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Comment by Dr. Krishna Kumari Challa on September 19, 2026 at 10:19am

SMA is a leading genetic cause of death in children under 1 year of age. ALS, which is often diagnosed between the ages of 40–70, affects both the forebrain and the hindbrain. In both disorders, certain hindbrain neurons gradually cease to function, and the patient loses the ability to swallow, which can cause pneumonia when food or liquid is inhaled into the lungs. Eventually, patients lose the ability to breathe.

The researchers' breakthrough came from studying the earliest moments of embryonic development, during a stage called gastrulation, when the body first takes shape.
Researchers discovered that the hindbrain follows a separate developmental path, running in parallel to—rather than branching off from—the pathway that creates the forebrain and midbrain.
The researchers learned this by examining developing mouse embryos. They identified two different brain progenitor cells. One, which expresses a gene called Otx2, is destined to become the forebrain and midbrain. The other, which expresses a gene called Gbx2, is committed to forming the hindbrain. They showed that these two cell populations never overlap; they are mutually exclusive from the earliest stages of development.

The team then examined the DNA packaging, or chromatin, in these cells. Chromatin is a way cells determine which genes can be easily accessed and which are bundled away out of reach. What they found was striking: The anterior neural ectoderm (future forebrain and midbrain) and posterior neural ectoderm (future hindbrain) have fundamentally different chromatin configurations. These differences essentially locked each progenitor cell into its respective fate, like travellers on parallel tracks that never cross.

Previous attempts to make hindbrain neurons likely tried to coax forebrain and midbrain progenitors into hindbrain cells, which this study shows is not possible.
This revelation explained decades of frustration in the field—scientists had been trying to turn one type of progenitor cell into another that it is fundamentally incapable of becoming.
Armed with this knowledge, the researchers for the first time successfully coaxed human pluripotent stem cells (a kind of cell that can create any cell in the human body) to become functional hindbrain motor neurons in the laboratory. These lab-grown neurons displayed all the hallmarks of authentic hindbrain cells: They exhibited waves of electrical activity called action potentials and made proteins that identify the segments of the hindbrain that control facial and swallowing muscles.

Finally, the researchers looked back over 550 million years of evolutionary time. They found the same two-origin brain pattern in chickens, zebrafish and, remarkably, acorn worms, tiny creatures living on the ocean floor that share a distant common ancestor with humans. Jellyfish, which diverged from humans about 600–700 million years ago, have two nervous systems at different ends of their bodies.

This research suggests that evolution took two existing neural systems and pushed them together spatially.
This is interesting the word 'brain' implies a contiguous organ that likely has a singular origin. But even 500 million years ago, there were these separate neural systems, which now almost operate as one, which is very cool.

Two parallel neural ectoderm progenitors contribute to the developing brain, Nature Neuroscience (2026). DOI: 10.1038/s41593-026-02433-7

Part 2

Comment by Dr. Krishna Kumari Challa on September 19, 2026 at 10:14am

Human brain has a split origin, new research suggests

For centuries, scientists have thought of the brain as a single, unified organ. But new research reveals that what we call the brain is two distinct organs that evolved independently over hundreds of millions of years.
The discovery overturns a prevailing model of brain development. For decades, researchers have subscribed to the theory that a single progenitor cell early in development gives rise to the entire brain. This model suggested all parts of the brain shared a common developmental origin.

The new findings show that the human brain consists of two ancient nervous systems packaged together—a more primitive part that regulates our hearts' beating, breathing and other functions, and another that makes us distinctly human, capable of poetry, mathematics and wondering about our own origins.

The discovery could help explain why scientists have struggled for decades to grow certain types of brain cells in the laboratory—and it opens new avenues for studying devastating diseases that affect the brain stem, such as spinal muscular atrophy (also known as SMA) and amyotrophic lateral sclerosis (also known as ALS or Lou Gehrig's disease).
Scientists have shown for the first time that the front of the brain arises from a totally different progenitor cell than the back of the brain. This discovery means that we can now grow neurons from the back of the brain, the hindbrain, in a Petri dish and study their functions.
The adult brain has three main regions: the forebrain, midbrain and hindbrain. The forebrain handles higher-level thinking—language, consciousness and abstract reasoning. In contrast, the hindbrain, located at the back of the skull and often called the brain stem, controls essential, automatic functions that keep us alive: breathing, sleeping and regulating our heartbeat and hunger urges. Hindbrain neurons also control the muscles of the face, tongue and throat, which affect speech and swallowing.

Despite the critical importance of the hindbrain, scientists have struggled for decades to generate human hindbrain neurons in the laboratory. This gap has hampered research into devastating diseases affecting the brain stem, including spinal muscular atrophy and amyotrophic lateral sclerosis.
Part 1

Comment by Dr. Krishna Kumari Challa on September 19, 2026 at 8:26am

Listening to a forest before it changes forever 

In this episode, filmmaker and journalist Leah Varjacques takes us to a Bornean rainforest area, where centuries-old patterns of human and wildlife behavior are being disrupted by the construction of a new capital city. In the midst of all this change, Varjacques documents the work of Wendy Erb, a primatologist and bioacoustic scientist at the Cornell Lab of Ornithology. Erb’s team, working with members of the local Balik population, placed audio recorders around the forest to capture the sounds of this diverse ecosystem before it changes forever.

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 12:56pm

Scientists Discover Strange 4-Stranded Genetic Structures in Human Blood

If you think you know what DNA looks like, there may be a surprise hiding in your blood.

DNA instantly brings to mind its famous double helix. But genetic material does not always remain in that familiar form. Some pieces can fold into compact, four-stranded structures.

These unusual shapes have previously been seen inside cells. Now scientists say they have caught them folded in human blood plasma.

So why is DNA in our blood at all?

As cells throughout the body die, they leave behind small fragments of DNA. These enter the bloodstream like pieces of a torn message, carrying clues about what is happening inside us.
Until now, scientists have concentrated on reading the message: its genetic letters, the length of each fragment, and where in the genome it came from. A new preprint study suggests that how the message is folded could matter too.

Researchers detected four-stranded structures called G-quadruplexes, or G4s, in genetic material captured directly from human plasma.

A G4 begins when four copies of the genetic letter guanine join to form a tiny square. Several squares can stack together, creating a compact structure very different from the familiar double helix.

The mystery began when scientists noticed unusual fragments known as ultrashort cell-free DNA. At roughly 50 genetic letters long, these single strands were so small that they could slip through the nets used by standard DNA-capturing methods.
Some contained enough guanine to form G4s, and computer analyses pointed to the same possibility.

But finding a piece of string that could form a knot is not the same as finding it already knotted. The team had to catch these structures in human blood while they were still folded.
The discovery opened another mystery.

Although the investigation began with ultrashort DNA, the experiment could not reveal whether the detected G4s were made from DNA or RNA. RNA can fold into the same four-stranded shape, and the detectors recognize the structure rather than the molecule underneath it.
Scientists also do not yet know which tissues released them, or whether the structures folded inside cells or only after entering the bloodstream.
G4s often occur in parts of the genome involved in controlling genes, and elevated G4 levels have been observed in several tumor types. This raises the possibility that G4s circulating in blood could one day provide information about cancer that cannot be found by reading DNA sequences alone.

https://www.biorxiv.org/content/10.64898/2026.09.05.747829v1

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 12:46pm

Scientists Gave People BPA For 5 Days. Their Insulin Sensitivity Changed

A ubiquitous industrial chemical commonly used in food and beverage packaging may quietly mess with the body's insulin sensitivity when ingested.

Bisphenol A (BPA) is one of the highest-volume chemicals produced worldwide.

Since the 1960s, it has been used to manufacture an unfathomable number of plastic packages and epoxy resins, which coat the insides of many food and beverage cans.

By some estimates, BPA is so widely consumed that it is present in the urine of more than 90 percent of the US population.

But is that safe?

US health guidelines might say yes, but the first experimental evidence in humans has now found that ingesting BPA, even at low doses, may reduce insulin sensitivity in the short term.
Reducing BPA exposure, such as using stainless steel or glass bottles and BPA-free cans, may lower diabetes risk.

https://academic.oup.com/jcem/article/111/9/2610/8537216?login=false

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 12:01pm

Driving through water is the biggest cause of death during floods—here's how it can happen
Driving through floodwater can cause vehicles to float, be swept downstream and overturn, creating a drowning risk. In a survey of 185 drivers, most recognized unsafe water depths but underestimated the danger of moving water. Dynamic LED flood warnings attracted more attention and were judged more effective than static signs.

Matthew Watkins et al, An investigation into driver's perceptions of road flooding and adherence to signage, Transportation Research Part F: Traffic Psychology and Behaviour (2026). DOI: 10.1016/j.trf.2026.103639

original article.

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 11:10am

Advertising is coming to AI chatbots—and it could influence the answers you get
Embedding targeted advertising within AI conversations could blur sponsored and organic information, enabling commercial influence over answers and transactions. Personalized, ephemeral chats may amplify misinformation while evading fact-checking and existing regulation. Clear safeguards are needed to prevent sponsors from shaping AI-generated content beyond disclosure labels.

Carlos Diaz Ruiz et al, Advertising in AI Models: How the Zero-Click Internet Threatens Free Markets and Free Speech, Journal of Public Policy & Marketing (2026). DOI: 10.1177/07439156261436399

original article.

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 10:55am

Climate change made deadly Nepal glacier and rock collapse more likely, according to analysis
Human-caused warming likely increased instability of the Nepal Himalayan slope by accelerating glacier thinning, retreat, permafrost thaw, and higher freezing elevations. The Aug. 26 collapse, which killed over 1,300 people, may also have been influenced by earthquake-related rock weakening. Rapid failures can exceed warning-system capacity.

This disaster was not an extreme weather event, but the fingerprints of climate change are still clear to see in long-term changes, say the experts.

Climate scientists say that across the Himalayas rising temperatures are causing glaciers to retreat and thawing permanently frozen ground that helps bind fractured mountain rock together. That means climate change can alter not only weather hazards such as heat and heavy rain, but the stability of the mountains themselves—threatening communities concentrated in narrow river valleys below.
The report by the World Weather Attribution
**

Comment by Dr. Krishna Kumari Challa on September 18, 2026 at 10:30am

Earth's atmosphere is getting less dusty: That could be adding to global warming

Atmospheric desert dust has long swirled around the globe, but a new study presents the strongest evidence yet that global dust is mysteriously decreasing. Because atmospheric dust has a slight overall cooling effect on the climate, the researchers say its decrease may have contributed modestly to recent climate warming.

Atmospheric dust declined about 10% from 2003–2023, reversing much of the 20th-century increase. Because dust exerts a small net cooling effect, its reduction likely contributed modestly to recent warming. Causes remain unclear; dust changes also affect nutrient deposition, air quality, and snow and ice reflectivity.
The study, which combined satellite observations, ground-based measurements and atmospheric models, found that the amount of dust in Earth's atmosphere decreased by about 10% from 2003 to 2023.

Most atmospheric dust originates in the Northern Hemisphere, with major desert regions such as the Sahara in North Africa and the deserts of Asia, including the Gobi, contributing much of the global dust burden.

The causes of the recent decline, however, remain unclear, according to the study, published in Science Advances.

Ashok Kumar Gupta et al, A global decline in atmospheric dust during the 21st century, Science Advances (2026). DOI: 10.1126/sciadv.aef5691

Comment by Dr. Krishna Kumari Challa on September 17, 2026 at 7:38am

'Momnesia' is real—scientists find a biological explanation for temporary forgetfulness during pregnancy

Many women say the same thing during pregnancy: They walk into a room and forget why, misplace their keys or struggle to follow a conversation. This phenomenon, often called "pregnancy brain" or "momnesia," has long lacked a clear biological explanation.
Now, a new study by researchers at Baylor College of Medicine and collaborating institutions, published in Science Bulletin, identifies a specific brain circuit in an animal model that becomes disrupted under the sustained high estrogen levels present during pregnancy. The findings offer the first biological explanation of how exposure to high levels of circulating estrogen can temporarily impair memory.
The new findings suggest a possible explanation—it may not simply be a matter of "more estrogen is better" or "worse," but rather where in the brain estrogen acts and at what levels.

"Low-level, cyclical estrogen exposure appears to support cognitive function, which is part of why hormone therapy can help postmenopausal women.
But sustained, high-level estrogen exposure seems to engage a different pathway altogether, one centered in the hypothalamus rather than the hippocampus itself. That distinction may help reconcile a lot of conflicting data in the field.
Sustained high estrogen impaired task-specific memory in mice by reducing estrogen receptor-α signaling in lateral hypothalamic GABAergic neurons, increasing activity in a hypothalamus–hippocampus circuit. Silencing this pathway prevented impairment. In pregnant women, late-pregnancy memory deficits correlated with estrogen levels and appeared temporary.
To determine whether these findings translate to humans, the researchers assessed memory performance in women across different stages of pregnancy. They found task-specific memory impairments that emerged during late pregnancy and correlated with circulating estrogen levels, even after accounting for other factors that might influence cognition. These human data support the idea that the hormone-driven circuit identified in mice may underlie the memory changes many pregnant women experience.
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Momnesia is real, it has a defined biological basis and is temporary. The memory changes observed in both mice and women were temporary and task-specific, not a sign of broader cognitive decline.

Xin Li et al, High-level estrogen impairs memory via estrogen receptor signaling in a hypothalamic–hippocampal neural circuit, Science Bulletin (2026). DOI: 10.1016/j.scib.2026.08.057

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