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Long-wavelength emission and excimer formation for PCBM in solutions and polymer matrices
No full textThe present study explores the excited-state relaxation of PCBM (phenyl-C61-butyric acid methyl ester) fullerene derivatives in various organic environments, with a focus on the influence of molecular aggregation. A comparative analysis was performed on PCBM solutions in acetonitrile and toluene, as well as in solid matrices - polystyrene (PS) and poly(methyl methacrylate) (PMMA). A comprehensive study of linear optical properties has been performed, including absorption spectra, steady-state photoluminescence (PL) spectra, kinetics of PL decay, and PL lifetimes. The study shows that, depending on the environment and the degree of aggregation, PCBM exhibits distinct emission features arising from monomer species as well as from different types of aggregates, mainly from complexes such as excimers within the long-wavelength region of 650–850 nm. It has been shown that monomeric forms of PCBM exhibit short lifetimes in acetonitrile solution, whereas excimer complexes in toluene solution and polymer matrices are characterized by longer lifetimes. The results presented herein contribute to the understanding of the nature of long-wavelength luminescence in PCBM and can be used in the development of organic photovoltaic and optoelectronic devices
Parent reports of eating behaviour and feeding practices: effects of parent and child sex
Full text linkResearch on parental feeding practices has focused on mothers, often overlooking fathers’ perspectives and the influence of child sex. This study examined (1) differences between fathers’ and mothers’ own eating behaviours, their use of feeding practices, and perceptions of their children’s eating behaviours, and (2) the role of child sex in these perceptions and practices. Parents (N=784; 145 fathers and 639 mothers) of preschoolers (3-5 years, 51.3% female) from the UK completed an online survey assessing their eating behaviours and feeding practices, and their child’s eating behaviours. There were significant sex differences in parents’ eating behaviours, with mothers reporting more emotional overeating, hunger, satiety responsiveness, and slowness in eating. Mothers and fathers did not differ in their reports of children’s eating behaviours. Girls were reported to have higher levels of satiety responsiveness than boys. When exploring the interaction of parent and child sex in reports of eating behaviour, fathers reported that girls had more desire to drink. Mothers and fathers differed in their reported use of some feeding practices. Both mothers and fathers reported greater use of food for emotion regulation with girls than boys. Fathers used more encouragement of balance and variety with boys. These findings highlight distinct patterns in feeding practices and eating behaviours, influenced by both parent and child sex, suggesting that girls may be at greater risk of receiving feeding practices that contribute to the development of emotional eating. These results emphasize the need to consider the role of sex in future research and the development of tailored feeding guidance
Reinvigorating the Micro Foundations of Human Resource Management (HRM): A Narrative Review
No full textAdvanced optical phantom mimicking microvascular and directed blood flow in mouse brain
Full text linkThe accurate replication of cerebral hemodynamics is essential for advancing neuroimaging techniques and preclinical research. This study presents a novel multi-component dynamic optical phantom designed to model the complex blood flow dynamics of the mouse brain. The phantom incorporates a static base mimicking skull optical properties, a porous medium infused with a blood-mimicking solution to simulate microvascular perfusion, and a directed flow channel representing large vessels such as the sagittal sinus. The phantom structure was characterized using laser speckle contrast imaging (LSCI) to assess its ability to replicate in vivo-like blood flow patterns. The results demonstrate strong quantitative agreement between the phantom and transcranial LSCI measurements of mouse brain hemodynamics. Our key findings highlight the influence of tissue-mimicking perfusion structures and optical attenuation properties on the blood flow index, validating the phantom as a reproducible and physiologically relevant model. This optically tunable and dynamically controllable platform provides a robust tool for calibrating neuroimaging technologies, validating new optical diagnostic techniques, and investigating cerebral blood flow regulation in preclinical studies
Adult organotypic brain slice cultures recapitulate extracellular matrix remodeling in hemorrhagic stroke
Full text linkHaemorrhagic stroke is a devastating condition characterized by vessel rupture and free blood within the brain parenchyma or cerebrospinal fluid (CSF) filled spaces. Across the major subtypes of hemorrhagic stroke (subarachnoid, intracerebral, and intraventricular hemorrhages), the presence of blood in the CSF generates significant tissue damage in the first 72 h after the event, known as early brain injury (EBI). EBI includes neuroinflammation, blood-brain barrier breakdown and dysregulation of extracellular matrix (ECM) dynamics. ECM dysfunction has been shown to trigger fibrosis of the cortical blood vessels, limiting normal CSF circulation and resulting in the buildup of metabolic waste or the development of post-hemorrhagic hydrocephalus. Limiting or preventing this fibrosis may therefore reduce the rate of morbidity experienced by survivors, providing a potential avenue for non-surgical treatment to reduce secondary brain injury post-stroke. Despite this, current in vivo approaches fail to differentiate between the effect of blood products and secondary consequences including intracranial pressure (ICP) elevation and mass effect. Here, we describe an adult rat organotypic brain slice culture (OBSC) model of hemorrhagic stroke which enables the identification of the effect of blood products on ECM dysregulation. We demonstrate the distribution of key cell types across a time course of 0, 3 and 7 days in culture, indicating that such cultures are viable for a minimum of 7 days. Using immunofluorescence staining, Western blotting and RNA sequencing, we show that exposure of OBSCs to lysed blood markedly increases ECM deposition around cortical blood vessels. This is accompanied by dysregulation of ECM regulatory genes and upregulation of inflammation and oxidative stress-related genes, successfully recapitulating the changes seen in human stroke survivors. This versatile ex vivo model provides a translational platform to further understanding of hemorrhagic stroke pathophysiology and develop or trial novel therapeutics prior to progression to in vivo stroke studies
Risk of Cancer Comparing Warfarin and Direct Oral Anticoagulants: Population-Based Cohort Studies in England and Hong Kong
No full textPrevious evidence suggests a potential protective effect of warfarin against cancer, compared to non-users. However, it may be prone to immortal time bias and residual confounding. We aimed to examine the association between cancer and warfarin, compared with active comparator (direct oral anticoagulants). We conducted studies using population-based databases from England and Hong Kong to investigate the association between warfarin and hazard of cancer using a new-user active-comparator cohort design. People with atrial fibrillation aged ≥ 18 years who had first received anticoagulant treatment during 01/01/2011-31/12/2019 were involved. No evidence supported the association between warfarin and hazard of overall cancer, compared with direct oral anticoagulants in both settings (England: hazard ratio [HR] = 1.03, 95% confidence interval [CI] 0.94-1.13; Hong Kong: HR = 0.89, 95% CI 0.79-1.01). A lower hazard of female breast (HR = 0.49, 95% CI 0.30-0.79), ovarian (HR = 0.07, 95% CI 0.01-0.58), and pancreatic (HR = 0.46, 95% CI 0.22-0.96) cancers and a higher hazard of kidney cancer (HR = 3.57, 95% CI 1.64-7.76) were found in Hong Kong, comparing warfarin with direct oral anticoagulants, but these were not replicated in England. This study does not find a protective effect of warfarin against cancer versus direct oral anticoagulants. The risks of site-specific cancers including pancreatic, kidney, and sex-specific cancers between oral anticoagulants shown in the Hong Kong setting only may require further investigation in other independent datasets
Auditing Demographic Bias in Mistral: An Open-Source LLM’s Diagnostic Performance on the MedQA Benchmark
Full text linkThe application of large language models (LLMs) within clinical decision-support frameworks is receiving growing research attention, yet their fairness and demographic robustness remain insufficiently understood. This study introduces MedQA-Demog, a purpose-built, label-invariant extension of the MedQA-USMLE benchmark, designed to enable systematic auditing of demographic bias in medical reasoning models. Using a deterministic augmentation framework, we generated 4,659 question-answer items that incorporated counterfactual variations in gender, race/ethnicity, and age, and validated them through automated integrity and balance checks. We evaluated the Mistral 7B-Instruct model under stochastic (temperature = 0.7) and deterministic (temperature = 0.0) inference rules via the Ollama local environment, applying Wilson's 95 % confidence intervals, χ²/z-tests, McNemar’s paired analysis, and Cohen’s h effect sizes to quantify fairness. Across all demographic variants, diagnostic accuracy remained consistent (Δ 0.05), and all performance gaps fell within Minimal or Low Bias thresholds. Confusion-matrix and prediction-balance analyses revealed no systematic over- or under-prediction patterns, while power analysis confirmed that observed fluctuations were below the minimum detectable effect (≈ 0.057). A stratified robustness analysis further confirms that these fairness patterns persist across question difficulty levels and are not an artefact of uniformly limited performance. These findings demonstrate that open-weight, instruction-tuned LLMs can maintain demographic stability in clinical reasoning when evaluated through reproducible, controlled pipelines. This framework provides a practical foundation for bias evaluation in open clinical LLMs, supporting their ethical integration into digital health tools and clinical decision-support systems
Neuro-lymphaphotonics opens new horizons of the future technologies for the therapy of brain diseases
Full text linkPharmacological treatment of brain diseases is hampered by the blood-brain barrier that prevents the vast majority of drugs from entering the brain. For this reason, the pharmaceutical industry is reluctant to invest in the development of new neurotropic drugs. Even if effective pharmacological strategies for the treatment of brain diseases will be found, it will take 10-15 years between the emergence of an idea and the introduction of a drug to the market. This creates priority for the development of neuro-lymphaphotonics based on the development of promising non-pharmacological strategies for managing functions of the meningeal lymphatic vessels (MLVs). MLVs play a crucial role in the removal of toxins and metabolites from brain as well as in regulation of brain homeostasis and its immunity. Since MLVs are located on the brain surface, light penetrating the skull easily reaches MLVs and affects their functions. Therefore, MLVs are an ideal target for photobiomodulation (PBM). The pioneering studies have shown that PBM of MLVs is a promising strategy for the treatment of a wide range of neuropathology, including Alzheimer's or age-related brain diseases, brain tumor, intracranial hemorrhage, brain damages caused by diabetes. It has recently been discovered that sleep enhances the therapeutic effects of PBM and is a "therapeutic window" in overcoming the limitations of PBM in the elderly. Considering that the PBM technologies are non-invasive and safe with commercially viable possibilities (portability and low cost), neuro-lymphaphotonics open up promising prospects for the development of future technologies for the effective therapy of brain diseases
Design and development of heat pipe cooling systems for air & watertight Portable Energy Storage units
Full text linkPortable Energy Storage (PES) units play a vital role in delivering reliable and sustainable energy solutions, particularly in regions with limited grid access or challenging environmental conditions that require special Ingress Protection (IP) considerations, such as air and watertight designs without vents. Thermal management is a critical challenge for such PES units, especially for key components such as inverters and battery packages, which are prone to overheating. This study explores the integration of heat pipe-based cooling systems with heatsinks as an effective thermal management solution. A 1-kW PES was designed, developed and assessed as a case study under varying ambient temperatures and operational scenarios. Both free and forced convection cooling methods were evaluated through experiments and validated simulations. Results show that under free convection at an ambient temperature of 23 °C, Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) remained below 70 °C, while Lithium-ion Batteries (LIBs) stabilized at 60 °C. Forced convection with 1.4 W fans significantly improved cooling efficiency, reducing temperatures by 25–45 %, depending on ambient conditions. At 23 °C, a 33 % temperature reduction was observed in both MOSFETs and LIBs. At an ambient temperature of 50 °C, MOSFETs were maintained at 70 °C, and LIBs remained below 60 °C for ambient temperatures up to 45 °C. These findings confirm that heat pipe cooling systems, combined with forced convection, offer an effective thermal management solution for compact, air and watertight PES applications
Cognitive Functioning in Phenylketonuria:A Lifespan Perspective
Full text linkPhenylketonuria (PKU) is a hereditary metabolic disorder characterized by the inability to metabolize phenylalanine, leading to neurotoxic accumulation of phenylalanine and significant cognitive impairment. While extensive research has focused on the cognitive outcomes in middle childhood, adolescence, and early adulthood, there is a notable paucity of studies addressing the cognitive functioning of very young and older PKU patients. This review underscores the necessity for further research in these populations, particularly because of the importance of early cognitive development for later cognitive and behavioral functioning and because of the potential implications of PKU and metabolic control for age-related cognitive decline
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