Fruit flies use corrective movements to maintain stability after injury

Collaborators at the University of Colorado Boulder created a robotic wing made of plastic and cardboard laminate to study the mechanism by which fruit flies compensate for wing damage in flight. Photo Credit: Kaushik Jayaram

Fruit flies can quickly compensate for catastrophic wing injuries, researchers found, maintaining the same stability after losing up to 40% of a wing. This finding could inform the design of versatile robots, which face the similar challenge of having to quickly adapt to mishaps in the field.

The Penn State-led team published their results in Science Advances.

To run the experiment, researchers altered the wing length of anesthetized fruit flies, imitating an injury flying insects can sustain. They then suspended the flies in a virtual reality ring. Mimicking what flies would see when in flight, researchers played virtual imagery on tiny screens in the ring, causing the flies to move as if flying.

“We found flies compensate for their injuries by flapping the damaged wing harder and reducing the speed of the healthy one,” said corresponding author Jean-Michel Mongeau, Penn State assistant professor of mechanical engineering. “They accomplish this by modulating signals in their nervous system, allowing them to fine-tune their flight even after an injury.”

Looking at oxygen storage dynamics in three-way catalysts

Photo Credit: kalhh

In light of vehicular pollutants contributing to decreasing air quality, governments across the globe are posing stricter emission regulations for automobiles. This calls for the development of more efficient exhaust gas after-treatment systems (i.e., systems to “clean” exhaust gas before it is released into the atmosphere). The most common mode for treating exhaust emissions of gasoline-fueled internal combustion engines are three-way catalysts (TWCs) or catalytic converters. TWCs often comprise active metals such as platinum (Pt) and palladium (Pd) nanoparticles and oxygen storage materials with a high specific surface area, such as a solid solution of CeO2-ZrO2(CZ). These components can catalyze multiple oxidation and reduction reactions that can convert harmful exhaust from vehicular engines to harmless gases.

The durability, precision, and performance of a TWC is dependent on factors like the oxygen stored or removed from the bulk and surface of the oxygen storage materials. So, clearly understanding the oxygen transport and dynamics of the storage material is necessary to improve its efficiency. Unfortunately, there is a lack of techniques that can enable direct tracking of the oxygen storage process in TWCs.

‘Butterfly Bot’ is Fastest Swimming Soft Robot Yet

Inspired by the biomechanics of the manta ray, researchers at North Carolina State University have developed an energy-efficient soft robot that can swim more than four times faster than previous swimming soft robots. The robots are called “butterfly bots,” because their swimming motion resembles the way a person’s arms move when they are swimming the butterfly stroke.

“To date, swimming soft robots have not been able to swim faster than one body length per second, but marine animals – such as manta rays – are able to swim much faster, and much more efficiently,” says Jie Yin, corresponding author of a paper on the work and an associate professor of mechanical and aerospace engineering at NC State. “We wanted to draw on the biomechanics of these animals to see if we could develop faster, more energy-efficient soft robots. The prototypes we’ve developed work exceptionally well.”

The researchers developed two types of butterfly bots. One was built specifically for speed, and was able to reach average speeds of 3.74 body lengths per second. A second was designed to be highly maneuverable, capable of making sharp turns to the right or left. This maneuverable prototype was able to reach speeds of 1.7 body lengths per second.

Rapid fluctuations in oxygen levels coincided with Earth’s first mass extinction

Nevin Kozik during fieldwork to investigate how rapid changes in marine oxygen levels may have played a significant role in driving Earth’s first mass extinction.
Photo Credit: Courtesy of Nevin Kozik

Rapid changes in marine oxygen levels may have played a significant role in driving Earth’s first mass extinction, according to a new study led by Florida State University researchers.

About 443 million years ago, life on Earth was undergoing the Late Ordovician mass extinction, or LOME, which eliminated about 85% of marine species. Scientists have long studied this mass extinction and continue to investigate its possible causes, such as reduced habitat loss in a rapidly cooling world or persistent low-oxygen conditions in the oceans.

By measuring isotopes of the element thallium — which shows special sensitivity to changes in oxygen in the ancient marine environment — the research team found that previously documented patterns of this mass extinction coincided with an initial rapid decrease in marine oxygen levels followed by a rapid increase in oxygen. Their work is published online in the journal Science Advances.

“Paleontologists have noted that there were several groups of organisms, such as graptolites and brachiopods, that started to decline very early in this mass extinction interval, but we didn’t really have any good evidence of an environmental or climate signature to tie that early decline of these groups to a particular mechanism,” said co-author Seth Young, an associate professor in the Department of Earth, Ocean and Atmospheric Science. “This paper can directly link that early phase of extinction to changes in oxygen. We see a marked change in thallium isotopes at the same time these organisms start their steady decline into the main phase of the mass extinction event.”

Turning Wastewater into Fertilizer Is Feasible and Could Help to Make Agriculture More Sustainable

Photo Credit: Franck Barske

The wastewater draining from massive pools of sewage sludge has the potential to play a role in more sustainable agriculture, according to environmental engineering researchers at Drexel University. A new study, looking at a process of removing ammonia from wastewater and converting it into fertilizer, suggests that it’s not only technically viable, but also could help to reduce the environmental and energy footprint of fertilizer production — and might even provide a revenue stream for utilities and water treatment facilities.

A Sustainable Nitrogen Source

The production of nitrogen for fertilizer is an energy-intensive process and accounts for nearly 2% of global carbon dioxide emissions. In the last several years researchers have explored alternatives to the Haber-Bosch nitrogen production process, which has been the standard for more than a century. One promising possibility, recently raised by some water utility providers, is gleaning nitrogen from the waste ammonia pulled from water during treatment.

“Recovering nitrogen from wastewater would be a desirable alternative to the Haber-Bosch process because it creates a ‘circular nitrogen economy,’” said Patrick Gurian, PhD, a professor in Drexel's College of Engineering who helped lead the research, which was recently published in the journal Science of the Total Environment. “This means we are reusing existing nitrogen rather than expending energy and generating greenhouse gas to harvest nitrogen from the atmosphere, which is a more sustainable practice for agriculture and could become a source of revenue for utilities.”

Toxins force construction of ‘roads to nowhere’

This image shows the effects of the toxin VopF, depicted in green in the cell on the left, on actin filaments, depicted in magenta in both cells.
Image Credit: Elena Kudryashova

Toxins released by a type of bacteria that cause diarrheal disease hijack cell processes and force important proteins to assemble into “roads to nowhere,” redirecting the proteins away from other jobs that are key to proper cell function, a new study has found.

The affected proteins are known as actins, which are highly abundant and have multiple roles that include helping every cell unite its contents, maintain its shape, divide and migrate. Actins assemble into thread-like filaments to do certain work inside cells.

Researchers found that two toxins produced by the Vibrio genus of bacteria cause actins to start joining together into these filaments – which could be thought of as cellular highways on which cargo is delivered – at the wrong location inside cells, and headed in the wrong direction.

New carbon nanotube-based foam promises superior protection against concussions

Postdoctoral research associate Komal Chawla studies the architected vertically aligned carbon nanotube foam in the lab.
Photo Credit: Joel Hallberg

Developed by University of Wisconsin–Madison engineers, a lightweight, ultra-shock-absorbing foam could vastly improve helmets designed to protect people from strong blows.

The new material exhibits 18 times higher specific energy absorption than the foam currently used in U.S. military combat helmet liners, as well as having much greater strength and stiffness, which could allow it to provide improved impact protection.

Physical forces from an impact can inflict trauma in the brain, causing a concussion. But helmet materials that are better at absorbing and dissipating this kinetic energy before it reaches the brain could help mitigate, or even prevent, concussions and other traumatic brain injuries.

The researchers’ industry partner, helmet manufacturer Team Wendy, is experimenting with the new material in a helmet liner prototype to investigate its performance in real-world scenarios.

“This new material holds tremendous potential for energy absorption and thus impact mitigation, which in turn should significantly lower the likelihood of brain injury,” says Ramathasan Thevamaran, a UW–Madison professor of engineering physics who led the research.

The team detailed its advance in a paper recently published online in the journal Extreme Mechanics Letters.

Are Covid-19 “comas” signs of a protective hibernation state?

Caption:When the painted turtle hibernates it essentially sedates its brain to survive in its low-oxygen environment. Authors of a new paper in PNAS hypothesize that the same dynamic may be occurring in severe Covid-19 patients who underwent sedation and ventilation.
Photo Credit: Wayne

Many Covid-19 patients who have been treated for weeks or months with mechanical ventilation have been slow to regain consciousness even after being taken off sedation. A new article in the Proceedings of the National Academy of Sciences offers the hypothesis that this peculiar response could be the effect of a hibernation-like state invoked by the brain to protect cells from injury when oxygen is scarce.

A very similar kind of state, characterized by the same signature change of brain rhythms, is not only observed in cardiac arrest patients treated by chilling their body temperature, a method called “hypothermia,” but also by the painted turtle, which has evolved a form of self-sedation to contend with long periods of oxygen deprivation, or “anoxia,” when it overwinters underwater.

“We propose that hypoxia combined with certain therapeutic maneuvers may initiate an as-yet-unrecognized protective down-regulated state (PDS) in humans that results in prolonged recovery of consciousness in severe Covid-19 patients following cessation of mechanical ventilation and in post-cardiac arrest patients treated with hypothermia,” wrote authors Nicholas D. Schiff and Emery N. Brown. “In severe Covid-19 patients we postulate that the specific combination of intermittent hypoxia, severe metabolic stress and GABA-mediated sedation may provide a trigger for the PDS.”

Brain-Powered Wheelchair Shows Real-World Promise

Source/Credit: The University of Texas at Austin

In one of the first studies of its kind, several people with motor disabilities were able to operate a wheelchair that translates their thoughts into movement.

The study by researchers at The University of Texas at Austin and published today in the journal iScience is an important step forward for brain-machine interfaces — computer systems that turn mind activity into action. The concept of a thought-powered wheelchair has been studied for years, but most projects have used non-disabled subjects or stimuli that leads the device to more or less control the person rather than the other way around.

In this case, three individuals with tetraplegia, the inability to move their arms and legs due to spinal injuries, operated the wheelchair in a cluttered, natural environment to varying degrees of success. The interface recorded their brain activity, and a machine-learning algorithm translated it into commands that drove the wheelchair.

The researchers said this is a sign of future commercial viability for mind-powered wheelchairs that can assist people with limited motor function.

Researchers may have found a new biomarker for covid-19

Patients with acute COVID-19 infection have increased levels of the cytokine IL-26 in their blood.
Photo Credit: Louis Reed

Researchers at Karolinska Institutet have shown that patients with acute COVID-19 infection have increased levels of the cytokine IL-26 in their blood. Moreover, high IL-26 levels correlate with an exaggerated inflammatory response that signifies severe cases of the disease. The findings, which are presented in Frontiers in Immunology, indicate that IL-26 is a potential biomarker for severe COVID-19.

Vaccines for SARS-CoV-2 have proved effective at reducing the number of cases of severe COVID-19. However, the emergence of new viral variants, limited distribution of the vaccine and declining immunity are problems that drive scientists to find more efficacious treatments for the disease.

“We need to understand more about underlying immunological mechanisms in order to find better treatments. There is also a need for improved diagnostics in COVID 19-patients,” says Eduardo Cardenas, postdoc researcher at the Institute of Environmental Medicine, Karolinska Institutet, and principal author of the new pilot study.