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Comment by Dr. Krishna Kumari Challa on October 17, 2024 at 9:32am

Plastic pollution harms bees and their pollinator functions, research team finds

Nano- and microplastic particles (NMP) are increasingly polluting urban and rural landscapes, where bees and other beneficial insects come into contact with them. If insects ingest plastic particles from food or the air, it can damage their organs and cause changes in their behavior, preventing them from properly performing ecosystem services such as pollination and pest control.

Plastic pollution thus poses considerable risks to biodiversity, agricultural production, and global food security. These are the main findings of a new review in the journal Nature Communications, which was conducted by an international team of researchers .

Microplastic particles are between one micrometer and five millimeters in size; still smaller particles are referred to as nanoplastics. Whereas the harmful effects of NMP in water and for individual species are well documented, there have as yet been no systematic reviews on how the particles affect agricultural ecosystems.

To fill this gap, the authors of the review summarized 21 already published individual studies for the first time. They were interested particularly in the question of how pollinator insects and other beneficial insects come into contact with NMP and what consequences the ingestion of the particles has for them, as well as for the ecosystems that are dependent on them and for agricultural production. 

In this way, the researchers first succeeded in identifying different sources from which NMP end up on agricultural land, including plastic films, fertilizers, polluted water, and atmospheric depositions. The plastic particles accumulate in the soil, and pollinators and beneficial insects that are important for pest control ingest them from the air and food or use them to build nests.

The authors of the study establish that the bees' ingestion of NMP leads, for example, to damage to their digestive system, to a weakening of their immune system, and to changes in their behavior. This makes the bees more susceptible to diseases, possibly causing them to pollinate plants less effectively. This leads to decline in agriculture production.

A decline in pollination services has a negative effect on crop yield. Thus, plastic pollution could further aggravate existing uncertainties in the global food supply, the researchers warn.

In addition, NMP also exacerbates the threats posed by other environmental stressors, such as pesticides, chemical pollution, fungi, and pathogens. For example, some areas become "hotspots," where plastic particles interact with harmful viruses. As a result of such interactions, NMP could have serious effects on pollinators and thus on the stability of the food system.

It is already clear today, however, that there is a pressing need for political control of plastic pollution, the researchers stress.

 Dong Sheng et al, Plastic pollution in agricultural landscapes: an overlooked threat to pollination, biocontrol and food security, Nature Communications (2024). DOI: 10.1038/s41467-024-52734-3

Comment by Dr. Krishna Kumari Challa on October 17, 2024 at 8:51am

Researchers call for PFAS ban after alarming findings in marine environments

Washing your pots and pans—among many other day-to-day activities—could have a significant impact on marine environments for hundreds of years, according to a new study.

Scientists have partnered with the  leading marine membership charities to investigate the presence of harmful chemicals in a protected area. They found that sewage discharges are contributing significantly to per- and polyfluoroalkyl substances (PFAS) in marine environments.

PFAS are a complex group of nearly 15,000 synthetic substances used in consumer products around the world since the 1950s. They keep food from sticking to packaging or cookware, make clothes and carpets resistant to stains, and are found in firefighting foam.

The "forever chemicals" don't break down easily in the environment. They have been linked to adverse effects on human health and wildlife.

Wastewater treatment plants (WWTPs) are not effective at removing PFAS, and therefore they are often released into the environment through combined sewer overflows (CSOs).

The findings of the study, published in Chemosphere, revealed PFAS concentrations increased significantly after sewage discharges. Eight different PFAS compounds were detected post-discharge, compared to just one detectable compound before the discharge.

Banned substances Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were also found at levels exceeding annual average environmental quality standards.

The paper raises concerns about the health of marine ecosystems and the potential impacts of industries using seafood products.

Samples also showed the amount of one particular PFAS called Perfluorobutanoic acid (PFBA) in the seaweed was more than 6,000 times higher than the amount found in the surrounding water.

These seaweeds could potentially be acting as a reservoir for these forever chemicals around our coasts. High concentrations of PFAS compounds in macroalgae might be harmful for marine life that graze on seaweed and as a result provide a trophic link up the food chain.

Toxicity studies in the laboratory and human epidemiological studies of those drinking PFAS contaminated water have highlighted these chemical compounds can impact the immune, nervous and reproductive systems as well as being carcinogenic and cause birth defects.

"It is important that we get these chemicals banned as we are still seeing the impacts of persistent chemical contaminants—like PCBs—impacting wildlife that were banned decades ago, which is why it is so important we act faster, the researchers say.

 Alex T. Ford et al, Insights into PFAS contaminants before and after sewage discharges into a marine protected harbour, Chemosphere (2024). DOI: 10.1016/j.chemosphere.2024.143526

Comment by Dr. Krishna Kumari Challa on October 17, 2024 at 8:40am

Study finds PFAS in fish far from contamination sources

Fish can accumulate high levels of per- and polyfluoroalkyl substances (PFAS), even far from sources of contamination, according to a new study by researchers .

This study underscores the urgent need for more comprehensive monitoring of PFAS in aquatic ecosystems, particularly in regions where freshwater fishing is an important food source .

PFAS, also called forever chemicals because of their persistence in the environment, are a family of thousands of synthetic chemicals widely used for their stain-resistant, water-resistant, non-stick properties. They have seeped into our water, soil, and food, and can be found in more than 98-99% of people in some countries. 

 Freshwater fish and shellfish, a staple in many diets, often contain high levels of these forever chemicals.

The results of the study were striking: PFAS concentrations in fish tissues remained alarmingly high, even up to 8 km from the source. Despite some decline in concentration with distance, fish filet samples consistently exceeded  guidelines for safe fish consumption based on PFOS levels alone, without accounting for other PFAS identified in the samples.

The researchers found that a substantial portion of PFAS contamination remains undetected by conventional monitoring techniques, which typically target only a limited number of PFAS compounds. To fully grasp the scale of PFAS contamination and its risks, environmental monitoring programs and fish consumption advisories must include a wider range of PFAS compounds, the researchers recommend.

Heidi M. Pickard et al, Characterizing the Areal Extent of PFAS Contamination in Fish Species Downgradient of AFFF Source Zones, Environmental Science & Technology (2024). DOI: 10.1021/acs.est.4c07016

https://www.sciencedirect.com/science/article/abs/pii/S004565352302...

Comment by Dr. Krishna Kumari Challa on October 16, 2024 at 11:07am

‘Neural tourniquet’ could stem bleeding

Electrical stimulation near the ear that targets the vagus nerves might help to reduce bleeding during surgery or childbirth. The ‘neural tourniquet’ seems to stimulate the spleen, which stores about one-third of the body’s clot-forming platelets, according to preliminary results presented at the 2024 Society for Neuroscience conference. Tests in injured pigs and mice with the blood-clotting condition haemophilia showed that the animals bled less, and for less time, than untreated ones. The time scale could be a real-world limitation for emergency treatment: platelets were most highly activated 2 hours after stimulation.

https://www.nature.com/articles/d41586-024-03330-4?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on October 16, 2024 at 8:58am

The physics of red blood cells in bats could be a key to 'artificial hibernation' for humans

The mechanical properties of red blood cells (erythrocytes) at various temperatures could play an important role in mammals' ability to hibernate. This is the outcome of a study that compared the thermomechanical properties of erythrocytes in two species of bats and humans.

The study was published in October 2024 in the Proceedings of the National Academy of Sciences. The new findings could contribute towards the development of new medical treatments.

Hibernation is common for mammals, especially bats, and even some primates hibernate. In this current study, the interdisciplinary team of researchers compared the mechanical properties of hundreds of thousands of individual erythrocytes from a hibernating native bat species, the common noctule (Nyctalus noctula), a non-hibernating bat species, the Egyptian fruit bat (Rousettus aegyptiacus), and healthy human donors. Data was collected for temperatures between 10°C and 37°C.

In all three species, the individual erythrocytes became more viscous when the temperature of the blood samples was lowered from a normal body temperature of 37°C to a temperature of 10°C, which is typical for temperatures in hibernating mammals.

The observed behaviour is a result of the properties of the cell membrane and is much more evident in both bat species than in humans. Interestingly, this special adaptation in bats is not only due to seasonal fluctuations such as changing diets and surrounding temperatures.

Humans are unable to significantly lower their core body temperature in order to save energy. Based on the collected data, it could be possible in the future to develop pharmaceutical methods that change the mechanical properties of human erythrocytes in order to optimize the blood circulation in artificially induced states similar to hibernation. If this is successful, the dream of hibernation for extended space missions could also come a step closer to reality.

Bob Fregin et al, Thermomechanical properties of bat and human red blood cells—Implications for hibernation, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2405169121

Comment by Dr. Krishna Kumari Challa on October 16, 2024 at 8:45am

This is really Funny! 

Male mice use female mice to distract aggressors and avoid conflict, study shows

A research group tracked the behaviour of mice using machine learning to understand how they handle aggressive behaviour from other mice. The researchers' findings, published on October 15 in the open-access journal PLOS Biology, show that male mice deescalate aggressive encounters by running over to a female mouse to distract the aggressive male mouse.

The researchers recorded groups of two male and two female mice interacting over five hours. Like many other animals, mice have social hierarchies, and in almost each group recorded, one male was always significantly more aggressive towards the other.

Social interactions can be challenging to study objectively, so the researchers used a machine learning approach to analyze aggressive interactions and how the mice respond. In total, they observed over 3,000 altercations between the male mice, and the machine learning algorithm helped researchers determine the most likely responses to aggression and whether these actions resolved or furthered the conflict.

The researchers found that the male mouse who was aggressively encountered often ran over to one of the female mice and that this deescalated the aggression. This may be a "bait-and-switch" tactic, as the aggressive male mouse typically followed the other male but then interacted with the female mouse instead of continuing the aggressive encounter.

Some other tactics, even if they avoided aggression for a moment, would then escalate to full fights. However, the researchers found this was not the case after the bait-and-switch. After this tactic was used, fights rarely occurred, the male mice often remaining further apart from each other with the aggressive mouse continuing to interact with the female mouse.

While the bait-and-switch may be an effective way to deescalate conflicts, there may be costs to the victim, such as sacrificing time with the female mice, and further research may look into whether these tactics are effective in larger groups of mice.

Clein RS, Warren MR, Neunuebel JP, Mice employ a bait-and-switch escape mechanism to de-escalate social conflict, PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002496

Comment by Dr. Krishna Kumari Challa on October 16, 2024 at 8:34am

A video that really explains how color works

Comment by Dr. Krishna Kumari Challa on October 15, 2024 at 11:28am

Amazing Moment as SpaceX Catches Giant Starship Booster

For the first time ever, SpaceX has followed through on a Starship test launch by bringing back the Super Heavy booster for an on-target catch in the arms of its "Mechazilla" launch-tower cradle .

Today's successful catch marks a giant step toward using — and reusing — Starship for missions ranging from satellite deployments to NASA's moon missions to migrations to Mars.

The amazing catch took place minutes after Super Heavy lofted Starship's second stage, known as Ship, into space for the launch system's fifth test flight. Liftoff occurred at 7:25 a.m. CT (1225 UTC) at SpaceX's Starbase on the South Texas coast.

Although the primary objective of the test was to have Ship survive atmospheric re-entry and splash down intact in the Indian Ocean, the Super Heavy booster was the star of the show.

Comment by Dr. Krishna Kumari Challa on October 15, 2024 at 9:07am

As the mice gradually learned to complete the perceptual learning task, the researchers stimulated their vagus nerve using the electrode they developed. Concurrently, they also recorded activity in the animals' auditory cortex (involved in processing sounds), as well as in the locus coeruleus of the brainstem and the basal forebrain, two regions implicated in attention.

They found that indeed, VNS could augment training and improve perceptual discrimination beyond the limit achieved by training and effort alone. However, it takes a while, a few weeks of daily training and stimulation to see enduring gains at the most challenging difficulty levels. They also identified neural changes supporting this perceptual improvement..
The evidence gathered by the team at New York University suggests that in mice VNS activates the central cholinergic system, a neural network that utilizes the neurotransmitter acetylcholine to communicate with other neurons and supports various brain functions. The activation of this neural network was found to in turn enhance the performance of mice in the perceptual learning task they developed.

 Kathleen A. Martin et al, Vagus nerve stimulation recruits the central cholinergic system to enhance perceptual learning, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01767-4.

Part 2

Comment by Dr. Krishna Kumari Challa on October 15, 2024 at 9:06am

Vagus nerve stimulation enhances perceptual learning in mice, study suggests

Recent neuroscience studies have been investigating how the stimulation of some nerves, particularly the vagus nerve, using electrical pulses affects neural activity in the mammalian brain. The vagus nerve, the longest cranial nerve in the human body, is known to play a key role in the regulation of heart rate, digestion, stress and other physiological processes.

Some findings suggest that stimulating the vagus nerve can enhance the plasticity of the brain, which is its ability to reorganize itself following experiences. This could in turn facilitate perceptual learning, the process by which humans and other animals become better at distinguishing and interpreting different sensory inputs.

Researchers at New York University School of Medicine set out to further examine the effects of vagus nerve stimulation (VNS) on neural activity and perceptual learning in mice. Their findings, published in Nature Neuroscience, suggest that stimulating the vagus nerve enhances the performance of mice on a perceptual learning task by activating the central cholinergic system.

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