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Accelerator on a chip: Technology could spawn new generations of smaller, cheaper devices for science, medicine

Accelerator on a chip: Technology could spawn new generations of smaller, cheaper devices for science, medicine | Amazing Science | Scoop.it

In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice. The achievement was reported today inNature by a team including scientists from the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory and Stanford University.

 

"We still have a number of challenges before this technology becomes practical for real-world use, but eventually it would substantially reduce the size and cost of future high-energy particle colliders for exploring the world of fundamental particles and forces," said Joel England, the SLAC physicist who led the experiments. "It could also help enable compact accelerators and X-ray devices for security scanning, medical therapy and imaging, and research in biology and materials science."

 

Because it employs commercial lasers and low-cost, mass-production techniques, the researchers believe it will set the stage for new generations of "tabletop" accelerators.

 

At its full potential, the new "accelerator on a chip" could match the accelerating power of SLAC's 2-mile-long linear accelerator in just 100 feet, and deliver a million more electron pulses per second.

 

This initial demonstration achieved an acceleration gradient, or amount of energy gained per length, of 300 million electronvolts per meter. That's roughly 10 times the acceleration provided by the current SLAC linear accelerator.

"Our ultimate goal for this structure is 1 billion electronvolts per meter, and we're already one-third of the way in our first experiment," said Stanford Professor Robert Byer, the principal investigator for this research.

 

Today's accelerators use microwaves to boost the energy of electrons. Researchers have been looking for more economical alternatives, and this new technique, which uses ultrafast lasers to drive the accelerator, is a leading candidate.

 

Particles are generally accelerated in two stages. First they are boosted to nearly the speed of light. Then any additional acceleration increases their energy, but not their speed; this is the challenging part.

 

In the accelerator-on-a-chip experiments, electrons are first accelerated to near light-speed in a conventional accelerator. Then they are focused into a tiny, half-micron-high channel within a fused silica glass chip just half a millimeter long. The channel had been patterned with precisely spaced nanoscale ridges. Infrared laser light shining on the pattern generates electrical fields that interact with the electrons in the channel to boost their energy.

Turning the accelerator on a chip into a full-fledged tabletop accelerator will require a more compact way to get the electrons up to speed before they enter the device.

 

A collaborating research group in Germany, led by Peter Hommelhoff at the Max Planck Institute of Quantum Optics, has been looking for such a solution. It simultaneously reports in Physical Review Letters its success in using a laser to accelerate lower-energy electrons.

 

Applications for these new particle accelerators would go well beyond particle physics research. Byer said laser accelerators could drive compact X-ray free-electron lasers, comparable to SLAC's Linac Coherent Light Source, that are all-purpose tools for a wide range of research.

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LEITNet's curator insight, October 19, 2014 4:55 PM

*Note: If we acknowledge, then set aside the technological breakthrough this technology represents, we can envision the practical applications for use in the fields of security, lawe enforcement, or the military.

 

Consider the ability of Transportation Security Officers, to quickly screen passengers, luggage and other property while the individual steps up to have their identity verified with their boarding pass/ticket information…with the need to disrobe.

 

Extend this application to the police officer conducting a traffic stop; before approaching the questioned vehicle, a quick, silent and unobtrusive scan for weapons could be conducted.

 

Finally, project this technology onto the battlefield where Soldiers, Sailors, Airmen, Marines, and Coastguard personnel are interrogating suspect facilities, individuals, and other properties for explosive threats.

 

Although the development of this technology has significant application for the medical community, the possible applications for security and law enforcement are nearly endless.

 

Dr. Eugene Matthews

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The most precise atomic clock to watch tiniest ever time dilations: Was Einstein correct?

The most precise atomic clock to watch tiniest ever time dilations: Was Einstein correct? | Amazing Science | Scoop.it

Slivers of time hundreds of trillions of times smaller than a second can now be clocked – so we can see if an object ages differently to another just below.

 

Atomic clocks have been instrumental in science and technology, leading to innovations such as global positioning, advanced communications, and tests of fundamental constant variation. Timekeeping precision at 1 part in 10E18 enables new timing applications in relativistic geodesy, enhanced Earth- and space-based navigation and telescopy, and new tests of physics beyond the standard model. Here, we describe the development and operation of two optical lattice clocks, both using spin-polarized, ultracold atomic ytterbium. A measurement comparing these systems demonstrates an unprecedented atomic clock instability of 1.6 × 10E–18 after only 7 hours of averaging.

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Is increased protein synthesis fidelity the secret weapon against aging?

Is increased protein synthesis fidelity the secret weapon against aging? | Amazing Science | Scoop.it

The naked mole-rat (Heterocephalus glaber) is a subterranean eusocial rodent with a markedly long lifespan and resistance to tumorigenesis. Multiple data implicate modulation of protein translation in longevity.

 

The 28S ribosomal RNA (rRNA) of the naked mole-rat is processed into two smaller fragments of unequal size. The two breakpoints are located in the 28S rRNA divergent region 6 and excise a fragment of 263 nt. The excised fragment is unique to the naked mole-rat rRNA and does not show homology to other genomic regions. Because this hidden break site could alter ribosome structure, scientists investigated whether translation rate and amino acid incorporation fidelity were altered. They found that naked mole-rat fibroblasts have significantly increased translational fidelity despite having comparable translation rates with mouse fibroblasts. Although they didn't directly test whether the unique 28S rRNA structure contributes to the increased fidelity of translation, they speculated that it may change the folding or dynamics of the large ribosomal subunit, altering the rate of GTP hydrolysis and/or interaction of the large subunit with tRNA during accommodation, thus affecting the fidelity of protein synthesis. These results suggest that naked mole-rat cells produce fewer aberrant proteins, supporting the hypothesis that the more stable proteome of the naked mole-rat contributes to its longevity.

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Discovery of a selective NaV1.7 inhibitor from centipede venom with analgesic efficacy exceeding morphine in rodent pain models

Discovery of a selective NaV1.7 inhibitor from centipede venom with analgesic efficacy exceeding morphine in rodent pain models | Amazing Science | Scoop.it
The Chinese red-headed centipede is one of those creepy-crawlies you might run from. But its venom appears to hold potentially powerful medicine against pain , a group of researchers in Australia and China has found.

 

The economic burden of chronic pain in the United States is currently ∼$600 billion per annum, which exceeds the combined annual cost of cancer, heart disease, and diabetes. Few drugs are available for treating chronic pain, and many have limited efficacy and dose-limiting side-effects. Humans with inheritable loss-of-function mutations in the voltage-gated sodium channel NaV1.7 are indifferent to all types of pain, and therefore drugs that block this channel should be useful analgesics for treating many pain conditions. A research team now describes Ssm6a, a peptide isolated from the centipede venom that potently and selectively blocks the human NaV1.7 channel. Ssm6a proved to be more analgesic than morphine in rodent pain models and did not cause any side-effects.

 

The identification of µ-SLPTX-Ssm6a, a unique 46-residue peptide from centipede venom, potently inhibits NaV1.7 with an IC50 of ∼25 nM. µ-SLPTX-Ssm6a has more than 150-fold selectivity for NaV1.7 over all other human NaV subtypes, with the exception of NaV1.2, for which the selectivity is 32-fold. µ-SLPTX-Ssm6a contains three disulfide bonds with a unique connectivity pattern, and it has no significant sequence homology with any previously characterized peptide or protein. µ-SLPTX-Ssm6a proved to be a more potent analgesic than morphine in a rodent model of chemical-induced pain, and it was equipotent with morphine in rodent models of thermal and acid-induced pain. This study establishes µ-SPTX-Ssm6a as a promising lead molecule for the development of novel analgesics targeting NaV1.7, which might be suitable for treating a wide range of human pain pathologies.

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Scientists Discover Third Ozone Layer in Atmosphere of Mars

Scientists Discover Third Ozone Layer in Atmosphere of Mars | Amazing Science | Scoop.it
A study in Nature Geoscience explains how atmospheric circulation creates a previously undetected ozone layer above the Red Planet's southern winter pole.

 

On our planet, ozone is a pollutant at ground level, but at higher altitudes it provides an essential protective layer against harmful solar ultraviolet light. However, ozone molecules are easily destroyed by solar ultraviolet light and by chemical reactions with hydrogen radicals, which are released by photolysis of water molecules. The role of pollution in its destruction has been a major focus of attention since the mid-1980s, when a hole in the ozone layer was discovered above Antarctica.

 

Ozone was detected on Mars in 1971. The ozone concentration on the planet is typically 300 times thinner than on Earth, although it varies greatly with location and time. In recent years, the SPICAM UV spectrometer on board Mars Express has shown the presence of two distinct ozone layers at low-to-mid latitudes.


In the new study, Dr Franck Montmessin and Dr Franck Lefèvre, both from LATMOS in Guyancourt, France, have analyzed about 3,000 occultation sequences and vertical ozone profiles collected by SPICAM on the night side of Mars and then compared the data with a global climate model, LMD, to detect a previously unknown ozone layer located at heights of 35 – 70 km, with a peak concentration at 50 km. This layer shows an abrupt decrease in elevation between 75 and 50 degrees South.

 

The third ozone layer was found to exist only above the winter pole. SPICAM detected a gradual increase in ozone concentration at 50 km until midwinter, after which it slowly decreased to very low concentrations, with no layer perceptible above 35 km.

 

Dr Montmessin and Dr Lefèvre believe that the observed polar ozone layers are the result of the same atmospheric circulation pattern that creates a distinct oxygen emission recently identified in the polar night. This circulation takes the form of a huge Hadley cell in which warmer air rises and travels poleward before cooling and sinking at higher latitudes.

 

“This process consists of deep vertical downwelling of oxygen-rich air which has been transported from the summer hemisphere,” said first author Dr Franck Montmessin.

 

“Oxygen atoms produced by CO2 photolysis in the upper branch of the Hadley cell eventually recombine in the polar night to form molecular oxygen and ozone. The concentration of ozone gas at night is dependent upon the supply of oxygen and the rate of destruction due to hydrogen radicals.”

 

“This ozone-forming process has no counterpart on the Earth, so Mars provides an example of how diverse and complex chemical processes can be in the atmospheres of terrestrial planets and how they may potentially operate on exoplanets.”

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3D printed objects outgrow their printers: How to create really big objects?

3D printing may be set to change the world by letting us make all sorts of bespoke objects, but there's one little problem: the printers can only print items smaller than themselves. Until now, that is.

 

Skylar Tibbits at the Massachusetts Institute of Technology's Self-Assembly Lab and colleague Marcelo Coelho have come up with a way for standard 3D printers to print out large-scale objects. "It's challenging the notion that we always need a machine that's bigger than the thing it's printing," says Tibbits.

The approach, called Hyperform, converts the object to be printed into a single long chain made from interlocking links. An algorithm works out how that chain can be packed together into the smallest cube possible using a Hilbert curve – a fractal-based pattern that is the most efficient way of squeezing a single line into a small as space as possible. The resulting cube is small enough to be printed inside a standard printer.

Once this cube is printed, the chain can be unravelled and assembled by hand to create the desired object. That's possible because each link in the chain has notches that allow it to bend only in a certain way. "You have to fold it by hand and click it into place," says Tibbits. Hyperform won the "The Next Idea" prize at the Ars Electronica 2013 technology festival in Linz, Austria, earlier this month.

But printing cubes made of such densely packed chains was too much for most of the consumer printers that Tibbits and his team tried. "We blew a lot of printers at first," he says. So they teamed up with Formlabs who, after a successful Kickstarter crowdfunding campaign, have just started shipping their Form 1 3D printer.

 

The Form 1 is capable of much higher resolution than standard consumer 3D printers. Instead of printing out layer upon layer of plastic, it uses stereolithography, in which a pool of liquid plastic is added to the base of the printer and a laser traces out the pattern required, causing the liquid plastic to cure and solidify. The technique can form layers just 25 microns thick, with details as small as 300 microns.

 

Hyperform has so far been used to create large structures such as a chandelier, and Tibbits sees it as being perfect for producing large 3D-printed consumer products. But the Form 1 printer uses resins which have limitations in terms of strength. "There is a range of things that are largish that we can do right away," says Tibbits. "But if you want to make large-scale furniture or buildings, there needs to be an approach to make them stronger."

Manually clicking each link into place isn't ideal either. That's where Tibbits' other work in so-called 4D printing might help. 4D printing uses materials that are 3D-printed to produce an intermediate object which, when exposed to water, will bend and twist itself into the final structure. "You can see how Hyperform and 4D printing are pointing towards each other," he says.

Clément Moreau, CEO of French 3D printing firm Sculpteo, says projects like Hyperform are shaping the future of 3D printing. "This is yet another example of how 3D printing is more of a flexible manufacturing process than injection moulding because it constantly opens up new possibilities in terms of materials used and shapes which can be printed."

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Undoing Down syndrome? Sonic Hedgehog reverses learning deficits in mice with trisomy 21 traits

Undoing Down syndrome? Sonic Hedgehog reverses learning deficits in mice with trisomy 21 traits | Amazing Science | Scoop.it

For people with trisomy 21 – more commonly known as Down syndrome – learning and remembering important concepts can be a struggle, since some of their brain’s structures do not develop as fully as they should.

But now, researchers may have found a way to reverse the learning deficits associated with Down syndrome, after having discovered a compound that can significantly bolster cognition in mice with a condition very similar to trisomy 21.

 

In a new study published in the Sept. 4 issue of Science Translational Medicine, scientists injected a small protein known as a sonic hedgehog pathway agonist into the brains of genetically engineered mice on the day of their birth.  The treatment enabled the rodents’ cerebellums to grow to a normal size, allowing them to perform just as well as unmodified mice in behavioral tests.

 

“We’ve been working for some time to characterize the basis for how people with trisomy 21 diverge in development from people without trisomy 21,” Roger Reeves, a professor in the McKusick-Nathans Institute of Genetic Medicine at the Johns Hopkins University School of Medicine, told FoxNews.com. “One of the early things we see is that people with Down syndrome have very small cerebellums, which does a lot more things than we used to think it did.”

 

Down syndrome is a condition that occurs when people receive three – rather than the typical two – copies of chromosome 21. Because of this “trisomy,” Down syndrome patients have extra copies of the more than 300 genes contained in that chromosome.  This leads to a range of symptoms, including mild to moderate intellectual disability, distinct facial features, heart defects and other health problems.

 

Through previous research, Reeves found that another distinct trait of people with Down syndrome is a cerebellum that’s approximately 60 percent of the normal size.  In order for this important brain region to grow and form, a small population of cells in the brain must quickly divide and multiply shortly after birth. This cell population requires a specific growth factor known as the sonic hedgehog pathway to stimulate the cells, triggering them to divide.

 

However, the trisomic cells in people with Down syndrome do not respond as well to this growth factor, stunting the development of the cerebellum – a region of the brain found to be important in cognitive processing and emotional control.

 

“We thought if we could stimulate these cells a bit at birth, we could make up the deficit,” Reeves said.  To test this theory, Reeves and his research team created a series of genetically engineered mice, all of which had extra copies of about half of the genes found in chromosome 21.  According to Reeves, this caused the mice to have many of the same characteristics seen in patients with Down syndrome, such as a smaller cerebellum and learning difficulties.

 

The researchers then injected the mice with a sonic hedgehog pathway agonist, which stimulates the growth factor pathway needed to trigger cerebellum development.   The compound was given to the mice just once on the day of birth. “From that one injection, we were able to normalize the growth of the cerebellum, and they continued to have a structurally normal cerebellum when they grew up,” Reeves said.

 

Going one step further, the researchers conducted a series of behavioral tests on the mice to better understand how normalizing this brain structure would affect their overall performance.  One of these tests was the Morris water maze test, an experiment that involves placing the mice in a pool of water and seeing how long it takes them to escape using a platform hidden below the water’s surface.  The test measures the rodents’ spatial learning and memory capabilities, which are primarily controlled by the hippocampus.

 

The sonic hedgehog agonist has yet to be proven effective in humans with Down syndrome, and future research is needed to determine exactly how the injection improved the mice’s cognitive abilities and whether or not the agonist has any side effects.  But Reeves remains hopeful that these findings could have translational potential.

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Elizabeth W.'s curator insight, March 25, 2014 10:40 AM

This article is proposing the possibility of treating people born with Down syndrome. It has been found that people with Down syndrome  have cerebellum's that are 60% of the size of a normal cerebellum which we plays a part in our cognitive and emotional functioning. The researchers are now studying if they can help the cerebellum grow at birth with an injected agonist. The study has been done with mice and showed some promising results but whether or not the mice are healthy overall still hasn't been determined. It will also take awhile before this is used on anybody with Down syndrome. 

If this is able to work and show promising results to help people with Down syndrome, it would be an amazing and radical change. However, from my perspective it seems that this type of thing would naturally have costs or risks associated with injecting the agonist and also there could be some ethical issues. "Do I inject my child with this agonist in hopes they will not experience the obstacles with Down syndrome or do I not knowing there could be a risk child?" I'm not sure what procedures would be taken place for this but I could see this issue coming up. 

Nick Ure's curator insight, December 17, 2014 11:18 AM

?- Questions 

Star- Important

Vocab- words you dont understand

HgI- How you get it

E- Effects on Life

D- Description of disease

 

in text citation (tristomy)

 

Vocab- Trisomy also know as down syndrome

 

E- Learning and remembering important concepts can be a real struggle  

 

E- Their brain structure does not fully develop as fully as they should

 

* They injected a small molecule known as a sonic hedgehog pathway agonist  into the brains of little mice that just were born. it enabled them to grow a normal size, allowing them to perform just as well.

 

D- One thing we see is that people with down syndrome have very small cerebellums.

 

D- Down syndrome is a common condition that occurs when people receive three. Than a two copies of chromosome 21. Patients have extra copies of more than 300 genes in the chromosome. This will lead to many symptoms like mild to moderate intellectual disability, distinct features, heart and other problems.

 

Cerebellum- is a region of the brain that plays an important role in motor control

 

HgI- If a small population of cells in the brain dont quickly divide and multiply shortly after birth you could get it. This requirers a current growth factor known as the sonic hedgehog pathway to stimulate the cells.  

 

D- They thought they could fix this disease a bit and they tried there medicine on mice first. They would inject them one on the day of birth.  From this one inject they are able to normalize the growth of the cerebellum and they continue to have a normal Cerebellum when they grow up. 

 

* This medicine has yet to be texted on humans with this disability and future research will be needed before they try and find how what the injection will do and why it improves the micas abilities. They dont know yet if it has side effects yet. If this works that would be amazing cause it could help a lot of people with down syndrome. 

 

 

 

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Description and first application of a new technique to measure the gravitational mass of antimatter

Description and first application of a new technique to measure the gravitational mass of antimatter | Amazing Science | Scoop.it

Researchers at Cern in Switzerland have tested a novel way to find out if antimatter is the source of a force termed "antigravity". Antimatter particles are the "mirror image" of normal matter, but with opposite electric charge.

How antimatter responds to gravity remains a mystery, however; it may "fall up" rather than down.

 

Now researchers reporting in Nature Communications have made strides toward finally resolving that notion. Antimatter presents one of the biggest mysteries in physics, in that equal amounts of matter and antimatter should have been created at the Universe's beginning.


Yet when the two meet, they destroy each other in what is called annihilation, turning into pure light. Why the Universe we see today is made overwhelmingly of matter, with only tiny amounts of antimatter, has prompted a number of studies to try to find some difference between the two.

 

Tests at Cern's LHCb experiment and elsewhere, for example, have been looking for evidence that exotic particles decay more often into matter than antimatter.

 

Last week, the LHCb team reported a slight difference in the decay of particles called Bs mesons - but still not nearly enough to explain the matter mystery.

 

One significant difference between the two may be the way they interact with gravity - antimatter may be repelled by matter, rather than attracted to it.

But it is a difference that no one has been able to test - until the advent of Cern's Alpha experiment. It's the first time that anyone has even been able to talk about doing this”, says Jeffrey Hangst, Alpha experiment spokesperson.


There are many compelling experimental and theoretical arguments that suggest that the gravitational mass of antimatter cannot differ from the gravitational or inertial mass of normal matter, that is, that the weak equivalence principle holds. For instance, one such argument comes from the absence of anomalies in Eötvös experiments conducted with differing atoms; the differing number of virtual particle–antiparticle pairs in such atoms might have caused gravitational anomalies to occur. However, all of these arguments are indirect and are not universally accepted. They rely on assumptions about the gravitational interactions of virtual antimatter, on postulates such as CPT invariance, or on other theoretical premises.

 

Although these arguments may well be correct, in a world in which physicists have only recently discovered that we cannot account for most of the matter and energy in the universe, it would be presumptuous to categorically assert that the gravitational mass of antimatter necessarily equals its inertial mass.

 

Moreover, the baryogenesis problem suggests that our understanding of antimatter is incomplete; gravitational asymmetries have been proposed as an explanation. 

 

There have not yet been any direct, free-fall or gravitational balance, tests of the gravitational interactions of observable matter and antimatter. Direct gravitational experiments with non-neutral antimatter, for example, isolated positrons or antiprotons, are exceedingly difficult because the electrical forces overwhelm the gravitational forces. Employing neutral antihydrogen or positronium eliminates this complication. The AEGIS project at CERN was formed to conduct direct experimental tests of gravity on antihydrogen, and is now in its final construction phase. A second experiment, GBAR, has recently been approved at CERN, and a third experiment was proposed at Fermilab.

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How to make ceramics that bend without breaking: Self-deploying medical devices?

How to make ceramics that bend without breaking: Self-deploying medical devices? | Amazing Science | Scoop.it
New materials could lead to actuators on a chip and self-deploying medical devices. Ceramics are not known for their flexibility: they tend to crack under stress.

 

The team has developed a way of making minuscule ceramic objects that are not only flexible, but also have a "memory" for shape: When bent and then heated, they return to their original shapes. The surprising discovery is reported this week in the journalScience, in a paper by MIT graduate student Alan Lai, professor Christopher Schuh, and two collaborators in Singapore.


Shape-memory materials, which can bend and then snap back to their original configurations in response to a temperature change, have been known since the 1950s, explains Schuh, the Danae and Vasilis Salapatas Professor of Metallurgy and head of MIT's Department of Materials Science and Engineering. "It's been known in metals, and some polymers," he says, "but not in ceramics."

 

In principle, the molecular structure of ceramics should make shape memory possible, he says -- but the materials' brittleness and propensity for cracking has been a hurdle. "The concept has been there, but it's never been realized," Schuh says. "That's why we were so excited."

 

The key to shape-memory ceramics, it turns out, was thinking small.

 

The team accomplished this in two key ways. First, they created tiny ceramic objects, invisible to the naked eye: "When you make things small, they are more resistant to cracking," Schuh says. Then, the researchers concentrated on making the individual crystal grains span the entire small-scale structure, removing the crystal-grain boundaries where cracks are most likely to occur.

Those tactics resulted in tiny samples of ceramic material -- samples with deformability equivalent to about 7 percent of their size. "Most things can only deform about 1 percent," Lai says, adding that normal ceramics can't even bend that much without cracking.

 

"Usually if you bend a ceramic by 1 percent, it will shatter," Schuh says. But these tiny filaments, with a diameter of just 1 micrometer -- one millionth of a meter -- can be bent by 7 to 8 percent repeatedly without any cracking, he says.

 

While a micrometer is pretty tiny by most standards, it's actually not so small in the world of nanotechnology. "It's large compared to a lot of what nanotech people work on," Lai says. As such, these materials could be important tools for those developing micro- and nanodevices, such as for biomedical applications. For example, shape-memory ceramics could be used as microactuators to trigger actions within such devices -- such as the release of drugs from tiny implants.


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A hidden genetic code for better designer genes

A hidden genetic code for better designer genes | Amazing Science | Scoop.it

Scientists routinely seek to reprogram bacteria to produce proteins for drugs, biofuels and more, but they have struggled to get those bugs to follow orders. But a hidden feature of the genetic code, it turns out, could get bugs with the program. The feature controls how much of the desired protein bacteria produce, a team from the Wyss Institute for Biologically Inspired Engineering at Harvard University reported in the September 26 online issue of Science.

The findings could be a boon for biotechnologists, and they could help synthetic biologists reprogram bacteria to make new drugs and biological devices.

 

By combining high-speed "next-generation" DNA sequencing and DNA synthesis technologies, Sri Kosuri, Ph.D., a Wyss Institute staff scientist, George Church, Ph.D., a core faculty member at the Wyss Institute and professor of genetics at Harvard Medical School, and Daniel Goodman, a Wyss Institute graduate research fellow, found that using more rare words, or codons, near the start of a gene removes roadblocks to protein production.

"Now that we understand how rare codons control gene expression, we can better predict how to synthesize genes that make enzymes, drugs, or whatever you want to make in a cell," Kosuri said.

 

To produce a protein, a cell must first make working copies of the gene encoding it. These copies, called messenger RNA (mRNA), consist of a specific string of words, or codons. Each codon represents one of the 20 different amino acids that cells use to assemble proteins. But since the cell uses 61 codons to represent 20 amino acids, many codons have synonyms that represent the same amino acid.

 

In bacteria, as in books, some words are used more often than others, and molecular biologists have noticed over the last few years that rare codons appear more frequently near the start of a gene. What's more, genes whose opening sequences have more rare codons produce more protein than genes whose opening sequences do not.

 

No one knew for sure why rare codons had these effects, but many biologists suspected that they function as a highway on-ramp for ribosomes, the molecular machines that build proteins. According to this idea, called the codon ramp hypothesis, ribosomes wait on the on-ramp, then accelerate slowly along the mRNA highway, allowing the cell to make proteins with all deliberate speed. But without the on-ramp, the ribosomes gun it down the mRNA highway, then collide like bumper cars, causing traffic accidents that slow protein production. Other biologists suspected rare codons acted via different mechanisms. These include mRNA folding, which could create roadblocks for ribosomes that block the highway and slow protein production.

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Astronomers Uncover a Millisecond 'Transformer' Pulsar with Magnetic Field Structure

Astronomers Uncover a Millisecond 'Transformer' Pulsar with Magnetic Field Structure | Amazing Science | Scoop.it

An international team of scientists using a fleet of orbiting X-ray telescopes, including NASA's Swift and Chandra X-ray Observatory, has discovered a millisecond pulsar with a dual identity. In a feat that has never before been observed, the star readily shifts back and forth between two mutually exclusive styles of pulsed emission -- one in X-rays, the other in radio.

 

The discovery, say scientists, represents a long-sought intermediate phase in the life of these powerful objects.

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Ancient oxygen discovery - 700 million years earlier - shakes up history of life on Earth

Ancient oxygen discovery - 700 million years earlier - shakes up history of life on Earth | Amazing Science | Scoop.it

Oxygen appeared in the Earth’s atmosphere up to 700 million years earlier than thought, according to a study led by a B.C. scientist, suggesting that revisions need to be made to current theories about how life evolved on Earth.

Up until now, scientists thought photosynthesis — the ability of living things such as algae and plants to harvest energy from the sun  — first evolved in single-celled organisms about 2.7 billion years ago.

 

Because oxygen is produced during photosynthesis, early photosynthetic organisms are thought to have given rise to the Great Oxygenation Event, also known as the Great Oxidation Event, about 2.3 billion years ago.

The incident was thought to be the first time the atmosphere began accumulating significant amounts of oxygen. That is significant because complex multicellular organisms such as humans require an oxygen-rich atmosphere to survive.

 

The new study led by biogeochemist Sean Crowe has found surprising evidence that as far back as three billion year ago, there were levels of oxygen in the atmosphere too high to have been produced without living organisms.

 

Crowe, an assistant professor in the department of Microbiology and Immunology and the department of Earth, Ocean and Atmospheric Sciences at the University of British Columbia, said people have detected traces of oxygen before in samples older than 2.3 billion years, but the signals were never strong enough to make a conclusion. That is partly because most ancient samples analyzed were marine sediments from the bottom of the ocean, which aren’t in direct contact with the atmosphere, and therefore don’t show very strong oxygen signals at the best of times.


However, researchers in South Africa recently discovered an ancient land-based soil sample called a paleosol that dated back three billion years.

Crowe, in collaboration with colleagues at the University of Southern Denmark, where he was previously a postdoctoral researcher, decided to test the samples for oxygen. The researchers employed a new, more sensitive technique that involves looking for forms of chromium that only occur following reaction with oxygen.

 

Given the age of the samples, Crowe didn’t expect to find any oxygen. So he was surprised when the tests showed “low but appreciable concentrations.”

 “Initially we thought we must have done something wrong or there was something wrong with the samples,” Crowe said.

 

To verify the results, researchers tested marine samples that were about the same age. Using the new chromium technique, they too showed a positive signal for oxygen.

 

“We were very excited,” Crowe said. “Immediately we knew there was oxygen in the atmosphere well before we understood it to be.”

 

The oxygen levels detected in the samples were only a 10,000th of present day levels of 20 per cent of the atmosphere, and a 200th to a 500th of the levels that immediately followed the Great Oxygenation Event.


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Wesley M Leonhardt's comment, October 1, 2013 8:34 PM
The earth's history will always be a mystery, and this article proves it. We have always been taught that the first oxygen on earth came from single celled organisms doing photosynthesis. This new study shows evidence of oxygen existing before these singled celled organisms. Using a soil sample called a paleosol, they discovered proof of oxygen in the soil billions of years ago. Even though oxygen levels were not as high as they are today, it still is a huge scientific discovery that will affect the learning of people in the future.
Wesley M Leonhardt's comment, October 1, 2013 8:39 PM
I feel like this will really affect the scientific thought of the evolution of the earth. The order of evolution will have to be reworked (yay for Adam and Eve!). I do believe that the earth will always have mysteries that we cant solve, but we can always try to solve them.
Wesley M Leonhardt's comment, October 1, 2013 8:41 PM
Chung, Emily. "Ancient Oxygen Discovery Shakes up History of Life on Earth - Technology & Science - CBC News." CBCnews. CBC/Radio Canada, 25 Sept. 2013. Web. 01 Oct. 2013. <http://www.cbc.ca/news/technology/ancient-oxygen-discovery-shakes-up-history-of-life-on-earth-1.1867976>.
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Breakthrough: A man controls robotic leg using thoughts alone

A man missing his lower leg has gained precise control over a prosthetic limb, just by thinking about moving it – all because his unused nerves were preserved during the amputation and rerouted to his thigh where they can be used to communicate with a robotic leg.

 

The man can now seamlessly switch from walking on level ground to climbing stairs and can even kick a football around.

 

During a traditional limb amputation, the main sensory nerves are severed and lose their function. In 2006, Todd Kuiken and his colleagues at the Rehabilitation Institute of Chicago in Illinois realised they could preserve some of that functionality by carefully rerouting sensory nerves during an amputation and attaching them to another part of the body.

They could then use the rerouted nerve signals to control a robotic limb, allowing a person to control their prosthesis with the same nerves they originally used to control their real limb.

 

Kuiken's team first attempted the procedure – which is called targeted muscle reinnervation (TMR) – on people who were having their arm amputated. Now, Kuiken's team has performed TMR for the first time on a man with a leg amputation.

 

First, the team rerouted the two main branches of the man's sciatic nerve to muscles in the thigh above the amputation. One branch controls the calf and some foot muscles, the other controls the muscle running down the outside leg and some more foot muscles.

 

After a few months, the man could control his thigh muscles by thinking about using his missing leg. The next step was to link up a prosthesis.

 

The robot leg in question is a sophisticated prosthesis: it carries a number of mechanical sensors including gyroscopes and accelerometers, and can be trained to use the information from these sensors to perform certain walking styles. Kuiken's team reckoned that the leg would perform even better if it could infer the user's intended walking style with information from the sciatic nerve.

 

To do so, the researchers asked their volunteer to attempt to perform certain movements with his missing leg – for instance, flexing the foot – while they monitored the pattern of electric signals from the rerouted nerves in the thigh muscles. The researchers then programmed the robot leg to flex its foot whenever it detected that particular pattern of electrical activity.

 

Using just the mechanical sensor data, the robotic leg made the correct movement about 87 per cent of the time. With additional data from the nerves, the success rate rose to 98 per cent, and there were no so-called critical errors – errors that increase the risk of the user losing balance and falling. Those kinds of errors are most common when the user suddenly shifts walking style – when they begin to climb stairs, for instance, but with the additional information from the nerves, the robotic leg can make a seamless, natural transition between walking styles (see video).

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Carlos Garcia Pando's comment, September 27, 2013 3:11 AM
Great idea. Thanks for posting
Madison Punch's comment, April 13, 2014 2:51 PM
Aha, where psychology meets physiology. I think this is amazing and definitely the best way for prosthetic limb users to activate their faux leg/arm/etc. Very cool!
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Light-bending through a proton sphere as an artificial black hole mimicking curved spacetime

Light-bending through a proton sphere as an artificial black hole mimicking curved spacetime | Amazing Science | Scoop.it

It isn't dangerous – but the plastic black hole is helping to demystify one of nature's weirdest objects and might have applications for energy-harvesting.

 

A plastic black hole traps light just like the real deal, and is the first such structure, natural or artificial, that you can actually watch in action. Unlike the real thing, it isn't dangerous – but it is helping to demystify one of nature's weirdest objects and might even have applications for energy-harvesting devices like solar cells.

 

Black holes are most famous for swallowing light, or anything else in their path. But this fate only awaits objects that get sucked past a point called the event horizon. Less well known is a black hole's photon sphere, a region of warped space-time outside the horizon that merely traps light in curved paths. Astronomers have never observed a photon sphere – even outside genuine black holes – because, by definition, trapped light can't escape and reach your eyes so you can see it.

 

So to visualise this process, Hui Liu at Nanjing University in China and colleagues built an artificial black hole.

 

In nature, black holes swallow and trap light via their immense gravity, something that would be difficult, not to mention incredibly dangerous, to recreate in the lab. Instead, Liu's team used a sheet of plastic – and mimicked the effect of gravity by varying its refractive index, the property that determines how much a substance bends light.

 

The refractive index is different for different materials. That is why a straw poking out of a glass of water appears crooked: water bends light more than air, so has a higher refractive index. A material with a constantly varying refractive index would take this to the extreme, with lots of little bends creating a smooth curve – rather like a black hole's photon sphere.

 

Liu's team added quantum dots, tiny pieces of semiconducting material that fluoresce when illuminated, to molten acrylic glass, then poured the mixture onto a rotating quartz sheet, slowly spreading it out.

 

They placed a microscopic polystyrene sphere at the centre, which served as an anchor, with the material thickest nearest the sphere and thinning as it got further away. "This makes the effective refractive index vary in the same way the curvature of space varies around black holes," says Liu. In fact, the same Einstein field equations used to model black holes can describe the behaviour of light in the acrylic.

 

Shining a laser through the material allows you to watch the artificial black hole in action – and to visualise other familiar gravitational effects.

Beams that are relatively far away from the microsphere are slightly bent towards it before continuing on their way. When gravity causes the same effect in space, it is known as gravitational lensing. This occurs whenever a light beam passes a massive object such as a star or galaxy, altering the beam's path as it travels along curved space-time- and can be used to get a better view of distant objects, such as exoplanets.

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See The World's First Images Of Actual Hydrogen Bonds

See The World's First Images Of Actual Hydrogen Bonds | Amazing Science | Scoop.it

Scientists have just seen for the first time one of the most important physical interactions in our world — the special type of bond called the hydrogen bond that holds our DNA together and gives water its unique properties, including surface tension.

 

When a tiny hydrogen atom is in a molecule with a much bigger atom, like nitrogen or oxygen (for example, in water), that larger atom, pulls away some of the negative charge from the smaller one, giving it a slightly positive charge on one edge. That slightly positive charge is electrically attracted to the positive charge on the large atom of another molecule.

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By triggering or silencing certain brain cells, mice eat or stop eating regardless of hunger

By triggering or silencing certain brain cells, mice eat or stop eating regardless of hunger | Amazing Science | Scoop.it

By hijacking connections between neurons deep within the brain, scientists forced full mice to keep eating and hungry mice to shun food. By identifying precise groups of cells that cause eating and others that curb it, the results begin to clarify the intricate web of checks and balances in the brain that control feeding.

 

“This is a really important missing piece of the puzzle,” says neuroscientist Seth Blackshaw of Johns Hopkins University in Baltimore. “These are cell types that weren’t even predicted to exist.” A deeper understanding of how the brain orchestrates eating behavior could lead to better treatments for disorders such as anorexia and obesity, he says.

 

Scientists led by Joshua Jennings and Garret Stuber of the University of North Carolina at Chapel Hill genetically tweaked mice so that a small group of neurons would respond to light. When a laser shone into the brain, these cells would either fire or, in a different experiment, stay quiet. These neurons reside in a brain locale called the bed nucleus of the stria terminalis, or BNST. Some of the message-sending arms of these neurons reach into the lateral hypothalamus, a brain region known to play a big role in feeding.

 

When a laser activated these BNST neurons, the mice became ravenous, voraciously eating their food, the researchers report in the Sept. 27, 2013 Science. “As soon as you turn it on, they start eating and they don’t stop until you turn it off,” Stuber says. The opposite behavior happened when a laser silenced BNST neurons’ messages to the lateral hypothalamus: The mice would not eat, even when hungry.

 

The results illuminate a complex network of neuron connections, in which some cells boost other neurons’ activity, while other cells apply brakes. In the experiment, stimulating BNST neurons with light — which consequently shut down the activity of neurons in the lateral hypothalamus — led to the overeating behavior, the team found. That result suggests that these lateral hypothalamus neurons normally restrict feeding.

 

That finding is surprising, says Blackshaw. Earlier experiments hinted that these hypothalamic cells would encourage eating behavior, but the new study suggests the exact opposite.

 

The researchers don’t know whether, if they controlled the neurons for long periods, the mice would ultimately starve or overeat to the point of illness. Stuber and colleagues used the laser technique, called optogenetics, in roughly 20-minute bursts. Longer-term manipulations of these neural connections — perhaps using a drug — might cause lasting changes in appetite and, as a result, body mass, Stuber says.

 

This precise control of feeding behavior underscores the fact that eating disorders occur when brain systems go awry, Stuber says. “We think of feeding in terms of metabolism and body stuff,” he says. “But at the end of the day, it’s controlled by the brain.”

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For a robot, control is good, freedom is better and a chaotic system will stabilize itself

For a robot, control is good, freedom is better and a chaotic system will stabilize itself | Amazing Science | Scoop.it
Chaos, as found in robot control systems, can be stabilised quicker with less control.

 

When chaos threatens, speed is essential; for example, when a pacemaker needs to stabilise an irregular heartbeat or a robot has to react to the information received from its environment. Both cases require imposing a stable, organised state on a chaotic system. Scientists from the Max Planck Institute for Dynamics and Self-Organization in Göttingen, the Bernstein Center for Computational Neuroscience Göttingen and the University of Göttingen have developed a method for accelerating control. The key to success: A less invasive approach that cleverly exploits the natural behaviour of the system.


When the ground beneath Amos starts to rise, the insectoid robot can skilfully adapt to the changing conditions. After only a moment’s hesitation, he autonomously switches gait and selects a different movement pattern for his six legs, suitable for climbing the slope. To do this, Amos’ “brain”, a comparatively tiny network with few circuits, has to work at full tilt. Can this “thought process” be accelerated? Scientists in Göttingen think so. Their calculations show how Amos’ reaction times can be significantly reduced.

 

The autonomous six-legged robot was developed three years ago and subsequently optimised by a team led by theoretical physicist Marc Timme, who, together with his Research Group, works at the Max Planck Institute for Dynamics and Self-Organization and headed the new study along with robotics expert Poramate Manoonpong from the University of Göttingen. However, the new method is not just suitable for robots such as Amos; basically, it can be applied to any chaotic system where a certain degree of control is required. “Every chaotic system is very susceptible to interference”, Marc Timme explains. Even the smallest external change may trigger a completely different behaviour. In Amos’ case, chaos means that his “brain” would produce a chaotic activity pattern with signals flying in all directions.

 

In order to organise this chaotic pattern, the system requires help. Scientists speak of “chaos control”. The most common methods used begin by trying to calculate the behaviour of the system in the near future. The second step is to transform this information into a control signal which is used to correct the development of the system – a gentle nudge to bring it back on track.

 

However, the Göttingen-based research team has demonstrated that less intervention can be more effective. “The trick is to limit the number of times we push the system towards the required stable state”, says Max Planck researcher Christian Bick. “By giving the system the freedom to develop on its own from time to time, we achieve the desired result faster.”  Physicists call this a self-organised process.

 

“At first glance, this method may seem roundabout”, Bick admits. However, the self-stabilisation of the system is actually very efficient and fast. Only occasional external interventions are required to make sure that the path chosen by the system does not deviate from the right track. Depending on the system, the new method may easily be 100 or 1000 times faster, and requires significantly fewer interventions. “What’s more, theoretically this would permit stabilisation of very complex movement patterns for Amos”, Timme adds.

 


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How Many Earths? Interactive Kepler Data

How Many Earths? Interactive Kepler Data | Amazing Science | Scoop.it

This interactive graphic is based on the data for candidate planets identified by NASA's Kepler Space Telescope. Kepler found these planets by recording the slight dimming of the light from a star caused by a planet passing in front of it.

 

About 10 per cent of the candidate planets will probably turn out to be no such thing – it's possible to mistake the second star in a binary star system for a giant planet, for example. On the other hand, Kepler probably missed around 10 per cent of the planets that passed in front of target stars because the dimming of the star's light was too slight to detect against the natural variability in the stars' light output. These two numbers roughly cancel each another out, so they are not included in our calculations.

 

The first step in answering "How many Earths?" was to ignore planets twice the Earth's diameter or larger: these are likely to be gas giants like Jupiter, not rocky worlds like ours. However, such planets may possess rocky moons, which could well host life.

 

Not all of the remaining planets will be hospitable to life. For example, carbon-rich planets could have a graphite crust with layers of diamond below and rivers of oil and tar.

 

Kepler could not determine a planet's composition, but to calculate how many planets might be friendly to life, we estimated the number in stars' habitable zones – orbits where a planet will be neither too hot nor too cold for water to exist in liquid form.

 

Defining a star's habitable zone is a complex process, but as a reasonable proxy we used Kepler's estimates of planets' equilibrium temperature. This is the temperature that would be measured at a planet's surface if it were a black body heated by its parent star without any atmospheric greenhouse effect.

 

The next step – the most uncertain part of our quest – was extrapolating to the total number of roughly Earth-sized planets likely to be orbiting Kepler's 150,000 target stars. Simple geometry tells us that Kepler will have missed most of these planets: the tilts of their orbits mean they never passed between their parent stars and the telescope. And the farther out a planet orbits, the harder it was for Kepler to detect.

 

Taking everything into account, the best estimate for the average number of roughly Earth-sized planets in each star's habitable zone is 0.15, according to simulations based on Kepler data thatCourtney Dressing and David Charbonneau of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, performed. Applying this average to Kepler's 150,000 target stars gave our estimate of 22,500 potentially habitable, roughly Earth-sized planets.

 

There is an important caveat, though. Dressing and Charbonneau's calculations are for class M stars, which have a reddish hue and account for about three-quarters of the stars in our galaxy. But about 80 per cent of Kepler's target stars are class G stars, like our sun, which are yellowish. Nobody knows for sure whether these different classes of stars have similar populations of planets.

 

The final step in our quest was to extrapolate to the entire galaxy. Estimates of the number of stars in the Milky Way vary from 100 billion to 200 billion. Applying the same estimate of 0.15 potentially Earth-like planets per star gave our figure of between 15 and 30 billion.

 

If we had displayed all these potential planets in the final view, the sky would have become a mass of green. To give a meaningful view for someone here on Earth, we selected stars from the European Space Agency's Tycho-2 catalogue with an apparent magnitude of 10.5 or brighter – these stars would be visible on a dark night with a good pair of binoculars. We have displayed a random sample of 15 per cent of these stars, corresponding to Dressing and Charbonneau's estimate of stars with potentially habitable, roughly Earth-sized planets.

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The Planetary Archives / San Francisco, California's curator insight, September 30, 2013 3:56 PM

2500 years ago, the Buddha is said to have remarked that there are "many, many" planets with beings just like us..... 

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New gut bacterium discovered mainly responsible for termites' capability to digest wood

New gut bacterium discovered mainly responsible for termites' capability to digest wood | Amazing Science | Scoop.it

When termites munch on wood, the small bits are delivered to feed a community of unique microbes living in their guts, and in a complex process involving multiple steps, these microbes turn the hard, fibrous material into a nutritious meal for the termite host. One key step uses hydrogen to convert carbon dioxide into organic carbon -- a process called acetogenesis -- but little is known about which gut bacteria play specific roles in the process. Utilizing a variety of experimental techniques, researchers from the California Institute of Technology (Caltech) have now discovered a previously unidentified bacterium -- living on the surface of a larger microorganism in the termite gut -- that may be responsible for most gut acetogenesis.

 

"In the termite gut, you have several hundred different species of microbes that live within a millimeter of one another. We know certain microbes are present in the gut, and we know microbes are responsible for certain functions, but until now, we didn't have a good way of knowing which microbes are doing what," says Jared Leadbetter, professor of environmental microbiology at Caltech, in whose laboratory much of the research was performed.

 

Acetogenesis is the production of acetate (a source of nutrition for termites) from the carbon dioxide and hydrogen generated by gut protozoa as they break down decaying wood. In their study of "who is doing what and where," Leadbetter and his colleagues searched the entire pool of termite gut microbes to identify specific genes from organisms responsible for acetogenesis.

 

The researchers began by sifting through the microbes' RNA -- genetic information that can provide a snapshot of the genes active at a certain point in time. Using RNA from the total pool of termite gut microbes, they searched for actively transcribed formate dehydrogenase (FDH) genes, known to encode a protein necessary for acetogenesis. Next, using a method called multiplex microfluidic digital polymerase chain reaction (digital PCR), the researchers sequestered the previously unstudied individual microbes into tiny compartments to identify the actual microbial species carrying each of the FDH genes. Some of the FDH genes were found in types of bacteria known as spirochetes -- a previously predicted source of acetogenesis. Yet it appeared that these spirochetes alone could not account for all of the acetate produced in the termite gut.

 

Initially, the Caltech researchers were unable to identify the microorganism expressing the single most active FDH gene in the gut. However, the first authors on the study, Adam Rosenthal, a postdoctoral scholar in biology at Caltech, and Xinning Zhang (PhD '10, Environmental Science and Engineering), noticed that this gene was more abundant in the portion of the gut extract containing wood chunks and larger microbes, like protozoans. After analyzing the chunkier gut extract, they discovered that the single most active FDH gene was encoded by a previously unstudied species from a group of microbes known as the deltaproteobacteria. This was the first evidence that a substantial amount of acetate in the gut may be produced by a non-spirochete.

 

Because the genes from this deltaproteobacterium were found in the chunky particulate matter of the termite gut, the researchers thought that perhaps the newly identified microbe attaches to the surface of one of the chunks. To test this hypothesis, the researchers used a color-coded visualization method called hybridization chain reaction-fluorescent in situ hybridization, or HCR-FISH.

 

The technique -- developed in the laboratory of Niles Pierce, professor of applied and computational mathematics and bioengineering at Caltech, and a coauthor on the PNAS study -- allowed the researchers to simultaneously "paint" cells expressing both the active FDH gene and a gene identifying the deltoproteobacterium with different fluorescent colors simultaneously. "The microfluidics experiment suggested that the two colors should be expressed in the same location and in the same tiny cell," Leadbetter says. And, indeed, they were. "Through this approach, we were able to actually see where the new deltaproteobacterium resided. As it turns out, the cells live on the surface of a very particular hydrogen-producing protozoan."

 

This association between the two organisms makes sense based on what is known about the complex food web of the termite gut, Leadbetter says. "Here you have a large eukaryotic single cell -- a protozoan -- which is making hydrogen as it degrades wood, and you have these much smaller hydrogen-consuming deltaproteobacteria attached to its surface," he says. "So, this new acetogenic bacterium is snuggled up to its source of hydrogen just as close as it can get."

 

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Biologists Confirm Role of Sperm Competition in Formation of New Species

Biologists Confirm Role of Sperm Competition in Formation of New Species | Amazing Science | Scoop.it

Biologists in Syracuse University’s College of Arts and Sciences have confirmed that reproductive isolation, a critical step in the formation of new species, can arise from diversifying sperm competition. Their findings, which have major implications for the study of biodiversity, are the subject of a groundbreaking article in the Oct. 7th issue of Current Biology (Elsevier, 2013).

 

Female promiscuity—something that occurs in a majority of species, including humans—results in the ejaculates from two or more males overlapping within her reproductive tract. When this happens, sperm compete for fertilization of the female’s eggs. In addition, the female has the opportunity to bias fertilization of her eggs in favor of one male’s sperm over others.

 

These processes, collectively known as postcopulatory sexual selection, drive a myriad of rapid, coordinated evolutionary changes in ejaculate and female reproductive tract traits. These changes have been predicted to be an important part of speciation, the process by which new biological species arise.

 

Until now, traits and processes that influence fertilization success have been poorly understood, due to the challenges of observing what sperm do within the female’s body and of discriminating sperm among different males. Almost nothing is known about what determines the sperm’s fate in hybrid matings where there may be an evolutionary mismatch between ejaculate and female reproductive tract traits.

 

Professor John Belote has overcome these challenges by genetically engineering closely related species of fruit flies with different colors of glow-in-the-dark-sperm. Working closely with Scott Pitnick, Mollie Manier, and other colleagues in SU’s Pitnick Lab, he is able to observe ejaculate-female interactions and sperm competition in hybrid matings.

 

“How new species arise is one of the most important questions facing biologists, and we still have a lot to learn,” says Pitnick, a professor in SU's Department of Biology, adding that the mechanisms maintaining the genetic boundary between species is difficult to pin down. “This paper [in Current Biology] is perhaps the most important one of my career. It has been six years in the making.”

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Number of Confirmed Alien Planets Nears 1,000 (Unconfirmed 3,500)

Number of Confirmed Alien Planets Nears 1,000 (Unconfirmed 3,500) | Amazing Science | Scoop.it

Just two decades after discovering the first world beyond our solar system, astronomers are closing in on alien planet No. 1,000.

 

Four of the five main databases that catalog the discoveries of exoplanets  now list more than 900 confirmed alien worlds, and two of them peg the tally at 986 as of today (Sept. 26). So the 1,000th exoplanet may be announced in a matter of days or weeks, depending on which list you prefer.

 

That's a lot of progress since 1992, when researchers detected two planets orbiting a rotating neutron star, or pulsar, about 1,000 light-years from Earth. Confirmation of the first alien world circling a "normal" star like our sun did not come until 1995.

 

And the discoveries will keep pouring in, as astronomers continue to hone their techniques and sift through the data returned by instruments on the ground and in space.

 

The biggest numbers in the near future should come from NASA'sKepler space telescope, which racked up many finds before being hobbled in May of this year when the second of its four orientation-maintaining reaction wheels failed.

 

Kepler has identified 3,588 planet candidates to date. Just 151 of these worlds have been confirmed so far, but mission scientists have said they expect at least 90 percent will end up being the real deal.

 

But even these numbers, as impressive as they are, represent just the tip of our Milky Way galaxy's immense planetary iceberg. Kepler studied a tiny patch of sky, after all, and it only spotted planets that happened to cross their stars' faces from the instrument's perspective.

 

Many more planets are thus out there, zipping undetected around their parent stars. Indeed, a team of researchers estimated last year that every Milky Way star hosts, on average, 1.6 worlds — meaning that our galaxy perhaps harbors 160 billion planets.

 

And those are just the worlds with obvious parent stars. In 2011, a different research team calculated that "rogue planets" (which cruise through space unbound to a star) may outnumber "normal" exoplanets by 50 percent or so.

 

Nailing down the numbers is of obvious interest, but what astronomers really want is a better understanding of the nature and diversity of alien worlds.

And it's becoming more and more apparent that this diversity is stunning. Scientists have found exoplanets as light and airy as Styrofoam, for example, and others as dense as iron. They've also discovered a number of worlds that appear to orbit in their stars' habitable zone — that just-right range of distances that could support the existence of liquid water and thus, perhaps, life as we know it.

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Human robot getting closer: iCub robot must learn from its experiences

Human robot getting closer: iCub robot must learn from its experiences | Amazing Science | Scoop.it
A robot that feels, sees and, in particular, thinks and learns like us. It still seems like science fiction, but new research hints that it could happen. Scientists are working to implement the cognitive process of the human brain in robots.

 

The research should lead to the arrival of the latest version of the iCub robot in Twente. This human robot (humanoid)blurs the boundaries between robot and human.


Decades of scientific research into cognitive psychology and the brain have given us knowledge about language, memory, motor skills and perception. We can now use that knowledge in robots, but Frank van der Velde's research goes even further. "The application of cognition in technical systems should also mean that the robot learns from its experiences and the actions it performs. A simple example: a robot that spills too much when pouring a cup of coffee can then learn how it should be done."


The arrival of the iCub robot at the University of Twente should signify the next step in this research. Van der Velde submitted an application together with other UT researchers Stefano Stramigioli, Vanessa Evers, Dirk Heylen and Richard van Wezel, all active in the robotics and cognitive research. At the moment, twenty European laboratories have an iCub, which was developed in Italy (thanks to a European FP7 grant for the IIT). The Netherlands is still missing from the list. Moreover, a newer version is currently being developed, with for example haptic sensors. In February it will be announced whether the robotics club will actually bring the latest iCub to the UT. The robot costs a quarter of a million Euros and NWO (Netherlands Organisation for Scientific Research) will reimburse 75% of the costs. Then the TNO (Netherlands Organisation for Applied Scientific Research) and the universities of Groningen, Nijmegen, Delft and Eindhoven can also make use of it. Within the UT, the iCub can be deployed in different laboratories thanks to a special transport system.


The possibilities are endless, according to Van der Velde. "The new iCub has a skin and fingers that have a much better sense of touch and can feel strength. That makes interaction with humans much more natural. We want to ensure that this robot continues to learn and understands how people function. This research ensures, for example, that robots actually gather knowledge by focusing on certain objects or persons. In areas of application like healthcare and nursing, such robots can play an important role. A good example would be that in ten years' time you see a blind person walking with a robot guide dog."


Video: http://www.youtube.com/watch?v=ZcTwO2dpX8A

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Alien frontier: See the haunting, beautiful weirdness of Mars in Hi-Res Pictures

Alien frontier: See the haunting, beautiful weirdness of Mars in Hi-Res Pictures | Amazing Science | Scoop.it

Mounted to the Mars Reconnaissance Orbiter as it floats high above the red planet is the HiRISE telescope, an imaging device capable of taking incredibly high-resolution photos of the martian landscape. It's sent back nearly 30,000 photos during its time above the planet, which have been used by NASA to find clear landing spots for rovers, and by researchers to learn more about the features of Mars' surface.

 

The stunning views captured by HiRISE have inspired a book from the publisher Aperture, called This is Mars, which includes 150 of its finest looks at the planet. The entire collection is in black and white, however, as that's how HiRISE's images naturally turn out.

 

But by combining different color filters on the telescope, NASA is able to produce colored versions of most images too. They're known as "false color" images, since they won't perfectly match up with what the human eye would see. False color images are still useful, however, in helping researchers distinguish between different elements of Mars' landscape. They're also downright gorgeous to look through. Below, we've collected our own series of some of the most incredible sights taken by HiRISE throughout 2013.

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Adrian Rojas's comment, October 7, 2013 11:36 PM
Well I thought Aliens didn't exist? And if they didn't why are they saying they have found alien made things on Mars. I believe in aliens because there is proof but then you hear someone say no and they try to find some scientific way of proving that aliens don't exist. And some of the pictures here don't really show or prove that aliens made them because I could have just been eroded or gravity formed it like that. There is many explanation that these photographs are not alien made because it could of just been naturally made like that.

How do we have photos of Mars if we have never been there? And there was an article that said they have found water on Mars so it's not impossible if there was life on the planet. But you can't just jump on the conclusion that there are aliens on Mars.
Dr. Stefan Gruenwald's comment, October 8, 2013 2:32 AM
Alien in the title is used as an adjective and means "strange, foreign". It has NOTHING to do with actual aliens. Where do you get this idea from?
alenav09's curator insight, October 11, 2013 7:42 PM

Wow aliens that's crazy and to think some people actually think that there are no aliens we'll just wow. If you really think about it then you can see that we can't be the only possible life forms out there!!!!!

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Scientists create never-before-seen form of matter

Scientists create never-before-seen form of matter | Amazing Science | Scoop.it
Harvard and MIT scientists are challenging the conventional wisdom about light, and they didn't need to go to a galaxy far, far away to do it.

 

Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25, 2013, paper in Nature.

 

The discovery, Lukin said, runs contrary to decades of accepted wisdom about the nature of light. Photons have long been described as massless particles which don't interact with each other – shine two laser beams at each other, he said, and they simply pass through one another.

 

"Photonic molecules," however, behave less like traditional lasers and more like something you might find in science fiction – the light saber.

 

"Most of the properties of light we know about originate from the fact that photons are massless, and that they do not interact with each other," Lukin said. "What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules. This type of photonic bound state has been discussed theoretically for quite a while, but until now it hadn't been observed.

 

"It's not an in-apt analogy to compare this to light sabers," Lukin added. "When these photons interact with each other, they're pushing against and deflect each other. The physics of what's happening in these molecules is similar to what we see in the movies."

 

To get the normally-massless photons to bind to each other, Lukin and colleagues, including Harvard post-doctoral fellow Ofer Fisterberg, former Harvard doctoral student Alexey Gorshkov and MIT graduate students Thibault Peyronel and Qiu Liang couldn't rely on something like the Force – they instead turned to a set of more extreme conditions.

 

Researchers began by pumped rubidium atoms into a vacuum chamber, then used lasers to cool the cloud of atoms to just a few degrees above absolute zero. Using extremely weak laser pulses, they then fired single photons into the cloud of atoms.

 

As the photons enter the cloud of cold atoms, Lukin said, its energy excites atoms along its path, causing the photon to slow dramatically. As the photon moves through the cloud, that energy is handed off from atom to atom, and eventually exits the cloud with the photon.

 

"When the photon exits the medium, its identity is preserved," Lukin said. "It's the same effect we see with refraction of light in a water glass. The light enters the water, it hands off part of its energy to the medium, and inside it exists as light and matter coupled together, but when it exits, it's still light. The process that takes place is the same it's just a bit more extreme – the light is slowed considerably, and a lot more energy is given away than during refraction."

 

When Lukin and colleagues fired two photons into the cloud, they were surprised to see them exit together, as a single molecule.

 

The reason they form the never-before-seen molecules?

 

An effect called a Rydberg blockade, Lukin said, which states that when an atom is excited, nearby atoms cannot be excited to the same degree. In practice, the effect means that as two photons enter the atomic cloud, the first excites an atom, but must move forward before the second photon can excite nearby atoms.

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Martian Top Soil Contains Two Percent Water

Martian Top Soil Contains Two Percent Water | Amazing Science | Scoop.it

NASA's Mars Science Laboratory rover Curiosity has found that the Mars topsoil is laced with surprisingly high quantities of water.

 

By now, we probably all know that there was once significant quantities of water on the Martian surface and, although the red planet is bone dry by terrestrial standards, water persists as ice just below the surface to this day.

Now, according to a series of new papers published in the journal Science, NASA’s Mars Science Laboratory rover Curiosity has found that the Mars topsoil is laced with surprisingly high quantities of the wet stuff.

 

“One of the most exciting results from this very first solid sample ingested by Curiosity is the high percentage of water in the soil,” said Laurie Leshin, Dean of Science at the Rensselaer Polytechnic Institute, N.Y., and lead author of one of the studies focusing on SAM analysis of Mars ‘fines.’ “About 2 percent of the soil on the surface of Mars is made up of water, which is a great resource, and interesting scientifically.”

 

Once scooped out of the ground by the rover’s robotic arm-mounted scoop (called the Collection and Handling for In-Situ Martian Rock Analysis, or, simply, CHIMRA), a small amount of the powder was sieved and dropped into SAM where it was heated to 835 degrees Celsius (1,535 degrees Fahrenheit). SAM then used its gas chromotograph, mass spectrometer and tunable laser spectrometer to identify the chemicals contained within the sample and the ratios of the different isotopes of elements contained within.

 

When heated, the instrument detected the abundance of water plus significant quantities of carbon dioxide, oxygen and sulfur compounds, according to the researchers. Carbonate materials — compounds that form in the presence of water — were also identified. The experiment confirmed the presence of oxygen- and chlorine-containing compounds — likely chlorates or perchlorates. Originally discovered by NASA’s 2008 Phoenix Mars Lander (and likely detected by NASA’s Viking landers in 1976), perchlorates were found in the soil of high-latitude arctic regions. This indicates that perchlorates occur globally over Mars.

 

 Though highly toxic to human biology, some microbes are known to use the oxidizing chemical for energy. This finding intensified the debate over whether hypothetical microbes on Mars could metabolize perchlorates in a similar way.

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