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20 years in the making: Prospective Alzheimer’s drug builds new brain cell connections

20 years in the making: Prospective Alzheimer’s drug builds new brain cell connections | Amazing Science | Scoop.it

Washington State University researchers have developed a new drug candidate that dramatically improves the cognitive function of rats with Alzheimer’s-like mental impairment. Their compound, which is intended to repair brain damage that has already occurred, is a significant departure from current Alzheimer’s treatments, which either slow the process of cell death or inhibit cholinesterase, an enzyme believed to break down a key neurotransmitter involved in learning and memory development.

 

Such drugs, says Joe Harding, a professor in WSU’s College of Veterinary Medicine, are not designed to restore lost brain function, which can be done by rebuilding connections between nerve cells.

"This is about recovering function,” he says. "That’s what makes these things totally unique. They’re not designed necessarily to stop anything. They’re designed to fix what’s broken. As far as we can see, they work.”

 

Harding, College of Arts and Sciences Professor Jay Wright and other WSU colleagues report their findings in the online "Fast Forward” section of the Journal of Pharmacology and Experimental Therapeutics. Their drug comes as the pharmacological industry is struggling to find an effective Alzheimer’s treatment. Last month, the Pharmaceutical Research and Manufacturers of America, or PhRMA, reported that only three of 104 possible treatments have been approved in the past 13 years. "This 34 to one ratio of setbacks to successes underlines the difficulty of developing new medicines for Alzheimer’s,” the trade group said in a news release.

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A Planned Plane Crash Of A Boeing 727 To Yield Invaluable Scientific Information

A Planned Plane Crash Of A Boeing 727 To Yield Invaluable Scientific Information | Amazing Science | Scoop.it
In an unprecedented event, two pilots will board a Boeing 727, fly it over a vast, empty desert, set it to crash land and parachute from the plane. Filmed for Channel 4, the resulting high-speed crash will provide scientists with invaluable information about how planes react in potentially fatal accidents.

 

You can check in and choose a seat on our flight to discover how this choice would have affected your chances of surviving our crash. If you have checked in, you can retrieve your booking online to find out how you would have fared and learn more about on-board safety. Don’t worry, plane crashes are rare and it is extremely unlikely you will ever be involved in a real one. All crashes are different – the feedback you’ll receive on your seat choice is based on the analysis and knowledge of our crash experts and relates only to this particular crash.

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Human neural stem cells transplanted into brains of four boys with rare fatal brain disease

Human neural stem cells transplanted into brains of four boys with rare fatal brain disease | Amazing Science | Scoop.it

Four young boys with a rare, fatal brain condition have made it through a dangerous ordeal. Scientists have safely transplanted human neural stem cells into their brains. Twelve months after the surgeries, the boys have more myelin — a fatty insulating protein that coats nerve fibers and speeds up electric signals between neurons — and show improved brain function, a new study in Science Translational Medicine reports. The preliminary trial paves the way for future research into potential stem cell treatments for the disorder, which overlaps with more common diseases such as Parkinson’s disease and multiple sclerosis.

 

Without myelin, electrical impulses traveling along nerve fibers in the brain can’t travel from neuron to neuron says Nalin Gupta, lead author of the study and a neurosurgeon at the University of California, San Francisco (UCSF). Signals in the brain become scattered and disorganized, he says, comparing them to a pile of lumber. “You wouldn’t expect lumber to assemble itself into a house,” he notes, yet neurons in a newborn baby’s brain perform a similar feat with the help of myelin-producing cells called oligodendrocytes. Most infants are born with very little myelin and develop it over time. In children with early-onset Pelizaeus-Merzbacher disease, he says, a genetic mutation prevents oligodendrocytes from producing myelin, causing electrical signals to die out before they reach their destinations. This results in serious developmental setbacks, such as the inability to talk, walk, or breathe independently, and ultimately causes premature death.

 

Although researchers have long dreamed of implanting human neural stem cells to generate healthy oligodendrocytes and replace myelin, it has taken years of research in animals to develop a stem cell that can do the job, says Stephen Huhn, vice president of Newark, California-based StemCells Inc., the biotechnology company that created the cells used in the study and that funded the research. However, he says, a separate study by researchers at Oregon Health & Science University, Portland, found that the StemCell Inc. cells specialized into oligodendrocytes 60 percent to 70 percent of the time in mice, producing myelin and improved survival rates in myelin-deficient animals. So the team was able to test the cells’ safety and efficacy in the boys.

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Jooyeon Cho's curator insight, January 8, 2013 1:07 AM

This article is about human neural stem cell transplants that were done on the brains of 4 boys with rare, fatal brain conditions. The transplant was a success and has shown to improve the conditions of the boys. This transplant shows the potential that stem cell therapy holds and how it could vastly advance medical treatments.

Claire P-C's curator insight, January 23, 2013 7:26 AM

Promising results for patients! It would be highly interesting to assess the transplantation effects on these boys in few years.

 

For more information:

N. Gupta, et al., Neural Stem Cell Engraftment and Myelination in the Human Brain. Sci. Transl. Med. 4, 155ra137 (2012).

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The mysterious case of the missing noble gas Xenon in Earth's atmosphere

The mysterious case of the missing noble gas Xenon in Earth's atmosphere | Amazing Science | Scoop.it
Xenon has almost vanished from Earth's atmosphere. German geoscientists think they know where it went.

 

The evidence is in every breath of air, but answers are harder to come by. Xenon, the second heaviest of the chemically inert noble gases (after radon), has gone missing. Our atmosphere contains far less xenon, relative to the lighter noble gases, than meteorites similiar to the rocky material that formed the Earth. The missing-xenon paradox is one of science’s great mysteries. Researchers have hypothesized that the element is lurking in glaciers, minerals or Earth’s core, among other places.

 

Scientists went looking for answers in minerals. Magnesium silicate perovskite is the major component of Earth’s lower mantle — the layer of molten rock between the crust and the core, which accounts for half the planet’s mass. The sleuthing scientists wondered whether the missing xenon could be squirreled away in pockets in this mineral. The researchers tried dissolving xenon and argon in perovskite at temperatures exceeding 1,600 ºC and pressures about 250 times those at sea level. Under these extreme conditions — similar to those in the lower mantle — the mineral sopped up argon yet found little room for xenon.

 

Those results may sound disappointing, but what if xenon isn’t hiding at all? More than 4 billion years ago, Earth was molten. Meteorites bombarded the planet, causing it to lose much of its primordial atmosphere. Argon and the other noble gases hid in perovskite, but most of the xenon could not dissolve in the mineral, and disappeared into space. As further support for this hypothesis, scientists point out that the relative ratios of three noble gases — xenon, krypton and argon — in the atmosphere roughly correspond to their solubility in perovskite.

 

However, any explanation for Earth’s missing xenon should also apply to Mars, where the atmosphere also has a dearth of the noble gas xenon. Perhaps there too, the ancient xenon escaped into space: the planet’s puny gravitational field prevented it from holding onto the gas. As a result, all xenon currently found on Mars is what little could dissolve in perovskite.

 

However, Mars has not enough (if any) perovskite to explain the xenon in its atmosphere. Until the mystery of missing Martian xenon is solved, the jury is still out on where Earth’s xenon really went.

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History Of Life On Earth Shown As A 24 Hour Clock

History Of Life On Earth Shown As A 24 Hour Clock | Amazing Science | Scoop.it

For decades the origin and evolution of life was restricted to the fossil record that recorded hard-shelled life. We now know, through determination of absolute ages by radioactive decay, that this record only record the last 500 m.y. or so of life. Prior to that, life existed as soft-bodied organisms, or even earlier, as single cell bacteria (prokaryotes) or single-celled organisms with nuclei (eukaryotes). The oldest microfossils, composed of single-celled organisms that probably were similar to cyanobacteria, are 3.5 b.y. old, and are found in Western Australia (not the same locality where the very old zircon mineral grains were found). More convincing evidence for life in the Archean comes from fossil layered microbial communities called stromatolites. Although the 3.5 b.y. old microfossils are still debated, people pretty much agree that the fossil record for life is undisputable by about 3.0 b.y., and stromatolites are part of this evidence. Fossil bacteria are universally accepted for the Proterozoic, where the images (and chemical compositions) are much more clear than the fuzzy images for the 3.5 b.y. old microfossils.

 

The Proterozoic microfossils are much more similar to the modern cyanobacteria. The occurrence of cyanobacteria early in earth's history is critical, since their metabolic "waste product" is oxygen, and it was essential to produce high levels of oxygen in the earth's atmosphere before more complex life (which requires different means of metabolism and energy storage) could evolve. In the latest part of the Proterozoic (~ 600 m.y. ago), multi-cellular, complex life is recorded in the fossil record.

 

The figure shown above casts the origin and evolution of life into a 24 hour clock.

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DNA from male fetuses can remain in mothers’ brains for a lifetime

DNA from male fetuses can remain in mothers’ brains for a lifetime | Amazing Science | Scoop.it

Bearing sons can alter your mind. Giving a whole new meaning to "pregnancy brain," a new study shows that male DNA—likely left over from pregnancy with a male fetus—can persist in a woman's brain throughout her life. Although the biological impact of this foreign DNA is unclear, the study also found that women with more male DNA in their brains were less likely to have suffered from Alzheimer's disease—hinting that the male DNA could help protect the mothers from the disease, the researchers say.

 

During mammalian pregnancy, the mother and fetus exchange DNA and cells. Previous work has shown that fetal cells can linger in the mother's blood and bone for decades, a condition researchers call fetal microchimerism. The lingering of the fetal DNA, research suggests, may be a mixed blessing for a mom: The cells may benefit the mother's health—by promoting tissue repair and improving the immune system—but may also cause adverse effects, such as autoimmune reactions.

 

One question is how leftover fetal cells affect the brain. Researchers have shown that fetal microchimerism occurs in mouse brains, but they had not shown this in humans. So a team led by autoimmunity researcher and rheumatologist J. Lee Nelson of the Fred Hutchinson Cancer Research Center in Seattle, Washington, took samples from autopsied brains of 59 women who died between the ages of 32 and 101. By testing for a gene specific to the Y chromosome, they found evidence of male DNA in the brains of 63% of the women.

 

Because some studies have suggested that the risk of Alzheimer's disease (AD) increases with an increasing number of pregnancies, the team also examined the brains for signs of the disease, allowing them to determine whether AD correlated with the observed microchimerism. Of the 59 women, 33 had AD—but contrary to the team's expectation, the women with AD had significantly less male DNA in their brains than did the 26 women who did not have AD. Whether that correlation means that fetal male DNA helps protect women against AD is unclear, however. "To me, this suggests that the presence of fetal cells in the female brain prevents disease," says cardiologist Hina Chaudhry of Mount Sinai School of Medicine in New York City.

 

In a study published online in Circulation Research late last year, Chaudhry and colleagues found that fetal cells in mice migrated to the mother's heart, differentiated into functioning cardiac cells, and accelerated repair to damaged heart tissue. So, Chaudhry says, a similar thing could be happening when fetal cells migrate to the brain. "I would bet these cells are getting into the maternal brain and are able to differentiate into neurons."

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What Quantum Experiments Suggest About The World Around Us: The Future Influences The Present And The Past

What Quantum Experiments Suggest About The World Around Us: The Future Influences The Present And The Past | Amazing Science | Scoop.it
An amazing set of experiments suggest the present and the future are entangled, and that events in the future may influence things happening in the world now.

 

We've been taught our consciousness -− and everything else in the world -− flows like an arrow in one direction from the cradle to the grave. But an amazing set of experiments suggest the present and the future are entangled, and that events in the future may influence things happening in the world now. Since this sounds absurd, let's go straight to an actual experiment published in 2002. Scientists showed that pairs of particles could anticipate what their distant twins would do in the future. They stretched the distance one of the photons took to reach its detector, so the other photon would hit its own detector first. The photons taking this path already finished their journeys -− they either collapse into a particle or don't before their twin encounters a scrambling device. They decided this before their twin ever encountered the scrambler. Somehow, the particles "knew" what the researcher would do before it happened.

 

In a 2007 experiment, scientists shot photons into an apparatus and showed they could retroactively change whether they behaved as particles or waves. The particles had to "decide" what to do when they passed a fork in the apparatus. Later on, the experimenter could flip a switch. It turns out what the observer decided at that point determined how the particle had behaved at the fork in the past.

 

Eminent Princeton physicist John Wheeler (who coined "black hole") insisted when observing light from a distant quasar bent around a galaxy, we've set up a quantum observation on an enormously large scale. It means, he said, the measurements made on incoming light now, determines the path it took billions of years ago. This mirrors the results of the actual quantum experiment described above, where an observation now determines what a particle's twin did in the past.

 

In 2002, Discover magazine sent a reporter to the coast of Maine to speak to Wheeler firsthand. Wheeler said he was sure the universe was filled with "huge clouds of uncertainty" that haven't yet interacted either with a conscious observer or even with some lump of inanimate matter. In all these places, he said, the cosmos is "a vast arena containing realms where the past is not yet the past."

 

This logic applies not just to events that took place billions of years ago. What you do today could influence past events -- say, at the building of the Great Pyramids, the birth and death of Christ, or landing on the moon -- or events that will occur millions of years in the future when the Sun's dome obscures the heavens.

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Seeing Through the Big Bang into Another World (2012)- Professor Sir Roger Penrose

According to currently standard cosmology, the universe started with a Big Bang, immediately followed by a fleeting moment of exponential expansion, called "inflation". Following this it settled down to a more sedate expansion, but due to what is called "dark energy", it is currently commencing a second period of exponential expansion that is expected to continue indefinitely. In this talk I describe an alternative idea, which argues that this picture provides merely one aeon of a continual succession of such aeons. The Universe never collapses in this model, but the remote future of each aeon becomes, when infinitely scaled down, the big bang of the next. Collisions between supermassive black holes in the aeon previous to ours would, according to my model, provide disturbances that should be just about observable in the cosmic microwave background of our own aeon. In this talk I shall describe evidence indicating that these disturbances may actually be present, and possibly providing us with some hint of what the aeon prior to ours may actually have been like. The talk will be largely free of equations, depending mostly on pictures, but a brief summary of the equations needed for the theory will be provided at the end.

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Kinect-based system detects touch and gestures on any surface

Kinect-based system detects touch and gestures on any surface | Amazing Science | Scoop.it

People can let their fingers — and hands — do the talking with a new touch-activated system that projects onto walls and other surfaces and allows users to interact with their environment and each other. The system uses a Microsoft Kinect camera, which identifies the fingers of a person’s hand while touching any plain surface. It also recognizes hand posture and gestures, revealing individual users by their unique traits.

 

“Imagine having giant iPads everywhere, on any wall in your house or office, every kitchen counter, without using expensive technology,” said Niklas Elmqvist, an assistant professor of electrical and computer engineering at Purdue University. “You can use any surface, even a dumb physical surface like wood. You don’t need to install expensive LED displays and touch-sensitive screens.”

 

The new “extended multitouch” system allows more than one person to use a surface at the same time and also enables people to use both hands, distinguishing between the right and left hand. Research indicates the system is 98 percent accurate in determining hand posture, which is critical to recognizing gestures and carrying out commands. The technology has many possible applications, said Karthik Ramani, Purdue’s Donald W. Feddersen Professor of Mechanical Engineering.

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Sandia’s “Cooler” technology offers fundamental breakthrough in heat transfer for microelectronics

Sandia National Laboratories has developed a fundamental breakthrough in air-cooling technology.

 

Sandia National Laboratories has developed a new technology with the potential to dramatically alter the air-cooling landscape in computing and microelectronics, and lab officials are now seeking licensees in the electronics chip cooling field to license and commercialize the device.

 

The “Sandia Cooler,” also known as the “Air Bearing Heat Exchanger,” is a novel, proprietary air-cooling invention developed by Sandia researcher Jeff Koplow, who was recently selected by the National Academy of Engineering (NAE) to take part in the NAE’s 17th annual U.S. Frontiers of Engineering symposium. Koplow said the Sandia Cooler technology, which is patent-pending, will significantly reduce the energy needed to cool the processor chips in data centers and large-scale computing environments.

 

In a conventional CPU cooler, the heat transfer bottleneck is the boundary layer of “dead air” that clings to the cooling fins. With the Sandia Cooler, heat is efficiently transferred across a narrow air gap from a stationary base to a rotating structure. The normally stagnant boundary layer of air enveloping the cooling fins is subjected to a powerful centrifugal pumping effect, causing the boundary layer thickness to be reduced to ten times thinner than normal. This reduction enables a dramatic improvement in cooling performance within a much smaller package.

 

Additionally, the high speed rotation of the heat exchanger fins minimizes the problem of heat exchanger fouling. The way the redesigned cooling fins slice through the air greatly improves aerodynamic efficiency, which translates to extremely quiet operation. The Sandia Cooler’s benefits have been verified by lab researchers on a proof-of-concept prototype approximately sized to cool computer CPUs. The technology, Koplow said, also shows great potential for personal computer applications.

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Real-time Web Monitoring of Global Internet Connectivity

Real-time Web Monitoring of Global Internet Connectivity | Amazing Science | Scoop.it

Akamai monitors global Internet conditions around the clock. With this real-time data we identify the global regions with the greatest attack traffic, cities with the slowest Web connections (latency), and geographic areas with the most Web traffic (traffic density).

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Laboratories Worldwide Seek New Ways to Look Inside the Body

Laboratories Worldwide Seek New Ways to Look Inside the Body | Amazing Science | Scoop.it
A new wave of imaging technologies, driven by the falling cost of computing, is transforming the way doctors can examine patients.

 

Today a new wave of imaging technologies is again transforming the practice of medicine. They include new pathology tools to give doctors an instantaneous diagnosis, as well as inexpensive systems, often based on smartphones, that can extend advanced imaging technologies to the entire world. On the horizon is magnetic imaging technology that will combine the speed of X-ray-based computerized tomography, or CT, with the ability of M.R.I. systems to image soft tissues. The advances are being driven largely by the falling cost of computing, as well as the increasing availability of other miniaturization technologies, including nanotechnology.

 

Advances in digital imaging are also transforming conventional laboratory tools. In a lab at Columbia University Medical Center, Matthew Putman shows how software can speed the work of a human pathologist. Dr. Putman specializes in the design of advanced polymers. However, his research requires advanced imaging software, and that has led to the development of new computerized analysis tools. His nSPEC pattern recognition software can automatically scan 12 slides and generate the same results in just 15 minutes. The software can be trained to identify a wide variety of biological structures ranging from neurons in the brain to pathogens.

 

Other traditional imaging technologies are being rapidly transformed by computation. For example, similar to Dr. Contag’s research with endoscopes, the electronics corporation Philips has developed an advanced ultrasound system that is inserted through a patient’s mouth into the esophagus. Known as three-dimensional transesophageal echocardiography, or 3-D TEE, the technique produces an image of the heart from inside the patient’s rib cage, which often prevents ultrasound from capturing clear images. Computer processing of the data, which is transported by a fiber-optic cable from the sensor, creates stunning high-resolution 3-D videos of beating hearts.

 

More recently, Philips has used computation extensively in its Heart Navigator system, which provides a three-dimensional map for a cardiologist. Only recently certified in the United States by the Food and Drug Administration, it has made the implantation of replacement heart valves by catheter routine in Europe.

 

http://tinyurl.com/ahhjvab

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Floating Islands and Underwater Golf Clubhouses - What Are The Ecological Implications?

Floating Islands and Underwater Golf Clubhouses - What Are The Ecological Implications? | Amazing Science | Scoop.it

The troubled World Project in Dubai, which has been riddled with problems since the global financial crisis in 2009 including rumors that the islands are sinking, may have found salvation. Architectural firm Dutch Docklands has developed, designed and engineered a master plan for 89 floating islands, giving current World investors the opportunity to purchase a floating paradise. The solution would provide investors with an option that's more feasible and cost-effective than building on the existing land masses, whilst also incorporating several environmental benefits: "Floating islands are environmentally friendly and leave a zero footprint after its lifespan, and opens opportunities where there is a scarcity of land," Jasper Mulder, General Manager of Dutch Docklands Maldives told Gizmag. "They are the answer to urban limitations and climate change. It secures a safe and sustainable future where conventional building methods fail."

 

The 89 floating islands proposed for the Middle East includes residential and commercial floating developments with a total surface area of 220,000 square meters (almost 2.4 million sq.ft). Dutch Docklands' floating islands may be the preference for many World investors, as "serious talks are being held as we speak" said Mulder. However, the forward-thinking Dutch architects also have plans for the Maldives. A joint venture with the government of the Maldives has led to an ambitious master plan for more than 800 hectares (80 million sq.ft) of water, with floating construction currently in development.

 

The project hopes to see the completion of four individual ring-shaped floating islands, each with 72 water-villas; 43 floating private islands in an archipelago configuration; the world's first floating 18-hole golf course; and, an 800-room floating hotel. Furthermore, the floating islands will be interconnected by underwater tunnels, and the golf course will even feature an underwater clubhouse adjoining two luxury hotels.

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Joe X. Tran's curator insight, December 14, 2014 1:07 PM

China Super Buyers |

The troubled World Project in Dubai, which has been riddled with problems since the global financial crisis in 2009 including rumors that the islands are sinking, may have found salvation. Architectural firm Dutch Docklands has developed, designed and engineered a master plan for 89 floating islands, giving current World investors the opportunity to purchase a floating paradise. The solution would provide investors with an option that's more feasible and cost-effective than building on the existing land masses, whilst also incorporating several environmental benefits.

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Carbon-containing exoplanet slightly bigger than Earth discovered around a sun-like star

Carbon-containing exoplanet slightly bigger than Earth discovered around a sun-like star | Amazing Science | Scoop.it

Orbiting a star that is visible to the naked eye, astronomers have discovered a planet twice the size of our own made largely out of diamond. The rocky planet, called '55 Cancri e', orbits a sun-like star in the constellation of Cancer and is moving so fast that a year there lasts a mere 18 hours. Cancri e is about 40 light years, or 230 trillion miles away from Earth.

 

Discovered by a U.S.-Franco research team, its radius is twice that of Earth's but it is much more dense with a mass eight times greater. It is also incredibly hot, with temperatures on its surface reaching 3,900 degrees Fahrenheit (1,648 Celsius).

 

"The surface of this planet is likely covered in graphite and diamond rather than water and granite," said Nikku Madhusudhan, the Yale researcher whose findings are due to be published in the journal Astrophysical Journal Letters.

 

The study - with Olivier Mousis at the Institut de Recherche en Astrophysique et Planetologie in Toulose, France - estimates that at least a third of the planet's mass, the equivalent of about three Earth masses, could be diamond. Diamond planets have been spotted before but this is the first time one has been seen orbiting a sun-like star and studied in such detail.

 

"This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth," Madhusudhan said, adding that the discovery of the carbon-rich planet meant distant rocky planets could no longer be assumed to have chemical constituents, interiors, atmospheres, or biologies similar to Earth. David Spergel, an astronomer at Princeton University, said it was relatively simple to work out the basic structure and history of a star once you know its mass and age.

 

"Planets are much more complex. This 'diamond-rich super-Earth' is likely just one example of the rich sets of discoveries that await us as we begin to explore planets around nearby stars."

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Fossil traces dog domestication back 33,000 years

Fossil traces dog domestication back 33,000 years | Amazing Science | Scoop.it

The bond between man and dog has always been extremely evident, an unconditioned friendship, at least from the dog’s part, which has lead the latter to be rightfully often referred to as man’s best friend. But how, why, and when did dogs become such a significant part of our lives. By domesticating farm animals like cattle, pigs or sheep, man has come a long way in sustaining himself, and one can assert that both animal domestication and farming played a major role in man’s socio-cultural and psychological evolution. But dogs? While some parts of the world today consume dog meat, and it’s been proven that some North American cultures devised clothing from fabric made out of dog hair, it’s rather safe to say that dogs weren’t domesticated with a practical goal in mind. Man’s ubiquitous need for company might have been the cause for the first domestication attempts, and one of the first such acts might have taken place in the freezing solitude of a cave in the middle of the last ice age.


Recently, scientists have come across a 33,000 year old dog fossil in Siberia, that bears the oldest signs of domestication by man so far found. A similar find was found in Belgium, when a dog fossil from the same period was discovered. When correlating the two, it seems that dog domestication didn’t result from a single event that than sparked a cultural phenomenon, but rather that it came naturally for man to befriend canines, as these isolated fossils suggest.

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Sucking CO2 from the skies with artificial trees

Sucking CO2 from the skies with artificial trees | Amazing Science | Scoop.it
Scientists are looking at ways to lower the global temperature by removing greenhouse gases from the air. Could super-absorbent fake leaves be the answer?

 

It may be a colorless, odorless and completely natural gas, but carbon dioxide is beginning to cause us a lot of problems. It only makes up a tiny fraction of the atmosphere (0.04% of all the gas by volume – or 395 parts per million) but it has a huge effect on the Earth’s temperature. That's because unlike nitrogen or oxygen, carbon dioxide molecules absorb the Sun's heat rays even though they let light rays pass through, like a greenhouse.

 

Scientists are looking at ways to modulate the global temperature by removing some of this carbon dioxide from the air. If it works, it would be one of the few ways of geo-engineering the planet with multiple benefits, beyond simply cooling the atmosphere. Every time we breathe out, we emit carbon dioxide just like all other metabolic life forms. Meanwhile, photosynthetic organisms like plants and algae take in carbon dioxide and emit oxygen. This balance has kept the planet at a comfortably warm average temperature of 14˚C (57˚F), compared with a chilly -18˚C (0˚F) if there were no carbon dioxide in the atmosphere.

 

In the Anthropocene (the Age of Man), we have shifted this balance by releasing more carbon dioxide than plants can absorb. Since the industrial revolution, humans have been burning increasing amounts of fossil fuels, releasing stored carbon from millions of years ago. Eventually the atmosphere will reach a new balance at a hotter temperature as a result of the additional carbon dioxide, but getting there is going to be difficult.

 

The carbon dioxide we are releasing is changing the climate, the wind and precipitation patterns, acidifying the oceans, warming the habitats for plants and animals, melting glaciers and ice sheets, increasing the frequency of wildfires and raising sea levels. And we are doing this at such a rapid pace that animals and plants may not have time to evolve to the new conditions. Humans won't have to rely on evolution, but we will have to spend hundreds of billions of dollars on adapting or moving our cities and other infrastructure, and finding ways to grow our food crops under these unfamiliar conditions. Even if we stopped burning fossil fuels today, there is enough carbon dioxide in the atmosphere that temperatures will continue to rise for a few hundred years. We won't stop emitting carbon dioxide today, of course, and it is now very likely that within the lifetime of people born today we will increase the temperature of the planet by at least 3˚C more than the average temperature before the industrial revolution.

 

The problem with removing carbon dioxide from the atmosphere is that it’s present at such a low concentration. In a power plant chimney, for instance, carbon dioxide is present at concentrations of 4-12% within a relatively small amount of exhaust air. Removing the gas takes a lot of energy, so it is expensive, but it’s feasible. To extract the 0.04% of carbon dioxide in the atmosphere would require enormous volumes of air to be processed. As a result, most scientists have baulked at the idea.

 

Klaus Lackner, director of the Lenfest Center for Sustainable Energy at Columbia University, has come up with a technique that he thinks could solve the problem - Fake plastic trees. Lackner has designed an artificial tree that passively soaks up carbon dioxide from the air using “leaves” that are 1,000 times more efficient than true leaves that use photosynthesis. "We don't need to expose the leaves to sunlight for photosynthesis like a real tree does," Lackner explains. "So our leaves can be much more closely spaced and overlapped – even configured in a honeycomb formation to make them more efficient."

 

The leaves look like sheets of papery plastic and are coated in a resin that contains sodium carbonate, which pulls carbon dioxide out of the air and stores it as a bicarbonate (baking soda) on the leaf. To remove the carbon dioxide, the leaves are rinsed in water vapour and can dry naturally in the wind, soaking up more carbon dioxide.

Lackner calculates that his tree can remove one tonne of carbon dioxide a day. Ten million of these trees could remove 3.6 billion tonnes of carbon dioxide a year – equivalent to about 10% of our global annual carbon dioxide emissions. "Our total emissions could be removed with 100 million trees," he says, "whereas we would need 1,000 times that in real trees to have the same effect."

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Hot Exomoons should be easier to image than Exoplanets and may give us first glimpses of foreign Exoworlds

Hot Exomoons should be easier to image than Exoplanets and may give us first glimpses of foreign Exoworlds | Amazing Science | Scoop.it

Moons, rather than planets, could star in the first images of foreign worlds outside our solar system. Once taken, such images would offer unprecedented clues to the moons' ability to support life by providing the chemical signatures carried in their light.

 

"If we can direct-image them, we can take their spectra, which means we can determine what sort of molecules are in their atmosphere," says Mary Anne Peters of Princeton University.

 

So far, more than 800 planets outside our solar system, or exoplanets, have been found using indirect methods, such as picking up the dimming of a star's light when a planet passes in front of it. But spectra from rocky planets similar in size to Earth have been tough to collect with these methods. The planetary photo album is even slimmer: only 4 systems have been imaged.

 

One challenge is that stars are bright whereas planets are dim, so a planet has to be far enough from its star to avoid being outshined. That means those worlds that have been imaged orbit outside the habitable zone, the region around a star that's warm enough for liquid water. Also, planets shining bright enough to appear in pictures must be glowing from the heat of formation and so are too young to host life.

 

But if a moon orbits a mature gas giant akin to Jupiter, the planet's gravitational pull might be constantly kneading and stretching the moon, keeping its interior molten. This process, called tidal heating, is known to fuel the furnace of Jupiter's moon Io, the most volcanically active body in our solar system. With tidal heat, an exomoon should shine in pictures. "In a sense, what we're saying is that there's a way to keep warm other than starlight," says Edwin Turner, also of Princeton. "This will let us directly image moons in planetary systems even when we can't see the planet."

 

To check this idea, Turner and Peters calculated how hot a moon would have to be for current telescopes to see it. They found that most of today's observatories – such as the Keck telescope in Hawaii or the space-based Hubble and Spitzer telescopes – should be able to take moon shots, but only if the moons are around a searing 700 °C.

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Chemistry Nobel Prize 2012 for work on G-protein-coupled receptors

Chemistry Nobel Prize 2012 for work on G-protein-coupled receptors | Amazing Science | Scoop.it

Robert Lefkowitz of the Howard Hughes Medical Institute at Duke University and his former postdoc, Brian Kobilka of Stanford University, are the recipients of this year’s Nobel Prize in Chemistry. The two researchers work on one of the most important problems in biology: How cells receive and act on information from their environment. Using a range of experimental methods—including radioactive labeling and x-ray crystallography—Kobilka and Lefkowitz have elucidated the structure and function of a class of proteins known as G protein-coupled receptors (GPCRs). GPCRs span cell membranes. When, say, a hormone molecule on the outside of a cell binds to a GPCR, the protein’s structure changes such that the part of it that protrudes into the cell’s interior becomes more attractive to G proteins. The double-binding process then sets off a chain of signaling reactions that are ultimately manifested in a response.

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Panspermia? Star Sheds a Thousand Earths of Carbon-Rich Gas

Panspermia? Star Sheds a Thousand Earths of Carbon-Rich Gas | Amazing Science | Scoop.it

Call it the stellar version of the Slim-Fast diet. A red giant star named R Sculptoris shed about 1000 Earth masses of carbon-rich material 1800 years ago over a period of just 2 centuries. Located 950 light-years away and visible through binoculars, the star is red even for a red giant because the carbon it has forged has reached the stellar surface, where it forms molecules that almost completely absorb blue and violet light. Astronomers detected the ejected gas from submillimeter radiation that its carbon monoxide molecules emit. As the star expelled the material, it created a spiral pattern, because a previously unknown stellar companion is circling around the red giant and causing it to wobble in response. (In the image shown, R Sculptoris is at center, red marks the densest gas, and the green curve is the spiral the scientists have fit to the data.) The red giant will eventually cast off its entire carbon-rich envelope, leaving behind only a small hot core, while its lost material spreads into space, ready to enrich planets that have yet to be born with the key element on which all terrestrial life is based.

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Rewriting Biology: How a handful of MIT electrical engineers pioneered synthetic biology

Rewriting Biology: How a handful of MIT electrical engineers pioneered synthetic biology | Amazing Science | Scoop.it

Why would electrical engineers spend a lot of time learning about the inner workings of cells? Knight and Rettberg, who is now a principal research engineer in MIT's Department of Biological Engineering, wanted to see whether biology is sufficiently modular—and sufficiently well understood—to let researchers design, build, and test biological systems. Might they one day be able to treat cells as living circuit boards, letting genes stand in for electrical components like resistors and capacitors? They wondered if they could ultimately redesign living cells by assembling biological "circuits" from a set of standardized "parts" (genes), just as an engineer can build circuits to control electronic devices by combining the right components. If so, they could treat biology as a manufacturing technology, programming cells to produce things they wouldn't normally make—for example, drugs, fuels, or plastics. "Biology just happens to be in the business of making more copies," Knight says. "But we can subvert that. We can use it to make just about anything."

 

This new approach, known as synthetic biology, initially aroused skepticism among biologists, recalls Ron Weiss, SM '94, PhD '01, who was a grad student of Knight's in the late 1990s. In those early days, "it was rare to find a biologist that would understand or care about what we were doing," he says. Synthetic biology goes further than genetic engineering, which usually involves adding a single gene to a cell so that it will do something it wouldn't normally do. It is also different from metabolic engineering, which uses the techniques of genetic engineering to maximize cells' production of commercially useful products, such as insulin. Assembling a given set of genes in novel ways enables synthetic biologists to accomplish highly specific and sophisticated tasks that they wouldn't be able to achieve by modifying cells one gene at a time, a process that doesn't always make it possible to control their function.

 

Now an associate professor of biological engineering, Weiss joined the MIT faculty in 2009 to launch a new synthetic-biology research initiative at MIT—the Center for Integrative Synthetic Biology. The center is slated to open this fall in Technology Square and will include Rettberg and about a dozen faculty members from departments all over MIT, including biological engineering, biology, chemical engineering, and electrical engineering and computer science. (Knight, now on leave from MIT and working at Gingko Bioworks, a synthetic-biology company he cofounded, is expected to join when he returns to the Institute as a senior research scientist in electrical engineering and computer science.)

 

One of a handful of synthetic-biology programs in the world, the new center aims to make synthetic biology as convenient as possible by integrating it with systems biology—a computational approach to figuring out the complex biological interactions that determine a system's behavior (for example, a cell's response to a particular hormone). By unraveling these systems and figuring out ways to reëngineer them, the researchers hope to advance research in biofuels and synthesis of biological molecules—and to develop new ways to treat cancer, diabetes, and other diseases.

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WIMP Wars: Astronomers and Physicists Remain Skeptical of Long-Standing Dark Matter Claim

WIMP Wars: Astronomers and Physicists Remain Skeptical of Long-Standing Dark Matter Claim | Amazing Science | Scoop.it
An Italian research group has for years trumpeted a cyclical ebb and flow in particulate activity that the researchers ascribe to dark matter.

 

The generic line on dark matter is that nobody really knows what it is because nobody has seen it. The former claim remains basically unassailable—there are many forms dark matter could take. But one research group would dispute the latter assertion. Over the past several years, the Italian DAMA (for DArk MAtter) collaboration has been making the claim that their subterranean detector has registered the signature of dark matter as Earth passes through a sea of the stuff. But despite an ever-strengthening observational case for their claim, the DAMA collaboration's finding remains a source of broad skepticism within the scientific community.

 

Dark matter provides the universe with a great deal of its total mass, so it is critical to cosmic evolution, but it is both invisible and barely interactive with normal matter, making it an incredible challenge to detect directly. So far its existence has been inferred from its gravitational effects in shaping galaxies and other large-scale structures.

 

Pierluigi Belli of the University of Rome Tor Vergata and the DAMA collaboration explained that his team's detector has measured an annual fluctuation in particulate hits that seems to fit the bill for dark matter. DAMA is a detector meant to measure changes in the ambient particle environment—including, presumably, dark matter—as Earth passes through its orbit. "The velocity of Earth in the galactic frame is different at different times of the year," Belli explained. As the sun moves steadily through its orbit around the galaxy, Earth orbits the sun in turn, and the planet's velocity either adds to or subtracts from the sun's velocity. If dark matter rings the galaxy as theory predicts, Earth should be oscillating back and forth through a sea of particles. And DAMA should be able to register a yearlong ebb-and-flow cycle in the number of dark-matter particles passing through the detector.

 

In more than a dozen years of operation, DAMA has registered a seasonal fluctuation in particle hits that agrees with what a dark matter sea should look like. As predicted, the fluctuation cycle peaks around the start of June and lasts almost exactly a year. "The results are well compatible with many dark matter scenarios," Belli said. Specifically, DAMA could be seeing a very lightweight form of the preferred candidate for dark matter, known as the weakly interacting massive particle, or WIMP. "We have positive evidence for the presence of dark matter particles at a very high confidence level," Belli said. The general criteria for announcing evidence suggestive of a new particle or physical effect is three standard deviations, or 3 sigma; the benchmark for claiming a new discovery is 5 sigma. The DAMA seasonal flux is now a roughly 9-sigma effect. But doubts of the dark-matter interpretation still loom large.

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How cancer cells break free from tumors and spread

How cancer cells break free from tumors and spread | Amazing Science | Scoop.it
New MIT study identifies adhesion molecules key to cancer’s spread through the body.

 

Although tumor metastasis causes about 90 percent of cancer deaths, the exact mechanism that allows cancer cells to spread from one part of the body to another is not well understood. One key question is how tumor cells detach from the structural elements that normally hold tissues in place, then reattach themselves in a new site.

A new study from MIT cancer researchers reveals some of the cellular adhesion molecules that are critical to this process.

 

Losing and gaining adhesion - Cells inside the human body are usually tethered to a structural support system known as the extracellular matrix, which also helps regulate cellular behavior. Proteins called integrins, located on cell surfaces, form the anchors that hold the cells in place. When cancer cells metastasize, these anchors let go.

 

In this study, the researchers compared the adhesion properties of four types of cancer cells, taken from mice genetically engineered to develop lung cancer: primary lung tumors that later metastasized, primary lung tumors that did not metastasize, metastatic tumors that migrated from the lungs to nearby lymph nodes, and metastatic tumors that travelled to more distant locations such as the liver.

 

The scientists developed technology allowing them to expose each type of cell to about 800 different pairs of molecules found in the extracellular matrix. After depositing cells onto a microscope slide in tiny spots — each containing two different extracellular matrix proteins — the researchers could measure how well cells from each tumor type bound to the protein pairs. The researchers were surprised to find that adhesion tendencies of metastatic cells from different primary tumors were much more similar to each other than to those of the primary tumor from which they originally came. One pair of extracellular matrix molecules that metastatic tumors stuck to especially well was fibronectin and galectin-3, both made of proteins that contain or bind to sugars.

 

The researchers then genetically knocked down the amount of an integrin found on the surface of the cancer cells, which they had identified as interacting with fibronectin and galectin-3. In those mice, tumor spread was reduced. Other possible therapeutic approaches include blocking binding sites on fibronectin and galectin-3 with antibodies, so tumor cells can’t latch onto them.

 

To help with efforts to develop such drugs, the research team is now trying to figure out the details of tumor cells’ interactions with galectin-3 and is developing new candidate therapeutics aimed at inhibiting those interactions.

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DNA has a 521-year half-life - genetic material lasts longer than thought

DNA has a 521-year half-life - genetic material lasts longer than thought | Amazing Science | Scoop.it
Few researchers have given credence to claims that samples of dinosaur DNA have survived to the present day, but no one knew just how long it would take for genetic material to fall apart. Now, a study of fossils found in New Zealand is laying the matter to rest — and putting paid to hopes of cloning a Tyrannosaurus rex.

 

After cell death, enzymes start to break down the bonds between the nucleotides that form the backbone of DNA, and micro-organisms speed the decay. In the long run, however, reactions with water are thought to be responsible for most bond degradation. Groundwater is almost ubiquitous, so DNA in buried bone samples should, in theory, degrade at a set rate.

 

Palaeogeneticists led by Morten Allentoft at the University of Copenhagen and Michael Bunce at Murdoch University in Perth, Australia, examined 158 DNA-containing leg bones belonging to three species of extinct giant birds called moa. The bones, which were between 600 and 8,000 years old, had been recovered from three sites within 5 kilometres of each other, with nearly identical preservation conditions including a temperature of 13.1 ºC. By comparing the specimens' ages and degrees of DNA degradation, the researchers calculated that DNA has a half-life of 521 years. That means that after 521 years, half of the bonds between nucleotides in the backbone of a sample would have broken; after another 521 years half of the remaining bonds would have gone; and so on.

 

The team predicts that even in a bone at an ideal preservation temperature of −5 ºC, effectively every bond would be destroyed after a maximum of 6.8 million years. The DNA would cease to be readable much earlier — perhaps after roughly 1.5 million years, when the remaining strands would be too short to give meaningful information.

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Life Cycle of a Star - A Journey with Chandra

Life Cycle of a Star - A Journey with Chandra | Amazing Science | Scoop.it

The life cycle of a star can follow a few different paths depending on the mass it starts out with. Really massive stars may live for only a few million years before going supernova, while low mass stars such as the Sun may take billions of years to use up their fuel and then die quietly.

 

Birth - All stars are formed when a giant cloud of gas and dust, called a molecular cloud or nebula, begins to collapse under the influence of its own gravity. This may be triggered by a collision with another molecular cloud, the shockwave from a nearby supernova, or even the collision of galaxies. As the cloud contracts, it breaks apart. An individual fragment will condense into a hot, dense sphere known as a protostarA new star is born when the protostar becomes hot enough to begin fusing hydrogen into helium. Now, the star will enter the main sequence, or adult, phaseIf a star is too low in mass to initiate nuclear fusion it will become a brown dwarf.

 

Main sequence - A star will remain in this state for most of its lifetime, fusing hydrogen to make helium and releasing energy in the process. A star may fall on different points in the main sequence depending on its mass. In general, the more massive the star the shorter its lifespan on the main sequence. Red dwarfs are small, dim stars that fuse hydrogen at a slow rate, and may remain in the main sequence for hundreds of billions of years. Medium-sized yellow dwarfs such as our Sun will be in the main sequence for several billion years. Large stars may only stay in the main sequence for a few million years.

 

Maturity - Eventually a star will run out of its hydrogen fuel, and begin fusing helium and other elements instead. At that point it will leave the main sequence phase. Low-mass (red dwarf) stars will use up all their hydrogen and collapse directly into white dwarfs. Mid-sized stars like our Sun will expand and become red giants. This happens when a star runs out of hydrogen at its core. The core will collapse and begin fusing helium while hydrogen fusion is transferred to the outer layers. This causes the star to swell to many times its original size and become cooler as the heat is distributed over a larger area. More massive stars will grow into supergiants, which are among the largest stars in the Universe. In this stage a star will maintain hydrostatic equilibrium by fusing heavier and heavier elements as the lighter ones run out. The largest stars can produce elements up to iron.

 

Death and stellar remnants - Medium-sized stars like our Sun will eventually die by shedding their outer layers as a planetary nebula. The core will collapse into a white dwarf, which will eventually cool into a black dwarf. More massive stars will die in a tremendous explosion called a supernova. This happens when a massive stars begins to fuse iron. This absorbs energy and caused the core to violently collapse while the outer layers are ejected. The extreme heat produced by supernovae is responsible for the nucleosynthesis of elements heavier than iron, up to uranium. After a supernova, the core may compress into a neutron star or a black hole. Neutron stars are much denser than white dwarfs, to the point where protons and electrons combine to form neutrons (hence the name). Black holes are denser still, so much so that they produce an extremely strong gravitational force that even light cannot escape.

 

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2012 Nobel Prize in Physics for Measuring and Manipulating Individual Quantum Systems

2012 Nobel Prize in Physics for Measuring and Manipulating Individual Quantum Systems | Amazing Science | Scoop.it

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2012 to Serge Haroche, Collège de France and Ecole Normale Supérieure, Paris, France and David J. Wineland, National Institute of Standards and Technology (NIST) and University of Colorado Boulder, CO, USA ”for ground-breaking experimental methods that enable measuring and manipulation of individual quantum systems.”

 

Quantum mechanics, the study of how matter interacts with energy at the scale of atoms, has profoundly changed how scientists view the universe. On the quantum scale, matter and energy behave in ways that seem nonsensical and radically different from the world we ordinarily experience. Once exclusively in the realm of theory and thought experiments, quantum mechanics has emerged as the foundation of new scientific investigation, with intriguing possibilities for future technology and innovation.

 

This year’s laureates opened the door to experimentation and manipulation by studying individual quantum particles without destroying them; measured and controlled quantum states, once beyond the reach of direct observation; and took the first steps toward harnessing quantum mechanics, which is already at work in highly accurate atomic clocks and may fulfill the promise of quantum computers that – rather than relying on zeros and ones – will use fuzzy quantum states to conduct calculations many times faster than the most powerful computers today.

 

“This year’s Nobel Prize in Physics shines light on two ground-breaking advances in quantum physics,” said Dr. H. Frederick Dylla, executive director and CEO, American Institute of Physics. “By measuring and manipulating both light and individual atoms, these researchers have opened the door for new investigations into the previously enigmatic and unwieldy world of quantum particles, where matter behaves in ways that are quite different from what we see in classical physics. We are beginning to harness the incredible power of quantum physics to advance technology, computers, timekeeping, cryptography, and many other innovations that have yet to be imagined.”

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