#SyncroLightAt75 – Structure of the Ribosome

Along with Ada Yonath and Thomas Steitz,Venkatraman Ramakrishnan from the MRC Laboratory of Molecular Biology in Cambridge, UK was awarded the 2009 Nobel Prize in Chemistry for determining the structure of the ribosome, one of the largest and most important molecules in the cell. X-ray crystallography experiments that enabled elucidation of the ribosome structure used synchrotron light from a number of light sources worldwide, each with unique capabilities, including the Swiss Light Source SLS.

Read more on the PSI website

Image: Interior view of the experimental hall at the Swiss Light Source SLS

Credit: Photo: H.R. Bramaz/PSI

Nanoparticles made from marine polymers for cutaneous drug delivery applications

A research led by the University of Porto in collaboration with the ALBA Synchrotron has studied for the first time the interaction of nanoparticles with the skin, using synchrotron light at the MIRAS beamline. The findings unveil the role of the different skin components and the mechanism of the permeation enhancement conferred with nanoparticles, made from marine polymers. A nano delivery system application in the skin will reduce the dosage needed due to controlled drug delivery and allow newer and better-targeting therapeutic strategies towards cutaneous administration.

Cutaneous drug delivery allows the administration of therapeutic and cosmetic agents through the skin. Advantages of this administration route include high patient compliance, avoidance of high concentration levels of the drug when reaching systemic circulation, and far fewer side effects compared to other administration routes.

Still, the peculiar skin structure assures protection to the human organism and hampers drug delivery. To overcome this issue, skin permeation enhancers, such as nanoparticles, can be used. They are pharmacologically inactive molecules that can increase skin permeability by interacting with the stratum corneum, the first layer of the epidermis, which is the outermost layer of the skin. However, the mechanisms of nanoparticles’ interaction with the skin structure are still unknown.

A research project led by the University of Porto (Portugal) in collaboration with the ALBA Synchrotron has studied for the first time the interaction of polymeric nanoparticles with the skin, using synchrotron light.

Read more on the ALBA website

Image: Nanoparticles made visible on human skin – 3D Rendering

Credit: Adobe Stock

Innovative fuels for Small Modular Reactors

If Canada is to meet its target of net-zero emissions by 2050, our country must transition to a diverse, innovative range of alternative sources of energy.

Mouna Saoudi, a materials scientist at Canadian Nuclear Laboratories (CNL), is using the Canadian Light Source at the University of Saskatchewan to explore how advanced nuclear fuels for small modular reactors (SMRs) could be used to help fill the gap between fossil fuels and renewables.

“SMRs would be an efficient way to reach net zero by 2050, which is an ambitious but hopefully achievable goal,” says Saoudi.

SMRs can power electrical grids, provide process heat, and offer energy solutions for various industries — such as remote mining operations.

Saoudi is currently investigating how types of advanced nuclear fuels behave under different reactor conditions.

“My main focus is characterization of advanced nuclear fuels for potential use in small modular reactors,” Saoudi says.

The advanced fuels combine uranium oxide — the main element used in nuclear fuel for decades —with the naturally occurring and abundant element thorium in oxide form. Saoudi says that there are many advantages to mixing the two elements, including increased efficiency and better in-reactor performance.

Using the HXMA beamline, Saoudi was able to confirm the similar distribution of the two elements, uranium and thorium, in the mixed fuel oxides. Saoudi believes this was the first time the CLS has been used for this type of study.

Saoudi has been working with USask researcher Andrew Grosvenor from the Department of Chemistry. Their findings were recently published in the Journal of Nuclear Materials.

The CLS allowed Saoudi and her collaborators to investigate the electronic and local structure of the fuel — crucial information needed to identify the optimum fuel composition that would have better in-reactor performance than that of uranium oxide.

Read more on the CLS website

Image: (Left to right) Dr. Than Do, Dr. Mouna Saoudi, and Dr. Julien Lang, R&D scientists at Canadian Nuclear Laboratories (CNL).

Ultrafast all-optical spin injection in silicon revealed at FERMI

A revolutionary and energy-efficient information technology encoding digital data in electron spin (spintronics) by combining semiconductors and ferromagnets is being developed worldwide. Merging of memory and logic computing of magnetic based storage devices and silicon-based logic transistors is expected to ultimately lead to new computing paradigms and novel spin-based multifunctional devices. The advantages of this new technology would be non-volatility, increased data processing speed, reduced electric power consumption. All of them are essential steps towards next generation quantum computers.

To create spin-based electronics with potential to revolutionize information technology, silicon, the predominant semiconductor, needs to be integrated with spin functionality. Although silicon is non-magnetic at equilibrium, spin polarized currents can be established in Si by a variety of approaches such as the use of polarized light, hot electrons spin injection, tunnel spin injection, Seebeck spin tunneling and dynamical spin pumping methods, as had been demonstrated recently. In general, spin polarized currents refer to the preferential alignment of the spin angular momentum of the electrons in a particular direction.

Read more on the Elettra website

Image: Figure 1: a) the optical generation of spin polarized superdiffusive currents across a ferromagnetic/semiconductor interface is illustrated. b) the principles of TR-MOKE experiment are illustrated  together with a cross-section TEM image describing the quality of the Ni/Si interface.

Cellulose-based actuators can be programmed and repair themselves

Smart gifts will soon unwrap themselves

With the help of the high-brilliance X-ray source PETRA III, a German-Swedish research group has developed a new cellulose polymer material that can be specifically animated to move by moisture, making it an ideal base material for programmable actuators. In addition, the composite material is also very resistant to stretching and able to repair itself, as the group reports in the scientific journal “Advanced Functional Materials”. The mechanism of this self-healing in particular was investigated at PETRA III.

n nature, fascinating functions and mechanisms have prevailed over millions of years of evolution. In bionics research, scientists try to copy and reproduce these efficient methods from nature. For example, in sensors or bionic actuators, active elements that – controlled by a signal – can switch or move something. Modern actuators should be programmably stimulable, very robust and able to cope with a wide range of working conditions.

The research team with members from the Royal Institute of Technology Stockholm (KTH), DESY and the Helmholtz Centre for Heavy Ion Research has now produced a thin film of cellulose nanofibres with two types of polymers, following the example of biological tissue. To do this, they mixed polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS) with the cellulose fibrils and poured the solution onto a glass plate. When it dried out, a circular film was formed in which a tight network of chemical and physical bonds formed. “It is the polystyrene sulphonate in particular that makes the film extremely stretchable and tough,” says DESY scientist Qing Chen, first author of the study. “This ingredient of the solution can be broadened by mixing food colouring agents, thus making it more colourful and diverse.”

Pieces up to several centimetres in size can be cut out of this film, which bend when exposed to moisture. “In principle, we can make an active wrapping paper out of the material,” says Stephan Roth (DESY and KTH), head of the PETRA III beamline P03 and co-author of the study, “you just have to spray some moisture on it, and it unwraps itself.”

Read more on the DESY website

Image: The cellulose polymer actuators can be used for a variety of purposes.

Credit: DESY, Qing Chen

Formation of the defect dipoles around dopants demonstrated in dielectric ceramics

A team of international scientists from China, Germany, Norway and Pakistan with SESAME staff have used the BM08 – XAFS/XRF beamline at SESAME for high dielectric constant materials that are of particular interest as indispensable components in electronics. The authors have demonstrated a new approach for optimizing the dielectric properties by acceptor–donor co-doping in (Gax, Cuy) Zn1−x–yO films fabricated with pulse laser deposition (PLD) or, alternatively, exchanging the co-doping step by ion implantation. Exploitation of defect engineering in dielectric ceramics for enhancing performance is an active research area globally. Materials with high dielectric constant (k) and low loss throughout a wide frequency range are among the key components for the device size scale-down in nanoelectronics. The XAFS study performed at SESAME revealed the formation of the defect dipoles around dopants.

Read more on the SESAME website

Image: Examples of the X-ray analysis. a) XPS data showing the Cu 2p spectra for the Cu8Zn92O and Ga0.5Cu8Zn91.5O films. b) The X-ray absorption near edge structure (XANES) spectra at the Cu K-edge of Cu8Zn92O and Ga0.5Cu8Zn91.5O samples including reference samples, e.g., Cu foil and CuO powder. c) Magnitude of the Fourier transform of the extended X-ray absorption fine structure (EXAFS) spectra. d) Fourier transform of Real χ at the Zn K-edge of Ga0.5Zn99.5O, Cu8Zn92O, and Ga0.5Cu8Zn91.5O samples compared with theoretical model (black lines).

Advanced Light Source upgrade approved to start construction

Berkeley Lab’s biggest project in three decades now moves from planning to execution. The ALS upgrade will make brighter beams for research into new materials, chemical reactions, and biological processes.

The Advanced Light Source (ALS), a scientific user facility at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), has received federal approval to start construction on an upgrade that will boost the brightness of its X-ray beams at least a hundredfold.

“The ALS upgrade is an amazing engineering undertaking that is going to give us an even more powerful scientific tool,” said Berkeley Lab Director Michael Witherell. “I can’t wait to see the many ways researchers use it to improve the world and tackle some of the biggest challenges facing society today.”

Scientists will use the upgraded ALS for research spanning biology; chemistry; physics; and materials, energy, and environmental sciences. The brighter, more laser-like light will help experts better understand what’s happening at extremely small scales as reactions and processes take place. These insights can have a huge array of applications, such as improving batteries and clean energy technologies, creating new materials for sensors and computing, and investigating biological matter to develop better medicines.

“That’s the wonderful thing about the ALS: The applications are so broad and the impact is so profound,” said Dave Robin, the project director for the ALS upgrade. “What really excites me every day is knowing that, when it’s complete, the ALS upgrade will enable researchers to make scientific advances in many different areas for the next 30 to 40 years.”

The DOE approval, known as Critical Decision 3 (CD-3), formally releases funds for purchasing, building, and installing upgrades to the ALS. This includes constructing an entirely new storage ring and accumulator ring, building four feature (two new and two upgraded) beamlines, and installing seismic and shielding upgrades for the concrete structure housing the equipment. The $590 million project is the biggest investment at Berkeley Lab since the ALS was built in 1993.

Read more on the Berkeley Laboratory website

Image: The upgrade to the Advanced Light Source at Berkeley Lab will add two new particle accelerator rings within the iconic building’s footprint. 

Credit: Thor Swift/Berkeley Lab

Watching nanoparticle chemistry and structure evolve

Using a multimodal approach developed at the Advanced Light Source (ALS), researchers learned how chemical properties correlate with structural changes during nanoparticle growth.

The work will enable a greater understanding of the mechanisms affecting the durability of nanoparticles used to catalyze a broad range of chemical reactions, including clean-energy reactions.

Catalyzing technological progress

In applications ranging from chemical synthesis to energy storage, catalysts enable chemical reactions to run at more favorable temperatures, pressures, or in general, with lower energy requirements. For example, catalysts enable the efficient splitting of water to generate hydrogen, which can then be used as a clean, decarbonized fuel.

For such applications, nanoparticles on the surface of a transition-metal oxide work well as catalysts, but they are susceptible to coarsening, agglomeration, and other forms of degradation, shortening their usable lifetime. In this work, researchers applied a technique they developed at the ALS to simultaneously study the chemistry and structure of catalyst materials as they form, a capability that will help scientists identify strategies for improving nanoparticle durability.

Understanding nanoparticle exsolution

A process called “exsolution” has shown significant promise for controlling nanoparticle size, shape, distribution, and stability. Briefly, the process involves causing dopant atoms in a host matrix to migrate to the surface and gather to form nanoparticles. This is done by heating the host material under reducing conditions (i.e., in a reducing gas such as hydrogen). Exsolution from metal oxide hosts produces highly stable metal nanoparticles that are often partially embedded in the oxide surface and show high activity for the oxygen evolution reaction (OER), a key step in many electrochemical reactions, including water splitting.

Here, the samples studied were thin films of SrTi0.9Nb0.05Ni0.05O3-δ (STNNi). When STNNi is heated in H2 gas, the Ni atoms migrate to the surface and form nanoparticles. Before the reducing treatment, such samples are inactive with respect to the OER. After treatment, the system becomes active, despite a relatively small amount of Ni doping.

Read more on the ALS website

Image: Atomic force microscope images of nickel- and niobium-co-doped strontium titanate, before (left) and after (right) thermal treatment in a reducing (H2) atmosphere. After treatment, bright features consistent with the formation of nickel nanoparticles are observed.

Success from widening access to basic science research tools and synchrotron expertise in Africa

A focus of UNESCO’s International Year of Basic Sciences for Sustainable Development is ‘enhancing inclusive participation in science’. Diamond Light Source was a key partner in START, a collaborative project that sought to foster the development of Synchrotron Techniques for African Research and Technology (START), which ran from 2018 to 2021 with a £3.7 M grant from the Global Challenges Research Fund (GCRF) provided by the UK’s Science and Technology Facilities Council (STFC). Today on World Science Day for Peace and Development, we are highlighting health and energy research enabled by START.

Diamond played a pivotal role in the project, providing African scientists with crucial access to world class synchrotron techniques, beamtime, training and mentoring. Research focused on structural biology and energy materials to address key United Nations’ Sustainable Development Goals for health (SDG 3), energy (SDG 7), climate (SDG 13), and life-long learning (SDG 4).

Addressing worldwide energy challenges

Catalysis is essential for the development of a sustainable world and was a focus of the energy materials arm of the grant, along with solar energy, which is a well-recognised sustainable energy solution. These are just two areas in the physical sciences that were investigated as part of START.

Working towards better renewable energy solutions

Catalysis has many applications in renewable energy, where waste biomass is converted to liquid biofuels, or waste CO2 is converted to high value chemicals that can be used in our daily life, or as an alternative to fossil fuels. These applications rely on catalysts but to make this process more sustainable and efficient, advanced techniques are required to understand how the catalysts work under operating conditions. A group of START collaborators used Diamond to understand more about catalyst materials. They were investigating furfural, a bio-derived molecule that can be converted to many useful products that can be used for renewable energy. However, bio-derived compounds are highly functionalised – many parts of the molecular structure can undergo chemical change. Palladium (Pd) nanoparticles are widely used as an active component in furfural hydrogenation – a specific type of reaction that involves the addition of hydrogen to a compound – however, selectivity to specific products is a big challenge. Using X-ray absorption spectroscopy at Diamond, the team demonstrated that a Pd/NiO catalyst can hydrogenate furfural using a dual site process. This work has significant implications for the upgrading of bioderived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals.

Read more on the Diamond website

Image: START logo

Electrons and photons in a twin pack

Resonant two-photon ionisation of helium measured with angular resolution

Using a new experimental method, physicists from the Max Planck Institute for Nuclear Physics in Heidelberg investigated the resonant two-photon ionisation of helium with improved spectral resolution and angular resolution. For this purpose, they utilised a reaction microscope in combination with a high-resolution extreme-ultraviolet (EUV) photon spectrometer developed at the Institute. The measurements have been performed at the Free Electron Laser in Hamburg (FLASH), a brilliant radiation source, delivering intense EUV laser flashes. This allows the events from each individual laser flash to be analysed in terms of photon energy, yielding spectrally high-resolution data sets.

Helium, as the simplest and most accessible multi-electron system, is ideally suited for fundamental theoretical and experimental studies. Here, the mutual electrical repulsion of the two electrons plays an essential role – it accounts for a good third of the total binding energy. Of particular and fundamental interest is the interaction with photons (the quanta of light). Researchers from the groups around Christian Ott and Robert Moshammer in the division of Thomas Pfeifer at the Max Planck Institute for Nuclear Physics in Heidelberg have investigated the resonant two-photon ionisation of helium in detail at the free-electron laser FLASH of DESY in Hamburg.

Read more on the DESY website

Image: Fig. 2: Spectrum of photons unsorted (top) and sorted by peak position (bottom).

Artificial intelligence deciphers detector “clouds” to accelerate materials research

A machine learning algorithm automatically extracts information to speed up – and extend – the study of materials with X-ray pulse pairs.

X-rays can be used like a superfast, atomic-resolution camera, and if researchers shoot a pair of X-ray pulses just moments apart, they get atomic-resolution snapshots of a system at two points in time. Comparing these snapshots shows how a material fluctuates within a tiny fraction of a second, which could help scientists design future generations of super-fast computers, communications, and other technologies.

Resolving the information in these X-ray snapshots, however, is difficult and time intensive, so Joshua Turner, a lead scientist at the Department of Energy’s SLAC National Accelerator Center and Stanford University, and ten other researchers turned to artificial intelligence to automate the process. Their machine learning-aided method, published October 17 in Structural Dynamics, accelerates this X-ray probing technique, and extends it to previously inaccessible materials.

“The most exciting thing to me is that we can now access a different range of measurements, which we couldn’t before,” Turner said.

Handling the blob

When studying materials using this two-pulse technique, the X-rays scatter off a material and are usually detected one photon at a time. A detector measures these scattered photons, which are used to produce a speckle pattern – a blotchy image that represents the precise configuration of the sample at one instant in time. Researchers compare the speckle patterns from each pair of pulses to calculate fluctuations in the sample.

“However, every photon creates an explosion of electrical charge on the detector,” Turner said. “If there are too many photons, these charge clouds merge together to create an unrecognizable blob.” This cloud of noise means the researchers must collect tons of scattering data to yield a clear understanding of the speckle pattern.

“You need a lot of data to work out what’s happening in the system,” said Sathya Chitturi, a Ph.D. student at Stanford University who led this work. He is advised by Turner and coauthor Mike Dunne, director of the Linac Coherent Light Source (LCLS) X-ray laser at SLAC. 

Read more on the SLAC website

Image: A speckle pattern typical of the sort seen at LCLS’s detectors

Credit: Courtesy Joshua Turner

Towards improved osteoporosis treatment

More than 2.3 million Canadians are affected by osteoporosis, resulting in billions of dollars in economic burden and incalculable suffering.

A research team from the College of Medicine at the University of Saskatchewan has developed a new approach to imaging that detects changes in bone tissue far more quickly than bone densitometry scans, the method currently used in health care. While the study was done using a rabbit model, the results could lead to improved drug treatment in humans with osteoporosis.

Using the BMIT beamline of the Canadian Light Source at the University of Saskatchewan, Dr. David Cooper and colleagues were able to see the incredibly tiny pores inside cortical bone, the dense outer surface of bone that accounts for the majority of bone mass. These pores change over time, showing how bone tissue is continuously removed and replaced.

The researchers stimulated this bone turnover using parathyroid hormone, then tracked the changes in the pores of the cortical bone in as little as 14 days.

Read more on the CLS website

Image: Longitudinal erosion rate (LER) assessment based on synchrotron radiation (SR) micro-CT and micro-CT co-registered scans

Long COVID and pulmonary fibrosis better understood thanks to innovative techniques

An international team of researchers has revealed how scarring occurs in Long-COVID and pulmonary fibrosis using innovative blood biomarkers and X-ray technology. This study, published in The Lancet – eBioMedicine, contributes to the knowledge on the pathophysiology of severe COVID-19 and thus its treatment.

Long-COVID syndrome, or the origin of the long-term consequences of SARS-CoV-2 infection, is still not fully understood, more than two years after the onset of the pandemic. In particular, the long-term changes in lung tissue following severe COVID-19 disease pose significant limitations for many patients. Some of these patients continue to develop post-COVID pulmonary fibrosis, which is characterised by rapid scarring of the lung tissue.

Until now, the scientific community didn’t understand the underlying mechanisms of this scarring and of specific blood markers that can predict this process. Now, an international research team led by doctors and researchers at the Institute of Pathology at the RWTH Aachen University Hospital, the Hannover Medical School (MHH), HELIOS University Hospital in Wuppertal, and the University Medical Center Mainz, in collaboration with scientists at University College London (UCL) and the European Synchrotron (ESRF), has uncovered the mechanism that modifies the connective tissue of the lung in severe COVID-19. By combining the latest in imaging and molecular biology techniques this multidisciplinary team uncovered a mechanism by which the connective tissue of the lung is modified in severe COVID-19. They have demonstrated how COVID-19 changes the structure of the finest blood vessels in the lung and found molecular markers of this damage in the blood of patients that might ultimately help diagnose and treat the condition.

Read more on the ESRF website

Image: Two of the co-authors, Claire Walsh and Paul Tafforeau, during the scans and experiments at the ESRF, the European Synchrotron.

ForMAX beamline is now open for experiments

ForMAX, the newest beamline at MAX IV, is now officially open for experiments. The focus will be research on new, sustainable materials from the forest, but the beamline will also be useful for research in many other fields and industries, including food, textiles, and life science.

ForMAX is specially designed for advanced studies on wood-based materials. It allows in-situ multiscale structural characterization from nm to mm length scales by combining full-field tomographic imaging, small- and wide-angle X-ray scattering (SWAXS), and scanning SWAXS imaging – in a single instrument.

The beamline is an initiative where several market-leading industry companies, mainly from the paper and pulp industry, and academia have joined forces. The construction work has been funded by the Knut and Alice Wallenberg Foundation, and the operational costs are funded by the industry through Treesearch, a national collaborative platform for academic and industrial research in new materials from the forest.

One goal with ForMAX is to facilitate the development of new, wood-based products that can replace today’s plastic products.

Read more on the MAX IV website

Image: ForMAX beamline

Credit: Anna Sandahl, MAX IV

New orbit for electrons

Energy savings and a solution to a beam orbit correction problem are the results of a recent optimization carried out as part of a project initiated by Dr. Roman Panaś of the Accelerators Department. The correction problems stemmed from suboptimal alignment of the electron beam position “centers” (so-called offsets). It turned out that the correction magnets were undergoing periodic saturation, which made it impossible to maintain the correct orbit. Optimization of the beam orbit was essential, as it indirectly affects the quality and power of synchrotron light. It took about 2 months to develop and implement the new algorithms.

Precision at the synchrotron

Synchrotrons are a large, if not the largest, research infrastructure. Despite their size and diameters that range from tens to hundreds of meters, the precision of individual components is extremely important. As with a space rocket, accuracy to the hundredth of a millimeter on a synchrotron is crucial to the operation of the entire machine. This is why the synchrotron beam optimization project was such a great challenge. At the center of the initiative were the correction magnets, which directly affect the orbit of the electrons in the circular accelerator (ring). The orbit of electrons is determined by an algorithm and corrected in the vertical and horizontal axes with an accuracy that reaches fractions of micrometers.

The correction magnets got periodically saturated

The accumulation ring, in which the electrons circulate, is made up of 12 blocks of electromagnets. These blocks are called Double-Bend Achromat (DBA) cells. A typical DBA cell consists of two bending magnets, focusing magnets, and correction magnets. It is the latter that the team of researchers led by Dr. Roman Panaś, the originator of the project, focused on.

Steering magnets are responsible for keeping circulating electrons at the correct orbit. Until now, many power supplies for the correction magnets went to maximum currents, which is called saturation (reaching values of 11 A). This caused disturbances in the proper functioning of the beam correction. When electron beam is not properly corrected, it begins to oscillate in an uncontrolled manner, and resulting in faster electron beam losses.

Read more on the SOLARIS website