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Comment by Dr. Krishna Kumari Challa 11 hours ago

Scientists build whole-Earth simulation to help find life on other planets

A whole-Earth model simulated 5 billion years of chemical exchange among the core, mantle, crust, surface and atmosphere without life, reproducing 19 planetary properties. Adaptable to rocky exoplanets, it provides a baseline for assessing whether observed atmospheres can arise without biological activity.

Samantha Gilbert-Janizek et al., A Whole-planet Model of the Earth without Life for Terrestrial Exoplanet Studies, The Planetary Science Journal (2026). DOI: 10.3847/psj/ae9d79

Comment by Dr. Krishna Kumari Challa 11 hours ago

Collective human metabolism produces 2 billion metric tons of CO₂ a year, global study estimates

A new study has estimated that the carbon dioxide produced by humans as our bodies turn food into energy rose by 74% between 1985 and 2015, reaching 2.05 billion metric tons a year. Researchers say the findings could help scientists better understand where carbon comes from, where it goes and how human activity fits into the bigger picture.
Crucially, the CO₂ people breathe out is not the same as emissions from burning fossil fuels. The carbon we exhale comes from the food we eat and is largely carbon that plants have recently taken from the atmosphere. Fossil fuels, by contrast, release carbon that has been stored underground for millions of years.

The study found that the amount of CO₂ produced by people worldwide rose from 1.18 billion metric tons in 1985 to 2.05 billion metric tons in 2015. Population growth accounted for more than 60% of the increase.
What this study does is give us a much clearer picture of how much CO₂ people produce around the world, and how that is changing as the population grows. This understanding can help improve the accuracy of predictions of carbon reduction programs.

Javier T Gonzalez et al., Accounting for global carbon dioxide production from human metabolism between 1985 and 2015: a modelling study, The Lancet Planetary Health (2026). DOI: 10.1016/j.lanplh.2026.101546

Comment by Dr. Krishna Kumari Challa on Sunday

First patient undergoes pioneering stem-cell treatment for Parkinson's

The first patient received iPS cell-derived dopamine neuron precursors for Parkinson’s disease after conditional approval in Japan. In an earlier seven-patient trial, no major adverse effects occurred over two years, and four patients showed symptom improvement. Full approval requires confirmation of safety and efficacy.

Comment by Dr. Krishna Kumari Challa on Friday

Is it a boy or a girl? For alligators, it may come down to one degree

The future of the alligator species could come down to a one- or two-degree temperature difference, according to new research .
A small change on the thermometer could determine whether a gator develops as a male or female. And that could have ramifications for alligator populations as temperatures rise.

Typically, incubations at cooler temperatures (think 86 to 88 degrees Fahrenheit) and hot spells (97 degrees Fahrenheit and above) result in more female gators. Moderate temperatures (90 to 92 degrees Fahrenheit) yield more males.

But these trends largely reflect controlled experiments in laboratories in which alligator eggs are incubated under constant temperatures.

Nests in the wild don't experience constant temperatures; instead, temperatures fluctuate due to heat waves or just going from day to night.

The present study gives scientists a better understanding of real-world nest conditions.
Whenever a population is out of balance, it can impact population growth. Whenever you start to lose females, then the population can really get in trouble.
The researchers' new model closely matched previous sex outcomes at cooler temperatures. But at higher temperatures, even a change of one or two degrees made a big difference in whether alligator embryos developed as male or female.
A small difference can lead to mostly males or mostly females being produced.
That's really relevant for how the environment is going to be changing in the near future. If temperatures are biasing sex ratios, that's a big issue.
The eggs' swap back to a female outcome occurred at a lower temperature threshold than anticipated. Whereas some previous models expected the flip to happen around 97 degrees Fahrenheit, the new model suggests that sex was more likely to be female starting at 93 degrees Fahrenheit. Temperatures between the two female-producing ranges still produce mostly males.

Karin R. Ebey et al., A sex ratio by incubation temperature reaction norm for the American alligator ( Alligator mississippiensis ) based on fluctuating thermal regimes, Journal of Experimental Biology (2026). DOI: 10.1242/jeb.252972

Comment by Dr. Krishna Kumari Challa on Friday

Microplastic shape can influence viral disease severity in rainbow trout
Continuous nylon microfiber exposure approximately doubled the odds of death in rainbow trout infected with infectious hematopoietic necrosis virus, while rounded nylon particles did not significantly increase mortality. These laboratory results indicate that microplastic shape can affect viral disease severity; effects in natural environments remain uncertain.

Meredith E Seeley et al., Microplastic fibers can alter viral disease severity, contingent on particle shape and exposure timing, Environmental Toxicology and Chemistry (2026). DOI: 10.1093/etojnl/vgag233

Comment by Dr. Krishna Kumari Challa on Friday

Because internal clocks regulate many aspects of animal behaviour and physiology, the researchers suggest that similar time shifts could potentially have effects beyond navigation. In humans, traveling rapidly across time zones can cause jet lag, which involves a mismatch between the body's internal clock and local time and can lead to disturbed sleep, fatigue and other symptoms.

Patrick Lewin et al., Rapid longitudinal flights cause time shifts and sun compass error, Science (2026). DOI: 10.1126/science.adz2542. www.science.org/doi/10.1126/science.adz2542

Part 2

Comment by Dr. Krishna Kumari Challa on Friday

Long-distance flights can throw seabirds' internal clocks out of sync, causing navigation errors
A new study has found that seabirds flying long distances across the Atlantic can experience a mismatch between their internal body clocks and local time (the same process that leads to jet lag in humans), causing them to make predictable errors when navigating by the sun. The results have been published in the journal Science.
Many animals, including birds, use the sun to find their way. But because the sun moves across the sky throughout the day, they need an accurate internal clock to interpret its position correctly.

Normally, birds reset their internal clocks using sunrise as a cue. However, when they travel rapidly east or west during the day, their internal clocks may temporarily become out of sync with local solar time. This could cause them to misjudge the sun's position and fly slightly off course.

To investigate whether this happens in the wild, researchers analyzed 20 years of GPS tracking data from 1,045 Manx shearwaters, covering 3,688 foraging trips.
Manx shearwaters (Puffinus puffinus) breed on islands off the western coasts of the U.K. and Ireland. They regularly travel hundreds of kilometers out to sea in search of food, sometimes reaching feeding grounds around 1,000 km (621 miles) west of their breeding colonies.

When returning to their nests, the birds can travel rapidly eastward across lines of longitude, moving into places where the sun rose earlier (just as we do when we fly into earlier time zones). As a result, their internal clocks may lag behind local solar time by up to around one hour.

The researchers found that the birds' flight directions showed systematic deviations consistent with the predicted effects of these time shifts on their sun compass. As the birds traveled eastward, they tended to deviate clockwise from their expected direction, as would be predicted if their internal clocks were running behind local time.

The team used statistical models to compare the observed deviations with those predicted from the birds' movements and the changing position of the sun. The results supported the sun-compass explanation, which also fit the data better than an alternative explanation based on changes in the Earth's magnetic field.
The researchers found that these navigational errors persisted even when the birds were flying along visible coastlines, where landmarks could help guide them. When the predicted compass error pointed toward land, the shearwaters tended to fly closer to the coast. When it pointed away from land, they tended to fly farther out to sea.

This suggests that the birds continued to rely on their sun compass even when other navigational cues were available, rather than simply following the coastline.
So billions of migratory animals look up to the sun for direction, relying on clocks silently ticking away inside them, and that errors in those clocks can cause them to take tiny shifts off course.

The navigational errors were relatively small, reaching approximately 15° in the shearwaters studied. Because these birds appear able to reassess their position and adjust their route home continuously, the additional distance travelled is likely to be modest.
However, the findings could have wider implications for animals that travel long distances without being able to correct their position continuously. For example, in birds undertaking their first migration, small compass errors could potentially accumulate, shifting their eventual destination by hundreds of kilometers.

Part 1

Comment by Dr. Krishna Kumari Challa on Thursday

Night shifts during pregnancy linked to heightened risk of young child's neurodevelopmental abnormalities
Working night shifts during pregnancy is linked to a heightened risk of neurodevelopmental abnormalities detected by screening in the child by the age of 4, finds research published online in Occupational & Environmental Medicine.
But nightly prenatal sleep length during this period may modify this observed association, exploratory findings suggest.

Night shift work during pregnancy has been associated with unfavourable health outcomes for both mother and child, including neurodevelopmental issues, potentially related to body clock and sleep disturbances, note the researchers.
During the study researchers noted that compared with the children of mothers who didn't work night shifts, the children of those who discontinued night shift work were more likely to have developmental screening abnormalities, but only in the fine motor skills domain (24% higher risk).

But the children of mothers who continued night shifts during their pregnancy had higher risks of developmental abnormalities in three domains compared with children whose mothers didn't work night shifts.

These were in the domains of communication skills (29% higher risk); fine motor skills (34% higher risk); and personal–social functioning (31% higher risk).

Only the fine motor skills domain showed a significant association, regardless of whether night shifts were continued or discontinued.

"One possible explanation is that maternal inflammation associated with persistent night work may preferentially affect neural pathways involved in fine motor function," suggest the researchers.

A separate exploratory analysis showed that the observed association between night shift pattern and the child's neurodevelopmental risk differed according to how long the mothers slept.

Prenatal sleep duration of 10 or more hours was associated with an 80% heightened risk of abnormalities in any of the five domains compared with prenatal sleep length of 6–9 hours.

Long prenatal sleep duration may also reflect underlying fatigue, subclinical depression, inflammation, or anemia, rather than representing a harmful exposure in itself, suggest the researchers.
In light of the findings, it may be worth employers considering flexible work schedules for pregnant night shift workers, they say.

Maternal night shift patterns during pregnancy and offspring's development at 4 years of age: the Japan Environment and Children's Study, Occupational and Environmental Medicine (2026). DOI: 10.1136/oemed-2026-111018

Comment by Dr. Krishna Kumari Challa on Thursday

Comets probably didn't seed life on Earth after all, new study suggests
The theory that comets delivered the molecular building blocks for life on Earth is a long-standing one, since comets are known to carry many of these molecules. However, a new study challenges this idea.

Researchers found the cometary delivery of these building blocks would be—at best—a 'one-off fluke,' and not the steady rain of prebiotic molecules that had been theorized.

Using computer modelling, the researchers determined that comets travel too fast and at too sharp an angle to Earth's atmosphere for the fragile organic molecules to survive: they would almost certainly vaporize on impact with the surface. However, the researchers also found that another planet in our system—Mars—could be a slightly more promising candidate for cometary delivery of prebiotic molecules, although this is still highly unlikely. The results are published in the journal Scientific Reports.

Cometary impacts an unlikely pathway towards the origins of life on Earth, Scientific Reports (2026). DOI: 10.1038/s41598-026-74214-y

Comment by Dr. Krishna Kumari Challa on October 28, 2026 at 11:28am

Scientists reveal hidden world of living cells in human milk

Human milk is a complex biological system containing many different types of living cells.

Advanced nanoscale imaging technology has revealed the diversity of living cells in human milk and uncovered new insights into how these cells are structured, what they contain and how they use nutrients.
Researchers examined major cell populations found in human milk, including milk-producing cells, known as lactocytes, and different types of immune cells such as neutrophils, macrophages and dendritic cells.
Nanoscale imaging, isotope tracing and single-cell analysis identified distinct metabolic profiles in human milk cells. Macrophages incorporated glucose into lipid droplets, lactocytes showed active protein production and energy metabolism, and neutrophils contained high sulfur and iron levels.

Qiongxiang Lin et al., Multimodal Nanoscale Imaging Reveals Cellular and Metabolic Complexity of Human Breast Milk, ACS Nano (2026). DOI: 10.1021/acsnano.6c12691

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