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Researchers at the University of California, Davis, recently identified a powerful scent produced by both humans and birds that apparently lures Culex mosquitoes to their next blood meal.

The source, a substance called nonanal, emits a fruity or floral odor and also is made commercially, used in manufacturing perfumes and flavors. When given off in the air, nonanal works synergistically with carbon dioxide, another known mosquito attractant, to send a strong message to the biting insects. Mosquitoes detect smells with the olfactory receptor neurons of their antennae.
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“Nonanal is how they find us,” said Walter Leal, a professor of entomology and leader of the research team.

“Mosquitoes are very sensitive to this compound,” he added. “It’s a very common chemical produced by humans and animals, and also industry. It’s everywhere.”

The discovery ultimately could lead to new ways of controlling mosquitoes, which carry disease-causing viruses, including West Nile virus. A West Nile infection can result in serious neurological illness. Mosquitoes from the Culex family--the focus of this study--carry West Nile.

Birds, the main host of mosquitoes, are a reservoir for West Nile. The insects transmit viruses to humans--as well as to birds, horses, dogs, cats, bats, chipmunks, squirrels and domestic rabbits--when they bite and take a blood meal.

“If you can decrease the biting of mosquitoes, you can decrease the incidence of disease,” Leal said.

Leal and postdoctoral researcher Zain Syed screened hundreds of naturally occurring compounds emitted by multiracial and multiethnic humans, and multiple species of birds, including chickens and pigeons. They collected chemical odors from 16 human subjects, including two African Americans, two Chinese, eight Caucasians, three Latinos and one East Indian, who ranged in age from 20 to 55.

They found varying amounts of the substance among the individuals, but everyone produced it. “We didn’t find anybody in our samples who was completely depleted of the compound,” Leal said.

They also baited mosquito traps with a combination of nonanal and carbon dioxide. “We were drawing in as many as 2,000 a night in Yolo County, near Davis,” Syed said. “Nonanal, in combination with carbon dioxide, increased trap captures by more than 50 percent, compared to traps baited with carbon dioxide alone.”

The researchers believe that nonanal results from the breakdown of dietary fatty acids. Eliminating the intake of fatty acids, however, is not the answer to preventing mosquito bites, Leal said. “You can’t get rid of fatty acids,” he said. “We need them.”

Moreover, finding ways to block nonanal may not be the route to mosquito control. First, humans produce varying levels of the substance and scientists do not yet know the effects of different amounts on mosquito behavior. In fact, in some cases insects are drawn by small amounts of attractants, while repelled by high amounts.

“We know there are variations in how much nonanal humans produce, but we don’t know whether they are related to more or less attraction,” Leal said. “We want to go back to the field and try different doses of nonanal to see if mosquitoes are attracted by more levels - or whether there is a point where the attraction starts to decline.”

Furthermore, researchers also need to learn more about the body’s natural repellants, since these, too, likely play a role in controlling mosquito bites. “It’s very common to hear stories about people who go into the field and one gets lots of mosquito bites, while another person doesn’t get any,” Leal said.

“All of us make natural repellants and attractants, so we could be dealing with more than one compound,” he added. “Some of us may be very attractive to mosquitoes--not necessarily because we generate nonanal, but because we don’t generate the natural repellent. We don’t know all the chemicals yet. People are saying: ‘now you can mask nonanal and everything will be solved.’ It’s very appealing to say that, but it’s not that simple.”

In 2008 Leal and his team discovered how the insecticide DEET repels mosquitoes. Scientists had long thought that DEET, an insect repellent developed more than 50 years ago by the U.S. Department of Agriculture, works by masking a human’s smell or by jamming the insect’s senses, interfering with its ability to locate a host. But Leal showed that mosquitoes can smell DEET--and hate it. They avoid it simply because they dislike its odor.

The nonanal study, which was published in the Proceedings of the National Academy of Sciences, was funded by the National Science Foundation, the National Institutes of Health, and through a cooperative agreement with Bedoukian Research, a supplier of specialty aroma and flavor ingredients headquartered in Connecticut.

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Oliver Twist, one of the most famous works of Charles Dickens’, is a novel reflecting the tragic fact of the life in Britain in 18th century.

The author who himself was born in a poor family wrote this novel in his twenties with a view to reveal the ugly masks of those cruel criminals and to expose the horror and violence hidden underneath the narrow and dirty streets in London.

The hero of this novel was Oliver Twist, an orphan, who was thrown into a world full of poverty and crime. He suffered enormous pain, such as hunger, thirst, beating and abuse. While reading the tragic experiences of the little Oliver, I was shocked by his sufferings. I felt for the poor boy, but at the same time I detested the evil Fagin and the brutal Bill. To my relief, as was written in all the best stories, the goodness eventually conquered devil and Oliver lived a happy life in the end. One of the plots that attracted me most is that after the theft, little Oliver was allowed to recover in the kind care of Mrs. Maylie and Rose and began a new life. He went for walks with them, or Rose read to him, and he worked hard at his lessons. He felt as if he had left behind forever the world of crime and hardship and poverty.

How can such a little boy who had already suffered oppressive affliction remain pure in body and mind? The reason is the nature of goodness. I think it is the most important information implied in the novel by Dickens-he believed that goodness could conquer every difficulty. Although I don’t think goodness is omnipotent, yet I do believe that those who are kind-hearted live more happily than those who are evil-minded.

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Like millions of other Americans, I often have trouble with insomnia — either I can't fall asleep, or I awake prematurely and am unable to get back to sleep. The following sleep tips, compiled from various sources, may prove helpful to some of my fellow insomniacs.

Only use your bed for sleeping or having sex, not for reading, doing paperwork, watching TV, snacking, or making phone calls.
If you've been lying in bed but are beginning to fear you're not going to drop off, try some of these techniques: Count sheep or count backwards from 100 (one of my favorites) to stop yourself from thinking about the problems of yesterday or tomorrow; breathe deeply for awhile; or visualize some peaceful place.
If you can't get to sleep after lying in bed for 30 minutes or more, get up for awhile. What to do? Try reading something incredibly boring.
Develop a bedtime routine.
Keep regular bedtime hours.
Before bedtime, avoid tobacco and caffeinated beverages (not just coffee, but other drinks like tea, cola, and Dr. Pepper).
Avoid alcohol right before bedtime — a nightcap might get your mind fuzzy enough to put you to sleep, but such sleep may be interrupted by periods of awakening. By contrast, the stress-lowering effect of a drink with dinner may help to promote sleep later.
Avoid naps (or falling asleep in front of boring TV programs, as I do).
Try to get up at the same time every day rather than sleeping in on weekends.
Exercise every day, but not shortly before bedtime since exercise gets the adrenaline going.
If you use an illuminated clock for a wakeup alarm, place it where you can't     * keep looking at it to check the time.
Buy a firm mattress and keep your bedroom well ventilated (a cool temperature works best for me).
And you might also try some of these: a warm bath, warm milk, light bedtime snack, massage, or quiet music (which turns itself off automatically).
Use earplugs for extreme quiet.
If you have a painful joint or a headache, take a pain pill before bedtime (but be sure it doesn't contain caffeine).
Avoid stimulating reading or television shows late at night.

If the insomnia stubbornly persists, check with your doctor to make sure some underlying health problem (such as depression, anxiety, hyperthyroidism, heart failure, or chronic obstructive pulmonary disease) isn't keeping you awake. If all is well, you might ask for one of the several types of prescription sleeping pills that can be useful in the short term.

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That fact is cited in a new analysis of academic scientists and housework -- being published today by Academe, the magazine of the the American Association of University Professors, and calling for colleges to create an option for faculty members and others to have financial assistance for housework as an employee benefit. The study finds that even among dual career scientist couples, the time gap spent on housework is hindering the advancement of women.
The study found that female scientists with male partners perform 54 percent of their family housework (cooking, cleaning and laundry) in their households, while male scientists with female partners perform 28 percent of their family housework. While there are other tasks on which the male scientists contribute a majority of time (yard, house and car care), those tasks take much less time a week than those that women are more likely to perform. It adds up to a 10-hour drain on the time of female scientists, the study finds.

The study was conducted by Londa Schiebinger, the John L. Hinds Professor of History of Science and director of the Clayman Institute for Gender Research at Stanford University, and Shannon Gilmartin, a quantitative analyst and the institute. The data come from a large research project at the institute, "Dual Career Academic Couples: What Universities Need to Know." Schiebinger and Gilmartin used data collected for that report from 1,222 tenured and tenure-track faculty members in the natural sciences at leading universities. Those studied were all partnered with someone of the opposite sex. (Data were also collected from same-sex couples, but the totals were too small to draw conclusions on them.)

Among the other findings:
Male scientists with stay-at-home partners do the least household work, relying on their female partners to do 76 percent of such work.

While very few women in the survey (13) have stay-at-home male partners, they do more housework than their male counterparts.
The men and women in the study reported nearly identical hours a week at work -- mean of 56.4 hours for men and 56.3 hours for women.

Men and women who employ others to do housework are more productive than those who don't employ others. (Productivity is measured by number of published articles.)

Based on these findings, the authors suggest that colleges recognize that housework is "an academic issue" and revise benefits packages accordingly. They suggest that institutions offer flexible packages of benefits, in which financial assistance for housework would be one possible benefit. They write that some employees might not want the benefit and would prefer, based on their personal or family situations, other benefits. But the option should be included, they write.

"One appealing aspect of this benefit proposal is its inclusivity -- one need not be partnered or have children to gain access," they write.

Schiebinger and Gilmartin acknowledge that, given the economic downturn, this may not be "the right time" to propose a major expansion of benefits. But they say that over the long run, this is an issue that should be addressed.

"Providing benefits to support housework continues dominant social trends of the past 40 years," they write. "U.S. institutions have stepped into the domestic sphere to support aspects of private life, from health-care benefits to child-care supplements. Institutions now need to step in to support housework."

Cathy A. Trower, research director and co-principal Investigator of the Collaborative On Academic Careers in Higher Education, at Harvard University, said she wasn't surprised by the findings on housework. But she said she feared that this may not be the issue that most needs reform.

"I'm all for more benefits for faculty and household help would be great for everyone -- singles and marrieds and men and women. Bravo," she said.

But the larger question is whether such changes would actually help many women (and men). COACHE's surveys of young faculty members have found significant frustrations with work/family balance in higher education, but the surveys have also found many young scholars who don't just want more help, but want different models, with more time for family or non-academic pursuits.

Too much attention to issues like housework may shift attention away from broader reforms, Trower said. She has written about the need for different models for faculty careers -- long-term renewable contracts, tenure expectations that may not require 60 hours a week in the lab and so forth -- as the best way to create more options. Focusing on benefits -- such as how many times you can stop the tenure clock or whether you should be paid for hiring household help -- doesn't address the question of whether the system is one to bolster or needs real reform.

"What I am against is the lack of flexibility and the seeming inability to confront openly the issues at play," she said.

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On Thursday 10 April 1919, the charismatic revolutionary leader Emiliano Zapata was assassinated.

His corpse was slung over the back of a mule, transported to the state capital, where it was officially identified, embalmed, and then photographed, before being subject to a hasty burial. Like Zapata himself, the photograph has had a lively posthumous career in Mexican cultural history.

Andrea Noble, Durham University, tells the story of the death and afterlife of Emiliano Zapata through the making and dissemination of this fascinating photograph, exploring its reproduction in the national press in 1919, and more recent re-workings of the image that testify to Zapata’s mythic status as a latter-day secular saint.

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Families now stuffing backpacks and greeting the children's new teachers face a crisis that makes falling test scores and rising college costs dull by comparison. Ten years and billions of dollars into the fight against childhood fat, it's clear that the campaign has been a losing battle. According to a report released last week by the research group Trust for America's Health, one third of kids nationwide are overweight now; other stats show that the percentage of children who are obese has more than tripled since the 1970s. Now, experts are worrying about the collateral damage, too: A 2006 University of Minnesota study found that 57 percent of girls and 33 percent of boys used cigarettes, fasting, or skipping meals to control their weight and that diet-pill intake by teenage girls had nearly doubled in five years. Last year, nearly 5,000 teens opted for liposuction, according to the American Society of Plastic Surgeons—more than three times the number in 1998, when experts first warned of a "childhood obesity epidemic."

"We've taken the approach that if we make children feel bad about being fat or scare them half to death, they'll be motivated to lose excess weight," says Joanne Ikeda, nutritionist emeritus at the University of California-Berkeley, who studies pediatric obesity prevention. "It hasn't worked in adults, so what makes us think it will work in kids?" Many experts now believe that an emphasis on dropping weight rather than adding healthful nutrients and exercise is doing more harm than good.

Failure to end—or even slow—the epidemic has public-health experts, educators, and politicians in a near panic. All told, some 17 percent of kids are now obese, which means they're at or above the 95th percentile for weight in relation to height for their age; an additional 17 percent are overweight, or at or over the 85th percentile. This is despite massive government-funded education campaigns in schools, in libraries, and on TV to alert parents and kids to the dangers. "In the early 1980s, I used to see one or two kids a year with type 2 diabetes, and now I see one or two a month," says Alan Lake, an associate professor of pediatrics at the Johns Hopkins University School of Medicine. "Evidence now suggests that this type 2 diabetes progresses more rapidly in kids, which means we could be soon seeing 20-year-olds developing severe heart disease." Already, high blood pressure affects more than 2 million youngsters.

Long haul. Obesity is hard to outgrow, so about 50 percent of elementary-school kids and 80 percent of teens who are obese will battle the scales—and the greatly increased risk of disease—for the rest of their lives. A number of authorities have warned that today's youth could be the first ever to have a shorter life span than their parents.

What explains both the problem and the elusiveness of a solution? Blame the American "toxic environment." Cinnamon buns and candy are far cheaper and easier to sell at the local mall than, say, a fresh fruit cup or a packet of sliced almonds. Half of kids walked or biked to school a generation ago; today, only about 10 percent do—then they come home and plop down in front of their various screens. As if the inactivity weren't bad enough, preteens absorb more than 7,600 commercials a year for candy, sugary cereal, and fast food, according to the Kaiser Family Foundation. "They're surrounded by circumstances where the default behavior is one that encourages obesity," says Marlene Schwartz, deputy director of the Rudd Center for Food Policy and Obesity at Yale University. Busy parents contribute by stocking pantries with quick energy—sugary cereal, Fruit Roll-Ups, and Oreos—while bringing home Kentucky Fried Chicken for dinner.

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The Advisory Board Company has launched a new division—the Education Advisory Board—to provide best practice research and advice to leading colleges and universities, both in the U.S. and abroad. Strategic Research Analysts work with research teams to give shape to book-length analyses that address the major strategic, management and operational issues facing higher education today. Strategy studies document and summarize the company's findings on best (and worst) demonstrated practices in higher education. Analysts assist in the conception, research, analysis writing and presentation of two to four research studies per year.
Analyst, Strategic Research in Higher Education

The Company—Nation’s Preeminent Provider of Best Practice Research

Named by Washingtonian Magazine as one of Washington, DC's Best Places to Work, The Advisory Board Company (NASDAQ: ABCO) is the nation’s leading provider of best practice research and advice to the U.S. health care industry, serving a membership of more than 2,800 hospitals, health systems, insurers and pharmaceutical companies. Each year the Advisory Board publishes 55 major studies and more than 10,000 customized research briefs, and conducts more than 1,000 onsite briefings for its members. The research focuses on identifying the best (and worst) management practices and strategies across the industries we serve.

The Role in Brief—Best Practice Research in Higher Education

The Advisory Board Company has launched a new division—the Education Advisory Board—to provide best practice research and advice to leading colleges and universities, both in the U.S. and abroad. Strategic Research Analysts work with research teams to give shape to book-length analyses that address the major strategic, management and operational issues facing higher education today. Strategy studies document and summarize the company's findings on best (and worst) demonstrated practices in higher education. Analysts assist in the conception, research, analysis writing and presentation of two to four research studies per year.

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Scientists are developing mind-to-machine technology that could enable people who cannot speak to communicate using their own brain waves and a computer screen.

Recently, neuroscientists at the Mayo Clinic campus in Jacksonville, Fla., demonstrated that brain waves, focusing on a matrix of letters, can project letters onto a monitor - with the goal of eventually typing out words and sentences. For example, by concentrating on the letter "q," that "q" will appear on the screen.
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The technique requires a craniotomy - that is, a surgical incision into the skull - to place electrodes directly onto the surface of the brain. The implanted devices then record electrical activity produced by the firing of nerve cells.

The research is preliminary. However,  it potentially could help millions of people with disorders that result in speech loss, such as, Amyotrophic Lateral Sclerosis - Lou Gehrig's disease - a progressive deterioration of voluntary muscle movement; spinal cord injuries that require a breathing tube;  and "locked-in syndrome," where patients are awake and aware - but are paralyzed everywhere but the eyes. Even certain stroke patients could benefit, the researchers said.

"We want to emphasize that this really is at the beginning," said Jerry Shih, MD, the Mayo scientist who, with Dean Krusienski, PhD., of the University of North Florida, studied the technology in six epilepsy patients.  Still, "I think the potential applications are wide-ranging," he added. "We want to make this a practical type of device that will have an impact on their function, and quality of life."

While researchers have used the technology in the past to see whether such signals could control prosthetic devices, such as arms, this  is believed to be the first research that examines its potential for language.

The researchers studied the technique in epilepsy patients with existing electrodes that had been implanted earlier to monitor their seizures. "These people already had electrodes in their brains, so we didn't have to subject them or anyone else to invasive brain surgery," Shih said.

The scientists wanted to see whether the process was more effective when electrodes were implanted directly onto the surface of the brain - electrocorticography (ECoG) - compared with those placed only on the scalp, known as electroencephalography (EEG.)  The ECoG technique proved faster and more accurate.

"There was a big difference in the quality of information," Shih said. "With EEG, the electrical signals are significantly distorted as they pass through the skin, the scalp fat, the bony skull - all those layers. There just wasn't as clear a signal, compared to ECoG.  Imagine someone with Lou Gehrig's disease trying for five minutes to type out a word, and finding errors in that word. The accuracy wasn't optimal."

In the study, patients sat in front of a monitor that was hooked to a computer running the researchers' software, which was designed to interpret electrical signals coming from the electrodes. The patients looked at the screen, which contained a 6-by-6 matrix with a single letter inside each square. Each time the square with a certain letter flashed, and the patient focused on it, the computer recorded the brain's response to the flashing letter. Then the patients focused a specific letters and the computer software recorded the information.

The computer then calibrated the system with the individual patient's specific brain wave and - when the patient then focused on a letter - the letter appeared on the screen.

If perfected, the technology could help people "with any neurologic disease that impacts a person's ability to effectively communicate, as long as they can attend to the task," Shih said, adding: "It won't work, for example, in people who are demented."

Even certain stroke patients - those whose attack occurred in the brain stem - could benefit, Shih said. "Those patients can't talk because the pathway to the speech area has been interrupted by the stroke, but the actual center that produces language - the cerebral cortex -  is not involved," he said.

It might even be possible to apply the technology to stroke victims whose language center has been injured. Other areas of the brain may be able to compensate, Shih said. "We actually found that these types of signals can be reported not only from the language center, but from other portions of the brain," he said. "So this still might work even for people whose language area has been destroyed."

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We'll spare you the lecture. (Seriously, though. Stamp out that butt and flush the pack, already.) Tobacco use, namely cigarette smoking, is the chief cause of preventable death in the United States. Left unbridled, smoking could kill more than a billion people this century, according to the World Health Organization. That equals the number who would die if a Titanic sank every 24 minutes for the next 100 years, as former U.S. Surgeon General C. Everett Koop so starkly put it at a March press conference.
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Still, it may be harder than ever to quit: Three quarters of today's smokers trying to shed the habit are heavily hooked on nicotine, up 32 percent from almost two decades ago, according to research presented at the American College of Chest Physicians' annual meeting in October. So quitting, for most, is not merely a matter of willpower. Nonetheless, the reasons to do so keep amassing—and they're not all about heart disease, lung cancer, or respiratory problems. Here's a few downsides you might not have considered

1. It fogs the mind. Smoking may cloud the mind, according to accumulating research. A June study in the Archives of Internal Medicine found that smoking in middle age is linked to memory problems and to a slide in reasoning abilities, though these risks appeared lessened for those who'd long quit; this is important, the authors wrote, because other research has shown that people with mild cognitive impairment in midlife develop dementia at an accelerated rate. Their report piggybacks on several focused on the older set: A 2007 analysis of 19 prior studies concluded that elderly smokers face a heightened risk of dementia and cognitive decline, compared with lifelong nonsmokers. And in 2004, researchers reported in Neurology that smoking appeared to hasten cognitive decline in dementia-free elderly smokers, bringing it on several times faster than in their nonsmoking peers.

2. It may bring on diabetes. As if we need any more risk factors for diabetes, an analysis published in the Journal of the American Medical Association last year found that across 25 prior studies, current smokers have a 44 percent greater chance of developing type 2 diabetes than nonsmokers do, and the risk was strongest for those with the heaviest habit, who clocked 20 or more cigarettes per day. In an accompanying editorial, researchers made a striking estimation: That some 12 percent of all type 2 diabetes cases nationwide might be attributable to smoking.

3. It invites infections. In October, the federal Advisory Committee on Immunization Practices made its first ever recommendation that all smokers ages 19 to 64 be added to a short list of candidates for the pneumococcal vaccine. That's because there are very strong data showing that the risk of infection by pneumonia-causing bacteria is substantially greater for smokers than for nonsmokers, says Pekka Nuorti, a medical epidemiologist at the Centers for Disease Control and Prevention. Exactly why is unclear, though there's evidence that smoking may damage the respiratory system's protective mucous membranes, making it easier for infectious organisms to latch on and cause disease, says Nuorti. Other research suggests that smoking may interfere with immunity, compromising people's ability to fight infections, he adds.
Heightened susceptibility to infections, it appears, isn't limited just to those who do the smoking: A May study in Tobacco Control found that children exposed to secondhand smoke at home during early infancy (especially those born prematurely or with a low birth weight) are more prone to a throng of severe illnesses that may land them in the hospital at some point during childhood. The findings were based on an analysis of more than 7,000 Chinese children from 1997 to 2005.

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Depression is an illness that causes you to feel sad, to lose interest in activities that you've always enjoyed, to withdraw from others, and to have little energy. It's different from normal feelings of sadness, grief or low energy. Depression can also cause people to feel hopeless about the future and even to think about suicide.

Many people, and sometimes their families, feel embarrassed or ashamed about having depression. Don't let these feelings stand in the way of getting treatment. Remember that depression is a common illness. Depression affects the young and old, men and women, all ethnic groups, and all professions.

If you think you may be depressed, tell your doctor. Treatment can help you enjoy life again. The sooner you get treatment, the sooner you will feel better.

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