultured human pre-adipocytes with the tea extract, the authors found that fat incorporation during the genesis of new adipocytes was reduced. According to Winnefeld, "The extract solution induced a decrease in the expression of genes associated with the growth of new fat cells, while also prompting existing adipocytes to break down the fat they contain".
White tea is made from the buds and first leaves of the plant used to make green tea and the black tea most commonly drunk in Western countries. It is less processed than the other teas and contains more of the ingredients thought to be active on human cells, such as methylxanthines (like caffeine) and epigallocatechin-3-gallate (EGCG) – which the authors believe to be responsible for many of the anti-adipogenic effects demonstrated in their study.
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Black Tea May Fight Diabetes

ScienceDaily (July 28, 2009) — Long known for its antioxidants, immune boosting and, most recently, antihypertensive properties, black tea could have another health benefit. Black tea may be used to control diabetes, according to a study in the Journal of Food Science, published by the Institute of Food Technologists.
Next to water, tea is the second most consumed beverage in the world. Researchers from the Tianjin Key Laboratory in China studied the polysaccharide levels of green, oolong and black teas and whether they could be used to treat diabetes. Polysaccharides, a type of carbohydrate that includes starch and cellulose, may benefit people with diabetes because they help retard absorption of glucose.
The researchers found that of the three teas, the polysaccharides in black tea had the most glucose-inhibiting properties. The black tea polysaccharides also showed the highest scavenging effect on free radicals, which are involved in the onset of diseases such as cancer and rheumatoid arthritis.
“Many efforts have been made to search for effective glucose inhibitors from natural materials,” says lead researcher Haixia Chen. “There is a potential for exploitation of black tea polysaccharide in managing diabetes.”
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Drinking Tea May Offer Health Benefits, But Evidence Still Limited

ScienceDaily (Apr. 6, 2008) — Tea drinkers who opt for black, oolong, green or white teas may find that these beverages offer health benefits. The April issue of Mayo Clinic Health Letter covers what is -- and isn’t -- known about the health effects of drinking tea.
Black, oolong, green or white teas have a common origin. Each is produced from the leaves of the Camellia sinensis bush. The leaves are loaded with flavonoids and other polyphenols that work as antioxidants, possibly lowering the risk of some diseases.
While numerous studies have found possible benefits, the actual benefits of drinking tea are not certain. Most research about tea’s benefits is based on population (epidemiological) studies. Findings are limited because factors other than tea consumption could influence the results. Here’s some of what’s known about tea’s potential benefits:
Cardiovascular
It’s still uncertain if drinking tea over long periods might positively affect cholesterol levels, blood pressure and atherosclerosis. There’s some early evidence that regularly drinking green tea may reduce heart attack risk or atherosclerosis. There’s conflicting evidence on black tea consumption and heart attack risk reduction.
Cancer
It’s still unknown whether regular black tea consumption influences cancer rates. Early lab tests with white tea indicate it may protect against colon cancer in particular. So far, well-designed studies haven’t proven this.
Bone and joint health
Early laboratory research indicates green tea could be beneficial in reducing inflammation related to arthritis and slowing cartilage breakdown. Some early data indicate that regular tea consumption might improve bone mineral density in older women.
Memory
Studies are limited, but a recent one found that older adults in Japan who drank green tea daily showed less risk of memory difficulty, compared with those who didn’t drink tea regularly.
While there’s still much to learn about tea’s health benefits, the potential benefits seem to be in the cup, not in supplements or tea extract capsules. So far, there’s no certainty that the compounds in supplements are the same ones in tea, and even less certainty that these supplements might provide the same potential health benefits as tea.
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Benefits Of Green Tea In Reducing An Important Risk Factor For Heart Disease

ScienceDaily (July 3, 2008) — More evidence for the beneficial effect of green tea on risk factors for heart disease has emerged in a new study. The study found that the consumption of green tea rapidly improves the function of (endothelial) cells lining the circulatory system; endothelial dysfunction is a key event in the progression of atherosclerosis.
The study, performed by Dr Nikolaos Alexopoulos and colleagues at the 1st Cardiology Department, Athens Medical School in Greece, was a randomised trial involving the diameter measurement (dilatation) of the brachial artery of healthy volunteers on three separate occasions - after taking green tea, caffeine, and hot water (for a placebo effect). The measurements were taken at 30, 90 and 120 minutes after consumption. Dilatation of the brachial artery as a result of increased blood flow (following a brief period of ischaemia of the upper limb) is related to endothelial function and is known to be an independent predictor of cardiovascular risk.1
Results showed that endothelium-dependent brachial artery dilatation increased significantly after drinking green tea, with a peak increase of 3.9 per cent 30 minutes after consumption. The effect of caffeine consumption (or hot water) was not significant.
While black tea has been associated with improved short and long-term endothelial performance, this is the first time that green tea has been shown to have a short-term beneficial effect on the large arteries. Another study has already shown that green tea reverses endothelial dysfunction in smokers.
Green tea, which originates in China but is now consumed throughout the world, is made with pure leaves, and has undergone little oxidisation during processing. The cardiovascular benefits of all teas - as well as dark chocolate and red wine - are attributed to the flavonoids they contain and their antioxidant activity.2 However, says investigator Dr Charalambos Vlachopoulos, flavonoids in green tea are probably more potent antioxidants than in black tea because there has been no oxidisation.
"These findings have important clinical implications," says Dr Vlachopoulos. "Tea consumption has been associated with reduced cardiovascular morbidity and mortality in several studies. Green tea is consumed less in the Western world than black tea, but it could be more beneficial because of the way it seems to improve endothelial function. In this same context, recent studies have also shown potent anticarcinogenic effects of green tea, attributed to its antioxidant properties."
Notes
The study measured flow-mediated dilatation of the brachial artery, which is predominantly dependent on the release of nitric oxide from the endothelium and represents a well accepted estimate of endothelial function. Measurement of the brachial arteries was performed by high-resolution ultrasound.
Flavonoids are naturally found in many plants and have been shown to have many different biological effects in humans. Their antioxidant effects have been found in red wine, red grapes and dark chocolate. Oxidative stress, which has been associated with many human diseases, can be reversed by antioxidant intake.
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Chocolate, Wine And Tea Improve Brain Performance

ScienceDaily (Dec. 24, 2008) — All that chocolate might actually help finish the bumper Christmas crossword over the seasonal period. According to Oxford researchers working with colleagues in Norway, chocolate, wine and tea enhance cognitive performance.
The team from Oxford’s Department of Physiology, Anatomy and Genetics and Norway examined the relation between cognitive performance and the intake of three common foodstuffs that contain flavonoids (chocolate, wine, and tea) in 2,031 older people (aged between 70 and 74).
Participants filled in information about their habitual food intake and underwent a battery of cognitive tests.Those who consumed chocolate, wine, or tea had significantly better mean test scores and lower prevalence of poor cognitive performance than those who did not. The team reported their findings in the Journal of Nutrition.
The role of micronutrients in age-related cognitive decline is being increasingly studied. Fruits and beverages such as tea, red wine, cocoa, and coffee are major dietary sources of polyphenols, micronutrients found in plant-derived foods. The largest subclass of dietary polyphenols is flavonoids, and it has been reported in the past that those who consume lots of flavonoids have a lower incidence of dementia.
The latest findings seem to support the theory, although the researchers caution that more research would be needed to prove that it was flavonoids, rather than some other aspect of the foods studied, that made the difference.The effect was most pronounced for wine.
However, say the researchers, those overdoing it at Christmas should note that while moderate alcohol consumption is associated with better cognitive function and reduced risk of Alzheimer’s disease and dementia, heavy alcohol intake could be one of many causes of dementia – as well as a host of other health problems.
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Chemicals Found In Fruit And Vegetables Offer Dementia Hope

ScienceDaily (July 19, 2009) — A group of chemicals found in many fruits and vegetables, as well as tea, cocoa and red wine, could protect the brain from Alzheimer’s disease, a dementia expert will tell scientists at a conference July 11.
Speaking at the British Pharmacological Society’s Summer Meeting in Edinburgh, Dr Robert Williams will argue that, while much more research needs to be done, there is mounting evidence that certain flavonoids – chemicals found in plants and food derived from plants – might provide therapeutic benefit for Alzheimer’s sufferers.
“There have been some intriguing epidemiological studies that the consumption of flavonoid-rich vegetables, fruit juices and red wine delays the onset of the disease,” says Dr Williams, a Biochemist working at Kings College London. “These reports, while not as powerful as controlled, randomised clinical trials, have encouraged a number of research groups, including our own, to investigate the biology of flavonoids in more detail.”
Dr Williams says that a lack of good research and clinical trial data meant this field of research had suffered from a lack of scientific credibility, not helped by early positive health claims for flavonoids that cannot access the brain or are broken down too rapidly by the body to be of any benefit. Scepticism also persists because flavonoids are known antioxidants and yet clinical trials with other antioxidants, such as vitamin E, showed no reported benefit on either symptoms or disease progression in dementia.
However, a new concept is emerging that suggests flavonoids do not act simply as antioxidants but exert their biological effects through other mechanisms. A small number of recent studies carried out in models of Alzheimer’s disease have found that oral administration of green tea flavonoids or grape flavonoids reduces brain pathology and, in some cases, improves cognition. Dr Williams and colleagues have focused their own cellular studies on a flavonoid called epicatechin, which is abundant in a number of foodstuffs, including cocoa.
“We have found that epicatechin protects brain cells from damage but through a mechanism unrelated to its antioxidant activity and shown in laboratory tests that it can also reduce some aspects of Alzheimer’s disease pathology.
“This is interesting because epicatechin and its breakdown products are measurable in the bloodstream of humans for a number of hours after ingestion and it is one of the relatively few flavonoids known to access the brain suggesting it has the potential to be bioactive in humans.”
Alzheimer’s disease is a devastating, progressive disorder affecting an estimated 15-20 million people worldwide. Over the past four decades, through worldwide research efforts, it is now known that in the brains of people with Alzheimer’s disease there are abnormal cellular processes which lead to neurodegeneration and dementia. Understanding these disease processes at the molecular level will allow the development of pharmacological agents to block these processes, and lead the way for effective therapies in Alzheimer’s disease.
Central to the development of Alzheimer’s disease is toxic beta-amyloid peptide, a substance that is normally produced in the brain but, in this disease, is deposited abnormally as amyloid plaques. Dr Williams has shown that flavonoids can protect brain cells against the toxic actions of beta-amyloid.
He adds: “Although our findings support the general concept that dietary intake of flavonoid-rich foods or supplements could impact on the development and progression of dementia, they are clearly insufficient to make any sort of nutritional recommendations at this stage.
“The challenge now is to identify the single flavonoid or combination of flavonoids that exert the most positive effects and to define the mechanisms of action and optimal quantity required before embarking on clinical trials to treat their effectiveness in dementia.”
The British Pharmacological Society Summer Meeting in Edinburgh will also highlight the work of three other scientists who are working on different aspects of Alzheimer’s disease. They will present their latest research findings showing that insight into disease mechanisms is leading to the development of agents with the potential to become new and effective therapies for Alzheimer’s disease.
Dr Tiziana Borsello, from the Mario Negri Institute of Pharmacological Research in Milan, Italy, will present data which show that cell death in Alzheimer’s disease and other neurodegenerative states involves the activation of a protein called JNK. Over a number of years, she and her team have developed the powerful and specific cell-permeable inhibitor of JNK (D-JNKI1). In her talk, Dr Borsello will show that D-JNKI1 can reduce production of beta-amyloid and amyloid plaques and improve memory in mice. This exciting research opens up new prospects for the treatment of Alzheimer’s disease.
Professor Michael Rowan, from University College Dublin, Ireland, will present data showing that beta-amyloid can directly affect the physiological processes involved in memory formation. His research has identified therapeutic agents that target the cytokine system in the brain and are able to prevent this detrimental effect of beta-amyloid. This line of enquiry suggests that agents that remove cytokines could improve cognitive function in Alzheimer’s disease.
Dr Warren Hirst, from Wyeth Pharmaceuticals, Princeton, USA, will outline two potential therapeutic strategies. The first is the discovery and development of novel potent, selective and brain-penetrant small molecule beta-secretase inhibitors. These investigational small molecules have the potential to prevent the accumulation of beta-amyloid in the brain. The second strategy addresses the cognitive deficits associated with the disease, which are only partially addressed by current therapies. Neurotransmitter receptors in the brain play an important role in cognitive processes and new evidence suggests that blocking a specific class of receptors, the 5-HT1A receptors, can improve learning and memory in rats and mice. These, or similar molecules, may improve cognitive function in Alzheimer’s disease patients.
In summary, the symposium highlights how basic molecular and pharmacological research, including the work presented here, has enabled the identification and development of agents with promise to treat this devastating disease. Turning the findings from research into new medicines which are effective to treat Alzheimer’s disease is some way off, but is within reach.
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Eating High Levels Of Fructose Impairs Memory In Rats

ScienceDaily (Aug. 1, 2009) — Researchers at Georgia State University have found that diets high in fructose — a type of sugar found in most processed foods and beverages — impaired the spatial memory of adult rats.
Amy Ross, a graduate student in the lab of Marise Parent, associate professor at Georgia State's Neuroscience Institute and Department of Psychology, fed a group of Sprague-Dawley rats a diet where fructose represented 60 percent of calories ingested during the day.
She placed the rats in a pool of water to test their ability to learn to find a submerged platform, which allowed them to get out of the water. She then returned them to the pool two days later with no platform present to see if the rats could remember to swim to the platform's location.
"What we discovered is that the fructose diet doesn't affect their ability to learn," Parent said. "But they can't seem to remember as well where the platform was when you take it away. They swam more randomly than rats fed a control diet."
Fructose, unlike another sugar, glucose, is processed almost solely by the liver, and produces an excessive amount of triglycerides — fat which get into the bloodstream. Triglycerides can interfere with insulin signaling in the brain, which plays a major role in brain cell survival and plasticity, or the ability for the brain to change based on new experiences.
Results were similar in adolescent rats, but it is unclear whether the effects of high fructose consumption are permanent, she said.
Parent's lab works with Timothy Bartness, Regents' Professor of Biology, and John Mielke of the University of Waterloo in Waterloo, Ontario, Canada to examine how diet influences brain function.
Although humans do not eat fructose in levels as high as rats in the experiments, the consumption of foods sweetened with fructose — which includes both common table sugar, fruit juice concentrates, as well as the much-maligned high fructose corn syrup — has been increasing steadily. High intake of fructose is associated with numerous health problems, including insulin insensitivity, type II diabetes, obesity and cardiovascular disease.
"The bottom line is that we were meant to have an apple a day as our source of fructose," Parent said. "And now, we have fructose in almost everything." Moderation is key, as well as exercise, she said.
Exercise is a next step in ongoing research, and Parent's team will investigate whether exercise might mitigate the memory effects of high fructose intake. Her lab is also researching whether the intake of fish oil can prevent the increase of triglycerides and memory deficits. Results from that research will be presented by her graduate student Emily Bruggeman at the 2009 Society for Neuroscience meeting in Chicago this fall.
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Agriculture

The practice of agriculture is also known as "farming", while scientists, inventors and others devoted to improving farming methods and implements are also said to be engaged in agriculture. Subsistence farming, who farms a small area with limited resource inputs, and produces only enough food to meet the needs of his/her family.
At the other end is commercial intensive agriculture, including industrial agriculture.
Such farming involves large fields and/or numbers of animals, large resource inputs (pesticides, fertilizers, etc.), and a high level of mechanization.
These operations generally attempt to maximize financial income from grain, produce, or livestock. Modern agriculture extends well beyond the traditional production of food for humans and animal feeds.
Other agricultural production goods include timber, fertilizers, animal hides, leather, industrial chemicals (starch, sugar, alcohols and resins), fibers (cotton, wool, hemp, silk and flax), fuels (methane from biomass, ethanol, biodiesel), cut flowers, ornamental and nursery plants, tropical fish and birds for the pet trade, and both legal and illegal drugs (biopharmaceuticals, tobacco, marijuana, opium, cocaine). The 20th Century saw massive changes in agricultural practice, particularly in agricultural chemistry.
Agricultural chemistry includes the application of chemical fertilizer, chemical insecticides, and chemical fungicides, soil makeup, analysis of agricultural products, and nutritional needs of farm animals.
Beginning in the Western world, the green revolution spread many of these changes to farms throughout the world, with varying success. Other recent changes in agriculture include hydroponics, plant breeding, hybridization, gene manipulation, better management of soil nutrients, and improved weed control.
Genetic engineering has yielded crops which have capabilities beyond those of naturally occuring plants, such as higher yields and disease resistance.
Modified seeds germinate faster, and thus can be grown in an extended growing area.
Genetic engineering of plants has proven controversial, particularly in the case of herbicide-resistant plants. As of 2006, an estimated 36 percent of the world's workers are employed in agriculture (down from 42% in 1996), making it by far the most common occupation.
However, the relative significance of farming has dropped steadily since the beginning of industrialization, and in 2006 – for the first time in history – the services sector overtook agriculture as the economic sector employing the most people worldwide.
Also, agricultural production accounts for less than five percent of the gross world product (an aggregate of all gross domestic products)..
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Parasites May Have Had Role In Evolution Of Sex

ScienceDaily (July 31, 2009) — What's so great about sex? From an evolutionary perspective, the answer is not as obvious as one might think. An article published in the July issue of the American Naturalist suggests that sex may have evolved in part as a defense against parasites.
Despite its central role in biology, sex is a bit of an evolutionary mystery. Reproducing without sex—like microbes, some plants and even a few reptiles—would seem like a better way to go. Every individual in an asexual species has the ability to reproduce on its own. But in sexual species, two individuals have to combine in order to reproduce one offspring. That gives each generation of asexuals twice the reproductive capacity of sexuals. Why then is sex the dominant strategy when the do-it-yourself approach is so much more efficient?
One hypothesis is that parasites keep asexual organisms from getting too plentiful. When an asexual creature reproduces, it makes clones—exact genetic copies of itself. Since each clone has the same genes, each has the same genetic vulnerabilities to parasites. If a parasite emerges that can exploit those vulnerabilities, it can wipe out the whole population. On the other hand, sexual offspring are genetically unique, often with different parasite vulnerabilities. So a parasite that can destroy some can't necessarily destroy all. That, in theory, should help sexual populations maintain stability, while asexual populations face extinction at the hands of parasites.
The scenario works on mathematical models, but there have been few attempts to see if it holds in nature.
Enter Potamopyrgus antipodarum, a snail common in fresh water lakes in New Zealand. What makes these snails interesting is that there are sexual and asexual versions. They provide scientists with an opportunity to compare the two versions side-by-side in nature.
Jukka Jokela of the Swiss Federal Institute of Aquatic Science and Technology, Mark Dybdahl of the University of Washington and Curtis Lively of Indian University, Bloomington began observing several populations of these snails for ten years starting in 1994. They monitored the number of sexuals, the number asexuals, and the rates of parasite infection for both.
The team found that clones that were plentiful at the beginning of the study became more susceptible to parasites over time. As parasite infections increased, the once plentiful clones dwindled dramatically in number. Some clonal types disappeared entirely. Meanwhile, sexual snail populations remained much more stable over time. This, the authors say, is exactly the pattern predicted by the parasite hypothesis.
"The rise and fall of these female-only lineages was surprisingly fast and consistent with the prediction of the parasite hypothesis for sex," Jokela said. "These results suggest that sexual reproduction provides an evolutionary advantage in parasite rich environments."
So we may well have to thank parasites—in spite of their nasty reputation—for the joy of sex.
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Science News

Hot Laptops: Engineers Aim To Solve 'Burning' Computer Problem

ScienceDaily (Oct. 1, 2008) — If you've balanced a laptop computer on your lap lately, you probably noticed a burning sensation. That's because ever-increasing processing speeds are creating more and more heat, which has to go somewhere — in this case, into your lap.

Two researchers at the University of Virginia's School of Engineering and Applied Science aim to lay the scientific groundwork that will solve the problem using nanoelectronics, considered the essential science for powering the next generation of computers.
"Laptops are very hot now, so hot that they are not 'lap' tops anymore," said Avik Ghosh, an assistant professor in the Charles L. Brown Department of Electrical and Computer Engineering. “The prediction is that if we continue at our current pace of miniaturization, these devices will be as hot as the sun in 10 to 20 years."
To head off this problem, Ghosh and Mircea Stan, also a professor in the department, are re-examining nothing less than the Second Law of Thermodynamics. The law states that, left to itself, heat will transfer from a hotter unit to a cooler one — in this case between electrical computer components — until both have roughly the same temperature, a state called "thermal equilibrium."
The possibility of breaking the law will require Ghosh and Stan to solve a scientifically controversial — and theoretical — conundrum known as "Maxwell's Demon."
Introduced by Scottish physicist James Clerk Maxwell in 1871, the concept theorizes that the energy flow from hot to cold could be disrupted if there were a way to control the transfer of energy between two units. Maxwell's Demon would allow one component to take the heat while the other worked at a lower temperature.
This could be accomplished only if the degree of natural disorder, or entropy, were reduced. And that's the "demon" in Maxwell's Demon. "Device engineering is typically based on operating near thermal equilibrium," Ghosh said.
But, he added, nature has examples of biological cells that operate outside thermal equilibrium.
"Chlorophyll, for example, can convert photons into energy in highly efficient ways that seem to violate traditional thermodynamic expectations," he said.
A closely related concept, Brownian "ratchets," will also be explored. This concept proposes that devices could be engineered to convert non-equilibrium electrical activity into directed motion, allowing energy to be harvested from a heat source.
If computers could be made with components that operate outside thermal equilibrium, it could mean better computer performance. Basically, your laptop wouldn't burst into flames as it processes larger amounts of information at faster speeds. Also, because it would operate at extremely low power levels and would have the ability to harness, or scavenge, power dissipated by other functions, battery life would increase.
Combining Ghosh's command of physics with Stan's expertise in electrical engineering, the two hope to bridge the concept of tackling Maxwell's Demon and Brownian ratchets from theoretical physics to engineered technologies.
"These theories have been looked at from a physics perspective for years, but not from the perspective of electrical engineering," Stan said. "So that's where we are trying to break some ground."

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Breakdown In Planck's Law: Bringing Objects Close Together Can Boost Radiation Heat Transfer

ScienceDaily (July 31, 2009) — A well-established physical law describes the transfer of heat between two objects, but some physicists have long predicted that the law should break down when the objects are very close together. Scientists had never been able to confirm, or measure, this breakdown in practice. For the first time, however, MIT researchers have achieved this feat, and determined that the heat transfer can be 1,000 times greater than the law predicts.

The new findings could lead to significant new applications, including better design of the recording heads of the hard disks used for computer data storage, and new kinds of devices for harvesting energy from heat that would otherwise be wasted.
Planck's blackbody radiation law, formulated in 1900 by German physicist Max Planck, describes how energy is dissipated, in the form of different wavelengths of radiation, from an idealized non-reflective black object, called a blackbody. The law says that the relative thermal emission of radiation at different wavelengths follows a precise pattern that varies according to the temperature of the object. The emission from a blackbody is usually considered as the maximum that an object can radiate.
The law works reliably in most cases, but Planck himself had suggested that when objects are very close together, the predictions of his law would break down. But actually controlling objects to maintain the tiny separations required to demonstrate this phenomenon has proved incredibly difficult.
"Planck was very careful, saying his theory was only valid for large systems," explains Gang Chen, MIT's Carl Richard Soderberg Professor of Power Engineering and director of the Pappalardo Micro and Nano Engineering Laboratories. "So he kind of anticipated this [breakdown], but most people don't know this."
Part of the problem in measuring the way energy is radiated when objects are very close is the mechanical difficulty of maintaining two objects in very close proximity, without letting them actually touch. Chen and his team, graduate student Sheng Shen and Columbia University Professor Arvind Narayaswamy, solved this problem in two ways, as described in a paper to be published in the August issue of the journal Nano Letters (available now online). First, instead of using two flat surfaces and trying to maintain a tiny gap between them, they used a flat surface next to a small round glass bead, whose position is easier to control. "If we use two parallel surfaces, it is very hard to push to nanometer scale without some parts touching each other," Chen explains, but by using a bead there is just a single point of near-contact, which is much easier to maintain. Then, they used the technology of the bi-metallic cantilever from an atomic-force microscope to measure the temperature changes with great precision.
"We tried for many years doing it with parallel plates," Chen says. But with that method, they were unable to sustain separations of closer than about a micron (one millionth of a meter). By using the glass (silica) beads, they were able to get separations as small as 10 nanometers (10 billionths of a meter, or one-hundredth the distance achieved before), and are now working on getting even closer spacings.
Professor Sir John Pendry of Imperial College London, who has done extensive work in this field, calls the results "very exciting," noting that theorists have long predicted such a breakdown in the formula and the activation of a more powerful mechanism.
"Experimental confirmation has proved elusive because of the extreme difficulty in measuring temperature differences over very small distances," Pendry says. "Gang Chen's experiments provide a beautiful solution to this difficulty and confirm the dominant contribution of near field effects to heat transfer."
In today's magnetic data recording systems - such as the hard disks used in computers - the spacing between the recording head and the disk surface is typically in the 5 to 6 nanometer range, Chen says. The head tends to heat up, and researchers have been looking for ways to manage the heat or even exploit the heating to control the gap. "It's a very important issue for magnetic storage," he says. Such applications could be developed quite rapidly, he says, and some companies have already shown a strong interest in this work
The new findings could also help in the development of new photovoltaic energy conversion devices to harness photons emitted by a heat source, called thermophovoltaic, Chen says. "The high photon flux can potentially enable higher efficiency and energy density thermophovoltaic energy converters, and new energy conversion devices," he says.
The new findings could have "a broad impact," says Shen. People working with devices using small separations will now have a clear understanding that Planck's law "is not a fundamental limitation," as many people now think, he says. But further work is needed to explore even closer spacings, Chen says, because "we don't know exactly what the limit is yet" in terms of how much heat can be dissipated in closely spaced systems. "Current theory will not be valid once we push down to 1 nanometer spacing."
And in addition to practical applications, he says, such experiments "might provide a useful tool to understand some basic physics."
The work was funded by the U.S. Department of Energy and the Air Force Office of Scientific Research.

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Guiding Light Around Corners With New Metamaterial Device

ScienceDaily (Aug. 1, 2009) — Using a composite metamaterial to deliver a complex set of instructions to a beam of light, Boston College physicists have created a device to guide electromagnetic waves around objects such as the corner of a building or the profile of the eastern seaboard.
As directed by the researchers' novel device, these beams continue to behave as if traveling in a straight line. In one computer simulation, Assistant Professor of Physics Willie J. Padilla and researcher Nathan Landy revealed the device could steer a beam of light along the boundary of the US, stretching from Michigan to Maine, down the seaboard, around Florida and into the Louisiana bayou, according to research published in the research journal Optics Express.
The researchers accomplished their feat by developing a much more precise set of instructions, which create a grid-like roadmap capable of twisting and turning a beam of light around objects or space. Their discovery is an extension of earlier metamaterial "cloaking" techniques, which have conjured up images of the Harry Potter character disappearing beneath his invisibility cloak.
Padilla and Landy report developing a space-mapping technique that delivers greater precision and efficiency guiding light along pathways that previously were too complex to sustain – from 90-degree angles to the rugged coastal profile of Maine. Furthermore, they've built this new device using relatively common dielectric materials, such as silicon.
"Our method combines the novel effects of transformational optics with the practicality of dielectric construction," Padilla and Landy report. "We show that our structures are capable of guiding light in an almost arbitrary fashion over an unprecedented range of frequencies."
The discovery builds upon a decade-long revolution in electromagnetics brought about by the emergence of metamaterials. Constructed from artificial composites, metamaterials have exhibited effects such as directing light at a negative index of refraction.
Researchers have combined metamaterials with artificial optical devices – also known as transformational optics – to demonstrate the "invisibility cloak" effect, essentially directing light around a space and effectively masking its existence. In addition, other researchers have used a method known as quasi-conformal mapping and very complex metamaterials to issue a somewhat imprecise set of instructions that create another space-cloaking effect.
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Engineering Students Rock

January 1, 2009 — Mechanical engineers combined their skills with that of electrical engineering and computer science to create a college class inspired by the Guitar Hero game. The hands-on course requires students to build their own guitar. To do this, students choose a shape for the guitar, which is cut out of lumber by a computer. Located under the guitar strings, magnets detect vibrations and wire coils send an electronic signal to an amplifier and speaker. Effects pedals can also distort the sound and add special effects.

Skills from mechanical engineering, electrical engineering and computer science come together to form a cool kind of class that's a hit with students.
The video game Guitar Hero is a chart-busting hit. It was the inspiration that mechanical engineering graduate student and teacher Gavin Garner needed for a class assignment.
"I realized the students enjoyed pretending they were actual guitar players, and I thought, 'Why not have them actually build the real thing in the lab?'" said Garner, of the University of Virginia in Charlottesville, Va.
Garner's class isn't a music class. It's a new hands-on course combining skills from mechanical, electrical and software engineering called mechatronics. Mechanical engineering student Brad Nichols' guitar rocks.
"I was thrilled with the guitar," Nichols said. "I thought it looked great for something that was made with two by fours by students in a lab in two or three weeks. It actually sounds pretty good."
Students pick the shape and a computer automatically cuts the guitar from lumber. Basic magnets, nails and wire coils are mounted under the strings. The magnets pick up the vibrations of the strings and the wire coils send an electronic signal to an amplifier and speaker to produce sound.
"Then, the electrical signal travels down through into these effects pedals which distort the sound and add special effects, which changes the tone of the music," Garner said.
The designs show the creativity that went into the guitars, and the sound shows the science skills that created fun, useable objects that students love. "When I want to appreciate what I learned in school, I'll plug that in and strum around on it a little bit," Nichols said.
Another class assignment had students design a Mech-E-Mouse, a robot programmed to navigate through mazes to find a piece of electronic cheese.
show background -->
WHAT IS PITCH: Sound waves are pressure waves. A vibrating object creates a disturbance in the surrounding air, much like a stone cast in a quiet pond will cause waves to ripple outward from the spot where the stone hit. All sound waves have wavelength and frequency. Objects that vibrate very quickly create short wavelengths and a high-pitched sound. Objects that vibrate very slowly create long wavelengths and a low-pitched sound. Frequency measures the speed of vibration in a unit called a Hertz (Hz), and 1 Hz is equivalent to 1 vibration per second. Pluck a string on a guitar, and it might vibrate 500 times per second, so the sound wave's frequency would be 500 Hertz. Pitch simply denotes those frequencies within the range of human hearing (from about 20 Hz to 20,000 Hz). The faster the rate of vibration, the higher the pitch; the slower the rate of vibration, the lower the pitch.
WHAT MAKES ELECTRIC GUITARS LOUD? Essentially this is possible because of two items: an amplifier and a pick-up. Amplifiers, as you may expect, increase the amplitude or volume of sound and other signals. For audio amplifiers that means a sound must be turned into an electric signal, and sent into the amplifier before it emerges many times louder than the level at which it was originally produced. It is essentially a speaker whose source can be a guitar, a CD, a microphone, or many other items. A pick-up transforms the movement of guitar strings into an electrical signal that can be transmitted to amplifiers or recording equipment. Some use magnets wrapped inside a coil of wire, while others use alternate methods, such as piezoelectric crystals (which respond to physical stress or deformity by creating electrical energy).
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NOAA Bans Commercial Harvesting Of Krill

ScienceDaily (July 30, 2009) — The National Oceanic and Atmospheric Administration (NOAA) has published a final rule in the Federal Register prohibiting the harvesting of krill in the Exclusive Economic Zone (EEZ) off the coasts of California, Oregon, and Washington. The rule goes into effect on August 12, 2009. Krill are a small shrimp-like crustacean and a key source of nutrition in the marine food web.
"Krill are the foundation for a healthy marine ecosystem," said Mark Helvey, NOAA's Fisheries Service Southwest Assistant Regional Administrator for Sustainable Fisheries. "Protecting this vital food resource will help protect and maintain marine resources and put federal regulations in line with West-Coast states."
While the States of California, Oregon and Washington currently have regulations prohibiting the harvesting of krill within three miles of their coastlines, there was no similar federal restriction within the three to 200-mile confines of the EEZ.
The krill prohibition was adopted as Amendment 12 to the Coastal Pelagic Species Fishery Management Plan (FMP), which was developed by the Pacific Fishery Management Council (PFMC) under the Magnuson-Stevens Fishery Conservation and Management Act. The krill harvest prohibition was originally proposed to the PFMC and NOAA Fisheries Service by NOAA's Office of National Marine Sanctuaries. Today's rule implements Amendment 12 to the FMP and is intended to preserve key nutritional relationships in the California Current ecosystem, which includes five National Marine Sanctuaries.
"This is a great success for protecting the entire California Current ecosystem", said William Douros, West Coast Regional Director for NOAA's Office of National Marine Sanctuaries. "This decision reflects strong teamwork within NOAA and a commitment to addressing the issues raised by the Pacific Fishery Management Council and Sanctuary Advisory Councils."
Amendment 12 adds all species of krill under a new category, "prohibited harvest species." This new group may not be caught or taken by any fishery or gear type within the EEZ.
Krill are important because they convert microscopic phytoplankton into a food source for numerous other species and are a principal food source for many species of fish, seabirds and marine mammals. Some of the species that depend on krill as prey are listed as threatened or endangered under the Endangered Species Act, and many others are important as target species for commercial and recreational fisheries on the west coast.
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Warmer Environment Means Shorter Lives For Cold-blooded Animals

ScienceDaily (July 31, 2009) — Temperature explains much of why cold-blooded organisms such as fish, amphibians, crustaceans, and lizards live longer at higher latitudes than at lower latitudes, according to research recently published in the Proceedings of the National Academy of Sciences (PNAS) online. Assistant Professor Dr. Stephan Munch and Ph.D. candidate Santiago Salinas, both of Stony Brook University's School of Marine and Atmospheric Sciences (SoMAS), found that for a diverse range of species whose body temperatures vary with the temperature of their surroundings, ambient temperature is the dominant factor controlling geographic variation of lifespan within species.
We were intrigued by the fact that that pearl mussels in Spain have a maximum lifespan of 29 years, while in Russia, individuals of the same species live nearly 200 years," said Dr. Munch. "We wondered how a relatively small difference in latitude (Spain 43ºN and Russia 66ºN) could have such a drastic impact on lifespan. While one might expect that local adaptations or geographic variations in predator and food abundance would account for this disparity, we wanted to see whether the geographical variation in lifespan that we see in all sorts of species has a common physiological basis in temperature."
Munch and Salinas looked at lifespan data from laboratory and field observations for over 90 species from terrestrial, freshwater, and marine environments. They studied organisms with different average longevities--from the copepod Arcartia tonsa, which has an average lifespan of 11.6 days, to the pearl mussel Margaritifera margaritifera, which has an average lifespan of 74 years. They found that across this wide range of species, temperature was consistently exponentially related to lifespan.
The relationship between temperature and lifespan that Munch and Salinas found through data analysis was strikingly similar to the relationship that the metabolic theory of ecology (MTE) predicts. The MTE is a modeling framework that has been used to explain the way in which life history, population dynamics, geographic patterns, and other ecological processes scale with an animal's body size and temperature.
"You can think of an animal as a beaker in which chemical reactions are taking place," said Salinas. "The same rules that apply to a liquid inside a beaker should apply to animals. Chemists have a relationship for how an increase in temperature will speed up reaction rates, so the MTE borrows that relationship and applies it--with some obvious caveats--to living things."
The lifespan in 87% of the free-living species Munch and Salinas studied varied as predicted by the MTE. Yet after removing the effect of temperature, there was still considerable variation in lifespan within species, indicating that other, local factors still play a role in determining lifespan.
"It is interesting to consider how cold-blooded species are likely to react in the face of global warming," said Salinas. "Because of the exponential relationship between temperature and lifespan, small changes in temperature could result in relatively large changes in lifespan. We could see changes to ecosystem structure and stability if cold-blooded species change their life histories to accommodate warmer temperatures but warm-blooded species do not."
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Scientists Expect Wildfires To Increase As Climate Warms In Coming Decades

ScienceDaily (July 29, 2009) — As the climate warms in the coming decades, atmospheric scientists at Harvard's School of Engineering and Applied Sciences (SEAS) and their colleagues expect that the frequency of wildfires will increase in many regions. The spike in the number of fires could also adversely affect air quality due to the greater presence of smoke.
The study, led by SEAS Senior Research Fellow Jennifer Logan, was published in the June 18th issue of Journal of Geophysical Research. In their pioneering work, Logan and her collaborators investigated the consequences of climate change on future forest fires and on air quality in the western United States. Previous studies have probed the links between climate change and fire severity in the West and elsewhere. The Harvard study represents the first attempt to quantify the impact of future wildfires on the air we breathe.
"Warmer temperatures can dry out underbrush, leading to a more serious conflagration once a fire is started by lightening or human activity," says Logan. "Because smoke and other particles from fires adversely affect air quality, an increase in wildfires could have large impacts on human health."
Using a series of models, the scientists predict that the geographic area typically burned by wildfires in the western United States could increase by about 50% by the 2050s due mainly to rising temperatures. The greatest increases in area burned (75-175%) would occur in the forests of the Pacific Northwest and the Rocky Mountains. In addition, because of extra burning throughout the western U.S., one important type of smoke particle, organic carbon aerosols, would increase, on average, by about 40 percent during the roughly half-century period.
To conduct the research, the team first examined a 25-year record of observed meteorology and fire statistics to identify those meteorological factors that could best predict area burned for each ecosystem in the western United States. To see how these meteorological factors would change in the future, they then next ran a global climate model out to 2055, following the A1B scenario in greenhouse gas emissions. This scenario, one of several devised by the Intergovernmental Panel on Climate Change, describes a future world with rapid economic growth and balanced energy generation from fossil and alternative fuels. Relative to the other scenarios, it leads to a moderate warming of the earth's average surface temperature, about 3oF (1.6 oC) by 2050.
"By hypothesizing that the same relationships between meteorology and area burned still hold in the future, we then could predict wildfire activity and emissions from 2000 to the 2050's," explains Logan.
As a last step, the researchers used an atmospheric chemistry model to understand how the change in wildfire activity would affect air quality. This model, combining their predictions of areas burned with 2050's meteorology data, shows the emissions and fate of the smoke and other particles emitted by the future wildfires. The resulting diminished air quality could lead to smoggier skies and adversely affect those suffering from lung and heart conditions such as asthma and chronic bronchitis.
The authors expect the work will help policymakers gauge the "climate penalty" related to ongoing efforts to reduce air pollution across the United States. In addition, the study underscores the need for a vigorous fire management plan.
The team next plans to focus on future wildfires and air quality over the densely populated areas in California and in the southwest United States.
Logan's collaborators included SEAS Research Associate Loretta Mickley and former postdocs Dominick Spracklen (now at University of Leeds), Rynda Hudman, and Rosemarie Yevich; Michael D. Flannigan, Canadian Forest Service; and Anthony. L. Westerling, University of California, Merced. The authors acknowledge the support of a STAR (Science to Achieve Results) grant from National Center for Environmental Research of the U.S. Environmental Protection Agency and a grant from the National Aeronautics and Space Administration
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Mines Could Provide Geothermal Energy

ScienceDaily (July 31, 2009) — Mine shafts on the point of being closed down could be used to provide geothermal energy to local towns. This is the conclusion of two engineers from the University of Oviedo, whose research is being published in the journal Renewable Energy. The method they have developed makes it possible to estimate the amount of heat that a tunnel could potentially provide.
One way of making use of low-intensity geothermal energy is to convert mine shafts into geothermal boilers, which could provide heating and hot water for people living nearby", Rafael Rodríguez, from the Oviedo Higher Technical School of Mining Engineering, tells SINC. This type of energy, which is hardly used in Spain, is obtained from the internal heat of the Earth.
The engineer and his colleague María Belarmina Díaz have developed a "semi-empirical" method (part mathematical and part experimental) to calculate the amount of heat that could be produced by a mine tunnel that is due to be abandoned, based on studies carried out while it is still in use.
"When the mine is still active one can access the tunnels easily in order to gather data about ventilation and the properties of the rocks, as well as to take samples and design better circuits, and even programme the closure of some sections in order to use them for geothermal energy production", says the engineer, who stresses that, although geothermal energy can be made use of once the mine is closed, "it is no longer possible by that stage to make any modifications, or to gather any useful data to evaluate and improve the system".
The study looks into geothermal exploitation of a two-kilometre-long mine shaft, in which the temperature of the rocks 500m below the surface is around 30º C. This is typical of many of the mining areas in Asturias, although it could also be applied to other parts of the world. Water could be forced in through tubes at 7º C and return at 12º C, a big enough heat gain to be of benefit to towns located above the mines.
Advantages of geothermal energy from mines
Rodríguez and Díaz highlight the benefits of building geothermal boilers in mine shafts in that, aside from their predictable energy production levels, they also function practically as an open tube system "but without any risk of heat contamination of aquifers".
Using geothermal energy also helps to reduce CO2 emissions, and is not dependent upon climatic conditions (unlike other renewable energies such as solar or wind power). Other advantages are that these facilities make use of a country's own resources, do not require new developments on large sites, do not pollute the immediate environment, and are believed to be profitable over the long term.
Geothermal energy can be used directly in family homes, housing developments, swimming pools, fish farms, industrial units and other buildings.
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Waste Water Treatment Plant Mud Used As 'Green' Fuel

ScienceDaily (July 31, 2009) — Scientists have shown that using mud from waste water treatment plants as a partial alternative fuel can enable cement factories to reduce their CO2 emissions and comply with the Kyoto Protocol, as well as posing no risk to human health and being profitable. These are the results of an environmental impact assessment.
Dependency on oil and coal could be coming to an end. Researchers from the Rovira i Virgili University (URV) have analysed the environmental and human health impacts of an alternative fuel that solves various problems simultaneously. This is the solid waste from the water treatment plants of large cities.
The scientists have carried out the first study into this method at a cement plant in Vallcarca (Catalonia), which has been producing cement for more than 100 years, and they confirm in the latest issue of the journal Environmental Science and Pollution Research that it is “the best option for getting rid of mud that would have had to be dumped elsewhere, while also powering the plant”.
“As this mud is already waste, burning it does not enter into the atmospheric CO2 emissions assigned to each country under the Kyoto Protocol”, José Luis Domingo, lead author of the study and director of the Toxicology and Environmental Health Laboratory at the URV, tells SINC.
This would enable plants producing cement, one of the most contaminating industries in terms of CO2 as well as emissions of dioxins, furans and heavy metals, to consume energy in a more environmentally-friendly way. Up to 20% of the fossil fuel energy used at the Catalan plant has now been substituted for the fuel from waste water treatment plant mud.
From an economic point of view, the scientists will not say that cement plants could increase their profits by using this method, but “they will not have to pay anything to exceed their agreed emissions”, the researcher points out. The economic benefits of this system also depend on the price of fuel.
One of the most important issues for the URV scientists is the reduction in environmental impact, and consequently the health risks for people living near the plants. The experiment with the mud has led to a 140,000 tonne reduction in CO2 emissions between 2003 and 2006, and will have limited the potential deaths from exposure to chemical pollutants. In addition, the study shows that using this green fuel would reduce the cancer rate by 4.56 per million inhabitants.
The researchers say it is essential to carry out separate studies for each plant because “we still don’t know whether this will be positive for the whole cement industry”, according to Domingo. However, if the conditions are right, using mud from waste water treatment plants in cement factories is “a very good solution”, he concludes.
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