New study shows why some minds can’t switch off at night

Photo Credit: Cottonbro Studio

Australian researchers have found compelling evidence that insomnia may be linked to disruptions in the brain’s natural 24-hour rhythm of mental activity, shedding light on why some people struggle to ‘switch off’ at night. 

Published in Sleep Medicine, the study led by the University of South Australia (UniSA) is the first to map how cognitive activity fluctuates across the day in individuals with chronic insomnia, compared to healthy sleepers. 

Insomnia affects about 10% of the population, and up to 33% of older adults, with many reporting an overactive or ‘racing’ mind at night. 

While this has long been linked to cognitive hyperarousal, it has remained unclear where these thought patterns stem from. 

After nearly 100 years, scientists may have detected dark matter

Gamma-ray image of the Milky Way halo (with details).
Gamma-ray intensity map excluding components other than the halo, spanning approximately 100 degrees in the direction of the Galactic center. The horizontal gray bar in the central region corresponds to the Galactic plane area, which was excluded from the analysis to avoid strong astrophysical radiation.
 Image Credit: ©2025 Tomonori Totani, The University of Tokyo

In the early 1930s, Swiss astronomer Fritz Zwicky observed galaxies in space moving faster than their mass should allow, prompting him to infer the presence of some invisible scaffolding — dark matter — holding the galaxies together. Nearly 100 years later, NASA’s Fermi Gamma-ray Space Telescope may have provided direct evidence of dark matter, allowing the invisible matter to be “seen” for the very first time.

Dark matter has remained largely a mystery since it was proposed so many years ago. Up to this point, scientists have only been able to indirectly observe dark matter through its effects on observable matter, such as its ability to generate enough gravitational force to hold galaxies together. The reason dark matter can’t be observed directly is because the particles that make up dark matter don’t interact with electromagnetic force — meaning dark matter doesn’t absorb, reflect or emit light.

Immunology: In-Depth Description

Image Credit: Scientific Frontline / AI generated

Immunology is the branch of biomedical science concerned with the structure, function, and disorders of the immune system—the complex network of cells, tissues, and organs that protect an organism from foreign invaders. Its primary goal is to understand how biological systems identify and eliminate pathogens (such as bacteria, viruses, fungi, and parasites) while maintaining tolerance for the body's own healthy tissue (distinguishing "self" from "non-self").

Flowering discovery could lead to more reliable mungbean yields

Mungbean flowers at UQ Gatton.
Photo Credit: Megan Pope

New breeding opportunities for an important cash crop have been unlocked by University of Queensland and Grains Research and Development Corporation (GRDC)-supported research. 

Queensland Alliance of Agriculture and Food Innovation PhD candidate Caitlin Dudley, supported by a GRDC Research Scholarship, has revealed key insights about mungbean flowering through extensive field trials. 

“Our research found that when mungbean flowers, and how long they flowers, are independent traits with distinct genetic controls,” Ms Dudley said. 

“That’s important to know because it opens opportunities for breeders to optimize flowering time to improve yield for specific growing environments. 

Laparoscopic surgery significantly reduces blood loss and improves jaundice recovery for severe newborn liver disease

Pediatric surgery ward at Nagoya University Hospital, where laparoscopic surgery for biliary atresia is performed.
Photo Credit: Merle Naidoo, Nagoya University

Biliary atresia affects newborns when bile ducts become blocked, leading to liver damage that often requires transplants—a new study evaluates an alternative to traditional open surgery.

Nagoya University researchers and their collaborators have found that minimally invasive laparoscopic surgery significantly reduces blood loss and improves jaundice recovery compared to traditional open surgery for treating biliary atresia—a serious liver condition in newborns. The study, published in Hepatobiliary Surgery and Nutrition, also found that high-dose steroid therapy after surgery does not necessarily improve outcomes for treating this condition.

Biliary atresia affects 1 in 15,000 newborns and is the leading cause of liver transplants in children. It occurs when bile ducts become blocked or do not develop properly, which prevents effective liver function and leads to progressive damage. What causes this blockage is unknown, and surgery is usually performed within the first two to three months of birth when the condition is diagnosed. 

New observations suggest Mars’ south pole lacks lake beneath the ice

An artist's concept of NASA’s Mars Reconnaissance Orbiter, which has been orbiting the Red Planet since 2006. The antenna is part of SHARAD, a radar that peers below the Martian surface.
Image Credit: NASA/JPL-Caltech

A new study published in Geophysical Research Letters casts doubt on a 2018 discovery of a briny lake potentially lurking beneath Mars’ south polar cap.

SHARAD, the Shallow Radar sounder on NASA’s Mars Reconnaissance Orbiter (MRO), performed a maneuver that allowed it to peer deeper beneath the polar ice than ever before. It recorded only a faint signal where MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding), the low-frequency radar on the European Space Agency’s Mars Express spacecraft, found a highly radar-reflective surface under the ice in 2018, which that team interpreted to be due to the presence of liquid water.

“The existence of liquid water under the south pole is really compelling and exciting, but if it is there, SHARAD should also see a very bright reflectance spot, and we don’t,” said study lead author Gareth Morgan, a SHARAD co-investigator and Planetary Science Institute senior scientist.

Scientific Models Overestimate Natural Processes That Mitigate Climate Change

Silky lupine plants at Lassen National Park in California
Photo Credit: Duncan Menge

High levels of atmospheric carbon dioxide intensify climate change, but high carbon dioxide levels can also stimulate plant growth. Plant growth removes carbon dioxide from the atmosphere, partially mitigating the effects of climate change. However, plants only grow faster in the presence of high levels of carbon dioxide if they can also acquire enough nitrogen from the atmosphere to do so. The actual amount of nitrogen acquired from the atmosphere was reassessed in a study co-led by Columbia faculty that was released this summer; it was shown to be significantly lower than previously estimated.

Concordia researchers identify key marker linking coronary artery disease to cognitive decline

Zacharie Potvin-Jutras, with Claudine Gauthier:
“Our goal is to examine conditions at the onset of a heart disease, before there has been any significant impact on the brain”
Photo Credit: Courtesy of Concordia University

Individuals with coronary artery disease (CAD) — a constricting or blocking of blood vessels feeding the heart — face increased risks of strokes, cognitive impairment and dementia. However, the link between CAD and cognitive function is not fully understood. 

A new study led by Concordia researchers looks at how the disease affects the brain’s white matter, the network of nerve fibers that connects different regions of the brains and is critical to transmitting information efficiently. 

The study, published in the Journal of Neuroscience, applied a novel multivariate approach using 12 separate metrics. The researchers compared test results and MRI scans of 43 patients with CAD to those of 36 healthy individuals. All participants were over the age of 50. 

Microplastics pose a human health risk in more ways than one

Bio-beads collected near Truro.
Photo Credit Beach Guardian

A new study shows that microplastics in the natural environment are colonized by pathogenic and antimicrobial resistant bacteria. The study team calls for urgent action for waste management and strongly recommends wearing gloves when taking part in beach cleans. 

Microplastics are plastic particles less than 5mm in size and are extremely widespread pollutants. It is estimated that over 125 trillion particles have accumulated in the ocean (surface to seabed) and they have also been detected in soils, rivers, lakes, animals and the human body. 

An emerging concern associated with microplastics is the microbial communities that rapidly make their home on the particle surface, forming complex biofilms known as the “Plastisphere”. These communities may often include pathogenic (disease-causing) or antimicrobial resistant (AMR) bacteria. 

The seamounts of Cape Verde: a biodiversity hotspot and a priority for marine conservation in the central-eastern Atlantic

Image Credit: Projecte Luso/iMirabilis2/iAtlantic

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Scientists have identified sandy seafloors as a significant and previously overlooked source of methane, a potent greenhouse gas, challenging the long-held assumption that these oxygen-rich environments were biologically inactive regarding methanogenesis.
• Methodology: Researchers conducted extensive fieldwork in coastal zones of Denmark and Australia, utilizing biogeochemical sensors to monitor oxygen fluctuations and genetic sequencing to identify methanogenic archaea within permeable sandy sediments.
• Key Data: Atmospheric methane concentrations have surged by 150% since the mid-1700s, and the study reveals that even "clean" sand can host vibrant microbial communities that activate methane production within hours once oxygen levels drop during calm sea conditions.
• Significance: The discovery identifies a "hidden" feedback loop where coastal warming and increased organic runoff from dying seagrasses can trigger rapid methane release, potentially accelerating global climate change beyond current predictive models.
• Future Application: These findings necessitate the integration of coastal sandy shelf data into global carbon budget assessments and provide a new framework for managing marine protected areas to mitigate methane "hotspots" caused by sediment stagnation.
• Branch of Science: Biogeochemistry and Marine Ecology.
• Additional Detail: The study found that methanogenic microbes in sand exhibit a unique "flexible lifestyle," remaining dormant in oxygenated water but feasting on the metabolites of marine plants as soon as local conditions turn anaerobic.

Ecological winners: Why some species dominate the planet

A new study sheds light on why some species seem to thrive nearly everywhere, while others are rare and have very limited ranges. Pictured is the boojum tree (Fouquieria columnaris), native only to a few desert regions in Mexico's Gulf of California. 
Photo Credit: Daniel Stolte

Few ideas in science have been tested and confirmed as thoroughly as evolution by natural selection. 160 years ago, Charles Darwin proposed the theory of evolution by natural selection after observing organisms that had developed highly specialized traits to better survive or reproduce in their environments. Whether the same process can explain global patterns of biodiversity, however – why most species are restricted to certain environments while a few outliers seem to be found everywhere – remains largely uncertain.

"We still are not exactly sure why most species are confined to narrow ranges, while only a few thrive nearly everywhere," said Brian Enquist, professor in the University of Arizona Department of Ecology and Evolutionary Biology and senior author of a new study providing the strongest global evidence yet that abundant plant species became so dispersed over time because of their ability to tolerate diverse climates.

Looping long-necked dinosaur site reveals its secrets

An aerial view of the loop section of the West Gold Hill Dinosaur Tracksite in Colorado.
Photo Credit: Dr. Paul Murphey

An analysis of a unique looping trail of ancient footprints in the United States reveals the dinosaur which made it may have been limping. 

The site near Ouray in Colorado is one of the most continuous and tightly turning sauropod trackways ever documented. 

Dr. Anthony Romilio from The University of Queensland’s Dinosaur Lab analyzed more than 130 footprints along the 95.5-metre track made 150 million years ago. 

“This was left in the Late Jurassic when long-necked dinosaurs such as Diplodocus and Camarasaurus roamed North America,” Dr Romilio said. 

The Gut Brain’s Role in Allergy Regulation

This tissue section, taken from the intestine of a mouse unable to produce the neuropeptide VIP, clearly shows the striking frequency with which certain cell types occur on the intestine's surface. These include villous cells (red), mucus-producing goblet cells (yellow), Paneth cells (pink) and stem cells (green).
Image Credit: © Charité | Luisa Barleben

Scientific Frontline: Extended "At a Glance" Summary: The Intestinal Nervous System ("Gut Brain") and Allergy Regulation

The Core Concept: The intestinal nervous system (the "gut brain") acts as a critical conductor of the intestinal barrier by regulating the development of intestinal epithelial cells to modulate immune responses. Disruptions in this neural control can lead to intestinal inflammation and the development of allergic reactions.

Key Distinction/Mechanism: Unlike its role in digestion, the intestinal nervous system uses the neuropeptide VIP (vasoactive intestinal peptide) to communicate directly with intestinal stem cells. This signaling prevents the over-proliferation and abnormal differentiation of tuft cells, which are responsible for triggering allergy-like immune responses when they occur in excess.

Major Frameworks/Components:

• Intestinal Nervous System (ENS): Acts as the primary regulator between stem cells and immune cells.
• Vasoactive Intestinal Peptide (VIP): The specific messenger molecule used by nerve cells to control stem cell development.
• Intestinal Stem Cells (LGR5+): Regulated by VIP signaling to ensure proper lineage differentiation.
• Tuft Cells: Secretory cells that, when unregulated, release signals promoting type 2 immune (allergic) responses.
• Intestinal Barrier: The mucosal layer that maintains gut health through a balance of nerve, immune, and microbiome interactions.

Ichthyology: In-Depth Description

Image Credit: Scientific Frontline / AI generated

Ichthyology is the specialized branch of zoology devoted to the scientific study of fish, encompassing all three major groups: jawless fish (Agnatha), cartilaginous fish (Chondrichthyes), and bony fish (Osteichthyes). This discipline investigates the biology, morphology, taxonomy, evolution, and behavioral patterns of the most diverse group of vertebrates on Earth, ranging from microscopic species to massive biological entities like whale sharks.

Stroke scientists gather more evidence for presence of ‘gut-brain axis’

Image Credit: Scientific Frontline / stock image

Research on mice by scientists at The University of Manchester has shed new light on why the guts’ immune system changes after a stroke and how it might contribute to gastro-intestinal problems. 

Published in Brain, Behavior and Immunity, the study adds to the emerging idea of the “gut-brain axis” – in which scientists suggest allows communication between the two organs in both health and disease. 

The study casts more light on the biology of stroke, a life-threatening medical emergency that disrupts blood flow to parts of the brain often causing long-term effects to mobility and cognition. 

Stroke patients are also at risk of secondary bacterial infections and often exhibit gastrointestinal symptoms including difficulty swallowing and constipation.