Do you know why outdoor activity protects children from myopia?

Prof. Know Why answers for your general knowledge and awareness on: Do you know why outdoor activity protects children from myopia?

We all know that the more children are allowed to play outdoor sports, the better it is for their health in the growing days. But a recent study found that time spent outdoors even protects children against myopia.

The study has suggested that time spent in the open appears to protect children from near-sightedness, adding a new factor for a common condition that has long been blamed on extensive reading or genes.

Researchers at the University of Sydney, Australia, believe the intensity of outdoor light may be an important, but till now unrecognized, factor that influences the development of myopia, which usually begins during school years.

“Increasing outdoor activity may be a way to counter factors that might be contributing to myopia,” said Kathryn Rose, an ophthalmologist who led the study that involved more than 4,000 schoolchildren in Australia. It was published last week in the journal Ophthalmology.

The researchers found that 12-year-olds with the highest outdoor activity had the lowest rates of myopia, independent of the amount of reading or other near work they did. Myopia was most common in children with low levels of outdoor activity and high near work.

Long hours of indoor playtime or sports had no effect on myopia levels. “It appears to be the effect of intense light,” Rose said.

Myopic eyes are mildly elongated, front to back. The scientists believe that in response to light, the retina releases a chemical called dopamine and prevents eye elongation. The pupils also constrict in intense light, increasing the distance at which objects can be seen.

Near-sightedness has long been attributed to genetics. Children with parents who have myopia are at risk. “But we still can’t say whether it’s the effect of genes or whether the parents create an environment that promotes myopia,” Rose said.

“What has held out over the years is that children with strong scholastic achievements tend to have myopia. Our new study shows that children who do a lot of schoolwork and spend time outdoors appear protected.”

Independent studies in the US and Singapore appear to support these findings, she said.

The researchers have recommended more studies to try and establish the connection more firmly, and explore the mechanism of how exposure to daylight by means of outdoor activity, can prevent myopia.

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Do you know why women love men with self-deprecating humor?

Miss Finder –The Journo, tries to find answers for your general knowledge and awareness on: Do you know why women love men with self-deprecating humor?

Hey guys, you would simply love this, because I’m going to give you yet another clue to win your woman’s heart. Well, being a woman myself, I always like honest men with good sense of humor. And, I’m not alone – confirms the latest study! So, what's the most effective way of winning a woman's heart? Well, it is by running yourself down! Yes, you read it right – women, in general, just love men with self-deprecating humor!

I’m sure you guys would find it hard to digest, but guys, this is now a proven fact. Researchers have carried out the two-year study which revealed that taking the mickey out of one's self, works better than just clever jokes which might be seen as boastful and put women off.

Lead researcher Gil Greengross said, “Many studies show that a sense of humor is sexually attractive, especially to women. But we've found that self-deprecating humor is the most attractive of all. It is a risky form of humor because it can draw attention to one's real faults thereby diminishing the self-deprecator's status in the eyes of others. But based on the idea that verbal humor evolved to function as a fitness indicator, self-deprecating humor can be an especially reliable indicator, not only of general intelligence and verbal creativity, but also moral virtues such as humility.”

In fact, in the study into the role of humor in seduction, the researchers have found that the type of humor used by Hugh Grant in the film Notting Hill, in which he attempts to charm Julia Roberts with the poor contents of his fridge - works the best.

But beware guys, before taking the plunge because the London researchers have also warned that the technique should not be attempted by those who are already unpopular as it could make “low-status individuals” appear “more pathetic” than they did before.

The study is to be published in the upcoming edition of the Journal of Evolutionary Psychology.

So, it’s not the smartest of the men with the most intelligent sense of humor that attract this present age women, instead, men with self-deprecating humor, make their way into their hearts. Are you listening, guys?

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Do you know why bees lose their buzz?

Prof. Know Why answers for your general knowledge and awareness on: Do you know why bees lose their buzz?

Like humans, the insect world also experiences problem in performing their routine jobs, when sick. Bumblebees lose a bit of their buzz when ill, and like humans, have a tougher time doing daily tasks until they recover, according to British researchers who reported their findings in the Royal Society's journal, Biology Letters, last week.

Evolutionary biologist Eamonn Mallon of the University of Leicester, who believes his findings can boost the efforts in saving dwindling bee colonies, said Honeybees with activated immune systems also have memory problems. He said that bees live on their memory. And, "If even a minor infection hurts its memory that is a major cost."

Like humans, bees can get sick and recover in days from infections after the immune system kicks into action to fight off viruses or parasites, Mallon said.

The researchers divided bees into two groups and injected half with a substance that stimulated the immune system. They then offered the bees the choice of blue and yellow flowers but only one color contained sugar water.

Eventually all the bees spent their time feeding from the correct flower but it took the stimulated bees 10 percent longer to reach this point, showing that an active immune response when ill affects memory, the researchers said.

In the past 50 years different kind of bee species and their population have become sparse day by day throughout the world and several are under threat. Scientists believe, apart from the farming methods that have deprived bumblebees of many traditional flowering plant food sources, diseases may help explain the decline.

Well, this can lead to serious concern about both the decline in wild bumblebee species and the effects of disease on the honeybee industry, of course if you care to give your ears!

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Do you know why delayed fatherhood can cause miscarriage?

Prof. Know Why answers for your general knowledge and awareness on: Do you know why delayed fatherhood can cause miscarriage?

Couples who want to start a family, better plan it early in your life because the more you delay, the stronger becomes the risk of a miscarriage, say the scientists. And this applies to both men and women. Contrary to the older belief that men remain fertile even at old age, this new research points out that delayed fatherhood can also cause miscarriage like late motherhood.

Delayed fatherhood for men is a cause of concern for a healthy pregnancy and the baby as well, doctors warn, after a recent research found that male fertility begins to decline when they reach their mid-30s. Doctors said men who wait until their 40s before starting a family face a greater chance of their partner having a miscarriage, because of the poorer quality of their sperm.

The researchers studied the records of more than 12,000 couples treated for infertility at the fertility clinic, Eylau Centre for Assisted Reproduction in Paris between January 2002 and December 2006; and separated out the influence of male and female ages on the couples' chances of having a baby. They found that women whose partners were 35 or older had more miscarriages than those who were with younger men, regardless of their own age. The men's ages also affected pregnancy rates, which were lower in the over-40s.

The study looked at pregnancies and miscarriages recorded for couples having IUI treatment at the clinic. It found the risk of miscarriage was on average 16.7% when men were aged 30-34. That rate rose to 19.5% when men were 35-39 and 33% in men aged 40 or over.

The findings are a concern, researchers say, because of the trend for men to delay fatherhood. Stéphanie Belloc, lead author of the study, said that until now, gynecologists only focused on maternal age, and the message was to get pregnant before the age of 35 or 38 because afterwards it would be difficult. But now the gynecologists must also focus on paternal age and give this information to the couple.

Yves Ménézo, an embryologist at the Eylau Centre for Assisted Reproduction, said older men become less fertile because genetic defects build up in their sperm. In younger men, the damage is minor and can be repaired inside the fertilized egg. But in older men the amount of DNA damage can overwhelm the body's natural repair mechanisms. "We think there's a critical threshold of DNA damage and above that, the damage can no longer be repaired. When that happens, genetic mistakes get through to the embryo and you get an increase in miscarriages," Ménézo said.

Jacques de Mouzon, a co-author at the French National Institute for Medical Research, said: "People say men are fertile into old age, 90 even. That may be true sometimes, but the product is different and there are more semen abnormalities as age advances. There is a decrease [in male fertility] and an increase in the spontaneous abortion rate after the age of 40 and especially after 45. It is necessary for men to try to have children before the ages of 40 to 45."

Previous research has pointed to a slight increase in birth defects in babies born to older men. A 2005 study of 70,000 couples by epidemiologist Jorn Olsen at the University of California, Los Angeles, found a fourfold rise in Down's syndrome among babies born to men aged 50 and older. They were also more likely to have limb deformities.

Dr Allan Pacey, a fertility expert at Sheffield University and secretary of the British Fertility Society, said: "There is growing evidence from a number of studies to show that men are not totally immune from reproductive ageing. "Previous studies of couples trying to conceive naturally or undergoing IVF have shown that men over the age of about 40 are less fertile than younger men. Moreover, if they do achieve a pregnancy their partners are more likely to miscarry. This study reinforces the message that men aren't excused from reproductive ageing."

Normally, men don't typically worry about reproductive ageing, but perhaps they should if the study is to be believed, as now, delayed fatherhood is also being linked to miscarriages, and birth deformities.

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Do you know why women are more attracted to men with stubble?

Miss Finder –The Journo, tries to find answers for your general knowledge and awareness on: Do you know why women are more attracted to men with stubble?

All young men, do you know what it takes to get into a woman’s heart? Well, stubble is the way to win a woman’s heart, so says a study. Researchers found that women are more attracted to men with stubble than those with clean-shaven faces or full beards.

The findings of the experiment, carried out on British women aged 18 to 44, could explain the appeal of actors such as George Clooney and Brad Pitt who cultivate their unshaven look.

Women who participated in the research rated men with stubble as tough, mature, aggressive, dominant and masculine — and as the best romantic partners, either for a fling or a long-term relationship.

To justify this preference of women, the experts in human evolution have given a weird explanation, that facial hair may be a signal of aggression because it boosts the apparent size of the lower jaw, emphasizing the teeth as weapons. An unusual and funny reasoning, if you ask me — isn’t it?

Well, psychologists at Northumbria University, who actually carried out the new study, explain differently. They believe that stubbly men may offer women the best worlds — not too strongly masculine, but mature and with the potential to grow a full beard.

The researchers carried out the study using computer technology to alter pictures of 15 men’s faces so that they displayed different degrees of hairiness. Five levels were used — clean-shaven, light stubble, heavy stubble, light beard and full beard.

The pictures were shown to 76 women who were asked to rate them for masculinity, aggression, dominance, attractiveness, age, and social maturity.

Pictures of men with full beards were judged to be the most masculine, aggressive and socially mature. But they were rated the least attractive and the worst choice for a short-term relationship.

Men with light beards were considered the most dominant. Those with light stubble were rated the most attractive and as the ideal romantic partner for the short or long term. Clean-shaven men finished bottom for masculinity, dominance, aggression, and social maturity.

Well, gone are the days, when women used to like her man to be elegant with clean-shaven look. The 21^st century women are more attracted to the rough macho look instead, that signifies more masculinity in men with stubble. And if you ask me, I simply find stubbly men, hot — yes, that’s the word! So get ready guys — now you know the way to a woman’s heart!

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Do you know why chimpanzees hug and kiss?

Prof. Know Why answers for your general knowledge and awareness on: Do you know why chimpanzees hug and kiss?

In humans, a nice hug and some sympathy can normally help a bit after we get pushed around. Now, it’s known that chimpanzees also use hugs and kisses the same way. And it works! Researchers studying human's closest genetic relatives, the chimpanzees, found that stress was reduced in chimpanzees who were victims of aggression if a third chimpanzee stepped in to offer consolation.

The findings were reported recently in the Proceedings of the National Academy of Sciences. The research was done by Dr. Orlaith N. Fraser of the Research Center in Evolutionary Anthropology and Paleoecology at Liverpool John Moores University in England; and colleagues. They studied chimpanzees at the Chester Zoo in England from January 2005 to September 2006, recording instances of aggression such as a bite, hit, rush, trample, chase or threat.

Dr. Fraser said that the research showed, "consolation usually took the form of a kiss or embrace", which is particularly interesting because this behavior is rarely seen other than after a conflict. "If a kiss was used, the consoler would press his or her open mouth against the recipient's body, usually on the top of the head or their back. An embrace consisted of the consoler wrapping one or both arms around the recipient."

The result was a reduction of stress behavior among the chimpanzees, such as scratching or self-grooming by the victim of aggression, reported Dr. Fraser and colleagues.

Dr. Frans de Waal of the Yerkes Primate Center at Emory University in Atlanta, who was not part of Fraser's research team, said, the study is important because it shows the relationship between consolation and stress reduction in the chimpanzees.

"This study removes doubt that consolation really does what the term suggests: provide relief to distressed parties after conflict. The evidence is compelling and makes it likely that consolation behavior is an expression of empathy," Dr. Waal said.

Dr. Waal suggested that this evidence of empathy in chimpanzees is "perhaps equivalent to what in human children is called 'sympathetic concern.'"

That behavior in children includes touching and hugging of distressed family members and "is in fact identical to that of apes, and so the comparison is not far-fetched," he said. But, while chimpanzees show this empathy, monkeys do not, he added.

Previous research on conflict among chimpanzees concentrated on cases where there were reconciliation between victim and aggressor, with little attention to intervention by a third party.

The latest research result shows that chimpanzees calm distressed recipients of aggression by consoling them with a friendly gesture. But, consolation is most likely to occur, that is by hugs and kisses, between chimpanzees who already have valuable relationships, concludes chief researcher Dr. Orlaith N. Fraser.

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Do you know why children are at risk from passive smoking?

Prof. Know Why answers for your general knowledge and awareness on why children are at risk from passive smoking:

Babies, infants and children on the whole don’t smoke or so do we think! But, the reality says something different. In fact, infants and children belonging to smoker parents are forced to smoke because of ignorance by the latter – yes, I’m talking about passive smoking! But do you know about the consequences?

Well, children who are exposed to secondhand tobacco smoke that is passive smoking, early in life are at greater risk of being hospitalized for infections than those brought up in a smoke-free environment, researchers from Hong Kong reported, recently.

The risk of being hospitalized was greatest among babies 6 months old and younger, but the increased risk persisted up until the children were 8 years old, Dr. M. K. Kwok of the University of Hong Kong and colleagues found in their research. Children who were premature or had low birth weight were particularly vulnerable.

The findings suggest that passive smoking exposure may not only be harmful to children's respiratory tracts, but to their immune systems as well, the researchers Kwok and colleagues noted in their report in the journal Tobacco Control.

Even if smoking is banned in public places, babies and children may still be exposed to passive smoking at home. So, the risks remain.

While the danger that passive smoking poses, to children's developing respiratory systems is well understood, less is known about its effects on overall infection risks. To investigate, the researchers looked at a group of 7,402 children born in 1997 who were followed up until age 8. At the study's outset, nearly 42% were exposed to passive smoking at home.

Children who had been within 3 meters (or about 9.8 feet) of a person smoking cigarettes at any point during their first 18 months of life were 14% more likely to be hospitalized for any type of infection by 8 years of age, the researchers found.

The greatest difference was seen among infants, with 1 in 3 exposed babies being hospitalized for an infection by the time they were one year old. Exposure during the first 3 months of life had the strongest effect.

Premature and low birth weight infants seemed to be more vulnerable to the effects of passive smoking and they were twice as likely to be hospitalized for an infection by age 8 than unexposed children.

The researchers concluded that passive smoking exposure in early infancy, instigates all infectious illnesses and not just respiratory and related infections. And again, this may even have a larger and more long-lasting impact in developmentally more vulnerable subgroups, such as premature or low birth weight infants.

So, if you fall among the ignorant smoker parent’s group, just do bother to keep your children away from passive smoking, at least from now on – that is of course, if you care! Gift your children a smoke-free home and not hospital!

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Do you know why women may have diminished libido?

Prof. Know Why answers for your general knowledge and awareness on why women may have diminished libido:

Are you having problems in your sex life? Is your woman having diminished libido? Well, she may be suffering from pelvic floor disorder, which may impact women's sex life!

Incontinence and other disorders of the pelvic organs can take a toll on a woman's sex life, a new study suggests.

Researchers found that among 300 women aged 40 and above, those with symptoms of a pelvic floor disorder were more likely to have a diminished libido, pain during sex, or problems reaching orgasm.

Pelvic floor disorders refer to problems with a woman's pelvic organs - the uterus, bladder and rectum; and the muscles and connective tissue that support them. Among the most common of these are urinary incontinence and pelvic organ prolapse, where weakened muscles and supporting tissue allow one or more pelvic organs to drop down and protrude into the vagina.

Some symptoms of prolapse include pressure in the vagina, pain in the lower abdomen or lower back, and chronic constipation.

It has been estimated that one-third of U.S. women have at least one type of pelvic floor disorder, but studies have come to conflicting conclusions as to whether the conditions hinder women's sex lives.

The new findings, reported in the journal Obstetrics & Gynecology, suggest that many women with these disorders, do in fact, have problems with sexual function.

However, the risk of sexual dysfunction was not elevated among women who had mild prolapse that was not causing symptoms, said lead researcher Dr. Victoria Handa, an associate professor of gynecology and obstetrics at Johns Hopkins University in Baltimore. This is important, she explained, because it indicates that women who have sexual complaints but no other potential symptoms of pelvic organ prolapse do not need to be evaluated for the disorder.

The findings are based on 301 patients recruited from gynecology offices affiliated with Johns Hopkins. Eighty women were seeking care for a pelvic floor disorder, including bladder control problems and pelvic organ prolapse. The rest of the women had other conditions or were getting a routine checkup. All of the women completed questionnaires on their overall health, pelvic symptoms and sexual function.

Overall, the researchers found, women with pelvic floor disorders were more likely to have symptoms of a diminished libido, pain during sex and infrequent orgasms - regardless of age and whether they had gone through menopause.

According to the findings of an earlier study by Dr. Handa and her colleagues, women's diminished libido and sexual function are often improved after having surgery to correct significant prolapse.

So, women with pelvic floor disorders should talk it out with their doctors about any sexual difficulties they have. That may only help, improve their diminished libido.

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Do you know why erectile dysfunction is an early sign of heart disease?

Prof. Know Why answers for your general knowledge and awareness on why erectile dysfunction is an early sign of heart disease:

Erectile dysfunction and heart disease may seem to be two different problems, but recent findings from two studies of men with diabetes add to the evidence that erectile dysfunction can be a powerful early warning sign for serious heart disease.

A Hong Kong study of 2,306 men with diabetes but no signs of heart disease found that those with erectile dysfunction at the start were 58 percent more likely to have a heart attack or other major cardiac problems over the next four years than those with adequate sexual function.

And, Italian physicians who followed 291 men who had diabetes and early coronary heart disease for four years, reported similar numbers - those with erectile dysfunction were twice as likely as men without the problem to have major adverse events, including strokes.

There's a physical connection between male sexual failure and heart disease, involving the effect of diabetes on the nervous system and the blood vessels, said Dr. E. Scott Monrad, director of the Cardiac Catheterization Lab at Montefiore Medical Center in New York City. "Neuropathy would interfere with the neurogenic responses feeding into proper erection," Monrad said. "And obstruction of blood flow into the arteries reduces the pressure needed to achieve erection."

It has been known that erectile dysfunction shares many risk factors with coronary heart disease, such as high blood pressure, smoking and diabetes, according to Dr. Robert A. Kloner, a professor of medicine at the University of Southern California. "What is new here is that erectile dysfunction remained a significant risk factor for developing heart disease after controlling for other cardiovascular risk factors," Kloner said in a statement.

"These reports add two things to what we already know," said Dr. R. Parker Ward, an associate professor of medicine at the University of Chicago, who led an earlier study linking erectile dysfunction with heart disease. "One is that they indicate the importance of erectile dysfunction in diabetic patients in terms of predicting future cardiovascular events. These studies suggest that the additional presence of erectile dysfunction places them at incrementally higher risk. Secondly, they show that even when considered in combination with traditional risk factors, erectile dysfunction offers incremental information about the risk of future cardiovascular events."

The researches indicate that acknowledgment of erectile dysfunction can prompt doctors to suggest more aggressive treatment at an early stage for risk factors such as high blood pressure and cholesterol that may lead to heart diseases.

So, if you are having erectile dysfunction, talk it out with your physicians, since this may prove to be a very sensitive marker for cardiovascular risk. Remember, an early and more sensitive measure may save you from future heart risks.

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Do you know why smokers quit smoking?

Prof. Know Why answers for your general knowledge and awareness on why smokers quit smoking:

If you are a smoker, you may know that the urge to smoke is contagious, but did you know that quitting the puff is, too? Well, a team of researchers, recently, has found that contagious pattern with smoking cessation. They observed that a smoker is more likely to kick the habit of smoking if a spouse, friend, co-worker or sibling does so.

Moreover, the research showed that smokers tend to quit smoking in groups as those who don't stop puffing, increasingly find themselves pushed to the edge of their social circles.

"Your smoking behavior depends upon not just the smoking behavior of the people you know, but also the people who they know" and so on, said Dr. Nicholas Christakis, a medical sociologist at Harvard Medical School and lead author of the new report.

This latest study, by Christakis and his colleague James Fowler of the University of California, San Diego, which appeared in New England Journal of Medicine and was funded by the National Institute on Aging, focused on people's smoking habits in the social network.

The findings back up previous studies showing that peer influence plays a key role in smoker's decision to stop smoking and provide evidence that the "buddy system" used by smoking cessation, weight loss and alcoholism programs to change addictive behavior, works.

The researchers examined the social lives of 12,067 people in the Framingham Heart Study, which has been tracking the health of residents of that Boston suburb from 1971 to 2003. They were able to reconstruct people's ties to one another since participants had to list contact information for their family, friends, co-workers and neighbors so researchers would not lose track of them over the years. The prevalence of smokers in the Framingham study over the years mirrored national trends.

Not surprisingly, the greatest influence was seen in close relationships. When a spouse stops smoking, the other partner is 67 percent less likely to smoke. Similarly, when a friend quits smoking, the chance of the other, continuing to smoke, drops by 36 percent. The odds are similar among co-workers and siblings, also.

People who were connected to others by up to three degrees of separation were also influenced. If one person quits smoking, the chance of a person two degrees apart, stopping the smoking habit is 29 percent. In a three-degree separation, the chances are 11 percent.

"One person in the group gets the motivation to quit and it starts to cascade and ripple through the group," said Fowler.

Jill Palmer, 28, was a one-pack-a-day smoker until she checked into a cessation program last year at the University of Wisconsin, Madison where she works. She took nicotine gum and worked with a counselor to set a “quit date”. Several days after Palmer went smoke-free, her husband also threw away his last pack. "It was spurred by my timing. He didn't want to be a smoker anymore," said Palmer, who credits her nonsmoking co-workers with persuading her to enroll in the cessation program.

The researchers found, by analyzing random samples of smoking clusters, that whole groups became nonsmokers over time because people who remained smokers found themselves moving to the fringe of their social circles.

So, that says it all, why smokers quit smoking? –They are actually forced to!

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Do you know why exercise may protect girls from future breast cancer?

Prof. Know Why answers for your general knowledge and awareness on why exercise may protect girls from future breast cancer:

We are all aware of the fact that exercise is good for health. And middle-aged women have long been advised to get active to lower their risk of breast cancer after menopause. But, starting young, pays off, too. A new research shows, exercise during the teen years — starting as young as age 12 — can help protect girls from breast cancer when they're grown.

Dr. Graham Colditz of Washington University School of Medicine in St. Louis, the study's lead author, points out that the benefit of sustained physical activity from adolescence through the adult years, gets the maximum benefit.

Researchers tracked nearly 65,000 nurses, ages ranging from 24 to 42 who enrolled in a major health study. They answered detailed questionnaires about their physical activity dating back to age 12. Within six years of enrolling, 550 were diagnosed with breast cancer before menopause. A quarter of all breast cancer is diagnosed at these younger ages, when it's typically more aggressive.

Women who were physically active as teens and young adults were 23 percent less likely to develop premenopausal breast cancer than women who grew up sedentary, researchers reported in the Journal of the National Cancer Institute.

The biggest impact was regular exercise from ages 12 to 22.

The women at lowest risk of breast cancer, reported doing 3 hours and 15 minutes of running or other vigorous activity a week — or, for the less athletic, 13 hours a week of walking. Typically, the teens reported more strenuous exercise while during adulthood, walking was most common.

But, why exercise may protect girls from future breast cancer? How exactly, would it help? A big point of exercise in middle age and beyond is to keep off the pounds. After menopause, fat tissue is a chief source of estrogen.

In youth, however, the theory is that physical activity itself lowers estrogen levels. Studies of teen athletes show that very intense exercise can delay onset of menstrual cycles and cause irregular periods.

While the study examined only premenopausal breast cancer, "it's certainly likely and possible" that the protection from youthful exercise will last long enough to affect more common postmenopausal breast cancer, too, Colditz added.

Dr. Alpa Patel, a cancer prevention specialist at the American Cancer Society, who praised the new research, said that though the moderate exercise reported in this study of breast cancer was nowhere near enough for those big changes, but it probably was enough to cause slight yet still helpful hormone changes.

Dr. Patel believes that even if someone was a bookworm as a teen, it's not too late, because other researches on the middle-age benefits of exercise show, mom should join her daughters for that bike ride or game of tennis or at least a daily walk around the block.

There are quite a few breast cancer risks that a woman can't change, like:

• How early she starts menstruating
• How late menopause hits
• Family history of the disease

But, physical activity and body weight are such factors that women can control. Women who engage in physical activity not only during adolescence but also during adulthood, lower their risks of breast cancer, said Dr. Patel.

So, what are you still waiting for? If your young daughter is a bookworm or simply a TV buff, just simply get her off the couch.

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Do you know why global warming is the greatest threat to tropical species?

Prof. Know Why answers for your general knowledge and awareness on why global warming is the greatest threat to tropical species:

Global warming is the ultimate concern in today’s world, if you care! Nearly every other day, news headlines are flooded with the topic of global warming, although most of us are probably ignorant about the consequences that global warming can actually cause to living beings.

The latest research on global warming says that while global warming is expected to be strongest at the poles, it may be an even greater threat to species living in the tropics.

Tropical species are accustomed to living in a small temperature range and thus may be unable to cope with changes of even a few degrees, according to an analysis in the last week’s edition of Proceedings of the National Academy of Sciences.

The research was led by Tewksbury, an assistant professor of biology at the University of Washington and Curtis A. Deutsch, an assistant professor of atmospheric and oceanic sciences at the University of California, Los Angeles.

"There's a strong relationship between your physiology and the climate you live in. In the tropics many species appear to be living at or near their thermal optimum, a temperature that lets them thrive. But once temperature gets above the thermal optimum, fitness levels most likely decline quickly and there may not be much they can do about it," Joshua J. Tewksbury said in a statement.

Concern over global warming has largely focused on arctic species like the polar bear. But such animals may be accustomed to living in a wide range of temperatures, while there tends to be little change in the tropics, so there has been no need for species there to adapt.

"The direct effects of climate change on the organisms we studied appear to depend a lot more on the organisms' flexibility than on the amount of warming predicted for where they live," Tewksbury said. "The tropical species in our data were mostly thermal specialists, meaning that their current climate is nearly ideal and any temperature increases will spell trouble for them."

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Do you know why pollution keeps away bees from pollinating?

Prof. Know Why answers for your general knowledge and awareness:

Have you noticed lately that insects like bees and butterflies are gradually fading away in your neighborhoods? In a recent study, scientists found out why these wild populations of some pollinators, mainly bees, which need nectar for food, are fading in several areas of the world.

Researchers at the University of Virginia have shown that air pollution from power plants and automobiles is wiping out the fragrance of flowers and thus hampering the ability of bees and other pollinating insects to track scent trails to their source.

"The scent molecules produced by flowers in a less polluted environment, such as in the 1800s, could travel for roughly 1,000 to 1,200 meters; but in today's polluted environment downwind of major cites, they may travel only 200 to 300 meters," said Jose D. Fuentes, a professor of environmental sciences at the University of Virginia and a co-author of the study. "This makes it increasingly difficult for pollinators to locate the flowers," he added.

The result, potentially, is grave as bees and other pollinating insects like butterflies struggle to find sufficient food to keep up their populations and the flowering plants also do not get pollinated sufficiently to proliferate and diversify.

Other studies, as well as the actual experience of farmers, have shown that populations of bees, particularly bumblebees, and butterflies have declined greatly in recent years.

Researchers believe that air pollution, especially during the peak period of summer, may be a factor. To investigate this, they created a mathematical model of how the scents of flowers travel with the wind. They found the scent molecules, produced by flowers very volatile that quickly bond with pollutants such as ozone, hydroxyl and nitrate radicals, which destroy the aromas they produce.

This means that instead of traveling intact for long distances with the wind, the scents are chemically altered and the flowers, in a sense, no longer smell like flowers. This forces pollinators to search farther and longer and possibly to rely more on sight and less on smell.

From the research study, it became evident that air pollution destroys the aroma of flowers, by as much as 90 percent from periods before automobiles and heavy industries came into existence, And the more air pollution there is in a region, the greater the destruction of the flower scents, and the less pollinating insects like bees to balance the ecosystem.

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Do you know why English and Chinese languages affect dyslexia differently?

Prof. Know Why answers for your general knowledge and awareness:

Millions of children worldwide are affected by dyslexia, a language-based learning disability that can include problems in reading, spelling, writing and pronouncing words. According to the International Dyslexia Association, approximately 8 to 15 percent of the students worldwide (if not more) suffer from this problem.

But very recently an interesting finding, reported in the online edition of Proceedings of the National Academy of Sciences, opened up a new angle to look at the problem on the whole - Dyslexia affects different parts of children's brains depending on whether they are raised reading English or Chinese.

"This finding was very surprising to us. We had not ever thought that dyslexics' brains are different for children who read in English and Chinese," said lead author Li-Hai Tan, a professor of linguistics and brain and cognitive sciences at the University of Hong Kong. "Our finding yields neurobiological clues to the cause of dyslexia."

Reading an alphabetic language like English requires different skills than reading Chinese, which relies less on sound representation, using symbols to represent words.

Past studies have suggested that the brain may use different networks of neurons in different languages, but none has suggested a difference in the structural parts of the brain involved.

Tan's research group studied the brains of students raised reading Chinese, using functional magnetic resonance imaging. They then compared those findings with similar studies of the brains of students raised reading English.

The research speculates that different genes may be involved in dyslexia in Chinese and English readers. The new findings suggest that treating Chinese speakers with dyslexia may use working memory tasks and tests relating to sensor-motor skills, while current treatments of English dyslexia focus on letter-sound conversions and sound awareness.

In their paper, the researchers noted that imaging studies of the brains of dyslexic children using alphabetic languages like English have identified unusual function and structure in the left temporo-parietal areas, thought to be involved in letter-to-sound conversions in reading; left middle-superior temporal cortex, thought to be involved in speech sound analysis, and the left inferior temporo-occipital gyrus, which may function as a quick word-form recognition system. When they performed similar imaging studies on dyslexic Chinese youngsters, on the other hand, they found disruption in a different area, the left middle frontal gyrus region.

If anything, this new research finding will help treating this learning disability, more scientifically and the therapists may now seek different methods of assisting dyslexic children from different cultures.

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