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Comment by Dr. Krishna Kumari Challa 5 hours ago

Older brains work harder to stay upright, with nearly 50% longer delay

Aging is known to degrade sensory systems, posing a major challenge to balance control and resulting in an increased risk of falls.
Researchers  have shed light on the brain mechanisms underlying age-related changes in postural control. Using a novel approach, the researchers discovered that older brains must work significantly harder than younger ones to process sensory information and control movement, alongside a substantial processing delay.

Older adults exhibit significantly increased brain activity and nearly 50% longer processing delays when maintaining balance compared to younger individuals. This heightened neural effort is closely linked to greater postural instability and is not solely explained by vestibular decline, indicating that aging brains require more active control to maintain upright posture.

The study demonstrated that when older adults try to stay balanced, their brain activity syncs up closely with how much they wobble, especially in difficult balancing situations—and those who wobble the most have the highest brain activity.
This means that older adults have to actively maintain their balance, using parts of their brain to stay upright. Younger people, on the other hand, stay balanced automatically without having to think about it or use up mental energy.

Furthermore, it takes significantly longer for an older person's brain to process balance information, almost 50% longer. Interestingly, even though many older participants showed inner-ear decline, this wasn't the reason their brains were working so much harder.

Ultimately, this research helps us understand how the aging brain controls balance, and it opens the door for future studies in medicine and neuroscience to help predict and hopefully prevent fall risks in older adults.

Thomas Legrand et al, Aging increases the cortical resources allocated to static balance maintenance, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2524894123

Comment by Dr. Krishna Kumari Challa 5 hours ago

Ebola may have spread beyond Africa. How are health authorities responding?
The current Ebola outbreak, caused by the Bundibugyo strain, has resulted in over 900 suspected cases and 223 deaths in the DRC, with limited spread to Uganda and suspected but unconfirmed cases in Italy and Brazil. International health authorities have declared a public health emergency, implemented travel restrictions, and activated safety protocols. Vaccine development is being accelerated, but the risk of global spread remains low with current containment measures.

Similar to the West African outbreak, this latest Ebola outbreak has spread to other continents through travel.

Nine cases and one death have already been reported in Uganda, which shares a border with the DRC.

An American man who tested positive for Ebola while working in the DRC, is in a stable condition after being treated in Germany.

In Italy, authorities are monitoring a traveler who recently returned from the DRC to the city of Cagliari.

According to some reports, Brazilian authorities are investigating two suspected Ebola cases. They are believed to be two travelers, one who returned from the DRC to São Paulo and the other from Uganda to Rio de Janeiro.

Importantly, both suspected cases have been diagnosed with other illnesses. The São Paulo patient presented with fever and was later diagnosed with severe meningitis. The Rio de Janeiro patient tested positive for malaria after developing a cough, chills and diarrhea, but has since tested negative for Ebola.

So for now, no Ebola cases have been confirmed in Brazil. But these suspected cases have prompted the country to activate its Ebola safety protocols, including patient isolation, laboratory testing, and epidemiological investigations.

Meanwhile, several countries have imposed travel restrictions to prevent Ebola from reaching their shores.

original article.

Comment by Dr. Krishna Kumari Challa 5 hours ago

These sounds have long wavelengths that can travel over great distances.

The first thing the researchers did was test whether the participants had particularly good hearing for low-frequency sounds that are actually known to exist.

Most did not, except for two participants who had better hearing than average at certain low frequencies.
It still means that the hypothesis of having especially good hearing for low-frequency sounds does not hold for most people.
There are differences in hearing thresholds (microstructures) that make it possible for some people to hear sensitively in a very narrow frequency range, for example between 50 and 51 Hertz. These nuances are not captured by conventional hearing tests.
The ear can produce sounds itself
The cochlea in the inner ear itself produces weak sounds with different frequencies, typically between about 500 and 5000 Hertz. These sounds have no function of their own, but are a by-product of a physiological sound amplification process.

Most of us don't hear these sounds. However, a few people can actually hear the sounds that the ear itself produces. And these sounds can be measured objectively
These particular sounds are called oto-acoustic emissions and can be detected by placing a sensitive microphone in the ear canal. In some people, these spontaneous oto-acoustic emissions can be experienced as troublesome tinnitus.

"One hypothesis was that the participants in our group could hear oto-acoustic emissions at low frequencies.
But… the answer was no.
Sounds that cannot be measured
"Then there are people who hear something that cannot be measured objectively.
Tinnitus or ringing in the ears is when you hear a sound in the ear or in the head, which is not caused by an external sound source.

Many people experience tinnitus, either permanently or for shorter periods. These individuals first experience the sounds in their ears as a sound coming from outside.

But as the sound persists, even when they move to other places, they gradually become aware that the source of the sound is not external.
based on what is known about hearing and the tests they conducted on study participants, the best explanation is twofold.

A few people who hear the hum actually have particularly good low-frequency hearing. However, for most people, it may be a form of tinnitus, meaning a sound that originates from inside the auditory system.
Based on the results, although the researchers haven't ruled out cases of physical external sound sources, they suggest that subjective tinnitus in the low-frequency range is often the cause of hearing pulsations of low-frequency sound perceptions.

Bonifaz Baumann et al, On the potential sources of a low-frequency sound percept that only a few can perceive, PLOS One (2026). DOI: 10.1371/journal.pone.0326818

Part 3

Comment by Dr. Krishna Kumari Challa 5 hours ago

Many different theories have been offered to explain the cause of the phenomenon; everything from acoustic pollution from human-made sources to sounds that nature itself makes—as well as conspiracy theories that the sound is produced by the CIA or even aliens.

There are many human sources of low-frequency sound. These can include ventilation systems, heat pumps, traffic noise, windmills and more. Examples of natural sources include the sounds of waves crashing along the coast and wind sweeping through the landscape.

The hum has attracted the interest of hearing and audiology researchers worldwide.
Other explanations for 'the hum'
Military aircraft and submarines
One theory that has been proposed is that the hum relates to sound waves from US military aircraft that use radio frequencies at the lowest end of the spectrum of sound frequencies to communicate with submarines. These aircraft operate at night, and their movements are top secret. The theory may also explain why many "hum sites" are located on the coast.

Amorous fish
The Scottish Association for Marine Science has suggested that the noise in the UK coastal town of Hythe could be caused by the mating call of schools of male plainfin midshipman fish (Porichthys notatus). Amorous male fish make loud sounds, sometimes for hours, to attract females.

Waves, volcanic eruptions, or lightning strikes
In 2015, French researchers suggested that the hum was caused by waves moving along the seafloor. When the waves collide with ridges on the continental shelves, it creates vibrations that are audible to some.

Other researchers have suggested that vibrations caused by volcanic eruptions and earthquakes could be the cause.

Yet another theory points to the lightning strikes that strike Earth every day. Lightning strikes build up a massive electromagnetic charge that creates a resonance between Earth's surface and the ionosphere—much like blowing air over the top of a bottle.

Sensitive brains
Dr. David Baguley, head of the audiology department at Addenbrooke's Hospital in England, has done extensive research into the phenomenon. He believes it is due to sensitive brains that can pick up ultra-low sound frequencies.

He pointed out that our sense of hearing is greatly affected if we experience a lot of stress, and the brain turns up the volume to detect threatening sounds.

Sounds that can be measured
The researchers tested two hypotheses.

One was that the hum can be measured, both from human-made infrastructure and industry and also from nature itself, which creates low-frequency sounds.

Part 2

Comment by Dr. Krishna Kumari Challa 6 hours ago

The hum that only a few can perceive: Potential sources of a low-frequency sound

Some people occasionally hear a low buzzing or humming sound that doesn't have a clear source. An estimated 2–4% of the world's population hear this. Scientists have been trying to figure out for decades where this sound comes from.

Some people find the sound annoying but can live with it. Others can get sick from this low-frequency sound, which is often also experienced as a vibration.

The humming sound isn't easy to hear outdoors, but it often appears indoors—and is most noticeable when you've gone to sleep at night. If you look out the window to see if there is something with a motor in the neighborhood, there's nothing to see.

And others who are in the same place hear nothing.
The hum phenomenon, a persistent low-frequency sound perceived by 2–4% of people, has unclear origins and is reported globally, often in densely populated or coastal areas. Potential sources include human-made infrastructure, natural phenomena, and individual auditory sensitivity, but most cases are not linked to especially acute low-frequency hearing or measurable oto-acoustic emissions. Evidence suggests that for most individuals, the hum is a form of low-frequency tinnitus, while a minority may detect actual external sounds. Improved understanding of low-frequency auditory processing is needed to clarify the phenomenon’s mechanisms.
The phenomenon was first recorded and discussed in the city of Bristol, England in the mid-1970s. Suddenly, the Bristol Evening Post began receiving letter after letters from people who heard an inexplicable sound, and wondered where it came from.

One theory was that the humming sound came from large, industrial fans that were located inside the warehouse of a large department store. However, when the warehouse was closed down a few years later, people continued to hear the sound.

Since then, the sound has been recorded in several places in the United Kingdom, mainly in coastal cities such as Hythe, Plymouth, Southampton, Swansea, but also in London.

The sound is called the hum phenomenon, or simply the hum.
In the 1990s, it cropped up in the United States, first in the city of Taos, New Mexico and in the city of Kokomo, Indiana. The phenomenon has since been recorded worldwide: in Canada, Australia, New Zealand, South Africa and several European cities. The sound is typically reported in relatively densely populated areas.

A couple of years ago, people in the Oslo area also reported an unexplained humming sound, according to the Norwegian Broadcasting Corporation (NRK).
Part 1

Comment by Dr. Krishna Kumari Challa 6 hours ago

Single cell transforms into cannibalistic 'supergiant,' swallowing its clones whole

Researchers have discovered a microscopic organism that can transform into a cannibalistic "supergiant" that drastically changes size, shape, and behavior, and abandons filter-feeding to hunt and consume their genetically identical relatives.
Euplotes gigatrox, a newly identified ciliate, can transform from a filter-feeding cell into a larger, cannibalistic "supergiant" that preys on its clonal relatives. This transformation represents a distinct, transcriptionally regulated developmental stage, with altered morphology, behavior, and gene expression. Supergiant formation is rare, environmentally triggered, and may represent a bet-hedging strategy.
The work demonstrates how single-celled organisms are capable of complex, regulated development, which scientists have largely only studied in multicellular animals.
In clonal populations of these organisms where every cell shares the same DNA, a small number of cells can spontaneously develop into supergiants more than twice the length of normal cells, with a broader body shape and a larger mouth.

Rather than filter-feeding on bacteria as normal cells do, supergiants become raptorial predators, running over smaller clonal relatives to capture and swallow them whole at a rate of roughly one prey every 10 minutes.

Ben T. Larson et al, Regulated development of cannibalistic supergiant cells in the ciliate Euplotes gigatrox, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2606891123. On bioRxiv: www.biorxiv.org/content/10.110 … /2025.08.19.671124v2

Comment by Dr. Krishna Kumari Challa 6 hours ago

A small amount of rare earth metal shapes the environmental impact of magnets
Dysprosium, though comprising only 1–8% of permanent magnets used in electric vehicles and wind turbines, accounts for up to 78% of their environmental impact and 44% of raw material costs due to energy- and chemical-intensive extraction and separation processes. Reducing dysprosium content through improved material efficiency or alternative technologies could significantly lower environmental and economic burdens while decreasing supply chain vulnerability.

Stellina Samuel et al, Mitigating the disproportionate environmental impacts and costs of dysprosium in Nd-Fe-B magnets through material efficiency, Sustainable Production and Consumption (2026). DOI: 10.1016/j.spc.2026.04.006

Comment by Dr. Krishna Kumari Challa 6 hours ago

UN warns world to prepare for El Nino extreme weather

There is an 80% probability of El Niño developing between June and August, with a likelihood near or above 90% by November. El Niño is expected to cause above-normal global temperatures and increase the risk of extreme weather events, including drought, heavy rainfall, and heat waves. Climate change does not increase El Niño frequency or intensity but can amplify its impacts. Regional forecasts indicate drier and warmer conditions in parts of Africa, South Asia, and Central America.

News Agencies

Comment by Dr. Krishna Kumari Challa 6 hours ago

Cutting a photon in two creates an infinite swarm of particles
Attempting to split a single photon using a fast optical shutter does not yield two smaller photons but instead generates a quantum superposition containing infinitely many photons due to disturbances in the electromagnetic field's quantum fluctuations. Locally, the system appears unchanged, but globally, the quantum state becomes highly complex, illustrating the non-classical behaviour of quantum particles.

Isak Cecil Onsager Rukan et al, Truncated photon, Physical Review Letters (2026). DOI: 10.1103/94pm-hp34. On arXiv: arxiv.org/abs/2510.21636

====

Embryonic tissues can behave like fluids or solids to reshape cell fate signals Tissue rigidity in embryonic development is actively regulated by cell-cell adhesion, not cell density, enabling transitions between fluid-like and solid-like states. Increased adhesion induces tissue stiffening, which restricts morphogen diffusion, spatially localizing developmental signals such as Nodal and influencing cell fate. Morphogen signaling can also enhance local tissue rigidity, creating a feedback loop between mechanical and biochemical processes.

Rustarazo-Calvo, L., et al. Adhesion-driven rigidity transition decoupled from density-driven jamming triggers epithelial organization in embryonic tissues., Nature Physics (2026). DOI: 10.1038/s41567-026-03276-6

Camilla Autorino et al, Tissue rigidity phase transition shapes morphogen gradients, Nature Cell Biology (2026). DOI: 10.1038/s41556-026-01954-4

Comment by Dr. Krishna Kumari Challa 6 hours ago

Exploding immune cells that kill surrounding tissue

 Scientists have discovered a new type of immune cell that kills surrounding cells via explosion—a cellular detonation so fast and complete that the cell vanishes within minutes, leaving no trace behind. This discovery comes from an unlikely source: planarian flatworms. These aquatic, slithering pancake versions of worms are famous for their ability to survive dismemberment and grow whole new organisms from the sliced-up segments of their formerly unified body. Understanding how these flatworms' immune systems have managed to endure for hundreds of millions of years could hold important insights for modern medicine.

In a new study published June 2 in Cell, the team describes the discovery and names these new cells "ruptoblasts" for their explosive response to a certain hormone.

A postdoctoral researcher first observed these cells while investigating the long-standing mystery in flatworm biology of whether or not they can tell the difference between their own tissues and those of another individual. To find out, she longitudinally sliced the flatworms and fused them together with a separate worm. Although adept at regrowing their own tissues, the researcher noted that these "Frankenstein" worms rejected halves of other worms, similar to how a human body may reject an organ transplant from a donor.

Unlike humans, however, a different cellular defense mechanism sprang into action.

It's this huge inflammatory response. Like there's a fire and an alarm goes off, and the cells just blow up.

Some mammalian cells and bacteria may also do an explosive sort of cell death, but the timescale is really long. They are exploding, but it's more like pores that slowly leak things out over the course of several hours. Ruptosis happens within seconds to minutes.

In a matchup against E. coli bacteria, human kidney cells, and mouse blood cells, ruptoblasts destroyed all three. Yet the authors noted that cell fatalities were limited to the immediate area of the explosion and did not trigger any sort of chain reaction or lingering toxicity. This localized effect holds promise for targeted treatments of bacterial infections or tumours.

Another characteristic that sets ruptoblasts apart from other immune cells, like T-cells or neutrophils, is the fact that they are glandular cells rather than hematopoietic cells, or blood cells produced in the bone marrow. The ruptoblasts seem to figure out a way to amplify their secretion machinery to suddenly and violently release cytotoxic substances in response to activin. A sharp increase in calcium from the endoplasmic reticulum within the ruptoblast helps facilitate the ruptosis.

In searching for these cells in other organisms,  the researchers discovered that they only appear in basal bilaterians like the flatworms, which points to these cells having early evolutionary origins.

The reason these cells were filtered out of modern vertebrate immune systems could be because vertebrates lack the ability to repair other cells after ruptosis occurs, unlike flatworms that are rich in stem cells.

Explosive cytotoxicity of ruptoblasts bridges hormone surveillance and immune defense, Cell (2026). DOI: 10.1016/j.cell.2026.05.008. www.cell.com/cell/fulltext/S0092-8674(26)00567-2

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