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Niche-specific dermal macrophage loss promotes skin capillary ageing

Abstract All mammalian organs depend on resident macrophage populations to coordinate repair and facilitate tissue-specific functions 1–3 . Functionally distinct macrophage populations reside in discrete tissue niches and are replenished through a combination of local proliferation and monocyte recruitment 4,5 . Declines in macrophage abundance and function have been linked to age-associated pathologies, including atherosclerosis, cancer and neurodegeneration 6–8 . However, the mechanisms that coordinate macrophage organization and replenishment within ageing tissues remain largely unclear. Here we show that capillary-associated macrophages (CAMs) are selectively lost over time, contributing to impaired vascular repair and reduced tissue perfusion in older mice. To investigate resident macrophage behaviour in vivo, we used intravital two-photon microscopy in live mice to non-invasively image the skin capillary plexus, a spatially well-defined vascular niche that undergoes rarefication and functional decline with age. We find that CAMs are lost at a rate exceeding capillary loss, resulting in macrophage-deficient vascular niches in both mice and humans. CAM phagocytic activity was locally required to repair obstructed capillary blood flow, leaving macrophage-deficient niches selectively vulnerable under homeostatic and injury conditions. Our study demonstrates that homeostatic renewal of resident macrophages is less precisely regulated than previously suggested 9–11 . Specifically, neighbouring macrophages do not proliferate or reorganize to compensate for macrophage loss without injury or increased growth factors, such as colony-stimulating factor 1 (CSF1). These limitations in macrophage renewal may represent early and targetable contributors to tissue ageing.

Improving prediction region accuracy in marine animal movement with temporal fusion transformer

Abstract Predicting marine animal movements from satellite tracking data remains challenging, limiting conservation and ecosystem management efforts. To address this, we trained the Temporal Fusion Transformer (TFT) neural network on tracking data from 434 southern elephant seals to forecast locations and fill data gaps (imputation) within 7-day windows. Compared to state-space models, TFT reduced location errors by 15% and produced more efficient prediction regions, identifying where seals were likely to be found while using less area: a fivefold reduction for forecasting and 30–40% reduction for imputation. The model performed best near the continental shelf and at low-to-moderate movement speeds, with bathymetry, water temperature and current direction being the most influential environmental factors affecting the model output. When applied to new geographic regions not represented in the training dataset, model performance declined by approximately 30% across most evaluation metrics, indicating challenges in transferring learned patterns to unfamiliar environments. Our findings show that deep learning is a promising tool for analyzing large, sparse tracking datasets. The enhanced predictive capabilities have potential for dynamic conservation measures, such as forecasting the spatial evolution of animals to minimize conflicts with human activities and environmental disturbances.

Who gets included? A scoping review protocol of digital health interventions for older adults with heart failure through an equity lens

Introduction Heart failure is a common and progressive condition that significantly impacts older adults, leading to increased morbidity, reduced quality of life, and healthcare utilization. As its prevalence continues to rise, there is a need for effective management strategies tailored to this population. Digital health interventions (DHIs) have emerged as promising tools for managing chronic conditions like heart failure, potentially improving accessibility and personalizing care. However, there is limited understanding of the inclusivity and effectiveness of these interventions across diverse subgroups of older adults, particularly those differentiated by age, cognitive status, socioeconomic status, sex/gender, and race/ethnicity. Methods This protocol outlines a scoping review to assess the extent of literature on DHIs for managing heart failure among older adults, focusing on the representation of diverse subgroups and the characteristics of the interventions. Specifically, the review will explore which populations are included in current DHIs, how they are represented, and how intervention characteristics influence participation and outcomes. This scoping review will follow the Joanna Briggs Institute methodology for scoping reviews, using the PROGRESS-Plus framework to assess equity-related factors such as socioeconomic status, race/ethnicity, geographic location, and cognitive status. The review will focus on randomized controlled trials published between January 1, 2005, and the present, in high-income countries. Conclusions The forthcoming scoping review will provide a comprehensive mapping of the existing literature on digital health interventions for heart failure management in older adults, focusing on the inclusivity of diverse subgroups. By identifying gaps in the representation of key demographic factors such as age, cognitive status, socioeconomic status, sex/gender, and race/ethnicity, the review will highlight areas for future research and inform the development of more equitable, effective digital health solutions for heart failure. The findings will be valuable for healthcare practitioners, policymakers, and researchers seeking to improve the accessibility and impact of DHIs in managing heart failure among older populations.

Synergistic effects of syzygium cumini sawdust biochar and poultry manure on soil quality enhancement, nitrogen, organic carbon dynamics, and Amaranthus cruentus growth

Effects of music intervention on golf-specific skill performance of golfers under mental fatigue: Protocol for a randomized controlled trial

Given that golf tournaments last approximately five hours without an intermission, mental fatigue has become a critical factor affecting performance. Although research has shown that music intervention can effectively alleviate mental fatigue, this method has yet to be applied in golf. Therefore, this study aims to evaluate the effects of music intervention on golf-specific skill performance under mental fatigue. This study adopts a randomized, controlled, partially-blind design, including three groups. The MF-Mu group undergoes a mental fatigue induction task followed by a music intervention. The MF-nMu group completes the same mental fatigue task but does not receive the music intervention. The CON group serves as the control and receives neither the mental fatigue task nor the music intervention. Controlled variables include immersion tendency, sport anxiety, attention, motivation, and perceived exertion. Primary outcome measures include mental fatigue, driving shot, iron shot, chipping shot, and putting performance. Performance measures include accuracy and shot quality. In this study protocol, the use of smartphones for music intervention enhances its portability, allowing the intervention to be initiated or terminated at any time, increasing its flexibility and acceptability. Moreover, briefly listening to music during non-striking moments complies with golf regulations, making this study highly practical. It provides an effective strategy for golfers to manage mental fatigue in competitive environments. Trial registration ClinicalTrials.gov NCT06952283

Regulation of tumor hypoxic microenvironment by cyanobacteria-photosensitizer hybrid bioplatform for enhanced photodynamic therapy

Housing environment bilaterally alters transcriptomic profile in the rat hippocampal CA1 region

Brain asymmetry is a fundamental feature of neural organization. However, the molecular basis of hippocampal lateralization in response to environmental stimuli remains poorly understood. Here, we examined the transcriptomic profiles of the left and right hippocampal CA1 regions in rats reared under isolated or enriched housing conditions to elucidate hemisphere-specific responses and shared molecular adaptations. RNA-sequencing analysis revealed lateralized differences in the number and identity of differentially expressed genes, accompanied by distinct biological themes, as indicated by overrepresentation and gene set enrichment analysis. The left CA1 region was prominently engaged in pathways related to synaptic organization and mitochondrial function, whereas the right CA1 region exhibited enrichment in transcriptional regulation and RNA metabolic processes. Despite these asymmetries, co-expression and protein–protein interaction network analyses revealed shared molecular architectures. Immediate early genes formed consistent central hubs across both hemispheres, and a common Mecp2–Grin2b–Cdkl5–Tet3 protein interaction cluster was identified as a potential integrative regulatory module. Additional enrichment analysis of differentially expressed genes shared between hemispheres further highlighted conserved responses, particularly in synaptic plasticity and cell–cell communication. Together, these findings demonstrate that the left and right CA1 regions employ distinct yet partially convergent transcriptional programs to adapt to environmental stimuli. This coordinated molecular asymmetry provides novel insights into hippocampal lateralization and its role in experience-dependent brain plasticity.

Accuracy of seven criteria based on cholesterol and lactate dehydrogenase for differentiating exudative and transudative pleural effusions

The impossible confounder: Quantifying the limits of alternative explanations for COVID-19 vaccine effectiveness

Background Observational studies have consistently reported large reductions in COVID-19 risk among vaccinated individuals. However, critics have raised concerns that unmeasured confounding may entirely explain these associations. Methods We combined the classical Cornfield inequality with a Monte Carlo sensitivity analysis to evaluate whether unmeasured confounding alone could plausibly account for the observed effectiveness of COVID-19 vaccines. The Cornfield inequality provides a lower bound on the strength of confounding required to explain a given association. The Monte Carlo analysis simulates uncertainty over possible confounder–exposure and confounder–outcome relationships by drawing from weakly informative prior distributions, allowing us to estimate the frequency with which such confounding would be sufficient. Results For an observed risk ratio of 0.08—consistent with early estimates for the Pfizer-BioNTech vaccine—the confounder would need to be both highly imbalanced (e.g., 10 times more prevalent among vaccinated individuals) and strongly protective (e.g., reducing disease risk by 99%). Simulation results showed that, under the specified assumptions, fewer than 2% of draws satisfied this condition. Even in the more moderate case of a risk ratio of 0.25 (e.g., AstraZeneca), the proportion remained below 6%. Conclusions Our findings suggest that while residual confounding may attenuate effect estimates, it is statistically and epidemiologically implausible that unmeasured confounding alone could fully account for the magnitude of observed vaccine effectiveness. This framework combines the falsificatory logic of Cornfield bounds with the flexibility of simulation-based sensitivity analysis, providing a transparent tool for evaluating confounding-based explanations in observational research.

Numerical analysis and optimization of continuous texture geometries in thermo-hydrodynamic journal bearings

Abstract Journal bearings play a critical role in many engineering systems, where their performance directly affects operational efficiency and reliability. This study investigates the effect of surface texturing on the thermo-hydrodynamic (THD) behavior of journal bearings with the goal of enhancing load-carrying capacity (LCC). Departing from conventional dimple-based textures, five continuous texture shapes are introduced and systematically analyzed using COMSOL Multiphysics. The thermo-hydrodynamic model is validated against the experimental data of Ferron, J., Frene, J. & Boncompain, R. A study of the thermohydrodynamic performance of a plain journal bearing comparison between theory and experiments. (1983). Optimization of texture parameters including height and distribution in both axial and circumferential directions is performed numerically using the Monte Carlo method. The study also evaluates the impact of texture placement in three distinct regions of the bearing surface. Results show that optimized continuous textures significantly outperform smooth bearings, achieving up to 144% increase in LCC. These findings offer new insights into texture design for high-performance journal bearings under thermal and hydrodynamic constraints.

SARS-CoV-2 detection is independent of microbiome composition on surfaces in a major Ontario hospital

The SARS-CoV-2 pandemic has resulted in considerable mortality in hospital settings. Built environment surveillance can provide a non-invasive indicator of SARS-CoV-2 status in hospitals, but we have a limited understanding of SARS-CoV-2’s microbial co-associations in the built environment, including any potential co-occurrence dynamics with pathogenic and antimicrobial-resistant microorganisms. Here we examine the microbial communities on floors and elevator buttons across several locations in two major tertiary-care Ontario hospitals during a surge in SARS-CoV-2 cases in 2020. Total microbial community composition, prevalence and type of detected antimicrobial resistance genes, and virulence factor distributions were governed by sample source rather than SARS-CoV-2 detection status. Fifteen microorganisms were identified as indicator species associated with positive SARS-CoV-2 signal, including three opportunistic pathogens (i.e., two Corynebacterium sp. and a Sutterella sp). Key clinically relevant antimicrobial resistance genes showed varying prevalence across sites within the hospital, suggesting that our workflow could inform resistance burden in hospitals. Overall, these results indicate limited or only weak interactions between microbiome composition and SARS-CoV-2 detection status in the hospital built environment.

Durability and service life prediction of fly ash based geopolymer high performance concrete under extreme environmental conditions

Matrix stiffness influences drug resistance to gemcitabine analog and AZD 1775 combination in PDAC organoids

Background Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers, with limited therapeutic advancements and rapid development of treatment resistance. Fatty acid-conjugated gemcitabine analogs have shown improved antitumor efficacy. This study investigates the effects of gemcitabine conjugated with caprylic acid (Gemcitabine-8C) in combination with AZD 1775, a WEE1 inhibitor, using patient-derived PDAC organoids. Methods Patient-derived PDAC cells (G43, G46) were cultured in a gelatin-based 3D organoid system with tunable stiffness to mimic the tumor microenvironment. Cells were treated with gemcitabine, Gemcitabine-8C, AZD 1775, or their combination. The study assessed treatment efficacy, extracellular matrix influence, morphology, gene expression, and drug resistance mechanisms. Results The combination of AZD 1775 and Gemcitabine-8C significantly enhanced treatment efficacy compared to monotherapies or gemcitabine with AZD 1775. G43 cells were more sensitive to treatment than G46. Increased matrix stiffness correlated with greater drug resistance. Resistant cells exhibited elevated oxidative stress, while sensitive cells showed F-actin structural alterations absent in resistant counterparts. Conclusions AZD 1775 enhances the efficacy of Gemcitabine-8C at non-toxic doses, demonstrating its potential for overcoming PDAC treatment resistance. The cell origin and tumor microenvironment plays a key role in modulating drug response, highlighting the need for microenvironment and individualized-targeted strategies.

Nepenthes pitcher plant inspired bio-polymer embedded porous surfaces for oil aquaplaning

Abstract The Nepenthes pitcher plant has inspired surfaces employing a liquid barrier that shields the surface from contaminants. However, such liquid-infused oil-repellent surfaces employ toxic fluorocarbons or unstable polar liquids. Here, we develop a bio-friendly oil-repellent surface using a food-grade bio-polymer coating on a nanoporous surface. By mimicking the pitcher plant’s nectar lining, the food-grade polymer absorbs water enhancing its stability against drainage and evaporation. The water-based lubricant is non-toxic, compatible with humid environments and replenishes simply by exposure to nebulized water droplets. Our surfaces demonstrate lubrication-induced oil and solid repellence and have substantial transformative potential in applications like oil-water separation, anti-fouling and food packaging.

The moderating role of father involvement in the association between maternal depression and child nutrition: A cross-sectional study in rural Malawi

This study highlights the critical role of fathers in improving child dietary diversity in low-resource setting, particularly in the context of maternal mental health challenges. Using cross-sectional data of 333 mother-father-child triads in rural Malawi, we examine the association between paternal involvement and child dietary diversity among children aged between 24–60 months. Our findings show that greater father involvement is significantly associated with higher child dietary diversity scores, even after accounting for maternal depressive symptoms. Importantly, we identify a significant interaction between father involvement and maternal depressive symptoms: paternal engagement buffer the negative effects of maternal mental health challenges on children’s diets. However, father involvement does not correlate with household-level dietary diversity, suggesting that paternal contributions are targeted specifically toward children- primarily through the reallocation of nutrient-rich, animal-sourced foods. These results underscore the importance of culturally sensitive, family-centered nutrition interventions that actively engage fathers while addressing maternal mental health to improve child nutrition outcomes in low-resource contexts.

Spatial metabolic gradients in the liver and small intestine

Single-cell transcriptomic analysis reveals distinct cancer-associated fibroblast signatures in treatment-refractory esophageal squamous cell carcinoma

Forage preference in two geographically co-occurring fungus gardening ants: A dietary DNA approach

Traditional methods of forage identification are impractical with non-leafcutting fungus gardening ants, making diet-related ecological and life history questions difficult to study. To address this limitation, we utilized dietary DNA metabarcoding on excavated ant fungus gardens to generate forage diversity metrics for the two co-occurring species Trachymyrmex septentrionalis and Mycetomoellerius turrifex . Ten fungus garden samples from each species were collected from a 60x70 m plot in East Texas. Each of the colonies we sampled was paired with a colony from the other species within 3 m of it. Plant forage diversity was assessed with chloroplast trnL primers, and insect frass forage diversity was assessed with mitochondria COI primers. DNA metabarcoding identified a total of 44 plant taxa across all samples, but performed poorly when characterizing foraged insect frass. Plant beta diversity was significantly different between the gardens of T. septentrionalis and M. turrifex colonies, as well as paired colonies. Colony pairs also had significantly different plant alpha diversity. This indicates that diet preference is likely driven both by ant species-specific plant preference, and colony location-specific plant resource availability. Overall, our results show that dietary DNA techniques are a promising tool for the identification of plant forage in ant fungus gardens, enabling the study of future diet-based ecological and natural history questions.

Exploring complex dynamics in nonlinear Riemann wave models using fractional calculus-based expansion

Thyroarytenoid muscle fiber orientation regulates the ability to modulate vocal fold vertical thickness

While all speakers modulate their voice quality, some speakers do so more easily than others. Previous studies suggest that the ability to modulate voice quality depends on the ability to control vocal fold medial surface vertical thickness, among other factors. While it is well known that vocal fold vertical thickness can be increased by an inferior medial bulging of the vocal folds due to actions of the thyroarytenoid (TA) muscle, the underlying mechanism of how TA muscle activation produces inferior medial bulging remains unclear. In this computational study, we show that the TA muscle fiber orientation had a large effect on the extent of inferior medial bulging and vertical thickness increase under TA muscle contraction in a three-dimensional model of laryngeal muscle activation based on high-resolution magnetic resonance imaging. Maximum inferior medial bulging and thickness increase occurred when the TA muscle fiber orientation angle ranged between 22–32° relative to the anterior-posterior direction. At these optimal fiber angles, TA muscle activation was able to induce a horizontal rotation of the arytenoid cartilage, which medialized the vocal process and the inferior portion of the medial surface more than the superior portion of the medial surface, thus increasing vertical thickness. In contrast, the lateral cricoarytenoid muscle induced a rocking rotation of the arytenoid cartilage, which medialized the superior medial surface slightly more than the inferior medial surface, and thus had an opposite and much-reduced effect on vocal fold thickness. It is hypothesized that potential individual differences in TA muscle fiber orientation may contribute to individual differences in the ability to modulate voice quality.