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Guinness record: World's thinnest glass is just two atoms thick

Guinness record: World's thinnest glass is just two atoms thick | Amazing Science | Scoop.it

At just a molecule thick, it's a new record: The world's thinnest sheet of glass, a serendipitous discovery by scientists at Cornell and Germany's University of Ulm, is recorded for posterity in the Guinness Book of World Records.

 

The "pane" of glass, so impossibly thin that its individual silicon and oxygen atoms are clearly visible via electron microscopy, was identified in the lab of David A. Muller, professor of applied and engineering physics and director of the Kavli Institute at Cornell for Nanoscale Science.

 

The work that describes direct imaging of this thin glass was first published in January 2012 in Nano Letters, and the Guinness records officials took note. The record will now be published in the Guinness World Records 2014 Edition.

 

Just two atoms in thickness, the glass was an accidental discovery, Muller said. The scientists had been making graphene, a two-dimensional sheet of carbon atoms in a chicken wire crystal formation, on copper foils in a quartz furnace. They noticed some "muck" on the graphene, and upon further inspection, found it to be composed of the elements of everyday glass, silicon and oxygen.

 

They concluded that an air leak had caused the copper to react with the quartz, also made of silicon and oxygen. This produced the glass layer on the would-be pure graphene.

 

Besides its sheer novelty, Muller said, the work answers an 80-year-old question about the fundamental structure of glass. Scientists, with no way to directly see it, had struggled to understand it: it behaves like a solid, but was thought to look more like a liquid. Now, the Cornell scientists have produced a picture of individual atoms of glass, and they found that it strikingly resembles a diagram drawn in 1932 by W.H. Zachariasen – a longstanding theoretical representation of the arrangement of atoms in glass.

 

"This is the work that, when I look back at my career, I will be most proud of," Muller said. "It's the first time that anyone has been able to see the arrangement of atoms in a glass."

 

What's more, two-dimensional glass could someday find a use in transistors, by providing a defect-free, ultra-thin material that could improve the performance of processors in computers and smartphones.

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Robert Keyse's curator insight, October 23, 2013 8:43 AM

Wonderful story this..

 

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Camouflaged Octopus Uses Thousands Of Tiny Chromatophores and Reflectors To Match Surroundings

Camouflaged Octopus Uses Thousands Of Tiny Chromatophores and Reflectors To Match Surroundings | Amazing Science | Scoop.it
Roger Hanlon was following this octopus underwater and couldn't believe his eyes.

 

The ghost octopus can match the color and texture of its surroundings in fractions of a second by changing the size and shape of dynamic spots of pigments on their skin called chromatophores.

Chromatophores allow an octopus to blend in with all manner of underwater backdrops.

 

Some combination of these expandable chromatophores and reflectors underneath them allows an octopus to blend in with vegetation, rocks, or smooth surfaces almost imperceptibly. Hanlon has been studying these animals for years, and is still in awe of their camouflaging stunts. “The amazing thing is that these animals are color blind yet they are capable of creating color-match patterns,” Hanlon told Science Friday, “But we don’t know how.”

 

So, when science can’t tell us how something works, all we can do is be amazed. Watch the video again and revel in how awesome this tricky octopus is. It won’t get any more obvious, we promise. 

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Mad Scientist's curator insight, September 17, 2013 12:25 AM

This video shows the amazing the camoflague ability of the octopus. Squid and Cuttlefish (relatives of octopus) are also really good at this. What is even more amazing is that these animals are colour-blind and that their skin cells do all the work.

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Orangutans plan their travel route up to one day in advance and communicate it to other members of their clan

Orangutans plan their travel route up to one day in advance and communicate it to other members of their clan | Amazing Science | Scoop.it
Male orangutans plan their travel route up to one day in advance and communicate it to other members of their species. In order to attract females and repel male rivals, they call in the direction in which they are going to travel.

 

In order to attract females and repel male rivals, they call in the direction in which they are going to travel. Anthropologists at the University of Zurich have found that not only captive, but also wild-living orangutans make use of their planning ability.

 

For a long time it was thought that only humans had the ability to anticipate future actions, whereas animals are caught in the here and now. But in recent years, clever experiments with great apes in zoos have shown that they do remember past events and can plan for their future needs. Anthropologists at the University of Zurich have now investigated whether wild apes also have this skill, following them for several years through the dense tropical swamplands of Sumatra.

 

Orangutans generally journey through the forest alone, but they also maintain social relationships. Adult males sometimes emit loud 'long calls' to attract females and repel rivals. Their cheek pads act as a funnel for amplifying the sound in the same way as a megaphone. Females that only hear a faint call come closer in order not to lose contact. Non-dominant males on the other hand hurry in the opposite direction if they hear the call coming loud and clear in their direction.

 

"To optimize the effect of these calls, it thus would make sense for the male to call in the direction of his future whereabouts, if he already knew about them," explains Carel van Schaik. "We then actually observed that the males traveled for several hours in approximately the same direction as they had called."

 

In extreme cases, long calls made around nesting time in the evening predicted the travel direction better than random until the evening of the next day.Carel van Schaik and his team conclude that orangutans plan their route up to a day ahead. In addition, the males often announced changes in travel direction with a new, better-fitting long call. The researchers also found that in the morning, the other orangutans reacted correctly to the long call of the previous evening, even if no new long call was emitted.

 

"Our study makes it clear that wild orangutans do not simply live in the here and now, but can imagine a future and even announce their plans. In this sense, then, they have become a bit more like us," concludes Carel van Schaik.

 

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NASA: Global warming in one unmistakably compelling chart

NASA: Global warming in one unmistakably compelling chart | Amazing Science | Scoop.it

Produced by NASA, the chart illustrates how temperatures have compared to “normal” (or the 1951-1980 average) from 1880 to present, from pole to pole (-90 latitude to 90 latitude).

 

From the 1880 to the 1920s, blue and green shades dominate the chart, signaling cooler than normal temperatures in that era.  Then, from the 1930s to the 1970s, warmer yellow, oranges, and reds shades ooze in, balancing the cooler shades.

 

But since the 1970s, the blue and green shades rapidly erode and oranges and reds take over, dramatically. The rapid warming at the northern high latitudes especially jumps out in recent decades, reflecting “Arctic amplification” or more intense warming in the Arctic.  Although the warming is most pronounced up north, it is apparent at almost every latitude.

 

Of course, it is widely accepted the Earth has warmed in the last century.  Or, as the Intergovernmental Panel on Climate Change put it in 2007, the warming of the climate system is “unequivocal.”

 

But even as the debate has moved on from whether warming has occurred to the effects, there remain some doubters.  Show them this this chart – it packs an incredible amount of data into one tidy, irrefutable visual.

 

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South American Gecko found to be "unsinkable" and able to walk comfortably on water due to hydrophobicity of skin

South American Gecko found to be "unsinkable" and able to walk comfortably on water due to hydrophobicity of skin | Amazing Science | Scoop.it

At a million times smaller than a T-Rex, the tiny Brazilian pygmy gecko could easily drown in the smallest of puddles… if its skin wasn’t water repellent, that is. Incredibly it doesn’t even break the surface and can comfortably walk long stretches over water without sinking through its surface.

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Inner Ear Dysfunction Due to a Mutation of SLC12A2 Linked to Hyperactivity

Inner Ear Dysfunction Due to a Mutation of SLC12A2 Linked to Hyperactivity | Amazing Science | Scoop.it

Hyperactivity can be a frustrating experience for children as well as for their parents, teachers and other caregivers. The state typically is viewed simply as abnormal behavior, with little understanding of its causes. Now, research with mice points to an unlikely source: a defective inner ear.

 

The physiological link between hyperactivity and the inner ear lies within a mutation in a gene called Slc12a2. Normally, the gene encodes an SLC12A2 protein important in maintaining proper ionic balance and cell volume. This protein is broadly expressed in tissues, including in the central nervous system (CNS) and the inner ear.

 

The mechanism behind the biological link occurs when Slc12a2 holds a specific mutation that turns a codon (a genetic sequence) for potassium lysine into a stop codon (which terminates protein production). Researchers at Albert Einstein College of Medicine in New York City found that when this mutation took place there was a loss of detectable SLC12A2 protein. Its deficit in the inner ear resulted in a collapse of Reissner’s membrane inside the cochlea as well as additional membranes in the inner ear’s vestibular compartments (which deal with balance and spatial orientation). They were surprised to find, however, that when the mutation occurred in the genes within the particular brain regions such as the cortex, striatum (forebrain), cerebellum or throughout the CNS, neither abnormal behavior nor inner ear dysfunction resulted.

 

Michelle Antoine, then a neuroscience PhD student, suspected a physiological link when she noticed a set of mice in geneticist Jean Hébert’s lab behaving abnormally—chasing their tails and almost always moving. After analyzing the mice’s CNS and peripheral nervous systems, she found that the animal’s inner ears were defective and their brains exhibited some abnormalities. She realized the mice provided an opportunity to study the association between ear defects and abnormal behavior.

 

Hébert hopes that the finding could shift the focus of hyperactivity treatment from altering simple behavior to biology. Still, he thinks further research must be done before the gap can be bridged between treating mice and treating humans.

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Hubble spots largest known population of star clusters -- about 160,000 of them

Hubble spots largest known population of star clusters -- about 160,000 of them | Amazing Science | Scoop.it

NASA’s Hubble space telescope has discovered the largest known population of globular star clusters — an estimated 160,000 — more than two billion light years away from Earth. The galaxies are swarming like bees inside the crowded core of the giant grouping of galaxies Abell 1689. By comparison, our Milky Way galaxy hosts about 150 such clusters.

 

The Hubble observations also confirm that these compact stellar groupings can be used as reliable tracers of the amount of dark matter locked away in immense galaxy clusters. Globular clusters, dense bunches of hundreds of thousands of stars, are the homesteaders of galaxies, containing some of the oldest surviving stars in the universe.

 

An international team of astronomers, led by John Blakeslee of the National Research Council, Herzberg Astrophysics Programme at the Dominion Astrophysical Observatory in Victoria, British Columbia, Canada, discovered a bounty of these stellar fossils, which is roughly twice as large as any other population found in previous globular cluster surveys.

 

The Hubble observations also win the distance record for the farthest such systems ever studied, at 2.25 billion light-years away, researchers said.

The research team found that the globular clusters are intimately intertwined with dark matter.

 

“In our study of Abell 1689, we show how the relationship between globular clusters and dark matter depends on the distance from centre of the galaxy grouping,” said team member Karla Alamo-Martinez of the Centre for Radio Astronomy and Astrophysics of the National Autonomous University of Mexico in Morelia.

 

“In other words, if you know how many globular clusters are within a certain distance, we can give you an estimate of the amount of dark matter,” said Alamo-Martinez. The Hubble study shows that most of the globular clusters in Abell 1689 formed near the centre of the galaxy cluster, which contains a deep well of dark matter.

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Examples of quantum mechanics that can be seen in every-day life

Examples of quantum mechanics that can be seen in every-day life | Amazing Science | Scoop.it

The weird effects that show up in quantum mechanics (a lot of them anyway) are due to the wave-nature of the world making itself more apparent.  What we normally think of as “particle behavior” is just what happens when the waves you’re talking about are very small (compared to what’s around) and are “decoherent” (which means the frequency, phase and polarization are all pretty random between one photon and the next).  It’s a long way from obvious (there’s some math) but, for example, the way light streams through gaps is governed entirely by the wave-nature of light, and not because it’s a particle.

 

In addition to light’s waviness, it also has polarization (which is a fundamentally not-particle thing to have).  The polarization of light affects how it reflects off of a surface (like water) and how it scatters in a gas (like air).  If you happen to look at the sky reflecting off of a lake these effects are combined, and at one particular angle they fight each other. The amount of light that reflects off of a surface depends on the polarization of that light, which is why polarized glasses are sold to drivers to cut down on glare.  It so happens that if vertically polarized light hits water at about 37° none of it will be reflected (this is called “Brewster’s angle“).

 

Because of the way light scatters in air, if you point your hand at any point in the sky (other than the Sun), and turn your palm toward the Sun, then the flat of your hand will be aligned with the polarization of the light coming from that part of the sky.  As a result, right around dawn and dusk the entire sky is polarized in the north-south direction.

 

One consequence of this is that if you’re standing at the right angle early or late in the day, and the sky (not the Sun) is your primary light source, then the face on your digital watch can appear black.  Another is that if you look at the sky in a still lake, at about 37° from level, during dawn or dusk, while looking either north or south, you’ll find that the sky isn’t reflected at all and appears black.

 

 

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Nanomal smartphone-like malaria detection device to be field tested one year earlier than scheduled

Nanomal smartphone-like malaria detection device to be field tested one year earlier than scheduled | Amazing Science | Scoop.it

A pioneering mobile device using cutting-edge nanotechnology to rapidly detect malaria infection and drug resistance will be ready for field testing this year, one year ahead of schedule.

 

The €5.2million (£4million) Nanomal project was launched last year to provide an affordable hand-held diagnostic device to detect malaria infection and parasites’ drug resistance in 15 minutes. It will allow healthcare workers in remote rural areas to deliver effective drug treatments to counter resistance more quickly, potentially saving lives.

 

The news that the project is a year ahead of schedule comes on World Malaria Day today (25 April), as the World Health Organization warns of the alarming growth of resistance to drug treatments.

 

Nanomal lead Professor Sanjeev Krishna, from St George’s, said: “Recent research suggests there’s a real danger that current artemisinin combination therapies could eventually become obsolete, in the same way as other anti-malarials. This risk is worsened when patients presenting with a fever are given anti-malarial drugs without an analysis of the malaria parasites’ drug resistance status, or even without a diagnostic test at all, thereby reducing the treatments’ effectiveness.”

 

The Nanomal device is being developed by St George’s, University of London and Newcastle-based QuantuMDx Group. It will use a range of novel nanotechnologies to rapidly analyse the malarial DNA from a finger-prick of blood. The sample will be processed and a nanowire biosensor will detect DNA sequences of interest. This will provide a malaria diagnosis, speciation and drug resistance information in 15 minutes, allowing an effective personalised drug combination to be given immediately. The smartphone-like device will be easy to use; a healthcare worker simply puts the sample into the device, presses a few buttons and waits for the result, making it ideal for use in the field.

 

QuantuMDx’s CEO Elaine Warburton said: “Placing a full malaria screen with drug resistance status in the palm of a health professional’s hand will allow instant prescribing of the most effective anti-malaria medication for that patient. Nanomal’s rapid, low-cost test will further support the global health challenge to eradicate malaria.”

 

The device aims to provide the same quality of result as a referral laboratory, at a fraction of the time and cost. Each device could cost about the price of a smartphone initially, but may be distributed free in developing countries. A single-test cartridge will be around $13 (£10) initially, but the goal is to reduce this cost to ensure affordability in resource-limited settings.

 

In addition to improving immediate patient outcomes, the project will allow the researchers to build a better picture of levels of drug resistance in stricken areas. It will also give them information on population impacts of anti-malarial interventions. The technology could also be adapted afterwards for use with other infectious diseases.

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New connection between stacked solar cells can handle energy of 70,000 suns

New connection between stacked solar cells can handle energy of 70,000 suns | Amazing Science | Scoop.it

North Carolina State University researchers have come up with a new technique for improving the connections between stacked solar cells, which should improve the overall efficiency of solar energy devices and reduce the cost of solar energy production. The new connections can allow these cells to operate at solar concentrations of 70,000 suns worth of energy without losing much voltage as "wasted energy" or heat.

Stacked solar cells consist of several solar cells that are stacked on top of one another. Stacked cells are currently the most efficient cells on the market, converting up to 45 percent of the solar energy they absorb into electricity.

 

But to be effective, solar cell designers need to ensure the connecting junctions between these stacked cells do not absorb any of the solar energy and do not siphon off the voltage the cells produce—effectively wasting that energy as heat.

 

"We have discovered that by inserting a very thin film of gallium arsenide into the connecting junction of stacked cells we can virtually eliminate voltage loss without blocking any of the solar energy," says Dr. Salah Bedair, a professor of electrical engineering at NC State and senior author of a paper describing the work.

 

This work is important because photovoltaic energy companies are interested in using lenses to concentrate solar energy, from one sun (no lens) to 4,000 suns or more. But if the solar energy is significantly intensified—to 700 suns or more—the connecting junctions used in existing stacked cells begin losing voltage. And the more intense the solar energy, the more voltage those junctions lose—thereby reducing the conversion efficiency.

 

"Now we have created a connecting junction that loses almost no voltage, even when the stacked solar cell is exposed to 70,000 suns of solar energy," Bedair says. "And that is more than sufficient for practical purposes, since concentrating lenses are unlikely to create more than 4,000 or 5,000 suns worth of energy. This discovery means that solar cell manufacturers can now create stacked cells that can handle these high-intensity solar energies without losing voltage at the connecting junctions, thus potentially improving conversion efficiency.

 

"This should reduce overall costs for the energy industry because, rather than creating large, expensive solar cells, you can use much smaller cells that produce just as much electricity by absorbing intensified solar energy from concentrating lenses. And concentrating lenses are relatively inexpensive," Bedair says.

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Unusual Mechanism of DNA Synthesis Could Explain Certain Genetic Mutations

Unusual Mechanism of DNA Synthesis Could Explain Certain Genetic Mutations | Amazing Science | Scoop.it
Researchers have discovered how cells repair a potentially devastating kind of DNA damage.

 

The repair of chromosomal double strand breaks (DSBs) is crucial for the maintenance of genomic integrity. However, the repair of DSBs can also destabilize the genome by causing mutations and chromosomal rearrangements, the driving forces for carcinogenesis and hereditary diseases.

 

Break-induced replication (BIR) is one of the DSB repair pathways that is highly prone to genetic instability. BIR proceeds by invasion of one broken end into a homologous DNA sequence followed by replication that can copy hundreds of kilobases of DNA from a donor molecule all the way through its telomere. The resulting repaired chromosome comes at a great cost to the cell, as BIR promotes mutagenesis, loss of heterozygosity, translocations, and copy number variations, all hallmarks of carcinogenesis. BIR uses most known replication proteins to copy large portions of DNA, similar to S-phase replication. It has therefore been suggested that BIR proceeds by semiconservative replication; however, the model of a bona fide, stable replication fork contradicts the known instabilities associated with BIR such as a 1,000-fold increase in mutation rate compared to normal replication.

 

The collaborative work of graduate students working under Anna Malkova, associate professor of biology at Indiana University-Purdue University Indianapolis (IUPUI) and Kirill Lobachev, associate professor of biology at the Georgia Institute of Technology have now discovered that in budding yeast the mechanism of replication during BIR is significantly different from S-phase replication, as it proceeds via an unusual bubble-like replication fork that results in conservative inheritance of the new genetic material. They provide evidence that this atypical mode of DNA replication, dependent on Pif1 helicase, is responsible for the marked increase in BIR-associated mutations.

 

Lobachev’s lab used cutting-edge analysis techniques and equipment available at only a handful of labs around the world. This allowed the researchers to see inside yeast cells and freeze the break-induced DNA repair process at different times. They found that this mode of DNA repair doesn’t rely on the traditional replication fork — a Y-shaped region of a replicating DNA molecule — but instead uses a bubble-like structure to synthesize long stretches of missing DNA. This bubble structure copies DNA in a manner not seen before in eukaryotic cells.

 

Traditional DNA synthesis, performed during the S-phase of the cell cycle, is done in semi-conservative manner as shown by Matthew Meselson and Franklin Stahl in 1958 shortly after the discovery of the DNA structure. They found that two new double helices of DNA are produced from a single DNA double helix, with each new double helix containing one original strand of DNA and one new strand.

 

“We demonstrated that break-induced replication differs from S-phase DNA replication as it is carried out by a migrating bubble instead of a normal replication fork and leads to conservative DNA synthesis promoting highly increased mutagenesis,” Malkova said.

 

This desperation replication triggers “bursts of genetic instability” and could be a contributing factor in tumor formation. “From the point of view of the cell, the whole idea is to survive, and this is a way for them to survive a potentially lethal event, but it comes at a cost,” Lobachev said. “Potentially, it’s a textbook discovery.”

 

During break-induced replication, one broken end of DNA is paired with an identical DNA sequence on its partner chromosome. Replication that proceeds in an unusual bubble-like mode then copies hundreds of kilobases of DNA from the donor DNA through the telomere at the ends of chromosomes.

 

“Surprisingly, this is a way of synthesizing DNA in a very robust manner,” Saini said. “The synthesis can take place and cover the whole arm of the chromosome, so it’s not just some short patches of synthesis.”

 

The bubble-like mode of DNA replication can operate in non-dividing cells, which is the state of most of the body’s cells, making this kind of replication a potential route for cancer formation. “Importantly, the break-induced replication bubble has a long tail of single-stranded DNA, which promotes mutations,” Ramakrishnan said.

 

The single-stranded tail might be responsible for the high mutation-rate because it can accumulate mutations by escaping the other repair mechanisms that quickly detect and correct errors in DNA synthesis. “When it comes to cancer, other diseases and even evolution, what seems to be happening are bursts of instability, and the mechanisms promoting such bursts were unclear,” Malkova said.

 

The molecular mechanism of break-induced replication unraveled by the new study provides one explanation for the generation of mutations. We propose that the BIR mode of synthesis presents a powerful mechanism that can initiate bursts of genetic instability in eukaryotes, including humans.

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Analysis of Sutter's Mill meteorite fragments reveals organic compounds not seen before

Analysis of Sutter's Mill meteorite fragments reveals organic compounds not seen before | Amazing Science | Scoop.it
(Phys.org) —A team of researchers from Arizona State University has found that the space rock known as the Sutter's Mill meteorite had organic compounds in it that have not been found in any other known meteorite.

 

Sutter's Mill meteorite was seen streaking through the atmosphere above northern California in April 2012. That led to a search by many interested parties for the chunks that survived the intense heat and made their way to the Earth's surface—in all 77 rocks were found and turned over to scientists eager to study their composition—initial testing of some of the specimens revealed few dissoluble organic compounds. Undaunted, the researchers took another approach, applying hydrothermal treatment—a process that is meant to mimic the conditions scientists believe existed on certain parts of the Earth during the time life first emerged. This time, the team reports, the fragments released organic compounds that had never before been seen in a meteorite.

 

Organic compounds in meteorites (most of which are believed to come from the asteroid belt between Jupiter and Mars) are important to researchers who believe it's possible that life got its start here on Earth thanks to meteorites that carried payloads that added to material found on Earth. Taken together, the ingredients made for the perfect cocktail, eventually giving rise to the mysterious process that resulted in the creation of living organic matter and eventually all the forms of life that came after.

 

Looking to meteorites as a possible source for life on Earth has come about due to scientists' inability to nail down a rational explanation for the development of life based on theories of how the Earth came to exist. Of course, such theories only move the debate to another arena—if life came here from somewhere else, how did it get started in that other place? Scientists have no answer, but hope studying rocks brought from space will offer clues that may help to someday solve the puzzle.

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UCI-led Study Show Evidence That Memories Can be Created By Direct Manipulation Of The Brain

UCI-led Study Show Evidence That Memories Can be Created By Direct Manipulation Of The Brain | Amazing Science | Scoop.it
By studying how memories are made, UC Irvine neurobiologists created new, specific memories by direct manipulation of the brain, which could prove key to understanding and potentially resolving learning and memory disorders.

 

Research led by senior author Norman M. Weinberger, a research professor of neurobiology & behavior at UC Irvine, and colleagues has shown that specific memories can be made by directly altering brain cells in the cerebral cortex, which produces the predicted specific memory. The researchers say this is the first evidence that memories can be created by direct cortical manipulation.


During the research, Weinberger and colleagues played a specific tone to test rodents then stimulated the nucleus basalis deep within their brains, releasing acetylcholine (ACh), a chemical involved in memory formation. This procedure increased the number of brain cells responding to the specific tone. The following day, the scientists played many sounds to the animals and found that their respiration spiked when they recognized the particular tone, showing that specific memory content was created by brain changes directly induced during the experiment. Created memories have the same features as natural memories including long-term retention.

 

"Disorders of learning and memory are a major issue facing many people and since we've found not only a way that the brain makes memories, but how to create new memories with specific content, our hope is that our research will pave the way to prevent or resolve this global issue," said Weinberger, who is also a fellow with the Center for the Neurobiology of Learning & Memory and the Center for Hearing Research at UC Irvine.

 

The creation of new memories by directly changing the cortex is the culmination of several years of research in Weinberger's lab implicating the nucleus basalis and ACh in brain plasticity and specific memory formation. Previously, the authors had also shown that the strength of memory is controlled by the number of cells in the auditory cortex that process a sound.




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Slow-motion world for small animals - feeling for time is relative

Slow-motion world for small animals - feeling for time is relative | Amazing Science | Scoop.it

Smaller animals tend to perceive time in slow-motion, helping them to escape from larger predators, a study finds. This means that they can observe movement on a finer timescale than bigger creatures, allowing them to escape from lager predators.

 

Insects and small birds, for example, can see more information in one second than a larger animal such as an elephant. In humans, too, there is variation among individuals. Athletes, for example, can often process visual information more quickly. An experienced goalkeeper would therefore be quicker than others in observing where a ball comes from. The speed at which humans absorb visual information is also age-related. Younger people can react more quickly than older people, and this ability falls off further with increasing age.


From a human perspective, our ability to process visual information limits our ability to drive cars or fly planes any faster than we currently do in Formula 1, where these guys are pushing the limits of what is humanly possible. To go any quicker would require either computer assistance, or enhancement of our visual system, either through drugs or ultimately implants.


Some deep-sea isopods (a type of marine woodlouse) have the slowest recorded reaction of all, and can only see a light turning off and on four times per second "before they get confused and see it as being constantly on.


Having eyes that send updates to the brain at much higher frequencies than our eyes do is of no value if the brain cannot process that information equally quickly. Hence, this work highlights the impressive capabilities of even the smallest animal brains. Flies might not be deep thinkers but they can make good decisions very quickly.

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Room 8's curator insight, September 18, 2013 4:46 PM

This is a great article.

Connor Keesee's curator insight, October 9, 2013 12:22 PM

Connor Keesee Animal Science, Gold 3

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Touch the microcosmos: New haptic microscope technique allows researchers to 'feel' the microworld

Touch the microcosmos: New haptic microscope technique allows researchers to 'feel' the microworld | Amazing Science | Scoop.it
What if you could reach through a microscope to touch and feel the microscopic structures under the lens?

 

In a breakthrough that may usher in a new era in the exploration of the worlds that are a million times smaller than human beings, researchers at Université Pierre et Marie Curie in France have unveiled a new technique that allows microscope users to manipulate samples using a technology known as "haptic optical tweezers."


Featured in the journal Review of Scientific Instruments, which is produced by AIP Publishing, the new technique allows users to explore the microworld by sensing and exerting piconewton-scale forces with trapped microspheres with the haptic optical tweezers, allowing improved dexterity of micromanipulation and micro-assembly.

 

"The initial results obtained are promising and demonstrate that optical tweezers have a significant potential for haptic exploration of the microworld," said Cecile Pacoret, a co-author of the study. "Haptic optical tweezers will become an invaluable tool for force feedback micromanipulation of biological samples and nano- and microassembly parts."

 

One of the challenges in developing this technique was to sense and magnify piconewton-scale forces enough to enable human operators to perceive interactions that they have never experienced before, such as adhesion phenomena, extremely low inertia, and high frequency dynamics of extremely small objects, like the Brownian motion. The design of optical tweezers for high quality touch-based feedback is challenging, given the requirements for very high sensitivity and dynamic stability.

 

This research required a mix of different experimental techniques and theoretical knowledge. Labs at the Institut des Systèmes Intelligents et de Robotique possessed expertise in both microrobotics and in haptics which were needed but the research team, as the project progressed, realized that they needed additional expertise in optics and vision, which was available at the university. "This project would not have been possible without this multidisciplinary environment and additional collaboration of the international optical tweezers community," states Dr. Pacoret. "The high level of interdisciplinary cooperation is what made this project unique, and contributed to its success."

 

The ability to use touch as a tool to allow exploration, diagnosis and assembly of widespread types of elements from sensors, microsystems to biomedical elements, including cells, bacteria, viruses, and proteins is a real advance for laboratories. These objects are fragile, and their dimensions make them difficult to see under microscope. If this tool can restore the sense of touch under microscopic operation, it will help not only efficiency but also expand scientific creativity, said Dr. Pacoret, adding that she and her team are excited about the possibilities.

 


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Deer excrete infectious prions in their faeces

Deer excrete infectious prions in their faeces | Amazing Science | Scoop.it

Prions are transmissible, proteinaceous agents that cause fatal neurodegenerative diseases. In deer elk moose prions cause chronic wasting disease (CWD). The incidence of CWD can be remarkably high both in captive and wild herds and epidemiological data suggest that efficient horizontal transmission drives epidemic dynamics. Although deer can be infected orally and seem to be able to contract CWD from contaminated environments, precisely how and when CWD prions are shed into the environment have not been described. Previous studies have identified CWD prions in saliva, blood, urine, antler velvet, and muscle, lymphoid and other tissues of symptomatic cervids with late-stage disease. These sources of CWD prions may contribute to the spread of CWD, but none explains natural CWD transmission both within and between species in the deer family. To fit observed patterns, a natural CWD transmission mechanism must be effected within biologically realistic limits of the carrier medium, cannot require cannibalism and should be indirect to explain both environmental persistence and spread among multiple host species. Because empirical data and modelling suggested faecal excretion of prions throughout much of the disease course as potentially important to CWD transmission, researchers investigated whether prions are shed in faeces from mule deer during the course of CWD infection.


Infectious prion diseases – scrapie of sheep and chronic wasting disease (CWD) of several species in the deer family – are transmitted naturally within affected host populations. Although several possible sources of contagion have been identified in excretions and secretions from symptomatic animals, the biological importance of these sources in sustaining epidemics remains unclear. Here we show that asymptomatic CWD-infected mule deer (Odocoileus hemionus) excrete CWD prions in their faeces long before they develop clinical signs of prion disease. Intracerebral inoculation of irradiated deer faeces into transgenic mice overexpressing cervid prion protein (PrP) revealed infectivity in 14 of 15 faecal samples collected from five deer at 7–11 months before the onset of neurological disease. Although prion concentrations in deer faeces were considerably lower than in brain tissue from the same deer collected at the end of the disease, the estimated total infectious dose excreted in faeces by an infected deer over the disease course may approximate the total contained in a brain. Prolonged faecal prion excretion by infected deer provides a plausible natural mechanism that might explain the high incidence and efficient horizontal transmission of CWD within deer herds, as well as prion transmission among other susceptible cervids.


Why should we care? Apart from the impact on wildlife, vCJD is a prion infection transmitted from infected cows to humans. People eat deer. Although there is no evidence that the CWN prion causes diseae in humans, this is definitely one to keep an eye on.

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DNA Origami Nanobots vs. Cancer – It's about the Creativity of Bioengineering

DNA Origami Nanobots vs. Cancer – It's about the Creativity of Bioengineering | Amazing Science | Scoop.it

Shawn Douglas has big ideas to help fight cancer. His two roadblocks to a cure are that cancer drugs lack specificity and the cancer cells develop resistance to treatment over time. His radical solution in this Solve for X talk is to develop a new class of drugs from nanoscale devices. Inspiration comes in part from the way that penicillin fights infection. Penicillin can eat the harmful bacteria in an infection without doing harm to the host body.

 

Cancer cells, however, are close in makeup to the healthy cells that they have replaced and harder to individually target. Douglas uses animations and a gruesome graphic of a melanoma patient to explain how cancer cells can develop resistance to medicine and return stronger than original levels. To solve the specificity problem Douglas proposes a targeted delivery method that can differentiate between healthy cells and cancer cells. To solve the resistance problem he proposes combining different treatment methods to ensure all the different types of cancer cells are removed.

 

The solution to fit both sets of problems and constraints is nanoscale devices. In the lab Douglas and his team use a method codenamed DNA origami where hundreds of short DNA strands combine to create custom shapes with nanoscale precision. The devices act as a shell that delivers payload atoms to the exact cell that is targeted. Top and bottom halves are held together with strands and when signaled can open up like a clamshell, delivering the drug.

 

Extensive testing has been done in the lab to obtain a proof-of-concept level of confidence. Goals for the future include much more testing on live subjects, a method of mass production, finding new applications for nanobot delivery, and lots of new scientists. Douglas ends the talk discussing his BioMod student design competition and reminding us that bringing up the next generation of nanoscale device engineers is his most important project.

 

http://tinyurl.com/l4nel5w

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eva teruzzi's curator insight, September 22, 2013 3:37 PM

There's more than psychology in creativity!!!

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Terminator polymer: The first self-healing thermoset elastomer that requires no intervention to induce its repair

Terminator polymer: The first self-healing thermoset elastomer that requires no intervention to induce its repair | Amazing Science | Scoop.it

Self-healing polymers mend themselves by reforming broken cross-linking bonds. However, the cross-linking healing mechanism usually requires an external stimulus. Triggers to promote bond repair include energy inputs, such as heat or light, or specific environmental conditions, such as pH. Self-healing polymers that can spontaneously achieve quantitative healing in the absence of a catalyst have never been reported before, until now.

 

Ibon Odriozola previously came close when his group at the CIDETEC Centre for Electrochemical Technologies in Spain developed self-healing silicone elastomers using silver nanoparticles as cross-linkers. Unfortunately, an applied external pressure was required and the expensive sliver component disfavoured commercialisation. But now they have achieved their goal to prepare self-healing elastomers from common polymeric starting materials using a simple and inexpensive approach.

 

An industrially familiar, permanently cross-linked poly(urea–urethane) elastomeric network was demonstrated to completely mend itself after being cut in two by a razor blade. It is the metathesis reaction of aromatic disulphides, which naturally exchange at room temperature, that causes regeneration.

 

Ibon stresses the use of commercially available materials is important for industrial applications. He says the polymer behaves as if it was alive, always healing itself and has dubbed it a “terminator” polymer – a tribute to the shape-shifting, molten T-1000 terminator robot from the Terminator 2 film. It acts as a velcro-like sealant or adhesive, displaying an impressive 97% healing efficiency in just two hours and does not break when stretched manually.

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Functioning 'mechanical gears' seen in nature for the first time

Functioning 'mechanical gears' seen in nature for the first time | Amazing Science | Scoop.it

A plant-hopping insect found in gardens across Europe - has hind-leg joints with curved cog-like strips of opposing 'teeth' that intermesh, rotating like mechanical gears to synchronise the animal's legs when it launches into a jump.

 

The finding demonstrates that gear mechanisms previously thought to be solely man-made have an evolutionary precedent. Scientists say this is the "first observation of mechanical gearing in a biological structure".

 

Through a combination of anatomical analysis and high-speed video capture of normal Issus movements, scientists from the University of Cambridge have been able to reveal these functioning natural gears for the first time. The findings are reported in the latest issue of the journal Science.

 

The gears in the Issus hind-leg bear remarkable engineering resemblance to those found on every bicycle and inside every car gear-box. Each gear tooth has a rounded corner at the point it connects to the gear strip; a feature identical to man-made gears such as bike gears – essentially a shock-absorbing mechanism to stop teeth from shearing off.

 

The gear teeth on the opposing hind-legs lock together like those in a car gear-box, ensuring almost complete synchronicity in leg movement - the legs always move within 30 'microseconds' of each other, with one microsecond equal to a millionth of a second.

 

This is critical for the powerful jumps that are this insect's primary mode of transport, as even miniscule discrepancies in synchronisation between the velocities of its legs at the point of propulsion would result in "yaw rotation" - causing the Issus to spin hopelessly out of control.

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Wide range of differences, mostly unseen, among humans: Silent mutations more significant than expected

Wide range of differences, mostly unseen, among humans: Silent mutations more significant than expected | Amazing Science | Scoop.it

No two human beings are the same. Although we all possess the same genes, our genetic code varies in many places. And since genes provide the blueprint for all proteins, these variants usually result in numerous differences in protein function. But what impact does this diversity have? Bioinformatics researchers at Rutgers University and the Technische Universitaet Muenchen (TUM) have investigated how protein function is affected by changes at the DNA level. Their findings bring new clarity to the wide range of variants, many of which disturb protein function but have no discernible health effect, and highlight especially the role of rare variants in differentiating individuals from their neighbors.


The slightest changes in human DNA can result in an incorrect amino acid being incorporated into a protein. In some cases, all it takes is for a single base to be substituted in a person's DNA, a variant known as a single nucleotide polymorphism (SNP). "Many of these pointmutations have no impact on human health. However, of the roughly 10,000 'missense' SNPs in the human genome – that is, SNPs affecting the protein sequence – at least a fifth can change the function of the protein," explains Prof. Yana Bromberg of the Department of Biochemistry and Microbiology at Rutgers University. "And in some cases, the affected protein is so important and the change so large that we have to wonder why the person with this mutation is still healthy."


Furthermore, two unrelated individuals have thousands of different mutations that affect proteins. Previously, scientists did not fully understand how this large number of mutations affects the coding sequences of DNA. To investigate these "silent" mutations, Bromberg joined forces with Rutgers colleague Prof. Peter Kahn and Prof. Burkhard Rost at TUM.


"We found that many of the mutations are anything but silent," declares Rost, head of the TUM Chair for Bioinformatics and a fellow of the TUM Institute for Advanced Study. The research indicates an extremely wide range of mutations. Many SNPs, for example, are neutral and do not affect protein function. Some, however, cause pathogenic disruption to protein functionality. "There is a gray area between these extremes," Rost explains. "Some proteins have a reduced biological function but are tolerated by the organism and therefore do not directly trigger any disease."

 

The research team analyzed over one million SNPs from a number of DNA databases. They used artificial learning methods to simulate the impact of DNA mutations on the function of proteins. This approach enabled them to investigate the impact of a large number of SNPs quickly and efficiently.

 

The study's findings suggest that, with respect to diversity in protein function, the individual differences between two people are greater than previously assumed. "It seems that humans can live with many small changes in protein function," says Rost. One conclusion the researchers draw is that the wide functional spectrum of proteins must play a key role in evolution. In addition, Bromberg says, "Protein functional diversity may also hold the key to developing personalized medicine."


http://www.pnas.org/cgi/doi/10.1073/pnas.1216613110

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Rising Seas - Interactive: Explore the Coast Lines If All The Ice Melted

Rising Seas - Interactive: Explore the Coast Lines If All The Ice Melted | Amazing Science | Scoop.it

The maps here show the world as it is now, with only one difference: All the ice on land has melted and drained into the sea, raising it 216 feet and creating new shorelines for our continents and inland seas.

There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5,000 years to melt it all. If we continue adding carbon to the atmosphere, we’ll very likely create an ice-free planet, with an average temperature of perhaps 80 degrees Fahrenheit instead of the current 58.


Via Kathy Bosiak
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Amy Odlum's curator insight, September 21, 2013 4:32 PM

Year 8 Geog - Climate Change

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An extinct species of tool-making humans occupied a vast area in China as early as 1.7 million years ago

An extinct species of tool-making humans occupied a vast area in China as early as 1.7 million years ago | Amazing Science | Scoop.it
The artifacts studied may belong to Homo erectus and suggest the now-extinct human species migrated to China 700,000 years earlier than thought. Such hominid migrations to East Asia may have been due to cooling and aridity in Africa and Eurasia.

 

The human lineage evolved in Africa, with now-extinct species of humans dispersing away from their origin continent more than a million years before modern humans did. Scientists would like tolearn more about when and where humans went to better understand what drove human evolution.

 

Researchers investigated the Nihewan Basin, which lies in a mountainous region about 90 miles (150 kilometers) west of Beijing. It holds more than 60 sites from the Stone Age, with thousands of stone tools found there since 1972 — relatively simple types, such as stone flakes altogether known as the Oldowan. Researchers suspect these artifacts belonged to Homo erectus, "thought to be ancestral to Homo sapiens," Hong Ao, a paleomagnetist at the Chinese Academy of Sciences in Xi'an, told LiveScience.

 

The exact age of these sites was long uncertain. To find out, Ao and his colleagues analyzed the earth above, below and in which stone tools at the Shangshazui site in the Nihewan Basin were found. The tools in question were stone blades potentially used for cutting or scraping.

 

The scientists analyzed the way in which the samples of earth were magnetized — since the Earth's magnetic field has regularly flippednumerous times over millions of years, looking at the manner in which the magnetic fields of minerals are oriented can shed light on how old they are. The researchers discovered this site in northern China might be about 1.6 million to 1.7 million years old, making it 600,000 or 700,000 years older than previously thought.

 

Horse, elephant and other fossils suggest the area back when the stone tools were made was mainly grassland interspersed with patches of woodland. A lake between the mountains there was probably a major attraction for hominid explorers, providing water and a range of other food sources, while the mountains could have represented an important material source for making stone tools. The researchers suggest hominid migrations to East Asia during the early Stone Age were a consequence of increasing cooling and aridity in Africa and Eurasia.

 

Given that slightly older artifacts and bones belonging to Homo erectuswere previously discovered in southern China more than 1,500 miles (2,500 km) away, these new findings suggest early and now-extinct human species may potentially have occupied a huge territory in China.

 

"Homo erectus occupied a vast area in China by 1.7 million to 1.6 million years ago," Ao said.

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Made-to-order materials: Engineers focus on the nano to create strong, lightweight materials

Made-to-order materials: Engineers focus on the nano to create strong, lightweight materials | Amazing Science | Scoop.it

The lightweight skeletons of organisms such as sea sponges display a strength that far exceeds that of manmade products constructed from similar materials. Scientists have long suspected that the difference has to do with the hierarchical architecture of the biological materials—the way the silica-based skeletons are built up from different structural elements, some of which are measured on the scale of billionths of meters, or nanometers. Now engineers at the California Institute of Technology (Caltech) have mimicked such a structure by creating nanostructured, hollow ceramic scaffolds, and have found that the small building blocks, or unit cells, do indeed display remarkable strength and resistance to failure despite being more than 85 percent air.


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Scientists manage to study the physics that connect the classical the quantum world

Scientists manage to study the physics that connect the classical the quantum world | Amazing Science | Scoop.it
How does a classical temperature form in the quantum world? An experiment at the Vienna University of Technology has directly observed the emergence and the spreading of a temperature in a quantum system.

 

The connection between the microscopic world of quantum physics and our everyday experience, which is concerned with much larger objects, still remains puzzling. When a quantum system is measured, it is inevitably disturbed and some of its quantum properties are lost.

 

A cloud of atoms, for example, can be prepared in such away that each atom is simultaneously located at two different places, forming a perfect quantum superposition. As soon as the location of the atoms is measured, however, this superposition is destroyed. All that is left are atoms sitting at some well-defined places. They behave just as classical objects would.

 

In this case, the transition from quantum behavior to classical behavior is initiated by the measurement – a contact with the outside world. But what happens, if a quantum system is not influenced from the outside at all? Can classical properties still emerge?

 

"We are studying clouds consisting of several thousand atoms", explains Tim Langen, lead author of the study from Professor Jörg Schmiedmayer's research team at Vienna University of Technology. "Such a cloud is small enough to effectively isolate it from the rest of the world, but it is large enough to study how quantum properties are lost".

 

In the experiment, the atom clouds are split into two halves. After a certain time the two halves are compared to each other. In that way, the scientists can measure the amount of quantum mechanical connection between the clouds. Initially, this connection is perfect; all atoms are in a highly ordered quantum state. But as the cloud is a large object consisting of thousands of particles, this order does not remain for long.

 

As the atoms interact with each other, disorder begins to spread with a certain velocity. Atoms in the already disordered regions lose their quantum properties. A temperature can be assigned to them – just as in a classical gas. "The velocity with which the disorder spreads depends on the number of atoms", says Tim Langen. This defines a clear border between the regions which can be described by a classical temperature and regions where quantum properties remain unchanged.

 

After a certain time the disorder has spread over the whole cloud. The remarkable observation is that this loss of quantum properties happens just because of quantum effects inside the atom cloud, without any influence from the outside world. "So far, such a behavior had only been conjectured, but our experiments demonstrate that nature really behaves like this", Jörg Schmiedmayer points out.


In a way, the atomic cloud behaves like its own miniature universe. It is isolated from the environment, so its behavior is solely determined by its internal properties. Starting with a completely quantum mechanical state, the cloud looks "classical" after some time, even though it evolves according to the laws of quantum physics. That is why the experiment could not just help us to understand the behavior of large atom clouds, it could also help to explain, why the world that we experience every day looks so classical, even though it is governed by quantum laws.

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New dimensions on ice: Arctic winter ice continues to decline

New dimensions on ice: Arctic winter ice continues to decline | Amazing Science | Scoop.it
Offering new insights into our fragile polar regions, ESA’s CryoSat mission has provided three consecutive years of Arctic sea-ice thickness measurements, which show that the ice continues to thin.

 

Although satellites have witnessed a downward trend in the extent of sea ice over the last two decades, it is essential to have accurate information on the mass or volume of ice being lost. This is a more accurate measure of the changes taking place.

 

Along with observations of ice extent, CryoSat’s measurements of thickness now span from October 2010 to April 2013, allowing scientists to work out the real loss of ice, monitor seasonal change and identify trends. Prof. Andrew Shepherd from the University of Leeds, UK, said, “CryoSat continues to provide clear evidence of diminishing Arctic sea ice.

 

“From the satellite’s measurements we can see that some parts of the ice pack ice have thinned more rapidly than others, but there has been a decrease in the volume of winter and summer ice over the past three years.

“The volume of the sea ice at the end of last winter was less than 15 000 cubic km, which is lower than any other year going into summer and indicates less winter growth than usual.”

 

While it seems unlikely that a record minimum of sea-ice extent will be set this September, the thinner ice at the start of summer could mean that the actual volume of ice may reach a new low.

 

Rachel Tilling, PhD student at University College London, who is working with the CryoSat data stated, “Readings from CryoSat in October, when the ice starts to refreeze, will confirm this either way.”

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