Humans are altering the diet of Tasmanian devils, which may accelerate their decline

The researchers investigated the diets of devils from habitats of differing levels of disturbance.
Photo Credit: Ariana Ananda.

New research shows how human-modified landscapes affect the diets of these marsupial scavengers.

The Tasmanian devil roams the island state of Australia as the apex predator of the land, feeding on whatever it pleases as the top dog – or the top devil. But some of these marsupial scavengers could be starting to miss out on a few items from the menu.

According to a study led by UNSW Sydney, living in human-modified landscapes could be narrowing the diet of the Tasmanian devil. The research, published recently in Scientific Reports, suggests devils have access to vastly different cuisines depending on the type of environment they live in.

“We found Tasmanian devil populations had different levels of variation in their diet depending on their habitat,” says Anna Lewis, a PhD candidate at UNSW Science and lead author of the study. “The more that habitat was impacted by humans, the more restrictive the diet became.”

A previous study by the team found most devils are individual specialists, feeding on the same food items consistently over time. But human impacts could be influencing whether they have access to their favorite foods.

“How humans change the environment impacts the animals within them,” says Professor Tracey Rogers, an ecologist at UNSW Science and senior author of the study. “Even small changes can have significant consequences for devils, so we need to be mindful of the consequences of our actions.”

Maintaining heart function in donors declared ‘dead by circulatory criteria’ could improve access to heart transplantation

More donated hearts could be suitable for transplantation if they are kept functioning within the body for a short time following the death of the donor, new research has concluded.
Photo Credit: Wagner

The organs are kept functioning by restarting local circulation to the heart, lungs and abdominal organs – but, crucially, not to the brain – of patients whose hearts have stopped beating for five minutes or longer and have been declared dead by circulatory criteria (donation after circulatory death, or DCD).

It is hoped that this technique could increase the number of usable donated hearts by as much as 30% in the future, helping address the shortage of transplant organs. In 2021, 8,409 heart transplants were reported to the Global Observatory on Donation and Transplantation (GODT) by 54 countries. This activity is in contrast with the 21,935 patients who were on a heart waiting list during the year 2021, of whom 1,511 died while waiting and many others became too sick to receive a transplant.

John Louca, a final year medical student at Gonville & Caius College, University of Cambridge, and the study’s first author, said: “Heart transplants are the last bastion for patients with end-stage heart failure. They are successful – patients who receive a transplant live on average a further 13 to 16 years. The biggest problem they face is actually getting access to a donated heart: many patients will die before an organ becomes available. That’s why we urgently need to find ways to increase the suitability of donor organs.”

Ural Scientists Design Plastics That Resist Radiation from Technology

Aleksey Korotkov tests the material for electrodynamic properties in an anechoic chamber.
Photo Credit: Rodion Narudinov

The team of scientists from the Institute of Technical Chemistry of the Ural Branch of the Russian Academy of Sciences (branch of the Perm Federal Research Centre of UB RAS) and the Ural Federal University created a composite polymer material. The new composite is made from recycled materials and has unique properties. It reflects electromagnetic waves. It is suitable for wireless systems, including radar and satellite communications systems. Such a composite (actually a plastic) can be used to make housing for devices such as smartphones. It will allow them to reduce their electromagnetic radiation. The description of the new material is published in the journal Diamond and Related Materials.

"It is extremely important that we have been able to create a new composite material from virtually recycled raw materials. The basis of the material is chopped carbon fibers, which we extracted from carbon plastics. In addition, the composition of the composite includes magnetite (it is the magnetic nanoparticles) synthesized in our laboratory. Our work can increase the attractiveness of carbon plastics processing due to the use of secondary extracted carbon fibers in the expensive technologies," says Svetlana Astafieva, the co-author of the development, the Head of the Laboratory of Structural-Chemical Modification of Polymers of the Institute of Technical Chemistry of UB RAS.

Bird Flu Associated with Hundreds of Seal Deaths in New England in 2022

A seal may contract the virus if it comes in contact with a sick bird’s excrement or water contaminated by that excrement. Seals and sea birds have environmental contact, if not direct contact, since they share the same water and shoreline.
Photo Credit: Lucía Montenegro

Researchers at Cummings School of Veterinary Medicine at Tufts University found that an outbreak of highly pathogenic avian influenza (HPAI) was associated with the deaths of more than 330 New England harbor and gray seals along the North Atlantic coast in June and July 2022, and the outbreak was connected to a wave of avian influenza in birds in the region.

The study was published on March 15 in the journal Emerging Infectious Disease.

HPAI is more commonly known as bird flu, and the H5N1 strain has been responsible for about 60 million poultry deaths in the U.S. since October 2020, with similar numbers in Europe. The virus was known to have spilled over from birds into mammals, such as minks, foxes, skunks, and bears, but those were mostly small, localized events. This study is among the first to directly connect HPAI to a larger scale mortality event in wild mammals.

The co-first authors on the paper—virologist and senior scientist Wendy Puryear and post-doctoral researcher Kaitlin Sawatzki, who both work in the Runstadler Lab at Cummings School—have been researching viruses in seals for years. They credit their findings in the new study to a unique and robust data set made possible by a collaboration with wildlife clinics and rehabilitation and response organizations in the region, in particular with Tufts Wildlife Clinic and director Maureen Murray, V03, associate clinical professor at Cummings School, and an author on the paper.

A new control switch could make RNA therapies easier to program

MIT researchers demonstrated that their RNA sensor could accurately identify cells expressing a mutated version of the p53 gene, which drives cancer development.
Image Credits: iStock, edited by MIT News
(CC BY-NC-ND 3.0)

Using an RNA sensor, MIT engineers have designed a new way to trigger cells to turn on a synthetic gene. Their approach could make it possible to create targeted therapies for cancer and other diseases, by ensuring that synthetic genes are activated only in specific cells.

The researchers demonstrated that their sensor could accurately identify cells expressing a mutated version of the p53 gene, which drives cancer development, and turn on a gene encoding a fluorescent protein only within those cells. In future work, they plan to develop sensors that would trigger production of cell-killing proteins in cancer cells, while sparing healthy cells.

“There’s growing interest in reducing off-target effects for therapeutics,” says James Collins, the Termeer Professor of Medical Engineering and Science in MIT’s Institute for Medical Engineering and Science (IMES) and Department of Biological Engineering. “With this system, we could target very specific disease cells and tissues, which opens up the possibility of identifying cancer cells and then delivering highly potent therapeutics.”

This approach could also be used to develop treatments for other diseases, including viral or bacterial infections, the researchers say.

Designing More Useful Bacteria

An illustration of viruses called phages infecting a bacterial cell.
Illustration Credit: Behnoush Hajian

In a step forward for genetic engineering and synthetic biology, researchers have modified a strain of Escherichia coli bacteria to be immune to natural viral infections while also minimizing the potential for the bacteria or their modified genes to escape into the wild.

The work promises to reduce the threats of viral contamination when harnessing bacteria to produce medicines such as insulin as well as other useful substances, such as biofuels. Currently, viruses that infect vats of bacteria can halt production, compromise drug safety, and cost millions of dollars.

“We believe we have developed the first technology to design an organism that can’t be infected by any known virus,” said the study’s first author, Akos Nyerges, research fellow in genetics in the lab of George Church in the Blavatnik Institute at Harvard Medical School and the Wyss Institute for Biologically Inspired Engineering.

“We can’t say it’s fully virus-resistant, but so far, based on extensive laboratory experiments and computational analysis, we haven’t found a virus that can break it,” Nyerges said.

The work also provides the first built-in safety measure that prevents modified genetic material from being incorporated into natural cells, he said.

Dry forests and savannas vital for Brazil’s climate goals

Cerrado savanna
Photo Credit Tim Hill

Brazil must protect and restore its dry forests and savannas to achieve its climate goals, new research shows.

Attention in Brazil and worldwide often focusses on the Amazon rainforest – ignoring damage and destruction of these seasonally dry biomes, which contain vast biodiversity and carbon stores.

The new study, led by the universities of Exeter and Campinas, says cost-effective restoration of savannas and dry forests could lock in 1.5 billion tons of carbon in 100 years.

But restoration takes time, and the researchers say protecting existing ecosystems is the best option for Brazil to reach its 2030 climate goals.

“Ongoing land-use change – especially the destruction of ecosystems to create agricultural land – makes Brazil the world’s fifth-biggest greenhouse gas emitting country,” said Dr Lucy Rowland, from Global Systems Institute at the University of Exeter.

“Denoising” a Noisy Ocean

Study lead author Ella Kim (pink helmet) helps deploy a HARP instrument package.
Photo Credit: Ana Širović

Come mating season, fishes off the California coast sing songs of love in the evenings and before sunrise. They vocalize not so much as lone crooners but in choruses, in some cases loud enough to be heard from land. It’s a technique of romance shared by frogs, insects, whales, and other animals when the time is right.

For most of these vocal arrangements, the choruses are low-frequency. They’re hard to distinguish from the sounds of ships passing in the night among others.

Biologists, however, have long been interested in listening in on them in the name of understanding fish behavior toward an ultimate goal: They can help preserve fish populations and ocean health by identifying spawning seasons to inform fisheries management.

Now scientists at Scripps Institution of Oceanography at UC San Diego and colleagues have developed a way for computers to sift through sounds collected by field acoustic recording packages known as HARPs and process them faster than even the most trained human analysts. The method represents a major advance in the field of signal processing with uses beyond marine environments.

Research team proves bacteria-killing viruses deploy genetic code-switching to deceive hosts

ORNL scientists proved the theory that bacteria-destroying viruses called bacteriophages use genetic code-switching to first infect and later overwhelm their hosts.
Illustration Credit: Andy Sproles/ORNL, U.S. Dept. of Energy

Scientists at the Department of Energy’s Oak Ridge National Laboratory have confirmed that bacteria-killing viruses called bacteriophages deploy a sneaky tactic when targeting their hosts: They use a standard genetic code when invading bacteria, then switch to an alternate code at later stages of infection.

Their study provides crucial information on the life cycle of phages. It could be a key step toward the development of new technologies such as therapeutics targeting human pathogens or methods to control phage-bacterial interactions in applications ranging from plant production to carbon sequestration.

Scientists have predicted since the mid-1990s that some organisms may use an alternate genetic code, but the process had never been observed experimentally in phages. ORNL researchers obtained the first experimental validation of this theory using uncultivated phages in human fecal samples and the lab’s high-performance mass spectrometry to reveal the intricacies of how phage proteins are expressed in the host organism. The work is detailed in Nature Communications.

For the first time, controlling the degree of twist in nanostructured particles

An array of different growth conditions, spanning from left-handed twists made with only left-handed cystine to flat pancakes made with a 50-50 mix to right-handed twists made only with right-handed cystine. The ability to control the degree of twist in a curling, nanostructured material could be a useful new tool in chemistry and machine vision.
Image Credit: Prashant Kumar, Kotov Lab, University of Michigan.

Being able to decide not only whether a micron-scale particle twists but also how much could open new avenues for machine vision and more

Micron-sized “bow ties,” self-assembled from nanoparticles, form a variety of different curling shapes that can be precisely controlled, a research team led by the University of Michigan has shown.

The development opens the way for easily producing materials that interact with twisted light, providing new tools for machine vision and producing medicines.

While biology is full of twisted structures like DNA, known as chiral structures, the degree of twist is locked in—trying to change it breaks the structure. Now, researchers can engineer the degree of twist.

Such materials could enable robots to accurately navigate complex human environments. Twisted structures would encode information in the shapes of the light waves that reflect from the surface, rather than in the 2D arrangement of symbols that comprise most human-read signs. This would take advantage of an aspect of light that humans can barely sense, known as polarization. The twisted nanostructures preferentially reflect certain kinds of circularly polarized light, a shape that twists as it moves through space.