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Scientists studying leaves from a 23-million-year-old forest have for the first time linked high levels of atmospheric carbon dioxide with increased plant growth, and the hot climate off the time. The finding adds to the understanding of how rising CO2 heats the earth, and how the dynamics of plant life could shift within decades, when CO2 levels may closely mirror those of the distant past.

Scientists retrieved the leaves from a unique onetime New Zealand lake bed that holds the remains of plants, algae, spiders, beetle, flies, fungi and other living things from a warm period known as the early Miocene. Scientists have long postulated that CO2 was high then, and some plants could harvest it more efficiently for photosynthesis. This is the first study to show that those things actually happened in tandem. The findings were published this week in the journal Climate of the Past.

"The amazing thing is that these leaves are basically mummified, so we have their original chemical compositions, and can see all their fine features under a microscope," said lead author Tammo Reichgelt, an adjunct scientist at Columbia University's Lamont-Doherty Earth Observatory and assistant professor of geosciences at the University of Connecticut. "Evidence has been building that CO2 was high then, but there have been paradoxes."

The so-called "carbon fertilization effect" has vast implications. Lab and field experiments have shown that when CO2 levels rise, many plants increase their rate of photosynthesis, because they can more efficiently remove carbon from the air, and conserve water while doing so. Indeed, a 2016 study based on NASA satellite data shows a "global greening" effect mainly due to rising levels of manmade CO2 over recent decades; a quarter to a half of the planet's vegetated lands have seen increases in leaf volume on trees and plants since about 1980. The effect is expected to continue as CO2 levels rise.

This might seem like good news, but the reality is more complex. Increased CO2 absorption will not come close to compensating for what humans are pouring into the air. Not all plants can take advantage, and among those who do, the results can vary depending on temperature and availability of water or nutrients. And, there is evidence that when some major crops photosynthesize more rapidly, they absorb relatively less calcium, iron, zinc and other minerals vital for human nutrition. Because much of today's plant life evolved in a temperate, low-CO2 world, some natural and agricultural ecosystems could be upended by higher CO2 levels, along with the rising temperatures and shifts in precipitation they bring. "How it plays out is anyone's guess," said Reichgelt. "It's another layer of stress for plants. It might be great for some, and horrible for others."

The deposit is located in a small, long-extinct volcanic crater now located on a farm near the southern New Zealand city of Dunedin. The crater, about a kilometer across, once held an isolated lake where successive layers of sediments built up from the surrounding environment. The feature was recognized only within about the last 15 years; scientists dubbed it Foulden Maar. Recognizing it as a scientific gold mine, they have been studying it ever since. Some have also been fighting an actual mining company that wants to strip the deposit for livestock feed.

In the new study, the researchers took samples from a 2009 drill core that penetrated 100 meters to near the bottom of the now-dry lake bed. Larded in between whitish annual layers of silica-rich algae that bloomed each spring for 120,000 years are alternating blackish layers of organic matter that fell in during other seasons. These include countless leaves from a subtropical evergreen forest. They are preserved so perfectly that scientists can see microscopic veins and stomata, the pores by which leaves take in air and concurrently release water during photosynthesis. Unlike most fossils, the leaves also retain their original chemical compositions. It is the only such known deposit in the Southern Hemisphere, and far better preserved than the few similar ones known from the north.

The Miocene has long been a source of confusion for paleoclimate researchers. Average global temperatures are thought to have been 3 to 7 degrees C hotter than today, and ice largely disappeared at the poles. Yet many proxies, mainly derived from marine organisms, have suggested CO2 levels were only about 300 parts per million-similar to those of preindustrial human times, and not enough to account for such warming. With evidence of high CO2 elusive, scientists have speculated that previous proxy measurements must be off.

Based on the new study and a related previous one also at Foulden Maar, the researchers were able to get at this conundrum. They analyzed the carbon isotopes within leaves from a half-dozen tree species found at various levels in the deposit. This helped them zero in on the carbon content of the atmosphere at the time. They also analyzed the geometry of the leaves' stomata and other anatomical features, and compared these with modern leaves. By combining all the data into a model, they found that atmospheric CO2 was not 300ppm, but about 450-a good match for the temperature data. Second, they showed that the trees were super-efficient at sucking in carbon through the stomata, without leaking much water through the same route-a factor that all plants must account for. This allowed them to grow in marginal areas that otherwise would have been too dry for forests. The researchers say this higher efficiency was very likely mirrored in forests across the northern temperate latitudes, with their far greater landmasses.

Human emissions have now pushed CO2 levels to about 415 parts per million, and they will almost certainly reach 450 by about 2040-identical to those experienced by the Foulden Maar forest. Estimates of the resulting temperature increases over decades and centuries vary, but the new study suggests that most are in the ballpark.

"It all fits together, it all makes sense," said study coauthor William D'Andrea, a paleoclimate scientist at Lamont-Doherty. In addition to showing how plants might react directly to CO2, "this should give us more confidence about how temperatures will change with CO2 levels," he said.

Study coauthor Daphne Lee, a paleontologist at New Zealand's University of Otago, led the charge to study Foulden Maar's rich ecosystem after it came to light. More recently, she became an unexpected defender of the maar, when a company with owners in Malaysia and the United Kingdom announced plans to strip-mine the deposit for use as a feed additive for for pigs, ducks and other intensively farmed animals. With many more discoveries probably to be made, scientists were horrified, and allied themselves with locals who feared noise and dust. The Dunedin city council is now looking into buying the land to protect it.

Analysis of three mummified animals - a cat, a bird and a snake - from Ancient Egypt using advanced 3D X-ray imaging is described in a paper published in Scientific Reports. The technique provides insights into the conditions in which the animals were kept, their complex mummification process and their possible causes of death, without causing damage to the specimens.

Richard Johnston and colleagues used non-invasive X-ray microCT imaging to reveal the skull of the cat to be around half the size of the external mummified wrappings. Its morphology suggests that the remains likely belong to an Egyptian domestic cat. Analysis of images of the teeth and skeleton indicate that the cat was less than five months old and may have purposefully had its neck broken at the time of death or during the mummification process to keep the head in an upright position.

Measurements taken using 3D scans of the mummified bird of prey suggest that the remains most closely resemble the Eurasian kestrel and that the animal did not appear to have died from injuries to the neck. Imaging of the tightly coiled snake suggests that the remains belong to a juvenile cobra, which may have been killed by spinal fracture, consistent with tail capture and whipping methods commonly used to kill snakes. The high-resolution imaging enabled the authors to identify structures found within the mouth of the mummified snake as hardened resin. The precise placement at the opening of the glottis possibly provides evidence for complex ritualistic behaviour, similar to the Opening of the Mouth procedure.

An improved understanding of animal mummification through scientific imaging may inform future conservation work and shed light on past human-animal relationships.

Three mummified animals from ancient Egypt have been digitally unwrapped and dissected by researchers, using high-resolution 3D scans that give unprecedented detail about the animals' lives - and deaths - over 2000 years ago.

The three animals - a snake, a bird and a cat - are from the collection held by the Egypt Centre at Swansea University. Previous investigations had identified which animals they were, but very little else was known about what lay inside the mummies.

Now, thanks to X-ray micro CT scanning, which generates 3D images with a resolution 100 times greater than a medical CT scan, the animals' remains can be analysed in extraordinary detail, right down to their smallest bones and teeth.

The team, led by Professor Richard Johnston of Swansea University, included experts from the Egypt Centre and from Cardiff and Leicester universities.

The ancient Egyptians mummified animals as well as humans, including cats, ibis, hawks, snakes, crocodiles and dogs. Sometimes they were buried with their owner or as a food supply for the afterlife.

But the most common animal mummies were votive offerings, bought by visitors to temples to offer to the gods, to act as a means of communication with them. Animals were bred or captured by keepers and then killed and embalmed by temple priests. It is believed that as many as 70 million animal mummies were created in this way.

Although other methods of scanning ancient artefacts without damaging them are available, they have limitations. Standard X-rays only give 2-dimensional images. Medical CT scans give 3D images, but the resolution is low.

Micro CT, in contrast, gives researchers high resolution 3D images. Used extensively within materials science to image internal structures on the micro-scale, the method involves building a 3D volume (or 'tomogram') from many individual projections or radiographs. The 3D shape can then be 3D printed or placed into virtual reality, allowing further analysis.

The team, using micro CT equipment at the Advanced Imaging of Materials (AIM) facility, Swansea University College of Engineering, found:

The cat was a kitten of less than 5 months, according to evidence of unerupted teeth hidden within the jaw bone.

Separation of vertebrae indicate that it had possibly been strangled

The bird most closely resembles a Eurasian kestrel; micro CT scanning enables virtual bone measurement, making accurate species identification possible

The snake was identified as a mummified juvenile Egyptian Cobra (Naja haje).

Evidence of kidney damage showed it was probably deprived of water during its life, developing a form of gout.

Analysis of bone fractures shows it was ultimately killed by a whipping action, prior to possibly undergoing an 'opening of the mouth' procedure during mummification; if true this demonstrates the first evidence for complex ritualistic behaviour applied to a snake.

Professor Richard Johnston of Swansea University College of Engineering, who led the research, said:

"Using micro CT we can effectively carry out a post-mortem on these animals, more than 2000 years after they died in ancient Egypt.

With a resolution up to 100 times higher than a medical CT scan, we were able to piece together new evidence of how they lived and died, revealing the conditions they were kept in, and possible causes of death.

These are the very latest scientific imaging techniques. Our work shows how the hi-tech tools of today can shed new light on the distant past."

Dr Carolyn Graves-Brown from the Egypt Centre at Swansea University said:

"This collaboration between engineers, archaeologists, biologists, and Egyptologists shows the value of researchers from different subjects working together.

Our findings have uncovered new insights into animal mummification, religion and human-animal relationships in ancient Egypt."

What The Study Did: An estimate of the number of African American students who would have graduated from historically Black medical schools that were closed during the period surrounding the 1910 Flexner report was the main outcome of this study.

Authors: Kendall M. Campbell, M.D., of East Carolina University in Greenville, North Carolina, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2020.15220)

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COVID-19 is now the third leading cause of death in the United States. The U.S. accounts for about 25 percent of COVID-19 cases (4.4 million) and deaths (170,000) in the world today while comprising less than 5 percent of the population.

In a commentary published ahead of print in The American Journal of Medicine, researchers from Florida Atlantic University's Schmidt College of Medicine and a collaborator, compare responses to the pandemic from two democratic republics: South Korea and the U.S., demonstrating stark differences in public health strategies, which have led to alarming differences in cases and deaths from COVID-19. After adjusting for the 6.5 fold differences in populations, the U.S. has suffered 47 times more cases and 79 times more deaths than South Korea.

At the beginning of the pandemic, South Korea had more COVID-19 cases than anywhere else in the world outside of China. Today, they have approximately 14,269 cases and 300 deaths. Ironically, the public health methods they employed closely followed those developed and introduced by the U.S. Centers for Disease Control and Prevention (CDC), which formerly served as a scientific beacon for such activities worldwide. South Korea instituted effective containment and mitigation strategies, which they maintained in place until new cases and deaths were practically nonexistent.

In contrast to South Korea, the U.S. government mounted a delayed and fragmented response, which they maintained only until a "flattening of the curve," according to the researchers. Further, containment and mitigation strategies were piecemeal and resulted from individual responses of individual states. Ironically, following the 2013 prediction of an impending pandemic by the Gates Foundation, it was the U.S. government that created a Pandemic Emergency Response Task Force, placing the U.S. as No. 1 worldwide by the World Health Organization (WHO) in their ability to contain and mitigate any future pandemics. This task force was disbanded in 2017, and today the U.S. in the No. 1 spot worldwide in COVID-19 cases and deaths.

In addition, the U.S. government has removed the CDC from its decades' long functions of receiving and providing analyses of surveillance data on COVID-19. The authors note that this continues a longstanding trend of politicization of the CDC, which is producing continuing harm to its longstanding reputation of worldwide respect and admiration.

"The anticipated number of deaths from COVID-19 may become comparable to the most lethal epidemic of influenza in U.S. history, which occurred from 1918 to 1919 when approximately 675,000 Americans died," said Charles H. Hennekens, M.D., Dr.PH, senior author and the first Sir Richard Doll Professor and senior academic advisor in FAU's Schmidt College of Medicine. "In stark contrast to both the current U.S. epidemic of COVID-19 and the Spanish Flu of 1918-19, the 2018-19 flu season affected about 42.9 million Americans, of which 647,000 were hospitalized and about 61,200 died."

The authors raise the specter that, if the current numbers of cases and deaths and their trajectories in the U.S. continue, a coordinated national shutdown of sufficient duration, which was not achieved previously, may become necessary. For example, the continued exponential growth of the virus in the U.S. is reflected by the markedly decreasing number of days to achieve each million case from 97 to 44 to 28 to 15 days.

The U.S. remains the epicenter of the pandemic worldwide, due, at least in part, to the massive surge in cases in Florida, California, Arizona, and Texas. Moreover, only California and Texas have issued statewide mask mandates. The authors further state that the failure to mitigate COVID-19 in the U.S. will paralyze the healthcare delivery system as well decrease the ability to provide lifesaving measures for patients with COVID-19 or other serious conditions. They further state that it is more imperative than ever that the U.S. abandon "pandemic politics" and focus solely on effective public health strategies.

Measures such as those employed by South Korea, especially widespread, free and rapid, point-of-care testing, meticulous tracing and quarantine of all contacts as well as masking, social distancing, crowd avoidance, and frequent hand and face washing, are likely to be at least as effective as any safe vaccine that may be developed and approved for widespread use by the general public in the U.S. and worldwide.

"In the U.S., there is an urgent need for a unified national approach for the implementation of effective public health mitigation strategies including social distancing, masking, avoidance of crowds, as well as frequent hand and face washing," said Joshua Solano, M.D., first author and an assistant professor of integrated medical science and director of quality improvement and patient safety in FAU's Schmidt College of Medicine.

South Korea is not alone in serving as a model for the world for COVID-19 as similar successes have been achieved in New Zealand, Australia, Canada, Germany, Iceland, the United Arab Emirates, Greece and Argentina.

Materials scientists from Nanyang Technological University, Singapore (NTU Singapore) have invented a new type of surgical glue that can help join blood vessels and close wounds faster and may also serve as a platform to deliver pain relief drugs.

In a paper published in Elsevier's Biomaterials in July jointly with clinicians from Singapore General Hospital (SGH), the NTU researchers showed that their glue can bond soft tissues including muscle and blood vessels, even when their surfaces are wet.

Named CaproGlu, it is activated by a low dose of ultraviolet (UV) light that cures it in seconds, turning it from a liquid glue into a solid but flexible biorubber - a biocompatible material that can be resorbed by the tissue after a few weeks.

The team showed in animal experiments that blood vessels can be rejoined with just four stitches and a mesh wrapper dipped in CaproGlu, compared to the usual eight stitches that are required for a reliable and unobstructed join. The authors estimate that this will reduce surgery time by 25 per cent, as surgeons spend less time and effort stitching up blood vessels and tissues.

As demonstrated in animal experiments, CaproGlu can also be used to deliver local anaesthetics or pain relief medication to tissues in the body, which may be useful both during and after an operation and would reduce the need for pain relief medication to be administered afterwards.

Unlike current bio-adhesives - which need two chemicals to be mixed prior to use - the CaproGlu is a one-pot liquid gel solution that comes ready-to-use.

Lead authors of the paper, Associate Professor Terry W.J. Steele and Senior Research Fellow Dr Ivan Djordjevic, emphasised that most surgical adhesives available on the market do not work in water or wet environments as found in the human body.

"To make our light-activated glue work on wet tissues, we engineered our glue to first remove water from the surface and thus allow adhesion to the dehydrated surfaces," said Assoc Prof Steele.

"This unique advantage of being able to bond with high strength in a wet environment, as well as being biocompatible, is what makes CaproGlu so suitable to be used in surgery and medical applications."

The adhesion strength of CaproGlu was compared to other commercial bioadhesives on the market and was found to be three to seven times stronger, and is on a par with the shear strength of collagen and muscle tissue found in the human body.

Benefits of CaproGlu

Invented by Assoc Prof Steele and Dr Djordjevic from the NTU School of Materials Science and Engineering, CaproGlu combines two ingredients into a single-component formulation that does not require additives.

The first is polycaprolactone - a biodegradable polymer which has been approved by the United States Food and Drug Administration for specific applications used in the human body - and the second: diazirine, a light-sensitive molecule that can form strong bonds when activated.

In their research paper which was published in the scientific journal Biomaterials, the scientists demonstrated how CaproGlu could be used as part of a new surgical method, where sutures are used in combination with a glue. Instead of the conventional eight stitches needed to join the two ends of a blood vessel in a rabbit, they used four stitches and wrapped the vessel ends with a biodegradable mesh dipped in CaproGlu and cured with a small dose of UV light which crosslinked the amino acids on the tissue's surface

As a result, the bleeding from the artery immediately after the procedure was comparable to what is observed from conventional stitches. When harvested seven days later, the artery was shown to have completely healed.

In a separate experiment, the surgeons inserted CaproGlu loaded with anaesthetics within rats' calves and cured them with UV light before the wound was closed with conventional stitches.

The scientists compared the activity of these rats with two other controls: rats who had received anaesthetics alone and rats who had received CaproGlu without anaesthetics. They found no discernible impediment of movement for the rats which had anaesthetics and CaproGlu loaded with anaesthetics, suggesting that CaproGlu is successful in delivering local anaesthetics over time and could be a useful way to extend local anaesthesia beyond its current limits and also to act as a drug delivery platform for medication such as anticoagulants to prevent excessive blood clotting.

The team also observed that there were no discernible side effects to the animals which had CaproGlu implanted in their skin, which suggested that it is safe and biocompatible as expected. Since the bioadhesive dissolves and resorbs within weeks, no follow up clinical visits would be required for its removal.

Stable shelf life after sterilisation

A big challenge for bioadhesives on the market today is to cope with the standard method by which surgical grade equipment and disposables are sterilised using gamma irradiation.

The gamma sterilisation process destroys proteins and activates bonding in both acrylate and epoxy adhesives.

Unlike other surgical adhesives available on the market, CaproGlu's protein-free formulation exploits new crosslinking chemistry unaffected by gamma sterilisation.

The light-activated bonding mechanism forms chain links to amino acids at the nanoscale level, even after several months of storage and gamma sterilisation, thus making CaproGlu's production and commercialisation potentially less costly than those based on proteins and acrylates.

Their biorubber glue innovation took the research team five years to develop and is the subject of a provisional patent filed through NTUitive, the university's innovation and enterprise company.

Funding and support for the project include the NTU-Surgery Academic Clinical Programme Strategic Joint Research Fund, Singapore General Hospital Research Grant, NTU-Northwestern Institute for Nanomedicine Grant, NTUitive Proof of Concept (Gap) Fund, A*Star industry Alignment Fund (Pre-Positioning) and the Ministry of Education Tier 1 & 2 research fund.

Moving forward, the joint team will be looking to conduct further animal experiments and to assess the performance of CaproGlu in other applications, such as on bone and other organic surfaces.

Scientists at Johns Hopkins Medicine, experimenting with a small number of human cell samples, report that the "hook" of cells used by SARS-CoV-2 to latch onto and infect cells is up to 700 times more prevalent in the olfactory supporting cells lining the inside of the upper part of the nose than in the lining cells of the rest of the nose and windpipe that leads to the lungs. These supporting cells are necessary for the function/development of odor-sensing cells.

The findings, from a preliminary study of cells lining both the nose and trachea, could advance the search for the best target for topical or local antiviral drugs to treat COVID-19, and offers further clues into why people with the virus sometimes lose their sense of smell.

A summary of the findings appears in a letter published Aug. 19 in the European Respiratory Journal.

"Loss of the sense of smell is associated with COVID-19, generally in the absence of other nasal symptoms, and our research may advance the search for a definitive reason for how and why that happens, and where we might best direct some treatments," says Andrew Lane, M.D., professor of otolaryngology-head and neck surgery, and director of the Division of Rhinology and Skull Base Surgery at the Johns Hopkins University School of Medicine.

Lane's medical practice focuses on people with nasal and sinus problems, who oftentimes, he says, lose their sense of smell -- a condition called anosmia.

Scientists have known that SARS-CoV-2 latches on to a biological hook on the surface of many types of human cells, called an angiotensin-converting enzyme 2 receptor (ACE2). The receptor reels in essential molecules.

In a bid to explore the ACE2 link to COVID-19 in more detail, Lane, Mengfei Chen, Ph.D., a research associate in Lane's lab at the Johns Hopkins University School of Medicine, and others on his team took a close look at ACE2 levels in nasal tissue specimens from 19 adult men and women with chronic rhinosinusitis (inflammation of nasal tissue) and in tissues from a control group of four people who had nasal surgeries for issues other than sinusitis.

The researchers also studied tissue samples of the trachea from seven people who underwent surgery for abnormal narrowing of the trachea.

Cells from children were not examined for this study, in part because they tend to have low ACE2 levels in the cells lining the nose, which may contribute to generally less severe illness among children infected with the SARS-CoV-2 virus. None of the study participants had been diagnosed with COVID-19.

The scientists used a high-resolution imaging technique called confocal microscopy to produce very sharp images of cells lining the nasal and tracheal airways. They used fluorescent stains to identify ACE2 receptors.

They found high levels of ACE2 among nasal cells that give structural support called sustentacular cells. These cells are located in an area called the olfactory neuroepithelium, where odor-sensing neurons are found. The researchers say this area of the nose may be particularly vulnerable to infection and might be the only infected site even when there are no symptoms. Because of this, they urge people to wear masks and wear them correctly.

For the study, depending on the biopsy sample, cells in the olfactory neuroepithelium had a 200-fold to 700-fold increase in ACE 2 proteins compared with other samples from the nose and trachea. Because the cells with high levels of ACE2 are associated with odor sensing, the researchers suggest that infection of these cells may be the reason some people with COVID-19 experience loss of smell.

Two of seven trachea specimens had low levels of ACE2 receptors, and the amount of those receptors was similar between study participants with and without chronic rhinosinusitus.

Because the cells lining the nose may prove to be a key entry point for SARS-CoV-2, Lane says there may be ways to target those particular cells with topical antiviral drugs or other therapies directly to that area.

The researchers plan to advance this research by investigating COVID-19-infected tissue from the noses of humans to confirm if the SARS-CoV-2 virus does indeed target support cells in the nose.

"This particular work not only gives information about stimulating aquathermolysis in the process of steam injection, but also is a theoretical insight into chemical reactions taking places in oil reservoirs under high temperatures," says co-author Yuan Chengdong, Senior Research Associate of the Rheological and Thermochemical Research Lab.

So far, the KFU team has proven copper compounds are the most effective in producing catalysts for heavy oil extraction.

"To that end, we took a model component of a certain type of petroleum and modeled its decomposition into simpler components with the use of different catalysts. We have created a table of catalyst effectiveness, where copper is currently the best, followed by cobalt and nickel," says Head of Petroleum Research, Chair of the Department of Heavy Hydrocarbons Mikhail Varfolomeev.

The work used methods of quantum chemistry, which required joint efforts from geologists, chemists, and mathematicians.

In this paper, cyclohexyl phenyl sulfide (CPS) was selected as a model compound of sulfur-containing oil components, and, for the first time, a catalytic effect of transition metals on the thermochemistry and kinetics of its aquathermolysis was investigated by the density functional theory (DFT) methods with the use of the Becke three-parameter Lee-Yang-Parr (B3LYP), ωB97X-D, and M06-2X functionals. Calculation results show that the hydrolysis of CPS is characterized by fairly high energy barriers in comparison with other possible reaction routes leading to the cleavage of C-S bonds, while the heterolysis of C-S bonds in the presence of protons has a substantially lower kinetic barrier. According to the theoretical analysis, transition-metal ions significantly reduce the kinetic barrier of heterolysis. The Cu2+ ion outperforms the other investigated metal ions and the hydrogen ion in the calculated rate constant by 5-6 (depending on the metal) and 7 orders of magnitude, respectively. The catalytic activity of the investigated transition-metal ions is arranged in the following sequence, depending on the used DFT functional: Cu2+ ? Co2+ ? Ni2+ > Fe2+. It is theoretically confirmed that transition-metal ions, especially Cu2+, can serve as effective catalysts in aquathermolysis reactions. The proposed quantum-chemical approach for studying the catalytic aquathermolysis provides a new supplementary theoretical tool that can be used in the development of catalysts for different chemical transformations of heavy oil components in reservoirs due to hydrothermal treatment.

Cells send signals through enzyme cascades, where one enzyme passes the signal to the next. In such cascades, it is crucial that the enzyme recognizes the right substrates to ensure that, for example, a hormone activates the right cellular activities. Protein kinases, the enzymes in such cascades, are usually not sufficiently specific on their own, and therefore they rely on other proteins to physically connect them to the right substrates.

"Currently, we describe signalling enzymes with equations developed for metabolic enzymes," Magnus Kjærgaard explains. "Metabolic enzymes that make energy for our bodies, for example, need to process many substrates per minute. In contrast, signalling enzymes act as switches, and often only need to convert a single substrate to have an effect. Therefore, the equations developed to describe metabolic enzymes are less relevant for signalling enzymes."

For more than a hundred years, biochemists have described the activity of enzymes using the Michaelis-Menten equation, which describes how activity increases with increased substrate equation. When the enzyme is connected to its substrate, it does not matter how much substrate is present. Instead, the speed of the reaction depends on how the enzyme is connected to the substrate and thus on the connector molecule. Until now, we have not had any description of how the structure of such molecules affected enzymatic reactions.

"Normally, the question you are trying to answer is what graph shape describes the enzyme activity. We had a much more fundamental problem," says first-author Mateusz Dyla. "What should we put on the X-axis instead of concentration?"

Connector molecules control cellular signalling

The authors made a model system where they could change the connection between the enzyme and the substrate. They used this to measure how the length of a flexible connector affects the first round of catalysis by the enzyme, which took place in milliseconds. Finally, they ended up with an equation that describes how the speed of the enzyme depends on the connection between enzyme and substrate. This equation suggested that connector molecules play an overlooked role in controlling cellular signalling.

The connection between enzyme and substrate also affects which substrates the enzyme prefers. Substrates that look similar can be very different when the enzyme only processes a single connected substrate.

"It is like the difference between how long it takes me to eat a single hotdog, and how many hotdogs I can eat over a whole week," Magnus explains. "Over the course of a week, I will be limited by how fast I can digest the hotdogs. This is irrelevant to the time it takes to eat the first hotdog. Therefore, the two types of measurements give different results. If you want to understand kinase switches, you have to focus on the first round of catalysis."

In the long-term, this may have implications for the development of drugs targeting kinases in, for example, cancer. Mateusz explains: "We hope that one day it will be possible to make drugs that not only target the enzyme, but also target how it is connected to its substrate."

The results have been published in the international journal PNAS.

As Web services, cloud storage, and big-data services continue expanding and finding their way into our lives, the gigantic hardware infrastructures they rely on--known as data centers--need to be improved to keep up with the current demand. One promising solution for improving the performance and reducing the energy load associated with reading and writing large amounts of data is to confer storage devices with some computational capabilities and offload part of the data read/write process from CPUs.

In a recent study presented at the 2020 USENIX Annual Technical Conference, researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST), Korea, describe a new way of implementing a key-value store in solid state drives (SSDs), which offers many advantages over a more widely used method.

A key-value store (also known as key-value database) is a way of storing, managing, and retrieving data in the form of key-value pairs. The most common way to implement one is through the use of a hash function, an algorithm that can quickly match a given key with its associated stored data to achieve fast read/write access.

One of the main problems of implementing a hash-based key-value store is that the random nature of the hash function occasionally leads to long delays (latency) in read/write operations. To solve this problem, the researchers from DGIST implemented a different paradigm, called "log-structured merge-tree (LSM)." This approach relies on ordering the data hierarchically, therefore putting an upper bound on the maximum latency.

In their implementation, nicknamed "PinK," they addressed the most serious limitations of LSM-based key-value stores for SSDs. With its optimized memory use, guaranteed maximum delays, and hardware accelerators for offloading certain sorting tasks from the CPU, PinK represents a novel and effective take on data storage for SSDs in data centers. Professor Sungjin Lee, who led the study, remarks: "Key-value store is a widely used fundamental infrastructure for various applications, including Web services, artificial intelligence applications, and cloud systems. We believe that PinK could greatly improve the user-perceived performance of such services."

So far, experimental results confirm the performance gains offered by this new implementation and highlight the potential of letting storage devices compute some operations by themselves. "We believe that our study gives a good direction of how computational storage devices should be designed and built and what technical issues we should address for efficient in-storage computing," Prof Lee concludes.

School-based dementia education could deliver much needed empathy and understanding for older generations as new research from the University of South Australia shows it can significantly improve dementia knowledge and awareness among younger generations.

It's an important and timely finding, particularly given the world's ageing population and the prevalence of dementia among older people.

Globally, around 50 million people have dementia. By 2030 this figure is expected to reach 82 million, and by 2050, it could exceed 152 million.

Lead researcher, and cognitive ageing expert, UniSA's Dr Ashleigh Smith, says the findings show how intergenerational dementia education can transform the way we treat older people to encourage a much-needed age-friendly world.

"Children are our future leaders, they're our local shop keepers, bankers, and neighbours. If we're to improve dementia understanding, we need to invest in the education of our children," Dr Smith says.

"Children generally don't know much about people living with dementia - unless they have a family member of family friend that has the condition.

"When children are in primary school, their minds and health beliefs are still malleable; this is when they're open to learning about new ideas. So, it's an ideal time to educate them about challenging topics, like dementia.

"Recent findings from the Lancet commission (into dementia prevention, intervention and care) suggests that a low level of education is the number one risk factor in early life that contributes to later life dementia.

"By teaching children about dementia, we're not only improving their knowledge and fostering positive attitudes towards dementia now, but maybe even reducing their own future risk of dementia as an adult - it's exciting stuff."

The intergenerational dementia education program (entitled Forget me not ) was developed in partnership with the City of Unley, Unley Primary School and aged-care provider ECH.

The program brought together 90 Year four and five students who, over an eight-week period learned about dementia and interacted with older adults, many of whom had a cognitive impairment or dementia diagnosis. Through co-operative activities such as arts and crafts, gardening and playing pool, the older adults took on the role of teachers, mentors and coaches, while the children developed lifelong skills in communication and empathy.

After completing the program, children showed significant increases in dementia knowledge and attitudes, with observed improvements in communication, empathy and understanding, inclusivity and personhood (viewing a someone with dementia as a valued individual and person).

The older people also enjoyed the interaction, felt engaged with community and that they were valued members of society.

"Dementia education is a critical step for building empathetic, insightful and caring communities," Dr Smith says.

"You only need to look at the current state of Australia's aged care system to see the acute need for better education in this area.

"We know this type of education works; the next step is to find ways to upscale this more broadly."

Orange, Calif. - Research from Chapman University provides new insight into the characteristics of crucial proteins within the ciliary membrane that play vital roles in human genetic diseases and cardiovascular functions.

Recently, primary cilium, an organelle that exist on the surface of almost every cell type in the body, is shown to have membrane swelling. This is referred to as ciliary bulbs, and their structure and physiological relevance remains unknown.

Ashraf Mohieldin, Ph.D., a postdoctoral fellow at the Chapman University School of Pharmacy and principal investigator of the study, led a team to examine and analyze the structure of primary cilia to better comprehend ciliary bulbs and its significance. Using a single-cell, single-cilium imaging technique and proteomic identification, they discovered that a ciliary bulb has extracellular vesicle (EV)-like characteristics.

Extracellular vesicles are known to facilitate information within cardiovascular cells. Mohieldin's team found that ciliary extracellular-like vesicles (cELV) share similarities with EV, and that it plays a specific role in ciliary signaling, cellular functions and maintaining cardiovascular homeostasis. Primary cilia's membrane contains these sensory proteins that detect signals from other cells and in the nearby environment. Serving as the cellular compartments that regulate essential signaling pathways, the protein's signal detection activates the cell's response and behavior. Evaluating from a database of 172 cELV proteins, the researchers also identified that cELV has a unique and dynamic movement and the ability to be released by mechanical fluid force.

Defects in the primary cilia has been associated with a wide range of genetic disorders called ciliopathies, which includes Joubert syndrome, Bardet-Biedl syndrome, polycystic kidney disease and Meckel-Gruber syndrome. Ciliopathies are often chronically disabling and life-threatening conditions that affects multiple organ systems.

"Our findings reveal for the first time crucial ciliary proteins that are implicated in ciliopathy disorders," said Mohieldin. "We hope that our research will rejuvenate our understanding and current approach to investigate human genetic diseases."

To screen abnormal cELV function and the protein's role in cardiovascular systems, Dr. Mohieldin's laboratory worked with zebrafish and mice. The researchers observed randomized heart looping, hydrocephalus, and cystic kidney disorders in the zebrafish. In addition, they looked at compensated heart contractility in both the zebrafish and mice to validate and compare the data. Through this, they saw that low circulation of cELV results in hypotension with compensated heart function, left ventricular hypertrophy, cardiac fibrosis and arrhythmogenic characteristics, which result in a high mortality rate in mice. Furthermore, the overall ejection fraction, stroke volume, and cardiac output are significantly decreased in mice lacking cELV. No previous research found cELV's physiological roles in zebrafish and mouse models prior to this.

With this finding of the strong link between cELV and ciliopathies and cardiovascular function, the hope is that future research will focus on these proteins to help discern a viable treatment for disorders associated with cilia dysfunction.

"Targeting these proteins can help scientists to clearly understand the mechanism of these disorders and ultimately lead the path to potential treatments for ciliopathies," said Mohieldin.

Leipzig/New Delhi. The airborne transmission of the coronavirus SARS-CoV-2 via aerosol particles in indoor environment seems to be strongly influenced by relative humidity. This is the conclusion drawn by researchers from the Leibniz Institute for Tropospheric Research (TROPOS) in Leipzig and the CSIR National Physical Laboratory in New Delhi from the analysis of 10 most relevant international studies on the subject. Therefore, they recommend controlling the indoor air in addition to the usual measures such as social distancing and masks. A relative humidity of 40 to 60 percent could reduce the spread of the viruses and their absorption through the nasal mucous membrane. To contain the COVID-19 pandemic, it is therefore extremely important to implement standards for indoor air humidity in rooms with many people, such as hospitals, open-plan offices or public transport, writes the research team in the scientific journal Aerosol and Air Quality Research.

According to the WHO, the coronavirus SARS-CoV-2 has led to at least 21 million infected persons and over 750,000 deaths worldwide in over half a year. The health and economic effects of the pandemic pose major social challenges for practically all countries. Worldwide, therefore, ways are being sought to stem the spread of the virus in order to avoid drastic measures such as lockdowns and contact restrictions. For a long time, the main transmission route of viral droplets was considered to be direct human-to-human contact, because of infected people sneezing or coughing and secreting the virus. Because these drops are relatively large and heavy, they fall very quickly to the ground and can only cover very short distances in the air. The recommendation to keep a minimum distance of 1.5m to 2m (social distancing) is based on this assumption. Recently, however, COVID-19 outbreaks have also been recorded, which seem to be due to the simultaneous presence of many people in one room (choir rehearsals, slaughterhouses, etc.). A safety distance of 1.5m is apparently not sufficient when infected and healthy people are together in one room for a long time. For example, Dutch researchers have now been able to prove that tiny drops of 5 micrometres in diameter, such as those produced when speaking, can float in the air for up to 9 minutes. In July, 239 scientists from 32 countries - including the chemist Prof. Hartmut Herrmann from TROPOS - therefore appealed to the World Health Organization (WHO) to focus more closely on the long-lived infectious particles suspended in the air. In order to contain the spread via the aerosol particles floating in the air, the researchers recommend not only continuing to wear masks but also, and above all, good indoor ventilation.

An Indo-German research team is now pointing out another aspect that has received little attention so far and could become particularly important in the next flu season: Indoor humidity. Physicists at the Leibniz Institute for Tropospheric Research (TROPOS) in Leipzig and the CSIR National Physical Laboratory in New Delhi have been studying the physical properties of aerosol particles for years in order to better estimate their effects on air quality or cloud formation. "In aerosol research, it has long been known that air humidity plays a major role: The more humid the air is, the more water adheres to the particles and so they can grow faster. So, we were curious: what studies have already been conducted on this," explains Dr. Ajit Ahlawat from TROPOS.

Therefore, they evaluated a total of 10 most relevant international studies between 2007 and 2020 by other researchers who investigated the influence of humidity on survival, spread and infection with the pathogens of influenza and the corona viruses SARS-CoV-1, MERS and SARS-CoV-2. Result: Air humidity influences the spread of corona viruses indoors in three different ways: (a) the behaviour of microorganisms within the virus droplets, (b) the survival or inactivation of the virus on the surfaces, and (c) the role of dry indoor air in the airborne transmission of viruses. Although, low humidity causes the droplets containing viruses to dry out more quickly, the survivability of the viruses still seems to remain high. The team concludes that other processes are more important for infection: "If the relative humidity of indoor air is below 40 percent, the particles emitted by infected people absorb less water, remain lighter, fly further through the room and are more likely to be inhaled by healthy people. In addition, dry air also makes the mucous membranes in our noses dry and more permeable to viruses," summarizes Dr. Ajit Ahlawat.

The new findings are particularly important for the upcoming winter season in the northern hemisphere, when millions of people will be staying in heated rooms. "Heating the fresh air also ensures that it dries. In cold and temperate climate zones, therefore, the indoor climate is usually very dry during the heating season. This could encourage the spread of corona viruses," warns Prof. Alfred Wiedensohler of TROPOS. The air humidity determines how much water a particle can bind. At higher air humidity, the surface of the particles changes considerably: a kind of water bubble forms - a miniature ecosystem with chemical reactions. The liquid water content of aerosols plays an important role in many processes in the atmosphere, as it influences the optical properties, leading for example to haze or altered effects of aerosols on the climate.

At a higher humidity, the droplets grow faster, fall to the ground earlier and can be inhaled less by healthy people. "A humidity level of at least 40 percent in public buildings and local transport would therefore not only reduce the effects of COVID-19, but also of other viral diseases such as seasonal flu. Authorities should include the humidity factor in future indoor guidelines," demands Dr. Sumit Kumar Mishra of CSIR - National Physical Laboratory in New Delhi. For countries in cool climates, the researchers recommend a minimum indoor humidity. Countries in tropical and hot climates, on the other hand, should take care that indoor rooms are not extremely undercooled by air conditioning systems. When air is extremely cooled, it dries out the air and the particles in it, making people inside the room feel comfortable. But the dry particles will remain in the air for longer duration.

From a researchers' point of view, more attention should be paid to indoor air to prevent future outbreaks of viral disease. The moisture content of indoor air is an important aspect but not the only one. Fresh air from outside can also reduce the risk of transmission. And of course, the measures already known and practised: Keep social distancing, having as few people per room volume as possible, and wearing masks. The lowest risk of infection still where there are no viruses in the air. Tilo Arnhold

It is no secret that people underlie social influences. For example, at the lunch counter of a new company, when we are unsure which dish would taste good, we monitor other peoples' choices to obtain some guidance for our own menu selection. This phenomenon, which is referred to as social influence, was demonstrated experimentally starting in the 1950s by social psychologist Solomon Asch.

In the new study, researchers from the University Medical Center Hamburg-Eppendorf (UKE) in Germany placed groups of five volunteers in the same computer-based decision-making experiment, where each of them was presented with two abstract symbols. Their objective was to find out which symbol would lead to more monetary rewards in the long run. In each round of the experiment, every person first made a choice between the two symbols, and then they observed which symbols the other four people had selected; next, every person could decide to stick with their initial choice or switch to the alternative symbol. Finally, a monetary outcome, either a win or a loss, was delivered to every one according to their second decision. "This way, we enable real-time interactions among the volunteers, which greatly enhances ecological validity, " says study leader Lei Zhang, then at the UKE and now a postdoctoral researcher at the University of Vienna.

In fact, which symbol was related to more reward was always changing. At the beginning of the experiment, one of the two symbols returned monetary rewards in 70% of the time, and after a few rounds, it provided rewards in only 30% of the time. These changes took place multiple times throughout the experiment. "This so-called reversal learning paradigm will create uncertainty for volunteers so that they will always need to learn and relearn to gain more outcomes. In particular, when the reversal just happened, some people in the group may pick it faster than the others, and if so, the others could combine this social information into their own decision-making processes, " explains Jan Gläscher, who leads a research group on valuation and social decision-making at the UKE.

Expectedly, the volunteers switched more often when they were confronted with opposing choices from the others, but interestingly, the second choice (after considering social information) reflected the reward structure better than the first choice. How to explain this finding? The researchers used sophisticated models to quantify volunteers' behavior, and they unveiled separate computational strategies for direct learning and social learning. "At the beginning of each round, the volunteers were combining their own direct learning experience and social learning experience to guide their choice," Zhang says, "whereby direct learning follows a simple reinforcement learning algorithm, and social learning is instantiated by tracking the others' reward history."

Within each group, the researchers scanned one of the volunteers' brain using functional magnetic resonance imaging, which allowed them to measure when and where the brain carries out both direct learning and social learning, and to characterize whether the two types of learning actually are associated with different neural signatures. The brain scans showed that direct learning is represented in the area called the ventromedial prefrontal cortex, whereas social learning is represented in the area called the anterior cingulate cortex. These two areas also interact with an area in the middle of the brain called the striatum, "which computes both reward prediction error and social prediction error, quantifying trial-and-error learning to inform behavior" says Gläscher. "These indicate an integrated brain network supporting social influence in human decision-making."

These findings suggest that two unique types of learning signals are computed in distinct but interacting regions in the human brain, and represent separate computational strategies for decision-making in social contexts. "Direct learning is efficient in stable situations," explains Gläscher, "and when situations are changing and uncertain, social learning may play an important role together with direct learning to adapt to novel situations, such as deciding on the lunch menu at a new company."

"There has been a lot of research on direct learning but relatively little on social learning and how they interact, " Zhang says. What is next? "An important area for further research will be to disrupt part of the identified network using non-invasive brain stimulation techniques, and to determine how behaviors and computation strategies are altered in social decision-making, " Gläscher says. "And in light of the ongoing COVID-19 pandemic, there is no way individuals and governments learn from mistakes all by themselves, and instead, a global and collective human society is needed to address all these challenges."

Imagine that the size of a bacterium is measured from a distance of about 4500 light-years. This would be an incredible measurement, considering that a bacterium is so small that a microscope is required to see it, and what an enormous distance light can travel in 4500 years, given that it can round the Earth more than seven times in just one second. But a small deformation of the size of a bacterium, that is an extra height of a few micrometres in one direction, has now been inferred for a neutron star at a distance of about 4500 light-years, from a research by Prof. Sudip Bhattacharyya of the Tata Institute of Fundamental Research (TIFR), India. This research is published in a new paper in Monthly Notices of the Royal Astronomical Society.

Neutron stars are incredibly dense cosmic objects. They are about the size of a city, but contain more material than in the Sun, and a handful of stellar stuff would outweigh a mountain on the Earth. Some of them are observed to spin several hundred times in a second, and we call them millisecond pulsars. A slight asymmetry or deformation around the spin axis of such a star would cause the emission of gravitational waves continuously.

Gravitational waves, which are ripples in spacetime, have recently provided a new window to the universe. But so far they have been found as transient phenomena of mergers of black holes and neutron stars. Continuous gravitational waves, for example from a slightly deformed and spinning neutron star, have so far not been detected. The current instruments may not have the capability to detect these waves, if the deformation is too small.

However, a way to indirectly infer such waves and to measure this deformation is to estimate the contribution of the waves to the spin-down rate of the pulsar, which was not possible till now. PSR J1023+0038 is a unique cosmic source for this purpose, because it is the only millisecond pulsar for which two spin-down rates, in the phase of mass transfer from the companion star and in the phase when there is no mass transfer, were measured. Using these values, and primarily a fundamental principle of physics, that is the conservation of angular momentum, Bhattacharyya has inferred continuous gravitational waves and has estimated the neutron star's microscopic deformation.