Lightsources.org

Plant roots police toxic pollutants

2018/08/062018/08/09

X-ray studies reveal details of how P. juliflora shrub roots scavenge and immobilize arsenic from toxic mine tailings.

Working in collaboration with scientists at the U.S. Department of Energy’s Brookhaven National Laboratory and SLAC National Accelerator Laboratory, researchers at the University of Arizona have identified details of how certain plants scavenge and accumulate pollutants in contaminated soil. Their work revealed that plant roots effectively “lock up” toxic arsenic found loose in mine tailings—piles of crushed rock, fluid, and soil left behind after the extraction of minerals and metals. The research shows that this strategy of using plants to stabilize pollutants, called phytostabilization, could even be used in arid areas where plants require more watering, because the plant root activity alters the pollutants to forms that are unlikely to leach into groundwater.

The Arizona based researchers were particularly concerned with exploring phytostabilization strategies for mining regions in the southwestern U.S., where tailings can contain high levels of arsenic, a contaminant that has toxic effects on humans and animals. In the arid environment with low levels of vegetation, wind and water erosion can carry arsenic and other metal pollutants to neighboring communities.

Image: Scientists from the University of Arizona collect plant samples from the mine tailings at the Iron King Mine and Humboldt Smelter Superfund site in central Arizona. X-ray studies at Brookhaven Lab helped reveal how these plants’ roots lock up toxic forms of arsenic in the soil.
Credit: Jon Chorover

SESAME hosts its first users

2018/08/032018/08/09

Mid July, the first users arrived at SESAME to perform experiments using the Centre’s XAFS/XRF (X-ray absorption fine structure/X-ray fluorescence) spectroscopy beamline, SESAME’s first beamline to come into operation.

This was the Finnish Kirsi Lorentz and three of her colleagues at The Cyprus Institute: the Cypriot Grigoria Ioannou, the Japanese Yuko Miyauchi and the Greek/Egyptian Iosif Hafez, who together form a true international team in the spirit of SESAME.

Kirsi is the author of one of the 19 proposals from 5 of the SESAME Members (Cyprus, Egypt, Jordan, Pakistan and Turkey) that have been recommended for a total of 95.8 hour shifts on the XAFS/XRF beamline by SESAME’s Proposal Review Committee (PRC). The PRC is an international advisory body that evaluates the scientific and technological merit of proposals from the General Users and determines their priority using criteria based on IUPAP’s Recommendations for the Use of Major Physics Users Facilities.

“This heralds in a new stage in SESAME’s march forward, and for scientists in the SESAME Members and the region it is the tangible beginning of a moment from when it becomes possible to carry out state-of-the-art research in the region” said Khaled Toukan, Director of SESAME.

“It is a unique opportunity and a real honour to be the first user of a synchrotron light facility – a research visit to remember” said Kirsi, who is examining ancient human remains from the Eastern Mediterranean and the Near East, adding “we are very excited with the results we obtained at the SESAME XAFS/XRF beamline, and grateful to all those who have worked so hard to bring this crucial research facility into operation in our region”.

>Read more on the SESAME website

Picture: Kirsi Lorentz, The Cyprus Institute: Kirsi Lorentz and her research team (from left to right: Yuko Miyauchi, Grigoria Ioannou, Kirsi Lorentz and Iosif Hafez) at the XAFS/XRF beamline control hutch.

Demonstrating a new approach to lithium-ion batteries

2018/08/032018/08/06

A team of researchers from the University of Cambridge, Diamond Light Source and Argonne National Laboratory in the US have demonstrated a new approach that could fast-track the development of lithium-ion batteries that are both high-powered and fast-charging.

In a bid to tackle rising air pollution, the UK government has banned the sale of new diesel and petrol vehicles from 2040, and the race is on to develop high performance batteries for electric vehicles that can be charged in minutes, not hours. The rechargeable battery technology of choice is currently lithium-ion (Li-ion), and the power output and recharging time of Li-ion batteries are dependent on how ions and electrons move between the battery electrodes and electrolyte. In particular, the Li-ion diffusion rate provides a fundamental limitation to the rate at which a battery can be charged and discharged.

Synchrotron light to study how sun radiation damages skin and hair

2018/08/02

Researchers from the Institute of Advanced Chemistry of Catalonia (IQAC-CSIC) are investigating damage on skin and hair caused by ultraviolet sunlight. They have profited from the ALBA Synchrotron technology to see with high resolution and accurate detail the changes occurring at molecular level, not only at the surface of skin and hair, but also in their inner layers. The samples were previously treated with resveratrol, well-known antioxidant, to evaluate how effective is to develop new and better photoprotective treatments.

>Read more on the ALBA website

High-caliber research launches NSLS-II beamline into operations

2018/08/012018/08/09

Pratt & Whitney conduct the first experiments at a new National Synchrotron Light Source II beamline.

A new experimental station (beamline) has begun operations at the National Synchrotron Light Source II (NSLS-II)—a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory. Called the Beamline for Materials Measurement (BMM), it offers scientists state-of-the-art technology for using a classic synchrotron technique: x-ray absorption spectroscopy.

“There are critical questions in all areas of science that can be solved using x-ray absorption spectroscopy, from energy sciences and catalysis to geochemistry and materials science,” said Bruce Ravel, a physicist at the National Institute of Standards and Technology (NIST), which constructed and operates BMM through a partnership with NSLS-II.

X-ray absorption spectroscopy is a research technique that was developed in the 1980s and, since then, has been at the forefront of scientific discovery.

“The reason we’ve used this technique for 40 years and the reason why NIST built the BMM beamline is because it adds a great value to the scientific community,” Ravel explained.

The first group of researchers to conduct experiments at BMM came from jet engine manufacturer Pratt & Whitney. Senior Engineer Chris Pelliccione and colleagues used BMM to study the chemistry of jet engines.

Image: Pratt & Whitney Senior Engineer Chris Pelliccione (left) with NIST’s Bruce Ravel (right) at BMM’s workstation.

Scientists unravel mechanism for body odour in armpits

2018/08/012018/08/09

British researchers from the University of York and the University of Oxford have shown the mechanism that leads to body odour in armpits by studying the molecular process at the ESRF and other lightsources.

Stepping into a cramped bus on a hot summer day can sometimes translate into having to hold your breath and a very unpleasant experience. Sweat production increases in hot weather, and, with it, body odour. Despite much research and antiperspirant deodorants, scientists still haven’t managed to selectively block body odour.

Researchers from the University of York and the University of Oxford have recently used the ESRF and Diamond Lightsource to find out what happens at a molecular level when we smell badly. They focused on the apocrine gland, which is found only in the armpit, genitalia and ear canal. It secrets an odourless lipid-rich viscous secretion, which is likely to play a role in scent generation, but it is not involved in thermoregulation.

It all comes down to bacteria. “The skin of our underarms provides a unique niche for bacteria,” explains investigator Gavin Thomas, professor in the department of biology at the University of York and co-leader of the study. “Through the secretions of various glands that open onto the skin or into hair follicles, this environment is nutrient-rich and hosts its own microbial community, the armpit microbiome, of many species of different microbes.”

Image: Picture showing how body odour is produced in armpits.
Credit: University of York and Oxford.

Insight into catalysis through novel study of X-ray absorption spectroscopy

2018/07/312018/08/07

An international team has made a breakthrough at BESSY II.

For the first time, they succeeded in investigating electronic states of a transition metal in detail and drawing reliable conclusions on their catalytic effect from the data. These results are helpful for the development of future applications of catalytic transition-metal systems. The work has now been published in Chemical Science, the Open Access journal of the Royal Society of Chemistry.

Many important processes in nature depend on catalysts, which are atoms or molecules that facilitate a reaction, but emerge from it themselves unchanged. One example is photosynthesis in plants, which is only possible with the help of a protein complex comprising four manganese atom sites at its centre. Redox reactions, as they are referred to, often play a pivotal role in these types of processes. The reactants are reduced through uptake of electrons, or oxidized through their release. Catalytic redox processes in nature and industry often only succeed thanks to suitable catalysts, where transition metals supply an important function.

Image: Manganese compounds also play a role as catalysts in photosynthesis.
Credit: HZB

Understanding reaction pathways leading to MnO2 polymorph formation

2018/07/312018/09/05

Computational driven design of materials has provided guidelines for designing novel materials with desired properties, especially for metastable materials, which may have superior functionalities than its stable counterparts [1]. However, the synthesis of these metastable materials is usually challenging. The current computational approaches are not able to predict reaction pathways passing through intermediate or metastable phases. As a consequence, the synthesis of many compounds still remains Edisonian, meaning that repeated iteration is usually required to find the reaction conditions needed for synthesizing targeted materials with desired properties. To reduce the amount of cost and effort during this discovery process, a predictive theory for directing the synthesis of materials is necessary.

In the recent article “Understanding Crystallization Pathways Leading to Manganese Oxide Polymorph Formation [2]”, researchers from SLAC, LBNL, MIT, Colorado School of Mines, and NREL combined theory and experimental approaches to develop and demonstrate a theoretical framework that guides the synthesis of intermediate/metastable phases. This ab initio-computation based framework calculates the influence of particle size and solution composition on the stability of polymorph (substances having the same composition but different crystallographic structures), and predicts the phases that will appear along the different reaction pathways.

>Read more on the SSRL at SLAC website

Image (extract): (a) Size-dependent phase diagram of MnO₂polymorphs. The three arrows mark the reaction progression from nano-size to bulk at different potassium concentrations. (b-d) The evolution of x-ray scattering pattern with time along [K⁺] = 0 M (b), 0.2 M (c), and 0.33M (d). The identities and the fractions of the phases are marked in the subfigure to the right. (e-f) Electron beam diffraction patterns of the δ” phase and δ’ phase harvested from [K⁺] = 0 M and 0.2 M, respectively. See all figures here.

Microfluidic mixing chips can reveal how biomolecules interact

2018/07/312018/09/05

Christopher Flynn, a fourth year student majoring in Physics and Mathematics at Fort Lewis College, and a SUnRiSE student at Cornell this summer, is contributing to the design of microfluidic mixing chips which could significantly enhance our understanding of proteins and living cells.

Microfluidic mixing chips are used by scientists to analyze biological molecules. They have small channels in which biological solutions, usually solutions of protein, are mixed. Biological small angle x-ray solution scattering (BioSAXS) is then used to study how these biomolecules change under different conditions, for example when they mix with hormones and drugs or when they interact with other biomolecules. These observations can help further our understanding of how cells function.

With the intention of opening a door to the inner workings of cells, Flynn and Gillilan are continuing the work of Gillilan’s former postdoctoral student, Jesse Hopkins, who started a project on microfluidic chips more than two years ago. Hopkins was working on fabricating chips that could be used to observe molecular interactions and structural changes on a millisecond scale.

While Hopkins successfully designed almost every aspect of the chip, he was unable to get the final x-ray transparent window fixed on the chip without it leaking. Flynn’s main task over the summer is to resolve this. He creates chips in the Cornell NanoScale Science and Technology Facility (CNF), using techniques including photolithography and lamination. The chips have different layers, the faulty transparent window being in one of the last. After the first few layers of the chips are made, Flynn uses them to investigate different possibilities for the window. He expects to test these windows by pumping liquids through the chips, and if they have been fit successfully, to compare any results to computer simulations that Hopkins had developed.

Image: Richard Gillilan and Topher Flynn. The channels of the mixing chips are 30 microns wide, 500 microns deep.; a difficult feat but important feature of the chip.

Shutdown BESSY II: work has started

2018/07/302018/08/06

As of 30 July 2018, BESSY II will be down for several weeks.

In the summer shutdown, important components in the storage ring tunnel will be replaced and overhauled. The first conversion work for the BESSY VSR project also begins. Upgrading BESSY II into a variable-pulse-length storage ring (BESSY-VSR) will provide unique experimental conditions for researchers worldwide. The shutdown lasts until 30 September 2018, and user operation will recommence on 30 October 2018.

While the ring is down, the HZB employees will be completely modifying the multipole wavelength shifter, the EDDI beamline and the radiation protection hutches. This space will be needed for installing the cold supply for the superconducting cavities in the storage ring. These are key components in the creation of BESSY VSR. Keeping them cold, however, requires an elaborate infrastructure, which is to be built up in the experimental hall over the next two years.

You can take a detailed look at everything that will be going on during the shutdown in the HZB Science Blog

Picture: The experimental hall of Bessy II.
Credit: HZB / D.Butenschön

MEDSI 2018

2018/07/282018/11/29

The MEDSI 2018 took place in June 2018.

The Synchrotron SOLEIL was proud to welcome you to the 10th edition of the Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation (MEDSI) conference from 25 to 29 June 2018.

Find here all the relevant documents related to this conference:

LINK TO PDF

Printing nerve scaffolds

2018/07/272018/08/06

Engineering 3D bio-printed scaffolds to help regenerate damaged peripheral nervous systems

In the last decade or so, 3D printing has experienced a surge in popularity as the technology has become more precise and accessible. Now, researchers from the University of Saskatchewan are looking at how we can use 3D printing to help damaged nervous systems to regrow.

The peripheral nervous system, which controls the body beyond the brain and the spinal cord, can be damaged by poor diet, toxins, and trauma. It can also be damaged by diseases such as diabetes, which affects about 422 million people worldwide, and 3.4 million people in Canada.

Damage to the peripheral nervous system can affect our sense of touch and our motor control. The current standard for treating large gaps in the nervous system due to damage is nerve autografts, where donor nerves from another part of the body are used to repair the damaged parts.

Image: The tiny, bio-printed scaffolds are less than a centimeter long on each side.

A designed material untangles long-standing puzzle

2018/07/242018/08/06

This approach could lead to new materials with emergent physics and unique electronic properties, supporting broader research efforts to revolutionize modern electronics.

When atoms or molecules assemble to form bulk matter, new properties (such as conductivity and ferromagnetism) that didn’t exist in the constituent parts can emerge from the whole. Similarly, stacking atomically thin layers into nanostructures (heterostructures) can give rise to a rich variety of emergent phases not found in bulk materials.

Materials that exhibit emergent phenomena (“quantum materials”) often feature multiple phases with simultaneous phase transitions. A great deal of effort is currently being expended to disentangle such transitions, to discover what drives them and to ultimately harness them in new materials with desired functionalities. Most of these efforts have relied on external perturbations (light, pressure, etc.) to decouple the transitions. In this work, researchers found a way to do this intrinsically, through layer-by-layer design of stacking sequences with mismatched periodicities.

Image: (a) Rare-earth (RE) nickelates (RENiO₃) host multiple types of entangled orderings. This illustration depicts a magnetic ordering (spin directions indicated by yellow arrows) and a charge ordering (a checkerboard of two nickel oxidation states, indicated by sphere size and color) in bulk RENiO₃ (RE and O atoms omitted for clarity).
Please find the entire image here.

Pressure tuning of light-induced superconductivity in K3C60

2018/07/242018/09/03

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological application is hindered by their low operating temperature, which in the best case can reach -70 degrees Celsius. Researchers of the group of Prof. A. Cavalleri at the Max Planck Institute of the Structure and Dynamics of Matter (MPSD) in Hamburg have routinely used intense laser pulses to stimulate different classes of superconducting materials. Under specific conditions, they have detected evidences of superconductivity at unprecedented high temperatures, although this state persisted very shortly, just for a small fraction of a second.
An important example is that of K₃C₆₀, an organic molecular solidformed by weakly-interacting C60 “buckyball” molecules (60 carbon atoms bond in the shape of a football),which is superconducting at equilibrium below a critical temperature of -250 degrees Celsius. In 2016, Mitrano and coworkers at the MPSD discovered that tailored laserpulses, tuned to induce vibrations of the C60 molecules,can induce a short-lived, highly conducting state with properties identical to those of a superconductor, up to a temperature of at least -170 degrees Celsius, far higher than the equilibrium critical temperature (Mitrano et al., Nature, 530, 461–464 (2016)).

In their most recent investigation, A. Cantaluppi, M. Buzzi and colleagues at MPSD in Hamburg went a decisive step further by monitoring the evolution of the light-induced state in K₃C₆₀ once external pressure was applied by a diamond anvil cell (Figure 1). At equilibrium, when pressure is applied, the C₆₀ molecules in the potassium-doped fulleride are held closer to each other. This weakens the equilibrium superconducting state and significantly reduces the critical temperature. The steady state optical response of K₃C₆₀at different pressures and temperatures was determined via Fourier-transform infrared spectroscopy, by exploiting the high brightness of the synchrotron radiation available at the infrared beamline SISSI at Elettra.

>Read more on the Elettra website

Image: Light-induced superconductivity in K₃C₆₀ was investigated at high pressure in a Diamond Anvil Cell.
Credit: Jörg Harms / MPSD

Open and shut: pain signals in nerve cells

2018/07/232018/07/24

Our daily function depends on signals traveling between nerve cells (neurons) along fine-tuned pathways. Central nervous system neurons contain acid-sensing ion channel 1a (ASIC1a), a protein important in sensing pain and forming memories of fear. An ion channel lodged in the cell membrane that provides a pathway for sodium ions to enter the cell, ASIC1a opens and closes in response to changes in extracellular proton concentrations. When protons accumulate outside the neuron, the channel opens, allowing sodium ions to flow into the cell, depolarizing the cell membrane and generating an electrical signal. The channel eventually becomes desensitized to protons and the gate closes. Scientists have visualized both the open and desensitized channel structures, but the third structure, which forms when the protons dissipate and the channel closes, remained elusive. Using protein crystallography at the ALS, researchers finally visualized the closed channel.

Animation: As the proton concentration increases or decreases, the gated channel ASIC1a toggles between open and closed positions, controlling the timing of signals traveling through the cell membrane of one neuron en route to the next.

Structures reveal new target for malaria vaccine

2018/07/202018/08/06

The discovery paves the way for the development of a more effective and practical human vaccine for malaria, a disease responsible for half a million deaths worldwide each year.

Malaria kills about 445,000 people a year, mostly young children in sub-Saharan Africa, and sickens more than 200 million. It’s caused by a parasite, Plasmodium falciparum (Pf), and is spread to humans through the bite of an infected Anopheles mosquito.

The parasite’s complex life cycle and rapid mutations have long challenged vaccine developers. Only one experimental vaccine, known as RTS,S, has progressed to a Phase 3 clinical trial (testing on large groups of people for efficacy and safety). To elicit an immune response, this vaccine uses a fragment of circumsporozoite protein (CSP), which covers the malaria parasite in its native conformation. However, the trial results showed that RTS,S is only moderately effective, protecting about one-third of the young children who received it over a period of four years.

Image (a) Left: Surface representation of CIS43 (light chain in tan and heavy chain in light blue), with peptide 21 shown as sticks (purple). Right: A 90° rotation of the representation. See entire image here.