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Professor Yutaka Amao of the Osaka City University Artificial Photosynthesis Research Center and Ryohei Sato, a 1st year Ph.D. student of the Graduate School of Science majoring in Physics and Chemistry, reveal that the catalyst formate dehydrogenase reduces carbon dioxide directly to formic acid.

The development of an effective catalyst is an important step in creating an artificial photosynthesis system that uses sunlight to convert carbon dioxide into organic molecules. Formate dehydrogenase (FDH) is a catalyst that accelerates the reaction of converting carbon dioxide (CO2) into formic acid (hydrogen energy storage medium etc.) However, until now the details of how this happened were unclear. The research group dissolved FDH in a liquid solution and carbon dioxide was then blown into the solution for the reaction event.

In liquid, carbon dioxide exists in two additional forms other than itself - biocarbonate ion and carbonate ion. Until now, it was not known which of these three forms is reduced and converted into formic acid. By changing the amount of each type of carbon dioxide in the liquid solution and controlling them precisely the group found that carbon dioxide itself is directly reduced to formic acid after investigating their reaction with FDH.

The results of this research were published in the New Journal of Chemistry published by the Royal Society of Chemistry (RSC).

With the development of science and technology, it is necessary to prepare for the next generation by promptly solving the serious problems of today, namely global warming due to greenhouse gases, processing of large amounts of industrial waste, and the depletion of fossil energies such as oil and coal. It is essential to build an energy recycling system with a low environmental impact and to develop an energy conversion system that effectively uses greenhouse gases such as carbon dioxide. CO2 has a reduction target set on a global scale. It is possible to regulate and reduce CO2 emissions, but how to use this as a raw material and convert it into useful substances is also an important issue. These are the circumstances that have drawn attention to artificial photosynthesis technology that uses solar energy to convert carbon dioxide into a usable fuel. This research group aims to dramatically improve the catalyst "formate dehydrogenase", which promotes the reaction of converting carbon dioxide into formic acid (fuel, chemical products, energy storage medium). It is known that carbon dioxide exists in a liquid as biocarbonate ion (HCO3-) and carbonate ion (CO3-) in addition to itself. However, when a reaction in the solution is catalyzed by formate dehydrogenase, it was unclear which of the 3 forms of CO2 was reduced to formic acid.

By changing the amount of these three forms of CO2 in the liquid solution and controlling them with formate dehydrogenase, This study showed that they are reduced to formic acid only when the carbon dioxide ratio is large, as shown in the figure to the right. When the carbon dioxide in the solution was changed to a bicarbonate and carbonate, it was not reduced to formic acid.

We believe that this discovery will guide us in the development and design of catalysts that will help bring about an artificial photosynthesis system that efficiently converts carbon dioxide into organic molecules.

Although all cells in an organism have the same genetic information, not all perform the same function, being as not all of them have the same active genes. Part of these differences in gene activity is due to DNA methylation, a process of silencing that labels genes in order to keep them "off" when they are not necessary. These labels are key epigenetic marks for the organism and are related to diseases such as cancer, since when they are uncontrolled, they can end up silencing important genes for normal cell activity.

A research team at the University of Cordoba established just that: a new way to reactivate silenced genes and has developed a tool that allows for advancing in epigenome editing. The epigenome is the name for the set of epigenetic marks that regulates gene expression and acts as an on/off switch for genes.

The research, carried out by the Epigenetics and DNA Repair research group, led by Genetics Professor María Teresa Roldán Arjona, focused on 5-methylcytosine, the methylated DNA form that causes gene silencing. "Our aim was to design a system that eliminates this methylcytosine from specific places in the genome and susbstitutes it for unmethylated cytosine, so as to once again turn on those silenced genes", points out Genetics Professor Rafael Rodríguez Ariza, member of the research team.

Specifically, the study used the tool known as CRISPR, a genetic editing technique that uses RNA guides to direct a protein (Cas9) to specific places on DNA and stop it. "In this case, an inactive version of the Cas9 protein was used, given that our aim was not to eliminate a DNA sequence, but rather to remove some of the labels responsible for gene silencing", says the researcher.

To do so, the research project used a plant enzyme called ROS1 that erases these molecular labels. This is a protein that is only present in plants and that releases DNA from these marks directly, something that differentiates it from animal proteins that only work indirectly and in a more complex way. The strategy consists of inserting ROS1 into in-vitro cells, along with RNA and inactive Cas9 protein, to guide it to the gene that is to be reactivated.

The new tool, along with other previously existing ones, is another step further in epigenetic editing and in understanding DNA methylation, the action that translates into silencing genes and is linked to important pathological processes.

Gesturing with the hands while speaking is a common human behavior, but no one knows why we do it. Now, a group of UConn researchers reports in the May 11 issue of PNAS that gesturing adds emphasis to speech--but not in the way researchers had thought.

Gesturing while speaking, or "talking with your hands," is common around the world. Many communications researchers believe that gesturing is either done to emphasize important points, or to elucidate specific ideas (think of this as the "drawing in the air" hypothesis). But there are other possibilities. For example, it could be that gesturing, by altering the size and shape of the chest, lungs and vocal muscles, affects the sound of a person's speech.

A team of UConn researchers led by former postdoc Wim Pouw (currently at Radboud University in the Netherlands) decided to test whether this idea was true, or just so much hand waving. The team had volunteers move their dominant hand as if they were chopping wood, while continuously saying "a" as in "cinema." They were instructed to keep the "a" sound as steady as they could.

Despite that instruction, when the team played audio recordings of this to other people, they found the listener could hear the speaker's gestures. When the listener was asked to move their arms to the rhythm, their movements matched perfectly with those of the original speaker.

Because of the way the human body is constructed, hand movements influence torso and throat muscles. Gestures are tightly tied to amplitude. Rather than just using your chest muscles to produce air flow for speech, moving your arms while you speak can add acoustic emphasis. And you can hear someone's motions, even when they're trying not to let you.

"Some language researchers don't like this idea, because they want language to be all about communicating the contents of your mind, rather than the state of your body. But we think that gestures are allowing the acoustic signal to carry additional information about bodily tension and motion. It's information of another kind," says UConn psychologist and director of the Center for the Ecological Study of Perception and Action James Dixon, one of the authors of the paper.

Many 21st century challenges exist in science and technology, and one of these is the hypersonic vehicle from the dream for human beings to fly faster, higher and further. For developing such the hypersonic vehicle, one of the crucial problems appears to be advanced ground test facilities. After more than sixty year's research work, hypersonic ground test facilities suitable for verification of hypersonic techniques and exploration of the aero-thermochemistry of hypersonic flows still rely on shock tunnels that have some limitations to meet the ever-increasing demand. For reliable ground tests, four requirements must be considered carefully for hypersonic wind tunnel development: (1) The test gas, instead of any substitute, must be the pure air to accurately simulate chemical reaction mechanisms; (2) The stagnation temperature and total pressure must be achieved to excite correct chemical reactions; (3) The scale of test models must be large enough to ensure that chemical reactions occur at the correct reaction rate on the right location of the test models because chemical reactions are not scalable; (4) Sufficient long test time is necessary for aerodynamic forces and supersonic combustion tests. The fourth requirement is important for the test flow to reach stable combustion and improve the experimental data accuracy of aerodynamic forces and moments. Meeting these four requirements at the same time results in the flight condition duplication in ground test facilities, which has been a challenge in developing hypersonic test facilities for decades.

The theory of detonation-driven shock tunnels for developing hypervelocity test facilities is described, covering three important aspects. The first aspect is on the special feature of shock tunnels. The stagnation temperature and the total pressure can be simulated selectively to generate hypersonic flows with a required velocity but at different altitudes if the shock tunnel driver is powerful enough. Two methods can be used to improve shock tunnels' driving ability by increasing the sound speed of the driver gases. One is choosing light-gases as driver gases and other is heating the driver gases to a high temperature level. The detonation driver has a special advantage in generating high temperature driver gases. The second aspect is on the detonation driver concept that is demonstrated to meet the demand from large-scale high-enthalpy testing. This means that the driver is capable of generating test flows with both the high total temperature and the high power for generating large scale test flow fields. Two kinds of the detonation drivers are developed and applied successfully. One is the backward detonation driver for long test duration. The JF-12 hypersonic flight duplicated shock tunnel (Hyper-dragon I) is built up based on this operation mode and becomes the largest hypersonic shock tunnel with a 2.5 m diameter nozzle. Its performance covers Mach numbers from 5-9 and flight altitudes from 25-50 km. The other is the forward detonation cavity (FDC) driver for gaining high flow enthalpy, and this operation mode is tested in the JF-10 detonation-driven high-enthalpy shock tunnel in the Institute of Mechanics, CAS. The test flow of a total temperature up to 7000 K is achieved with a uniform reservoir pressure maintaining for as long as 6 ms. Figure shows the schematic diagram of the FDC driver and its experimental performance data. The last aspect deals with the interface-matching problem. The interface separating test/driver gases can induce the incident shock reflection, therefor, it is a key issue for improving test flow quality and keeping test time as long as possible. The interface-matching condition is proposed by adjusting the initial detonable gas mixture to make the acoustic resistance of its detonated products be the same with the test gas behind the incident shock wave. Shock tunnel experiments showed that two detonation drivers can be operated under the interface-matching condition with the incident Mach number as high as 9. By operating under such the condition, the 100 ms test duration is achieved by the Hyper-dragon I.

Theory of the detonation-driven hypervelocity shock tunnel is described systemically with experimental demonstration. With the theory, it is possible to develop large-scale hypersonic test facilities for thermal-aerodynamic research on hypersonic flows that are chemically reacting.

Microscopic visualization of sub-cellular structures and constituents plays a central role in cell biology. Synchrotron-based X-ray microscopy (XRM) provides a unique approach for direct imaging a whole cell with intrinsic nanoscale resolution. However, existing approaches to label biomolecules rely on the use of exogeneous tags that are multi-step and error-prone (e. g. antibody-based detection). Recently, Chunhai Fan from Shanghai Jiao Tong University, Ying Zhu, Jun Hu and Lihua Wang from the Shanghai Synchrotron Lightsource developed genetically-encoded tags for XRM imaging, which allows nanoscale localization of proteins in cells.

They repurposed peroxidases as genetically-encoded X-ray-sensitive tags for site-specific labeling of protein-of-interest in mammalian cells. They find that polymers that are in-situ catalytically formed by fusion-expressed peroxidases are visible under XRM (Fig. a). The major consequences of using this new tag can be categorized in three aspects: 1) The genetically encoded X-ray tags allow endogenous labeling of diverse molecules and subcellular structures for XRM imaging with an ultrahigh spatial resolution of ~30 nm (Fig. b). 2) The high photostability of X-ray tags enables long-term observation of intracellular and intercellular events. Especially, they visualize the changes of intercellular connections among tumor cells dependent on DNA methylation with XRM. 3) The high energy resolution of XRM provides a direct means to realize multi-colour imaging of cellular structures. This work enlightens the way to nanoscopic imaging for biological studies.

Researchers at New York University and IBM Research have demonstrated a new mechanism involving electron motion in magnetic materials that points to new ways to potentially enhance data storage. The work, reported in the journal Physical Review Letters, unveils a process for setting the direction of the magnetic information, or spin, based on an electrical current.

The discovery stems from the scientific field of spintronics, which considers condensed matter and quantum physics. Spintronics is shorthand for electronics, or electrical devices, that use the electron's spin in addition to its electrical charge.

"One of the major goals of spintronics research is to control the direction of the spin of electrons in materials," explains Andrew Kent, a professor in NYU's Department of Physics and one of the paper's senior authors. "This research shows a new and fundamental mechanism for setting the electron spin direction in a conducting material."

"This advance in spintronics offers a novel way to exert torques on a magnetic layer," adds senior co-author Jonathan Sun of IBM Research and a visiting scholar at NYU. "It's a promising advance that has the potential to reduce energy and space requirements for device data storage."

The work, conducted with Junwen Xu, an NYU graduate student, and Christopher Safranski of IBM Research, is the latest example of a phenomenon central to the transmission of information: altering it from one form to another.

For instance, mobile phones convert voice and emails into radio waves that travel to cell phone towers where the signals are transformed into electrical ones while the internet transforms electrical signals into optical ones (i.e., light pulses) for long-distance transmission.

In the Physical Review Letters research, Safranski, Sun, Xu, and Kent focused on demonstrating a novel mechanism for the control of spin direction--the direction that controls the stored bits of information.

Historically, current flow in non-magnetic heavy metals has been shown to lead to spin polarization, or a direction of its net magnetic moment, at the surface of the conductor, an effect known as the spin Hall effect. However, the direction of the spin polarization in the spin Hall effect is always parallel to the surface of the conductor. This limits its applications because it provides only one possible axis of spin polarization, limiting storage density.

In the Physical Review Letters research, the scientists used the planar-Hall effect in a ferromagnetic conductor to control the orientation of the spin-polarization axis.

Specifically, they deployed a ferromagnetic conductor--iron, nickel, and cobalt are examples of such conductors--and found that current flow in the conductor can produce a spin polarization that is in a direction set by its magnetic moment. This is significant because the magnetic moment direction can now be set in just about any desired direction to then set the spin polarization--a flexibility not possible under the contours of the spin Hall effect in non-magnetic heavy metals.

They also found that these polarized spins travel outside the ferromagnetic layer and lead to a pure spin current--a spin current with no associated electrical current--in an adjacent non-magnetic metal. This phenomenon has the potential to enable a new generation of spin-controlled memory device for higher-density and more efficient memory technology.

When bacteria such as Salmonella or Yersinia cause fever, diarrhoea or abdominal pain, tiny "injection needles" are at work: their type 3 secretion system, or T3SS for short, shoots bacterial virulence proteins directly into the eukaryotic host cells. Researchers have thought of using bacterial injection devices to introduce proteins into eukaryotic cells. A Max Planck research team has now succeeded in controlling the injection system optogenetically, i.e. with light. In the future this will enable to use the system in biotechnological or medical applications.

The T3SS is essential for virulence in many important human pathogens, including Salmonella, Shigella, and pathogenic Escherichia coli, that cause several millions of deaths per year. It is also important in hospital infections, for example by Pseudomonas aeruginosa, where presence of a functional T3SS is associated with higher mortality in animal models and increased antibiotic resistance, severe disease, and a bad prognosis in infected humans.

Consequently, the T3SS is considered a central target for potential therapeutics that could impair its function and prevent infections. On the other hand, hijacking this bacterial system would offer the chance for controlled protein delivery to host cells through the T3SS, like in a trojanic horse. Protein injection through T3SS is fast and efficient: a single injectisome can transfer several thousand effector proteins in few seconds.

However, as powerful as the T3SS injection system is, it is far from accurate - much to the disappointment of the researchers. „As soon as a T3SS contacts any host cell, it fires its load immediately. This is unfavourable for applications in biotechnology or medicine, where we want to target specific cell types, for example in tumour therapy", says Andreas Diepold, Research group leader at the Max-Planck-Institute for Terrestrial Microbiology in Marburg.

Protein injection via on/off switch

But now Andreas Diepold and his team have come a big step closer to this goal: they succeeded in controlling the T3SS injectisome using a molecular light switch. This will enable scientists to inject proteins into eukaryotic cells at a precise time and place. „During my postdoctoral fellowship in Oxford, I discovered that some parts of the T3SS are dynamic", Andreas Diepold recalls. „They are constantly exchanged between this apparatus and the interior of the cell." The scientist applied his findings to the young research field of optogenetics. The principle of this technique is that protein interactions can be controlled with millisecond speed by changing their conformation when stimulated with light of specific wavelengths, thus allowing a fast and specific control of defined molecular processes in biological systems.

Doctoral fellow Florian Lindner coupled the dynamic T3SS component with one part of this optogenetic interaction switch, while its other part was anchored to the bacterial membrane. By exposing bacteria and host cells to blue light, the availability of the T3SS components and consequently the function of the T3SS could be switched on and off.

Applying LITESEC to tumor research

Since the system is flexible in regard to which kind of proteins are injected, it can be used in many ways. In a collaboration with Thorsten Stiewe from the Philipps University in Marburg, the research group used the new system to attack and kill cultured tumour cells. The group now plans to use this technique for future basic research and for the development of further application.

In a recently published study, researchers from Aarhus University document that the risk of atrial fibrillation is not linked to the amount of body fat, but instead to large muscle mass, or more precisely, a high fat-free weight.

Researchers from Aarhus University document that the risk of atrial fibrillation is not linked to the amount of body fat, but instead to a high fat-free weight. Senior Researcher at the Research Unit for General Practice, Morten Fenger-Grøn (picture), is behind the study together with Consultant Cardiologist and Clinical Associate Professor at the Department of Clinical Medicine, Lars Frost.

Atrial fibrillation affects as many as one in three persons in the industrialized/Western world during a lifespan. And when it comes to preventing the condition, the medical doctor's best advise is often weight loss. However, a new study from Aarhus University shows that the risk of atrial fibrillation is not linked to the amount of fat, but rather to the fat-free weight.

Senior Researcher at the Research Unit for General Practice, Morten Fenger-Grøn, is behind the study together with Consultant Cardiologist and Clinical Associate Professor at the Department of Clinical Medicine, Lars Frost.

"While it's correct that overweight individuals have a clearly elevated risk of atrial fibrillation, there is no clear evidence that fat is of any significance when we adjust for these individuals' high fat-free mass. Conversely, it appears that people with high fat-free weight do have a high risk, regardless of whether they have a lot of fat on their body or not," explains Morten Fenger-Grøn.

Overweight has been blamed

The results have just been published in the journal Trends in Cardiovascular Medicine.

"In many people's eyes, large muscle mass is likely seen as the opposite of high body fat, but it turns out that to some extent, the same people have a lot of both. And when these people have a high risk of atrial fibrillation, we tend to interpret it as proof that too much fat is harmful," explains Morten Fenger-Grøn.

According to the researcher, many people have undiagnosed atrial fibrillation.

"Our results point to the importance of remembering to also look for this condition in people who are muscular and without overwhelming body fat - even though they appear to be very healthy and robust," he says.

New cause of atrial fibrillation

However, he emphasises that the results encompass only the risk of atrial fibrillation and do not gainsay that too much body fat increases the incidence of infarctions, diabetes and many other health problems.

"Unfortunately for all of us who struggle with our weight, the results don't provide a basis for ripping all the pages out of the textbooks which warn against being overweight. Yet it's reasonable enough to get rid of the sections that suggest a causal link to atrial fibrillation which runs via inflammation caused by adipose tissue. That in itself may be a very important realisation," says Morten Fenger-Grøn.

He adds:

"It's a reminder that the causal mechanisms behind atrial fibrillation are completely different than those behind many other heart diseases - and sometimes almost the opposite. It's important to really understand this if we are to prevent that the occurrence of atrial fibrillation keeps increasing, while those for other heart conditions are declining."

The research results - more information

The study, which is based on a review of the literature on the importance of body fat and fat-free mass for the risk of atrial fibrillation, also contains a meta-analysis which summarises the results of all relevant studies in the field.

The starting point for the work was, among other things, the research group's own study: "Lean Body Mass Is the Predominant Anthropometric Risk Factor for Atrial Fibrillation", in which they analysed the body mass of 56,000 participants in the Danish 'Diet, Cancer and Health' project.

Magnetic field sensors are largely used in industry, medicine, as well as in applied and fundamental physics. For example, it is impossible to assemble a car without magnetic sensors. Viktor Belyaev and Valeria Rodionova, researchers at the Laboratory of Novel Magnetic Materials at the Immanuel Kant Baltic Federal University, together with colleagues at the Laboratory of Nano-Optics and Metamaterials at the Department of Physics at the Lomonosov Moscow State University, have developed a sensor that combines advances in the fields of magnetism, optics, and solid-state physics. The sensor can be applied in both industry and biomedicine. It is worth noting that the sensor was patented last year.

In April 2020, an article "Magnetic field sensor based on magnetoplasmonic crystal" was published in Scientific Reports magazine. Work on the subject of the article has been going on with colleagues from Lomonosov Moscow State University for several years. The article tells about the principles of creating a high-local and highly sensitive sensor magnetic field by strengthening the magneto-optical effects due to the concentration of the electromagnetic field of the light wave in the near-surface area of the sensor. In other words, optimal parameters for making nanostructures have been found, which allow to significantly enhance the interaction of magnetic material and light.

The sensor developed by researchers allows mapping magnetic fields from different objects, which is potentially important for flaw detection and biomedical applications.

Viktor Belyaev:

"A recent article from our laboratory in a special issue of Sensors magazine describes the principles of most currently developed magnetic field measurement techniques for biomedical applications, and we are confident that soon our sensor will also be added to such reviews due to its unique advantages. This cycle of research was conducted jointly with the Laboratory of Nano-Optics and Metamaterials of the Faculty of Physics at the Lomonosov Moscow State University. Our colleagues at Toyohashi University of Technology (Japan) have made an important contribution to our research by providing equipment for the manufacturing of nanomaterials. The published work is an important step in the joint research of magnetic and magneto-optical properties of magnetoplasmonic crystals, but it is for from nearing completion. It is always a pleasure to realize that there are many new discoveries yet to be made".

Phasmatodea, commonly known as stick insects and leaf insects, are icons of crypsis and primary defense specialization, exhibiting a wide range of remarkable morphological and behavioral modifications associated with camouflage. Most of extant stick and leaf insects have the appearance of abdominal extensions, which has been one of the innovations contributing to their extraordinary crypsis. However, the early origin and evolution of mimetic and defensive strategies within Phasmatodea are meager understanding.

Yang et al. reported the earliest mimetic and defensive strategies of a stick insect from the Middle Jurassic of China, Aclistophasma echinulatum gen. et sp. nov., exquisitely preserving a combination of characters associated with both mimicry and defense, such as abdominal extensions, femoral spines, and large fore- and hind wings. The presence of these characters imply a remarkably early evolution of such specializations and their associated functions among some of the earliest Phasmatodea, suggesting that these defining and iconic aspects of stick insect evolution appeared early and are among taxa that are otherwise considered as stem groups to the more typical members (Timematodea + EuPhasmatodea) of the order today.

The result of phylogenetic analyses based on characters of the wing venation indicated A. echinulatum was affiliated with Susumanioidea, and recovered three clades of Susumanioidea: Phasmomimoidinae, Susumaniinae, and the new subfamilial clade Aclistophasmatinae. Susumanioidea, as a true stem-group of Phasmatodea, has a closer relationship with modern Phasmatodea than other Mesozoic winged groups (except Pterophasmatidae). Moreover, the possible phylogeny of fossil and extant stick insects is provided and discussed.

The distribution of abdominal extensions and femoral spines are mapped onto the phylogeny of Phasmatodea, suggesting that abdominal extensions and femoral spines should develop multiple times during the evolution of stick insects. The appearance of abdominal extensions predates other expansions of the body, such as those of the sterna and pleura, as well as defensive femoral spines.

Interestingly, A. echinulatum possesses a combination of characters associated with mimicry and active defense, including a large body size, large wings, extended abdominal terga with marginal spicules, and distinct femoral spination. Most of all, the form of the tergal extensions was similar to the overall form of various leaves in size and shape from ferns that coexisted in the same deposits. Such a close approximation likely provided the insect with improved mimicry if motionless among such ferns, permitting it to avoid detection by predators. The combination of the femoral spines curved, spinulose margins to the tergal extensions would have made the overall insect rather prickly when grasped.

The new fossil provides clues into early antipredator defensive strategies and allows inferences as to the potential environment and predators, and reveals mimetic and defensive mechanisms of stick insects from 165 million years ago.

Hyaline Fibromatosis Syndrome (HFS) is a rare but severe genetic disease that affects babies, children, and adults. Hyaline, a glassy substance, accumulates in the skin and various organs, and causes painful deformities that can lead to an early death.

HFS is caused by mutation of a gene called Capillary Morphogenesis Gene 2 or CMG2. It is also abbreviated as ANTXR2 because it makes cells sensitive to anthrax infections.

In 2017, the lab of Gisou van der Goot at EPFL showed that the CMG2 protein interacts with collagen VI, regulating its concentration inside the cell. In HFS, a mutation of the CMG2 gene prevents its protein to function, leading to accumulation of collagen VI in organs.

Now, the van der Goot lab and their colleagues have followed up on the work by showing that CMG2 interacts with specific components of the cell's cytoskeleton. Publishing in Developmental Cell, the study reveals an entire network of such interactions.

Carefully "dissecting" the networks connected to CMG2, the researchers found that it binds Talin, a protein that helps connecting the key components of the cell's skeleton, integrin and actin. In this way, Talin acts as the door through which CMG2 can interact with the cytoskeleton - but only when the latter is free from any ligand.

The paper describes the process by which CMG2 releases talin "picks up" a cytoskeleton regulator called RhoA, as well as its effector proteins. The scientists identify the specific parts of CMG2 that are responsible for these interactions.

Looking at human fibroblasts, the scientists finally concluded that the way CMG2 contributes to the degradation of excessive collagen VI is by switching between Talin and RhoA. The authors write: "This explains why HFS mutations in the cytoskeleton binding domain leads to dysregulation of extracellular matrix homeostasis."

"Our findings reveal a new behavior for an extracellular matrix receptor," adds Gisou van der Goot.

Previous data from COVID-19 patients suggests that cigarette smokers are more likely to have health complications. One possible reason, researchers report May 15 in the journal Developmental Cell, is that smoking increases the gene expression of ACE2--the protein that binds SARS-CoV-2--which may promote COVID-19 infection. The study suggests that prolonged smoking could cause an increase of the ACE2 protein in the lungs, possibly resulting in a higher rate of morbidity in patients.

"Our results provide a clue as to why smokers who develop COVID-19 tend to have poor clinical outcomes," says senior author Jason Sheltzer (@JSheltzer), a cancer geneticist at Cold Spring Harbor Laboratory. "We found that smoking caused a significant increase in the expression of ACE2, the protein that SARS-CoV-2 uses to enter human cells."

ACE2, or Angiotensin Converting Enzyme 2, is a regulatory protein that has been linked to vulnerability to the 2003 SARS (2003) virus. "Evidence from mouse experiments has shown that higher levels of ACE2 make mice more susceptible to SARS," says Sheltzer. More recent work with SARS-CoV-2 found that when human ACE2 was highly expressed in mice infected with COVID-19, they died more quickly."

In humans, the lungs act as one of the primary locations of ACE2 production. To assess the direct impact of smoking on ACE2 expression in the lungs, Sheltzer compared ACE2 gene expression from the lung epithelial tissue of people who smoked cigarettes regularly to those who had never smoked. "We found that smoking caused a significant increase in the expression of ACE2," says Sheltzer, who noted that smokers produced 30%-55% more ACE2 than their non-smoking counterparts. This change was also dose dependent, with heavy smokers having the greatest ACE2 values.

The effects of smoking on ACE2 may be tied to the goblet cells in the lungs--one of the few lung cell types that Sheltzer found to actively express the ACE2 gene. "Goblet cells produce mucous to protect the respiratory tract from inhaled irritants. Thus, the increased expression of ACE2 in smokers' lungs could be a byproduct of smoking-induced secretory cell hyperplasia" says Sheltzer. An uptick in ACE2 was also associated with the inflammatory pulmonary diseases COPD and idiopathic pulmonary fibrosis.

Additionally, Sheltzer's results indicate that other viral infections, such as influenza, as well as interferon signaling--the part of the body's virus defense system--increase ACE2 expression. "Because of this, it's conceivable that SARS-CoV-2 could trigger the upregulation of its own receptor, thereby creating a positive feedback loop leading to more infections," Sheltzer says.

While the impact of cigarette smoke and ACE2 expression is compelling, it is not permanent. By comparing the lungs of current smokers to those who quit smoking for at least 12 months, Sheltzer found "a significant decrease in ACE2 expression, demonstrating that the effects of smoking on ACE2 can be reversed." Further, other studies on the effects of cigarette smoke have shown mixed results. "Cigarette smoke contains hundreds of different chemicals. It's possible that certain ingredients (like nicotine) have a different effect than whole smoke does," says Sheltzer.

And while Sheltzer finds strong support for the upregulation of ACE2 gene expression from smoking, the actual ACE2 protein may be regulated in ways not addressed in this study. "One could imagine that having more cells that express ACE2 could make it easier for SARS-CoV-2 to spread in someone's lungs, but there is still a lot more we need to explore."

Although the SARS-CoV-2 outbreak was officially presented suddenly in the popular market of exotic and wild animals in Wuhan in December 2019, phylogenetic studies state that coronavirus was already present in latency phase since October in this city in the province of Hubei. During this latency phase, the infection followed its silent course and spread among the population in a stochastic way without showing epidemic signs.

This is one of the conclusions in the article published in the journal Frontiers in Medicine by a team with the participation of the experts Jordi Serra-Cobo and Marc López, from the Faculty of Biology and the Biodiversity Research Institute (IRBio) of the University of Barcelona.

The first author of the paper is Roger Frutos, from Centre for International Cooperation in Agricultural Research for Development (CIRAD, France). Another participant in the study is Christian A. Devaux, from the French National Centre for Scientific Research (CNRS).

COVID-19: conjunction of biological and social factors

The new article goes over the conjunction of events that enabled the global spread of this new coronavirus that shows a long period of incubation, a high number of asymptomatic cases and a high international mobility.

Three conditions are necessary for an infectious disease to spread: the pathogen has to be able to infect and reproduce in humans, there must be contact between humans and the pathogen reservoir, and last, it must be spread through a social circuit. Regarding the COVID-19 -the first 4.0 pandemic according to experts- all required conditions coincided in this Chinese area in late 2019.

"The apparition of COVID-19 is the result of an exceptional 'planetary alignment', that is, a specific coincidence of biological and social factors that enabled the emergence of the new coronavirus and the spread of the global pandemic. What unchained the epidemic is the simultaneous occurrence of two major celebrations in the same place -the Chinese New Year and the Great Family Feast-, where many people who were initially infected were in contact and it provided the necessary amplification phase. Another key step was the mobility", say the authors.

Coronavirus and destruction of natural habitat: into the human species

The origin of the SARS-CoV-2 outbreak in this Asia country has been linked to wild animals (bats, pangolin cat, etc.). Moreover, the virus is thought to infect other species. "We cannot do anything to prevent the coronavirus circulation in wild state, during the sylvatic cycle", authors say.

"Environmental alterations and anthropization of natural systems have an impact on the loss of habitat and biodiversity. However, these also influence the dynamics of the pathogen reservoir species and increase the chance of infecting human species. This phenomenon is highly important in the southeast Asiatic area from where SARS and COVID-19 originated", notes lecturer Jordi Serra-Cobo, lecturer at the Department of Evolutionary Biology, Ecology and Environmental Sciences and member of the CONVAT project -promoted by the European Union for the detection of coronavirus using nanodevices.

Attention should be paid to human activities related to wild animals (trade, food, medicine, etc.) that are strongly rooted in many countries. This is why it is important to ban the use of protected species, but alternatives should be offered to avoid the impact of the wild animal black market (traditional pharmacopeia under government control, mandatory tracking and security of products and international controls, etc.).

A global threat, a local response

Even though SARS-CoV-2 occurred of a sudden in Wuhan, it should have been avoided so that some features of this first 4.0 pandemic were consistent with previous coronavirus outbreaks -for instance, the Middle East Respiratory Syndrome, MERS- known by the international scientific community.

"Other pandemics will happen. It is just a matter of probability and time. Currently, the risk of emergence is mostly coming from coronaviruses, arboviruses and influenza viruses", authors warn.

"Therefore, preparedness and education are the utmost priority. It should be an international endeavour, and it is vital for the governments to anticipate and prepare to stop the next emerging pandemic in its original place instead of just reacting and causing long-term destruction of our society and economy, which is happening now".

The EU has an ambition of being climate neutral in 2050. It is hoped that this can be achieved through a green transition in the energy sector and CO2-intensive industries, as well as through altered consumer behavior such as food habits and travel demands among the EU population.

However, should the EU implement its most ambitious decarbonization agenda, while the rest of the world continues with the status quo, non-EU nations will end up emitting more greenhouse gases, thereby significantly offsetting the reductions of EU emissions. This is the conclusion of a new policy brief prepared by economics experts at the University of Copenhagen's Department of Food and Resource Economics.

For every tonne of CO2 emissions avoided in the EU, around 61.5% of that tonne will in that case be emitted somewhere else in the world. This carbon leakage, as it is known, will result in a global CO2 savings of 385 kilos only. The policy brief is based on the conclusions of a purposely-built economic model. The model, part of the EU Horizon 2020 project EUCalc, seeks to describe various pathways to decarbonizing the EU economy.

"Obviously, the EU's own climate footprint will be significantly reduced. But the EU's economy is intertwined with the rest of the world through trade relations, which would change as we implement a green transition in our energy sector, industries and ways of life. Part of the emissions that Europe "saves" through an extensive green transition could possibly be 'leaked' to the rest of the world through, among other things, trade mechanisms, depending on the climate policy of other countries," according to economist and brief co-author Professor Wusheng Yu, of the University of Copenhagen's Department of Food and Resource Economics.

"If the world beyond the EU does not follow suit and embark on a similar green transition, the decline in global greenhouse gas emissions will effectively be limited and well below the level agreed upon in EU climate policy," adds co-author, economist and Yu's department fellow, Francesco Clora.

Less exports, more imports

In the most ambitious 2050 scenario as calculated by the EUCalc model, the EU pulls all of the green levers for production and consumption in various sectors, including the industrial and energy sectors.

In this scenario, a green transformation of CO2-intensive industries (e.g. concrete, steel and chemicals) will incur new costs for new green technologies, which in turn, will increase the price of products. This could impact the competitiveness of EU products on the global market and be advantageous to China and the United States, who would be continuing their production of similar, yet cheaper goods. The prediction is that fewer goods would then be manufactured in Europe, which would lead to an increase in new imports to satisfy consumer and commercial demand.

Similarly, a phase-out of fossil fuels by the EU would lower global demand, thus making them cheaper. In response, non-EU countries would be likely to import and consume larger quantities of fossil fuels.

Finally, more climate-friendly consumer behaviour in the EU could end up pushing part of the saved CO2 out into the rest of the world as well. For example, while a decrease in red meat consumption by Europeans may reduce imported feed grains such as soybean, it may also result in increased imports of food grains and other plant-based foods the latter of which would increase CO2 emissions in the rest of the world.

So what should the EU do?

Should Europe simply throw in the towel and drop its high ambitions for a better global climate? Certainly not. But we must make sure not to go it alone. Professor Wusheng Yu explains:

"A green transition in the EU alone cannot significantly reduce global CO2 emissions. We need to find ways to get others on board. Otherwise, the impact of our efforts will be largely offset by increased emission elsewhere, making it impossible to meet the Paris Agreement targets in time."

Therefore, Professor Yu says that it is essential for the EU to formulate green strategies for each sector and every member state, while taking these economic mechanisms into account and carefully evaluating their impact, when it comes to encouraging other countries to pursue similar decarbonization strategies.

FACTS:

If the EU implements a very ambitious climate strategy while the rest of the world maintains the status quo, the EU-Calc model forecasts a CO2 leakage of about 61.5%. This means that for every tonne of CO2 that the EU ceases to emit, the rest of the world will increase emissions by 615 kilos of CO2. The calculation is based on average CO2 emissions in EU countries.

Read the brief, 'Implications of decarbonizing the EU economy on trade flows and carbon leakages', here

The results are generated from a purpose-built economic model fed with detailed data collected from a wide range of sectors in all EU member states, plus the UK and Switzerland.

The EUCalc project aims to describe various pathways towards a green transition in the EU. In addition to the open source model (including the economic module), the project has developed a web tool where users can calculate CO2 emissions themselves according to different scenarios.

EUCalc is a partnership among 12 institutions located in 9 European countries and funded by the EU Horizon 2020 programme.

A new paper in The Review of Economic Studies, published by Oxford University Press, finds that people who use a coin toss to decide on an important change are more likely to follow through with that decision, are more satisfied with that decision, and report a higher overall happiness after a six month period.

Every person faces difficult decisions with potentially life-changing consequences: whether to quit a job, seek more education, end a relationship, quit smoking, etc. While behavioural economics offers several decision-making models, from "prospect theory" to "the sunk cost fallacy," it has little to say about people's overall happiness with their choices after they make important decisions.

To investigate this, University of Chicago economist Steven Levitt created a website (Freakonomics Experiments) where subjects answered a series of questions. Some examples of questions asked by Levitt, the co-author of Freakonomics and several other books, were: Should I quit my job? Should I move? Should I propose? Should I adopt? Users were also invited to create their own questions, including Should I get a tattoo? Should I try online dating? Should I rent or buy?

One choice, either the affirmative or the negative, was then assigned to heads and the other assigned to tails. Prior to the coin flip, the subjects were encouraged to identify a third party to verify their outcomes. Both the initial coin-flipper and the third parties received a follow up survey after two-months and six-months.

The two-month survey found that participants favoured the status quo, making a change less frequently than they predicted they would before the coin toss. At the six-month survey, this bias toward the status quo was gone. Furthermore, those who were instructed by the coin toss to switch their current position were more likely to actually make the change, reported that they were substantially happier, and said that they were more likely to make the same decision if they were to choose again. This was true for virtually every question at both the two- and six-month surveys. These results are inconsistent with the conventional theory of choice. In such theory, people who are on the margins should, on average, report equal happiness regardless of which decision they made.

'Society teaches us "quitters never win and winners never quit," but in reality the data from my experiment suggests we would all be better off if we did more quitting', said author Steven Levitt. 'A good rule of thumb in decision making is, whenever you cannot decide what you should do, choose the action that represents a change, rather than continuing the status quo.'