Sun Exposure Triggers Hunger in Men but Not Women, Study Suggests

Ultraviolet radiation leads to secretion of an appetite-boosting hormone in male mice, but experts say it’s not yet clear whether the mechanism applies to humans.

Millions more at risk from dangerous summer temperatures if climate goals aren't met

Health-threatening heatwaves will become more intense due to climate change, putting millions more people at risk from dangerous summer temperatures, new research has revealed.

The analysis, released recently by researchers, identifies the areas and communities set to be hardest hit by extreme heat.

Communities most vulnerable to the dangerous health impacts of soaring temperatures are those with a high number of older people and children, those without green space to shelter from the heat, and those where the type of housing, such as high rise buildings and mobile homes, is most susceptible to overheating.

According to experts, hot weather can place particular strain on the heart and lungs, meaning that the majority of serious illness and deaths caused by heat are respiratory and cardiovascular. Older people, those with pre-existing health conditions and young children are especially at risk.

In all scenarios, the communities set to be most affected by global heating are those with below average carbon footprints—those less responsible for the climate crisis.

Global temperatures are already 1.1°C above pre-industrial levels. Under the Paris Agreement, governments have agreed to limit warming to 1.5°C to avoid catastrophic climate change.

According to estimates based on current climate pledges, the world is heading towards 2.4°C of warming, but these commitments are not being met.

https://policy.friendsoftheearth.uk/sites/default/files/documents/2...

Obesity: neither genetics nor social background are very good predictors of your body weight – new research

There’s long been debate about whether genetics or the environment people are raised in is the biggest cause of obesity.

Obesity rates have tripled since the 1980s. This is far faster than our genetics could change, suggesting there’s an important environmental element to obesity.

But we also have studies which show that identical twins tend to be more similar in their body weight than non-identical twins, suggesting there’s a genetic element to weight.

Further complicating this debate is the fact that there’s evidence that the influence of genetics may change as people age. For example, when it comes to intelligence, genes seems to be more powerful predictors of intelligence in adults than in children.

A recent study has shown that this is also true of body weight. Researchers found that the amount of influence your environment or genetics may have on whether a person became obese changed throughout their lifetime.

This study showed that genetics had little link with obesity rates during childhood, but strengthened as people got older (from adolescence to age 69).

A similar pattern was also found when it came to a person’s body weight and social background. It was found that people from disadvantaged backgrounds had higher weight from adolescence onwards. However, there was almost no difference in infancy or childhood.

But, as people got older, we also noticed differences in their weight that couldn’t be explained with genetics or social background. This meant that neither of those factors were good predictors of any particular person’s body weight.

Part 1

It was found that  those with a greater number of obesity-related genes had higher body weight. Those in the top 25% for genetic risk of obesity were 11.2kg heavier at age 63 than those in the bottom 25% of genetic risk. People who were from the most disadvantaged homes in childhood were 7.4kg heavier on average than those from the most advantaged backgrounds by age 63.

While these are large differences in body weight, these results suggest that neither genetics nor social background are good predictors of whether or not a person will become obese. While weight differences increased substantially as participants got older, genetic risk only predicted 10% and social background 4% of these differences.

This shows us that there’s still much about body weight that we can’t explain with genetics or social disadvantage, suggesting other factors also have an important influence on our body weight.

It’s important to note the limitations of this work. Researchers focused on only one generation, and their experiences are very different from other generations.

A person’s genetic risk – and the most common genes linked with body weight. However, some rare genes may have a big effect on a person’s body weight.

https://theconversation.com/obesity-neither-genetics-nor-social-bac...

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Part 2

Watch starfish embryos become living crystals!

Watch this shape-shifting magnetic material catch a ball on command

Bacteria-based biohybrid microrobots on a mission to one day battle cancer

A team of scientists in the Physical Intelligence Department at the Max Planck Institute for Intelligent Systems have combined robotics with biology by equipping E. coli bacteria with artificial components to construct biohybrid microrobots. First, as can be seen in Figure 1, the team attached several nanoliposomes to each bacterium. On their outer circle, these spherical-shaped carriers enclose a material (ICG, green particles) that melts when illuminated by near infrared light. Further towards the middle, inside the aqueous core, the liposomes encapsulate water soluble chemotherapeutic drug molecules (DOX).

The second component the researchers attached to the bacterium is magnetic nano particles. When exposed to a magnetic field, the iron oxide particles serve as an on-top booster to this already highly motile microorganism. In this way, it is easier to control the swimming of bacteria—an improved design toward an in vivo application. Meanwhile, the rope binding the liposomes and magnetic particles to the bacterium is a very stable and hard to break streptavidin and biotin complex, which was developed a few years prior and reported in a Nature article, and comes in useful when constructing biohybrid microrobots.

E. coli bacteria are fast and versatile swimmers that can navigate through material ranging from liquids to highly viscous tissues. But that is not all, they also have highly advanced sensing capabilities. Bacteria are drawn to chemical gradients such as low oxygen levels or high acidity—both prevalent near tumor tissue. Treating cancer by injecting bacteria in proximity is known as bacteria mediated tumor therapy. The microorganisms flow to where the tumor is located, grow there and in this way activate the immune system of patients. Bacteria mediated tumor therapy has been a therapeutic approach for more than a century.

For the past few decades, scientists have looked for ways to increase the superpowers of this microorganism even further. They equipped bacteria with extra components to help fight the battle. However, adding artificial components is no easy task. Complex chemical reactions are at play, and the density rate of particles loaded onto the bacteria matters to avoid dilution. The team in Stuttgart has now raised the bar quite high. They managed to equip 86 out of 100 bacteria with both liposomes and magnetic particles.

The scientists showed how they succeeded in externally steering such a high-density solution through different courses.

Once the microrobots are accumulated at the desired point (the tumor spheroid), a near infrared laser generates rays with temperatures of up to 55 degrees Celsius, triggering a melting process of the liposome and a release of the enclosed drugs. A low pH level or acidic environment also causes the nanoliposomes to break open—hence the drugs are released near a tumor automatically.

Bacteria-based biohybrid microrobots with medical functionalities could one day battle cancer more effectively. It is a new therapeutic approach not too far away.

Mukrime Birgul Akolpoglu et al, Magnetically steerable bacterial microrobots moving in 3D biological matrices for stimuli-responsive cargo delivery, Science Advances (2022). DOI: 10.1126/sciadv.abo6163. www.science.org/doi/10.1126/sciadv.abo6163

Whole blood exchange could offer disease-modifying therapy for Alzheimer's disease, study finds

A novel, disease-modifying therapy for Alzheimer's disease may involve the whole exchange of blood, which effectively decreased the formation of amyloid plaque in the brains of mice, according to a new study.

A research team performed a series of whole blood exchange treatments to partially replace blood from mice exhibiting Alzheimer's disease-causing amyloid precursor proteins with complete blood from healthy mice of the same genetic background. The results of the study were published today in Molecular Psychiatry.

This article provides a proof-of-concept for the utilization of technologies commonly used in medical practice, such as plasmapheresis or blood dialysis, to 'clean' blood from Alzheimer's patients, reducing the buildup of toxic substances in the brain. This approach has the advantage that the disease can be treated in the circulation instead of in the brain.

Previous studies  have shown that the misfolding, aggregation, and buildup of amyloid beta proteins in the brain plays a central role in Alzheimer's disease. Therefore, preventing and removing misfolded protein aggregates is considered a promising treatment for the disease.

However, the treatment of Alzheimer's disease has long been complicated, due to the difficulty in delivering therapeutic agents across the blood-brain barrier. In this latest research, scientists have  discovered that manipulating circulating components in Alzheimer's disease could be the key to solving this issue.

After multiple blood transfusions, the researchers found that the development of cerebral amyloid plaques in a transgenic mice model of Alzheimer's disease was reduced by 40% to 80%. This reduction also resulted in improved spatial memory performance in aged mice with the amyloid pathology, and lowered the rates of plaque growth over time.

While the exact mechanism by which this blood exchange reduces amyloid pathology and improves memory is currently unknown, there are multiple possibilities. One possible explanation is that lowering amyloid beta proteins in the bloodstream may help facilitate the redistribution of the peptide from the brain to the periphery. Another theory is that blood exchange somehow prevents amyloid beta influx, or inhibits the re-uptake of cleared amyloid beta, among other potential explanations.

However, regardless of the mechanisms of action associated with the blood exchange treatment, the study shows that a target for Alzheimer's disease therapy may lie in the periphery.

 Preventive and therapeutic reduction of amyloid deposition and behavioral impairments in a mice model of Alzheimer's disease by whole blood exchange, Molecular Psychiatry (2022). DOI: 10.1038/s41380-022-01679-4

Smart thermostats inadvertently strain electric power grids

Smart thermostats – those inconspicuous wall devices that help homeowners govern electricity usage and save energy – may be falling into a dumb trap.

Set by default to turn on before dawn, the smart thermostats unintentionally work in concert with other thermostats throughout neighborhoods and regions to prompting inadvertent, widespread energy-demand spikes on the grid.

The smart thermostats are saving homeowners money, but they are also initiating peak demand throughout the network at a bad time of day, according to  engineers in a forthcoming paper in Applied Energy (September 2022.)

https://news.cornell.edu/stories/2022/07/smart-thermostats-inadvert...

https://www.sciencedirect.com/science/article/abs/pii/S030626192200...

Two different white blood cell types play opposing roles in affecting heartbeat irregularities after heart attack

Patients with heart disease are at risk of experiencing a potentially lethal "electrical storm" involving recurrent episodes of a type of irregular heartbeat called ventricular tachycardia (VT).

Electric shock therapy is used to treat VT following a heart attack, but unfortunately, options to prevent VT recurrence are limited.

New research led by investigators at Massachusetts General Hospital reveals that two different white blood cell types influence VT in the heart, suggesting that treatments that influence these cells may help reduce patients' risk of sudden cardiac death.

The work, which is published in Nature Cardiovascular Research, is based on the knowledge that cardiac conditions (such as heart attacks) that increase the risk of VT and other heartbeat irregularities lead to massive changes in the white blood cell populations surrounding the heart.

To study the mechanisms involved, MGH scientists developed a new research model. "It was believed that mice don't get VT after a heart attack, but we discovered a surprisingly simple trick to induce it—feeding mice food with low potassium levels," says senior author Matthias Nahrendorf, MD, Ph.D., an investigator in MGH's Center for Systems Biology, Professor of Radiology at Harvard Medical School, and the Richard Moerschner Endowed MGH Research Institute Chair in Men's Health

"This is a major step forward because now we can study how different white blood cell subclasses influence heart rhythms. It is also clinically relevant because every fifth patient who experiences a heart attack has low blood potassium levels, and these patients are known to be particularly likely to develop heartbeat irregularities, or arrhythmia."

The team's experiments demonstrated that among the different white blood cell types, neutrophils promote VT while macrophages protect against it. "Inflammatory neutrophils give rise to arrhythmia by compromising the electrical function of heart muscle cells called cardiomyocytes," explains Nahrendorf.

"Macrophages, which take up debris, are protective, and deleting them gave rise to electrical storm in mice with low potassium levels who experienced a heart attack. Indeed, these mice were more likely to die from arrhythmia."

The findings indicate that additional research into the roles of white blood cells in arrhythmia could lead to new targeted therapies for irregular heart rhythms.

https://researchnews.cc/news/14300/Two-different-white-blood-cell-t...

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One coronavirus infection wards off another

Data from Qatar suggest that natural immunity induced by infection with SARS-CoV-2 provides a strong shield against reinfection by a pre-Omicron variant for 16 months or longer. This protection against catching the virus dwindles over time, but immunity triggered by previous infection also thwarts the developme... — and this safeguard shows no signs of waning. Scientists also warn that the study’s results do not mean that infected people can skip vaccination. A separate study by many of the same authors found that people who had both natural immunity and vaccine immunity were substantially more protected against the virus than people who had only one of the two.

Reference: medRxiv preprint (not peer reviewed) & The New England Journal of Medicine paper

Woodpeckers don’t have shock absorbers

Woodpeckers regularly smack their heads into trees at a rate of 20 times per second, seemingly without doing damage to their brains. Researchers have long thought the birds were somehow cushioning these blows to their brains with a spongy skull bone or elongated tongue. But researchers analysed high-speed footage of six woodpeckers and found that their heads moved just as fast as their beaks, and simulations found that they probably didn’t use shock absorption because it would require them to bang their heads harder. The study suggests that woodpeckers instead avoid concussions because of their brain’s small size and positioning.

Reference: Current Biology paper

What is the difference between reproducibility and replicability?

 “Reproducibility” refers to instances in which the original researcher's data and computer codes are used to regenerate the results, while “replicability” refers to instances in which a researcher collects new data to arrive at the same scientific findings as a previous study.

Study: Sentences have their own connection in the brain

A new study finds that incoming speech sounds are connected by our brain to our knowledge of grammar, which is quite abstract in nature. But the big question is how does the brain process complex grammatical structures?

A group of researchers from the Max Planck Institute of Psycholinguistics and Radboud University in Nijmegen discovered that the brain encodes the structure of sentences (‘the vase is red’) and phrases (‘the red vase’) into various neural firing patterns.

The findings of the neuroimaging study were published in the PLOS Biology.

How does the brain represent sentences? This is one of the fundamental questions in neuroscience, because sentences are an example of abstract structural knowledge that is not directly observable from speech. While all sentences are made up of smaller building blocks, such as words and phrases, not all combinations of words or phrases lead to sentences.

In fact, listeners need more than just knowledge of which words occur together: they need abstract knowledge of language structure to understand a sentence. So how does the brain encode the structural relationships that make up a sentence?

The researchers created sets of spoken Dutch phrases (such as de rode vaas ‘the red vase’) and sentences (such as de vaas is rood ‘the vase is red’), which were identical in duration and number of syllables, and highly similar in meaning. They also created pictures with objects (such as a vase) in five different colours. Fifteen adult native speakers of Dutch participated in the experiment.

For each spoken stimulus, they were asked to perform one of three tasks in random order. The first task was structure-related, as participants had to decide whether they had heard a phrase or a sentence by pushing a button. The second and third task were meaning-related, as participants had to decide whether the colour or object of the spoken stimulus matched the picture that followed.

As expected from computational simulations, the activation patterns of neurons in the brain were different for phrases and sentences, in terms of both timing and strength of neural connections. These findings show how the brain separates speech into linguistic structure by using the timing and connectivity of neural firing patterns. These signals from the brain provide a novel basis for future research on how our brains create language.

https://theprint.in/science/study-sentences-have-their-own-connecti...

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A tear-soluble contact lens with silicon nanoneedles to treat eye diseases

a team of researchers  has developed a type of contact lens with embedded nanoneedles for treating eye diseases. In their paper published in the journal Science Advances, the group describes how they made their contact lens and how well it worked when tested on rabbits.

Current methods of delivering medications to the eye involve therapies that are applied directly to the outer eye or are injected into it. Neither method is optimal—applied medicines do not penetrate deep enough into the eye and injected medicines are painful and often lead to inflammation. In this new effort, the researchers have come up with a new approach—application of a nanoneedle infused contact lens.

The researchers began with the notion of imbedding nanoneedles into the eye that degrade over time, releasing medication—and the nanoneedles would be so small that they would not cause pain or discomfort. To get the nanoneedles into the eye, they would attach them to a contact lens that would dissolve soon after application to the eye.

The researchers began with the nanoneedles—they grew them using a silicon base, which ensured they would take a long time to dissolve in the eye. They also made them very small—10 times smaller than any that had been tried before. They also developed a unique way to make them, it involved growing the nanoneedles from a silicon and medication mix, then applying a polymer layer to crack them where they joined the silicon base. This involved coating the tiny needles with polymethyl methacrylate. Then the polymer was peeled off the wafer base. The researchers next coated the base of the nanoneedles with another polymer and then removed the first layer. That left the needles embedded in the second polymer material. Once the design was confirmed, the researchers repeated the process in a way that resulted in the base being formed into a contact-lens shape. The final step involved adding a second medication to the lens—one that would be applied to the eye all-at-once as the base dissolved.

The researchers tested their product on rabbit-models and found an almost complete reduction in corneal neovascularization after just 28 days. The group notes that much more work will need to be done before their nanoneedle-based therapy could be used to treat human patients. It will first have to be tested both for efficacy and safety, and also a means for storing the lens once created will need to be developed.

Woohyun Park et al, Biodegradable silicon nanoneedles for ocular drug delivery, Science Advances (2022). DOI: 10.1126/sciadv.abn1772

How blood vessels remember a stroke

The vascular system within our body provides a constant flow of nutrients, hormones and other resources, thus ensuring efficient transport. Researchers now  investigated in which way such a network is able to adapt and change over time. Using computer simulations, they modeled the network and identified adaptation rules for its connections.

They found that the strength of a connection within a network depends on the local flow. This means that links with a low flow below a certain threshold will decay more and more until they eventually vanish.

 As the amount of biological material to build the vascular system is limited and should be used in an efficient way, this mechanism offers an elegant way to streamline the vascular system.

Changes in the network are persistent

Once a connection has become very weak due to a low flow rate, it is very difficult to recover that connection. A common example for this is the blockage of a blood vessel, which in a bad case even might lead to a stroke. During a stroke, some blood vessels in a certain brain region become very weak due of the blockage of blood flow.

The researchers found that in such a case, adaptations in the network are permanent and are maintained after the obstacle is removed. One can say that the network prefers to reroute the flow through existing stronger connections instead of re-growing weaker connections—even if the flow would require the opposite.

With this new understanding of network memory, the researchers can now explain that blood flow permanently changes even after successful removal of the clot. 

Komal Bhattacharyya et al, Memory Formation in Adaptive Networks, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.028101

SPACE TRASH! ft. Chemistry

Chemists Just Rearranged Atomic Bonds in a Single Molecule For The First Time

Chemical engineering has taken a step forward, with researchers from the University of Santiago de Compostela in Spain, the University of Regensburg in Germany, and IBM Research Europe forcing a single molecule to undergo a series of transformations with a tiny nudge of voltage.

Ordinarily, chemists gain precision over reactions by tweaking parameters such as the pH, adding or removing available proton donors to manage the way molecules might share or swap electrons to form their bonds.

"By these means, however, the reaction conditions are altered to such a degree that the basic mechanisms governing selectivity often remain elusive," the researchers note in their report, published in the journal Science.

In other words, the complexity of forces at work pushing and pulling across a large organic molecule can make it hard to get a precise measure on what's occurring at each and every bond.

The team started with a substance called 5,6,11,12-tetrachlorotetracene (with the formula C18H8Cl4) – a carbon-based molecule that looks like a row of four honeycomb cells flanked by four chlorine atoms hovering around like hungry bees.

Sticking a thin layer of the material to a cold, salt-crusted piece of copper, the researchers drove the chlorine-bees away, leaving a handful of excitable carbon atoms holding onto unpaired electrons in a range of related structures.

Two of those electrons in some of the structures happily reconnected with each other, reconfiguring the molecule's general honeycomb shape. The second pair were also keen to pair up not just with each other, but with any other available electron that might buzz their way.

Ordinarily, this wobbly structure would be short-lived as the remaining electrons married up with each other as well. But the researchers found this particular system wasn't an ordinary one.

With a gentle push of voltage from an atom-sized cattle prod, they showed they could force a single molecule to connect that second pair of electrons in such a fashion that the four cells were pulled out of alignment in what's known as a bent alkyne.

Shaken a little less vigorously, those electrons paired up differently, distorting the structure in a completely different fashion into what's known as a cyclobutadiene ring.

Each product was then reformed back into the original state with a pulse of electrons, ready to flip again at a moment's prompting.

By forcing a single molecule to contort into different shapes, or isomers, using precise voltages and currents, the researchers could gain insight into the behaviors of its electrons and the stability and preferable configurations of organic compounds.

From there it could be possible to whittle down the search for catalysts that could push a large-scale reaction of countless molecules in one direction, making the reaction more specific.

https://www.science.org/doi/10.1126/science.abo6471

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Scientifically proven tips on how to keep cool in the heat

If you're unable to take up residence inside air-conditioned buildings here are a few tips, backed by science, that can help you to stay cool.

1) Shed a few layers

Our bodies have cooling all sussed out. When we get hot, we sweat, and as that sweat evaporates it draws heat energy from the skin, cooling us down in the process. So the best way to stay cool if you're out of direct sunlight (and in sympathetic company) is to wear as little as possible.

If you do need to cover up, however, wear loose-fitting clothes that allow air to flow over the skin, speeding up evaporation. Also try to wear light-coloured garments, as these absorb less of the Sun's radiation than darker clothing.

If you're exercising, meanwhile, don some high-tech sportswear that uses 'moisture-wicking' fabrics. These fabrics transport sweat away from the skin to the outer layers of the material, where it can spread out and evaporate away.

2) Have a drink...

As you sweat, you'll need to replace all that water you're losing. One way to figure out how hydrated you are is to check the colour of your urine. If it's light like lemonade, then you're probably fine; if it's dark like apple juice then you're dehydrated.

When you become dehydrated, the body slows down its sweat rate to conserve fluid, making you even hotter. So a drink can rehydrate you and help you cool down.

But while an ice-cold cider may seem like a good idea, alcohol is actually a diuretic (it causes you to pee more), which can make you dehydrated. It also causes the blood vessels in your skin to dilate, making you feel hotter. So if you want to stay cool, go easy on the booze.

3) Don't open all the windows

To create a refreshing breeze on a stifling summer's day, don't haphazardly throw open the windows. Instead, generate a draught by opening downstairs windows that are in the shade, and upstairs windows that are in the Sun.

Because hot air rises, sunny upstairs rooms will be warmer than those that are downstairs in the shade. This sets up a pressure difference, and by strategically opening windows in these rooms you'll create a breeze that draws in cool, fresh air from downstairs and forces warm air out of the house. You can increase this effect by using window-mounted fans to suck in air downstairs and blow out air upstairs.

Scientists develop new method and device to isolate single cells using electric fields

In cancer research, it all comes down to a single cell. Over the last decade, cancer researchers have homed in on the fact that an individual cell from a tumor can be used to perform molecular analyses that reveal important clues about how the cancer developed, how it spreads and how it may be targeted. With this in mind, a team of researchers  has developed an advanced way to isolate single cells from complex tissues. In a study published in Scientific Reports, they show how the approach not only results in high-quality, intact single cells, but is also superior to standard isolation methods in terms of labor, cost and efficiency. The challenge was to develop a technology to enable researchers to more quickly and easily isolate cells from biopsied cancer tissue to ready it for analysis.

In the new process, a tissue biopsy is placed in a liquid-filled receptacle between two parallel plate electrodes. Instead of enzymes, electric field fluctuations are applied to create opposing forces within the liquid. These forces cause the tissue cells to move in one direction and then in the opposite direction, which leads them to cleanly separate, or disassociate from one another.

The new process resulted in dissociation of biopsy tissue in as little as 5 minutes -- three times faster than leading enzymatic and mechanical techniques described  in a previous study. The approach also resulted in "good dissociation of tissues into single cells while preserving cell viability, morphology and cell cycle progression, suggesting utility for sample preparation of tissue specimens for direct single-cell analysis.

According to the researchers, the new approach is, at minimum, 300% more effective than even the most optimized techniques using simultaneous chemical and mechanical dissociation.

E. Celeste Welch, Harry Yu, Gilda Barabino, Nikos Tapinos, Anubhav Tripathi. Electric-field facilitated rapid and efficient dissociation of tissues Into viable single cells. Scientific Reports, 2022; 12 (1) DOI: 10.1038/s41598-022-13068-6

Gas Entrapping Materials to control inflammation

Malarial Host-Parasite Clash Causes Deadly Blood Sugar Drop

Scientists say they have finally figured out why some people with severe malaria end up with dangerous hypoglycemia, also reporting that the condition starves the parasite into changing tactics from virulence to transmission.

Malaria is one of the world's deadliest diseases, responsible for 627,000 deaths worldwide in 2020 alone. In severe cases, patients develop dangerously low blood sugar levels. This complication is especially perilous in children and can be fatal if left untreated, but why it develops in the first place has been a long-standing mystery.

Now, in a study published recently (July 15) in Cell Metabolism, researchers describe the complicated tug-of-war between host and parasite that appears to explain malaria-associated hypoglycemia. According to the study, the host’s blood sugar drops to dangerously low levels as the malaria parasite destroys blood cells. This starves the parasite, which responds by becoming less likely to kill the already-fragile host—but more likely to spread to others.

The researchers explain that both the host and the parasite are demonstrating adaptive behaviors during this process. The host is ridding itself of the parasite by lowering its blood sugar, they say, and the parasite is becoming less virulent to try and keep both itself and the host alive long enough to seed the next generation.  

https://www.cell.com/cell-metabolism/fulltext/S1550-4131(22)00231-5

Strange new phase of matter created in quantum computer acts like it has two time dimensions

By shining a laser pulse sequence inspired by the Fibonacci numbers at atoms inside a quantum computer, physicists have created a remarkable, never-before-seen phase of matter. The phase has the benefits of two time dimensions despite there still being only one singular flow of time, the physicists report July 20 in Nature.

This mind-bending property offers a sought-after benefit: Information stored in the phase is far more protected against errors than with alternative setups currently used in quantum computers. As a result, the information can exist without getting garbled for much longer, an important milestone for making quantum computing viable.

The approach's use of an "extra" time dimension "is a completely different way of thinking about phases of matter.

The workhorses of the team's quantum computer are 10 atomic ions of an element called ytterbium. Each ion is individually held and controlled by electric fields produced by an ion trap, and can be manipulated or measured using laser pulses.

Each of those atomic ions serves as what scientists dub a quantum bit, or "qubit." Whereas traditional computers quantify information in bits (each representing a 0 or a 1), the qubits used by quantum computers leverage the strangeness of quantum mechanics to store even more information. Just as Schrödinger's cat is both dead and alive in its box, a qubit can be a 0, a 1 or a mashup—or "superposition"—of both. That extra information density and the way qubits interact with one another promise to allow quantum computers to tackle computational problems far beyond the reach of conventional computers.

Though the findings demonstrate that the new phase of matter can act as long-term quantum information storage, the researchers still need to functionally integrate the phase with the computational side of quantum computing. 

Philipp Dumitrescu, Dynamical topological phase realized in a trapped-ion quantum simulator, Nature (2022). DOI: 10.1038/s41586-022-04853-4. www.nature.com/articles/s41586-022-04853-4

Human eggs remain healthy for decades by putting 'batteries on standby mode'

Immature human egg cells skip a fundamental metabolic reaction thought to be essential for generating energy, according to the findings of a study by researchers at the Center for Genomic Regulation (CRG) published recently in the journal Nature.

By altering their metabolic activity, the cells avoid creating reactive oxygen species, harmful molecules that can accumulate, damage DNA and cause cell death. The findings explain how human egg cells remain dormant in ovaries for up to 50 years without losing their reproductive capacity.

Humans are born with all the supply of egg cells they have in life. As humans are also the longest-lived terrestrial mammal, egg cells have to maintain pristine conditions while avoiding decades of wear-and-tear. This new work shows this problem is solved by skipping a fundamental metabolic reaction that is also the main source of damage for the cell. As a long-term maintenance strategy, its like putting batteries on standby mode. This represents a brand new paradigm never before seen in animal cells.

Human eggs are first formed in the ovaries during fetal development, undergoing different stages of maturation. During the early stages of this process, immature egg cells known as oocytes are put into cellular arrest, remaining dormant for up to 50 years in the ovaries. Like all other eukaryotic cells, oocytes have mitochondria—the batteries of the cell—which they use to generate energy for their needs during this period of dormancy.

Using a combination of live imaging, proteomic and biochemistry techniques, the authors of the study found that mitochondria in both human and Xenopus oocytes use alternative metabolic pathways to generate energy never before seen in other animal cell types.

A complex protein and enzyme known as complex I is the usual "gatekeeper" that initiates the reactions required to generate energy in mitochondria. This protein is fundamental, working in the cells that constitute living organisms ranging from yeast to blue whales. However, the researchers found that complex I is virtually absent in oocytes. 

The findings could also lead to new strategies that help preserve the ovarian reserves of patients undergoing cancer treatment.

 Elvan Böke, Oocytes maintain ROS-free mitochondrial metabolism by suppressing complex I, Nature (2022). DOI: 10.1038/s41586-022-04979-5. www.nature.com/articles/s41586-022-04979-5

With just a tablespoon of blood, researchers aim to transform cancer treatment

Researchers  have developed a new blood test that provides unprecedented insight into a patient's cancer make-up, potentially allowing doctors to better select treatment options that will improve patient outcomes.

The technology was outlined in a study published recently in Nature.

The first-of-its-kind blood test analyzes the DNA that metastatic cancers shed into the bloodstream, known as circulating tumor DNA or ctDNA. By sequencing the entire genome of this ctDNA, the test reveals characteristics that are unique to each patient's cancer, giving physicians new tools to develop more personalized treatment plans.

With only a few drops of blood, we can now uncover critical information about a person's overall disease and how best to manage their cancer. This test has the potential to help clinicians choose better tailored treatment options and to more efficiently detect treatment resistance, allowing clinicians to adjust clinical care as needed.

 Alexander Wyatt, Deep whole-genome ctDNA chronology of treatment-resistant prostate cancer, Nature (2022). DOI: 10.1038/s41586-022-04975-9. www.nature.com/articles/s41586-022-04975-9

Mouse study shows dopamine released in brain in response to hydration

A team of researchers  has found that a certain part of the brain releases dopamine in response to hydration. In their paper published in the journal Nature, the group describes experiments they conducted with thirsty mice.

Prior research has shown that certain parts of the brain release dopamine, a chemical compound, as a means of providing pleasurable feedback to other parts of the brain. It is released during sex, for example, or when a person eats something they like, particularly foods that are sweet or fatty. In this new effort, the researchers have found that another part of the brain releases dopamine—this time when the brain is hydrated.

Noting that many animals have learned to determine which foods contain more water, the researchers wondered if there was a feedback mechanism in the brain prompting them to eat those foods that would provide more water, leading to more hydration in their brains. To find out, they turned to mice.

The experiments involved restricting water in test mice and using technology that allowed them to focus on the ventral tegmental area (VTA) in the brain. In one experiment, thirsty mice were given unlimited access to water for five minutes while the researchers monitored brain waves emanating from the VTA—a means of measuring how much, if any, dopamine was being produced. As expected, dopamine production levels rose as soon as the mice began drinking. But the researchers were then surprised to find that 10 minutes later, the dopamine levels rose again—coinciding with the amount of time it took for the water they had been drinking to reach their brain. The researchers then repeated the experiment but added salt to the water—the second bump in dopamine was much smaller due to the dehydrating impact of the salt.

James C. R. Grove et al, Dopamine subsystems that track internal states, Nature (2022). DOI: 10.1038/s41586-022-04954-0

Nanomembrane system could help diagnose diseases by isolating biomarkers in tears

Going to the doctor might make you want to cry, and according to a new study, doctors could someday put those tears to good use. In ACS Nano, researchers report a nanomembrane system that harvests and purifies tiny blobs called exosomes from tears, allowing researchers to quickly analyze them for disease biomarkers. Dubbed iTEARS, the platform could enable more efficient and less invasive molecular diagnoses for many diseases and conditions, without relying solely on symptoms.

Diagnosing diseases often hinges on assessing a patient's symptoms, which can be unobservable at early stages, or unreliably reported. Identifying molecular clues in samples from patients, such as specific proteins or genes from vesicular structures called exosomes, could improve the accuracy of diagnoses. However, current methods for isolating exosomes from these samples require long, complicated processing steps or large sample volumes. Tears are well-suited for sample collection because the fluid can be collected quickly and non-invasively, though only tiny amounts can be harvested at a time. So,  researchers wondered if a nanomembrane system, which they originally developed for isolating exosomes from urine and plasma, could allow them to quickly obtain these vesicles from tears and then analyze them for disease biomarkers.

The researchers successfully distinguished between healthy controls and patients with various types of dry eye disease based on a proteomic assessment of extracted proteins. Similarly, iTEARS enabled researchers to observe differences in microRNAs between patients with diabetic retinopathy and those that didn't have the eye condition, suggesting that the system could help track disease progression. The team says that this work could lead to a more sensitive, faster and less invasive molecular diagnosis of various diseases—using only tears.

Liang Hu et al, Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS, ACS Nano (2022). DOI: 10.1021/acsnano.2c02531

Nanomembrane system could help diagnose diseases by isolating biomarkers in tears

Going to the doctor might make you want to cry, and according to a new study, doctors could someday put those tears to good use. In ACS Nano, researchers report a nanomembrane system that harvests and purifies tiny blobs called exosomes from tears, allowing researchers to quickly analyze them for disease biomarkers. Dubbed iTEARS, the platform could enable more efficient and less invasive molecular diagnoses for many diseases and conditions, without relying solely on symptoms.

Diagnosing diseases often hinges on assessing a patient's symptoms, which can be unobservable at early stages, or unreliably reported. Identifying molecular clues in samples from patients, such as specific proteins or genes from vesicular structures called exosomes, could improve the accuracy of diagnoses. However, current methods for isolating exosomes from these samples require long, complicated processing steps or large sample volumes. Tears are well-suited for sample collection because the fluid can be collected quickly and non-invasively, though only tiny amounts can be harvested at a time. So, researchers wondered if a nanomembrane system, which they originally developed for isolating exosomes from urine and plasma, could allow them to quickly obtain these vesicles from tears and then analyze them for disease biomarkers.

The team modified their original system to handle the low volume of tears. The new system, called "Incorporated Tear Exosomes Analysis via Rapid-isolation System" (iTEARS), separated out exosomes in just 5 minutes by filtering tear solutions over nanoporous membranes with an oscillating pressure flow to reduce clogging. Proteins from the exosomes could be tagged with fluorescent probes while they were still on the device and then transferred to other instruments for further analysis. Nucleic acids were also extracted from the exosomes and analyzed.

The researchers successfully distinguished between healthy controls and patients with various types of dry eye disease based on a proteomic assessment of extracted proteins. Similarly, iTEARS enabled researchers to observe differences in microRNAs between patients with diabetic retinopathy and those that didn't have the eye condition, suggesting that the system could help track disease progression. The team says that this work could lead to a more sensitive, faster and less invasive molecular diagnosis of various diseases—using only tears.

Liang Hu et al, Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS, ACS Nano (2022). DOI: 10.1021/acsnano.2c02531

Woodpeckers' heads act more like stiff hammers than safety helmets

Scientists had long wondered how woodpeckers can repeatedly pound their beaks against tree trunks without doing damage to their brains. This led to the notion that their skulls must act like shock-absorbing helmets. Now, researchers reporting in the journal Current Biology on July 14 have refuted this notion, saying that their heads act more like stiff hammers. In fact, their calculations show that any shock absorbance would hinder the woodpeckers' pecking abilities.

Sam Van Wassenbergh, Erica J. Ortlieb, Maja Mielke, Christine Böhmer, Robert E. Shadwick, Anick Abourachid. Woodpeckers minimize cranial absorption of shocks. Current Biology, 2022; DOI: 10.1016/j.cub.2022.05.052

Quantum computer works with more than zero and one

Computers work with zeros and ones, also known as binary information. This approach has been so successful that computers now power everything from ATMs to self-driving cars and planes and it is hard to imagine a life without them.

Building on this success, today's quantum computers are also designed with binary information processing in mind. The building blocks of quantum computers, however, are more than just zeros and ones. However, restricting them to binary systems prevents these devices from living up to their true potential.

A research team  now succeeded in developing a quantum computer that can perform arbitrary calculations with so-called quantum digits (qudits), thereby unlocking more computational power with fewer quantum particles. Their study is published in Nature Physics.

Although storing information in zeros and ones is not the most efficient way of doing calculations, it is the simplest way. Simple often also means reliable and robust, so binary information has become the unchallenged standard for classical computers.

In the quantum world, the situation is quite different. In the Innsbruck quantum computer, for example, information is stored in individual trapped Calcium atoms. Each of these atoms naturally has eight different states, of which typically only two are used to store information. Indeed, almost all existing quantum computers have access to more quantum states than they use for computation.

The physicists from Innsbruck have now developed a quantum computer that can make use of the full potential of these atoms, by computing with qudits. Contrary to the classical case, using more states does not make the computer less reliable. Quantum systems naturally have more than just two states and the researchers showed that they can control them all equally well.

Martin Ringbauer, A universal qudit quantum processor with trapped ions, Nature Physics (2022). DOI: 10.1038/s41567-022-01658-0. www.nature.com/articles/s41567-022-01658-0

Horizontal Gene Transfer Happens More Often Than Anyone Thought

DNA passed to and from all kinds of organisms, even across kingdoms, has helped shape the tree of life, to a large and undisputed degree in microbes and also unexpectedly in multicellular fungi, plants, and animals.

https://www.the-scientist.com/features/horizontal-gene-transfer-hap...

SARS-CoV-2 Could Use Nanotubes to Infect the Brain

While the study did show a potential way that neurons could be infected, the researchers didn’t show evidence that ACE2-positive cells could infect the types of epithelial cells that compose the blood-brain barrier. They also didn’t directly show that blood-brain barrier cells could form TNTs and transfer the virus to neurons. “Are blood-brain barrier cells capable of inducing these bridges?” scientists now will have to answer this Q.

Tunneling nanotubes provide a route for SARS-CoV-2 spreading

https://www.science.org/doi/10.1126/sciadv.abo0171

https://www.the-scientist.com/news-opinion/sars-cov-2-could-use-nan...

Part 2

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Engineering team develops process to make implants safer

An interdisciplinary team of researchers have developed a new plasma-enabled process that could limit the proliferation of toxins from implants into a patient's bloodstream. 

In their published paper,  the authors explain that a major challenge of developing nanoparticle-modified biomedical implant material is to stably attach metallic nanoparticles on different surfaces—particularly polymer surfaces.

For years, scientists have achieved synthesis of metallic nanoparticles in aqueous solutions using both chemical and biological (plant extracts) reducing agents. The challenge of attaching metallic nanoparticles is especially difficult in cases involving hydrophobic polymeric biomaterials, which most polymeric biomaterials fall under.

To address this challenge, Thomas and his team developed a plasma-enabled process called plasma electroless reduction. The PER process allows researchers to deposit gold and silver nanostructures on different 2D and 3D polymer material surfaces, such as cellulose paper, polypropylene-based facemasks and 3D printed polymer scaffolds.

It is well known that there are toxicity issues offered by the rapid and premature release of the metallic nanostructures from the implant material into the bloodstream. This issue could be addressed only by ensuring the stable anchoring of the metallic nanostructures on implant surfaces. This has inspired us to optimize our PER process by conducting systematic and in-depth investigation of concentration of the metallic precursor followed by sonication wash before cell culture in vitro.

The team  was able to successfully anchor silver nanoparticles on the surface of 3D printed polymers without any rapid release into the surroundings. The team's additive manufacturing expertise also allowed them to design smaller 3D scaffold wafers that will fit into the well of a 96-well plate.

This systematic optimization of making uniform metal nanostructures on 3D scaffolds with cytocompatibility and potential antibacterial properties will be highly relevant and can potentially make an impact on the future development of biocompatible scaffolds, especially for osteomyelitis disease.

Vineeth M. Vijayan et al, Plasma Electroless Reduction: A Green Process for Designing Metallic Nanostructure Interfaces onto Polymeric Surfaces and 3D Scaffolds, ACS Applied Materials & Interfaces (2022). DOI: 10.1021/acsami.2c01195

How Climate Patterns Thousands of Miles Away Affect US Bird Migration

Scientists blunt the impact of natural killer cells to improve vaccine effectiveness

Scientists have discovered that the body's own natural killer cells can suppress the immune benefits of therapeutic vaccines, a problem that can affect inoculations against chronic viral infections and cancer.

Indeed, the scientific literature is replete with examples of otherwise effective vaccines sometimes proving impotent. Increasingly, the reasons are pointing to an enemy within the body itself: a friend that transforms into a foe.

Scientists have been investigating the conundrum and have turned to an animal model to decipher how natural killer cells inadvertently blunt the benefits of vaccines.

In Science Translational Medicine, researchers report that natural killer cells can react so overwhelmingly after vaccination that they negatively impact a critical constituent of the immune response—CD8+T cells. This vital population can become overworked and exhausted, they found, a phenomenon that causes vaccination to have little effectiveness.

Therapeutic vaccines for chronic infections have reduced efficacy because of the presence of exhausted T cells and [an] environment that limits vaccine response. The problem invariably begins with the aggression of natural killer cells.

Working with a mouse model, scientists have found that a combination treatment can boost robust immune responses after vaccination by acting on natural killer cells. The strategy, the team said, may eventually prove useful in the design and improvement of therapeutic vaccines for chronic viral infections and cancers.

Mariana O. Diniz et al, NK cells limit therapeutic vaccine–induced CD8 + T cell immunity in a PD-L1–dependent manner, Science Translational Medicine (2022). DOI: 10.1126/scitranslmed.abi4670

Researchers identify how cells move faster through mucus than blood

Researchers  have discovered that certain cells move surprisingly faster in thicker fluid—think honey as opposed to water, or mucus as opposed to blood—because their ruffled edges sense the viscosity of their environment and adapt to increase their speed.

Their combined results in cancer and fibroblast cells—the type that often creates scars in tissues—suggest that the viscosity of a cell's surrounding environment is an important contributor to disease, and may help explain tumor progression, scarring in mucus-filled lungs affected by cystic fibrosis, and the wound-healing process.

The study, "Membrane ruffling is a mechanosensor of extracellular fluid viscosity," published today in Nature Physics, sheds new light on cell environments, an under-explored area of research.

The study found that the thicker the surrounding environment, the stronger the cells adhere to the substrate and the faster they move—much like walking on an icy surface with shoes that have spikes, versus shoes with no grip at all.

Jian Liu, Membrane ruffling is a mechanosensor of extracellular fluid viscosity, Nature Physics (2022). DOI: 10.1038/s41567-022-01676-y. www.nature.com/articles/s41567-022-01676-y

Natural clean-up: Bacteria can remove plastic pollution from lakes

A study of 29 European lakes has found that some naturally-occurring lake bacteria grow faster and more efficiently on the remains of plastic bags than on natural matter like leaves and twigs.

The bacteria break down the carbon compounds in plastic to use as food for their growth.

The scientists say that enriching waters with particular species of bacteria could be a natural way to remove plastic pollution from the environment.

The effect is pronounced: the rate of bacterial growth more than doubled when plastic pollution raised the overall carbon level in lake water by just 4%.

The results suggest that the plastic pollution in lakes is 'priming' the bacteria for rapid growth— the bacteria are not only breaking down the plastic but are then more able to break down other natural carbon compounds in the lake.

Lake bacteria were found to favor plastic-derived carbon compounds over natural ones. The researchers think this is because the carbon compounds from plastics are easier for the bacteria to break down and use as food.

The scientists caution that this does not condone ongoing plastic pollution. Some of the compounds within plastics can have toxic effects on the environment, particularly at high concentrations.

Eleanor Sheridan, Plastic pollution fosters more microbial growth in lakes than natural organic matter, Nature Communications (2022). DOI: 10.1038/s41467-022-31691-9. www.nature.com/articles/s41467-022-31691-9

Research breakthrough in mystery child hepatitis

Researchers reported a breakthrough this week in mysterious hepatitis cases affecting young children, finding the serious liver condition was linked to co-infection of two common viruses, but not the coronavirus.

The World Health Organization (WHO) has reported at least 1,010 probable cases, including 46 that required transplants and 22 deaths from the illness dating back to last October.

Previous theories had centered on a spike in commonly found adenovirus infections being behind the cases.

But in two new studies carried out independently and simultaneously in Scotland and London, scientists found another virus, AAV2 (adeno-associated virus 2) played a significant role and was present in 96 percent of all patients examined.

AAV2 is not normally known to cause disease and cannot replicate itself without another "helper" virus being present.

Both teams concluded that co-infection with either AAV2 and an adenovirus, or sometimes the herpes virus HHV6, offered the best explanation for the severe liver disease.

The presence of the AAV2 virus is associated with unexplained hepatitis in children. also cautioned it was not yet certain whether AAV2 was causing the disease or was rather a biomarker for underlying adenovirus infection that is harder to detect but was the main pathogen.

Both papers have been posted online to "preprint" servers and still await peer review before they are published in journals.

https://media.gosh.nhs.uk/documents/MEDRXIV-2022-277963v1-Breuer.pdf

https://www.medrxiv.org/content/10.1101/2022.07.19.22277425v1

https://medicalxpress.com/news/2022-07-breakthrough-mystery-child-h...

FNDs

Scientists discover new 'origins of life' chemical reactions

Four billion years ago, the Earth looked very different than it does today, devoid of life and covered by a vast ocean. Over the course of millions of years, in that primordial soup, life emerged. Researchers have long theorized how molecules came together to spark this transition. Now, scientists have discovered a new set of chemical reactions that use cyanide, ammonia and carbon dioxide—all thought to be common on the early earth—to generate amino acids and nucleic acids, the building blocks of proteins and DNA.

In addition to giving researchers insight into the chemistry of the early earth, the newly discovered chemical reactions are also useful in certain manufacturing processes, such as the generation of custom labeled biomolecules from inexpensive starting materials.

Because the new reaction is relatively similar to what occurs today inside cells—except for being driven by cyanide instead of a protein—it seems more likely to be the source of early life, rather than drastically different reactions, the researchers say. The research also helps bring together two sides of a long-standing debate about the importance of carbon dioxide to early life, concluding that carbon dioxide was key, but only in combination with other molecules.

In the process of studying their chemical soup, the researchers discovered that a byproduct of the same reaction is orotate, a precursor to nucleotides that make up DNA and RNA. This suggests that the same primordial soup under the right conditions, could have given rise to a large number of the molecules that are required for the key elements of life.

 Ramanarayanan Krishnamurthy, Prebiotic synthesis of α-amino acids and orotate from α-ketoacids potentiates transition to extant metabolic pathways, Nature Chemistry (2022). DOI: 10.1038/s41557-022-00999-w. www.nature.com/articles/s41557-022-00999-w

Part 1

Earlier this year, Krishnamurthy's group showed how cyanide can enable the chemical reactions that turn prebiotic molecules and water into basic organic compounds required for life. Unlike previously proposed reactions, this one worked at room temperature and in a wide pH range. The researchers wondered whether, under the same conditions, there was a way to generate amino acids, more complex molecules that compose proteins in all known living cells.

In cells today, amino acids are generated from precursors called α-keto acids using both nitrogen and specialized proteins called enzymes. Researchers have found evidence that α-keto acids likely existed early in Earth's history. However, many have hypothesized that before the advent of cellular life, amino acids must have been generated from completely different precursors, aldehydes, rather than α-keto acids, since enzymes to carry out the conversion did not yet exist. But that idea has led to debate about how and when the switch occurred from aldehydes to α-keto acids as the key ingredient for making amino acids.

After their success using cyanide to drive other chemical reactions, Krishnamurthy and his colleagues suspected that cyanide, even without enzymes, might also help turn α-keto acids into amino acids. Because they knew nitrogen would be required in some form, they added ammonia—a form of nitrogen that would have been present on the early earth. Then, through trial and error, they discovered a third key ingredient: carbon dioxide. With this mixture, they quickly started seeing amino acids form.

If you mix only the keto acid, cyanide and ammonia, it just sits there. As soon as you add carbon dioxide, even trace amounts, the reaction picks up speed.

Part 2

Engineers develop stickers that can see inside the body

Ultrasound imaging is a safe and noninvasive window into the body's workings, providing clinicians with live images of a patient's internal organs. To capture these images, trained technicians manipulate ultrasound wands and probes to direct sound waves into the body. These waves reflect back out to produce high-resolution images of a patient's heart, lungs, and other deep organs.

Currently, ultrasound imaging requires bulky and specialized equipment available only in hospitals and doctor's offices. But a new design by MIT engineers might make the technology as wearable and accessible as buying Band-Aids at the pharmacy.

In a paper appearing recently in Science, the engineers present the design for a new ultrasound sticker—a stamp-sized device that sticks to skin and can provide continuous ultrasound imaging of internal organs for 48 hours.

The researchers applied the stickers to volunteers and showed the devices produced live, high-resolution images of major blood vessels and deeper organs such as the heart, lungs, and stomach. The stickers maintained a strong adhesion and captured changes in underlying organs as volunteers performed various activities, including sitting, standing, jogging, and biking.

The current design requires connecting the stickers to instruments that translate the reflected sound waves into images. The researchers point out that even in their current form, the stickers could have immediate applications: For instance, the devices could be applied to patients in the hospital, similar to heart-monitoring EKG stickers, and could continuously image internal organs without requiring a technician to hold a probe in place for long periods of time.

If the devices can be made to operate wirelessly—a goal the team is currently working toward—the ultrasound stickers could be made into wearable imaging products that patients could take home from a doctor's office or even buy at a pharmacy.

Chonghe Wang et al, Bioadhesive ultrasound for long-term continuous imaging of diverse organs, Science (2022). DOI: 10.1126/science.abo2542. www.science.org/doi/10.1126/science.abo2542

Philip Tan et al, Seeing inside a body in motion, Science (2022). DOI: 10.1126/science.adc8732. www.science.org/doi/10.1126/science.adc8732

Alarm as Earth hits 'Overshoot Day' Thursday: NGOs

Mankind marks a dubious milestone Thursday (yesterday), the day by which humanity has consumed all earth can sustainably produce for this year, with NGOS warning the rest of 2022 will be lived in resource deficit.

The date—dubbed "Earth Overshoot Day"—marks a tipping point when people have used up "all that ecosystems can regenerate in one year", according to the Global Footprint Network and WWF.

From January 1 to July 28, humanity has used as much from nature as the planet can renew in the entire year. That's why this July 28 is Earth Overshoot Day.

The Earth has a lot of stock, so we can deplete Earth for some time but we cannot overuse it for ever. It's like with money; we can spend more than we earn for some time until we're broke."

It would take 1.75 Earths to provide for the world's population in a sustainable way, according to the measure, which was created by researchers in the early 1990s.

Global Footprint Network said Earth Overshoot Day has fallen ever sooner over the last 50 years.

Source: News Agencies

Promising evidence of deuterium forming into a metallic state at high pressure

A trio of researchers at the French Alternative Energies and Atomic Energy Commission has shown promising evidence of deuterium forming into a metallic state at high pressure. In their paper published in the journal Physical Review Letters, researchers describe the process they used to pressurize a deuterium sample and test it for a transition state. Theory suggests that all elements should transition to a metallic state if subjected to strong enough pressure. This is because at some point, their electrons will become delocalized. But modeling, much less demonstrating, such transition points has proven to be difficult. Early research looking for the transition state of hydrogen led to theories that it would reach a metallic state when hydrogen molecules disassociated completely. That led to many efforts to see if such theories were true—sadly, none were successful. Then in 2000, a team at Cornell University calculated that hydrogen should transition at 410 GPa. In 2020, the researchers of the current study used a diamond anvil cell to compress a sample of hydrogen to 425 GPa and used synchrotron infrared absorption and Raman spectroscopy to measure the band gap of the material. They found a sudden drop from 0.6eV to 0.1eV at 80K, comprising promising evidence of hydrogen forming into a metallic state as theorized. A short time later, physicist Alexander Goncharov suggested that transitions should happen more easily under conditions where quantum motion could allow for some atoms to tunnel from one place to another. Noting that deuterium nuclei are heavier than hydrogen, the researchers reasoned that they should be less delocalized than protons and thus should require more pressure to transition. To find out if that was the case, the team reran their 2020 effort, only this time, they used deuterium instead of hydrogen. They found the band gap decreased in ways similar to the hydrogen experiment, but it did so at 460 GPa, possibly confirming the theory. The researchers noted that they also saw nothing that would indicate molecular disassociation had occurred in either experiment.

Paul Loubeyre et al, Compression of D2 to 460 GPa and Isotopic Effects in the Path to Metal Hydrogen, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.035501

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Just add water to activate a disposable paper battery

A water-activated disposable paper battery is presented in a proof-of-principle study in Scientific Reports. The authors suggest that it could be used to power a wide range of low-power, single-use disposable electronics—such as smart labels for tracking objects, environmental sensors and medical diagnostic devices—and minimize their environmental impact. The battery, devised by Gustav Nyström and colleagues, is made of at least one cell measuring one centimeter squared and consisting of three inks printed onto a rectangular strip of paper. Sodium chloride salt is dispersed throughout the strip of paper and one of its shorter ends has been dipped in wax. An ink containing graphite flakes, which acts as the positive end of the battery (cathode), is printed onto one of the flat sides of the paper while an ink containing zinc powder, which acts as the negative end of the battery (anode), is printed onto the reverse side of the paper. Additionally, an ink containing graphite flakes and carbon black is printed on both sides of the paper, on top of the other two inks. This ink connects the positive and negative ends of the battery to two wires, which are located at the wax-dipped end of the paper. When a small amount of water is added, the salts within the paper dissolve and charged ions are released. These ions activate the battery by dispersing through the paper, resulting in zinc in the ink at the negative end of the battery releasing electrons. Attaching the wires to an electrical device closes the circuit so that electrons can be transferred from the negative end—via the graphite and carbon black-containing ink, wires and device—to the positive end (the graphite-containing ink) where they are transferred to oxygen in the surrounding air. These reactions generate an electrical current that can be used to power the device.

Part 1

To demonstrate the ability of their battery to run low-power electronics, the authors combined two cells into one battery and used it to power an alarm clock with a liquid crystal display. Analysis of the performance of a one-cell battery revealed that after two drops of water were added, the battery activated within 20 seconds and, when not connected to an energy-consuming device, reached a stable voltage of 1.2 volts. The voltage of a standard AA alkaline battery is 1.5 volts. After one hour, the one-cell battery's performance decreased significantly due to the paper drying. However, after two more drops of water were added, it maintained a stable operating voltage of 0.5 volts for more than one additional hour.

The authors propose that the biodegradability of paper and zinc could enable their battery to minimize the environmental impact of disposable, low-power electronics. They suggest that the sustainability of the battery can be further increased by minimizing the amount of zinc used within the ink, which also allows the amount of electricity the battery generates to be precisely controlled.

Gustav Nyström, Water activated disposable paper battery, Scientific Reports (2022). DOI: 10.1038/s41598-022-15900-5. www.nature.com/articles/s41598-022-15900-5

Part 2

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Scientists confirm COVID tied to wildlife sales at Chinese market

An international team of researchers has confirmed that live animals sold at the Huanan Seafood Wholesale Market were the likely source of the COVID-19 pandemic that has claimed 6.4 million lives since it began nearly three years ago.

“Rigorously combining all available evidence surrounding the emergence of SARS-CoV-2 clearly demonstrates that the virus jumped at least twice from animals to humans at the Huanan market,” said Dr. Marc Suchard, UCLA Fielding School of Public Health professor of biostatistics. “Identifying multiple transmission events finally puts to rest a single origin from elsewhere.”

Co-led by Suchard and Dr. Michael Worobey (University of Arizona), Dr. Joel Wertheim (UCSD) and Dr. Kristian Andersen (Scripps Research Institute), international teams of researchers have traced the start of the pandemic to the market in Wuhan, China, where foxes, raccoon dogs, and other live mammals susceptible to the virus were sold immediately before the pandemic began. Their findings were published Tuesday in two peer-reviewed papers in the journal Science, after being previously released in pre-print versions in February.

The publications, which have since gone through peer review and include additional analyses and conclusions, virtually eliminate alternative scenarios that have been suggested as origins of the pandemic. Moreover, the authors conclude that the first spread to humans from animals likely occurred in two separate transmission events in the Huanan market in late November 2019.

One study – “The Huanan Seafood Wholesale Market in Wuhan was the early epicenter of the COVID-19 pandemic” - scrutinized the locations of the first known COVID-19 cases, as well as swab samples taken from surfaces at various locations at the market. The other – “The molecular epidemiology of multiple zoonotic origins of SARS-CoV-2” - focused on genomic sequences of SARS-CoV-2 from samples collected from COVID-19 patients during the first weeks of the pandemic in China.

Along with Suchard, a physician who also teaches at the David Geffen School of Medicine at UCLA, UCLA post-doctoral scholars Andrew Magee and Karthik Gangavarapu co-authored this work.

The first paper examined the geographic pattern of COVID-19 cases in the first month of the outbreak, December 2019. The team was able to determine the locations of almost all of the 174 COVID-19 cases identified by the World Health Organization that month, 155 of which were in Wuhan.

Analyses showed that these cases were clustered tightly around the Huanan market, whereas later cases were dispersed widely throughout Wuhan – a city of 11 million people. Notably, the researchers found that a striking percentage of early COVID patients with no known connection to the market – meaning they neither worked there nor shopped there – turned out to live close-by.

Part 1

Fossil-fuel emissions hamper carbon dating

The burning of fossil fuels has officially shifted the composition of carbon isotopes in the air of the Northern Hemisphere enough to cancel out a useful signal from nuclear-weapons testing. This could cause a headache for archaeologists, because modern items now look like objects from the early twentieth century in terms of radiocarbon dating. The development means that forensic scientists will no longer be able to use radiocarbon fingerprints to pinpoint the ages of materials such as ivory, antiques and wine. “If you’re working in forensics or detecting fakes, this is a really sad moment.

Carbon dating hampered by rising fossil-fuel emissions