Garnet gemstones contain secrets of our seismic past

Somewhere in the world an earthquake is occurring. In general, it will be a small tremor, an earthquake of magnitude two or lower, which humans cannot even feel. However when a major earthquake occurs, of magnitude 7 or above, it can cause devastating damage, events like tsunamis, and loss of life. These type of quakes, like the 2011 event in Japan and 2015 Nepalese events, happen around 20 times each year worldwide.

Large earthquakes tend to occur in subduction zones, such as the so-called Ring of Fire, where tectonic plates meet and one is bent and forced underneath the other, into the mantle of the earth. As well as leading to earthquakes, subduction also causes the composition and structure of the rock itself to become altered, in a process called high-pressure/low temperature metamorphism.

Metamorphism can take a variety of forms, in a number of different rocks, but one that is of particular interest is a type called rhythmic major-element zoning, in the mineral garnet. If found it can be a sign that subduction has occurred, and it can act as a record of seismicity in the crust of our Earth.

>Read more on the Diamond Light Source website

Support for HZB’s future and call for rapid planning of Bessy III

The Helmholtz-Zentrum Berlin (HZB) has received an evaluation of “excellent” in a review of science programmes undertaken at all Helmholtz Research Centres.

This provides the foundation for future financing of HZB.
Two committees of leading international scientists visited the HZB for a week each at the beginning of this year. They evaluated the HZB’s contributions to the Helmholtz programmes in the research areas of “Matter” and “Energy”. Now the written evaluations are available. The team spirit of all employees involved in the HZB was particularly emphasised.

The report states that the HZB and the Helmholtz Association have made decisions characterised by vision. The right course had been set both in terms of infrastructure and in recruiting people. The HZB can rely on highly competent, committed employees at all levels.

All research programmes of the HZB have received an evaluation of “excellent”. The HZB contributions to the MML programme (From Matter to Materials and Life) focussing on the use of photons are considered to be leading, with all of its participating groups receiving the top marks of “Outstanding” or “Excellent”. The Renewable Energies (RE) and the Future Information Technologies (FIT) programmes, the instrumentation at the BESSY II synchrotron (some of which is unique), and the BER II research reactor were likewise evaluated highly.

>Read more on the Bessy II at HZB website

Image: The review panel of the research field “Matter” visited the HZB on 11th January 2018.
Credit: HZB/J. Bierbaum

 

 

Writing and deleting magnets with lasers

Scientists * have found a way to write and delete magnets in an alloy using a laser beam – a surprising effect.

* at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia in Charlottesville, USA

The reversibility of the process opens up new possibilities in the fields of material processing, optical technology, and data storage.
Researchers of the HZDR, an independent German research laboratory, studied an alloy of iron and aluminum. It is interesting as a prototype material because subtle changes to its atomic arrangement can completely transform its magnetic behavior. “The alloy possesses a highly ordered structure, with layers of iron atoms that are separated by aluminum atomic layers. When a laser beam destroys this order, the iron atoms are brought closer together and begin to behave like magnets,” says HZDR physicist Rantej Bali.

Bali and his team prepared a thin film of the alloy on top of transparent magnesia through which a laser beam was shone on the film. When they, together with researchers of the HZB, directed a well-focused laser beam with a pulse of 100 femtoseconds (a femtosecond is a millionth of a billionth of a second) at the alloy, a ferromagnetic area was formed. Shooting laser pulses at the same area again – this time at reduced laser intensity – was then used to delete the magnet.

>Read more on the Bessy II at HZB website

Image: Laser light for writing and erasing information – a strong laser pulse disrupts the arrangement of atoms in an alloy and creates magnetic structures (left). A second, weaker, laser pulse allows the atoms to return to their original lattice sites (right). (Find the entire image here)
Credit: Sander Münster / HZDR

Insights into the development of more effective anti-tumour drug

Natural killer cells are powerful weapons our body’s immune systems count on to fight infection and combat diseases like cancer, multiple sclerosis, and lupus. Finding ways to spark these potent cells into action could lead to more effective cancer treatments and vaccines.

While several chemical compounds have shown promise stimulating a type of natural killer cells, invariant natural killer T cells (iNKT) cells in animal models, their ability to activate human iNKT cells has been limited.

Now, an international team of top immunologists, structural biologists, and chemists published in Cell Chemical Biology the creation of a new compound that appears to have the properties researchers have been looking for. The research was co-led by Monash Biomedicine Discovery Institute’s (BDI) Dr Jérôme Le Nours, University of Connecticut’s Professor Amy Howell and Albert Einstein College of Medicine’s Dr Steve Porcelli. Dr Le Nours used the Micro Crystallography beamline (MX2) at the Australian Synchrotron as part of the study.

The compound – a modified version of an earlier synthesized ligand – is highly effective in activating human iNKT cells. It is also selective – encouraging iNKT cells to release a specific set of proteins known as Th1 cytokines, which stimulate anti-tumour immunity.

>Read more on the Australian Synchrotron website

Image: 3D structure of proteins behind interaction of new drug that stimulates immune response to cancer cells. (Entire image here)

Toward control of spin states for molecular electronics

Tungsten accumulation in bone raises health concerns

McGill University scientists have identified exposure to tungsten as problematic after they determined how and where high levels of the metal accumulate and remain in bone.

“Our research provides further evidence against the long-standing perception that tungsten is inert and non-toxic,” said Cassidy VanderSchee, a PhD student and a member of a McGill research group headed by chemistry professor Scott Bohle.

Tungsten is a hard metal with a high melting point and, when combined with other metals and used as an alloy, it’s also very flexible.

Because of these properties and under the assumption that tungsten is non-toxic, it has been tested for use in medical implants, including arterial stents and hip replacements, in radiation shields to protect tissue during radiation therapy, and in some drugs. Tungsten is found in ammunition as well as in tools used for machining and cutting other metals.

Tungsten also occurs naturally in groundwater where deposits of the mineral are found. Exposure to high levels of tungsten in drinking water in Fallon, Nevada, was investigated for a possible link with childhood leukemia in the early 2000s. This investigation lead scientists to question the long-held belief that exposure to tungsten is safe and prompted the Centers for Disease Control and Prevention in the U.S. to nominate tungsten for toxicology and carcinogenesis studies.

>Read more on the Canadian Light Source website

Image: Cassidy VenderSchee

Solution to plastic pollution on the horizon

Engineering a unique plastic-degrading enzyme

The inner workings of a recently discovered bacterium with a fascinating ability to use plastic as an energy source have been recently revealed in PNAS. The world’s unique Long-Wavelength Macromolecular Crystallography (MX) beamline here at Diamond Light Source was used to successfully solve the structure of the bacterial enzyme responsible for chopping up the plastic. This newly evolved enzyme could be the key to tackling the worldwide problem of plastic waste.

Plastic pollution is a global threat that desperately needs addressing. Plastics are rarely biodegradable and they can remain in the environment for centuries. One of the most abundant plastics that contributes hugely to this dire situation is poly(ethylene terephthalate) (PET).

PET is used largely in textiles, where it is commonly referred to as polyester, but it is also used as packaging for liquids and foodstuffs. In fact, PET’s excellent water-repellent properties led to it being the plastic of choice for soft drink bottles. However, once plastic bottles are discarded in the environment the water resistance of PET means that they are highly resistant to natural biodegradation. PET bottles can linger for hundreds of years and plastic waste like this will accumulate over time unless a solution is found to degrade them.

A recent breakthrough came in the discovery of a unique bacterium, Ideonella sakaiensis 201-F6, which was found feeding on waste from an industrial PET recycling facility. PET has only been widely used since the 1970s, so the bacterium had evolved at breakneck speed to be able to take advantage of the new food source.

The bacterium had the amazing ability to degrade PET and use it to provide carbon for energy. Central to this ability was the production of a PET-digesting enzyme, known as PETase.

>Read more on the Diamond Light Source website

 

W7 SSRL Slider

The Stanford Synchrotron Radiation Lightsource (SSRL) is one of the pioneering synchrotron facilities in the world, known for outstanding user support, training future generations and important contributions to science and instrumentation. SSRL is an Office of Science User Facility operated for the U.S. Department of Energy by Stanford University.

W12 FERMI Slider

The program of construction and commissioning through user experiments of the FEL source FERMI, the only FEL user facility in the world currently exploiting external seeding to offer intensity, wavelength and line width stability, achieved all of its intended targets in 2017.

W12 NSRRC Slider

Taiwan Light Source (TLS, 1.5 GeV) and Taiwan Photon Source (TPS, 3.0 GeV) are the two synchrotron light sources currently operated by the National Synchrotron Radiation Research Center (NSRRC). There are around 13,000 academic user visits to NSRRC every year; approximately 10% are international.