. Scientific Frontline

Wednesday, October 19, 2022

Methane-Eating ‘Borgs’ Have Been Assimilating Earth’s Microbes

A digital illustration inspired by methane-eating archaea and the Borgs that assimilate them
Credit: Jenny Nuss/Berkeley Lab

In Star Trek, the Borg are a ruthless, hive-minded collective that assimilate other beings with the intent of taking over the galaxy. Here on nonfictional planet Earth, Borgs are DNA packages that could help humans fight climate change.

Last year, a team led by Jill Banfield discovered DNA structures within a methane-consuming microbe called Methanoperedens that appear to supercharge the organism’s metabolic rate. They named the genetic elements “Borgs” because the DNA within them contains genes assimilated from many organisms. In a study published today as the cover item in the journal Nature, the researchers describe the curious collection of genes within Borgs and begin to investigate the role these DNA packages play in environmental processes, such as carbon cycling.

First contact

Methanoperedens are a type of archaea (unicellular organisms that resemble bacteria but represent a distinct branch of life) that break down methane (CH4) in soils, groundwater, and the atmosphere to support cellular metabolism. Methanoperedens and other methane-consuming microbes live in diverse ecosystems around the world but are believed to be less common than microbes that use photosynthesis, oxygen, or fermentation for energy. Yet they play an outsized role in Earth system processes by removing methane – the most potent greenhouse gas – from the atmosphere. Methane traps 30 times more heat than carbon dioxide and is estimated to account for about 30 percent of human-driven global warming. The gas is emitted naturally through geological processes and by methane-generating archaea; however, industrial processes are releasing stored methane back into the atmosphere in worrying quantities.

Hands in people with diabetes more often affected by trigger finger

Mattias Rydberg, doctoral student at Lund University and resident physician at Skåne University Hospital
Source: Lund University

Locked fingers, known as trigger finger, are more common among people with diabetes than in the general population. A study led by Lund University in Sweden shows that the risk of being affected increases in the case of high blood sugar. The study has been published in Diabetes Care.

Trigger finger means that one or more fingers, often the ring finger or thumb, ends up in a bent position that is difficult to straighten out. It is due to the thickening of tendons, which bend the finger, and their connective tissue sheath, which means that the finger becomes fixed in a bent position towards the palm. It is a painful condition that can often be treated with cortisone injections, but sometimes requires surgery.

“At the hand surgery clinic, we have noted for a long time that people with diabetes, both type 1 and type 2, are more often affected by trigger finger. Over 20 percent of those who require surgery for this condition are patients who have, or will develop, diabetes,” says Mattias Rydberg, doctoral student at Lund University, resident physician at Skåne University Hospital and first author of the study.

To study whether high blood sugar (blood sugar dysregulation) increases the risk of trigger finger, the researchers examined two registers: Region Skåne’s healthcare database, which includes all diagnoses, and the Swedish national diabetes register. Between 1 and 1.5 per cent of the population are affected by trigger finger, but the diagnosis arises among 10-15 per cent of those who have diabetes, and the phenomenon appears most in the group with type 1 diabetes.

The Most Precise Accounting Yet of Dark Energy and Dark Matter

G299 was left over by a particular class of supernovas called Type Ia. 
Credit: NASA/CXC/U.Texas

 Astrophysicists have performed a powerful new analysis that places the most precise limits yet on the composition and evolution of the universe. With this analysis, dubbed Pantheon+, cosmologists find themselves at a crossroads.

Pantheon+ convincingly finds that the cosmos is composed of about two-thirds dark energy and one-third matter — mostly in the form of dark matter — and is expanding at an accelerating pace over the last several billion years. However, Pantheon+ also cements a major disagreement over the pace of that expansion that has yet to be solved.

By putting prevailing modern cosmological theories, known as the Standard Model of Cosmology, on even firmer evidentiary and statistical footing, Pantheon+ further closes the door on alternative frameworks accounting for dark energy and dark matter. Both are bedrocks of the Standard Model of Cosmology but have yet to be directly detected and rank among the model's biggest mysteries. Following through on the results of Pantheon+, researchers can now pursue more precise observational tests and hone explanations for the ostensible cosmos.

"With these Pantheon+ results, we are able to put the most precise constraints on the dynamics and history of the universe to date," says Dillon Brout, an Einstein Fellow at the Center for Astrophysics | Harvard & Smithsonian. "We've combed over the data and can now say with more confidence than ever before how the universe has evolved over the eons and that the current best theories for dark energy and dark matter hold strong."

Forgetting is natural, but learning how to learn can slow it down

Students studying at Iowa State University.
Credit: Christopher Gannon/Iowa State University

Whether you’re trying to ace a test or pick up a new hobby, Iowa State Psychology Professor Shana Carpenter says combining two strategies – spacing and retrieval practice – is key to success.

Carpenter is the lead author of a paper in Nature Reviews Psychology that examined more than 100 years of research on learning.

“The benefits of spacing and retrieval practice have been confirmed over and over in studies in labs, classrooms, workplaces, but the reason why we’re showcasing this research is because these two techniques haven’t fully caught on. If they were utilized all the time, we’d see drastic increases in learning,” said Carpenter.

In the paper, Carpenter and her co-authors describe spacing as a strategy to learn in small doses over time. It’s the opposite of cramming the night before an exam. In one study, medical students who received repeated surgery training over three weeks performed better and faster on tests 2 weeks and 1 year later compared to medical students who had the same training all on one day.

Carpenter says there isn’t a universal rule about how much time to schedule between practice sessions. But research shows returning to the material after forgetting some – but not all – of the content is effective.

Covid-19 is linked to increased degradation of connections between nerve cells in a new brain model

Postdoctoral fellow Samudyata and doctoral student Susmita Malwade.
Source: Karolinska Institutet

Researchers at Karolinska Institutet have used cellular reprogramming in a new study to create human three-dimensional brain models and infected them with SARS-CoV-2. In infected models, the brain's immune cells showed an excessive elimination of connections between the nerve cells. The gene expression of these cells also mimicked changes observed in neurodegenerative diseases. The results hope to identify new treatments for cognitive symptoms after Covid-19 infection.

Several studies have reported persistent cognitive symptoms following a covid-19 infection, but the underlying mechanisms for this are still unknown. The researchers behind the study, published in the journal Molecular Psychiatry, have created from human induced pluripotent stem cells (iPS) three-dimensional models of the brain in test tubes, so-called brain organoids. The model differs from previous organoid models in that they also contain microglia - the brain's immune cells. In the infected models, microglia regulated genes involved in phagocytosis, "cell-eating," the researchers could also see how microglia contained an increased amount of proteins from brain cell connections, so-called synapses. The developed model and results of the study can help guide future efforts to address cognitive symptoms in the aftermath of COVID-19 and other neuroinvasive viral infections.

Electric discharges on leaves during thunderstorms may impact nearby air quality

Weak electrical discharges, called corona, can form on tree leaves during thunderstorms
Credit: Pennsylvania State University

When thunderstorms rumble overhead, weak electrical discharges — called corona — can occur on tree leaves. A new study found coronas create large amounts of atmospheric chemicals that could impact air quality around forests, according to a team of Penn State scientists.

“While little is known about how widespread these discharges are, we estimate that coronas generated on trees under thunderstorms could have substantial impacts on the surrounding air,” said Jena Jenkins, a postdoctoral scholar in the Department of Meteorology and Atmospheric Science at Penn State.

Conditions during thunderstorms that produce lightning also create electric fields between clouds and the ground. Tall, sharply pointed objects, like leaves high in trees, enhance the electric field even further, and can lead to electrical breakdowns — or coronas, the scientists said.

“There are about two trillion trees in areas where thunderstorms are most likely to occur globally and there are 1,800 thunderstorms going on at any given time,” Jenkins said. “This is definitely a process that’s going on all the time and based on the calculations we’ve been able to do so far, we think this can affect air quality in and around forests and trees.”

Model calculates the energetics of piercing fangs, claws and other biological weapons

A new model can be used to calculate the forces involved when one organism stabs another with its puncturing tools. Pictured: A viper skull.
Photo by L. Brian Stauffer

Researchers have created a model that can calculate the energetics involved when one organism stabs another with its fangs, thorns, spines or other puncturing parts. Because the model can be applied to a variety of organisms, it will help scientists study and compare many types of biological puncturing tools, researchers said. It also will help engineers develop new systems to efficiently pierce materials or resist being pierced.

The new findings are reported in the Journal of the Royal Society Interface.

“The idea behind this was to come up with a quantitative framework for comparing a variety of biological puncture systems with each other,” said Philip Anderson, a University of Illinois Urbana-Champaign professor of evolution, ecology and behavior who led the research with postdoctoral researcher Bingyang Zhang. “An initial question of this research was how do we even measure these different systems to make them comparable.”

Tuesday, October 18, 2022

Algae Could be Instrumental in Making Human Exploration of Mars Possible

 A researcher working in UNLV geoscientist Elisabeth "Libby" Hausrath's lab.
Credit: University of Nevada, Las Vegas

While the world is marveling over the first images and data now coming from NASA’s Perseverance rover mission seeking signs of ancient microscopic life on Mars, a team of UNLV scientists is already hard at work on the next step: What if we could one day send humans to the Red Planet?

There’s a lot to consider when sending people, though. Human explorers, unlike their rover counterparts, require oxygen and food, for starters. It also takes about six to nine months — both ways — just in travel time. And then there’s the air itself. Martian air is roughly 98% carbon dioxide (Earth’s is a fraction of 1% for comparison) and the air temperature averages an extremely frigid -81 degrees.

It’s these challenges that UNLV geochemist and NASA Mars 2020 team scientist Libby Hausrath and postdoctoral researcher Leena Cycil, a microbial ecologist, are exploring. And a big part of the answer? Algae.

“Extremophilic algae” are types of algae known for their ability to thrive in extreme environments such as high-altitude snowy mountains or hypersaline lakes. These algae love carbon dioxide and can use it to produce oxygen. They also are edible, dense with nutrients, and grow quickly. Extremophiles’ helpful characteristics allow them to grow in some of the most inhospitable environments on Earth, possibly even in conditions similar to Mars.

New laboratory to explore the quantum mysteries of nuclear materials

INL researchers have built a laboratory around molecular beam epitaxy (MBE), a process that creates ultra-thin layers of materials with a high degree of purity and control.
Credit: Idaho National Laboratory

Replete with tunneling particles, electron wells, charmed quarks and zombie cats, quantum mechanics takes everything Sir Isaac Newton taught about physics and throws it out the window.

Every day, researchers discover new details about the laws that govern the tiniest building blocks of the universe. These details not only increase scientific understanding of quantum physics, but they also hold the potential to unlock a host of technologies, from quantum computers to lasers to next-generation solar cells.

But there’s one area that remains a mystery even in this most mysterious of sciences: the quantum mechanics of nuclear fuels.

Exploring the frontiers of quantum mechanics

Until now, most fundamental scientific research of quantum mechanics has focused on elements such as silicon because these materials are relatively inexpensive, easy to obtain and easy to work with.

Now, Idaho National Laboratory researchers are planning to explore the frontiers of quantum mechanics with a new synthesis laboratory that can work with radioactive elements such as uranium and thorium.

Ancient ocean methane not an immediate climate change threat

Researchers used a giant suction hose to collect thousands of gallons of ocean water, while on the research ship R/V Hugh Sharp. The researchers extract methane from each sample, compress the methane into cylinders, and bring the cylinders back to the lab of John Kessler, a professor of earth and environmental sciences at Rochester. From left: DongJoo Joung, a former research scientist in Kessler's lab; Kenneth Fairbarn, a research technician on the ship; Ben Riddell-Young '18; Lillian Henderson '19; and Allison Laubach '18, '19 (MS).
Credit: University of Rochester / John Kessler

New research shows reservoirs of ocean methane in mid-latitude regions will not be released to the atmosphere under warming conditions.

Deep below the ocean’s surface, the seafloor contains large quantities of naturally occurring, ice-like deposits made up of water and concentrated methane gas. For decades, climate scientists have wondered if this methane hydrate reservoir might “melt” and release massive amounts of methane to the ocean and the atmosphere as ocean temperatures warm.

New research from scientists at the University of Rochester, the US Geological Survey, and the University of California Irvine is the first to directly show that methane released from decomposing hydrates is not reaching the atmosphere.

The researchers, including John Kessler, a professor in the Department of Earth and Environmental Sciences, and DongJoo Joung, a former research scientist in Kessler’s lab and now an assistant professor in the Department of Oceanography at Pusan National University in Korea, carried out the study in mid-latitude regions—Earth’s subtropical and temperate zones.

While the stability of the methane hydrate reservoir is sensitive to changes in temperature, “in the mid-latitude regions where this study was conducted, we see no signatures of hydrate methane being emitted to the atmosphere,” says Joung, the first author of the study, published in Nature Geoscience.

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