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Comment by Dr. Krishna Kumari Challa on May 28, 2025 at 3:35pm

Trees May Be Able to Warn Us When a Volcano Is About to Erupt

The science of predicting volcanic eruptions can genuinely save lives – potentially, a lot of lives – and researchers have shown that tree leaf colors can act as warning signals around a volcano that's about to blow. As volcanoes get more active and closer to an eruption, they push magma up closer to the surface, releasing higher levels of carbon dioxide. That in turn can boost the health of the surrounding trees, making leaves greener. And those changes – specifically in the measurement known as the normalized difference vegetation index (NDVI) – can be spotted by satellites in space. We could be looking at an early warning system for eruptions that doesn't require any local field work or ground sensors, so it could work in remote and difficult-to-access areas.

https://www.sciencedirect.com/science/article/abs/pii/S003442572400...

Comment by Dr. Krishna Kumari Challa on May 28, 2025 at 2:42pm

Silent X chromosome awakens with age: New explanation for sex differences in age-related diseases

Women age differently from men when it comes to health—particularly in conditions like cardiovascular disease and neurodegenerative disorders such as dementia and Parkinson's.

A research team proposed a new explanation for this. In aging female mice, genes on the previously silenced second X chromosome become active again. This mechanism might also influence women's health later in life. The study is published in the journal Nature Aging.

Unlike men, who carry one X and one Y chromosome, women have two X chromosomes in each cell. However, one of the two X chromosomes is effectively silenced. It folds into a compact structure known as the Barr body and can no longer be read. Without this mechanism, the genes on the X chromosome would be read twice as often in women as in men.

Scientists have known for some time that some genes can escape inactivation in the Barr body, resulting in higher gene activity in women. These genes are suspected to influence disease.

Researchers have now shown for the first time that with increasing age, more and more genes escape the inactivation of the Barr body.

The researchers examined the major organs of mice at different stages of life. In the older animals, the proportion of genes that had escaped was on average twice as high as in adult animals—6% instead of 3% of the genes on the X chromosome. In some organs, the numbers were even higher: in the kidneys, for instance, nearly 9%.

With aging, epigenetic processes gradually loosen the tightly packed structure of the inactive X chromosome. This mainly happens at the ends of the chromosome, allowing for genes located in those regions to be read again.

Many of the genes that become active again with age are associated with disease. These new  findings are based on mice, but since the X chromosome is very similar in humans,  the same may happen in aging women. 

According to the researchers, this doubled gene activity could have positive effects in some cases and negative effects in others.

ACE2, for example—a gene that escapes in the lungs with age—can help limit pulmonary fibrosis. Increased activity of the gene TLR8 in old age, however, may play a role in autoimmune diseases such as late-onset lupus.

Sex differences in age-related disease are incredibly complex.

So far, scientific explanations have mostly focused on hormonal or lifestyle factors. While the role of the X chromosome and some escape genes have been studied before, the discovery that many genes on the inactive X can reactivate with age opens up entirely new lines of research.

Sarah Hoelzl et al, Aging promotes reactivation of the Barr body at distal chromosome regions, Nature Aging (2025). DOI: 10.1038/s43587-025-00856-8

Comment by Dr. Krishna Kumari Challa on May 28, 2025 at 2:24pm

Scientists have attempted to expand its scope to active imaging applications such as light detection and ranging or LiDAR, but the lack of suitable thermal light sources and robust image reconstruction algorithms make the process challenging.

To overcome these issues, the researchers created an intensity interferometer setup with pseudothermal illumination achieved by superimposing light from 8-phase-independent multiple laser emitters. This setup included two telescopes and an infrared laser system on a shared optical bench.

The laser system produced thermal illumination, and reconstructed sparse, noisy data being collected into a high-resolution image with the help of a computational algorithm.

To test the super-resolution capabilities of the device, the letters "USTC" were crafted out of hollowed-out blackened aluminum sheets which were then covered in retroreflective sheets and used as a complex imaging target positioned over a kilometer away.
Using the designed active intensity interferometer, the researchers successfully demonstrated super-resolution imaging of millimeter-scale targets at a distance of 1.36 km in an outdoor urban environment. The imaging system achieved a resolution of 3 mm, which is 14 times higher than the diffraction limit of a single telescope, typically around 42.5 mm.

Once scaled for use beyond the laboratory, this device could significantly accelerate advancements in long-range, high-resolution remote sensing, surveillance, and non-invasive imaging in challenging environments.

Lu-Chuan Liu et al, Active Optical Intensity Interferometry, Physical Review Letters (2025). DOI: 10.1103/PhysRevLett.134.180201

Part 2

Comment by Dr. Krishna Kumari Challa on May 28, 2025 at 2:22pm

New high-resolution laser device reads millimeter-scale text from a mile away

According to the study published in Physical Review Letters, the developed setup includes multiple laser emitters that enable super-resolution imaging of targets as small as millimeters in scale from a 1.36 kilometers (0.85 miles) distance in an outdoor urban environment. The device successfully images letter-shaped physical targets measuring 8×9 mm, with letter widths of 1.5 mm, placed at the far end of its imaging range.

Interferometry is a widely used imaging technique in astronomy which works by merging light from different sources to create an interference pattern. These interference patterns are formed when light waves interact to either reinforce or cancel each other depending on their phase differences. These patterns carry detailed information about the object or phenomenon being studied.
Intensity interferometry, on the other hand, does not rely on combining light amplitudes or maintaining phase information but on light from a single source being measured separately by two detectors or telescopes, and the variations in their recorded intensities are compared.

Studying intensity fluctuations, correlations and their changes with the distance between the detectors can help extract spatial details about the object being studied.

What makes intensity interferometry stand out? It can cut through atmospheric turbulence and ignore flaws in telescope optics—making it ideal for long-distance, high-resolution imaging. Yet, its applications have mostly been limited to observing bright stars or objects that can be lit up with nearby light sources.

Part 1

Comment by Dr. Krishna Kumari Challa on May 27, 2025 at 12:49pm

What would we see at the speed of light?

What does the speed of light look like on earth?

Comment by Dr. Krishna Kumari Challa on May 27, 2025 at 10:20am

Environmental SOS: Rare birds crunch from bellies full of plastic

Birds on a remote Australian island are so full of plastic they crunch, British researchers report.

They found plastic in the bellies of chicks less than 3 months old and a dead bird with 778 individual pieces of plastic packed into its tummy "like a brick," according to ecologist Alex Bond, principal curator at Britain's National History Museum.

"This isn't microplastics," he told The Washington Post. "We're talking items up to and including the size of bottle caps and tetra pack lids, cutlery, clothes pegs, the takeaway soy sauce fish bottle that you get from restaurants."

A major 2023 study reported that mankind had filled the world's oceans with more than 170 trillion pieces of plastic, creating a "plastic smog" that doubles roughly every six years.

The team suspects the birds fish pieces of plastic from the ocean and feed them to their chicks, according to The Post.

Researchers combed the shores for dead birds and examined their stomach contents. They also flushed the tummies of live birds with water. In some, as much as a fifth of their total weight—up to 2 ounces—was plastic.

This is because a chemical signal emitted by the plastic causes adult birds to mistake it for food while fishing in the Tasman Sea.

The plastic in the bird  belly makes a "crunching sound" that can be heard by pressing the bird.

The bellies of some have "laminated into solid, compact bricks—likely due to their oily marine diet".

The plastic affects "nearly every organ system" of the birds, he said, especially the brain. Birds less than 6 months old exhibit signs of brain damage similar to those of dementia.

The plastic crisis is accelerating—and demanding more from all of us.

"Oh, please do something about it, the world is sending an SOS, Homo sapiens!"

Source: News Agencies

Comment by Dr. Krishna Kumari Challa on May 26, 2025 at 8:04am

Vitamin D supplements help slow telomere shortening linked to biological aging

Results from the VITAL randomized controlled trial reveal that vitamin D supplementation helps maintain telomeres, protective caps at the ends of chromosomes that shorten during aging and are linked to the development of certain diseases.

The new report, published in The American Journal of Clinical Nutrition, is based on data from a VITAL sub-study by researchers  and supports a promising role in slowing a pathway for biological aging.

VITAL is the first large-scale and long-term randomized trial to show that vitamin D supplements protect telomeres and preserve telomere length.

This is of particular interest because VITAL had also shown the benefits of vitamin D in reducing inflammation and lowering risks of selected chronic diseases of aging, such as advanced cancer and autoimmune disease.

Telomeres are made of repeating sequences of DNA, or base pairs, that prevent chromosome ends from degrading or fusing with other chromosomes. Telomere shortening is a natural part of aging and is associated with an increased risk of various age-related diseases.

A few short-term, small-scale studies have suggested that vitamin D or omega-3 fatty acid supplementation may help support telomeres, but results have been inconsistent. VITAL is a randomized, double-blind, placebo-controlled trial of vitamin D3 (2,000 IU/day) and omega-3 fatty acid (1 g/day) supplementation that tracked U.S. females aged 55 years and older and males aged 50 years and older for five years. The VITAL Telomere sub-study included 1,054 of these participants, whose telomere length in white blood cells was assessed at baseline and at Year 2 and Year 4.

Compared with taking placebo, taking vitamin D3 supplements significantly reduced telomere shortening over four years, preventing the equivalent of nearly three years of aging compared with placebo. Omega-3 fatty acid supplementation had no significant effect on telomere length throughout follow-up.

 Vitamin D3 and Marine Omega-3 Fatty Acids Supplementation and Leukocyte Telomere Length: 4-Year Findings from the VITAL Randomized Controlled Trial, American Journal of Clinical Nutrition (2025). DOI: 10.1016/j.ajcnut.2025.05.003
ajcn.nutrition.org/article/S00 … (25)00255-2/fulltext

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Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 11:40am

AI linked to boom in suspect health papers
Analysis flags hundreds of studies that seem to follow a template, reporting correlations between complex health conditions and single variables based on publicly available data sets.
A flood of papers making misleading health claims is probably the product of artificial intelligence tools scraping openly available data. In an analysis of papers that used data from the US National Health and Nutrition Examination Survey, researchers spotted over 300 papers that linked one variable, such as vitamin D levels or sleep quality, with a complex disorder, such as depression or heart disease, ignoring the fact that these conditions have many contributing factors. The papers were “extremely formulaic”, says biomedical scientist and study co-author Matt Spick, and “could easily have been generated by large language models”.

The scientific literature is at risk of becoming flooded with papers that make misleading health claims based on openly available data that are easy to process using artificial intelligence (AI) tools, researchers have warned.

In a study published in PLoS Biology recently, scientists analysed more than 300 papers that used data from the US National Health and Nutrition Examination Survey (NHANES), an open data set of health records. The papers all seemed to follow a similar template, associating one variable — for example, vitamin D levels or sleep quality — with a complex disorder such as depression or heart disease, ignoring the fact that these conditions have many contributing factors.

They  found that the associations in many of the papers did not hold up to statistical scrutiny, and that some studies seemed to have cherry-picked data.

And Youtubers and Tic-Tokers are using this data to make silly claims!

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pb...

Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 11:31am

Skin fungus keeps bacteria at bay with acid

Malassezia sympodialis — a fungus found in our skin microbiome — produces a type of fatty acid that keeps Staphylococcus aureus bacteria at bay. S. aureus is a normal resident of our skin microbiome, but it can cause dangerous infections if it isn’t kept in check. Researchers found that the fungus-produced molecule, called 10-HP, isn’t toxic to bacteria under normal lab conditions, but has antibacterial properties in a more acidic environment such as the surface of healthy skin.

https://www.cell.com/current-biology/abstract/S0960-9822(25)00371-9?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982225003719%3Fshowall%3Dtrue

Science Alert 

Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 11:23am

Skin bacteria protect us from sun damage

Some People think that the bacteria on our skin is bad. Body odor is largely caused by bacteria on your skin interacting with sweat. While sweat itself is odorless, the bacteria that live on your skin metabolize the sweat and produce the smells we perceive as body odor.

While most bacteria are harmless, some can be pathogenic and cause infections when they enter the body.

A balanced skin microbiome is important for healthy skin, and it can be disrupted by factors like harsh skincare products or environmental pollution, leading to issues like dryness, redness, or breakouts.

Bacteria on our skin could have a protective effect against a type of ultraviolet (UV) radiation in sunlight. When UV-B radiation hits our skin, it converts a molecule called trans-urocanic acid into another form: cis-urocanic acid. This form dampens the activity of immune cells in our skin’s outer layer, which can leave it more vulnerable to infections or cancer-causing mutations. Researchers found that bacteria such as Staphylococcus epidermidis in the human skin microbiome can break down cis-urocanic acid, which curbs the molecule’s immunosuppressive effects.

https://www.jidonline.org/article/S0022-202X(25)00405-1/fulltext

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