Molecular cage protects precious metals in catalytic converters

Stable catalyst illustration
Source/Credit: Slac National Accelerator Laboratory

Sometimes, solutions to environmental problems can have environmentally unfriendly side effects. For example, while most gas-powered cars have a catalytic converter that transforms engine emission pollutants into less harmful gases, this comes with a tradeoff: Catalytic converters contain precious metals such as platinum and palladium.

The good thing about these precious metals is that they act as catalysts that help break down pollutants, with a suite of properties that make them the best elemental candidates for this chemical job. But they are also rare, which makes them expensive, and extracting them from the earth produces its own pollution.

However, in a paper published October 24 in Nature Materials, researchers at the SUNCAT Center for Interface Science and Catalysis and the Precourt Institute for Energy at Stanford University and the Department of Energy’s SLAC National Accelerator Laboratory reported a way of encapsulating catalysts that could reduce the number of precious metals catalytic converters need to work, which could in turn reduce the practice of precious metal mining.

“I think the material we made could knock down the number of precious metals used in a catalytic converter by 50 precent, which would mean a lot once you multiply that by the nearly 1.5 billion cars we now have in circulation on the planet,” said Matteo Cargnello, the new study's senior author and an assistant professor of chemical engineering at Stanford University.

Gestational Exposure to Flame Retardant Alters Brain Development in Rats

A new study from North Carolina State University shows that exposure in utero to the flame retardant FireMaster® 550 (FM 550), or to its individual brominated (BFR) or organophosphate ester (OPFR) components, resulted in altered brain development in newborn rats. The effects – most notably evidence of mitochondrial disruption and dysregulated choline and triglyceride levels in brain tissue – were greater in male offspring than in females. The work adds to the body of evidence that both OPFRs and BFRs can be neurotoxic.

FM 550 is a flame-retardant mixture first identified a decade ago. It was developed to replace PBDEs, a class of fire retardants being phased out due to safety concerns.

“While some new flame-retardant mixtures still contain BFRs, the OPFRs are a popular substitute for PBDEs, since it is believed that OPFRs don’t accumulate in the body and thus cannot be as harmful,” says Heather Patisaul, associate dean for research in NC State’s College of Sciences and corresponding author of the study. “Specifically, it was thought that OPFRs wouldn’t impact acetylcholinesterase – a key neurotransmitter. But it looks as though OPFRs still impact choline signaling and are just as bad if not worse than PBDEs for the developing brain.”

Patisaul and her colleagues performed transcriptomic and lipidomic studies on the prefrontal cortexes of newborn rats whose mothers had been exposed to FM550, or to BFR or OPFR elements individually, during gestation.

High-tech sensors could guide vehicles without satellites, if they can handle the ride

Sandia National Laboratories atomic physicist Jongmin Lee examines the sensor head of a cold-atom interferometer that could help vehicles stay on course where GPS is unavailable.
Photo credit: Bret Latter

Words like “tough” or “rugged” are rarely associated with a quantum inertial sensor. The remarkable scientific instrument can measure motion a thousand times more accurately than the devices that help navigate today’s missiles, aircraft and drones. But its delicate, table-sized array of components that includes a complex laser and vacuum system has largely kept the technology grounded and confined to the controlled settings of a lab.

Jongmin Lee wants to change that.

The atomic physicist is part of a team at Sandia National Laboratories that envisions quantum inertial sensors as revolutionary, onboard navigational aids. If the team can reengineer the sensor into a compact, rugged device, the technology could safely guide vehicles where GPS signals are jammed or lost.

In a major milestone toward realizing their vision, the team has successfully built a cold-atom interferometer, a core component of quantum sensors, designed to be much smaller and tougher than typical lab setups. The team describes their prototype in the academic journal Nature Communications, showing how to integrate several normally separated components into a single monolithic structure. In doing so, they reduced the key components of a system that existed on a large optical table down to a sturdy package roughly the size of a shoebox.

Microscopy reveals how psychedelics light up brain’s neuropathways

 Alex Kwan, Ph.D. ‘09, associate professor in the Meinig School of Biomedical Engineering, is using optical microscopy and other tools to map the brain’s neural response to psychedelic drugs, an approach that could lead to the development of fast-acting antidepressants
Photo credit: Ryan Young/Cornell University.

What a long, strange trip it’s been for psychedelic drugs. From their use in ancient indigenous ceremonies, to their often-caricatured association with the 1960s counterculture, to their recent reemergence as a potential therapeutic, hallucinogens have been embraced by very different communities for very different reasons. But scientists have never fully understood how these drugs actually work on the brain.

Alex Kwan, Ph.D. ‘09, associate professor in the Meinig School of Biomedical Engineering in the College of Engineering, is using optical microscopy and other tools to map the brain’s neural response to these psychoactive chemicals, an approach that could eventually lead to the development of fast-acting antidepressants and treatments for substance-use disorders and cluster headaches.

“We know more about the pharmacology, how psychedelics work at the structural level, interacting with the brain receptors. But there has been a big void in terms of understanding what they do to the brain itself, at the neural circuit level,” Kwan said. “There’s a chain of events that happen that ultimately lead to acute and longer-lasting behavioral changes that might be useful for treatment. But in between a lot of that is a black box.”

Despite the renewed interest in the benefits of psychedelics from popular figures such as environmentalist and author Michael Pollan, much of the research into these drugs was conducted in the 1950s and 60s with fairly rudimentary methods, Kwan said.

Penguin feathers may be secret to effective anti-icing technology

Gentoo penguins
Photo Credit: 66 north

Ice buildup on powerlines and electric towers brought the northern US and southern Canada to a standstill during the Great Ice Storm of 1998, leaving many in the cold and dark for days and even weeks. Whether it is on wind turbines, electric towers, drones, or airplane wings, dealing with ice buildup typically depends on techniques that are time consuming, costly and/or use a lot of energy, along with various chemicals. But, by looking to nature, McGill researchers believe that they have found a promising new way of dealing with the problem. Their inspiration came from the wings of Gentoo penguins who swim in the ice-cold waters of the south polar region, with pelts that remain ice-free even when the outer surface temperature is well below freezing.

We initially explored the qualities of the lotus leaf, which is very good at shedding water but proved less effective at shedding ice,” said Anne Kietzig, who has been looking for a solution for close to a decade. She is an associate professor in Chemical Engineering at McGill and the director of the Biomimetic Surface Engineering Laboratory. “It was only when we started investigating the qualities of penguin feathers that we discovered a material found in nature that was able to shed both water and ice.”

Sand serves up a possible cure for obesity

Engineered particles of purified sand could be the next anti-obesity therapy as new research from the University of South Australia published in journal MPDI Pharmaceutics shows that porous silica can prevent fats and carbohydrates from being adsorbed in the body.

The engineered silica particles are made from purified sand and are optimally designed with a high surface area that enables them to soak up large amounts of digestive enzymes, fats, and sugars within the gastrointestinal tract.

Funded by the Channel 7 Children’s Research Foundation, the study is the first to validate how porous silica particles can impede digestive processes and stop fat and sugar adsorption.

Developed in partnership with Glantreo Limited, the new silica-based therapy will be gentler on the stomach with fewer of the unpleasant side effects associated with the mainstream anti-obesity drug, Orlistat.

Lead researcher, UniSA’s Dr Paul Joyce says this breakthrough finding could change the health outcomes for billions of people struggling with obesity.

More yield, fewer species: How human nutrient intakes alter grasslands

Credit: Pete Linforth

High nutrient inputs in grassland lead to more plant species being lost than new ones can establish over longer periods of time. In addition, fewer new species settle than under natural nutrient availability. A worldwide experiment led by the German Centre for Integrative Biodiversity Research (iDiv), the Helmholtz Centre for Environmental Research (UFZ) and the Martin Luther University Halle-Wittenberg (MLU) has now been able to show why additional nutrient inputs reduce plant diversity in grasslands. The study published in "Ecology Letters", also sheds light on another issue: The increase in biomass with nutrient inputs is due to a few plant species that can use higher nutrient inputs to their advantage and remain successfully at a site over long periods of time.

One of the reasons for the global threat to biodiversity is that we humans introduce more nutrients into our environment than would naturally be present there, for example, when fertilizing agricultural land. In addition, precipitation re-distributes excess nutrients to other areas, and nutrients can also enter our soil through air pollution.

Natural grasslands are a habitat for many different plant species including grasses, herbs, wildflowers and orchids, many of which can be threatened by human activities and impacts. Plants need three things to grow: carbon dioxide (CO2) from the air, water and nutrients from the soil. The latter are usually scarce in semi-natural European meadows. Although this limits the growth of individual plants, it Favours the possibility of many different species growing side by side. Excessive amounts of nutrients, however, create the image that is ubiquitous in our landscape today: lush green meadows but without the colorful flowers of former times.

Mild thyroid disorders can cause serious heart problems

Johannes W. Dietrich works in the section diabetology, endocrinology and metabolism of Medical Clinic I in the RUB Clinic St. Josef Hospital.
Credit: Curtesy of Johannes W. Dietrich

A systematic evaluation of 32 studies with 1.3 million participants reveals new relationships.

It has been known for more than 200 years that severe over functions of the thyroid gland can lead to disturbances in the heart rhythm and thus to sudden cardiac death. So far, it has been unclear what risk is associated with only slight over- or under-functions. A systematic evaluation of 32 studies with 1.3 million participants shows that even slight deviations in thyroid function can increase the risk of serious cardiovascular diseases. "This puts our understanding of the interaction between the thyroid and the heart on a new footing and shows the way to personalized prevention," said private lecturer Dr. Johannes Dietrich from the medical clinic in St. Josef Hospital, Clinic of the Ruhr University Bochum (RUB). The researchers worked in the journal Frontiers in Cardiovascular Medicine.

For the work, the cardiac and hormone researchers of the RUB cooperated with the Tan Tock Seng Hospital, the Lee Kong Chian School of Medicine and the Duke-NUS Medical School in Singapore.

Scientists Created a Material Promising for Improving Brightness of Screens

One of the assembled organic LEDs based on push-pull systems.
Photo credit: Ruslan Gadirov / TSU

Scientists at the Postovsky Institute of Organic Synthesis, Ural Branch of the Russian Academy of Sciences, and Ural Federal University have developed, synthesized, and studied a series of new fluorophores - push-pull systems (compounds with pronounced electron-donor and electron-acceptor parts) based on cyanopyrazine. Ural chemists in cooperation with colleagues from Tomsk State University showed that the presence of a cyano group in the substance significantly increases the efficiency of organic light emitting diodes (OLEDs) based on it. This opens the prospect of creating new materials to enhance the brightness of displays of smartphones, computers and televisions. An article describing the research and its results was published in the journal Dyes and Pigments.

In previous research work, chemists demonstrated that one of the most promising compounds as an acceptor (attracting electrons) part in push-pull systems is the pyrazine ring (another name is 1,4-diazine), a compound of nitrogen, hydrogen and carbon that has a significant electron-accepting effect.

A revolutionary method to observe cell transport

Nanobodies (grey) with magnetic probes (red stars) target the desired membrane protein.
Credit: Bordignon, Enrica

Membrane proteins are key targets for many drugs. They are located between the outside and inside of our cells. Some of them, called ‘‘transporters’’, move certain substances in and out of the cellular environment. Yet, extracting and storing them for observation is particularly complex. A team from the University of Geneva (UNIGE), in collaboration with the University of Zurich (UZH), has developed an innovative method to study their structure in their native environment: the cell. The technique is based on electron spin resonance spectroscopy. These results, just published in the journal Science Advances, may facilitate future development of new drugs.

In living organisms, each cell is surrounded by a cell membrane (or ‘‘cytoplasmic membrane’’). This membrane consists of a double layer of lipids. It separates the contents of the cell from its direct environment and regulates the substances that can enter or leave the cell. The proteins attached to this membrane are called ‘‘membrane proteins’’.

Located at the interface between the outside and inside of the cell, they carry various substances across the membrane - into or out of the cell - and play a crucial role in cell signaling, i.e. in the communication system of cells that allows them to coordinate their metabolic processes, development and organization. As a result, membrane proteins represent more than 60% of current drug targets.