Environmental toxin PCB found in deep sea trench

A sediment core has just been retrieved from the Atacama trench during an expedition with the research vessel R/V Sonne.
Photo Credit: Anni Glud / University of Southern Denmark

Despite being banned in numerous countries since the 1970s, PCBs continue to persist in the environment. Recent findings from deep-sea researchers reveal that PCBs have been detected at the depths of the Atacama Trench in the Pacific Ocean, highlighting the enduring impact of these toxic pollutants.

Throughout their deep-sea expedition, the research team retrieved sediment cores from multiple locations within the Atacama Trench and conducted meticulous analyses to detect PCB occurrences. Astonishingly, every single sample of surface sediment analyzed from all five locations within the trench was found to contain PCBs, indicating the widespread presence of these hazardous pollutants even in the remote depths of the ocean.

The groundbreaking study, helmed by Professor Anna Sobek from Stockholm University's Department of Environmental Science and Professor Ronnie N. Glud, esteemed director of the Danish Center for Hadal Research at the University of Southern Denmark, has been published in the prestigious scientific journal Nature Communications. This significant contribution sheds light on the alarming presence of PCBs in the Atacama Trench and underscores the urgent need for continued research and action to mitigate their adverse effects on marine ecosystems.

Leaps in artificial blood research aim to improve product safety, efficacy

Artificial blood has been used in a variety of clinical trials, but no safe alternative has yet made it to market.
Image Credit: Narupon Promvichai

Researchers have made huge strides in ensuring that red blood cell substitutes – or artificial blood – are able to work safely and effectively when transfused into the bloodstream.  

The key is to make the artificial blood molecules big enough so they don’t leak from blood vessels into tissue and cause dangerous cardiovascular side effects, notes a new study led by researchers from The Ohio State University. 

Although blood loss is typically treated by transfusing units of donated blood, in cases where transfusions aren’t readily available or time is too limited to screen for patient blood type compatibility (such as in certain rural areas or on the battlefield), artificial blood products offer medical professionals more flexibility for treatment. In clinical trials, previous generations of these blood substitutes often resulted in several poor health outcomes, as individuals experienced symptoms ranging from narrowing of blood vessels and high blood pressure to tissue injury.   

In this study, researchers found that a certain sized fraction of red blood cell substitute can provide a range of health benefits, and can decrease the risk of cardiovascular side effects – if its components are the right size. 

UC Irvine physicists discover first transformable nano-scale electronic devices

The golden parts of the device depicted in the above graphic are transformable, an ability that is “not realizable with the current materials used in industry,” says Ian Sequeira, a Ph.D. student who worked to develop the technology in the laboratory of Javiar Sanchez-Yamahgishi, UCI assistant professor of physics & astronomy.
Image Credit: Yuhui Yang / UCI

The nano-scale electronic parts in devices like smartphones are solid, static objects that once designed and built cannot transform into anything else. But University of California, Irvine physicists have reported the discovery of nano-scale devices that can transform into many different shapes and sizes even though they exist in solid states.

It’s a finding that could fundamentally change the nature of electronic devices, as well as the way scientists research atomic-scale quantum materials. The study is published this week in Science Advances.

“What we discovered is that for a particular set of materials, you can make nano-scale electronic devices that aren’t stuck together,” said Javier Sanchez-Yamagishi, an assistant professor of physics & astronomy whose lab performed the new research. “The parts can move, and so that allows us to modify the size and shape of a device after it’s been made.”

New approach estimates long-term coastal cliff loss

Jane Willenbring sampling shore platform bedrock in Del Mar with a hammer and chisel.
Photo Credit: Travis Clow

A new method for estimating cliff loss over thousands of years in Del Mar, California, may help reveal some of the long-term drivers of coastal cliff loss in the state.

In parts of California’s iconic mountainous coasts, breathtaking beauty is punctuated by brusque signs warning spectators to stay back from unstable cliffs. The dangers of coastal erosion are an all-too-familiar reality for the modern residents of these communities. Now, with a new tool, researchers are bringing historical perspective to the hotly debated topic of how to manage these disappearing coastlines.

Using a model that incorporates measurements of the amount of time coastal cliffs and their remnant deposits were exposed at the Earth’s surface, Stanford researchers found that the rate of cliff erosion in the past 100 years is similar to that of the past 2,000 years. The proof-of-concept, published in the Journal of Geophysical Research: Earth Surface April 17, opens the possibility of using this new approach to understand the long-term history of coastal cliff erosion, or retreat, in other parts of the state. The work was conducted in Del Mar, California, a beach town in San Diego County with infrastructure atop its coastal bluffs.

New genetic target for male contraception identified

Photo Credit: Filipe Almeida

Discovery of a gene in multiple mammalian species could pave the way for a highly effective, reversible and non-hormonal male contraceptive for humans and animals.

Washington State University researchers identified expression of the gene, Arrdc5, in the testicular tissue of mice, pigs, cattle and humans. When they knocked out the gene in mice, it created infertility only in the males, impacting their sperm count, movement and shape. The researchers detailed their findings in the journal Nature Communications.

“The study identifies this gene for the first time as being expressed only in testicular tissue, nowhere else in the body, and it’s expressed by multiple mammalian species,” said Jon Oatley, senior author and professor in WSU’s School of Molecular Biosciences. “When this gene is inactivated or inhibited in males, they make sperm that cannot fertilize an egg, and that’s a prime target for male contraceptive development.”

While other molecular targets have been identified for potential male contraceptive development, the Arrdc5 gene is specific to the male testes and found in multiple species. Importantly, lack of the gene also causes significant infertility creating a condition called oligoasthenoteratospermia or OAT. This condition, the most common diagnosis for human male infertility, shows a decrease in the amount of sperm produced, slowed mobility and distorted shape so that the sperm are unable to fuse with an egg.

Protein domain common to plants and animals plays role in COVID-19 infection

ORNL scientists mutated amino acids in a receptor protein, shown in green, which diminished interaction with the SARS-CoV-2 virus spike protein, shown in red. Mutating the receptor protein hampered the virus’s ability to infect host cells.
Image Credit: ORNL, U.S. Dept. of Energy

Oak Ridge National Laboratory scientists exploring bioenergy plant genetics have made a surprising discovery: a protein domain that could lead to new COVID-19 treatments.

Researchers found the same plasminogen-apple-nematode, or PAN, domain studied by ORNL in plants like poplar and willow is also present in the human NRP1 receptor protein. NRP1 is less studied than the ACE-2 receptor targeted by current COVID-19 treatments, but this research shows its promise as a future therapeutic target.

By mutating amino acids called cysteine residues in the PAN domain of NRP1, researchers disrupted the ability of the SARS-CoV-2 virus to use its spike protein to invade cells, as described in iScience. ORNL scientists have also linked PAN to the growth of cancerous tumors.

Testing coatings to conserve canisters against corrosion

Video Credit: Ruth Frank

As anyone who has lived near the ocean can attest, metal and sea mist are a recipe for corrosion. A nuisance of coastal life, the consequences of these common chemical reactions become far more serious when it is taking aim at the stainless-steel canisters that contain spent nuclear fuel.

To shield steel from the corrosive threats posed by sea air, Sandia National Laboratories researchers tested a variety of nickel mixtures as protective coatings on stainless steel. The researchers found that the specific material applied, and the specific application process used, impacted the properties of the coating, including how protective it was against corrosion. Their results were published recently in the scientific journal Frontiers in Metals and Alloys.

Spent nuclear fuel is stored in quite a few coastal areas, where sea breezes can buffet canisters and deposit corrosive chloride salts such as sodium chloride, or more commonly known as table salt. Given enough time, the brine formed by these salts can corrode and pit stainless-steel canisters.

“Through our research, it became clear that it would not be easy to completely eliminate the possibility of a type of corrosion known as stress corrosion cracking,” said Charles Bryan, an expert on the storage of spent nuclear fuel and co-lead on the project. “Stress corrosion cracking is likely to eventually occur at some interim storage sites. It might take hundreds of years, but it could happen, so people started thinking about mitigation and repair technologies. We started looking at cold spray, which is a technique industry is very interested in, and at corrosion-resistant polymer coatings.”

A neuromorphic visual sensor can recognize moving objects and predict their path

Conventional sensors only capture a single moment in a frame, but the new sensor can read information about the past and use that to predict the future.
Illustration Credit: Hongwei Tan / Aalto University

A new bio-inspired sensor can recognize moving objects in a single frame from a video and successfully predict where they will move to. This smart sensor, described in a Nature Communications paper, will be a valuable tool in a range of fields, including dynamic vision sensing, automatic inspection, industrial process control, robotic guidance, and autonomous driving technology. 

Current motion detection systems need many components and complex algorithms doing frame-by-frame analyses, which makes them inefficient and energy-intensive. Inspired by the human visual system, researchers at Aalto University have developed a new neuromorphic vision technology that integrates sensing, memory, and processing in a single device that can detect motion and predict trajectories. 

Female butterflies breed despite male shortage

Monarch Butterfly
Photo Credit: Erin Minuskin

Female monarch butterflies have no trouble finding a mate – even when a parasite kills most of the males, new research shows.

Some females carry a parasite called Spiroplasma that kills all their male offspring, meaning highly infected populations have very few males.

But the new study – by the universities of Exeter, Rwanda and Edinburgh, and the Dian Fossey Gorilla Fund – found females mated about 1.5 times on average, regardless of how many males were around.

The male proportion dropped below 10% in some cases, but it appears the remaining hard-working males managed to breed with most of the available females.

10-20% of females remained unmated, only slightly higher than the expected average in a population with plenty of males (5-10%).

Natural flood prevention, higher trust through better communication

2013 flood on the Elbe near Dessau-Rosslau.
Photo Credit: André Künzelmann / UFZ

A UFZ study shows: If the population feels well informed, it has a more positive view towards nature-based flood prevention

In many places today, dikes are being moved back, and floodplains are being revitalized in order to give the river more space during times of flooding. This should make flood protection more effective and reduce the risk of flooding in inhabited areas. Nevertheless, natural flood prevention projects are often met with considerable resistance from the general population. Why is that? Researchers from the Helmholtz Centre for Environmental Research (UFZ) and the University of Potsdam have investigated this question in a social science study. They found that fear, personal experience of flooding, and a lack of information play a particular role in this. According to the research team, when flood protection measures are planned, the general population should be involved and informed as early as possible. The study was recently published in Risk Analysis.

There have been repeated flood disasters in Germany in recent decades. For example, in 2002 and 2013 along the Elbe and in 2021 in the Eifel region. As climate change progresses, severe floods are expected to occur more frequently. It is therefore important to quickly implement effective protection measures in vulnerable areas.