If you've got a dark roof, you're spending almost $700 extra a year to keep your house cool
A dark roof means you'll pay considerably more to keep your house cool in summer.When suburbs are full of dark colored roofs, the whole area heats up. And up. And up. This is part of the urban heat island effect.
Light coloured roofs or Cool roofs have many benefits. They slash how much heat gets into your house from the sun, keep the air surrounding your home cooler, boost your aircon efficiency, and make your solar panels work more efficiently.
At present, the world's cities account for 75% of all energy-related carbon dioxide emissions. It's vitally important we understand what makes cities hotter or cooler.
Brick, concrete, tarmac and tiles can store more heat than grass and tree-covered earth can, and release it slowly over time. This keeps the air warmer, even overnight.
Built-up areas also block wind, which cuts cooling. Then there's transport, manufacturing and air-conditioning, all of which increase heat.
The main way people had to keep cool was through how they designed their homes. In hot countries, buildings are often painted white, as well as having small windows and thick stone walls.
Light roofs, light roads and better tree cover would make a real difference.
If your street has established large trees, you will experience less than half the number of days withextreme heatcompared on residentson treeless streets. If you live in a leafy street, your home is alsoworth more.
Blacktop roads are a surprisingly large source of heat. In summer, they canget up to 75°C. Research shows reflective sealants can cut the temperaturesup to 13°C. Some councilshave experimentedwith lighter roads, but to date, uptake has been minimal.
Cool roofs markedly reduce how much energy you need to cool a house. When used at scale,they lowerthe air temperatures of entire suburbs.
The simplest way to get a cool roof is to choose one with as light a color as possible. There are also high-tech options able to reflecteven more heat.
Soon, we'll see even higher performance options available in the form of daytime radiative coolers—exceptional cooling materialsable to reflect still more heat away from your house and cut glare.
Until we choose to change, homeowners and whole communities will keep paying dearly for the luxury of a dark roof through power bill pain and sweltering suburbs.
Two teams have observed that electrons, which usually have a charge of –1,can behave as if they had fractional charges(such as –⅔) — and do so without being nudged by an external magnetic field. It’s the first time this ‘fractional quantum anomalous Hall effect’ has been observed experimentally, and physicists are scratching their heads over exactly how it works. It’s a fundamental discovery that might also someday have practical applications: fractionally charged particles are a key requirement for a certain type of quantum computer.
Japanese tits (Parus minor) flutter their wings to invite their mate to enter the nest first. Scientists who observed eight breeding pairs of wild tits noticed that when one of the birds sat in front of the next box and fluttered its wings, the other would go in first. It’s thefirst documented evidence of birds using a symbolic gesture: one that has a specific meaning (like waving ‘goodbye’) but isn’t simply pointing at an object of interest. “It implies that birds have a level of understanding of symbolism that probably a lot of people wouldn’t have given them credit for before.
Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way's central black hole
A new image from the Event Horizon Telescope (EHT) collaboration—which includes scientists from the Center for Astrophysics | Harvard & Smithsonian (CfA)— has uncovered strong and organized magnetic fields spiraling from the edge of the supermassive black hole Sagittarius A* (Sgr A*).
Seen in polarized light for the first time, this new view of the monster lurking at the heart of the Milky Way galaxy has revealed a magnetic field structure strikingly similar to that of the black hole at the center of the M87 galaxy, suggesting that strong magnetic fields may be common to all black holes. This similarity also hints toward a hidden jet in Sgr A*.
The results were published in The Astrophysical Journal Letters.
Scientists unveiled the first image of Sgr A*—which is approximately 27,000 light-years away from Earth—in 2022, revealing that while the Milky Way's supermassive black hole is more than a thousand times smaller and less massive than M87's, it looks remarkably similar.
So scientists decided to check whether they are similar in all the ways possible.
Light is an oscillating or moving, electromagnetic wave that allows us to see objects. Sometimes, light oscillates in a preferred orientation, and we call it "polarized." Although polarized light surrounds us, to human eyes it is indistinguishable from "normal" light.
In the plasma around these black holes, particles whirling around magnetic field lines impart a polarization pattern perpendicular to the field. This allows astronomers to see in increasingly vivid detail what's happening in black hole regions and map their magnetic field lines.
By imaging polarized light from hot glowing gas near black holes, researchers are directly inferring the structure and strength of the magnetic fields that thread the flow of gas and matter that the black hole feeds on and ejects. Polarized light teaches us a lot more about the astrophysics, the properties of the gas, and mechanisms that take place as a black hole feeds.
Scientists are excited to have images of both supermassive black holes in polarized light because these images and the data that come with them provide new ways to compare and contrast black holes of different sizes and masses. As technology improves, the images are likely to reveal even more secrets of black holes and their similarities or differences.
"M87* and Sgr A* are different in a few important ways: M87* is much bigger, and it's pulling in matter from its surroundings at a much faster rate. So, we might have expected that the magnetic fields also look very different. But in this case, they turned out to be quite similar, which may mean that this structure is common to all black holes.
A better understanding of the magnetic fields near black holes helps us answer several open questions—from how jets are formed and launched to what powers the bright flares we see in infrared and X-ray light.
Issaoun, S. et al, First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring,The Astrophysical Journal Letters(2024),DOI: 10.3847/2041-8213/ad2df0
Ricarte A. et al, "First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring,"The Astrophysical Journal Letters(2024),DOI: 10.3847/2041-8213/ad2df1
Making long-term memories requires DNA damage, researchers discover
Just as you can't make an omelet without breaking eggs, scientists at Albert Einstein College of Medicine have found that you can't make long-term memories without DNA damage and brain inflammation. Their surprising findings were published in the journal Nature in a paper titled "Formation of memory assemblies through the DNA sensing TLR9 pathway."
Inflammation of brain neurons is usually considered to be a bad thing, since it can lead to neurological problems such as Alzheimer's and Parkinson's disease. But these new findings suggest that inflammation in certain neurons in the brain's hippocampal region is essential for making long-lasting memories.
The hippocampus has long been known as the brain's memory center. Researchers found that a stimulus sets off a cycle of DNA damage and repair within certain hippocampal neurons that leads to stable memory assemblies—clusters of brain cells that represent our past experiences.
The researchers discovered this memory-forming mechanism by giving mice brief, mild shocks sufficient to form a memory of the shock event (episodic memory). They then analyzed neurons in the hippocampal region and found that genes participating in an important inflammatory signaling pathway had been activated.
Researchers observed strong activation of genes involved in the Toll-Like Receptor 9 (TLR9) pathway. This inflammatory pathway is best known for triggering immune responses by detecting small fragments of pathogen DNA. So at first scientists assumed the TLR9 pathway was activated because the mice had an infection. But looking more closely, they found, to their surprise, that TLR9 was activated only in clusters of hippocampal cells that showed DNA damage.
Brain activity routinely induces small breaks in DNA that are repaired within minutes. But in this population of hippocampal neurons, the DNA damage appeared to be more substantial and sustained.
Further analysis showed that DNA fragments, along with other molecules resulting from the DNA damage, were released from the nucleus, after which the neurons' TLR9 inflammatory pathway was activated; this pathway in turn stimulated DNA repair complexes to form at an unusual location: the centrosomes.
These organelles are present in the cytoplasm of most animal cells and are essential for coordinating cell division. But in neurons—which don't divide—the stimulated centrosomes participated in cycles of DNA repair that appeared to organize individual neurons into memory assemblies.
Cell division and the immune response have been highly conserved in animal life over millions of years, enabling life to continue while providing protection from foreign pathogens.
It seems likely that over the course of evolution, hippocampal neurons have adopted this immune-based memory mechanism by combining the immune response's DNA-sensing TLR9 pathway with a DNA repair centrosome function to form memories without progressing to cell division.
During the week required to complete the inflammatory process, the mouse memory-encoding neurons were found to have changed in various ways, including becoming more resistant to new or similar environmental stimuli.
This is noteworthy because we're constantly flooded by information, and the neurons that encode memories need to preserve the information they've already acquired and not be 'distracted' by new inputs.
Importantly, the researchers found that blocking the TLR9 inflammatory pathway in hippocampal neurons not only prevented mice from forming long-term memories but also caused profound genomic instability, i.e., a high frequency of DNA damage in these neurons.
Genomic instability is considered a hallmark of accelerated aging as well as cancer and psychiatric and neurodegenerative disorders such as Alzheimer's.
Drugs that inhibit the TLR9 pathway have been proposed for relieving the symptoms of long COVID. But caution needs to be shown because fully inhibiting the TLR9 pathway may pose significant health risks, say the researchers.
Scientists discover how caterpillars can stop their 'bleeding' in seconds
Fully grown tobacco hornworms, ready to pupate, are between 7.5cm and 10cm long. They only contain a minute amount of hemolymph, which typically clots within seconds
Blood is a remarkable material: it must remain fluid inside blood vessels, yet clot as quickly as possible outside them, to stop bleeding. The chemical cascade that makes this possible is well understood for vertebrate blood. But hemolymph, the equivalent of blood in insects, has a very different composition, being notably lacking in red blood cells, hemoglobin, and platelets, and having amoeba-like cells called hemocytes instead of white blood cells for immune defense.
Just like blood, hemolymph clots quickly outside the body. How it does so has long remained an enigma. Now, materials scientists have shown in Frontiers in Soft Matter how this feat is managed by caterpillars of the Carolina sphinx moth. This discovery has potential applications for human medicine, the authors said.
These caterpillars, called tobacco hornworms, can seal the wounds within a minute. They do that in two steps: first, in a few seconds, their thin, water-like hemolymph becomes 'viscoelastic' or slimy, and the dripping hemolymph retracts back to the wound.
Next, hemocytes aggregate, starting from the wound surface and moving up to embrace the coating hemolymph film that eventually becomes a crust sealing the wound.
Risk factors for faster aging in the brain revealed in new study
In a new study published in Nature Communications, researchers investigated the genetic and modifiable influences on fragile brain regions by looking at the brain scans of 40,000 UK Biobank participants aged over 45.
Previously, the researchers had identified a 'weak spot' in the brain, which is a specific network of higher-order regions that not only develop later during adolescence, but also show earlier degeneration in old age. They showed that this brain network is also particularly vulnerable to schizophrenia and Alzheimer's disease.
In their latest study, the researchers examined 161 risk factors for dementia, and ranked their impact on this vulnerable brain network, over and above the natural effects of age.
They classified these so-called 'modifiable' risk factors—as they can potentially be changed throughout life to reduce the risk of dementia—into 15 broad categories: blood pressure, cholesterol, diabetes, weight, alcohol consumption, smoking, depressive mood, inflammation, pollution, hearing, sleep, socialization, diet, physical activity, and education.
We know that a constellation of brain regions degenerates earlier in aging, and in this new study researchers have shown that these specific parts of the brain are most vulnerable to diabetes, traffic-related air pollution—increasingly a major player in dementia—and alcohol, of all the common risk factors for dementia.
They have found that several variations in the genome influence this brain network, and they are implicated in cardiovascular deaths, schizophrenia, Alzheimer's and Parkinson's diseases, as well as with the two antigens of a little-known blood group, the elusive XG antigen system, which was an entirely new and unexpected finding.
In fact, two of these seven genetic findings are located in this particular region containing the genes of the XG blood group, and that region is highly atypical because it is shared by both X and Y sex chromosomes. This is really quite intriguing as we do not know much about these parts of the genome; our work shows there is benefit in exploring further this genetic terra incognita.
It is with this kind of comprehensive, holistic approach—and once we had taken into account the effects of age and sex—that three emerged as the most harmful: diabetes, air pollution, and alcohol.
This research sheds light on some of the most critical risk factors for dementia, and provides novel information that can contribute to prevention and future strategies for targeted intervention.
The effects of genetic and modifiable risk factors on brain regions vulnerable to ageing and disease, Nature Communications (2024). DOI: 10.1038/s41467-024-46344-2
'Exhausted' immune cells in healthy women could be target for breast cancer prevention
Risk-reducing surgery, in which the breasts are removed, is offered to those at increased risk of breast cancer. This can be a difficult decision for young womento make and can have a significant effect on body image and conjugal relationships.
Late-stage breast cancer tends to be very unpredictable and hard to manage. As we make better and better drugs, the tumors just seem to find a way around it.
The best way to prevent breast cancer is to really understand how it develops in the first place. Then we can identify these early changes and intervene.
Researchers at the University of Cambridge have created the world's largest catalogue of human breast cells, which has revealed early cell changes in healthy carriers of BRCA1 and BRCA2 gene mutations.
Everyone has BRCA1 and BRCA2 genes, but mutations in these genes—which can be inherited—increase the risk of breast and ovarian cancer.
The study found that the immune cells in breast tissue of healthy women carrying BRCA1 or BRCA2 gene mutations show signs of malfunction known as exhaustion. This suggests that the immune cells can't clear out damaged breast cells, which can eventually develop into breast cancer. This is the first time that exhausted immune cells have been reported in non-cancerous breast tissues at such scale—normally these cells are only found in late-stage tumors. The results raise the possibility of using existing immunotherapy drugs as early intervention to prevent breast cancer developing, in carriers of BRCA1 and BRCA2 gene mutations.
The researchers plan to trial this preventative approach in mice. Existing drugs have serious side effects, so testing in mice is necessary to find the right safe dosage. If effective, this will pave the way to a pilot clinical trial in women carrying BRCA gene mutations.
The research results suggest that in carriers of BRCA mutations, the immune system is failing to kill off damaged breast cells—which in turn seem to be working to keep these immune cells at bay.
Scientists are very excited about this discovery, because it opens up potential for a preventative treatment other than surgery for carriers of BRCA breast cancer gene mutations. Drugs already exist that can overcome this block in immune cell function, but so far, they've only been approved for late-stage disease. No one has really considered using them in a preventative way before.
Using samples of healthy breast tissue collected from 55 women across a range of ages, the researchers catalogued over 800,000 cells—including all the different types of breast cell. The resulting Human Breast Cell Atlas is now available as a resource for other researchers to use and add to. It contains huge amounts of information on other risk factors for breast cancer including Body Mass Index (BMI), menopausal status, contraceptive use and alcohol consumption. Researchers found that there are multiple breast cell types that change with pregnancy, and with age, and it's the combination of these effects—and others—that drives the overall risk of breast cancer.
A single-cell atlas enables mapping of homeostatic cellular shifts in the adult human breast, Nature Genetics (2024). DOI: 10.1038/s41588-024-01688-9
Google Street View reveals how built environment correlates with risk of cardiovascular disease
Researchers have used Google Street View to study hundreds of elements of the built environment, including buildings, green spaces, pavements and roads, and how these elements relate to each other and influence coronary artery disease in people living in these neighborhoods.
Their findings, published in the European Heart Journal recently, show that these factors can predict 63% of the variation in the risk of coronary heart disease from one area to another.
Coronary heart disease, where a build-up of fatty substances in the coronary arteries interrupts the blood supply to the heart, is one of the most common forms of cardiovascular disease.
Researchers say that using Google Street View can help provide an overview of physical environmental risk factors in the built and natural environments that could help not only in understanding risk factors in these environments, but ultimately help towards building or adapting towns and cities to make them healthier places to live.
The research revealed that features of the built environment visible on Google Street View images could predict 63% of the variation in coronary heart disease between these small regions.
The association of residential location with outcomes often supersedes that of known biological risk factors. This is often summarized with the expression that a person's postal code is a bigger determinant of their health than their genetic code. However, our ability to appropriately classify environmental risk factors has relied on population surveys that track wealth, pollution, and community resources.
Zhuo Chen et al, Artificial intelligence-based assessment of built environment from Google Street View and coronary artery disease prevalence,European Heart Journal(2024).DOI: 10.1093/eurheartj/ehae158
Researchers have shown that they can use computer vision approaches to help identify environmental factors influencing cardiovascular risk and this could play a role in guiding heart-healthy urban planning. The fact that they can do this at scale is something that is absolutely unique and important for urban planning.
Climate change is slowing Earth’s rotation Melting ice caps are slowing the rotation of the Earth and could delay the next leap second by three years. Adding or removing seconds every few years keeps official atomic-clock time in line with the natural day, which varies slightly in line with the planet’s rotation rate. Since the early 1990s, the flow of water away from Earth’s axis of rotation and towards the Equator has worked to slightly slow down its spin. “It’s yet another way of impressing upon people just how big a deal [climate change] is,” says geophysicist and study author Duncan Agnew.
Old immune system becomes young again Antibodies rejuvenate immune responses in old mice by targeting stem cells that replenish white and red blood cells. The balance of these stem cells changes as mice (and humans) age — this might be one reason why older animals mount less of an immune response against pathogens. Aged mice that received the antibody treatment had a stronger reaction to vaccination, and were better able to fend off viral infection, than untreated rodents.
Gravitational waves may have made human life possible
Could it be that human existence depends on gravitational waves? Some key elements in our biological makeup may come from astrophysical events that occur because gravitational waves exist, a research team suggests.
In particular, iodine and bromine are found on Earth thanks to a particular nuclear process that happens when neutron stars collide. In turn, orbiting neutron star pairs inspiral and collide due to their emissions of energy in the form of gravitational waves. There may thus be a direct path from the existence of gravitational waves to the existence of mammals.
Humans are mostly made up of hydrogen, carbon and oxygen, with many additional trace elements. (There are 20 elements essential to human life.) Those with an atomic number less than 35 are produced in supernovae, implosions of stars that have exhausted their nuclear fuel and collapsed inward. The collapse results in an explosion that spews their atoms all over the universe.
But two elements are provided by other means—iodine, needed in key hormones produced by the thyroid, and bromine, used to create collagen scaffolds in tissue development and architecture.
Thorium and uranium have been indirectly important for human life, as their radioactive decays in Earth's interior heat the lithosphere and allow tectonic activity. The movement of tectonic plates removes and submerges carbon from the crust of the planet, which is itself removed from the atmosphere via water reacting with carbon dioxide and silicates, avoiding the possibility of a runaway greenhouse effect like has happened on Venus.
About half the heavy elemental atoms on Earth (heavier than iron) are produced by what's known as the "r-process"—the rapid neutron-capture process. The r-process occurs when a heavy atomic nucleus captures a succession of free neutrons before the nucleus has had a chance to decay (usually by beta decay). With a high enough density of free neutrons, calculated to be about 1024 per cubic centimeter, and at high temperatures, around a billion Kelvin, neutrons are absorbed and heavier isotopes of an element are synthesized.
Researchers calculate that the r-process has provided 96% of the abundance of 127I on Earth, an isotope essential for human life, and most of the abundance of bromine and gadolinium in the Earth's crust, plus all of the Earth's thorium and uranium and a fraction of the molybdenum and cadmium.
Where does the r-process occur? One possibility is the material ejected during the rebound from a core-collapse supernova, the explosions of stars near the end of their thermonuclear lifetimes. But there is long-standing uncertainty in the detailed physics of this process. One phenomenon where the r-process does occur is the merger of two neutron stars, called a kilonova. Such mergers are directly caused by gravitational waves.
As the binary pair spiral towards one another over hundreds of millions of years, they radiate an enormous amount of energy in the form of gravitational waves near the end. The amount of energy can be huge—trillions of trillions of watts in the last few milliseconds. Kilonovae outbursts are important sites of the r-process, as neutron stars are made almost entirely of neutrons. Besides the gravitational wave observatories, other detectors detected GW170817 in the electromagnetic spectrum, and found spectroscopic evidence of the material created and tossed out from the merger.
The paper concludes that the iodine essential for human life was "probably produced by the r-process in the collisions of neutron stars that were induced by the emissions of gravitational waves, as well as other essential heavy elements." The group suggests searching for 129I in lunar regolith, which is uncontaminated by manmade sources. Neutron star collisions occur because binary systems lose energy by emitting gravitational waves - so these fundamental physics phenomena may have made human life possible.
An infamous 'inflammasome'—a rogue protein complex—appears to underlie a rare and disabling autoimmune disorder
Autoimmune diseases are among the most puzzling because turncoat constituents of the body wage a constant state of war. Sometimes the underlying cause of an autoimmune condition is so obscure—hidden within chemical miscues of the body—that a long investigatory search must be mounted to sleuth out a cause.
And so it has been with in-depth research to understand an extremely rare autoimmune disorder. The condition is known as CAPS—cryopyrin-associated periodic syndrome. It afflicts patients with an array of disparate symptoms, ranging from skin rashes to permanent hearing loss.
To understand the disorder, scientists have had to explore the influences of cellular biomechanics and the roles of chemical miscues linked to an infamous inflammasome, a protein complex that triggers extreme inflammatory activity. CAPS, scientists now say, occurs because of an inflammasome that's gone rogue. Inflammasomes are multi-protein complexes found in the cytosol of cells that rapidly assemble and activate proinflammatory signaling in response to a diverse number of stimuli.
Normally, inflammasomes guard us against infection and cancer by triggering the domino effect of a powerful immune response. But inflammasome activity can also go awry and cause uncontrolled inflammation. Indeed, conditions known as autoinflammatory disorders, like CAPS, can occur when the body creates an immune response without an easily discernable cue, leading to a host of debilitating lifelong symptoms.
Like CAPS, there are other rare autoinflammatory conditions that cause a range of symptoms, from skin rashes to devastating inflammatory responses leading to fever, blindness, deafness, and cognitive decline.
CAPS, researchers say, is related to the overactivation of a notorious inflammasome—NLRP3—which can be influenced by miscues in mechanical signaling. Mechanical signaling occurs when cells in close contact with each other send errant signals that move through the cytoskeletons of affected cells.
The new research describes how mechanical signaling involving immune cells' membrane proteins can lead to autoimmunity affecting patients with CAPS. The rare disorder, which usually begins in infancy, is marked by waxing and waning lifelong symptoms. It's characterized by rashes, joint pain, red eyes and severe headaches with vomiting. Hearing loss usually occurs during the teen years and is often permanent.
Li Ran et al, KCNN4 links PIEZO-dependent mechanotransduction to NLRP3 inflammasome activation, Science Immunology (2023). DOI: 10.1126/sciimmunol.adf4699
Genetic causes of cerebral palsy uncovered through whole-genome sequencing
A new study by researchers has identified genes which may be partially responsible for the development of cerebral palsy.
Cerebral palsy (CP), a condition that affects the development of motor skills in children, is the most common childhood-onset physical disability. CP can have different causes, such as infections, injuries, or lack of oxygen before or during birth, but the genetic contributors to CP have remained largely unknown till recently.
Novel research by scientists provides a more detailed look into the genetic causes of the condition. Their findings suggest the existence of many genetic variants contributing to CP, which may inform future diagnosis and treatment.
Now that we have a better understanding into the complex relationship between cerebral palsy's genetic and environmental factors, we hope we can improve care for these children.
One in ten children with CP have a genetic variant associated with their condition Published in Nature Genetics, the scientists conducted whole-genome sequencing in 327 children with CP, including their biological parents, and compared it to three independent clinical cohorts as well as two pediatric control cohorts, to identify whether genetic variants may be involved in CP.
The seven-year study found that more than one in ten children (11.3 percent) had a genetic variant or likely genetic variant for their CP, and 17.7 percent of children had variants of uncertain significance that may be linked with CP after further research. Many of the variants also overlapped with other neurodevelopmental conditions, including autism spectrum disorder (ASD), which is highly prevalent in children with CP.
The findings suggest that CP and its causes may be much more diverse than previously thought and showcases the strength of combining precision medicine programs, a movement to deliver individualized care to each patient.
Women with obesity do not need to gain weight during pregnancy, new study suggests
The guidelines for weight gain during pregnancy in obese women have long been questioned. New research supports the idea of lowering or removing the current recommendation of a weight gain of at least 5 kg. The results are published in The Lancet.
International guidelines from the U.S. Institute of Medicine (IOM) state that women with obesity should gain a total of 5 to 9 kg during pregnancy, compared to 11.5 to 16 kg for normal-weight women. The guidelines have long been questioned, but there has been no evidence to warrant a re-examination.
A new study from Karolinska Institutet in Sweden now shows that there are no increased health risks for either the mother or the child with weight gainbelow current guidelines for women with obesity class 1 and 2 (BMI of 30–34.9 and 35–39.9 respectively). On the contrary, for women with obesity class 3 (BMI over 40), weight gain below current guidelines might even be beneficial for those with class 3 obesity.
The study supports previous calls to either lower or remove the current recommended lower limit of a weight gain of at least 5 kg.
The study is based on electronic medical records and registry data for 15,760 women with obesity in Stockholm and Gotland (the so-called Stockholm Gotland Perinatal Cohort). Of the women in the study, 11,667 had obesity class 1; 3,160 had obesity class 2; and 933 had obesity class 3. The study included singleton pregnancies that delivered between 2008 and 2015. The women were followed for a median of eight years after delivery.
Ten known adverse outcomes associated with weight gain during pregnancy were studied: pre-eclampsia, gestational diabetes, excess postpartum weight retention, maternal cardiometabolic disease, unplanned cesarean delivery, preterm birth, large for gestational age and small for gestational age at birth, stillbirth and infant death. These adverse outcomes were assigned weights according to their severity and combined into an adverse composite outcome.
Overall, the study shows no increased risks of the adverse composite outcome with weight gain below current IOM guidelines in women with obesity classes 1 and 2. For women with obesity class 3, on the contrary, weight gain values below the guidelines or weight loss were associated with reduced risk of the adverse composite outcome. For example, an absence of weight gain (i.e., 0kg) was associated with a risk reduction of about 20%.
Based on this, researchers have concluded that weight gain below current recommendations is likely safe in pregnancies with obesity, and might even be beneficial for those with class 3 obesity. The results also indicate that there is a need for specific recommendations for women with class 3 obesity. Unlike today, this group could receive separate recommendations.
Kari Johansson et al, Safety of low weight gain or weight loss in pregnancies with class 1, 2, and 3 obesity: a population-based cohort study, The Lancet (2024). DOI: 10.1016/S0140-6736(24)00255-1
Study shows common water pollutants cause heart damage in fish
Recent findings highlight the persistence of dihalogenated nitrophenols (2,6-DHNPs) in drinking water, resisting standard treatments like sedimentation, filtration, and boiling. The research demonstrates the severe cardiotoxic effects of these contaminants on zebrafish embryos at concentrations as low as 19 μg/L, indicating potential health risks for humans.
2,6-DHNPs, a group of disinfection byproducts (DBPs), are raising alarm bells for public health. These bad actors in the water world are tougher and more toxic than many other pollutants, making it hard for typical water cleaning methods to get rid of them.
They pack a powerful punch, being significantly more harmful to marine life and cells than similar pollutants. Found in places like sewage, swimming pools, and our drinking taps, 2,6-DHNPs are everywhere, signaling a pressing need for better ways to clean our water and keep us safe.
A newstudy, published inEco-Environment & Healthhas uncovered the severe cardiotoxic impacts 2,6-DHNPs have on zebrafish embryos, serving as a model for potential human health risks.
2,6-DHNPs, a group of DBPs resistant to traditional water purification methods like boiling and filtration. These DBPs pose a significant risk, showing a toxicity level 248 times higher than the known regulated DBPs, dichloroacetic acid, in zebrafish embryos. Using zebrafish as a biological model due to their genetic similarity to humans the study meticulously detailed how these emerging contaminants wreak havoc on cardiac health.
The zebrafish embryos exposed to 2,6-DHNPs suffered from severe heart damage characterized by increased production of harmful reactive oxygen species, cell death (apoptosis), and disrupted heart development.
This research underscores a critical environmental and public health issue: the contaminants that survive water treatment processes can lead to severe health outcomes in exposed organisms, hinting at the possible public health risks faced by these persistent waterborne chemicals.
The study revealed that 2,6-DCNP and 2,6-DBNP, two types of DBPs, exhibited significant resistance to removal in drinking water treatment plants. Boiling and filtration were found to be the most effective household water treatment methods, reducing 2,6-DCNP and 2,6-DBNP levels by 47% and 52%, respectively. Exposure to 2,6-DHNPs caused heart failure in zebrafish embryos through increased production of harmful reactive oxygen species (ROS) and delayed heart development. Notably, the antioxidant N-acetyl-L-cysteine was able to mitigate the cardiotoxic effects induced by 2,6-DHNPs.
Hongjie Sun et al, Dihalogenated nitrophenols in drinking water: Prevalence, resistance to household treatment, and cardiotoxic impact on zebrafish embryo, Eco-Environment & Health (2024). DOI: 10.1016/j.eehl.2024.02.004
Keeping cells together—how our body resists mechanical stress
Our body consists of ~30 trillion cells. These cells need to tightly attach to each other to maintain the integrity of our body. However, we are constantly exposed to mechanical stress, which continuously challenges the integrity of our bodies. How are cells able to resist mechanical force to maintain the integrity of our body? Why doesn't our body fall apart when we fall down on the street or when the guts move to digest the food? The secret lies in the cell-to-cell adhesion apparatus that keeps our cells together.
Cells hold on to each other through junctions that serve to connect the neighboring cells. At least three types of junctions are known: tight junctions, adherens junctions, and desmosomes. Previous studies have shown that adherens junctions and desmosomes play critical roles in maintaining the integrity of our body. However, the roles of tight junctions in resisting mechanical stress have not been demonstrated till recently.
One reason that hindered the attempts to understand the roles of tight junctions was that it had been difficult to specifically and completely eliminate its activity due to the overlapping functions of its key constituents. A few years ago, a research group succeeded in generating an epithelial cell line that specifically and completely lacks tight junction membrane proteins claudins and JAM-A, and demonstrated that these cells completely lack tight junctions.
In carefully examining these cells, the researchers found something bizarre. While normal cells are always connected to each other by a continuous belt of cell-to-cell junctions, sporadic disruption and fragmentation of cell-to-cell junctions were observed in these cells. Scientists had never seen something like this before and became curious about this issue.
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The researchers decided to take a movie to find out how the junctions become broken in these cells and found that the junctions fractured when the cells were stretched. The research group further showed that tight junction membrane proteins regulate the conformation change of a protein called ZO-1 in response to mechanical force, suggesting that this mechanosensor is important for cells to resist mechanical stress. This study shows that tight junctions in addition to adherens junctions and desmosomes are important for cells to resist mechanical stress. An interesting question is why we need so many junctions to resist force and how these junctions collaborate to provide mechanical resistance. Scientists would like to tackle these issues in the future.
Thanh Phuong Nguyen et al, Tight junction membrane proteins regulate the mechanical resistance of the apical junctional complex, Journal of Cell Biology (2024). DOI: 10.1083/jcb.202307104
Do sweeteners increase your appetite? New evidence from randomized controlled trial says no
Replacing sugar with artificial and natural sweeteners in foods does not make people hungrier—and also helps to reduce blood sugar levels, a new study has found.
The double-blind randomized controlled trial found that consuming food containing sweeteners produced a similar reduction in appetite sensations and appetite-related hormone responses as sugary foods—and provides some benefits such as lowering blood sugar, which may be particularly important in people at risk of developing type 2 diabetes.
The use of sweeteners in place of sugar in foods can be controversial due to conflicting reports about their potential to increase appetite. Previous studies have been carried out but did not provide robust evidence.
However, the researchers say their study, which meets the gold standard level of proof in scientific investigation, provides very strong evidence that sweeteners and sweetness enhancers do not negatively impact appetite and are beneficial for reducing sugar intake.
The trial consisted of three two-week consumption periods, where participants consumed biscuits with either fruit filling containing sugar, natural sugar substitute Stevia, or artificial sweetener Neotame, each separated by a break of 14-21 days. Day 1 and day 14 of the consumption periods took place in the lab.
The results from the sweetener types showed no differences in appetite or endocrine responses compared to sugar, but insulin levels measured over two hours after eating were reduced, as were blood sugar levels.
: Acute and two-week effects of Neotame, Stevia Rebaudioside M and sucrosesweetened biscuits on postprandial appetite and endocrine response in adults with overweight/obesity – a randomised crossover trial from the SWEET Consortium, eBioMedicine (2024).
Eating more dietary fiber may help prevent type 2 diabetes by promoting beneficial gut bacteria and substances produced during metabolism, according to new research in Hispanic adults.
Consistent evidence suggests diabetes-protective effects of dietary fiber intake, but exactly how does that protection occur?
Consistent evidence suggests diabetes-protective effects of dietary fiber intake, but exactly how that protection occurs remained unclear until recently.
Discovering the connections between dietary fiber, gut bacteria, metabolites and type 2 diabetes—a leading risk factor for heart disease, stroke and kidney disease—could lead to more effective prevention of the condition.
For example, identifying which bacteria and metabolites in the body are linked to type 2 diabetes risk paves the way for personalized diets and treatments to improve gut and metabolic health for people at risk.
The study, published in Circulation Research, looked at data from up to 11,000-plus participants in the ongoing Hispanic Community Health Study/Study of Latinos.
The researchers found that higher fiber intake was associated with specific "good" gut bacteria and certain favorable metabolites in the blood—some of which were actually produced by gut bacteria. Those gut microbes and metabolites were associated with lower risk of developing type 2 diabetes during an average follow-up of six years.
This is new evidence of why a higher intake in dietary fiber is beneficial, specifically to reduce the incidence of new-onset type 2 diabetes.
Dietary fiber is mostly found in fruits, vegetables, nuts, whole grains and cereals. It cannot be broken down, and much of it passes through the system undigested. Its most well-known job is to promote regular bowel movements. But the new research suggests fiber might also be feeding bacteria in the gut.
Bacteria can affect disease risk through a vast array of mechanisms. The complexity was both surprising and fascinating, revealing the deep and nuanced interactions within our gut microbiome.
Although the study's observational design means it could not prove cause and effect, the findings possess strong biological plausibility since some of the specific metabolites highlighted in this study can only be produced by bacteria and not by the human body.
The study also relied on self-reported dietary fiber intake from participants. Dietary fiber is important to metabolic health, and we're beginning to understand why.
Zheng Wang et al, Gut Microbiota and Blood Metabolites Related to Fiber Intake and Type 2 Diabetes, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.123.323634
Nearly one-third of patients with TBI have marginal or inadequate health literacy
Low health literacy is a problem for a substantial proportion of people with moderate to severe traumatic brain injury (TBI), according to research published in The Journal of Head Trauma Rehabilitation (JHTR).
Personal health literacy as an individual's ability to find, understand, and use information about health and health services to make well-informed health decisions for themselves and/or others.
Researchers emphasize that health literacy can impact the comprehension, assimilation, and utilization of health care education and recommendations, and they urge clinicians to attend to health literacy when providing education and recommendations to individuals with TBI.
To help patients with TBI better understand health-related information, the researchers suggest:
Ask patients their preferences for health information format (visual, verbal, or written)
Provide frequent reminders of important health information and related recommendations
Ask patients to express their understanding of the recommendations in their own words
Deliver supplemental instructions via the e-health portal when feasible
Involve care partners in key discussions (eg, those about physical therapy instructions, medication adherence, and healthy lifestyle behaviors)
Flag marginal/inadequate health literacy in theelectronic medical recordso other clinicians can adapt their treatment planning and patient education
Research has demonstrated that individuals with adequate health literacy had better physical and mental health outcomes.
And that is why we bring all this information before you through science communication portals like ours.
Monique R. Pappadis et al, The Relationship of Health Literacy to Health Outcomes Among Individuals With Traumatic Brain Injury: A Traumatic Brain Injury Model Systems Study, Journal of Head Trauma Rehabilitation (2023). DOI: 10.1097/HTR.0000000000000912
Unveiling gender differences in cancer: New insights into genomic instability
Recent research casts a new light on the nuanced interplay between gender and cancer, uncovering significant sex-specific disparities in copy number alterations (CNA) across various cancer types.
Published in Health Data Science, this study delineates the intricate ways in which these alterations influence cancer biology, offering a beacon for future therapeutic strategies.
At the crux of cancer research, understanding the divergent paths this disease takes in men and women is paramount. These latest findings delve into the heart of this divergence, revealing distinct genomic imbalances that underscore the importance of a gender-tailored approach in cancer prognosis and treatment.
The study unveils pronounced differences in genomic instability, particularly in cancers of the kidney, lung, liver, and head and neck, spotlighting the profound impact of sex-biased CNAs on gene expression and their potential as prognostic biomarkers. Remarkably, over 60% of genes within these CNA regions are significantly swayed by these alterations, with approximately 14% of their mRNA abundance being influenced by both gender and CNA.
Insights into these gender-specific genetic alterations pave the way for more personalized cancer care, highlighting the necessity of integrating gender considerations into prognostic models and therapeutic interventions.
Further validating its methodology, the study corroborates the robustness of the CNGPLD tool over traditional statistical approaches, enhancing the accuracy of detecting sex-specific genetic differences. Notably, the research expands its implications beyond the widely acknowledged sex disparities in lung and kidney cancers, identifying critical sex-biased CNA regions in head and neck cancer and lower-grade glioma.
Researchers envision a future where these findings catalyze the development of gender-specific biomarkers and therapeutic avenues, reinforcing the commitment to personalized medicine.
Chenhao Zhang et al, Identification and Analysis of Sex-Biased Copy Number Alterations, Health Data Science (2024). DOI: 10.34133/hds.0121
People with diabetes, atrial fibrillation (a common type of irregular heart rhythm) and treated high blood pressure were at highest risk of going on to develop heart and circulatory diseases. Nearly half of those at highest risk smoked or were living with obesity. Modeling showed that if all current smokers living with obesity were supported to lose weight and quit smoking, the mean 10-year risk in this group would fall from nearly 22% to around 16%.
Kelvin P Jordan et al, Determining cardiovascular risk in patients with unattributed chest pain in UK primary care: an electronic health record study, European Journal of Preventive Cardiology (2023). DOI: 10.1093/eurjpc/zwad055
Researchers discover evolutionary 'tipping point' in fungi
Scientists have found a "tipping point" in the evolution of fungi that throttles their growth and sculpts their shapes. The findings, published in the journal Cell Reports, demonstrate how small changes in environmental factors can lead to huge changes in evolutionary outcomes.
Fungi are nature's great composters. They wait within the forest floor to feed on fallen trees and autumn leaves, releasing essential nutrients from these plants back into the Earth.
Although fungi often bring to mind mushroom caps, fungi also have underground "roots" called mycelia. Mycelia are made up of thousands of interconnected, microscopic, finger-like cells called hyphae that grow into vast networks. Hyphae worm their way through the soil by growing from their tips. To do so, they inflate themselves, similar to the long balloons used to make balloon animals.
Their elongated forms allow hyphae to locate and consume nutrients within the soil. But not all hyphae are the same shape: some have rounded tips, while others are pointed. The hyphae of water molds—fungus-like pathogens that cause blight in crops—are particularly pointy.
A major challenge in biology is to identify the specific evolutionary factors that determine the shape—or form—of a given organism.
To understand the reasons for different shapes of hyphae, researchers combined theory and experiments to investigate fungi and water molds from across nature. They first employed physics-based models of inflationary tip growth to determine all "possible" shapes of hyphae. Surprisingly, the shapes of "actual" hyphae found in nature assumed only a small subset of the possible shapes.
The researchers hypothesized that the limited shapes observed in nature reflected "survival of the fittest," and that the many possible shapes not observed in real fungi were, for some reason, weaker evolutionary rejects. To explore this idea, they examined the growth rate of hyphae with different shapes to create a fitness landscape for hyphae.
Their eureka moment came when they realized that the shapes of hyphae were intimately connected to their ability to grow fast.
A fitness landscape is like a topographic map that visualizes the evolution of an organism: every species wanders through its fitness landscape by testing whether or not random mutations in its genes increase its growth rate, or fitness. A species only stops its restless wandering when a new mutation decreases its fitness—that is, when it is at a fitness peak.
However, researchers found that fitness landscapes can be much more rich than a system of peaks and valleys. In fact, they found that the fitness landscape for hyphae contained an overhanging cliff, or tipping point, and that this acts as a barrier to evolution, strongly limiting the shapes of fungal hyphae. Accordingly, they predicted that hyphae with shapes near the brink of the tipping point would be particularly vulnerable to small environmental, chemical, or genetic changes.
The researchers tested their prediction by treating fungi near the tipping point with small amounts of chemicals that affected hyphal growth. They used one chemical that reduces pressure within the hyphae and another derived from a sea sponge that blocks the hypha's ability to deliver cellular components to the tip of the cell. Both treatments caused the same dramatic effect: the hyphae elongated much more slowly and with a strange nub shape not found in nature.
These findings explain hyphal shape diversity in an enormous, diverse, and important group of species. More broadly, they also demonstrate an important new evolutionary principle: that fitness landscapes can have instabilities, or tipping points, that impose strict constraints on complex traits, like biological form.
The researchers think that their results have critical implications for our understanding of many ecological and evolutionary systems. For example, those species whose evolution is subject to a tipping point may be the most vulnerable to the gradual increase in temperature caused by climate change.
Their findings could also aid in the development of new antimicrobials against disease-causing fungiby identifying vulnerabilities in their growth associated with an evolutionary tipping point.
Planting trees in wrong places heats the planet: Study
Planting trees in the wrong places can actually contribute to global warming, scientists said recently, but a new map identifies the best locations to regrow forests and cool the planet.
Trees soak up carbon dioxide and restoring areas of degraded woodlands or planting saplings to boost forest cover is one tool in the fight against climate change.
But in some cases, more trees means less sunlight is reflected back from the earth's surface and more heat is absorbed by the planet, according to a study in the journal Nature Communications.
There are some places where putting trees back leads to net climate negative outcomes. Scientists had already understood that restoring tree cover led to changes in albedo—the amount of solar radiation bounced back off the planet's surface—but didn't have the tools to account for it.
Using new maps, researchers were able to consider, for the first time, the cooling effect from trees and the warming caused by decreased albedo.
They found that projects that didn't factor albedo into the equation overestimated the climate benefit of additional trees by between 20 to 80 percent.
But the maps also provide the tools to help policymakers identify where best to funnel scarce resources for maximum climate impact.
There's also lots of places still where restoring tree cover is a great idea for climate change Scientists are just trying to help people find those spots.
Albedo is highest in the frozen areas of the world, and mirror-like clean snow and ice with high levels of albedo reflect up to 90 percent of the sun's energy.
It is one of Earth's major cooling agents, along with lands and oceans that absorb excess heat and planet-warming greenhouse gas emissions.
Many countries have promised to plant billions of trees as a bulwark against global warming but not all efforts deliver for the planet equally, this study showed.
Moist, tropical environments like the Amazon and Congo Basin boasted high carbon storage and low changes in albedo, making them ideal locations for restoring forest cover.
The opposite was true in temperate grasslands and savanna.
Even projects in the best locations were probably delivering 20 percent less cooling than estimated when changes to 'albedo' were taken into account.
Restoring forests delivered undeniable benefits for people and the planet, such as supporting ecosystems and providing clean air and water, among many.
(But) we can't put trees everywhere. We don't have enough money or time or resources or people or seedlings.
And so it's really about making the most of limited investments and getting the greatest climate return per hectare of investment, according to researchers.
Natalia Hasler et al, Accounting for albedo change to identify climate-positive tree cover restoration, Nature Communications (2024). DOI: 10.1038/s41467-024-46577-1
Strange Metals Scientists have discovered a new class of materials called “strange metals,” which are characterized by confusing electronic behavior. The class includes a dozen or more materials, such as some copper oxide or iron-based superconductors and twisted bilayer graphene under certain conditions.
How it works: Regular metals are held together by chemical bonds between their atoms. The atoms share negatively charged electrons, and in some cases, the outermost electrons move from one atom to the next, carrying their negative charge with them. But in strange metals, electrons seem to lose their individual identities, acting more like a soup in which all the particles are connected through quantum entanglement.
What the experts say: "Understanding these metals may help us develop superconductors that might operate at or close to room temperature, potentially transforming power grids, quantum computing and medical devices,” writes Douglas Natelson, professor of physics at Rice University.
Cancer Killers Scientists have discovered a gene that might turn white blood cells into cancer cell eating machines. When researchers activated a gene called RAC in human macrophages (white blood cells that naturally engulf harmful substances) in the laboratory, the macrophages turned ravenous for human cancer cells.
Why this matters: A new cancer treatment in early-stage human trials reprograms macrophages to go after cancer calls, but the lead researchers were noticing the macrophages only “nibbling” away at the cancer cells. Activating the RAC gene in the macrophages might supercharge the cells’ “cannibalism” on cancer cells. Researchers hope this kind of therapy, called CAR-M, will be able to target solid tumors, such as breast or lung cancers.
What the experts say: “This is certainly a really exciting translation between an observation of basic biology and applying it to how you could engineer a mammalian immune cell,” says Nathan Singh, an oncologist at Washington University School of Medicine in St. Louis.
Hypervitaminosis A refers to the toxic effects of ingesting too much preformed vitamin A
Diet – Liver is high in vitamin A. The liver of certain animals, including the polar bear, bearded seal, fish and walrus, are particularly toxic (see Liver (food) § Poisoning). It has been estimated that consumption of 500 grams (18 oz) of polar bear liver would result in a toxic dose for a human.
Semi-transparent camera allows for eye tracking without obstructing the view
A team of engineers has developed a nearly transparent camera that can be used for eye tracking without obstructing the view. The team has published a paper describing their camera and its performance as an eye tracker on the arXiv preprint server.
Using technology to track eye movement is beneficial in applications such as virtual reality helmets, automotive assistance devices and even advertising tracking. But the technology has remained stagnant due to one major problem—devices in front of the eyes obstruct the user's view. In this new effort, the researchers in Spain have overcome this problem by developing a camera that is nearly invisible. To create their camera, the research team built a photodetector by adding small dots of lead sulfide to sheets of graphene. When struck by a photon, the dots emit electrons that flow across the layer of carbon atoms, producing a current. And because the materials used to create the photodetector are so small, they are nearly invisible to the naked eye—in tests, it was capable of allowing 95% of light to pass through it.
Further testing involved projecting greyscale patterns onto the photodetector and comparing the output with a standard image sensor. The researchers say the results are promising. They also noted that it had a refresh rate of 400Hz, approximately twice that needed for producing reliable imagery. They then simulated eye tracking by projecting a small dark dot onto the photodetector and used the output to track the action as it occurred.
In practice, the camera could potentially be applied to standard eyeglasses, or better yet, contact lenses. The researchers note, however, that more work is required before their camera could be used for such applications. The photodetector does not have a lens, for example, which means it only works with projected images—and there is the matter of processing imagery and adding a power source for the processor.
Gabriel Mercier et al, Semi-Transparent Image Sensors for Eye-Tracking Applications, arXiv (2024). DOI: 10.48550/arxiv.2403.08297
Windows welcome light into interior spaces, but they also bring in unwanted heat. A new window coating blocks heat-generating ultraviolet and infrared light and lets through visible light, regardless of the sun's angle. The coating can be incorporated onto existing windows or automobiles and can reduce air-conditioning cooling costs by more than one-third in hot climates.
The coating maintains functionality and efficiency whatever the sun's position in the sky.
Seongmin Kim et al, Wide-angle spectral filter for energy-saving windows designed by quantum annealing-enhanced active learning, Cell Reports Physical Science (2024). DOI: 10.1016/j.xcrp.2024.101847
Hair from tiger thought to be extinct found by conservationist on Java
This is good news for Tiger lovers
A team of environmentalists and zoologists affiliated with several institutions in Indonesia has confirmed that a tiger species once thought extinct is still living on the island of Java. In their study, published in the journal Oryx, the group conducted a DNA analysis of a hair found by a conservationist on a plantation on the island. Prior research has shown that the Java tiger once flourished on the island. The tiger is a subspecies of the more well-known Sumatran tiger. But as humans encroached on their territory, leaving little land for the tigers, their numbers began dwindling. After farmers began shooting them for killing livestock, they disappeared completely. In 2008, the species was declared extinct. In this new effort, the research team has found evidence that the declaration may have been premature. Over the past several decades, there have been reports by nonscientists of tigers still living on the island; some even suggested that livestock had been killed by one or more of them. But the sightings were unconfirmed. Then, five years ago, a conservationist working on the island saw what he believed to be a Java tiger on a western part of the island near a plantation. He reported this to a researcher on the island who visited the site and found footprints and claw marks on shrubbery and also a single hair stuck to a fence. A later in-depth interview with the conservationist led the researchers to believe the hair was indeed from a Java tiger. They tested it genetically and compared the results with samples from a museum specimen of a Javan tiger collected in 1930, which showed them to be closely matched. Based on the genetic evidence, the researchers concluded that the hair had come from a Java tiger. The finding shows that the tiger did not go extinct when thought and members of its species had been living on the island, but whether Javan tigers are still there needs to be confirmed with further genetic and field studies.
Wirdateti Wirdateti et al, Is the Javan tiger Panthera tigris sondaica extant? DNA analysis of a recent hair sample, Oryx (2024). DOI: 10.1017/S0030605323001400
Aquagenic Urticaria - commonly known as "water allergy".
Aquagenic urticaria, which has only ever been reportedapproximately 100 times, causes hives to form when a person's skin comes into contact with water, such as in the shower and pool - and sometimes even from a person's own sweat.
The first documented mention of water allergy dates to thelate 20th century, with case reports detailing the perplexing experiences of people afflicted by water-induced hives.
Since then, sporadic cases have dotted medical literature, contributing to our evolving understanding of this ailment. Recent trends suggest a gradual increase in cases, driven by heightened awareness among healthcare professionals and improved diagnostic capabilities.
This rare affliction transforms the seemingly innocuous act of water contact into a tormenting ordeal, afflicting people such as 22-year-old Loren Montefusco from South Carolina, US.
At its core, water allergy is believed to arise from an abnormal immune response triggered by water's interaction with the skin. Think of your immune system as a vigilant guardian, always on alert for invaders. In aquagenic urticaria, water somehow triggers an alarm response. This leads to the release of substances like histamine – causing hives, welts and itching.
Researchers have pinpointed mutations in specific genesassociated with water allergy, such as the FABP5 gene, crucial for skin barrier function. Mutations in this gene disrupt the skin's ability to repel water, activating an inflammatory response.
Variations in genes involved in immune regulation and skin integrity also contribute to susceptibility. However, environmental factors such as hormonal changes or chemical exposure can influence its severity.
Understanding the genetic basis offers insights into how the disease occurs and potential therapies. By identifying specific genetic markers, personalised treatment approaches targeting underlying mechanisms can be developed.
Current estimates suggest that fewer than 100 cases have been reported globally. This underscores its status as one of the rarest form of hives.
Managing this allergy presents a formidable challenge for patients and healthcare providers alike.
Conventional allergy treatments (antihistamines, corticosteroids) offer temporary relief but may not address the underlying cause.
Experimental therapies such as phototherapy (exposing the skin to ultraviolet light) aim to calm the immune response and reduce inflammation. This therapy has shown some promise in alleviating symptoms.
Biologic agents, so-called "large-molecule drugs" made from proteins, target specific immune pathways implicated in allergic reactions. They offer a more targeted therapeutic approach that holds potential for long-term symptom management.
Avoiding water is tricky and involves careful planning, including alternative ways to stay clean. Using protective barriers, such as emollient creams, can help create a layer between the skin and water, which may help reduce symptom severity and frequency. investigation into immune system mechanisms underlying aquagenic urticaria is essential to finding new treatments.
Continued clinical trials and studies are crucial to evaluate the efficacy and safety of emerging therapies, such as phototherapy and biologic agents, in managing aquagenic urticaria. Unfortunately, these studies are limited by patient numbers.
Study reports that age is the driving force in changing how stars move within galaxies
Galaxies start life with their stars rotating in an orderly pattern but in some the motion of stars is more random. Until now, scientists have been uncertain about what causes this—possibly the surrounding environment or the mass of the galaxy itself.
A new study, published in MNRAS (Monthly Notices of the Royal Astronomical Society), has found that the most important factor is neither of these things. It shows the tendency of the stars to have random motion is driven mostly by the age of the galaxy—things just get messy over time.
When researchers did the analysis, they found that age, consistently, whichever way we slice or dice it, is always the most important parameter.
Once you account for age, there is essentially no environmental trend, and it's similar for mass.
"If you find a young galaxy it will be rotating, whatever environmentit is in, and if you find an old galaxy, it will have more random orbits, whether it's in a dense environment or a void.
Young galaxies are star-forming super-factories, while in older ones, star formation ceases.
We do know that age is affected by environment. If a galaxy falls into a dense environment, it will tend to shut down the star formation. So galaxies in denser environments are, on average, older.
The point of their analysis is that it's not living in dense environments that reduces their spin, it's the fact that they're older.
Our own galaxy, the Milky Way, still has a thin star forming disk, so is still considered a high spin rotational galaxy.
"But when we look at the Milky Way in detail, we do see something called the Milky Way thick disk. It's not dominant, in terms of light, but it is there and those look to be older stars, which may well have been heated from the thin disk at earlier times, or born with more turbulent motion in the early universe.
Researchers find a simple way to harvest more 'blue energy' from waves
Waves pack a powerful punch. Now, we are one step closer to capturing the energy behind the ocean's constant ebb and flow with an improved "blue energy" harvesting device.
ResearchersreportinACS Energy Lettersthat simply repositioning the electrode—from the center of a see-sawing liquid-filled tube to the end where the water crashes with the most force—dramatically increased the amount of wave energy that could be harvested.
The tube-shaped wave-energy harvesting device improved upon by the researchers is called a liquid–solid triboelectric nanogenerator (TENG). The TENG converts mechanical energyinto electricity as water sloshes back and forth against the inside of the tube. One reason these devices aren't yet practical for large-scale applications is their low energy output.
aimed to increase a liquid–solid TENG's energy harvesting ability by optimizing the location of the energy-collecting electrode.
The researchers used 16-inch clear plastic tubes to create two TENGs. Inside the first device, they placed a copper foil electrode at the center of the tube—the usual location in conventional liquid–solid TENGs.
For the new design, they inserted a copper foil electrode at one end of the tube. The researchers then filled the tubes a quarter of the way with water and sealed the ends. A wire connected the electrodes to an external circuit.
Placing both devices on a benchtop, the rocker moved water back and forth within the tubes and generated electrical currents by converting mechanical energy—the friction from water hitting or sliding against the electrodes—into electricity. Compared to the conventional design, the researchers found that the optimized design increased the device's conversion of mechanical energy to electrical current by 2.4 times.
In another experiment, the optimized TENG blinked an array of 35 LEDs on and off as water entered the section of the tube covered by the electrodeand then flowed away, respectively.
The researchers say these demonstrations lay the foundation for larger scale blue-energy harvesting from ocean wavesand show their device's potential for other applications like wireless underwater signaling communications.
NASA wants to come up with a new clock for the moon, where seconds tick away faster
NASA wants to come up with an out-of-this-world way to keep track of time, putting the moon on its own clock.
It's not quite a time zone like those on Earth, but an entire frame of time reference for the moon. Because there's less gravity on the moon, time there moves a tad quicker—58.7 microseconds every day—compared to Earth. So the White House Tuesday instructed NASA and other U.S agencies to work with international agencies to come up with a new moon-centric time reference system.
An atomic clock on the moon will tick at a different rate than a clock on Earth. It makes sense that when you go to another body, like the moon or Mars that each one gets its own heartbeat.
So everything on the moon will operate on the speeded-up moon time.
The last time NASA sent astronauts to the moon they wore watches, but timing wasn't as precise and critical as it now with GPS, satellites and intricate computer and communications systems. Those microseconds matter when high tech systems interact.
Last year, the European Space Agency said Earth needs to come up with a unified time for the moon, where a day lasts 29.5 Earth days. The International Space Station, being in low Earth orbit, will continue to use coordinated universal time or UTC. But just where the new space time kicks in is something that NASA has to figure out. Even Earth's time speeds up and slows down, requiring leap seconds.
The White House wants NASA to come up with a preliminary idea by the end of the year and have a final plan by the end of 2026.
NASA is aiming to send astronauts around the moon in September 2025 and land people there a year later.
Source: The Associated Press and other News agencies
Dr. Krishna Kumari Challa
If you've got a dark roof, you're spending almost $700 extra a year to keep your house cool
A dark roof means you'll pay considerably more to keep your house cool in summer.When suburbs are full of dark colored roofs, the whole area heats up. And up. And up. This is part of the urban heat island effect.
Light coloured roofs or Cool roofs have many benefits. They slash how much heat gets into your house from the sun, keep the air surrounding your home cooler, boost your aircon efficiency, and make your solar panels work more efficiently.
At present, the world's cities account for 75% of all energy-related carbon dioxide emissions. It's vitally important we understand what makes cities hotter or cooler.
Brick, concrete, tarmac and tiles can store more heat than grass and tree-covered earth can, and release it slowly over time. This keeps the air warmer, even overnight.
Built-up areas also block wind, which cuts cooling. Then there's transport, manufacturing and air-conditioning, all of which increase heat.
The main way people had to keep cool was through how they designed their homes. In hot countries, buildings are often painted white, as well as having small windows and thick stone walls.
Part 1
Mar 27, 2024
Dr. Krishna Kumari Challa
How can we cool our cities
If your street has established large trees, you will experience less than half the number of days with extreme heat compared on residents on treeless streets. If you live in a leafy street, your home is also worth more.
Blacktop roads are a surprisingly large source of heat. In summer, they can get up to 75°C. Research shows reflective sealants can cut the temperatures up to 13°C. Some councils have experimented with lighter roads, but to date, uptake has been minimal.
Cool roofs markedly reduce how much energy you need to cool a house. When used at scale, they lower the air temperatures of entire suburbs.
The simplest way to get a cool roof is to choose one with as light a color as possible. There are also high-tech options able to reflect even more heat.
Soon, we'll see even higher performance options available in the form of daytime radiative coolers—exceptional cooling materials able to reflect still more heat away from your house and cut glare.
Until we choose to change, homeowners and whole communities will keep paying dearly for the luxury of a dark roof through power bill pain and sweltering suburbs.
https://theconversation.com/if-youve-got-a-dark-roof-youre-spending...
Part 2
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Mar 27, 2024
Dr. Krishna Kumari Challa
Weird electron behaviour thrills physicists
Two teams have observed that electrons, which usually have a charge of –1, can behave as if they had fractional charges (such as –⅔) — and do so without being nudged by an external magnetic field. It’s the first time this ‘fractional quantum anomalous Hall effect’ has been observed experimentally, and physicists are scratching their heads over exactly how it works. It’s a fundamental discovery that might also someday have practical applications: fractionally charged particles are a key requirement for a certain type of quantum computer.
Mar 27, 2024
Dr. Krishna Kumari Challa
symbolic gesture in birds
Japanese tits (Parus minor) flutter their wings to invite their mate to enter the nest first. Scientists who observed eight breeding pairs of wild tits noticed that when one of the birds sat in front of the next box and fluttered its wings, the other would go in first. It’s the first documented evidence of birds using a symbolic gesture: one that has a specific meaning (like waving ‘goodbye’) but isn’t simply pointing at an object of interest. “It implies that birds have a level of understanding of symbolism that probably a lot of people wouldn’t have given them credit for before.
Mar 27, 2024
Dr. Krishna Kumari Challa
Astronomers unveil strong magnetic fields spiraling at the edge of Milky Way's central black hole
A new image from the Event Horizon Telescope (EHT) collaboration—which includes scientists from the Center for Astrophysics | Harvard & Smithsonian (CfA)— has uncovered strong and organized magnetic fields spiraling from the edge of the supermassive black hole Sagittarius A* (Sgr A*).
Seen in polarized light for the first time, this new view of the monster lurking at the heart of the Milky Way galaxy has revealed a magnetic field structure strikingly similar to that of the black hole at the center of the M87 galaxy, suggesting that strong magnetic fields may be common to all black holes. This similarity also hints toward a hidden jet in Sgr A*.
The results were published in The Astrophysical Journal Letters.
Scientists unveiled the first image of Sgr A*—which is approximately 27,000 light-years away from Earth—in 2022, revealing that while the Milky Way's supermassive black hole is more than a thousand times smaller and less massive than M87's, it looks remarkably similar.
So scientists decided to check whether they are similar in all the ways possible.
Part 1
Mar 28, 2024
Dr. Krishna Kumari Challa
Light is an oscillating or moving, electromagnetic wave that allows us to see objects. Sometimes, light oscillates in a preferred orientation, and we call it "polarized." Although polarized light surrounds us, to human eyes it is indistinguishable from "normal" light.
In the plasma around these black holes, particles whirling around magnetic field lines impart a polarization pattern perpendicular to the field. This allows astronomers to see in increasingly vivid detail what's happening in black hole regions and map their magnetic field lines.
By imaging polarized light from hot glowing gas near black holes, researchers are directly inferring the structure and strength of the magnetic fields that thread the flow of gas and matter that the black hole feeds on and ejects. Polarized light teaches us a lot more about the astrophysics, the properties of the gas, and mechanisms that take place as a black hole feeds.
Scientists are excited to have images of both supermassive black holes in polarized light because these images and the data that come with them provide new ways to compare and contrast black holes of different sizes and masses. As technology improves, the images are likely to reveal even more secrets of black holes and their similarities or differences.
"M87* and Sgr A* are different in a few important ways: M87* is much bigger, and it's pulling in matter from its surroundings at a much faster rate. So, we might have expected that the magnetic fields also look very different. But in this case, they turned out to be quite similar, which may mean that this structure is common to all black holes.
A better understanding of the magnetic fields near black holes helps us answer several open questions—from how jets are formed and launched to what powers the bright flares we see in infrared and X-ray light.
Issaoun, S. et al, First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring, The Astrophysical Journal Letters (2024), DOI: 10.3847/2041-8213/ad2df0
Ricarte A. et al, "First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring," The Astrophysical Journal Letters (2024), DOI: 10.3847/2041-8213/ad2df1
Part 2
Mar 28, 2024
Dr. Krishna Kumari Challa
Making long-term memories requires DNA damage, researchers discover
Just as you can't make an omelet without breaking eggs, scientists at Albert Einstein College of Medicine have found that you can't make long-term memories without DNA damage and brain inflammation. Their surprising findings were published in the journal Nature in a paper titled "Formation of memory assemblies through the DNA sensing TLR9 pathway."
Inflammation of brain neurons is usually considered to be a bad thing, since it can lead to neurological problems such as Alzheimer's and Parkinson's disease. But these new findings suggest that inflammation in certain neurons in the brain's hippocampal region is essential for making long-lasting memories.
The hippocampus has long been known as the brain's memory center. Researchers found that a stimulus sets off a cycle of DNA damage and repair within certain hippocampal neurons that leads to stable memory assemblies—clusters of brain cells that represent our past experiences.
The researchers discovered this memory-forming mechanism by giving mice brief, mild shocks sufficient to form a memory of the shock event (episodic memory). They then analyzed neurons in the hippocampal region and found that genes participating in an important inflammatory signaling pathway had been activated.
Researchers observed strong activation of genes involved in the Toll-Like Receptor 9 (TLR9) pathway. This inflammatory pathway is best known for triggering immune responses by detecting small fragments of pathogen DNA. So at first scientists assumed the TLR9 pathway was activated because the mice had an infection. But looking more closely, they found, to their surprise, that TLR9 was activated only in clusters of hippocampal cells that showed DNA damage.
Brain activity routinely induces small breaks in DNA that are repaired within minutes. But in this population of hippocampal neurons, the DNA damage appeared to be more substantial and sustained.
Part 1
Mar 28, 2024
Dr. Krishna Kumari Challa
Triggering inflammation to make memories
Further analysis showed that DNA fragments, along with other molecules resulting from the DNA damage, were released from the nucleus, after which the neurons' TLR9 inflammatory pathway was activated; this pathway in turn stimulated DNA repair complexes to form at an unusual location: the centrosomes.
These organelles are present in the cytoplasm of most animal cells and are essential for coordinating cell division. But in neurons—which don't divide—the stimulated centrosomes participated in cycles of DNA repair that appeared to organize individual neurons into memory assemblies.
Cell division and the immune response have been highly conserved in animal life over millions of years, enabling life to continue while providing protection from foreign pathogens.
It seems likely that over the course of evolution, hippocampal neurons have adopted this immune-based memory mechanism by combining the immune response's DNA-sensing TLR9 pathway with a DNA repair centrosome function to form memories without progressing to cell division.
Part 2
Mar 28, 2024
Dr. Krishna Kumari Challa
During the week required to complete the inflammatory process, the mouse memory-encoding neurons were found to have changed in various ways, including becoming more resistant to new or similar environmental stimuli.
This is noteworthy because we're constantly flooded by information, and the neurons that encode memories need to preserve the information they've already acquired and not be 'distracted' by new inputs.
Importantly, the researchers found that blocking the TLR9 inflammatory pathway in hippocampal neurons not only prevented mice from forming long-term memories but also caused profound genomic instability, i.e., a high frequency of DNA damage in these neurons.
Genomic instability is considered a hallmark of accelerated aging as well as cancer and psychiatric and neurodegenerative disorders such as Alzheimer's.
Drugs that inhibit the TLR9 pathway have been proposed for relieving the symptoms of long COVID. But caution needs to be shown because fully inhibiting the TLR9 pathway may pose significant health risks, say the researchers.
Jelena Radulovic, Formation of memory assemblies through the DNA-sensing TLR9 pathway, Nature (2024). DOI: 10.1038/s41586-024-07220-7. www.nature.com/articles/s41586-024-07220-7
Part 3
Mar 28, 2024
Dr. Krishna Kumari Challa
Scientists discover how caterpillars can stop their 'bleeding' in seconds
Fully grown tobacco hornworms, ready to pupate, are between 7.5cm and 10cm long. They only contain a minute amount of hemolymph, which typically clots within seconds
Blood is a remarkable material: it must remain fluid inside blood vessels, yet clot as quickly as possible outside them, to stop bleeding. The chemical cascade that makes this possible is well understood for vertebrate blood. But hemolymph, the equivalent of blood in insects, has a very different composition, being notably lacking in red blood cells, hemoglobin, and platelets, and having amoeba-like cells called hemocytes instead of white blood cells for immune defense.
Just like blood, hemolymph clots quickly outside the body. How it does so has long remained an enigma. Now, materials scientists have shown in Frontiers in Soft Matter how this feat is managed by caterpillars of the Carolina sphinx moth. This discovery has potential applications for human medicine, the authors said.
These caterpillars, called tobacco hornworms, can seal the wounds within a minute. They do that in two steps: first, in a few seconds, their thin, water-like hemolymph becomes 'viscoelastic' or slimy, and the dripping hemolymph retracts back to the wound.
Next, hemocytes aggregate, starting from the wound surface and moving up to embrace the coating hemolymph film that eventually becomes a crust sealing the wound.
To seal a wound, caterpillars transform blood from a viscous to a viscoelastic fluid in a few seconds, Frontiers in Soft Matter (2024). DOI: 10.3389/frsfm.2024.1341129. www.frontiersin.org/articles/1 … fm.2024.1341129/full
Mar 28, 2024
Dr. Krishna Kumari Challa
Risk factors for faster aging in the brain revealed in new study
In a new study published in Nature Communications, researchers investigated the genetic and modifiable influences on fragile brain regions by looking at the brain scans of 40,000 UK Biobank participants aged over 45.
Previously, the researchers had identified a 'weak spot' in the brain, which is a specific network of higher-order regions that not only develop later during adolescence, but also show earlier degeneration in old age. They showed that this brain network is also particularly vulnerable to schizophrenia and Alzheimer's disease.
In their latest study, the researchers examined 161 risk factors for dementia, and ranked their impact on this vulnerable brain network, over and above the natural effects of age.
They classified these so-called 'modifiable' risk factors—as they can potentially be changed throughout life to reduce the risk of dementia—into 15 broad categories: blood pressure, cholesterol, diabetes, weight, alcohol consumption, smoking, depressive mood, inflammation, pollution, hearing, sleep, socialization, diet, physical activity, and education.
We know that a constellation of brain regions degenerates earlier in aging, and in this new study researchers have shown that these specific parts of the brain are most vulnerable to diabetes, traffic-related air pollution—increasingly a major player in dementia—and alcohol, of all the common risk factors for dementia.
They have found that several variations in the genome influence this brain network, and they are implicated in cardiovascular deaths, schizophrenia, Alzheimer's and Parkinson's diseases, as well as with the two antigens of a little-known blood group, the elusive XG antigen system, which was an entirely new and unexpected finding.
Part 1
Mar 28, 2024
Dr. Krishna Kumari Challa
In fact, two of these seven genetic findings are located in this particular region containing the genes of the XG blood group, and that region is highly atypical because it is shared by both X and Y sex chromosomes. This is really quite intriguing as we do not know much about these parts of the genome; our work shows there is benefit in exploring further this genetic terra incognita.
It is with this kind of comprehensive, holistic approach—and once we had taken into account the effects of age and sex—that three emerged as the most harmful: diabetes, air pollution, and alcohol.
This research sheds light on some of the most critical risk factors for dementia, and provides novel information that can contribute to prevention and future strategies for targeted intervention.
The effects of genetic and modifiable risk factors on brain regions vulnerable to ageing and disease, Nature Communications (2024). DOI: 10.1038/s41467-024-46344-2
Part 2
Mar 28, 2024
Dr. Krishna Kumari Challa
'Exhausted' immune cells in healthy women could be target for breast cancer prevention
Risk-reducing surgery, in which the breasts are removed, is offered to those at increased risk of breast cancer. This can be a difficult decision for young women to make and can have a significant effect on body image and conjugal relationships.
Late-stage breast cancer tends to be very unpredictable and hard to manage. As we make better and better drugs, the tumors just seem to find a way around it.
The best way to prevent breast cancer is to really understand how it develops in the first place. Then we can identify these early changes and intervene.
Researchers at the University of Cambridge have created the world's largest catalogue of human breast cells, which has revealed early cell changes in healthy carriers of BRCA1 and BRCA2 gene mutations.
Everyone has BRCA1 and BRCA2 genes, but mutations in these genes—which can be inherited—increase the risk of breast and ovarian cancer.
The study found that the immune cells in breast tissue of healthy women carrying BRCA1 or BRCA2 gene mutations show signs of malfunction known as exhaustion. This suggests that the immune cells can't clear out damaged breast cells, which can eventually develop into breast cancer.
This is the first time that exhausted immune cells have been reported in non-cancerous breast tissues at such scale—normally these cells are only found in late-stage tumors. The results raise the possibility of using existing immunotherapy drugs as early intervention to prevent breast cancer developing, in carriers of BRCA1 and BRCA2 gene mutations.
The researchers plan to trial this preventative approach in mice. Existing drugs have serious side effects, so testing in mice is necessary to find the right safe dosage. If effective, this will pave the way to a pilot clinical trial in women carrying BRCA gene mutations.
The research results suggest that in carriers of BRCA mutations, the immune system is failing to kill off damaged breast cells—which in turn seem to be working to keep these immune cells at bay.
Scientists are very excited about this discovery, because it opens up potential for a preventative treatment other than surgery for carriers of BRCA breast cancer gene mutations. Drugs already exist that can overcome this block in immune cell function, but so far, they've only been approved for late-stage disease. No one has really considered using them in a preventative way before.
Using samples of healthy breast tissue collected from 55 women across a range of ages, the researchers catalogued over 800,000 cells—including all the different types of breast cell. The resulting Human Breast Cell Atlas is now available as a resource for other researchers to use and add to. It contains huge amounts of information on other risk factors for breast cancer including Body Mass Index (BMI), menopausal status, contraceptive use and alcohol consumption. Researchers found that there are multiple breast cell types that change with pregnancy, and with age, and it's the combination of these effects—and others—that drives the overall risk of breast cancer.
A single-cell atlas enables mapping of homeostatic cellular shifts in the adult human breast, Nature Genetics (2024). DOI: 10.1038/s41588-024-01688-9
Mar 29, 2024
Dr. Krishna Kumari Challa
Google Street View reveals how built environment correlates with risk of cardiovascular disease
Researchers have used Google Street View to study hundreds of elements of the built environment, including buildings, green spaces, pavements and roads, and how these elements relate to each other and influence coronary artery disease in people living in these neighborhoods.
Their findings, published in the European Heart Journal recently, show that these factors can predict 63% of the variation in the risk of coronary heart disease from one area to another.
Coronary heart disease, where a build-up of fatty substances in the coronary arteries interrupts the blood supply to the heart, is one of the most common forms of cardiovascular disease.
Researchers say that using Google Street View can help provide an overview of physical environmental risk factors in the built and natural environments that could help not only in understanding risk factors in these environments, but ultimately help towards building or adapting towns and cities to make them healthier places to live.
The research revealed that features of the built environment visible on Google Street View images could predict 63% of the variation in coronary heart disease between these small regions.
The association of residential location with outcomes often supersedes that of known biological risk factors. This is often summarized with the expression that a person's postal code is a bigger determinant of their health than their genetic code. However, our ability to appropriately classify environmental risk factors has relied on population surveys that track wealth, pollution, and community resources.
Zhuo Chen et al, Artificial intelligence-based assessment of built environment from Google Street View and coronary artery disease prevalence, European Heart Journal (2024). DOI: 10.1093/eurheartj/ehae158
Rohan Khera, Artificial intelligence-enhanced exposomics: novel insights into cardiovascular health, European Heart Journal (2024). DOI: 10.1093/eurheartj/ehae159
Researchers have shown that they can use computer vision approaches to help identify environmental factors influencing cardiovascular risk and this could play a role in guiding heart-healthy urban planning. The fact that they can do this at scale is something that is absolutely unique and important for urban planning.
Mar 29, 2024
Dr. Krishna Kumari Challa
Climate change is slowing Earth’s rotation
Melting ice caps are slowing the rotation of the Earth and could delay the next leap second by three years. Adding or removing seconds every few years keeps official atomic-clock time in line with the natural day, which varies slightly in line with the planet’s rotation rate. Since the early 1990s, the flow of water away from Earth’s axis of rotation and towards the Equator has worked to slightly slow down its spin. “It’s yet another way of impressing upon people just how big a deal [climate change] is,” says geophysicist and study author Duncan Agnew.
https://www.nature.com/articles/d41586-024-00932-w?utm_source=Live+...
Mar 29, 2024
Dr. Krishna Kumari Challa
Old immune system becomes young again
Antibodies rejuvenate immune responses in old mice by targeting stem cells that replenish white and red blood cells. The balance of these stem cells changes as mice (and humans) age — this might be one reason why older animals mount less of an immune response against pathogens. Aged mice that received the antibody treatment had a stronger reaction to vaccination, and were better able to fend off viral infection, than untreated rodents.
Nature |
Read an expert analysis by developmental biologist Yasar Arfat Kasu and stem-cell biologist Robert Signer in the Nature News & Views article
Reference: Nature paper
Mar 29, 2024
Dr. Krishna Kumari Challa
Gravitational waves may have made human life possible
Could it be that human existence depends on gravitational waves? Some key elements in our biological makeup may come from astrophysical events that occur because gravitational waves exist, a research team suggests.
In particular, iodine and bromine are found on Earth thanks to a particular nuclear process that happens when neutron stars collide. In turn, orbiting neutron star pairs inspiral and collide due to their emissions of energy in the form of gravitational waves. There may thus be a direct path from the existence of gravitational waves to the existence of mammals.
Humans are mostly made up of hydrogen, carbon and oxygen, with many additional trace elements. (There are 20 elements essential to human life.) Those with an atomic number less than 35 are produced in supernovae, implosions of stars that have exhausted their nuclear fuel and collapsed inward. The collapse results in an explosion that spews their atoms all over the universe.
But two elements are provided by other means—iodine, needed in key hormones produced by the thyroid, and bromine, used to create collagen scaffolds in tissue development and architecture.
Thorium and uranium have been indirectly important for human life, as their radioactive decays in Earth's interior heat the lithosphere and allow tectonic activity. The movement of tectonic plates removes and submerges carbon from the crust of the planet, which is itself removed from the atmosphere via water reacting with carbon dioxide and silicates, avoiding the possibility of a runaway greenhouse effect like has happened on Venus.
About half the heavy elemental atoms on Earth (heavier than iron) are produced by what's known as the "r-process"—the rapid neutron-capture process. The r-process occurs when a heavy atomic nucleus captures a succession of free neutrons before the nucleus has had a chance to decay (usually by beta decay). With a high enough density of free neutrons, calculated to be about 1024 per cubic centimeter, and at high temperatures, around a billion Kelvin, neutrons are absorbed and heavier isotopes of an element are synthesized.
Part 1
Mar 30, 2024
Dr. Krishna Kumari Challa
Researchers calculate that the r-process has provided 96% of the abundance of 127I on Earth, an isotope essential for human life, and most of the abundance of bromine and gadolinium in the Earth's crust, plus all of the Earth's thorium and uranium and a fraction of the molybdenum and cadmium.
Where does the r-process occur? One possibility is the material ejected during the rebound from a core-collapse supernova, the explosions of stars near the end of their thermonuclear lifetimes. But there is long-standing uncertainty in the detailed physics of this process.
One phenomenon where the r-process does occur is the merger of two neutron stars, called a kilonova. Such mergers are directly caused by gravitational waves.
As the binary pair spiral towards one another over hundreds of millions of years, they radiate an enormous amount of energy in the form of gravitational waves near the end. The amount of energy can be huge—trillions of trillions of watts in the last few milliseconds.
Kilonovae outbursts are important sites of the r-process, as neutron stars are made almost entirely of neutrons. Besides the gravitational wave observatories, other detectors detected GW170817 in the electromagnetic spectrum, and found spectroscopic evidence of the material created and tossed out from the merger.
The paper concludes that the iodine essential for human life was "probably produced by the r-process in the collisions of neutron stars that were induced by the emissions of gravitational waves, as well as other essential heavy elements." The group suggests searching for 129I in lunar regolith, which is uncontaminated by manmade sources.
Neutron star collisions occur because binary systems lose energy by emitting gravitational waves - so these fundamental physics phenomena may have made human life possible.
John Ellis et al, Do we owe our existence to gravitational waves?, arXiv (2024). DOI: 10.48550/arxiv.2402.03593
Part 2
Mar 30, 2024
Dr. Krishna Kumari Challa
An infamous 'inflammasome'—a rogue protein complex—appears to underlie a rare and disabling autoimmune disorder
Autoimmune diseases are among the most puzzling because turncoat constituents of the body wage a constant state of war. Sometimes the underlying cause of an autoimmune condition is so obscure—hidden within chemical miscues of the body—that a long investigatory search must be mounted to sleuth out a cause.
And so it has been with in-depth research to understand an extremely rare autoimmune disorder. The condition is known as CAPS—cryopyrin-associated periodic syndrome. It afflicts patients with an array of disparate symptoms, ranging from skin rashes to permanent hearing loss.
To understand the disorder, scientists have had to explore the influences of cellular biomechanics and the roles of chemical miscues linked to an infamous inflammasome, a protein complex that triggers extreme inflammatory activity. CAPS, scientists now say, occurs because of an inflammasome that's gone rogue. Inflammasomes are multi-protein complexes found in the cytosol of cells that rapidly assemble and activate proinflammatory signaling in response to a diverse number of stimuli.
Normally, inflammasomes guard us against infection and cancer by triggering the domino effect of a powerful immune response. But inflammasome activity can also go awry and cause uncontrolled inflammation. Indeed, conditions known as autoinflammatory disorders, like CAPS, can occur when the body creates an immune response without an easily discernable cue, leading to a host of debilitating lifelong symptoms.
Like CAPS, there are other rare autoinflammatory conditions that cause a range of symptoms, from skin rashes to devastating inflammatory responses leading to fever, blindness, deafness, and cognitive decline.
CAPS, researchers say, is related to the overactivation of a notorious inflammasome—NLRP3—which can be influenced by miscues in mechanical signaling. Mechanical signaling occurs when cells in close contact with each other send errant signals that move through the cytoskeletons of affected cells.
The new research describes how mechanical signaling involving immune cells' membrane proteins can lead to autoimmunity affecting patients with CAPS. The rare disorder, which usually begins in infancy, is marked by waxing and waning lifelong symptoms. It's characterized by rashes, joint pain, red eyes and severe headaches with vomiting. Hearing loss usually occurs during the teen years and is often permanent.
Li Ran et al, KCNN4 links PIEZO-dependent mechanotransduction to NLRP3 inflammasome activation, Science Immunology (2023). DOI: 10.1126/sciimmunol.adf4699
Mar 30, 2024
Dr. Krishna Kumari Challa
Genetic causes of cerebral palsy uncovered through whole-genome sequencing
A new study by researchers has identified genes which may be partially responsible for the development of cerebral palsy.
Cerebral palsy (CP), a condition that affects the development of motor skills in children, is the most common childhood-onset physical disability. CP can have different causes, such as infections, injuries, or lack of oxygen before or during birth, but the genetic contributors to CP have remained largely unknown till recently.
Novel research by scientists provides a more detailed look into the genetic causes of the condition. Their findings suggest the existence of many genetic variants contributing to CP, which may inform future diagnosis and treatment.
Now that we have a better understanding into the complex relationship between cerebral palsy's genetic and environmental factors, we hope we can improve care for these children.
One in ten children with CP have a genetic variant associated with their condition Published in Nature Genetics, the scientists conducted whole-genome sequencing in 327 children with CP, including their biological parents, and compared it to three independent clinical cohorts as well as two pediatric control cohorts, to identify whether genetic variants may be involved in CP.
The seven-year study found that more than one in ten children (11.3 percent) had a genetic variant or likely genetic variant for their CP, and 17.7 percent of children had variants of uncertain significance that may be linked with CP after further research. Many of the variants also overlapped with other neurodevelopmental conditions, including autism spectrum disorder (ASD), which is highly prevalent in children with CP.
The findings suggest that CP and its causes may be much more diverse than previously thought and showcases the strength of combining precision medicine programs, a movement to deliver individualized care to each patient.
Comprehensive whole-genome sequence analyses provide insights into the genomic architecture of cerebral palsy, Nature Genetics (2024). DOI: 10.1038/s41588-024-01686-x. www.nature.com/articles/s41588-024-01686-x
Mar 30, 2024
Dr. Krishna Kumari Challa
Women with obesity do not need to gain weight during pregnancy, new study suggests
The guidelines for weight gain during pregnancy in obese women have long been questioned. New research supports the idea of lowering or removing the current recommendation of a weight gain of at least 5 kg. The results are published in The Lancet.
International guidelines from the U.S. Institute of Medicine (IOM) state that women with obesity should gain a total of 5 to 9 kg during pregnancy, compared to 11.5 to 16 kg for normal-weight women. The guidelines have long been questioned, but there has been no evidence to warrant a re-examination.
A new study from Karolinska Institutet in Sweden now shows that there are no increased health risks for either the mother or the child with weight gain below current guidelines for women with obesity class 1 and 2 (BMI of 30–34.9 and 35–39.9 respectively). On the contrary, for women with obesity class 3 (BMI over 40), weight gain below current guidelines might even be beneficial for those with class 3 obesity.
The study supports previous calls to either lower or remove the current recommended lower limit of a weight gain of at least 5 kg.
Part 1
Mar 30, 2024
Dr. Krishna Kumari Challa
The study is based on electronic medical records and registry data for 15,760 women with obesity in Stockholm and Gotland (the so-called Stockholm Gotland Perinatal Cohort). Of the women in the study, 11,667 had obesity class 1; 3,160 had obesity class 2; and 933 had obesity class 3. The study included singleton pregnancies that delivered between 2008 and 2015. The women were followed for a median of eight years after delivery.
Ten known adverse outcomes associated with weight gain during pregnancy were studied: pre-eclampsia, gestational diabetes, excess postpartum weight retention, maternal cardiometabolic disease, unplanned cesarean delivery, preterm birth, large for gestational age and small for gestational age at birth, stillbirth and infant death. These adverse outcomes were assigned weights according to their severity and combined into an adverse composite outcome.
Overall, the study shows no increased risks of the adverse composite outcome with weight gain below current IOM guidelines in women with obesity classes 1 and 2. For women with obesity class 3, on the contrary, weight gain values below the guidelines or weight loss were associated with reduced risk of the adverse composite outcome. For example, an absence of weight gain (i.e., 0kg) was associated with a risk reduction of about 20%.
Based on this, researchers have concluded that weight gain below current recommendations is likely safe in pregnancies with obesity, and might even be beneficial for those with class 3 obesity.
The results also indicate that there is a need for specific recommendations for women with class 3 obesity. Unlike today, this group could receive separate recommendations.
Kari Johansson et al, Safety of low weight gain or weight loss in pregnancies with class 1, 2, and 3 obesity: a population-based cohort study, The Lancet (2024). DOI: 10.1016/S0140-6736(24)00255-1
Part 2
Mar 30, 2024
Dr. Krishna Kumari Challa
What causes a landslide? | Natural Disasters
Mar 30, 2024
Dr. Krishna Kumari Challa
Study shows common water pollutants cause heart damage in fish
Recent findings highlight the persistence of dihalogenated nitrophenols (2,6-DHNPs) in drinking water, resisting standard treatments like sedimentation, filtration, and boiling. The research demonstrates the severe cardiotoxic effects of these contaminants on zebrafish embryos at concentrations as low as 19 μg/L, indicating potential health risks for humans.
2,6-DHNPs, a group of disinfection byproducts (DBPs), are raising alarm bells for public health. These bad actors in the water world are tougher and more toxic than many other pollutants, making it hard for typical water cleaning methods to get rid of them.
They pack a powerful punch, being significantly more harmful to marine life and cells than similar pollutants. Found in places like sewage, swimming pools, and our drinking taps, 2,6-DHNPs are everywhere, signaling a pressing need for better ways to clean our water and keep us safe.
A new study, published in Eco-Environment & Health has uncovered the severe cardiotoxic impacts 2,6-DHNPs have on zebrafish embryos, serving as a model for potential human health risks.
2,6-DHNPs, a group of DBPs resistant to traditional water purification methods like boiling and filtration. These DBPs pose a significant risk, showing a toxicity level 248 times higher than the known regulated DBPs, dichloroacetic acid, in zebrafish embryos. Using zebrafish as a biological model due to their genetic similarity to humans the study meticulously detailed how these emerging contaminants wreak havoc on cardiac health.
The zebrafish embryos exposed to 2,6-DHNPs suffered from severe heart damage characterized by increased production of harmful reactive oxygen species, cell death (apoptosis), and disrupted heart development.
This research underscores a critical environmental and public health issue: the contaminants that survive water treatment processes can lead to severe health outcomes in exposed organisms, hinting at the possible public health risks faced by these persistent waterborne chemicals.
The study revealed that 2,6-DCNP and 2,6-DBNP, two types of DBPs, exhibited significant resistance to removal in drinking water treatment plants. Boiling and filtration were found to be the most effective household water treatment methods, reducing 2,6-DCNP and 2,6-DBNP levels by 47% and 52%, respectively. Exposure to 2,6-DHNPs caused heart failure in zebrafish embryos through increased production of harmful reactive oxygen species (ROS) and delayed heart development. Notably, the antioxidant N-acetyl-L-cysteine was able to mitigate the cardiotoxic effects induced by 2,6-DHNPs.
Hongjie Sun et al, Dihalogenated nitrophenols in drinking water: Prevalence, resistance to household treatment, and cardiotoxic impact on zebrafish embryo, Eco-Environment & Health (2024). DOI: 10.1016/j.eehl.2024.02.004
Mar 30, 2024
Dr. Krishna Kumari Challa
Keeping cells together—how our body resists mechanical stress
Our body consists of ~30 trillion cells. These cells need to tightly attach to each other to maintain the integrity of our body. However, we are constantly exposed to mechanical stress, which continuously challenges the integrity of our bodies. How are cells able to resist mechanical force to maintain the integrity of our body? Why doesn't our body fall apart when we fall down on the street or when the guts move to digest the food? The secret lies in the cell-to-cell adhesion apparatus that keeps our cells together.
Cells hold on to each other through junctions that serve to connect the neighboring cells. At least three types of junctions are known: tight junctions, adherens junctions, and desmosomes. Previous studies have shown that adherens junctions and desmosomes play critical roles in maintaining the integrity of our body. However, the roles of tight junctions in resisting mechanical stress have not been demonstrated till recently.One reason that hindered the attempts to understand the roles of tight junctions was that it had been difficult to specifically and completely eliminate its activity due to the overlapping functions of its key constituents. A few years ago, a research group succeeded in generating an epithelial cell line that specifically and completely lacks tight junction membrane proteins claudins and JAM-A, and demonstrated that these cells completely lack tight junctions.
In carefully examining these cells, the researchers found something bizarre. While normal cells are always connected to each other by a continuous belt of cell-to-cell junctions, sporadic disruption and fragmentation of cell-to-cell junctions were observed in these cells. Scientists had never seen something like this before and became curious about this issue.
Part 1
Mar 30, 2024
Dr. Krishna Kumari Challa
The researchers decided to take a movie to find out how the junctions become broken in these cells and found that the junctions fractured when the cells were stretched. The research group further showed that tight junction membrane proteins regulate the conformation change of a protein called ZO-1 in response to mechanical force, suggesting that this mechanosensor is important for cells to resist mechanical stress.
This study shows that tight junctions in addition to adherens junctions and desmosomes are important for cells to resist mechanical stress. An interesting question is why we need so many junctions to resist force and how these junctions collaborate to provide mechanical resistance. Scientists would like to tackle these issues in the future.
Thanh Phuong Nguyen et al, Tight junction membrane proteins regulate the mechanical resistance of the apical junctional complex, Journal of Cell Biology (2024). DOI: 10.1083/jcb.202307104
Part 2
Mar 30, 2024
Dr. Krishna Kumari Challa
Do sweeteners increase your appetite? New evidence from randomized controlled trial says no
Replacing sugar with artificial and natural sweeteners in foods does not make people hungrier—and also helps to reduce blood sugar levels, a new study has found.
The double-blind randomized controlled trial found that consuming food containing sweeteners produced a similar reduction in appetite sensations and appetite-related hormone responses as sugary foods—and provides some benefits such as lowering blood sugar, which may be particularly important in people at risk of developing type 2 diabetes.
The use of sweeteners in place of sugar in foods can be controversial due to conflicting reports about their potential to increase appetite. Previous studies have been carried out but did not provide robust evidence.
However, the researchers say their study, which meets the gold standard level of proof in scientific investigation, provides very strong evidence that sweeteners and sweetness enhancers do not negatively impact appetite and are beneficial for reducing sugar intake.
The trial consisted of three two-week consumption periods, where participants consumed biscuits with either fruit filling containing sugar, natural sugar substitute Stevia, or artificial sweetener Neotame, each separated by a break of 14-21 days. Day 1 and day 14 of the consumption periods took place in the lab.
The results from the sweetener types showed no differences in appetite or endocrine responses compared to sugar, but insulin levels measured over two hours after eating were reduced, as were blood sugar levels.
: Acute and two-week effects of Neotame, Stevia Rebaudioside M and sucrosesweetened biscuits on postprandial appetite and endocrine response in adults with overweight/obesity – a randomised crossover trial from the SWEET Consortium, eBioMedicine (2024).
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Mar 30, 2024
Dr. Krishna Kumari Challa
How might fiber lower diabetes risk?
Eating more dietary fiber may help prevent type 2 diabetes by promoting beneficial gut bacteria and substances produced during metabolism, according to new research in Hispanic adults.
Consistent evidence suggests diabetes-protective effects of dietary fiber intake, but exactly how does that protection occur?
Consistent evidence suggests diabetes-protective effects of dietary fiber intake, but exactly how that protection occurs remained unclear until recently.
Discovering the connections between dietary fiber, gut bacteria, metabolites and type 2 diabetes—a leading risk factor for heart disease, stroke and kidney disease—could lead to more effective prevention of the condition.
For example, identifying which bacteria and metabolites in the body are linked to type 2 diabetes risk paves the way for personalized diets and treatments to improve gut and metabolic health for people at risk.
The study, published in Circulation Research, looked at data from up to 11,000-plus participants in the ongoing Hispanic Community Health Study/Study of Latinos.
The researchers found that higher fiber intake was associated with specific "good" gut bacteria and certain favorable metabolites in the blood—some of which were actually produced by gut bacteria. Those gut microbes and metabolites were associated with lower risk of developing type 2 diabetes during an average follow-up of six years.
This is new evidence of why a higher intake in dietary fiber is beneficial, specifically to reduce the incidence of new-onset type 2 diabetes.
Dietary fiber is mostly found in fruits, vegetables, nuts, whole grains and cereals. It cannot be broken down, and much of it passes through the system undigested. Its most well-known job is to promote regular bowel movements. But the new research suggests fiber might also be feeding bacteria in the gut.
Bacteria can affect disease risk through a vast array of mechanisms. The complexity was both surprising and fascinating, revealing the deep and nuanced interactions within our gut microbiome.
Part 1
Mar 30, 2024
Dr. Krishna Kumari Challa
Although the study's observational design means it could not prove cause and effect, the findings possess strong biological plausibility since some of the specific metabolites highlighted in this study can only be produced by bacteria and not by the human body.
The study also relied on self-reported dietary fiber intake from participants. Dietary fiber is important to metabolic health, and we're beginning to understand why.
Zheng Wang et al, Gut Microbiota and Blood Metabolites Related to Fiber Intake and Type 2 Diabetes, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.123.323634
Part 2
Mar 30, 2024
Dr. Krishna Kumari Challa
Nearly one-third of patients with TBI have marginal or inadequate health literacy
Low health literacy is a problem for a substantial proportion of people with moderate to severe traumatic brain injury (TBI), according to research published in The Journal of Head Trauma Rehabilitation (JHTR).
Personal health literacy as an individual's ability to find, understand, and use information about health and health services to make well-informed health decisions for themselves and/or others.
Researchers emphasize that health literacy can impact the comprehension, assimilation, and utilization of health care education and recommendations, and they urge clinicians to attend to health literacy when providing education and recommendations to individuals with TBI.
To help patients with TBI better understand health-related information, the researchers suggest:
Part 1
Mar 30, 2024
Dr. Krishna Kumari Challa
Research has demonstrated that individuals with adequate health literacy had better physical and mental health outcomes.
And that is why we bring all this information before you through science communication portals like ours.
Monique R. Pappadis et al, The Relationship of Health Literacy to Health Outcomes Among Individuals With Traumatic Brain Injury: A Traumatic Brain Injury Model Systems Study, Journal of Head Trauma Rehabilitation (2023). DOI: 10.1097/HTR.0000000000000912
Part 2
Mar 30, 2024
Dr. Krishna Kumari Challa
Unveiling gender differences in cancer: New insights into genomic instability
Recent research casts a new light on the nuanced interplay between gender and cancer, uncovering significant sex-specific disparities in copy number alterations (CNA) across various cancer types.
Published in Health Data Science, this study delineates the intricate ways in which these alterations influence cancer biology, offering a beacon for future therapeutic strategies.
At the crux of cancer research, understanding the divergent paths this disease takes in men and women is paramount. These latest findings delve into the heart of this divergence, revealing distinct genomic imbalances that underscore the importance of a gender-tailored approach in cancer prognosis and treatment.
The study unveils pronounced differences in genomic instability, particularly in cancers of the kidney, lung, liver, and head and neck, spotlighting the profound impact of sex-biased CNAs on gene expression and their potential as prognostic biomarkers. Remarkably, over 60% of genes within these CNA regions are significantly swayed by these alterations, with approximately 14% of their mRNA abundance being influenced by both gender and CNA.
Insights into these gender-specific genetic alterations pave the way for more personalized cancer care, highlighting the necessity of integrating gender considerations into prognostic models and therapeutic interventions.
Further validating its methodology, the study corroborates the robustness of the CNGPLD tool over traditional statistical approaches, enhancing the accuracy of detecting sex-specific genetic differences. Notably, the research expands its implications beyond the widely acknowledged sex disparities in lung and kidney cancers, identifying critical sex-biased CNA regions in head and neck cancer and lower-grade glioma.
Researchers envision a future where these findings catalyze the development of gender-specific biomarkers and therapeutic avenues, reinforcing the commitment to personalized medicine.
Chenhao Zhang et al, Identification and Analysis of Sex-Biased Copy Number Alterations, Health Data Science (2024). DOI: 10.34133/hds.0121
Mar 30, 2024
Dr. Krishna Kumari Challa
People with diabetes, atrial fibrillation (a common type of irregular heart rhythm) and treated high blood pressure were at highest risk of going on to develop heart and circulatory diseases.
Nearly half of those at highest risk smoked or were living with obesity. Modeling showed that if all current smokers living with obesity were supported to lose weight and quit smoking, the mean 10-year risk in this group would fall from nearly 22% to around 16%.
Kelvin P Jordan et al, Determining cardiovascular risk in patients with unattributed chest pain in UK primary care: an electronic health record study, European Journal of Preventive Cardiology (2023). DOI: 10.1093/eurjpc/zwad055
Mar 30, 2024
Dr. Krishna Kumari Challa
Researchers discover evolutionary 'tipping point' in fungi
Scientists have found a "tipping point" in the evolution of fungi that throttles their growth and sculpts their shapes. The findings, published in the journal Cell Reports, demonstrate how small changes in environmental factors can lead to huge changes in evolutionary outcomes.
Fungi are nature's great composters. They wait within the forest floor to feed on fallen trees and autumn leaves, releasing essential nutrients from these plants back into the Earth.
Although fungi often bring to mind mushroom caps, fungi also have underground "roots" called mycelia. Mycelia are made up of thousands of interconnected, microscopic, finger-like cells called hyphae that grow into vast networks. Hyphae worm their way through the soil by growing from their tips. To do so, they inflate themselves, similar to the long balloons used to make balloon animals.
Their elongated forms allow hyphae to locate and consume nutrients within the soil. But not all hyphae are the same shape: some have rounded tips, while others are pointed. The hyphae of water molds—fungus-like pathogens that cause blight in crops—are particularly pointy.
A major challenge in biology is to identify the specific evolutionary factors that determine the shape—or form—of a given organism.
Part 1
Apr 1, 2024
Dr. Krishna Kumari Challa
To understand the reasons for different shapes of hyphae, researchers combined theory and experiments to investigate fungi and water molds from across nature. They first employed physics-based models of inflationary tip growth to determine all "possible" shapes of hyphae. Surprisingly, the shapes of "actual" hyphae found in nature assumed only a small subset of the possible shapes.
The researchers hypothesized that the limited shapes observed in nature reflected "survival of the fittest," and that the many possible shapes not observed in real fungi were, for some reason, weaker evolutionary rejects. To explore this idea, they examined the growth rate of hyphae with different shapes to create a fitness landscape for hyphae.
Their eureka moment came when they realized that the shapes of hyphae were intimately connected to their ability to grow fast.
A fitness landscape is like a topographic map that visualizes the evolution of an organism: every species wanders through its fitness landscape by testing whether or not random mutations in its genes increase its growth rate, or fitness. A species only stops its restless wandering when a new mutation decreases its fitness—that is, when it is at a fitness peak.
However, researchers found that fitness landscapes can be much more rich than a system of peaks and valleys. In fact, they found that the fitness landscape for hyphae contained an overhanging cliff, or tipping point, and that this acts as a barrier to evolution, strongly limiting the shapes of fungal hyphae. Accordingly, they predicted that hyphae with shapes near the brink of the tipping point would be particularly vulnerable to small environmental, chemical, or genetic changes.
The researchers tested their prediction by treating fungi near the tipping point with small amounts of chemicals that affected hyphal growth. They used one chemical that reduces pressure within the hyphae and another derived from a sea sponge that blocks the hypha's ability to deliver cellular components to the tip of the cell. Both treatments caused the same dramatic effect: the hyphae elongated much more slowly and with a strange nub shape not found in nature.
These findings explain hyphal shape diversity in an enormous, diverse, and important group of species. More broadly, they also demonstrate an important new evolutionary principle: that fitness landscapes can have instabilities, or tipping points, that impose strict constraints on complex traits, like biological form.
The researchers think that their results have critical implications for our understanding of many ecological and evolutionary systems. For example, those species whose evolution is subject to a tipping point may be the most vulnerable to the gradual increase in temperature caused by climate change.
Their findings could also aid in the development of new antimicrobials against disease-causing fungi by identifying vulnerabilities in their growth associated with an evolutionary tipping point.
A fitness landscape instability governs the morphological diversity of tip-growing cells, Cell Reports (2024). DOI: 10.1016/j.celrep.2024.113961. www.cell.com/cell-reports/full … 2211-1247(24)00289-4
Part 2
Apr 1, 2024
Dr. Krishna Kumari Challa
Planting trees in wrong places heats the planet: Study
Planting trees in the wrong places can actually contribute to global warming, scientists said recently, but a new map identifies the best locations to regrow forests and cool the planet.
Trees soak up carbon dioxide and restoring areas of degraded woodlands or planting saplings to boost forest cover is one tool in the fight against climate change.
But in some cases, more trees means less sunlight is reflected back from the earth's surface and more heat is absorbed by the planet, according to a study in the journal Nature Communications.
There are some places where putting trees back leads to net climate negative outcomes. Scientists had already understood that restoring tree cover led to changes in albedo—the amount of solar radiation bounced back off the planet's surface—but didn't have the tools to account for it.
Using new maps, researchers were able to consider, for the first time, the cooling effect from trees and the warming caused by decreased albedo.
They found that projects that didn't factor albedo into the equation overestimated the climate benefit of additional trees by between 20 to 80 percent.
But the maps also provide the tools to help policymakers identify where best to funnel scarce resources for maximum climate impact.
There's also lots of places still where restoring tree cover is a great idea for climate change Scientists are just trying to help people find those spots.
Part 1
Apr 2, 2024
Dr. Krishna Kumari Challa
Albedo is highest in the frozen areas of the world, and mirror-like clean snow and ice with high levels of albedo reflect up to 90 percent of the sun's energy.
It is one of Earth's major cooling agents, along with lands and oceans that absorb excess heat and planet-warming greenhouse gas emissions.
Many countries have promised to plant billions of trees as a bulwark against global warming but not all efforts deliver for the planet equally, this study showed.
Moist, tropical environments like the Amazon and Congo Basin boasted high carbon storage and low changes in albedo, making them ideal locations for restoring forest cover.
The opposite was true in temperate grasslands and savanna.
Even projects in the best locations were probably delivering 20 percent less cooling than estimated when changes to 'albedo' were taken into account.
Restoring forests delivered undeniable benefits for people and the planet, such as supporting ecosystems and providing clean air and water, among many.
(But) we can't put trees everywhere. We don't have enough money or time or resources or people or seedlings.
And so it's really about making the most of limited investments and getting the greatest climate return per hectare of investment, according to researchers.
Natalia Hasler et al, Accounting for albedo change to identify climate-positive tree cover restoration, Nature Communications (2024). DOI: 10.1038/s41467-024-46577-1
Part 2
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Apr 2, 2024
Dr. Krishna Kumari Challa
Strange Metals
Scientists have discovered a new class of materials called “strange metals,” which are characterized by confusing electronic behavior. The class includes a dozen or more materials, such as some copper oxide or iron-based superconductors and twisted bilayer graphene under certain conditions.
How it works: Regular metals are held together by chemical bonds between their atoms. The atoms share negatively charged electrons, and in some cases, the outermost electrons move from one atom to the next, carrying their negative charge with them. But in strange metals, electrons seem to lose their individual identities, acting more like a soup in which all the particles are connected through quantum entanglement.
What the experts say: "Understanding these metals may help us develop superconductors that might operate at or close to room temperature, potentially transforming power grids, quantum computing and medical devices,” writes Douglas Natelson, professor of physics at Rice University.
confusing electronic behavior.
Apr 2, 2024
Dr. Krishna Kumari Challa
Cancer Killers
Scientists have discovered a gene that might turn white blood cells into cancer cell eating machines. When researchers activated a gene called RAC in human macrophages (white blood cells that naturally engulf harmful substances) in the laboratory, the macrophages turned ravenous for human cancer cells.
Why this matters: A new cancer treatment in early-stage human trials reprograms macrophages to go after cancer calls, but the lead researchers were noticing the macrophages only “nibbling” away at the cancer cells. Activating the RAC gene in the macrophages might supercharge the cells’ “cannibalism” on cancer cells. Researchers hope this kind of therapy, called CAR-M, will be able to target solid tumors, such as breast or lung cancers.
macrophages turned ravenous for human cancer cells.
What the experts say: “This is certainly a really exciting translation between an observation of basic biology and applying it to how you could engineer a mammalian immune cell,” says Nathan Singh, an oncologist at Washington University School of Medicine in St. Louis.
Apr 2, 2024
Dr. Krishna Kumari Challa
Hypervitaminosis A refers to the toxic effects of ingesting too much preformed vitamin A
Diet – Liver is high in vitamin A. The liver of certain animals, including the polar bear, bearded seal, fish and walrus, are particularly toxic (see Liver (food) § Poisoning). It has been estimated that consumption of 500 grams (18 oz) of polar bear liver would result in a toxic dose for a human.
Apr 2, 2024
Dr. Krishna Kumari Challa
Semi-transparent camera allows for eye tracking without obstructing the view
A team of engineers has developed a nearly transparent camera that can be used for eye tracking without obstructing the view. The team has published a paper describing their camera and its performance as an eye tracker on the arXiv preprint server.
Using technology to track eye movement is beneficial in applications such as virtual reality helmets, automotive assistance devices and even advertising tracking. But the technology has remained stagnant due to one major problem—devices in front of the eyes obstruct the user's view. In this new effort, the researchers in Spain have overcome this problem by developing a camera that is nearly invisible.
To create their camera, the research team built a photodetector by adding small dots of lead sulfide to sheets of graphene. When struck by a photon, the dots emit electrons that flow across the layer of carbon atoms, producing a current. And because the materials used to create the photodetector are so small, they are nearly invisible to the naked eye—in tests, it was capable of allowing 95% of light to pass through it.
Further testing involved projecting greyscale patterns onto the photodetector and comparing the output with a standard image sensor. The researchers say the results are promising. They also noted that it had a refresh rate of 400Hz, approximately twice that needed for producing reliable imagery. They then simulated eye tracking by projecting a small dark dot onto the photodetector and used the output to track the action as it occurred.
In practice, the camera could potentially be applied to standard eyeglasses, or better yet, contact lenses. The researchers note, however, that more work is required before their camera could be used for such applications. The photodetector does not have a lens, for example, which means it only works with projected images—and there is the matter of processing imagery and adding a power source for the processor.
Gabriel Mercier et al, Semi-Transparent Image Sensors for Eye-Tracking Applications, arXiv (2024). DOI: 10.48550/arxiv.2403.08297
Apr 3, 2024
Dr. Krishna Kumari Challa
A new window coating blocks heat, not view
Windows welcome light into interior spaces, but they also bring in unwanted heat. A new window coating blocks heat-generating ultraviolet and infrared light and lets through visible light, regardless of the sun's angle. The coating can be incorporated onto existing windows or automobiles and can reduce air-conditioning cooling costs by more than one-third in hot climates.
The coating maintains functionality and efficiency whatever the sun's position in the sky.
Seongmin Kim et al, Wide-angle spectral filter for energy-saving windows designed by quantum annealing-enhanced active learning, Cell Reports Physical Science (2024). DOI: 10.1016/j.xcrp.2024.101847
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Apr 3, 2024
Dr. Krishna Kumari Challa
How The Internet Travels Across Oceans
Apr 3, 2024
Dr. Krishna Kumari Challa
Hair from tiger thought to be extinct found by conservationist on Java
This is good news for Tiger lovers
A team of environmentalists and zoologists affiliated with several institutions in Indonesia has confirmed that a tiger species once thought extinct is still living on the island of Java. In their study, published in the journal Oryx, the group conducted a DNA analysis of a hair found by a conservationist on a plantation on the island. Prior research has shown that the Java tiger once flourished on the island. The tiger is a subspecies of the more well-known Sumatran tiger. But as humans encroached on their territory, leaving little land for the tigers, their numbers began dwindling. After farmers began shooting them for killing livestock, they disappeared completely. In 2008, the species was declared extinct. In this new effort, the research team has found evidence that the declaration may have been premature. Over the past several decades, there have been reports by nonscientists of tigers still living on the island; some even suggested that livestock had been killed by one or more of them. But the sightings were unconfirmed. Then, five years ago, a conservationist working on the island saw what he believed to be a Java tiger on a western part of the island near a plantation. He reported this to a researcher on the island who visited the site and found footprints and claw marks on shrubbery and also a single hair stuck to a fence. A later in-depth interview with the conservationist led the researchers to believe the hair was indeed from a Java tiger. They tested it genetically and compared the results with samples from a museum specimen of a Javan tiger collected in 1930, which showed them to be closely matched. Based on the genetic evidence, the researchers concluded that the hair had come from a Java tiger. The finding shows that the tiger did not go extinct when thought and members of its species had been living on the island, but whether Javan tigers are still there needs to be confirmed with further genetic and field studies.
Wirdateti Wirdateti et al, Is the Javan tiger Panthera tigris sondaica extant? DNA analysis of a recent hair sample, Oryx (2024). DOI: 10.1017/S0030605323001400
Apr 3, 2024
Dr. Krishna Kumari Challa
Aquagenic Urticaria - commonly known as "water allergy".
Aquagenic urticaria, which has only ever been reported approximately 100 times, causes hives to form when a person's skin comes into contact with water, such as in the shower and pool - and sometimes even from a person's own sweat.
The first documented mention of water allergy dates to the late 20th century, with case reports detailing the perplexing experiences of people afflicted by water-induced hives.
Since then, sporadic cases have dotted medical literature, contributing to our evolving understanding of this ailment. Recent trends suggest a gradual increase in cases, driven by heightened awareness among healthcare professionals and improved diagnostic capabilities.
This rare affliction transforms the seemingly innocuous act of water contact into a tormenting ordeal, afflicting people such as 22-year-old Loren Montefusco from South Carolina, US.
At its core, water allergy is believed to arise from an abnormal immune response triggered by water's interaction with the skin. Think of your immune system as a vigilant guardian, always on alert for invaders. In aquagenic urticaria, water somehow triggers an alarm response. This leads to the release of substances like histamine – causing hives, welts and itching.
Researchers have pinpointed mutations in specific genes associated with water allergy, such as the FABP5 gene, crucial for skin barrier function. Mutations in this gene disrupt the skin's ability to repel water, activating an inflammatory response.
Apr 3, 2024
Dr. Krishna Kumari Challa
Current estimates suggest that fewer than 100 cases have been reported globally. This underscores its status as one of the rarest form of hives.
Managing this allergy presents a formidable challenge for patients and healthcare providers alike.
Conventional allergy treatments (antihistamines, corticosteroids) offer temporary relief but may not address the underlying cause.
Experimental therapies such as phototherapy (exposing the skin to ultraviolet light) aim to calm the immune response and reduce inflammation. This therapy has shown some promise in alleviating symptoms.
Biologic agents, so-called "large-molecule drugs" made from proteins, target specific immune pathways implicated in allergic reactions. They offer a more targeted therapeutic approach that holds potential for long-term symptom management.
Avoiding water is tricky and involves careful planning, including alternative ways to stay clean.
Using protective barriers, such as emollient creams, can help create a layer between the skin and water, which may help reduce symptom severity and frequency.
investigation into immune system mechanisms underlying aquagenic urticaria is essential to finding new treatments.
Continued clinical trials and studies are crucial to evaluate the efficacy and safety of emerging therapies, such as phototherapy and biologic agents, in managing aquagenic urticaria. Unfortunately, these studies are limited by patient numbers.
https://theconversation.com/water-allergy-a-debilitating-but-thankf...
Part 2
Apr 3, 2024
Dr. Krishna Kumari Challa
Study reports that age is the driving force in changing how stars move within galaxies
Galaxies start life with their stars rotating in an orderly pattern but in some the motion of stars is more random. Until now, scientists have been uncertain about what causes this—possibly the surrounding environment or the mass of the galaxy itself.
A new study, published in MNRAS (Monthly Notices of the Royal Astronomical Society), has found that the most important factor is neither of these things. It shows the tendency of the stars to have random motion is driven mostly by the age of the galaxy—things just get messy over time.
When researchers did the analysis, they found that age, consistently, whichever way we slice or dice it, is always the most important parameter.
Once you account for age, there is essentially no environmental trend, and it's similar for mass.
"If you find a young galaxy it will be rotating, whatever environment it is in, and if you find an old galaxy, it will have more random orbits, whether it's in a dense environment or a void.
Young galaxies are star-forming super-factories, while in older ones, star formation ceases.
We do know that age is affected by environment. If a galaxy falls into a dense environment, it will tend to shut down the star formation. So galaxies in denser environments are, on average, older.
The point of their analysis is that it's not living in dense environments that reduces their spin, it's the fact that they're older.
Part 1
Apr 4, 2024
Dr. Krishna Kumari Challa
Our own galaxy, the Milky Way, still has a thin star forming disk, so is still considered a high spin rotational galaxy.
"But when we look at the Milky Way in detail, we do see something called the Milky Way thick disk. It's not dominant, in terms of light, but it is there and those look to be older stars, which may well have been heated from the thin disk at earlier times, or born with more turbulent motion in the early universe.
Scott Croom et al, The SAMI Galaxy Survey: galaxy spin is more strongly correlated with stellar population age than mass or environment, Monthly Notices of the Royal Astronomical Society (2024). DOI: 10.1093/mnras/stae458. academic.oup.com/mnras/article … 0.1093/mnras/stae458
Part 2
Apr 4, 2024
Dr. Krishna Kumari Challa
Researchers find a simple way to harvest more 'blue energy' from waves
Waves pack a powerful punch. Now, we are one step closer to capturing the energy behind the ocean's constant ebb and flow with an improved "blue energy" harvesting device.
Researchers report in ACS Energy Letters that simply repositioning the electrode—from the center of a see-sawing liquid-filled tube to the end where the water crashes with the most force—dramatically increased the amount of wave energy that could be harvested.
The tube-shaped wave-energy harvesting device improved upon by the researchers is called a liquid–solid triboelectric nanogenerator (TENG). The TENG converts mechanical energy into electricity as water sloshes back and forth against the inside of the tube. One reason these devices aren't yet practical for large-scale applications is their low energy output.
aimed to increase a liquid–solid TENG's energy harvesting ability by optimizing the location of the energy-collecting electrode.
The researchers used 16-inch clear plastic tubes to create two TENGs. Inside the first device, they placed a copper foil electrode at the center of the tube—the usual location in conventional liquid–solid TENGs.
For the new design, they inserted a copper foil electrode at one end of the tube. The researchers then filled the tubes a quarter of the way with water and sealed the ends. A wire connected the electrodes to an external circuit.
Placing both devices on a benchtop, the rocker moved water back and forth within the tubes and generated electrical currents by converting mechanical energy—the friction from water hitting or sliding against the electrodes—into electricity. Compared to the conventional design, the researchers found that the optimized design increased the device's conversion of mechanical energy to electrical current by 2.4 times.
In another experiment, the optimized TENG blinked an array of 35 LEDs on and off as water entered the section of the tube covered by the electrode and then flowed away, respectively.
The researchers say these demonstrations lay the foundation for larger scale blue-energy harvesting from ocean waves and show their device's potential for other applications like wireless underwater signaling communications.
Space Volume Effect in Tube Liquid–Solid Triboelectric Nanogenerator for Output Performance Enhancement, ACS Energy Letters (2024). DOI: 10.1021/acsenergylett.4c00072. pubs.acs.org/doi/abs/10.1021/acsenergylett.4c00072
Apr 4, 2024
Dr. Krishna Kumari Challa
NASA wants to come up with a new clock for the moon, where seconds tick away faster
NASA wants to come up with an out-of-this-world way to keep track of time, putting the moon on its own clock.
It's not quite a time zone like those on Earth, but an entire frame of time reference for the moon. Because there's less gravity on the moon, time there moves a tad quicker—58.7 microseconds every day—compared to Earth. So the White House Tuesday instructed NASA and other U.S agencies to work with international agencies to come up with a new moon-centric time reference system.
An atomic clock on the moon will tick at a different rate than a clock on Earth. It makes sense that when you go to another body, like the moon or Mars that each one gets its own heartbeat.
So everything on the moon will operate on the speeded-up moon time.
The last time NASA sent astronauts to the moon they wore watches, but timing wasn't as precise and critical as it now with GPS, satellites and intricate computer and communications systems. Those microseconds matter when high tech systems interact.
Last year, the European Space Agency said Earth needs to come up with a unified time for the moon, where a day lasts 29.5 Earth days. The International Space Station, being in low Earth orbit, will continue to use coordinated universal time or UTC. But just where the new space time kicks in is something that NASA has to figure out. Even Earth's time speeds up and slows down, requiring leap seconds.
The White House wants NASA to come up with a preliminary idea by the end of the year and have a final plan by the end of 2026.
NASA is aiming to send astronauts around the moon in September 2025 and land people there a year later.
Source: The Associated Press and other News agencies
Apr 4, 2024