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Effects of graded-porosity gas diffusion layers used in polymer electrolyte fuel cells
Get PDFOptimising the design of gas diffusion layers (GDLs) is essential to enhance water management and reactant transport in polymer electrolyte fuel cells (PEFCs), which are critical renewable energy conversion technologies required to decarbonise electricity. In this work, a comprehensive three-dimensional model of a PEFC has been developed to analyse the sensitivity of fuel cell performance to graded-porosity cathode GDLs under various humidity conditions and GDL thicknesses. The results show that, for most humidity conditions, the fuel cell performs best when the cathode GDL has low porosity at the catalyst interface and high porosity at the bipolar plate interface. Under relatively low humidity conditions, fuel cell performance deteriorates when using graded-porosity GDLs with higher porosity near the catalyst layer. On the other hand, under high humidity conditions, a cathode GDL with a porosity gradient improves performance compared to a GDL with uniform porosity. Further, when the GDL thickness is reduced from 300 μm to 200 μm, the best performance is achieved with a GDL that has higher porosity near the catalyst layer. These findings are discussed and justified in the study providing valuable guidance for designing advanced GDL structures to improve PEFC efficiency, supporting their wider adoption in renewable energy systems
Anatomy of a Stalemate: Making Sense of the EU-UK Youth Mobility Controversy
Get PDFThis policy commentary explores the puzzling stalemate over a proposed Youth Mobility Scheme (YMS) between the European Union (EU) and the United Kingdom (UK), offering a deep analysis of its emergence as a site of post-Brexit contestation. Despite appearing as a low-stakes, mutually advantageous initiative, youth mobility became mired in mutual misperceptions, political caution, and institutional rigidity. Drawing on the conceptual triad of bounded rationality, path dependence and bilateralism, the policy commentary traces how misaligned expectations, historical baggage and diverging preferences for multilateral versus bilateral approaches have locked both sides into intransigent positions. Rather than reflecting irreconcilable interests, the impasse reveals how these constraints continue to shape - and distort - the initial stages of policy cooperation. As such, understanding this stalemate not only sheds light on missed opportunities for young people on both sides of the Channel, but also offers critical lessons for the future architecture of UK-EU engagement
Evaluating long-term thermal performance and soil recovery in energy piles under various operational modes
Get PDFEnergy piles present a feasible solution for heating and cooling decarbonisation and offer economic advantages. However, their widespread adoption is constrained by limited understanding of long-term performance. This study employs a validated, fully coupled three-dimensional thermo-hydro-mechanical numerical model to investigate long-term thermal performance of energy piles under different operational strategies. The model examines continuous operation (Mode 1), seasonal stoppage (Mode 2), and an idealised daily stoppage mode (Mode 3) over both short-term (1-year) and long-term (10-year) cycles. Results show that daily stoppage (Mode 3) limits cumulative soil temperature drift to ±2 °C after ten years, compared to over 6 °C under continuous loading. Mode 3 also yields the most stable outlet fluid temperatures, outperforming Mode 1 by up to 2 °C in cooling efficiency. Thermal impacts are spatially confined, with 90 % of recovery occurring within a 4 m radius from the pile. Mode 3, as an ideal operational strategy, establishes a performance benchmark for ground recovery and system energy efficiency. These findings highlight the importance of load scheduling in mitigating ground thermal degradation and enhancing long-term performance. The results provide a basis for integrating energy piles into seasonal thermal storage or hybrid heating systems and guiding future smart control strategies
Antipsychotic Prescribing Trends in England: The Role of Regional Disparities, Health Inequalities, and Ethnic Density
Get PDFBackground: Antipsychotics are essential for managing certain mental disorders; however, little is known about regional disparities in their prescribing or how these patterns are shaped by ethnic density and health inequalities. Aims: To analyse national, regional and local integrated care board trends in antipsychotic prescribing in England from April 2019 to March 2025, and to explore their associations with health inequalities and ethnic density. Method: A population-level observational study was conducted using the English primary care prescription data from OpenPrescribing. Linear regression was used to assess trends in first-generation (FGA), second-generation (SGA) and total antipsychotic prescribing. Generalised additive models examined associations between prescription rates and health inequalities and ethnic density at the local level. Results: Antipsychotic prescribing increased from 185.55 to 199.85 prescriptions per 1000 population between April 2019 and March 2025. SGA use increased significantly (168.48 to 186.27) whereas FGA use declined (17.08 to 13.58). Regional annual increases ranged from 3.85% (95% CI = 3.53%, 4.16%) in London to −0.21% (95% CI = −0.72%, 0.31%) in the South-West region, with greater variation at the local level, from 6.62% (95% CI = 5.71%, 7.53%) in North Central London to −2.05% (95% CI = −2.71%, −1.40%) in Shropshire, Telford and the Wrekin. Higher Pakistani ethnic density was associated with lower prescribing rates, whereas greater health inequalities were linked to increased prescribing. Conclusions: Antipsychotic prescribing patterns have shifted in recent years, with notable regional disparities influenced by health inequalities and ethnic composition. Targeted interventions are needed to promote equitable access and address prescribing disparities in mental healthcare
Nonlinear synchronization through vector subharmonic entrainment
Get PDFSynchronization is a universal phenomenon underpinning various natural processes and finds direct application in control engineering and photonics. Among several synchronization mechanisms, subharmonic entrainment (SHE) is a nonlinear synchronization phenomenon where an oscillator locks to an external drive with a fraction of the oscillator’s frequency. While its mechanism is well understood for scalar couplings and finds application in the stabilization of ultrafast laser pulses, the potential of SHE with vectorial coupling is still unexplored. In this work, we demonstrate vector SHE (VSHE) using a passively mode-locked fiber laser as a testbed. We unveil the mechanism of vector SHE, in which weak external signals can entrain internal laser dynamics through vector coupling. Vector SHE presents in the form of synchronization between the subharmonic of mode-locking-driven oscillations and continuous wave (CW) signal with an evolving state of polarization. This CW signal, driven by the internal dynamics of the injected signal, causes VSHE with the frequencies’ ratios of multiples of ten, resulting in a partially mode locking regime operation. Our findings offer new control techniques over mode-locking and additional dimension such as polarization states
Development of a deep neural network model for simultaneous analysis of extracellular analyte gradients for a population of cells
Get PDFDetecting the spatial release of extracellular nitric oxide (NO) is essential for understanding the dynamics in cell communication for physiological and pathological processes. This study presents an innovative methodology that integrates fluorescence-based sensing platforms utilizing single walled carbon nanotubes (SWNT) with machine learning models to expedite the spatial data analysis of extracellular analytes. The deep learning model You Only Look Once (YOLOv8) segmentation achieves accurate cell identification across diverse morphologies and clustered cell groups, with a recall of 98% and a precision of 83%. The spatial analysis of extracellular NO is achieved by extracting the cell contour coordinates from the YOLO-identified cells and translocating the boundaries onto SWNT fluorescence files. The model enables rapid analysis for multiple cells across numerous images, with 100 image pairs completed in just 68 s. The combination of nanotechnology with automated neural network-based cell detection establishes a robust sensing framework with pixel-level spatial resolution of NO dynamics, delivering critical insights into cellular communication and holding promising implications for diagnostic and therapeutic applications
Development of Biobased Poly(ether ester)s from Novel Lignin-Derived Monomers Present in Lignin Oils
No full textLignin, a naturally abundant and renewable aromatic polymer, remains vastly underexploited, despite its immense potential for sustainable materials development. Reductive catalytic fractionation of lignocellulosic biomass results in low-molecular-weight lignin oils. A large fraction of these oils consists of 4-n-propanolguaiacol (PohG) and 4-n-propanolsyringol (PohS) and is unexplored as polyester building blocks. In this study, 4-n-propanolphenol (PohP), PohG, and PohS were modified in AB monomers by reaction with bromoalkanoates with different alkyl chain lengths. The AB monomers were subsequently polymerized into poly(ether ester)s. The resulting polymers were characterized in-depth by size exclusion chromatography, nuclear magnetic resonance, (modulated) differential scanning calorimetry, wide-angle X-ray scattering, thermogravimetric analysis, and dynamic mechanical analysis and were subsequently successfully depolymerized by base catalysis to prove the recycling potential. The produced poly(ether ester)s have high molecular weights, and clear trends in the glass transition, melting temperature, and viscoelastic properties of the resulting polymers were observed in relation to the AB monomers. The poly(ether ester)s showed comparable thermal and viscoelastic properties to poly(butylene adipate-co-terephthalate) and poly(butylene adipate-co-furanoate) and represent a novel class of semiaromatic polyesters derived from lignin
Emerging role of 7-Ketocholesterol and hydroxylated 7-Ketocholesterol in the Pathophysiology of Disease
Get PDFCholesterol oxidation at the C7 position is a hallmark of non-enzymatic lipid peroxidation. Reactive oxygen species initiate hydrogen abstraction at the allylic C7 position of cholesterol, leading to the formation of 7-hydroperoxides, which subsequently decompose to yield 7-hydroxycholesterols and 7-ketocholesterol (7KC). Due to the relative chemical stability, 7KC accumulates preferentially and is commonly detected in biological samples, compared to more labile hydroperoxide intermediates. 7KC is known to induce oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress, leading to apoptosis, autophagy, or necrotic cell death depending on cell type and exposure conditions. In addition, 7KC promotes inflammatory pathways and membrane dysfunction, contributing to tissue damage in diseases associated with chronic oxidative stress. These mechanisms open opportunities for the development of targeted intervention strategies. Accumulation of 7KC also acts as a substrate that may undergo further metabolic or oxidative transformations. Importantly, cells possess enzymatic systems capable of introducing hydroxyl groups at the cholesterol side chain that 7KC can be further modified into double-substituted oxysterols (7-keto-25-hydroxycholesterol and 7-keto-27-hydroxycholesterol) combining a 7-keto moiety with side-chain hydroxylation. These metabolites of 7KC represent the dynamic interplay between oxidative damage and cellular sterol metabolic pathways. Elucidating their biological functions will be essential for a more comprehensive understanding of oxysterol biology in health and disease
The healthcare experiences and psychological support needs of adults and caregivers managing food allergy
Get PDFFood allergy (FA) related distress is common in patients and caregivers, however, there is little funding for psychological support within allergy clinics. As part of the Global Access to Psychological Services for Food Allergy (GAPS) study, we explored adults’ and caregivers’ experiences with healthcare services in the UK and their FA-related psychological support needs. Semi-structured interviews were carried out with 22 adults with FA and 14 caregivers of children with FA and analysed using template analysis. Three themes were constructed from the data: “Road to diagnosis and getting past the gatekeeper,” “Support for managing FA inside and outside the healthcare system” and “The need for a holistic healthcare approach.” There is need for greater understanding of FA, particularly within primary care. Access to psychological services within the multidisciplinary healthcare allergy team would provide patients and families with the holistic care they require and reduce the need for costly private services
A Qualitative Assessment of Metro Operators’ Internal Operations and Organisational Settings
Get PDFThis article offers a Qualitative Assessment of Metro Operators’ Internal Operations and Organisational Settings. It focuses on the current operational structures of metro companies and elaborates on key aspects incl. maintenance of metro rolling stock and energy consumption. Envisaging future metro operations requires a collective and collaborative approach to understand an operator’s requirements. This study aims to gain an understanding of the current status of metro operators, as well as to identify areas of future innovation and further development. A special emphasis was given to the organisational settings – an underexplored aspect of metro operators in existing research - in addressing three designated areas of interest: predictive maintenance, cyber-security and energy consumption. Therefore, to achieve an insight into metro operator’s internal operations, the study sought to engage in dialogue with operators. A literature review was first conducted to provide a foundation for analysis, and based on it, an online self-completed questionnaire survey was designed and administered to gain responses and insights from an extensive range of real-world metro operators. Follow-up face-to-face and group-wide discussions were also undertaken to obtain further detail and more specific information relating to metro operations. Through a three-dimension analysis framework, current practices, areas of consensus and future innovative strategies of metro operators’ internal operations and organisational settings are highlighted. These insights collectively underscore the importance of adaptable strategies and cross-sector collaboration for advancing resilient, efficient, and secure metro systems. The outcome of the paper aspires to provide a strong foundation for future research as well as for future metro projects, providing an overview of the existing status of metro operators across the world
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