Pumas are back in Patagonia and Penguins are paying the price

 Should conservation efforts focus on protecting one iconic species if that protection may harm another, especially in landscapes still recovering from human activity? This question lies at the center of a growing conservation challenge at Monte Leon National Park on Argentina's Patagonian coast.

The situation highlights the complexity of restoring ecosystems that were altered for decades and are now undergoing rapid change.

Pumas Return and Penguins Face a New Threat

After cattle ranching ended in southern Argentina in 1990, pumas (Puma concolor) gradually began reclaiming parts of their historic range. Their return brought them into contact with Magellanic penguins (Spheniscus magellanicus) for the first time in modern history.

The penguins had previously moved from offshore islands to the mainland, taking advantage of the absence of land predators. With few defenses against large carnivores, they became easy prey once pumas arrived. Until recently, however, scientists did not know how much this new interaction was affecting penguin population numbers.

Long Term Monitoring in Monte Leon National Park

Since the park was established in 2004, penguin colonies have been closely observed by researchers from the Centro de Investigaciones de Puerto Deseado of the Universidad Nacional de la Patagonia Austral, working alongside rangers from Monte Leon National Park. Over a four year period (2007-2010), they recorded penguin carcasses linked to puma attacks.

For the latest study, the team partnered with researchers from Oxford University's Wildlife Conservation Research Unit (WildCRU) to analyze the data and assess the long term implications for the colony.

Thousands of Penguins Killed

Using carcass counts, the researchers estimated that more than 7,000 adult penguins were killed during the four year study period. Many of the birds were only partially eaten or not eaten at all, indicating that the killings were not solely for food. This figure represents about 7.6% of the adult population (around 93,000 individuals).

Lead author Melisa Lera, a postgraduate student at WildCRU, Oxford University said: "The number of carcasses showing signs of predation we found in the colony is overwhelming, and the fact that they were left uneaten means pumas were killing more penguins than they required for food. This is consistent with what ecologists describe as 'surplus killing'. It is comparable to what is seen in domestic cats when prey are abundant and/or vulnerable: ease of capture can lead to cats hunting more birds, even when they do not end up actually eating them. We needed to understand if the penguin colony's persistence could be threatened due to this behavior."

Source: ScienceDaily

Physicists solve a quantum mystery that stumped scientists for decades

 Physicists have developed a new theory that brings together two major areas of modern quantum physics. The work explains how a single unusual particle behaves inside a crowded quantum environment known as a many-body system. In this setting, the particle can act either as something that moves freely or as something that remains nearly fixed within a vast collection of fermions, often called a Fermi sea. Researchers at the Institute for Theoretical Physics at Heidelberg University created this framework to explain how quasiparticles form and to link two quantum states that were previously thought to be incompatible. They say the results could strongly influence ongoing experiments in quantum matter.

In quantum many-body physics, scientists have long debated how impurities behave when surrounded by large numbers of other particles. These impurities can be unusual electrons or atoms (i.e., exotic electrons or atoms). One widely used explanation is the quasiparticle model. In this picture, a single particle moves through a sea of fermions such as electrons, protons, or neutrons and constantly interacts with those around it. As it travels, it pulls nearby particles along with it, creating a combined entity called a Fermi polaron. Although it behaves like a single particle, this quasiparticle arises from the shared motion of the impurity and its surroundings. As Eugen Dizer, a doctoral candidate at Heidelberg University, notes, this idea has become central to understanding strongly interacting systems ranging from ultracold gases to solid materials and nuclear matter.When Heavy Particles Disrupt the System

A very different scenario appears in a phenomenon known as Anderson's orthogonality catastrophe. This occurs when an impurity is so heavy that it barely moves at all. Its presence dramatically alters the surrounding system. The wave functions of the fermions change so extensively that they lose their original form, creating a complicated background where coordinated motion breaks down. Under these conditions, quasiparticles cannot form. Until now, physicists have not had a clear theory that links this extreme case with the mobile impurity picture. By applying a range of analytical tools, the Heidelberg team has managed to connect these two descriptions within a single framework.

Small Motions With Big Consequences

"The theoretical framework we developed explains how quasiparticles emerge in systems with an extremely heavy impurity, connecting two paradigms that have long been treated separately," explains Eugen Dizer, who works in the Quantum Matter Theory group led by Prof. Dr Richard Schmidt. A key insight behind the theory is that even very heavy impurities are not perfectly still. As their surroundings adjust, these particles undergo tiny movements. Those slight shifts create an energy gap that makes it possible for quasiparticles to form, even in a strongly correlated environment. The researchers also showed that this process naturally accounts for the transition from polaronic states to molecular quantum states.

Implications for Quantum Experiments

Prof. Schmidt says the new results offer a flexible way to describe impurities that can be applied across different dimensions and interaction types. "Our research not only advances the theoretical understanding of quantum impurities but is also directly relevant for ongoing experiments with ultracold atomic gases, two-dimensional materials, and novel semiconductors," he adds.

Source: ScienceDaily

New drug resets the body clock and cuts jet lag recovery nearly in half

 A research team led by scientists from several Japanese institutions has identified a compound called Mic-628 that directly influences the body's internal timing system. The group included Emeritus Professor Tei H. (Kanazawa University), Associate Professor Takahata Y. (Osaka University), Professor Numano R. (Toyohashi University of Technology), and Associate Professor Uriu K. (Institute of Science Tokyo). Their experiments showed that Mic-628 specifically activates Per1, a core gene that helps regulate daily biological rhythms in mammals.

The researchers found that Mic-628 works by attaching to CRY1, a protein that normally suppresses clock gene activity. This interaction encourages the formation of a larger molecular complex known as CLOCK-BMAL1-CRY1-Mic-628. Once formed, this complex switches on Per1 by acting at a specific DNA site called a "dual E-box." Through this mechanism, Mic-628 shifts the timing of both the brain's master clock located in the suprachiasmatic nucleus (SCN) and clocks in other organs, including the lungs. Notably, these clock shifts occurred together and did not depend on when the compound was given.Faster Recovery From Jet Lag in Animal Tests

To test real-world relevance, the team used a mouse model designed to mimic jet lag by advancing the light-dark cycle by six hours (6-hour light-dark phase advance). Mice that received a single oral dose of Mic-628 adjusted to the new schedule much faster, taking four days instead of seven. Further mathematical analysis showed that this steady, one-direction shift forward is driven by a built-in feedback loop involving the PER1 protein, which helps stabilize the clock change.

Why Advancing the Clock Is So Difficult

Adjusting to earlier schedules, such as traveling east across time zones or working night shifts, requires the body clock to move forward. This type of adjustment is typically slower and more stressful for the body than delaying the clock. Common approaches like light exposure or melatonin depend heavily on precise timing and often produce uneven results. Because Mic-628 consistently advances the clock regardless of dosing time, it offers a fundamentally different drug-based approach to circadian reset.

What Comes Next for Mic-628

The researchers plan to continue studying Mic-628 to better understand its safety and effectiveness in additional animal studies and in humans. Since the compound reliably moves the body clock forward through a clearly defined biological pathway, it could become a model "smart drug" for addressing jet lag, sleep problems linked to shift work, and other disorders caused by circadian misalignment.

Source: ScienceDaily

A hidden Aloe vera compound takes aim at Alzheimer’s

 Scientists are continuing to search for new ways to treat Alzheimer's disease (AD), a progressive brain disorder that affects memory, thinking, and behavior. In a recent study, researchers identified several compounds found in Aloe vera that could offer new possibilities for future treatments. Aloe vera is best known as a soothing plant used for skin care, but it also contains natural chemicals that may influence biological processes inside the body.

The study, published in Current Pharmaceutical Analysis, focused on how these plant compounds interact with key enzymes involved in Alzheimer's disease. Using computer-based research methods, scientists examined whether Aloe vera compounds could interfere with processes linked to the breakdown of brain signaling in people with AD.Key Enzymes Linked to Memory Loss

The research centered on two enzymes called acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). These enzymes play an important role in breaking down acetylcholine, a chemical messenger that helps nerve cells communicate. In Alzheimer's disease, acetylcholine levels are already reduced, which contributes to memory loss and cognitive decline. Medications that slow down these enzymes can help preserve acetylcholine and improve symptoms in some patients.

To study this process, researchers used in silico methods, which rely on computer simulations rather than laboratory experiments. These methods allow scientists to predict how molecules might behave inside the body before moving on to real world testing. "Our findings suggest that Beta sitosterol, one of the Aloe vera compounds, exhibits significant binding affinities and stability, making it a promising candidate for further drug development," said Meriem Khedraoui, the lead author of the study.

How Computer Models Test Drug Potential

The team used molecular docking and molecular dynamics simulations to see how different Aloe vera compounds attach to AChE and BChE. Molecular docking helps predict how well a compound fits into an enzyme, while molecular dynamics simulations examine how stable that interaction remains over time.

Among all the compounds tested, Beta sitosterol stood out. It showed binding affinities of −8.6 kcal/mol with AChE and −8.7 kcal/mol with BChE, meaning it attached more strongly to both enzymes than other compounds tested, including Succinic acid. Strong binding suggests the compound may be effective at slowing enzyme activity. "These results highlight the potential of Beta sitosterol as a dual inhibitor, which could be crucial in managing Alzheimer's disease," said Khedraoui.

Evaluating Safety and Drug Behavior in the Body

In addition to enzyme binding, the researchers also examined whether the compounds might be safe and effective if used as medications. This was done using ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) analysis. ADMET testing helps predict how a compound enters the body, how it spreads through tissues, how it is broken down, how it is removed, and whether it could cause harmful side effects.

Source: ScienceDaily

Scientists finally solve a 100-year-old mystery in the air we breathe

 Researchers at the University of Warwick have developed a new method that makes it possible to predict how irregularly shaped nanoparticles move through the air. These particles are a major category of air pollution and have long been difficult to model accurately. The new approach is the first that is both simple and predictive, allowing scientists to calculate particle motion without relying on overly complex assumptions.

Each day, people inhale millions of microscopic particles, including soot, dust, pollen, microplastics, viruses, and engineered nanoparticles. Some of these particles are so small that they can penetrate deep into the lungs and even enter the bloodstream. Exposure has been linked to serious health problems, including heart disease, stroke, and cancer.Most airborne particles do not have smooth or symmetrical shapes. However, traditional mathematical models usually assume these particles are perfect spheres because spherical shapes make equations easier to solve. This simplification limits scientists' ability to accurately track how real-world particles behave, especially those with irregular shapes that may pose greater health risks.

Reviving a Century-Old Equation for Modern Science

A researcher at the University of Warwick has now introduced the first straightforward method that can predict how particles of virtually any shape move through air. The study, published in Journal of Fluid Mechanics Rapids, updates a formula that is more than 100 years old and addresses a major gap in aerosol science.

The paper's author, Professor Duncan Lockerby, School of Engineering, University of Warwick said: "The motivation was simple: if we can accurately predict how particles of any shape move, we can significantly improve models for air pollution, disease transmission, and even atmospheric chemistry. This new approach builds on a very old model -- one that is simple but powerful -- making it applicable to complex and irregular-shaped particles."

Correcting a Key Oversight in Aerosol Physics

The breakthrough came from taking a fresh look at one of the foundational tools in aerosol science, known as the Cunningham correction factor. First introduced in 1910, the correction factor was designed to explain how drag forces on tiny particles differ from classical fluid behavior.

In the 1920s, Nobel Prize winner Robert Millikan refined the formula. During that process, a simpler and more general correction was overlooked. Because of this, later versions of the equation remained restricted to particles that were perfectly spherical, limiting their usefulness for real-world conditions.

Professor Lockerby's work restructures Cunningham's original idea into a broader and more flexible form. From this revised framework, he introduces a "correction tensor" -- a mathematical tool that accounts for drag and resistance acting on particles of any shape, including spheres and thin discs. Importantly, the method does not rely on empirical fitting parameters.

Source: ScienceDaily

Scientists turn sunflower oil waste into a powerful bread upgrade

 As interest grows in healthier alternatives to traditional wheat-based foods, scientists are exploring new ingredients that can improve nutrition without sacrificing practicality. One promising option is partially defatted sunflower seed flour (SF), a material left behind after sunflower oil is produced. This underused by-product has shown strong potential for enriching bread with protein, fiber, and antioxidant compounds.

"Our aim was to optimize the reuse of sunflower seed flour considering its high protein and chlorogenic acid content," says biologist Leonardo Mendes de Souza Mesquita, who is currently based at the Institute of Biosciences of the University of São Paulo (IB-USP) in Brazil. He is the lead author of a study published in ACS Food Science & TechnologyTesting Sunflower Flour in Bread Recipes

To evaluate how sunflower seed flour performs in baking, the research team prepared bread recipes that replaced wheat flour (WF) with sunflower seed flour (SF) at levels ranging from 10% to 60%. Each version was carefully analyzed for its chemical makeup, dough behavior, and the physical characteristics of the finished bread.

"Sunflower seed flour has been shown to contain a very high percentage of protein, from 40% to 66%, as well as dietary fiber, iron, calcium, and high levels of chlorogenic acid, a phenolic compound associated with antioxidant, anti-inflammatory, and hypoglycemic effects," Mesquita explains. He adds that using this by-product increases the nutritional value of bread while lowering the environmental footprint of sunflower oil production. Because it is sold cheaply to avoid disposal, sunflower seed flour is also a low-cost ingredient.

Major Gains in Protein and Antioxidants

The results showed clear nutritional improvements. Breads made with sunflower seed flour contained significantly more protein and fiber than standard wheat bread. At the highest substitution level, the bread reached 27.16% protein, compared with 8.27% in conventional bread. Antioxidant levels rose alongside protein content.

Antioxidant activity was measured using Trolox, a water-soluble analog of vitamin E that serves as a reference standard. The values recorded in sunflower flour breads were much higher than those seen in bread made entirely from wheat flour.

"The result reinforces the potential of sunflower seed flour to promote health benefits associated with reducing oxidative stress," says Mesquita. He also notes strong inhibition of digestive enzymes, including α-amylase (92.81%) and pancreatic lipase (25.6%), suggesting that bread containing SF or SFE may help slow the digestion of starches and fats.

Clean Processing and Food Safety

Another key finding involves how sunflower oil is produced. According to the researchers, industrial extraction relies on mechanical pressing rather than chemical solvents. As a result, the leftover flour is free from processing contaminants, aside from residues already present from agricultural sunflower cultivation.

Source: ScienceDaily

Gut bacteria can sense their environment and it’s key to your health

 

The gut microbiome, also called the gut flora, plays a vital role in human health. This enormous and constantly changing community of microorganisms is shaped by countless chemical exchanges, both among the microbes themselves and between microbes and the human body. For these interactions to work, gut bacteria must be able to detect nutrients and chemical signals around them. Despite their importance, scientists still know relatively little about the full range of signals that bacterial receptors can recognize.

A key question remains. Which chemical signals matter most to beneficial gut bacteria?

Moving Beyond Pathogens in Microbiology Research

Until now, much of what scientists understand about bacterial sensing has come from studying model organisms, especially disease-causing bacteria. Far less attention has been given to commensals, the non-pathogenic or beneficial microbes that naturally live in the human body. This gap has left researchers wondering what kinds of chemical information these helpful bacteria are actually detecting in their environment.An international research team led by Victor Sourjik set out to address that question. The group included scientists from the Max Planck Institute for Terrestrial Microbiology, the University of Ohio and the Philipps-University Marburg. Their work focused on Clostridia, a group of motile bacteria found in large numbers in the human gut that are known to support gut health.

Gut Bacteria Detect a Wide Range of Nutrients

The researchers found that receptors from the human gut microbiome can recognize a surprisingly broad array of metabolic compounds. These substances include breakdown products from carbohydrates, fats, proteins, DNA, and amines. Through systematic screening, the team also identified clear patterns. Different types of bacterial sensors showed distinct preferences for certain classes of chemicals.

This finding revealed that gut bacteria are not responding randomly to their environment but are selectively tuned to specific metabolic signals.

Lactate and Formate Stand Out as Key Signals

By combining laboratory experiments with bioinformatic analysis, the researchers identified multiple chemical ligands that bind to sensory receptors controlling bacterial movement. These receptors help motile bacteria detect nutrients that are especially valuable for growth. The results suggest that movement in these bacteria is primarily driven by the search for food.

Among all the chemicals tested, lactic acid (lactate) and formic acid (formate) appeared most frequently as stimuli. This suggests that these compounds may serve as especially important nutrient sources for gut bacteria.

Cross-Feeding Supports a Healthy Microbiome

Some gut bacteria can produce lactate and formate themselves, highlighting the importance of 'cross-feeding'. In this process, one bacterial species releases metabolites that other species use as food. This kind of cooperation helps stabilize the gut ecosystem.

Source: ScienceDaily