The worldwide proliferation of energy efficient broad spectrum lighting has the potential to disrupt an array of visually guided ecological processes.

New research has demonstrated that these new lighting technologies can significantly improve a predator’s ability to discriminate prey species against a natural background.

The magnitude of this effect varies depending on an organism’s colour, meaning certain colour variations may be at greater risk.

The study, published in the Journal of Applied Ecology, was conducted by researchers at the University of Plymouth and Plymouth Marine Laboratory (PML).

It is one of the first to examine the potential for artificial light at night (ALAN) to affect the camouflage mechanisms of coastal species.

Oak McMahon, who led the research while studying for an MSc in Applied Marine Science and is now a PhD candidate at the University of Plymouth, said: “This study clearly indicates that new lighting technologies will increase the conspicuousness of prey species by reducing the efficacy of their camouflage. Our findings revealed that species of Littorinid snails found commonly on our coastlines will remain camouflaged when illuminated by older style lighting. However, when illuminated by modern broad spectrum lighting, they are clearly visible to predators and at far greater long-term risk as a result.”

Funded by the Natural Environment Research Council, this is the latest research by the University and PML to highlight the growing levels of ALAN and its impacts on coastal environments.

For this study, scientists used a well-established model to determine the conspicuousness of three distinct colour morphs of Littorinid snail found commonly along the world’s coastlines.

They compared how the species appeared to three common coastal predators when illuminated by different forms of lighting. This included 20th century narrow spectrum Low Pressure Sodium (LPS) lighting, three types of modern broad spectrum lighting — High Pressure Sodium (HPS); Light Emitting Diodes (LEDs); and Metal Halide (MH) — and the natural light provided by the sun and moon.

Under LPS lighting, all snails were effectively camouflaged. However, when illuminated by LEDs, MH, the sun or the moon, yellow snails were significantly more visible compared to brown and olive ones in the majority of cases.

Dr Thomas Davies, Lecturer in Marine Conservation at the University of Plymouth and the study’s senior author, said: “As technologies develop, there has been a shift from narrow spectrum to lighting that enables us to live and travel in a safe, secure manner. However, estimates suggest that a quarter of the planet between the Arctic Circle and Antarctica is now being affected by night-time light pollution. Some predictions say that LED bulbs will account for 85% of the global street lighting market in around five years, and our study highlights that such advances will have repercussions for humans and animals alike now and in the future.”

Dr Tim Smyth, PML Head of Science for Marine Biogeochemistry and Observations and co-author on the research, added: “The ability to light our environment around the clock has transformed the urban landscapes over the past century and has ushered in what some call the Urbanocene. The shift from the orange glow over cities, typical of my youth in the 1970s and 80s, has now shifted much more towards energy efficient wide spectrum LEDs which even enables us humans to correctly perceive colour. This work shows that this advancement has additional ramifications for the natural world, which is having to adapt at an increasing rate to the artificial changes we are making to the environment. We need to learn to adapt our technologies to avoid the worst consequences of their adoption.”

What can be done to reduce the impact of artificial lighting on our coastlines

With estimates indicating that 23% of the world’s surface, between the planet’s polar regions, are affected by ALAN — and a rate of increase of 2.2% between 2012 and 2016 — the need to address the situation is pressing to say the least.

In the study, the researchers highlight a variety of mitigation methods available to planners and environmental managers when considering its ecological impacts.

These include reducing the amount of light used, shielding lights to reduce their effects on the surrounding environment, employing part-night lighting during times of peak demand, and manipulating the spectra of lighting to minimise ecological impacts.

The researchers highlight that while it may seem intuitive to suggest using narrow spectrum lighting to avoid these impacts, the effects of ALAN extend beyond those seen on camouflage and that all parts of the visual spectrum will likely have some ecological impact.

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Materials provided by University of Plymouth. Original written by Alan Williams. Note: Content may be edited for style and length.

Patients with co-infection of SARS-CoV-2, which causes Covid-19, and influenza viruses were over four times more likely to require ventilation support and 2.4 times more likely to die than if they only had Covid-19, experts found.

Researchers say the findings show the need for greater flu testing of Covid-19 patients in hospital and highlight the importance of full vaccination against both Covid-19 and the flu.

The team from the University of Edinburgh, University of Liverpool, Leiden University and Imperial College London, made the findings in a study of more than 305,000 hospitalised patients with Covid-19.

The research — delivered as part of the International Severe Acute Respiratory and emerging Infection Consortium’s (ISARIC) Coronavirus Clinical Characterisation Consortium — is the largest ever study of people with Covid-19 and other endemic respiratory viruses.

ISARIC’s study was set up in 2013 in readiness for a pandemic such as this.

The team looked at the data of adults who had been hospitalised with Covid-19 in the UK between 6 February 2020 and 8 December 2021.

Test results for respiratory viral co-infections were recorded for 6965 patients with Covid-19. Some 227 of these also had the influenza virus, and they experienced significantly more severe outcomes.

Dr Maaike Swets, PhD student at the University of Edinburgh and Leiden University, said: “In the last two years we have frequently witnessed patients with Covid-19 become severely ill, at times leading to an ICU admission and the employment of an artificial ventilator to help with breathing. That an influenza infection could give rise to a similar situation was already known, but less was understood about the outcomes of a double infection of SARS-CoV-2 and other respiratory viruses.”

Professor Kenneth Baillie, Professor of Experimental Medicine at the University of Edinburgh, said: “We found that the combination of Covid-19 and flu viruses is particularly dangerous. This will be important as many countries decrease the use of social distancing and containment measures. We expect that Covid-19 will circulate with flu, increasing the chance of co-infections. That is why we should change our testing strategy for Covid-19 patients in hospital and test for flu much more widely.”

Professor Calum Semple, Professor of Outbreak Medicine and Child Health at the University of Liverpool, said: “We are seeing a rise in the usual seasonal respiratory viruses as people return to normal mixing. So, we can expect flu to be circulating alongside Covid-19 this winter. We were surprised that the risk of death more than doubled when people were infected by both flu and Covid-19 viruses. It is now very important that people get fully vaccinated and boosted against both viruses, and not leave it until it is too late.”

Dr Geert Groeneveld, doctor at Leiden University Medical Center’s infectious diseases department, said: “Understanding the consequences of double infections of SARS-CoV-2 and other respiratory viruses is crucial as they have implications for patients, hospitals and ICU capacity during seasons that SARS-CoV-2 and influenza circulate together.”

Professor Peter Openshaw, Professor of Experimental Medicine at Imperial College London, said: “Being infected with more than one virus is not very common but it’s important to be aware that co-infections do happen. The vaccines that protect against Covid-19 and flu are different, and people need both. The way that these two infections are treated is also different so it’s important to test for other viruses even when you have a diagnosis in someone who is hospitalised with a respiratory infection. This latest discovery by the ISARIC consortium again adds significantly to improving the way we manage patients.”

The findings have been published in The Lancet. The research was funded by UK Research and Innovation (UKRI) and by the Department of Health and Social Care through the National Institute for Health Research (NIHR) as part of the UK Government’s Covid-19 rapid research response.

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Now, new research by University of Alberta immunologist Shokrollah Elahi reveals a possible answer to the mystery of why infected people can’t get rid of HIV altogether.

Elahi and his team found that in HIV patients, killer T cells — a type of white blood cells responsible for identifying and destroying cells infected with viruses — have very little to none of a protein called CD73.

Because CD73 is responsible for migration and cell movement into the tissue, the lack of the protein compromises the ability of killer T cells to find and eliminate HIV-infected cells, explained Elahi.

“This mechanism explains one potential reason for why HIV stays in human tissues forever,” he said, adding that the research also shows the complexity of HIV infection.

“This provides us the opportunity to come up with potential new treatments that would help killer T cells migrate better to gain access to the infected cells in different tissues.”

After identifying the role of CD73 — a three-year project — Elahi turned his focus to understanding potential causes for the drastic reduction. He found it is partly due to the chronic inflammation that is common among people living with HIV.

“Following extensive studies, we discovered that chronic inflammation results in increased levels of a type of RNA found in cells and in blood, called microRNAs,” he explained. “These are very small types of RNA that can bind to messenger RNAs to block them from making CD73 protein. We found this was causing the CD73 gene to be suppressed.”

The team’s discovery also helps explain why people with HIV have a lower risk of developing multiple sclerosis, Elahi noted.

“Our findings suggest that reduced or eliminated CD73 can be beneficial in HIV-infected individuals to protect them against MS. Therefore, targeting CD73 could be a novel potential therapeutic marker for MS patients.”

Elahi said the next steps in his research include identifying ways the CD73 gene can be manipulated to turn on in patients living with HIV and off in those with MS.

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Materials provided by University of Alberta. Original written by Tarwinder Rai. Note: Content may be edited for style and length.

“With the help of advanced laboratory techniques, we were able to identify a panel of nanobodies that very effectively neutralized several variants of SARS-CoV-2,” says Gerald McInerney, professor at the Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, and joint senior author of both studies.

Despite the roll-out of vaccines and antivirals, the need for effective therapeutics against severe COVID-19 infection remains high. Nanobodies — which are fragments of antibodies that occur naturally in camelids and can be adapted for humans — are promising therapeutic candidates as they offer several advantages over conventional antibodies. For example, they have favourable biochemical properties and are easy to produce cost-effectively at scale.

In the now published studies, the labs of Gerald McInerney and Ben Murrell, also at MTC, identify several potent nanobodies derived from an alpaca immunised with SARS-CoV-2 antigens.

The first report in Nature Communications describes a single nanobody, Fu2 (named after the alpaca Funny), that significantly reduced the viral load of SARS-CoV-2 in cell cultures and mice. Using electron cryo-microscopy, the researchers found that Fu2 naturally binds to two separate sites on the viral spike, thus inhibiting the virus’ ability to enter the host cell. This part of the study was conducted in collaboration with Hrishikesh Das and Martin Hällberg at the Department of Cell and Molecular Biology at Karolinska Institutet.

The researchers next delved deeper into the alpaca’s nanobody repertoire by combining a range of advanced laboratory techniques and computational methods, resulting in a library of nanobodies described in detail.

The results, presented in Science Advances, revealed additional nanobodies that in cell cultures and mice effectively cross-neutralized both the founder and beta variant of SARS-CoV-2 and even neutralized the more distantly related SARS-CoV-1.

“These nanobodies represent promising therapeutic candidates against several SARS-CoV-2 variants,” says first author Leo Hanke, a postdoctoral researcher who established the nanobody technology in the McInerney group.

The researchers are currently applying the same techniques to identify which nanobodies from this set are best able to neutralize Omicron, the now dominating SARS-CoV-2 variant.

“Once established, these libraries can be expanded and mined for nanobodies that neutralize new emerging variants,” says Assistant Professor Ben Murrell, also joint senior author of both studies.

Funding was provided by David and Astrid Hagelén Foundation, the Clas Groschinskys Minnesfond and a Jonas Söderquist’s scholarship, European Union’s Horizon 2020 research and innovation program, Swedish Research Council, and Knut and Alice Wallenberg Foundation.

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Scientists working on the neuroscience of attention have recently become concerned that because both attention and eye movements, like microsaccades, involve the same groups of neurons in the brain, that microsaccades might be required for shifting attention.

“If microsaccades were driving attention, that would bring into question a lot of previous research in the field.” said Richard Krauzlis, Ph.D., chief of the NEI Section on Eye Movements and Visual Selection, and senior author of a study report on the research. “This work shows that while microsaccades and attention do share some mechanisms, covert attention is not driven by eye movements.”

Krauzlis’ previous research has shown that covert attention causes a modulation of certain neuronal signals in an evolutionarily ancient area of the brain called the superior colliculus, which is involved in the detection of events. When attention is being paid to a particular area — for example, the right-hand side of one’s peripheral vision — signals in the superior colliculus relating to events that occur in that area will receive an extra boost, while signals relating to events occurring somewhere else, like on the left-hand side, will be depressed.

When something shows up in our peripheral vision, we quickly shift our eyes — make a large saccade toward the event to take a better look. This movement brings the event into our high-resolution central vision. These eye movements are accompanied by a general decrease in visual signals, as the brain ignores the quickly shifting visual information received by the eye. In laboratory studies of covert attention, primates or people are directed to avoid those types of large saccades, keeping the attended event in the peripheral vision. However, involuntary microsaccades, which are accompanied by similar decreases in visual signals, often occur anyway.

In this study, led by first author Gongchen Yu, Ph.D., the researchers asked whether attention-based signal changes in the superior colliculus are driven by microsaccades, or if the two processes can be separated.

The researchers trained monkeys to hold their eyes straight ahead, while attending to their peripheral vision. The researchers would cue either the left or right side by flashing a ring on the “cued” side. After the cue, the monkeys would release a joystick if they detected a color change on the cued side, while ignoring any color changes on the uncued side. The researchers could measure changes in neuronal activity on both sides of the superior colliculus, detecting a boost to the cued side, and lower signals on the uncued side.

At the same time, the researchers used high-resolution eye-tracking cameras to measure microsaccades during the trials. Sometimes, there would be no microsaccades. In other trials, the monkeys would make a microsaccade toward the cued side, or away from the cued side. By lining up the signals based on the time any microsaccade began, the researchers found that the neuronal signals for attention in the superior colliculus were present before the microsaccade, and then would re-establish after the microsaccade.

In essence, although the eye movement would also trigger changes to neuronal signals in the superior colliculus, attention-related signals occurred independently of the eye movement signals.

“While the neuronal circuits activated by these two systems do overlap, the link between microsaccades and attention is not a causal one,” Krauzlis said.

“The majority of vision neuroscientists have been using this type of experimental system to study visual attention for decades. It’s a big relief to reconfirm that microsaccades are not the driver of the neuronal changes seen with visual attention,” said Yu. “This result means we don’t need to reevaluate decades of work!”

This study was funded by the NEI Intramural Program.

“Based on this idea, we proposed a concept that this will be a pH-responsive material. If we change the pH value, we can control the molecular diffusion,” said Dr. Qingsheng Wang, associate professor in the Artie McFerrin Department of Chemical Engineering and holder of the George Armistead ’23 Faculty Fellowship at Texas A&M.

The team’s research was published in the American Chemical Society’s journal, ACS Applied Materials & Interfaces.

Emulsion is a mixture of two or more incompatible and unmixable liquids, much like oil and water, that can be stabilized by the interference of solid particles. These solid particles tightly assemble at the fluid-fluid interface, like swim lanes in a lap pool, to prevent coalescence. This process is known as Pickering emulsion.

The success of this system is ultimately made possible by the use of graphene quantum dots (GQDs) containing zwitterionic properties. Using several sheets of GQDs stacked together, the research team is able to not only stabilize emulsion, but also control the molecular diffusion on the interface by adjusting its pH values, much like flipping a light switch. These sheets together measure less than 5 nanometers in thickness. To put this into perspective, the average human hair is anywhere from 80,000 to 100,000 nanometers wide.

The functionalized GQDs are composed of nanocarbon materials containing zwitterionic structure, which is formed from nanoparticles that contain an equal amount of both positive and negative charges while still remaining electronically neutral. After the nanoparticles are added to the interface, they separate the two fluids by making one side hydrophobic and the other side hydrophilic.

This electronic makeup also makes it possible to control the overall pH of the interface. By adjusting the pH values, these GQDs can be finely tuned to both block and unblock an oil-water interface. Changing the nanoplatelets on the interface to the same charge means that they will be disassembled, thus creating a more stable emulsion system.

“This is going to help us design a good system in high-performance fire suppression. In addition, because we can control the release, this could be promising for drug delivery and enhanced oil recovery,” Wang said. “Usually, this is very difficult to do. And sometimes, if we can control the release, but the system itself is not stable, it may only be possible to do one or two cycles of this before the system collapses.”

The research team consists of chemical engineering doctoral student Rong Ma and former chemical engineering doctoral students Dr. Minxiang Zeng, now a research scientist at the University of Notre Dame, and Dr. Dali Huang, now a process engineer at Formosa Plastics Corporation.

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Materials provided by Texas A&M University. Original written by Alleynah Veatch Cofas. Note: Content may be edited for style and length.

The vertical wind tunnel at Johannes Gutenberg University Mainz (JGU), which is the only one of its kind in the world, is providing essential information in this connection through new experiments that are being conducted using artificial hailstones made by a 3D printer. “One thing we have learned so far is that it is the form of hailstones that determines their velocity prior to impact,” explained Dr. Miklós Szakáll of the Institute of Atmospheric Physics (IPA) at JGU. Szakáll’s team has been able to demonstrate that lobed hailstones develop less kinetic energy and thus less destructive potential than hail with a smooth surface.

Hail and graupel, which is the term used to describe precipitated small, soft ice pellets, are formed when water droplets freeze within storm clouds. This freezing process is promoted by turbulences and complex physical processes in these clouds that can extend to very high altitudes. These ice particles melt if they pass through warmer air layers on the way down. The result is large, cold raindrops and these are often the culprits behind extreme rainfall precipitation. Assuming that the ice particles do not have time to melt completely before reaching the ground, they arrive in the form of hail or graupel.

Experiments with natural and artificial hailstones

The conditions in the interior of clouds determine the characteristic form, size, and mass of these frozen droplets. “In our experiments with natural hailstones, we have seen that they melt to form raindrops that can be several millimeters in diameter. Large hailstones can also burst during the melting process, forming numerous small water droplets,” Szakáll added. From the recorded measurements, his team was able to extrapolate parameters that they could use as the main elements for the numerical simulation of clouds and precipitation in computer models.

The research team in Mainz produced hailstones and graupel particles from frozen water in the lab. Employing realistic temperature and humidity conditions, the researchers looked closely at how these fell or melted in the vertical wind tunnel. In addition, they used a 3D printer to create artificial hail and graupel pellets modeled on their natural counterparts — even the material density corresponded with that of ice. They used these to measure the free fall properties of the descending objects, factors that are particularly relevant to the microphysical processes in extreme precipitation events.

The hail and graupel pellets were suspended freely in an artificially produced vertical air stream in the six-meter-high wind tunnel. Their behavior was recorded using high speed and infrared cameras and a specially developed holographic imaging system.

“If we apply the insights into microphysical aspects of precipitation we have obtained through these experiments to models used for the analysis of storm clouds, we can better anticipate what they will do,” explained Professor Stephan Borrmann of the IPA and Director at the Max Planck Institute for Chemistry. “This becomes particularly significant in view of the probable increase in extreme weather events, such as drought and torrential rainfall, that will occur even in our part of the world due to climate change,” emphasized Borrmann.

The experiments in Mainz were undertaken under the aegis of the HydroCOMET project sponsored by the German Research Foundation (DFG). The results have been published in five peer-reviewed journals and as a book contribution.

The experts reviewing the HydroCOMET findings provided very positive assessments of the lab experiments performed in Mainz and the associated publications. They particularly stressed the important role played by the available infrastructure, i.e., the vertical wind tunnel.

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