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  • richardmitnick 6:44 pm on September 22, 2014 Permalink | Reply
    Tags: , , , , X-ray Technology   

    From Stanford: “Stanford researchers create ‘evolved’ protein that may stop cancer from spreading” 

    Stanford University Name
    Stanford University

    September 21, 2014
    Tom Abate

    Experimental therapy stopped the metastasis of breast and ovarian cancers in lab mice, pointing toward a safe and effective alternative to chemotherapy.

    A team of Stanford researchers has developed a protein therapy that disrupts the process that causes cancer cells to break away from original tumor sites, travel through the bloodstream and start aggressive new growths elsewhere in the body.

    This process, known as metastasis, can cause cancer to spread with deadly effect.

    “The majority of patients who succumb to cancer fall prey to metastatic forms of the disease,” said Jennifer Cochran, an associate professor of bioengineering who describes a new therapeutic approach in Nature Chemical Biology.

    Today doctors try to slow or stop metastasis with chemotherapy, but these treatments are unfortunately not very effective and have severe side effects.

    The Stanford team seeks to stop metastasis, without side effects, by preventing two proteins – Axl and Gas6 – from interacting to initiate the spread of cancer.

    Axl proteins stand like bristles on the surface of cancer cells, poised to receive biochemical signals from Gas6 proteins.

    When two Gas6 proteins link with two Axls, the signals that are generated enable cancer cells to leave the original tumor site, migrate to other parts of the body and form new cancer nodules.

    To stop this process Cochran used protein engineering to create a harmless version of Axl that acts like a decoy. This decoy Axl latches on to Gas6 proteins in the bloodstream and prevents them from linking with and activating the Axls present on cancer cells.

    In collaboration with Professor Amato Giaccia, co-director of the Radiation Biology Program in the Stanford Cancer Center, the researchers gave intravenous treatments of this bioengineered decoy protein to mice with aggressive breast and ovarian cancers.

    two
    Jennifer Cochran and Amato Giaccia are members of a team of researchers who have developed an experimental therapy to treat metastatic cancer.

    Mice in the breast cancer treatment group had 78 percent fewer metastatic nodules than untreated mice. Mice with ovarian cancer had a 90 percent reduction in metastatic nodules when treated with the engineered decoy protein.

    “This is a very promising therapy that appears to be effective and nontoxic in preclinical experiments,” Giaccia said. “It could open up a new approach to cancer treatment.”

    Giaccia and Cochran are scientific advisors to Ruga Corp., a biotech startup in Palo Alto that has licensed this technology from Stanford. Further preclinical and animal tests must be done before determining whether this therapy is safe and effective in humans.

    Greg Lemke, of the Molecular Neurobiology Laboratory at the Salk Institute, called this “a prime example of what bioengineering can do” to open up new therapeutic approaches to treat metastatic cancer.

    “One of the remarkable things about this work is the binding affinity of the decoy protein,” said Lemke, a noted authority on Axl and Gas6 who was not part of the Stanford experiments.

    “The decoy attaches to Gas6 up to a hundredfold more effectively than the natural Axl,” Lemke said. “It really sops up Gas6 and takes it out of action.”
    Directed evolution

    The Stanford approach is grounded on the fact that all biological processes are driven by the interaction of proteins, the molecules that fit together in lock-and-key fashion to perform all the tasks required for living things to function.

    In nature proteins evolve over millions of years. But bioengineers have developed ways to accelerate the process of improving these tiny parts using technology called directed evolution. This particular application was the subject of the doctoral thesis of Mihalis Kariolis, a bioengineering graduate student in Cochran’s lab.

    Using genetic manipulation, the Stanford team created millions of slightly different DNA sequences. Each DNA sequence coded for a different variant of Axl.

    The researchers then used high-throughput screening to evaluate over 10 million Axl variants. Their goal was to find the variant that bound most tightly to Gas6.

    Kariolis made other tweaks to enable the bioengineered decoy to remain in the bloodstream longer and also to tighten its grip on Gas6, rendering the decoy interaction virtually irreversible.

    Yu Rebecca Miao, a postdoctoral scholar in Giaccia’s lab, designed the testing in animals and worked with Kariolis to administer the decoy Axl to the lab mice. They also did comparison tests to show that sopping up Gas6 resulted in far fewer secondary cancer nodules.

    Irimpan Mathews, a protein crystallography expert at SLAC National Accelerator Laboratory, joined the research effort to help the team better understand the binding mechanism between the Axl decoy and Gas6.

    Protein crystallography captures the interaction of two proteins in a solid form, allowing researchers to take X-ray-like images of how the atoms in each protein bind together. These images showed molecular changes that allowed the bioengineered Axl decoy to bind Gas6 far more tightly than the natural Axl protein.
    Next steps

    Years of work lie ahead to determine whether this protein therapy can be approved to treat cancer in humans. Bioprocess engineers must first scale up production of the Axl decoy to generate pure material for clinical tests. Clinical researchers must then perform additional animal tests in order to win approval for and to conduct human trials. These are expensive and time-consuming steps.

    But these early, hopeful results suggest that the Stanford approach could become a nontoxic way to fight metastatic cancer.

    Glenn Dranoff, a professor of medicine at Harvard Medical School and a leading researcher at the Dana-Farber Cancer Institute, reviewed an advance copy of the Stanford paper but was otherwise unconnected with the research. “It is a beautiful piece of biochemistry and has some nuances that make it particularly exciting,” Dranoff said, noting that tumors often have more than one way to ensure their survival and propagation.

    Axl has two protein cousins, Mer and Tyro3, that can also promote metastasis. Mer and Tyro3 are also activated by Gas6.

    “So one therapeutic decoy might potentially affect all three related proteins that are critical in cancer development and progression,” Dranoff said.

    Erinn Rankin, a postdoctoral fellow in the Giaccia lab, carried out proof of principle experiments that paved the way for this study.

    Other co-authors on the Nature Chemical Biology paper include Douglas Jones, a former doctoral student, and Shiven Kapur, a postdoctoral scholar, both of Cochran’s lab, who contributed to the protein engineering and structural characterization, respectively.

    Cochran said Stanford’s support for interdisciplinary research made this work possible.

    Stanford ChEM-H (Chemistry, Engineering & Medicine for Human Health) provided seed funds that allowed Cochran and Mathews to collaborate on protein structural studies.

    The Stanford Wallace H. Coulter Translational Research Grant Program, which supports collaborations between engineers and medical researchers, supported the efforts of Cochran and Giaccia to apply cutting-edge bioengineering techniques to this critical medical need.

    See the full article here.

    Leland and Jane Stanford founded the University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members

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  • richardmitnick 3:27 pm on September 15, 2014 Permalink | Reply
    Tags: , , , PETRA III, , X-ray Technology   

    From DESY: “Double topping-out celebrations at DESY” 

    DESY
    DESY

    Two new experimental halls for research light source PETRA III

    Today DESY celebrates the topping-out of two large experimental halls for the research light source PETRA III.Ten additional beamlines, which will serve in the PETRA III particle accelerator’s high intensity X-ray experiments, are under construction in a space measuring approximately 6000 square meters; the facility will also include en-suite offices and laboratory spaces for scientists.The experimentation capabilities at the PETRA III synchrotron radiation source will be considerably increased due to the expansion project.The first new beamlines of the 80-million-Euro-project will be ready for operation beginning in autumn 2015.
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    pit

    “With the new experimental stations, we are significantly expanding the research capabilities of PETRA III, for example, with new nanospectroscopy and materials research technologies,” says Chairman of the DESY Board of Directors Professor Helmut Dosch at the event. “At the same time, we will be fulfilling the enormous worldwide scientific demand for the best synchrotron radiation source in the world.”

    Hamburg´s Science Senator Dr. Dorothee Stapelfeldt says: “The senate’s aim is to develop Hamburg into one of the leading locations for research and innovation in Europe.In order to do so, it is essential to further raise the profiles of universities and research institutions in close dialogue with all stakeholders.Hamburg already occupies a leading position in structural research.The ground-breaking cooperation between DESY, the university and their partners at the Bahrenfeld research campus has been clearly recognized internationally.With the two new experimental halls, PETRA’s synchrotron radiation will be made available to even more researchers from all over the world in the future.”

    “With a total of ten new beamlines, the allure of Hamburg as a location for cutting-edge research will continue to increase, nationally and internationally,” says Dr. Beatrix Vierkorn-Rudolph (BMBF), Chairperson of the DESY Foundation Council. “With its excellent research opportunities, PETRA III contributes to rapidly transfering the results of basic research into application while also strengthening the innovative power of Germany.”

    DESY’s 2.3-kilometre-long PETRA III ring accelerator produces high intensity, highly collimated X-ray pulses for a diverse range of physical, biological and chemical experiments.Fourteen measuring stations, which can accommodate up to thirty experiments, already exist in an approximately 300-metre-long experimental hall.The properties of light pulses, which PETRA delivers to the different measuring stations, are thereby precisely attuned to the different research disciplines.Using the extremely brilliant X-rays, researchers study, for example, innovative solar cells, observe the dynamics of cell membranes and analyse fossilised dinosaur eggs.

    PETRA III, the world´s best X-ray source of its kind, has been heavily over-booked since it began operations in 2009.The PETRA III Extension Project was begun in December 2013 to give more scientists access to the unique experimental possibilities of this research light source and to broaden PETRA III’s research portfolio in experimental technologies:measuring approximately 6000 square meters in their entirety, the two new experimental halls house enough space for technical installations of up to ten additional beam lines, and an additional 1400 square metres provide office and laboratory space for the scientists.The beam lines and measuring instruments in the new halls are under construction in close cooperation with the future user community and are, in part, collaborative research projects.Three of the future PETRA beamlines will be constructed as an international partnership with Sweden, India and Russia.

    Altogether approximately 170 metres of the PETRA tunnel and accelerator have been dismantled since February to build the new experimental halls. Since August, the accelerator, equipped with special magnets for producing X-ray radiation, has been under reconstruction within the new tunnel areas that have already been completed.After the preliminary construction phase of the experimental halls, they are to be developed further from December 2014 onward; the accelerator will at the same time resume operation.The experiments will re-start in the PETRA III experimental hall “Max von Laue” beginning in April 2015 and the first measuring stations in the new, still unnamed halls should gradually become ready for operation in autumn 2015 and the start of 2016.

    The extension’s total budget of approximately 80 million Euros stems in large part from the Helmholtz Association’s expansion funds as well as funds from the Federal Ministry of Research, the Free and Hanseatic City of Hamburg and DESY.Collaborative partners from Germany and abroad cover approximately one third of the costs.

    See the full article here.

    desi

    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

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  • richardmitnick 3:43 pm on September 12, 2014 Permalink | Reply
    Tags: , , , , X-ray Technology   

    From DESY: “Researchers X-Ray Living Cancer Cells” 

    DESY
    DESY

    27.02.2014

    Nanodiffraction opens up new insights into the physics of life

    Göttingen-based scientists working at DESY’s PETRA III research light source have carried out the first studies of living biological cells using high-energy X-rays. The new method shows clear differences in the internal cellular structure between living and dead, chemically fixed cells that are often analysed. “The new method for the first time enables us to investigate the internal structures of living cells in their natural environment using hard X-rays,” emphasises the leader of the working group, Prof. Sarah Köster from the Institute for X-Ray Physics of the University of Göttingen. The researchers present their work in the scientific journal Physical Review Letters.
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    c ells
    X-ray scan of chemically fixed cells. Each pixel represents a full diffraction image. The colours indicate how strong the X-rays are scattered at each individual point. Credit: Britta Weinhausen/University of Göttingen

    Thanks to analytical methods with ever-higher resolution, scientists today can study biological cells at the level of individual molecules. The cells are frequently chemically fixed before they are studied with the help of optical, X-ray or electron microscopes. The process of chemical fixation involves immersing the cells in a type of chemical preservative which fixes all of the cell’s organelles and even the proteins in place. “Minor changes to the internal structure of the cells are unavoidable in this process,” emphasises Köster. “In our studies, we were able to show these changes in direct comparison for the first time.”

    The team used cancer cells from the adrenal cortex for their analyses. They grew the cells on a silicon nitrite substrate, which is almost transparent to X-rays. In order to keep the cells alive in the experimental chamber during the experiment, they were supplied with nutrients, and their metabolic products were pumped away via fine channels just 0.5 millimetres in diameter. “The biological cells are thus located in a sample environment which very closely resembles their natural environment,” explains Dr. Britta Weinhausen from Köster’s group, the paper’s first author.

    The experiments were carried out at the Nanofocus Setup (GINIX) of PETRA III’s experimental station P10. The scientists used the brilliant X-ray beam from PETRA III to scan the cells in order to obtain information about their internal nanostructure. “Each frame was exposed for just 0.05 seconds, in order to avoid damaging the living cells too quickly”, explains co-author Dr. Michael Sprung from DESY. “Even nanometre-scale structures can be measured with the GINIX assembly, thanks to the combination of PETRA III’s high brilliance and the GINIX setup which is matched to the source.”

    The researchers studied living and chemically fixed cells using this so-called nanodiffraction technique and compared the cells’ internal structures on the basis of the X-ray diffraction images. The results showed that the chemical fixation produces noticeable differences in the cellular structure on a scale of 30 to 50 nanometres (millionths of a millimetre).

    “Thanks to the ever-greater resolution of the various investigative techniques, it is increasingly important to know whether the internal structure of the sample changes during sample preparation,” explains Köster. In future, the new technique will make it possible to study unchanged living cells at high resolution. Although other methods have an even higher resolution than X-ray scattering, they require a chemical fixation or complex and invasive preparation of the cells. Lower-energy, so-called soft X-rays have already been used for studies of living cells. However, the study of structures with sizes as small as 12 nanometres first becomes possible through the analysis of diffraction images produced using hard X-rays.

    See the full article here.

    desi

    DESY is one of the world’s leading accelerator centres. Researchers use the large-scale facilities at DESY to explore the microcosm in all its variety – from the interactions of tiny elementary particles and the behaviour of new types of nanomaterials to biomolecular processes that are essential to life. The accelerators and detectors that DESY develops and builds are unique research tools. The facilities generate the world’s most intense X-ray light, accelerate particles to record energies and open completely new windows onto the universe. 
That makes DESY not only a magnet for more than 3000 guest researchers from over 40 countries every year, but also a coveted partner for national and international cooperations. Committed young researchers find an exciting interdisciplinary setting at DESY. The research centre offers specialized training for a large number of professions. DESY cooperates with industry and business to promote new technologies that will benefit society and encourage innovations. This also benefits the metropolitan regions of the two DESY locations, Hamburg and Zeuthen near Berlin.

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  • richardmitnick 2:33 pm on September 12, 2014 Permalink | Reply
    Tags: , , , , X-ray Technology   

    From physicsworld: “Synchrotron X-rays track fluids in the lungs” 

    physicsworld
    physicsworld.com

    Sep 12, 2014
    Ian Randall

    A new method of soft-tissue imaging could allow doctors to monitor respiratory treatments of cystic-fibrosis patients, reports an international research team. The technique – which measures the refraction of a grid pattern of X-rays passing through the lungs – has been successfully demonstrated in live mice, and could eventually find application in visualizing other soft tissues, such as the brain and heart.

    synchro
    Synchrotron source: phase-contrast imaging in the lab

    Cystic fibrosis is a life-threatening genetic disorder that affects the exocrine glands, resulting in unusually thick secretions of mucus. In lungs, mucus is supposed to keep the airways moist, along with forming a conveyor belt, moved by beating cilia, which carries away foreign particles and pathogens. In cystic-fibrosis patients, however, the thicker mucus flows less easily – resulting in a build-up that can cause inflammation, breathing difficulties and increased susceptibility to bacterial infection.

    Respiratory therapies for cystic-fibrosis patients typically focus on increasing hydration of the airways to improve mucus flow. Tracking the progress of these treatments, however, is challenging. “At the moment, we typically need to wait for a cystic-fibrosis treatment to have an effect on lung health, measured by either a lung CT scan or breath measurement, to see how effective it is,” explains lead researcher Kaye Morgan from Monash University in Australia. With successful medications often taking months to have a measurable impact, progress in developing new treatments is correspondingly slow.

    Fast yet sensitive

    The challenge lies in imaging the surface layers of liquid in the airways. These are usually only a few tens of microns across, bear a close resemblance to the underlying tissue and – given the passage of air in and out of lungs – constantly move around. Consequently, any technique for imaging this interface needs to be high-resolution, as well as sufficiently fast and sensitive.

    mouse
    Single-grid-based phase-contrast X-ray imaging reveals a liquid surface layer in the lungs of a live mouse
    Sharper image: X-rays reveal a liquid surface layer

    Morgan and colleagues have developed an imaging method that they call single-grid-based phase-contrast X-ray imaging. Unlike conventional radiography, which measures the absorption of X-rays, the new approach measures the refraction of a grid pattern of radiation as it passes through the soft tissues.

    “A good analogy is the patterns we see on the bottom of swimming pools,” explains Morgan. At the detector, the X-ray grid will appear distorted in accordance with the properties of the tissues that the rays have passed through – much in the same way that tiles in a pool appear distorted when seen through water. “By tracking the distortions in the grid pattern, we can reconstruct the airway structures.”

    Anaesthetized mice

    To test their method, the researchers imaged the airways of eight anaesthetized mice. Using a nebulizer, each mouse was treated first with a saline control solution, and then with a treatment designed to block the dehydrating effect of the cells lining the airway. X-rays from a synchrotron travelled through a 25.4 µm grid to create the desired pattern; this produced images at the detector with 0.18 µm-sized pixels. Images were recorded at three-minute intervals for 15 minutes after each treatment.

    By tracking the distortions in the grid pattern, we can reconstruct the airway structures
    Kaye Morgan, Monash University

    The method successfully imaged the airway, surface liquids and underlying tissues. A noticeable increase in the surface hydration depth was observed after treatment in comparison with the control. “The new imaging method allows us, for the first time, to non-invasively see how the treatment is working, ‘live’ on the airway surface,” Morgan says.

    “This is a novel and interesting biomedical application,” says Mark Anastasio, a biomedical engineer from Washington University in St Louis. With existing solutions unable to reveal such subtle soft-tissue interfaces, he adds, this result “motivates the further development of X-ray phase-contrast imaging technologies”.
    Practical issues

    Ke Li, a medical physicist from the University of Wisconsin-Madison, points out that making measurements on live mice “is a huge step along the course of applying phase-contrast X-ray projection imaging to medical imaging”. However, Li questions the practicality of using a synchrotron X-ray source in a clinical environment, especially given the high radiation dose necessary for such an ultra-fine pixel size.

    Some of these concerns could soon be addressed, with Morgan and colleagues now exploring how their work might translate into a clinical setting. At the same time, the team is investigating other possible medical applications, looking both at lungs and other soft tissues, such as the brain and heart.

    See the full article here.

    PhysicsWorld is a publication of the Institute of Physics. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application.

    We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.
    IOP Institute of Physics

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  • richardmitnick 8:14 am on September 12, 2014 Permalink | Reply
    Tags: , , , X-ray Technology   

    From SLAC: “SLAC Scientists Win Prizes for X-ray Laser Work” 


    SLAC Lab

    September 11, 2014

    Three scientists at the Department of Energy’s SLAC National Accelerator Laboratory received international prizes for their achievements in free-electron laser science, a field that has rapidly accelerated since the launch of SLAC’s X-ray laser five years ago.

    The annual prizes were awarded Aug. 27 during FEL 2014, the 36th International Free Electron Laser Conference, in Basel, Switzerland. The SLAC winners are:

    Zhirong Huang, a SLAC associate professor of photon science and PPA who has participated in pioneering projects related to the design and improvement of SLAC’s Linac Coherent Light Source (LCLS) X-ray laser, a Department of Energy Office of Science User Facility. He is a co-recipient of the 2014 FEL Prize, which recognizes significant contributions to the field.
    William Fawley, formerly of Lawrence Berkeley National Laboratory who now supports X-ray FEL R&D at SLAC, shares this year’s FEL Prize with Huang for his work in developing early FEL simulation codes, among other contributions. Fawley collaborates with the SLAC FEL theory group led by Huang, and has been working on a separate FEL project, FERMI@Elettra, in Trieste, Italy.
    Erik Hemsing, an associate staff scientist at SLAC, received the Young FEL Scientist Award for finding a new way to create beams of spiraling light, or “twisted light.”

    three
    From left, SLAC’s Erik Hemsing, Zhirong Huang and William Fawley accept awards during the 36th International Free Electron Laser Conference in Basel, Switzerland. At right is SLAC’s Paul Emma, who served as this year’s FEL Prize committee chairman. (Paul Scherrer Institute)

    “A lot of the people who have won the prize before me are my mentors and collaborators,” said Huang, who worked on X-ray FEL theory and an FEL test facility at Argonne National Laboratory before joining SLAC in 2002. “It’s a really great honor to join them.”

    Huang helped to build a “laser heater” that suppresses instability in SLAC’s linear accelerator in order for the electron bunches to emit intense X-ray light at LCLS, and he was part of the team that started up LCLS five years ago.

    More recently, he helped lead an effort to produce more intense X-ray pulses in a narrower band of wavelengths at LCLS, a process known as “self-seeding.” Huang also oversaw construction of a device that measures the duration of LCLS pulses.

    Fawley said of his award, “It is certainly a nice honor, but for me the real enjoyment is the recognition of all the work done with my collaborators” over the past several decades. He said he is probably best known in the FEL community for co-creating FEL simulation codes that supported high-power FEL research led by Lawrence Livermore National Laboratory in the 1980s and was later used to help investigate the properties of FEL designs like the LCLS. Recently, Fawley and Huang collaborated on a paper that characterizes the enhanced performance of a seeded FEL using the laser heater.

    Hemsing said, “I feel lucky to have the privilege to work alongside many of those who have made significant contributions to the FEL field over the last few decades.”

    Besides his study of twisted light, which has applications ranging from astronomy to fiber optics, Hemsing also has worked on a technique for tuning an electron beam with a laser to produce very short pulses of light with more predictable properties.

    Several new XFELs are under construction around the globe, including projects in Korea, Switzerland and Germany, adding to the XFELs already operating at SLAC and at labs in Germany and Japan.

    “I am surprised at the versatility of these machines, and at the speed at which good, new ideas are brought to reality,” Hemsing said. “It’s still a wide-open field.”

    See the full article here.

    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 7:17 pm on September 10, 2014 Permalink | Reply
    Tags: , , , X-ray Technology   

    From SLAC- “Plastics in Motion: Exploring the World of Polymers” 


    SLAC Lab

    September 10, 2014

    Experiment Shows Potential of X-ray Laser to Study Complex, Poorly Understood Materials

    Plastics are made of polymers, which are a challenge for scientists to study. Their chainlike strands of thousands of atoms are tangled up in a spaghetti-like jumble, their motion can be measured at many time scales and they are essentially invisible to some common X-ray study techniques.

    poly
    Illustration of a polystrene molecular chain and Styrofoam cups, which are made of polystyrene. (@iStockphoto/Devonyu, Martin McCarthy)

    gel
    This photograph shows a polymer in a molten, gel-like state. (@iStockphoto/Steve Bjorklund)

    A better understanding of polymers at the molecular scale, particularly as they are cooled from a molten state to a more solid form, could lead to improved manufacturing techniques and the creation of new, customizable materials.

    In an experiment at the Department of Energy’s SLAC National Accelerator Laboratory using SLAC’s Linac Coherent Light Source (LCLS) X-ray laser, a DOE Office of Science User Facility, scientists unraveled the complex behavior of polystyrene, a popular polymer found in packing foams and plastic cups, with a sequence of ultrabright X-ray laser pulses. Their work is detailed in the Aug. 11 edition of Scientific Reports.

    SLAC LCLS
    SLAC LCLS

    They measured natural motion in polystyrene samples heated to a gel-like middle ground between their melting point and solid state. This was the first demonstration that LCLS could be used for studying polymers and a whole range of other complex materials using a technique called X-ray photon correlation spectroscopy (XPCS),

    Hyunjung Kim of Sogang University in Korea, who led this research, said, “It was unknown whether the sample would survive the exposure to the ultrabright X-ray laser pulses. However, the X-ray damage effects on the sample were weaker than expected.”

    SLAC staff scientist Aymeric Robert said, “To see how you get from something that was completely moving to something completely static is very poorly understood. Observations of how polymers move in response to temperature changes and other effects can be compared with theoretical models to predict their behavior.” Robert oversees the experimental station at LCLS that is specially designed for this X-ray technique.

    “LCLS should allow scientists to measure motion in these materials in even more detail than possible using conventional X-ray tools,” he added.

    To study motion in the heated samples, researchers embedded a matrix of nanoscale gold spheres into the polymer. Then, they recorded sequences of up to about 150 X-ray images on different sections of the sample, with the delay between images ranging from as little as seven seconds to as much as 17 minutes.

    The XPCS technique measures successive “speckle” patterns that revealed subtle changes in the position of the gold spheres relative to one another – a measure of motion within the overall sample.

    While many experiments at LCLS capture X-ray data in the instant before samples are destroyed by the intense light, this technique allows some materials to survive the effects of many X-ray pulses, which is useful for studying longer-lived properties spanning from milliseconds to minutes.

    “We showed that we could study the complex dynamics in the polymer sample even at slow time scales,” Kim said. While this experiment proved that LCLS can be used to measure the long-duration motions across the entire sample, Kim said future experiments could vary the arrangement and size of the implanted gold spheres to better gauge motion at the scale of the molecular chains. Also, faster repetition of the X-ray laser pulses could help to study motion on a shorter time scale.

    In addition to Sogang University and SLAC’s LCLS, other participating researchers were from University of California, San Diego, Argonne National Laboratory; DESY lab, The Hamburg Center for Ultrafast Imaging and the University of Siegen, in Germany; Northern Illinois University; University of Massachusetts, Amherst; and Pohang Accelerator Laboratory (PAL) in Korea. The research was supported by the National Research Foundation funded by the Ministry of Science, ICT & Future Planning of Korea, and PAL in Korea, and the Department of Energy Office of Basic Energy Sciences.

    rig
    A view of the X-ray Correlation Spectroscopy experimental station at SLAC’s Linac Coherent Light Source (LCLS) X-ray laser. This station is designed to explore polymers and other hard-to-study materials. (SLAC National Accelerator Laboratory)

    graph
    This image (a) shows the experimental setup for an X-ray photon correlation spectroscopy experiment using polymer samples at SLAC’s Linac Coherent Light Source X-ray laser. (b) This transmission electron microscopy image shows nanoscale gold spheres that were embedded in a molten polymer to help study its motion. (c) This speckle pattern was produced as X-rays struck the polymer sample. A succession of these patterns show the changing positions of the gold spheres in the polymer sample, which provides a measure of the polymer’s motion. (10.1038/srep06017)

    image
    A computerized rendering of the X-ray Correlation Spectroscopy station at SLAC’s Linac Coherent Light Source X-ray laser, which was used to study motion in polymer samples. (SLAC National Accelerator Laboratory)

    See the full article here.

    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 1:14 pm on September 4, 2014 Permalink | Reply
    Tags: , , , X-ray Technology   

    From SLAC: “Scientists Map Protein in Living Bacterial Cells” 


    SLAC Lab

    September 3, 2014

    Experiment at SLAC’s X-ray Laser Opens Door to Exploring Cell Interiors

    Scientists have for the first time mapped the atomic structure of a protein within a living cell. The technique, which peered into cells with an X-ray laser, could allow scientists to explore some components of living cells as never before.

    The research, published Aug. 18 in Proceedings of the National Academy of Sciences, was conducted at the Department of Energy’s SLAC National Accelerator Laboratory.

    “This is a new way to look inside cells,” said David S. Eisenberg, a biochemistry professor at University of California, Los Angeles, and Howard Hughes Medical Institute investigator.

    “There are a lot of semi-ordered materials in cells where an X-ray laser could provide powerful information,” Eisenberg added. They include arrays in white blood cells that help to fight parasites and infections, insulin-containing structures in the pancreas and structures that break fatty acids and other molecules into smaller units to release energy.

    In the experiment at SLAC’s Linac Coherent Light Source X-ray laser, a DOE Office of Science User Facility, researchers probed a soil-dwelling bacterium, Bacillus thuringiensis or Bt, that is commonly used as a natural insecticide. Strains of this bacterium produce microscopic protein crystals and spores that kill insects. Normally scientists need to find ways to crystallize proteins in order to get their structures – typically a time-consuming, hit-and-miss process – but these naturally occurring crystals eliminated that step.

    SLAC LCLS Inside
    Inside the SLAC LCLS

    A liquid solution containing the living cells was jetted into the path of the ultrabright LCLS X-ray laser pulses. When a laser pulse struck a crystal, it created a pattern of diffracted X-ray light. More than 30,000 of these patterns were combined and analyzed by sophisticated software to reproduce the detailed 3-D structure of the protein.

    Many of the bacterial cells likely ruptured and spewed their crystal contents as they flew at high speed toward the X-rays. But because it took just thousandths of a second for the cells to reach the X-ray pulses, it’s very likely that many of the X-ray images showed protein crystals that were still inside the cells, the researchers concluded.

    three
    Three scenarios suggesting how the integrity of Bacillus thuringiensis (Bt) cells studied at the Linac Coherent Light Source X-ray laser might vary at the moment they are struck by X-rays. The horizontal arrow depicts the flow of the cell samples from a liquid jet to waste collection. The left, middle, and right columns depict three different time points along the liquid jet’s stream. Depending on the rate of cell rupture and the flow rate of the jet, the crystals may arrive at the interaction point either (1) inside intact cells, (2) inside ruptured (“lysed”) cells, or (3) outside of ruptured cells. (10.1073/pnas.1413456111)

    Importantly, Eisenberg said, “The rest of the cell contents don’t obscure the results.”

    In addition, the 3-D structure of proteins obtained from the crystals in living bacteria cells was essentially identical to that obtained through other methods. Earlier studies had already shown that LCLS can be used to study smaller, easier-to-produce crystals than traditional X-ray sources require, although it typically requires a far larger volume of crystals to achieve atomic-scale resolution.

    In an LCLS study published in 2012, a separate team of researchers used protein crystals grown inside live insect cells to study a potential weak spot in a parasite responsible for a disease called African sleeping sickness. But in that experiment they extracted the crystals rather than attempting to study them inside cells.

    Eisenberg said possible next steps include improving the technique by developing new sample-delivery methods that are gentler to the cells’ structure, and producing faster X-ray pulse rates that capture more images and yield even better results.

    “I think this whole area of science is going to continue growing,” he said.

    In addition to UCLA and LCLS, other researchers participating in the study were from Lawrence Berkeley National Laboratory; Arizona State University; University of California, Riverside; the Institute of Structural Biology in France; and the Max Planck Institute for Medical Research in Germany. The research was supported by the U.S. Department of Energy Office of Science, Howard Hughes Medical Institute, Max Planck Society, the National Institutes of Health, the Keck Foundation and the National Science Foundation.

    See the full article here.

    SLAC Campus
    SLAC is a multi-program laboratory exploring frontier questions in photon science, astrophysics, particle physics and accelerator research. Located in Menlo Park, California, SLAC is operated by Stanford University for the DOE’s Office of Science.
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  • richardmitnick 2:21 pm on August 29, 2014 Permalink | Reply
    Tags: , , Space Dust, X-ray Technology   

    From ANL: “Mysteries of space dust revealed” 

    News from Argonne National Laboratory

    August 29, 2014
    This story was originally reported by Kate Greene of Berkeley National Laboratory.

    The first analysis of space dust collected by a special collector onboard NASA’s Stardust mission and sent back to Earth for study in 2006 suggests the tiny specks open a door to studying the origins of the solar system and possibly the origin of life itself.

    NASA Stardust spacecraft
    NASA/Stardust

    This is the first time synchrotron light sources have been used to look at microscopic particles caught in the path of a comet. The Advanced Photon Source, the Advanced Light Source, and the National Synchrotron Light Source at the U.S. Department of Energy’s Argonne, Lawrence Berkeley and Brookhaven National Laboratories, respectively, enabled analysis that showed that the dust, which likely originated from beyond our solar system, is more complex in composition and structure than previously imagined.

    “Fundamentally, the solar system and everything in it was ultimately derived from a cloud of interstellar gas and dust,” says Andrew Westphal, physicist at the University of California, Berkeley’s Space Sciences Laboratory and lead author on the paper published this week in Science titled Evidence for interstellar origin of seven dust particles collected by the Stardust spacecraft. “We’re looking at material that’s very similar to what made our solar system.”

    The analysis tapped a variety of microscopy techniques including those that rely on synchrotron radiation. “Synchrotrons are extremely bright light sources that enable light to be focused down to the small size of these particles while providing unprecedented chemical identification,” said Hans Bechtel, principal scientific engineering associate at Berkeley Lab.

    The APS helped the researchers create a map of the locations and abundances of the different elements in each tiny particle, said Argonne physicist Barry Lai, who was involved with the analysis at the APS.

    “The Advanced Photon Source was unique in the capability to perform elemental imaging and analysis on such small particles — just 500 nanometers or less across,” Lai said. (That is so small that about 1,000 of them could fit in the period at the end of a sentence.) “This provided an important screening tool for differentiating the origin of each particle.”

    Researchers used the scanning transmission x-ray and Fourier transform infrared microscopes at the ALS. The X-ray microscope ruled out tens of interstellar dust candidates because they contained aluminum, not found in space or other substances and possibly knocked off the spacecraft and embedded in the aerogel. The infrared spectroscopy helped to identify sample contamination that could ultimately be subtracted later.

    “Almost everything we’ve known about interstellar dust has previously come from astronomical observations — either ground-based or space-based telescopes,” says Westphal. But telescopes don’t tell you about the diversity or complexity of interstellar dust, he says. “The analysis of these particles captured by Stardust is our first glimpse into the complexity of interstellar dust, and the surprise is that each of the particles are quite different from each other.”

    Westphal, who is also affiliated with Berkeley Lab’s Advanced Light Source, and his 61 co-authors, including researchers from the University of Chicago and the Chicago Field Museum of Natural History, found and analyzed a total of seven grains of possible interstellar dust and presented preliminary findings. All analysis was non-destructive, meaning that it preserved the structural and chemical properties of the particles. While the samples are suspected to be from beyond the solar system, he says, potential confirmation of their origin must come from subsequent tests that will ultimately destroy some of the particles.

    “Despite all the work we’ve done, we have limited the analyses on purpose,” Westphal explains. “These particles are so precious. We have to think very carefully about what we do with each particle.”

    Between 2000 and 2002, the Stardust spacecraft, on its way to meet a comet named Wild 2, exposed the special collector to the stream of dust coming from outside our solar system. The mission objectives were to catch particles from both the comet coma as well as from the interstellar dust stream. When both collections were complete, Stardust launched its sample capsule back to earth where it landed in northwestern Utah. The analyses of Stardust’s cometary sample have been widely published in recent years, and the comet portion of the mission has been considered a success.

    This new analysis is the first time researchers have looked at the microscopic particles collected en route to the comet. Both types of dust were captured by the spacecraft’s sample-collection trays, made of an airy material called aerogel separated by aluminum foil. Three of the space-dust particles (a tenth the size of comet dust) either lodged or vaporized within the aerogel while four others produced pits in the aluminum foil leaving a rim residue that fit the profile of interstellar dust.

    Much of the new study relied on novel methods and techniques developed specifically for handling and analyzing the fine grains of dust, which are more than a thousand times smaller than a grain of sand. These methods are described in twelve other papers available now and next week in the journal of Meteoritics & Planetary Science.

    One of the first research objectives was to simply find the particles within the aerogel. The aerogel panels were essentially photographed in tiny slices by changing the focus of the camera to different depths, which resulted in millions of images eventually stitched together into video. With the help of a distributed science project called Stardust@home [running on BOINC software from SSL], volunteer space enthusiasts from around the world combed through video, flagging tracks they believed were created by interstellar dust. More than 100 tracks have been found so far, but not all of these have been analyzed. Additionally, only 77 of the 132 aerogel panels have been scanned. Still, Westphal doesn’t expect more than a dozen particles of interstellar dust will be seen.

    The researchers found that the two larger dust particles from the aerogel have a fluffy composition, similar to that of a snowflake, says Westphal. Models of interstellar dust particles had suggested a single, dense particle, so the lighter structure was unexpected. They also contain crystalline material called olivine, a mineral made of magnesium, iron, and silicon, which suggest the particles came from disks or outflows from other stars and were modified in the interstellar medium.

    Three of the particles found in the aluminum foil were also complex, and contain sulfur compounds, which some astronomers believe should not occur in interstellar dust particles. Study of further foil-embedded particles could help explain the discrepancy.

    Westphal says that team will continue to look for more tracks as well as take the next steps in dust analysis. “The highest priority is to measure relative abundance of three stable isotopes of oxygen,” he says. The isotope analysis could help confirm that the dust originated outside the solar system, but it’s a process that would destroy the precious samples. In the meantime, Westphal says, the team is honing their isotope analysis technique on artificial dust particles called analogs. “We have to be super careful,” he says. “We’re doing a lot of work on analogs to practice, practice, practice.”

    The Advanced Photon Source is currently in the process of designing a proposed upgrade that would increase its ability to do such analyses, Lai said.

    “With the APS upgrade, we would be able to increase the spatial resolution and to image faster — effectively scanning a larger area of the aerogel in a shorter time,” he said.

    Since just over half of the aerogels have been checked for particles, there are plenty more waiting to be analyzed.

    This research was supported by NASA, the Klaus Tschira Foundation, the Tawani Foundation, the German Science Foundation, and the Funds for Scientific Research, Flanders, Belgium. In addition to ALS, the research made use of the National Synchrotron Light Source at Brookhaven National Laboratory and the Advanced Photon Source at Argonne. All three x-ray light sources are DOE Office of Science User Facilities.

    Brookhaven NSLS
    Brookhaven NSLS

    Berkeley Advanced Light Source
    LBL ALS

    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

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  • richardmitnick 3:34 pm on August 22, 2014 Permalink | Reply
    Tags: , , , X-ray Technology   

    From Brookhaven Lab: “A Single Diamond Crystal Does the Job” 

    Brookhaven Lab

    August 22, 2014
    Laura Mgrdichian

    X-ray absorption spectroscopy (XAS) is a technique used in many areas of science, from biology to materials science,that allows researchers to uncover information on a sample’s molecular structure and electronic behavior by studying how it absorbs and re-emits x-rays. Recently, a research team working at the National Synchrotron Light Source developed a way to improve certain XAS experiments by replacing a standard experimental component, an x-ray beam monitor, with a diamond-based type that is better performing but has been incompatible with many XAS experiments due to technical roadblocks.

    Brookhaven NSLS
    NSLS at Brookhaven

    x scans
    X-ray absorption spectroscopy (XAS) scans over energy ranges typical of XAS experiments

    The most common type of beam monitor is an ionization chamber, which consists of a gas-filled chamber between two charged electrodes. When x-rays pass through the gas, they ionize the molecules and cause a tiny but measurable current to flow between the electrodes. By calculating backward from the amount of current, researchers can determine the “flux” of the x-ray beam; that is, the total number of x-ray photons passing through a unit area as a function of the beam energy.

    Diamond sensors, which consist of a single diamond crystal, have many advantages over ionization chambers, including faster response times, less leakage current, and smaller size. But even as electronics-grade diamond is more readily available, they have not been commonly used in XAS because they respond poorly during experiments that require scanning over a large energy range. Often the range of the scan includes the Bragg diffraction energies for diamond – x-rays with wavelengths that are diffracted by the diamond rather than transmitted through it. (If the range of the energy scan avoids this value, then diamond sensors can simply be swapped out for ionization chambers.)

    “Measuring XAS data with a diamond sensor through an energy region that produces diffraction peaks yields data that require extensive post-processing,” said the study’s corresponding scientist, Bruce Ravel of the National Institute of Standards and Technology. “We have found a way that diamond sensors can be used, at least for certain XAS experiments, without having to do so much work to the data.”

    Ravel and his colleagues, from Stony Brook University, Brookhaven National Laboratory, and Case Western Reserve University, discovered that coupling the diamond sensor to an optic component known as a “half polycapillary lens” significantly mitigates the diffraction problem. The lens consists of a bundle of tiny glass tubes encased in a steel cylinder, with one end of the tubes drawn into a taper (in a full lens, both ends are tapered). The lens “smears” the x-ray beam before it reaches the diamond sensor, causing the diffraction effect to be far less pronounced.

    “The data we gathered using both the diamond sensor and the lens are of comparable quality as data taken using an ionization chamber and no lens,” said Ravel.

    The results of their investigation have led the group to propose combination devices, with a diamond window placed onto the end of the steel cylinder that encases the glass tubes, instead of the usual beryllium window.

    X-ray data for this study were collected at NSLS beamline X23A2. The paper describing the work is published in the October 2013 issue of Review of Scientific Instruments.

    See the full article here.

    One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world.Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.
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  • richardmitnick 4:09 pm on August 21, 2014 Permalink | Reply
    Tags: , , , X-ray Technology   

    From Berkeley Lab: “Researchers Map Quantum Vortices Inside Superfluid Helium Nanodroplets” 

    Berkeley Logo

    Berkeley Lab

    August 21, 2014
    Kate Greene

    Scientists have, for the first time, characterized so-called quantum vortices that swirl within tiny droplets of liquid helium. The research, led by scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the University of Southern California, and SLAC National Accelerator Laboratory, confirms that helium nanodroplets are in fact the smallest possible superfluidic objects and opens new avenues for studying quantum rotation.

    “The observation of quantum vortices is one of the most clear and unique demonstrations of the quantum properties of these microscopic objects,” says Oliver Gessner, senior scientist in the Chemical Sciences Division at Berkeley Lab. Gessner and colleagues, Andrey Vilesov of the University of Southern California and Christoph Bostedt of SLAC National Accelerator Laboratory at Stanford, led the multi-facility and multi-university team that published the work this week in Science.

    Droplet_art_fin3drop
    Illustration of analysis of superfluid helium nanodroplets. Droplets are emitted via a cooled nozzle (upper right) and probed with x-ray from the free-electron laser. The multicolored pattern (upper left) represents a diffraction pattern that reveals the shape of a droplet and the presence of quantum vortices such as those represented in the turquoise circle with swirls (bottom center). Credit: Felix P. Sturm and Daniel S. Slaughter, Berkeley Lab.

    The finding could have implications for other liquid or gas systems that contain vortices, says USC’s Vilesov. “The quest for quantum vortices in superfluid droplets has stretched for decades,” he says. “But this is the first time they have been seen in superfluid droplets.”

    Superfluid helium has long captured scientist’s imagination since its discovery in the 1930s. Unlike normal fluids, superfluids have no viscosity, a feature that leads to strange and sometimes unexpected properties such as crawling up the walls of containers or dripping through barriers that contained the liquid before it transitioned to a superfluid.

    Helium superfluidity can be achieved when helium is cooled to near absolute zero (zero kelvin or about -460 degrees F). At this temperature, the atoms within the liquid no longer vibrate with heat energy and instead settle into a calm state in which all atoms act together in unison, as if they were a single particle.

    For decades, researchers have known that when superfluid helium is rotated–in a little spinning bucket, say–the rotation produces quantum vortices, swirls that are regularly spaced throughout the liquid. But the question remained whether anyone could see this behavior in an isolated, nanoscale droplet. If the swirls were there, it would confirm that helium nanodroplets, which can range in size from tens of nanometers to microns, are indeed superfluid throughout and that the motion of the entire liquid drop is that of a single quantum object rather than a mixture of independent particles.

    But measuring liquid flow in helium nanodroplets has proven to be a serious challenge. “The way these droplets are made is by passing helium through a tiny nozzle that is cryogenically cooled down to below 10 Kelvin,” says Gessner. “Then, the nanoscale droplets shoot through a vacuum chamber at almost 200 meters-per-second. They live once for a few milliseconds while traversing the experimental chamber and then they’re gone. How do you show that these objects, which are all different from one another, have quantum vortices inside?”

    og
    Oliver Gessner, Chemical Sciences Division, Berkeley Lab. Credit: Roy Kaltschmidt

    The researchers turned to a facility at SLAC called the Linac Coherent Light Source (LCLS), a DOE Office of Science user facility that is the world’s first x-ray free-electron laser. This laser produces very short light pulses, lasting just a ten-trillionth of a second, which contain a huge number of high-energy photons. These intense x-ray pulses can effectively take snapshots of single, ultra-fast, ultra-small objects and phenomena.

    slac
    Inside the SLAC LCLS

    “With the new x-ray free electron laser, we can now image phenomenon and look at processes far beyond what we could imagine just a decade ago,” says Bostedt of SLAC. “Looking at the droplets gave us a beautiful glimpse into the quantum world. It really opens the door to fascinating sciences.”

    In the experiment, the researchers blasted a stream of helium nanodroplets across the x-ray laser beam inside a vacuum chamber; a detector caught the pattern that formed when the x-ray light diffracted off the drops.

    The diffraction patterns immediately revealed that the shape of many droplets were not spheres, as was previously assumed. Instead, they were oblate. Just as the Earth’s rotation causes it to bulge at the equator, so too do rotating nanodroplets expand around the middle and flatten at the top and bottom.

    But the vortices themselves are invisible to x-ray diffraction, so the researchers used a trick of adding xenon atoms to the droplets. The xenon atoms get pulled into the vortices and cluster together.

    “It’s similar to pulling the plug in a bathtub and watching the kids’ toys gather in the vortex,” says Gessner. The xenon atoms diffract x-ray light much stronger than the surrounding helium, making the regular arrays of vortices inside the droplet visible. In this way, the researchers confirmed that vortices in nanodroplets behave as those found in larger amounts of rotating superfluid helium.

    Armed with this new information, the researchers were able to determine the rotational speed of the nanodroplets. They were surprised to find that the nanodroplets spin up to 100,000 times faster than any other superfluid helium sample ever studied in a laboratory.

    Moreover, while normal liquid drops will change shape as they spin faster and faster–to resemble a peanut or multi-lobed globule, for instance–the researchers saw no evidence of such shapeshifting in the helium nanodroplets. “Essentially, we’re exploring a new regime of quantum rotation with this matter,” Gessner says.

    “It’s a new kind of matter in a sense because it is a self-contained isolated superfluid,” he adds. “It’s just all by itself, held together by its own surface tension. It’s pretty perfect to study these systems if one wants to understand superfluidity and isolate it as much as possible.”

    This research was supported by the DOE Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Division as well as the National Science Foundation.

    See the full article here.

    A U.S. Department of Energy National Laboratory Operated by the University of California

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