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New anatomical structure discovered in human spine using micro-CT scanning

New anatomical structure discovered in human spine using micro-CT scanning | Amazing Science | Scoop.it

Researchers at The University of California, San Francisco have confirmed the existence of double layer spinal endplates in some individuals. Spinal endplates are essential to the health of intervertebral discs, the tissue that link together the bones of the back. The second layer was found to produce a scaffolding effect that provides a structural advantage to double endplates. Double endplates are visible on MRI scans, a feature that may help lead to more individualized treatment for spinal problems like degenerative disk disease.

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Expert psychologist suggests the era of genius scientists is over

Expert psychologist suggests the era of genius scientists is over | Amazing Science | Scoop.it

Dean Keith Simonton, a psychology professor at the University of California, has published a comment piece in the journal Nature, where he argues that it's unlikely mankind will ever produce another Einstein, Newton, Darwin, etc. This is because, he says, we've already discovered all the most basic ideas that describe how the natural world works. Any new work, will involve little more than adding to our knowledge base.

Simonton's comments are likely to draw a strong reaction, both in and out of the science world. It's been the geniuses among us that have driven science forward for thousands of years, after all. If no more geniuses appear to offer an entirely new way of looking at things, how will the human race ever reach new heights? Simonton has been studying geniuses and their contributions to science for more than 30 years and has even written books on them. He also writes that he hopes he is wrong in his assessment, even as he clearly doesn't think he is. Sadly, the past several decades only offer proof. Since the time of Einstein, he says, no one has really come up with anything that would mark them as a giant in the field, to be looked up to hundreds, if not thousands of years from now. Worse perhaps, he details how the way modern science is conducted is only adding to the problem. Rather than fostering lone wolves pondering the universe in isolation, the new paradigm has researchers working together as teams, efficiently going about their way, marching towards incremental increases in knowledge. That doesn't leave much room for true insight, which is of course, a necessary ingredient for genius level discoveries.


Simonton could be wrong of course – there might yet be some person that looks at all that has been discovered and compares it with his or her own observations, and finds that what we think we know, is completely wrong, and offers evidence of something truly groundbreaking as an alternative. The study of astrophysics, for example, appears ripe for a new approach. Scientists are becoming increasingly frustrated in trying to explain why the universe is not just expanding, but is doing so at an increasing rate. Perhaps most of the theories put forth over the past half-century or so, are completely off base. Modern science can't even explain gravity, after all. Isn't it possible that there is something at work that will need the intelligence, insight and courage of an Einstein to figure out? It appears we as a species are counting on it, even as we wonder if it's even possible.

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More than 70 percent of all the the corn, soy, and cotton grown in the US is genetically modified

More than 70 percent of all the the corn, soy, and cotton grown in the US is genetically modified | Amazing Science | Scoop.it

Last year's drought took a big bite out of the two most prodigious US crops, corn and soy. But it apparently didn't slow down the spread of weeds that have developed resistance to Monsanto's herbicide Roundup (glyphosate), used on crops engineered by Monsanto to resist it. More than 70 percent of all the the corn, soy, and cotton grown in the US is now genetically modified to withstand glyphosate.

 

Back in 2011, such weeds were already spreading fast. "Monsanto's 'Superweeds' Gallop Through Midwest," declared the headline of a post I wrote then. What's the word you use when an already-galloping horse speeds up? Because that's what's happening. Let's try this: "Monsanto's 'Superweeds' Stampede Through Midwest."

 

That pretty much describes the situation last year, according to a new report from the agribusiness research consultancy Stratus. Since the 2010 growing season, the group has been polling "thousands of US farmers" across 31 states about herbicide resistance. Here's what they found in the 2012 season:

 

• Nearly half (49 percent) of all US farmers surveyed said they have glyphosate-resistant weeds on their farm in 2012, up from 34 percent of farmers in 2011.
• Resistance is still worst in the South. For example, 92 percent of growers in Georgia said they have glyphosate-resistant weeds.
• But the mid-South and Midwest states are catching up. From 2011 to 2012 the acres with resistance almost doubled in Nebraska, Iowa, and Indiana.
• It's spreading at a faster pace each year: Total resistant acres increased by 25 percent in 2011 and 51 percent in 2012.
• And the problem is getting more complicated. More and more farms have at least two resistant species on their farm. In 2010 that was just 12 percent of farms, but two short years later 27 percent had more than one.

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Parasitic fly spotted on honeybees, causes workers to abandon colonies

Parasitic fly spotted on honeybees, causes workers to abandon colonies | Amazing Science | Scoop.it

Throughout North America, honeybees are abandoning their hives. The workers are often found dead, some distance away. Meanwhile, the hives are like honeycombed Marie Celestes, with honey and pollen left uneaten, and larvae still trapped in their chambers.

 

There are many possible causes of this “colony collapse disorder” (CCD). These include various viruses, a single-celled parasite called Nosema apis, a dramatically named mite called Varroa destructor, exposure to pesticides, or a combination of all of the above. Any or all of these factors could explain why the bees die, but why do the workers abandon the hive?

 

Andrew Core from San Francisco State University has a possible answer, and a new suspect for CCD. He has shown that a parasitic fly, usually known for attacking bumblebees, also targets honeybees. The fly, Apocephalus borealis, lays up to a dozen eggs in bee workers. Its grubs eventually eat the bees from the inside-out. And the infected workers, for whatever reason, abandon their hives to die.

 

There are hundreds of species of Apocephalus flies, and they’re best known for decapitating ants from the inside. The larvae, laid within an ant, migrate to the head and devour the tissue inside. The brainless ant wanders aimlessly for weeks, before the larvae release an enzyme that dissolves the connection between the ant’s head and body. The head falls off, and adult flies emerge from it.

 

A. borealis has a similar modus operandi, but it targets bees not ants. Core discovered its penchant for honeybees by sampling workers that had been stranded in the lights of his faculty building, and other locations throughout the San Francisco Bay area. The fly was everywhere. It was parasitizing bees in three-quarters of the places that Core studied, and its DNA confirmed that the species that attacked honeybees was the same one that kills bumblebees.

 

When Core exposed honeybees to the flies in his lab, he saw the same events that befall unfortunate ants. The flies lay eggs in a bee’s body and weeks later, larvae burst out from behind the insect’s head. It’s no surprise that the infected bees, with up to 13 larvae feasting on their brains, seem a little disoriented. They walk round like zombies, pacing in circles and often unable to stand up.

 

They also abandon their hives. Core found that the dying insects literally head towards the light. Large numbers of them become stranded within bright lights. Many flying insects show a similar attraction, but the stranded bees were stock still rather than buzzing about. They would also head towards lights on cold, rainy nights when other insects seek shelter.

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Keith Wayne Brown's curator insight, February 6, 2013 8:40 AM

Can nature ever cease to amaze or to cause wonder?

ComplexInsight's curator insight, March 7, 2013 2:20 PM

Awesome catch by Robin Lott and a good article.

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Brighter, Smaller, Faster - X-ray crystallography enters its second century

Brighter, Smaller, Faster - X-ray crystallography enters its second century | Amazing Science | Scoop.it

It was just over a century ago that William Lawrence Bragg and his father, William Henry Bragg, kick-started the science of X-ray crystallography in a talk at the Cambridge Philosophical Society on November 11, 1912. Since then, thousands upon thousands of structures have been solved, from table salt and diamond to RNA polymerase and the ribosome.

 

Back in the Braggs’ time, crystals were analyzed using laboratory X-ray tubes, which are relatively weak sources of continuous, noncoherent light—that is, light that travels in all directions, like lamplight. In the 1970s, researchers started using synchrotron particle accelerators, which can shoot partially focused (i.e., relatively coherent), highly intense X-ray radiation at a crystal. According to Jianwei Miao, a professor of physics and astronomy at the University of California, Los Angeles, a synchrotron can produce at least nine orders of magnitude more photons per second than a lab X-ray source, producing higher-quality diffraction data from smaller crystals.

 

Since 2009, a select number of researchers have had another option. The Linac [linear accelerator] Coherent Light Source (LCLS) at Stanford University and the SACLA (SPring-8 Angstrom Compact Free Electron Laser) in Japan are the world’s first “hard” X-ray free-electron lasers (XFELs), capable of producing light some billion times more brilliant than that from a synchrotron, and colliding it with tiny crystals in pulses just femtoseconds long. That’s like taking all the sunlight that hits the Earth and focusing it into one square millimeter, explains Janos Hajdu, a professor of molecular biophysics at Uppsala University in Sweden. Under such intense irradiation, the sample is destroyed almost instantaneously—but not before it diffracts, producing a weak but detectable signal.

 

As X-ray intensity increased, the crystal size needed to solve a structure has decreased, from about 1 mm or more for an X-ray tube, to 100–200 μm for a synchrotron, to as small as 200 nm for an X-ray laser, says Sébastien Boutet, a staff scientist at LCLS. That’s a boon for structural biologists, because growing large crystals has been a perennial source of torment. That synchrotrons and XFELs can use smaller crystals, which are easier and faster to grow, has improved matters—but the ultimate goal is to get rid of crystals altogether: to image individual molecules, molecular complexes, or viruses. That would represent a huge advance for scientists; not all proteins crystallize, and those that do sometimes adopt conformations that are not representative of their native forms in vivo.

 

Researchers have not reached that crystal-free point yet, at least not with individual proteins, but they have made significant leaps.

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Killing silicon: Inside IBM’s carbon nanotube computer chip lab

Killing silicon: Inside IBM’s carbon nanotube computer chip lab | Amazing Science | Scoop.it

At IBM’s Watson Research Center in upstate New York, some of the world’s best physicists, chemists, and nanoengineers are trying to create the first high-density, self-assembling carbon nanotube computer chip process. In much the same way that Jack Kilby at Texas Instruments discovered the monolithic VLSI process for making silicon chips in 1958, IBM desperately wants to find the process that enables the creation of carbon nanotube chips. In the next decade — or thereabouts; the goalposts keep shifting — silicon is expected to reach a miniaturization roadblock.

 

At some point, we simply won’t be able to make silicon transistors any smaller. When this happens, there will be a few materials jostling to fill the void, most notably silicon-germanium, galium arsenide, and various forms of carbon (nanotubes, nanowires, graphene). In theory, computer chips made from carbon nanotubes are massively desirable — they would be many times faster than silicon, use less power, and can scale down to just a couple of nanometers. In practice, working with carbon nanotubes — just like graphene — is proving to be rather difficult. It’s sometimes easy to forget that we have decades of experience and billions of R&D dollars plowed into silicon; expertise with new materials won’t come easy.

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17 year GIMPS is the longest continuously-running global supercomputing project in Internet

17 year GIMPS is the longest continuously-running global supercomputing project in Internet | Amazing Science | Scoop.it

On January 25th at 23:30:26 UTC, the largest known prime number, 257,885,161-1, was discovered on Great Internet Mersenne Prime Search (GIMPS) volunteer Curtis Cooper's computer. The new prime number, 2 multiplied by itself 57,885,161 times, less one, has 17,425,170 digits.  With 360,000 CPUs peaking at 150 trillion calculations per second, 17th-year GIMPS is the longest continuously-running global "grassroots supercomputing" project in Internet history.

 

Dr. Cooper is a professor at the University of Central Missouri. This is the third record prime for Dr. Cooper and his University. Their first record prime was discovered in 2005, eclipsed by their second record in 2006. Computers at UCLA broke that record in 2008 with a 12,978,189 digit prime number. UCLA held the record until University of Central Missouri reclaimed the world record with this discovery. The new primality proof took 39 days of non-stop computing on one of the university's PCs.  Dr. Cooper and the University of Central Missouri are the largest individual contributors to the project. The discovery is eligible for a $3,000 GIMPS research discovery award.

 

To prove there were no errors in the prime discovery process, the new prime was independently verified using different programs running on different hardware. Serge Batalov ran Ernst Mayer's MLucas software on a 32-core server in 6 days (resource donated by Novarti] IT group) to verify the new prime. Jerry Hallett verified the prime using the CUDA Lucas software running on a NVidia GPU in 3.6 days. Finally, Dr. Jeff Gilchrist verified the find using the GIMPS software on an Intel i7 CPU in 4.5 days and the CUDALucas program on a NVidia GTX 560 Ti in 7.7 days.

 

GIMPS software was developed by founder, George Woltman, in Orlando, Florida. Scott Kurowski, in San Diego, California, wrote and maintains the PrimeNet system that coordinates all the GIMPS clients. Volunteers have a chance to earn research discovery awards of $3,000 or $50,000 if their computer discovers a new Mersenne prime. GIMPS' next major goal is to win the $150,000 award administered by the Electronic Frontier Foundation offered for finding a 100 million digit prime number.

 

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Are super-Earths actually mini-Neptunes?

Are super-Earths actually mini-Neptunes? | Amazing Science | Scoop.it

In the last two decades astronomers have found hundreds of planets in orbit around other stars. One type of these so-called 'exoplanets' is the super-Earths that are thought to have a high proportion of rock but at the same time are significantly bigger than our own world. Now a new study led by Helmut Lammer of the Space Research Institute (IWF) of the Austrian Academy of Sciences suggests that these planets are actually surrounded by extended hydrogen-rich envelopes and that they are unlikely to ever become Earth-like. Rather than being super-Earths, these worlds are more like mini-Neptunes.

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World's First Digital Laser Designed and Built in Africa

World's First Digital Laser Designed and Built in Africa | Amazing Science | Scoop.it

African physicists build the first laser with a beam that can be controlled and shaped digitally.

 

Physicists currently change the shape by placing various kinds of beam-shaping devices in front of the laser. These include lenses, mirrors and digital holograms generated using spatial light modulators. But because these devices are essentially bolted on to the front of a laser, they all require expensive custom optics that have to be calibrated each time they are changed.

 

Today, however, Sandile Ngcobo at the University of KwaZulu–Natal in South Africa and few buddies, say they’ve worked out a way round this. And they’ve designed and built a device to test their idea. The solution is simple. Instead of putting  a spatial light modulator in front of the laser, they’ve built one in to the device, where it acts as the mirror at one end of the cavity. In this way, the spatial light modulator shapes the beam as it is being amplified.

 

The result is that the beam is already shaped in the required way when it emerges from the laser cavity. “We have demonstrated a novel digital laser that allows arbitrary intra-cavity laser beam shaping to be executed on the fly,” say Ngcobo and co.

 

The big advantage of all this is that the spatial light modulator generates patterns electronically. That allows these guys to change the beam shape at the touch of a button and without any of the time-consuming set up required with other methods.

 

They call their device a digital laser, because the beam can be shaped electronically with a computer. That’s the first time such a machine has been built.

 

The results are interesting. In putting the digital laser though it’s paces, they’ve shown how it can produce all kinds of beams with different shapes (see figure).

 

The applications are many. It will make various kinds of technologies much simpler, such as holographic laser tweezers and controlling aberrations in real time. Impressive stuff!

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Earth: The Virus Planet -- Earth's Invisible World Would Reach Out 100-Million Light Years

Earth: The Virus Planet -- Earth's Invisible World Would Reach Out 100-Million Light Years | Amazing Science | Scoop.it

Viruses are by far the most abundant 'lifeforms' in the oceans and are the reservoir of most of the genetic diversity in the sea. The estimated 10E30 viruses in the ocean, if stretched end to end, would span farther than the nearest 60 galaxies. Every second, approximately 10E23 viral infections occur in the ocean. These infections are a major source of mortality, and cause disease in a range of organisms, from shrimp to whales. As a result, viruses influence the composition of marine communities and are a major force behind biogeochemical cycles. Each infection has the potential to introduce new genetic information into an organism or progeny virus, thereby driving the evolution of both host and viral assemblages. Probing this vast reservoir of genetic and biological diversity continues to yield exciting discoveries.

 

Over tens, hundreds and millions years, our ancestors have been picking up retroviruses (HIV is a retrovirus) that reproduce by taking their genetic material and inserting it into our own chromosomes. There are probably about 100,000 elements in the human genome that you can trace to a virus ancestor. They make up about 8 percent of our genome, and genes that encode proteins only make up 1.2 percent of our genome making us more virus than human.

 

Occasionally, a retrovirus will end up in a sperm cell or an egg and insert its genes there, which then may give rise to a new organism, a new animal, a new person where every cell in that body has got that virus.

 

Nature: http://tinyurl.com/abmjhtf

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Scientists use Amazon Cloud to view molecular machinery in remarkable detail

Scientists use Amazon Cloud to view molecular machinery in remarkable detail | Amazing Science | Scoop.it

Salk researchers share a how-to secret for biologists: code for Amazon Cloud that significantly reduces the time necessary to process data-intensive microscopic images

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The method promises to speed research into the underlying causes of disease by making single-molecule microscopy of practical use for more laboratories.

 

"This is an extremely cost-effective way for labs to process super-resolution images," says Hu Cang, Salk assistant professor in the Waitt Advanced Biophotonics Center and coauthor of the paper. "Depending on the size of the data set, it can save over a week's worth of time."

 

The latest frontier in basic biomedical research is to better understand the "molecular machines" called proteins and enzymes. Determining how they interact is key to discovering cures for diseases. Simply put, finding new therapies is akin to troubleshooting a broken mechanical assembly line-if you know all the steps in the manufacturing process, it's much easier to identify the step where something went wrong. In the case of human cells, some of the parts of the assembly line can be as small as single molecules.

 

According to the Abbe limit, it is impossible to see the difference between any two objects if they are smaller than half the wavelength of the imaging light. Since the shortest wavelength we can see is around 400 nanometers (nm), that means anything 200 nm or below appears as a blurry spot. The challenge for biologists is that the molecules they want to see are often only a few tens of nanometers in size.

 

"You have no idea how many single molecules are distributed within that blurry spot, so essential features and ideas remain obscure to you," says Jennifer Lippincott-Schwartz, a Salk non-resident fellow and coauthor on the paper.

 

In the early 2000s, several techniques were developed to break through the Abbe Limit, launching the new field of super-resolution microscopy. Among them was a method developed by Lippincott-Schwartz and her colleagues called Photoactivated Localization Microscopy, or PALM.

 

PALM, and its sister techniques, work because mathematics can see what the eye cannot: within the blurry spot, there are concentrations of photons that form bright peaks, which represent single molecules. The downside to these approaches is that it can take several hours to several days to crunch all the numbers required just to produce one usable image.

 

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Increase in Deadly Rains Linked to Climate Change, Study Finds

Increase in Deadly Rains Linked to Climate Change, Study Finds | Amazing Science | Scoop.it

Recent extreme rains may have been intensified by the rising global average temperature.

 

Don’t let the drought in the U.S. fool you, intense rainfall around the world has been causing deadly floods in the past few years. Several have died in the current flooding in Queensland, Australia. In July 2012, the heaviest rain in decades left 37 dead in Beijing, China. More than 400 Pakistanis died in floods in September 2012. The now shriveled Mississippi River was a raging flood in 2011, killing 24 Americans in associated flash floods.

 

Recent extreme rains may have been intensified by the rising global average temperature, according to a recent study, which examined data from more than 8,000 weather stations around the planet. The study looked for correlations between atmospheric temperature and extreme rainfall between 1900 to 2009.

 

“The results are that rainfall extremes are increasing on average globally,” lead author Seth Westra of the University of Adelaide said in a press release. “They show that there is a 7% increase in extreme rainfall intensity for every degree increase in global atmospheric temperature.

 

“If extreme rainfall events continue to intensify, we can expect to see floods occurring more frequently around the world.

 

“Assuming an increase in global average temperature by 3 to 5 degrees Celsius by the end of the 21st century, this could mean very substantial increases in rainfall intensity as a result of climate change,” Westra said.

The majority of weather stations showed an increase in rainfall. The largest increase in rainfall occurred in tropical nations.

 

“Most of these tropical countries are very poor and thus not well placed to adapt to the increased risk of flooding, which puts them in a larger threat of devastation,” said Westra.

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Computer model indicates promising new catalyst for generating hydrogen from water

Computer model indicates promising new catalyst for generating hydrogen from water | Amazing Science | Scoop.it
Research conducted at Princeton and Rutgers Universities offers hope of synthetic catalysts that could produce hydrogen from water more efficiently.

 

Hydrogen is often hailed as a promising environmentally-friendly fuel source, but it is also relatively expensive to produce. However, new research conducted at Princeton University and Rutgers University poses the opportunity to produce hydrogen from water at a lower cost and more efficiently than previously thought possible.

 

The research, led by Princeton chemistry professor Annabella Selloni, takes its inspiration from nature – or more specifically, a bacteria that produces hydrogen from water by using enzymes known as di-iron hydro­ge­nases. Selloni and her fellow scientists made use of a computer model to work out how they could incorporate this function of the enzymes into practical synthetic catalysts, in order to enable humans to produce hydrogen from water.

 

In a paper published in the Proceedings of the National Academy of Sciences of the United States of America, Selloni and her co-authors detail how they made changes to existing water-to-hydrogen catalysts, which are often blighted by a susceptibility to oxygen poisoning. While aiming to improve the stability of the structure in water, the team happily fell upon a catalyst which also appears to be tolerant to oxygen, and without sacrificing efficiency.

 

The new artificial catalyst could be produced from abundant and inexpensive components like iron, offering a potentially cheap method of producing hydrogen.

 

The next step for Selloni and her team is to move the research beyond computer models into the real world, and to this end, they hope to eventually produce a working catalyst which produces vast quantities of inexpensive hydrogen for use as a fuel source.

 
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Human hearing beats the Fourier uncertainty principle 10 fold

Human hearing beats the Fourier uncertainty principle 10 fold | Amazing Science | Scoop.it

For the first time, physicists have found that humans can discriminate a sound's frequency (related to a note's pitch) and timing (whether a note comes before or after another note) more than 10 times better than the limit imposed by the Fourier uncertainty principle. Not surprisingly, some of the subjects with the best listening precision were musicians, but even non-musicians could exceed the uncertainty limit. The results rule out the majority of auditory processing brain algorithms that have been proposed, since only a few models can match this impressive human performance.

 

By ruling out many of the simpler models of auditory processing, the new results may help guide researchers to identify the true mechanism that underlies human auditory hyperacuity. Understanding this mechanism could have wide-ranging applications in areas such as speech recognition; sound analysis and processing; and radar, sonar, and radio astronomy.


"You could use fancier methods in radar or sonar to try to analyze details beyond uncertainty, since you control the pinging waveform; in fact, bats do," Magnasco said. Building on the current results, the researchers are now investigating how human hearing is more finely tuned toward natural sounds, and also studying the temporal factor in hearing.


"Such increases in performance cannot occur in general without some assumptions," Magnasco said. "For instance, if you're testing accuracy vs. resolution, you need to assume all signals are well separated. We have indications that the hearing system is highly attuned to the sounds you actually hear in nature, as opposed to abstract time-series; this comes under the rubric of 'ecological theories of perception' in which you try to understand the space of natural objects being analyzed in an ecologically relevant setting, and has been hugely successful in vision. Many sounds in nature are produced by an abrupt transfer of energy followed by slow, damped decay, and hence have broken time-reversal symmetry. We just tested that subjects do much better in discriminating timing and frequency in the forward version than in the time-reversed version (manuscript submitted). Therefore the nervous system uses specific information on the physics of sound production to extract information from the sensory stream.


"We are also studying with these same methods the notion of simultaneity of sounds. If we're listening to a flute-piano piece, we will have a distinct perception if the flute 'arrives late' into a phrase and lags the piano, even though flute and piano produce extended sounds, much longer than the accuracy with which we perceive their alignment. In general, for many sounds we have a clear idea of one single 'time' associated to the sound, many times, in our minds, having to do with what action we would take to generate the sound ourselves (strike, blow, etc)."

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Caffeine Jitters: How much caffeine is too much caffeine?

Caffeine Jitters: How much caffeine is too much caffeine? | Amazing Science | Scoop.it

Sales boost in energy drinks and deaths linked to the products make scientists and regulators worry about safe levels of the stimulant.

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Nancy Rosas Delgadillo's curator insight, April 22, 2013 7:26 PM

Hoy en día las bebidas energizantes son un producto que se vende libremente en los supermercados, siendo aún para los niños de fácil acceso, ya que estos no tienen una ley que controle su venta.

 

Recordemos que estas bebidas contienen cantidades importanes de cafeína, y como ya muchos especialistas han dicho, la cafeína es una droga estimulante y adictiva, por lo que las autoridades deberían tomar cartas en el asunto.

 

Datos interesantes, profundidad correcta, tema relevante.

 

Puntuación: 10/10

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8th century gamma ray burst irradiated the Earth, study finds

8th century gamma ray burst irradiated the Earth, study finds | Amazing Science | Scoop.it

A nearby short duration gamma-ray burst may be the cause of an intense blast of high-energy radiation that hit the Earth in the 8th century, according to new research led by astronomers Valeri Hambaryan and Ralph Neuhӓuser.

 

In 2012 scientist Fusa Miyake announced the detection of high levels of the isotope Carbon-14 and Beryllium-10 in tree rings formed in 775 CE, suggesting that a burst of radiation struck the Earth in the year 774 or 775. Carbon-14 and Beryllium-10 form when radiation from space collides with nitrogen atoms, which then decay to these heavier forms of carbon and beryllium. The earlier research ruled out the nearby explosion of a massive star (a supernova) as nothing was recorded in observations at the time and no remnant has been found. Prof. Miyake also considered whether a solar flare could have been responsible, but these are not powerful enough to cause the observed excess of carbon-14. Large flares are likely to be accompanied by ejections of material from the Sun's corona, leading to vivid displays of the northern and southern lights (aurorae), but again no historical records suggest these took place. Following this announcement, researchers pointed to an entry in the Anglo-Saxon Chronicle that describes a 'red crucifix' seen after sunset and suggested this might be a supernova. But this dates from 776, too late to account for the carbon-14 data and still does not explain why no remnant has been detected. Drs. Hambaryan and Neuhӓuser have another explanation, consistent with both the carbon-14 measurements and the absence of any recorded events in the sky. They suggest that two compact stellar remnants, i.e. black holes, neutron stars or white dwarfs, collided and merged together. When this happens, some energy is released in the form of gamma rays, the most energetic part of the electromagnetic spectrum that includes visible light.

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Exosomes: The Little Vesicles That Could Be Of Great Importance To Biology

Exosomes: The Little Vesicles That Could Be Of Great Importance To Biology | Amazing Science | Scoop.it

Exosomes, also sometimes called microvesicles, are small lipid vesicles secreted by all cells. Like many dark corners of biology, the exosome field is a province of a few experts and is still largely unknown to the mainstream. But thanks to some exciting early results and a long list of potential medical applications, exosomes are beginning to move out of the shadows and into the light. Exosomes were the subject of two sessions at the annual American Association of Cancer Research (AACR)  meeting earlier this month. In January, the first-ever conference on exosomes brought together more than two hundred researchers from around the world. And now even the popular press is picking up on the applications of exosomes to RNA interference (RNAi) drug delivery and diagnostics in fields ranging from cancer to diabetes.

 

The main obstacle to realizing the tremendous potential of RNAi therapeutics is the challenge of delivery. Whether or not exosomes are actually used to transfer RNA between cells remains to be proven, but results presented at the exosome conference and recently published by a group at Oxford made the first attempt at this approach. Led by Matthew Wood, the group loaded modified exosomes with an siRNA designed to knock down the BACE1 gene implicated in Alzheimer’s Disease.  Although they used healthy mice as models, the researchers demonstrated proof-of-principle by showing reduced levels of BACE1 in the brain. Of course, it would be reassuring to know what exosomes actually do in the body before injecting them into patients, especially given that exosome-based drugs would be complex biologics composed of several different proteins, not just lipid vesicles. As we learn more about the biology of exosomes, however, I could imagine scientists designing exosome-mimicking particles with the minimum necessary components to carry the RNA therapeutic to its designated site in the body.

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Mystery of Dragon Curves, Fractals and the Jurassic Park

Thanks to Matthew Ward and Faraz Barzideh who helped Brady out with some curves!

The book Jurassic Park is by the late Michael Crichton.

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Research suggests meerkat predator-scanning behavior is altruistic

In order to spot potential predators, adult meerkats often climb to a higher vantage point or stand on their hind legs. If a predator is detected, they use several different alarm calls to warn the rest of the group. New Cambridge research shows that they are more likely to exhibit this behaviour when there are young pups present, suggesting that the predator-scanning behavior is for the benefit of the group rather than the individual.

 

Meerkats are a cooperatively breeding species, with a dominant breeding pair and up to 40 ‘helpers’ of both sexes who do not normally breed but instead assist with a number of cooperative activities such as babysitting and feeding of offspring.

 

However, scientists have questioned whether sentinel behaviour, when helper meerkats climb to a high point to scan for predators, and other vigilance behaviour, such as standing on their hind legs, is done for their own preservation (with the group’s increased safety being an indirect consequence) or if the primary goal is altruistic, with the main purpose being the protection of the group.

 

Peter Santema, a PhD student at the University of Cambridge’s Department of Zoology, said: “You see similar behavior in a range of mammal and bird species, and we know from previous work that other group members are less likely to be attacked by predators when someone is on guard. Biologists have been debating, however, whether the protection that other group members enjoy is just a side-effect or one of the reasons why individuals perform these guarding behaviors.”

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Last Neanderthal population existed in Southern Spain as recently as 35,000 years ago

Last Neanderthal population existed in Southern Spain as recently as 35,000 years ago | Amazing Science | Scoop.it

Scientists using a "more reliable" form of radiocarbon dating have re-assessed fossils from the region and found them to be far older than anyone thought. The work appears in the journal PNAS.

 

Its results have implications for when and where we - modern humans - might have co-existed with our evolutionary "cousins", the Neanderthals.

 

"The picture emerging is of an overlapping period [in Europe] that could be of the order of perhaps 3,000-4,000 years - a period over which we have a mosaic of modern humans being present and then Neanderthals slowly ebbing away, and finally becoming extinct," explained co-author Prof Thomas Higham from the Oxford Radiocarbon Accelerator Unit at the University of Oxford, UK.

 

"What our research contributes is that in southern Spain, Neanderthals don't hang on for another 4,000 years compared with the rest of Europe. And the hunch must be that they go extinct in the south of Spain at the same time as everywhere else," he told BBC News.

 

Though once thought to have been our ancestors, the Neanderthals are now considered an evolutionary dead end.

 

They first appear in the fossil record hundreds of thousand of years ago and, at their peak, dominated a wide range, spanning Britain and Iberia in the west to Israel in the south and Uzbekistan in the east. Our own species, Homo sapiens, evolved in Africa, and displaced the Neanderthals after entering Europe somewhere around the 45,000-year mark.

 

No-one can say for sure what, if any, active role modern humans had in the decline of Europe's Neanderthals.

 

What is clear though is that some mixing must have occurred somewhere at some point. This is evident from DNA studies that prove Neanderthals made a small but significant contribution to the genetics of many modern humans.

However, scientists think this interbreeding could have occurred outside Europe, in the eastern Mediterranean or Middle East region (the area archaeologists call the "Levant"), and quite probably even deeper in time - some 80,000-90,000 years or so ago.

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NEC and Corning achieve petabit optical transmission

NEC and Corning achieve petabit optical transmission | Amazing Science | Scoop.it

Novel multicore fiber design enables 10E15 bits per second.

 

Optical communications and IT services provider NEC Corp. of America and fiber developerCorning Inc., have announced what they are calling “record-breaking results in transmission capacity over optical fibers”.

 

The result was first reported at the OSA’s Frontiers in Optics/Laser Science XXVIII (FiO/LS) meeting, held in October 2012.

 

The partners commented, “As the foundation of telecommunications networks, optical fiber innovation enables carriers to cost effectively keep up with ever-growing traffic demands.”

 

Researchers from the NEC Labs in Princeton, NJ, USA, and from Corning’s Sullivan Park Research Center in Corning, NY, successfully demonstrated ultra-high speed transmission with a capacity of 1.05 petabit/s (1015 bits per second) over novel multi-core fiber that contains 12 single-mode and two few-mode cores by employing the advanced space division multiplexing scheme and optical multiple-input multiple-output signal processing technique.

 
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Flow cytometry for five bucks and a cell phone

Flow cytometry for five bucks and a cell phone | Amazing Science | Scoop.it

Flow cytometry, a technique for counting and examining cells, bacteria and other microscopic particles, is used routinely in diagnosing disorders, infections and cancers and evaluating the progression of HIV and AIDS. But flow cytometers are big, bulky contraptions that cost tens of thousands of dollars, making them less than ideal for health care in the field or other settings where resources are limited.


Now imagine you could achieve the same results using a device that weighs about half an ounce and costs less than five dollars. Researchers at the BioPhotonics Laboratory at the UCLA Henry Samueli School of Engineering and Applied Science have developed a compact, lightweight and cost-effective optofluidic platform that integrates imaging cytometry and florescent microscopy and can be attached to a cell phone. The resulting device can be used to rapidly image bodily fluids for cell counts or cell analysis.


The research, which was led by Aydogan Ozcan, a professor of electrical engineering and bioengineering and a member of the California NanoSystems Institute at UCLA, is currently available online in the journal Analytical Chemistry. "In this work, we developed a cell phone–based imaging cytometry device with a very simple optical design, which is very cost-effective and easy to operate," said Hongying Zhu, a UCLA Engineering postdoctoral scholar at the BioPhotonics Lab and co-author of the research.


"It has great potential to be used in resource-limited regions to help people there improve the quality of their health care." The device is the latest advance by Ozcan's research team, which has developed a number of innovative, scaled-down, cell phone–based technologies that have the potential to transform global health care. "We have more than 5 billion cell phone subscribers around the world today, and because of this, cell phones can now play a central role in telemedicine applications," Ozcan said. "Our research group has already created a very nice set of tools, including cell phone microscopes, that can potentially replace most of the advanced instruments used currently in laboratories."

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Potential for Life in the Universe --Is It Reaching its Peak?

Potential for Life in the Universe --Is It Reaching its Peak? | Amazing Science | Scoop.it

The Universe is passing through the stelliferous era --its peak of star formation--but appears to be still peaking in its formation of planets, according to Dimitar Sasselov, Professor of Astronomy at Harvard University and director of the Harvard Origins of Life Initiative. There are more stars in the Universe than there are grains of sand on Earth and there are an equal number of planets.

 

There are 200 billion stars in the Milky Way and 90% are small enough and old enough to have planets in orbit. And only 10% of these stars were formed with enough heavy elements to have Earth-like planets with 2% of these --or 100 million super-Earths and Earths-- will orbit within their star's habitable zone.

 

Differing from Sasselov, an important study by an international team of astronomers has established that the rate of formation of new stars in the Universe is now only 1/30th of its peak and that this decline is only set to continue.

 

The accepted model for the evolution of the Universe predicts that stars began to form about 13.4 billion years ago, or around three hundred million years after the Big Bang. Many of these first stars are thought to have been monsters by today's standards, and were probably hundreds of times more massive than our Sun. Such beasts aged very quickly, exhausted their fuel, and exploded as supernovae within a million years or so. Lower mass stars in contrast have much longer lives and last for billions of years. Much of the dust and gas from stellar explosions was (and is still) recycled to form newer and newer generations of stars.

 

Our Sun, for example, is thought to be a third generation star, and has a very typical mass by today's standards. But regardless of their mass and properties, stars are key ingredients of galaxies like our own Milky Way. Unveiling the history of star formation across cosmic time is fundamental to understanding how galaxies form and evolve. Enlarge This diagram indicates the changing ‘GDP’ of the Universe over time.

 

The results, reported by a team led by David Sobral of the University of Leiden in the Netherlands, are published in the journal Monthly Notices of the Royal Astronomical Society. Their findings indicate that, measured by mass, the production rate of stars has dropped by 97% since its peak 11 billion years ago.

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Researchers report first transparent paper-based transistors, which could lead to green electronics

Researchers report first transparent paper-based transistors, which could lead to green electronics | Amazing Science | Scoop.it

But to make paper-based circuits that can perform calculations or control displays, researchers need to find a way to print transistors. Unfortunately, previous paper transistors perform poorly because the surface of regular paper is bumpy and uneven. For a transistor to perform optimally, electrons have to move easily through super thin layers of conducting and semiconducting materials. These layers are only a couple hundred nanometers thick, while the bumps on the surface of regular paper are tens of micrometers tall. The paper bumps disrupt the flat layers of electronic materials and interrupt the device’s electron flow.

 

In addition to its rough surface, regular paper’s other limitation is its opaqueness. To produce electronics for transparent displays, researchers need a transparent material, like plastic or glass.

 

So for printed transistors, Liangbing Hu, a materials scientist at the University of Maryland, College Park, turned to a smooth and transparent kind of paper called nanopaper. Instead of the micrometer-sized cellulose fibers found in regular paper, sheets of this material contain nanoscale fibers that produce an even surface and allow light to pass through.

 

Hu’s group made their own nanopaper using previously reported methods, which involve treating paper pulp with oxidizing chemicals. The nanopaper has cellulose fibers with an average diameter of 10 nm. “It’s as flat as plastic,” Hu says.

 

The Maryland researchers then built transistors on the paper by depositing a layer each of three materials: first carbon nanotubes, next an insulating organic molecule, and then a semiconducting organic molecule. To complete the device, the team topped it with electrodes, also made by laying down carbon nanotubes. Besides serving as electrodes for the transistors, the nanotubes provided a structural backbone, preventing excessive wrinkling in the paper after the solvents used in the fabrication process evaporated.

The resulting transistors are about 84% transparent, and their performance decreases only slightly when bent. Still, Hu says the performance of these first transistors is not optimal. He thinks decreasing wrinkling in the nanopaper will improve the devices.

 

Jeffrey Youngblood, a materials engineer at Purdue University, calls these nanopaper-based transistors “another step down the road to renewable printed electronics.” For such devices to be practical, he says, the researchers will have to find a way to produce the transistors via a scalable process, such as roll-to-roll printing, instead of the tedious layer-by-layer process

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Restoring Vision: Zebrafish's stem cells can selectively regenerate damaged photoreceptor cells

Restoring Vision: Zebrafish's stem cells can selectively regenerate damaged photoreceptor cells | Amazing Science | Scoop.it

“For some time geneticists have known that unlike humans, stem cells in zebrafish can replace damaged cells involved in many components of eyesight. Rods and cones are the most important photoreceptors. In humans, rods provide us with night vision while cones give us a full color look at the world during the day-time,” said study leader Dr Ted Allison, who with colleagues reported the findings in the open-access journal PLoS-ONE.

 

“What was not known was whether stem cells could be instructed to only replace the cones in its retina. This could have important implications for human eyesight.”

 

“This is the first time in an animal research model that stem cells have only repaired damaged cones,” Dr Allison explained. “For people with damaged eyesight repairing the cones is most important because it would restore daytime color vision.”

 

To date almost all success in regenerating photoreceptor cells has been limited to rods not cones. Most of these previous experiments were conducted on nocturnal rodents, animals that require good night vision so they have far more rods than cones.

 

“This shows us that when cones die in a cone-rich retina, it is primarily cones that regenerate. This suggests the tissue environment provides cues to instruct stem cell how to react,” Dr Allison said.

 

This shows some hope for stem cell therapy that could regenerate damaged cones in people, especially in the cone-rich regions of the retina that provide daytime color vision.

 

The next step for the team is to identify the particular gene in zebrafish gene that activates repair of damaged cones.

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