Tag Archives: study

Shorties: garlic as a guilty pleasure

Garlic is one of those things you can’t be indifferent about. You either love it, hate it, or love and hate it. This is exactly the reason why 100 Helsinki shoppers were interviewed and asked what they think abut garlic, and how much they are annoyed by it, compared to other social odors.

The most common belief was that garlic has a good taste, is healthy, but has an unpleasant smell. Users and non-users showed distinctly different belief patterns. However, it wasn’t nearly as unpleasant as researchers were expecting it to be. The most annoying social smells were considered to be sweat and alcohol, while garlic and aftershave were considered the least annoying.

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Energy drinks can cause alcohol dependence

One of the “highlights” of being a student or a young employee is having to stay up at night and study and/or do a lot of work. When coffee alone just won’t cut it, many turn to energy drinks. However one of the most common practices regarding energy drinks is mixing them with alcoholic beverages. The problem is that the contents of energy drinks aren’t regulated, and since they’re highly caffeinated they can lead to numerous problems, in addition to losing sleep.

A recent research concluded that people who drink energy drinks often, like 52 times per year or more (once per week) are at a significantly greater risk of alcohol dependence and episodes of heavy drinking. The results will be published only in February 2011, in the issue of Alcoholism: Clinical & Experimental Research.

Amelia M. Arria, the lead author of the study, Director of the Center on Young Adult Health and Development at the University of Maryland School of Public Health, and a Senior Scientist at the Treatment Research Institute claims that this study will help combat alcoholic addiction (in some cases), as well as energy drinks addiction.

“We were able to examine if energy drink use was still associated with alcohol dependence, after controlling for risk-taking characteristics. The relationship persisted and the use of energy drinks was found to be associated with an increase in the risk of alcohol dependence.”

Red Bull, one of the most popular energy drinks was temporarily banned in France

Here’s my personal take on it. The thing is, college students often consume energy drinks; which of course they have to buy first. And you never buy exactly what you need for the day, you always get a little more, to save for later. Which means you pretty much always have energy drinks at home, which temps you to have just a shot of energy whiskey, which of course leads to another shot, and so on. But mixing alcohol with caffeine doesn’t cancel or alter it’s effects, it just disguises them.

“Caffeine does not antagonize or cancel out the impairment associated with drunkenness—it merely disguises the more obvious markers of that impairment,” says Kathleen Miller, a research scientist from the Research Institute on Addictions at the University at Buffalo.

“Also needed is research that directly assesses students’ reported reasons for mixing alcohol and energy drinks. Anecdotal reports suggest that part of this phenomenon may be driven by the perpetuation of myths (e.g., mixing alcohol and caffeine reduces drunkenness, prevents hangovers, or fools a breathalyzer test) that could be debunked through further education.”, she adds.

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Whales suffer from sun burns too

You know those days when you go to the beach, and it’s just too hot outside, so you have to use some cream and all ? Well, it’s a little harder if you’re a whale. A recent study conducted that a whole lot of whales displayed blisters caused by sun damage.

Laura Martinez-Levasseur, from the Zoological Society of London (ZSL) and Queen Mary, University of London studied more than 150 whales from the Gulf of California, by taking pictures as well as skin samples; she explained that whales are a good model for studying marine animals, because “they need to come to the surface to breathe air, to socialise and to feed their young, meaning that they are frequently exposed to the full force of the sun”.

Examining the high res pictures they located the blisters and then put the skin samples under the microscope. The results were conclusive: the blisters were caused by sun burns. They also found something else, that paler coloured whales are more exposed to this kind of damage. Darker whales have more cells that produce a dark pigment called melanin. In humans, this is the result of a slight DNA altering caused by sun burn, and all signs seem to indicate the same thing in other mammals.

“This is the first evidence that the Sun’s rays can cause skin lesions in whales,” said Ms Martinez-Levasseur.
“The increase in skin damage seen in blue whales is a matter of concern, but at this stage it is not clear what is causing this increase. A likely candidate is rising ultraviolet radiation as a result of either ozone depletion, or a change in the level of cloud cover.”

The similarities to humans don’t stop here though. Professor Edel O’Toole, a skin specialist also involved in the study said:

“As we expect to see in humans, the whale species that spent more time in the sun suffered greater sun damage. We predict that whales will experience more severe sun damage if ultraviolet radiation continues to increase.”

The study showed no signs of skin cancer, but research is still going on. Other marine animals are also exposed to this kind of burns, especially hairless animals, like dolphins for example. The damage is also more serious in the areas with more ozone depletion, especially in the poles.

All life on earth could come from alien zombies

That’s right people, all the life on this beautiful planet (yep, that includes you) could descend from alien zombies. Well, this is indeed a slight imagination leap, but what I’m talking about are viruses; dead viruses, to be more exact. Dead viruses who contained information, enough information to pave the way for lifeforms to appear.

The theory of panspermia suggests that life on Earth came from outer space, on comets or meteorites or even on dust grains; this theory has been around for more than a century, when Lord Kelvin suggested that microbes could have come from comets. However, most astrobiologists believe that radiation would be fatal for the microbes in case.

“That essentially kills panspermia in the classical sense,” said astrobiologist Rocco Mancinelli of the SETI Institute in Mountain View, California.

But maybe panspermia doesn’t have to die; maybe our zombie viruses could save it (yes, zombies is definitely not the best word, but it sounds too damn cool). Paul Wesson, a visiting researcher at the Herzberg Institute of Astrophysics in Canada argues that even the microbes are dead on arrival, the information they carry can still allow life to rise from the charred remains.

“The vast majority of organisms reach a new home in the Milky Way in a technically dead state,” Wesson wrote. “Resurrection may, however, be possible.”

The key here is how much genetic information survives; genetic information can be quantified just like hard disk space. For example, a bacteria such as E. coli carries about 6 million bits of information in their DNA. Random chemical processes can only produce 194 bits of information over 500 million years, which couldn’t suffice for even a single cell. So how can this paradox be solved ?

“It must be admitted that all versions of panspermia suffer from a hole in our knowledge, concerning how to go from an astrophysically delivered entity which contains substantial information to one which has the characteristics of what we normally regard as life,” he wrote.

He pinpointed the virus as a good source however; they can carry about 100.000 bits of information, which would be more than enough. David Morrison, the director of the Carl Sagan Center for the Study of Life in the Universe admits that the “looks good, and interesting, although of course highly speculative”.

“The critical issue is whether the information in broken strands of nucleic acid could serve as the template for life on another world … since we know so little about the actual process by which life originated on Earth, who can really say?”

There are of course those who challenge this idea – Mancinelli is one of them.

“Once you’re dead, you’re dead,” he said. “It’ll give off enough radiation that it’ll just chop up all the nucleic acids,” he said. “There’s no way the organism will survive. Going from Earth to Mars, not a problem,” he said. “Even going from Earth to Pluto, or from Pluto to Earth, not a problem. But once you start heading out of the solar system, it’s so far away that it takes a long time. That’s the thing, the length of time.”

Scientists uncover amazing species 7000 m below water level

This amazing snailfish is just one of the animals new to science that have been uncovered by Oceanlab scientists; the expedition was studying one of the world’s deepest trenches, an environment thought to be void of fish of any kind, but researchers were surprised to find out that even the bottom of the trench was quite lively.

The marine biologists from Aberdeen, Tokyo and New Zealand shed some new light on the global distribution of fish and marine life on the globe, as well as discover new species never known before, such as large crustacean scavengers.

During the three week expedition they took a total of 6000 images between 4500 and 8000 meters below sea level; this expedition is the latest in a project that has been going on for three years, and proved to be by far one of the most successful so far. The new findings give us a new understanding of the depths at which fish can survive, as well as the diversity of species that can survive in such extreme environments.

Dr Alan Jamieson from the University of Aberdeen’s Oceanlab, who led the expedition said:

“Our findings, which revealed diverse and abundant species at depths previously thought to be void of fish, will prompt a rethink into marine populations at extreme depths.

“This expedition was prompted by our findings in 2008 and 2009 off Japan and New Zealand where we discovered new species of snailfish known as Liparids – inhabiting trenches off Japan and New Zealand at depths of approximately 7000m — with each trench hosting its own unique species of the fish.

For only the 2nd time in history, mankind has erradicated a virus

Scientists working for the UN reported today that they have erradicated the Rinderpest virus, a virus that is deadly for cattle. Rinderpest would be only the second virus erradicated by mankind, after smallpox. It caused massive damage in the Middle East, Africa and Asia, having a survival rate of only 10-20%.

Relax, cows.

The UN’s Food and Agriculture Organization (FAO) said they will stop their efforts to track and destroy the virus, after the announcement was made. The erradication is said to be the biggest veterinarian achievement in history, and will ultimately feed and save millions of people.

Dr John Anderson from the Institute for Animal Health (IAH) at Pirbright, UK said:

“For too long people have been involved in controlling diseases and not actually dreaming that it is possible to eradicate a disease from the world. And with Rinderpest we did.”

However, a formal announcement has yet to be announced, and it will probably have to wait until next year, when it will be made by the World Organisation for Animal Health (OIE).

Dr. Anderson and his colleagues developed a simple method to test the cattle and see if they had the disease; the test proved to be very effective, and it spread around Africa like wildfire. Rinderpest is (or was) one of the most deadly cattle viruses in history, so it’s erradication is indeed a huge achievement.

“It’s an enormously important achievement because it highlights what can be done by people working together,”Dr Mike Baron of the IAH told BBC. “It has also taken a disease which has been a huge threat to the livelihood of people and removed it.”

Earth-like planet may not exist

After an exciting discovery of a habitable earth-like planet, skepticism settles back in as a second team of scientists casts some doubt on the claim. Nicknamed Gliese 581 g, the planet in case stirred up the scientific world, promising to be the holy graal of exoplanets after it was discovered by Steven Vogt of the University of California, Santa Cruz, Paul Butler of the Carnegie Institution of Washington in DC, and their colleagues.
However, a second team of astronomers have looked in their own data and failed to find anything suggesting the existence of Gliese.

“We easily recover the four previously announced planets, “b”, “c”, “d”, and “e”. However, we do not see any evidence for a fifth planet in an orbit of 37 days,” said Francesco Pepe of the Geneva Observatory in Switzerland.

He presented his team’s results at the International Astronomical Union symposium in Turin, Italy. The two teams worked with data collected by HARPS, an instrument mounted on a telescope in the European Southern Observatory in Chile. Vogt and Butler’s team reached the results they did by combining 119 star velocity measurements from HARPS with 122 measurements taken with a similar instrument called HIRES (located in Hawaii). Pepe on the other hand used some extra data, and examined some 180 star velocity measurements collected by HARPS, which is significantly more than what Vogt and Butler used. So where does this leave our habitable planet ?

Gliese may or may not exist. Even though Pepe foundno evidence of it’s existence, they cannot rule out the possibility that it exists.

“We are not trying to prove the nonexistence of a planet,” Pepe says. “It’s really difficult to prove that something does not exist. We are just saying we do not see a significant signal that is really different from noise.”

This paper raises some serious questions about the discovery. Steven Vogt, who didn’t attend the astronomy symposium did not want to make any comments before he analyzes this new data. But he did tell New Scientist that he is not the least bit surprised by this turn of events.

“I am not overly surprised by this as these are very weak signals, and adding 60 points onto 119 does not necessarily translate to big gains in sensitivity,” Vogt told New Scientist.

He also confirmed the trust he has in the paper he previously published – and with good reason.

“I feel confident that we have accurately and honestly reported our uncertainties and done a thorough and responsible job extracting what information this data set has to offer,” Vogt added. “In 15 years of exoplanet hunting, with over hundreds of planets detected by our team, we have yet to publish a single false claim, retraction, or erratum.”

First rocky habitable Earth-like planet

A recently discovered planet is just about the right size and is in the right place to host life; as a matter of fact, astronomers seem quite sure it hosts life, and we’re talking more than microbes. Still, current technology doesn’t allow scientists to search for chemical markers of life.

About 20 light years away, it revolves around a red dwarf, and has been nicknamed Gliese 581g – the “g” stands for Goldilocks.

“Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say that the chances for life on this planet are 100 percent. I have almost no doubt about it,” Steven Vogt, professor of astronomy and astrophysics at University of California Santa Cruz, told Discovery News.

The discovery comes as a result of an 11 year program to get as much information as possible with ground-based instruments and telescopes; these instruments work by measuring minute variations caused by gravitational tugs of orbiting planets.

Red Dwarf

“This is really the first ‘Goldilocks’ planet, the first planet that is roughly the right size and just at the right distance to have liquid water on the surface,” astronomer Paul Butler, with the Carnegie Institution in Washington, D.C., told reporters during a conference call Wednesday.

“Everything we know about life is that it absolutely requires liquid water,” he added. “The planet has to be the right distance from the star so it’s not too hot, not too cold… and then it has to have surface gravity so that it can hold on to a substantial atmosphere and allow the water to pool.”

The planet is roughly three times larger than Earth, so it’s big enough to hold an atmosphere. It’s also quite old, and even more interesting, it’s tidally locked to the Sun, in a similar fashion to the Moon locked to the Earth: the planet’s star always ‘sees’ the same side, which is perpetually warmer and lighted, while the other one is dark and cold. As a result, temperatures are pretty stable, and vary greatly, which also encourages life.

“This planet doesn’t have days and nights. Wherever you are on this planet, the sun is in the same position all the time. You have very stable zones where the ecosystem stays the same temperature… basically forever,” Vogt said. “If life can evolve, it’s going to have billions and billions of years to adapt to the surface.”

“Given the ubiquity of water, it seems probable that this thing actually has liquid water. On the surface of the Earth, everywhere you have liquid water you have life,” Vogt added.

Astronomers seem quite convinced that many more such planets will be discovered in the not so distant future, and we will be entering a new stage in studying Earth-like planets.

“That being said, it is so close and we have found this thing so soon that it suggests we will start finding a lot of these things in the future and eventually we will find systems that do transit. This is a harbinger of things to come.”

The research will be published in the Astrophysical Journal

Large Hadron Collider hints at infant Universe

Despite several setbacks and technical difficulties, the Large Hadrdon Collider is already starting to live up to it’s nickname, the Big Bang machine. Researchers have pinpointed what may very well be the dense, hot state state of matter that is believed to have filled the Universe during its first nanoseconds.

Generally speaking, quarks are bound together in groups of two or three, stuck together by gluons. However, right after the Big Bang, it was so hot that the quarks broke free, and the matter became a free flow of quarks and gluons.

In the snapshots taken from LHC’s detector, a flow similar to this has been observed.

Full report here.

The first autist had quite a life

I recently came across a great article written by The Atlantic which I strongly suggest you read, about the first man who was diagnosed with autism. Now 77 years old, Donald Triplett has had quite a life !

He is a damn good golf player and has visited over 30 countries in his life, went on a safari and played several PGA tournaments. This is a man whose biggest pleasure as a child was to spin other objects, as well as spin himself.

He also had numerous problems in mingling with society, but drew everyone’s attention when he calculated how many bricks there were in the local school just by looking at it. Just goes to show autists can take care of themselves sometimes, and quite well. You really should read the article, and spread it around to people dealing with autism.

Homer Simpson gene limits memory and learning ability ?

Researchers at Emory University School of Medicine have conducted a study showing that the deletion of a particular gene makes mice smarter by unlocking a mysterious part of the brain, thought to be totally unflexible until now. When the gene, RGS14, is disabled, mice learn how to figure out mazes faster and more effective than regular mice. They also show signs of better memory and improved overall mental abilty.

Since RGS14 seems to hold mice down, John Hepler, PhD, professor of pharmacology at Emory University School of Medicine have nicknamed it the “Homer Simpson” gene. The gene is located in one particular part of the brain, the CA2, which is a part of the hippocampus, a region known to be involved in learning and the forming of new memories. However, the CA2 area is still an unknown area for researchers.

What makes this whole study even more interesting is the fact that the RGS14 gene is also in humans, and probably has the same use as it does for mice.

“A big question this research raises is why would we, or mice, have a gene that makes us less smart – a Homer Simpson gene?” Hepler says. “I believe that we are not really seeing the full picture. RGS14 may be a key control gene in a part of the brain that, when missing or disabled, knocks brain signals important for learning and memory out of balance.”

Some of our sources have reported that Homer Simpson doesn't like this study

What’s even better is that there didn’t seem to be any negative side effects to the deactivation of the gene, but there are still some possibilities that have to be investigated before definitive conclusions are drawn.

“The pipe dream is that maybe you could find a compound that inhibits RGS14 or shuts it down,” he adds. “Then, perhaps, you could enhance cognition.”

Octopus with venom that works in freezing temperatures discovered

Boy, you just can’t have enough octopus, that’s for sure – they’re really amazing creatures, that often surprise us. Now, a venomous octopus living in the frozen waters of Antarctica is definitely awesome, but how is this useful?

Well, according to Bryan Fry, of the University of Melbourne, it is. He and his team have been studying how evolution changed the way this octopus hunts, as well as the nature of the venom. The way they do things is drill small holes into large, shelled prey and then inject the toxic saliva.

“We found that venom can work at sub-zero temperatures. It was quite remarkable to find how well octopuses have adapted to Antarctic life,” Fry said.

He also noted the remarkable diversity of the species, with specimens varying in size from as little as a few inches to several meters.

“Evolutionary selection pressures slowly changed their venom, which allowed them to spread into colder and colder waters and eventually spread into super-cold waters,” Mr Fry said. We want to see what cool and wonderful new venom components we can find out of these venoms that would be useful in drug development,” he said. Nature has designed a perfect killing weapon … they have such incredibly accurate activity that there has to be a way to harness that. To tweak it or modify it or just use one little chunk.”

If we take a look at hypertension drugs (such as ACE inhibitors) that are modeled after snake venom, and other diabetes drugs (modeled after lizard saliva), it is understandable where the benefits of this study could pop up.

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The Domesticated Dog’s Ability to Interpret Human Social Cues is a Result of Millennia of Selective Breeding

man-looking-like-bulldog

As if the domesticated dog’s position as, “man’s (or woman’s) best friend” was not entrenched in the human zeitgeist enough, research from Brian Hare out Harvard’s Anthropology department indicates that not only are dogs far more adept than Chimpanzees- our closest genetic, extant relative- at interpreting human social cues, but that domesticated dogs are superior to wolves- their closest genetic, extant relative- in this respect, too.

The explanation reached by Hare is thus, “…dogs’ social-communicative skills with humans were acquired during the process of domestication.;” which occurred, because, “…dogs that were able to use social cues to predict the behavior of humans more flexibly than could their last common wolf ancestor … were at a selective advantage.”

In coming to this conclusion, Hare et al. performed four experiments, each pertaining to three hypotheses concerning the genesis of the domesticated dog’s social cognition. The experiments were centered around the Object Choice Task (OCT), where a subject- be it a dog, puppy, or chimpanzee- is presented with two boxes. Hidden underneath one the boxes is a treat (usually a piece of food); and because the box eliminates the possibility of detecting the food by either sight or smell, the subject relies on its ability to interpret the researchers indication (any combination of a gaze, point, or tapping of the box) to choose correctly.

The first of the three hypotheses, The Canid Generalization Hypothesis, posits that many canids, especially wolves, should perform well at OCT tasks because, “…[wolves] typically live in cooperative hunting social groups, making it likely that they need to exploit the behavior of conspecifics [other wolves] and quarry alike, and this ability may then generalize to humans.” The second, “Human Exposure” hypothesis, places the domesticated dog’s ontogeny forefront, implicating their social cognition as the result of having been exposed to humans for their entire lives. Lastly, the Domestication Hypothesis attributes dogs and humans pre-historic relationship as the vehicle of dogs developed ability to interpret human signals: the ability to interpret correctly human intentions, or at least more so than other individuals, was a positive trait. And that over the course of dog and humans 10 millennia long shared history (or, “paraell phylogeny,” if you’d like to be technical), these traits were exacerbated and honed.

Each of these hypotheses possesses logical corollaries. For example, it follows from Canid Generalization that wolves should to as well, or very nearly so, as dogs in OCTs; according to the Human exposure hypothesis puppies reared by humans should outperform their kennel reared peers in OCTs; and if the Domestication Hypothesis were true, dogs should perform well at OCTs regardless of age, since the ability to distinguish human social cues should be greatly inborn (and outperforming Chimpanzees doesn’t hurt to bolster this hypothesis either). By systematically comparing adult dogs and wolves, human reared puppies and kennel reared puppies, and adult dogs and chimpanzees performances at combinations of OCTs, Hare and colleagues were able to shed two of the hypothesis, which left the domestication hypothesis as the clear winner.

Of course, and this is the author writing, our ancestors probably did not selectively breed their dogs on the basis that they could find a hidden piece of food (which is undetectable by direct smell or sight) based on their gesticulations. The most conspicuous answer is that this specific trait (adeptness at OCT tasks) is a function of a dog’s ability to do work. After all, what good is the herding dog that herds on caprice, indiscriminately of his or her owner’s wishes? Simply, humans and canines have benefited from one another for thousands of years, and this relationship is based (like any good relationship) on clear communication. The fact that dogs have retained this ability (because it’s doubted that many of us use our “labradoodles” to herd) is a testament to the two species intimately intertwined lineage. And in the author’s opinion, so long as man (or woman) want their best friend by their side, this trait will persist for another ten millennia.

Storm elves and sprites recorded on video

Storm elves and sprites are electric luminous fleeting phenomena that sometimes naturally occur in the upper atmosphere. A team of Spanish researchers managed to make a high speed recording of the phenomena and publish it in the Journal of Geophysical Research. Practically, sprites are electrical discharges shaped like a carrot or a column that form in the mesosphere, at about 50-80 km above the ground. Elves are electrical rings that light the base of the ionosphere, at 80-700 km.

storm-elves

“This is the first time in Europe that we have been able to use high-speed video to detect transitory luminous phenomena taking place in the upper atmosphere — so-called sprites (in the form of a carrot or column) and elves (which are ring shaped),” Joan Montanyà, co-author of the study and a researcher at the Department of Electric Energy at the Polytechnic University of Catalonia (UPC), said.

The film showed that there are fewer sprites that form over land than over sea, and it also shed some light on their dynamics and electric structure.

“All these phenomena are related with storms, particularly winter storms, but they only appear in mesoscale convective systems (usually in large fronts), which produce lightning with high levels of energy or extreme electric currents,” explains Montanyà.

If you think you have food allergies… well… you probably don’t

allergy-wheel1A new study has shown that most people who think they have food alergies (over 80% in fact) actually don’t suffer from such problems. This has taunted some doctors for years and years, and AOL Health looked into this misdiagnosis. The study concluded that it is in fact a number of factors that lead to this dramatic overestimation of this condition.

“When someone is allergic to something, their immune system responds the way it might if it were infected with a parasite,” says Hugh A. Sampson, professor of pediatrics and dean for translational biomedical sciences at the Jaffe Food Allergy Institute at the Mount Sinai School of Medicine Department of Pediatrics.

However, this can often be hard to detect, because symptoms are not extremely clear most of the time and responses can be misinterpreted. However, testing is not the main issue, as researchers point out.

“The problem is not with the test,” says Sampson, whose own food allergy research has yielded results similar to those of the NIAID study. “The test is good at telling us whether someone has an allergic antibody, but the test then needs to be interpreted as to whether or not the individual will actually react.”

Most things remain unknown about allergies, but this researcher has pointed out that a more thorough examination of the patient is in order before making him take on a food challege, which is often time consuming and unpleasant. Read the rest of the study here.

Photosynthesis – not just for plants anymore

cyano

As any fourth grader will tell you, photosynthesis is (in layman terms), the process through which plants (and bacteria, algae, etc) get the sugars and other organic compounds they need using energy from sunlight. However, during last week’s synthetic biology conference in Boston, a biologist from Harvard took things to a whole new level, presenting a new and exciting idea: he injected a symbiotic cyanobacteria responsible for almost 50 percent of Earth’s photosynthesis into a fish.

He chose a zebra fish for this, because they are clear, which makes them excellent candidates for this kind of research. So they injected bacteria into fish embryos, and waited. The results ? Nothing special happened – which is amazing ! Both the fish and the bacteria grew normally, as you can see in the video here.

The bacteria didn’t generate enough energy to sustain the fish on its own, but it provided a well received nutritional boost. Pamela Silver, a biologist from Harvard, is leading a team that is working on methods to increase the cyanobacteria production. So does that mean that we’ll have photosinthetic animals, or even humans in the near future? Absolutely not. But when dealing with these kind of ideas, the near future means nothing; and in the more distant future? Why not…

TV has a negative long term impact on toddlers

ctoddlertv03_02-773242

If you want your kids to be healthier, thinier and smarter, then you probably should keep them away from TVs while they’re toddlers. A recent (and quite shocking) joint study conducted by Université de Montréal, the Sainte-Justine University Hospital Research Center and the University of Michigan revealed that television exposure at ages of 2 and under have significant negative impacts, including unhealthy habits and poor school adjustment.

“We found every additional hour of TV exposure among toddlers corresponded to a future decrease in classroom engagement and success at math, increased victimization by classmates, have a more sedentary lifestyle, higher consumption of junk food and, ultimately, higher body mass index,” says lead author Dr. Linda S. Pagani, a psychosocial professor at the Université de Montréal and researcher at the Sainte-Justine University Hospital Research Center.

The study analyzed over 1300 children, with the goal of determining the impact TV has on future academic succes and social involvement, and the results were quite dire.

“Between the ages of two and four, even incremental exposure to television delayed development,” says Dr. Pagani.

“Early childhood is a critical period for brain development and formation of behaviour,” warns Dr. Pagani. “High levels of TV consumption during this period can lead to future unhealthy habits. Despite clear recommendations from the American Academy of Pediatrics suggesting less than two hours of TV per day — beyond the age of two — parents show poor factual knowledge and awareness of such existing guidelines.”

Here’s just a quick look at the numbers caused by watching too much tv at that age:

– a seven percent decrease in classroom engagement;
– a six percent decrease in math achievement (with no harmful effects on later reading);
– a 10 percent increase in victimization by classmates (peer rejection, being teased, assaulted or insulted by other students);
– a 13 percent decrease in weekend physical activity;
– a nine percent decrease in general physical activity;
– a none percent higher consumption of soft drinks;
– a 10 percent peak in snacks intake;
– a five percent increase in BMI.

“Although we expected the impact of early TV viewing to disappear after seven and a half years of childhood, the fact that negative outcomes remained is quite daunting,” says Dr. Pagani. “Our findings make a compelling public health argument against excessive TV viewing in early childhood and for parents to heed guidelines on TV exposure from the American Academy of Pediatrics.”

Complete Neanderthal genome sequenced

Yes ladies and gents, researchers have produced the whole genome sequence of the 3 billion “letters” (nucleotides) in the Neanderthalian genome, and the results are interesting to say the least. For starters, up to 2 percent of present day human DNA outside of Africa originated in Neanderthals; this result suggests that the Neanderthals, Homo neanderthalensis diverged from the same primate line that led to nowadays humans, homo sapiens.

neanderthal

However, some 400.000 years ago, they migrated to northern Eurasia, where they became genetically isolated and evolved differently than the other human line. Approximately 30.000 years ago however, the Neanderthals dissappeared. Still, they are our closest relative, considering we share an ancestor from some 800.000 years ago. For example, the chimpanzees diverged from the same line 5-7 million years ago.

“This sequencing project is a technological tour de force,” said NHGRI Director Eric D. Green, M.D., Ph.D. “You must appreciate that this international team has produced a draft sequence of a genome that existed 400 centuries ago. Their analysis shows the power of comparative genomics and brings new insights to our understanding of human evolution.”

In order to achieve their goals, researchers analyzed DNA from three females that lived some 40.000 years ago (pretty close to the extinction date). This provided the first “genome-wide look” at the similarities and unsimilarities between humans and our “relative”. They results showed that Neanderthal DNA is 99.7% identical to our own, and 98.8% identical to that of the chimpanzee (the same number is correct for human-chimp DNA comparison).

“The genomic calculations showed good correlation with the fossil record,” said coauthor Jim Mullikin, Ph.D., an NHGRI computational geneticist and acting director of the NIH Intramural Sequencing Center. “According to our results, the ancestors of Neanderthals and modern humans went their separate ways about 400,000 years ago.”

“It was a very unique series of events, with a founding population of modern humans of greatly reduced size — tens to hundreds of individuals,” Dr. Mullikin said.

They know this because geneticists can detect if the population constricts, identifying several genetic markers that are ore cnocentrated.

At that time,” Dr. Mullikin continued, “where the population was greatly reduced, the modern humans migrating out of Africa encountered Neanderthals and inter-breeding occurred between the two groups, leaving an additional, but subtle, genetic signature in the out-of-Africa group of modern humans.”

As homo sapiens spread across Europe and not only, they carried with them Neanderthal DNA – and spread it. So it’s no surprise then that 2 percent of the genomes of present-day humans living from Europe to Asia was inherited from them. The team however, did not find those traces of DNA in people in Africa.

“The data suggests that the genes flowed from Neanderthal to modern humans,” Dr. Mullikin said. “That had to have occurred at least once during the 20,000 to 30,000 years, in which modern humans and Neanderthal both lived on the Eurasian continent.”

However, the team said they need more samples in order to improve and expand their results.

“These are preliminary data based on a very limited number of samples, so it is not clear how widely applicable these findings are to all populations,” said Vence L. Bonham, Jr., J.D., senior advisor to the NHGRI Director on Societal Implications of Genomics. “The findings do not change our basic understanding that humans originated in Africa and dispersed around the world in a migration out of that continent.”

UPDATE: Researchers at the Max Plank Institute in Leipzig, Germany have recently released (2013) a high-detail genome of a Neanderthal specimen for open access. This will hopefully advance our understanding of Neanderthals and how they relate to modern man.