The 'brown food web': dead vegetation plays essential role in desert ecosystems

Researchers from UNSW say these insights could be used by the conservation managers of arid ecosystems in Australia.
Resized Image using AI by SFLORG
Photo Credit: Prof. Mike Letnic.

A reduction in decaying vegetation can have significant impacts on the desert food chain, UNSW scientists have found.  

It’s well understood that overgrazing by herbivores like kangaroos can change ecosystems dramatically, but the impact excessive grazing has on the cover of dead vegetation – and cascading effects on small vertebrates like lizards, desert frogs and dunnarts – hasn’t been extensively studied.

Now, scientists at UNSW Sydney have shown that overgrazing can disrupt the desert food webs that exist between dead plant material, termites and animals that rely on termites as their main food source. This latest discovery has important implications for the conservation of biodiversity in arid Australia.

Researchers from the School of Biological, Earth & Environmental Sciences carried out field work in the arid region of South Australia and published their findings in the journal Ecosystems. 

Children have not recovered learning lost during the COVID-19 pandemic

Learning online: 'We find a substantial overall learning deficit…which arose early in the pandemic and persists over time… The pooled effect…implies that students lost out on about 35% of what they would have learned in a normal school year…This confirms initial concerns the pandemic would cause substantial harm to student learning.'
Photo Credit: Amr

Each year during the pandemic, school children lost one third of what they would have learned – and this has still not been recovered, according to a study published today in Human Nature Behaviour.

According to the paper, A systematic review and meta-analysis of the impact of the COVID-19 pandemic on learning, ‘We find a substantial overall learning deficit…which arose early in the pandemic and persists over time… The pooled effect…implies that students lost out on about 35% of what they would have learned in a normal school year…This confirms initial concerns the pandemic would cause substantial harm to student learning.’

In particular, the paper finds, Math learning has been affected as well as children from lower income groups, ‘The pandemic has exacerbated educational inequalities between children from different socio-economic backgrounds, which were already large before the pandemic.’

Second Hypersonic Air-Breathing Weapon Concept Launched From B-52 Accomplishes "All Test Objectives"

Artist’s concept of the DARPA and Lockheed Martin Hypersonic Air Breathing Weapon Concept (HAWC).
Illustration Credit: Lockheed Martin

DARPA's Latest HAWC Flight Test Demonstrates Mature, Affordable Hypersonic Systems Design and Manufacturing Techniques

The Defense Advanced Research Projects Agency (DARPA), Air Force Research Lab (AFRL), Lockheed Martin and Aerojet Rocketdyne team accomplished their primary objectives during its second Hypersonic Air-breathing Weapon Concept (HAWC) flight test doubling the amount of scramjet powered vehicle data.

Launching from a B-52, the HAWC system's first stage boosted it to the targeted engine ignition envelope, where the Aerojet Rocketdyne scramjet engine fired and accelerated the system to speeds in excess of Mach 5. The system performed as predicted travelling more than 300 nautical miles and reaching altitudes above 60,000 feet. 

New type of solar cell is being tested in space

Magnus Borgström Professor, Solid State Physics Lund University
Photo Credit: Lund University

Physics researchers at Lund University in Sweden recently succeeded in constructing small solar radiation-collecting antennas – nanowires – using three different materials that are a better match for the solar spectrum compared with today’s silicon solar cells. As the nanowires are light and require little material per unit of area, they are now to be installed for tests on satellites, which are powered by solar cells and where efficiency, in combination with low weight, is the most important factor. The new solar cells were sent into space a few days ago.

A group of nanoengineering researchers at Lund University working on solar cells made a breakthrough last year when they succeeded in building photovoltaic nanowires with three different band gaps. This, in other words, means that one and the same nanowire consists of three different materials that react to different parts of solar light. The results have been published in Materials Today Energy and subsequently in more detail in Nano Research.

“The big challenge was to get the current to transfer between the materials. It took more than ten years, but it worked in the end,” says Magnus Borgström, professor of solid-state physics, who wrote the articles with the then doctoral student Lukas Hrachowina.

Earth likely to cross critical climate thresholds even if emissions decline

Already, the world is 1.1 degrees Celsius hotter on average than it was before fossil fuel combustion took off in the 1800s. More extreme rainfall and flooding are among the litany of impacts from that warming.
Photo Credit: Chris Gallagher

Artificial intelligence provides new evidence our planet will cross the global warming threshold of 1.5 degrees Celsius within 10 to 15 years. Even with low emissions, we could see 2 C of warming. But a future with less warming remains within reach.

A new study has found that emission goals designed to achieve the world’s most ambitious climate target – 1.5 degrees Celsius above pre-industrial levels – may in fact be required to avoid more extreme climate change of 2 degrees Celsius.

The study, published Jan. 30 in Proceedings of the National Academy of Sciences, provides new evidence that global warming is on track to reach 1.5 degrees Celsius (2.7 Fahrenheit) above pre-industrial averages in the early 2030s, regardless of how much greenhouse gas emissions rise or fall in the coming decade.

The new “time to threshold” estimate results from an analysis that employs artificial intelligence to predict climate change using recent temperature observations from around the world.

Marburg vaccine shows promising results in first-in-human study

Colorized scanning electron micrograph of Marburg virus particles (blue) both budding and attached to the surface of infected VERO E6 cells (orange).
Image Credit: National Institute of Allergy and Infectious Diseases

A newly published paper in The Lancet shows that an experimental vaccine against Marburg virus (MARV) was safe and induced an immune response in a small, first-in-human clinical trial. The vaccine, developed by researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, could someday be an important tool to respond to Marburg virus outbreaks.

This first-in-human, Phase 1 study tested an experimental MARV vaccine candidate, known as cAd3-Marburg, which was developed at NIAID’s Vaccine Research Center (VRC). This vaccine uses a modified chimpanzee adenovirus called cAd3, which can no longer replicate or infect cells, and displays a glycoprotein found on the surface of MARV to induce immune responses against the virus. The cAd3 vaccine platform demonstrated a good safety profile in prior clinical trials when used in investigational Ebola virus and Sudan virus vaccines developed by the VRC.

Mating causes ‘jet lag’ in female fruit flies, changing behavior

A seminal fluid protein transferred from male to female fruit flies during mating changes the expression of genes related to the fly’s circadian clock, Cornell research has found.
Photo Credit: Erik Karits

A seminal fluid protein transferred from male to female fruit flies during mating changes the expression of genes related to the fly’s circadian clock, an innovative technique has revealed.

The finding, published in the Proceedings of the National Academy of Sciences, could help explain how this protein, called sex peptide, alters the female’s behavior.

Post-mating, sex peptide has been shown to elicit increased egg-laying, aggression, activity and feeding, while reducing sleep and interest in mating in previously unmated females.

“Flies like to eat at certain times of day,” said Mariana Wolfner ’74, professor of molecular biology and genetics and a Stephen H. Weiss Presidential Fellow in the College of Arts and Sciences, and one of the paper’s senior authors. “They sleep at certain times, and the circadian clock machinery controls when flies are likely to do these things.

Climate Change May Cut U.S. Forest Inventory by a Fifth This Century

Mountain forests.
Photo Credit  Alek Kalinowsk

A study led by a North Carolina State University researcher found that under more severe climate warming scenarios, the inventory of trees used for timber in the continental United States could decline by as much as 23% by 2100. The largest inventory losses would occur in two of the leading timber regions in the U.S., which are both in the South.

Researchers say their findings show modest impacts on forest product prices through the end of the century, but suggest bigger impacts in terms of storing carbon in U.S. forests. Two-thirds of U.S. forests are classified as timberlands.

“We already see some inventory decline at baseline in our analysis, but relative to that, you could lose, additionally, as much as 23% of the U.S. forest inventory,” said the study’s lead author Justin Baker, associate professor of forestry and environmental resources at North Carolina State University. “That’s a pretty dramatic change in standing forests.”

Boeing Awarded U.S. Air Force Contract for 15 KC-46A Tankers

KC-46A Pegasus tanker
Photo Credit: Boeing

The U.S. Air Force has awarded Boeing a $2.3 billion contract for the ninth production lot of 15 KC-46A Pegasus tanker aircraft, expanding its fleet of the world’s most advanced multi-mission aerial refueler. To date, 128 KC-46A Pegasus are on contract with the U.S. Air Force, with 68 delivered and operationally deployed worldwide.

“The combat-ready KC-46A is transforming the role of the tanker for the 21st century,” said James Burgess, vice president and KC-46 program manager. “We’re proud to work side-by-side with the Air Force ensuring the Pegasus provides unmatched capabilities and continues to evolve for the U.S. and its allies’ global mission needs.”

The KC-46A Pegasus delivers crucial fuel and data for the fleet, as well as cargo, personnel and aeromedical transportation for joint force rapid mobility, global reach and agile combat employment.

Researchers can ‘see’ crystals perform their dance moves

Wenbin Li (left) and Aditya Mohite.
Photo Credit: Jeff Fitlow/Rice University

Rice University researchers already knew the atoms in perovskites react favorably to light. Now they can see precisely how those atoms move.

A breakthrough in visualization supports their efforts to squeeze every possible drop of utility out of perovskite-based materials, including solar cells, a long-standing project that only recently yielded an advance to make the devices far more durable.

A study published in Nature Physics details the first direct measurement of structural dynamics under light-induced excitation in 2D perovskites. Perovskites are layered materials that have well-ordered crystal lattices. They are highly efficient harvesters of light that are being explored for use as solar cells, photodetectors, photocatalysts, light-emitting diodes, quantum emitters and more.

“The next frontier in light-to-energy conversion devices is harvesting hot carriers,” said Rice University’s Aditya Mohite, a corresponding author of the study. “Studies have shown that hot carriers in perovskite can live up to 10-100 times longer than in classical semiconductors. However, the mechanisms and design principles for the energy transfer and how they interact with the lattice are not understood.”