Culture

Profs. Okujima and Uno at Ehime University, in collaboration with Prof. Kobayashi at Shinshu University, reported the selective synthesis, the molecular structure, optical properties and electronic structure of cyclo[9]pyrrole, a ring-expanded porphyrin consisting of directly connected pyrrole rings.

Porphyrins, which are well-known natural porphyrin molecules, e.g. heme and chlorophyll, are attractive for use in practical materials because of the easy optimization of their optical and physical properties by conjugation expansion and functionalization. In 2002, Sessler reported the first synthesis of cyclo[n]pyrrole (n: the number of pyrrole rings). Peripheral alkyl-substituted cyclo[8]pyrroles were obtained via an oxidative coupling of 2,2'-bipyrrole, and showed an intense L band at ca. 1,100 nm.

We successfully synthesized a good yield of cyclo[9]pyrroles via the oxidative coupling of terpyrrole. A relatively distorted structure with a C2-like symmetry was clarified by NMR and X-ray diffraction analyses. Intense absorption was observed at ca. 1,740 nm. We analyzed the optical and electronic structures using magnetic circular dichroism spectroscopy and time-dependent density functional theory calculations. Comparison of cyclo[8], [9], and [10]pyrroles showed the electronic structures don't significantly depend on the number of pyrroles.

The Earth is a sphere, and it comprises spheres: atmosphere, hydrosphere, cryosphere, lithosphere and biosphere -- in short, all of the cycles that interact to influence Earth's weather and climate. Now, to better research how the spheres interact and impact the planet, China is launching EarthLab in Beijing. On June 23, after EarthLab's opening ceremony, researchers will begin trials to demonstrate the facility's ability to integrate simulations and observations to more accurately project outcomes and provide a scientific foundation to predict and mitigate such things as natural weather disasters.

EarthLab's research team published an introduction to the facility on June 23 in Advances in Atmospheric Sciences.

"Since the earth system is extremely large and complex, traditional theories and observations are too limited to meet the overall requirements of the scientific research community," said paper corresponding author He Zhang, EarthLab researcher affiliated with the Institute of Atmospheric Physics (IAP) at the Chinese Academy of Sciences (CAS). "EarthLab is the first comprehensive virtual earth laboratory in China for simulation the physical climate system, environmental system, ecological system, solid earth system, and space weather system as a whole with a high-performance scientific computing platform."

In partnership with Tsinghua University, IAP/CAS began construction of EarthLab in 2018. After successful trialing, inspections and approvals, EarthLab is expected to become fully operational -- and open to universities and research institutes across the world -- in 2022.

"Other countries, such as the United States and Japan, as well as some European countries, have built specialized numerical simulations facilities," Zhang said, noting that China's vast and complex topography has been difficult to model accurately with various levels of observational and experimental resources across the country. "Weather, climate and environmental disasters occur frequently and seriously with grave losses of life and property. Consequently, a global earth system simulation system, as well as high-precision regional environmental simulation system, are urgently needed to better predict climate and environment variability, to prevent and mitigate natural disasters more effectively, and to formulate relevant national plans more scientifically."

According to Zhang, EarthLab will also become a science outreach base for children and students to learn more about Earth sciences. During an IAP outreach day in 2017, children voted on EarthLab's Chinese name: Huan. The name means "a place as vast as the earth where people live and upon whose land they depend".

"Our ultimate goal is to predict Earth systems on a vast range of time scale, from seconds to hundreds of years, and of spatial scale, from 10 meters to millions of meters," Zhang said. "Along with other earth simulators around the world, the development and construction of EarthLab will advance not only the understanding of the Earth's spheres and their interactions, and Earth's past, present and future, but also the progress of computational mathematics, high-performance computing and technology, and other broader fields."

A paper published in the prestigious journal Nature Medicine on long-COVID, describes persistent symptoms six months after acute COVID-19, even in young home isolated people.

The study from the Bergen COVID-19 Research Group followed infected patients during the first pandemic wave in Bergen Norway.

"The main novel finding is that more than fifty per cent of young adults up to 30 years old, isolated at home, still have persistent symptoms six months after mild to moderate disease", the leader of the group, Professor Nina Langeland explains.

The most common symptoms were loss of smell and/or taste, fatigue, shortness of breath, impaired concentration, and memory problems.

"There was a significant correlation between high antibody levels and symptoms in home isolated patients, other risk factors for symptoms were asthma or other chronic lung disease", says Professor Rebecca Cox, Head of the Influenza Centre at University of Bergen and Haukeland University Hospital and co-leader of the research group.

Impaired memory and concentration difficulties

In non-hospitalized COVID-19-patients, thirty per cent experienced fatigue which was the most common symptom. Children under the age of 16 years had fewer long-term symptoms than adults, but Associate Professor Bjørn Blomberg, and first author of the article, underlines:

"The cognitive symptoms of impaired memory and concentration difficulties are particularly worrying for young people at school or university and highlights the importance of vaccination to prevent the long-term health implications of COVID-19".

A rare genetic defect that affects the so-called ALG2 gene can cause serious metabolic diseases in humans. It does so through the defective formation of proteins and sugar molecules. Until now, its rareness and complexity made it difficult to study this congenital glycosylation disorder. A research team led by Prof. Dr Joachim Wittbrodt and Dr Thomas Thumberger from the Centre for Organismal Studies (COS) of Heidelberg University has finally succeeded in introducing the underlying mutation in the ALG2 gene in a fish model, thus allowing the causes of these complex diseases to be studied at the molecular level.

Human cells are kept alive by the activity of millions of proteins. As they mature, these proteins must be modified in a myriad of ways, such as through the addition of sugar molecules - a crucial change for proper function. Defects in this sugar-adding process, also known as sugar decoration, are often lethal at the very early stages of development. As Prof. Wittbrodt explains, in rare cases a genetic defect causes sugar-addition deficiencies, which then manifest as congenital disorders of glycosylation. "Correct protein glycosylation requires a number of enzymes functioning together like clockwork," states the researcher. The ALG2 gene has an especially important task in this process. It codes an enzyme needed for the correct branching of the sugar chain. If this process is disturbed, patients appear unaffected at birth but develop problems in different organs, such as the eyes, brain, and muscles, during early childhood.

The team led by Prof. Wittbrodt and Dr Thumberger used the CRISPR/Cas9 gene editing scissors to introduce an ALG2 mutation in a fish model, the Japanese rice fish or medaka. "Fish are particularly good models for these disorders because they develop outside the mother, making them very suitable for studying early embryonic defects," explains Dr Thumberger. In addition, the genome of the Japanese rice fish can be edited efficiently and precisely. "Our fish are genetic twins, so to speak, so the effect of individual changes can be directly identified as compared to non-genetically altered fish."

Although the evolutionary distance between humans and fish is vast, the researchers report many of the same symptoms in the fish model that appear in ALG2 patients, including specific neuronal defects. They were surprised by the results yielded by the analysis of the total medaka organism, which took into account the full spectrum of different cell types. "Although all cells of the fish showed the same reduced ALG2 activity, some cell types were more affected than others," states Prof. Wittbrodt. In the retina of the fish eye, cone cells needed for colour-sensing were unaffected, but there was a progressive loss of rod cells needed for vision in low light, thus rendering the fish night-blind. Now the researchers hope to identify the proteins that cause the rod cells to die off because of diminished sugar binding.

"Our studies on the medaka fish model showed that all symptoms could be prevented by supplying fully functional ALG2 mRNA - the blueprint for producing the correct ALG2 enzyme. We were able to effectively reverse the genetic defect in the fish model. That means that we can now systematically analyse the individual function areas of the ALG2 enzyme. We are particularly interested in the cell type-specific response in the context of the whole organism," stresses Joachim Wittbrodt. Building on this research, the Heidelberg research team plans to study the molecular mechanisms and causes for the development of such complex metabolic diseases in humans.

Several eye clinics around Sweden are seeing a rise in eye damage related to the racket sport padel. In an article in the Journal of the Swedish Medical Association (Läkartidningen), eye researchers affiliated with the University of Gothenburg state that padel is a potential high-risk sport for eye injuries, and that wearing protective goggles is a good idea.

Ball sports are often associated with an increased risk of eye injuries, and the risk seems to be even greater with padel, a sport that is now highly popular in Sweden (and should not be confused with the North American "paddle tennis").

"The ball has a weight of about 50 grams, and a size corresponding to the opening of the eye socket. The ball speed is high, and for a smash shot can be up to 130 kilometers an hour. The bouncing properties of the ball also make recoil assessments quite difficult, which probably increases the risk of the eyes getting damaged," says Gunnar Jakobsson, ophthalmologist at the University of Gothenburg and chief physician at the eye clinic (Department of Ophthalmology) at Sahlgrenska University Hospital.

Serious injuries are rare

Most eye injuries that occur in padel, such as minor hemorrhages inside the eye that require no surgery, are relatively mild. But there have also been reports of occasional serious cases in which padel players suffer lasting visual impairment. In the event of severe injury, there is even a risk of blindness. In the article in the Journal of the Swedish Medical Association (Läkartidningen), Jakobsson and his colleague Catharina Thörnland describe three cases of people incurring eye damage while playing padel. Although their injuries were moderate, they all needed surgical treatment to get better.

Protecting the eyes

Since padel is a potentially high-risk sport where eye injuries are concerned, it is a good idea to wear goggles while playing. Several scientific studies show that wearing goggles, or some other means of eye protection such as a safety visor or face shield, is the most effective way to avoid eye injuries in risky sports. If these protective devices are used correctly, the risk of eye damage is reduced by up to 90 percent.

Jakobsson draws a parallel to floorball, another modern sport characterized by a rapid rise in popularity -- for floorball, that occurred in the 1990s.

"For a while, floorball became the sport that caused the most eye injuries. Thanks to the introduction of mandatory goggles for children and at junior level, and strong recommendations for senior players, eye damage among floorball players has declined."

A sensitive blood test being developed by a team of researchers at the University of Michigan Rogel Cancer Center shows promise for predicting whether patients with metastatic HPV-positive throat cancer will respond to treatment months earlier than standard imaging scans.

That's according to a study, published in Oncotarget, validating the test in a small group of patients with metastatic human papillomavirus-related oropharyngeal squamous cell carcinoma -- a type of head and neck cancer that develops in the back of the mouth and in the throat.

If the test can quickly determine that a treatment approach isn't helping, it could allow doctors to seek out alternative therapies or clinical trials in a more timely manner. It could also potentially spare some patients months of toxic side effects from a treatment that isn't working.

"Currently, the only way doctors know if a treatment is working is for the patient to get an imaging scan every few months to see whether their tumors are shrinking," said oncologist Paul Swiecicki, M.D., one of the study's senior authors. "And this isn't fully accurate since some cancers show what we call pseudoprogression, where a successful treatment actually makes the tumors bigger before it shrinks them.

"Our goal was to develop a test that could tell us whether a treatment is likely to work after a single cycle," he continued.

The research comes amid a rising incidence of throat cancer caused by human papillomavirus infections, which are often spread through sexual activity. Once the cancer has recurred or spread within the body, patients typically only live for about one year. Furthermore, most of the available treatments, such as immunotherapy, work for less than 20% of patients and can have significant side effects.

The test is a form of "liquid biopsy" that looks for DNA shed by a patient's cancer cells into their bloodstream using a method known as digital droplet PCR, which can amplify minute amounts of DNA for analysis.

Development of the test was led by co-first authors Catherine Haring, M.D., an otolaryngology resident, and Chandan Bhambhani, Ph.D., a postdoctoral research fellow in the lab of senior study author Muneesh Tewari, M.D., Ph.D.

"We can actually identify DNA from a small tumor at the back of the throat circulating throughout the entire bloodstream," Haring said.

"From a single tube of blood, this technology can isolate a single copy of tumor DNA," Bhambhani added. "And quantifying the number of copies can tell us whether a patient's cancer is responding to treatment."

The study analyzed more than 100 samples taken over nearly two years from 16 patients with advanced cancer that was positive for HPV 16, one of the most common, high-risk types of HPV infection. Seven of the patients were treated with immunotherapy regimens. Eleven patients underwent treatment that included chemotherapy.

The researchers found that increasing levels of HPV-positive circulating tumor DNA after a course of treatment were a strong indicator that the cancer was not responding to the treatment. And that the tumor DNA could be detected months ahead of tumor growth that can be measured on imaging scans.

Swiecicki points to one of the patients in the study as an example.

The patient underwent chemotherapy treatment for about 200 days. Their HPV 16-positive circulating tumor DNA fell to nearly zero for the first 100 days and imaging scans showed the disease had stabilized. But copies of the HPV 16 DNA started to multiply in their blood between day 100 and day 200, when the disease progression was ultimately detected on imaging scans.

"In the future, the idea is that the test would give us a window of time -- about 100 days in this example -- to find alternative therapies or a clinical trial," Swiecicki said. "And this particular patient did have significant toxicities from the therapy, some of which potentially could have been avoided once it became clear the cancer was no longer responding to the treatment."

Senior study author Chad Brenner, Ph.D., an associate professor in the Department of Otolaryngology-Head and Neck Surgery, notes that scientists around the world have been working to develop similar tests. The success at U-M was the result of collaboration that involved clinicians as well as researchers with expertise in next-generation sequencing and in the genetics of head and neck cancer.

"Everybody talks about team science," added Tewari, a professor of internal medicine and of biomedical engineering, "but everybody involved in this effort contributed a unique piece. And U-M is a place that really embraces this spirit of interdisciplinary collaboration."

The blood test may also be useful for early detection of recurrence before the cancer is incurable. According to additional findings the research team recently described in the journal Oral Oncology, HPV circulating tumor DNA is in the blood of patients with early stage throat cancer. Retrospectively, the test was also able to identify recurrent disease in a patient more than a year before it was detected by with standard approaches.

Before treatment, the patient had significant levels of circulating tumor DNA in their blood, which dropped down to near zero in the months following treatment.

"We thought they were potentially cured," Brenner said. "We couldn't detect this biomarker at all."

But after six months, the level of circulating tumor DNA in their blood started to rise -- slowly at first and then more dramatically.

"Yet we weren't able to detect clinical signs of recurrence until after the two-year time point," Brenner noted. "So, our test was able to detect the first signals of recurrence a year and a half before it was evident on imaging scans."

While work to further optimize and validate the test continues, the team is partnering with other academic medical institutions to use the test to study the relationship between HPV-positive circulating tumor DNA and clinical outcomes in additional patients.

Pairing blueberry pie with a scoop of ice cream is a nice summer treat. Aside from being tasty, this combination might also help people take up more of the "superfruit's" nutrients, such as anthocyanins. Researchers reporting in ACS' Journal of Agricultural and Food Chemistry show that α-casein, a protein found in cow's milk, helped rats absorb more blueberry anthocyanins and their byproducts, boosting accessibility to these good-for-you nutrients.

In studies, anthocyanins have been shown to have antioxidant properties, lower blood pressure and reduce the risk of developing some cancers. However, only small amounts of these nutrients are absorbed from blueberries during digestion, despite their abundance in the fruit. Previous researchers have reported that consuming foods with ingredients such as citrus pectin, capcasin, capsicate and some proteins improve the uptake of anthocyanins. For instance, Bin Li and colleagues found that α-casein and β-casein proteins from cow's milk protected blueberry anthocyanins in simulated digestion experiments. Now, this team wanted to see whether α-casein could help increase the absorption of blueberry anthocyanins in vivo.

The researchers fed rats purified blueberry anthocyanin extracts, adding α-casein to the solution given to one group of rats. During the next 24 hours, anthocyanin and metabolite concentrations were 1.5 to 10.1 times higher in the α-casein group than in the control rats. When examining α-casein's molecular structure, the researchers observed that its amino acids allowed it to interact with and encapsulate the anthocyanin molecules, improving their stability in the intestines and allowing for better transport into the bloodstream. While the α-casein protein used in these experiments was derived and purified from milk, the results may not be the same for whole milk because its fats and sugars could impact absorption, the researchers explain. They say their next step is to conduct similar tests with human subjects.

For patients who have inflammatory bowel syndrome (IBS), the condition is literally a pain in the gut. Chronic -- or long-term -- abdominal pain is common, and there are currently no effective treatment options for this debilitating symptom. In a new study in ACS Pharmacology & Translational Science, researchers identify a new potential source of relief: a molecule derived from spider venom. In experiments with mice, they found that one dose could stop symptoms associated with IBS pain.

The sensation of pain originates in electrical signals carried from the body to the brain by cells called neurons. Tiny channels in the surfaces of neurons help them transmit these signals by allowing positively charged sodium ions to pass into the cell. There are numerous types of sodium channels, and some pain-killing drugs work by blocking them. However, existing treatments interfere with channels indiscriminately and can only be used briefly -- not for chronic pain. Stuart Brierley, Glenn King and colleagues wanted to find a way to selectively target the channels activated during chronic IBS pain.

The researchers focused on a particular sodium channel they suspected was responsible for chronic IBS pain. Then, to block it, they turned to the richest known source of molecules that alter the activity of sodium channels: spider venom. In the venom of a Peruvian tarantula, they discovered a molecule that they named Tsp1a, which had promising blocking activity. To test its potential as a treatment, the researchers used mice that had an IBS-related condition, and they monitored the mice during the experiment to detect a reflex associated with pain. A single Tsp1a treatment delivered into the mice's colons significantly reduced the occurrence of this reflex, indicating pain relief. What's more, Tsp1a appeared highly selective and did not interfere with other body functions, suggesting it could be used safely in humans. While Tsp1a shows promise as a potential treatment for chronic IBS pain, thorough studies of its activity in the body and the immune system's reaction to it will be critical, the researchers write.

Air quality varies greatly within regions and cities around the world, and exposure to air pollution can have severe health impacts. In the U.S., people of color are disproportionately exposed to poor air quality. A cover story in Chemical & Engineering News, the weekly newsmagazine of the American Chemical Society, highlights how scientists and community activists are using new technologies to gather data that could help address this inequity.

Despite the success of the U.S. Clean Air Act in improving ambient air quality over the past 50 years, discriminatory housing, loan and other policies -- known as redlining -- have limited where people of color can live. That means they are more likely to live near "pollution hot spots," such as warehouses, freeways and ports, writes Senior Correspondent Katherine Bourzac. As a result, communities of color have a higher risk of developing cardiovascular disease, asthma and other health issues. Although regulatory air monitors are being operated by federal and local agencies, they typically can't capture air-quality differences within cities.

To fill the gaps, researchers are combining air-pollution measurement technologies with land-use data, modeling studies and other data collection methods. For example, scientists studying air quality in Houston using satellites and U.S. Census Bureau data determined that majority Black, Hispanic and Latino neighborhoods had 37% higher levels of nitrogen dioxide than majority white communities. Scientists hope that higher resolution data from satellites and ground-based tools will help policymakers mitigate inequity and adverse health effects due to air pollution.

Previous research was falsely reassuring; captured only 2% of cirrhosis patients

Findings underscore lack of access to health care for Black patients

Cirrhosis is leading cause of death and affects more than 600,000 people in U.S.

CHICAGO --- Black patients with cirrhosis - late-stage liver disease - are about 25% more likely to die compared to non-Hispanic white patients and four times less likely to receive a liver transplant, reports a new Northwestern Medicine study.

Estimates of racial disparity in cirrhosis have been limited by a lack of large-scale longitudinal data, which track patients from diagnosis to death and/or transplant.

The paper is one of the first to link all seven large liver centers in Chicago with the death registry and transplant registry to examine racial disparities in cirrhosis on a population level. Previous surveillance of outcomes by race has been through the transplant registry alone, which only captures about 2% of those with cirrhosis, and therefore does not lend itself to understand the true disparity affecting patients with cirrhosis.

"The findings underscore broader societal issues of access to health care for our Black patients," said senior study author Dr. Daniela Ladner, professor of surgery at Northwestern University Feinberg School of Medicine and a Northwestern Medicine transplant surgeon. "We need to support our Black community to find the way to optimal care, including offering transplants at the same rate as all other patients."

The study did not examine the cause of the disparity, but other research has shown the reasons are a combination of structural (lack of resources such as medical specialists, pharmacies, transportation, safe housing) and institutional (policies and practices that disadvantage or prioritize certain groups over others).

The paper was published recently in Hepatology.

Cirrhosis is a common disease thought to affect more than 600,000 people in the U.S. and is a leading cause of death in adults. It is caused by chronic viral infections of the liver (hepatitis B and hepatitis c), fatty liver disease and alcohol use disorder.

Previous research has addressed the small group of patients who are listed for liver transplant (

"The findings from this study should prompt quality initiatives at each of the liver centers in this study to examine what barriers to care are contributing the most to the disparities we found," said co-lead author Dr. Nikhilesh Mazumder, a Northwestern Medicine transplant hepatology fellow. "Further research is needed to verify these results on a national level, so we can address this disparity nationwide."

One remedy, the authors said, is targeted interventions to facilitate health care access for Black patients such as the African American Transplant Access Program at Northwestern Medicine. This program is directed by transplant surgeon and co-lead author Dr. Dinee Simpson, assistant professor of surgery at Feinberg and a Northwestern Medicine transplant surgeon.

"We must recognize that health equity is not attainable for everyone if we treat them the same, because different groups face different barriers," Simpson said. "We must research the barriers our Black patients face and be willing to address them with creative solutions. This must happen at the institutional level and the structural level for better health to be realized in this community."

Among patients listed for liver transplants, there were no differences among patient outcomes, the study found.

It is also important to continue to study Black disparities to find the best solutions to resolve them, the authors said. Population-based cohorts such as the Chicago Area Patient-Centered Outcomes Research Network, spearheaded by co-author Dr. Abel Kho, that combine electronic health records from 10 health care systems, allow for these population-based studies.

BUFFALO, N.Y. -- The giant plumose anemone is an animal, but it looks a bit like an underwater cauliflower. Its body consists of a stalk-like column that attaches to rocks and other surfaces on one end, and to a crown of tentacles on the other.

The anemones use these feelers to collect and shove food into their mouths, and a new study provides an in-depth look into the rich diversity of prey the anemones are catching. This includes a surprising menu item: ants, specifically the pale-legged field ant, Lasius pallitarsis. And the occasional spider.

The research was published on June 15 in the journal Environmental DNA. The study focused on giant plumose anemones, known to scientists as Metridium farcimen, that were fixed to the sides and undersides of floating docks in the region of the San Juan Archipelago in the northwestern part of the state of Washington.

The team used a method called DNA metabarcoding to identify the gut contents of a dozen giant plumose anemones. The species' diet was heavy on arthropods, especially crabs (presumably larvae, researchers say), and also included barnacles (larvae or molts), copepods and insects.

"We've greatly expanded the list of things we know that they eat. They're eating whatever they can catch, whatever isn't too big or too small, whatever can't swim away," says first author Christopher Wells, PhD, a postdoctoral researcher in the University at Buffalo Department of Geology. "One of the most surprising results is that in addition to all the usual suspects you'd find in marine plankton, we also found that a part of the diet, about 10% at the time of the study, consisted of ants, which are not marine."

By digging into the natural history of the pale-legged field ant, the researchers came up with a possible explanation for how these ants became part of the marine food chain.

"It's timed with the reproductive portion of the lifespan," Wells says, noting that the study was conducted during the month of August, when the ants have mating flights. "They produce winged queens and drones, which mate and make new colonies. They're not strong fliers and the wind pushes them around, potentially into the water."

The team's results indicate that giant plumose anemones also eat the occasional hapless spider, along with a few insects in addition to ants that may wander too close to the water's edge and drown.

The study was a collaboration between Wells; Gustav Paulay, PhD, at the Florida Museum of Natural History; Bryan Nguyen, PhD, at George Washington University; and Matthieu Leray, PhD, at the Smithsonian Tropical Research Institute. Wells, now in the Department of Geology in the UB College of Arts and Sciences, conducted the research at Friday Harbor Laboratories while completing a PhD at the University of Washington.

By extracting genetic material from a slushy mix of partially digested food, the researchers were able to work backward, comparing their results to information stored in databases about the DNA of varied organisms.

"Part of our research was using this method, DNA metabarcoding, and comparing it to traditional techniques where you wash out or cut open an anemone and then identify what you can see. The trouble is when you do that, you can't identify everything," Wells says. "You might say, 'That looks like it's a copepod antenna,' but you can't tell what species it is.

With DNA metabarcoding, you can identify what species' antennae that is. We were able to identify a lot more diversity using metabarcoding."

Knowing what an animal eats is indispensable when trying to understand how marine communities function.

"When a plankton community floats overtop a bed of anemones, the plankton is filtered by millions of grasping tentacles," Wells says. "This can drastically change the composition of the plankton community, which is food for many economically important animals such as bivalves and fish."

Anemones found in close proximity to one another had varied diets, but, "I don't think that's because they're choosing different things to eat," Wells says. "They eat what they can, and it's very patchy what they get, depending on what's there."

While the researchers were able to identify many of the species preyed on by the giant plumose anemone, Paulay, curator of invertebrate zoology at the Florida Museum of Natural History, noted they were unable to match a substantial portion of DNA sequences with any known organisms, underscoring how much is left to be discovered in the oceans.

How long do virus-laden particles persist in an elevator after a person infected with COVID-19 leaves? And is there a way to detect those particles? A group of electrical engineers and computer scientists at KAUST set out to answer these questions using mathematical fluid dynamics equations.

"We found1 that virus-laden particles can still be detected several minutes after a short elevator trip by an infected person," says KAUST electrical engineer Osama Amin.

The team's equations and breath simulations suggest that a biosensor's ability to detect a virus improves when placed on an elevator wall that can reflect particles. Also, to protect future occupants, the amount of particles in the air can be reduced by making the other three walls absorptive.

Amin and his colleagues at KAUST have been working on developing a nontraditional communication concept called "communication via breath." The concept2 models chemical and biological molecules emitted in exhaled breath as if they are information carriers in a communication system that can be detected on the other end by a "receiver," in this case a biosensor.

"This kind of study requires input from researchers with varied expertise in theoretical channel modeling, system design and integration, and machine learning schemes," says Amin.

In their previous work, they used equations to understand how exhaled molecules disperse in open spaces3. They also proposed4 a sensing system that can detect molecules exhaled from people's breath at mass gatherings.

In their current work, they developed a model and simulations that describe what happens to molecules exhaled in breath within a closed room over space and time. Their modeling took into consideration the abilities of walls to absorb or reflect particles. Once their models were able to describe, solve and simulate virus-laden particle concentration in a small room over space and time, the researchers worked on calculating the probability of a biosensor being able to detect those particles.

The calculations assumed the deployment of a biosensor that uses antibodies to bind to a specific virus and initiate a signal. They also accounted for parameters such as aerosol sampling time and volume, sampling efficiency and the probability of the antibodies binding to a virus.

"Our study provides vital mathematical and simulation gears for our leading research on communication via breath, which we hope will be used for more analyses and system designs," says KAUST computer scientist Basem Shihada.

The team is now developing an aerosol sampling and detection prototype for organic chemicals exhaled in breath. "We also plan on proposing mechanisms that reduce the probability of infection in small spaces, including ventilation mechanisms, periodical air sanitization and the design of absorptive and reflective walls," says Shihada.

Researchers from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences have discovered a 120-million-year-old partial fossil skeleton of a tiny extinct bird that fits in the palm of the hand and preserves a unique skull with a mix of dinosaurian and bird features.

The two-centimeter-long (0.75 inch) skull of the fossil shares many structural and functional features with the gigantic Tyrannosaurus rex, indicating that early birds kept many features of their dinosaurian ancestors and their skulls functioned much like those of dinosaurs rather than living birds.

Their findings were published in Nature Communications on June 23.

The bird was deposited 120 million years ago in a shallow lake in what is today Liaoning Province in northeastern China.

Through detailed reconstruction of the bird family tree, the researchers demonstrated that the new fossil bird species belongs to an extinct group of birds called enantiornithines, or "opposite birds." They are the most diverse group of birds from the time of the dinosaurs in the Cretaceous and have been found all over the world.

In living birds, the quadrate is one of the most movable bones in the skull and allows for the unique feature of living birds known as "kinetic skull," which allows the upper jaw to move independently of the brain and the lower jaw.

In contrast with living birds, however, the skull of this new "opposite bird", as well as those of dinosaurs like Tyrannosaurus rex and the close dinosaurian relatives of birds (e.g., troodontids and dromaeosaurs), is not kinetic. Instead, its bones are "locked up" and unable to move.

The temporal regions (sides) of the skull of this bird fossil are very different from living birds. This new species has two bony arches for jaw muscle attachment like those found in reptiles such as lizards, alligators, and dinosaurs, making the rear of the skull rigid and resistant to movement among the bones.

"When reconstructing all parts of the skull three-dimensionally from the high resolution CT scans of the fossil, I had a problem figuring out one bone in particular," said Dr. WANG Min, the lead and corresponding author of the study. He said his colleague Dr. Thomas Stidham proposed that the bone was the pterygoid and looked "exactly like that of the dromaeosaur Linheraptor." The fossil has the first well-preserved pterygoid bone found in an early bird.

The researchers compared CT scans of the bird skull to scans of the skull of the well-known dromaeosaur Linheraptor from Inner Mongolia, China. The results showed that many other features of the rear portion of the skull, including the shape of the basisphenoid bone and its connections with other skull bones, also resemble dromaeosaurs rather than living birds.

"The fossil bird and dinosaurs also lack the discrete contact between the pterygoid and quadrate near the palate that is used in skull kinesis in living birds. In combination with the 'locked up' temporal bones, the difference in the palate structure also points to the absence of kinesis among early birds," said Dr. Stidham, co-author of the study.

Furthermore, the team's discovery and meticulous anatomical research help to reinforce the already well-supported contention, based on many different lines of evidence, that birds are not only living dinosaurs, but evolved from the branch of dinosaurs that includes troodontids and dromaeosaurs like the "four-winged" Microraptor and swift Velociraptor.

"Having a 'dinosaur' skull on a bird body certainly did not stop the enantiornithines, or other early birds, from being highly successful in places all around the world for tens of millions of years during the Cretaceous," said Dr. WANG.

The stink of ammonia in urine, sweat, and rotting meat repels humans, but many insects find ammonia alluring. Now, UConn researchers have figured out how the annoying insects smell it, a discovery that could lead to better ways to make them buzz off.

The sense of smell is enormously important. Mammals devote a third of their genetic code to odor receptors found in the nose, and have more than 1,000 different kinds that allow us to smell an estimated trillion different odors.

Flies don't have noses. Instead, they smell with their antenna. Each antenna is covered with tiny hairs called sensilla. Each sensilla contains a few neurons--fly brain cells. Each neuron expresses one type of odor receptor, and they all fall into two main classes. Or so scientists thought.

But recent work by UConn neuroscientist Karen Menuz and her colleagues, reported online in June in Current Biology, identified a new type of odor neuron devoted to sniffing ammonia. And the receptor it uses is unlike any other odor receptor known.

Flies and other insects use the scent of ammonia to find food sources. Mosquitoes find humans to bite by following the faint scent of ammonia in our sweat, along with other clues. Many crop pests do the same, locating fruit and agricultural products to infest and consume.
"When an odor binds to a receptor, the cell depolarizes, and sends a signal saying 'hey, the odor is here!' Insects are small, and odors come in plumes, so most insects will fly straight as long as the concentration is the same or growing. If they lose the odor plume, they'll do a casting behavior, flying in zig zags to find it," Menuz says.

Knowing exactly how the insects smell ammonia might yield effective ways to block them from following that scent plume--and from finding us and our crops.

But figuring out exactly how and what a fly smells is tricky. Menuz and her colleagues are able to gently hold a fly down and use incredibly fine pieces of glass to probe individual neurons in sensilla on the fly's antenna. Then they let the ammonia waft.

They probed all three types of scent neurons in the flies' sensilla, but they didn't respond to ammonia. But the fly was obviously smelling it. So the researchers realized there had to be a fourth scent neuron they hadn't known was there. And they found it--but it didn't seem to have the usual odor receptors on it. It was covered in ammonia transporter (Amt) a molecule that is known to allow ammonia in and out of cells.

No one had ever known a transporter molecule to also act as an odor receptor. But there it was. When they selectively killed off only that type of neuron, the flies did not respond to ammonia at all. And when the team forced scent neurons that don't normally respond to ammonia to express Amt on their surfaces, those neurons began responding to ammonia, too.

The team hopes to learn whether mosquitoes use the same system to smell ammonia. If it's used by both mosquitoes and flies, it's a good bet the Amt receptor-as-sniffer is used by all insects, and developing ways to block Amt could be an effective way to protect people and crops from pests attracted to ammonia.

A new biocompatible polymer-based composite material could soon replace metal plates in treating difficult and unstable fractures. Developed at KTH Royal Institute of Technology in Stockholm, the newly-developed material is as strong as dental composites yet non-toxic.

The material and a surgical method, which were published in Advanced Functional Materials, will be used in clinical studies in 2023 and 2024, with a focus on hand fractures.

Michael Malkoch, professor of fibre and polymer technology at KTH, says that the material and method, AdhFix, will enable customized plating for fixation of fractures with a more comfortable, less complicated recovery. Collarbone and rib fractures in particular are ideally suited for the proposed treatment, since such injuries are not easy to stabilize.

Metal plates cannot be easily customized in shape, and they tend to adhere to soft tissue, resulting in debilitating complications, says Malkoch. For example, researchers in the U.S. have found that nearly 64 percent of finger fractures treated with metal plates result in mobility complications.

The alternative surgical method, AdhFix, combines screws with a build-up of the polymer/hydroxyapatite composite instead. The composite is shaped in situ before being rapidly cured on demand via high-energy visible-light-induced thiol-ene coupling chemistry.

Evaluations on human cadaver hands with proximal phalanx fractures show that AdhFix withstands the forces from finger flexing exercises. In models of in vivo femur fractures in rats, the methodology supported bone healing without degradation, adverse effects or soft-tissue adhesions.

"No fracture is the same as the other, this is one of the absolute advantages of the material," says Malkoch. "A surgeon can tailor the fixation plate according to the patient's bone shape and the structure of the fracture. The hospital also does not have to store metal plates."

Malkoch says the material and method also may be applied to veterinary care as well. Animals with metal plates are known to avoid going outdoors in cool temperatures because the metal conducts the cold differently than the KTH researchers' composite.