Delivering the capability to image nanostructures and chemical reactions down to nanometer resolution requires a new class of x-ray microscope that can perform precision microscopy experiments using ultra-bright x-rays from the National Synchrotron Light Source II (NSLS-II) at Brookhaven National Laboratory.
This groundbreaking instrument, designed to deliver a suite of unprecedented x-ray imaging capabilities for the Hard X-ray Nanoprobe (HXN) beamline, brings researchers one step closer to the ultimate goal of nanometer resolution at NSLS-II, a U.S. Department of Energy Office of Science User Facility.
The microscope manipulates novel nanofocusing optics called multilayer Laue lenses (MLL) — incredibly precise lenses grown one atomic layer at a time — which produce a tiny x-ray beam that is currently about 10 nanometers in size. Focusing an x-ray beam to that level means being able to see the structures on that length scale, whether they are proteins in a biological sample, or the inner workings of a fuel cell catalyst.
The team of scientists who built this microscope aren’t stopping there; they are working toward making the focused x-ray beam spot even smaller in the future. The microscope they developed produces x-ray images by scanning a sample while collecting various x-ray signals emerging from the sample. Analysis of these signals helps researchers understand crucial information about the materials they are examining: density, elemental composition, chemical state, and the crystalline structure of the sample.
Getting a clear image at this scale requires extremely high stability of the microscope to minimize vibrations and to reduce possible thermal drifts, changes in the microscope due to heat. It requires over twenty piezo motors — very fine motors that produce motion when electric currents are fed into piezo crystals — controlled down to nanometer-scale precision, crammed into a tight space about the size of a coffee maker, to meet its functionalities.
“This instrument incorporates most recent developments in interferometric sensing, nanoscale motion, and position control. Recorded drifts of two nanometers per hour are unprecedented and set a new benchmark for x-ray microscopy systems,” said Evgeny Nazaretski, a physicist at NSLS-II who spearheaded the development of the microscope.
After construction, the MLL module, a key component of the HXN x-ray microscope, was tested at the Diamond Light Source Beamline I-13L for extensive x-ray performance measurements. These measurements confirmed the stability and reliability of the new MLL system. Results are being published in the March issue of the Journal of Synchrotron Radiation.
Hanfei Yan, a co-author of the paper, added, “We are grateful to our collaborators from Argonne National Laboratory who shared their technical expertise from the beginning of this project and also to collaborators from the Diamond Light Source who wholeheartedly supported the x-ray experiments.”
“This instrument is a critical link connecting NSLS-II’s bright x-rays to unprecedented nanoscale x-ray imaging capabilities, which we believe will lead to many groundbreaking scientific discoveries”, stressed Yong Chu, the Group Leader of the Hard X-ray Nanoprobe Beamline at NSLS-II. The HXN beamline and the HXN x-ray microscope are currently being commissioned and will be available for user experiments later this year.
This work is published in the Journal of Synchrotron Radiation.
Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.
Dianne Depra, Tech Times | February 28, 10:37 AM
What drives movement in the city? Many things. A new study, however, found that a fifth of the movement in urban areas is social in nature, a finding that is evident in various cities.
In a study published in the journal Interface, researchers turned to anonymous phone data offering information that allowed for people’s social networks and locations to be reconstructed. By piecing together the information they had, the researchers were able to isolate networks as social- or work-oriented.
Jameson Toole from the Massachusetts Institute of Technology, one of the authors for the study, explained that they were able to determine how much of a city’s movement was social in nature by layering mobile and social data over the other.
By coming up with a way to quantify how much of urban movement is affected by social activity, researchers are of the belief that they have taken a step towards the creation of a new analytical aid that will be highly useful for policymakers and planners.
“If you are trying to estimate movement in a city and you don’t include the social component, your estimates are going to be off by about 20 percent,”stated Toole.
The study used data from three big cities in South America and Europe. By analyzing call locations, contact times and call networks, the researchers uncovered that there are essentially three social networks at play in cities: distant acquaintances, work colleagues and social companions. After quantifying activity from these networks, they concluded that primarily social movement represents up to 30 percent of total movement in the city.
In the study, the researchers detailed as well the building of an urban social movement model called “GeoSim.” It goes beyond previous urban mobility models by including a layer related to choices involving social activity. The GeoSim model fits data from the study better and may also be compared against other data in the future.
Experts say the study sheds new light on research on urban mobility, using two different kinds of data to establish relationship between two individuals. According to Esteban Moro from the Charles III University of Madrid, the study offers a quantitative grasp of how individuals manage tasks, time and interactions with a geographical context.
The study received funding support from the National Science Foundation, MIT’s Center for Complex Engineering Systems and the Accenture-MIT Alliance in Business Analytics. Other authors include Marta C. González, Christian M. Schneider, and Carlos Herrera-Yaqüe.
She captures the scene of an octopus in full flight leaping onto a crab, wrestling with it on the rocks and eventually pulling it under water.
The Guardian says that this is the first time that this behavior has ever been captured on video.
The paper also quotes Indrisie as saying,
” I didn’t know why I chose to film this crab, but thought I would try and get closer to it but something else beat me to it.” The video has attracted more than 7 million views on YouTube.
Down under, of course, all sorts of strange things go on. Here we have an octopus which can hunt on land. Is this an “Octo-croc” for Crocodile Dundee to hunt? It certainly has the aggression of a crocodile.
Among other interesting facts, Wiki informs us that an octopus actually has three hearts, but it doesn’t show any compassion in this encounter.
In the video, the cctopus is clearly more than ready for a scrap on the rocks with the crustacean critter. It’s certainly a tenacious fighter and appears to be no match for the crab.
What the outcome of the brawl under water is can’t be seen, so we’re left wondering if tentacles beat claws.
Apparently, an octopus has a hard beak, but when it captures its prey it first injects it with paralyzing saliva. After poisoning a crab, it then breaks it up into small edible pieces.
Indrisie, who aptly works as a seafood assistant, is quoted by the Independent as saying,
“We hung around for a while, but I understand octopus flip it open and eat it pretty quick, so I knew it was toast.”
It seems that “Jumping- Jack- Flash- the octopus” isn’t so rare and octopuses frequently like to make a land grab, or in this instance, a land crab.
According to a source close to the matter, Fitbit is evaluating a purchase of FitStar for upwards of $25 to $40 million in a mix of cash and stock. A deal like this could always fall apart, of course, but if it goes through our source says the acquisition could close as early as next week.
Fitbit is one of the oldest and has some of the most popular activity trackers on the market. Founded in 2007, its devices accounted for approximately 50 percent of all wearable bands sold in 2013, according to one research report.
That said, the market has been flooded with a ton of new fitness tracking gadgets in the last year or two. Jawbone, Misfit, Mio, Basis, Garmin, and even Microsoft have released competing products. And that’s not even counting the upcoming Apple Watch, which the companyreportedly expects to sell 5 million of during its initial run.
Fitbit’s hardware includes a variety of wristbands, clip-on activity trackers, and a connected scale. It also has mobile apps and an online dashboard through which customers can log their steps, weight, food intake, and other workout activities.
While Fitbit’s software provides an all-in-one platform for tracking all that data, it also recognizes not everyone will want to use its apps for all those functions. As a result, it’s partnered to share data with a number of third-party app makers, such as LoseIt!, MyFitnessPal, MapMyRun, Endomondo, and also FitStar.
Fitbit’s decision to pursue an acquisition of FitStar makes sense as the activity tracker market matures and more consumers are looking for practical applications that could help them get fit. That is, now that they have they data, what can they actually do with it?
FitStar makes a series of fitness and yoga apps that provide personalized workout programs for users. Those apps include high-quality video workouts led by celebrity fitness trainers to help motivate users to get in shape. Over time, its apps track the exercises users take part in and adapts to their strengths (and weaknesses).
The purchase has a number of benefits for each company. Beyond the obvious cross-pollination between Fitbit and FitStar user bases — i.e. Fitbit pushing its users to join FitStar and vice versa — an acquisition would give Fitbit an entree into the growing online fitness instruction market, while providing more resources for FitStar to continue producing instructional videos.
All of that is important as Fitbit pursues an IPO, which is reportedly planned for later this year. It would also make Fitbit’s platform a bit more defensible against “dumb trackers” that only provide analytics without actually helping users to get off the couch.
A small side benefit to this is an incremental revenue stream that would come from FitStar’s premium subscription user base and sales of individual workout programs on its apps.
Finally, the acquisition could be an integral part of Fitbit’s defense against the Apple Watch — a device which any number of fitness startups will soon begin making workout apps for. Fitbit is one of the few wearable manufacturers not to integrate with Apple’s HealthKit, due to competitive concerns around the release of the Apple Watch. We’ve heard that’s one reason why Fitbit devices were pulled from the Apple store late last year.
Representatives from Fitbit and FitStar did not respond to our request for comment.
MATT ROBINSON, VANCOUVER SUN
A B.C. company that created an apple genetically engineered not to turn brown has been bought by a U.S. corporation for $41 million in stocks and cash.
Okanagan Specialty Fruits Inc. of Summerland, B.C., was acquired by Intrexon Corporation in a conditional deal announced in a Friday news release.
Okanagan had its Arctic apples, which retain their colour after being exposed to air, approved for sale by the U.S. Department of Agriculture earlier this month.
Thomas R. Kasser, the senior vice-president of Intrexon’s food sector, said the B.C. company had “potential to revolutionize the tree fruit industry.
Neal Carter, the founder of Okanagan Specialty Fruits, will stay on with the company after the deal closes, said Kasser.
“We are committed to bringing better versions of consumers’ favourite fruits to their grocery stores and kitchens, while addressing additional novel traits in tree fruits that reduce waste and address supply chain challenges,” said Carter.
Okanagan was founded in 1996 and uses biotechnology to develop different varieties of fruit.
Carter recently stated that he expects golden and granny varieties of the non-browning apple to be available on U.S. grocery shelves by late 2016.
February 27, 2015
A prototype “quantum radar” that has the potential to detect objects that are invisible to conventional systems has been developed by an international research team led by a quantum information scientist at the University of York.
The new breed of radar is a hybrid system that uses quantum correlation between microwave and optical beams to detect objects of low reflectivity such as cancer cells or aircraft with a stealth capability. Because the quantum radar operates at much lower energies than conventional systems, it has the long-term potential for a range of applications in biomedicine, including non-invasive nuclear magnetic resonance (NMR) scans.
The idea is to use “quantum illumination” to “interrogate the target region with one optical beam while retaining its entangled counterpart for subsequent joint measurement with the light returned from that target region,” the researchers explain in a paper in Physical Review Letters.
Quantum illumination has only been demonstrated at optical wavelengths, but the research team, led by Stefano Pirandola of the University’s Department of Computer Science and the York Centre for Quantum Technologies, found that a special converter — a double-cavity device that couples the microwave beam to an optical beam using a nano-mechanical oscillator — was the key to enabling the concept to work at microwave frequencies.
The device can either generate microwave-optical entanglement (during signal emission) or convert a microwave signal into an optical beam (during the collection of the reflection beams from the object).
Detecting invisible objects in noisy environments
A conventional radar antenna emits a microwave signal to scan a region of space. Any target object would reflect the signal to the source but objects of low reflectivity immersed in regions with high background noise are difficult to spot using classical radar systems. In contrast, quantum radars exploit quantum entanglement to enhance their sensitivity to detect small signal reflections from very noisy regions.
Pirandola said that while practical quantum radars were some way off, they would have superior performance especially at the low-photon regime. “Such a non-invasive property is particularly important for short-range biomedical applications. In the long term, the scheme could be operated at short distances to detect the presence of defects in biological samples or human tissues in a completely non-invasive fashion, thanks to the use of a low number of quantum-correlated photons.
“Our method could be used to develop non-invasive NMR spectroscopy of fragile proteins and nucleic acids. In medicine, these techniques could potentially be applied to magnetic resonance imaging, with the aim of reducing the radiation dose absorbed by patients.”
Pirandola was funded by the Leverhulme Trust and the Engineering and Physical Sciences Research Council.
February 27, 2015
USC scientists may have discovered a family of superconductor materials called superatoms that could lead to room-temperature supercomputers.
A team led by Vitaly Kresin, professor of physics at the USC Dornsife College of Letters, Arts and Sciences, found that aluminum “superatoms” — homogenous clusters of atoms — appear to form Cooper pairs of electrons (one of the key elements of superconductivity) at temperatures around 100 Kelvin.
Though 100 Kelvin is about -280 degrees Fahrenheit — not quite room temperature, it’s a significant increase compared to bulk aluminum metal, which turns superconductive only near 1 Kelvin (-457 degrees Fahrenheit).
“This may be the discovery of a new family of superconductors, and raises the possibility that other types of superatoms will be capable of superconductivity at even warmer temperatures,” said Kresin, corresponding author of a paper on the finding published by Nano Letters on Jan. 28.
Superconductivity is the ability to transmit electricity without any resistance, meaning that no energy is lost in the transmission. Superconductors operating at extremely low temperatures are already used for MRI machines, powerful electromagnets that levitate maglev trains, particle accelerators, and ultrasensitive magnetic field sensors, but a room-temperature superconductor would allow engineers to make all electronic devices ultra-efficient.
Superconductivity with superatoms
When electrons flow through a material, they bump into various imperfections that knock them off course. That’s the resistance that causes energy loss in the form of heat. If the electrons are mated up into Cooper pairs, however, that connection is just strong enough to keep them on course regardless of what they bump into. Cooper pairs are what make superconductivity work.
Kresin envisions a future in which electronic circuits could be built by placing superatoms in a chain along a substrate material, allowing electricity to flow unhindered along the chain.
The research was supported by the National Science Foundation.
February 27, 2015
A small area of the brain called the anterior cingulate cortex (ACC) in the thalamus can be optically stimulated to control pain, University of Texas at Arlington scientists have found.
The researchers used optogenetic stimulation with a blue laser to control pain sensation in a mouse, created by a chemical irritant (formalin) and mechanical pain, such as that experienced following a pinprick or pinch.
“Our results clearly demonstrate, for the first time, that optogenetic stimulation of inhibitory neurons in ACC leads to decreased neuronal activity and a dramatic reduction of pain behavior,”said Samarendra Mohanty, an assistant professor of physics who leads the Biophysics and Physiology Lab in the UT Arlington College of Science and co-author on an open-access paper published online Wednesday Feb. 25 by the journal PLOS ONE.
Other researchers have previously experimented with using electrodes to stimulate inhibitory neurons (to reduce pain) in the ACC, but such stimulation lacks specificity and leads to activation of both excitatory and inhibitory neurons, he said.
Mohanty suggested that the results could lead to increased understanding of pain pathways and strategies for managing chronic pain, which often leads to severe impairment of normal psychological and physical functions.
However, “while reducing the sensation for chronic pain by optical stimulation, we still want to sense certain types of pain because they tell us to move our hands or legs away from something that is too hot or that might otherwise hurt us if we get too close,” Mohanty noted.
The team now plans to carry out localized non-invasive stimulation of small brain regions such as the ACC to better understand and control pain.
UT Dallas and University of Kentucky researchers also participated in the study. Mohanty’s lab is currently supported by a $384,269 two-year grant from the National Institutes of Health National Institute of Neurological Disorders and Strokes.
Feb 27, 2015, SYDNEY LUPKIN