Study links length of REM sleep to body temperature

Credit: Lancet Neurology

Warm-blooded animal groups with higher body temperatures have lower amounts of rapid eye movement (REM) sleep, while those with lower body temperatures have more REM sleep, according to new research from UCLA professor Jerome Siegel, who said his study suggests that REM sleep acts like a “thermostatically controlled brain heater.”

The study in Lancet Neurology suggests a previously unobserved relationship between body temperature and REM sleep, a period of sleep when the brain is highly active, said Siegel, who directs the Center for Sleep Research at the Jane and Terry Semel Institute for Neuroscience and Human Behavior at UCLA.

Birds have the highest body temperature of any warm-blooded, or homeotherm, animal group at 41 degrees while getting the least REM sleep at 0.7 hours per day. That’s followed by humans and other placental mammals (37 degrees, 2 hours of REM sleep), marsupials (35 degrees, 4.4 hours of REM sleep), and monotremes (31 degrees, 7.5 hours of REM sleep).

Physicists generate new nanoscale spin waves

Illustration of the experiment
Photo: Dreyer et al, Nature Communications (CC-BY-SA 4.0)

Strong alternating magnetic fields can be used to generate a new type of spin wave that was previously just theoretically predicted. This was achieved for the first time by a team of physicists from Martin Luther University Halle-Wittenberg (MLU). They report on their work in the scientific journal "Nature Communications" and provide the first microscopic images of these spin waves.

The basic idea of spintronics is to use a special property of electrons - spin - for various electronic applications such as data and information technology. Spin is the intrinsic angular momentum of electrons that produces a magnetic moment. Coupling these magnetic moments creates the magnetism that could ultimately be used in information processing. When these coupled magnetic moments are locally excited by a magnetic field pulse, this dynamic can spread like waves throughout the material. These are referred to as spin waves or magnons.

A special type of those waves is at the heart of the work of the physicists from Halle. Normally, the non-linear excitation of magnons produces integers of the output frequency - 1,000 megahertz becomes 2,000 or 3,000, for example. "So far, it was only theoretically predicted that non-linear processes can generate spin waves at higher half-integer multiples of the excitation frequency," explains Professor Georg Woltersdorf from the Institute of Physics at MLU. The team has now been able to show experimentally which conditions are needed in order to generate these waves and to control their phase. Phase is the state of the oscillation of a wave at a certain point and time. "We are the first to confirm these excitations in experiments and have even been able to map them," says Woltersdorf.

Airway antibodies protect against omicron infection

Charlotte Thålin, assistant chief physician and associate professor at Department of Clinical Sciences, Danderyds Hospital, Karolinska Institutet, led the study.
Credit: Ludvig Costyal

High levels of antibodies in the airways reduce the risk of being infected by omicron, but many do not receive measurable antibody levels in the airways desperate three doses of SARS-Cov-2 vaccine. It shows a new study published in The New England Journal of Medicine by researchers at Karolinska Institutet and Danderyds Hospital.

The COMMUNITY study started in the spring of 2020 with a provincial collection of 2,149 employees at Danderyds Hospital. The study participants and their immune response to the coronavirus sars-cov-2 have since followed up every four months. At the beginning of 2022, a study was conducted in which 338 employees who received three doses of vaccine were regularly screened for SARS-Cov-2 infection. Of those who were not infected at the start of the study, sixth participants (57 people) were infected with omics during the course of the study. This allowed the research team to investigate what protects against infection and what the immune response after omicron infection looks like.

Researchers Discover First Pair of Mated Blue Crabs in Great Bay

UNH doctoral student Kelsey Meyer with large male blue crab in Great Bay Estuary.
Courtesy photo University of New Hampshire

Researchers at the University of New Hampshire have documented the first discovery of a pair of recently mated blue crabs in Great Bay Estuary (GBE), a finding that is expected to have serious impacts on the estuary’s ecosystem, particularly its fragile oyster population. Blue crabs have been captured in GBE since 2012 but this is the first-time researchers have found compelling evidence that the crabs are actually mating.

“The arrival of blue crabs capable of creating a sustained population poses a new threat to oysters and other native GBE species,” said Bonnie Brown, professor, and chair of the department of biological sciences.

Doctoral student Alyssa Stasse and technician Emily Williams were checking traps set out by doctoral student Kelsey Meyer, who is monitoring the estuary’s invasive green crab population, when they found the two blue crabs and the mating proof: the female, which had recently molted, had distended turgid seminal receptacles with large sperm plugs, clear evidence of crustacean copulation.

First light at the most powerful laser in the US

The laser that will be the most powerful in the United States is preparing to send its first pulses into an experimental target at the University of Michigan.

Funded by the National Science Foundation, it will be a destination for researchers studying extreme plasmas around the U.S. and internationally.

Called ZEUS, the Zetawatt-Equivalent Ultrashort pulse laser System, it will explore the physics of the quantum universe as well as outer space, and it is expected to contribute to new technologies in medicine, electronics and national security.

“ZEUS will be the highest peak power laser in the U.S. and among the most powerful laser systems in the world. We’re looking forward to growing the research community and bringing in people with new ideas for experiments and applications,” said Karl Krushelnick, director of the Center for Ultrafast Optical Science, which houses ZEUS, and the Henry J. Gomberg Collegiate Professor of Engineering.

The first target area to get up and running is the high-repetition target area, which runs experiments with more frequent but lower power laser pulses. Michigan alum Franklin Dollar, an associate professor of physics and astronomy at the University of California Irvine, is the first user, and his team is exploring a new kind of X-ray imaging.

They will use ZEUS to send infrared laser pulses into a gas target of helium, turning it into plasma. That plasma accelerates electrons to high energies, and those electron beams then wiggle to produce very compact X-ray pulses.

New Evidence of Baby Planet in the Making

Artist's illustration of a small Saturn-like planet discovered in the system LkCa 15. The planet resides within dense rings of dust and gas that surround a bright yellow star. Material accumulates in a clump and arc-shape, about 60 degrees away from the planet. Note: This illustration is not to scale.
Credit: M.Weiss/Center for Astrophysics | Harvard & Smithsonian

Astronomers agree that planets are born in protoplanetary disks — rings of dust and gas that surround young, newborn stars. While hundreds of these disks have been spotted throughout the universe, observations of actual planetary birth and formation have proved difficult within these environments.

Now, astronomers at the Center for Astrophysics | Harvard & Smithsonian have developed a new way to detect these elusive newborn planets — and with it, "smoking gun" evidence of a small Neptune or Saturn-like planet lurking in a disk. The results are described today in The Astrophysical Journal Letters.

"Directly detecting young planets is very challenging and has so far only been successful in one or two cases," says Feng Long, a postdoctoral fellow at the Center for Astrophysics who led the new study. "The planets are always too faint for us to see because they’re embedded in thick layers of gas and dust."

Scientists instead must hunt for clues to infer a planet is developing beneath the dust.

Pioneering research using bacteria brings scientists a step closer to creating artificial cells with lifelike functionality

Amoeba-shaped bacteriogenic protocell: membrane (red boundary); nucleus (blue); cytoskeleton (red filaments); vacuole (red circle); ATP production (green). Scale bar, 5 μm.
Credit: Professor Stephen Mann and Dr Can Xu

Scientific Frontline: Extended "At a Glance" Summary: Bacteriogenic Protocells

The Core Concept: Bacteriogenic protocells are advanced synthetic cells constructed by trapping live bacteria within and upon viscous micro-droplets. These structures successfully mimic real-life cellular functionality by utilizing retained bacterial components to produce energy and synthesize proteins.

Key Distinction/Mechanism: While previous attempts to model protocells relied on empty microcapsules with limited capabilities, this approach utilizes a living-material assembly process. By incorporating two types of bacteria into micro-droplets and subsequently destroying them, the process leaves behind thousands of active biological molecules, genetic machinery, and cellular parts integrated directly into the membrane and interior of the synthetic cell.

Major Frameworks/Components: 

• Micro-Droplet Assembly: The foundational step where one population of bacteria is spontaneously captured within viscous droplets while another is trapped at the surface.
• Structural Remodeling: The targeted destruction of the bacteria, which releases components that condense into a single nucleus-like structure, a cytoskeletal-like network of protein filaments, and membrane-bounded water vacuoles.
• Self-Sustainable Energization: The implantation of living bacteria into the protocells to drive self-sustaining ATP production (via glycolysis), ongoing in vitro gene expression, and cytoskeletal assembly.
• Bionic Integration: The resulting cellular bionic system adopts an amoeba-like external morphology driven by on-site bacterial metabolism and growth.

Water can be liquid, gas or ice, right? Think again

Credit: Daniel Sonoca

Scientists at the University of Cambridge have discovered that water in a one-molecule layer acts like neither a liquid nor a solid, and that it becomes highly conductive at high pressures.

Much is known about how ‘bulk water’ behaves: it expands when it freezes, and it has a high boiling point. But when water is compressed to the nanoscale, its properties change dramatically.

By developing a new way to predict this unusual behavior with unprecedented accuracy, the researchers have detected several new phases of water at the molecular level.

Water trapped between membranes or in tiny nanoscale cavities is common – it can be found in everything from membranes in our bodies to geological formations. But this nanoconfined water behaves very differently from the water we drink.

Until now, the challenges of experimentally characterizing the phases of water on the nanoscale have prevented a full understanding of its behavior. But in a paper published in the journal Nature, the Cambridge-led team describe how they have used advances in computational approaches to predict the phase diagram of a one-molecule thick layer of water with unprecedented accuracy.

They used a combination of computational approaches to enable the first-principles level investigation of a single layer of water.

Rensselaer Physics Researcher to Advance Potentially Revolutionary Experiment

 Ethan Brown is an associate professor of physics, applied physics, and astronomy
Credit: Rensselaer Polytechnic Institute

It is believed to be exceedingly rare and slow, but if it actually exists, it would redefine the laws of physics: it’s called neutrinoless double beta decay (NDBD).

Rensselaer Polytechnic Institute’s Ethan Brown, associate professor of physics, applied physics, and astronomy, has received a $285,000 grant from the Department of Energy to contribute to the nEXO experiment to prove that NDBD exists. The nEXO experiment involves the collaboration of dozens of scientists and technologists from institutions around the globe.

Double beta decay is when two neutrons simultaneously decay into two protons and emit two electrons and two electron antineutrinos in the process. With neutrinoless double beta decay, only the electrons and protons are thought to be emitted. This contradicts the accepted laws of physics, in which all particles have a complementary antiparticle.

However, almost 100 years ago, physicist Ettore Majorana hypothesized that this did not necessarily apply to particles without charge, such as the neutrino. His hypothesis is yet to be proven, but it would offer a new understanding of the universe. Since the universe is composed mostly of matter, NBDB would explain why it is not equal parts matter and antimatter.

Vets and pets to reap benefits from new drug to treat common infection

Australia’s 29 million pets look set to benefit from a more effective treatment for Giardia, a common intestinal infection in dogs and cats, thanks to a collaboration between academia and industry.

Pharmaceutical scientists from five Australian universities are partnering with veterinary pharmaceutical company Neoculi Pty Ltd to develop a new drug to treat Giardia, which affects at least 15 per cent of dogs, particularly puppies, and approximately 12 per cent of cats.

Existing treatments on the market are ineffective and have significant drawbacks, according to University of South Australia pharmaceutical scientist Professor Sanjay Garg, one of the key collaborators on the three-year project, led by the University of Newcastle.

Professor Garg says current drugs have limited effectiveness due to parasitic resistance, require multiple treatments and have toxic side effects.

“The drug we are developing is safe and effective in one single dose. We are aiming to produce a palatable formulation that pets will take without any resistance.” Prof Garg says. “It should be available within three years.”

Divorce is more common in albatross couples with shy males

A wandering albatross displaying to potential mates. Both males and females perform elaborate mating dances before bonding with a partner.
Image credit: Samantha Patrick, University of Liverpool

The wandering albatross is the poster bird for avian monogamy. The graceful glider is known to mate for life, partnering up with the same bird to breed, season after season, between long flights at sea.

But on rare occasions, an albatross pair will “divorce” — a term ornithologists use for instances when one partner leaves the pair for another mate while the other partner remains in the flock. Divorce rates vary widely across the avian world, and the divorce rate for wandering albatrosses is relatively low.

Nevertheless, the giant drifters can split up. Scientists at MIT and the Woods Hole Oceanographic Institution (WHOI) have found that, at least for one particular population of wandering albatross, whether a pair will divorce boils down to one important factor: personality.

In a study appearing today in the journal Biology Letters, the team reports that an albatross couple’s chance of divorce is highly influenced by the male partner’s “boldness.” The bolder and more aggressive the male, the more likely the pair is to stay together. The shyer the male, the higher the chance that the pair will divorce.

Are we missing a crucial component of sea-level rise?

Map of Antarctica.
Image credit: Wikimedia Commons

Across Antarctica, some parts of the base of the ice sheet are frozen, while others are thawed. Scientists show that if some currently frozen areas were also to thaw, it could increase ice loss from glaciers that are not currently major sea-level contributors.

Recent efforts using computational modeling to understand how melting ice in Antarctica will impact the planet’s oceans have focused on ice-sheet geometry, fracture, and surface melting – processes that could potentially trigger or accelerate ice-sheet mass loss. Now, researchers have identified an additional process that could have a similarly significant effect on the ice sheet’s future: thawing of the bed, known as basal thaw, at the interface of the land and the miles-thick ice sheet above it.

The new study identifies areas that are not currently losing large amounts of mass but could be poised to match some of the largest contributors to sea-level rise – such as Thwaites Glacier – if they thawed. Antarctica is roughly the size of the United States, and the susceptible regions comprise an area greater than California. The research was published Sept. 14 in Nature Communications.

“You can’t necessarily assume that everywhere that’s currently frozen will stay frozen,” said senior study author Dustin Schroeder, an associate professor of geophysics at the Stanford Doerr School of Sustainability. “These regions may be under-appreciated potential contributors.”

Crime in the realm of bacteria

Christine Kaimer (left) and Susanne Thiery have investigated how soil bacteria fight each other.
Credit: RUB, Marquard

Who would have thought of bacteria: they can sneak up other microorganisms to kill and eat them up.

Bacteria have a variety of survival strategies to provide sufficient food in their densely populated habitats. Certain types of bacteria kill microorganisms of another type, decompose the cells and absorb them as nutrients. How this works is usually unknown. A research team on the biology of microorganisms around Dr. Christine Kaimer examined these processes in more detail. Together with colleagues from the USA, the researchers at the Ruhr University Bochum (RUB) report in the journal Cell Reports on 13. September 2022.

Stop at contact

So far, little is known about the relationship between robbers and prey in the realm of bacteria. However, researchers suspect that bacterial predators can greatly change the composition of a microbiome and thus influence the ecology of their habitat. To learn more about bacterial predator-prey relationships, Christine Kaimer's team examined the predator bacterium Myxococcus xanthus, that often occurs in the ground. It has recently become known that M. xanthus kills his prey cell in direct cell-cell contact: the predator approaches a prey cell, stops when a contact is made, and then causes cell death and decomposition within a few minutes. The researchers examined the molecular mechanisms of this process in more detail.

Decarbonizing the energy system by 2050 could save trillions

Achieving a net zero carbon energy system by around 2050 is possible and profitable
Credit: Appolinary Kalashnikova

Transitioning to a decarbonized energy system by around 2050 is expected to save the world at least $12 trillion, compared to continuing our current levels of fossil fuel use, according to a peer-reviewed study by Oxford University researchers, published in the journal Joule.

The research shows a win-win-win scenario, in which rapidly transitioning to clean energy results in lower energy system costs than a fossil fuel system, while providing more energy to the global economy, and expanding energy access to more people internationally.

The study’s ‘Fast Transition’ scenario, shows a realistic possible future for a fossil-free energy system by around 2050, providing 55% more energy services globally than today, by ramping up solar, wind, batteries, electric vehicles, and clean fuels such as green hydrogen (made from renewable electricity).

Lead author Dr Rupert Way, postdoctoral researcher at the Smith School of Enterprise and the Environment, says, ‘Past models predicting high costs for transitioning to zero carbon energy have deterred companies from investing, and made governments nervous about setting policies that will accelerate the energy transition and cut reliance on fossil fuels. But clean energy costs have fallen sharply over the last decade, much faster than those models expected.

‘Our latest research shows scaling-up key green technologies will continue to drive their costs down, and the faster we go, the more we will save. Accelerating the transition to renewable energy is now the best bet, not just for the planet, but for energy costs too.’

How the brain focuses on what’s in mind

Remembering directions someone just gave you is an example of working memory. In a new study, MIT researchers show that the brain's focus on the contents of what its holding in mind derives from bursts of gamma frequency rhythms in the front of the brain.
Photo credit: George Pak

Working memory, that handy ability to consciously hold and manipulate new information in mind, takes work. In particular, participating neurons in the prefrontal cortex have to work together in synchrony to focus our thoughts, whether we’re remembering a set of directions or tonight’s menu specials. A new study by researchers based at The Picower Institute for Learning and Memory at MIT shows how that focus emerges.

The key measure in the study in Scientific Reports is the variability of the neurons’ activity. Scientists widely agree that less variability activity means more-focused attunement to the task. Measures of that variability have indeed shown that it decreases when humans and animals focus during working memory games in the lab.

In several studies between 2016 and 2018, lead author Mikael Lundqvist and co-senior author Earl K. Miller showed through direct measurements of hundreds of neurons and rigorous modeling that bursts of gamma frequency rhythms in the prefrontal cortex coordinate neural representation of the information held in mind. The information representation can be measured in the synchronized spiking of populations of individual neurons. Bursts of beta frequency rhythms, meanwhile, implement the brain’s manipulation of that information. The theory, which Miller dubbed “Working Memory 2.0” challenged a long-held orthodoxy that neurons maintain working memory information through steady, persistent activity. Proponents of that older model, which emerged from averaged measurements made in relatively few neurons, used computer-based modeling of brain activity to argue that reduced variability cannot emerge from intermittent bursts of rhythmic activity.