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  • richardmitnick 7:56 am on May 14, 2015 Permalink | Reply
    Tags: , , , Microscopy, , ,   

    From MIT: “Researchers build new fermion microscope” 


    MIT News

    May 13, 2015
    Jennifer Chu

    1
    Graduate student Lawrence Cheuk adjusts the optics setup for laser cooling of sodium atoms. Photo: Jose-Luis Olivares/MIT

    2
    Laser beams are precisely aligned before being sent into the vacuum chamber. Photo: Jose-Luis Olivares/MIT

    3
    Sodium atoms diffuse out of an oven to form an atomic beam, which is then slowed and trapped using laser light. Photo: Jose-Luis Olivares/MIT

    4
    A Quantum gas microscope for fermionic atoms. The atoms, potassium-40, are cooled during imaging by laser light, allowing thousands of photons to be collected by the microscope. Credit: Lawrence Cheuk/MIT

    5
    The Fermi gas microscope group: (from left) graduate students Katherine Lawrence and Melih Okan, postdoc Thomas Lompe, graduate student Matt Nichols, Professor Martin Zwierlein, and graduate student Lawrence Cheuk. Photo: Jose-Luis Olivares/MIT

    Instrument freezes and images 1,000 individual fermionic atoms at once.

    Fermions are the building blocks of matter, interacting in a multitude of permutations to give rise to the elements of the periodic table. Without fermions, the physical world would not exist.

    Examples of fermions are electrons, protons, neutrons, quarks, and atoms consisting of an odd number of these elementary particles. Because of their fermionic nature, electrons and nuclear matter are difficult to understand theoretically, so researchers are trying to use ultracold gases of fermionic atoms as stand-ins for other fermions.

    But atoms are extremely sensitive to light: When a single photon hits an atom, it can knock the particle out of place — an effect that has made imaging individual fermionic atoms devilishly hard.

    Now a team of MIT physicists has built a microscope that is able to see up to 1,000 individual fermionic atoms. The researchers devised a laser-based technique to trap and freeze fermions in place, and image the particles simultaneously.

    The new imaging technique uses two laser beams trained on a cloud of fermionic atoms in an optical lattice. The two beams, each of a different wavelength, cool the cloud, causing individual fermions to drop down an energy level, eventually bringing them to their lowest energy states — cool and stable enough to stay in place. At the same time, each fermion releases light, which is captured by the microscope and used to image the fermion’s exact position in the lattice — to an accuracy better than the wavelength of light.

    With the new technique, the researchers are able to cool and image over 95 percent of the fermionic atoms making up a cloud of potassium gas. Martin Zwierlein, a professor of physics at MIT, says an intriguing result from the technique appears to be that it can keep fermions cold even after imaging.

    “That means I know where they are, and I can maybe move them around with a little tweezer to any location, and arrange them in any pattern I’d like,” Zwierlein says.

    Zwierlein and his colleagues, including first author and graduate student Lawrence Cheuk, have published their results today in the journal Physical Review Letters.

    Seeing fermions from bosons

    For the past two decades, experimental physicists have studied ultracold atomic gases of the two classes of particles: fermions and bosons — particles such as photons that, unlike fermions, can occupy the same quantum state in limitless numbers. In 2009, physicist Marcus Greiner at Harvard University devised a microscope that successfully imaged individual bosons in a tightly spaced optical lattice. This milestone was followed, in 2010, by a second boson microscope, developed by Immanuel Bloch’s group at the Max Planck Institute of Quantum Optics.

    These microscopes revealed, in unprecedented detail, the behavior of bosons under strong interactions. However, no one had yet developed a comparable microscope for fermionic atoms.

    “We wanted to do what these groups had done for bosons, but for fermions,” Zwierlein says. “And it turned out it was much harder for fermions, because the atoms we use are not so easily cooled. So we had to find a new way to cool them while looking at them.”

    Techniques to cool atoms ever closer to absolute zero have been devised in recent decades. Carl Wieman, Eric Cornell, and MIT’s Wolfgang Ketterle were able to achieve Bose-Einstein condensation in 1995, a milestone for which they were awarded the 2001 Nobel Prize in physics. Other techniques include a process using lasers to cool atoms from 300 degrees Celsius to a few ten-thousandths of a degree above absolute zero.

    A clever cooling technique

    And yet, to see individual fermionic atoms, the particles need to be cooled further still. To do this, Zwierlein’s group created an optical lattice using laser beams, forming a structure resembling an egg carton, each well of which could potentially trap a single fermion. Through various stages of laser cooling, magnetic trapping, and further evaporative cooling of the gas, the atoms were prepared at temperatures just above absolute zero — cold enough for individual fermions to settle onto the underlying optical lattice. The team placed the lattice a mere 7 microns from an imaging lens, through which they hoped to see individual fermions.

    However, seeing fermions requires shining light on them, causing a photon to essentially knock a fermionic atom out of its well, and potentially out of the system entirely.

    “We needed a clever technique to keep the atoms cool while looking at them,” Zwierlein says.

    His team decided to use a two-laser approach to further cool the atoms; the technique manipulates an atom’s particular energy level, or vibrational energy. Each atom occupies a certain energy state — the higher that state, the more active the particle is. The team shone two laser beams of differing frequencies at the lattice. The difference in frequencies corresponded to the energy between a fermion’s energy levels. As a result, when both beams were directed at a fermion, the particle would absorb the smaller frequency, and emit a photon from the larger-frequency beam, in turn dropping one energy level to a cooler, more inert state. The lens above the lattice collects the emitted photon, recording its precise position, and that of the fermion.

    Zwierlein says such high-resolution imaging of more than 1,000 fermionic atoms simultaneously would enhance our understanding of the behavior of other fermions in nature — particularly the behavior of electrons. This knowledge may one day advance our understanding of high-temperature superconductors, which enable lossless energy transport, as well as quantum systems such as solid-state systems or nuclear matter.

    “The Fermi gas microscope, together with the ability to position atoms at will, might be an important step toward the realization of a quantum computer based on fermions,” Zwierlein says. “One would thus harness the power of the very same intricate quantum rules that so far hamper our understanding of electronic systems.”

    Zwierlein says it is a good time for Fermi gas microscopists: Around the same time his group first reported its results, teams from Harvard and the University of Strathclyde in Glasgow also reported imaging individual fermionic atoms in optical lattices, indicating a promising future for such microscopes.

    Zoran Hadzibabic, a professor of physics at Trinity College, says the group’s microscope is able to detect individual atoms “with almost perfect fidelity.”

    “They detect them reliably, and do so without affecting their positions — that’s all you want,” says Hadzibabic, who did not contribute to the research. “So far they demonstrated the technique, but we know from the experience with bosons that that’s the hardest step, and I expect the scientific results to start pouring out.”

    This research was funded in part by the National Science Foundation, the Air Force Office of Scientific Research, the Office of Naval Research, the Army Research Office, and the David and Lucile Packard Foundation.

    See the full article here.

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  • richardmitnick 10:40 am on May 8, 2015 Permalink | Reply
    Tags: , , , , Microscopy   

    From AAAS: “Electron microscopes close to imaging individual atoms” 

    AAAS

    AAAS

    7 May 2015
    Robert F. Service

    1
    This composite image of the protein β-galactosidase shows the progression of cryo-EM’s ability to resolve a protein’s features from mere blobs (left) a few years ago to the ultrafine 0.22-nanometer resolution today (right). Veronica Falconieri/ Subramaniam Lab/CCR/ NCI/ NIH

    Today’s digital photos are far more vivid than just a few years ago, thanks to a steady stream of advances in optics, detectors, and software. Similar advances have also improved the ability of machines called cryo-electron microscopes (cryo-EMs) to see the Lilliputian world of atoms and molecules. Now, researchers report that they’ve created the highest ever resolution cryo-EM image, revealing a druglike molecule bound to its protein target at near atomic resolution. The resolution is so sharp that it rivals images produced by x-ray crystallography, long the gold standard for mapping the atomic contours of proteins. This newfound success is likely to dramatically help drugmakers design novel medicines for a wide variety of conditions.

    “This represents a new era in imaging of proteins in humans with immense implications for drug design,” says Francis Collins, who heads the U.S. National Institutes of Health in Bethesda, Maryland. Collins may be partial. He’s the boss of the team of researchers from the National Cancer Institute (NCI) and the National Heart, Lung, and Blood Institute that carried out the work. Still, others agree that the new work represents an important milestone. “It’s a major advance in the technology,” says Wah Chiu, a cryo-EM structural biologist at Baylor College of Medicine in Houston, Texas. “It shows [cryo-EM] technology is here.”

    Cryo-EM has long seemed behind the times—an old hand tool compared with the modern power tools of structural biology. The two main power tools, x-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy, enable researchers to pin down the position of protein features to less than 0.2 nanometers, good enough to see individual atoms. By contrast, cryo-EM has long been limited to a resolution of 0.5 nm or more.

    Cryo-EM works by firing a beam of electrons at a thin film containing myriad copies of a protein that have been instantly frozen in place by plunging them in liquid nitrogen. Detectors track the manner in which electrons scatter off different atoms in the protein. When an image is taken, the proteins are strewn about in random orientations. So researchers use imaging software to do two things; first, they align their images of individual proteins into a common orientation. Then, they use the electron scattering data to reconstruct the most likely position of all the protein’s amino acids and—if possible—its atoms.

    Cryo-EM has been around for decades. But until recently its resolution hasn’t even been close to crystallography and NMR. “We used to be called the field of blob-ology,” says Sriram Subramaniam, a cryo-EM structural biologist at NCI, who led the current project. But steady improvements to the electron beam generators, detectors, and imaging analysis software have slowly helped cryo-EM inch closer to the powerhouse techniques. Earlier this year, for example, two groups of researchers broke the 0.3-nm-resolution benchmark, enough to get a decent view of the side arms of two proteins’ individual amino acids. Still, plenty of detail in the images remained fuzzy.

    For their current study, Subramaniam and his colleagues sought to refine their images of β-galactosidase, a protein they imaged last year at a resolution of 0.33 nm. The protein serves as a good test case, Subramaniam says, because researchers can compare their images to existing x-ray structures to check their accuracy. Subramaniam adds that the current advance was more a product of painstaking refinements to a variety of techniques—including protein purification procedures that ensure each protein copy is identical and software improvements that allow researchers to better align their images. Subramaniam and his colleagues used some 40,000 separate images to piece together the final shape of their molecule. They report online today in Science that these refinements allowed them to produce a cryo-EM image of β-galactosidase at a resolution of 0.22 nm, not quite sharp enough to see individual atoms, but clear enough to see water molecules that bind to the protein in spots critical to the function of the molecule.

    That level of detail is equal to the resolution of many structures using x-ray crystallography, Chiu says. That’s vital, he adds, because for x-ray crystallography to work, researchers must produce millions of identical copies of a protein and then coax them to align in exactly the same orientation as they solidify into a crystal. But many proteins resist falling in line, making it impossible to determine their x-ray structure. NMR spectroscopy doesn’t require crystals, but it works only on small proteins. Cryo-EM represents the best of both worlds: It can work with massive proteins, but it doesn’t require crystals.

    As a result, the new advances could help structural biologists map vast numbers of new proteins they’ve never mapped before, Chiu says. That, in turn, could help drug developers design novel drugs for a multitude of conditions associated with different proteins. But one thing the technique has already shown is crystal clear, that in imaging, as well as biology, slow, evolutionary advances over time can produce big results.

    See the full article here.

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 5:11 am on January 20, 2015 Permalink | Reply
    Tags: , Microscopy,   

    From Yale: “New laser could upgrade the images in tomorrow’s technology” 

    Yale University bloc

    Yale University

    January 19, 2015
    Jim Shelton
    james.shelton@yale.edu
    203-361-8332

    1
    Shutterstock

    A new semiconductor laser developed at Yale has the potential to significantly improve the imaging quality of the next generation of high-tech microscopes, laser projectors, photo lithography, holography, and biomedical imaging.

    Based on a chaotic cavity laser, the technology combines the brightness of traditional lasers with the lower image corruption of light emitting diodes (LEDs). The search for better light sources for high-speed, full-field imaging applications has been the focus of intense experimentation and research in recent years.

    The new laser is described in a paper in the Jan. 19 online edition of the Proceedings of the National Academy of Sciences. Several Yale labs and departments collaborated on the research, with contributions from scientists in applied physics, electrical and biomedical engineering, and diagnostic radiology.

    “This chaotic cavity laser is a great example of basic research ultimately leading to a potentially important invention for the social good,” said co-author A. Douglas Stone, the Carl A. Morse Professor and chair of applied physics, and professor of physics. “All of the foundational work was primarily motivated by a desire to understand certain classes of lasers — random and chaotic — with no known applications. Eventually, with input from other disciplines, we discovered that these lasers are uniquely suited for a wide class of problems in imaging and microscopy.”

    One of those problems is known as “speckle.” Speckle is a random, grainy pattern, caused by high spatial coherence that can corrupt the formation of images when traditional lasers are used. A way to avoid such distortion is by using LED light sources. The problem is, LEDs are not bright enough for high-speed imaging.

    The new, electrically pumped semiconductor laser offers a different approach. It produces an intense emission, but with low spatial coherence.

    “For full-field imaging, the speckle contrast should be less than ~4% to avoid any disturbance for human inspection,” explained Hui Cao, professor of applied physics and of physics, who is the paper’s corresponding author. “As we showed in the paper, the standard edge-emitting laser produced speckle contrast of ~50%, while our laser has the speckle contrast of 3%. So our new laser has completely eliminated the issue of coherent artifact for full-field imaging.”

    Co-author Michael A. Choma, assistant professor of diagnostic radiology, pediatrics, and biomedical engineering, said laser speckle is a major barrier in the development of certain classes of clinical diagnostics that use light. “It is tremendously rewarding to work with a team of colleagues to develop speckle-free lasers,” Choma said. “It also is exciting to think about the new kinds of clinical diagnostics we can develop.”

    The first author of the paper is Brandon Redding. Additional authors included Alexander Cerjan, Xue Huang, and Minjoo Larry Lee.

    Redding and Cao designed, fabricated, and tested the new laser. Lee and Huang grew the laser’s semiconductor wafer via molecular beam epitaxy, and helped in fabrication and testing. Choma aided in the design and performance criteria for the laser, provided expertise in spatial coherence and speckle in imaging, and is working with Redding to apply the laser for full-field imaging at Yale School of Medicine. Stone and Cerjan modeled the laser and analyzed its characteristics.

    See the full article here.

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    Yale University Campus

    Yale University comprises three major academic components: Yale College (the undergraduate program), the Graduate School of Arts and Sciences, and the professional schools. In addition, Yale encompasses a wide array of centers and programs, libraries, museums, and administrative support offices. Approximately 11,250 students attend Yale.

     
  • richardmitnick 5:51 am on August 2, 2014 Permalink | Reply
    Tags: , , Microscopy   

    From UC Berkeley: “CNR Purchases Powerful New Microscope” 

    UC Berkeley

    UC Berkeley

    August 1, 2014
    Karyn Houston

    A microscopy expert at UC Berkeley has won a grant to purchase an amazingly powerful new microscope that will enable scientists to study the tiniest of organisms.

    “This new microscope will enable researchers to see objects that are impossible to see using technology available at Berkeley today,” said Steve Ruzin, director of the Biological Imaging Facility, located on the UC Berkeley campus in Koshland Hall, in the College of Natural Resources.

    Ruzin is an expert in microscopes and his cutting-edge Biological Imaging Facilty serves thousands of faculty, students and staff. Not only are a wide variety of microscopes available for researchers to use, but the lab also teaches students and other researchers about microscopy, the technical field of using microscopes to view samples and objects that cannot be seen with the naked eye.

    “Cells have bustling shipping centers,” said Amita Gorur, a graduate student in the Randy Schekman Lab at UC Berkeley. “The Elyra PS.1 Super Resolution microscope will allow me to track and visualize cargo on a freight car moving along cellular rail roads from destination A to B in real time. These cellular shipping units are so small that only the resolution achieved by this microscope will allow us to see them. That’s powerful!”

    flagella
    Flagella of Giardia

    micro

    Differentiating Objects from One Another

    giardia
    Giardia

    The new $600,000 instrument, purchased with a National Institutes of Health grant, is a “Structured Illumination Microscope” that allows researchers to image and differentiate different parts of a cell, using different fluorescent dyes.

    “In microscopy, and any optical system, to ‘see’ something is the ability of the system (microscope, telescope, eye) to determine whether two closely spaced objects are, in fact, two objects or really only one larger object,” Ruzin said. This “limit of resolution” is determined by the wavelength of light that is used to illuminate the sample. The resolution limit was defined in the 1880s by the German scientist Ernst Abbe, and it is still valid today.

    “In practical terms this means that the smallest object that can be resolved in a light microscope is about one third of a micrometer, or 300 nanometers,” Ruzin said. To put that size into perspective:

    New Technology

    In the last few years three separate technologies have become available that overcome the limit of resolution. The new microscope uses one of these technologies called “Structured Illumination,” that illuminates the sample with a known pattern of light.

    The illumination pattern induces a complex light pattern that is emitted from the sample. Subsequent computer processing of the emitted pattern reveals sub-resolution structures within the sample. The new microscope will achieve a resolution of 100nm, and will be able to see objects that are 10 times smaller than a bacterium, or 10,000 times smaller than a period.

    Steve RuzinThis ability to resolve objects smaller than the theoretical limit is the reason a microscope like this is called a “Super-Resolution Microscope”. It will enable researchers to see:

    Arash Komeili’s lab in the Department of Plant & Microbial Biology is one of the many labs on campus that will benefit from the new instrument.

    The Komeili group studies magnetosomes, bacterial organelles 50-70 nm in diameter that control the formation of magnetic nanoparticles. Due to their small size and tight arrangement within the cell, conventional fluorescence microscopy cannot distinguish between individual magnetosomes.

    “We anticipate that the improved resolution of the Structured Illumination Microscope will allow us to study the dynamics of specific proteins at the individual magnetosome level,” Komeili said.

    See the full article here.

    Founded in the wake of the gold rush by leaders of the newly established 31st state, the University of California’s flagship campus at Berkeley has become one of the preeminent universities in the world. Its early guiding lights, charged with providing education (both “practical” and “classical”) for the state’s people, gradually established a distinguished faculty (with 22 Nobel laureates to date), a stellar research library, and more than 350 academic programs.

    UC Berkeley Seal


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  • richardmitnick 6:33 pm on June 30, 2014 Permalink | Reply
    Tags: , , Microscopy   

    From Argonne Lab: “Microscopy charges ahead” 

    News from Argonne National Laboratory

    May 28, 2014
    Jared Sagoff

    Ferroelectric materials – substances in which there is a slight and reversible shift of positive and negative charges – have surfaces that are coated with electrical charges like roads covered in snow. Accumulations can obscure lane markings, making everyone unsure which direction traffic ought to flow; in the case of ferroelectrics, these accumulations are other charges that “screen” the true polarization of different regions of the material.

    Ferroelectric materials are of special interest to researchers as a potential new form of computer memory and for sensor technologies.

    two
    Argonne materials scientists Seungbum Hong (left) and Andreas Roelofs adjust an atomic force microscope.Photo credit: Wes Agresta/Argonne National Laboratory.

    In order to see this true polarization quickly and efficiently, researchers at the U.S. Department of Energy’s Argonne National Laboratory have developed a new technique called charge gradient microscopy. Charge gradient microscopy uses the tip of a conventional atomic force microscope to scrape and collect the surface screen charges.

    “The whole process works much like a snowplow scraping along the roads,” said Argonne materials scientist Seungbum Hong, who led the research. “Before, all we had was a snowshovel.”

    Ferroelectric materials are not usually polarized in any particular way, but they are rather the combination of different domains that are each polarized in different directions. “The end goal of the research is to be able to map these different regions quickly and accurately,” Hong said.

    “Until now, the process of trying to map these regions has been incredibly arduous and time-consuming,” added Argonne Nanoscience and Technology interim division director Andreas Roelofs, who came up with the idea for the study. “What was taking us 10 to 15 minutes now takes seconds.”

    Previous efforts in this arena had focused on the application of a different kind of microscope using piezoresponse force microscopy (PFM). In this technique, an applied voltage causes a small displacement of atoms in the material, generating a noticeable mechanical effect, or vibration. In reverse, the same phenomenon is responsible for the workings of the lighters in gas grills.

    The problem with PFM is that it is very slow and requires sophisticated equipment to measure a tiny motion of the material. “Before, we had to sit on one spot for a long time to get enough signal to understand how the material moves because we could just barely sense it,” Roelofs said. “For the past 15 years or so, we’ve tried to increase the speed of the measurements and made only modest progress while adding a lot of complexity.”

    “Now, everyone can use a standard tool to do this work much more cheaply and efficiently,” he added.

    An article based on the study appears in the April 23 early edition of the Proceedings of the National Academy of Sciences.

    This research was funded by the U.S. Department of Energy’s Office of Science.

    See the full article here.

    Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.

    The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security. To learn more about the Office of Science X-ray user facilities, visit http://science.energy.gov/user-facilities/basic-energy-sciences/.

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    Argonne Lab Campus


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  • richardmitnick 9:00 pm on May 28, 2014 Permalink | Reply
    Tags: , , Microscopy   

    From Argonne Lab: “Microscopy charges ahead: 

    News from Argonne National Laboratory

    May 28, 2014
    Jared Sagoff

    Ferroelectric materials – substances in which there is a slight and reversible shift of positive and negative charges – have surfaces that are coated with electrical charges like roads covered in snow. Accumulations can obscure lane markings, making everyone unsure which direction traffic ought to flow; in the case of ferroelectrics, these accumulations are other charges that “screen” the true polarization of different regions of the material.

    Ferroelectric materials are of special interest to researchers as a potential new form of computer memory and for sensor technologies.

    In order to see this true polarization quickly and efficiently, researchers at the U.S. Department of Energy’s Argonne National Laboratory have developed a new technique called charge gradient microscopy. Charge gradient microscopy uses the tip of a conventional atomic force microscope to scrape and collect the surface screen charges.

    two
    Argonne materials scientists Seungbum Hong (left) and Andreas Roelofs adjust an atomic force microscope. Click to enlarge. Photo credit: Wes Agresta/Argonne National Laboratory.

    “The whole process works much like a snowplow scraping along the roads,” said Argonne materials scientist Seungbum Hong, who led the research. “Before, all we had was a snowshovel.”

    Ferroelectric materials are not usually polarized in any particular way, but they are rather the combination of different domains that are each polarized in different directions. “The end goal of the research is to be able to map these different regions quickly and accurately,” Hong said.

    “Until now, the process of trying to map these regions has been incredibly arduous and time-consuming,” added Argonne Nanoscience and Technology interim division director Andreas Roelofs, who came up with the idea for the study. “What was taking us 10 to 15 minutes now takes seconds.”

    Previous efforts in this arena had focused on the application of a different kind of microscope using piezoresponse force microscopy (PFM). In this technique, an applied voltage causes a small displacement of atoms in the material, generating a noticeable mechanical effect, or vibration. In reverse, the same phenomenon is responsible for the workings of the lighters in gas grills.

    The problem with PFM is that it is very slow and requires sophisticated equipment to measure a tiny motion of the material. “Before, we had to sit on one spot for a long time to get enough signal to understand how the material moves because we could just barely sense it,” Roelofs said. “For the past 15 years or so, we’ve tried to increase the speed of the measurements and made only modest progress while adding a lot of complexity.”

    “Now, everyone can use a standard tool to do this work much more cheaply and efficiently,” he added.

    An article based on the study appears in the April 23 early edition of the Proceedings of the National Academy of Sciences.

    This research was funded by the U.S. Department of Energy’s Office of Science.

    See the full article here.

    Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science. For more visit http://www.anl.gov.

    The Advanced Photon Source at Argonne National Laboratory is one of five national synchrotron radiation light sources supported by the U.S. Department of Energy’s Office of Science to carry out applied and basic research to understand, predict, and ultimately control matter and energy at the electronic, atomic, and molecular levels, provide the foundations for new energy technologies, and support DOE missions in energy, environment, and national security. To learn more about the Office of Science X-ray user facilities, visit http://science.energy.gov/user-facilities/basic-energy-sciences/.

    Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science

    Argonne Lab Campus


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  • richardmitnick 7:52 am on October 4, 2013 Permalink | Reply
    Tags: , Microscopy, ,   

    From M.I.T.: “New kind of microscope uses neutrons” 

    October 4, 2013
    David L. Chandler, MIT News Office

    Researchers at MIT, working with partners at NASA, have developed a new concept for a microscope that would use neutrons — subatomic particles with no electrical charge — instead of beams of light or electrons to create high-resolution images.

    micro
    No image credit

    Among other features, neutron-based instruments have the ability to probe inside metal objects — such as fuel cells, batteries, and engines, even when in use — to learn details of their internal structure. Neutron instruments are also uniquely sensitive to magnetic properties and to lighter elements that are important in biological materials.

    The new concept has been outlined in a series of research papers this year, including one published this week in Nature Communications by MIT postdoc Dazhi Liu, research scientist Boris Khaykovich, professor David Moncton, and four others.

    See the full article here.


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  • richardmitnick 2:37 pm on July 29, 2013 Permalink | Reply
    Tags: , , Microscopy   

    From Caltech: “Pushing Microscopy Beyond Standard Limits” 

    Caltech Logo
    Caltech

    07/29/2013
    Kimm Fesenmaier

    “Engineers at the California Institute of Technology (Caltech) have devised a method to convert a relatively inexpensive conventional microscope into a billion-pixel imaging system that significantly outperforms the best available standard microscope. Such a system could greatly improve the efficiency of digital pathology, in which specialists need to review large numbers of tissue samples. By making it possible to produce robust microscopes at low cost, the approach also has the potential to bring high-performance microscopy capabilities to medical clinics in developing countries.

    ‘In my view, what we’ve come up with is very exciting because it changes the way we tackle high-performance microscopy,’ says Changhuei Yang, professor of electrical engineering, bioengineering and medical engineering at Caltech.

    scope
    Artist’s rendering of the new microscopy setup showing one element of an LED array illuminating a sample.

    Yang is senior author on a paper that describes the new imaging strategy, which appears in the July 28 early online version of the journal Nature Photonics.

    Until now, the physical limitations of microscope objectives—their optical lenses— have posed a challenge in terms of improving conventional microscopes. Microscope makers tackle these limitations by using ever more complicated stacks of lens elements in microscope objectives to mitigate optical aberrations. Even with these efforts, these physical limitations have forced researchers to decide between high resolution and a small field of view on the one hand, or low resolution and a large field of view on the other. That has meant that scientists have either been able to see a lot of detail very clearly but only in a small area, or they have gotten a coarser view of a much larger area.

    ‘We found a way to actually have the best of both worlds,’ says Guoan Zheng, lead author on the new paper and the initiator of this new microscopy approach from Yang’s lab. ‘We used a computational approach to bypass the limitations of the optics. The optical performance of the objective lens is rendered almost irrelevant, as we can improve the resolution and correct for aberrations computationally.'”

    See the full article here.

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”
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