Stress increases Alzheimer’s risk in female mice but not males

Stress causes the levels of Alzheimer's proteins to rise in females' brains but not males' brains, according to a new study in mice by researchers at Washington University School of Medicine in St. Louis. This difference may contribute to women's greater risk of developing Alzheimer's disease.
Photo Credit: Karolina Grabowska

Women are about twice as likely as men to be diagnosed with Alzheimer’s disease. Some of that is age; in the U.S., women outlive men by five to six years, and advanced age is the strongest risk factor for Alzheimer’s. But there’s more to it than that, so Alzheimer’s researchers continue to look for other reasons why women have an elevated risk of the deadly neurodegenerative disease.

Stress may be one such reason. A study by researchers at Washington University School of Medicine in St. Louis shows that the effect stress has on the brain differs by sex, at least in mice. In stressful situations, levels of the Alzheimer’s protein amyloid beta rises sharply in the brains of females but not males. In addition, the researchers identified a molecular pathway that is active in brain cells from female mice but not male mice, and showed that it accounts for the divergent responses to stress.

The findings, published May 2 in Brain, add to a growing collection of evidence that sex matters in health and disease. From cancer to heart disease to arthritis, scientists have found differences between males and females that could potentially affect how men and women respond to efforts to prevent or treat chronic diseases.

Exercise Increases the Number of Cancer-Destroying Immune Cells in Cancer Patients

Two new Finnish studies show that short bouts of light or moderate exercise can increase the number of immune cells in the bloodstream of cancer patients.
Photo Credit: Zen Chung

Exercise decreases the risk of cancer and reduces side effects of cancer treatments. In addition, it improves patients’ quality of life and the prognosis of cancer patients.

 “It was previously thought that cancer patients should just rest after a cancer diagnosis. Today, we have more and more researched information that exercise can even improve the prognosis of cancer. However, it is not yet fully known how exercise controls cancer,” explains Research Assistant Tiia Koivula.

Previous preclinical studies have found that exercise affects the functioning of the immune system so that more immune cells are transferred to the tumor site and they become more active in destroying cancer cells. Two studies conducted at the Turku PET Centre of the University of Turku in Finland aimed to find out whether a short exercise bout affects the mobilization of immune cells in cancer patients.

Quantum Entanglement of Photons Doubles Microscope Resolution

Using a "spooky" phenomenon of quantum physics, Caltech researchers have discovered a way to double the resolution of light microscopes.
Photo Credit: Lance Hayashida/Caltech

In a paper appearing in the journal Nature Communications, a team led by Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering, shows the achievement of a leap forward in microscopy through what is known as quantum entanglement. Quantum entanglement is a phenomenon in which two particles are linked such that the state of one particle is tied to the state of the other particle regardless of whether the particles are anywhere near each other. Albert Einstein famously referred to quantum entanglement as "spooky action at a distance" because it could not be explained by his relativity theory.

According to quantum theory, any type of particle can be entangled. In the case of Wang's new microscopy technique, dubbed quantum microscopy by coincidence (QMC), the entangled particles are photons. Collectively, two entangled photons are known as a biphoton, and, importantly for Wang's microscopy, they behave in some ways as a single particle that has double the momentum of a single photon.

Since quantum mechanics says that all particles are also waves, and that the wavelength of a wave is inversely related to the momentum of the particle, particles with larger momenta have smaller wavelengths. So, because a biphoton has double the momentum of a photon, its wavelength is half that of the individual photons.

Let’s get cracking: Sandia scientists detect gases from fractured rock

Steve Bauer, a retired Sandia National Laboratories geoscientist, is preparing his sensitive mass spectrometer to detect the gases released by crushing a piece of granite. Recently he detected noble gases released by a test explosion underground. Someday this research might improve the prediction of earthquakes or detection of underground explosions.
Photo Credit: Craig Fritz

Geoscientists have detected specific gases being released from fractured rocks in real time after a series of small chemical explosions set underground.

This fundamental research, led by Sandia National Laboratories geoscientist Steve Bauer, could one day improve the prediction of earthquakes or detection of underground explosions.

“In the different shots, we were able to measure different relative amounts of noble gases, which we hope is consistent with the amount of deformation caused by the explosion,” said Bauer, who recently retired. “The chemical explosions had the same amount of TNT equivalent, but produced different amounts of liquids and gases, so they deformed the rock to different extents. My pie-in-the-sky goal is to measure the amount of noble gas at a location after an explosion or earthquake and then be able to understand the amount of strain the rock has experienced.”

Fossil find in California shakes up the natural history of cycad plants

Three-dimensional reconstruction of the whole cone and different views of the same cone scale. Scale bar: cone = 400 microns; cone scales = 200 microns.
Image Credit: Andres Elgorriaga, Brian Atkinson

Cycads, a group of gymnosperms which can resemble miniature palm trees (like the popular sago palm houseplant) were long thought to be “living fossils,” a group that had evolved minimally since the time of the dinosaurs. Now, a well-preserved 80-million-year-old pollen cone discovered in California has rewritten scientific understanding of the plants.

The findings are detailed in a paper by two University of Kansas paleobotanists just published in the journal New Phytologist.

“Cycads aren’t well-known but make up a significant part of plant diversity, accounting for around 25% of all gymnosperms,” said lead author Andres Elgorriaga, postdoctoral researcher with the KU Department of Ecology & Evolutionary Biology and KU Biodiversity Institute and Natural History Museum3. “Cycads are plants that have thick stems and short stature, with thick, palm-like leaves on top. They produce cones like pine cones and are related to other seed-bearing plants that also don’t produce flowers, like Ginkgo and the monkey puzzle tree. But they’re also highly endangered, with the highest level of endangerment among all plant groups. Trafficking of cycads also is a significant issue.”

Essential mechanism for bacterial gut colonization discovered

Tomogram of a Bacteroides thetaiotaomicron cell.
Image Credit: Matthew Swulius / Pennsylvania State University
(CC BY-NC-ND 4.0)

New light has been shed on a key event that contributes to the successful colonization of bacteria in the gut of mice, according to a new study from Yale University and Penn State. The study, published in Science, reveals that a physical process called "liquid-liquid phase separation" is essential for the survival and colonization of the beneficial bacteria Bacteroides thetaiotaomicron in the gut.

“In our field we are trying to understand how bacteria can colonize your gut and what the molecular components are that allow these organisms to reside in your intestines, because not all bacteria can,” said Guy Townsend, assistant professor of biochemistry and molecular biology at the Penn State College of Medicine and an author on the paper. Prior to this work, researchers did not understand the mechanisms that allowed B. thetaiotaomicron to thrive in the gut of mammals.

The researchers demonstrated the crucial role played by an “intrinsically disordered domain” (IDR) within a particular protein in the bacterium, called Rho, that facilitates liquid-liquid phase separation.

Liquid-liquid phase separation is when two liquids that don't mix well separate into different parts because of their chemical differences. This process helps cells create structures that don't have a membrane and are important for many cell functions.

The inequalities of low-carbon electricity

UNIGE researchers evaluated the consequences of 248 decarbonization scenarios on 296 European regions.
Photo Credit: Rob Martin

Greenhouse gas reduction, new jobs, new investment opportunities: the benefits of decarbonizing the electricity sector - one of the most polluting - are obvious. However, a transition to lower-carbon electricity production could have a negative impact on some regions, depending on their vulnerabilities and their capacity to adapt, while it could have a positive impact on others. A team from the University of Geneva (UNIGE) has precisely mapped the socio-economic consequences of electricity decarbonization for 296 regions in Europe by 2050. It shows that the southern and south-eastern regions of the continent could be the most vulnerable. These results can be found in Nature Communications.

The electricity consumed in Europe is largely produced by highly polluting fossil fuel power plants (coal, gas). This sector alone is responsible for a quarter of the continent’s greenhouse gas (GHG) emissions. Decarbonizing electricity has therefore become a priority. It is also a prerequisite for the decarbonization of other sectors that need to be electrified, such as heating and transport.

The benefits of such a transition are obvious (reduced air pollution, new employment opportunities). However, the process could also maintain or lead to some new inequalities between regions. For example, an area with a coal-fired power plant will lose many jobs and tax revenues if the plant closes. It will be doubly penalized if there is little land available to build new renewable energy plants.

Beyond Moore’s Law: Innovations in solid-state physics include ultra-thin ‘two-dimensional’ materials and more

From left to right: Kaustav Banerjee and Arnab Pal
Photo Credit: Lilli McKinney

In the ceaseless pursuit of energy-efficient computing, new devices designed at UC Santa Barbara show promise for enhancements in information processing and data storage.

Researchers in the lab of Kaustav Banerjee, a professor of electrical and computer engineering, have published a new paper describing several of these devices, “Quantum-engineered devices based on 2D materials for next-generation information processing and storage,” in the journal Advanced Materials. Arnab Pal, who recently received his doctorate, is the lead author.

Each device is intended to address challenges associated with conventional computing in a new way. All four operate at very low voltages and are characterized as being low leakage, as opposed to the conventional metal-oxide semiconductor field-effect transistors (MOSFETs) found in smartphones that drain power even when turned off. But because they are based on processing steps similar to those used to make MOSFETs, the new devices could be produced at scale using existing industry-standard manufacturing processes for semiconductors.

The most promising of the two information-processing devices, according to Banerjee, is the spin-based field-effect transistor, or spin-FET, which takes advantage of the magnetic moment — or spin — of the electrons that power the device. In this case, the materials belong to the transition metal dichalcogenide group of compounds, which are based on transition metals. 

Why mosses are vital for the health of our soil and Earth

When mosses cover the soil, it's a good sign, not a bad one. They lay foundations for other plant life to thrive.
Photo Credit: University of New South Wales

Often ignored or even removed, moss provides stabilization for plant ecosystems the world over.

Some people see moss growing in their gardens as a problem, but what they may not realize is this ancient ancestor of all plants is bringing lots of benefits to our green spaces, such as protecting against erosion.

Now a massive global study led by UNSW Sydney has found mosses are not just good for the garden, but are just as vital for the health of the entire planet when they grow on topsoil. Not only do they lay the foundations for plants to flourish in ecosystems around the world, they may play an important role mitigating against climate change by capturing vast amounts of carbon.

In a study published today in the journal Nature Geoscience, lead author Dr David Eldridge and more than 50 colleagues from international research institutions described how they collected samples of mosses growing on soil from more than 123 ecosystems across the globe, ranging from lush, tropical rainforest, to barren polar landscapes, through to arid deserts like those found in Australia. The researchers found that mosses cover a staggering 9.4 million km2 in the environments surveyed, which compares in size to Canada or China.

‘Raw’ data show AI signals mirror how the brain listens and learns

Researchers found strikingly similar signals between the brain and artificial neural networks. The blue line is brain wave when humans listen to a vowel. Red is the artificial neural network’s response to the exact same vowel. The two signals are raw, meaning no transformations were needed.
Illustration Credit: Courtesy Gasper Begus

New research from the University of California, Berkeley, shows that artificial intelligence (AI) systems can process signals in a way that is remarkably similar to how the brain interprets speech, a finding scientists say might help explain the black box of how AI systems operate.

Using a system of electrodes placed on participants’ heads, scientists with the Berkeley Speech and Computation Lab measured brain waves as participants listened to a single syllable — “bah.” They then compared that brain activity to the signals produced by an AI system trained to learn English.

“The shapes are remarkably similar,” said Gasper Begus, assistant professor of linguistics at UC Berkeley and lead author on the study published recently in the journal Scientific Reports. “That tells you similar things get encoded, that processing is similar. “

A side-by-side comparison graph of the two signals shows that similarity strikingly.