Scientists discover laser light can cast a shadow

Can light itself cast a shadow? Researchers have found that under certain conditions, a laser beam can act like an opaque object and cast a shadow. The discovery challenges the traditional understanding of shadows and opens new possibilities for technologies that could use a laser beam to control another laser beam.

Laser light casting a shadow was previously thought impossible since light usually passes through other light without interacting. This new demonstration of a very counter-intuitive optical effect invites us to reconsider our notion of shadow.

In Optica, researchers describe how they used a ruby crystal and specific laser wavelengths to show that a laser beam could block light and create a visible shadow due to a nonlinear optical process. This effect occurs when light interacts with a material in an intensity-dependent way and can influence another optical field.

The new research is part of a larger exploration into how a light beam interacts with another light beam under special conditions and nonlinear optical processes.

 The researchers directed a high-power green laser through a cube made of standard ruby crystal and illuminated it with a blue laser from the side. When the green laser enters the ruby, it locally changes the material response to the blue wavelength. The green laser acts like an ordinary object while the blue laser acts like illumination.

The interaction between the two light sources created a shadow on a screen that was visible as a dark area where the green laser blocked the blue light. It met all the criteria for a shadow because it was visible to the naked eye, followed the contours of the surface it fell on and followed the position and shape of the laser beam, which acted as an object.

The laser shadow effect is a consequence of optical nonlinear absorption in the ruby. The effect occurs because the green laser increases the optical absorption of the blue illuminating laser beam, creating a matching region in the illuminating light with lower optical intensity. The result is a darker area that appears as a shadow of the green laser beam.

This discovery expands our understanding of light-matter interactions and opens up new possibilities for utilizing light in ways we hadn't considered before.

The researchers experimentally measured the dependence of the shadow's contrast on the laser beam's power, finding a maximum contrast of approximately 22%, similar to the contrast of a tree's shadow on a sunny day. They also developed a theoretical model and showed that it could accurately predict the shadow contrast.

 Raphael Abrahao et al, The shadow of a laser beam, Optica (2024). DOI: 10.1364/OPTICA.534596

Altering two genes to produce sweeter tomatoes without sacrificing size, weight or yield

A team of horticulturists, bio-breeders and agriculture specialists affiliated with a host of institutions across China has produced sweeter tomatoes without sacrificing size, weight or yield by altering two of their genes. In their study, published in the journal Nature, the group modified the genes of a tomato variant that coded for proteins that lowered levels of enzymes related to sugar production.

Over the past several centuries, farmers around the world have crossbred tomato plants with the aim of improving yields and increasing fruit size. The result has been a massive growth in both. Unfortunately, making tomatoes bigger has also made them less sweet. Past efforts to make large modern tomatoes sweeter have resulted in smaller yields.
For this new study, the research team took a new approach. They began by looking into the reason for the loss of sweetness in tomatoes and partially corrected crossbreeding effects on the tomato genome.

The research team discovered two genes in multiple tomato variants that were more active in larger varieties. Called SlCDPK26 and SlCDPK27, the two genes were found to code for proteins that lowered the levels of enzymes that produce sugar. The researchers next genetically modified the genome of a variety of large tomato called Money Maker to disable the two genes they had identified.

Plants grown with the modification produced tomatoes with a 30% increase in fructose and glucose levels with no reduction in size or weight. The team further confirmed that the tomatoes were sweeter by tasting them. The gene alterations did not diminish yields—the only other difference they found was that the tomatoes produced fewer seeds, which were also smaller. They suggest consumers would probably like this added feature.

Jinzhe Zhang et al, Releasing a sugar brake generates sweeter tomato without yield penalty, Nature (2024). DOI: 10.1038/s41586-024-08186-2

Amy Lanctot et al, Tomato engineering hits the sweet spot to make big sugar-rich fruit, Nature (2024). DOI: 10.1038/d41586-024-03302-8

Maternal stress linked to increased early onset epilepsy in children

 Researchers in Japan have linked maternal psychological distress during pregnancy to an increased risk of epilepsy in children.

Epilepsy affects 65 million people globally and is one of the most prevalent neurological disorders. Individuals with epilepsy often face discrimination and social stigma, enduring stress from living with a chronic, unpredictable disease.
Early onset of epilepsy before the age of three is associated with high rates of drug resistance and developmental delays. Previous studies have identified potential factors like placental abruption, eclampsia, infection during pregnancy, low birth weight, and artificial milk as risk factors for early childhood epilepsy.

In a research article, "The impact of maternal prenatal psychological distress on the development of epilepsy in offspring: The Japan Environment and Children's Study," published in PLOS ONE, researchers used a dataset obtained from the Japan Environment and Children's Study, a nationwide birth cohort involving nearly 100,000 participants, to evaluate the association between six-item Kessler Psychological Distress Scale (K6) scores of mothers and epilepsy among 1 to 3-year-olds.

Self-reported data on 97,484 children were retrospectively analyzed for connections between the stress scores of expecting mothers and epilepsy outcomes in their children.

Maternal psychological distress was assessed using the six-item Kessler Psychological Distress Scale (K6), administered twice during pregnancy: once in the first half (median 15.1 weeks) and again in the second half (median 27.4 weeks). Participants were categorized into six groups based on K6 scores, classified as either low (4 or less) or moderate (5 or 6) distress at each time point.
Children diagnosed with epilepsy at ages 1, 2, and 3 numbered 89 (0.1%), 129 (0.2%), and 149 (0.2%), respectively. Findings indicated that a maternal K6 score of 5 or higher at both time points was associated with 70% higher epilepsy diagnosis ratios among children aged 1 to 3 years. Multivariate analysis confirmed this association, even after adjusting for potential confounding factors like low birth weight and chromosomal abnormalities.

The study concludes that "...environmental adjustments to promote relaxation in pregnant women are needed," which makes a tremendous amount of good sense, though they continue "...to prevent the development of epilepsy in their offspring," which might be a little more than what the study is actually telling us.

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The 70% increase is significant, though even with high maternal stress, epilepsy remains an extremely rare condition, and other factors seemed more prominent in the study analyses. Low birth weight was associated with a 180% increased risk by age 1, introduction to artificial milk in the first month showed a 203% increased risk by age 2, and having any chromosome abnormalities increased the risk by 2100% at age 1, 1567% at age 2, and 1000% at age 3.

 Yuto Arai et al, The impact of maternal prenatal psychological distress on the development of epilepsy in offspring: The Japan Environment and Children's Study, PLOS ONE (2024). DOI: 10.1371/journal.pone.0311666

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Detecting cancer in urine: Nanowire-based capture of micro-ribonucleic acids

Cancer has a high death rate with delayed diagnosis of the disease being one of the main reasons for its fatality. Early diagnosis of cancer is vital to improving patient outcomes and in recent years, the development of diagnostic tools to detect early-stage cancer has gained a lot of attention.

Cancer cells utilize specific micro-ribonucleic acids (miRNAs)-small noncoding RNAs to regulate gene expression and promote tumor formation. While circulating miRNAs are viable biomarkers of early cancer disease, the identification of cancer-related miRNAs in blood and other body fluids remains a challenge.

In this light, a team of researchers have focused their efforts on nanowire-based miRNA extraction and machine learning (ML) analysis to detect cancer-associated miRNAs in urine. Their research findings were published online in the journal Analytical Chemistry on October 18, 2024.

Circulating miRNAs in the blood are mostly encapsulated in extracellular vesicles (EVs) and carry critical regulatory information. These miRNAs differ between healthy individuals and those with cancer. By utilizing zinc oxide (ZnO) nanowires to capture and extract miRNAs in urine, the research group has attempted to develop a non-invasive cancer detection tool.

Initially, the scientists utilized ZnO nanowires to capture EVs in urine samples and incorporated microarray technology to identify specific gene sequences in EV-encapsulated miRNAs. The ultracentrifugation technique was further used to compare and validate the efficiency of miRNA capture by nanowires.

The results revealed that EVs containing miRNAs, including exosomes-unique subtypes of EVs with sizes ranging from 40 nm to 200 nm, were efficiently captured on nanowires. Moreover, the presence of 2,486 miRNA species was confirmed during the miRNA profiling analysis of 200 urine samples.

Driven by the discovery of more than 2,000 miRNA species in urine samples, Yasui and the team hypothesized that most of the miRNAs in blood could be transferred to urine during the filtration process in kidneys. Subsequently, they employed a logistic regression classifier constructed using ML to identify lung cancer-associated urinary miRNA ensembles. The findings revealed one particular urinary miRNA ensemble, composed of 53 miRNA species, that could differentiate cancer and noncancer subjects with very high specificity and sensitivity.

Takao Yasui et al, Early Cancer Detection via Multi-microRNA Profiling of Urinary Exosomes Captured by Nanowires, Analytical Chemistry (2024). DOI: 10.1021/acs.analchem.4c02488

Scientists find a new way of entangling light and sound

For a wide variety of emerging quantum technologies, such as secure quantum communications and quantum computing, quantum entanglement is a prerequisite. Scientists at the Max-Planck-Institute for the Science of Light (MPL) have now demonstrated a particularly efficient way in which photons can be entangled with acoustic phonons.

The researchers were able to demonstrate that this entanglement is resilient to external noise, the usual pitfall of any quantum technology to date. They published their research in Physical Review Letters.

Changlong Zhu et al, Optoacoustic Entanglement in a Continuous Brillouin-Active Solid State System, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.203602

Quantum entanglement is a phenomenon in which particles become interconnected such that the state of one instantly influences the state of the other, regardless of the distance between them. Entanglement is an important phenomenon for many quantum technology applications because it can lead to secure quantum communications and high-dimensional quantum computing.

As photons, quanta of light, can propagate extremely fast while carrying quantum information, the entangling of pairs of photons via nonlinear optics is an established procedure.

Scientists at MPL have recently tackled the issue of establishing entanglement between very different entities, such as traveling sound waves, phonons, and optical photons. The proposed optoacoustic entanglement scheme is based on Brillouin scattering. It is particularly resilient, suitable for integration into quantum signal processing schemes and implementable at high environmental temperatures.
Entanglement has historically been fascinating at many different levels, as it strongly connects to our understanding of the fundamental laws of nature.

Quantum correlations among particles can persist even when separated by large distances. At the practical level, quantum entanglement is at the heart of many emerging quantum technologies. In the optical domain, entanglement of photons is fundamental to secure quantum communication methods or quantum computing schemes.
Photons, however, are volatile. Therefore, feasible alternatives are being sought for certain applications, such as quantum memory or quantum repeater schemes. One such alternative is the acoustic domain, where quanta are stored in acoustic or sound waves.

Scientists at the MPL have now indicated a particularly efficient way in which photons can be entangled with acoustic phonons: While the two quanta travel along the same photonic structures, the phonons move at a much slower speed. The underlying effect is the optical nonlinear effect known as Brillouin-Mandelstam scattering. It is responsible for coupling quanta at fundamentally different energy scales.

In their study, the scientists showed that the proposed entangling scheme can operate at temperatures in the tens of Kelvin. This is much higher than those required by standard approaches, which often employ expensive equipment such as dilution fridges. The possibility of implementing this concept in optical fibers or photonic integrated chips makes this mechanism of particular interest for use in modern quantum technologies.
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Spectacular chimneys discovered in the Dead Sea

Researchers have discovered meter-high chimneys on the floor of the Dead Sea. These are formed by the spontaneous crystallization of minerals from groundwater with an extremely high salt content flowing up out of the lake floor, they report in the journal Science of the Total Environment.

Discovered for the first time, these vents are an important early warning indicator for sinkholes. These subsidence craters form in the area surrounding the Dead Sea and pose a significant hazard to the population.

While black smokers along the mid-ocean ridge emit hot water containing sulfides at a depth of several thousand meters, the researchers in the Dead Sea discovered that highly saline groundwater flows out through the chimneys at the bottom of the lake.

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But where is the salt coming from? The explanation: The groundwater from the surrounding aquifers penetrates into the saline lake sediments, leaching out extremely old and thick layers of rock consisting mainly of the mineral halite. It then flows into the lake as brine.

Because the density of this brine is somewhat lower than that of the water in the Dead Sea, it rises upwards like a jet. It looks like smoke, but it's a saline fluid.
Contact with the lake water causes the dissolved salts, especially the halite, to spontaneously crystallize after emerging from the lake bed, where it forms the vents observed for the first time in the world. These can grow by several centimeters within a single day. Many of the slender chimneys were one to two meters high, but they also include giants more than seven meters high, with a diameter of more than 2–3 meters.
These white smokers are especially important because they can serve as an early warning indicator for sinkholes. These are subsidence craters up to 100 meters wide and up to 20 meters deep, thousands of which have formed along the Dead Sea in recent decades.

C. Siebert et al, A new type of submarine chimneys built of halite, Science of The Total Environment (2024). DOI: 10.1016/j.scitotenv.2024.176752

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Electric field signals reveal early warnings for extreme weather, study reveals

A new study  has made significant advances in understanding how atmospheric electric field measurements can help predict severe weather events.

The research paper, titled "Understanding heavy precipitation events in southern Israel through atmospheric electric field observations," is now published in Atmospheric Research.

By closely examining low-pressure winter weather systems, known as "Cyprus Lows," in the arid Negev Desert of southern Israel, this research reveals new insights into the role of the electric field in anticipating heavy precipitation.

Focusing on "wet" Cyprus Lows—situations where rain falls as a cold front moves through—researchers observed substantial increases in the potential gradient of the electric field. Minute-by-minute data showed potential gradient values rising sharply from typical fair-weather levels (about 100–200 volts per meter) to hundreds and even thousands of volts per meter during rainfall.

These surges occurred as convective clouds passed overhead, indicating that different cloud types produce unique electric field patterns. The study also highlighted that factors beyond rain intensity, such as cloud structure and the electrical charge of rain droplets, play roles in these electric fluctuations.

Through these findings, the researchers identified how electric field variations correlate with specific weather conditions. This enhanced understanding of electric field responses to weather events could significantly improve nowcasting systems for predicting extreme weather, particularly in regions prone to flash floods and sudden weather changes.

This research demonstrates how electric field variations can serve as indicators of shifting weather patterns, allowing us to anticipate severe weather events in real-time.

Roy Yaniv et al, Understanding heavy precipitation events in southern Israel through atmospheric electric field observations, Atmospheric Research (2024). DOI: 10.1016/j.atmosres.2024.107757

Living microbes discovered in Earth's driest desert 

The Atacama Desert, which runs along the Pacific Coast in Chile, is the driest place on the planet and, largely because of that aridity, hostile to most living things. Not everything, though—studies of the sandy soil have turned up diverse microbial communities. Studying the function of microorganisms in such habitats is challenging, however, because it's difficult to separate genetic material from the living part of the community from genetic material of the dead.

A new separation technique can help researchers focus on the living part of the community. This week in Applied and Environmental Microbiology, an international team of researchers describes a new way to separate extracellular (eDNA) from intracellular (iDNA) genetic material. The method provides better insights into microbial life in low-biomass environments, which was previously not possible with conventional DNA extraction methods.

The microbiologists used the novel approach on Atacama soil samples collected from the desert along a west-to-east swath from the ocean's edge to the foothills of the Andes mountains. Their analyses revealed a variety of living and possibly active microbes in the most arid areas.

Alexander Bartholomäus et al. Inside the Atacama Desert: uncovering the living microbiome of an extreme environment, Applied and Environmental Microbiology (2024). DOI: 10.1128/aem.01443-24 journals.asm.org/doi/10.1128/aem.01443-24

How does the brain keep calm? Insight into brain stability and the key role of NMDA receptors

Researchers  have made a fundamental discovery: the NMDA receptor (NMDAR)—long studied primarily for its role in learning and memory—also plays a crucial role in stabilizing brain activity.

By setting the "baseline" level for activity in neural networks, the NMDAR helps maintain stable brain function amidst continuous environmental and physiological changes. This discovery may lead to innovative treatments for diseases linked to disrupted neural stability, such as depression, Alzheimer's disease, and epilepsy.

In recent decades, brain research has mainly focused on processes that allow information encoding, memory, and learning, based on changes in synaptic connections between nerve cells. But the brain's fundamental stability, or homeostasis, is essential to support these processes.

This comprehensive project used three primary research methods: electrophysiological recordings from neurons in both cultured cells (in vitro) and living, behaving mice (in vivo) within the hippocampus, combined with computational modeling (in silico). Each approach provided unique insights into how NMDARs contribute to stability in neural networks.

These  findings suggest that ketamine's actions may stem from this newly discovered role of NMDAR: reducing the activity baseline in overactive brain regions seen in depression, like the lateral habenula, without interfering with homeostatic processes. This discovery could reshape our understanding of depression and pave the way for developing innovative treatments.

Antonella Ruggiero et al, NMDA receptors regulate the firing rate set point of hippocampal circuits without altering single-cell dynamics, Neuron (2024). DOI: 10.1016/j.neuron.2024.10.014

Cholesterol may not be the only lipid involved in trans fat-driven cardiovascular disease
Excess cholesterol is known to form artery-clogging plaques that can lead to stroke, arterial disease, heart attack, and more, making it the focus of many heart health campaigns. Fortunately, this attention to cholesterol has prompted the development of cholesterol-lowering drugs called statins and lifestyle interventions like dietary and exercise regimens. But what if there's more to the picture than just cholesterol?
New research from Salk Institute scientists describes how another class of lipids, called sphingolipids, contributes to arterial plaques and atherosclerotic cardiovascular disease (ASCVD). Using a longitudinal study of mice fed high-fat diets—with no additional cholesterol—the team tracked how these fats flow through the body and found the progression of ASCVD induced by high trans fats was fueled by the incorporation of trans fats into ceramides and other sphingolipids. Knowing that sphingolipids promote atherosclerotic plaque formation reveals another side of cardiovascular disease in addition to cholesterol.

The findings, published in Cell Metabolism, open an entirely new avenue of potential drug targets to address these diseases and adverse health events like stroke or heart attacks.

When dietary fats enter the body through the foods we eat, they must be sorted and processed into compounds called lipids, such as triglycerides, phospholipids, cholesterol, or sphingolipids. Lipoproteins—like the familiar HDL, LDL, and VLDL—are used to transport these lipids through the blood.

Sphingolipids have become useful biomarkers for diseases like ASCVD, non-alcoholic fatty liver disease, obesity, diabetes, peripheral neuropathy, and neurodegeneration. However, it is unclear exactly how the incorporation of different dietary fats into sphingolipids leads to the development of ASCVD.

The fate of dietary fat is often determined by the protein that metabolizes it. 

The team suspected that trans fats were being incorporated into sphingolipids by SPT, which, in turn, would promote the excess lipoprotein secretion into the bloodstream that causes ASCVD.

To test their theory, they compared the processing of two different fats, cis fats and trans fats. The difference between these two comes down to the placement of a hydrogen atom; cis fats, found in natural foods like fish or walnuts, have a kink in their structure caused by two side-by-side hydrogen atoms, whereas trans fats, found in processed foods like margarine or anything fried, have a straight-chain structure caused by two opposing hydrogen atoms. Importantly, the kink in cis fats means they cannot be tightly packed—a positive feature for avoiding impenetrable clogs.

The researchers combined mouse model dietary manipulation with metabolic tracing, pharmacological interventions, and physiological analyses to answer their question—what is the link between trans fats, sphingolipids, and ASCVD?

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The researchers found the incorporation of trans fats through SPT increased lipoprotein secretion from the liver, which then promoted the formation of atherosclerotic plaques.
In the end, they saw mice consuming a high trans fat diet were producing trans fat-derived sphingolipids that promoted the secretion of VLDL from the liver into the bloodstream. This, in turn, accelerated the buildup of atherosclerotic plaques and the development of fatty livers and insulin dysregulation. High cis-fat diet mice, on the other hand, experienced shorter-term, less harmful effects like weight gain.

Jivani M. Gengatharan et al, Altered sphingolipid biosynthetic flux and lipoprotein trafficking contribute to trans-fat-induced atherosclerosis, Cell Metabolism (2024). DOI: 10.1016/j.cmet.2024.10.016

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Scientists Put Cats in Microgravity to See What Would Happen

There is, perhaps, no animal on this planet as lithe as the simple domestic cat. And not least in their bag of acrobatic tricks is one for which they are well-known: the ability to land, safely, on their velvet paws, when subjected to a tumble.

In the 1950s, humans discovered parabolic flight: the ability to simulate zero-G conditions using specially-designed aircraft plummeting along a precise flight trajectory. And with that came a devilish thought. What would happen to a cat's ability to land on its feet if they can't tell the difference between up and down?
So, this is what the bright minds at the US Air Force Aerospace Medical Research Lab decided to find out.

Parabolic flight is not true microgravity, but a brief experience of its effect. Just as a rapid descent in an elevator can make you feel lighter in your loafers, passengers on an aircraft will experience weightlessness while rapidly descending from a high altitude to a lower one. It's pretty disorienting, earning parabolic flight the nickname 'vomit comet' for good reason.

https://spacemedicineassociation.org/download/history/history_files...

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The first experiments were conducted on board a Convair C-131 Samaritan, and yes, there is absolutely video of the proceedings. A similar experiment involved releasing pigeons inside the C-131 during parabolic flight.

It's fascinating to watch. The narration for the video says the cats' "automatic reflex action is almost completely lost under weightlessness". Almost – but not quite. Although the cats seem disoriented, they are still able to twist and turn their bodies around as they try to figure out where they are going to fall.
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Blood vessel-like coating could make medical devices safer for patients

Researchers have developed a coating that could make medical devices safer for millions of patients, reducing the risks associated with blood clots and dangerous bleeding. The work has been published in Nature Materials.

The new material, designed to mimic the natural behavior of blood vessels, could allow for safer use of blood-contacting devices like catheters, stents, blood-oxygenation machines and dialysis machines—especially in cases where blood clots are a significant concern.

This discovery could be a transformative step in the development of safer medical devices. By designing a coating that mimics the body's natural approach to preventing clots, researchers have created a solution that could dramatically reduce the need for risky blood thinners before and after patients use these devices.

Thrombosis, or clot formation, is a major challenge when blood-contacting devices are used. Unlike natural blood vessels, these devices can trigger clotting by activating specific proteins in the blood. Blood clots can obstruct the device, disrupting treatment, or lead to severe complications such as stroke and heart attack.

Doctors often prescribe high doses of blood thinners to prevent clots on these devices, but this approach increases the risk of dangerous bleeding—a trade-off that many patients and clinicians would rather avoid.

The newly developed coating offers a promising alternative. It's engineered to imitate how blood vessels function—encouraging normal blood flow without triggering clot formation. Imagine the coating as a "soft barrier" on a device that attracts a key blood protein but keeps it from activating the clotting process.

By interacting with this protein in a controlled way, the coating prevents it from sparking a cascade of events that lead to clot formation.

In lab and animal studies, the coating demonstrated significant reductions in clot formation on device surfaces, without the use of blood thinners and without affecting the normal clotting functions elsewhere in the body.

One of the most surprising insights was that controlling the interaction between the coating and specific blood proteins could prevent clotting without disrupting the body's natural balance. This shows us that mimicking the body's own mechanisms, rather than simply repelling blood components, is key to truly biocompatible device design.

The innovation comes as demand for blood-contacting devices continues to rise. 

Additionally, the team is interested in understanding whether this approach could eventually be adapted to address other blood-related complications, such as inflammation or infection, in long-term medical implants.

Antithrombotic coating with sheltered positive charges prevents contact activation by controlling factor XII–biointerface binding, Nature Materials (2024). DOI: 10.1038/s41563-024-02046-0

'Moonlighting' enzymes may lead to new cancer therapies

Researchers at the Center for Genomic Regulation (CRG) reveal that metabolic enzymes known for their roles in energy production and nucleotide synthesis are taking on unexpected "second jobs" within the nucleus, orchestrating critical functions like cell division and DNA repair.

The discovery, reported in two separate research papers in Nature Communications, not only challenges longstanding biological paradigms in cellular biology but also opens new avenues for cancer therapies, particularly against aggressive tumors like triple-negative breast cancer (TNBC).

For decades, biology textbooks have neatly compartmentalized cellular functions. Mitochondria are the powerhouses of the cell, the cytoplasm is a bustling factory floor for protein synthesis, and the nucleus a custodian of genetic information. However, scientists have now discovered that the boundaries between these cellular compartments are less defined than previously thought.

Metabolic enzymes are moonlighting outside of their traditional neighborhood. There's an overlap in the skillset, but they're doing entirely different jobs for entirely different purposes. Surprisingly, their secondary roles in the nucleus are just as critical as their primary metabolic functions.

In one of the studies, researchers  focused on the metabolic enzyme MTHFD2. Traditionally, MTHFD2 is found in the mitochondria, where it plays a key role in synthesizing the building blocks of life and contributing to cell growth. Others research  work reveals that MTHFD2 also moonlights within the nucleus, where it plays a pivotal role in ensuring proper cell division.

The study is the first to demonstrate that the nucleus relies on metabolic pathways to maintain the integrity and stability of the human genome. The nucleus isn't just a passive storage space for DNA; it has its own metabolic needs and processes.

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In the second study, researchers turned their attention to triple-negative breast cancer, the most aggressive type of breast cancer there is. The disease is responsible for around one in eight breast cancer diagnoses and amounts to roughly 200,000 new cases each year worldwide.

Usually, excessive DNA damage triggers cell death. However, TNBC has a propensity to accumulate DNA damage without consequence, making it resilient to conventional treatments. The study helps partly explain why: the metabolic enzyme IMPDH2 relocates to the nucleus of TNBC cells to assist in DNA repair processes.

IMPDH2 acts like a mechanic in the cell's nucleus, controlling the DNA damage response that would otherwise kill the cancer cell.
By experimentally manipulating IMPDH2 levels, the team found they could tip the balance. Increasing IMPDH2 within the nucleus overwhelmed the cancer cells' repair machinery, causing cells to self-destruct.

It's like overloading a sinking ship with more water—eventually, it sinks faster. Their approach effectively forces TNBC cells to succumb to the very DNA damage they are typically resilient to.
The study can also lead to new ways of monitoring cancer. The research on IMPDH2 also studied its interaction with PARP1, a protein already targeted by existing cancer drugs. IMPDH2 could serve as a biomarker to predict which tumors will respond to PARP1 inhibitors.
Both studies contribute to an emerging field of therapies targeting cancer by exploiting its metabolic vulnerabilities.

Nuclear localization of MTHFD2 is required for correct mitosis progression, Nature Communications (2024). DOI: 10.1038/s41467-024-51847-z

Nuclear IMPDH2 controls the DNA damage response by modulating PARP1 activity, Nature Communications (2024). DOI: 10.1038/s41467-024-53877-z

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DNA packaging directly affects how fast DNA is copied in cells, scientists discover

Researchers have found that the way DNA is packaged in cells can directly impact how fast DNA itself is copied during cell division. They discovered that DNA packaging sends signals through an unusual pathway, affecting the cell's ability to divide and grow.

This opens up new doors to study how the copying of the DNA and its packaging are linked. These findings, published in Molecular Cell, may help scientists to find therapies and medicines for diseases such as cancer in the future.

Every day, our cells divide. Each time they need to copy both their DNA and the structure in which the DNA is packed. This packaging, called chromatin, acts as a guide. It tells the cell how, where and when to 'read' and use the information in the DNA. It is important that both the DNA and its chromatin are copied accurately to ensure young and healthy cells. Problems with this process are often seen in diseases like cancer.

The copying of chromatin has a direct effect on the mechanisms that copy DNA itself. If there is a problem with DNA packaging, the cell quickly senses this issue. But instead of triggering a typical stress response, the cell responds by slowing down its cycle of growth and division, without stopping it completely. The slower cycle still allows the cell to divide, but the new cells often struggle to continue to grow, preventing them from dividing again.

So, these mechanisms, which copy DNA and its packaging, are closely connected to cell growth. This discovery paves the way for new studies on these pathways and how DNA packaging can control cell growth. In the future, this knowledge could help to find new treatments for diseases like cancer.

 Acute multi-level response to defective de novo chromatin assembly in S-phase, Molecular Cell (2024). DOI: 10.1016/j.molcel.2024.10.023. www.cell.com/molecular-cell/fu … 1097-2765(24)00863-3

'Drowning' and 'dying' mangrove forests in Maldives signal global coastal threat, say researchers

Researchers have found evidence that mangrove forests—which protect tropical and subtropical coastlines—are drowning in the Maldives.

Their findings, published 12 November in Scientific Reports,

The research team, led by Northumbria University, warn that the findings have implications not only for the Maldives, but also for other island nations and coastal ecosystems around the world.

In 2020, more than a quarter of the Maldivian islands containing mangrove forests saw their trees experiencing a gradual deterioration before dying, a condition known as dieback.

In 2020, more than a quarter of the Maldivian islands containing mangrove forests saw their trees experiencing a gradual deterioration before dying, a condition known as dieback.
Satellite imagery of both inhabited and uninhabited islands revealed the severity of this issue, showing that some islands lost over half of their mangrove cover.

Mangroves play an essential role in protecting coastal regions by acting as natural barriers against storms, erosion and flooding. As biodiversity hotspots, they are vital nurseries for marine species such as crabs, prawns and fish making them crucial for food security and livelihoods in many coastal communities. They also provide valuable resources such as construction materials for housing.

Researchers combined evidence from sea level, climate data and remote sensing with field observations of sediment geochemistry and dendrology to investigate the mangrove dieback.

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Their analysis of mangrove wood revealed that the dead trees showed greater signs of salinity stress compared to living trees.

This stress indicates that the roots of the trees were struggling to cope with increased salt levels, which was a key factor in their eventual death.
The researchers found that sea levels around the Maldives rose at an accelerated rate of over 30mm per year between 2017 to 2020. Towards the end of this period, an unusually intense climate phenomenon known as the Indian Ocean Dipole occurred. This caused warmer sea surface temperatures and an increase in sea level in the Western Indian Ocean.

Although mangroves naturally build up their own sediment, allowing them to adapt to gradually rising seas, this rate of sea level rise was too fast for the mangroves to keep pace.

As tidal movements are more limited in the basin areas where many mangrove forests grow, the rising sea level meant that seawater effectively flooded the forests. This lack of tidal movement and flooding prevented the mangroves from building the sediment they needed to stay above water. They eventually lost their resilience and died off by drowning.
As the mangroves' build-up of sediment slowed down due to the pace of the rising sea level, the soil salinity increased beyond what even these salt-tolerant trees could handle. Essentially, the mangroves were drowning.

The extreme magnitude of dieback seen in the Maldives is a vivid illustration of how climate change may push natural systems past their limits, with cascading consequences for both nature and people.

Carruthers, L. et al. Sea-level rise and extreme Indian Ocean Dipole explain mangrove dieback in the Maldives, Scientific Reports (2024). DOI: 10.1038/s41598-024-73776-z

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Plastic that dissolves in water

At a time when synthetic plastic has polluted nearly every corner of the globe and appeared in food and in the human body,  researchers have developed a new plastic that dissolves in water.

The kind of impact that human-made materials are making on the living world is resulting in climate change, pollution and more. One of the ways that we are able to address this is to make materials sustainable and also make materials which are smart or intelligent.

This new bioplastic MECHS—an acronym for Mechanical Engineered Living Materials with Compostability, Healability and Scalability is one such effort.

The researchers presented their discovery in a paper published in the journal Nature Communications.

The study showcases the researchers' most recent work with engineered living materials, which use living cells to produce functional materials.

First, the nature-inspired solutions can be made to regenerate, regulate and/or respond to external stimuli such as light and can even heal itself.

Secondly, unlike the plastics that are polluting the planet and our bodies, the materials are biodegradable in water and even the compost bin.

But while engineered living materials have been manipulated to adhere, catalyze and remediate, and be either soft or stiff, such materials have not been scalable for widespread production.

That's where MECHS comes in.

MECHS consists of engineered E. coli bacteria with a fiber matrix to create a paper- or film-like material.

The fibers give MECHS several desirable properties. It means that MECHS can stretch like plastic wrap, can be genetically engineered by adding proteins or peptides to make it more or less stiff. And it is healable—a small amount of water disentangles the fibers, which then re-entangle as the MECHS dries.

Meanwhile, a lot of water or a trip to a compost bin causes the material to dissolve. In fact, it dissolves much faster than other biodegradable plastics, the researchers found.

Finally, the material can also be easily mass produced in a process similar to paper manufacturing.

 Avinash Manjula-Basavanna et al, Mechanically Tunable, Compostable, Healable and Scalable Engineered Living Materials, Nature Communications (2024). DOI: 10.1038/s41467-024-53052-4

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Young coral use metabolic tricks to resist bleaching, research reveals

Coral larvae reduce their metabolism and increase nitrogen uptake to resist bleaching at high temperatures, according to a study published November 12 in the open-access journal PLOS Biology.

High ocean temperatures cause coral bleaching, which results from the disruption of the relationship between corals and their symbiotic algae, an increasing concern as global temperatures rise. However, relatively little research has examined the effects of high temperatures during the early life stages of corals.

In this study, researchers exposed coral larvae to high temperatures at the Hawai'i Institute of Marine Biology. For three days during their first week of development, the larvae and their algal symbionts were treated to temperatures 2.5 degrees Celsius above ambient temperature, similar to expected changes in seawater due to climate change.

The coral larvae showed no signs of bleaching in the heated water, and they were able to maintain rates of algal photosynthesis and the supply of carbon-based nutrition from the algae to the host. However, there was a 19% reduction in coral metabolism, as well as increased uptake and storage of nitrogen by the coral, both of which are apparent strategies that improve coral survival.

Reduced metabolism allows the coral to conserve energy and resources, also seen in adult corals during bleaching. The change in nitrogen cycling seems to be an adaptation by the coral to limit the amount of nitrogen available to the algae, thus preventing algal overgrowth and the destabilization of the coral-algae relationship.
It remains unclear how effective these strategies are at higher temperatures and for longer durations. Further research into the details and limitations of coral reaction to high temperatures will provide crucial knowledge for predicting coral response and protecting coral reefs as global temperatures continue to rise.

The authors add, "This research reveals that coral larvae must invest in their nutritional partnership with algae to withstand stress, offering key insights into strategies to avoid bleaching in earliest life stages of corals."

Huffmyer AS, et al. Coral larvae increase nitrogen assimilation to stabilize algal symbiosis and combat bleaching under increased temperature, PLOS Biology (2024). DOI: 10.1371/journal.pbio.3002875

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Study challenges popular belief that children are quicker at picking up new motor skills than adults

Contrary to popular belief, children aren't better at learning new skills than adults. Indeed, young adults seem to learn faster than kids—but also tend to forget more quickly. Here, better sleep seems to advantage children. This is the conclusion of a new study.

It's widely believed that children learn new motor skills faster than adults, whether it's mastering slopes or skateparks, learning new languages, doing cartwheels or picking up new dance moves from TikTok.

"There's an assumption in popular science literature and various textbooks that children in a certain age range—from roughly the age of 8 until puberty—are better at learning new skills than adults. This is often described as a 'golden age for motor skills learning.'But there's no actual physiological basis for this so-called golden age.

The popular notion of a pre-pubescent motor learning peak prompted the researchers to investigate how age-related differences in our central nervous system affect motor skill learning. Their findings are now published in Developmental Science.

In the study, the researchers tested the motor learning abilities of 132 participants from four age groups: 8–10 years, 12–14 years, 16–18 years, and 20–30 years. In a lab setting, participants practiced moving a cursor on a computer screen with fast and precise finger movements.

Participant performance was measured immediately after being introduced to the task (as a baseline), during the training session, and again 24 hours later.
During the training session itself, both the 16- to 18-year-olds and 20- to 30-year-olds improved their skills significantly more than the 8- to 10-year-olds.

"So it appears that both teenagers and younger adults are better equipped to quickly acquire new skills compared to children, who showed smaller and slower improvements. At least when it comes to short-term learning and motor skills which this study investigated,

While the researchers cannot pinpoint the exact reasons for why the adults learn faster, they have a few theories.

"The results demonstrate that the older the participants are, the more skillful they become during the early stages of training. This suggests that they get more out of the task introduction. We suspect that cognitive development and an increased ability to process information play a role—meaning adults may have more experience receiving instructions and translating them into action.

"The difference may also be because the fully developed nervous system of an adult provides better structural conditions for learning. In other words, after many years of schooling, adults may be more experienced learners and thereby more efficient at learning new things.
The picture changes when it comes to retention.

"When the researchers looked at what happens from the end of training until the participants return the next day, the dynamic reverses. While the youngest participants actually improve overnight, adults lose some of their ability to perform. This means the youngest ones are better at consolidating and reinforcing their memory after they've practiced,
According to the researchers, this suggests that sleep benefits children's learning and memory more. But other factors could also be at play. For example, older children and adults typically sleep less and have more "competing" activities throughout the day. Memory-consolidation processes in the nervous system continue for hours after the training ends.
When a math class ends, the brain keeps working on what was taught, and in doing so, reinforces memory. Sleep is known to aid consolidation. But engaging in other activities in the hours after—especially those that involve learning—can interfere with memory processes and the consolidation of what was just learned.
While the overall learning outcome doesn't vary drastically across age groups, the study does show that the learning process differs significantly depending on age, with underlying mechanisms influenced by the maturity of one's central nervous system.

Mikkel Malling Beck et al, Distinct mechanisms for online and offline motor skill learning across human development, Developmental Science (2024). DOI: 10.1111/desc.13536

Part 2

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Using personal care products during and after pregnancy can increase exposure to toxic chemicals

For people who are pregnant or nursing, more use of personal care products is associated with higher detectable levels of synthetic chemicals known to have adverse health effects, a new study by researchers has found.

The study,   published in Environment International, found that using personal care products like nail polish, makeup and hair dye while pregnant or lactating is associated with significantly higher levels of per- and polyfluoroalkyl substances, known as PFAS, in blood plasma and breast milk.

While PFAS are ubiquitous in the environment, this study indicates that personal care products are a modifiable source of PFAS. People who are concerned about their level of exposure to these chemicals during pregnancy or while breastfeeding may benefit from cutting back on personal care products during those times.

PFAS are synthetic chemicals that have been used in consumer products and industrial settings since the 1950s due to their ability to resist oil, water and heat. The study notes that PFAS have been associated with a range of adverse health effects, including liver disease, cardiometabolic and cardiovascular issues, and various cancers.

While several studies have detected these chemicals in personal care products directly, few have evaluated whether using these products impacts internal PFAS concentrations.

This is important, she added, because exposure to PFAS during pregnancy could contribute to adverse birth outcomes such as decreased birth weight, preterm birth, some neurodevelopmental disorders and diminished vaccine response in children.

The analyzed data from the Maternal-Infant Research on Environmental Chemicals Study, which enrolled 2,001 pregnant people from 10 cities across Canada between 2008 and 2011. The researchers evaluated the contribution of the use of personal care products on PFAS concentrations in prenatal plasma (6 to 13 weeks gestation) and human milk (2 to 10 weeks postpartum). Participants reported frequency of use across eight product categories during the first and third pregnancy trimesters, one to two days postpartum, and 2 to 10 weeks postpartum.

In first-trimester pregnant people, the researchers found that higher use of nail care products, fragrances, makeup, hair dyes and hair sprays or gels was associated with higher plasma PFAS concentrations. Similar results were observed for third-trimester personal care product use and breast-milk PFAS concentrations at 2 to 10 weeks postpartum.

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For instance, participants who wore makeup daily in the first and third trimesters had 14% and 17% higher plasma and breast-milk PFAS concentrations, respectively, compared to people who did not wear makeup every day. In addition, the researchers found that people using colored-permanent dye one to two days postpartum had higher PFAS levels (16% to 18% increases compared to never using them) in human milk concentrations.

The researchers noted that the study examined only four types of PFAS among thousands that are used in industry and commerce. Thus, the study likely underestimated the extent of exposure to all PFAS from these products during pregnancy.

Amber M Hall et al, Personal care product use and per- and polyfluoroalkyl substances in pregnant and lactating people in the Maternal-Infant Research on Environmental Chemicals study, Environment International (2024). DOI: 10.1016/j.envint.2024.109094

Part 2

Self-treatment sparks ethics debate

Virologist Beata Halassy treated her own breast cancer by injecting the tumour with viruses she grew in the lab. In 2020, Halassy discovered she had a second recurrence of breast cancer at the site of a previous mastectomy. To avoid another bout of chemotherapy, she self-administered experimental oncolytic virotherapy. Halassy has now been cancer-free for four years. Her decision to treat herself, and subsequently publish a report detailing the process, has sparked discussion about the ethics of self-experimentation and the risk it might encourage others to try unproven treatments. “It took a brave editor to publish the report,” says Halassy.

Nature | 
Reference: https://www.mdpi.com/2076-393X/12/9/958

Oropouche virus transmission to unborn child confirmed

The first confirmed case of vertical transmission of Oropouche virus (OROV) has been reported by 23 researchers from eight distinct institutions in Brazil.

OROV, a zoonotic arbovirus, was first isolated from the blood of a charcoal worker with a high fever in 1955 on the Caribbean island of Trinidad. Outbreaks have typically occurred south of the Amazon, isolated within Amazonian villages.

In 2024, OROV infections were detected in previously non-endemic areas across all five Brazilian regions. These expansions into previously unaffected regions involve new virus variants emerging from genetic reassortment.

In a letter to the editor titled "A Case of Vertical Transmission of Oropouche Virus in Brazil," published October 30, 2024, in the New England Journal of Medicine, researchers report on a case from Ceará, a state historically free from OROV, finding its first infection case through active laboratory surveillance.

Subsequent investigations identified 171 cases, predominantly in the rural valleys of the Baturité Massif. Agricultural landscapes in this region favor the Culicoides paraensis midge, a small biting fly sometimes referred to as "no-see-ums" due to their tiny size. Culicoides is the primary vector for OROV transmission to humans.

A notable case involved a 40-year-old pregnant woman at 30 weeks gestation who developed fever, chills, muscle aches, and severe headache. Routine prenatal care had previously identified gestational diabetes, managed with metformin, and four routine obstetric ultrasounds.

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On July 27, medical evaluation revealed light vaginal bleeding and dark discharge, with ultrasonography indicating fetal macrosomia.

By August 5, continued symptoms and decreased fetal movements led to the confirmation of fetal demise.

Molecular diagnostics confirmed acute OROV infection, ruling out dengue, Zika, chikungunya, and Mayaro viruses. Minimal invasive tissue sampling of the stillborn infant revealed OROV RNA in multiple fetal tissues, establishing vertical transmission.

Phylogenetic analysis using maximum-likelihood inference positioned the virus within the OROVBR-2019-2024 lineage, consistent with strains from the ongoing outbreak. These findings link the stillbirth directly to the current OROV spread in Brazil, highlighting the virus's potential risks during pregnancy.

The report should sound the alarm for health care providers to consider OROV infection in pregnant women presenting with fever and related symptoms in endemic or emerging regions.

 Carlos Garcia Filho et al, A Case of Vertical Transmission of Oropouche Virus in Brazil, New England Journal of Medicine (2024). DOI: 10.1056/NEJMc2412812

Part 2

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Redefining net zero will not stop global warming, scientists say

This is really absurd. Governments and countries are trying to evade climate goals to stop global warming. 

In a study, led by the University of Oxford's Department of Physics and published 18 November in Nature, an international group of authors who developed the science behind net zero demonstrate that relying on 'natural carbon sinks' like forests and oceans to offset ongoing CO2 emissions from fossil fuel use will not actually stop global warming.

The science of net zero, developed over 15 years ago, does not include these natural carbon sinks in the definition of net human-induced CO₂ emissions.

Natural sinks play a vital role in moderating the impact of current emissions and draw down atmospheric CO2 concentrations after the date of net zero, stabilizing global temperatures. Yet governments and corporations are increasingly turning to them to offset emissions, rather than reducing fossil fuel use or developing more permanent CO2 disposal options.

Emissions accounting rules encourage this by creating an apparent equivalence between fossil fuel emissions and drawdown of CO₂ by some natural carbon sinks, meaning a country could appear to have 'achieved net zero' while still contributing to ongoing warming.

The authors call on governments and corporations to clarify how much they are counting on natural carbon sinks to meet their climate goals, as well as recognizing the need for "Geological Net Zero."

Geological Net Zero means balancing flows of carbon into and out of the solid Earth, with one ton of CO₂ committed to geological storage for every ton still generated by any continued fossil fuel use. Given the cost and challenges of permanent geological CO₂ storage, achieving Geological Net Zero will require a substantial reduction in fossil fuel use.

The authors stress the importance of protecting and maintaining natural carbon sinks while accepting that doing so cannot compensate for ongoing fossil fuel use. Total historical CO₂ emissions determine how much a country or company has contributed to the global need for ongoing natural carbon sinks.

Part 1

We are already counting on forests and oceans to mop up our past emissions, most of which came from burning stuff we dug out of the ground. We can't expect them to compensate for future emissions as well. By mid-century, any carbon that still comes out of the ground will have to go back down, to permanent storage. That's Geological Net Zero.
Countries report both emissions and removals, but using all removals in climate targets is a recipe for continued warming. Natural carbon sinks currently clean up around half our annual emissions for free, but this ecosystem service must be kept separate from the fossil emissions driving climate change. Relabeling things will not stop global warming, say the scientists.
They stress that: It is a common assumption that removing carbon from the atmosphere to offset burning of fossil fuels is as effective as not burning fossil fuels in the first place. It is not.
Offsetting continued fossil fuel use with carbon removal will not be effective if the removal is already being counted on as part of the natural carbon cycle and if the carbon is not permanently stored. Unless we can increase transparency in national Greenhouse gas reporting and target setting, offsets will become part of the problem instead of part of the solution.
Land is limited, we rely on it for food, nature, biodiversity, leisure, water storage, and so on. It cannot offset more than a portion of fossil emissions even now, probably less in future, with worsening pressures on the biosphere such as population increase, fires, and drought.

"Giving carbon credits for natural processes that are happening anyway undermines trust in the whole idea of offsetting. We have to urgently protect natural carbon sinks, but there are more scientifically credible and equitable ways of doing this than relying on carbon offset markets."
Is anybody listening?

Myles Allen, Geological Net Zero and the need for disaggregated accounting for carbon sinks, Nature (2024). DOI: 10.1038/s41586-024-08326-8. www.nature.com/articles/s41586-024-08326-8

Part 2

Extreme heat weakens land's power to absorb carbon, analysis finds

A new European Space Agency-backed study shows that the extreme heat waves of 2023, which fueled huge wildfires and severe droughts, also undermined the land's capacity to soak up atmospheric carbon. This diminished carbon uptake drove atmospheric carbon dioxide levels to new highs, intensifying concerns about accelerating climate change.

Measurements from Hawaii's Mauna Loa Observatory showed that atmospheric carbon concentrations surged by 86% in 2023 compared to the previous year, marking a record high since tracking began in 1958.

Despite this sharp increase, fossil fuel emissions only rose by about 0.6%, suggesting that other factors, such as weakened carbon absorption by natural ecosystems, may have driven the spike.

An international team of scientists analyzed global vegetation models and satellite data to investigate the underlying causes and deliver an expedited carbon budget report for 2023.

Typically, land absorbs roughly one-third of human-generated carbon dioxide emissions. However, the team's research published in National Science Review reveals that in 2023, this capacity fell to just one-fifth of its usual level, marking the weakest land carbon sink performance in two decades.

Part 1

Widespread wildfires across Canada and droughts in the Amazon in 2023 released about the same amount of carbon to the atmosphere as North America's total fossil fuel emissions, underscoring the severe impact of climate change on natural ecosystems.

The Amazon—one of the world's most crucial carbon sinks—is showing signs of long-term strain, with some regions shifting from absorbing carbon to becoming net sources of carbon emissions.

The researchers suggest that the declining capacity of Earth's land ecosystems to absorb carbon dioxide may indicate that these natural carbon sinks are nearing their limits and no longer able to provide the mitigation service they have historically offered by absorbing half of human-induced carbon dioxide emissions.
Consequently, achieving safe global warming limits will require even more ambitious emission reductions than previously anticipated, the scientists say.
The study also highlights that current climate models might be underestimating the rapid pace and impact of extreme events, such as droughts and fires, on the degradation of these crucial carbon reservoirs.

Piyu Ke et al, Low latency carbon budget analysis reveals a large decline of the land carbon sink in 2023, National Science Review (2024). DOI: 10.1093/nsr/nwae367

Part 2

Magenta aurora over Japan

Why May 2024's aurora appeared a magenta color over Japan?

Around the world, the historic geomagnetic superstorm of late spring 2024 inspired millions of non-scientists around the world—many armed with highly sensitive smartphone cameras—to take a fantastic, unprecedented number of images of the aurora it produced.

In Japan, this widespread popular uptake of what is now quite advanced imaging technology (even if it is kept in everyone's pocket) proved to be a tremendous boon for atmospheric physicists and other scientists specializing in "space weather." It allowed them to discover why the Northern Lights over Japan appeared as a mysterious magenta color this time instead of the typical red that is observed when aurorae are visible over that country.

In early May this year, one of the most extreme geomagnetic storms in the history of recording such events hit the Earth's atmosphere. This great "storm" in space, composed of ionized particles, is what produces the aurora borealis, or Northern Lights, in the northern hemisphere and the aurora australis, or Southern Lights, in the southern hemisphere.

This time, however, the storm was so strong—the ninth most severe storm in the 110-year history of Japan's Kakioka Magnetic Observatory, one of the oldest geomagnetic stations in the world—that the polar lights could be photographed at much lower latitudes than normal.
Part 1

In Japan, space weather researchers took advantage of ordinary people taking pictures of the aurora with their smartphones to organize one of the densest citizen science observation efforts anywhere, despite being a low-latitude country where the aurora was somewhat fainter than in places like Canada or northern Europe.

The different colors of an aurora come from the emission of light from different atoms and molecules in the atmosphere when they are bombarded by the particles from space. The dramatic green hue seen in many photographs of the polar lights comes from atomic oxygen (single atoms of oxygen rather than molecular oxygen, or two oxygen atoms bound together) at the lower altitudes within the atmosphere that are visible to people. (The human eye is also just very sensitive to this color). At even lower altitudes, where atomic oxygen is less common, blue is more visible, and this comes from the greater presence of nitrogen.

At the very highest altitudes in the atmosphere, however, there is a lower concentration of atoms of any kind. The fewer collisions there result in a perception by humans of the excited atomic oxygen atoms as the color red. This is why the upper parts of the aurora curtains can appear as green fading into a scarlet hue.
At low latitudes, as in Japan, normally there is no green at all, only red because only the upper part of the aurora can be seen above the horizon.

"Yet this time, weirdly, the images revealed a very clear and dominant magenta hue to the aurora 'curtains' over Japan, not red.
To solve the mystery, the researchers quickly took to social media to encourage people to observe and report their sightings of the auroras, as well as to input data into a questionnaire asking about observation locations, time, elevation angles and other details, allowing researchers to analyze the auroras' characteristics in unprecedented detail.
Part 2

The effort resulted in an impressive 775 grassroots submissions, which the researchers then combined with satellite observations and advanced modeling techniques to explore the conditions that had led to the magenta aurora.

The elevation data from these citizen scientists proved to be particularly useful. The researchers used elevation angles to calculate the position of the aurora over time, and found that it was often a surprisingly high altitude of roughly 1,000 km above sea level—which should thus drive a red appearance. But on top of this, the time and season of year meant the atmosphere was more "preheated" ahead of the aurora, in turn driving an upwelling of ionized molecular nitrogen—what is usually responsible for a blue hue.
"Blue plus red makes us see magenta.
And the magenta was made all the more visible and vibrant by the sheer volume of solar activity, even though, ironically, the preheating would also have worked to reduce the peak brightness of the aurora."
Better understanding of magnetic storms goes beyond explaining why humans see the pretty colors of aurorae; these storms can have profound, negative impacts on satellite operations, GPS systems, power grids and even the safety of passengers and crews aboard high-altitude flights.

 Ryuho Kataoka et al, Extended magenta aurora as revealed by citizen science, Scientific Reports (2024). DOI: 10.1038/s41598-024-75184-9

Part 3

Confinement may affect how we smell and feel about food

New research  found confined and isolating environments changed the way people smelled and responded emotionally to certain food aromas.

The team in this study compared 44 people's emotional responses and perception of eight food aromas in two environmental scenarios: sitting in reclined chairs that mimic astronauts' posture in microgravity; and then in the confined setting of the International Space Station (ISS), which was simulated for participants with virtual reality goggles.
The aromas the team tested on participants were vanilla, almond, lemon, lemon myrtle, eucalyptus, peppermint, vinegar and lemongrass.

The research, published in Food Research International, builds on previous work by the team and aims to help explain why astronauts report meals taste different in space and struggle to eat their normal nutritional intake over long missions, which has been reported in the news recently.

The study has broader implications for further research to improve the diets of isolated people, including nursing home residents, by personalizing aromas to enhance the flavor of their food.
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Lemongrass consists of a more floral and earthy aroma, while the other aromas are pungent, spicy or sweet. This difference in profile may explain why lemongrass seemed less intense in the VR setting compared to the microgravity posture.
In an Earth-like setting, eating was often social, but eating in space on long missions can feel quite different.
Pilot studies [published open-access in the journal Science Talks] show that spending 10 minutes in VR can induce feelings of confinement, highlighting VR's effectiveness over other methods such as immersive screens.

"Results indicate that a remote, confined environment such as the ISS and a significant variation in personal sensitivities influence aroma perception, making certain foods smell strange.
Space studies often emphasized microgravity as the main contributing factor to food's different taste, but the team's findings underscored the impact of confined and isolated environments.
This research opens possibilities for personalized meal plans for astronauts and individuals living alone on Earth, showcasing VR's potential to explore variations in eating when stressed.
In the VR setting, participants reporting positive emotions perceived stronger aromas.This link between stress and vinegar may help explain why astronauts like to eat certain foods in microgravity that they don't normally enjoy on Earth.

Food odour perception and affective response in virtual spacecraft and microgravity body posture (1-G) – potential ground-based simulations, Food Research International (2024).

Julia Low et al, Development of a virtual reality spacecraft environment as a ground-based analog for collecting space food sensory data ('Food in Space'), Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100391

Alicia Tran et al, Exploring fundamentals of immersive environment setups on food sensory perception in space contexts, Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100403

Part 2

Scientists transform blood into regenerative materials, paving the way for personalized, 3D-printed implants

Scientists have created a new 'biocooperative' material based on blood, which has been shown to successfully repair bones, paving the way for personalized regenerative blood products that could be used as effective therapies to treat injury and disease.

Researchers have used peptide molecules that can guide key processes taking place during the natural healing of tissues to create living materials that enhance tissue regeneration. The research is published in Advanced Materials.

Most of our body tissues have evolved to regenerate ruptures or fractures with remarkable efficacy, as long as these are small in size. This healing process is highly complex. The initial stages rely on liquid blood forming the solid regenerative hematoma (RH), a rich and living microenvironment comprising key cells, macromolecules, and factors that orchestrate regeneration.
The team developed a self-assembling methodology where synthetic peptides are mixed with whole blood taken from the patient to create a material that harnesses key molecules, cells, and mechanisms of the natural healing process. In this way, it was possible to engineer regenerative materials capable of not only mimicking the natural RH, but also enhancing its structural and functional properties.
These materials can be easily assembled, manipulated, and even 3D printed while maintaining normal functions of the natural RH, such as normal platelet behavior, generation of growth factors, and recruitment of relevant cells important for healing. With this method, the team has shown the capacity to successfully repair bone in animal models using the animal's own blood.

Soraya Padilla‐Lopategui et al, Biocooperative Regenerative Materials by Harnessing Blood‐Clotting and Peptide Self‐Assembly, Advanced Materials (2024). DOI: 10.1002/adma.202407156

Scientists convert plastics into soaps and detergents

Researchers found  a way to convert certain plastics into soaps, detergents, lubricants, and other products.

  The process has two steps. It first involved using thermolysis, or breaking down a substance—in this case, plastic—by using heat. Plastic placed in a reactor built by the research team and heated to between 650 and 750 degrees Fahrenheit broke down into chemical compounds, leaving a mixture of oil, gas, and residual solids.

The key to this first step was breaking down the polypropylene and polyethylene molecules that make up plastic within a certain carbon range, and Liu and his team were able to accomplish this.

The residual solids left behind were minimal, and the gas could be captured and used as fuel. The oil, though, was the product of the most interest here.

They were also was able to functionalize, or change the chemistry, of the oil into molecules to be converted into soaps, detergents, lubricants, and other products.

These materials are stable. You could use them  to wash your hands and dishes. The researchers have used them to wash their lab glassware in the laboratory.

The process, which took less than a day, led to almost zero air pollution output, thus offering clues to a desperately needed solution to a global problem.

Nuwayo Eric Munyaneza et al, Chain-length-controllable upcycling of polyolefins to sulfate detergents, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01464-x

Researchers uncover how blood pressure drugs harm kidneys

Commonly prescribed drugs used to treat high blood pressure have been shown to, over time, wreck the kidneys' ability to filter and purify blood. How does this happen?

Researchers found that the drugs essentially rewire the kidneys to do something other than the important work of filtering blood. The kidneys start producing more of a hormone called renin; nerve endings grow excessively; cells lining the kidneys' tiny blood vessels get too large; scars form and spread; and inflammation sets in, which "can take a terrible toll on the kidney.

The result, outlined in the researchers' paper in the journal Circulation Research, is a "silent but serious" vascular disease where the kidneys become zombie-like, changing into something unwanted and unwelcome while abandoning their critical duties.

Now that they know the cause, researchers say the next step is to figure out how to use the effective blood pressure drugs known as renin-angiotensin system inhibitors—often called RAS inhibitors—while stopping the kidney-damaging effects.

RAS inhibitors, which include the generics enalapril, lisinopril, ramipril and others, are commonly prescribed when a patient is first diagnosed with high BP.

The drugs work by relaxing blood vessels and allowing blood to flow more freely. The medicines are widely used and generally considered safe, researchers say, but are not without risk. Doctors have long warned patients that certain blood pressure medications could cause kidney damage, often first noticed as a reduction in the frequency of urination, swelling in the legs or feet, or seizures.

Now that scientists understand what is causing the kidney changes, they can look for ways to stop it.

These findings may open new avenues for the prevention of adverse effects when treating hypertension.

Manako Yamaguchi et al, Transformation of the Kidney into a Pathological Neuro-Immune-Endocrine Organ, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.124.325305

High exposure to everyday chemicals linked to asthma risk in children

A new study by researchers at Kumamoto University sheds light on a potential link between exposure to certain everyday chemicals during pregnancy and the development of asthma in children. The study analyzed data from over 3,500 mother-child pairs as part of the Japan Environment and Children's Study (JECS), a large-scale nationwide research project.

researchers measured 24 types of phenols in urine samples collected from pregnant women. They then tracked the health of their children until the age of four.

The study is published in the journal Environmental Pollution.

High levels of butylparaben, a chemical commonly used in personal care products like lotions and shampoos, during early pregnanacy were associated with a 1.54-fold increase in the odds of asthma development in children (Odds Ratio: 1.54).

Exposure to 4-nonylphenol, a chemical found in some cleaning products and plastics, showed a striking gender-specific effect. Boys born to mothers exposed to this chemical had 2.09 times higher odds of developing asthma, while no such association was observed in girls.

Phenols, including parabens and alkylphenols, are widely used in consumer products for their preservative and antimicrobial properties. While their use is considered safe in small amounts, their potential as endocrine disruptors raises concerns about long-term health effects, such as the recent increase in allergenic diseases such as asthma, particularly during sensitive periods like pregnancy.

The findings highlight the importance of understanding how everyday chemical exposures might contribute to respiratory and allergic conditions in children.

Shohei Kuraoka et al, Association of phenol exposure during pregnancy and asthma development in children: The Japan Environment and Children's study, Environmental Pollution (2024). DOI: 10.1016/j.envpol.2024.124801

By exerting 'crowd control' over mouse cells, scientists make progress towards engineering tissues
Genes aren't the sole driver instructing cells to build multicellular structures, tissues, and organs. In a paper published in Nature Communications, scientists characterize the influence of another important developmental driver: cell density, or how loosely or tightly cells are packed into a given space.

In both computational models and laboratory experiments, the team of scientists used cell density as an effective tool for controlling how mouse cells pattern themselves into complex structures.

This paper represents progress towards their big picture goal of engineering synthetic tissues. Synthetic tissues could have endless medical applications, ranging from testing potential drugs or therapies to providing grafts or transplants for patients.

The study used two types of mouse cells—connective tissue cells and stem cells—engineered to carry a synthetic cellular communication system or "genetic circuit. This circuit is based on something they developed called "synNotch," which is a protein that scientists genetically engineer into a cell to serve as a "sensor."

Located on a cell's surface, this protein-based sensor recognizes an external signal that triggers the cell to respond—usually by turning on a user-defined gene.

For this particular series of experiments, the scientists used synNotch to turn on a circuit that includes green fluorescence and a way to propagate the signal further—although it could be used to turn on any gene. The fluorescence made it easy to observe cells as they formed patterns. For example, in a field of cells, scientists could create a pattern of green fluorescent rings emanating from a central point.

While conducting these experiments, the scientists noticed that genetically identical cells did not always produce the same patterns.

So that was puzzling at the beginning. When the researchers looked at it more carefully, they started seeing that there was a gradient of cell density that seemed to correlate with differences in patterning.

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Above a certain cell density, synNotch exerted a weaker effect and didn't produce the same patterns. Further complicating matters, cell density constantly shifted as cells proliferated at ever changing rates—interacting in complex ways with the synNotch genetic circuit.

The scientists then built a computational model that could predict and clarify this complex and dynamic cell behaviour. It helped guide them to think about how the cell density, proliferation rate, signaling, and all these different things conspire.

Guided by the computational model, the scientists were able to use cell density to generate a variety of predictable fluorescent patterns that developed over specific timeframes.

To understand how cell density was exerting these effects, the scientists conducted a series of experiments that yielded a surprising discovery. Greater cell density induces stress that leads to a quicker breakdown of not only synNotch in particular, but also cell surface sensors in general.

This means that cell density is a broadly applicable tool for guiding both engineered and naturally occurring cells to build a vast array of structures, tissues, and organs.

Nature has relied on cell density in conjunction with genetic circuits to generate the remarkable diversity of multicellular structures, tissues, and organs.

Now we can co-opt this same strategy to advance our efforts to build synthetic multicellular structures—and eventually tissues and organs—for regenerative medicine, say the scientists.

Nature Communications (2024). DOI: 10.1038/s41467-024-53078-8

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Research reveals even single-cell organisms exhibit habituation, a simple form of learning

Up until recently, habituation -- a simple form of learning -- was deemed the exclusive domain of complex organisms with brains and nervous systems, such as worms, insects, birds, and mammals. But a new study offers compelling evidence that even tiny single-cell creatures such as ciliates and amoebae, as well as the cells in our own bodies, could exhibit habituation akin to that seen in more complex organisms with brains.

A dog learns to sit on command, a person hears and eventually tunes out the hum of a washing machine while reading … The capacity to learn and adapt is central to evolution and, indeed, survival.

Habituation involves the lessening response to a stimulus after repeated exposure. Think of the need for a third espresso to maintain the same level of concentration you once achieved with a single shot.

Up until recently, habituation -- a simple form of learning -- was deemed the exclusive domain of complex organisms with brains and nervous systems, such as worms, insects, birds, and mammals.

But a new study, published Nov. 19 in Current Biology, offers compelling evidence that even tiny single-cell creatures such as ciliates and amoebae, as well as the cells in our own bodies, could exhibit habituation akin to that seen in more complex organisms with brains.

This finding opens up an exciting new mystery for us: How do cells without brains manage something so complex?

The results add to a small but growing body of work on this subject. Earlier work led by Gunawardena found that a single-cell ciliate showed avoidance behavior, not unlike the actions observed in animals that encounter unpleasant stimuli.

Instead of studying cells in a lab dish, the scientists used advanced computer modeling to analyze how molecular networks inside ciliate and mammalian cells respond to different patterns of stimulation. They found four networks that exhibit hallmarks of habituation present in animal brains.

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These networks shared a common feature: Each molecular network had two forms of "memory" storage that captured information learned from the environment. One memory decayed much faster than the other -- a form of memory loss necessary for habituation, the researchers noted. This finding suggests that single cells process and remember information over different time spans.

Studying habituation in single cells could help propel understanding of how learning in general works, the researchers said. The findings also cast the humble single-cell creatures in a new, more tantalizing light: They are not merely molecular machines packed in microscopic bodies, but they are also agents that can learn.

Practical applications of this work:

One daring idea would be to apply the concept of habituation to the relationship between cancer and immunity.

Tumors are notoriously good evaders of immune surveillance because they trick immune cells into viewing them as innocent bystanders. In other words, the immune cells responsible for recognizing cancer may get somehow habituated to the presence of a cancer cell -- the immune cell gets used to the stimulus and no longer responds to it.

If we knew how these false perceptions get encoded in immune cells, we may be able to re-engineer them so that immune cells begin to perceive their environments correctly, the tumor becomes visible as malign, and they get to work.

Lina Eckert, Maria Sol Vidal-Saez, Ziyuan Zhao, Jordi Garcia-Ojalvo, Rosa Martinez-Corral, Jeremy Gunawardena. Biochemically plausible models of habituation for single-cell learning. Current Biology, 2024; DOI: 10.1016/j.cub.2024.10.041

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Astronauts found to process some tasks slower in space, but no signs of permanent cognitive decline

A stay in space exerts extreme pressures on the human body. Astronauts' bodies and brains are impacted by radiation, altered gravity, challenging working conditions, and sleep loss—all of which could compromise cognitive functioning. At the same time, they are required to perform complex tasks, and minor mistakes can have devastating consequences.

Working with 25 astronauts who spent an average of six months on the International Space Station (ISS), researchers  have examined changes in a wide range of cognitive performance domains. This dataset makes up the largest sample of cognitive performance data from professional astronauts published to date.

The research shows that there is no evidence of any significant cognitive impairment or neurodegenerative decline in astronauts spending six months on the ISS. Living and working in space was not associated with widespread cognitive impairment that would be suggestive of significant brain damage.

The results showed that responses to tasks assessing processing speed, working memory, and attention were slower than on Earth, but they were no less accurate. These changes, however, did not persist equally long.

Slowed performance on attention, for example, was only observed early during the mission, while slowed performance on processing speed did not return to baseline levels until after the mission ended and the crew were back on Earth.

Overall, astronauts' cognitive performance was stable, and the researchers did not find evidence that would suggest damage to the central nervous system during a six-month space mission.

Cognitive Performance in ISS Astronauts on 6-month Low Earth Orbit Missions, Frontiers in Physiology (2024). DOI: 10.3389/fphys.2024.1451269

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