Microplastics limit energy production in tiny freshwater species

Paramecium bursaria
Image Credit: Picturepest
(CC BY 2.0)

Microplastic pollution reduces energy production in a microscopic creature found in freshwater worldwide, new research shows.

Paramecium bursaria contain algae that live inside their cells and provide energy by photosynthesis.

A new study, by the University of Exeter, tested whether severe microplastic contamination in the water affected this symbiotic relationship.  

The results showed a 50% decline in net photosynthesis – a major impact on the algae’s ability to produce energy and release oxygen.

“The relationship I examined – known as photosymbiosis – is commonly found both in freshwater and the oceans,” said Dr Ben Makin, lead author and associate researcher at the Environment and Sustainability Institute on Exeter’s Penryn Campus in Cornwall.

“We know climate change can damage photosymbiotic relationships, including in corals (leading to ‘bleaching’ events).

Mapping Migration

Avian research often focuses on forests as breeding habitats, but scientists are now working to understand the vital role that small forest patches play in migration. For the first time, a team of researchers from Princeton University and the University of Delaware has created a comprehensive map of migratory pathways and stopover locations in the Eastern United States.
Illustration Credit: Jeffrey C. Chase

Researchers release first comprehensive map of migratory bird patterns in Eastern U.S.

When the song pauses in a game of musical chairs, everyone jostles for one of the remaining seats. Bird migration today is much the same. When it’s time for a break in their biannual travels, songbirds descend to rest and refuel, searching for respite in a dwindling number of forest patches.

Avian research often focuses on forests as breeding habitats, but scientists are working to understand the role that small forest patches play in migration — a vital portion of a bird’s lifecycle when you consider that some species spend as much as half the year in transit. Now, for the first time, a team of researchers from Princeton University and the University of Delaware has created a comprehensive map of migratory pathways and stopover locations in the Eastern United States.

“Small pockets of deciduous forest are often neglected in conservation planning because birds have low breeding success in these spaces,” said Princeton University doctoral candidate Fengyi Guo, lead author of the study. “But the entire population moves across the continent twice annually. Many of them depend on food and shelter in these forest pockets to complete their migration and a chain is only as strong as its weakest link. Successful conservation of migratory bird populations requires enough habitat to be protected at all stages of its annual cycle.”

Researchers discover a way to fight the aging process and cancer development

Microscope image of C. elegans 10 days after treatment with UV-B rays. Left: Worms with intact DREAM complex cannot repair DNA well. Right: Worms without DREAM complex repair damage and live longer.
Image Credit: © Schumacher Lab

Damage in the human genome can be repaired. But this works better in germ cells, sperm and eggs, than in normal body cells. Responsible for this is the DREAM protein complex, which prevents the activation of all available repair mechanisms. A research team at the University of Cologne has now shown that normal body cells can also be repaired better once this complex has been deactivated. In the long run, the scientists hope to develop better therapies to prevent cancer and aging-associated diseases. 

A protein complex prevents the repair of genome damage in human cells, in mice and in the nematode Caenorhabditis elegans, a team of researchers at the University of Cologne has discovered. They also successfully inhibited this complex for the first time using a pharmaceutical agent.

“When we suppress the so-called DREAM complex in body cells, various repair mechanisms kick in, making these cells extremely resilient towards all kinds of DNA damage,” said Professor Dr Björn Schumacher, Director of the Institute for Genome Stability in Aging and Disease at the University of Cologne’s CECAD Cluster of Excellence in Aging Research.

Drought, Heat Waves Worsen West Coast Air Pollution Inequality

Shasta Lake, Calif. on August 25th, 2014 at Bridge Bay Resort and Marina. Lake Shasta is part of the Central Valley Project, operated by the U.S. Department of the Interior, Bureau of Reclamation.
Photo Credit: U.S. Department of the Interior, Bureau of Reclamation

A new study led by North Carolina State University researchers found drought and heat waves could make air pollution worse for communities that already have a high pollution burden in California, and deepen pollution inequalities along racial and ethnic lines.

Published in Nature Communications, the study also found financial penalties for power plants can significantly reduce people’s pollution exposure, except during severe heat waves.

“We have known that air pollution disproportionally impacts communities of color, the poor and communities that are already more likely to be impacted by other sources of environmental pollution,” said the study’s lead author Jordan Kern, assistant professor of forestry and environmental resources at NC State. “What we know now is that drought and heat waves make things worse.”

For the study, researchers estimated emissions of sulfur dioxide, nitrogen oxides and fine particulate matter from power plants in California across 500 different scenarios for what the weather could look like in future years, which they called “synthetic weather years.” These years simulated conditions that could occur based on historical wind, air, temperature and solar radiation values on the West Coast between 1953 and 2008. Then by using information about the location of power plants in California and how much electricity they would be generating under different weather conditions, they estimated air pollution within individual counties.

Tool developed to identify girls at risk of nutritional deficiency

Alexandra Pounds, Research Fellow at the University of Stirling's Institute of Aquaculture, in Bangladesh
Photo Credit: Courtesy of University of Stirling

A University of Stirling scientist has led a project which developed a new tool to identify girls in developing countries who are at risk of nutritional deficiency.

Professor Dave Little of the University’s world-renowned Institute of Aquaculture used the resource to discover that adolescent girls in Bangladesh are particularly vulnerable.

Aquaculture is a fast-growing food production sector in many low-income and food-deficit countries and whilst these ecosystems produce highly valuable and nutritious aquatic foods, local communities can still have a poor diet as a result of changes to the supply and accessibility of fish.

Professor Little said: “Adolescent girls represent a particularly vulnerable group in Bangladesh, with higher nutritional needs relative to energy requirements than other adult household members, and at the same time likely to have restricted access to food. 

“For this group, an optimal diet is critical for their own health and – in the case of early marriage and motherhood – for their infants.”

Wastewater could be the key to tracking more viruses than just COVID-19

Boehm lab graduate student Winnie Zambrana showing how wastewater samples are processed to test for evidence of viruses.
Photo Credit: Harry Gregory

Researchers have developed methods for using wastewater to track the levels of various respiratory viruses in a population. This can provide real-time information about virus circulation in a community.

Public health experts commonly track spikes in flu, respiratory syncytial virus (RSV), and rhinovirus circulating in a population through weekly reports from sentinel laboratories. These laboratories process samples from only severely ill patients, and it can take weeks for the results to get into the database. Now, for the first time, researchers at Stanford University, in collaboration with Emory University and Verily Life Sciences, have collected fast and accurate readings of a whole suite of respiratory viruses in their local Santa Clara sewer system.

Wastewater is currently the only source for accurate information about COVID-19 rates in communities. PCR testing is no longer widely available, and most people swab themselves at home where their results never reach public health agencies.

Prior to COVID-19, respiratory viruses had not been tracked through wastewater. Most of the viruses the scientists tested for in this study had never been measured in wastewater before. The findings are published in the March 22 issue of The Lancet Microbe.

Attack from the intestine

After an operation, bacteria can enter the organism from the intestine. Combat special cells of the immune system that are located in the liver.
Illustration Credit: Mercedes Gomez de Agüero

Darmbacteria are more common triggers of complications after surgery. This is shown by a new study by research teams from Würzburg and Bern. A solution to this problem could come from the liver.

German hospitals carried out almost 16 million operations in 2021. In Switzerland there are around 1.1 million. Even if the actual procedure is going well, it is not uncommon for a wound infection to occur afterwards, which can have dramatic consequences for those affected. In extreme cases, such infections are fatal.

A new study now shows that the causes of these infections are in a large part of the cases bacteria from the patient's intestine itself. To do this, the intestine does not even have to be injured during the operation. In this way, too, these pathogens overcome the intestinal barrier postoperatively and spread throughout the body through the blood and lymphatic pathways. They can be stopped by special immune cells that patrol all organs, including the liver.

Chemists Synthesize Material with Unusual Properties

Micrographs of ceramics based on barium stannate doped with yttrium. The percentage indicates the amount of yttrium in the tin sublattice. It can be used for electrolytes, electrodes and converters with varying amounts of additives
Photo Credit: Courtesy of the authors of the article

Researchers of the Institute of Hydrogen Energy of the Ural Federal University and the Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences have created a promising material for hydrogen energy devices. The new material has high proton conductivity and unusual properties (depending on the degree of doping). It can be used as an electrolyte (at high doping levels) and as an electrode (at low doping levels) in solid oxide fuel cells and electrolyzers. A description of the new material and the results of the study are presented in the Journal of Power Sources.

"We synthesized an electrolyte material with a perovskite structure based on barium stannate. By modifying barium stannate with different amounts of yttrium, we obtained materials with curious properties. At high degrees of substitution of tin for yttrium, the materials are ionic (protonic) conductors, which makes them promising electrolytes. At the same time, the introduction of a small amount of yttrium in the composition leads to a pronounced electron transport. This allows these materials to be used as electrodes for the same electrochemical devices, both solid oxide fuel cells (SOFC) and electrolyzers. This opens up wide possibilities for applications in electrochemical converters, in particular for oxygen-, hydrogen- and water-permeable membranes," explains Georgy Starostin, co-author and Research Engineer at the Hydrogen Energy Laboratory of UrFU.

At least 80% of the world’s most important sites for biodiversity on land currently contain human developments

Photo Credit: Siggy Nowak

A study has found that infrastructure worldwide is widespread in sites that have been identified as internationally important for biodiversity, and its prevalence is likely to increase.

This is the first ever assessment of the presence of infrastructure in Key Biodiversity Areas (KBAs): a global network of thousands of sites recognized internationally as being the world’s most critical areas for wildlife.

Infrastructure is one of the greatest drivers of threats to biodiversity according to the International Union for Conservation of Nature. It can cause natural habitat destruction and fragmentation, pollution, increased disturbance or hunting by humans, the spread of invasive species, direct mortality, and can have wider impacts beyond the development site.

Now, researchers from BirdLife International, WWF and the RSPB, in association with the University of Cambridge, have conducted an assessment of infrastructure in KBAs, finding that it is widespread and likely to increase. The results are published today in Biological Conservation.

“It’s concerning that human developments exist in the vast majority of sites that have been identified as being critical for nature,” said Ash Simkins, a Zoology PhD student at the University of Cambridge who led the study.

Pressure-Based Control Enables Tunable Singlet Fission Materials for Efficient Photoconversion

Applying hydrostatic pressure as an external stimulus, Tokyo Tech and Keio University researchers demonstrate a new way to regulate singlet fission (SF), a process in which two electrons are generated from a single photon, in chromophores, opening doors to the design of SF-based materials with enhanced (photo)energy conversion. Their method overrides the strict requirements that limit the molecular design of such materials by realizing an alternative control strategy.

Singlet fission (SF) is a process in which an organic chromophore (a molecule that absorbs light) in an excited singlet state transfers energy to a neighboring chromophore, resulting in two correlated triplet exciton pairs (pairs of bound electron-hole states, a "hole" signifying the absence of an electron) that decay to low energy triplet excitons. These excitons have long lifetimes and show efficient light emission, making SF promising for efficient light energy conversion.

However, the molecular design of SF-based materials is limited by the requirement that the energy of the excited singlet state must be at least equal to the energy of the two triplet states. One way to overcome this limit is by applying external stimuli, such as temperature or pressure, to manipulate the SF process.