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Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:53pm

In the hardened and inflexible stomach of a plastic-filled shearwater, room for new food is limited and digestion seems to be severely impacted. With so much scar tissue, scientists say the lining of the internal organ is not nearly as good at secreting digestive enzymes or absorbing nutrients.

The resulting loss of nourishment could be a key reason why so many shearwaters on Lord Howe are underweight. Since 2010, their average body mass has plummeted. And in the current study, higher numbers of plastic pieces in a shearwater's stomach were associated with a lower overall body weight.

"The tubular glands, which secrete digestive compounds, are perhaps the best example of the impact of plasticosis.

"When plastic is consumed, these glands get gradually more stunted until they eventually lose their tissue structure entirely at the highest levels of exposure."

The consequences of ingesting plastic may not be the same for all seabird stomachs, or even all animal stomachs, but given the ubiquitous nature of ingested plastic in the marine food web, there's reason to worry about the health effects.

In humans, recent studies have shown people with inflammatory bowel disease (IBD) tend to have elevated levels of microplastics in their feces.

Among 52 participants, greater plastic exposure was closely aligned with the worst IBD symptoms.

That study was only small and does not establish cause and effect, but since microplastics have been found in human blood, placenta, feces, and the deepest parts of our lungs, toxicologists say we need urgent health assessments.

Ingested plastic can not only cause physical damage, it can also provide a way for parasites and microbes to hitchhike into the body. In addition, as plastics degrade, they may leech toxic and persistent chemicals with potentially dangerous health effects.

Part 2

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:51pm

'Plasticosis': The First Disease Caused by Ingested Plastic Was Just Described by Scientists

One of the most plastic-contaminated birds in the whole world is silently suffering from a novel, emerging disease scientists have coined 'plasticosis'.

It's reportedly the first time researchers have ever documented and quantified the pathological effects of ingested plastic in wild animals, and it's got scientists stressing about the health of more than just one species.

The new findings suggest sharp plastic fragments can literally tear some seabirds apart from the inside.

This new  study clearly demonstrates the ability of plastic to directly induce severe, organ-wide scar tissue formation or 'plasticosis' in wild, free-living animals, which is likely to be detrimental to individual health and survival, acccording to reporters. 

When it comes to physical damage caused by ingested plastic, flesh-footed shearwaters (Ardenna carneipes) are the canaries in the coal mine.

Despite the sheer distance from human civilization, many of the chicks hatched on Lord Howe are suffering a slow and sickly death that seems to be all our fault.

Each autumn, gaunt and bedraggled fledglings litter the island's beaches, and for years now, scientists have been trying to figure out why so many of these seabirds are sick and dying.

When researchers examined the carcasses of dozens of dead birds from Lord Howe, they found excessive and irreversible signs of scar tissue in stomach after stomach. The extensive internal scarring is most likely caused by tiny bits of sharp plastic digging into a bird's internal lining over and over. Without the chance to heal, the first chamber of the bird's stomach, called the proventriculus, grows distorted with damage.

Sometime back researchers described about a bird stomach so full of plastic it was "bulging… almost rupturing". The scientists conducting the necropsy counted 202 plastic pieces in total.

That's hardly an exceptional circumstance. Roughly 90 percent of necropsied birds on Lord Howe island have contained plastic in their stomachs.

The consistent scarring and chronic inflammation observed in seabird stomachs filled with plastic has scientists thinking this is a specific fibrotic disease.

They've called it 'plasticosis' to keep in line with other fibrotic diseases, like silicosis and asbestosis, which are also marked by tissue damage from pollutants, except in these cases the damage occurs in the lungs.

lab studies have shown that sharp, ingested macroplastics, around 5 millimeters in size, can block, ulcerate, or perforate digestive tracts, while also reducing feeding behavior. In severe cases, the animal can even starve to death.

The study among shearwaters is the first to show plasticosis occurring among wild animals.

Part 1

Comment by Dr. Krishna Kumari Challa on March 5, 2023 at 2:35pm

Scientists found a way to generate new neurons in the brain

Some areas of the adult brain contain quiescent, or dormant, neural stem cells that can potentially be reactivated to form new neurons. However, the transition from quiescence to proliferation is still poorly understood. A research team  has discovered the importance of cell metabolism in this process and identified how to wake up these neural stem cells and reactivate them.

Biologists succeeded in increasing the number of new neurons in the brain of adult and even elderly mice. These results, promising for the treatment of neurodegenerative diseases, are to be discovered in the journal Science Advances.

Stem cells have the unique ability to continuously produce copies of themselves and give rise to differentiated cells with more specialized functions. Neural stem cells (NSCs) are responsible for building the brain during embryonic development, generating all the cells of the central nervous system, including neurons.

Surprisingly, NSCs persist in certain brain regions even after the brain is fully formed and can make new neurons throughout life. This biological phenomenon, called adult neurogenesis, is important for specific functions such as learning and memory processes. However, in the adult brain, these stem cells become more silent or "dormant" and reduce their capacity for renewal and differentiation.

As a result, neurogenesis decreases significantly with age. Researchers have uncovered a metabolic mechanism by which adult NSCs can emerge from their dormant state and become active again.

They found that mitochondria, the energy-producing organelles within cells, are involved in regulating the level of activation of adult NSCs.

 The mitochondrial pyruvate transporter (MPC), a protein complex discovered eleven years ago, plays a particular role in this regulation. Its activity influences the metabolic options a cell can use. By knowing the metabolic pathways that distinguish active cells from dormant cells, scientists can wake up dormant cells by modifying their mitochondrial metabolism.

Biologists have blocked MPC activity by using chemical inhibitors or by generating mutant mice for the Mpc1gene. Using these pharmacological and genetic approaches, the scientists were able to activate dormant NSCs and thus generate new neurons in the brains of adult and even aged mice.

These results shed new light on the role of cell metabolism in the regulation of neurogenesis. In the long term, these results could lead to potential treatments for conditions such as depression or neurodegenerative diseases.

Francesco Petrelli, Valentina Scandella, Sylvie Montessuit, Nicola Zamboni, Jean-Claude Martinou, Marlen Knobloch. Mitochondrial pyruvate metabolism regulates the activation of quiescent adult neural stem cells. Science Advances, 2023; 9 (9) DOI: 10.1126/sciadv.add5220

Comment by Dr. Krishna Kumari Challa on March 5, 2023 at 2:02pm

Hubble’s Inside The Image: V838

Comment by Dr. Krishna Kumari Challa on March 4, 2023 at 2:10pm

6174 is known as Kaprekar's constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule:

1. Take any four-digit number, using at least two different digits (leading zeros are allowed).
2. Arrange the digits in descending and then in ascending order to get two four-digit numbers, adding leading zeros if necessary.
3. Subtract the smaller number from the bigger number.
4. Go back to step 2 and repeat.

The above process, known as Kaprekar's routine, will always reach its fixed point, 6174, in at most 7 iterations. Once 6174 is reached, the process will continue yielding 7641 – 1467 = 6174. For example, choose 1459:

9541 – 1459 = 8082

8820 – 0288 = 8532

8532 – 2358 = 6174

7641 – 1467 = 6174

The only four-digit numbers for which Kaprekar's routine does not reach 6174 are repdigits such as 1111, which give the result 0000 after a single iteration. All other four-digit numbers eventually reach 6174 if leading zeros are used to keep the number of digits at 4. For numbers with three identical numbers and a fourth number that is one number higher or lower (such as 2111), it is essential to treat 3-digit numbers with a leading zero; for example: 2111 – 1112 = 0999; 9990 – 999 = 8991; 9981 – 1899 = 8082; 8820 – 288 = 8532; 8532 – 2358 = 6174.

6174 (number) - Wikipedia

Comment by Dr. Krishna Kumari Challa on March 4, 2023 at 1:25pm

Black Hole Mergers

Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 12:30pm

Boat strikes can be deadly for whale populations all over the world The surge in online shopping that began during the pandemic has led to an increase in cargo ships hauling those goods across the Atlantic to the busy Port of New York and New Jersey. Those ships, larger than they were in the past in order to carry more shipping containers, are also taking new routes in an effort to avoid clogging up shipping lanes like in years past, according to The Times. The Port Authority of New York and New Jersey saw a 27 percent increase in volume last year compared to 2019 levels, and shipping traffic along the East Coast has increased as boats have started making down-and-back trips to retrieve empty shipping containers. While NOAA has proposed speed limits, which could give whales time to move out of the way of oncoming ships, the fact remains that whales are always going to follow their food. "When the whales are in these channels, you have to cross your fingers and hope there are no collisions," Paul Sieswerda, executive director of New York City-based research group Gotham Whale, told The Times. Boat strikes can cause internal injuries from the blunt force trauma, and their propellers can inflict large gashes. Two whales that washed up dead along the Atlantic Coast this month were determined to have been struck by vessels, USA Today reported. This isn't the first time experts have raised the alarm about ships harming whale populations. A year ago, scientists began calling for cargo ships to start rerouting in order to protect endangered blue whales that live off the coast of Sri Lanka. Mediterranean Shipping Company, the largest container line in the world, complied with the request, and animal welfare groups said at the time that if other companies followed, it could reduce ship strikes by 95 percent. This article was originally published by Business Insider.

https://www.sciencealert.com/a-rise-in-online-shopping-partially-to...

Part 2

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Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 12:29pm

A Rise in Online Shopping Partially to Blame For Recent Spike in Whale Deaths

Our addiction to online shopping is contributing to the recent spike in whale deaths, The New York Times reports.

Since early December, 23 whales have washed up dead along the East Coast, according to data the National Oceanic and Atmospheric Administration provided to The Times. Their deaths are due to a confluence of factors, both environmental and the result of human interference.

NOAA has been tracking an "unusual mortality event" among the Atlantic Coast humpback whale population since 2016, but the recent spike in whale deaths – which has included humpback whales, minke whales, and North Atlantic right whales, which are critically endangered – prompted the NOAA Fisheries to address the crisis during a call with reporters in January.

Lauren Gaches, the agency's public affairs director, said during the call that climate change is partly to blame for the number of whales washing up dead, because warming oceans are causing the fish they eat to move closer to shore.

"We're seeing populations of many marine species adapting by moving into new areas where conditions are more favorable," Gaches said.

"Changing distributions of prey impact larger marine species that depend on them. This can lead to increased interactions with humans as some whales move closer to near-shore habitats."

Which means as some whales seek out prey, they're moving into the path of cargo ships, which have gotten bigger and more plentiful over the past three years.

Part 1

Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 11:56am

Understanding the role quantum tunneling plays in the building and rearrangements of molecules could have important ramifications in the calculations of energy release in nuclear reactions, such as those involving hydrogen in stars and fusion reactors here on Earth.

While we've modeled this phenomenon for examples involving reactions between a negatively charged form of deuterium – an isotope of hydrogen containing a neutron – and dihydrogen or H₂, proving the numbers experimentally requires a challenging level of precision.

To accomplish this, Wild and his colleagues cooled negative deuterium ions to a temperature that brought them close to a standstill before introducing a gas made of hydrogen molecules.

Without heat, the deuterium ion was far less likely to have the energy required to force hydrogen molecules into a rearrangement of atoms. Yet it also forced the particles into sitting quietly near one another, giving them more time to bond through tunneling.

In their experiment, scientists give possible reactions in the trap about 15 minutes and then determine the amount of hydrogen ions formed. From their number, they can deduce how often a reaction has occurred.

That figure is just over 5 x 10^-20 reactions per second taking place in each cubic centimeter, or around one tunneling event for around every hundred billion collisions. So not a lot. Though the experiment does back up previous modeling, confirming a benchmark that can be used in predictions elsewhere.

Given tunneling plays a fairly important role in a diverse range of nuclear and chemical reactions, much of which is also likely to occur out in the cold depths of space, getting a precise grip on the factors at play gives us a more solid grounding to base our predictions on.

https://www.nature.com/articles/s41586-023-05727-z

part 2

Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 11:54am

For The First Time Ever, Physicists See Molecules Form Through Quantum Tunneling

Chemistry takes effort. Whether it's by raising the temperature, increasing the odds that compatible atoms will collide in a heated smash-up, or increasing the pressure and squeezing them together, building molecules usually demands a certain cost in energy.

Quantum theory does provide a workaround if you're patient. And a team of researchers from the University of Innsbruck in Austria has finally seen the quantum tunneling in action in a world-first experiment measuring the merger of deuterium ions with hydrogen molecules.

Tunneling is a quirk of the quantum universe that makes it seem like particles can pass through obstacles that are ordinarily too hard to overcome.

In chemistry, this obstacle is the energy required for atoms to bond with one another, or with existing molecules.

Yet theory says that, in extremely rare instances, it's possible for atoms in close proximity to 'tunnel' their way through this energy barrier and connect without any effort.

Quantum mechanics allows particles to break through the energetic barrier due to their quantum mechanical wave properties, and a reaction occurs.

Quantum waves are the ghosts that drive the behaviors of objects like electrons, photons, and even entire groups of atoms, blurring their existence before any observation so they sit not in any one precise place but occupy a continuum of possible positions.

This blurring is insignificant for larger objects like molecules, cats, and galaxies. But as we zoom in on individual subatomic particles, the range of possibilities expands, forcing the location states of various quantum waves to overlap.

When that happens, particles have a slight chance of appearing where they have no business being, tunneling into regions that would otherwise require a great deal of force to enter.

One of those regions for an electron might be within the bonding-zone of a chemical reaction, welding together neighboring atoms and molecules without the boom-crash-crush of heat or pressure.

part1

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