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Comment by Dr. Krishna Kumari Challa on Wednesday

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 Tuesday

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 Tuesday

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

Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 11:04am

A soil predator’s death is boosting drug resistance, without antibiotics

Research reveals how the natural demise of Myxococcus xanthus helps antibiotic-resistant bacteria thrive

Researchers at the Indian Institute of Science studying microbial interactions in soil have stumbled on an ecological twist: the death of a bacteria hunter was helping drug-resistant bacteria flourish.

At the centre of it was Myxococcus xanthus, a predatory slime bacterium known for its pack-hunting prowess. In soil across the world, M. xanthus swarms its microbial prey and kills en masse. But when researchers introduced it into soil samples and let it die off, they found that in the absence of antibiotics, bacteria resistant to drugs like tetracycline and rifampicin multiplied rapidly.

The researchers  kept seeing the same result over and over again. 

Repeated experiments confirmed it: the breakdown of M. xanthus cells — a process called lysis — during fruiting body formation, released a cocktail of biomolecules, including proteins and phosphodiester compounds.

The findings challenge the dominant narrative that antimicrobial resistance in the environment is mainly driven by pollution from sewage, pharmaceutical waste, or agriculture. Instead, the team shows that natural ecological dynamics, like bacterial predation and death, can promote resistance without human interference.

Chemical analysis confirmed the presence of growth-inhibiting substances in the lysed bacterial mix — the same substances that M. xanthus once used to kill its prey. The phenomenon seems to offer resistant strains a survival edge. “It’s almost like the predator clears the competition before dying, so its spores, — and other resistant organisms, — face less of a fight.

https://www.cell.com/current-biology/abstract/S0960-9822(25)00131-9?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982225001319%3Fshowall%3Dtrue

Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 10:12am

Microplastics are 'silently spreading from soil to salad to humans'

According to a new  review work agricultural soils now hold around 23 times more microplastics than oceans. Among the revelations in the comprehensive evaluation is that plastics in soil may be exposed to up to 10,000 chemical additives, most of which are unregulated in agriculture.

These microplastics are turning food-producing land into a plastic sink.

Both microplastics and nanoplastics have now been found in lettuce, wheat and carrot crops. This happens through various means, from plastic mulching, fertilizers and even through being dropped by clouds.

This is particularly concerning when combined with findings of these plastics in the human lungs, brain, heart, blood, and even placenta.

And BPA-free does not equal risk-free. Replacement chemicals like BPF and BPS show comparable or greater endocrine-disrupting activity. 

The challenge is that regulations are slower than science, and industry is faster than both.

In addition to this, assessing additive toxicity is often overlooked  due to the lack of transparency in the plastic industry and the large number of additives produced.

 This makes the plastic crisis unchecked, and human health exposed.

Alongside endocrine disruptors, the review pinpointed other additives in soil such as phthalates (linked to reproductive issues), and PBDEs (neurotoxic flame retardants).

These additives have been linked with neurodegenerative disease, increased risks of stroke and heart attack and early death.

These are not distant possibilities—they are unfolding within biological systems—silently and systematically, say the reviewers. 

This review highlights the urgent need for coordinated scientific and regulatory efforts.

 Joseph Boctor et al, Microplastics and nanoplastics: fate, transport, and governance from agricultural soil to food webs and humans, Environmental Sciences Europe (2025). DOI: 10.1186/s12302-025-01104-x

Comment by Dr. Krishna Kumari Challa on May 23, 2025 at 10:01am

Ammonia made from air, water and sunlight: Catalysts mimic photosynthesis for cleaner production

Ammonia is a chemical essential to many agricultural and industrial processes, but its mode of production comes with an incredibly high energy cost. Various attempts have, and are, being made to produce ammonia more efficiently.

For the first time, a group including researchers from the University of Tokyo combined atmospheric nitrogen, water and sunlight, and, using two catalysts, produced sizable quantities of ammonia without a high energy cost. Their processes mirror natural processes found in plants utilizing symbiotic bacteria.

The work has been published in Nature Communications

They succeeded in developing a novel catalytic system for producing ammonia from abundant molecules found on Earth, including atmospheric nitrogen and water. The key lies in a combination of two kinds of catalysts, intermediate compounds which enable or speed up reactions without contributing to the final mixture, made especially for ammonia production, and which are driven by sunlight.

Yasuomi Yamazaki et al, Catalytic ammonia formation from dinitrogen, water, and visible light energy, Nature Communications (2025). DOI: 10.1038/s41467-025-59727-w

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