“Invisible ink” on antique Nile papyrus revealed by multiple methods

Researchers from the Egyptian Museum and Papyrus Collection, Berlin universities and Helmholtz-Zentrum Berlin studied a small piece of papyrus that was excavated on the island of Elephantine on the River Nile a little over 100 years ago.

The team used serval methods including non-destructive techniques at BESSY II. The researchers’ work, reported in the Journal of Cultural Heritage, blazes a trail for further analyses of the papyrus collection in Berlin.

The first thing that catches an archaeologist’s eye on the small piece of papyrus from Elephantine Island on the Nile is the apparently blank patch. Researchers from the Egyptian Museum, Berlin universities and Helmholtz-Zentrum Berlin have now used the synchrotron radiation from BESSY II to unveil its secret. This pushes the door wide open for analysing the giant Berlin papyrus collection and many more.

>Read more on the BESSY II at HZB website

Illustration: A team of researchers examined an ancient papyrus with a supposed empty spot. With the help of several methods, they discovered which signs once stood in this place and which ink was used.
Credit: © HZB

Brookhaven Lab and University of Delaware begin joint initiative

Through this partnership, scientists from both institutions will conduct collaborative research on rice soil chemistry and quantum materials.

The U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and the University of Delaware (UD) have begun a two-year joint initiative to promote collaborative research in new areas of complementary strength and strategic importance. Though Brookhaven Lab and UD already have a tradition of collaboration, especially in catalysis, this initiative encourages partnerships in strategic areas where that tradition does not yet exist. After considering several potential areas, a committee from Brookhaven and UD selected two projects—one on rice soil chemistry and the other on quantum materials—for the new initiative. For each project, one graduate student based at Brookhaven and one graduate student from UD will work with and be supervised by a principal investigator from each respective institution. The research, to start in October 2019, is funded separately by the two institutions. Brookhaven funding is provided through its Laboratory-Directed Research and Development program, which promotes highly innovative and exploratory research that supports the Lab’s mission and areas for growth.

>Read more on the NSLS-II at Brookhaven Lab website

Image: Principal investigators from Brookhaven Lab and the University of Delaware (UD) will collaborate on two different research projects through a new joint initiative. Brookhaven’s Peter Johnson (left) and UD’s Stephanie Law (second from left) will measure the energy level spectrum of a topological insulator, a new type of material that behaves as an insulator internally but as a conductor on the surface; Brookhaven’s Ryan Tappero (second from the right) and UD’s Angelia Seyfferth (right) will study how toxic and nutrient metals are distributed in rice grain.

A little bit of the moon just landed at ANSTO

Research on lunar meteorite and moon crater analogues coincides with Science Week.

Researchers at the Australian Synchrotron are currently collaborating on a particularly rare, other-worldly sample; a lunar meteorite. “Although we do work on the moons of the outer planets, I believe this is our first sample from Earth’s moon, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

Lunar meteorites are rocks found on Earth that were ejected from the Moon by the impact of an asteroid or another body. “These objects, which originate primarily from the moon’s crust, are extremely rare and precious. Because of their scarcity, scientists often use analogues or man-made versions of meteorites for investigations. “At the moment it is quite exciting as I have two projects relating to actual and analogue lunar objects, both of which are scheduled for the Imaging and Medical Beamline at the Synchrotron,” she said. n, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

>Read more on the Australian Synchrotron at ANSTO website

Preventing heart attacks

Scientists have taken an important step towards finding a potential cure for the disease that causes strokes and heart attacks in seniors and increases the mortality rate of diabetic and chronic kidney disease patients.
Researchers from the University of McGill and SickKids Toronto in collaboration with Universite de Montreal developed a simplified laboratory model that mimics the formation of mineral deposits that harden arteries and leads to these devastating conditions.
They used the Canadian Light Source (CLS) at the University of Saskatchewan to understand the type of minerals that formed and how they develop on the arteries.
“The goal in developing our lab model is that it would help us understand the mineralization process. We can then mimic what happens, and use it to test hypotheses on why the minerals are forming and also test some drugs to find something that can stop it,” said lead researcher Dr. Marta Cerruti.
Her six-member team is focused on the poorly understood process of how minerals form and grow on elastin, a protein on artery walls that provides the elasticity needed for blood flow to the heart, said Cerruti, an associate professor in Materials Engineering at McGill.
The hypothesis is that calcium phosphate-containing minerals form inside the walls of arteries and then calcify into a bone-like substance that narrows arteries and causes them to lose elasticity crucial for blood flow.

>Read more on the Canadian Light Source website

Image: Marta Cerruti (left) and Ophelie Gourgas in a laboratory using a Raman machine.

Using reed waste for sustainable batteries

With the changing climate, researchers are focusing on finding sustainable alternatives to conventional fuel cells and battery designs. Traditional catalysts used in vehicles contribute to increasing carbon dioxide emissions and mining for materials used in their design has a negative impact on the environment. Prof. Shuhui Sun, a researcher from the Institut National de la Recherche Scientifique (INRS) in Montreal, and his team used the Canadian Light Source (CLS) at the University of Saskatchewan to investigate an Iron-Nitrogen-Carbon catalyst using reed waste.

They hope to use the bio-based materials to create high-performance fuel cells and metal-air batteries, which could be used in electric cars. “An efficient oxygen electrocatalyst is extremely important for the development of high-performance electrochemical energy conversion and storage devices. Currently, the rare and expensive Pt-based catalysts are commonly used in these devices. Therefore, developing highly efficient and low-cost non-precious metal (e.g., Fe-based) catalysts to facilitate a sluggish cathodic oxygen reduction reaction (ORR) is a key issue for metal air batteries and fuel cells,” said Qilang Wei, the first author of the paper.

>Read more on the Canadian Light Source website

Advanced Photon Source upgrade

The U.S. Department of Energy (DOE) Office of Science (SC) has given DOE’s Argonne National Laboratory approval in the next phase of the $815M upgrade of the Advanced Photon Source (APS), a premier national research facility that equips scientists for discoveries that impact our technologies, economy, and national security.
DOE’s Critical Decision 3 (CD-3) milestone approval is a significant recognition of DOE’s acceptance of Argonne’s final design report for the complex APS Upgrade (APS-U), and authorizes the laboratory to proceed with procurements needed to build the nation’s brightest energy, storage-ring based X-ray source. The upgrade positions the APS to be a global leader among the new generation of storage-ring light sources that is now emerging.
Argonne’s APS, which works like a giant X-ray microscope, is a DOE Office of Science User Facility supported by the Scientific User Facilities Division of the Basic Energy Sciences Program in the Office of Science. It produces extremely bright, focused X-rays that peer through dense materials and illuminate the structure and chemistry of matter at the molecular and atomic level. By way of comparison, the X-rays produced at today’s APS are up to one billion times brighter than the X-rays produced in a typical dentist office.

Read more on the APS at Argonne National Laboratory website

Third user run successfully completed, fourth starting soon

Around 600 scientists visit the facility for experiments during user period.

The third user experiment period at European XFEL, which ran from November 2018, was successfully completed in June 2019. The X-ray beam was available for experiments for a total of 18 weeks. Twenty-eight user experiments were carried out at all six instruments, and 599 users were welcomed to the facility.

While only two instruments were operational at the beginning of the run, a further four started operation during the period, so that all six instruments were operational by the end of the run. Many other systems also had to first be prepared so that everything worked together. This included the accelerator and electron beam system, which could distribute the beam on demand to the different light sources. Other systems that were optimized to reach the goal of parallel operation of all three beamlines included the X-ray optics and diagnostic systems in the tunnels, elements at the instruments themselves that deal with the X-ray beam and specimen delivery, detectors, and software and data storage systems.

>Read more on the European XFEL website

Picture: The MID experiment station was one of the four to begin user operation during user run 3.
Credit: European XFEL / Jan Hosan

Research on shark vertebrae could improve bone disease treatment

The U.S. Department of Energy’s Advanced Photon Source (APS) at Argonne National Laboratory has facilitated tens of thousands of experiments across nearly every conceivable area of scientific research since it first saw light more than two decades ago.
But it wasn’t until earlier this year that the storied facility was used to study shark vertebrae in an experiment that one Northwestern University researcher hopes will shed light on the functionality of human bone and cartilage. Shark spines constantly flex when they swim, said Stuart R. Stock, a materials scientist and faculty member of Northwestern’s Feinberg School of Medicine. Yet they remain surprisingly resilient throughout the fish’s lifetime, he said.

Human bones, however, cannot endure the same kind of bending and become more fragile as people age. Stock is using the APS to better understand shark vertebrae’s formation and strength. He wants to know how the animal’s tissue develops and how it functions when the animal swims.

>Read more on the APS at Argonne National Laboratory website

Tuning material properties with laser light

The research results suggest the possibility of creating microelectronic devices that use a laser beam to erase and rewrite bits of information in materials engineered for random-access memory and data storage.

Many semiconductor-based devices use electric currents to control and manipulate bits of information encoded into tiny magnetic domains. However, this approach is reaching the physical limits of thermally stable feature sizes, and scientists are actively searching for the next generation of materials and processes that could lead to smaller, faster, more powerful devices.
One possible path forward has been opened up by the emergence of materials that can be engineered, layer by layer, to theoretical specifications. Multiferroics, for example, are designed materials with technologically useful properties that can be controlled by external fields. While many studies have been performed on the effects of electric and magnetic fields on multiferroics, very few studies have explored the use of optical modulation (i.e., laser light) as a way to tune magnetic and electronic ordering in such materials.

>Read more on the Advanced Light Source at LBL website

Images: They are taken at the same illuminated region using PFM, PEEM with linearly polarized x-rays, and PEEM with circularly polarized x-rays. The strong black and white contrast in the linear dichroism image indicates the antiferromagnetic order; the red/blue contrast in the circular dichroism image shows the existence of ferromagnetic moments that lie parallel/antiparallel to the incident x-rays, respectively.

New method to get stable perovskite-based material for more efficient solar cells

Perovskites materials are promising candidates for next generation solar cells. However, their use is still limited by their instability within ambient conditions. Instead of absorbing all visible light and appearing black, some of these super materials preferentially form another structure which is yellow. Since only the black form is optically active, the current challenge is achieving stable black perovskites thin films suitable for real world optoelectronic devices. An international team of scientists, led by a group from KU Leuven in Belgium, have shone a light on this problem developing a new method to stabilize the black form introducing strain into the perovskite thin film using the glass substrate on which it sits. Synchrotron-based techniques at the ALBA Synchrotron and the European Synchrotron Radiation Facility were crucial for obtaining these results, published today in Science.

>Read more on the ALBA website

Visualizing electrostatic gating effects in two-dimensional heterostructures

Electronic and optoelectronic devices utilise electric fields to manipulate material properties, controlling band structures and band alignments across heterostructures that combine metals, semiconductors and insulators. With two-dimensional materials, 2D heterostructures (2DHS) can be fabricated with atomic precision by simply stacking layers. In these, applied out-of-plane electric fields are a powerful tool that can be used to degenerately dope semiconductors, modify electronic structure through the Stark effect, and alter band-alignments between layers. As a result, out-of-plane electric fields have been used to engineer functional architectures such as high-efficiency light-emitting diodes and tunnelling transistors, and to probe many-body phenomena.
Despite the fundamental importance of electric-field control over band structure, direct experimental measurements are challenging and have been limited. Whilst gate electrodes are routinely applied for electrical transport investigations, and many studies have reported electric-field dependent light-emission from 2DHS, these depend upon but do not directly reveal the single-particle electronic structure. Angle resolved photoemission spectroscopy (ARPES) has proven to be a powerful tool for probing the momentum-resolved valence band structure of 2D materials such as graphene and semiconducting transition metal dichalcogenides (MX2). But it is challenging to apply conventional ARPES, which typically averages over lengthscales > 100 µm, to 2DHS which are usually only a few µm across. Using the high spatial resolution and flux of the Spectromicroscopy beamline at Elettra, we have shown that submicrometre spatially resolved ARPES (µARPES) can determine band parameters and band alignments across 2DHS of mechanically exfoliated flakes. These heterostructures are similar to those used for optical spectroscopy and transport measurements, opening the way to study operating devices.

>Read more on the Elettra website

Illustration: Direct momentum-resolved electronic structure measurements of in-operando microelectronic devices.

Research on how light-harvesting bacteria toggle off and on

The results could have long-range implications for artificial photosynthesis and optogenetics—the use of light to selectively activate biological processes.

Cyanobacteria are water-dwelling microbes capable of absorbing sunlight and converting it into chemical energy through photosynthesis. Long ago, ancient versions of these bacteria were incorporated into plant cells, where they eventually evolved into chloroplasts, the organelles responsible for carrying out photosynthesis in green plants. Today, in seeking to develop artificial photosynthesis to harness the sun’s abundant energy, scientists look to cyanobacteria to better understand the nuts and bolts of how natural photosynthesis works.

Cyanobacterial “off switch”

One topic of interest is how cyanobacteria respond to too much light. If a sunlight-harvesting system becomes overloaded with absorbed solar energy, it most likely will suffer some form of damage. Nature has solved the problem in cyanobacteria through a protective mechanism—an energy-quenching “off switch” in which excess solar energy is safely dissipated as heat.

>Read more on the Advanced Light Source at BNL

Illustration: X-ray footprinting provides time-resolved information about where key conformational changes occur. On the left is the overall OCP structure. The two structures on the right highlight local areas with increasing protein packing over time (blue shading) and areas with decreasing protein packing over time (red shading). The changes in accessibility are initiated by the movement of the carotenoid molecule (magenta chain).

Disorder raises the critical temperature of a cuprate superconductor

The origin of high-temperature superconductivity remains poorly understood to date. Over the past two decades, spatial oscillations of the electronic density known as charge-density waves (CDWs) have been found to coexist with high-temperature superconductivity in most prominent cuprate superconductors. The debate on whether CDWs help or hinder high-temperature superconductivity in cuprates is still ongoing. In principle, disorder at the atomic scale should strongly suppress both high-temperature superconductivity and CDWs. In this work, however, we find that disorder created by irradiation increases the superconducting critical temperature by 50% while suppressing the CDW order, showing that CDWs strongly hinder bulk superconductivity. We show that this increase occurs because the CDWs could be frustrating the superconducting coupling between atomic planes.

>Read more on the CHESS website

Image:  In an ideal system, orthogonal charge-spin stripes in adjacent layers prevent Josephson coupling between layers. Left: In the presence of disorder, distorted stripes around defects are not orthogonal, which reestablishes Josephson coupling between layers and increases TC.

A step closer to smart catalysts for fuel generation

Researchers at the Universidade Federal do Rio Grande do Sul in Brazil in collaboration with the ALBA Synchrotron have performed the first detailed measurement of the strong metal-support interaction (SMSI) effect in Cu-Ni nanoparticles supported on cerium oxide.

A better understanding of this effect is essential for developing smart catalysts that are more selective, stable and sustainable. The quest for the best catalysts in industry has been a long one, but a new study by Universidade Federal do Rio Grande do Sul in Brazil, in collaboration with the ALBA Synchrotron, has come a step closer. For the first time, researchers have found evidence of what could be the origin of the SMSI effect in catalysts supported on cerium oxide.

Catalysts are used to increase the reaction rate of a given chemical reaction, and have applications in a wide variety of fields. In heterogeneous catalysis, the catalyst is usually composed of metal nanoparticles supported on metal oxides. Among them, CeO2-based catalysts have unique structural and atomic properties that make them suitable in the cutting-edge environmental industry of fuel cells and hydrogen. In this field, they are being explored as high-end photocatalytic reactors for the thermal splitting of water and carbon dioxide. However, what has been termed as the SMSI effect can undermine their desired properties.

>Read more on the ALBA website

Image: (extract, full picture here) Near Ambient Pressure – X-ray Photoemission Spectroscopy allowed the identification of the chemical components of the nanoparticles in situ.

Mutated protein could become a non-hormonal contraceptive target

An international team of scientists from the Karolinska Institutet in Sweden and Nagoya University has explained how mutations in egg coat protein ZP1 cause infertility in women. The study suggests that ZP1 could be a promising candidate for future non-hormonal contraceptive efforts.
ZP1 is a glycoprotein involved in the fertilization of eggs by cross-linking egg coat filaments. Because studies in mice showed that lack of ZP1 reduces but does not abolish fertility, scientists believed that this molecule was also not crucial for fertility in humans. This new study, however, suggests that ZP1 may have a much more important role in human reproduction than previously thought. “The results were a big surprise because they suggested that mutations that truncate the human ZP1 protein cause female sterility by hindering its cross-linking function, rather than interfering with other egg coat proteins”, explains Luca Jovine, professor at the Karolinska Institutet and leader of the study.

>Read more on the ESRF website

Image: The mutation W83R of human ZP1 does not hinder its secretion but reduces its cross-linking (panel b), likely due to the fact that – as suggested by the structure of chicken ZP1 (panel a) – W83 (W72 in chicken ZP1) stacks between a sugar attached to ZP1 and the loop that makes the cross-link (“cd loop”). The part of the sugar chain that stacks against W83, which is a fucose residue, was only resolved in the structure of the fully glycosylated protein (violet) whose data came from ESRF ID23-1.

X-rays find key insights in metal-oxide thin film interfaces

Researchers from the Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) and ALBA Synchrotron have led a collaborative research, together with the Institut Català de Nanociència i Nanotecnologia (ICN2), the Dept. of Electronics and Biomedical Engineering (University of Barcelona) and CIC nanoGUNE (Donostia), where they have exploited X-ray absorption spectroscopy at the BOREAS beamline of ALBA for unveiling the optical and spin transport properties of transition metal oxides for photovoltaics and spintronics applications.
There is an urgent need of metallic and transparent electrodes for applications in advanced technologies such as flat panel displays or electrodes for photovoltaics, that may substitute the ubiquitous and exceedingly expensive and scarce Indium-Tin oxide (ITO). The AMO3 perovskites (being A an alkaline earth and M an early 3d transition metal, e.g. SrVO3) are driving attention because their intrinsic metallic character combines with the strong electron correlation within the narrow 3d band, to produce a material having its plasma frequency down to infrared and thus transparent at visible range.

>Read more on the ALBA website

Image: Illustration of different phenomena occurring at the interface between a ferromagnetic insulator and a heavy metal.