Scientists discover a natural flu defense mechanism that activates in the nasal cavity during pregnancy

Scientists have discovered that pregnancy may trigger a natural immunity to boost protection against severe flu infection. Their work is published in the journal Science Advances.

Contrary to the common belief that pregnancy increases vulnerability to infections, researchers found that it strengthened an immune defense in mice, blocking the Influenza A virus from spreading to the lungs, where it can cause severe infection.

A mother needs to stay healthy to protect her developing baby, so the immune system adapts to provide stronger defenses. This fascinating response in the nasal cavity  is the body's way of adding an extra layer of protection, which turns on during pregnancy.

The researchers used a mouse model to observe how a certain type of immune cell activates in the nasal cavity of mice during pregnancy, producing a powerful molecule that boosts the body's antiviral defenses, especially in the nose and upper airways.

This natural immunity in pregnancy could change the way we think about flu protection for expectant mothers

Julia Chronopoulos et al, Pregnancy enhances antiviral immunity independent of type I IFN but dependent on IL-17–producing γδ + T cells in the nasal mucosa, Science Advances (2024). DOI: 10.1126/sciadv.ado7087

Countertop workers exposed to serious lung disease

Durable and attractive, engineered stone countertops are a popular feature in modern  kitchens, but the workers who build them are risking their health. A growing number of these countertop workers are developing silicosis, a serious and long-term lung disease, according to a study presented at the annual meeting of the Radiological Society of North America (RSNA).

This is a new and emerging epidemic, and we must increase awareness of this disease process so we can avoid delays in diagnosis and treatment for our patients, say the study authors.

Silicosis is caused by the inhalation of crystalline silica dust produced in construction, coal mining and other industries. The prognosis is poor, with gradually worsening lung function leading to respiratory failure. The disease also makes patients more vulnerable to infection in the lungs, chronic obstructive pulmonary disease, autoimmune disease and lung cancer.

In recent years, a resurgence of silicosis has been reported in engineered countertop workers. Engineered stone countertops are made from quartz aggregate held together with a resin binder. They contain substantially more crystalline silica than natural stone versions. Workers who cut, shape, grind and polish these countertops may be exposed to significant amounts of silica dust.

In a preliminary analysis of 21 workers, 100% were male and Hispanic with a median age of 43 years and a median exposure of 18 years. All patients were symptomatic. Patients commonly had atypical and advanced features of silicosis. Shortness of breath and cough were the most common symptoms.

Primary clinicians recognized silicosis at the initial encounter in only four of 21 cases (19%), while radiologists recognized it in seven of 21 cases (33%). Alternative diagnoses, such as infection, were initially suggested in most cases. Nearly half of the patients (48%) had atypical imaging features.

The results highlight a need for more awareness and better recognition of imaging features associated with silicosis.

Source: https://www.rsna.org/annual-meeting

Galleri blood test can  help diagnose multiple forms of cancer

Did you know that the technology to detect more than 50 cancers with one test existed?

Single-cancer screenings are the norm. The focus is usually on three specific cancers in women (breast, colon and cervical) and two in men (prostate and colon). Lung is a focus for heavy smokers.

Screening for these cancers helps save lives. But it creates what Ofman calls a classic spotlight problem, shining the light over there while other, more aggressive cancers go unscreened.

The Galleri test doesn't target a specific area. It looks for the fingerprint, the biological signal in DNA that has been shed from cancer. It's a very specific marker and detects where that cancer is in the body.

It creates a more effective and efficient screening programme.

And unlike other cancer tests (10%) the false positive rate of the Galleri test is just 0.5%.

Source: Medical news

Climate warming is reducing rice quality

Rice is a food staple for billions of people worldwide, with demand doubling over the past 50 years, and is predominantly grown in Asia before being exported globally. This crop is sensitive to weather conditions and, as such, understanding how yields are affected by climate change is of paramount importance to ensure sustainable food supplies into the future.

Beyond yield, the quality of rice may also be affected, determined by a combination of appearance, palatability, nutritional profile and milling properties.

Research published in Geophysical Research Letters, has highlighted a decline in rice quality in  Asia, coincident with changing temperatures.

Researchers used data collected over 35 years to explore patterns in rice quality from Japan and China. This is based upon head rice rate (HRR), which is a measure of the fraction of milled rice kernels that retain 75% of their length after milling, during which the husk and bran are removed.
The research team explored a number of climate variables via modeling to ascertain which had the greatest effect on HRR; these variables were nighttime temperature, daytime temperature, diurnal temperature, daily averaged temperature, hot days (above 30/35 °C), precipitation, precipitation frequency, soil moisture, solar radiation, cloud cover, relative humidity, daytime vapor pressure deficit, transpiration and carbon dioxide concentration.

Ultimately, the scientists determined that overnight temperatures are the main driver of reduced rice quality. In particular, as nighttime temperatures become warmer, a critical threshold for decline begins at 12 °C and 18 °C for Japan and China respectively. When flowering and grain growth occur in such conditions, rates of photosynthesis and starch accumulation in the grain decrease, leading to lower rice quality as more grains are susceptible to breakage.

Part 1

Following this, daily solar radiation was the second most important factor contributing to rice quality changes (higher solar radiation leading to lower HRR), then daily precipitation (less precipitation corresponding to lower HRR) and lastly daytime vapor pressure deficit (beyond a threshold of 0.5–1 kPa, HRR declines).
The average rice quality across all sites and years for China had a HRR of ~62%, but reduced by 1.45% every decade. In Japan, the average HRR was slightly higher at ~66%, with a prominent rate of decline of 7.6% every decade.

In both countries, there is a strong gradient of diminished rice quality from northern to southern provinces and prefectures, likely linked to southern regions being closer to the equator and therefore experiencing higher nighttime temperatures.
This research is important as projections under both moderate and high emissions scenarios suggest rice quality will continue to decline in the decades to come as climate change progresses.
Given all of this, the likelihood of rice cultivars adapting in tandem with the rate of climate change may pose a hazard to sustainable food supplies, human nutrition and economic stability in years to come.

Xianfeng Liu et al, Warming Leads to Lower Rice Quality in East Asia, Geophysical Research Letters (2024). DOI: 10.1029/2024GL110557

Part 2

Countdown to an ice-free Arctic: Research warns of accelerated timelines

The first summer on record that melts practically all of the Arctic's sea ice, an ominous milestone for the planet, could occur as early as 2027.

For the first time, an international research team used computer models to predict when the first ice-free day could occur in the northernmost ocean. An ice-free Arctic could significantly impact the ecosystem and Earth's climate by changing weather patterns. 

The first ice-free day in the Arctic won't change things dramatically, the team says. It will show that we've fundamentally altered one of the defining characteristics of the natural environment in the Arctic Ocean, which is that it is covered by sea ice and snow year-round, through greenhouse gas emissions.

The findings were published Dec. 3 in the journal Nature Communications. Jahn will also present the results on Dec. 9 at the American Geophysical Union annual meeting in Washington D.C.

The researchers' projected/estimated the first ice-free Arctic day using output from over 300 computer simulations. They found that most models predicted that the first ice-free day could happen within nine to 20 years after 2023, regardless of how humans alter their greenhouse gas emissions. The earliest ice-free day in the Arctic Ocean could occur within three years.
It's an extreme scenario but a possibility based on the models. In total, nine simulations suggested that an ice-free day could occur in three to six years.

The researchers found that a series of extreme weather events could melt two million square kilometers or more of sea ice in a short period of time: A unusually warm fall first weakens the sea ice, followed by a warm Arctic winter and spring that prevents sea ice from forming. When the Arctic experiences such extreme warming for three or more years in a row, the first ice-free day could happen in late summer.

Those kinds of warm years have already happened.

But there's also good news: A drastic cut in emissions could delay the timeline for an ice-free Arctic and reduce the time the ocean stays ice-free, according to the study.

Céline Heuzé et al, The first ice-free day in the Arctic Ocean could occur before 2030, Nature Communications (2024). DOI: 10.1038/s41467-024-54508-3 , dx.doi.org/10.1038/s41467-024-54508-3

Seeing through the mystery of an X-ray emissions mechanism

Scientists who study X-rays, lightning and similar phenomena have observed something curious: In lab experiments replicating these occurrences, electrons accelerated between two electrodes can be of a higher energy than the voltage applied.

This defies an assumption in physics that the energy of the electrons should correspond with the voltage applied.

Recently, a team of  researchers used mathematical modeling to explain the underlying mechanism at play. They published their results in Physical Review Letters.

Through mathematical modeling, they  demonstrated that an energy feedback process is responsible for this occurrence.

According to them when the electrons interact with the material of the electrode, they emit X-rays, which are made of photons—massless, charge-less particles that comprise light. Some of these photons propagate backward, enabling more electrons to release from the other electrode.

A small group of these electrons have energy corresponding to the original energy. Then they accelerate again, and the process continues through several cycles. The researchers modeled this very high energy process.

Their model also helped explain why electrodes of different shapes and materials produced this effect to varying degrees. We get maximum effect when we have flat electrodes, and a minimized effect when the electrodes are needle-like. 

This makes sense, because the large surface areas of the flat electrodes are good for the interaction between the electrons and photons and the way they bounce back and forth. When the surface area is reduced, the effect is minimized.

The researchers also examined via simulation and modeling how the phenomenon emerges with different materials.

Tungsten is the standard material used for X-ray production, and we know it's a good material for this. It is a robust material for electron production used in current in X-ray machines.

The researchers said that their findings may be useful for the development of new ways of producing X-rays in the future. Specifically, they said that the work may stimulate new research on the production of energetic electrons from solid materials, potentially making X-rays machines faster and more light weight and compact.

Victor P. Pasko et al, Photoelectric Feedback Mechanism for Acceleration of Runaway Electrons in Gas Discharges at High Overvoltages, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.235301

Toxin in blood of kidney disease patients could contribute to stroke risk, study suggests

Scientists have revealed that a toxin found in the blood of patients with chronic kidney disease (CKD) damages the body's protective blood–brain barrier, likely contributing to the risk of stroke.

Researchers investigated the effect on the central nervous system of "p-cresol sulfate," a molecule produced by the gut microbiome. 

While this molecule is efficiently cleared by the kidneys in healthy people, it accumulates in the blood of patients with CKD.
Investigating the effect of p-cresol sulfate on human tissue and in mice—and replicating their results using blood samples from dialysis patients—the team found that the toxin triggers a process which activates two enzymes that damage the wall of brain blood vessels.

The researchers observed how this impairs the critically protective blood–brain barrier, which acts as a shield to prevent harmful substances and toxins in the body from reaching the brain.

Damage to the blood–brain barrier is known to contribute to the risk of stroke, which can be up to 30 times greater in CKD patients than in the general population.

As part of the study, however, the researchers also found that a class of 'inhibitor' type drugs—which can block chemical reactions in the body—showed promising results in being able to prevent this damage from occurring.

In further tests, the team found that a class of enzyme inhibitor drugs was able to block the damaging effects of blood from CKD patients on cells in vitro.

As well as enhanced stroke risk, patients with CKD, including those not yet requiring dialysis, exhibit significant cognitive decline, a change that seems to be at least partly driven by damage to the brain's blood vessels.

 Sita N. Shah et al, Cerebrovascular damage caused by the gut microbe/host co-metabolite p -cresol sulfate is prevented by blockade of the EGF receptor, Gut Microbes (2024). DOI: 10.1080/19490976.2024.2431651

Research reveals how fructose in diet enhances tumor growth

Fructose consumption has increased considerably over the past five decades, largely due to the widespread use of high-fructose corn syrup as a sweetener in beverages and ultra-processed foods.

New research  shows that dietary fructose promotes tumor growth in animal models of melanoma, breast cancer and cervical cancer. However, fructose does not directly fuel tumors, according to the study published Dec. 4 in the journal Nature.

Scientists discovered that the liver converts fructose into usable nutrients for cancer cells, a compelling finding that could open up new avenues for care and treatment of many different types of cancer.

Using metabolomics—a method of profiling small molecules as they move through cells and across different tissues in the body—the researchers concluded that one way in which high levels of fructose consumption promote tumor growth is by increasing the availability of circulating lipids in the blood. These lipids are building blocks for the cell membrane, and cancer cells need them to grow.

Researchers looked at numerous different cancers in various tissues throughout the body, and they all followed the same mechanism.

Scientists have long recognized that cancer cells have a strong affinity for glucose, a simple sugar that is the body's preferred carbohydrate-based energy source.

In terms of its chemical structure, fructose is similar to glucose. They are both common types of sugar, with the same chemical formula, but they differ in how the body metabolizes them. Glucose is processed throughout the whole body, while fructose is almost entirely metabolized by the small intestine and liver.

Both sugars are found naturally in fruits, vegetables, dairy products and grains. They are also added as sweeteners in many processed foods. 

 The researchers found that added fructose promoted tumor growth without changing body weight, fasting glucose or fasting insulin levels. It had a rather dramatic impact. In some cases, the growth rate of the tumors accelerated by two-fold or even higher.

The researchers attempted to repeat a version of this test by feeding fructose to cancer cells isolated in a dish, the cells did not respond. In most cases they grew almost as slowly as if we gave them no sugar at all.

Part 1

Interestingly, the cancer cells themselves were unable to use fructose readily as a nutrient because they do not express the right biochemical machinery. Liver cells do. This allows them to convert fructose into LPCs, which they can secrete to feed tumors.

Gary Patti, Dietary fructose enhances tumour growth indirectly via interorgan lipid transfer, Nature (2024). DOI: 10.1038/s41586-024-08258-3. www.nature.com/articles/s41586-024-08258-3

Part 2

Serious side effect of using CRISPR-Cas gene scissors uncovered: AZD7648 molecule can destroy parts of genome

Genome editing with various CRISPR-Cas molecule complexes has progressed rapidly in recent years. Hundreds of labs around the world are now working to put these tools to clinical use and are continuously advancing them.

CRISPR-Cas tools allow researchers to modify individual building blocks of genetic material in a precise and targeted manner. Gene therapies based on such gene editing are already being used to treat inherited diseases, fight cancer and create drought- and heat-tolerant crops.

The CRISPR-Cas9 molecular complex, also known as genetic scissors, is the most widely used tool by scientists around the world. It cuts the double-stranded DNA at the exact site where the genetic material needs to be modified. This contrasts with newer gene-editing methods, which do not cut the double strand.

The cut activates two natural repair mechanisms that the cell uses to repair such damage: a fast but imprecise one that reconnects only the ends of the cut DNA, and a slow and precise one that is not activated in every case. The latter requires a copyable template for repair to accurately rejoin the DNA at the cut site.

The slow variant is called homology-directed repair. Researchers want to use this method of repair because it allows the precise integration of individual DNA segments into a desired gene region. The approach is very flexible and can be used to repair different disease genes.

In principle, it could be used to cure any disease.

Part 1

To get the cell to use homology-directed repair, the researchers recently began using a molecule called AZD7648, which blocks fast repair and forces the cell to use homology-directed repair. This approach is expected to accelerate the development of more efficient gene therapies. Initial studies with these new therapies have been good. Too good to be true, as it turned out.

A research group led by Corn has discovered that the use of AZD7648 has serious side effects. The study has been published in the journal Nature Biotechnology.

Although AZD7648 promotes precise repair and thus precise gene editing using the CRISPR-Cas9 system as hoped, in a significant proportion of cells this has led to massive genetic changes in a part of the genome that was expected to be modified without scarring.

The ETH researchers found that these changes resulted in the simple deletion of thousands and thousands of DNA building blocks, known as bases. Even whole chromosome arms broke off. This makes the genome unstable, with unpredictable consequences for the cells edited by the technique.

When the researchers analyzed the genome at the sites where it had been edited, it looked correct and precise. But when they analyzed the genome more broadly, they saw massive genetic changes. These are not seen when you only analyze the short, edited section and its immediate neighborhood.

The extent of the negative effects surprised the researchers. In fact, they suspect that they do not yet have a complete picture of the full extent of the damage because they did not look at the entire genome when analyzing the modified cells, only partial regions.

New tests, approaches and regulations are therefore needed to clarify the extent and potential of the damage.

The development of any new technology is a rocky road. One stumble does not mean we give up on the technology, say the researchers.

Gene therapies based on the CRISPR-Cas system have already been successfully used in clinical practice. In recent years, for example, a hundred patients suffering from the hereditary disease sickle cell anemia have been treated with CRISPR-Cas-based therapeutics—without AZD7648.

"All patients are considered cured and have no side effects".

Grégoire Cullot et al, Genome editing with the HDR-enhancing DNA-PKcs inhibitor AZD7648 causes large-scale genomic alterations, Nature Biotechnology (2024). DOI: 10.1038/s41587-024-02488-6

Part 2

Engineered immune cells to tame inflammation

When the immune system overreacts and starts attacking the body, the only option may be to shut the entire system down and risk developing infections or cancer. But now, scientists  may have found a more precise way to dial the immune system down.

The technology uses engineered T cells that act as immune "referees" to soothe overreacting immune responses. They also can mop up inflammatory molecules.

The new approach could be used to stop the body from rejecting transplanted organs and tissues, such as pancreatic islet cells, which are sometimes used to treat type 1 diabetes. That way, recipients would not need to take harsh immunosuppressant drugs.

This technology can put the immune system back into balance.

The research The team adapted the suppressor cells' anti-inflammatory abilities to work in CD4 immune cells. These are the same cells that are used to make cancer-killing CAR T cells. They also gave these cells a molecular sensor to guide them to their target tissue in the body.

Proof of principle in type 1 diabetes :

The scientists tailored a batch of immune referees to search for human pancreatic islet cells and then produce TGF-Beta and CD25, molecules that can muzzle killer T cells.

They introduced the engineered referee cells into mice that had received a transplant of human islet cells, modeling the treatment for type 1 diabetes.

The referee cells found the vulnerable islet cells and stopped the killer T cells from attacking, and the islet cells survived.

 Nishith R. Reddy et al, Engineering synthetic suppressor T cells that execute locally targeted immunoprotective programs, Science (2024). DOI: 10.1126/science.adl4793. www.science.org/doi/10.1126/science.adl4793

How hummingbirds fly and feed

Scientists explore role of intestinal bacteria in cancer prevention

The link between intestinal bacteria and cancer

Certain intestinal bacteria are found more frequently in some countries such as Norway than in a number of other countries and there is also a higher incidence of bladder cancer, bowel cancer and prostate cancer. These findings may lead to new opportunities for preventing these types of cancer, according to a new study.

Previous studies have shown that a toxin produced by certain bacteria in order to dominate inside the intestine, causes damage to healthy cells and increases the risk of developing bowel cancer.

In a new study, scientists examined the incidence of bladder, colon, rectal and prostate cancer and compared this to the prevalence of two toxin-producing E. coli bacteria in the countries concerned. E. coli is the most common cause of urinary tract infections and bacterial infections in the bloodstream worldwide. Norway has a higher incidence of bladder cancer and colorectal cancer compared with many other countries.

In the course of the study, scientists also found that the prevalence of these two E. coli bacteria was higher in Norway. When they compared equivalent data from several different countries, they discovered a clear pattern: the fewer of these E. coli bacteria that circulate in the population, the lower the incidence of these types of cancer, and vice versa, and the study recently published in The Lancet Microbe confirms this.

In recent years, intense research has been carried out internationally on the link between the toxin produced by these bacteria, called colibactin, and several types of cancer. The research was initiated after groundbreaking studies revealed that colibactin damages DNA in intestinal cells and scientists produced models of intestinal organs and saw that the toxin-producing E. coli resulted in cancer in the models.

Part 1

Scientists have data representing genetic material from 50,000 E. coli samples gathered from four continents. When they studied these, they saw that the ability to produce the toxin is very limited and is primarily found in two particular genotypes of E. coli bacteria. Both of these circulate frequently in Norway and they are also the main genotypes causing infections in the bloodstream in the country.
In contrast, these genotypes of bacteria are rarely found in countries of South Asia.
The scientists involved in this study have therefore put forward a number of hypotheses on which ecological conditions drive these unwanted bacterial families away from certain population groups.
If scientists can succeed in developing vaccines against the harmful type of E. coli that produces colibactin, or a form of probiotics, this would result in notable public health benefits. These measures could eliminate the unwanted colibactin-producing bacteria from the intestines.

Tommi Mäklin et al, Geographical variation in the incidence of colorectal cancer and urinary tract cancer is associated with population exposure to colibactin-producing Escherichia coli, The Lancet Microbe (2024). DOI: 10.1016/j.lanmic.2024.101015. www.sciencedirect.com/science/ … ii/S2666524724002830

Part 2

Genetic risk for schizophrenia linked to a malformed skull

The chromosomal disorder 22q11.2 deletion syndrome (22q) has emerged as one of the strongest risks for schizophrenia. Scientists at St. Jude Children's Research Hospital identified malformed regions of the cerebellum in laboratory models and patients with 22q and found that these malformations were caused by improper skull formation. Further, the researchers linked the skull malformation to the loss of one gene: Tbx1.

The research shows that neurological disorders can stem from sources beyond the nervous system, such as improper skull development. The findings were published today in Nature Communications.

Gene removal blocks skull pocket from forming.

Previous work from scientists found that the deletion of only one 22q gene, Dgcr8, disrupts the flow of auditory information from a lower brain region called the thalamus to the auditory cortex, where sounds are interpreted. This region of the brain is also associated with auditory hallucinations, which are a hallmark symptom of schizophrenia. The researchers called this breakdown in information flow "thalamocortical disruption."

Although thalamocortical disruption occurs late in development, which is consistent with the onset of schizophrenia symptoms, it stays and doesn't go away. However, hallucinations are transient in nature—they come and go.

It seemed that this was just one of the hits that triggered symptoms.

The researchers noticed a part of the brain, the cerebellum, malformed in 22q animal models, specifically, the cerebellum's small lobules called the flocculus and paraflocculus. Most neurodevelopmental disorders arise from defects in genes that play a role in the brain, but the 22q gene the researchers linked to this malformation, Tbx1, was unexpected.

What is interesting about Tbx1 is that it is not very well expressed in the brain, especially the adolescent or adult brain. Rather, it's expressed in the surrounding tissues, namely bone, cartilage and vasculature tissues. It is very unlikely that Tbx1 directly affects the brain at all.

Instead, removing Tbx1 has an indirect but significant effect on brain development. Bone formation relies on immature osteoblast cells correctly growing into mature osteocytes. Tbx1 removal disrupted this cycle, resulting in an underdeveloped pocket in the skull which normally houses the flocculus and paraflocculus.

For a neurological syndrome, the findings are strikingly unusual—with no pocket in the skull for these structures to develop, they appear substantially smaller than normal. The reduction of the flocculus and paraflocculus was validated through magnetic resonance imaging studies of dozens of patients with 22q and a comparative control group.

Part 1

Researchers studied the flocculus and paraflocculus' role in the brain to better understand how their malformation could influence behavior. They found that the neural circuits within the flocculus and paraflocculus are dysfunctional.
The regions also control a reflex that ensures stable vision during head movements and is crucial for face recognition. The researchers found that this reflex is impaired in 22q. This may be a valuable lead for schizophrenia research because patients with schizophrenia have a deficit in face recognition.
The paraflocculus is also connected to the auditory cortex.

Tae-Yeon Eom et al, Tbx1 haploinsufficiency leads to local skull deformity, paraflocculus and flocculus dysplasia, and motor-learning deficit in 22q11.2 deletion syndrome, Nature Communications (2024). DOI: 10.1038/s41467-024-54837-3

Part 2

Researchers reprogram immune cells to decrease rejection of medical implants

Researchers have discovered that using a drug that is a metabolic inhibitor  makes the body more receptive to medical devices such as pacemakers, replacement joints and dental implants.

When doctors surgically place an implant into a human, there will always be an immune response and there's a chance the implant will be rejected.

Scientists used a drug that signals the body to boost or inhibit a particular reaction, called a metabolic modulator. This drug was incorporated into an amorphous polylactide—a biomaterial used to make medical implants—and then the material was implanted in mice.

Using intravital microscopy—a technique that allows us to look inside a living subject under a microscope—the researchers imaged different kinds of immune cells around the implant site for up to 10 weeks.

Their paper is published in the journal Nature Biomedical Engineering.

These findings have significant implications for improving patient recovery times, reducing postsurgical complications like chronic inflammation and implant rejection and potentially saving costs. And they may eventually affect the way medical device manufacturers and pharmaceutical scientists approach medical implants.

Chima V. Maduka et al, Immunometabolic cues recompose and reprogram the microenvironment around implanted biomaterials, Nature Biomedical Engineering (2024). DOI: 10.1038/s41551-024-01260-0

Does CPR help both the conditions of cardiac arrest and heart attacks?

Quality of parent-child relationships predicts adulthood well-being

The link between early life experiences and mental health has been widely explored by psychology researchers. One key aspect of human early life experiences is the relationship that people develop with their parental figures, which is at the center of attachment theory and various other psychological models.

Past studies suggest that the quality of relationships between parents and their children plays a role in the subjective well-being of these children when they reach adulthood. While this finding is well-documented, many past studies were conducted on relatively small samples of participants residing in a single country.

The countries included in this study were selected carefully, to maximize religious and ethnic diversity in the sample. The objective was to include people living in all the broader geographical regions on Earth.

Now two researchers at Gallup, recently carried out a study aimed at exploring the link between parent-child relationships and an adult's self-reported well-being in a larger and more varied sample that spanned across 21 countries.

Their paper, published in Communications Psychology, suggests that the quality of parent-child relationships predicts the well-being of adults residing in all of the countries they studied.

The researchers  found a substantial effect of parent-child relationships on both flourishing and mental health. The effect was larger than any other variable they tested, including parental socio-economic status, current education level, current household income, gender, and financial security.

The relationship was positive in every country, and it reached conventional levels of significance in all but one. Even that exception seemed to be explained by the relatively young population in the survey. When the researchers re-weighted the data to make the ages similar across countries, they found a significant effect in every country.

Overall, the findings of this research study suggest that there is a universal link between parent-child relationships and lifelong well-being, which applies to all people, irrespective of where they were raised.

 Jonathan T. Rothwell et al, Parent-child relationship quality predicts higher subjective well-being in adulthood across a diverse group of countries, Communications Psychology (2024). DOI: 10.1038/s44271-024-00161-x.

Meta-analysis of current global warming impacts suggests a third of all species could be extinct by 2100

Biologists found evidence that up to a third of all species alive today could go extinct by 2100 if greenhouse gas emissions are not slowed or stopped. In his study published in the journal Science, they conducted an analysis of 485 studies carried out over the past 30 years on the ability of species to adapt to climate change.

Manmade greenhouse gas emissions are causing atmospheric and seawater warming, and these temperature increases will lead to unpredictable weather changes—besides growing warmer, it is expected that some places will grow wetter and others drier. It is also likely that the world will see more extreme weather, such as droughts, hurricanes and typhoons, in addition to thunderstorms or snow storms. Such changes will put pressure on species that are not able to control their environment the way humans do, putting many at risk.

Part 1

In this new effort, researchers found 485 papers that involved the study of a species and its ability to survive changes to its environment. They then compared this data with estimates of future warming and determined what sort of changes might occur and in which areas. They then made estimates about the likely survivability of a given species based on where it lives and its ability to migrate or to adapt.

The researchers found that if global temperatures rise approximately 5.4°C by the end of this century (the worst-case scenario), it would likely lead to the extinction of approximately one-third of all species alive today. They note that some cases of chain-reaction extinctions could occur, in which a small animal goes extinct and then a larger animal that feeds on it consequently goes extinct. They also note that some species groups or types are at much higher risk than others, such as amphibians.

Mark C. Urban, Climate change extinctions, Science (2024). DOI: 10.1126/science.adp4461

Part 2

Scientists make cooking oil biofuel as efficient as diesel

A new way to produce fuels made from leftover fat can create biofuel as effective as diesel and 1000-times more efficiently than current methods, a new study has suggested.

Published in Green Chemistry, researchers  used enzymes to break down fatty acids in cooking oil into alkenes, the building block of fuels like petrol and diesel.  The scientists hope that the new renewable fuel, which can be made using leftover food waste, can cut fossil fuel usage.

Biofuels are a wide variety of energy sources made from renewable organic material that comes from plants or animals, like vegetable oil. Those that can directly replace petrol or diesel in conventional combustion engines have been touted as a sustainable alternative to fossil fuels, with fuels derived from food waste cutting greenhouse gases by up to 94%.

Typically, these fuels contain a lot of oxygen molecules which burn inefficiently. This low fuel efficiency has previously prevented widespread usage with the energy produced by burning fatty acid derived biofuels being 90% of that produced by diesel. To compensate and create diesel equivalents more raw materials are needed, pushing up costs to two times that of fossil fuels.

To create a more efficient fuel with more active alkene in, the researchers modified an enzyme called P450 decarboxylase to break down fatty acids found in food waste and extract the oxygen found within.
The enzyme typically requires water to work, meaning that it produces a low yield of alkene. To overcome this, the modified enzyme was placed in a liquid salt while a UV light was shone on it as it mixed with fatty acids to activate the reaction. This resulted in a yield of alkenes that was far greater than what is possible in water. The improved efficiency means that the production of the fuel requires less energy and lower amounts of raw materials, dramatically improving sustainability.

Moreover, as the enzyme is a biological catalyst, the process removes the need for conventional catalysts like platinum, which avoids any environmental damage caused by mining. The use of UV light also prevents the use of toxic chemicals like hydrogen peroxide to push the reaction forward.

Jake H. Nicholson et al, Enhancing the reactivity of a P450 decarboxylase with ionic liquids, Green Chemistry (2024). DOI: 10.1039/D4GC05292G

AI infiltrates the rat world: New robot can interact socially with real lab rats

When police make 500 arrests using facial recognition tech, can we say "our privacy and freedom are being infringed upon"?

London's Metropolitan Police force said this week that it had used facial recognition technology to make more than 500 arrests in 2024 for offenses ranging from shoplifting to rape.

The force uses live facial recognition in specific areas of the UK capital, positioning a van equipped with cameras in a pre-agreed location.

The cameras capture live footage of passers-by and compare their faces against a pre-approved watchlist, generating an alert if a match is detected.

Civil liberties campaigners have criticized the use of such technology, and advocacy group Big Brother Watch has launched legal action to stop its expansion.

"The technology works by creating a 'faceprint' of everyone who passes in front of camera—processing biometric data as sensitive as a fingerprint, often without our knowledge or consent," the group says on its website.

"This dangerously authoritarian surveillance is a threat to our privacy and freedoms—it has no place on the streets of Britain," it adds.

The Met says it is a "forerunner" in using the technology, adding that it helps "make London safer" by helping detect "offenders who pose significant risks to our communities".

Of the 540 arrests, more then 50 were for serious offenses involving violence against women and girls, including offenses such as strangulation, stalking, domestic abuse and rape

( My questions : don't these crimes severely  infringe upon our freedom and privacy? Don't they put all the women in dangerous situations?).

More than 400 of those arrested have already been charged or cautioned.

"This technology is helping us protect our communities from harm", say the police. Can you argue against it?

This tech is a powerful tool that supports officers to identify and focus on people who present the highest risk that may otherwise have gone undetected. 

Responding to privacy fears, police said that the biometric data of any passer-by not on a watchlist is "immediately and permanently deleted".

Can you get an assurance better than that?

I am okay with this tech. Because I am not a criminal and don't do anything against the law, ever. Then why should I be afraid of it?

It is much better than 500 criminals roaming around the streets.

Police, keep it coming. I am all game for it.

Source: News agencies 

Molecular 'ZIP code' draws killer T cells to brain tumors

Scientists have developed a "molecular GPS" to guide immune cells into the brain and kill tumors without harming healthy tissue.

It is the first living cell therapy that can navigate through the body to a specific organ, addressing what has been a major limitation of CAR-T cancer therapies until now. The technology worked in mice and the researchers expect it to be tested in a clinical trial next year.

Working in mice, the scientists showed how the immune cells could eliminate a deadly brain tumor called glioblastoma—and prevent recurrences. They also used the cells to tamp down inflammation in a mouse model of multiple sclerosis.

Because of their location, brain cancers are among the hardest cancers to treat. Surgery and chemotherapy are risky, and drugs can't always get into the brain.

To get around these problems, the scientists developed a "molecular GPS" for immune cells that guided them with a "zip code" for the brain and a "street address" for the tumor.

Part 1

They found the ideal molecular zip code in a protein called brevican, which helps to form the jelly-like structure of the brain, and only appears there. For the street address, they used two proteins that are found in most brain cancers.

The scientists programmed the immune cells to attack only if they first detected brevican and then detected one or the other of the brain cancer proteins.

When the scientists put the immune cells into the bloodstream, they easily navigated to the mouse's brain and eliminated a growing tumor. Any immune cells that remain in the bloodstream stay dormant, sparing any tissues outside the brain that happen to have the same protein "address" from being attacked.

One hundred days later, the scientists introduced new tumor cells into the brain, and enough immune cells were left to find and kill them, a good indication that they may be able to prevent any remaining cancer cells from growing back.

"The brain-primed CAR-T cells were very, very effective at clearing glioblastoma in our mouse models, the most effective intervention we've seen yet in the lab", say the scientists.
In another experiment, the researchers used the brain GPS system to engineer cells that deliver anti-inflammatory molecules to the brain in a mouse model of multiple sclerosis. The engineered cells once again reached their target and made their delivery, and the inflammation faded.

The scientists hope this approach will soon be ready for patients with other debilitating nervous system diseases.

Milos S. Simic et al, Programming tissue-sensing T cells that deliver therapies to the brain, Science (2024). DOI: 10.1126/science.adl4237

Part 2

Many women with epilepsy unaware of seizure meds' risks to pregnancy

Many women with epilepsy who are of childbearing age might not realize their anti-seizure drugs can raise the risk of birth defects or dampen the effectiveness of their birth control, a new study warns.

Likewise, some birth control methods can cause anti-seizure meds to be less effective, researchers reported this week in a presentation at the annual meeting of the American Epilepsy Society in Los Angeles.

Many neurologists do not learn about birth control in their training, even though they know that anti-seizure medications may have some risks in pregnancy. 

This study raises awareness for patients and encourages health care providers from neurology and reproductive health care to work together to ensure the best care for these patients.

Part 1

For the study, researchers surveyed 107 women ages 18 to 49 who were taking anti-seizure medications about their reproductive plans.

Six said they were pregnant or planning to become pregnant, and another 69 said they were using some sort of birth control that could interfere with their anti-seizure meds, researchers said.
Survey participants may not have known that their answers were wrong and so did not feel they needed more information," Betstadt noted.

Only about a third of the women were receiving medical care that aligned with their reproductive plans, researchers found.

Anti-seizure medications that increase the risk of birth defects include valproic acid, topiramate, carbamazepine, phenobarbital and phenytoin.

Further, anti-seizure drugs that can make hormonal contraceptives like pills, patches and rings less effective include carbamazepine, phenytoin, phenobarbital, and higher doses of topiramate and oxcarbazepine.

Despite that, no anti-seizure drug is as dangerous for an expecting mother or her fetus as uncontrolled seizures, the researchers noted.

Women who want to become pregnant should talk with their doctor about drugs that are less risky but still can control their seizures, researchers said.

The survey quizzed women on their knowledge regarding birth control and anti-seizure meds, and found that:

Two-thirds (67%) of all the women answered at least one question incorrectly regarding the ways birth control can interfere with anti-seizure medications and vice-versa
56% of those who want to become pregnant answered at least one question incorrectly about the birth defect risk posed by anti-seizure drugs
36% of those actively using birth control showed some ignorance of the way it can interact with anti-seizure meds
73% felt they didn't need any more education about these risks
Only 29% of those who displayed any ignorance of the interaction said they wanted more education.
Neurology and reproductive health care providers should collaborate to provide the safest and most effective care for their patients of reproductive age who are taking anti-seizure medications

Source: https://www.epilepsy.com/lifestyle/family-planning/birth-control

A Beneficial Bacterium Helps Wounds Heal

A bacterium found in the wound microbiome can accelerate healing, highlighting the potential for microbiota-based wound therapies.

Skin wounds that fail to heal in a normal timeframe are considered to be chronic, and an estimated two percent of the global population will experience a chronic wound in their lifetime. In addition to severe pain, individuals with chronic wounds can face mental health problems due to the persistent nature of the condition and the risk of recurrence. This significantly affects their quality of life, highlighting the need for effective treatments.

Given this unmet clinical need, researchers have been exploring a new frontier—the wound microbiome. Previously published studies have largely focused on faulty processes in skin cells that contribute to impaired healing. But recently, researchers have appreciated that there is a wound microbiome—an entire ecosystem that colonizes wounds and can influence wound healing.
Highlighting this, researchers have shown that a bacterium found in chronic wounds can aid wound healing in mice. The results, published in Science Advances, uncover a mechanism of bacterial-driven wound repair and provide a foundation to develop microbiome-based therapies.
This study is unique in terms of bringing light on the good part of the chronic wound microbiome.‌

White EK, et al. Alcaligenes faecalis corrects aberrant matrix metalloproteinase expression to promote r.... Sci Adv. 2024;10(26):eadj2020. 

To identify chronic wound-associated microbiota, the researchers swabbed diabetic foot ulcers from 100 participants and sequenced DNA from these samples. Among the bacteria abundantly present in the samples, they identified an environmental, non-pathogenic bacterium called Alcaligenes faecalis. Digging into published datasets, the team found that this bacterium was prevalent in different types of chronic wounds, such as pressure ulcers and venous leg ulcers. This prompted them to investigate the role of A. faecalis in chronic wounds.

For their experiments, the team used a diabetic mouse model that exhibits impaired wound healing. They made wounds measuring about eight millimeters in diameter on the back skin of these mice and treated them with A. faecalis culture. They photographed these wounds at different times and observed that wounds colonized with A. faecalis were significantly smaller than wounds treated with a control solution. To better understand how A. faecalis influences wound healing, the researchers used in vitro assays to investigate whether the bacterium promoted cell migration, a crucial process that occurs in the outer skin layer during the early stages of wound healing. They isolated keratinocytes, cells from the outermost layer of the skin, from diabetic mice and cultured them in lab dishes. Once the cells had formed a layer in the dish, the researchers introduced a thin scratch along the middle, disrupting the continuous layer of cells. They treated the system with either A. faecalis or a control solution and took photographs over time to track how quickly cells from the undisturbed side moved toward the scratch to fill the empty space. Compared to control-treated cells, A. faecalis treatment increased the rate at which keratinocytes migrate. They observed similar results when they repeated this experiment with skin cells obtained from people with diabetes, indicating that the bacterium likely influences wound healing in humans via a similar mechanism.

The results show that we need to think about how to retain friendly bacteria while using less aggressive antimicrobial approaches to eliminate pathogens from the chronic wound environment, say the researchers.

Just taking antibiotics blindly could eliminate these useful bacteria that help in the wound healing process. 

Kalan LR, et al. Strain- and species-level variation in the microbiome of diabetic w.... Cell Host Microbe. 2019;25(5):641-655.e5. 

Part 2

Scientists produce world's first carbon-14 diamond battery with potential lifespan of thousands of years

Scientists and engineers have successfully created the world's first carbon-14 diamond battery.

This new type of battery has the potential to power devices for thousands of years, making it an incredibly long-lasting energy source. The battery leverages the radioactive isotope, carbon-14, known for its use in radiocarbon dating, to produce a diamond battery.

Several game-changing applications are possible. Bio-compatible diamond batteries can be used in medical devices such as ocular implants, hearing aids, and pacemakers, minimizing the need for replacements and distress to patients.

Diamond batteries could also be used in extreme environments—both in space and on earth—where it is not practical to replace conventional batteries. The batteries could power active radio frequency (RF) tags where there is a need to identify and track devices either on Earth or in space, such as spacecraft or payloads, for decades at a time, thus reducing costs and extending operational lifespan.

The carbon-14 diamond battery works by using the radioactive decay of carbon-14, which has a half-life of 5,700 years, to generate low levels of power. It functions similarly to solar panels, which convert light into electricity, but instead of using light particles (photons), they capture fast-moving electrons from within the diamond structure.

Diamond batteries offer a safe, sustainable way to provide continuous microwatt levels of power. 

I received this from RG centre for Biotechnology, Thiruvananthapuram, Kerala, (Biotechnology and disease Biology, Ministry of Science and Technology, Dept. of Biotechnology, Government of India) requesting me to share it with the general public :

Dr. Jackson James who headed the team from BRIC-Rajiv Gandhi Centre for Biotechnology (RGCB) which came up with the finding that gene mutation can cause autism.

Gene mutation likely cause for developing autism in early childhood: RGCB study

Thiruvananthapuram, Dec. 09: Autism, a developmental disorder that causes functional abnormalities in brain development, is caused by a combination of environmental and genetic factors with its symptoms manifesting in childhood as early as the age of two years. Complexities of ASD (Autism Spectrum Disorder) include single gene mutations in early development genes.

A recent RGCB study linked a novel mutation in Tlx3 gene with abnormal development of the cerebellum (a major region of the hind brain that controls balance, motor movement, and other complex functions) and autism.

The study, conducted by Dr. Jackson James and his team from BRIC-Rajiv Gandhi Centre for Biotechnology (RGCB) here, has been published in the prestigious journal iScience.

Deleting Tlx3 gene from the cerebellum of a transgenic mouse (a mouse with its DNA altered through genetic engineering techniques) embryo potentially affects coordination of cerebellum function. When these mice embryos were allowed to grow until adulthood, they developed hallmarks of autistic behavior, including abnormalities in social skills, repetitive behaviour, and motor/movement function.

The RGCB team, in collaboration with CSIR-IGIB (Council Of Scientific And Industrial Research–Institute Of Genomics And Integrative Biology (CSIR–IGIB), New Delhi, also assessed the potential for this mutation to occur in the human population and identified TLX3 mutation variants that are linked to nine ASD cases and other co-morbid neurodevelopmental conditions.

Dr. James, however, stated that a genome-wide global cohort analysis is necessary to assess the frequency of this TLX3 mutation and the extent to which the variation is linked to specific populations, such as Indians and others. Together, these results indicate how erroneous regulation of this early embryonic gene manifests into ASDs during early childhood.

RGCB Director Prof. Chandrabhas Narayana said, “Autism is a serious childhood problem across the world. In India also, it has emerged as a significant challenge for researchers and medical fraternity as autism has wide social and medical ramifications. The RGCB study will offer new insights into this behavioural disorder.”

ASDs lead to behavioural deficits, including lack of social cognition and restricted/repetitive behaviours, desires, communication, or actions in individuals.

A technosignature that could detect an extraterrestrial civilization's reliance on nuclear fusion

Extraterrestrial civilizations need a great deal of energy as they advance up the Kardashev scale. Fossil fuels are finite, wind and solar energy are carbon free but not as efficient as fossil fuels, and traditional nuclear fission power depends on a supply of fissionable material and has a waste problem. Thus, any advanced alien species may well turn to nuclear fusion for their ever-increasing energy needs (unless they've discovered even better energy processes we don't yet know about).

Deuterium (D) fusion is one of the simplest forms of nuclear fusion, where D fuses with tritium or another D. As life needs water as far as we know, oceans on an advanced world could supply plenty of it in ocean water.
On Earth, water contains a natural miniscule amount of heavy water, with deuterium replacing one or both hydrogen atoms to exist as HOD or DOH and rarely as D2O. Extracting deuterium from an ocean would decrease its ratio of deuterium-to-hydrogen, D/H, including in atmospheric water vapor, while the helium produced in the nuclear reactions would escape to space. Could low values of D/H in an exoplanet's atmosphere be a technosignature of long-lived, uber-advanced extraterrestrial life?

Measuring the D/H ratio in water vapor on exoplanets is certainly not a piece of cake, though. It is not impossible either. 

One big advantage of looking for low D/H values in an exoplanet's atmosphere is that it would persist even if advanced life died out on their planet or migrated away, increasing the chances of detecting this technosignature.

Part 1

On Earth, where humanity is currently at 0.73 on the Kardashev scale, natural deuterium in the ocean accounts for about one atom in every 6,240 atoms of hydrogen, or 35 grams of deuterium for every ton of seawater. (That's a collective 4.85 × 1013 tons of deuterium.) The D/H ratio is nearly the same in our atmosphere. Deuterium can fuse with itself and, in a chain of nuclear reactions, ultimately produces 335 gigajoules of energy per gram of deuterium.

Using Earth as a model for an exoplanet with advanced life, researchers calculated fusion power of roughly 10 times that projected for humans next century, about 100 TW in 2100 for a population of 10.4 billion (five times more than today). That 1,000 terawatts (TW)—which could be a low amount for an advanced species (or their robotic descendants!)—would deplete an Earth-like ocean's D/H value to a value found in the local interstellar medium, about 16 parts per million, in about 170 million years.

If the D/H ratio in the water of an exoplanet was found to be substantially below [interstellar medium] values...it would be strange and anomalous," the researchers write in their paper.
If, by chance, their exoplanet had an ocean only a few percent of Earth's—a so-called "land planet"—D/H would reach anomalously low values in roughly 1 to 10 million years. That's on the order of the average lifetime of a mammalian species since the Chicxulub impact ended the dinosaurs, about 3 million years.
Other planets have higher D/H values, like Venus and Mars, but processes like Venus's runaway greenhouse effect and physical escape processes on Mars have left both uninhabitable. Thus a higher D/H than Earth's "probably indicates a planet that is problematic for habitability on geologic timescales."

Calculations like these led the group to propose looking for unusually low D/H in planetary water vapor as a potential technosignature, which they call "potentially remotely detectable."
Part 2

Using the Spectral Mapping Atmospheric Radiative Transfer (SMART) model, they proposed specific wavelengths to look for among the emission lines for of HDO and H2O. HDO has strong lines in the infrared and near-infrared part of the electromagnetic spectrum, and in 2019 scientists first detected water vapor in the atmosphere of a potentially habitable planet.

Two missions in development, NASA's Habitable Worlds Observatory (HWO) that would follow the James Webb Space Telescope, and the European-led Large Interferometer For Exoplanets (LIFE), could possibly measure D/H.

It's up to the engineers and scientists designing [HWO] and [LIFE] to see if measuring D/H on exoplanets might be an achievable goal.
Looking for D/H from LIFE appears to be feasible for exoplanets with plenty of atmospheric water vapor in a region of the spectrum around 8 microns wavelength, say the researchers.

David C. Catling et al, Potential technosignature from anomalously low deuterium/hydrogen (D/H) in planetary water depleted by nuclear fusion technology, arXiv (2024). DOI: 10.48550/arxiv.2411.18595

Part 3

Blue-throated macaws have advanced motor imitation capabilities, study shows

Blue-throated macaws, a critically endangered parrot species, have demonstrated automatic imitation of intransitive (goal-less) actions—a phenomenon previously documented only in humans.

In a study conducted by an international team of researchers, scientists reveal that macaws involuntarily copy intransitive movements.

This finding, in addition to the well-known vocal mimicry skills of parrots, highlights their remarkable motor imitation abilities. The research also suggests the possibility of a mirror-neuron system in parrots, akin to that found in humans.

Imitation of goal-less intransitive actions is a cornerstone of human cultural evolution. A large part of human culture comprises the transmission of technical skills, usually involving tools. Another substantial part is the learning of cultural conventions, which encompasses high-fidelity copying of gestures or movements and fosters social bonding and prosocial behaviors.

Previous studies have shown that humans mimic gestures involuntarily—what is known as automatic imitation. Until now, evidence of such automatic imitation in non-human animals was limited to transitive (object-directed) actions, such as grasping objects, as observed in dogs and budgerigars.

In their study, now published in iScience, the researchers trained macaws to perform two distinct actions ("lift leg" and "spread wings") in response to specific hand signals. Birds were then divided into two groups: Macaws in the compatible group received a reward when they mimicked the action of another macaw (demonstrator). Birds in the incompatible group received a reward when they did not imitate the action, but performed exactly the opposite one.

The incompatible group struggled to suppress their automatic tendency to mimic the demonstrator's action. This resulted in more incorrect responses and longer reaction times compared to the compatible group.

The findings are remarkable because they show, for the first time, a non-human animal involuntary imitation of intransitive actions.

In humans, this behavior is linked to neural circuits involving mirror neurons, which activate during both the observation and execution of the same action. While this study does not directly prove the presence of mirror neurons in parrots, it strongly suggests their involvement in motor imitation.

 Esha Haldar et al, Automatic imitation of intransitive actions in macaws, iScience (2024). DOI: 10.1016/j.isci.2024.111514

Scientists discover more mitochondria-like symbionts with surprising metabolic capacities

In 2021, scientists at the Max Planck Institute for Marine Microbiology in Bremen, Germany, reported an astonishing new form of symbiosis: They found a unique bacterium that lives inside a ciliate—a unicellular eukaryote—and provides it with energy. The symbiont's role is thus strongly reminiscent of mitochondria, with the key difference that the endosymbiont derives energy from the respiration of nitrate, not oxygen.

Now the researchers  set out to learn more about the environmental distribution and diversity of these peculiar symbionts.

The scientists set out to look for molecular signatures of the symbiont in huge public sequencing databases, which contain vast amounts of genetic data from all kinds of environmental samples. And indeed, they detected these symbionts in about 1,000 different datasets.

The scientists were surprised how ubiquitous they are. They could find them on every inhabited continent. They learned  that they can live not only in lakes and other freshwater habitats but also in groundwater and even wastewater.

The scientists discovered not only the original symbiont in these datasets, but also some new close relatives.

The scientists  were in for another surprise—these respiratory symbionts can do new tricks. 

Unlike the original symbiont species, which can only perform anaerobic respiration (i.e., denitrification), all new symbiont species actually encode a terminal oxidase—an enzyme that enables them to also respire oxygen in addition to nitrogen. This can explain why we find these symbionts also in environments that are fully or partially toxic.

Daan R. Speth et al, Genetic potential for aerobic respiration and denitrification in globally distributed respiratory endosymbionts, Nature Communications (2024). DOI: 10.1038/s41467-024-54047-x

Particle that only has mass when moving in one direction observed for first time

For the first time, scientists have observed a collection of particles, also known as a quasiparticle, that's massless when moving one direction but has mass in the other direction. The quasiparticle, called a semi-Dirac fermion, was first theorized 16 years ago, but was only recently spotted inside a crystal of semi-metal material called ZrSiS. The observation of the quasiparticle opens the door to future advances in a range of emerging technologies from batteries to sensors, according to the researchers.

The researchers  recently published their discovery in the journal Physical Review X.

A particle can have no mass when its energy is entirely derived from its motion, meaning it is essentially pure energy traveling at the speed of light. For example, a photon or particle of light is considered massless because it moves at light speed. According to Albert Einstein's theory of special relativity, anything traveling at the speed of light cannot have mass.

In solid materials, the collective behavior of many particles, also known as quasiparticles, can have different behavior than the individual particles, which in this case gave rise to particles having mass in only one direction.

The team's analysis showed the presence of semi-Dirac fermions at the crossing points. Specifically, they appeared massless when moving in a linear path but switched to having mass when moving in a perpendicular direction.

Semi-Dirac fermions were first theorized in 2008 and 2009 by several teams of researchers, including scientists from the Université Paris Sud in France and the University of California, Davis. The theorists predicted there could be quasiparticles with mass-shifting properties depending on their direction of movement—that they would appear massless in one direction but have mass when moving in another direction.

Sixteen years later, researchers accidentally observed the hypothetical quasiparticles through a method called magneto-optical spectroscopy. The technique involves shining infrared light on a material while it's subjected to a strong magnetic field and analyzing the light reflected from the material.

Part 1

The team conducted their experiments at the National High Magnetic Field Laboratory in Florida. The lab's hybrid magnet creates the most powerful sustained magnetic field in the world, roughly 900,000 times stronger than the Earth's magnetic field. The field is so strong it can levitate small objects such as water droplets.

The researchers cooled down a piece of ZrSiS to -452°F—only a few degrees above absolute zero, the lowest possible temperature—and then exposed it to the lab's powerful magnetic field while hitting it with infrared light to see what it revealed about the quantum interactions inside the material.
When a magnetic field is applied to any material, the energy levels of electrons inside that material become quantized into discrete levels called Landau levels.
The levels can only have fixed values, like climbing a set of stairs with no little steps in between. The spacing between these levels depends on the mass of the electrons and the strength of the magnetic field, so as the magnetic field increases, the energy levels of the electrons should increase by set amounts based entirely on their mass—but in this case, they didn't.

Using the high-powered magnet in Florida, the researchers observed that the energy of the Landau level transitions in the ZrSiS crystal followed a completely different pattern of dependence on the magnetic field strength. Years ago, theorists had labeled this pattern the "B2/3 power law," the key signature of semi-Dirac fermions.

Yinming Shao et al, Semi-Dirac Fermions in a Topological Metal, Physical Review X (2024). DOI: 10.1103/PhysRevX.14.041057
Part 2

AI's power demands driving toxic air pollution, study finds

Computer processing demands for artificial intelligence, or AI, are spurring increasing levels of deadly air pollution from power plants and backup diesel generators that continuously supply electricity to the fast-growing number of computer processing centers.

This air pollution is expected to result in thousands of premature deaths a year by 2030.

Total public health costs from cancers, asthma, other diseases, and missed work and school days are getting mind boggling. 

Such are findings of a study by UC Riverside and Caltech scientists published online this week on the arXiv preprint server. Yet, these human and financial costs appear overlooked by the tech industry.

Yuelin Han et al, The Unpaid Toll: Quantifying the Public Health Impact of AI, arXiv (2024). DOI: 10.48550/arxiv.2412.06288

What happens in the ocean when two cyclones collide?

In April 2021, two tropical cyclones, Seroja and Odette, collided in the Indian Ocean northwest of Australia. Researchers   now studied how this rare phenomenon affected the ocean.

According to their case study, the rendezvous caused an unusual cooling of the surface water and an abrupt change in the direction of the combined storm. Since the frequency and intensity of tropical cyclones are increasing as a result of global warming, it is possible that such encounters—and thus more extreme air-sea interactions—will become more frequent in the future, they conclude.

Tropical cyclones (TCs) not only whip up air masses in the atmosphere, they also churn up water masses in the areas of the ocean that are in their path. When two cyclones collide and merge, these interactions between the ocean and the atmosphere can intensify considerably.

Researchers reported this  in a paper published in the journal Tellus A: Dynamic Meteorology and Oceanography.

The researchers analyzed the encounter between two relatively weak tropical cyclones in the Indian Ocean in 2021, TC Seroja and TC Odette, and found that effects occurred that have otherwise only been observed with much stronger cyclones. Since the frequency and intensity of tropical cyclones is increasing as a result of global warming, this type of convergence—and the resulting extreme interactions between air and sea—could become more frequent in the future, the study concludes.

Researchers combined satellite data and measurements obtained from ARGO floats and autonomous drifters with numerical modeling. These sources provided the researchers with information about factors such as salinity and water temperatures between the sea surface and depths of up to 2,000 meters as well as data about upward and downward (vertical) flow velocities. In addition to these data, they analyzed upward and downward (vertical) flow velocities using data from numerical models. 

The encounter between the two cyclones lasted for around a week. On 6 April they came within approximately 1,600 kilometers of one another. Seroja first of all stalled the smaller cyclone Odette and then merged with it three days later.

After the two cyclones merged, TC Seroja abruptly changed course by 90 degrees on 9 April. This chain of events not only influenced weather patterns but also triggered a previously unobserved interaction with the ocean underneath.

Part 1

The analysis showed that sea-surface temperatures dropped by 3°C as an after-effect of the merging of the cyclones, and deep, cold water masses were churned upwards towards the surface from a depth of 200 meters in a process known as "upwelling." The cooling effect was "exceptionally high" in relation to the cyclones' intensity, the researchers observed.

The highest wind speeds of around 130 kilometers per hour were reached on 11 April, after the merging of the cyclones, and corresponded to Category 1 on the Hurricane Scale. The observed cooling and the depth of the upwelling, on the other hand, were of a scale observed in Category 4 or 5 hurricanes.
The researchers were particularly surprised by the strength of the upwelling: there were periods when the deep-water masses rose to the sea surface at a speed of up to 30 meters per day. By comparison, the typical upward velocity of the ocean is only between 1 and 5 meters per day.

In this specific case, a downward velocity of the ocean was observed shortly before the cyclones merged. Thanks to satellite technology and autonomous deep-sea ARGO floats, they were able to demonstrate how the rotation of the cyclones transports cold water from the depths of the ocean to the surface.
Although encounters between tropical cyclones during their one to two-week lifespan have been rare to date, according to climate models, the number and intensity of tropical cyclones is likely to increase as a result of global warming—and by extension also the likelihood of full-blown hurricane-force cyclones colliding.
This could result in "the most extreme interactions between the ocean and the atmosphere," the authors of the paper write. The fact that the merging of two cyclones can lead to an abrupt change of course also makes it more difficult to predict how they will behave afterwards.
They also point to another important consequence: "As a result of the interactions of a cyclone with the ocean and the upwelling of cold, deep water, the ocean absorbs additional heat from the air and then transports it to higher latitudes—a crucial process that influences the climate worldwide."
In addition, cyclones also convert thermal energy into mechanical energy which they then transport to higher latitudes as they progress.

Oliver Wurl et al, Intense Cooling of the Upper Ocean with the Merging of Tropical Cyclones: A Case Study in the Southeastern Indian Ocean, Tellus A: Dynamic Meteorology and Oceanography (2024). DOI: 10.16993/tellusa.4083

New antidote could save lives from deadly hydrogen sulfide gas

Hydrogen sulfide, a colorless gas that smells like rotten eggs, is produced naturally from decaying matter. This gas is lethal to breathe in, and hydrogen sulfide present in high concentrations can cause death very rapidly.

Its relative density is also greater than air, causing it to accumulate at lower altitudes and posing an enormous threat to workers at sites, such as manholes, sewage systems and mining operations.

Why is hydrogen sulfide so dangerous? It binds strongly to the heme-containing cytochrome c oxidase (CcO) enzyme and blocks the cellular process of aerobic (oxygen-dependent) respiration.
What is even more concerning is that, as of now, there is no identified antidote that can treat hydrogen sulfide poisoning. Hence, there is an urgent need to develop therapeutic agents that can be stored for long durations and are effective against hydrogen sulfide poisoning immediately.

A study  published online on December 10, 2024, in Scientific Reports has proposed a novel antidote for hydrogen sulfide poisoning.

Researchers decided to tackle this problem by using artificial heme-model compounds that would have a higher affinity towards hydrogen sulfide than the native hemes present in our bodies.

They  have developed and studied synthetic heme-model compounds (hemoCDs) over the last two decades.

In this study, they decided to test if  two of those complexes had the potential to "scavenge" hydrogen sulfide in an aqueous medium. Interestingly, they found that met-hemoCD-I in particular had a very high affinity for hydrogen sulfide under normal physiological conditions—almost 10 times higher than that of human met-hemoglobin.

Met-hemoCD-I was able to convert toxic hydrogen sulfide into nontoxic sulfite and sulfate ions, indicating that it could be used to treat hydrogen sulfide poisoning.

Part 1

To test this antidote, they injected hydrogen sulfide-treated mice with met-hemoCD-I. The results were very promising—mice injected with met-hemoCD-I showed improved survival rates compared to mice that were not given the antidote. Additionally, CcO activity in the brain and heart tissues (which had decreased because of poisoning) recovered and returned to normal.
Another aspect of met-hemoCD-I that makes it a very promising antidote is its demonstrated safety—it was found that injected met-hemoCD-I was excreted in the urine of the rats without undergoing any chemical decomposition in their body.

The results of this study show that hemoCD-Twins could be used as a powerful antidote to treat carbon monoxide, hydrogen cyanide, and now hydrogen sulfide poisoning without the risk of any side effects.
Using hemoCD-Twins, we can provide one powerful solution for multiple gas poisoning, even if the cause of poisoning is unknown.
Clinical trials are about to be started with this antidote.

 Nakagami, A., et al. Detoxification of hydrogen sulfide by synthetic heme model compounds, Scientific Reports (2024). DOI: 10.1038/s41598-024-80511-1

Part 2

Human disruption is driving 'winner' and 'loser' tree species shifts across Brazilian forests, study shows

An international team of researchers examined a unique dataset of more than 1,200 tropical tree species over more than 270 forest plots across six regions of Brazilian Amazon and Atlantic forests that have been altered by people through activities such as deforestation and local disturbances like logging, hunting and burning.

Fast-growing and small-seeded tree species are dominating Brazilian forests in regions with high levels of deforestation and degradation, a study shows. This has potential implications for the ecosystem services these forests provide, including the ability of these "disturbed" forests to absorb and store carbon. This is because these "winning" species grow fast but die young, as their stems and branches are far less dense than the slow growing tree species they replace.

Wildlife species adapted to consuming and dispersing the large seeds of tree species that are being lost in human-modified landscapes may also be affected by these shifts.

Authors of the study, "Winner-loser plant trait replacements in human-modified tropical forests" published in Nature Ecology & Evolution, say their findings highlight the urgent need to conserve and restore tropical forests, prevent degradation, and implement measures to protect and boost populations of the large-bodied birds like toucans and mammals such as spider monkeys that disperse the seeds of "losing" slow-growing large-seeded tree species.

The researchers looked at the overall structure of the landscapes surrounding each forest plot and, using multiple statistical models, they were able to identify the causal effects of habitat loss, fragmentation and local degradation on the composition of forests, as well as identifying the attributes of so-called "winners" and "losers" species.

They found that the tree species dominating landscapes with high forest cover tend to have dense wood and large seeds, which are primarily dispersed by medium to large-bodied animals typical of Brazil's rainforests. 

In contrast, in highly deforested landscapes, where remaining forests face additional human disturbances, these tree species are losing out to so-called 'opportunistic' species, which have softer wood and smaller seeds consumed by small, mobile, disturbance-adapted birds and bats. These species typically grow faster and have greater dispersal capacity.

The researchers found this was happening despite differing geography, climate and land-use contexts.

This study highlights the urgent need to strengthen the conservation and restoration of tropical forests to preserve these vital ecosystems.

Tropical forests constitute the most important reservoir of terrestrial biodiversity. They play a major role in absorbing greenhouse gases and provide essential ecosystem services. Yet they are victims of rapid deforestation and fragmentation, with the loss of 3 to 6 million hectares per year over the last two decades.

Winner-loser plant trait replacements in human-modified tropical forests, Nature Ecology & Evolution (2024). DOI: 10.1038/s41559-024-02592-5

Toxoplasma gondii parasite uses unconventional method to make proteins for evasion of drug treatment, research reveals

A study by  Medicine researchers sheds new light on how Toxoplasma gondii parasites make the proteins they need to enter a dormant stage that allows them to escape drug treatment. The research is published in the Journal of Biological Chemistry.

Toxoplasma gondii is a single-celled parasite that people catch from cat feces, unwashed produce or undercooked meat. The parasite has infected up to one-third of the world's population, and after causing mild illness, it persists by entering a dormant phase housed in cysts throughout the body, including the brain.

Toxoplasma cysts have been linked to behavior changes and neurological disorders like schizophrenia. They can also reactivate when the immune system is weakened, causing life-threatening organ damage.

While drugs are available to put toxoplasmosis into remission, there is no way to clear the infection. A better understanding of how the parasite develops into cysts would help scientists find a cure.

 Researchers have shown that Toxoplasma forms cysts by altering which proteins are made. Proteins govern the fate of cells and are encoded by mRNAs.

But mRNAs can be present in cells without being made into protein. Researchers have  shown that Toxoplasma switches which mRNAs are made into protein when converting into cysts.

Researchers examined the so-called leader sequences of genes named BFD1 and BFD2, both of which are necessary for Toxoplasma to form cysts.

mRNAs not only encode for protein, but they begin with a leader sequence that contains information on when that mRNA should be made into protein.

All mRNAs have a structure called a cap at the beginning of their leader sequence. Ribosomes, which convert mRNA into protein, bind to the cap and scan the leader until it finds the right code to begin making the protein.

What the researchers now found is during cyst formation, BFD2 is made into protein after ribosomes bind the cap and scan the leader, as expected. 

But BFD1 does not follow that convention. Its production does not rely on the mRNA cap like most other mRNAs."

The team further showed that BFD1 is made into protein only after BFD2 binds specific sites in the BFD1 mRNA leader sequence. This is a phenomenon called cap-independent translation, which is more commonly seen in viruses.

Finding it in a microbe that has cellular anatomy like our own was surprising.

Vishakha Dey et al, Cap-independent translation directs stress-induced differentiation of the protozoan parasite Toxoplasma gondii, Journal of Biological Chemistry (2024). DOI: 10.1016/j.jbc.2024.107979

Brain mechanisms underpinning loss of consciousness identified

The shift from an awake state to unconsciousness is a phenomenon that has long captured the interest of scientists and philosophers alike, but how it happens has remained a mystery—until now. Through studies on rats, a team of researchers at Penn State has pinpointed the exact moment of loss of consciousness due to anesthesia, mapping what happens in different brain regions during that moment.

The study has implications for humans as well as for other types of loss of consciousness, such as sleep, the researchers said. They published their results in Advanced Science.

In this study the researchers combined two different methods: electrophysiology studies and functional magnetic resonance imaging (fMRI). By measuring electrophysiological signals—or electrical activity—in the brain very quickly over time, the researchers determined the precise moment that the rat transitioned from an awake state to an unconscious one.  

They next overlaid this time-stamped data with the fMRI map of activity in the whole brain to investigate different regions of the brain during that transition.

They  found that there were three regions in the brain that showed transient changes in their activities during the moment of lost consciousness: the medial prefrontal cortex, the hippocampus and the thalamus.

While these regions have been implicated in unconscious states in the existing scientific literature, this new research was the first to indicate how these regions might interact with each other and what kind of role they might play during the moment of loss of consciousness.

The researchers said previous work also did not indicate whether the activity in those three regions was a cause or an effect of loss of consciousness.

The results suggest that loss of consciousness may be triggered by sequential events in these three regions, while activity increases in other cortical regions may be a consequence, rather than a cause, of loss of consciousness.

The results do provide new insights into the roles of these brain regions in loss of consciousness.

Xiaoai Chen et al, Sequential Deactivation Across the Hippocampus‐Thalamus‐mPFC Pathway During Loss of Consciousness, Advanced Science (2024). DOI: 10.1002/advs.202406320