Bird Diversity Increased in Severely Burned Forests of Southern Appalachian Mountains

Forest burned in high-severity wildfire.
Photo Credit: Chris Moorman

A new study found bird diversity increased in North Carolina mountain forest areas severely burned by wildfire in 2016, reinforcing that while wildfire can pose risks to safety and property, it can be beneficial to wildlife. The study results could help forest managers better predict bird responses to wildfire, and manage forests to benefit birds.

“It’s important for us to understand the relationships between animals and wildfire dynamics as the climate changes because predictions show more of these high-severity wildfires across the landscape in the future,” said study co-author Chris Moorman, professor of forestry and environmental resources at North Carolina State University.

Wildfires burned more than 235 square miles of forest in the southern Appalachians in the fall of 2016, following a period of dry conditions and acts of arson. In the study published in the journal Forest Ecology and Management, researchers tracked different levels of burn severity in three forest regions of the Nantahala National Forest in western North Carolina.

Astronomers discover clues about stellar ‘glitching’

Stars that experience structural "glitches" during their lifetimes may be more common than first thought.

Astronomers have found a way to peer into the physics of some of the brightest stars in the sky.

Using data from NASA’s Kepler space telescope, an international team of researchers has found new evidence that red giants, dying stars that have exhausted their supply of hydrogen and are in the final stages of stellar evolution, often experience large-scale structural variations, or what are known as “glitches” deep inside their inner core.

The stellar glitches popularized in the media have to do with a star’s rotation, but lead author Mathieu Vrard studies a different kind of defect. The glitches in this study can affect a star’s oscillations, or the frequencies and paths that sound waves travel when passing through a star.

Red clump stars, helium-core burning objects, are often used in astrophysical studies as probes of distance to measure aspects like galaxy density, and to learn more about the physical processes behind stellar chemical evolution. So, it’s vital that scientists understand why these discontinuities happen, said Vrard, a postdoctoral research associate in astronomy at the Ohio State University.

“By analyzing these variations, we can use them to obtain not only the global parameters of the star, but also information on the precise structure of those objects,” he said.

A poison helps to understand hydrogen-producing biocatalysts

Thomas Happe researches biocatalysts that can produce hydrogen in an environmentally friendly way.
 Photo Credit: RUB, Marquard

The toxic cyanide molecule attacks the enzymes, but also enables new insights into catalysis.

In nature, certain enzymes, so-called hydrogenases, are able to produce molecular hydrogen (H2) to produce. Special types of these biocatalysts, so-called [FeFe] hydrogenases, are extremely efficient and therefore of interest for bio-based hydrogen production. Although science already knows a lot about how these enzymes work, some details have not yet been fully clarified. The photobiotechnology working group at the Ruhr University Bochum around Dr. Jifu Duan and Prof. Dr. Close Thomas Happe. The researchers showed that external cyanide binds to the [FeFe] hydrogenases and inhibits hydrogen formation. They were able to demonstrate a structural change in the proton transport path that helps to understand the coupling of electron and proton transport. They report in the journal Angewandte Chemie.

Scientists use materials to make stem cells behave like human embryos

Stem cells confined in a circular shape on a soft gel display characteristic of embryonic development.
Photo Credit: University of New South Wales

A serendipitous discovery in the lab has the potential to revolutionize embryo models and targeted drug therapies.

Materials scientists at UNSW Sydney have shown that human pluripotent stem cells in a lab can initiate a process resembling the gastrulation phase – where cells begin differentiating into new cell types – much earlier than occurs in mother nature.

For an embryo developing in the womb, gastrulation occurs at day 14. But in a lab at UNSW’s Kensington campus, Scientia Associate Professor Kris Kilian oversaw an experiment where a gastrulation-like event was triggered within two days of culturing human stem cells in a unique biomaterial that, as it turned out, set the conditions to mimic this stage of embryo development.

“Gastrulation is the key step that leads to the human body plan,” says A/Prof. Kilian.

“It is the start of the process where a simple sheet of cells transforms to make up all the tissues of the body – nerves, cardiovascular and blood tissue and structural tissue like muscle and bone. But we haven’t really been able to study the process in humans because you can’t study this in the lab without taking developing embryonic tissue.

Untangling the Evolution of Complex Life

Dartmouth researchers report octopuses have high numbers of molecules linked to advanced cognition.
Photo Credit: Diane Picchiottino

Octopuses have captured the attention of scientists and the public with their remarkable intelligence, including the use of tools, engaging in creative play and problem-solving, and even escaping from aquariums. Now, their acuity may provide a critical link in understanding the evolution of complex life and cognition, including the human brain.

An international team led by researchers at Dartmouth and the Max Delbrück Center in Germany report in the journal Science Advances that octopuses are the first known invertebrates—creatures that lack a backbone and constitute roughly 95% of animal species—to contain a high number of gene-regulating molecules known as microRNAs.

The genes of two octopus species show an increase in microRNAs—which are linked to the development of advanced cells with specific functions—over evolutionary time that has so far only been found in humans, mammals, and other vertebrates.

Artificial Intelligence in Veterinary Medicine Raises Ethical Challenges

Chimmi (Chimichanga) a few hours before having his spleen removed due to a mass. Detected by Hi-Def Ultrasound by a radiologist. 7/2021
Photo Credit: Heidi-Ann Fourkiller

Use of artificial intelligence (AI) is increasing in the field of veterinary medicine, but veterinary experts caution that the rush to embrace the technology raises some ethical considerations.

“A major difference between veterinary and human medicine is that veterinarians have the ability to euthanize patients – which could be for a variety of medical and financial reasons – so the stakes of diagnoses provided by AI algorithms are very high,” says Eli Cohen, associate clinical professor of radiology at NC State’s College of Veterinary Medicine. “Human AI products have to be validated prior to coming to market, but currently there is no regulatory oversight for veterinary AI products.”

In a review for Veterinary Radiology and Ultrasound, Cohen discusses the ethical and legal questions raised by veterinary AI products currently in use. He also highlights key differences between veterinary AI and AI used by human medical doctors.

Greenland’s Glaciers Might Be Melting 100 Times As Fast As Previously Thought

A melting glacier on the coast of Greenland.
Photo Credit: Dr. Lorenz Meire, Greenland Climate Research Center.

A computer model has been created by researchers at the Oden Institute for Computational Engineering and Sciences at The University of Texas at Austin that determines the rate at which Greenland’s glacier fronts are melting.

Published in the journal Geophysical Research Letters, the model is the first designed specifically for vertical glacier fronts – where ice meets the ocean at a sharp angle. It reflects recent observations of an Alaskan glacier front melting up to 100 times as fast as previously assumed. According to the researchers, the model can be used to improve both ocean and ice sheet models, which are crucial elements of any global climate model.

“Up to now, glacier front melt models have been based on results from the Antarctic, where the system is quite different,” said lead author Kirstin Schulz, a research associate in the Oden Institute’s Computational Research in Ice and Ocean Systems Group (CRIOS). “By using our model in an ocean or climate model, we can get a much better idea of how vertical glacier fronts are melting.”

Frequent genetic cause of late-onset ataxia uncovered by a Quebec-led international collaboration

Photo Credit: whitfieldink

Discovery will improve diagnosis and open treatment possibilities for thousands of people with this debilitating neurodegenerative condition worldwide

A new study published in the New England Journal of Medicine reports the identification of a previously unknown genetic cause of a late-onset cerebellar ataxia, a discovery that will improve diagnosis and open new treatment avenues for this progressive condition.

Late-onset cerebellar ataxias (LOCA) are a heterogeneous group of neurodegenerative diseases that manifest in adulthood with unsteadiness. One to three in 100,000 people worldwide will develop a late-onset ataxia. Until recently, most patients with late-onset ataxia had remained without a genetic diagnosis.

An international team led by Dr. Bernard Brais, a neurologist and researcher at The Neuro (Montreal Neurological Institute-Hospital) of McGill University and Dr. Stephan Züchner of the University of Miami’s Miller School of Medicine, in collaboration with neurologists from the Universities of Montreal and Sherbrooke, studied a group of 66 Quebec patients from different families who had late-onset ataxia for which an underlying genetic cause had not yet been found. Using the most advanced genetic technologies, the team found that 40 (61 per cent) of the patients carried the same novel disease-causing variant in the gene FGF14, making it the most common genetic cause of late-onset ataxia in Quebec. They found that a small stretch of repetitive DNA underwent a large size increase in patients, a phenomenon known as repeat expansion.

Comet Impacts Could Bring Ingredients for Life to Europa’s Ocean

An artist's concept of a comet or asteroid impact on Jupiter's moon Europa.
Illustration Credit: NASA/JPL-Caltech

Comet strikes on Jupiter’s moon Europa could help transport critical ingredients for life found on the moon’s surface to its hidden ocean of liquid water — even if the impacts don’t punch completely through the moon’s icy shell.

The discovery comes from a study led by researchers at The University of Texas at Austin, where researchers developed a computer model to observe what happens after a comet or asteroid strikes the ice shell, which is estimated to be tens of kilometers thick.

The model shows that if an impact can make it at least halfway through the moon’s ice shell, the heated meltwater it generates will sink through the rest of the ice, bringing oxidants — a class of chemicals required for life — from the surface to the ocean, where they could help sustain any potential life in the sheltered waters.

The researchers compared the steady sinking of the massive melt chamber to a foundering ship.

NASA’s Webb Unveils Young Stars in Early Stages of Formation

Image of the Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within NGC 3324, captured by Webb’s Near-Infrared Camera (NIRCam), with compass arrows, scale bar, and color key for reference.  The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).  The scale bar is labeled in light-years, which is the distance that light travels in one Earth-year. It takes 2 years for light to travel a distance equal to the length of the bar. One light-year is equal to about 5.88 trillion miles or 9.46 trillion kilometers.  This image shows invisible near-infrared wavelengths of light that have been translated into visible-light colors. The color key shows which NIRCam filters were used when collecting the light. The color of each filter name is the visible light color used to represent the infrared light that passes through that filter.  Webb’s NIRCam was built by a team at the University of Arizona and Lockheed Martin’s Advanced Technology Center. 
Hi-Res Zoomable Image
Credits SCIENCE: Megan Reiter (Rice University) IMAGE: NASA, ESA, CSA, STScI IMAGE PROCESSING: Joseph DePasquale (STScI), Anton M. Koekemoer (STScI)

Scientists taking a “deep dive” into one of Webb’s iconic first images have discovered dozens of energetic jets and outflows from young stars previously hidden by dust clouds. The discovery marks the beginning of a new era of investigating how stars like our Sun form, and how the radiation from nearby massive stars might affect the development of planets.

The Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within the star cluster NGC 3324, has long intrigued astronomers as a hotbed for star formation. While well-studied by the Hubble Space Telescope, many details of star formation in NGC 3324 remain hidden at visible-light wavelengths. Webb is perfectly primed to tease out these long-sought-after details since it is built to detect jets and outflows seen only in the infrared at high resolution. Webb’s capabilities also allow researchers to track the movement of other features previously captured by Hubble.