Worrying about the present and future of our warming planet has also provoked rising anxiety, depression and even post-traumatic stress—particularly for people already struggling with these disorders, psychologists have warned.
In the first 10 months of the year, people searched online for the term "climateanxiety" 27 times more than during the same period in 2017, according to data from Google Trends cited by the BBC this week.
Chocolate discharges the same chemical in your body as when you feel love. Chocolate raises levels of phenylethylamine (PEA), “the love chemical”. This chemical gets our hearts pumping, increases blood pressure, heart, and respiratory rates, and increases feelings of joy
Chocolate releases this neurochemical of pleasure in our brains. Dopamine kick starts a brain messenger chemical called DARP-32 that activates hormones. This is the chemical that surges through us when we are embraced by someone we love.
Chocolate contains tryptophan, a precursor to serotonin. Serotonin is our other feel good chemical. It diminishes anxiety and increases our ability to fight stress. Many antidepressants work by increasing serotonin levels.
So those who are not in love go eat chocolates and be happy.
How to make waves eat themselves Physicists have demonstrated that two cavities carved into the side of a channel can totally dissipate the energy of incoming waves. In a model set-up with real water, researchers were able to achieve ‘perfect absorption’ — in which the waves completely cancelled themselves out as they bounced off the cavity walls — with waves of a frequency of 2.9 Hertz. The finding hints at the possibility of designing structures to protect coastlines or harvest wave energy.
Meta AI develops a non-invasive method to decode speech from brain activity
Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks.
Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks. Researchers at Meta AI recently developed a promising and non-invasive method to decode speech from a person's brain activity, which could allow people who are unable to speak to relay their thoughts via a computer interface. Their proposed method, presented in Nature Machine Intelligence, merges the use of an imaging technique and machine learning.
Alexandre Défossez et al, Decoding speech perception from non-invasive brain recordings, Nature Machine Intelligence (2023). DOI: 10.1038/s42256-023-00714-5.
Scientists discover rare six-planet system that moves in strange synchrony
Scientists have discovered a rare sight in a nearby star system: Six planets orbiting their central star in a rhythmic beat. The planets move in an orbital waltz that repeats itself so precisely that it can be readily set to music.
A rare case of an "in sync" gravitational lockstep, the system could offer deep insight into planet formationand evolution.
The analysis, led by UChicago scientist Rafael Luque, waspublishedNov. 29 inNature.
The six planetsorbita star known as HD110067, which lies around 100 light-years away in the northern constellation of Coma Berenices.
In 2020, NASA's Transiting Exoplanet Survey Satellite (TESS) detected dips in the star's brightness that indicated planets were passing in front of the star's surface. Combining data from both TESS and the European Space Agency's CHaracterizing ExOPlanet Satellite (Cheops), a team of researchers analyzed the data and discovered a first-of-its-kind configuration.
While multi-planet systems are common in our galaxy, those in a tight gravitational formation known as "resonance" are observed by astronomers far less often.
In this case, the planet closest to the star makes three orbits for every two of the next planet out—called a 3/2 resonance—a pattern that is repeated among the four closest planets. Among the outermost planets, a pattern of four orbits for every three of the next planet out (a 4/3 resonance) is repeated twice.
And these resonant orbits are rock-solid: The planets likely have been performing this same rhythmic dance since the system formed billions of years ago, the scientists said.
Orbitally resonant systems are extremely important to find because they tell astronomers about the formation and subsequent evolution of the planetary system. Planets around stars tend to form in resonance but can be easily perturbed. For example, a very massive planet, a close encounter with a passing star, or a giant impact event can all disrupt the careful balance.
As a result, many of the multi-planet systems known to astronomers are not in resonance but look close enough that they could have been resonant once. However, multi-planet systems preserving their resonance are rare.
Nanodiamonds can block tumor metastasis in mice, study shows
Nanodiamonds are 2–8 nm carbon nanoparticles, which can be easily functionalized with various chemical groups like carboxylic groups or drugs. Previous research has shown that actively dividing cells are more likely to absorb nanodiamonds and that epithelial cells treated with carboxylic nanodiamonds lose the ability to migrate across cell-permeable cellulose membranes.
Researchers explored whether nanodiamonds might block tumor metastasis, a process that requires cell migration to new areas. The research is published in the journal PNAS Nexus.
The authors treated B16F10 melanoma cells with carboxylic nanodiamonds in culture and tested their ability to migrate and invade across polycarbonate membranes with 8-µm pores. The authors found that the nanodiamonds blocked the ability of melanoma cells to migrate, while untreated tumor cells were able to pass through the membrane.
Based on gene expression evidence, the authors hypothesize that the tiny carbon nanodiamonds may inhibit the breaking away of cancer cellsfrom the primary tumor mass—as well as block subsequent steps of metastasis such as the physical movement of cells and their ability to enter blood vessels.
According to the authors, nanodiamonds should be further explored as a possible therapeutic agent for cancer metastasis.
Sushreesangita P Behera et al, Carboxyl nanodiamonds inhibit melanoma tumor metastases by blocking cellular motility and invasiveness, PNAS Nexus (2023). DOI: 10.1093/pnasnexus/pgad359
A mineral produced by plate tectonics has a global cooling effect, study finds
Geologists have found that a clay mineral on the seafloor, called smectite, has a surprisingly powerful ability to sequester carbon over millions of years.
Under a microscope, a single grain of the clay resembles the folds of an accordion. These folds are known to be effective traps for organic carbon.
Now, the researchers have shown that the carbon-trapping clays are a product of plate tectonics: When oceanic crustcrushes against a continental plate, it can bring rocks to the surface that, over time, can weather into minerals including smectite. Eventually, the clay sediment settles back in the ocean, where the minerals trap bits of dead organisms in their microscopic folds. This keeps the organic carbon from being consumed by microbes and expelled back into the atmosphere as carbon dioxide.
Over millions of years, smectite can have a global effect, helping to cool the entire planet. Through a series of analyses, the researchers showed that smectite was likely produced after several major tectonic events over the last 500 million years. During each tectonic event, the clays trapped enough carbon to cool the Earth and induce the subsequent ice age.
The findings are the first to show that plate tectonics can trigger ice ages through the production of carbon-trapping smectite.
"Palaeozoic cooling modulated by ophiolite weathering through organic carbon preservation", Nature Geoscience (2023). DOI: 10.1038/s41561-023-01342-9
Brain waves usually found in sleep can protect against epileptic activity
Slow waves that usually only occur in the brain during sleep are also present during wakefulness in people with epilepsy and may protect against increased brain excitability associated with the condition, finds a new study by researchers.
The researchers examined electroencephalogram (EEG) scans from electrodes in the brains of 25 patients with focal epilepsy(a type of epilepsy characterized by seizures arising from a specific part of the brain), while they carried out an associative memory task.
The electrodes had been placed in the patients' brains to localize abnormal activity and inform surgical treatment.
During the task, participants were presented with 27 pairs of images that remained on a screen for six seconds. The images were in nine groups of three—each group featuring a picture of a person, a place and an object. In each case, participants had to remember which images had been grouped together. EEG data were recorded continuously throughout the task.
After reviewing the EEG data, the team found that the brains of people with epilepsy were producing slow waves—lasting less than one second—while they were awake and taking part in the task.
The occurrence of these "wake" slow waves increased in line with increases in brain excitability and decreased the impact of epileptic spikes on brain activity.
In particular, there was a decrease in the "firing" of nerve cells, which the researchers say could protect against epileptic activity.
Wake slow waves in focal human epilepsy impact network activity and cognition, Nature Communications (2023). DOI: 10.1038/s41467-023-42971-3
As dengue expands beyond the global 'dengue belt,' scientists dispel conventional wisdom about the disease
Unknowns, dangers and surprises persist about dengue viral infection and now an assumption once accepted as conventional wisdom about immunity to the mosquito-borne disease may be incorrect.
Dengue is a devastating viral infection transmitted to humans through the bite of Aedes aegypti mosquitoes—flying hypodermic needles that descend prolifically during significant outbreaks. Many dengue epidemics tend to occur in urban settings, scientists say. Dengue viral infection can cause a severe headache, high fever, nausea, vomiting, swollen glands, and rash. Still, and perhaps most surprisingly, many people who are infected have no symptoms at all. In rare cases, however, dengue disease can be fatal.
New research involving epidemiological models and data from more than 4,400 people in Nicaragua suggests that it's time immunologists developed a new framework to understand population immunity to dengue. For decades, it was believed that once you were infected with dengue virus, the immunity lasted for life. The dogma persisted in the face of observational data, which found that people who were previously infected were more susceptible to severe dengue if infected again.
But an international collaborative group of researchers has now conclusively shown that immunity not only wanes, it tends to wax and wane—a discovery that reveals dengue infection to be far more complex than previously thought.
According to them, Infection with multiple dengue virus serotypes is thought to induce enduring protection against dengue disease. However, long-term antibody waning has been observed after repeated dengue infection. The waning of antibodies inevitably was followed by a boosting of antibodies when the next epidemic came along.
This discovery allowed the construction of a new model that best describes population vulnerability to dengue infection, especially amid the known periodicity—the cyclic nature—of dengue outbreaks.
When it comes to dengue, people are not permanently immune but susceptible to infection, then immune and ultimately susceptible again. Hence, the researchers newly proposed a model: "susceptible-infected-recovered-susceptible."
Rosemary A. Aogo et al, Effects of boosting and waning in highly exposed populations on dengue epidemic dynamics, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.adi1734
New research suggests cellular stress in the placenta may be possible cause of preeclampsia
Preeclampsia is a mysterious condition that occurs in about one of 10 pregnancies without any early warning signs. After 20 weeks or more of normal blood pressure during the pregnancy, patients with preeclampsia will begin to experience elevated blood pressure and may also have increased levels of protein in their urine due to hypertension reducing the filtering power of the kidneys. Prolonged hypertension due to preeclampsia can lead to organ damage and life-threatening complications for mothers and fetuses.
There is no cure for the underlying causes of preeclampsia, so physicians focus on managing and monitoring patients' blood pressure to allow for as close to a full-term gestation as possible. With severe disease, pre-term deliveries are necessary.
For those who get it earlier on, it can be terrifying and life-changing, potentially including a long hospital stay before delivery and significant supportive care for the infant in the NICU afterwards.
Now scientists have published results on a study of one of the emerging theories for what causes preeclampsia in Science Advances.
The experiments focus on a particular layer of cells of the placenta called the syncytiotrophoblast (STB), which is a key part of the barrier between the mother and developing fetus. This blockade helps keep a mother's fully formed immune system from reacting to the fetus and potentially responding as if the fetus was a foreign threat such as a viral or bacterial invader.
The barrier also works in reverse to keep the fetus's growing immune system from reacting to its mother's cells and tissues. The study's authors investigated the hypothesis that an abnormal amount of cellular and molecular stresses to the STB can damage the placenta and lead to preeclampsia.
By comparing "normal" placentas with placentas from pregnancies where patients suffered from preeclampsia, investigators demonstrated that preeclampsia was associated with higher levels of cellular stresses in the STB layer on the placenta. Additionally, the researchers found a hyperactive level of activity of the Gαq protein known to play a role in transmitting signals related to the levels of several hormones present in excessive amounts during preeclampsia.
So, can preeclampsia be prevented? While today the answer is no, MCW scientists now are one step closer with these experimental results. And they are continuing to work as a team to achieve this goal through additional studies.
New discovery: Stunning River of Stars Flowing Through Space
A stunning river of stars has been spotted flowing through the intergalactic space in a cluster of galaxies about 300 million light years away.
Such bridges are known as stellar streams; and, at a length of 1.7 million light-years, the newly named Giant Coma Stream is the longest we've ever seen. And that's not all: the faint river is the first of its kind ever seen outside of a galaxy.
Two captive bottlenose dolphins (Tursiops truncatus) have now proved to researchers at the University of Rostock and Nuremberg Zoo in Germany that they can reliably sense weak electric fields in the water with their long snouts.
The discovery hints at the possibility that some marine mammals really can sniff out the electric currents of small prey buried in the sand. They might even use the skill to sense Earth's magnetic field.
To date, only one other 'true' placental mammal on Earth has been found to possess electroreceptors. Little more than a decade ago, scientists demonstrated that the common Guiana dolphin (Sotalia guianensis) evolved its own unique system of electroreception – one that is inherently different to fish, amphibians, and monotremes, like platypuses and echidnas.
Experiments now suggest that adult bottlenose dolphins and Guiana dolphins can both do something oddly similar with a line of sensitive pores on their snouts, called vibrissal crypts. These little holes used to hold juvenile whiskers, and they are extremely sensitive.
In experiments, bottlenose dolphins were able to use these ex-whisker pits to sense very weak electric fields as low as 2.4 and 5.5 microvolts per centimeter – a detection threshold that the researchers say is "in the same order of magnitude as those in the platypus" and also similar to Guiana dolphins.
Food Preserving Technique May Have Sparked Human Brain Growth: Researchers
Researchers propose that a taste for fermented morsels may have triggered a surprising jump in the growth rate of our ancestors' brains.
In fact, a shift from a raw diet to one that included food items already partially broken down by microbes may have been a crucial event in our brain's evolution,according to a perspective studyby evolutionary neuroscientists.
Human brains have tripled in size over the last two million years of evolution, while human colons have shrunk by an estimated 74 percent, suggesting a reduced need to break down plant-derived food internally.
We know the timeline and extent of human brain expansion, but the mechanisms allowing energy to be directed to this expansion are more complex and somewhat debated.
The study authors lay out their "external fermentation hypothesis" which shows our ancestors' metabolic circumstances for selective brain expansion may have been set in motion by moving intestinal fermentation to an external process, perhaps even experimenting with preserved foods not unlike the wine, kimchi, yoghurt, sauerkraut, and other pickles we still eat today.
The human gut microbiome acts like a machine for internal fermentation, which boosts nutrient absorption during digestion. Organic compounds are fermented into alcohol and acids by enzymes, usually produced by the bacteria and yeasts that live in parts of our digestive system such as our colon.
Fermentation is an anaerobic process, meaning it doesn't require oxygen, so similar to the process in our guts, it can occur in a sealed container. The process produces energy in the form of adenosine triphosphate (ATP), which is an essential source of chemical energy that powers our metabolism.
The researchers argue it's possible that culturally passed-down ways of handling or storing food encouraged this function to be externalized.
Externally fermented foods are easier to digest and contain more available nutrients than their raw equivalents. And since there's less for the colon to do if the food is already fermented, the organ's size could reduce over time while still potentially leaving energy available for brain growth.
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The brain sizes of our ancestors, the Australopiths, were similar to those of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). The human lineage's brain expansion accelerated with Homo's emergence and continued through Homo sapiens and Homo neanderthalensis.
How did our ancestors, with brains about the size of chimpanzees, manage to harness the power of external fermentation?
Researchers suggest that hominids with lower cognitive abilities and smaller brains may have adapted to fermentation much earlier than proposed alternative alternative explanations for this gut-to-brain energy redirection, like animal hunting and fire-based cooking. Fermentation has many advantages associated with cooked foods, such as softer textures, increased caloric content, improved nutrient absorption, and defense against harmful microorganisms. The researchers emphasize the need for empirical research to support or refute their hypothesis, such as microbiological studies, comparative analyses, and genetic and genomic investigations.
Brain implants revive cognitive abilities long after traumatic brain injury in clinical trial
A lady in her final semester of college, planning to apply to law school, when she suffered a traumatic brain injury in a car accident. The injury so compromised her ability to focus she struggled in a job sorting mail.
She couldn't remember anything . Her left foot dropped, so she'd trip over things all the time. She was always in car accidents. And she had no filter—she'd get pissed off really easily.
Her parents learned about research being conducted at Stanford Medicine and reached out; she was accepted as a participant. In 2018, physicians surgically implanted a device deep inside her brain, then carefully calibrated the device's electrical activity to stimulate the networks the injury had subdued. The results of the clinical trial were published Dec. 4 in Nature Medicine. She noticed the difference immediately. When she was asked to list items in the produce aisle of a grocery store, she could rattle off fruits and vegetables. Then a researcher turned the device off, and she couldn't name any. Since the implant she hadn't had any speeding tickets she said. She doesn't trip anymore. She can remember how much money is in her bank account. She wasn't able to read earlier, but after the implant she bought a book, 'Where the Crawdads Sing,' and loved it and remembered it. And she doesn't have that quick temper." For her and four others, the experimental deep-brain-stimulation device restored, to different degrees, the cognitive abilities they had lost to brain injuries years before. The new technique, developed by Stanford Medicine researchers and collaborators from other institutions, is the first to show promise against the long-lasting impairments from moderate to severe traumatic brain injuries.
Toxic chemicals in whales and dolphins are exceeding safe limits
Almost half of marine mammals around the UK are being poisoned by banned chemicals.
The compounds, once used in pesticides, flame retardants and coolants, are having significant impacts on the health and reproduction of the animals.
The UK's whales and dolphins are full of toxins—and it might only get worse.
Despite many being banned almost 20 years ago, levels of persistent organic pollutants (POPs) remain high in the oceans. In fact, these chemicals may breach safe limits in as many as half of all marine mammals living around the UK, based on a new study of stranded animals.
While the researchers found that levels of six key POPs are declining, they're concerned that the chemicals currently contained in coastal landfill sites could increasingly leak out as flooding, extreme weather and coastal erosion are enhanced by climate change.
What is alarming is this can happen anywhere in the world.
Rosie S. Williams et al, Spatiotemporal Trends Spanning Three Decades Show Toxic Levels of Chemical Contaminants in Marine Mammals, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c01881
Researchersextracted and sequenced DNA from inside the clay of an ancient brickfound in modern-day Iraq. They found genetic material from 34 taxonomic groups, including cabbage, heather, birch and cultivated grasses, in sun-dried bricks used to construct a palace in Mesopotamia (now part of Iraq) nearly 3,000 years ago.
Why this is so cool:Although scientists have previously extracted ancient DNA, or aDNA, from bones and lake sediments, they hadn't used existing techniques on clay bricks because the brick-baking process usually destroys biological material. The team also accurately dated this particular brick to within several decades (883–859 B.C.E.), thanks to an inscription on its side: “The property of the palace of Ashurnasirpal, king of Assyria.” The brick also listed the king in genealogical order, so the researchers could cross-check that against a list of known rulers from the time.
What the experts say:Archaeobotanists currently examine evidence of ancient plant life by using chemical processes or imaging microscopes; extracting aDNA “could potentially be a valuable addition,” say, an archaeobotanist.
Scientists observed a metal healing itself, something never seen before. If this process can be fully understood and controlled, we could be at the start of a whole new era of engineering.
In a study published in July, a research team was testing the resilience of the metal, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times every second. They then observed the self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum. Cracks caused by the kind of strain described above are known as fatigue damage: repeated stress and motion that causes microscopic breaks, eventually causing machines or structures to break. Amazingly, after about 40 minutes of observation, the crack in the platinum started to fuse back together and mend itself before starting again in a different direction.
Eye scans can provide crucial insights into kidney health, study finds
3D eye scans can reveal vital clues about kidney health that could help to track the progression of disease, research suggests. The advance could revolutionize the monitoring of kidney disease, which often progresses without symptoms in the early stages.
Experts say the technology has the potential to support early diagnosis as current screening tests cannot detect the condition until half of the kidney function has been lost. Researchers used highly magnified images to detect changes to the retina—the layer of tissue at the back of the eye that senses light and sends signals to the brain. They found that the images offer a quick, non-invasive way to monitor kidney health.
The eye is the only part of the body where it is possible to view a key process called microvascular circulation—and this flow of blood through the body's tiniest vessels is often affected in kidney disease.
investigated whether 3D images of the retina, taken using a technology called optical coherence tomography (OCT), could be used to identify and accurately predict the progression of kidney disease.
OCT scanners—used in most high street opticians—use light waves to create a cross-sectional picture of the retina, displaying each individual layer, within a few minutes.
The team looked at OCT images from 204 patients at different stages of kidney disease, including transplant patients alongside 86 healthy volunteers. They found that patients with chronic kidney disease had thinner retinas compared with healthy volunteers. The study also showed that thinning of the retina progressed as kidney function declined.
These changes were reversed when kidney function was restored following a successful transplant. Patients with the most severe form of the disease, who received a kidney transplant, experienced rapid thickening of their retinas after surgery.
This knowledge can be utilized in the future to identify the kidney ailments fast.
Neeraj Dhaun et al, Choroidal & retinal thinning in chronic kidney disease are modifiable with treatment & independently associate with eGFR decline, Nature Communications (2023). www.nature.com/articles/s41467-023-43125-1
More than 2.2 billion people currently live in water-stressed countries, and the United Nations estimates that 3.5 million die every year from water-related diseases. Because the areas most in need of improved drinking water are also located in some of the sunniest places in the world, there is strong interest in harnessing sunlight to help obtain clean water.
Researchers developed a promising new solar-powered atmospheric water harvesting technology that could help provide enough drinking water for people to survive in those difficult, dryland areas.
Historically, researchers have faced challenges when injecting salt into hydrogels as the higher salt content reduced the swelling capacity of the hydrogel due to the salting-out effect. This led to salt leakage and the water absorption capacity decreased.
The researchers synthesized a super hygroscopic gel using plant derivatives and hygroscopic salts that was capable of absorbing and retaining an unparalleled amount of water. One kilogram of dry gel could adsorb 1.18 kilograms of water in arid atmospheric environments and up to 6.4 kilograms in humid atmospheric environments. This hygroscopic gel was simple and inexpensive to prepare and would consequently be suitable for large-scale preparation.
In addition, the team adopted a prototype with desorption and condensation chambers, configured in parallel. They employed a turbofan in the condensation chamber to increase the recovery of desorbed water to more than 90%.
In an outdoor prototype demonstration, the team found it released adsorbed water even in the morning or afternoon when the sun is weak. The system could also achieve simultaneous adsorption and desorption during the daytime.
The team is trying to work to achieve simultaneous adsorption and desorption using renewable energy to maximize daily water yield per unit mass of adsorbent to further optimize the system's performance for practical applications in water generation.
Chengjie Xiang et al, Daytime air-water harvesting based on super hygroscopic porous gels with simultaneous adsorption-desorption, Applied Physics Reviews (2023). DOI: 10.1063/5.0160682
Even back in 1957, when Gordon Gould coined the term "laser" (short for "Light Amplification by Stimulated Emission of Radiation"), he was already imagining the possibilities for its use in medicine. Surgeons would be able to make precise incisions without even touching the patient.
Before that could happen, however, there were—and still are—many hurdles to overcome. Manually controlled light sources have been superseded by mechanical and computer-controlled systems to reduce injuries caused by clumsy handling. Switching from continuous beams to pulsed lasers, which turn themselves rapidly on and off, has reduced the heat they produce. Technical advances allowed lasers to enter the world of ophthalmology in the early 1990s. Since then, the technology has moved on in other areas of medicine, too, but only in relatively few applications has it replaced the scalpel and the bone saw.
Safety concerns are the most important hurdle: how can we prevent injury to the surrounding tissue? How closely can the cutting depth be controlled so that deeper layers of tissue are not accidentally damaged?
Researchers have just made an important contribution to the safe and precise use of lasers with their recent publication in the journal Lasers in Surgery and Medicine. They developed a system that combines three functions: it cuts bone, controls the cutting depth and differentiates between different tissues.
These three functions are carried out by three lasers that are aligned to focus on the same spot. The first laser serves as a tissue sensor in that it scans the surroundings of the site where the bone is to be cut.
Pulses are sent with this laser to the surface at regular intervals, so to speak, vaporizing a tiny bit of tissue each time. The composition of this vaporized tissue is measured with a spectrometer. Each type of tissue has its own individual spectrum—its own signature. An algorithm processes this data and creates a kind of map that shows where the bones are located and where the soft tissue is.
Not until all of this has been completed does the second laser, which cuts bone, activate, and then only in places where bones rather than soft tissue are shown on the map that has just been generated. At the same time, the third laser—an optical system—measures the depth of the cut and checks that the cutting laser is not penetrating more deeply than planned. During the cutting phase, the tissue sensor also constantly monitors whether the correct tissue is being cut.
The special thing about this system is that it controls itself—without human interference.
The researchers have so far been testing their system on femur bones and tissue from pigs acquired from a local butcher. They were able to prove that their system works accurately down to fractions of a millimeter. The speed of the combined laser also approaches that of a conventional surgical procedure.
The research team is currently working on making the system smaller.
Arsham Hamidi et al, Multimodal feedback systems for smart laser osteotomy: Depth control and tissue differentiation,Lasers in Surgery and Medicine(2023).DOI: 10.1002/lsm.23732Arsham Hamidi et al,
Towards miniaturized OCT-guided laser osteotomy: integration of fiber-coupled Er:YAG laser with OCT,Optics Continuum(2023).DOI: 10.1364/OPTCON.497483
Scientist Rebellion is composed of thousands of climate researchers, academics, and concerned citizens who are urging people to get involved in the effort to limit global overheating. As part of the COP 28 proceedings, Scientist Rebellion is urging people to sign an open letter pleading for governments to heed the climate science and take meaningful action while there is still time.
IBM has unveiled thefirst quantum computer with 1,121 superconducting qubits(qubits are the quantum equivalent of digital bits in a classical computer). Quantum computers could outperform classical computers in certain areas by exploiting phenomena such as entanglement and superposition. However, these quantum states are notoriously fickle and prone to error, so simply having more qubits does not necessarily make a system better. IBM says it will now focus on more error-resistant systems, rather than larger ones.
Earliest mosquito was a bloodsucking male The discovery of the earliest known fossil mosquitoes, preserved in Lebanese amber, had a sting in the tail: the insects were bloodsucking males. Today, only female mosquitoes eat blood, with males living on nectar and plant juices. The 125-million-year-old fossils have mouthparts that look perfect for piercing skin, as well as mate-grabbing appendages that confirm their sex. The finding could turn current thinking — that blood-sucking evolved after plant-eating — on its head. “We think now that, originally, the mosquito could be bloodsucking,” says palaeontologist and study co-author Dany Azar. “With the appearance of the flowering plant, this function could be just forgotten later on.”
Could Blood Transfusions and Tissue Transplants Spread Certain Dementias?
Scattered evidence suggests that aberrant proteins act as “seeds” to transmit neurodegenerative disease, but the jury is still out
In the last several years, scientists have begun investigating whether neurodegenerative diseases like Alzheimer’s and Parkinsons can be contagious. One misfolded protein, scientists hypothesize, might somehow ensnare other proteins and cause them to misfold, leading to plaque build-up in the brain. If a malfunctioning protein somehow finds its way into another individual, could it launch a similar accumulation of proteins?
What they've found: In 2015 researchers reported a curious buildup of the protein plaque associated with some dementias in young to middle-age adults who had received childhood injections of human growth hormone extracted from the pituitary glands of cadavers. And in 2018 doctors recorded unusual cases of cerebral amyloid angiopathy, a condition marked by amyloid buildup in cerebral blood vessels; because these young adults had brain surgery in childhood, the researchers suspect that contaminated surgical tools transferred the “seeds” of plaque accumulation to the patients’ brains.
Why this matters: Learning how prionlike diseases “spread” might launch treatments that interrupt their replication and accumulation. Early studies in mice have shown that amyloid antibodies can clear plaque build up, which aligns with recent trials of new Alzheimer’s treatments that show how removing brain amyloid can slow cognitive decline. If protein misfolding is contagious, we may have a new way to interrupt the devastation it causes.
Research shows mouse and primate brains mature at same pace
A new study has revealed that short-lived mice and longer-living primates develop brain synapses on the exact same timeline, challenging assumptions about disease and aging. What does this mean for humans—and yesterday's research?
Mice typically live two years and monkeys live 25 years, but the brains of both appear to develop their synapses at the same time. This finding, the result of a recent study has puzzled neuroscientists.
Until now, brain development was understood as happening faster in mice than in other, longer-living mammals such as primates and humans. Those studying the brain of a 2-month-old mouse, for example, assumed the brain was already finished developing because it had a shorter overall lifespan in which to develop. In contrast, the brain of a 2-month-old primate was still considered going through developmental changes. Accordingly, the 2-month-old mouse brain was not considered a good comparison model to that of a 2-month-old primate. That assumption appears to be completely wrong, which the authors think will call into question many results using young mouse brain data as the basis for research into various human conditions, including autism and other neurodevelopmental disorders.
Gregg Wildenberg et al, Isochronic development of cortical synapses in primates and mice, Nature Communications (2023). DOI: 10.1038/s41467-023-43088-3
New study concludes finding cure for malaria may be even more challenging than thought
Researchers who have studied malaria for decades, hoping to find a cure, long thought they'd identified a type of blood that seemed to defend against the disease. But a new study published in Cell Host & Microbe concludes that even some people with the protective blood type became infected. The question now is, how? "This might mean that the specific gene mutation related to this blood type doesn't completely stop malaria, or the malaria bug might have found another way to get into the blood cells," said Peter Zimmerman, a pathology professor at Case Western Reserve University School of Medicine and the study's senior author. "It's a big deal because it might change how we try to get rid of this type of malaria parasite." "This malaria parasite, called Plasmodium vivax—or P. vivax—used to be common in Northeast Ohio," said Christopher King, a study co-investigator and pathology professor. "And it was transmitted within the United States—Florida and Texas—this summer for the first time in 20 years.
"We have known," King said, "that the United States is at risk of re-introduction of malaria with climate changes and increasing immigration and traveling from malaria-endemic areas."
Study collaborators include researchers from France (Célia Dechavanne and Benoit Gamain, from the National Institute of Blood Transfusion, INSERM/Paris Diderot University); and Madagascar (Arsène Ratsimbasoa, from the University of Fianarantsoa).
Part 1
"Malaria researchers have been trying to chip away at understanding resistance and susceptibility of P. vivax infection of African people for more than 100 years," Zimmerman said. "More than 2.5 billion people may live in Africa and Southeast Asia where the parasite is found. Hundreds of thousands of people a year die from malaria. In general, malaria is one of the big three global-health infectious diseases—malaria, tuberculous and HIV/AIDS."
The team is studying a specific blood type (Fy-negative) in the blood of most people in Africa and of African origin, called "the silent Duffy blood group." Duffy-negative people have a mutation in the DNA code (GATA-1) that results in the protein not being expressed on the surface of red blood cells.
The researchers did experiments using blood cells grown in the lab and cells taken from bone marrow to study the Duffy-silent blood type.
"Surprisingly, we found that even when people are missing the GATA-1 DNA code, the Duffy protein sometimes shows up on their red blood cells," Zimmerman said. "Our findings suggest that the bone marrow and other places where blood cells are first made are important for the malaria parasite to find the red cells with the Duffy protein, to grow and cause sickness."
In other experiments in the lab, they examined the blood of people with Duffy silent blood type. They noticed the P. vivax malaria infection was often detected using a special test rather than the usual microscope test.
This means that people with Duffy-silent blood type can still have the infection, but it's not always easy to see in regular blood tests. In other words, they found that P. vivax can invade the red blood cells of people with the Duffy-silent trait. Also, if they have the infection in the bone marrow, they produce the transmissible form of the parasite. Mosquitoes can acquire it and cause infections in other people.
"This discovery raises questions about how malaria parasites cause infection and sickness, especially because some people with the infection don't show many signs in their blood," Zimmerman said. "We need to look at the blood more closely to understand better how widespread and serious this type of malaria is in people with the Duffy-silent trait."
Celia Dechavanne et al, Duffy antigen is expressed during erythropoiesis in Duffy-negative individuals, Cell Host & Microbe (2023). DOI: 10.1016/j.chom.2023.10.019
Study finds sleep can improve memory retention but can also imprint false memories
A team of psychologists has found via experimentation that sleeping after studying can consolidate memories. But, as they note in their paper published in the journal Royal Society Open Science, sleep can also sometimes lead to the creation of false memories.
Recent research efforts have shown that human memory is not nearly as accurate as it may feel to someone who is recalling a memory of a thing or event—findings that have called into question eyewitness accounts at criminal trials. Such results have led to more study of memory retention and recall as a way to learn more about the ways that memory works.
For this new research, 488 volunteersstudied a list of related words and then to attempt to recall those words 12 hours later. To learn about the impact of sleep on retention, some of the volunteers were allowed to sleep between the time they viewed the original list and the time of the memory retention testing.
The researchers found that those people who were allowed to sleep during the interim scored better on memory retention. But they also found that they were more likely to believe falsely that some related words were on the list. As an example, when given a list such as "nurse, hospital and surgery," people who had been allowed to sleep were more likely to falsely believe the word "doctor" had also appeared on the list.
The researchers suggest this finding shows that the purpose of memory is not necessarily to give people an accurate assessment of things that have occurred, but to give them a means for retrieving the gist of things. As humans evolved, it was important that connections and associations be made as part of the learning process in order to better prepare for future threats.
The research team also found that the time of day the volunteers were questioned about the list had an impact on recall accuracy—both groups made more errors and falsely recalled more words when questioned during the evening.
Matthew H. C. Mak et al, A registered report testing the effect of sleep on Deese-Roediger-McDermott false memory: greater lure and veridical recall but fewer intrusions after sleep, Royal Society Open Science (2023). DOI: 10.1098/rsos.220595
A possible way for early life on Earth to survive cosmic radiation
A team of biophysicists has uncovered via experimentation the means by which early life might have been able to survive cosmic radiation. In their study, reported in the journal Nature Communications, the group conducted experiments with radiation-resistant manganese antioxidants.
Prior research has shown that the Earth was formed approximately 4.5 billion years ago, and that life arose approximately a half-billion years later. Prior research has also shown that the Earth's magnetic field did not start protecting life from cosmic radiation until approximately 3.5 billion years ago. This leads to questions about how life was able to begin and flourish in those early years.
A type of bacteria known as Deinococcus radiodurans has been shown to be capable of surviving levels of radiation that would kill most other living creatures. Study of this bacteria reveals that it is able to do so because of the amount of Mn(II) (manganese) ions in its body—it serves to protect the tiny creatures from the oxidative stress that would occur in other bacteria that do not have it. This finding has led to theories that suggest harboring of Mn(II) ions is the means by which early life survived on Earth.
To test this theory, the research team created models they describe as protocells—such "coacervates" were used to serve as stand-ins for early life protocells on Earth. The team used two types, one based on polyphosphate manganese, the other based on polyphosphate peptides. When exposed to high levels of gamma rays, the polyphosphate–manganese coacervates remained intact and viable. The polyphosphate–peptide coacervates, on the other hand, were destroyed. Prior research has shown that polyphosphate manganese has been present on Earth longer than life has existed, likely produced during volcanic activity—thus, it would have been available for use by protocells as a means of protection. The researchers suggest that early protocells on Earth were able to survive due to protection by material similar to polyphosphate manganese. Such protocells, they note, would have been able to survive long enough to develop into cyanobacteria and eventually eukaryotic cells, which would have been protected by the Earth's magnetic field and ozone layer.
Shang Dai et al, An inorganic mineral-based protocell with prebiotic radiation fitness, Nature Communications (2023). DOI: 10.1038/s41467-023-43272-5
Researchers show that an influx of water and salts propel immune cells through the body
Researchers have shown that an influx of water and ions into immune cells allows them to migrate to where they're needed in the body.
Our bodies respond to illness by sending out chemical signals called chemokines, which tell immune cells called T cells where to go to fight the infection. This process had already been associated with a protein called WNK1, which activates channels on the cell surface, allowing ions (salts like sodium or potassium) to move into cells. Until now, it was not clear why ion influx was needed for T cells to move.
Through a study published in Nature Communications, the researchers imaged mouse T cells and observed that, following a chemokine signal, WNK1 is activated at the front of the cells, called the "leading edge." The team showed that the activation of WNK1 opens channels on the leading edge, resulting in an influx of water and ions. They propose that this flow of water causes the cells to swell on the front side, creating space for the 'actin cytoskeleton'—the scaffolding inside the cell that holds its structure—to grow into. This propels the whole cell forward and the process repeats again. The researchers used gene editing to stop mice producing WNK1, or an inhibitor to prevent WNK1's activity, observing that the T cells in these mice slowed down or stopped moving completely. Importantly, they found that they could make up for the loss of WNK1 and make the cells speed up by dropping them into a watery solution, which causes the cells to take up water and swell. This shows that the uptake of water, controlled by the WNK1 protein is key for the cells to migrate.
The researchers think that the mechanism they've discovered could be involved in lots of different cell types beyond immune cells.
Leonard L. de Boer et al, T cell migration requires ion and water influx to regulate actin polymerization, Nature Communications (2023). DOI: 10.1038/s41467-023-43423-8
Study finds climate change can cause methane to be released from the deep ocean
New research has shown that fire-ice—frozen methane which is trapped as a solid under our oceans—is vulnerable to melting due to climate change and could be released into the sea.
An international team of researchers found that as frozen methane and ice melts, methane—a potent greenhouse gas—is released and moves from the deepest parts of the continental slope to the edge of the underwater shelf. They even discovered a pocket that had moved 25 miles (40 kilometers). Publishing in the journal Nature Geoscience, the researchers say this means that much more methane could potentially be vulnerable and released into the atmosphere as a result of climate warming.
Methane hydrate, also known as fire-ice, is an ice-like structure found buried in the ocean floor that contains methane. Vast amounts of methane are stored as marine methane under oceans. It thaws when the oceans warm, releasing methane into oceans and the atmosphere—known as dissociated methane—contributing to global warming.
The scientists used advanced three-dimensional seismic imaging techniques to examine the portion of the hydrate that dissociated during climatic warming off the coast of Mauritania in Northwest Africa. They identified a specific case where dissociated methane migrated over 40 kilometers and was released through a field of underwater depressions, known as pockmarks, during past warm periods.
Planet tipping points pose 'unprecedented' threat to humanity: report
Humanity faces an "unprecedented" risk from tipping points that could unleash a domino effect of irreversible catastrophes across the planet, researchers warned this week.
The most comprehensive assessment ever conducted of Earth's invisible tripwires was released as leaders meet for UN climate talks in Dubai with 2023 set to smash all heat records. While many of the 26 tipping points laid out in the report—such as melting ice sheets—are linked to global warming, other human activities like razing swathes of the Amazon rainforest could also push Earth's ecosystems to the brink. Five of these are showing signs of tipping—from melting ice sheets threatening catastrophic sea level rise, to mass die-off of tropical coral reefs—the report warned. Some may have already begun to irrecoverably transform. Once the world crosses the threshold for just one tipping point, dealing with the immediate humanitarian disaster could distract attention away from stopping the others, creating a "vicious cycle" of mass hunger, displacement and conflict, the report warned.
The risks for humanity in crossing tipping points into these unexplored states is dire, and the impact to human lives potentially horrific.
Warfare ruins the environment—and not just on the front lines
On the morning of December 6, 1917, a French cargo ship called SS Mont-Blanc collided with a Norwegian vessel in the harbor of Halifax in Nova Scotia, Canada. The SS Mont-Blanc, which was laden with 3,000 tons of high explosives destined for the battlefields of the first world war, caught fire and exploded. The resulting blast released an amount of energy equivalent to roughly 2.9 kilotons of TNT, destroying a large part of the city. Although it was far from the front lines, this explosion left a lasting imprint on Halifax in a way that many regions experience environmental change as a result of war. The attention of the media is often drawn to the destructive explosions caused by bombs, drones or missiles. And the devastation we have witnessed in cities like Aleppo, Mosul, Mariupol and now Gaza certainly serve as stark reminders of the horrific impacts of military action. However, research is increasingly uncovering broader and longer-term consequences of war that extend well beyond the battlefield. Armed conflicts leave a lasting trail of environmental damage, posing challenges for restoration after the hostilities have eased.
Ancient stars made extraordinarily heavy elements, researchers find
How heavy can an element be? An international team of researchers has found that ancient stars were capable of producing elements with atomic masses greater than 260, heavier than any element on the periodic table found naturally on Earth. The finding deepens our understanding of element formation in stars.
We are, literally, made of star stuff. Stars are element factories, where elements constantly fuse or break apart to create other lighter or heavier elements. When we refer to light or heavy elements, we're talking about their atomic mass. Broadly speaking, atomic mass is based on the number of protons and neutrons in the nucleus of one atom of that element.
The heaviest elements are only known to be created in neutron stars via the rapid neutron capture process, or r-process. Picture a single atomic nucleus floating in a soup of neutrons. Suddenly, a bunch of those neutrons get stuck to the nucleus in a very short time period—usually in less than one second—then undergo some internal neutron-to-proton changes, and voila! A heavy element, such as gold, platinum or uranium, forms.
The heaviest elements are unstable or radioactive, meaning they decay over time. One way that they do this is by splitting, a process called fission.
The r-process is necessary if you want to make elements that are heavier than, say, lead and bismuth.
You have to add many neutrons very quickly, but the catch is that you need a lot of energy and a lot of neutrons to do so. And the best place to find both are at the birth or death of a neutron star, or when neutron stars collide and produce the raw ingredients for the process.
The team took a fresh look at the amounts of heavy elements in 42 well-studied stars in the Milky Way. The stars were known to have heavy elements formed by the r-process in earlier generations of stars. By taking a broader view of the amounts of each heavy element found in these stars collectively, rather than individually as is more common, they identified previously unrecognized patterns.
Part 1
Those patterns signaled that some elements listed near the middle of the periodic table—such as silver and rhodium—were likely the remnants of heavy element fission. The team was able to determine that the r-process can produce atoms with an atomic mass of at least 260 before they fission.
That 260 is interesting because we haven't previously detected anything that heavy in space or naturally on Earth, even in nuclear weapon tests.
Physicists 'entangle' individual molecules for the first time, hastening possibilities for quantum computing
For the first time, a team of physicists have been able to link together individual molecules into special states that are quantum mechanically "entangled." In these bizarre states, the molecules remain correlated with each other—and can interact simultaneously—even if they are miles apart, or indeed, even if they occupy opposite ends of the universe. This research was recently published in the journal Science.
This is a breakthrough in the world of molecules because of the fundamental importance of quantum entanglement. And it is also a breakthrough for practical applications because entangled molecules can be the building blocks for many future applications.
These include, for example, quantum computers that can solve certain problems much faster than conventional computers, quantum simulators that can model complex materials whose behaviors are difficult to model, and quantum sensors that can measure faster than their traditional counterparts.
To entangle the molecules, they had to make the molecule interact. By using a series of microwave pulses, they were able to make individual molecules interact with one another in a coherent fashion.
By allowing the interaction to proceed for a precise amount of time, they were able to implement a two-qubit gate that entangled two molecules. This is significant because such an entangling two-qubit gate is a building block for both universal digital quantum computing and for simulation of complex materials.
Scientists create 'cloaked' donor cell, tissue grafts that escape immune system rejection
Immune rejection poses a major challenge in donor cell therapy. Transplant and cell therapy patients are required to take immunosuppressive drugs – sometimes for the rest of their lives – to prevent their bodies from rejecting the transplant. The extended use of these drugs can lead to serious health issues, including recurring infections and an elevated cancer risk.
Scientists worldwide have been exploring various solutions, including creating therapeutic cells from the patient’s own cells or encapsulating donor cells in inorganic material for protection.
But these methods face challenges such as high costs, long preparation times and foreign body immune response, complicating their widespread and cost-effective application.
Researchers now have developed a technology that may one day eliminate the need for immunosuppressive drugs in transplant patients. Through genetic modification of donor cells, the researchers successfully created transplants that persisted long-term in pre-clinical testing without the need for immune suppression. The findings raise hope that a similar strategy could be employed in human patients, potentially making transplantation safer and more widely available.
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Stem cells have the unique ability to divide indefinitely and give rise to specialized cells that form our organs. They make an ideal source for cell therapies as large numbers of cells can be obtained and converted into desired cell types to replace those lost to disease or injury.
But there are major safety concerns: in addition to addressing immune-matching, scientists must ensure that no unwanted dividing cells remain in the transplant that could cause cancer in the future.
Researchers selected eight key genes that regulate how the immune system responds to threats, including foreign cells. Forced overexpression of these genes in mouse embryonic stem cells prevented the immune system from recognizing them as foreign.
The modification effectively created an immune cloak around the cells following their injection under the skin of genetically unmatched hosts.
This study demonstrates the combined potential of FailSafe and immune cloaking for the creation of a universal source of cells that could be applied to a multitude of diseases.
Uncloaked cells are typically rejected within 10 days of transplantation. In contrast, the cloaked cells persisted for more than nine months at the endpoint of the experiment. This is the first time that scientists have been able to achieve this length of time without rejection in a fully functional immune system.
In another key finding, the researchers showed that unmodified cells can escape rejection when embedded into the tissue created by the cloaked donor cells below the skin surface. The protection extended to cells from another species, as shown by the ability of unmodified human cells to survive within a cloaked mouse graft.
This suggests that modified cells also act as an immune-privileged implantation site for unmodified cells, with implications for interspecies transplants. Researchers at other institutions are exploring the potential of pigs as donors because their organs are very similar in size and function to humans.
Study reveals genes that set humans apart from other primates in cognitive ability
An international team of researchers has uncovered over 100 genes that are common to primate brains but have undergone evolutionary divergence only in humans – and which could be a source of our unique cognitive ability.
They found the genes are expressed differently in the brains of humans compared to four of our relatives – chimpanzees, gorillas, macaques and marmosets.
The findings, published in Nature Ecology & Evolution, suggest that reduced selective pressure, or tolerance to loss-of-function mutations, may have allowed the genes to take on higher-level cognitive capacity. The study is part of the Human Cell Atlas, a global initiative to map all human cells to better understand health and disease. This research contributes to our understanding of differences in the brain between humans and other primates at the cellular level, but it has also resulted in a database that can be used to further characterize genetic similarities and differences across primates.
In all, the team found 139 genes that are common across the primate groups but highly divergent in their expression in human brains. These genes displayed a stronger ability to withstand mutations without impacting their function, suggesting they may have evolved under more relaxed selective pressure.
The genes that have diverged in humans must be tolerant to change. This manifests as tolerance to loss-of-function mutations, and seems to allow for rapid evolutionary change in the human brain.
Our higher cognitive function may have resulted from the adaptive evolution of human brain cells to a multitude of less threatening mutations over time. It’s also worth noting that around a quarter of the human-divergent genes identified in the study are associated with various brain disorders.
The divergent genes the researchers identified are found in 57 brain cell types, grouped by inhibitory neurons, excitatory neurons and non-neurons. A quarter of the genes were only expressed differently in neuronal cells, also known as grey matter, and half were only expressed differently in glial cells, which are white matter.
Grey matter in the brain consists of neurons, while white matter consists of other cell types, including those responsible for vasculature and immune function.
Self-copying RNA vaccine wins approval Japanese regulators have approved a COVID-19 vaccine constructed using a form of RNA that can make copies of itself inside cells. It’s the first ‘self-amplifying’ RNA (saRNA) vaccine platform to be granted full regulatory approval anywhere in the world. Because it could be used at a lower dose, it might have fewer side effects than other messenger RNA (mRNA) treatments have. When used as a booster in clinical testing, the newly authorized vaccine, ARCT-154 — developed by US biotechnology firm Arcturus Therapeutics and Australia-based CSL — triggered higher levels of virus-fighting antibodies that circulated the body for longer than did a standard mRNA COVID-19 vaccine.
Electricity from electric eels may transfer genetic material to nearby animals
The electric eel is the biggest power-making creature on Earth. It can release up to 860 volts, which is enough to run a machine. In a recent study, a research group found electric eels can release enough electricity to genetically modify small fish larvae. They published their findings in PeerJ.
The researchers' findings add to what we know about electroporation, a gene delivery technique. Electroporation uses an electric field to create temporary pores in the cell membrane. This lets molecules, like DNA or proteins, enter the target cell.
To test this, they exposed the young fish in their laboratory to a DNA solution with a marker that glowed in the light to see if the zebrafish had taken the DNA. Then, they introduced an electric eel and prompted it to bite a feeder to discharge electricity.
Electroporation might happen in nature. Researchers realized that electric eels in the Amazon River could well act as a power source, organisms living in the surrounding area could act as recipient cells, and environmental DNA fragments released into the water would become foreign genes, causing genetic recombination in the surrounding organisms because of electric discharge.
The researchers discovered that 5% of the larvae had markers showing gene transfer. "This indicates that the discharge from the electric eel promoted gene transfer to the cells, even though eels have different shapes of pulse and unstable voltage compared to machines usually used in electroporation. Electric eels and other organisms that generate electricity could affect genetic modification in nature.
Other studies have observed a similar phenomenon occurring with naturally occurring fields, such as lightning, affecting nematodes and soil bacteria.
Shintaro Sakaki et al, Electric organ discharge from electric eel facilitates DNA transformation into teleost larvae in laboratory conditions, PeerJ (2023). DOI: 10.7717/peerj.16596
The zebrafish larvae and a DNA solution were put into a small container and placed inside the tank where the electric eel produces electric pulses when it is fed by the experimenter.
Six-million-year-old groundwater pool discovered deep under Sicilian mountains
A multi-institutional team of geoscientists has discovered a deep, ancient underground pool of fresh water underneath part of the Sicilian mountains. In their study, reported in the journal Communications Earth & Environment, the group used publicly available data gathered from oil discovery efforts to study the groundwater in and around the Gela formation beneath the mountains on the island of Sicily.
The researchers analyzed maps and data from prior surveys looking for oil deposits. They discovered what they believe to be a previously unknown aquifer thousands of feet below the Hyblaean Mountains. They made 3D models of the aquifer to validate their findings and found evidence suggesting that not only is it an aquifer, but it holds approximately 17.5 cubic kilometers of water. The team then set out to explain how so much fresh water could have come to reside, locked in, beneath a mountain range. They suggest it was trapped there during the Messinian salinity crisis millions of years ago—the 700,000-year period saw a blockage at the Strait of Gibraltar that allowed many parts of the Mediterranean Sea to dry up, exposing the seafloor to rainwater. The research team suggests that this rainwater trickled down into the crust. Such rainwater, the researchers note, could have accumulated underground as it was soaked up by carbonate rock acting as a sponge. When sea levels returned to normal, the underground fresh water was locked in due to seawater pressure.
Lorenzo Lipparini et al, Extensive freshened groundwater resources emplaced during the Messinian sea-level drawdown in southern Sicily, Italy, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-01077-w
Genetic mutations that promote reproduction tend to shorten human lifespan, study shows
A study based on a review of genetic and health information from more than 276,000 people finds strong support for a decades-old evolutionary theory that sought to explain aging and senescence.
In 1957, evolutionary biologist George Williams proposed that genetic mutations that contribute to aging could be favored by natural selection if they are advantageous early in life in promoting earlier reproduction or the production of more offspring.
Now known as the antagonistic pleiotropy theory of aging, remains the prevailing evolutionary explanation of senescence, the process of becoming old or aging.
This theory was tested now.
The researchers found reproduction and lifespan to be genetically strongly negatively correlated, meaning that genetic mutationsthat promote reproduction tend to shorten lifespan.
In addition, individuals carrying mutations that predispose them to relatively high reproductive rates have lower probabilities of living to age 76 than those carrying mutations that predispose them to relatively low reproductive rates, according to the study.
However, the authors caution that reproduction and lifespan are affected by both genes and the environment. And compared with environmental factors—including the impacts of contraception and abortion on reproduction and medical advances on lifespan—the genetic factors discussed in the study play a relatively minor role, according to the authors. These results provide strong support for the Williams hypothesis that aging arises as a byproduct of natural selection for earlier and more reproduction. Natural selection cares little about how long we live after the completion of reproduction, because our fitness is largely set by the end of reproduction.
Fitness is a concept biologists use to describe the degree to which an organism's characteristics increase its number of offspring.
The researchers now found that when you control for the genetically predicted amount and timing of reproduction, having two kids corresponds to the longest lifespan. Having fewer or more kids both lower the lifespan. That result supports the findings of several previous studies.
In genetics, the concept of pleiotropy posits that a single mutation can influence multiple traits. The idea that the same mutation can be both beneficial and harmful, depending on the situation, is known as antagonistic pleiotropy and was proposed by Williams to underlie the origin of aging in a paper titled "Pleiotropy, natural selection, and the evolution of senescence."
To a biologist, senescence refers specifically to a gradual decline of bodily functions that manifests as a decline in reproductive performance and an increase in the death rate with age.
Compared with environmental factors, genetic factors play a minor role in the human phenotypic changes studied here.
Researchers discover a mechanism that controls the identity of stem cells
Researchers discovered a mechanism that controls the identity of stem cells. When this mechanism fails, embryonic stem cells revert back in time and become totipotent (totipotent embryo cells can differentiate into a hundred different cell types specialized to form such tissues as skin, marrow, and muscle).
When a cell becomes totipotent, this rare change enables the cells to differentiate into hundreds of cell types, and then go on to form every part of our body. This contrasts with pluripotent stem cells, which can divide into various cell types but are unable to become an entire organism solely on their own.
In a dish of embryonic stem cells, the majority of stem cells are pluripotent. However, 1 out of 1,000 cells are different from the rest, and are totipotent. Totipotent cells are the only cells that have unlimited potential and can give rise to all parts of our body. Scientists now discovered the mechanism that allows this change from pluripotent to totipotent.
Denis Torre et al, Nuclear RNA catabolism controls endogenous retroviruses, gene expression asymmetry, and dedifferentiation, Molecular Cell (2023). DOI: 10.1016/j.molcel.2023.10.036
Rich nations need to ditch fossil fuels by 2040: scientists
Rich countries need to stop using coal by 2030 and oil and gas by 2040, with poorer nations following a decade behind, to give the world a chance of limiting warming to 1.5C, climate scientists told the UN this week.
In a note to the UN Secretary-General Antonio Guterres and UN Climate Change body, shared with AFP, climate scientists said there was very little room for anything but a total phase-out of fossil fuels.
The steep timeline they laid out comes as climate negotiators at the COP28 talks in Dubai are tussling over the future of oil, gas and coal, responsible for the lion's share of humanity's planet-heating emissions.
The UN climate negotiations are tasked with helping the world meet the Paris deal goal of limiting global warming to 1.5 degrees Celsius from pre-industrial levels, but have often been vague on how that target will be achieved.
The discussions should be around serious and fair efforts to start implementing a phase out plan: scientists
Last week, reports emerged that the Israel Defense Forces (IDF) are using an artificial intelligence (AI) system called Habsora (Hebrew for "The Gospel") to select targets in the war on Hamas in Gaza. The system has reportedly been used to find more targets for bombing, to link locations to Hamas operatives, and to estimate likely numbers of civilian deaths in advance.
Dr. Krishna Kumari Challa
Worrying about the present and future of our warming planet has also provoked rising anxiety, depression and even post-traumatic stress—particularly for people already struggling with these disorders, psychologists have warned.
In the first 10 months of the year, people searched online for the term "climate anxiety" 27 times more than during the same period in 2017, according to data from Google Trends cited by the BBC this week.
Source:
The Lancet and AFP
Part 4
Nov 28, 2023
Dr. Krishna Kumari Challa
Chocolate discharges the same chemical in your body as when you feel love.
Chocolate raises levels of phenylethylamine (PEA), “the love chemical”. This chemical gets our hearts pumping, increases blood pressure, heart, and respiratory rates, and increases feelings of joy
Chocolate releases this neurochemical of pleasure in our brains. Dopamine kick starts a brain messenger chemical called DARP-32 that activates hormones. This is the chemical that surges through us when we are embraced by someone we love.
Chocolate contains tryptophan, a precursor to serotonin. Serotonin is our other feel good chemical. It diminishes anxiety and increases our ability to fight stress. Many antidepressants work by increasing serotonin levels.
So those who are not in love go eat chocolates and be happy.
Nov 28, 2023
Dr. Krishna Kumari Challa
How to make waves eat themselves
Physicists have demonstrated that two cavities carved into the side of a channel can totally dissipate the energy of incoming waves. In a model set-up with real water, researchers were able to achieve ‘perfect absorption’ — in which the waves completely cancelled themselves out as they bounced off the cavity walls — with waves of a frequency of 2.9 Hertz. The finding hints at the possibility of designing structures to protect coastlines or harvest wave energy.
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.204002
Nov 28, 2023
Dr. Krishna Kumari Challa
Meta AI develops a non-invasive method to decode speech from brain activity
Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks.
Recent technological advancements have opened invaluable opportunities for assisting people who are experiencing impairments or disabilities. For instance, they have enabled the creation of tools to support physical rehabilitation, to practice social skills, and to provide daily assistance with specific tasks. Researchers at Meta AI recently developed a promising and non-invasive method to decode speech from a person's brain activity, which could allow people who are unable to speak to relay their thoughts via a computer interface. Their proposed method, presented in Nature Machine Intelligence, merges the use of an imaging technique and machine learning.
Alexandre Défossez et al, Decoding speech perception from non-invasive brain recordings, Nature Machine Intelligence (2023). DOI: 10.1038/s42256-023-00714-5.
Nov 29, 2023
Dr. Krishna Kumari Challa
Scientists discover rare six-planet system that moves in strange synchrony
Scientists have discovered a rare sight in a nearby star system: Six planets orbiting their central star in a rhythmic beat. The planets move in an orbital waltz that repeats itself so precisely that it can be readily set to music.
A rare case of an "in sync" gravitational lockstep, the system could offer deep insight into planet formationand evolution.
The analysis, led by UChicago scientist Rafael Luque, was published Nov. 29 in Nature.
The six planets orbit a star known as HD110067, which lies around 100 light-years away in the northern constellation of Coma Berenices.
In 2020, NASA's Transiting Exoplanet Survey Satellite (TESS) detected dips in the star's brightness that indicated planets were passing in front of the star's surface. Combining data from both TESS and the European Space Agency's CHaracterizing ExOPlanet Satellite (Cheops), a team of researchers analyzed the data and discovered a first-of-its-kind configuration.
While multi-planet systems are common in our galaxy, those in a tight gravitational formation known as "resonance" are observed by astronomers far less often.
In this case, the planet closest to the star makes three orbits for every two of the next planet out—called a 3/2 resonance—a pattern that is repeated among the four closest planets. Among the outermost planets, a pattern of four orbits for every three of the next planet out (a 4/3 resonance) is repeated twice.
And these resonant orbits are rock-solid: The planets likely have been performing this same rhythmic dance since the system formed billions of years ago, the scientists said.
Orbitally resonant systems are extremely important to find because they tell astronomers about the formation and subsequent evolution of the planetary system. Planets around stars tend to form in resonance but can be easily perturbed. For example, a very massive planet, a close encounter with a passing star, or a giant impact event can all disrupt the careful balance.
As a result, many of the multi-planet systems known to astronomers are not in resonance but look close enough that they could have been resonant once. However, multi-planet systems preserving their resonance are rare.
Rafael Luque, A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067, Nature (2023). DOI: 10.1038/s41586-023-06692-3. www.nature.com/articles/s41586-023-06692-3
Nov 30, 2023
Dr. Krishna Kumari Challa
Nanodiamonds can block tumor metastasis in mice, study shows
Nanodiamonds are 2–8 nm carbon nanoparticles, which can be easily functionalized with various chemical groups like carboxylic groups or drugs. Previous research has shown that actively dividing cells are more likely to absorb nanodiamonds and that epithelial cells treated with carboxylic nanodiamonds lose the ability to migrate across cell-permeable cellulose membranes.
Researchers explored whether nanodiamonds might block tumor metastasis, a process that requires cell migration to new areas. The research is published in the journal PNAS Nexus.
The authors treated B16F10 melanoma cells with carboxylic nanodiamonds in culture and tested their ability to migrate and invade across polycarbonate membranes with 8-µm pores. The authors found that the nanodiamonds blocked the ability of melanoma cells to migrate, while untreated tumor cells were able to pass through the membrane.
Based on gene expression evidence, the authors hypothesize that the tiny carbon nanodiamonds may inhibit the breaking away of cancer cells from the primary tumor mass—as well as block subsequent steps of metastasis such as the physical movement of cells and their ability to enter blood vessels.
According to the authors, nanodiamonds should be further explored as a possible therapeutic agent for cancer metastasis.
Sushreesangita P Behera et al, Carboxyl nanodiamonds inhibit melanoma tumor metastases by blocking cellular motility and invasiveness, PNAS Nexus (2023). DOI: 10.1093/pnasnexus/pgad359
Nov 30, 2023
Dr. Krishna Kumari Challa
Reducing fatal bird collisions
Nov 30, 2023
Dr. Krishna Kumari Challa
A mineral produced by plate tectonics has a global cooling effect, study finds
Geologists have found that a clay mineral on the seafloor, called smectite, has a surprisingly powerful ability to sequester carbon over millions of years.
Under a microscope, a single grain of the clay resembles the folds of an accordion. These folds are known to be effective traps for organic carbon.
Now, the researchers have shown that the carbon-trapping clays are a product of plate tectonics: When oceanic crust crushes against a continental plate, it can bring rocks to the surface that, over time, can weather into minerals including smectite. Eventually, the clay sediment settles back in the ocean, where the minerals trap bits of dead organisms in their microscopic folds. This keeps the organic carbon from being consumed by microbes and expelled back into the atmosphere as carbon dioxide.
Over millions of years, smectite can have a global effect, helping to cool the entire planet. Through a series of analyses, the researchers showed that smectite was likely produced after several major tectonic events over the last 500 million years. During each tectonic event, the clays trapped enough carbon to cool the Earth and induce the subsequent ice age.
The findings are the first to show that plate tectonics can trigger ice ages through the production of carbon-trapping smectite.
"Palaeozoic cooling modulated by ophiolite weathering through organic carbon preservation", Nature Geoscience (2023). DOI: 10.1038/s41561-023-01342-9
Dec 1, 2023
Dr. Krishna Kumari Challa
Brain waves usually found in sleep can protect against epileptic activity
Slow waves that usually only occur in the brain during sleep are also present during wakefulness in people with epilepsy and may protect against increased brain excitability associated with the condition, finds a new study by researchers.
The researchers examined electroencephalogram (EEG) scans from electrodes in the brains of 25 patients with focal epilepsy (a type of epilepsy characterized by seizures arising from a specific part of the brain), while they carried out an associative memory task.
The electrodes had been placed in the patients' brains to localize abnormal activity and inform surgical treatment.
During the task, participants were presented with 27 pairs of images that remained on a screen for six seconds. The images were in nine groups of three—each group featuring a picture of a person, a place and an object. In each case, participants had to remember which images had been grouped together. EEG data were recorded continuously throughout the task.
After reviewing the EEG data, the team found that the brains of people with epilepsy were producing slow waves—lasting less than one second—while they were awake and taking part in the task.
The occurrence of these "wake" slow waves increased in line with increases in brain excitability and decreased the impact of epileptic spikes on brain activity.
In particular, there was a decrease in the "firing" of nerve cells, which the researchers say could protect against epileptic activity.
Wake slow waves in focal human epilepsy impact network activity and cognition, Nature Communications (2023). DOI: 10.1038/s41467-023-42971-3
Dec 1, 2023
Dr. Krishna Kumari Challa
As dengue expands beyond the global 'dengue belt,' scientists dispel conventional wisdom about the disease
Unknowns, dangers and surprises persist about dengue viral infection and now an assumption once accepted as conventional wisdom about immunity to the mosquito-borne disease may be incorrect.
Dengue is a devastating viral infection transmitted to humans through the bite of Aedes aegypti mosquitoes—flying hypodermic needles that descend prolifically during significant outbreaks. Many dengue epidemics tend to occur in urban settings, scientists say. Dengue viral infection can cause a severe headache, high fever, nausea, vomiting, swollen glands, and rash. Still, and perhaps most surprisingly, many people who are infected have no symptoms at all. In rare cases, however, dengue disease can be fatal.
New research involving epidemiological models and data from more than 4,400 people in Nicaragua suggests that it's time immunologists developed a new framework to understand population immunity to dengue. For decades, it was believed that once you were infected with dengue virus, the immunity lasted for life. The dogma persisted in the face of observational data, which found that people who were previously infected were more susceptible to severe dengue if infected again.
But an international collaborative group of researchers has now conclusively shown that immunity not only wanes, it tends to wax and wane—a discovery that reveals dengue infection to be far more complex than previously thought.
According to them, Infection with multiple dengue virus serotypes is thought to induce enduring protection against dengue disease. However, long-term antibody waning has been observed after repeated dengue infection. The waning of antibodies inevitably was followed by a boosting of antibodies when the next epidemic came along.
This discovery allowed the construction of a new model that best describes population vulnerability to dengue infection, especially amid the known periodicity—the cyclic nature—of dengue outbreaks.
When it comes to dengue, people are not permanently immune but susceptible to infection, then immune and ultimately susceptible again. Hence, the researchers newly proposed a model: "susceptible-infected-recovered-susceptible."
Rosemary A. Aogo et al, Effects of boosting and waning in highly exposed populations on dengue epidemic dynamics, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.adi1734
Dec 2, 2023
Dr. Krishna Kumari Challa
New research suggests cellular stress in the placenta may be possible cause of preeclampsia
Preeclampsia is a mysterious condition that occurs in about one of 10 pregnancies without any early warning signs. After 20 weeks or more of normal blood pressure during the pregnancy, patients with preeclampsia will begin to experience elevated blood pressure and may also have increased levels of protein in their urine due to hypertension reducing the filtering power of the kidneys. Prolonged hypertension due to preeclampsia can lead to organ damage and life-threatening complications for mothers and fetuses.
There is no cure for the underlying causes of preeclampsia, so physicians focus on managing and monitoring patients' blood pressure to allow for as close to a full-term gestation as possible. With severe disease, pre-term deliveries are necessary.
For those who get it earlier on, it can be terrifying and life-changing, potentially including a long hospital stay before delivery and significant supportive care for the infant in the NICU afterwards.
Now scientists have published results on a study of one of the emerging theories for what causes preeclampsia in Science Advances.
The experiments focus on a particular layer of cells of the placenta called the syncytiotrophoblast (STB), which is a key part of the barrier between the mother and developing fetus. This blockade helps keep a mother's fully formed immune system from reacting to the fetus and potentially responding as if the fetus was a foreign threat such as a viral or bacterial invader.
The barrier also works in reverse to keep the fetus's growing immune system from reacting to its mother's cells and tissues. The study's authors investigated the hypothesis that an abnormal amount of cellular and molecular stresses to the STB can damage the placenta and lead to preeclampsia.
Part 1
Dec 2, 2023
Dr. Krishna Kumari Challa
By comparing "normal" placentas with placentas from pregnancies where patients suffered from preeclampsia, investigators demonstrated that preeclampsia was associated with higher levels of cellular stresses in the STB layer on the placenta. Additionally, the researchers found a hyperactive level of activity of the Gαq protein known to play a role in transmitting signals related to the levels of several hormones present in excessive amounts during preeclampsia.
So, can preeclampsia be prevented? While today the answer is no, MCW scientists now are one step closer with these experimental results. And they are continuing to work as a team to achieve this goal through additional studies.
Megan Opichka et al, Mitochondrial-Targeted Antioxidant Attenuates Preeclampsia-Like Phenotypes Induced by Syncytiotrophoblast-Specific Gαq Signaling, Science Advances (2023). DOI: 10.1126/sciadv.adg8118. www.science.org/doi/10.1126/sciadv.adg8118
Part 2
Dec 2, 2023
Dr. Krishna Kumari Challa
New discovery: Stunning River of Stars Flowing Through Space
A stunning river of stars has been spotted flowing through the intergalactic space in a cluster of galaxies about 300 million light years away.
Such bridges are known as stellar streams; and, at a length of 1.7 million light-years, the newly named Giant Coma Stream is the longest we've ever seen. And that's not all: the faint river is the first of its kind ever seen outside of a galaxy.
https://www.aanda.org/articles/aa/full_html/2023/11/aa46780-23/aa46...
Dec 3, 2023
Dr. Krishna Kumari Challa
Dolphins can detect electrical fields
Two captive bottlenose dolphins (Tursiops truncatus) have now proved to researchers at the University of Rostock and Nuremberg Zoo in Germany that they can reliably sense weak electric fields in the water with their long snouts.
The discovery hints at the possibility that some marine mammals really can sniff out the electric currents of small prey buried in the sand. They might even use the skill to sense Earth's magnetic field.
To date, only one other 'true' placental mammal on Earth has been found to possess electroreceptors. Little more than a decade ago, scientists demonstrated that the common Guiana dolphin (Sotalia guianensis) evolved its own unique system of electroreception – one that is inherently different to fish, amphibians, and monotremes, like platypuses and echidnas.
Experiments now suggest that adult bottlenose dolphins and Guiana dolphins can both do something oddly similar with a line of sensitive pores on their snouts, called vibrissal crypts. These little holes used to hold juvenile whiskers, and they are extremely sensitive.
In experiments, bottlenose dolphins were able to use these ex-whisker pits to sense very weak electric fields as low as 2.4 and 5.5 microvolts per centimeter – a detection threshold that the researchers say is "in the same order of magnitude as those in the platypus" and also similar to Guiana dolphins.
https://journals.biologists.com/jeb/article/226/22/jeb245845/334721...
Dec 3, 2023
Dr. Krishna Kumari Challa
Food Preserving Technique May Have Sparked Human Brain Growth: Researchers
Researchers propose that a taste for fermented morsels may have triggered a surprising jump in the growth rate of our ancestors' brains.
In fact, a shift from a raw diet to one that included food items already partially broken down by microbes may have been a crucial event in our brain's evolution, according to a perspective study by evolutionary neuroscientists.
Human brains have tripled in size over the last two million years of evolution, while human colons have shrunk by an estimated 74 percent, suggesting a reduced need to break down plant-derived food internally.We know the timeline and extent of human brain expansion, but the mechanisms allowing energy to be directed to this expansion are more complex and somewhat debated.
The study authors lay out their "external fermentation hypothesis" which shows our ancestors' metabolic circumstances for selective brain expansion may have been set in motion by moving intestinal fermentation to an external process, perhaps even experimenting with preserved foods not unlike the wine, kimchi, yoghurt, sauerkraut, and other pickles we still eat today.
The human gut microbiome acts like a machine for internal fermentation, which boosts nutrient absorption during digestion. Organic compounds are fermented into alcohol and acids by enzymes, usually produced by the bacteria and yeasts that live in parts of our digestive system such as our colon.
Fermentation is an anaerobic process, meaning it doesn't require oxygen, so similar to the process in our guts, it can occur in a sealed container. The process produces energy in the form of adenosine triphosphate (ATP), which is an essential source of chemical energy that powers our metabolism.
The researchers argue it's possible that culturally passed-down ways of handling or storing food encouraged this function to be externalized.
Externally fermented foods are easier to digest and contain more available nutrients than their raw equivalents. And since there's less for the colon to do if the food is already fermented, the organ's size could reduce over time while still potentially leaving energy available for brain growth.
Part 1
Dec 4, 2023
Dr. Krishna Kumari Challa
The brain sizes of our ancestors, the Australopiths, were similar to those of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). The human lineage's brain expansion accelerated with Homo's emergence and continued through Homo sapiens and Homo neanderthalensis.
How did our ancestors, with brains about the size of chimpanzees, manage to harness the power of external fermentation?
Researchers suggest that hominids with lower cognitive abilities and smaller brains may have adapted to fermentation much earlier than proposed alternative alternative explanations for this gut-to-brain energy redirection, like animal hunting and fire-based cooking.
Fermentation has many advantages associated with cooked foods, such as softer textures, increased caloric content, improved nutrient absorption, and defense against harmful microorganisms.
The researchers emphasize the need for empirical research to support or refute their hypothesis, such as microbiological studies, comparative analyses, and genetic and genomic investigations.
https://www.nature.com/articles/s42003-023-05517-3
Part 2
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Dec 4, 2023
Dr. Krishna Kumari Challa
Brain implants revive cognitive abilities long after traumatic brain injury in clinical trial
A lady in her final semester of college, planning to apply to law school, when she suffered a traumatic brain injury in a car accident. The injury so compromised her ability to focus she struggled in a job sorting mail.
She couldn't remember anything . Her left foot dropped, so she'd trip over things all the time. She was always in car accidents. And she had no filter—she'd get pissed off really easily.
Her parents learned about research being conducted at Stanford Medicine and reached out; she was accepted as a participant. In 2018, physicians surgically implanted a device deep inside her brain, then carefully calibrated the device's electrical activity to stimulate the networks the injury had subdued. The results of the clinical trial were published Dec. 4 in Nature Medicine. She noticed the difference immediately. When she was asked to list items in the produce aisle of a grocery store, she could rattle off fruits and vegetables. Then a researcher turned the device off, and she couldn't name any. Since the implant she hadn't had any speeding tickets she said. She doesn't trip anymore. She can remember how much money is in her bank account. She wasn't able to read earlier, but after the implant she bought a book, 'Where the Crawdads Sing,' and loved it and remembered it. And she doesn't have that quick temper." For her and four others, the experimental deep-brain-stimulation device restored, to different degrees, the cognitive abilities they had lost to brain injuries years before. The new technique, developed by Stanford Medicine researchers and collaborators from other institutions, is the first to show promise against the long-lasting impairments from moderate to severe traumatic brain injuries.
Nicholas Schiff, Thalamic deep brain stimulation in traumatic brain injury: a phase 1, randomized feasibility study, Nature Medicine (2023). DOI: 10.1038/s41591-023-02638-4. www.nature.com/articles/s41591-023-02638-4
Dec 5, 2023
Dr. Krishna Kumari Challa
Toxic chemicals in whales and dolphins are exceeding safe limits
Almost half of marine mammals around the UK are being poisoned by banned chemicals.
The compounds, once used in pesticides, flame retardants and coolants, are having significant impacts on the health and reproduction of the animals.
The UK's whales and dolphins are full of toxins—and it might only get worse.
Despite many being banned almost 20 years ago, levels of persistent organic pollutants (POPs) remain high in the oceans. In fact, these chemicals may breach safe limits in as many as half of all marine mammals living around the UK, based on a new study of stranded animals.
While the researchers found that levels of six key POPs are declining, they're concerned that the chemicals currently contained in coastal landfill sites could increasingly leak out as flooding, extreme weather and coastal erosion are enhanced by climate change.
What is alarming is this can happen anywhere in the world.
Rosie S. Williams et al, Spatiotemporal Trends Spanning Three Decades Show Toxic Levels of Chemical Contaminants in Marine Mammals, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c01881
Dec 5, 2023
Dr. Krishna Kumari Challa
Why this is so cool: Although scientists have previously extracted ancient DNA, or aDNA, from bones and lake sediments, they hadn't used existing techniques on clay bricks because the brick-baking process usually destroys biological material. The team also accurately dated this particular brick to within several decades (883–859 B.C.E.), thanks to an inscription on its side: “The property of the palace of Ashurnasirpal, king of Assyria.” The brick also listed the king in genealogical order, so the researchers could cross-check that against a list of known rulers from the time.
Dec 5, 2023
Dr. Krishna Kumari Challa
Cracked Piece of Metal Heals Itself in Experiment
Scientists observed a metal healing itself, something never seen before. If this process can be fully understood and controlled, we could be at the start of a whole new era of engineering.
In a study published in July, a research team was testing the resilience of the metal, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times every second. They then observed the self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum. Cracks caused by the kind of strain described above are known as fatigue damage: repeated stress and motion that causes microscopic breaks, eventually causing machines or structures to break. Amazingly, after about 40 minutes of observation, the crack in the platinum started to fuse back together and mend itself before starting again in a different direction.
https://www.nature.com/articles/s41586-023-06223-0
Dec 5, 2023
Dr. Krishna Kumari Challa
Eye scans can provide crucial insights into kidney health, study finds
3D eye scans can reveal vital clues about kidney health that could help to track the progression of disease, research suggests. The advance could revolutionize the monitoring of kidney disease, which often progresses without symptoms in the early stages.
Experts say the technology has the potential to support early diagnosis as current screening tests cannot detect the condition until half of the kidney function has been lost. Researchers used highly magnified images to detect changes to the retina—the layer of tissue at the back of the eye that senses light and sends signals to the brain. They found that the images offer a quick, non-invasive way to monitor kidney health.
The eye is the only part of the body where it is possible to view a key process called microvascular circulation—and this flow of blood through the body's tiniest vessels is often affected in kidney disease.
investigated whether 3D images of the retina, taken using a technology called optical coherence tomography (OCT), could be used to identify and accurately predict the progression of kidney disease.
OCT scanners—used in most high street opticians—use light waves to create a cross-sectional picture of the retina, displaying each individual layer, within a few minutes.
The team looked at OCT images from 204 patients at different stages of kidney disease, including transplant patients alongside 86 healthy volunteers. They found that patients with chronic kidney disease had thinner retinas compared with healthy volunteers. The study also showed that thinning of the retina progressed as kidney function declined.
These changes were reversed when kidney function was restored following a successful transplant. Patients with the most severe form of the disease, who received a kidney transplant, experienced rapid thickening of their retinas after surgery.
This knowledge can be utilized in the future to identify the kidney ailments fast.
Neeraj Dhaun et al, Choroidal & retinal thinning in chronic kidney disease are modifiable with treatment & independently associate with eGFR decline, Nature Communications (2023). www.nature.com/articles/s41467-023-43125-1
Dec 6, 2023
Dr. Krishna Kumari Challa
Harvesting water from air with solar power
More than 2.2 billion people currently live in water-stressed countries, and the United Nations estimates that 3.5 million die every year from water-related diseases. Because the areas most in need of improved drinking water are also located in some of the sunniest places in the world, there is strong interest in harnessing sunlight to help obtain clean water.
Researchers developed a promising new solar-powered atmospheric water harvesting technology that could help provide enough drinking water for people to survive in those difficult, dryland areas.
Historically, researchers have faced challenges when injecting salt into hydrogels as the higher salt content reduced the swelling capacity of the hydrogel due to the salting-out effect. This led to salt leakage and the water absorption capacity decreased.
The researchers synthesized a super hygroscopic gel using plant derivatives and hygroscopic salts that was capable of absorbing and retaining an unparalleled amount of water. One kilogram of dry gel could adsorb 1.18 kilograms of water in arid atmospheric environments and up to 6.4 kilograms in humid atmospheric environments. This hygroscopic gel was simple and inexpensive to prepare and would consequently be suitable for large-scale preparation.
In addition, the team adopted a prototype with desorption and condensation chambers, configured in parallel. They employed a turbofan in the condensation chamber to increase the recovery of desorbed water to more than 90%.
In an outdoor prototype demonstration, the team found it released adsorbed water even in the morning or afternoon when the sun is weak. The system could also achieve simultaneous adsorption and desorption during the daytime.
The team is trying to work to achieve simultaneous adsorption and desorption using renewable energy to maximize daily water yield per unit mass of adsorbent to further optimize the system's performance for practical applications in water generation.
Chengjie Xiang et al, Daytime air-water harvesting based on super hygroscopic porous gels with simultaneous adsorption-desorption, Applied Physics Reviews (2023). DOI: 10.1063/5.0160682
Dec 6, 2023
Dr. Krishna Kumari Challa
Replacing bone saws with smart lasers
Even back in 1957, when Gordon Gould coined the term "laser" (short for "Light Amplification by Stimulated Emission of Radiation"), he was already imagining the possibilities for its use in medicine. Surgeons would be able to make precise incisions without even touching the patient.
Before that could happen, however, there were—and still are—many hurdles to overcome. Manually controlled light sources have been superseded by mechanical and computer-controlled systems to reduce injuries caused by clumsy handling. Switching from continuous beams to pulsed lasers, which turn themselves rapidly on and off, has reduced the heat they produce. Technical advances allowed lasers to enter the world of ophthalmology in the early 1990s. Since then, the technology has moved on in other areas of medicine, too, but only in relatively few applications has it replaced the scalpel and the bone saw.
Safety concerns are the most important hurdle: how can we prevent injury to the surrounding tissue? How closely can the cutting depth be controlled so that deeper layers of tissue are not accidentally damaged?
Researchers have just made an important contribution to the safe and precise use of lasers with their recent publication in the journal Lasers in Surgery and Medicine. They developed a system that combines three functions: it cuts bone, controls the cutting depth and differentiates between different tissues.
These three functions are carried out by three lasers that are aligned to focus on the same spot. The first laser serves as a tissue sensor in that it scans the surroundings of the site where the bone is to be cut.
Pulses are sent with this laser to the surface at regular intervals, so to speak, vaporizing a tiny bit of tissue each time. The composition of this vaporized tissue is measured with a spectrometer. Each type of tissue has its own individual spectrum—its own signature. An algorithm processes this data and creates a kind of map that shows where the bones are located and where the soft tissue is.
Not until all of this has been completed does the second laser, which cuts bone, activate, and then only in places where bones rather than soft tissue are shown on the map that has just been generated. At the same time, the third laser—an optical system—measures the depth of the cut and checks that the cutting laser is not penetrating more deeply than planned. During the cutting phase, the tissue sensor also constantly monitors whether the correct tissue is being cut.
The special thing about this system is that it controls itself—without human interference.
The researchers have so far been testing their system on femur bones and tissue from pigs acquired from a local butcher. They were able to prove that their system works accurately down to fractions of a millimeter. The speed of the combined laser also approaches that of a conventional surgical procedure.
The research team is currently working on making the system smaller.
Arsham Hamidi et al, Multimodal feedback systems for smart laser osteotomy: Depth control and tissue differentiation, Lasers in Surgery and Medicine (2023). DOI: 10.1002/lsm.23732 Arsham Hamidi et al,
Towards miniaturized OCT-guided laser osteotomy: integration of fiber-coupled Er:YAG laser with OCT, Optics Continuum (2023). DOI: 10.1364/OPTCON.497483
Dec 6, 2023
Dr. Krishna Kumari Challa
Scientist Rebellion is composed of thousands of climate researchers, academics, and concerned citizens who are urging people to get involved in the effort to limit global overheating. As part of the COP 28 proceedings, Scientist Rebellion is urging people to sign an open letter pleading for governments to heed the climate science and take meaningful action while there is still time.
https://scientistrebellion.org/
https://cleantechnica.com/2023/12/05/1000-scientists-plead-for-publ...
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The first ever 1,000-qubit quantum chip
IBM has unveiled the first quantum computer with 1,121 superconducting qubits (qubits are the quantum equivalent of digital bits in a classical computer). Quantum computers could outperform classical computers in certain areas by exploiting phenomena such as entanglement and superposition. However, these quantum states are notoriously fickle and prone to error, so simply having more qubits does not necessarily make a system better. IBM says it will now focus on more error-resistant systems, rather than larger ones.
https://www.nature.com/articles/d41586-023-03854-1?utm_source=Live+...
Dec 6, 2023
Dr. Krishna Kumari Challa
Earliest mosquito was a bloodsucking male
The discovery of the earliest known fossil mosquitoes, preserved in Lebanese amber, had a sting in the tail: the insects were bloodsucking males. Today, only female mosquitoes eat blood, with males living on nectar and plant juices. The 125-million-year-old fossils have mouthparts that look perfect for piercing skin, as well as mate-grabbing appendages that confirm their sex. The finding could turn current thinking — that blood-sucking evolved after plant-eating — on its head. “We think now that, originally, the mosquito could be bloodsucking,” says palaeontologist and study co-author Dany Azar. “With the appearance of the flowering plant, this function could be just forgotten later on.”
https://www.sciencedirect.com/science/article/pii/S0960982223014483...
Dec 6, 2023
Dr. Krishna Kumari Challa
Is Dementia contagious?
Could Blood Transfusions and Tissue Transplants Spread Certain Dementias?
Scattered evidence suggests that aberrant proteins act as “seeds” to transmit neurodegenerative disease, but the jury is still out
In the last several years, scientists have begun investigating whether neurodegenerative diseases like Alzheimer’s and Parkinsons can be contagious. One misfolded protein, scientists hypothesize, might somehow ensnare other proteins and cause them to misfold, leading to plaque build-up in the brain. If a malfunctioning protein somehow finds its way into another individual, could it launch a similar accumulation of proteins?
What they've found: In 2015 researchers reported a curious buildup of the protein plaque associated with some dementias in young to middle-age adults who had received childhood injections of human growth hormone extracted from the pituitary glands of cadavers. And in 2018 doctors recorded unusual cases of cerebral amyloid angiopathy, a condition marked by amyloid buildup in cerebral blood vessels; because these young adults had brain surgery in childhood, the researchers suspect that contaminated surgical tools transferred the “seeds” of plaque accumulation to the patients’ brains.
Why this matters: Learning how prionlike diseases “spread” might launch treatments that interrupt their replication and accumulation. Early studies in mice have shown that amyloid antibodies can clear plaque build up, which aligns with recent trials of new Alzheimer’s treatments that show how removing brain amyloid can slow cognitive decline. If protein misfolding is contagious, we may have a new way to interrupt the devastation it causes.
https://www.scientificamerican.com/article/could-blood-transfusions...
Dec 6, 2023
Dr. Krishna Kumari Challa
Research shows mouse and primate brains mature at same pace
A new study has revealed that short-lived mice and longer-living primates develop brain synapses on the exact same timeline, challenging assumptions about disease and aging. What does this mean for humans—and yesterday's research?
Mice typically live two years and monkeys live 25 years, but the brains of both appear to develop their synapses at the same time. This finding, the result of a recent study has puzzled neuroscientists.
Until now, brain development was understood as happening faster in mice than in other, longer-living mammals such as primates and humans. Those studying the brain of a 2-month-old mouse, for example, assumed the brain was already finished developing because it had a shorter overall lifespan in which to develop. In contrast, the brain of a 2-month-old primate was still considered going through developmental changes. Accordingly, the 2-month-old mouse brain was not considered a good comparison model to that of a 2-month-old primate. That assumption appears to be completely wrong, which the authors think will call into question many results using young mouse brain data as the basis for research into various human conditions, including autism and other neurodevelopmental disorders.
Gregg Wildenberg et al, Isochronic development of cortical synapses in primates and mice, Nature Communications (2023). DOI: 10.1038/s41467-023-43088-3
Dec 7, 2023
Dr. Krishna Kumari Challa
New study concludes finding cure for malaria may be even more challenging than thought
Researchers who have studied malaria for decades, hoping to find a cure, long thought they'd identified a type of blood that seemed to defend against the disease. But a new study published in Cell Host & Microbe concludes that even some people with the protective blood type became infected. The question now is, how? "This might mean that the specific gene mutation related to this blood type doesn't completely stop malaria, or the malaria bug might have found another way to get into the blood cells," said Peter Zimmerman, a pathology professor at Case Western Reserve University School of Medicine and the study's senior author. "It's a big deal because it might change how we try to get rid of this type of malaria parasite." "This malaria parasite, called Plasmodium vivax—or P. vivax—used to be common in Northeast Ohio," said Christopher King, a study co-investigator and pathology professor. "And it was transmitted within the United States—Florida and Texas—this summer for the first time in 20 years.
"We have known," King said, "that the United States is at risk of re-introduction of malaria with climate changes and increasing immigration and traveling from malaria-endemic areas."Study collaborators include researchers from France (Célia Dechavanne and Benoit Gamain, from the National Institute of Blood Transfusion, INSERM/Paris Diderot University); and Madagascar (Arsène Ratsimbasoa, from the University of Fianarantsoa).
Part 1
Dec 7, 2023
Dr. Krishna Kumari Challa
"Malaria researchers have been trying to chip away at understanding resistance and susceptibility of P. vivax infection of African people for more than 100 years," Zimmerman said. "More than 2.5 billion people may live in Africa and Southeast Asia where the parasite is found. Hundreds of thousands of people a year die from malaria. In general, malaria is one of the big three global-health infectious diseases—malaria, tuberculous and HIV/AIDS."
The team is studying a specific blood type (Fy-negative) in the blood of most people in Africa and of African origin, called "the silent Duffy blood group." Duffy-negative people have a mutation in the DNA code (GATA-1) that results in the protein not being expressed on the surface of red blood cells.
The researchers did experiments using blood cells grown in the lab and cells taken from bone marrow to study the Duffy-silent blood type.
"Surprisingly, we found that even when people are missing the GATA-1 DNA code, the Duffy protein sometimes shows up on their red blood cells," Zimmerman said. "Our findings suggest that the bone marrow and other places where blood cells are first made are important for the malaria parasite to find the red cells with the Duffy protein, to grow and cause sickness."
In other experiments in the lab, they examined the blood of people with Duffy silent blood type. They noticed the P. vivax malaria infection was often detected using a special test rather than the usual microscope test.
This means that people with Duffy-silent blood type can still have the infection, but it's not always easy to see in regular blood tests. In other words, they found that P. vivax can invade the red blood cells of people with the Duffy-silent trait. Also, if they have the infection in the bone marrow, they produce the transmissible form of the parasite. Mosquitoes can acquire it and cause infections in other people.
"This discovery raises questions about how malaria parasites cause infection and sickness, especially because some people with the infection don't show many signs in their blood," Zimmerman said. "We need to look at the blood more closely to understand better how widespread and serious this type of malaria is in people with the Duffy-silent trait."
Celia Dechavanne et al, Duffy antigen is expressed during erythropoiesis in Duffy-negative individuals, Cell Host & Microbe (2023). DOI: 10.1016/j.chom.2023.10.019
Part 2
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Dec 7, 2023
Dr. Krishna Kumari Challa
Study finds sleep can improve memory retention but can also imprint false memories
A team of psychologists has found via experimentation that sleeping after studying can consolidate memories. But, as they note in their paper published in the journal Royal Society Open Science, sleep can also sometimes lead to the creation of false memories.
Recent research efforts have shown that human memory is not nearly as accurate as it may feel to someone who is recalling a memory of a thing or event—findings that have called into question eyewitness accounts at criminal trials. Such results have led to more study of memory retention and recall as a way to learn more about the ways that memory works.
For this new research, 488 volunteers studied a list of related words and then to attempt to recall those words 12 hours later. To learn about the impact of sleep on retention, some of the volunteers were allowed to sleep between the time they viewed the original list and the time of the memory retention testing.
The researchers found that those people who were allowed to sleep during the interim scored better on memory retention. But they also found that they were more likely to believe falsely that some related words were on the list. As an example, when given a list such as "nurse, hospital and surgery," people who had been allowed to sleep were more likely to falsely believe the word "doctor" had also appeared on the list.
The researchers suggest this finding shows that the purpose of memory is not necessarily to give people an accurate assessment of things that have occurred, but to give them a means for retrieving the gist of things. As humans evolved, it was important that connections and associations be made as part of the learning process in order to better prepare for future threats.
The research team also found that the time of day the volunteers were questioned about the list had an impact on recall accuracy—both groups made more errors and falsely recalled more words when questioned during the evening.
Matthew H. C. Mak et al, A registered report testing the effect of sleep on Deese-Roediger-McDermott false memory: greater lure and veridical recall but fewer intrusions after sleep, Royal Society Open Science (2023). DOI: 10.1098/rsos.220595
Dec 7, 2023
Dr. Krishna Kumari Challa
A possible way for early life on Earth to survive cosmic radiation
A team of biophysicists has uncovered via experimentation the means by which early life might have been able to survive cosmic radiation. In their study, reported in the journal Nature Communications, the group conducted experiments with radiation-resistant manganese antioxidants.
Prior research has shown that the Earth was formed approximately 4.5 billion years ago, and that life arose approximately a half-billion years later. Prior research has also shown that the Earth's magnetic field did not start protecting life from cosmic radiation until approximately 3.5 billion years ago. This leads to questions about how life was able to begin and flourish in those early years.
A type of bacteria known as Deinococcus radiodurans has been shown to be capable of surviving levels of radiation that would kill most other living creatures. Study of this bacteria reveals that it is able to do so because of the amount of Mn(II) (manganese) ions in its body—it serves to protect the tiny creatures from the oxidative stress that would occur in other bacteria that do not have it. This finding has led to theories that suggest harboring of Mn(II) ions is the means by which early life survived on Earth.
To test this theory, the research team created models they describe as protocells—such "coacervates" were used to serve as stand-ins for early life protocells on Earth. The team used two types, one based on polyphosphate manganese, the other based on polyphosphate peptides. When exposed to high levels of gamma rays, the polyphosphate–manganese coacervates remained intact and viable. The polyphosphate–peptide coacervates, on the other hand, were destroyed. Prior research has shown that polyphosphate manganese has been present on Earth longer than life has existed, likely produced during volcanic activity—thus, it would have been available for use by protocells as a means of protection. The researchers suggest that early protocells on Earth were able to survive due to protection by material similar to polyphosphate manganese. Such protocells, they note, would have been able to survive long enough to develop into cyanobacteria and eventually eukaryotic cells, which would have been protected by the Earth's magnetic field and ozone layer.
Shang Dai et al, An inorganic mineral-based protocell with prebiotic radiation fitness, Nature Communications (2023). DOI: 10.1038/s41467-023-43272-5
Dec 7, 2023
Dr. Krishna Kumari Challa
Plant Hormone That Can Boost Plant Growth By 30%
Dec 7, 2023
Dr. Krishna Kumari Challa
Researchers show that an influx of water and salts propel immune cells through the body
Researchers have shown that an influx of water and ions into immune cells allows them to migrate to where they're needed in the body.
Our bodies respond to illness by sending out chemical signals called chemokines, which tell immune cells called T cells where to go to fight the infection. This process had already been associated with a protein called WNK1, which activates channels on the cell surface, allowing ions (salts like sodium or potassium) to move into cells. Until now, it was not clear why ion influx was needed for T cells to move.
Through a study published in Nature Communications, the researchers imaged mouse T cells and observed that, following a chemokine signal, WNK1 is activated at the front of the cells, called the "leading edge." The team showed that the activation of WNK1 opens channels on the leading edge, resulting in an influx of water and ions. They propose that this flow of water causes the cells to swell on the front side, creating space for the 'actin cytoskeleton'—the scaffolding inside the cell that holds its structure—to grow into. This propels the whole cell forward and the process repeats again. The researchers used gene editing to stop mice producing WNK1, or an inhibitor to prevent WNK1's activity, observing that the T cells in these mice slowed down or stopped moving completely. Importantly, they found that they could make up for the loss of WNK1 and make the cells speed up by dropping them into a watery solution, which causes the cells to take up water and swell. This shows that the uptake of water, controlled by the WNK1 protein is key for the cells to migrate.
The researchers think that the mechanism they've discovered could be involved in lots of different cell types beyond immune cells.
Leonard L. de Boer et al, T cell migration requires ion and water influx to regulate actin polymerization, Nature Communications (2023). DOI: 10.1038/s41467-023-43423-8
Dec 7, 2023
Dr. Krishna Kumari Challa
Study finds climate change can cause methane to be released from the deep ocean
New research has shown that fire-ice—frozen methane which is trapped as a solid under our oceans—is vulnerable to melting due to climate change and could be released into the sea.
An international team of researchers found that as frozen methane and ice melts, methane—a potent greenhouse gas—is released and moves from the deepest parts of the continental slope to the edge of the underwater shelf. They even discovered a pocket that had moved 25 miles (40 kilometers). Publishing in the journal Nature Geoscience, the researchers say this means that much more methane could potentially be vulnerable and released into the atmosphere as a result of climate warming.
Methane hydrate, also known as fire-ice, is an ice-like structure found buried in the ocean floor that contains methane. Vast amounts of methane are stored as marine methane under oceans. It thaws when the oceans warm, releasing methane into oceans and the atmosphere—known as dissociated methane—contributing to global warming.
The scientists used advanced three-dimensional seismic imaging techniques to examine the portion of the hydrate that dissociated during climatic warming off the coast of Mauritania in Northwest Africa. They identified a specific case where dissociated methane migrated over 40 kilometers and was released through a field of underwater depressions, known as pockmarks, during past warm periods.
Long-distance migration and venting of methane after marine hydrate dissociation, Nature Geoscience (2023). DOI: 10.1038/s41561-023-01333-w. www.nature.com/articles/s41561-023-01333-w
Dec 7, 2023
Dr. Krishna Kumari Challa
Planet tipping points pose 'unprecedented' threat to humanity: report
Humanity faces an "unprecedented" risk from tipping points that could unleash a domino effect of irreversible catastrophes across the planet, researchers warned this week.
The most comprehensive assessment ever conducted of Earth's invisible tripwires was released as leaders meet for UN climate talks in Dubai with 2023 set to smash all heat records. While many of the 26 tipping points laid out in the report—such as melting ice sheets—are linked to global warming, other human activities like razing swathes of the Amazon rainforest could also push Earth's ecosystems to the brink. Five of these are showing signs of tipping—from melting ice sheets threatening catastrophic sea level rise, to mass die-off of tropical coral reefs—the report warned. Some may have already begun to irrecoverably transform. Once the world crosses the threshold for just one tipping point, dealing with the immediate humanitarian disaster could distract attention away from stopping the others, creating a "vicious cycle" of mass hunger, displacement and conflict, the report warned.
The risks for humanity in crossing tipping points into these unexplored states is dire, and the impact to human lives potentially horrific.
Source: News agencies
Dec 7, 2023
Dr. Krishna Kumari Challa
Warfare ruins the environment—and not just on the front lines
On the morning of December 6, 1917, a French cargo ship called SS Mont-Blanc collided with a Norwegian vessel in the harbor of Halifax in Nova Scotia, Canada. The SS Mont-Blanc, which was laden with 3,000 tons of high explosives destined for the battlefields of the first world war, caught fire and exploded. The resulting blast released an amount of energy equivalent to roughly 2.9 kilotons of TNT, destroying a large part of the city. Although it was far from the front lines, this explosion left a lasting imprint on Halifax in a way that many regions experience environmental change as a result of war. The attention of the media is often drawn to the destructive explosions caused by bombs, drones or missiles. And the devastation we have witnessed in cities like Aleppo, Mosul, Mariupol and now Gaza certainly serve as stark reminders of the horrific impacts of military action. However, research is increasingly uncovering broader and longer-term consequences of war that extend well beyond the battlefield. Armed conflicts leave a lasting trail of environmental damage, posing challenges for restoration after the hostilities have eased.
https://theconversation.com/warfare-ruins-the-environment-and-not-j...
Dec 7, 2023
Dr. Krishna Kumari Challa
Ancient stars made extraordinarily heavy elements, researchers find
How heavy can an element be? An international team of researchers has found that ancient stars were capable of producing elements with atomic masses greater than 260, heavier than any element on the periodic table found naturally on Earth. The finding deepens our understanding of element formation in stars.
We are, literally, made of star stuff. Stars are element factories, where elements constantly fuse or break apart to create other lighter or heavier elements. When we refer to light or heavy elements, we're talking about their atomic mass. Broadly speaking, atomic mass is based on the number of protons and neutrons in the nucleus of one atom of that element.
The heaviest elements are only known to be created in neutron stars via the rapid neutron capture process, or r-process. Picture a single atomic nucleus floating in a soup of neutrons. Suddenly, a bunch of those neutrons get stuck to the nucleus in a very short time period—usually in less than one second—then undergo some internal neutron-to-proton changes, and voila! A heavy element, such as gold, platinum or uranium, forms.
The heaviest elements are unstable or radioactive, meaning they decay over time. One way that they do this is by splitting, a process called fission.
The r-process is necessary if you want to make elements that are heavier than, say, lead and bismuth.
You have to add many neutrons very quickly, but the catch is that you need a lot of energy and a lot of neutrons to do so. And the best place to find both are at the birth or death of a neutron star, or when neutron stars collide and produce the raw ingredients for the process.
The team took a fresh look at the amounts of heavy elements in 42 well-studied stars in the Milky Way. The stars were known to have heavy elements formed by the r-process in earlier generations of stars. By taking a broader view of the amounts of each heavy element found in these stars collectively, rather than individually as is more common, they identified previously unrecognized patterns.
Part 1
Dec 8, 2023
Dr. Krishna Kumari Challa
Those patterns signaled that some elements listed near the middle of the periodic table—such as silver and rhodium—were likely the remnants of heavy element fission. The team was able to determine that the r-process can produce atoms with an atomic mass of at least 260 before they fission.
That 260 is interesting because we haven't previously detected anything that heavy in space or naturally on Earth, even in nuclear weapon tests.
Ian U. Roederer et al, Element abundance patterns in stars indicate fission of nuclei heavier than uranium, Science (2023). DOI: 10.1126/science.adf1341. www.science.org/doi/10.1126/science.adf1341
Part 2
Dec 8, 2023
Dr. Krishna Kumari Challa
Physicists 'entangle' individual molecules for the first time, hastening possibilities for quantum computing
For the first time, a team of physicists have been able to link together individual molecules into special states that are quantum mechanically "entangled." In these bizarre states, the molecules remain correlated with each other—and can interact simultaneously—even if they are miles apart, or indeed, even if they occupy opposite ends of the universe. This research was recently published in the journal Science.
This is a breakthrough in the world of molecules because of the fundamental importance of quantum entanglement. And it is also a breakthrough for practical applications because entangled molecules can be the building blocks for many future applications.
These include, for example, quantum computers that can solve certain problems much faster than conventional computers, quantum simulators that can model complex materials whose behaviors are difficult to model, and quantum sensors that can measure faster than their traditional counterparts.
To entangle the molecules, they had to make the molecule interact. By using a series of microwave pulses, they were able to make individual molecules interact with one another in a coherent fashion.
By allowing the interaction to proceed for a precise amount of time, they were able to implement a two-qubit gate that entangled two molecules. This is significant because such an entangling two-qubit gate is a building block for both universal digital quantum computing and for simulation of complex materials.
Connor M. Holland et al, On-demand entanglement of molecules in a reconfigurable optical tweezer array, Science (2023). DOI: 10.1126/science.adf4272. www.science.org/doi/10.1126/science.adf4272
Yicheng Bao et al, Dipolar spin-exchange and entanglement between molecules in an optical tweezer array, Science (2023). DOI: 10.1126/science.adf8999. www.science.org/doi/10.1126/science.adf8999
Augusto Smerzi et al, Entanglement with tweezed molecules, Science (2023). DOI: 10.1126/science.adl4179. www.science.org/doi/10.1126/science.adl4179
Dec 8, 2023
Dr. Krishna Kumari Challa
Scientists create 'cloaked' donor cell, tissue grafts that escape immune system rejection
Immune rejection poses a major challenge in donor cell therapy. Transplant and cell therapy patients are required to take immunosuppressive drugs – sometimes for the rest of their lives – to prevent their bodies from rejecting the transplant. The extended use of these drugs can lead to serious health issues, including recurring infections and an elevated cancer risk.
Scientists worldwide have been exploring various solutions, including creating therapeutic cells from the patient’s own cells or encapsulating donor cells in inorganic material for protection.
But these methods face challenges such as high costs, long preparation times and foreign body immune response, complicating their widespread and cost-effective application.
Researchers now have developed a technology that may one day eliminate the need for immunosuppressive drugs in transplant patients.
Through genetic modification of donor cells, the researchers successfully created transplants that persisted long-term in pre-clinical testing without the need for immune suppression.
The findings raise hope that a similar strategy could be employed in human patients, potentially making transplantation safer and more widely available.
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Stem cells have the unique ability to divide indefinitely and give rise to specialized cells that form our organs. They make an ideal source for cell therapies as large numbers of cells can be obtained and converted into desired cell types to replace those lost to disease or injury.
But there are major safety concerns: in addition to addressing immune-matching, scientists must ensure that no unwanted dividing cells remain in the transplant that could cause cancer in the future.
Researchers selected eight key genes that regulate how the immune system responds to threats, including foreign cells. Forced overexpression of these genes in mouse embryonic stem cells prevented the immune system from recognizing them as foreign.
The modification effectively created an immune cloak around the cells following their injection under the skin of genetically unmatched hosts.
This study demonstrates the combined potential of FailSafe and immune cloaking for the creation of a universal source of cells that could be applied to a multitude of diseases.
Uncloaked cells are typically rejected within 10 days of transplantation. In contrast, the cloaked cells persisted for more than nine months at the endpoint of the experiment. This is the first time that scientists have been able to achieve this length of time without rejection in a fully functional immune system.
In another key finding, the researchers showed that unmodified cells can escape rejection when embedded into the tissue created by the cloaked donor cells below the skin surface. The protection extended to cells from another species, as shown by the ability of unmodified human cells to survive within a cloaked mouse graft.
This suggests that modified cells also act as an immune-privileged implantation site for unmodified cells, with implications for interspecies transplants. Researchers at other institutions are exploring the potential of pigs as donors because their organs are very similar in size and function to humans.
https://www.nature.com/articles/s41551-023-01133-y
Dec 8, 2023
Dr. Krishna Kumari Challa
Study reveals genes that set humans apart from other primates in cognitive ability
An international team of researchers has uncovered over 100 genes that are common to primate brains but have undergone evolutionary divergence only in humans – and which could be a source of our unique cognitive ability.
They found the genes are expressed differently in the brains of humans compared to four of our relatives – chimpanzees, gorillas, macaques and marmosets.
The findings, published in Nature Ecology & Evolution, suggest that reduced selective pressure, or tolerance to loss-of-function mutations, may have allowed the genes to take on higher-level cognitive capacity. The study is part of the Human Cell Atlas, a global initiative to map all human cells to better understand health and disease.
This research contributes to our understanding of differences in the brain between humans and other primates at the cellular level, but it has also resulted in a database that can be used to further characterize genetic similarities and differences across primates.
In all, the team found 139 genes that are common across the primate groups but highly divergent in their expression in human brains. These genes displayed a stronger ability to withstand mutations without impacting their function, suggesting they may have evolved under more relaxed selective pressure.
The genes that have diverged in humans must be tolerant to change. This manifests as tolerance to loss-of-function mutations, and seems to allow for rapid evolutionary change in the human brain.
Our higher cognitive function may have resulted from the adaptive evolution of human brain cells to a multitude of less threatening mutations over time. It’s also worth noting that around a quarter of the human-divergent genes identified in the study are associated with various brain disorders.
The divergent genes the researchers identified are found in 57 brain cell types, grouped by inhibitory neurons, excitatory neurons and non-neurons. A quarter of the genes were only expressed differently in neuronal cells, also known as grey matter, and half were only expressed differently in glial cells, which are white matter.
Grey matter in the brain consists of neurons, while white matter consists of other cell types, including those responsible for vasculature and immune function.
Hamsini Suresh et al, Comparative single-cell transcriptomic analysis of primate brains highlights human-specific regulatory evolution, Nature Ecology & Evolution (2023). DOI: 10.1038/s41559-023-02186-7
Dec 8, 2023
Dr. Krishna Kumari Challa
Self-copying RNA vaccine wins approval
Japanese regulators have approved a COVID-19 vaccine constructed using a form of RNA that can make copies of itself inside cells. It’s the first ‘self-amplifying’ RNA (saRNA) vaccine platform to be granted full regulatory approval anywhere in the world. Because it could be used at a lower dose, it might have fewer side effects than other messenger RNA (mRNA) treatments have. When used as a booster in clinical testing, the newly authorized vaccine, ARCT-154 — developed by US biotechnology firm Arcturus Therapeutics and Australia-based CSL — triggered higher levels of virus-fighting antibodies that circulated the body for longer than did a standard mRNA COVID-19 vaccine.
https://www.nature.com/articles/d41586-023-03859-w?utm_source=Live+...
Dec 8, 2023
Dr. Krishna Kumari Challa
Electricity from electric eels may transfer genetic material to nearby animals
The electric eel is the biggest power-making creature on Earth. It can release up to 860 volts, which is enough to run a machine. In a recent study, a research group found electric eels can release enough electricity to genetically modify small fish larvae. They published their findings in PeerJ.
The researchers' findings add to what we know about electroporation, a gene delivery technique. Electroporation uses an electric field to create temporary pores in the cell membrane. This lets molecules, like DNA or proteins, enter the target cell.
To test this, they exposed the young fish in their laboratory to a DNA solution with a marker that glowed in the light to see if the zebrafish had taken the DNA. Then, they introduced an electric eel and prompted it to bite a feeder to discharge electricity.
Electroporation might happen in nature. Researchers realized that electric eels in the Amazon River could well act as a power source, organisms living in the surrounding area could act as recipient cells, and environmental DNA fragments released into the water would become foreign genes, causing genetic recombination in the surrounding organisms because of electric discharge.
The researchers discovered that 5% of the larvae had markers showing gene transfer. "This indicates that the discharge from the electric eel promoted gene transfer to the cells, even though eels have different shapes of pulse and unstable voltage compared to machines usually used in electroporation. Electric eels and other organisms that generate electricity could affect genetic modification in nature.
Other studies have observed a similar phenomenon occurring with naturally occurring fields, such as lightning, affecting nematodes and soil bacteria.
Shintaro Sakaki et al, Electric organ discharge from electric eel facilitates DNA transformation into teleost larvae in laboratory conditions, PeerJ (2023). DOI: 10.7717/peerj.16596
Dec 8, 2023
Dr. Krishna Kumari Challa
The zebrafish larvae and a DNA solution were put into a small container and placed inside the tank where the electric eel produces electric pulses when it is fed by the experimenter.
Part 2
Dec 8, 2023
Dr. Krishna Kumari Challa
Six-million-year-old groundwater pool discovered deep under Sicilian mountains
A multi-institutional team of geoscientists has discovered a deep, ancient underground pool of fresh water underneath part of the Sicilian mountains. In their study, reported in the journal Communications Earth & Environment, the group used publicly available data gathered from oil discovery efforts to study the groundwater in and around the Gela formation beneath the mountains on the island of Sicily.
The researchers analyzed maps and data from prior surveys looking for oil deposits. They discovered what they believe to be a previously unknown aquifer thousands of feet below the Hyblaean Mountains. They made 3D models of the aquifer to validate their findings and found evidence suggesting that not only is it an aquifer, but it holds approximately 17.5 cubic kilometers of water.
The team then set out to explain how so much fresh water could have come to reside, locked in, beneath a mountain range. They suggest it was trapped there during the Messinian salinity crisis millions of years ago—the 700,000-year period saw a blockage at the Strait of Gibraltar that allowed many parts of the Mediterranean Sea to dry up, exposing the seafloor to rainwater.
The research team suggests that this rainwater trickled down into the crust. Such rainwater, the researchers note, could have accumulated underground as it was soaked up by carbonate rock acting as a sponge. When sea levels returned to normal, the underground fresh water was locked in due to seawater pressure.
Lorenzo Lipparini et al, Extensive freshened groundwater resources emplaced during the Messinian sea-level drawdown in southern Sicily, Italy, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-01077-w
Dec 9, 2023
Dr. Krishna Kumari Challa
Genetic mutations that promote reproduction tend to shorten human lifespan, study shows
A study based on a review of genetic and health information from more than 276,000 people finds strong support for a decades-old evolutionary theory that sought to explain aging and senescence.
In 1957, evolutionary biologist George Williams proposed that genetic mutations that contribute to aging could be favored by natural selection if they are advantageous early in life in promoting earlier reproduction or the production of more offspring.
Now known as the antagonistic pleiotropy theory of aging, remains the prevailing evolutionary explanation of senescence, the process of becoming old or aging.
This theory was tested now.
The researchers found reproduction and lifespan to be genetically strongly negatively correlated, meaning that genetic mutations that promote reproduction tend to shorten lifespan.
In addition, individuals carrying mutations that predispose them to relatively high reproductive rates have lower probabilities of living to age 76 than those carrying mutations that predispose them to relatively low reproductive rates, according to the study.
However, the authors caution that reproduction and lifespan are affected by both genes and the environment. And compared with environmental factors—including the impacts of contraception and abortion on reproduction and medical advances on lifespan—the genetic factors discussed in the study play a relatively minor role, according to the authors. These results provide strong support for the Williams hypothesis that aging arises as a byproduct of natural selection for earlier and more reproduction. Natural selection cares little about how long we live after the completion of reproduction, because our fitness is largely set by the end of reproduction.
Fitness is a concept biologists use to describe the degree to which an organism's characteristics increase its number of offspring.
The researchers now found that when you control for the genetically predicted amount and timing of reproduction, having two kids corresponds to the longest lifespan. Having fewer or more kids both lower the lifespan. That result supports the findings of several previous studies.
Part 1
Dec 9, 2023
Dr. Krishna Kumari Challa
In genetics, the concept of pleiotropy posits that a single mutation can influence multiple traits. The idea that the same mutation can be both beneficial and harmful, depending on the situation, is known as antagonistic pleiotropy and was proposed by Williams to underlie the origin of aging in a paper titled "Pleiotropy, natural selection, and the evolution of senescence."
To a biologist, senescence refers specifically to a gradual decline of bodily functions that manifests as a decline in reproductive performance and an increase in the death rate with age.
Compared with environmental factors, genetic factors play a minor role in the human phenotypic changes studied here.
Erping Long et al, Evidence for the role of selection for reproductively advantageous alleles in human aging, Science Advances (2023). DOI: 10.1126/sciadv.adh4990. www.science.org/doi/10.1126/sciadv.adh4990
Part 2
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Dec 9, 2023
Dr. Krishna Kumari Challa
Researchers discover a mechanism that controls the identity of stem cells
Researchers discovered a mechanism that controls the identity of stem cells. When this mechanism fails, embryonic stem cells revert back in time and become totipotent (totipotent embryo cells can differentiate into a hundred different cell types specialized to form such tissues as skin, marrow, and muscle).
When a cell becomes totipotent, this rare change enables the cells to differentiate into hundreds of cell types, and then go on to form every part of our body. This contrasts with pluripotent stem cells, which can divide into various cell types but are unable to become an entire organism solely on their own.
In a dish of embryonic stem cells, the majority of stem cells are pluripotent. However, 1 out of 1,000 cells are different from the rest, and are totipotent. Totipotent cells are the only cells that have unlimited potential and can give rise to all parts of our body. Scientists now discovered the mechanism that allows this change from pluripotent to totipotent.
Denis Torre et al, Nuclear RNA catabolism controls endogenous retroviruses, gene expression asymmetry, and dedifferentiation, Molecular Cell (2023). DOI: 10.1016/j.molcel.2023.10.036
Dec 9, 2023
Dr. Krishna Kumari Challa
Credit: Molecular Cell (2023). DOI: 10.1016/j.molcel.2023.10.036
Dec 9, 2023
Dr. Krishna Kumari Challa
Rich nations need to ditch fossil fuels by 2040: scientists
Rich countries need to stop using coal by 2030 and oil and gas by 2040, with poorer nations following a decade behind, to give the world a chance of limiting warming to 1.5C, climate scientists told the UN this week.
In a note to the UN Secretary-General Antonio Guterres and UN Climate Change body, shared with AFP, climate scientists said there was very little room for anything but a total phase-out of fossil fuels.
The steep timeline they laid out comes as climate negotiators at the COP28 talks in Dubai are tussling over the future of oil, gas and coal, responsible for the lion's share of humanity's planet-heating emissions.
The UN climate negotiations are tasked with helping the world meet the Paris deal goal of limiting global warming to 1.5 degrees Celsius from pre-industrial levels, but have often been vague on how that target will be achieved.
The discussions should be around serious and fair efforts to start implementing a phase out plan: scientists
Source: AFP
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Israel's AI can produce 100 bombing targets a day in Gaza. Is this ...
Last week, reports emerged that the Israel Defense Forces (IDF) are using an artificial intelligence (AI) system called Habsora (Hebrew for "The Gospel") to select targets in the war on Hamas in Gaza. The system has reportedly been used to find more targets for bombing, to link locations to Hamas operatives, and to estimate likely numbers of civilian deaths in advance.
https://theconversation.com/israels-ai-can-produce-100-bombing-targ...
Dec 9, 2023