Unravelling how climate, pollution and runoff combine in coastal ecosystems

Source: Griffith University

Griffith University researchers are unravelling how stressors like climate change, pollution, dissolved nitrogen and sediment from run-off are having combined effects in coastal ecosystems.

Two studies published in Ecology Letters and Proceedings of the Royal Society B reveal combining increasing ocean temperatures, pollution or dissolved nitrogen with the reduced light caused by sediment in the water can either amplify or reduce the impact of these stressors individually on seagrass or algal growth.

Dr Mischa Turschwell, Research Fellow
at the Australian Rivers Institute

“Crucially, we show that the combined effects on seagrass and algal growth can vary significantly dependent on the amount of the two stressors and duration of exposure,” said Dr Mischa Turschwell, Research Fellow at the Australian Rivers Institute.

“With the onset of climate change, coastal and marine ecosystems are under threat on more than one front from stressors such as rising ocean temperatures, poor water quality and pollution.

“To effectively look after these coastal ecosystems, managers need a thorough understanding of the effects these human induced changes have, both individually and in combination.”

Associate Professor Chris Brown, head of the Seascape Models group at Australian Rivers Institute and the Coastal and Marine Research Centre lamented that “to-date most attempts to discover of how such stressors interact, using data pooled from multiple studies, have failed to find consistent predictions for combined effects.”

Cystic fibrosis: restoring airway integrity

Hydration restores the airway surface seal. In turquoise, the junctions between the epithelial cells (blue).
Credit: UNIGE - Laboratory of Prof. Marc Chanson

Cystic fibrosis is a rare genetic disease which can cause very serious symptoms. In particular, patients suffer from chronic bacterial infections that can lead to respiratory failure. It is caused by mutations in the CFTR gene, which regulates water movement across the cell membrane. Consequently, mucus quality is altered, it is no longer capable of capturing undesirable bacteria and expelling them. Using a model reproducing a respiratory epithelium - a protective tissue composed of a monolayer of cells - teams from the University of Geneva (UNIGE) have discovered that a simple film of liquid is sufficient to restore the airways’ seal and reduce the risk of bacterial infection. These results, to be read in a special issue of the journal Cells, open the way to new therapies based on mucus hydration. A promising alternative to current therapies that are often not widely enough effective.

Despite recent therapeutic advances, people with cystic fibrosis — one in every 2,500 births in Europe — have a life expectancy of no more than 46 years and altered quality of life. The disease is caused by one or more mutations in the CFTR gene, which affects the proper functioning of an essential protective barrier. The epithelial cells that line the airways are usually sealed together and thus protect the airways from bacterial colonization. They are also lined with a fluid, a slippery mucus that traps unwanted germs and carries them away. When the CFTR protein is altered, the junctions between the cells loosen and the dehydrated mucus tends to stagnate, both of which promote the development of respiratory

A family of termites has been traversing the world’s oceans for millions of years

Credit: Aleš Buček

A new study has mapped out the natural history of drywood termites—the second largest family of termites.

Drywood termites form small colonies primarily in wood and are generally thought of as primitive termites but very little is actually known about the family.

By sequencing the mitochondrial genomes of 120 species found across the world, the researchers discerned that this family has made at least 40 oceanic voyages in the last 50 million years.

The study also confirmed that some species have, in recent centuries, hitched a ride with humans to reach far-flung islands.

Furthermore, it cast doubt on the common assumption that drywood termites have a primitive lifestyle as, among the oldest lineages in the family, there are species that do not exhibit this lifestyle.

Planets of binary stars as possible homes for alien life

The ALMA telescopes in Chile
Credit: ESO/S. Guisard

Since the only known planet with life, the Earth, orbits the Sun, planetary systems around stars of similar size are obvious targets for astronomers trying to locate extraterrestrial life. Nearly every second star in that category is a binary star. A new result from research at University of Copenhagen indicates that planetary systems are formed in a very different way around binary stars than around single stars such as the Sun.

“The result is exciting since the search for extraterrestrial life will be equipped with several new, extremely powerful instruments within the coming years. This enhances the significance of understanding how planets are formed around different types of stars. Such results may pinpoint places which would be especially interesting to probe for the existence of life,” says Professor Jes Kristian Jørgensen, Niels Bohr Institute, University of Copenhagen, heading the project.

The results from the project, which also has participation of astronomers from Taiwan and USA, are published in the distinguished journal Nature.

Target CO2 and non-carbon pollutants to slow climate change

Photo: Pixabay

Policies that focus solely on decarbonization will not be sufficient to keep the Earth’s temperature below the “tipping point” threshold scientists have long warned could result in a runaway greenhouse warming effect, according to research published May 23 in the Proceedings of the National Academy of Sciences.

While carbon dioxide is the chemical most responsible for climate change, four other pollutants – methane, black carbon soot, lower-atmosphere ozone smog and hydrofluorocarbon refrigerants – contribute almost half the heat trapped to-date that cause global warming.

Reducing atmospheric levels of all of these pollutants, known as super pollutants, will be necessary to keep global temperatures from rising beyond 1.5 degrees Celsius above pre-industrial levels, the internationally accepted guardrail beyond which the world’s climate is expected to pass irreversible tipping points.

Monitoring the "journey" of microplastics through the intestine of a living organism

Drosophila melanogaster 
Credit: Universitat Autònoma de Barcelona

A UAB research team has managed to track the behavior of microplastics during their "journey" through the intestinal tract of a living organism and illustrate what happens along the way. The study, carried out on Drosophila melanogaster using electron microscopy equipment developed by the researchers themselves, represents a significant step towards a more precise analysis of the health risks of being exposed to these pollutants.

The behavior of micro and nanoplastics (MNPLs) inside the organism is a question impossible to answer at present in humans, and in vitro models are not useful. Hence, there is a need to look for models that allow us to answer this question. Furthermore, there are limitations in the current methodologies for detecting and quantifying their presence in different human biological samples, which prevents an accurate assessment of the health risk of exposure.

In this context, researchers from the Mutagenesis Research Group of the Universitat Autònoma de Barcelona (UAB) have managed to monitor the tracking of MNPLs in their "journey" from the environment to the interior of a living organism. They have done it by developing tools based on electron microscopy and in larvae of the Drosophila melanogaster fly, a model organism widely used to study biological phenomena and processes.

Skydiving salamanders live in world’s tallest trees

The wandering salamander, Aneides vagrans, is about 4 inches (10 centimeters) long and lives its entire life in the crowns of redwood trees more than 150 feet above the ground. Researchers discovered that it has adapted to its high-rise lifestyle by developing the ability to parachute and glide when falling.
Photo credit: Christian Brown

Salamanders that live their entire lives in the crowns of the world’s tallest trees, California’s coast redwoods, have evolved a behavior well-adapted to the dangers of falling from high places: the ability to parachute, glide and maneuver in mid-air.

Flying squirrels, not to mention numerous species of gliding frogs, geckos, ants, and other insects, are known to use similar aerial maneuvers when jumping from tree to tree or when falling, so as to remain in the trees and avoid landing on the ground.

Similarly, the researchers suspect that this salamander’s skydiving skills are a way to steer back to a tree it’s fallen or jumped from, the better to avoid terrestrial predators.

The drug gabapentin may boost functional recovery after a stroke

These 3D images of mouse brain vasculature show normal conditions, top, and after an ischemic stroke, which occurs when a blood vessel clot blocks blood flow in the brain.
Credit: Andrea Tedeschi

The drug gabapentin, currently prescribed to control seizures and reduce nerve pain, may enhance recovery of movement after a stroke by helping neurons on the undamaged side of the brain take up the signaling work of lost cells, new research in mice suggests.

The experiments mimicked ischemic stroke in humans, which occurs when a clot blocks blood flow and neurons die in the affected brain region.

Results showed that daily gabapentin treatment for six weeks after a stroke restored fine motor functions in the animals’ upper extremities. Functional recovery also continued after treatment was stopped, the researchers found.

The Ohio State University team previously found that gabapentin blocks the activity of a protein that, when expressed at elevated levels after an injury to the brain or spinal cord, hinders re-growth of axons, the long, slender extensions of nerve cell bodies that transmit messages.

Medicine for Inflammatory Bowel Disease May Protect Against Severe COVID-19

Gil Melmed, MD

Getting the COVID-19 vaccination strengthened one type of immune response to the SARS-CoV-2 virus in inflammatory bowel disease

(IBD) patients even though they were taking immunosuppressant medication, according to investigators at Cedars-Sinai.

The findings of two studies focused on this topic have been published in the journals IBD, of the Crohn’s & Colitis Foundation, and Frontiers in Immunology.

“We found that with COVID-19 vaccination most of the main immunosuppressive treatments for IBD preserved the T-cell response, with one notable exception: anti-tumor necrosis factor (anti-TNF) drug therapy. This biologic treatment actually elevated T-cell activity in the vaccinated patients. We think this may help protect them from severe disease after breakthrough infection,” said Gil Melmed, MD, principal investigator of the study and director of Inflammatory Bowel Disease Clinical Research at Cedars-Sinai.

New Tech Aims to Drive Down Costs of Hydrogen Fuel

Researchers from North Carolina State University have developed a new technique for extracting hydrogen gas from liquid carriers which is faster, less expensive and more energy efficient than previous approaches.

“Hydrogen is widely viewed as a sustainable energy source for transportation, but there are some technical obstacles that need to be overcome before it can be viewed as a practical alternative to existing technologies,” says Milad Abolhasani, corresponding author of a paper on the new technique and an associate professor of chemical and biomolecular engineering at NC State. “One of the big obstacles to the adoption of a hydrogen economy is the cost of storage and transportation.”

Hydrogen fuel does not result in CO2 emissions. And hydrogen refueling stations could be located at existing gas stations, taking advantage of existing infrastructure. But transporting hydrogen gas is dangerous, so hydrogen needs to be transported via a liquid carrier. A key obstacle for this strategy is that extracting hydrogen from the liquid carrier at destination sites, such as fueling stations, is energy intensive and expensive.

“Previous research has shown that it is possible to use photocatalysts to release hydrogen gas from a liquid carrier using only sunlight,” Abolhasani says. “However, existing techniques for doing this were laborious, time consuming and required a significant amount of rhodium – a metal that is very expensive.”