Brain

Rain is a common phenomenon on Earth. There is a similar phenomenon on the Sun, called coronal rain. It is related to the coronal heating and magnetic field, and plays a fundamental role in the mass cycle between the hot, tenuous corona and the cool, dense chromosphere.

Coronal rain usually takes place in post-flare loops and the non-flaring active region coronal loops. It is generally classified into two categories: flare-driven and quiescent coronal rain, depending on its relation to the flare. Both kinds of coronal rain form along structures that are magnetically closed.

Recently, a research team led by Dr. LI Leping from the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC) found a new type of coronal rain forming along open magnetic structures, away from the magnetically closed region.

A series of studies has been issued since 2018, among which the latest paper was published in The Astrophysical Journal on April 1.

The researchers proposed a new formation mechanism for coronal rain along open magnetic structures facilitated by interchange magnetic reconnection between open and closed magnetic structures.

In this formation mechanism, the higher-lying open structures reconnect with the lower-lying closed loops, forming a magnetic dip in the former. The plasma, surrounding the dip, converges into the dip, resulting in the enhancement of plasma density in the dip. The density enhancement triggers thermal instability. Cooling and condensation of hot coronal plasma in the dip thus occurs. The cool condensation falls toward the solar surface as coronal rain.

No flare was detected during the reconnection and condensation process. The new type of coronal rain thus belongs to the category of quiescent coronal rain.

"The quiescent coronal rain forming along the open structures is quite different from the flare-driven coronal rain in post-flare loops and the quiescent coronal rain in non-flaring active region loops that occur in the closed loops," said Dr. LI Leping, the first author of the series of studies.

All the reconnection and condensation events investigated before took place above the limb.

"Whether the condensation facilitated by reconnection can still be observed on the disk, and how it performs, are open questions," said Prof. Hardi Peter from the Max Planck Institute for Solar System Research (MPS), a co-author of the series of studies.

The researchers found that the reconnection condensation events from September 2010 - September 2011, observed above the eastern (western) limb of the Solar Terrestrial Relations Observatory (STEREO A (B)), occurred on the disk of the Solar Dynamics Observatory (SDO).

"The event presented is important for understanding the global picture of condensation formation in the solar atmosphere and the combined observations bring a very interesting means to analyze this type of coronal condensation events," the reviewer of the paper commented.

Above the limb, the bright condensations and the subsequent coronal rain, facilitated by reconnection between open and closed structures, were clearly detected. However, on the disk, the reconnection structures were difficult to observe. Moreover, dark condensations appeared and moved to the surface as on-disk coronal rain.

"If only the on-disk observations are available, the relation between the condensations and reconnection, shown clearly by the off-limb observations, could not be identified," said Dr. LI. "We propose that some on-disk condensation events seen in the transition region and chromospheric lines could be facilitated by interchange reconnection."

Chestnut Hill, Mass. (4/22/2021) - Confirming anecdotal evidence that the spread of the coronavirus has strained Americans' mental health, Boston College researchers found reports of anxiety increased to 50 percent and depression to 44 percent by November, 2020 - rates six times higher than 2019 - according to a new report in the journal Translational Behavioral Medicine.

Among U.S. adults aged 18-29, the impact on mental health was even more severe. Rates of anxiety and depression increased to 65 percent and 61 percent, respectively, of the respondents in that age group, according to the report.

Use of prescription medication, counseling services, and unmet need for mental health services also rose significantly, according to the co-authors of the new study, Boston College developmental psychologist Rebekah Levine Coley and economist Christopher F. Baum, who reviewed survey data from nearly 1.5 million U.S. adults.

Rates of mental health disorders were highest among young, less-educated, single parent, female, Black and Hispanic respondents, Coley and Baum report. Disparities between young versus older and less educated versus more educated adults rose over time. Young, female, and moderately educated respondents also reported higher unmet needs for services.

"Disparities in estimates of mental health disorders and mental health treatment indicate a striking disequilibrium between the potential need for and the use of mental health services during the COVID-19 pandemic," said Coley, a professor in the Lynch School of Education and Human Development. "Rising mental health challenges are being borne largely by young, less advantaged people of color, and women, with the potential for expanded interruptions to optimal functioning and societal recovery from COVID-19."

Despite extensive anecdotal evidence of rising mental health challenges posed by the pandemic, little prior evidence had systematically assessed rates of mental health disorders or use of mental health symptoms through the course of the COVID-19 pandemic, said Coley.

"We discerned a need to track rates of depression and anxiety, as well as rates of use of mental health services and reports of unmet need for such services between April and November, 2020," she said. "We also sought to assess whether the rates of mental health disorders and service use varied across key demographic groups in the U.S."

The researchers analyzed data gathered between April and November 2020 as part of the U.S. Census' Household Pulse Survey, a series of cross-sectional surveys conducted weekly. Survey respondents self-reported their symptoms of anxiety and depression, use of medication, use of counseling services, and unmet need for services. Coley and Baum analyzed these surveys to track trends in mental health disorder symptoms and access to and use of mental health services.

While the researchers expected to see increases in the rates of depression and anxiety, they were surprised by the magnitude of the increases, Coley said.

"The fact that prevalence rates were six times higher than national norms from 2019 was striking, as was the fact that these increases were born primarily by younger adults, aged 18-29 years, whose rates of anxiety and depression were nearly twice as high as those of older adults, aged 70 and above," Coley said.

The analysis reveals a need for continued study of the pandemic's impact on mental health.

The findings suggest the need for increased access to mental health services and other supports to help adults face the economic, social, and psychological stressors of the COVID-19 pandemic, Coley said. There is also a need to assess whether rising mental health challenges continue to grow as the pandemic rages on, and to delineate the longer-term effects of the social, economic, and psychological disruptions caused by COVID-19. For young adults particularly, the pandemic may have interrupted higher education plans and the initiation of careers and social and financial independence, with unknown long-term repercussions.

"The myriad stressors imposed by the COVID-19 pandemic have impaired mental health and well-being," said Baum, who also holds an appointment at BC's School of Social Work. "Although evidence from early in the pandemic revealed elevated rates of mental health conditions, research had not documented whether psychological disorders have continued to rise as the pandemic has persisted, or for whom they have risen most dramatically."

For reasons not yet clear, pregnant women infected with the virus that causes COVID-19 are more likely to experience preterm births, pre-eclampsia, and other neonatal problems than non-infected women.

A team of Yale scientists decided to investigate whether the virus could be affecting placental tissue of infected expectant mothers. Their analysis found that while evidence of the virus in the placenta is rare, the placenta in infected mothers tended to exhibit a much higher level of immune system activity than those of non-infected pregnant women, they report April 22 in the journal Med.

"The good news is the placenta is mounting a robust defense against an infection that is far distant, in lungs or nasal tissue," said Shelli Farhadian, assistant professor of internal medicine (infectious diseases) and neurology at Yale and co-corresponding author. "On the other hand, the high level of immune system activity might be leading to other deleterious effects on the pregnancy."

The team headed by Farhadian and Akiko Iwasaki, the Waldemar Von Zedtwitz Professor of Immunobiology at Yale, analyzed blood and placental tissue in 39 infected and as well as COVID-free expectant mothers at different stages of pregnancy. While they found evidence of the virus in only two samples of placental tissue, they did find ACE2 receptors -- which the SARS-CoV-2 virus uses to enter cells -- in the placentas of most women during the first trimester of pregnancy. Those receptors had largely disappeared in healthy women at later stages of pregnancy.

"It is very important to closely monitor expectant mothers who become infected early in pregnancy," Farhadian said.

Immune system activity in the placenta during infections like COVID-19 has not been extensively studied and it is not known whether other types of infections would behave similarly to SARS-CoV-2, she said.

A study that appeared today on Current Biology sheds new light on the continental migrations which shaped the genetic background of all present Europeans. The research generates new ancient DNA evidence and direct dating from a fragmentary fossil mandible belonging to an individual who lived ~17,000 years ago in northeastern Italy (Riparo Tagliente, Verona). The results backdate by about 3,000 years the diffusion in Southern Europe of a genetic component linked to Eastern Europe/Western Asia previously believed to have spread westwards during later major warming shifts.

"By looking into the past of this particular individual, who was one of the first settlers of the southern Alps after the Last Glacial peak, we found evidence that the previously documented genetic replacement which changed the makeup of Southern European Hunter Gatherers started at least 17,000 years ago," said lead author Eugenio Bortolini (University of Bologna), "much earlier than we previously thought, and in a very different scenario".

The ancient genome obtained at Riparo Tagliente is in fact of particular importance, "since it supports the persistence of exchange networks and the movement of people across southern Europe immediately after the Last Glacial Maximum, well before the onset of much warmer climatic shifts," said Luca Pagani (University of Padova and Institute of Genomics of the University of Tartu), co-first author of the work.

This individual, whose half-mandible had been found at Riparo Tagliente in 1963, shares genetic affinities with an Iberian individual who lived up to 19,000 years ago, and maternal and paternal genetic affinities with southern Italian and European individuals who lived around 14,000 years ago, suggesting that population movements may have spread these genetic variants in Southern Europe even before the occupation of Riparo Tagliente, and may have been intermittent but persisting during colder phases. "Direct dating of human fossils is once again critical to disentangle and interpret complex archaeological contexts", adds Sahra Talamo, coauthor of the study.

The analysis of the mandible also allowed the authors to unveil some details concerning this particular settler of Riparo Tagliente: "The fragment belongs to a young male affected by cementoma, a quite rare anomaly in the development of dental tissue" adds Gregorio Oxilia, co-first author of the study, "and might shed light on the distribution of such conditions in pre-Neolithic societies".

The research was coordinated by the University of Bologna (Italy) in close collaboration with a vast international network including the University of Padova (Italy), the Institute of Genomics of the University of Tartu (Estonia), the University of Tu?bingen (Germany), the University of Ferrara (Italy), the Institute of Genetics and Biophysics of the National Research Council of Italy, KU Leuven (Belgium), Institució Milà i Fontanals of the Spanish National Research Council, Sequentia Biotech (Spain), University of Venice Ca' Foscari (Italy), The "Abdus Salam" International Centre for Theoretical Physics (Trieste, Italy), Monash University (Melbourne , Australia), University of Florence (Italy), and several professional dentist surgeons. Excavations at Riparo Tagliente which made this study possible are led and supervised by Federica Fontana and coordinated by the University of Ferrara.

"This finding opens important questions concerning the role and impact of population movements on the major cultural transitions documented by archaeologists in Southern Europe" concludes Stefano Benazzi, senior author of the study, "some of which temporally coincide with the date emerged for the individual found at Riparo Tagliente. Future research will dig more into these new hypotheses concerning the ancestry of modern Europeans".

Certain signalling proteins, which are responsible for the development of innate immune function in almost all animals are also required for the formation of the dorsal-ventral (back-belly) axis in insect embryos. A new study by researchers from the University of Cologne's Institute of Zoology suggests that the relevance of these signalling proteins for insect axis formation has increased independently several times during evolution. For example, the research team found similar evolutionary patterns in the Mediterranean field cricket as in the fruit fly Drosophila, although the two insects are only very distantly related and previous observations suggested different evolutionary patterns. The new findings show that the evolution of axis formation in insects was actually much more complex than previously thought. The study has been published in eLife.

Signalling proteins play an important role in the early development of embryos. They are secreted by animal cells to influence the formation of other cells. The primary function of the so-called Toll signalling pathway is in the defence against pathogens (innate immune response). In insects, it is also involved in the division of the insect body along the dorsal-ventral body axis. Since the immune function has been found in almost all animals, but the axis formation function has only been found in insects, scientists wondered about the evolutionary history of this new role. Moreover, depending on the insect species, the significance of Toll for developmental processes differs. While axis formation in the fruit fly and flour beetle depend substantially on Toll, representatives of distantly related species, such as the wasp Nasonia and the milkweed bug Oncopeltus, rely more heavily on other signalling pathways. 'Surprisingly, we found that the Toll signalling pathway plays a significant role in an insect that is separated by almost 400 million years from the species we studied so far,' said Professor Dr Siegfried Roth from the Institute of Zoology. 'The new study suggests that there might be several instances in which Toll independently acquired important functions in insect axis formation. For future studies, this means that our system allows us to explore mechanisms of parallel evolution.'

PHILADELPHIA--Piperlongumine, a chemical compound found in the Indian Long Pepper plant (Piper longum), is known to kill cancerous cells in many tumor types, including brain tumors. Now an international team including researchers from the Perelman School of Medicine at the University of Pennsylvania has illuminated one way in which the piperlongumine works in animal models -- and has confirmed its strong activity against glioblastoma, one of the least treatable types of brain cancer.

The researchers, whose findings were published this month in ACS Central Science, showed in detail how piperlongumine binds to -- and hinders the activity of -- a protein called TRPV2, which is overexpressed in glioblastoma in a way that appears to drive cancer progression. The scientists found that piperlongumine treatment radically shrank glioblastoma tumors and extended life in two mouse models of this cancer, and also selectively destroyed glioblastoma cells taken from human patients.

"This study gives us a much clearer picture of how piperlongumine works against glioblastoma, and in principle enables us to develop treatments that can be even more potent," said study co-senior author Vera Moiseenkova-Bell, PhD, an associate professor of Pharmacology and faculty director of the Electron Microscopy Resource Laboratory and Beckman Center for Cryo Electron Microscopy at Penn Medicine.

The study was a collaboration led by the laboratory of co-senior author Gonçalo J. L. Bernardes, DPhil, of the Institute of Molecular Medicine, University of Lisbon and the University of Cambridge.

"We are thrilled with the prospect of bringing our findings from bench to bedside to make a real impact on the health of people suffering from this horrendous disease," Bernardes said.

The project began as a broad investigation of how piperlongumine exerts an anticancer effect. Bernardes and colleagues used an advanced machine-learning strategy to determine that the compound likely interacts with a family of proteins called TRP ion channels.

Ion channels are tiny molecular tubes that typically sit within cell membranes and allow incoming or outgoing flows of charged molecules ("ions"), such as calcium, potassium, and sodium. The channels usually are sensitive to some stimulus -- a class of chemicals, mechanical force, or temperature, for example -- which opens or closes the channels, effectively regulating the ion flow. Initial experiments by Bernardes and colleagues revealed that piperlongumine acts as an inhibitor -- a channel closer -- of a type of TRP ion channel called TRPV2, which exists in many cell types but has functions that are not well understood.

The researchers then turned to Moiseenkova-Bell, whose lab specializes in cryo-electron microscopy (cryo-EM) and has deep experience using that technology to determine the high-resolution structural details of TRP ion channels. She and her team were able to show precisely where piperlongumine binds to TRPV2 to inhibit its activity.

Bernardes and colleagues, in another set of experiments, examined a broad array of cancers and determined that glioblastoma multiforme, the most common form of brain cancer and one that is notoriously difficult to treat, overexpresses TRPV2 and is highly sensitive to its loss. Moreover, they linked higher levels of TRPV2 to greater aggressiveness in the tumor and poorer prognosis for the patient.

Brain cancers like glioblastoma are hard to treat with ordinary drugs in part because drug molecules usually don't cross easily from the bloodstream into the brain. The team therefore devised a hydrogel-type scaffold that could be filled with piperlongumine and implanted. They showed in two different glioblastoma mouse models that their piperlongumine-filled scaffold, which releases piperlongumine in the area of a tumor for about eight days at a time, destroyed the glioblastomas almost completely and greatly extended mouse survival beyond that of untreated mice. The researchers obtained similar results against glioblastoma cells from human patients.

Bernardes and colleagues are now working to develop their approach in further preclinical studies, with the hope of one day testing it in clinical trials with glioblastoma patients. In addition, Moiseenkova-Bell's structural findings will enable the researchers to experiment with piperlongumine and modified versions of it to develop an even stronger and more selective inhibitor of TRPV2.

Moiseenkova-Bell and her lab are also investigating molecular mechanisms of TRPV2 gating and more generally what TRPV2 does in the human body.

BUFFALO, N.Y. -- In nature, many molecules possess a property called chirality, which means that they cannot be superimposed on their mirror images (like a left and right hand).

Chirality can influence function, impacting a pharmaceutical or enzyme's effectiveness, for example, or a compound's perceived aroma.

Now, a new study is advancing scientists' understanding of another property tied to chirality: How light interacts with chiral materials under a magnetic field.

Prior research has shown that in such a system, the left- and right-handed forms of a material absorb light differently, in ways that mirror one another when light flowing parallel to an external magnetic field changes direction, adopting an anti-parallel flow. This phenomenon is called magneto-chiral dichroism (MChD).

Missing, however, from past experiments was a confirmation that experimental observations match up with predictions made by MChD theory -- a necessary step in verifying the theory and understanding the effects scientists have observed.

The new paper, which will be published on April 21 in Science Advances, changes this. The study was led by Geert L. J. A. Rikken, PhD, director of the Laboratoire National des Champs Magnétiques Intenses in France, and Jochen Autschbach, PhD, Larkin Professor of Chemistry at the University at Buffalo in the U.S. The first authors were Matteo Atzori, PhD, a researcher at the Laboratoire National des Champs Magnétiques Intenses, and UB chemistry PhD student Herbert Ludowieg.

"The first theoretical predictions of MChD for light appeared in 1980s. Since then, an increasing number of observations of the effect have been reported, but no quantitative analysis was possible to confirm whether the underlying theory of MChD is correct," Rikken says. "The new study puts forward detailed measurements on two well-defined model systems, and advanced quantum-chemical calculations on one of them."

"Dr. Rikken's team made the first experimental observation of MChD in 1997 and has since reported other experimental studies of the effect in different systems," Autschbach says. "However, only now has a direct comparison between an experiment and ab-initio quantum theoretical calculations become possible, for a verification of the MChD theory."

The research focused on crystals consisting of the mirrored forms of two compounds: tris(1,2-diaminoethane)nickel(II)nitrate, and tris(1,2-diaminoethane)cobalt(II)nitrate. As Autschbach explains, "the molecular shape of the tris(1,2-diaminoethane)metal(II) ion in the crystal has a propeller-like shape. Propellers come in pairs of mirror images, too, that cannot be superimposed."

Rikken's lab made detailed experimental measurements for both systems studied, while Autschbach's group leveraged UB's supercomputing facility, the Center for Computational Research, to carry out challenging quantum-chemical calculations relating to light absorption by the nickel(II) compound.

The results, as explained in the Science Advances paper: "We report the experimental low-temperature MChD spectra of two archetypal chiral paramagnetic crystals taken as model systems, tris(1,2-diaminoethane)nickel(II) and cobalt(II) nitrate, for light propagating parallel or perpendicular to the c-axis of the crystals, and the calculation of the MChD spectra for the Ni(II) derivative by state-of-the-art quantum chemical calculations.

"By incorporating vibronic coupling, we find good agreement between experiment and theory, which opens the way for MChD to develop into a powerful chiral spectroscopic tool and provide fundamental insights for the chemical design of new magnetochiral materials for technological applications."

While the study is in the realm of basic science, Rikken notes the following with regard to the future potential of MChD: "We find experimentally that (for the materials we studied), at low temperatures, the difference in light transmission parallel and anti-parallel to a modest magnetic field of 1 Tesla, hardly more than what a refrigerator magnet produces, can be as high as 10%. Our calculations permit us to understand this in detail. The size of the effect and its detailed understanding now open the door to future applications of MChD, which could range from optical diodes to new optical data storage methods."

Video: https://bit.ly/pelicanflightvideo

It's a common sight: pelicans gliding along the waves, right by the shore. These birds make this kind of surfing look effortless, but actually the physics involved that give them a big boost are not simple.

Researchers at the University of California San Diego have recently developed a theoretical model that describes how the ocean, the wind and the birds in flight interact in a recent paper in Movement Ecology.

UC San Diego mechanical engineering Ph.D. student Ian Stokes and adviser Professor Drew Lucas, of UC San Diego's Department of Mechanical and Aerospace Engineering and Scripps Institution of Oceanography, found that pelicans can completely offset the energy they expend in flight by exploiting wind updrafts generated by waves through what is known as wave-slope soaring. In short, by practicing this behavior, sea-birds take advantage of winds generated by breaking waves to stay aloft.

The model could be used to develop better algorithms to control drones that need to fly over water for long periods of time, the researchers said. Potential uses do not stop there.

"There's a community of biologists and ornithologists that studies the metabolic cost of flight in birds that can use this and see how their research connects to our estimates from theory. Likewise, our model generates a basic prediction for the winds generated by passing swell, which is important to physicists that study how the ocean and atmosphere interact in order to improve weather forecasting," Stokes said.

"This is an interesting project because it shows how the waves are actually moving the air around, making wind. If you're a savvy bird, you can optimize how you move to track waves and to take advantage of these updrafts. Since seabirds travel long distances to find food, the benefits may be significant," Lucas said.

Stokes and Lucas are, of course, not the first scientists to study the physics of the atmosphere that pelicans and other birds are hardwired to intuit so they can conserve energy for other activities. For centuries, humans have been inspired by the sight of birds harnessing the power and patterns of the winds for soaring flight.

That's how it started with Stokes, who is now in the second year of his PhD at UC San Diego. As a UC Santa Barbara undergraduate, Stokes, a surfer and windsurfer in his off hours, needed a project for his senior physics class and thought of the birds that would accompany him on the waves. When he looked closer, he appreciated the connection between their flight dynamics and the study of environmental fluid dynamics, a speciality of scientists at UC San Diego. The project ultimately turned into a master's thesis with Lucas, drawing inspiration from oceanographers at Scripps who seek to understand the interactions between the ocean and atmosphere.

Wave-slope soaring is just one of the many behaviors in sea-birds that take advantage of the energy in their environment. By tapping into these predictable patterns, the birds are able to forage, travel, and find mates more effectively.

"As we appreciate their mastery of the fluid, ever-changing ocean environment, we gain insight into the fundamental physics that shape our world," said Lucas.

DURHAM, N.C. -- When marine biologist Eleanor Caves of the University of Exeter thinks back to her first scuba dives, one of the first things she recalls noticing is that colors seem off underwater. The vivid reds, oranges, purples and yellows she was used to seeing in the sunlit waters near the surface look increasingly dim and drab with depth, and before long the whole ocean loses most of its rainbow leaving nothing but shades of blue.

"The thing that always got me about diving was what happens to people's faces and lips," said her former Ph.D. adviser Sönke Johnsen, a biology professor at Duke University. "Everybody has a ghastly sallow complexion."

Which got the researchers to thinking: In the last half-century, some fish have been shifting into deeper waters, and climate change is likely to blame. One study found that fish species off the northeastern coast of the United States descended more than one meter per year between 1968 and 2007, in response to a warming of only about one degree Celsius.

Could such shifts make the color cues fish rely on for survival harder to see?

Previous research suggests it might. Scientists already have evidence that fish have a harder time discerning differences in each other's hues and brightness in waters made murkier by other causes, such as erosion or nutrient runoff.

As an example, the authors cite studies of three-spined sticklebacks that breed in the shallow coastal waters of the Baltic Sea, where females choose among males -- who care for the eggs -- based on the redness of their throats and bellies. But algal blooms can create cloudy conditions that make it harder to see, which tricks females into mating with less fit males whose hatchlings don't make it.

The turbidity makes it harder for a male to prove he's a worthy mate by interfering with females' ability to distinguish subtle gradations of red or orange, Johnsen said. "For any poor fish that has beautiful red coloration on his body, now it's like, 'well, you're just going to have to take my word for it.'"

Other studies have shown that, for cichlid fish in Africa's Lake Victoria, where species rely on their distinctive colors to recognize their own kind, pollution can reduce water clarity to a point where they lose the ability to tell each other apart and start mating every which way.

The researchers say the same communication breakdown plaguing fish in turbid waters is likely happening to species that are being pushed to greater depths. And interactions with would-be mates aren't the only situations that could be prone to confusion. Difficulty distinguishing colors could also make it harder for fish to locate prey, recognize rivals, or warn potential predators that they are dangerous to eat.

In a study published April 21 in the journal Proceedings of the Royal Society B, Caves and Johnsen used mathematical models to determine what the colors of the underwater world might look like as fish in the uppermost layer of the ocean shift to new depths.

They were able to show that, while the surface waters may be bursting with color, descending by just 30 meters shrinks the palette considerably.

"It's like going back to the days of black and white TV," Johnsen said.

When sunlight hits an object, some wavelengths are absorbed and others bounce off. It's the wavelengths that are reflected back that make a red fish look red, or a blue fish blue. But a fish sporting certain colors at the surface will start to look different as it swims deeper because the water filters out or absorbs some wavelengths sooner than others.

The researchers were surprised to find that, especially for shallow-water species such as those that live in and around coral reefs, it doesn't take much of a downward shift to have a dramatic effect on how colors appear.

"You really don't have to go very far from the surface to notice a big impact," said Caves, who will be starting as an assistant professor at the University of California, Santa Barbara, this fall.

Precisely which colors lose their luster first, and how quickly that happens as you go down, depends on what depths a species typically inhabits and how much deeper they are forced to go, as well as the type of environment they live in -- whether it's, say, the shallow bays or rocky shores of the Atlantic, or a tropical coral reef.

In clear ocean water, red is the first color to dull and disappear. "That's important because so many species use red signals to attract mates or deter enemies," Johnsen said.

The team predicts that some species will be more vulnerable than others. Take, for instance, fish that can't take the edge off the heat by relocating toward the poles of the planet. Particularly in semi-enclosed waters such as the Mediterranean and Black seas or the Gulf of Mexico, or in coral reefs, which are stuck to the sea bed -- these species will have no option but to dive deeper to keep their cool, Caves said.

As a next step, they hope to test their ideas in the coral reefs around the island of Guam, where butterflyfishes and fire gobies use their vivid color patterns to recognize members of their own species and woo mates.

"The problem is only accelerating," Caves said. By the end of this century, it's possible that sea surface temperatures will have heated up another 4.8 degrees Celsius, or an increase of 8.6 degrees Fahrenheit, compared to the 1896-2005 average.

And while warming is happening faster at the poles, "tropical waters are feeling the effects too," Caves said.

Much of common pharmaceutical development today is the product of laborious cycles of tweaking and optimization. In each drug, a carefully concocted formula of natural and synthetic enzymes and ingredients works together to catalyze a desired reaction. But in early development, much of the process is spent determining what quantities of each enzyme to use to ensure a reaction occurs at a specific speed.

New collaborative research from Northwestern University could expedite, or even eliminate, the need for scientists to manually adjust bioproduction reaction conditions at all. Using ideas conceived by graduate students across three labs, Northwestern researchers developed technology that allows microbes to produce drugs with feedback control systems, dialing down or amping up protein concentration as needed.

Implications for this research are vast. With the knowledge that microbial feedback control systems could be used more generally to produce other drugs and products, the ability for microbes to be self-regulating means other important classes of therapeutics may be newly accessible to developers.
Currently, because production pathways can be toxic to cells at certain levels, scientists have faced hurdles to engineering such microbes that leverage these pathways. But with the help of tools from the lab of Julius B. Lucks, an associate professor at the McCormick School of Engineering, this barrier may soon be nil.

"We first demonstrated our concept by making the precursor of the anti-cancer drug taxol," said Lucks, a corresponding author on the paper. "This was a great model target to try because there's challenges and complicated chemistry, but we hope the technology we developed is general in a sense, and there's a whole array of products where you'd prefer to have microbial production."

The research was published earlier this month in the journal ACS Synthetic Biology.

Synthetic biology has been a growing field over the past several decades and has entered the public sphere with the popularization of CRSPR genome editing and development of COVID-19 vaccinations with the use of engineered RNA molecules. Now in its fifth year, the Center for Synthetic Biology at Northwestern houses professors and students across majors and schools. Lucks said the center operates unlike others he's been a part of because "it's not top-down"; students are empowered to do awesome stuff.

In fact, the recently published research was formulated at a 2016 conference that two graduate students from different labs affiliated with the Center happened to attend. Cameron Glasscock, now a postdoctoral researcher at the University of Washington, was then working toward his Ph.D. in the Lucks lab. He remembers having an idea that he could use switches to enhance the microbial production of important drug compounds. When he met Bradley Biggs, a graduate student from associate engineering professor Keith Tyo's lab, in a seminar at the conference, they spent the rest of the day conspiring in the back of the room. By the end of the day, the two had an idea.

"Cameron and I knew there wasn't a high cost to trying, even if we failed," said Biggs, an author on the paper. "Ultimately, the process was easy since our labs don't really have any barriers to collaboration."

The students worked behind the scenes with undergraduate researchers to gather preliminary data that would ultimately help shape their grant proposal, then presented the data to Lucks. Excited, Lucks immediately contacted Tyo and Danielle Tullman-Ercek, an associate professor of chemical and biological engineering in McCormick, to start collaborating on a new project.

"This was one of my more formative experiences in grad school because we were writing the first draft of pretty much everything," Glasscock said.

Creating a control switch for drug precursors
Interest in fine-tuning gene expression to improve system performance is a long-standing goal for synthetic biologists. Perfecting a mechanism to do so has applications ranging from chemical synthesis to advanced diagnostics and therapeutics, but scientists are limited by the burden and stress that these systems place on host cells.

The paper proposes a new regulatory motif called a switchable feedback promoter (SFP) that uses feedback response to control the timing and overall magnitude of reactions. SFPs are a promising route to achieving dynamic control of pathways because they react to stress and mitigate damage to the host cell.

After the lab's success making the precursor to taxol, a chemotherapy drug that takes 80 years to harvest from grown yew trees, the study goes on to replicate its results by making amorphadiene, a natural product involved in the synthesis of the antimalarial drug artemisinin. The researchers found by introducing microbial production into pathways, they were effectively able to inhibit or improve production of desired chemicals.

"There's a huge interest in taking this ability of microbes to make products sustainable, sustainably," Lucks said. "People can brew beer at large volumes. What if you could brew clothes? Or fuel? And sneakers? And you could do that sustainably and without petrochemicals."

This is where support from the lab of Tyo, also a corresponding author on the study, came in. His interest in sustainability allowed the team to apply long-term goals about the product cycle to the research. He hopes with the technology developed, he'll be able to use it in much more sophisticated contexts to turn waste from feedstock into chemicals.

For now, the researchers are hoping to help other companies and teams use the tech themselves to solve new problems and help advance questions of their own.

"If the Lucks lab was that hammer - with tools and the desire to solve this problem - my lab and Tullman-Ercek's labs were the nail - with our interest in sustainable production of chemicals using cells," Tyo said. "Now, there are more nails popping up that we aren't quite sure how to solve yet."

Volcanic eruptions deep in our oceans are capable of extremely powerful releases of energy, at a rate high enough to power the whole of the United States, according to research published today.

Eruptions from deep-sea volcanoes were long-thought to be relatively uninteresting compared with those on land. While terrestrial volcanoes often produce spectacular eruptions, dispersing volcanic ash into the environment, it was thought that deep marine eruptions only produced slow moving lava flows.

But data gathered by remotely operated vehicles deep in the North East Pacific and analysed by scientists at the University of Leeds, has revealed a link between the way ash is dispersed during submarine eruptions and the creation of large and powerful columns of heated water rising from the ocean floor, known as megaplumes.

These megaplumes contain hot chemical-rich water and act in the same way as the atmospheric plumes seen from land-based volcanoes, spreading first upwards and then outwards, carrying volcanic ash with them. The size of megaplumes is immense, with the volumes of water equivalent to forty million Olympic-sized swimming pools. They have been detected above various submarine volcanoes but their origin has remained unknown. The results of this new research show that they form rapidly during the eruption of lava.

The research was carried out by Sam Pegler, from the School of Mathematics and David Ferguson, from the School of Earth and Environment and is being published today in the journal Nature Communications.

Together they developed a mathematical model which shows how ash from these submarine eruptions spreads several kilometres from the volcano. They used the ash pattern deposited by a historic submarine eruption to reconstruct its dynamics. This showed that the rate of energy released and required to carry ash to the observed distances is extremely high - equivalent to the power used by the whole of the USA.

David Ferguson said: "The majority of Earth's volcanic activity occurs underwater, mostly at depths of several kilometres in the deep ocean but, in contrast to terrestrial volcanoes, even detecting that an eruption has occurred on the seafloor is extremely challenging. Consequently, there remains much for scientists to learn about submarine volcanism and its effects on the marine environment."

The research shows that submarine eruptions cause megaplumes to form but the release of energy is so rapid that it cannot be supplied from the erupted molten lava alone. Instead, the research concludes that submarine volcanic eruptions lead to the rapid emptying of reservoirs of hot fluids within the earth's crust. As the magma forces its way upwards towards the seafloor, it drives this hot fluid with it.

Sam Pegler added: "Our work provides evidence that megaplumes are directly linked to the eruption of lava and are responsible for transporting volcanic ash in the deep ocean. It also shows that plumes must have formed in a matter of hours, creating an immense rate of energy release.

David Ferguson adds: "Observing a submarine eruption in person remains extremely difficult but the development of instruments based on the seafloor means data can be streamed live as the activity occurs.

Efforts like these, in concert with continued mapping and sampling of the ocean floor means the volcanic character of our oceans is slowly being revealed."

Coral reefs around the world are under threat from rising sea temperatures, ocean acidification, disease and overfishing, among other reasons.

Tracking signs of stress and ill health is difficult because corals -- an animal host coexisting with algae, bacteria, viruses and fungi -- are dynamic organisms that behave differently depending on what's happening in their environment. Some scientists wonder if recording changes in coral movements over time could help with monitoring a coral reef's health.

This is not always a straightforward task. Some coral species wave and pulse in the current, but others have rock-like skeletons and may have movements that are not visible to the human eye. A new study led by University of Washington researchers borrowed image-analysis methods from engineering to spot the minute movements of a stony coral.

The team published these results April 8 in Scientific Reports.

"In mechanics, we have to be able to measure imperceptible deformations in materials and structures to understand how much load these systems are experiencing and to predict potential failures," said co-senior author Jinkyu Yang, a UW associate professor of aeronautics and astronautics. "We thought we could use these same analysis methods to study living systems, such as corals."

First the researchers needed to find the right coral species to test.

"Our analysis method easily captures surface deformation when whatever we are imaging has texture on its surface. Smooth surfaces without textures, like polished metal and glass, don't work as well," said lead author Shuaifeng Li, a UW doctoral student of aeronautics and astronautics. "Luckily, stony corals, such as Montipora capricornis, have unique patterns on their surfaces."

To get started, the researchers set up a coral photo shoot. They took 200 images of the M. capricornis specimen in a tank at a rate of 30 photos per hour in both daytime and nighttime conditions, which were controlled using different lights.

"It was challenging to keep a sharp focus on the coral due to the way the light refracted off the glass tank," Li said. "Also, we needed to pay particular attention to make sure the lighting conditions were consistent throughout the test."

Once they had acquired the pictures, the researchers used two analysis methods to search for movement. Both methods compare subsequent images in a series to the first image, playing them like a flipbook to extract changes. From here, the team could measure parameters such as pixel velocity, what parts of the coral are moving, and whether something is being compressed or stretched. The researchers also further processed the photos to be able to pull out the different types of movements occurring across the coral.

Across all measurements, the researchers saw more activities happening under the nighttime conditions. The team also saw movement for both the tissue growing on the coral's stony skeleton as well as the coral polyps, though the polyps had larger movements.

"Corals often feed more at night by expanding their polyps and using their tentacles to catch zooplankton prey, and here we are able to quantify these nocturnal movements," said co-senior author Hollie Putnam, assistant professor of biological sciences at the University of Rhode Island. "This application of engineering techniques and analyses to assess subtle and dynamic movements can transform our understanding of coral behavior and physiology, which is critical as corals are under threat from multiple stressors."

The team plans to expand this method to work on more coral species, including soft corals, which have much larger movements. Ultimately, the goal is to make this technique useful for determining potential changes in coral health under different circumstances.

"One investigation that should be considered is looking at how coral tissue motion changes upon exposure to pollutants generated by anthropogenic activities, such as chemical dispersants and oil," Yang said. "Also this method could be used to monitor coral reefs by using satellite images or pictures taken by citizen scientists."

Like a stern bodyguard for the central nervous sytem, the blood-brain barrier keeps out anything that could lead to disease and dangerous inflammation--at least when all is functioning normally.

That may not be the case in people with schizophrenia and other mental disorders, suggest new findings from a team led by researchers from the School of Veterinary Medicine, Perelman School of Medicine, and Children's Hospital of Philadelphia (CHOP). In these individuals, a more permissive barrier appears to allow the immune system to get improperly involved in the central nervous system, the researchers showed. The inflammation that arises likely contributes to the clinical manifestations of neuropsychiatric conditions.

"Our hypothesis was that, if the immune function of the blood-brain barrier is compromised, the resulting inflammation will have an impact on the central nervous system," says Jorge Iván Alvarez, an assistant professor at Penn Vet and senior author on the work, published in the journal Brain. "With that in mind, we think these findings could also be used to understand how the blood-brain barrier and neurological processes impact not only schizophrenia but mental disorders at large."

The research team pursued the study focused on a rare condition called 22q11.2 deletion syndrome (22qDS), in which people are born missing a small portion of DNA from chromosome 22. Roughly a quarter of people with this syndrome go on to develop schizophrenia. Penn and CHOP have a community of researchers who study the condition, often as a way of probing deeper into the mysteries of schizophrenia.

This disorder had not been a focus for the Alvarez lab, however, until he gave a talk at CHOP on his area of expertise--the blood-brain barrier--and was approached by an attendee afterward.

"We started talking about the fact that, in this deletion syndrome, one of the missing genes is very important for blood-brain barrier function," Alvarez says.

That attendee, Stewart Anderson of CHOP, had been studying 22qDS, and together he and Alvarez began collaborating to evaluate whether the blood-brain barrier and its effect on the immune system were playing a role in the condition.

As a first step, the group used a technique whereby stem cells from 22qDS patients diagnosed with schizophrenia, as well as healthy controls, are coaxed to develop into blood-brain barrier endothelial cells, the cells that form a tightly regulated "wall." In experiments led by Vet School doctoral student Alexis Crockett, they found that the barrier function in cells derived from 22qDS patients was more impaired than those derived from the healthy controls, which were more restrictive. They confirmed these findings in mice bred to have a version of 22qDS, finding that their blood-brain barrier was likewise leaky compared to normal mice.

The brain is typically considered "immune privileged," meaning that the surveillance carried out by immune cells and immune mediators on the central nervous system is not only regulated by the physical blockade of the blood-brain barrier but also by endothelial cells making the barrier express lower levels of immune signaling molecules.

To see if 22qDS compromised this immune privilege, the researchers again looked to patient stem cells induced to grow into blood-brain barrier cells and to their mouse model. In both cases, they observed impairments in the immune privilege properties of the barrier, with more immune cells and pro-inflammatory molecules able to cross it.

As a final validation of their findings, the researchers examined post-mortem brain tissue from three 22qDS patients and three controls. Similar to their work in cultured cells and the mouse model, they found evidence of impairment in the blood-brain barrier's physical and immune protective functions.

"This was the corroboration process, replicating all of these observations in human tissues," Alvarez says.

The work adds to a growing body of evidence suggesting that schizophrenia and certain other neuropsychiatric conditions may be in part neuroinflammatory disorders. It's also the first study to assess blood-brain barrier function in 22qDS, making an important link between neuroinflammation due to barrier dysfunction and neuropsychiatric disorders.

"Because 25% of 22q patients develop schizophrenia, it may be possible that these mechanisms taking place in 22q are applicable to idiopathic schizophrenia," Alvarez says. "And when 22q patients are studied in detail, up to 80% are found to have some form of mental disorder, so these findings may well extend to other disorders as well," including perhaps depression or autism, he says.

In future work, Alvarez and colleagues will be exploring the role of the blood-brain barrier further, narrowing in on what processes are involved in the barrier's increased permeability, including a look at astrocytes, cells that normally enhance barrier function.

Further insights into the connection between inflammation and neuropsychiatric disease, Alvarez says, may one day lead to therapies that address inflammation by manipulating the immune response.

Researchers at Beam Therapeutics have developed a redesigned base editor that shows considerable promise in directly repairing the single-base mutation that causes sickle-cell disease (SCD). Many strategies are being pursued to harness genome editing approaches including CRISPR to treat patients with SCD and related hemoglobinopathies. The most advanced method in the clinic involves targeting an upstream regulatory pathway to switch on expression of the fetal hemoglobin gene but does not target the SCD mutation directly.

Writing in the April issue of The CRISPR Journal, a team at Beam Therapeutics, led by Ian Slaymaker and Giuseppe Ciaramella, describe the successful repair of the SCD point mutation by using a redesigned base editor. The group developed a series of inlaid base editors (IBEs) by taking the deaminase portion of the base editor and inserting it into different parts of the Cas9 protein. This architecture provided a more flexible editing "window" that allowed the researchers to target the key mutation.

SCD is caused by an A-to-T mutation in the beta-globin gene resulting in a Glu-to-Val substitution. Base editing cannot reverse the SCD mutation back to the normal gene sequence but in this case, a substitution from T to G gives rise to a rare benign variant called HbG-Makassar (first described in 1970 in a young male living in Makassar, Sulawesi.)

"This paper is a great illustration of the power of CRISPR, combining the base-editing toolbox development aspect and showcasing the therapeutic potential of this modality for a broadly relevant genetic disease," commented Rodolphe Barrangou, PhD, Editor-in-Chief of The CRISPR Journal.

The study is discussed in an accompanying "First Cut" co-authored by Anna Cereseto, T.J. Cradick (Excision Therapeutics), and The CRISPR Journal Executive Editor Kevin Davies.

If the CO2 content of the atmosphere is not to increase any further, carbon dioxide must be converted into something else. However, as CO2 is a very stable molecule, this can only be done with the help of special catalysts. The main problem with such catalysts has so far been their lack of stability: after a certain time, many materials lose their catalytic properties.

At TU Wien, research is being conducted on a special class of minerals - the perovskites, which have so far been used for solar cells, as anode materials or electronic components rather than for their catalytic properties. Now scientists at TU Wien have succeeded in producing a special perovskite that is excellently suited as a catalyst for converting CO2 into other useful substances, such as synthetic fuels. The new perovskite catalyst is very stable and also relatively cheap, so it would be suitable for industrial use.

How to close the carbon cycle

"We are interested in the so-called reverse water-gas shift reaction," says Prof. Christoph Rameshan from the Institute of Materials Chemistry at TU Wien. "In this process, carbon dioxide and hydrogen are converted into water and carbon monoxide. You can then process the carbon monoxide further, for example into methanol, other chemical base materials or even into fuel."

This reaction is not new, but it has not really been implemented on an industrial scale for CO2 utilisation. It takes place at high temperatures, which contributes to the fact that catalysts quickly break down. This is a particular problem when it comes to expensive materials, such as those containing rare metals.

Christoph Rameshan and his team investigated how to tailor a material from the class of perovskites specifically for this reaction, and he was successful: "We tried out a few things and finally came up with a perovskite made of cobalt, iron, calcium and neodymium that has excellent properties," says Rameshan.

Atoms migrating through the crystal

Because of its crystal structure, the perovskite allows certain atoms to migrate through it. For example, during catalysis, cobalt atoms from the inside of the material travel towars the surface and form tiny nanoparticles there, which are then particularly chemically active. At the same time, so-called oxygen vacancies form - positions in the crystal where an oxygen atom should actually sit. It is precisely at these vacant positions that CO2 molecules can dock particularly well, in order to then be dissociated into oxygen and carbon monoxide.

"We were able to show that our perovskite is significantly more stable than other catalysts," says Christoph Rameshan. "It also has the advantage that it can be regenerated: If its catalytic activity does wane after a certain time, you can simply restore it to its original state with the help of oxygen and continue to use it."

Initial assessments show that the catalyst is also economically promising. "It is more expensive than other catalysts, but only by about a factor of three, and it is much more durable," says Rameshan. "We would now like to try to replace the neodymium with something else, which could reduce the cost even further."

The industrial plant with built-in fuel production

Theoretically, you could use such technologies to get CO2 out of the atmosphere - but to do that you would first have to concentrate the carbon dioxide, and that requires a considerable amount of energy. It is therefore more efficient to first convert CO2 where it is produced in large quantities, such as in industrial plants. "You could simply add an additional reactor to existing plants that currently emit a lot of CO2, in which the CO2 is first converted into CO and then processed further," says Christoph Rameshan. Instead of harming the climate, such an industrial plant would then generate additional benefits.