Chameleon-inspired coating could cool and warm buildings through the seasons

As summer turns to fall, many people will be turning off the air conditioning and firing up heaters instead. But traditional heating and cooling systems are energy-intensive, and because they typically run on fossil fuels, they aren't sustainable. Now, by mimicking a desert-dwelling chameleon, a research team reporting in Nano Letters has developed an energy-efficient, cost-effective coating. The material could keep buildings cool in the summers—or warm in the winters—without additional energy.

Many desert creatures have specialized adaptations to allow them to survive in harsh environments with large daily temperature shifts. For example, the Namaqua chameleon of southwestern Africa alters its color to regulate its body temperature as conditions change. The critters appear light gray in hot temperatures to reflect sunlight and keep cool, then turn a dark brown once they cool down to absorb heat instead.

This unique ability is a naturally occurring example of passive temperature control—a phenomenon that could be adapted to create more energy-efficient buildings. But many systems, such as cooling paints or colored steel tiles, are only designed to keep buildings either cool or warm, and can't switch between "modes."

Inspired by the Namaqua chameleon, researchers wanted to create a color-shifting coating that would adapt as outside temperatures fluctuate. To make the coating, researchers mixed thermochromic microcapsules, specialized microparticles and binders to form a suspension, which they sprayed or brushed onto a metal surface. When heated to 68 degrees Fahrenheit, the surface began to change from dark to light gray. Once it reached 86 degrees, the light-colored film reflected up to 93% of solar radiation. Even when heated above 175 degrees for an entire day, the material showed no signs of damage. Next, the team tested it alongside three conventional coatings—regular white paint, a passive radiative cooling paint and blue steel tiles—in outdoor tests on miniature, doghouse-sized buildings throughout all four seasons.

Part 1

• In winter, the new coating was slightly warmer than the passive radiative cooling system, though both maintained similar temperatures in warmer conditions.
• In summer, the new coating was significantly cooler than the white paint and steel tiles.
• During spring and fall, the new coating was the only system that could adapt to the widely fluctuating temperatures changes, switching from heating to cooling throughout the day.

The researchers say that this color-changing system could save a considerable amount of energy for regions that experience multiple seasons, while still being inexpensive and easy to manufacture.

"Warm in Winter and Cool in Summer" Scalable Biochameleons Inspired Temperature Adaptive Coating with Easy Preparation and Construction, Nano Letters (2023). DOI: 10.1021/acs.nanolett.3c02733

Part 2

Nanotechnology in the fight against viruses

Newly emerging and recurrent cases of viral infections constitute a significant problem and a huge challenge to public health. Most countries prevent or control acute viral infections through widespread vaccination and improved sanitation. As a result, measles, yellow fever, and rabies cases rarely occur now.

But these days very frequently, new viral infections, symptoms and infections are being  reported. But researchers are trying to fight these viral infections with nanotechnology that can solve current problems related to the prevention, treatment, and diagnosis of viral infections.

Most attention is paid to the synthesis of new drugs and vaccines based on nanocarriers, with increased effectiveness and reduced side effects, the design of personal protective equipment (masks, gloves, medical clothing) and self-disinfecting surfaces, as well as strategies for the development of nanobiosensors enabling early detection of viral infection.

The results of research conducted on a laboratory scale are very promising. However, when thinking about the commercialization of medical products based on nanotechnology, one should consider how their cost can be reduced and how they can be made more reliable compared to existing solutions.

This is one such paper: Joanna Goscianska et al, Nanoscience versus Viruses: The SARS‐CoV‐2 Case, Advanced Functional Materials (2021). DOI: 10.1002/adfm.202107826

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Deep sea mystery of the Lebensspuren

Regeneration across complete spinal cord injuries reverses paralysis

When the spinal cords of mice and humans are partially damaged, the initial paralysis is followed by the extensive, spontaneous recovery of motor function. However, after a complete spinal cord injury, this natural repair of the spinal cord doesn't occur and there is no recovery. Meaningful recovery after severe injuries requires strategies that promote the regeneration of nerve fibers, but the requisite conditions for these strategies to successfully restore motor function have remained elusive till recently.

Five years ago, some researchers demonstrated that nerve fibres can be regenerated across anatomically complete spinal cord injuries. But they also realized this wasn't enough to restore motor function, as the new fibers failed to connect to the right places on the other side of the lesion.

Now the scientists used state-of-the-art equipment to run in-depth analyses and identity which type of neuron is involved in natural spinal-cord repair after partial spinal cord injury.

Their  observations using single-cell nuclear RNA sequencing not only exposed the specific axons that must regenerate, but also revealed that these axons must reconnect to their natural targets to restore motor function.

Their discovery informed the design of a multipronged gene therapy. The scientists activated growth programs in the identified neurons in mice to regenerate their nerve fibers, upregulated specific proteins to support the neurons' growth through the lesion core, and administered guidance molecules to attract the regenerating nerve fibers to their natural targets below the injury.

Mice with anatomically complete spinal cord injuries regained the ability to walk, exhibiting gait patterns that resembled those quantified in mice that resumed walking naturally after partial injuries. This observation revealed a previously unknown condition for regenerative therapies to be successful in restoring motor function after neurotrauma.

Scientists now think a complete solution for treating spinal cord injury will require both approaches—gene therapy to regrow relevant nerve fibers, and spinal stimulation to maximize the ability of both these fibers and the spinal cord below the injury to produce movement.

While many obstacles must still be overcome before this gene therapy can be applied in humans, the scientists have taken the first steps towards developing the technology necessary to achieve this feat in the years to come.

Jordan W. Squair et al, Recovery of walking after paralysis by regenerating characterized neurons to their natural target region, Science (2023). DOI: 10.1126/science.adi6412. www.science.org/doi/10.1126/science.adi6412

Smart speaker lets users mute different areas of a room

In virtual meetings, it's easy to keep people from talking over each other. Someone just hits mute. But for the most part, this ability doesn't translate easily to recording in-person gatherings. In a bustling cafe, there are no buttons to silence the table beside you.

The ability to locate and control sound—isolating one person talking from a specific location in a crowded room, for instance—has challenged researchers, especially without visual cues from cameras.

A team of researchers has developed a shape-changing smart speaker, which uses self-deploying microphones to divide rooms into speech zones and track the positions of individual speakers. With the help of the team's deep-learning algorithms, the system lets users mute certain areas or separate simultaneous conversations, even if two adjacent people have similar voices.

Like a fleet of Roombas, each about an inch in diameter, the microphones automatically deploy from and then return to a charging station. This allows the system to be moved between environments and set up automatically. In a conference room meeting, for instance, such a system might be deployed instead of a central microphone, allowing better control of in-room audio.

Creating Speech Zones Using Self-distributing Acoustic Swarms, Nature Communications (2023). DOI: 10.1038/s41467-023-40869-8. www.nature.com/articles/s41467-023-40869-8

Turning a cockroach into a cyborg without injuring it

Where do spammers get your details?

Each time you enter your email address or phone number into an e-commerce website, you may be handing it to spammers. But sometimes you may even receive spam from entities you don't recognize. That's because businesses will often transfer customers' contact information to related companies, or sell their data to third parties such as data brokers.

Some entities also use "address-harvesting" software to search the internet for electronic addresses that are captured in a database. The collector then uses these addresses directly, or sells them to others looking to send spam.

Most countries have prohibitions.

If the receiver consented to these types of messages, the prohibition does not apply. When you buy goods or services from a company, you will often see a request to click on a "yes" button to receive marketing promotions. Doing so means you have consented. On the other hand, if your phone or inbox are hit by commercial messages you haven't agreed to receive, that is a breach of the Spam Act by the sender. If you originally signed up to receive the messages, but then unsubscribed and the messages kept coming after five business days, that is also illegal. Senders must also include a functioning unsubscribe facility in every commercial message they send. Spammers can be penalized for breaches of the Spam Act.

It's worth noting that messages from political parties, registered charities and government bodies aren't prohibited—nor are messages from educational institutions to students and former students. So while you might consider these messages as "spam", they can legally be sent freely without consent. Factual messages (without marketing content) from businesses are also legal as long as they include accurate sender details and contact information.

Part 1

If you want to stop spam,

1. use a spam filter and block spammers—email and telecommunications providers often supply useful tools as part of their services
2. unsubscribe from any emails you no longer want to receive—even if you originally agreed to receive them
3. remove as much of your contact details from websites as you can and always restrict the sharing of your personal information (such as name, birth date, email address and mobile number) when you can—beware of pre-ticked boxes asking for your consent to receive marketing emails
4. install cybersecurity updates for your devices and software as you get them
5. always think twice about opening emails or clicking on links, especially for messages promising rewards or asking for personal information—if it looks too good to be true, it probably is
6. use multi-factor authentication to access online services so even if a scam compromises your login details, it will still be difficult for hackers to break into your accounts
7. report spam to your email and telecommunications providers.

Source: https://theconversation.com/why-do-i-get-so-much-spam-and-unwanted-...

Brain sensitivity to insulin may be modulated by menstrual cycle

A combined team of diabetes specialists  has found evidence that suggests brain sensitivity to insulin may be modulated by the menstrual cycle in women.

In their study, reported in the journal Nature Metabolism, the group conducted a clinical trial involving monitoring the insulin levels of female volunteers.

Prior research has suggested that the presence of insulin in the brain can lead to changes in eating behavior, whole-body metabolism and fat storage. How this works is not well understood. Making things even murkier, as the researchers note, is that virtually all prior research in this area has involved testing the impact of insulin on the brains of men.

In this new effort, the research team sought to learn more about the impact of insulin on women's brains. To that end, they conducted a clinical trial that involved testing the impact of insulin on the brains of 11 female volunteers during two time periods; during their first day of ovulation, and just after they had ovulated.

To measure the impact of insulin on their brains, the volunteers underwent hyperinsulinemic-euglycemic clamps—a procedure that can be used to measureinsulin sensitivity. Some of the women were also given intranasal insulin doses during the procedure while others received a placebo. The researchers found that during the first day of ovulation, the brain was more sensitive to the insulin, but not during the days just after ovulation.

Next, the research team administered MRI scans to 15 different female volunteers to learn more about the impact of insulin on the hypothalamus during menstrual cycles. They found the same results—the women exhibited higher hypothalamus sensitivity to insulin just prior to the onset of ovulation but not afterward. The researchers suggest their findings explain why so many women experience hunger just prior to getting their period, why their metabolism slows and why weight gain is so much more likely. The researchers suggest that the female body reacts this way as a means of storing up energy to sustain a pregnancy, should it occur.

 Julia Hummel et al, Brain insulin action on peripheral insulin sensitivity in women depends on menstrual cycle phase, Nature Metabolism (2023). DOI: 10.1038/s42255-023-00869-w

Nils B. Kroemer, Metabolic tuning during the menstrual cycle, Nature Metabolism (2023). DOI: 10.1038/s42255-023-00867-y

New research adds evidence to the benefits of ginger supplements for treating autoimmune diseases

New research has revealed a potentially important role ginger supplements can play in controlling inflammation for people living with autoimmune diseases.

The research published in JCI Insight focused on studying the impact of ginger supplementation on a type of white blood cell called the neutrophil. The study was especially interested in neutrophil extracellular trap (NET) formation, also known as NETosis, and what it may mean for controlling inflammation.

The study found ginger consumption by healthy individuals makes their neutrophils more resistant to NETosis. This is important because NETs are microscopic spider web-like structures that propel inflammation and clotting, which contribute to many autoimmune diseases, including lupus, antiphospholipid syndrome and rheumatoid arthritis.

There are a lot of diseases where neutrophils are abnormally overactive. Now researchers found that ginger can help to restrain NETosis, and this is important because it is a natural supplement that may be helpful to treat inflammation and symptoms for people with several different autoimmune diseases.

In a clinical trial, the researchers found that daily intake of a ginger supplement for seven days (20 mg of gingerols/day) by healthy volunteers boosted a chemical inside the neutrophil called cAMP. These high levels of cAMP then inhibited NETosis in response to various disease-relevant stimuli.

There are not a lot of natural supplements, or prescription medications for that matter, that are known to fight overactive neutrophils. Researchers think ginger may have a real ability to complement treatment programs that are already underway. The goal is to be more strategic and personalized in terms of helping to relieve people's symptoms.

 Ginger intake suppresses neutrophil extracellular trap formation in autoimmune mice and healthy humans, JCI Insight (2023).

https://insight.jci.org/articles/view/172011

Urban light pollution linked to smaller eyes in birds: Study

 The bright lights of big cities could be causing an evolutionary adaptation for smaller eyes in some birds, a new study indicates.

Researchers found that two common songbirds, the Northern Cardinal and Carolina Wren, that live year-round in the urban core of San Antonio, Texas, had eyes about 5% smaller than members of the same species from the less bright outskirts. Researchers found no eye-size difference for two species of migratory birds, the Painted Bunting and White-eyed Vireo, no matter which part of the city they lived in for most of the year.

The findings, published in Global Change Biology, have implications for conservation efforts amid the rapid decline of bird populations.

This study shows that residential birds may adapt over time to urban areas, but migratory birds are not adapting, probably because where they spend the winter—they are less likely to have the same human-caused light and noise pressures. It may make it more difficult for them to adjust to city life during the breeding season.

Todd M. Jones, Alfredo P. Llamas, Jennifer N. Phillips. Phenotypic signatures of urbanization? Resident, but not migratory, songbird eye size varies with urban‐associated light pollution levels. Global Change Biology, 2023; DOI: 10.1111/gcb.16935

Why You Didn't Get Your Dad's Mitochondria

Virtually every animal on Earth can thank their mother for the energy that fuels each of their cells. The power is generated in a part of the cell known as the mitochondria, and this organelle is made entirely from a genetic recipe laid out in your mother's DNA.

A father's mitochondrial DNA, or mtDNA, plays no part. Yet the precise point at which dad's mitochondrial genes are given the heave-ho isn't a clear-cut story, with different studies supporting a breakdown in the egg's cytoplasm, and a severe edit in the sperm as it's being formed. A recent study that sequenced the genes in human sperm cells could detect no intact mtDNA before fertilization, lending support to an early chop. While each sperm cell contained about 100 mitochondria of its own, a team of researchers  found no trace of male mtDNA within the mitochondria. The sperm also lacked the transcription factors needed to maintain mtDNA. "We conclude," the authors write, "that the mature human spermatozoa are essentially devoid of mtDNA, consistent with maternal inheritance of the mitochondrial genome in mammals."

Of course, male sex cells still contribute nuclear DNA to their offspring, and the human nuclear genome is billions of times larger than the mitochondrial genome. Even still, mutations in the latter genome are associated with a diversity of diseases and aging processes, which suggests it is quite important for health and function.

So why is it only mom's mtDNA that gets passed down?

Part 1

So why is it only mom's mtDNA that gets passed down?

One hypothesis has to do with the mitochondrial genome's relatively high mutation rate compared to the nuclear genome. Each cell in the body contains numerous mitochondria, which get separated into daughter cells the parent cell splits.

Because sperm cells rapidly churn through their energy trying to reach a human egg for fertilization, their mtDNA – if it did exist – would probably accumulate a bunch of mutations.

Eggs pass on really good mtDNA at least partly because they don't use mitochondria as a source of energy.

The findings do not explain why, in rare circumstances, scientists have found mtDNA transmission in some humans that looks as though it came from both the father and the mother. But it might help experts better understand some fertility disorders, which can be passed down through eggs or sperm. In recent years, scientists have started to find ways to target specific mutations in mitochondrial DNA so they aren't inherited by offspring. Worldwide, in fact, several children have been born with DNA from three different people, after their parents sought cutting-edge mitochondrial replacement therapy. The incredibly unique babies have nuclear DNA that derives from the fertilization of a sperm and an egg, like any other child, but their mitochondrial DNA comes from the egg of a separate female donor. "Maternal inheritance of mtDNA is a major paradigm that guides the existence and evolution of the vast majority of species," the authors of the recent study conclude, "however, the molecular basis of this phenomenon and its benefits have remained unclear."

For such a foundational part of life, it's incredible we don't know more about where our genes come from.

https://www.nature.com/articles/s41588-023-01505-9

Part 2

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RNA has been recovered from an extinct species for the first time

A new study shows the isolation and sequencing of more than a century-old RNA molecules from a Tasmanian tiger specimen preserved at room temperature in a museum collection. This resulted in the reconstruction of skin and skeletal muscle transcriptomes from an extinct species for the first time.

The researchers note that their findings have relevant implications for international efforts to resurrect extinct species, including both the Tasmanian tiger and the wooly mammoth, as well as for studying pandemic RNA viruses.

The Tasmanian tiger, also known as the thylacine, was a remarkable apex carnivorous marsupial that was once distributed all across the Australian continent and the island of Tasmania. This extraordinary species found its final demise after European colonization, when it was declared as an agricultural pest and a bounty of £1 per each full-grown animal killed was set by 1888. The last known living Tasmanian tiger died in captivity in 1936 at the Beaumaris Zoo in Hobart, Tasmania. Recent efforts in de-extinction have focused on the Tasmanian tiger, as its natural habitat in Tasmania is still mostly preserved, and its reintroduction could help recovering past ecosystem equilibriums lost after its final disappearance. However, reconstructing a functional living Tasmanian tiger not only requires a comprehensive knowledge of its genome (DNA) but also of tissue-specific gene expression dynamics and how gene regulation worked, which are only attainable by studying its transcriptome (RNA). Resurrecting the Tasmanian tiger or the wooly mammoth is not a trivial task, and will require a deep knowledge of both the genome and transcriptome regulation of such renowned species, something that only now is starting to be revealed.

The researchers behind this study have sequenced, for the first time, the transcriptome of the skin and skeletal muscle tissues from a 130-year-old desiccated Tasmanian tiger specimen preserved at room temperature in the Swedish Museum of Natural History in Stockholm. This led to the identification of tissue-specific gene expression signatures that resemble those from living extant marsupial and placental mammals. The recovered transcriptomes were of such good quality that it was possible to identify muscle- and skin-specific protein coding RNAs, and led to the annotation of missing ribosomal RNA and microRNA genes, the later following MirGeneDB recommendations.

Emilio Marmol-Sanchez et al, Historical RNA expression profiles from the extinct Tasmanian tiger, Genome Research (2023). DOI: 10.1101/gr.277663.123

Cross-species virus transmission found in several species of small furry animals

Research led by multiple institutions in China has examined how small, furry, viral vectors affect the spread and evolution of viruses. They report the identification of 669 viruses, including 534 novel viruses, greatly expanding our knowledge of the mammalian virome, including previously unknown coronaviruses and orthorubulaviruses.

In their paper, "Host traits shape virome composition and virus transmission in wild small mammals," published in Cell, the team used meta-transcriptomic sequencing of internal organ and fecal samples from 2,443 wild bats, rodents, and shrews from four Chinese habitats. Viruses were identified in nearly all animals studied.

Researchers identified viruses related to known human or domestic animal pathogens (e.g., Rotavirus A, Seoul virus, Wenzhou mammarenavirus), including coronaviruses, which have caused diseases like SARS and COVID-19. There were also newly identified viruses from the orthorubulaviruses, porcine epidemic diarrhea virus (PEDV), swine acute diarrhea syndrome coronaviruses (SADS-CoVs), and SARS-related coronaviruses.

The study provided robust evidence of cross-species virus transmission. For instance, viruses were found in multiple species of wild small mammals, indicating that these viruses can move between different animal species, potentially including humans.

The team observed cross-species virus transmission at taxonomic levels across species, genus, family, and order, where the same virus was found in three or more mammalian species. Viruses with multi-organ distributions within hosts were more likely to be found in other host species. This suggests that if a virus is present in multiple internal organs, it has a higher chance of spreading to other species.

Bats are often considered to harbor more viruses than rodents. Of the animals sampled in the study, bats did have the highest richness, followed by rodents and shrews. While the total number of viruses identified in bats was more than that in rodents, the average number of viruses identified per species of bats and rodents was similar.

Yan-Mei Chen et al, Host traits shape virome composition and virus transmission in wild small mammals, Cell (2023). DOI: 10.1016/j.cell.2023.08.029

Scam awareness found to be best defense for older adults facing fraudster phone calls

Research  has looked into the susceptibility of older adults to scammers. In a paper, "Vulnerability of Older Adults to Government Impersonation Scams," published in JAMA Network Open, researchers tested 644 older adults with an experiment designed to mimic a government impersonation scam.

Participants averaged age 85.6 and were part of the Rush Memory and Aging Project (MAP), an ongoing cohort study of common chronic conditions related to aging. As part of the experiment, they were exposed to deceptive materials through mailers, emails, and phone calls by a live agent, mimicking a government impersonation scam.

Results were classified by three engagement groups: no engagement, engagement with skepticism, and conversion (those who engaged without skepticism).

Of the 644 participants, 441 (68.5%) did not engage, 97 (15.1%) engaged but raised skepticism, and 106 (16.4%) comprised the conversion group. Of those converted, nearly three-quarters provided personal information.

The research revealed that factors like cognition, financial literacy, and awareness of fraud scams were associated with the type of engagement. Those in the skeptical engagement group had the highest cognitive scores and financial literacy, while the conversion group had the lowest scam awareness.

According to the Federal Trade Commission, phone calls are the most common and most effective method used by fraudsters for targeting older adults.

Lei Yu et al, Vulnerability of Older Adults to Government Impersonation Scams, JAMA Network Open (2023). DOI: 10.1001/jamanetworkopen.2023.35319

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AI predicts sea surface temperature cooling during tropical cyclones

Tropical cyclones are extreme weather events, characterized by a circular form and formation over warm tropical oceans experiencing low atmospheric pressure, high winds and heavy rain. Tropical storms exceed 39 miles per hour (mph), while hurricanes experience sustained winds of 74mph and above.

The warm waters fuel the continuation of the cyclone, consequently cooling the surface of the ocean, and high wind speeds increase currents. The latter results in mixing of the layers of the ocean, bringing deeper and cooler water to the surface. In doing so, this can help to reduce the warm water fuel to cyclones, causing them to slow down or even cease altogether.

New research published in Geophysical Research Letters has turned towards technology to model the effects of tropical cyclones on oceans, in particular sea surface temperatures. This is important as the temperature can impact wider ecosystem responses, as well as the organisms that call the oceans home.

The machine learning-based random forest method used data from a 20-year period beginning in 1998 to train the system and help predict the evolution of sea surface temperature over time and space within the northwest Pacific Ocean (equator to 30°N, 100–160°E), one of the most active zones for tropical cyclones.

The research work showed that stronger intensity, larger and slower-moving tropical cyclones in areas with a shallow mixed ocean layer tend to have a greater cooling effect on the surface waters. Storm intensity and speed have a greater local effect, while the overall size of the cyclone, pre-storm ocean mixed layer depth and sea surface temperature impact the cooling effect over a larger area. 

Hongxing Cui et al, Predicting Tropical Cyclone‐Induced Sea Surface Temperature Responses Using Machine Learning, Geophysical Research Letters (2023). DOI: 10.1029/2023GL104171

Antimatter falls downward like normal matter: Study reveals gravity's effect on matter's elusive twin

Physicists studying antihydrogen—an anti-proton paired with an antielectron, or positron—have conclusively shown that gravity pulls it downward and does not push it upward. At least for antimatter, antigravity doesn't exist.

The experimental results have been reported in the Sept. 28 issue of the journal Nature by a team representing the Antihydrogen Laser Physics Apparatus (ALPHA) collaboration at the European Center for Nuclear Research (CERN) in Geneva, Switzerland.

The gravitational acceleration of antimatter that the team comes up with is close to that for normal matter on Earth: 1 g, or 9.8 meters per second per second (32 feet per second per second). More precisely, it was found to be within about 25% (one standard deviation) of normal gravity.

It surely accelerates downwards, and it's within about one standard deviation of accelerating at the normal rate.

Albert Einstein's theory of general relativity, though conceived before antimatter was discovered in 1932, treats all matter identically, implying that antimatter and matter respond the same to gravitational forces. All normal matter, such as protons, neutrons and electrons, have anti-particles that bear the opposite electrical charge and, when they encounter their normal matter counterpart, annihilate completely.

Part 1

An artist's conceptual rendering of the antihydrogen atoms contained within the magnetic trap of the ALPHA-g apparatus. As the field strength at the top and bottom of the magnetic trap is reduced, the antihydrogen atoms escape, touch the chamber walls and annihilate. Most of the annihilations occur beneath the chamber, showing that gravity is pulling the antihydrogen down.

Jeffrey Hangst, Observation of the effect of gravity on the motion of antimatter, Nature (2023). DOI: 10.1038/s41586-023-06527-1. www.nature.com/articles/s41586-023-06527-1

Anna Soter, Free-falling antihydrogen reveals the effect of gravity on antimatter, Nature (2023). DOI: 10.1038/d41586-023-02930-w , www.nature.com/articles/d41586-023-02930-w

Part 2

 Why our skin feels 'tight' after washing

When we wash our face with a cleanser, our skin can start to feel tight. With the application of a favorite moisturizer, that feeling often goes away. This perception of our skin might seem subjective, but researchers recently revealed the mechanism behind these feelings.

Their work, published in PNAS Nexus, demonstrates how mechanical changes at the outer surface of our skin translate into sensations and provides a quantitative approach for determining how people will perceive their skin after using a moisturizer or cleanser.

Our skin is the largest organ in our body and it's constantly exposed to the environment around us. The outermost layer of our skin—the stratum corneum—acts as a barrier to keep out unwanted chemicals and bacteria and to keep in moisture. When we use a harsh cleanser, it strips away some of the lipids that hold in moisture, causing the stratum corneum to contract. A good moisturizer increases the water content of the stratum corneum, causing it to swell.

 The mechanical forces created by this shrinking or swelling propagate through the skin to reach mechanoreceptors—sensory receptors that turn mechanical force into neurological signals—below the epidermis, which then fire off signals to the brain that we interpret as a feeling of skin tightness.

The researchers studied the effects of nine different moisturizing formulas and six different cleansers on donor skin samples from three locations on the human body—cheek, forehead, and abdomen. They measured changes in the stratum corneum in the lab and then fed that information into a sophisticated model of human skin to predict the signals that the mechanoreceptors would send.

Ross Bennett-Kennett et al, Sensory neuron activation from topical treatments modulates the sensorial perception of human skin, PNAS Nexus, (2023) DOI: 10.1093/pnasnexus/pgad292. academic.oup.com/pnasnexus/art … /2/9/pgad292/7278834

Ultrasound enables gene delivery throughout the brain

Researchers tested the safety and feasibility of gene delivery to multiple brain regions using a noninvasive, ultrasound-based technique in rodents, and their findings suggest that the efficiency of gene delivery improves within each targeted site when more sites are opened.

The work used focused ultrasound energy to safely make the blood-brain barrier permeable. The technique is known as focused ultrasound blood-brain barrier opening (FUS-BBBO). 

The procedure also permits the passage of proteins and other small molecules in the other direction—that is, from the brain into the bloodstream—where they can be readily sampled.

Many disorders affect large brain regions or the entire brain, but delivery of gene therapy to these regions is difficult. 

When a gene-delivery vector is injected into the brain with a needle, it often only diffuses a few millimeters. To treat the entire brain, one would need to perform thousands of injections, which would be difficult and possibly harmful. With FUS-BBBO, such surgical delivery could be circumvented.

Researchers now tested the efficiency and safety of opening 105 sites simultaneously with positive results in most regions of the brain. Surprisingly, their findings suggest that the efficiency of gene delivery improves within each targeted site when more sites are opened.

 Shirin Nouraein et al, Acoustically targeted noninvasive gene therapy in large brain volumes, Gene Therapy (2023). DOI: 10.1038/s41434-023-00421-1

An adhesive and stretchable epicardial patch to precisely monitor the heart's activity

Epicardial patches are carefully engineered tissue patches that can be placed near or on a patient's heart. These devices can help doctors to diagnose and treat a variety of heart conditions, including arrhythmia and heart attacks (i.e., myocardial infarctions).

In recent years, several engineers and medical researchers have been trying to develop these devices, yet many solutions proposed so far are not ideal. Specifically, most epicardial patches created so far are designed to be affixed onto the heart via a medical procedure known as "suturing," which can be both challenging and risky. Researchers recently developed an alternative epicardial patch that could be much easier to apply in clinical settings. This patch, introduced in Nature Electronics, is both stretchable and adhesive; thus, it does not need to be affixed onto a patient's heart through the suturing process.

Considering the highly irregular surface of the heart, the existing devices with low adhesiveness often become detached due to continuous cardiac contraction/relaxation in long term. To overcome such issues, facile and instantaneous and even robust adhesion to cardiac tissues is essential. Furthermore, when attached to the heart for an extended period, the materials used in epicardial devices should be exceptionally soft to avoid causing any tissue compression.

Researchers set out to develop a new adhesive epicardial patch that effectively overcomes the limitations of previously proposed designs. The patch they created now can be instantly attached to tissue on the heart's surface and could easily be fabricated on a large-scale.

Notably, their patch does not exert any unnecessary pressure on the heart's tissue for extended periods of time, which could improve both its safety and efficacy. It is comprised of three different but co-existing materials, namely a liquid-phase conducting composite, a network-shaped substrate, and an ionic adhesive.

The combination of these materials eliminates the need to suture the patch to the heart, making it easy to implement for medical professionals with varying degrees of experience, while also reducing the risk of complications associated with the suturing procedure.

 Heewon Choi et al, Adhesive bioelectronics for sutureless epicardial interfacing, Nature Electronics (2023). DOI: 10.1038/s41928-023-01023-w

Recessive genes make the carrot colour orange

A new study of the genetic blueprints of more than 600 types of carrot shows that three specific genes are required to give carrots an orange color. Surprisingly, these three required genes all need to be recessive, or turned off. The paper's findings shed light on the traits important to carrot improvement efforts and could lead to better health benefits from the vegetable.

Normally, to make some function, you need genes to be turned on. In the case of the orange carrot, the genes that regulate orange carotenoids—the precursor of vitamin A that have been shown to provide health benefits—need to be turned off.

According to the researchers, orange carrot could have resulted from white and yellow carrot crosses, as white and yellow carrots are at the base of the phylogenetic tree for the orange carrot. Also, carotenoids got their name because they were first isolated from carrots.

Population genomics identifies genetic signatures of carrot domestication and improvement and uncovers the origin of high carotenoid orange carrots, Nature Plants (2023). DOI: 10.1038/s41477-023-01526-6

Fire- safe fuel!

 Chemical engineers have designed a fuel that ignites only with the application of electric current. Since it doesn't react to flames and cannot start accidental fires during storage or transport, it is a "safe" liquid fuel.

The fuel we're normally using is not very safe. It evaporates and could ignite, and it's difficult to stop that. 

It is much easier to control the flammability of our fuel and stop it from burning when we remove voltage.

When fuel combusts, it is not the liquid itself that burns. Instead, it is the volatile fuel molecules hovering above the liquid that ignite on contact with oxygen and flame. Removing an oxygen source will extinguish the flame, but this is difficult to do outside of an engine.

If you throw a match into a pool of gasoline on the ground, it's the vapor of the gas that's burning. You can smell that vapor and you instantly know it's volatile. If you can control the vapour, you can control whether the fuel burns.

The base of the new fuel is an ionic liquid, which is a form of liquified salt. It is similar to the salt we use to flavour food, which is sodium chloride. The one researchers used for this project has a lower melting point than table salt, low vapour pressure, and is organic.

Once in the lab, the research team modified the ionic liquid's formula, replacing the chlorine with perchlorate. Then, they used a cigarette lighter to see if the resulting liquid would burn. 

Next the team tried an application of voltage followed by a lighter flame, which did ignite. Once they shut off the current, the flame was gone, and they were able to repeat that process over and over again—applying voltage, seeing smoke, lighting the smoke so it burned, then turning it off. It's a system they could start and stop very quickly.

Adding more voltage to the liquid resulted in larger flames with more energy output. As such the approach could also act like a metering or throttling system in an engine.

Prithwish Biswas et al, Electrochemical Modulation of the Flammability of Ionic Liquid Fuels, Journal of the American Chemical Society (2023). DOI: 10.1021/jacs.3c04820

Scientists zero in on the life-threatening fungus, Candida auris' ability to stick

In 2009, a mysterious fungus emerged seemingly from out of thin air, targeting the most vulnerable among us. The fungus in question poses a very real threat. Scientists are trying to figure out what makes the life-threatening fungus Candida auris tick—and why even the best infection control protocols in hospitals and other care settings often fail to get rid of it.

Researchers have now zeroed in on C. auris' uncanny ability to stick to everything from skin to catheters and made a startling discovery.

They discovered that C. auris is unlike any other known fungus in that it employs a type of protein, called an adhesin, that acts very similar to those used by oceanic organisms, such as barnacles and mollusks.

The new adhesin is only present in C. auris so we don't know where it came from evolutionarily. It doesn't look like it came from any other organisms by sequence similarity. The bonds formed by Scf1, they revealed, are cation-pi bonds, which are among the strongest non-covalent chemical bonds in nature.

Furthermore, the team discovered that SCF1 was associated with increased colonization and an enhanced ability to cause disease. Using mouse models, they demonstrated that a loss of both SCF1 and IFF4109 diminished the ability of a strain of C. auris to colonize skin and an in-dwelling catheter. What's more, strains designed to over express SCF1 saw enhanced virulence and more fungal lesions.

It could be that adhesin is required to get attached to blood vessels,  or maybe it changes the host-receptor interactions which has been true for the related fungus Candida albicans, but we don't know in this case yet.

Darian J. Santana et al, A Candida auris –specific adhesin, Scf1 , governs surface association, colonization, and virulence, Science (2023). DOI: 10.1126/science.adf8972

Researchers find a cancer enhancer in the genome that drives tumor cell growth

Researchers have found that cancer cells can enhance tumor growth by hijacking enhancer DNA normally used when tissues and organs are formed. The mechanism, called enhancer reprogramming, occurs in bladder, uterine, breast and lung cancer, and could cause these types of tumors to grow faster in patients.

The results also pinpoint the role that specific proteins play in regulating the enhancer region which may lead to improved treatments for these cancer types. Living cells, even cancer cells, follow instructions in the genome to turn genes on and off in different contexts. The genome is like a recipe book written in DNA that gives instructions on making all the parts of the body. In each organ, only the recipes relevant to that organ should be followed, whether it's the instructions for lung, breast or some other tissue. Like flipping pages in a recipe book, the DNA containing the instructions for turning genes on in the lung is open and used in the lung, for example, but closed and ignored in other types of cells.

Scientists know that some cancer cells are opening the wrong pages in the recipe book—ones that contain the SOX2 gene, which can cause tumours to grow uncontrollably. They wanted to find out: how does the gene become expressed in cancer cells?

The researchers analyzed genome data to look for enhancer DNA that could activate SOX2 in cancer cells. The enhancer they found is open in many different types of patient tumors, meaning this could be a cancer enhancer active in bladder, uterus, breast and lung tumors. Unlike many cancer-causing changes, this enhancer reprogramming mechanism does not arise out of mutation due to DNA damage; it is caused by part of the genome opening when it should be staying closed.

The researchers then determined that the enhancer causes increased cancer cell growth because when they removed the enhancer in lab-grown cells, the cancer cells created fewer new tumour colonies.

Part 1

To figure out why cells have a DNA region that makes cancer worse, the team generated mice without this DNA region, and found these mice do not form a separate passage for air and food in their throat as they develop. Thus, this potentially dangerous cancer-enhancer region is likely in the human genome to regulate airway formation as the human body forms. However, if a developing cancer cell opens this region, it will form a tumor that grows faster and is more dangerous for the patient.

The researchers also found that two proteins known to have a role in the developing airways, FOXA1 and NFIB, are now regulating SOX2 in breast cancer.

The enhancer is activated by the FOXA1 protein and suppressed by the NFIB protein. This means that drugs suppressing FOXA1 or activating NFIB may lead to improved treatments for bladder, uterine, breast and lung cnacer.

Now that scientists know how the SOX2 gene is activated in certain types of cancers, they can look at why this is happening by asking,  "Why did the cancer cells end up on the wrong page of the genome recipe book?"

Luis E Abatti et al, Epigenetic reprogramming of a distal developmental enhancer cluster drives SOX2 overexpression in breast and lung adenocarcinoma, Nucleic Acids Research (2023). DOI: 10.1093/nar/gkad734

Part 2

Self-healing of synthetic diamonds observed at room temperature

A team of chemists, materials scientists and aeronautical engineers, reports evidence of self-healing in a sample of synthetic diamond at room temperature.

In their study, reported in the journal Nature Materials, the group created samples of microwire diamonds, caused them to crack and then used an electron microscope to watch them heal. The editors at Nature have also published a Research briefing in the same journal issue outlining the work.

Ever since scientists discovered that diamonds could be made not only in the lab but also in industrial settings, work has been ongoing to find ways to make them less prone to cracking, which limits their use in a wide variety of applications. Prior research has shown that if diamonds are made using a hierarchical internal structure, they become less prone to cracking—but not enough to allow their use in desired applications. More recently, scientists have discovered that nanotwinned diamond composites (ntDC) have some degree of self-healing. But these observations were made with tests conducted at high pressure and temperatures. In this new effort, the research team wondered if similar types of self-healing might be possible at normal pressure and room temperature. To find out, the researchers created several ntDC nanotwinned samples using onion carbon compressed at very high temperatures. They then set up DSC and ntDC nanobeams using an ion beam technique. After mounting ntDC samples, the nanobeams were used to create cracks in the samples, the results of which were viewed using a scanning electron microscope. To ensure their results were reliable, the team conducted multiple fracture tests.

The research team observed self-healing in the ntDC samples. Testing showed the healed samples had a tensile strength of 34%. In studying the healed samples, the researchers found the presence of sp² and sp³-hybridized carbon atoms on opposite sides of cracks, which they describe as osteoblasts; these allowed for healing as they bonded with one another. The team also conducted simulations of what they observed and found that such interactions triggered C-C re-bonding across gaps, allowing healing.

Keliang Qiu et al, Self-healing of fractured diamond, Nature Materials (2023). DOI: 10.1038/s41563-023-01656-4

Fractured diamond can heal itself at room temperature, Nature Materials (2023). DOI: 10.1038/s41563-023-01665-3

Nobel in medicine goes to two scientists whose work enabled creation of mRNA vaccines against COVID-19

Two scientists won the Nobel prize in medicine on Monday for discoveries that enabled the creation of mRNA vaccines against COVID-19 that were critical in slowing the pandemic—technology that's also being studied to fight cancer and other diseases.

Katalin Karikó and Drew Weissman were cited for contributing "to the unprecedented rate of vaccine development during one of the greatest threats to human health," according to the panel that awarded the prize in Stockholm.

The panel said the pair's "groundbreaking findings ... fundamentally changed our understanding of how mRNA interacts with our immune system."

Traditionally, making vaccines required growing viruses or pieces of viruses and then purifying them before next steps. The messenger RNA approach starts with a snippet of genetic code carrying instructions for making proteins. Pick the right virus protein to target, and the body turns into a mini vaccine factory.

But in early experiments with animals, simply injecting lab-grown mRNA triggered a reaction that usually destroyed it. Karikó and Weissman figured out a tiny modification to the building blocks of RNA that made it stealthy enough to slip past immune defenses.

mRNA   vaccine is a "game changer" in shutting down the coronavirus pandemic, crediting the shots with saving millions of lives.

The duo's pivotal mRNA research was combined with two other earlier scientific discoveries to create the COVID-19 vaccines.

www.nobelprize.org/prizes/medi … dvanced-information/

Separating molecules requires a lot of energy. A nanoporous, heat-resistant membrane could change that

Industry has long relied upon energy-intensive processes, such as distillation and crystallization, to separate molecules that ultimately serve as ingredients in medicine, chemicals and other products.

In recent decades, there has been a push to supplant these processes with membranes, which are potentially a lower-cost and eco-friendly alternative. Unfortunately, most membranes are made from polymers that degrade during use, making them impractical.

To solve this problem, a  research team has created a new, sturdier membrane that can withstand harsh environments—high temperatures, high pressure and complex chemical solvents—associated with industrial separation processes.

Made from an inorganic material called carbon-doped metal oxide, it is described in a study published Sept. 7 in Science.

Researchers have developed is a technique to easily fabricate defect-free, strong membranes that have rigid nanopores that can be precisely controlled to allow different-sized molecules to pass through.

To create the membrane, the research team took inspiration from two common, but unrelated, manufacturing techniques.

The first is molecular layer deposition, which involves layering thin films of materials and is most often associated with semiconductor production. The second technique is interfacial polymerization, which is a method of combining chemicals that is commonly used to create fuel cells, chemical sensors and other electronics.

Bratin Sengupta et al, Carbon-doped metal oxide interfacial nanofilms for ultrafast and precise separation of molecules, Science (2023). DOI: 10.1126/science.adh2404

 Scientists find microplastics  in clouds too!

Researchers  have confirmed microplastics are present in clouds, where they are likely affecting the climate in ways that aren't yet fully understood.

In a study published in Environmental Chemistry Letters, scientists climbed Mount Fuji and Mount Oyama in order to collect water from the mists that shroud their peaks, then applied advanced imaging techniques to the samples to determine their physical and chemical properties.

The team identified nine different types of polymers and one type of rubber in the airborne microplastics—ranging in size from 7.1 to 94.6 micrometers.

Each liter of cloud water contained between 6.7 to 13.9 pieces of the plastics.

What's more, "hydrophilic" or water-loving polymers were abundant, suggesting the particles play a significant role in rapid cloud formation and thus climate systems.

"If the issue of 'plastic air pollution' is not addressed proactively, climate change and ecological risks may become a reality, causing irreversible and serious environmental damage in the future," the researchers warned.

When microplastics reach the upper atmosphere and are exposed to ultraviolet radiation from sunlight, they degrade, contributing to greenhouse gasses.

Microplastics—defined as plastic particles under 5 millimeters—come from industrial effluent, textiles, synthetic car tires,  personal care productsand much more.

Yize Wang et al, Airborne hydrophilic microplastics in cloud water at high altitudes and their role in cloud formation, Environmental Chemistry Letters (2023). DOI: 10.1007/s10311-023-01626-x

The very first beat: How a heart starts to pulse

How muscles change during endurance training

Nobel Prize in physics for split-second glimpse of superfast spinning world of electrons

Three scientists won the Nobel Prize in physics on Tuesday for giving us the first split-second glimpse into the superfast world of spinning electrons, a field that could one day lead to better electronics or disease diagnoses.

The award went to French-Swedish physicist Anne L'Huillier, French scientist Pierre Agostini and Hungarian-born Ferenc Krausz for their work with the tiny part of each atom that races around the center and is fundamental to virtually everything: chemistry, physics, our bodies and our gadgets.

Electrons move so fast that they have been out of reach of human efforts to isolate them, but by looking at the tiniest fraction of a second possible, scientists now have a "blurry" glimpse of them and that opens up whole new sciences. 

The electrons are very fast, and the electrons are really the workforce in everywhere. Once you can control and understand electrons, you have taken a very big step forward.

The scientists, who worked separately, used ever-quicker laser pulses to catch the atomic action that happened at such dizzying speeds—one quintillionth of a second, known as an attosecond.

www.nobelprize.org/uploads/202 … physicsprize2023.pdf

Atmospheric microplastic transport predominantly derived from oceans, study finds

Microplastics in our natural environments are of increasing concern as these tiny particles (<5mm diameter) pollute ecosystems, posing issues to the well-being of animals and humans alike. There are two principal categories of microplastics: primary particles are manufactured for their size and originate from consumer products, such as the microbeads used in cosmetics, while secondary microplastics occur due to the breakdown of larger materials, such as plastic water bottles and matter from industrial waste.

This breakdown occurs due to ultraviolet radiation from the sun causing plastic to become brittle and thus susceptible to the erosive action of waves in particular to shear off flakes into the surrounding environment.

Their longevity during decomposition, taking upwards of 500 years to complete in a landfill, is a critical factor of their detrimental impact on habitats. Marine animals ingest microplastics suspended in the ocean, and microplastics mixed with the sand on our beaches is barely noticeable. Research has discovered microplastics in the smallest plankton all the way through to filter feeding giants of the sea—whales.

But it is not just the ocean that transports these tiny particles across the globe. Atmospheric wind regimes can carry microplastics vast distances, and their shape has a critical impact on airborne retention before deposition.

New research published in Nature Geoscience considers a theory-based model to determine the settling velocity (the point at which a particle stops being suspended in air and settles due to gravity) of microplastics of various sizes and shapes (up to 100μm long and down to 2μm wide), as compared to previous research that has assumed spherical microplastics. The effect of air turbulence on settling velocity was also factored to determine long distance transport.

 Shuolin Xiao et al, Long-distance atmospheric transport of microplastic fibres influenced by their shapes, Nature Geoscience (2023). DOI: 10.1038/s41561-023-01264-6

Science trying to take the STING out of runaway inflammation

Cytokine storm: Everybody came to know about it during the covid-19 pandemic.  But once this dangerous form of infection-triggered runaway inflammation started claiming lives by the thousands, a legion of scientists jumped into the hunt for ways to calm these storms.

Now, a study led by immunobiology experts at Cincinnati Children's, offers important new details on how two elements of our body's immune system clash with each other to prompt a chain of reactions that can release deadly floods of cell-killing, organ-damaging cytokines. Details were published Oct. 3, 2023, in the journal Cell Reports.

These findings have implications for both autoimmunity as well as cancer. Researchers have discovered an independent cell signaling pathway that allows a type of immune cell called an effector memory T cell (T_em) to become a critical driver of innate cytokine storms.

With a pathway defined, next steps include confirming whether medications that target key points along the pathway can disrupt the inflammation cycle before it becomes uncontrollable.

Part 1

The chain reaction appears to start when T_em cells interact with dendritic cells, which serve as the immune system's primary detector of viral and bacterial invasions. These starburst shaped cells carry a large collection of receptors to detect various types of invaders. Once they encounter a harmful visitor, dendritic cells latch on and sound an alarm that instructs the rest of the immune system's machinery to begin producing T cells that are custom designed to eliminate that type of invader.

When the immune system wins the battle, most of the custom T cells stand down. But a few guards linger in the blood and other body tissues to be ready to "effect" a rapid response should the same type on infection occur again. Hence the name effector memory T cells.

However, the research team discovered that ongoing encounters with T_em cells, such as those occurring when people have autoimmunity or live in a state of chronic inflammation, actually cause DNA strands within dendritic cells to break. This, in turn, prompts a DNA repair pathway that rapidly generates large numbers of inflammatory cytokines, including IL-1b, IL-6 and IL-12.

This flood, or storm, of cytokines causes the tissue damage that occurs in autoinflammatory diseases including type 1 diabetes, multiple sclerosis, rheumatoid arthritis, and inflammatory bowel diseases like Crohn's disease. For some people with these conditions, ongoing inflammation also increases their risk of developing cancer.

Scientists worked for the last 10 years to examine the genetic activity and cell-to-cell communications occurring behind this process. 

The team found a surprising clue when examining the transcriptional profile of dendritic cells following their interaction with T_em cells. Specifically, they detected upregulation of expression of Tmem173, which encodes for stimulator of interferon genes (STING). The STING pathway has been described in previous research as being important to detect viral infections. But when T_em cells harm dendritic cells, the STING pathway does not follow the same route that it typically does when directly responding to viral infections.

In this situation, STING teams up with the gene TRAF6 and the transcription factor NFkB to form an "axis" of activity that drives runaway production of innate inflammatory cytokines.

The researchers further reasoned that if they could prevent STING and TRAF6 from working together, they could cut off the inflammation chain reaction at an early stage. In mice gene-edited to lack the STING pathway, that's exactly what they found. When treated with a drug known to induce an intense T cell-mediated inflammatory response, these mice did not produce a flood of innate cytokines.

The mouse study involved a whole-body elimination of STING. Attempting the same in humans would not be advisable because STING is used by a number of cell types outside the immune system in necessary ways.

Part 2

The goal before the scientists now is  to develop a highly focused method or methods for blocking STING within targeted immune cells, without disrupting its other important functions. If they  can achieve that, they may have a powerful new tool for controlling hyper-inflammation.

Hannah Meibers et al, Effector Memory T cells induce innate inflammation by triggering DNA damage and a non-canonical STING pathway in dendritic cells, Cell Reports (2023). DOI: 10.1016/j.celrep.2023.113180. www.cell.com/cell-reports/full … 2211-1247(23)01192-0

Part 3

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Why does it get hot when you rub things together? Unraveling the mystery of dynamic friction at the atomic level

Friction, an everyday phenomenon, has perplexed scientists for centuries. Though extensively researched, our understanding remains fragmented, primarily due to the multifaceted interactions that span across varying scales. Achieving an accurate grasp of the precise contact conditions between objects has been a longstanding challenge, a feat recently made possible through advancements in scanning probe microscopy.

Yet, even with these technological breakthroughs, the intricacies of dynamic friction—the force needed to maintain the movement of a molecule—have remained elusive. While scientists can measure static friction by moving a single molecule on a surface, both the measurement and theoretical understanding of dynamic friction have yet to be fully unveiled. Now, writing in Physical Review Letters and Physical Review B, a collaborative team of scientists report their groundbreaking study that dives deep into this challenge. They meticulously examined the manipulation of a carbon monoxide (CO) molecule on a single-crystal copper surface using an atomic force microscope. Backed by ab initio calculations, their findings shed light on how the CO molecule positions change relative to the microscope tip and surface, as well as the relationship between the motion of the molecule induced by the tip, energy dissipation, and both static and dynamic friction. This research stands out for its unequivocal clarity on the friction process. Not only does it provide fresh insights into a long-studied phenomenon, but it also paves the way for future studies on energy dissipation relaxation processes.

Norio Okabayashi et al, Dynamic Friction Unraveled by Observing an Unexpected Intermediate State in Controlled Molecular Manipulation, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.148001

Norio Okabayashi et al, Energy dissipation of a carbon monoxide molecule manipulated using a metallic tip on copper surfaces, Physical Review B (2023). DOI: 10.1103/PhysRevB.108.165401

**

Research shows humans can inherit AI biases

New research by psychologists provides evidence that people can inherit artificial intelligence biases (systematic errors in AI outputs) in their decisions.

The astonishing results achieved by AI systems that can, for example, hold a conversation as a human does have given this technology an image of high reliability.

More and more professional fields are implementing AI-based tools to support the decision-making of specialists to minimize errors in their decisions. However, this technology is not without risks due to biases in AI results. We must consider that the data used to train AI models reflects past human decisions. If this data hides patterns of systematic errors, the AI algorithm will learn and reproduce these errors. Indeed, extensive evidence indicates that AI systems do inherit and amplify human biases.

The most relevant finding of this new research is that the opposite effect may also occur: that humans inherit AI biases. That is, not only would AI inherit its biases from human data, but people could also inherit those biases from AI, with the risk of getting trapped in a dangerous loop. 

The most significant finding of the research was that after interaction with the AI system, those volunteers continued to mimic its systematic error when they switched to performing the diagnosis task unaided. In other words, participants who were first assisted by the biased AI replicated its bias in a context without this support, thus showing an inherited bias. This effect was not observed for the participants in the control group, who performed the task unaided from the beginning.

These results show that biased information by an artificial intelligence model can have a perdurable negative impact on human decisions. The finding of an inheritance of AI bias effect points to the need for further psychological and multidisciplinary research on AI-human interaction.

Furthermore, evidence-based regulation is also needed to guarantee fair and ethical AI, considering not only the AI technical features but also the psychological aspects of the AI and human collaboration.

Lucía Vicente et al, Humans inherit artificial intelligence biases, Scientific Reports (2023). DOI: 10.1038/s41598-023-42384-8

When fire & ice combine

Nobel Prize in chemistry for work on quantum dots, used in electronics and medical imaging

Three scientists won the Nobel Prize in chemistry Wednesday for their work on quantum dots—tiny particles just a few nanometers in diameter that can release very bright colored light and whose applications in everyday life include electronics and medical imaging.

Moungi Bawendi of MIT, Louis Brus of Columbia University, and Alexei Ekimov of Nanocrystals Technology Inc., were honored for their work with the tiny particles that "have unique properties and now spread their light from television screens and LED lamps," according to the Royal Swedish Academy of Sciences, which announced the award in Stockholm.

Quantum dots are tiny inorganic particles that glow a range of colors from red to blue when exposed to light. The color they emit depends upon the size of the particle.

Scientists can engineer the dots from materials that include gold to graphene to cadmium, and create their color by controlling their size. The tiniest particles, in which electrons are most tightly confined, emit blue light. Slightly larger particles, in which electrons bounce around a longer wavelength, emit red light.

What is anaphylaxis?

Maybe volcanoes doomed the dinosaurs

A machine-learning algorithm suggests that volcanic activity, rather than an asteroid,.... The algorithm simulated 300,000 scenarios of different amounts of volcanic gases until it found one that matched data from fossils. The gases would have started to cause dinosaur-dooming climate chaos long before the asteroid impact. “You can actually recreate the environmental conditions that could cause a dinosaur extinction solely by volcanism, as if the asteroid weren’t there,” says computational geologist and study co-author Alexander Cox. “But of course, we can't discount the fact that the asteroid definitely didn't cheer up the dinosaurs.”

https://www.science.org/doi/10.1126/science.adh3875

 How Amazonian forest degradation and monsoon circulation are interlinked

A pair of concerned researchers, has developed a computer model that shows linkages between forest degradation in the Amazon River basin and monsoon circulation.

That research suggested that if deforestation continues in the Amazon River basin, it could lead to a tipping point at which a certain degree of change can cause permanent changes to an ecosystem. In the case of the Amazon, the change would be from rainforest to a drier, savanna-like climate.

Over the course of many years, many studies have been conducted to understand how the characteristics of the Amazon River basin work together to maintain such a large rainforest. Such studies have shown that regional water cycling along with moisture exaltation from the plants, together with sunlight and even dust blown over from Africa, all contribute to the unique ecosystem, the largest rainforest in the world. Such work has also suggested that disruptions to parts of the system, such as cutting down trees, could result in major changes to the ecosystem. And if such changes were to occur, other studies have suggested the region would change from a rainforest to one that featured a vast savanna-like climate. Such a possible change is of major concern to climate scientists because the rainforest produces a lot of the Earth's oxygen. Additionally, destruction of the trees would result in the release of carbon they sequester, likely into the atmosphere, contributing further to climate change.

In this new effort, the researchers attempted to create a model that ties together degradation of the rainforest and monsoon circulation to show how and why a tipping point might be reached. To create their nonlinear dynamical model, the pair used data from other models that have been built over the past 40 years to simulate conditions in the rainforest. They also added weather data for the same period, including rainfall amounts, wind speeds and direction, and degree of evapotranspiration. They then modeled the rainforest in its original state to serve as a starting point. Next, they tweaked parameters to see the effects on the entire system. The model showed that cutting down trees at current rates in the Amazon region would indeed lead to a tipping point. They conclude that ecosystems with a feedback loop, such as the Amazon River basin, are particularly sensitive to change.

Nils Bochow et al, The South American monsoon approaches a critical transition in response to deforestation, Science Advances (2023). DOI: 10.1126/sciadv.add9973

New research may make future design of nanotechnology safer with fewer side effects

A new study, published in Nature Nanotechnology, may offer a strategy that mitigates negative side effects associated with intravenous injection of nanoparticles commonly used in medicine.

Nanotechnology's main advantage over conventional medical treatments is its ability to more precisely target tissues, such as cancer cells targeted by chemotherapy. However, when nanoparticles are injected, they can activate part of the immune system called complement. 

Complement is a group of proteins in the immune system that recognize and neutralize bacteria and viruses, including nanoparticles which are foreign to the body. As a result, nanoparticles are attacked by immune cells triggering side effects that include shortness of breath, elevated heart rate, fever, hypotension, and, in rare cases, anaphylactic shock.

The activation of the immune system after injection of nanoparticles can be challenging to understand and prevent. This new research is one step closer to providing a better understanding and a solution for people to receive the benefits of nanoparticles without side effects.

The researchers say while some progress has been made in mitigating adverse reactions through slow infusion and premedication with steroids and antihistamines, a significant number of people still experience reactions.

The goal is to prevent, avoid and mitigate adverse reactions and immune activation. 

Part 1

Specifically, this study focuses on an interesting group of complement inhibitors (called "regulators"). The research showed promising results.

Researchers  observed that the regulators being studied effectively inhibited complement activation by nanoparticles in human serum in vitro and animal models. Specifically, when injected at very low doses, the regulators completely and safely blocked activation of complement by nanoparticles in the animal models used. According to the authors, this is significant because when nanoparticles activate complement, the resulting immune response can not only cause an adverse reaction but it can also reduce the efficacy of nanomedicines.

This research also provides a better understanding of why and how complement regulators could help the body respond more favorably to nanoparticles. The study team observed that of the trillions of nanoparticles entering the blood in a standard injection, only a small fraction activated complement. Complement regulators worked as soon as nanoparticles started activating complement, thereby promptly mitigating immune activation.

These results suggest we have an exciting opportunity to explore how to further optimize the use of regulators with nanoparticles, with the goal of improving the efficacy and tolerability of multiple nanotechnology-based therapeutics and vaccines.

 The next step is to test the complement inhibitors with multiple nano particles and in difference disease models to fully understand the potential of this approach with the ultimate goal to apply the research in a clinical setting.

Inhibition of Acute Complement Responses Toward Bolus-Injected Nanoparticles by Targeted, Short-Circulating Regulatory Proteins, Nature Nanotechnology (2023). DOI: 10.1038/s41565-023-01514-z. www.nature.com/articles/s41565-023-01514-z

Part 2

**

Iron atoms discovered on the move in Earth's solid inner core

The iron atoms that make up the Earth's solid inner core are tightly jammed together by astronomically high pressures—the highest on the planet.

But even here, there's space for wiggle room, researchers have found.

A study led by The University of Texas at Austin and collaborators in China found that certain groupings of iron atoms in the Earth's inner core are able to move about rapidly, changing their places in a split second while maintaining the underlying metallic structure of the iron—a type of movement known as "collective motion" that's akin to dinner guests changing seats at a table.

The results, which were informed by laboratory experiments and theoretical models, indicate that atoms in the inner core move around much more than previously thought.

The results could help explain numerous intriguing properties of the inner core that have long vexed scientists, as well as help shed light on the role the inner core plays in powering Earth's geodynamo—the elusive process that generates the planet's magnetic field.

Scientists think that iron atoms in the inner core are arranged in a repeating hexagonal configuration. According to Lin, most computer models portraying the lattice dynamics of iron in the inner core show only a small number of atoms—usually fewer than a hundred. But using an AI algorithm, the researchers were able to significantly beef up the atomic environment, creating a "supercell" of about 30,000 atoms to more reliably predict iron's properties.

At this supercell scale, the scientists observed groups of atoms moving about, changing places while still maintaining the overall hexagonal structure.

The researchers said that the atomic movement could explain why seismic measurements of the inner core show an environment that's much softer and malleable than would be expected at such pressures.

Youjun Zhang et al, Collective motion in hcp-Fe at Earth's inner core conditions, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2309952120

Scientists discover arginine drives metabolic reprogramming to promote tumor growth in liver cancer

Cancer cells are chameleons. They completely change their metabolism to grow continuously. University of Basel scientists have discovered that high levels of the amino acid arginine drive metabolic reprogramming to promote tumor growth. This study suggests new avenues to improve liver cancer treatment.

The liver is a vital organ with many important functions in the body. It metabolizes nutrients, stores energy, regulates the blood sugar level, and plays a crucial role in detoxifying and removing harmful components and drugs. Liver cancer is one of the world's most lethal types of cancer. Conditions that cause liver cancer include obesity, excessive alcohol consumption and hepatitis C infection. Early diagnosis and appropriate therapeutic strategies are crucial for improving treatments in liver cancer.

In the past decade, scientists have made much progress in understanding the multiple facets of cancer. Historically, it has long been viewed as a disorder in cell proliferation. However, there is growing evidence that cancer is a metabolic disease. In other words, cancer arises when cells rewire their metabolism to allow uncontrolled cell proliferation. How do cells change their metabolism and how does this change in turn lead to tumorigenicity? With their new study in Cell, researchers have discovered a key driver of metabolic rewiring in liver cancer cells.

Healthy liver cells gradually change their behavior when turning into cancer cells. They reprogram their metabolism to grow as fast as possible, for example, they consume much more glucose than normal cells and they enhance the uptake of nutrients.

The most important thing they found is  elevated levels of arginine, although cancer cells produce less or none of this amino acid. The tumour cells accumulate high levels of arginine by increasing its uptake and suppressing its consumption.

Part 1