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The spiral-shaped disc of stars and planets is being pulled, twisted and deformed with extreme violence by the gravitational force of a smaller galaxy - the Large Magellanic Cloud (LMC).

Scientists believe the LMC crossed the Milky Way's boundary around 700 million years ago - recent by cosmological standards - and due to its large dark matter content it strongly upset our galaxy's fabric and motion as it fell in.

The effects are still being witnessed today and should force a revision of how our galaxy evolved, astronomers say.

The LMC, now a satellite galaxy of the Milky Way, is visible as a faint cloud in the southern hemisphere's night skies - as observed by its namesake, the 16th century Portuguese explorer Ferdinand Magellan.

Previous research has revealed that the LMC, like the Milky Way, is surrounded by a halo of dark matter - elusive particles which surround galaxies and do not absorb or emit light but have dramatic gravitational effects on the movement of stars and gas in the universe.

Using a sophisticated statistical model that calculated the speed of the Milky Way's most distant stars, the University of Edinburgh team discovered how the LMC warped our galaxy's motion. The study, published in Nature Astronomy, was funded by UK Science and Technology Facilities Council (STFC).

The researchers found that the enormous attraction of the LMC's dark matter halo is pulling and twisting the Milky Way disc at 32 km/s or 115,200 kilometers per hour towards the constellation Pegasus.

To their surprise they also found that the Milky Way was not moving towards the LMC's current location, as previously thought, but towards a point in its past trajectory.

They believe this is because the LMC, powered by its massive gravitational force, is moving away from the Milky Way at the even faster speed of 370 km/s, around 1.3 million kilometres per hour.

Astronomers say it is as if the Milky Way is trying hard to hit a fast moving target, but not aiming very well.

This discovery will help scientists develop new modelling techniques that capture the strong dynamic interplay between the two galaxies.

Astronomers now intend to find out the direction from which the LMC first fell in to the Milky Way and the exact time it happened. This will reveal the amount and distribution of dark matter in the Milky Way and the LMC with unprecedented detail.

Dr Michael Petersen, lead author and Postdoctoral Research Associate, School of Physics and Astronomy, said:

"Our findings beg for a new generation of Milky Way models, to describe the evolution of our galaxy.

"We were able to show that stars at incredibly large distances, up to 300,000 light-years away, retain a memory of the Milky Way structure before the LMC fell in, and form a backdrop against which we measured the stellar disc flying through space, pulled by the gravitational force of the LMC."

Professor Jorge Peñarrubia, Personal Chair of Gravitational Dynamics, School of Physics and Astronomy, said:

"This discovery definitely breaks the spell that our galaxy is in some sort of equilibrium state. Actually, the recent infall of the LMC is causing violent perturbations onto the Milky Way.

"Understanding these may give us an unparalleled view on the distribution of dark matter in both galaxies."

Changes in climate can increase infectious disease risk in animals, researchers found -- with the possibility that these diseases could spread to humans, they warn.

The study, conducted by scientists at the University of Notre Dame, University of South Florida and University of Wisconsin-Madison, supports a phenomenon known as "thermal mismatch hypothesis," which is the idea that the greatest risk for infectious disease in cold climate-adapted animals - such as polar bears - occurs as temperatures rise, while the risk for animals living in warmer climates occurs as temperatures fall.

The hypothesis proposes that smaller organisms like pathogens function across a wider range of temperatures than larger organisms, such as hosts or animals.

"Understanding how the spread, severity and distribution of animal infectious diseases could change in the future has reached a new level of importance as a result of the global pandemic caused by SARS-CoV-2, a pathogen which appears to have originated from wildlife," said Jason Rohr, co-author of the paper published in Science and the Ludmilla F., Stephen J. and Robert T. Galla College Professor and chair of the Department of Biological Sciences at Notre Dame. "Given that the majority of emerging infectious disease events have a wildlife origin, this is yet another reason to implement mitigation strategies to reduce climate change."

The research team collected data from more than 7,000 surveys of different animal host-parasite systems across all seven continents to provide a diverse representation of animals and their pathogens in both aquatic and terrestrial environments. The study showed that pathogens found at warm locations outperform their animal hosts during cool weather as warm-adapted animals perform poorly. Similarly, pathogens found at cool locations thrive at warm temperatures, while cold-adapted animals are less tolerant of the heat.

Researchers also collected historical temperature and precipitation records at the time and location of each survey, and long-term climate data for each location to understand how temperature affected animal disease risk in different climates, and how these patterns varied depending on traits of animals and pathogens. The study also revealed that cold-blooded animals tended to offer stronger support for the thermal mismatch hypothesis than warm-blooded animals.

Next, they coupled their models to global climate change projections to predict where the risk of animal infectious diseases might change the most. The analysis suggests that global warming will likely shift infectious disease away from the equator, with decreases of animal infectious diseases in the lowland tropics and increases in the highland tropics, temperate and cooler regions of the planet.

"When each pathogen species was given equal weight, the predicted increases in infectious disease at cooler locations outweighed the decreases at warmer locations, potentially suggesting a net increase in animal infectious diseases with climate change," said Rohr, who is also an affiliated member of the Notre Dame Environmental Change Initiative and the Eck Institute for Global Health.

As for next steps, Rohr says the researchers aim to evaluate whether similar patterns exist for human and plant diseases, the latter of which could have implications for food security.

The insulation around nerve cell components in our corneas have unique properties, and little is known about them. But UConn School of Medicine neuroscience professor Royce Mohan believes his lab is on the verge of uncovering a path to better understanding that ultimately could lead to several vision-preserving advances.

Learning more about the cellular environment in the cornea, including what are known as glial cells that wrap around the nerve cell's axons, could have implications for healing after surgeries and corneal transplants, as well as nerve regeneration, not just in the eyes but potentially in other systems of the body.

In a paper published in the Journal of Neuroscience Research, lead author Paola Bargagna-Mohan, assistant professor of neuroscience, details a method of characterizing every cell in the cornea using an approach known as single-cell RNA sequence analysis to answer questions about the cornea's healing process. The study was done through a collaboration with Paul Robson, associate professor and director of single cell biology at The Jackson Laboratory for Genomic Medicine (JAX), which houses state-of-the art facilities for this type of research.

"Going in we knew there would be challenges," says Bargagna-Mohan, a recipient of a UConn Research Excellence Program award. "After several attempts, we were finally able to optimize our experimental approach to our advantage. I was extremely excited to get the funding from the UConn Vice President for Research at this critical time to drive this project."

A material known as myelin insulates axons of nerve fibers and enhances transmission of impulses among neurons. But nature has made the cornea an exception. Myelin in the cornea would interfere with light transmission. Therefore, the non-myelinating corneal Schwann cells, aptly called so because they do not produce myelin, are adapted to maintain corneal transparency, optimizing the focus of light on the retina, a crucial element of our vision.

"This class of glial cells, better known as Schwann cells, have never before been isolated and characterized," Mohan says. "So this is the first big step we took to help this field move forward in trying to repair the nerves of the cornea after surgeries, and also to understand corneal pain."The Mohan Lab's single-cell RNA sequence analysis enables access to these cells to study them to an unprecedented extent.

"All the genes that are expressed in each of the cells can be characterized," Mohan says. "But not all cells are equal, even within a certain cell type, cells are never equal. And so cells that are sitting on the peripheral side of the cornea could be very different from the cells in the middle of the cornea. And by characterizing them, we can actually interpret that information to know what genes are expressed at the corner of the eye versus the one in the middle of the eye."

Mohan, who holds the John A. and Florence Mattern Solomon Endowed Chair in Vision Biology and Eye Research, says this method already has uncovered unique genes that are not expressed in Schwann cells of other tissues, which may eventually solve the mystery of how corneal Schwann cells function without interfering with light transmission.

He has a grant application pending with the National Eye Institute to continue his study of these unique cells and their role in nerve repair and sensory function.

When it comes to corneal transplants - relatively common procedures throughout the world that would be even more common if there were enough donor corneas available to meet demand - one of the associated risks is the recipient doesn't necessarily regain full sensory function of the eye. The corneal nerves' hypersensitivity to foreign bodies is an evolutionary mechanism of injury prevention.

"If you don't get the sensory function, you may accidentally touch your eye and injure your cornea, and that could be very traumatic for someone who's just had a corneal transplant," Mohan says, noting that donor corneas generally can be preserved for several days. "We would be very interested to know how the Schwann cells survive in the existing donor tissue. Is there something we could do to enhance their survival into even higher levels? And, as well, after the operation is done?"

Sensory function is also a consideration for those who undergo laser-assisted in-situ keratomileusis. Commonly known as LASIK, it's a vision correction procedure in which the corneal axons are cut and the Schwann cells are injured.

"They also get some side effects like burning sensation, gritty feeling, and the exact molecular mechanism of what causes it and how to help the tissue heal better is not known," Mohan says.

Another condition that could benefit from a better understanding of Schwann cells' behavior is dry eye. While temporary dry eye is common, for some it can be a chronic condition in which the corneal nerves feel irritated.

"Therapeutics are discovered by knowing which genes have to be activated or which ones have gone berserk that need to be subdued," Mohan says. "What are these genes that are present in the Schwann cell doing when the cornea is injured? And from there, you ask the question, could you support nerve injury healing by either activating a gene or inhibiting something that has gone bad?"

Better understanding of the Schwann cell genes and the proteins they encode could lead to, for example, a topical drop that could support wound healing by inhibiting these targeted proteins.

Physicians and scientists are constantly on the lookout for new disease genes that can help them understand why patients have undiagnosed medical problems. Often the first clues come from genetic testing that reveals a change or mutation in a gene that they see in a child but not their parents. This is exactly what led to a new study published today in the American Journal of Human Genetics.

A multidisciplinary group including researchers at Baylor College of Medicine, Dana-Farber Cancer Institute and other institutions identified the BICRA gene as a new disease gene involved in a neurodevelopmental disorder and found evidence that BICRA functions in neural development in humans and flies. The findings provide answers to families and reveal to physicians and scientists new insights into how BICRA works, allowing for the development of individualized medical plans for patients in the future.

BICRA mutations are associated with human neurodevelopmental disorders

The first patient the researchers identified presented with undiagnosed neurological defects, including neurodevelopmental delay and other features similar, but not identical, to those observed in Coffin-Siris syndrome patients. Genetic studies revealed that the patient carried a mutation in the BICRA gene.

"With the help of the online gene-matching tool GeneMatcher, the researchers found 11 more patients with similar conditions carrying BICRA gene variants," said co-corresponding author, Dr. Hugo Bellen, Distinguished Service Professor of Molecular and Human Genetics at Baylor and member of the Jan and Dan Neurological Research Institute at Texas Children's Hospital.

In all 12 cases, the BICRA mutations were new in the patients; they were not inherited from their parents. Some of the mutations led to loss of function of the BICRA protein.

"Further analyses showed that BICRA mutations can cause disease in a dominant fashion - a mutation of only one of the two copies of the BICRA gene in the genome is sufficient to cause disease," said co-first author Dr. Scott Barish, postdoctoral associate in the Bellen lab.

This work was performed in collaboration with the lab of Dr. Cigall Kadoch at Dana-Farber Cancer Institute and Harvard Medical School.

Zebrafish and fruit flies connect BICRA to neural development

To investigate the potential connection of the BICRA gene with the features observed in the patients, the researchers turned to zebrafish and fruit flies.

"We conducted the work with zebrafish in collaboration with the Undiagnosed Disease Network Zebrafish Core run by Dr. Monte Westerfield and Dr. John Postethwait at the University of Oregon. They made a mutation in the zebrafish version of BICRA that mimicked the mutation in one of the patients," Barish said. "The zebrafish carrying the mutation showed a craniofacial defect that was similar to the facial features observed in the patients."

"In fruit flies, we showed that BICRA is expressed in the nuclei of neurons and glia, both in the larval and adult brain," said Bellen, who also is an investigator at the Howard Hughes Medical Institute at Baylor.

"Identifying BICRA as a disease gene may increase the speed at which other disease genes are identified," said co-corresponding author Dr. Daryl Scott, associate professor of molecular and human genetics at Baylor.

VIRTUAL MEETING (CST), November 22, 2020 -- The rapid spread of COVID-19 overwhelmed hospitals that were unable to contend with the increasing number of patients, many requiring ventilators and other critical care. Such conditions can put medical workers at risk. Now researchers are studying methods to increase hospital safety and efficacy during the pandemic.

A shortage of life-saving ventilators, which typically cost around $30,000 each, hit hospitals particularly hard.

"By building a simple and cheap ventilator, we can help alleviate this burden for the medical staff," said Mohamed Amine Abassi, a PhD student in fluid mechanics.

Based on a prototype designed by his advisor, engineering professor Xiaofeng Liu, Abassi spearheaded an effort with colleagues from San Diego State University and the University of California San Diego to build such a device from readily available parts--plastic tubing, pressure valves, humidifier--and an air supply. Then they tested it.

Preliminary results shared at the 73rd Annual Meeting of the American Physical Society's Division of Fluid Dynamics suggest the ventilator meets essential requirements set by the Food and Drug Administration. It is fully controllable on three parameters--air pressure, inspiration time, and Positive End Expiratory Pressure (PEEP)--with plans for more controls in the works.

Abassi and Liu foresee the ventilators assisting not just overwhelmed hospitals in the United States but also in developing countries and rural areas with limited medical infrastructure. "If they can build it at home, they can use it," said Abassi. "And you can build many of these ventilators in a very short time."

Patients on ventilators who have some pulmonary conditions relevant to COVID-19 with underlying chronic lung diseases will often receive drugs like albuterol through an endotracheal tube. This treatment relaxes the bronchial muscles and improves airflow to the constricted lung airways.

A group from Lehigh University and the University of Arkansas for Medical Sciences sought the most effective methods for administering albuterol via ventilator.

Ariel Berlinski and his group conducted aerosol characterization experiments at the University of Arkansas. Rahul Rajendran at Lehigh used the results to investigate drug delivery through computations.

"The research objective was to evaluate the efficiency of drug delivery when the nebulizer type and its placement were varied in the ventilator circuit," said Arindam Banerjee, a member of the group and a Lehigh professor of mechanical engineering and mechanics.

The researchers found that a vibrating mesh (rather than a jet) nebulizer placed on the dry side of the humidifier delivers the highest dose to the lung. Administering albuterol through intubation works most effectively for smaller particles, while oral administration is more efficient for larger particles.

"Our results are vital for mechanical ventilator based treatment," said Banerjee.

Even in optimal circumstances, healthcare workers still risk contracting COVID-19. A new respiratory apparatus could reduce exhaled aerosols, which are known to transmit the virus that causes the disease.

Researchers from Liberty University and Vapotherm wondered how common respiratory treatments would affect aerosol emissions. So they decided to test a proposed design for a PVC face mask connected to suction, adding a high-velocity nasal insufflation cannula--the kind of tubed device that delivers oxygen to the nose.

Then, with input from medical experts, they modeled a hospital room with two patients and four caregivers using highly sophisticated computational techniques. According to their model, when patients wear the new apparatus, fewer particles reach the healthcare workers.

"It represents an inexpensive way to reduce the spread of airborne contagion using supplies commonly found in hospital rooms already," said engineering PhD candidate Reid Prichard. "This will remain an important tool even after the pandemic is over."

Another group from the University of South Florida, led by mechanical engineering PhD student Anthony Perez, is investigating what happens to any aerosol contaminants that patients do emit into a hospital isolation room--and how quickly the contaminants leave the room.

"As many hospitals are reaching capacity, ensuring a hospital room is safe to enter after an aerosol-generating procedure--or after the removal of a previous patient so hygiene workers can prepare the room--requires significant down time," said Perez.

According to the researchers, the Centers for Disease Control and Prevention ventilation recommendations assume pathogen-containing aerosols are perfectly mixed within a room. Using numerical simulations, the group finds that imperfect mixing conditions significantly affect how quickly ventilation removes pathogens from a room.

"It is both surprising and somewhat concerning that the standard for air sanitization is based on what many would consider a back-of-an-envelope calculation," said Perez.

The simulations suggest aerosol contaminants can linger in "dead zones" for around 10 minutes in a typical hospital isolation room. Meanwhile, "short circuits" expel some packets of contaminants quickly before they can disperse.

"Our research illustrates the need for a more accurate, yet inexpensive, framework for the prediction of aerosol concentrations in an arbitrary hospital room, especially in assessing the level of exposure of healthcare workers," said Perez.

VIRTUAL MEETING (CST), November 22, 2020 -- Mechanical engineer Roberto Zenit spent the summer of 2019 trying to solve a problem that now plagues science departments around the world: How can hands-on fluid dynamics experiments, usually carried out in well-stocked lab rooms, be moved off campus? Since the pandemic hit, leading researchers like Zenit have found creative ways for students to explore flow at home.

Zenit's answer, ultimately, came down to pancakes. He teaches a fluid dynamics lab class at Brown University, and one experiment requires students to measure viscosity, which is often done by measuring how quickly small spheres fall through thick liquids and settle at the bottom. But Zenit realized he didn't have to do it that way. The kitchen is rich with viscous fluids, and all he had to do was pick one.

Why not pancake batter?

This fall, students in his class, wherever they were sequestered, had to mix up pancake batter, pour it on a horizontal surface, and measure how quickly the radius expanded. "By measuring the rate at which this blob grows in time you can back-calculate the viscosity," said Zenit.

Zenit described the experiment during a mini-symposium on kitchen flows at the 73rd Annual Meeting of the American Physical Society's Division of Fluid Dynamics. In addition to his viscosity-through-pancakes project, the symposium included new research on how fluids mix with each other and how they incorporate solid particles (as in batter or dough). Researchers from the University of Cambridge described new findings on hydraulic jumps--those eerily smooth circles of water, surrounded by turbulence, that form directly beneath a running kitchen faucet.

Chemical engineer Endre Mossige, a postdoctoral researcher at Stanford University, organized the symposium. "Kitchen flow experiments are so easy to do," he said. "You need so little equipment to extract such useful information about fluid dynamics."

The kitchen is a natural place to look for inspiration, said Jan Vermant, an engineer at ETH Zurich. "In the kitchen we do a lot with high-interface materials," he said. "You have to mix fluids and air and make emulsions, and work with bubbles. This is a fundamental problem of food projects, and one known by chefs all over the world."

Vermant reported on his group's recent work, which tackled a beer problem by turning it into a fluid dynamics problem. He studies thin films, and in recent research he's been studying the stability of foam in beers and breads. Beermakers, he said, check on the fermentation progress of new brews by looking at the stability of foam. But, he said, the process is very "hand-wavy." When he began looking at beer brewing through the lens of fluid dynamics, he found a rich research environment.

Beer bubbles contain a rich variety of environments: capillary flows, soap films, and protein aggregation. "Basically, they have all the mechanisms one can design as an engineer," he said. His group found, to their surprise, that even though most beers have foam, different beers have different mechanisms behind those foams. Some foams act like soap films; others develop robust protein networks at the surface.

"They each highlight different aspects of the problem nicely," said Vermant. In subsequent work, his group took a similarly close look at interfacial phenomena in breads--and similarly found a variety of behaviors. "They have this rich diversity of mechanisms to stabilize foam structures," he said.

Vermant said the work isn't just about beer and bread; it may also serve as inspiration for new materials. "We can mimic those systems and might make foams using the same principles as beer foams," he said, which could be useful for applications ranging from spray insulation to protective foams for crops.

At Brown, Zenit said not every student successfully completed the experiment. "Some of them took my advice too literally, and did it in a hot pan," he said. Cooking the pancake changed the viscosity--freezing the batter in place--which meant the students don't have usable data. (But they did have breakfast.)

He said turning to pancakes during the pandemic has opened his eyes to different ways to teach fundamental ideas like viscosity. "In the regular experiments, you drop this sphere in a container and measure it," he said. The fluid, he says, is reduced to its measurement. With batter, the student experiences the concept. "With the pancakes, you get to feel the viscosity."

VIRTUAL MEETING (CST), November 22, 2020 --They burst out of toilet bubbles, swim across drinking water, spread through coughs. Tiny infectious microbes--from the virus that causes COVID-19 to waterborne bacteria--kill millions of people around the world each year. Now engineers are studying how zinc oxide surfaces and natural hydrodynamic churning have the power to kill pathogens first.

"Bacterial contamination of common surfaces and of drinking water have been traditionally the main infection routes for transmission of serious diseases, often leading to mortality," said Abinash Tripathy, a researcher in mechanical and process engineering at ETH Zurich. "Our goal was to design a surface that can address both issues."

His group submerged clean zinc in hot water for 24 hours, which formed a zinc oxide surface covered in sharp nanoneedles. Then they introduced E. coli bacteria.

The surface kills almost all bacteria cultured on top of it very efficiently. And the biggest surprise? When sitting in contaminated water, the surface kills all waterborne E. coli within three hours--even bacteria it didn't touch.

This water disinfection at a distance works because the process generates a reactive oxygen species, which damages the cell walls of bacteria. The group from ETH Zurich, IIT Ropar India, and Empa, Switzerland, presented their initial findings at the 73rd Annual Meeting of the American Physical Society's Division of Fluid Dynamics.

In Southeast Asian and African countries where clean drinking water is scarce, current solar water disinfection methods take up to 48 hours and require a minimum intensity of sunlight. The new zinc oxide surface speeds up the disinfection process and does not need light.

"This surface can be used to disinfect water in remote areas at a very low cost," said Tripathy. "The fabrication technique is environmentally friendly, simple, and economical."

Surface and waterborne pathogens aren't the only killers. As the COVID-19 pandemic has reinforced, airborne viruses and bacteria pose a serious global challenge for disinfection.

The very droplets that carry pathogens through the air can play a role in destroying them. In the microseconds that droplets take to form, their fluids rearrange rapidly--stressing the microbes within.

"Think of a bucket with a fish in it. One imagines that if you start churning the fluid in the bucket too quickly, the fish won't be very happy," said Oliver McRae, a mechanical engineer. "It's a similar kind of thing--albeit on a much, much smaller scale--when you have, say, a pathogen in a droplet. Eventually the fluid's going to agitate too much for that bacteria or virus to survive."

McRae and a team from Boston University and the Centers for Disease Control and Prevention were studying how hydrodynamic agitation works when environmental bubbles produce droplets. After the onset of the pandemic, they started modeling droplets similar to those produced by the lungs and respiratory tract.

Using computational fluid dynamics, the team predicted how agitation works during aerosol formation. They discovered that stressors are very sensitive to droplet size. If the droplet shrinks or grows by one order of magnitude, the stressors change by two-and-a-half orders of magnitude.

The research could help explain why pathogens survive in some droplets and not others.

"Our focus has been on quantifying what the stressors are in these droplets," said McRae. "Hopefully this will be used in the future as part of a larger model to predict aerosol-based disease transmission."

Engineering a spaceship is as difficult as it sounds. Modeling plays a large role in the time and effort it takes to create spaceships and other complex engineering systems. It requires extensive physics calculations, sifting through a multitude of different models and tribal knowledge to determine singular parts of a system's design.

Dr. Zohaib Hasnain's research shows that data-driven techniques used in autonomous systems hold the potential to solve these complex modeling problems more accurately and efficiently. Applying high-functioning artificial intelligence to physics-based processes, he aims to "automate" modeling, reducing the time it takes to produce solutions and cutting production costs.

"If I am trying to undertake something along the lines of, say, designing a pencil, there's a process involved in designing that pencil," Hasnain said. "I have a certain set of steps that I would undertake given the knowledge that I have available to me based on what others have done in the past. Anything that can be described by a process or an algorithm on paper can be automated and analyzed in the context of an autonomous system."

An assistant professor in the J. Mike Walker '66 Department of Mechanical Engineering, Hasnain realized while working in the aerospace industry, the delay in projects due to modeling efforts. While conducting traditional modeling processes, scientists and researchers must create various models, many of which require testing. Additionally, filing through individual models takes far too long to produce answers. An example of a traditional modeling for space systems is computer fluid dynamics, or CFD, which uses numerical analysis to determine solutions, resulting in hefty costs computationally, and in human labor for verification.

"I always thought that there was work to be cut out because there are autonomous systems and machines that seemed capable of handling the bottleneck that is modeling," Hasnain said. "My research is a first step in understanding how and when data-driven techniques are beneficial, with the ultimate goal of taking a process that consumes months or weeks to solve, and producing a solution in hours or days."

Hasnain, accompanied by assistant professor Dr. Vinayak R. Krishnamurthy and graduate research assistant Kaustubh Tangsali, conducted a study to understand how commonly used machine-learning architectures such as convolutional neural networks (CNN) and physics informed neural networks (PINN) fare when applied to the problem of fluidic prediction. The data-driven approach uses a pre-existing modeling database to train a model over carefully controlled variations in fundamental physics of the fluid, as well as geometries over which the fluid flows. The model is then used to make a prediction. Their research found that both CNN and PINN have the potential to optimize modeling processes if targeting very specific aspects of the solution process. They are now working on a hybrid learning approach to achieve their final goal of speeding up the design process.

"We're looking at a different set of tools that will replace the old tools," said Hasnain. "We are trying to understand how these new tools behave in the context of applications traditionally governed by first principles-based solution techniques."

The researchers published their findings in the Journal of Mechanical Design. Their article, "Generalizability of Convolutional Encoder-Decoder Networks for Aerodynamic Flow-field Prediction Across Geometric and Physical-Fluidic Variations," focuses on understanding dimensional tools that have the potential of replacing modeling tools that are the current industry standard.

From the research results, Hasnain hopes to build an autonomous infrastructure that pulls from a collection of data to produce modeling solutions through hybrid machine-learning architectures. Through algorithms and pre-existing data, the infrastructure will be a modeling process that can be applied to various systems in real-life applications. Eventually, he plans to share this infrastructure for widespread, free usage.

"I would like this infrastructure to be a community initiative that's offered free to everyone," Hasnain said. "Perhaps more importantly, because it can produce near on-demand solutions as opposed to the current modeling state-of-the-art, which is extremely time-consuming."

The infrastructure is in its early stages of development. Hasnain and his fellow researchers are working to produce a prototype in the near future.

Faster, smaller, smarter and more energy-efficient chips for everything from consumer electronics to big data to brain-inspired computing could soon be on the way after engineers at The University of Texas at Austin created the smallest memory device yet. And in the process, they figured out the physics dynamic that unlocks dense memory storage capabilities for these tiny devices.

The research published recently in Nature Nanotechnology builds on a discovery from two years ago, when the researchers created what was then the thinnest memory storage device. In this new work, the researchers reduced the size even further, shrinking the cross section area down to just a single square nanometer.

Getting a handle on the physics that pack dense memory storage capability into these devices enabled the ability to make them much smaller. Defects, or holes in the material, provide the key to unlocking the high-density memory storage capability.

"When a single additional metal atom goes into that nanoscale hole and fills it, it confers some of its conductivity into the material, and this leads to a change or memory effect," said Deji Akinwande, professor in the Department of Electrical and Computer Engineering.

Though they used molybdenum disulfide - also known as MoS2 - as the primary nanomaterial in their study, the researchers think the discovery could apply to hundreds of related atomically thin materials.

The race to make smaller chips and components is all about power and convenience. With smaller processors, you can make more compact computers and phones. But shrinking down chips also decreases their energy demands and increases capacity, which means faster, smarter devices that take less power to operate.

"The results obtained in this work pave the way for developing future generation applications that are of interest to the Department of Defense, such as ultra-dense storage, neuromorphic computing systems, radio-frequency communication systems and more," said Pani Varanasi, program manager for the U.S. Army Research Office, which funded the research.

The original device - dubbed "atomristor" by the research team - was at the time the thinnest memory storage device ever recorded, with a single atomic layer of thickness. But shrinking a memory device is not just about making it thinner but also building it with a smaller cross-sectional area.

"The scientific holy grail for scaling is going down to a level where a single atom controls the memory function, and this is what we accomplished in the new study," Akinwande said.

Akinwande's device falls under the category of memristors, a popular area of memory research, centered around electrical components with the ability to modify resistance between its two terminals without a need for a third terminal in the middle known as the gate. That means they can be smaller than today's memory devices and boast more storage capacity.

This version of the memristor - developed using the advanced facilities at the Oak Ridge National Laboratory - promises capacity of about 25 terabits per square centimeter. That is 100 times higher memory density per layer compared with commercially available flash memory devices.

A gene known for helping facilitate communication between neurons in the nervous system has been discovered to be connected with Alzheimer's dementia and cognitive decline, according to a national research team led by The Jackson Laboratory and University of Maine.

Catherine Kaczorowski, associate professor and Evnin family chair in Alzheimer's research at The Jackson Laboratory (JAX), and adjunct professor with the UMaine Graduate School of Biomedical Science and Engineering (GSBSE), spearheaded a study to pinpoint the genetic mechanisms that affect resistance or vulnerability to weakening cognition and dementias, such as Alzheimer's.

Andrew Ouellette, a Ph.D student at JAX and a GSBSE NIH T32 predoctoral awardee, led the project, along with his mentor Kaczorowski and scientists from across the U.S.

By studying the memory and brain tissue from a large group of genetically diverse mice, the team found that the expression of the gene Dlgap2 is associated with the degree of memory loss in mice and risk for Alzheimer's dementia in humans. Further research will ascertain how the gene influences dementia and mental function.

Dlgap2, located in the synapses of neurons, serves to anchor critical receptors for signals between neurons required for learning and memory. When studying post-mortem human brain tissue, the team discovered low levels of Dlgap2 in people experiencing "poorer cognitive health" and "faster cognitive decline" prior to death, according to researchers.

The team's findings were published in the journal Cell Reports.

"The reason why this is so important is because a lot of research around cognitive aging and Alzheimer's has been hyper-focused on well-known risk genes like APOE and brain pathologies," Kaczorowski says. "We wanted to give ourselves the option of looking at new things people keep ignoring because they've never heard about a gene before."

Researchers found that Dlgap2 influences the formation of dendritic spines on neurons, which can affect cognitive function. Longer, thinner spines shaped like mushrooms demonstrate higher mental performance than stubbier spines in mice, Ouellette says, and decreased cognition correlates with a loss in dendritic spines.

The study serves as a springboard for additional research into Dlgap2. Ouellette will explore how it influences cognition and how it can be used in therapeutic treatment for memory loss, in part by manipulating the gene with the editing tool CRISPR. Other members of the Kaczorowski lab are studying how to regulate Dlgap2 with pharmaceuticals to help prevent cognitive decline with age.

Scientists relied on Diversity Outbred mice, a population from eight parents created by The Jackson Laboratory to better reflect genetic diversity in humans. The Dlgap2 study involved 437 mice, each one either six, 12 or 18 months old.

"It's great because you can harness the best parts of a mouse study and human society," Ouellette says. "Historically, research has been done with inbred mice with similar genetic makeups; same, similar genetic models. But clinically, humans don't work like that because they're not genetically identical."

The team performed quantitative trait loci mapping on the mouse population, examining entire genome sequences to identify genes responsible for varying cognitive function and where they occurred in the sequences. After pinpointing the connection between Dlgap2 and memory decline in mice, researchers evaluated its significance in human mental functionality using genomewide association studies for Alzheimer's dementia and studying samples of post-mortem brain tissue using imaging, microscopy and other methods.

Kaczorowski says the project relied on information and expertise from all 25 co-authors. For example, Gary Churchill, professor and Karl Gunnar Johansson chair at JAX, Elissa Chesler, professor at JAX, and postdoctoral fellow Niran Hadad provided their expertise in utilizing diversity outbred models and cross-species genomic data integration to the project. Their efforts, she says, emphasizes the importance of teamwork in advancing medical research.

"We're going to be able to contribute a lot more to human health with team science," she says.

The GSBSE and The Jackson Laboratory partner to provide cooperative Ph.D. programs that include on-site training at the laboratory in Bar Harbor. The school also partners with other academic and research institutions to provide similar learning experiences. UMaine grants the degrees for these programs.

Kaczorowski says the GSBSE's biomedical science Ph.D. program gives students hands-on learning opportunities that, like with Ouellette, can help them realize their passion and talents. Researching Dlgap2 with Kaczorowski influenced Ouellette's Ph.D. dissertation further exploring how the Dlgap2 influences cognition in animals.

"I really like this study because it's very interdisciplinary," Ouellette says, adding that it harmonizes biological and computational science. "This study set me on a path that makes me want to be a more interdisciplinary scientist."

ITHACA, N.Y. - A multi-institution team co-led by a Cornell University researcher has identified the genetic mechanisms that enable the production of a deadly toxin called Victorin - the causal agent for Victoria blight of oats, a disease that wiped out oat crops in the U.S. in the 1940s.

Victoria blight is caused by the fungus Cochliobolus victoriae, which produces the Victorin toxin, but until now no one has uncovered the genes and mechanisms involved.

"The oat varieties favored by farmers in the 1940s were resistant to Crown Rust disease, but scientists later discovered this was the very trait that made those oat varieties susceptible to Victoria blight because the Victorin toxin was targeting that specific plant protein," said co-senior author Gillian Turgeon, professor and chair of the Plant Pathology and Plant-Microbe Biology Section of the School of Integrative Plant Science, in Cornell's College of Agriculture and Life Sciences (CALS). "Unearthing the molecules involved in this fungus-plant interaction is fundamental to our understanding of how plants respond to attack by diverse microbes."

Most fungal toxins are synthesized by large, multi-functional enzymes, and the small peptides created by these enzymes include both toxins and medicines, such as the antibiotic penicillin. But Turgeon and co-author Heng Chooi, a researcher at the University of Western Australia, discovered the Victorin toxin is actually synthesized directly in the ribosome, which is an organelle in cells that makes most proteins. These small molecules produced in ribosomes are known as ribosomally synthesized and post-translationally modified peptides, or RiPPs.

This alternate mechanism for producing small peptides like Victorin - coupled with the fact that fungal genomes likely contain many RiPP-associated genes - could lead to the discovery of additional small molecules, including both new toxins and beneficial compounds.

Further, first author Simon Kessler, a doctoral student at the University of Western Australia, confirmed the enzymatic function of several Victorin genes, including a novel enzyme that converts the Victorin peptide to its active form. Surprisingly, the research team found that the Victorin genes encoding these enzymes are scattered across repetitive regions in the pathogen genome - a stark contrast to genes for most known small molecules which are typically found in compact clusters on the fungal chromosomes.

The finding could help researchers better understand the evolutionary origins of molecules like the Victorin peptides, what determines the virulence of emerging crop diseases and how to better prevent them in the future.

Turgeon notes that Victorin peptides have also been shown to interact with targets in plant cells called thioredoxins, which are also found in humans, and have potential as a site for cancer therapies.

"The discovery that these genes are not found in closely related fungi gives us insight into how virulence factors are acquired and transmitted," Turgeon said. "Our findings from this study vastly expand the potential for small molecule discovery in fungal organisms, which will increase our repertoire of knowledge about both their beneficial and harmful activities."

Humans have a longstanding relationship with the sea that spans nearly 200,000 years. Researchers have long hypothesized that places like coastlines helped people mediate global shifts between glacial and interglacial conditions and the impact that these changes had on local environments and resources needed for their survival. Coastlines were so important to early humans that they may have even provided key routes for the dispersal of people out of Africa and across the world.

Two new multidisciplinary studies published in the journals Quaternary Science Reviews and Quaternary Research document persistent human occupation along the South African eastern seaboard from 35,000 years ago to 10,000 years ago. In this remote, and largely unstudied, location -- known as the "Wild Coast" -- researchers have used a suite of cutting-edge techniques to reconstruct what life was like during this inclement time and how people survived it.

The research is being conducted by an international and interdisciplinary collaboration of scientists studying coastal adaptations, diets and mobility of hunter-gatherers across glacial and interglacial phases of the Quaternary in coastal South Africa. The research team is led by Erich Fisher, Institute of Human Origins at Arizona State University; Hayley Cawthra with the South Africa Council for Geoscience and Nelson Mandela University; Irene Esteban, University of the Witwatersrand; and Justin Pargeter, New York University.

Together, these scientists have been leading excavations at the Mpondoland coastal rock shelter site known as Waterfall Bluff for the last five years. These excavations have uncovered evidence of human occupations from the end of the last ice age, approximately 35,000 years ago, through the complex transition to the modern time, known as the Holocene. Importantly, these researchers also found human occupations from the Last Glacial Maximum, which lasted from 26,000 to 19,000 years ago.

The Last Glacial Maximum was the period of maximum global ice volume, and it affected people and places around the world. It led to the formation of the Sahara desert and caused major reductions in Amazonian rainforest. In Siberia, the expansion of polar ice caps led to drops in global sea levels, creating a land bridge that allowed people to cross in to North America.

In southern Africa, archaeological records from this globally cold and dry time are rare because there were widespread movements of people as they abandoned increasingly inhospitable regions. Yet records of coastal occupation and foraging in southern Africa are even rarer. The drops in sea level during the Last Glacial Maximum and earlier glacial periods exposed an area on the continental shelf across southern Africa nearly as large as the island of Ireland. Hunter-gatherers wanting to remain near coastlines during these times had to trek out onto the exposed continental shelf. Yet these records are gone now, either destroyed by rising sea levels during warmer interglacial periods or submerged under the sea.

The research team -- the Mpondoland Paleoclimate, Paleoenvironment, Paleoecology, and Paleoanthropology Project (P5 Project) -- has hypothesized that places with narrow continental shelfs may preserve these missing records of glacial coastal occupation and foraging.

"The narrow shelf in Mpondoland was carved when the supercontinent Gondwana broke up and the Indian Ocean opened. When this happened, places with narrow continental shelfs restricted how far and how much the coastline would have changed over time," said Hayley Cawthra.

In Mpondoland, a short section of the continental shelf is only 10 kilometers wide.

"That distance is less than how far we know past people often traveled in a day to get sea foods, meaning that no matter how much the sea levels dropped anytime in the past, the coastline was always accessible from the archaeological sites we have found on the modern Mpondoland coastline. It means that past people always had access to the sea, and we can see what they were doing because the evidence is still preserved today," said Erich Fisher.

The oldest record of coastal foraging, which has also been found in southern Africa, shows that people relied on coastlines for food, water and move favorable living conditions over tens of thousands of years.

In the study published in the journal Quaternary Research, led by Erich Fisher, a multidisciplinary team of researchers documents the first direct evidence of coastal foraging in Africa during a glacial maximum and across a glacial/interglacial transition.

According to Fisher, "The work we are doing in Mpondoland is the latest in a long line of international and multidisciplinary research in South Africa revealing fantastic insights into human adaptations that often occurred at or near coastlines. Yet until now, no one had any idea what people were doing at the coast during glacial periods in southern Africa. Our records finally start to fill in these longstanding gaps and reveal a rich, but not exclusive, focus on the sea. Interestingly, we think it may have been the centralized location between land and sea and their plant and animal resources that attracted people and supported them amid repeated climatic and environmental variability."

To date this evidence, P5 researchers collaborated with South Africa's iThemba LABS and researchers at the Centre for Archaeological Science of the University of Wollongong to develop one of the highest-resolution chronologies at a southern Africa Late Pleistocene site, showing persistent human occupation and coastal resource use at Waterfall Bluff from 35,000 years ago to 10,000 years ago. This evidence, in the form of marine fish and shellfish remains, shows that prehistoric people repeatedly sought out dense and predictable seafoods.

This finding complements the results of a companion study published in the journal Quaternary Science Reviews, where paleobotanists and paleoclimatologists, led by Irene Esteban, used different lines of evidence to investigate interactions between prehistoric people's plant-gathering strategies and climate and environmental changes over the last glacial/interglacial phase. This is the first multiproxy study in South Africa that combines preserved plant pollen, plant phytoliths, macro botanical remains (charcoal and plant fragments) and plant wax carbon and hydrogen isotopes from the same archaeological archive.

According to Irene Esteban, "It is not common to find such good preservation of different botanical remains, both of organic and inorganic origin, in the archaeological record."

Each one of these records preserves a slightly different window to the past. It let the researchers compare different records to study how each one formed and what they represented, both individually and together.

"Ultimately," said Esteban, "it allowed us to study interactions between hunter-gatherer plant-gathering strategies and environmental changes across a glacial-interglacial transition."

Today, Mpondoland is characterized by afrotemperate and coastal forests as well as open woodlands that are interspersed with grasslands and wetlands. Each of these vegetation types supports different plant and animal resources. One of the key findings of this study is that these vegetation types persisted across glacial and interglacial periods albeit in varying amounts due to changes in sea levels, rainfall and temperature. The implication is that people living in Mpondoland in the past had access to an ever present and diverse suite of resources that let them survive here when they couldn't in many other places across Africa.

Importantly, this study showed that people who lived at Waterfall Bluff collected wood from coastal vegetation communities during both glacial and interglacial phases. It is another link to the coastline for the people living at Waterfall Bluff during the Last Glacial Maximum. In fact, the exceptional quality of the archaeological and paleoenvironmental records demonstrates that those hunter-gatherers targeted different, but specific, coastal ecological niches all the while collecting terrestrial plant and animal resources from throughout the broader landscape and maintaining links to highland locales inland.

"The rich and diverse resource bases targeted by Mpondoland's prehistoric hunter-gatherers speaks to our species' unique generalist-specialist adaptations," said Justin Pargeter. "These adaptions were key to our species ability to survive wide climate and environmental fluctuations while maintaining long-distance cultural and genetic connections."

Together, these papers enrich our understanding about the adaptive strategies of people facing widespread climatic and environmental changes. They also provide a complementary perspective on hunter-gatherer behavioral responses to environmental shifts that is often biased by ethnographic research on African hunter-gatherers living in more marginal environments. In the case of Mpondoland, it is now evident that at least some people sought out the coast -- probably because it provided centralized access to fresh water as well as both terrestrial and marine plant and animal resources, which supported their daily survival.

According to Esteban and Fisher, "These studies are just a drop in the ocean compared to the richness of the archaeological record we already know is preserved in Mpondoland. We have high expectations about what else we will discover there with our colleagues in South Africa and abroad when we can get back to the field safely in this post-COVID world."

VIRTUAL MEETING (CST), November 22, 2020 -- Swelling is one of the most dangerous and immediate consequences of a brain injury or stroke. Doctors have long known about the dangers of swelling, which has traditionally been blamed on ruptured blood vessels. New research suggests the brain's other plumbing system, the one that circulates cerebrospinal fluid (CSF), may play an underappreciated role in both good health and response to injury.

Douglas Kelley, a mechanical engineer at the University of Rochester who uses fluid dynamics to probe the inner workings of the brain, teamed up with Rochester neuroscientist Maiken Nedergaard to demonstrate the early swelling immediately after an injury or stroke results not from blood, but from an inrush of CSF. The blood flows in later through tears in the blood-brain barrier.

"There is this whole other fluid transport system beyond blood," said Kelley, who presented the work at the 73rd Annual Meeting of the American Physical Society's Division of Fluid Dynamics. "It matters for disease, and for pathology, and it matters for drug delivery."

Researchers had assumed that CSF only flowed around brain tissue. Then, in 2012, Nedergaard's group published evidence pointing to the existence of CSF pathways through the brain. Their findings suggested that during sleep, CSF flows along these glymphatic pathways and rinses away cellular debris, like the amyloid-beta and tau proteins that accumulate and have been linked to Alzheimer's disease. Since then, research into the fluid dynamics of CSF has emerged as its own subfield that can provide new insights to biologists and neuroscientists.

"Having numbers on things helps you make better predictions," said Kelley. "They let us make predictions about the speed of flow, and when flow is more important, and when diffusion is more important. We can make better predictions now than anybody could three or four years ago."

Saikat Mukherjee, a postdoctoral researcher at the University of Minnesota, Twin Cities, noted that researchers still disagree about whether or not CSF enters brain tissue. If it doesn't, then the brain primarily relies on diffusion to clear toxic proteins. If CSF does seep into the brain tissue, even a little, then advection--the clearing of material by fluid flow--could help significantly with the cleanup.

The difference may be huge. "Toxic proteins get released from the brains and don't just sit there," said Mukherjee. "They aggregate into higher and higher molecular weight proteins." Mukherjee's work suggests that diffusion is not as efficient in clearing larger aggregates, while advection may clear proteins of any size. If advection does turn out to play a role, he said, then perhaps that knowledge could be harnessed to develop new neurodegenerative disease treatments that better clear protein aggregates.

Mukherjee and his colleagues are currently studying clinical data on plaque buildup in the brain to see how well it matches their simulations. They're also reviewing findings from studies investigating the clearance of toxic proteins during the sleep-wake cycle.

Ultimately, said Mukherjee, using fluid dynamics to study brain fluids points opens up two clear pathways of research. First, it can help neuroscientists better understand how the body gets rid of cellular debris--and what happens, from a physics point of view, when that system breaks down. Second, it could lead to insights on more fundamental questions about fluid dynamics and reaction-diffusion transport mechanisms in the brain.

"It lets us look at new physics that no one else has looked at yet," said Mukherjee.

In a recent article in The Quarterly Review of Biology, "Beyond Equilibria: The Neglected Role of History in Ecology and Evolution," author Hamish G. Spencer argues for a revitalized view of history. This historical view is a response to current research in the field of ecology and evolution, which is dominated by an ahistorical view of dynamic systems. In this ahistorical view, mathematical models are extensively used to describe and analyze systems at an equilibrium. Such equilibrium-focused analyses are currently privileged, because they allow researchers to generalize their models of a system: that is, these equilibrium-focused analyses enable researchers "to distill the essence of a system into principles that apply elsewhere." While the article acknowledges the value of equilibrium-focused analyses, such analyses tend to unfairly evaluate biological history as dependent on non-generalizable particularities. As a result, current research in ecology and valuate tends to avoid historical forms of analysis.

In response to this common assumption about history, the article argues that there are at least nine "flavors" or understandings of history. These understandings of history, in turn, allow researchers to generalize their findings and the observe scientific laws at work. These nine understandings of history are as follows: (1) history as contingency, (2) history as chance, (3) history as chaos, (4) history as capriciousness, (5) history as approach, (6) history as constraint, (7) history as construction, (8) history as turnover, and (9) history as template.

The first five understandings of history are closely related, because they analyze random co-occurrence and unpredictability. First, in an understanding of history as contingency, researchers can approach a system as an "occurrence of events conditional on a vast array of properties." Second, by incorporating history as contingency, researchers are better equipped in analyzing empirical observation over time, such as how fish of different sizes distribute themselves in an environment with a limited amount of nutrients. This analysis of history of contingency is closely tied to a second understanding of history as chance, or stochasticity, because biological systems are subject to random chance. Subsequently, in understanding history of chaos, researchers can analyze a system as incorporating unexpected deterministic behavior, which can be analyzed by mathematical models. Finally, in an understanding of history as capriciousness, ecologists can analyze a system beyond adherence to principles of statistically reliability. For instance, a larger sample size might not result in a mean that is closer to the true mean of a given distribution - a phenomenon that falls under the category of capriciousness.

The next four conceptualizations of history offer a further critique of equilibrium-focused analyses in ecology and evolution. First, in an understanding of history as an approach, researchers can analyze a system as approaching a state of equilibrium, but not at the state of equilibrium itself. Second, in an understanding of history as constraint, researchers can analyze the dynamics of a system as being constrained by "what has already taken place to build the system," such as the reduction of genome size among a particular species living in a specialized environment. Third, in an understanding of history as construction, researchers can begin by understanding that "equilibrial properties are an incomplete--and sometimes misleading--summary of the way the system behaves." Fourth, in understanding history as turnover, researchers can understand a system as perpetually being influenced by new actors, thereby questioning whether a "biological system is (or can ever be) at equilibrium."

Finally, in understanding history as a template, researchers can understand the historical contingencies of a system for both scientific analysis and modeling: for instance, phylogenetic models can be understood as "providing evolution with a template on which to work."

In conclusion, the article suggests that these "flavors" of history can be simultaneously at work in a given biological system. Rather than treating history in ecology and evolution as a set of non-generalizable particulars, researchers can further their analysis of biological systems by "teasing out the many roles various different flavors of history play in nature."

Bulbs of the plant known as Lu Bei (Fritallaria delavayi) have been used in Chinese medicine for more than two thousand years. Now, researchers reporting November 20 in the journal Current Biology have found that, in places where the herb is harvested more, the plant has evolved to blend in better with the background, making them harder for people to find. As a result, the plant varies in color from brown or grey to green, depending on whether it lives in a place that is frequented by human collectors or not.

"We've found that human harvesting of a traditional medicine plant has led to the evolution of camouflage by the plants, to evade detection by collectors," said Martin Stevens of University of Exeter. "And that camouflage is better in locations where collection intensity has been higher."

First author of the new study Yang Niu, Kunming Institute of Botany, Chinese Academy of Sciences, had been studying the evolution of alpine plants for years. He and his colleagues had noticed that the color of F. delavayi showed obvious variation among populations. They also knew it had a long history of use in traditional medicine. Could human harvesting be responsible for those differences in color they were seeing?

It appears that the answer is yes. The researchers found that the degree to which the plants' color matches its mountainous background is associated with estimates of how heavily they are harvested in particular places. Where they are heavily collected, the plants are camouflaged and therefore more cryptic.

To confirm that the plant colors influenced the ability of people to find them, the researchers developed an online citizen science experiment "Spot the Fritillaria." People were asked to spot the plants as quickly as they could. Not surprisingly, those plants that more closely matched the background took longer for people to find.

While it's possible that other animals could exert similar pressures, the researchers say they don't think that's likely. There's no evidence that the plants are a popular food item for other animals living in the area. The plants also produce chemicals that are known to deter rodents. Ironically, it is those same compounds that make them attractive to people as a medicinal herb.

For the plant, the camouflage may have downsides, which the researchers hope to explore in future studies. "In heavily collected populations, camouflage in flowers may weaken their attractiveness to pollinators such as bumblebees," Niu said. "We aim to find out how the plants deal with this problem."

Stevens says his team is "further exploring how animals and plants are being affected by human actions, including how their defensive behaviors and coloration are being influenced by selection pressure and stresses imposed by humans, from noise pollution to climate change."