Using a single molecule to create a new magnetic field sensor

 

Fri, 01/30/2015 - 9:16am Univ. of Liverpool   Scanning tunneling microscope (STM) image of iron phtalocyanine.Researchers at the Univ. of Liverpool and Univ. College London (UCL) have shown a new way to use a single molecule as a magnetic field sensor. In a study, published in Nature Nanotechnology, the team shows how magnetism can manipulate the way electricity flows through a single molecule, a key step that could enable the development of magnetic field sensors for hard drives that are a tiny fraction of their present size. In hard drives, magnetized areas on spinning disks are used to store information. As the magnetized areas pass a magnetic sensor, they trigger fluctuations in electric current flowing through the sensor, allowing the data to be read. Making these areas smaller increases a hard drive's storage capacity without making it bigger, but also requires a smaller sensor. Fadi El Hallak, a researcher at UCL who conceived of the study and now works for Seagate Technology, said: "Making smaller sensors isn't trivial. It is difficult to use magnetism to control the current flowing through objects the size of single molecules because the response to changes in the magnetic field is often very weak." To get around this problem, the researchers developed a method of magnifying the effect of the magnetism on the flow of current in the detector. Mechanical tunneling First, they created a junction in which a single magnetic molecule was weakly coupled to two metallic leads. The barriers between the molecule and the nearby metals were high enough that electrical charge in the metals could not flow over the barriers. However, a small fraction of the electrons can effectively go through the barriers by undergoing quantum mechanical tunneling, which enables a tiny current to flow through the molecule when a voltage is applied across it. The scientists configured the junction so that the molecule was much more strongly connected to one metal lead than the other. The effect of the magnetic field on the tunneling current is then leveraged and greatly enhanced. Dr. Mats Persson, from the Univ. of Liverpool's Dept. of Chemistry, said: "This research demonstrates a new kind of single molecule sensor for magnetic fields, which is promising for creating new computer technologies." Source: Univ. of Liverpool

DNA nanoswitches reveal how life’s molecules connect

 

Fri, 01/30/2015 - 8:17am Kat J. McAlpine, Wyss Institute for Biologically Inspired Engineering Gel electrophoresis, a common laboratory process, sorts DNA or other small proteins by size and shape using electrical currents to move molecules through small pores in gel. The process can be combined with novel DNA nanoswitches, developed by Wyss Associate Faculty member Wesley Wong, to allow for the simple and inexpensive investigation of life's most powerful molecular interactions. Image: Wyss Institute at Harvard Univ. A complex interplay of molecular components governs almost all aspects of biological sciences—healthy organism development, disease progression and drug efficacy are all dependent on the way life's molecules interact in the body. Understanding these biomolecular interactions is critical for the discovery of new, more effective therapeutics and diagnostics to treat cancer and other diseases, but currently requires scientists to have access to expensive and elaborate laboratory equipment. Now, a new approach developed by researchers at the Wyss Institute for Biologically Inspired Engineering, Boston Children's Hospital and Harvard Medical School promises a much faster and more affordable way to examine biomolecular behavior, opening the door for scientists in virtually any laboratory world–wide to join the quest for creating better drugs. The findings are published in Nature Methods. "Biomolecular interaction analysis, a cornerstone of biomedical research, is traditionally accomplished using equipment that can cost hundreds of thousands of dollars," said Wyss Associate Faculty member Wesley P. Wong, PhD, senior author of study. "Rather than develop a new instrument, we've created a nanoscale tool made from strands of DNA that can detect and report how molecules behave, enabling biological measurements to be made by almost anyone, using only common and inexpensive laboratory reagents." Wong, who is also assistant professor at Harvard Medical School in the Depts. of Biological Chemistry & Molecular Pharmacology and Pediatrics and Investigator at the Program in Cellular and Molecular Medicine at Boston Children's Hospital, calls the new tools DNA "nanoswitches". Nanoswitches comprise strands of DNA onto which molecules of interest can be strategically attached at various locations along the strand. Interactions between these molecules, such as successful binding of a drug compound with its intended target, such as a protein receptor on a cancer cell, cause the shape of the DNA strand to change from an open and linear shape to a closed loop. Wong and his team can easily separate and measure the ratio of open DNA nanoswitches vs. their closed counterparts through gel electrophoresis, a simple lab procedure already in use in most laboratories, that uses electrical currents to push DNA strands through small pores in a gel, sorting them based on their shape. "Our DNA nanoswitches dramatically lower barriers to making traditionally complex measurements," said co–first author Ken Halvorsen, formerly of the Wyss Institute and currently a scientist at the RNA Institute at Univ. of Albany. "All of these supplies are commonly available and the experiments can be performed for pennies per sample, which is a staggering comparison to the cost of conventional equipment used to test biomolecular interactions." To encourage adoption of this method, Wong and his team are offering free materials to colleagues who would like to try using their DNA nanoswitches. "We've not only created starter kits but have outlined a step–by–step protocol to allow others to immediately implement this method for research in their own labs, or classrooms," said co–first author Mounir Koussa, a graduate candidate in neurobiology at Harvard Medical School. "Wesley and his team are committed to making an impact on the way bio–molecular research is done at a fundamental level, as is evidenced by their efforts to make this technology accessible to labs everywhere," said Wyss Institute Founding Director Donald Ingber, MD, PhD, who is also the Judah Folkman Professor of Vascular Biology at Boston Children's Hospital and Harvard Medical School and a Professor of Bioengineering at Harvard SEAS. "Biomedical researchers all over the world can start using this new method right away to investigate how biological compounds interact with their targets, using commonly available supplies at very low cost." Source: Wyss Institute for Biologically Inspired Engineering at Harvard Univ.

Objetos comuns fotografados em superzoom revelam um novo universo de detalhes

 

Objetos fotografados em Super-Zoom

 

Fonte : Gizmodo Brasil

OpenBiome will pay for poo

 

If you think your better half buys a lot of crap, then you might want to consider OpenBiome before starting on the criticism. The American non-profit is paying donors dollars for their doo-doo in an effort to gather more materials for fecal microbiota transplants (FMTs), a relatively new, but 90 percent effective, treatment for the debilitating Clostridium difficile infection (CDI). Clostridium difficile (C.difficile) are a bacteria found in the soil, air, water, and human and animal feces. Although many can carry the bacteria and suffer no ill effects, others will experience severe diarrhea, abdominal pain and fever. More extreme cases can require hospitalization and perhaps even lead to death. OpenBiome claims that between 14,000 and 30,000 deaths are estimated to be caused by CDI each year in the US alone. While healthy people are unlikely to develop CDI, those taking antibiotics are at higher risk of picking up cases of C.difficile from infected surfaces. This is because antibiotics kill good as well as bad bacteria in the gastrointestinal tract, providing a site for the bacteria to gain a foothold. According to the Mayo Clinic, the number of cases have increased rapidly over the past two decades, with the elderly who take antibiotics being particularly prone. Though ceasing the antibiotic used to treat the primary infection will generally be effective on treating mild CDI cases, more targeted antibiotic treatment is the standard procedure for more serious cases. However, the Centers for Disease Control now says that fecal transplants appear to be the most effective method for helping patients with repeat C. difficile infections. The US Food and Drug Administration has also classified FTM as an "investigational drug" and since the middle of 2013 it has allowed doctors to treat patients with C.difficile without their having to make the usual Investigational New Drug application. The problem, however, is that even as acceptance for fecal transplants grows – the Mayo Clinic began performing them in 2011 – the amount of fecal matter available does not. Typically it is close relations who provide the material. The OpenBiome team says they founded their non-profit, “after watching a friend and family member suffer through 18 months of C. difficile and 7 rounds of vancomycin before finally receiving a successful, life-changing Fecal Microbiota Transplantation (FMT)." After seeing the difficulty of securing the treatment first hand, they realized that expanded access was key. We have written about less-traditional uses of FMT before, though in the case of Dr Jeff Leach he was researching gut bacteria and the hunter-gatherer diet, rather than treating a stubborn case of C.difficile. But why does this work? The importance lies in gut flora and healthy gut bacteria. Scientists and medical professionals are beginning to understand that the key to many diseases and even allergies may lie in what lives in people’s guts. In fact, "hereditary gut bacteria" may play a role even in obesity, with researchers at Kings College London and Cornell University examining the potential of probiotic treatments for the obese. FMT involves introducing the stool containing microbes that include bacteria, fungi and viruses from a healthy donor into the gut of the person suffering a C. difficile infection. This is performed more or less in the way one would (or try not to) imagine: via colonoscopic or nasogastric administration – the latter refers to a tube inserted into the nose or mouth and down the throat. OpenBiome is seeking healthy donors who will be are financially remunerated at US$40 per sample, with those donating five times each week pocketing an extra $50. However, all donations must be done on-site at their Massachusetts suite and all donors go through a lengthy screening process and are rescreened each 60 days. Donors can also win prizes for the "biggest single donation of the month" or the most donations. According to the non-profit, less than 20 percent of people screened go on to become donors. For those on the receiving end, as a non-profit, the company charges $250 per treatment to cover its costs. Synthetic stool For those worried about what Scientific American termed the "ick factor" surrounding FMT, a synthetic stool sample, called "rePOOPulate," was developed last year for the treatment of C. difficile with the results published in the journal Microbiome in 2013. "Patient concerns" is the way both the rePOOPulate developers and those at OpenBiome describe said “ick” factor inherent in discussions of FMT. OpenBiome is also working to develop a synthetic alternative, partnering with Assembly Biosciences in researching and product supply. “[We] believe that supporting these research efforts will be critical to improving treatment options," says the company.   Source: OpenBiome

New Portable Vacuum Standard

 

January 23, 2015 Contact: Jacob Ricker (301) 975-4475 The PVS is housed within the white “igloo” enclosure at left. At right is an auxiliary vacuum system used for pressure calibrations. A novel Portable Vacuum Standard (PVS) has been added to the roster of NIST’s Standard Reference Instruments (SRI). It is now available for purchase as part of NIST’s ongoing commitment to disseminate measurement standards and thereby reduce the need for the expensive and time-consuming process of transporting customer instruments to NIST for calibration. The PVS is a compact, high-accuracy, low-pressure/vacuum laboratory standard that is calibrated directly against the primary standard at NIST. It enables high-precision calibrations, measurements, or inter-laboratory comparisons (ILC) at a customer’s facility. It can be used as a direct replacement for a commercial mercury manometer, while offering similar or better uncertainties and lower cost of ownership. The PVS package is also more rugged and does not contain mercury – a significant safety issue for the common high-accuracy manometers that it replaces. Many customers do not have the technical expertise to build their own standards or only need a standard for a short period of time, such as during an ILC. For about $100,000 per unit (depending on specifications and configuration), the PVS can meet those needs. NIST will provide the relevant calibration reports and method for analyzing the measurements. The latest version of the standard, which has been under development for more than a decade by scientists in NIST's Thermodynamic Metrology Group, enables pressure measurements from 1 Pa to 130,000 Pa. (Air pressure at sea level is about 101,325 Pa.) It is possible to extend the instrument’s range to 370,000 Pa as needed. The PVS combines two different kinds of low-pressure sensors enclosed in an insulated container the size of a suitcase that maintains a constant internal temperature to within 5 mK. The first is a resonance silicon gauge (RSG) that monitors two capacitance diaphragm gauges (CDGs). RSGs are microelectromechanical systems (MEMS) that measure the effect of pressure- induced strain on the resonant frequency of a silicon oscillator. CDGs measure pressure-induced changes in the position of an alloy diaphragm that serves as one plate of a capacitor, and are the workhorse sensors for most high-precision vacuum operations. Combining the two, says project scientist Jay Hendricks, brings unique benefits: "CDGs have extremely fine resolution at low pressure. RSGs have outstanding long-term drift stability—in the range of 0.01%, which is a factor of 10 better than the CDGs. So to get the best of both, we use an RSG to calibrate the CDGs.” Contact: Jacob Ricker, (301) 975-4475. Any mention or image of commercial products within NIST web pages is for information only; it does not imply recommendation or endorsement by NIST.

Potential new drug for lung cancer

 

Potential new drug target for lung cancer

Neutron beams reveal how two potential pieces of Parkinson’s puzzle fit

 

Thu, 01/29/2015 - 11:44am Chad Boutin, NIST The proteins GCase (in pink) and α-syn (blue) forms a complex in cellular membrane. Neutron reflectometry (suggested by the yellow beam) revealed the structure of the complex. α-Syn shifts GCase slightly away from membrane, possibly contributing to effects related to Parkinson’s disease. Image: Alan Hoofring/NIH Medical ArtsTo understand diseases like Parkinson’s, the tiniest of puzzles may hold big answers. That’s why a team including scientists from NIST have determined how two potentially key pieces of the Parkinson’s puzzle fit together, in an effort to reveal how the still poorly understood illness develops and affects its victims. This puzzle is a tough one because its pieces are not only microscopic but 3-D, and can even change shape. The pieces are protein molecules whose lengthy names are abbreviated as GCase and α-syn. The two proteins wrap around each other and take on a complicated shape before attaching themselves to the membrane surface inside a neural cell in a victim’s brain.  While much remains unknown about Parkinson’s, clues abound that the proteins’ behavior is somehow important. Parkinson’s victims have a buildup of α-syn in their cells, a possible factor in the dementia that the disease often brings. They also are far more likely to have a mutation in the gene that instructs cells to create GCase. Low levels of GCase cause another disease, Gaucher, and in some individuals suffering from both Parkinson’s and Gaucher simultaneously, Parkinson’s may appear at a younger age.  To get a better handle on how these proteins operate in the body, the team—which also included scientists from the National Institutes of Health (NIH) and Carnegie Mellon Univ.—came to the NIST Center for Neutron Research (NCNR) to get a picture of how the two proteins combine into a single unit called a complex that interacts with cell membranes. Using techniques including neutron reflectometry, the team teased out the first-ever structural picture of the GCase/α-syn complex, including their shape change, which NIH’s Jennifer Lee says would not have been detectable by any other methods.  “It gives us a potential interaction model of the two and structural insights in how α-syn may interfere with activity on a cell membrane,” Lee says. “An equally important contribution here is that this is the first, I believe, to look at complex formation at the membrane interface using neutron science.”  The study still leaves many mysteries about the complex—notably how it attaches to and interacts with the membrane inside a part of the cell called the lysosome where α-syn is broken-down. The team plans to follow up with additional investigations, especially once an improved reflectometer that could offer greater resolution arrives at the NCNR in about 2017. Meanwhile, the results of the current study—and the tools that provided them—will give the team other options to explore.  “It lays the groundwork for exploring the complex relationship between proteins that are involved in the causes of disease,” Lee says. “This will also offer a way for us to investigate other substances that would affect the interaction.” Source: NIST

10 cool Psychology Jobs

 

10 Psychology Jobs

Psychological disorders

 

List of psychological disorders

Extreme oxygen loss in oceans accompanied past global climate change

 

Thu, 01/29/2015 - 11:58am Kat Kerlin, UC Davis News Service Seafloor sediment cores reveal abrupt, extensive loss of oxygen in the ocean when ice sheets melted roughly 10,000 to 17,000 years ago, according to a study from the Univ. of California, Davis. The findings provide insight into similar changes observed in the ocean today. In the study, published in PLOS ONE, researchers analyzed marine sediment cores from different world regions to document the extent to which low oxygen zones in the ocean have expanded in the past, due to climate change. From the subarctic Pacific to the Chilean margins, they found evidence of extreme oxygen loss stretching from the upper ocean to about 3,000 m deep. In some oceanic regions, such loss took place over a time period of 100 years or less. “This is a global story that knits these regions together and shows that when you warm the planet rapidly, whole ocean basins can lose oxygen very abruptly and very extensively,” said lead author Sarah Moffitt, a postdoctoral scholar with the UC Davis Bodega Marine Laboratory and formerly a graduate student with the Graduate Group in Ecology.  Marine organisms, from salmon and sardines to crab and oysters, depend on oxygen to exist. Adapting to an ocean environment with rapidly dropping oxygen levels would require a major reorganization of living things and their habitats, much as today polar species on land are retreating to higher, cooler latitudes. The researchers chose the deglaciation period because it was a time of rising global temperatures, atmospheric carbon dioxide and sea levels—many of the global climate change signs the Earth is experiencing now. “Our modern ocean is moving into a state that has no precedent in human history,” Moffitt said. “The potential for our oceans to look very, very different in 100 to 150 years is real. How do you use the best available science to care for these critical resources in the future? Resource managers and conservationists can use science like this to guide a thoughtful, precautionary approach to environmental management.” Source: Univ. of California, Davis

Missing link in metal physics explains Earth’s magnetic field

 

Thu, 01/29/2015 - 9:58am Carnegie Institute Conception of Earth’s core overlaid by the electronic structure of iron; the width (fuzziness) of the lines results from the electron-electron scattering. Image: Ronald CohenEarth’s magnetic field is crucial for our existence, as it shields the life on our planet’s surface from deadly cosmic rays. It is generated by turbulent motions of liquid iron in Earth’s core. Iron is a metal, which means it can easily conduct a flow of electrons that makes up an electric current. New findings from a team including Carnegie Institute’s Ronald Cohen and Peng Zhang shows that a missing piece of the traditional theory explaining why metals become less conductive when they are heated was needed to complete the puzzle that explains this field-generating process. Their work is published in Nature. The center of the Earth is very hot, and the flow of heat from the planet’s center towards the surface is thought to drive most of the dynamics of the Earth, ranging from volcanoes to plate tectonics. It has long been thought that heat flow drives what is called thermal convection—the hottest liquid becomes less dense and rises, as the cooler, more-dense liquid sinks—in Earth’s liquid iron core and generates Earth’s magnetic field. But recent calculations called this theory into question, launching new quests for its explanation. In their work, Cohen and Zhang, along with Kristjan Haule of Rutgers Univ., used a new computational physics method and found that the original thermal convection theory was right all along. Their conclusion hinges on discovering that the classic theory of metals developed in the 1930’s was incomplete. The electrons in metals, such as the iron in Earth’s core, carry current and heat. A material’s resistivity impedes this flow. The classic theory of metals explains that resistivity increases with temperature, due to atoms vibrating more as the heat rises. The theory says that at high temperatures resistivity happens when electrons in the current bounce off of vibrating atoms. These bounced electrons scatter and resist the current flow. As temperature increases, the atoms vibrate more, and increasing the scattering of bounced electrons. The electrons not only carry charge, but also carry energy, so that thermal conductivity is proportional to the electrical conductivity. The work that had purportedly thrown the decades-old prevailing theory on the generation of Earth’s magnetic field out the window claimed that thermal convection could not drive magnetic-field generation. The calculations in those studies said that the resistivity of the molten metal in Earth’s core, which is generated by this electron scattering process, would be too low, and thus the thermal conductivity too high, to allow thermal convection to generate the magnetic field. Cohen, Zhang and Haule’s new work shows that the cause of about half of the resistivity generated was long neglected: it arises from electrons scattering off of each other, rather than off of atomic vibrations. “We uncovered an effect that had been hiding in plain sight for 80 years,” Cohen said. “And now the original dynamo theory works after all.” Source: Carnegie Institute

NASA, Boeing and SpaceX outline future of commercial manned spaceflight

 

NASA's Stephanie Schierholz introduces the panel of NASA and commercial representatives (Photo: NASA TV) Image Gallery (4 images) For several years, NASA and its private enterprise partners have been working on the space agency's Commercial Crew Program (CCP) to provide an astronaut ferry service from US soil to the International Space Station (ISS). Now a panel from NASA, Boeing, and SpaceX has outlined the latest timetable leading up to the first commercial flights. The two companies were selected last year by NASA to develop privately owned and operated US spacecraft to ferry crews to the ISS.. When certified, the Boeing CST-100 and SpaceXDragon V.2 (AKA Crew Dragon) will be able to travel to and from the ISS carrying up to seven passengers or a mixture of passengers and cargo. Being capable of remaining on station for 210 days, they will double as lifeboats; allowing ISS crews to expand to seven people. According to NASA, the extra crew will allow the time available for scientific experiments to grow from 40 to 80 hours per week. When fully deployed, Boeing and SpaceX will provide NASA with two independent systems for sending astronauts back and forth from the ISS. However, unlike during the Space race when companies would develop spacecraft in conjunction with NASA, which the latter would operate, the two companies retain ownership of the craft and are responsible for the development, launching, and operation of the vehicles, boosters, and recovery systems. On Monday, NASA and its partners outlined the next phases of the CCP. Boeing will continue development of its manned capsule with a pad abort test scheduled for February 2017, an unmanned flight test in April 2017, and then a flight with a Boeing test pilot and a NASA astronaut in July 2017. Meanwhile, SpaceX has announced a pad abort test for next month, with an in-flight abort test later this year, an unmanned flight test in late 2016, and a manned flight test in early 2017. During this process, NASA says that it is providing oversight to make certain that the two systems meet stringent safety standards, as well as the use of launch facilities at the Kennedy Space Center and the Cape Canaveral Air Force Station. Source: NASA

Sprayable Sleep looks to spray away insomnia

 

Just a couple of sprays before bed allows the melatonin formula to soak into the skin Image Gallery (4 images) A little more than a year ago, Gizmag featured an Indiegogo campaign that was marketing Sprayable Energy, which delivered a caffeine hit through the skin. Now the same company, Sprayable, has launched another campaign for a spray claimed to do the opposite – it puts you to sleep. Gizmag got a sample of Sprayable Sleep to put these claims to the test. Sprayable Sleep utilizes melatonin, which is a chemical that humans produce naturally to control our night-day cycle. According to the company, current oral melatonin pills, which are a common administration for aiding sleep, often contain 10 to 100 times more of the chemical than is necessary. Sprayable uses a fraction of the sleep-inducing juice, which the company claims will enter the body "gently and smoothly" over time as it gradually permeates the skin. While overdosing on melatonin is incredibly unlikely, even in oral use, the company still has a disclaimer saying, "do not exceed 8 sprays in 24 hours." "It definitely does run the risk of being a little too effective for some people," says Ben Yu, one of the co-founders of Sprayable. "Since it absorbs steadily through the skin, some people have reported that despite sleeping really well, they end up needing more sleep than they planned for, and consequently when they force themselves awake before their bodies are ready to wake up with an alarm clock, they do still feel a little groggy.” The difference, as the company sees it, is that Sprayable Sleep emulates the body’s natural melatonin production, bypassing the digestive system and making the application more natural than taking the chemical in pill form. The initial application was a bit off-putting for me, as I'm not generally accustomed to sprays or colognes, but after the initial wince of uncertainty, the application process was smooth. I was pleasantly surprised that there was no stickiness to the formula, and the company claims it is odorless as well. While this was mostly true, there was a light, new-car-esque smell, though this may have been from manufacturing rather than the formula itself. Application is recommended either on each side of the neck or each wrist an hour before bed. While this writer only experienced mildly-heavy eyes after administration, my wife was out within twenty minutes. There was little odor and the mist was easy to apply. This method of application certainly feels more natural than pills, but as can be expected, results will vary. One bottle costs US$15, and contains enough of the insomnia killer to last one month. Sprayable Sleep already has over US$125,000 raised on the Indiegogo campaign, with 31 days still to go. If it keeps this pace, Sprayable Sleep will leave its predecessor in its wake.   Source: Sprayable