Multidisciplinary Digital Publishing Institute (Switzerland)
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Association Among Serum Vitamin D Levels, Visual Field Alterations, and Optical Coherence Tomography Parameters: A Clinical Correlation Study
No full textVitamin D deficiency is increasingly recognized as a systemic factor influencing retinal health through inflammatory, neuroprotective, and vasculotropic pathways. Evidence regarding early retinal alterations in otherwise healthy adults remains limited. This cross-sectional study evaluated 120 eyes from 60 healthy adults stratified by serum 25(OH)D levels into <30 ng/mL (n = 60) and ≥30 ng/mL (n = 60). All subjects underwent optical coherence tomography (OCT), OCT angiography (OCTA), visual field testing, and contrast sensitivity assessment. Central macular thickness (CMT), ganglion cell complex (GCC) thickness, and perfusion density in the superficial and deep capillary plexuses (SCP, DCP) were compared between groups. Vitamin-D-insufficient eyes showed significantly reduced CMT (267.66 ± 13.31 µm vs. 274.69 ± 14.96 µm; p = 0.035). GCC thinning was significant only in the inner inferior nasal sector (70.7 ± 13.14 µm vs. 76.45 ± 12.12 µm; p = 0.030), whereas other GCC sectors were comparable between groups. Perfusion density was lower in the DCP across whole, inner, and outer regions (all p < 0.001) and in the SCP inner (p = 0.027) and outer (p = 0.009) regions, while whole SCP did not differ (p = 0.065). FAZ area was numerically larger in vitamin-D-insufficient eyes but was not statistically different (p = 0.168). Functionally, retinal sensitivity decline was greater in vitamin-D-insufficient eyes (−2.89 ± 1.29 dB vs. −2.16 ± 1.04 dB; p = 0.003), and mean central sensitivity was lower (p = 0.010), whereas contrast sensitivity did not differ between groups. Serum vitamin D levels < 30 ng/mL are associated with early, subclinical, structural and microvascular retinal alterations in healthy adults, supporting a potential role of hypovitaminosis D as a modifier of retinal integrity
Thin HPFRC Jackets for Axially Loaded RC Columns: Mechanical Behavior and Efficacy of Strengthening
No full textThe environmental impact of the construction sector underscores the urgent need for sustainable solutions to extend the service life of existing structures. This study explores High-Performance Fiber-Reinforced Concrete (HPFRC) for strengthening reinforced-concrete (RC) columns subjected to axial compression. Twelve RC columns were tested, each 1200 mm high and with varying cross-sectional shapes (circular, square, and rectangular). Strengthening was achieved using thin HPFRC jackets (less than 30 mm thick), applied without additional internal reinforcement and following simple surface preparation techniques such as sandblasting. Full-height jacketing significantly improved axial load capacity. Its effectiveness did not decrease with the shape of the cross-section, with square columns showing up to a 105% increase and rectangular ones up to 87%, compared to unstrengthened columns with the same concrete strength. The highest improvement was observed in the square column with full-height jacketing and the most significant geometric strengthening ratio (52.6%), which doubled its axial capacity. This ratio was directly related to performance gains. Although ductility gains were limited, the full-jacketed specimens did not fail explosively: their failure mode was progressive, providing a useful warning before collapse. HPFRC jacketing can be especially effective for non-circular columns, outperforming FRP jacketing and eliminating the need for additional protective layers against impact or fire
Hypersexual Behavior Inventory for Men Who Have Sex with Men: Bifactor Validation, IRT Diagnostics, and Clinical Cutoffs
No full textBackground: Compulsive Sexual Behavior Disorder is highly prevalent among men who have sex with men (MSM) and is associated with adverse health outcomes, yet validated assessment tools for this population are critically lacking. This research aimed to adapt the Hypersexual Behavior Inventory (HBI) among Portuguese MSM (N = 1116 across four studies). Method and Results: Following translation and adaptation (Study 1a/1b), Exploratory Factor Analysis suggested a two-factor structure of the instrument (Study 2). Moreover, Item Response Theory showed strong item discrimination and convergent/divergent validity. Confirmatory Factor Analysis (Study 3) favored a bifactor structure—one general hypersexuality factor plus two facets (Control/Consequences and Coping). Criterion validity was evident from positive associations with depression, anxiety, and stress. Finally, ROC analyses (Study 4) demonstrated excellent discrimination and established clinical cutoffs. Conclusions: Overall, the HBI emerges as a reliable, culturally attuned tool for early risk identification in MSM and for informing tailored psychosocial interventions in health settings
Tin–Lead Liquid Metal Alloy Source for Focused Ion Beams
No full textFocused Ion Beam (FIB) systems are increasingly utilized in nanotechnology for nanostructuring, surface modification, doping, and rapid prototyping. Recently, their potential for quantum applications has been explored, leveraging FIB’s direct-write capabilities for in situ single ion implantation, which is crucial for fabricating single photon emitters. Color centers in diamond can function as qubits and are of particular interest due to their capacity to store and transmit quantum information. While Group-IV color centers exhibit high brightness, they require low temperatures to retain coherence. However, lead-vacancy in diamond (PbV) operates at the higher end (4 K) of this temperature spectrum due to larger ground-state splitting, making them particularly interesting. In this context, our study presents results for lead (Pb)-containing alloys with eutectic points below 600 °C and results on using tantalum (Ta) and titanium (Ti) as emitter materials for a Pb liquid metal alloy ion source. We show that a standard FIB system is able to resolve the different Pb isotopes and achieve nanoscale spot sizes, as required for quantum information science applications
Spatial Prediction of Forest Fire Risk in Guangdong Province Using Multi-Source Geospatial Data and Sparrow Search Algorithm-Optimized XGBoost
No full textForest fires pose escalating threats to ecological security and public safety in Guangdong Province. This study presents a novel machine learning framework for fire occurrence prediction by synergistically integrating multi-source geospatial data. Utilizing Moderate-resolution Imaging Spectroradiometer (MODIS) active fire detections from 2014 to 2023, we quantified historical fire patterns and incorporated four categories of predisposing factors: meteorological variables, topographic attributes, vegetation characteristics, and anthropogenic activities. Spatiotemporal clustering dynamics were characterized via kernel density estimation and spatial autocorrelation analysis. An XGBoost classifier, hyperparameter-optimized through the Sparrow Search Algorithm (SSA), achieved a predictive accuracy of 90.4%, with performance evaluated through precision, recall, and F1-score. Risk zoning maps generated from predicted probabilities were validated against independent fire records from 2019 to 2024. Results reveal pronounced spatial heterogeneity, with high-risk zones concentrated in northern and western mountainous areas, constituting 29% of the provincial territory. Critical driving factors include slope gradient, proximity to roads and rivers, temperature, population density, and elevation. This robust predictive framework furnishes a scientific foundation for spatially-explicit fire prevention strategies and optimized resource allocation in key high-risk jurisdictions, notably Qingyuan, Shaoguan, Zhanjiang, and Zhaoqing
Going Green in SMEs: Unpacking How Innovative Work Behavior Impacts Employee Commitment Through a Mediated–Moderated Model
No full textPrevious studies on innovative work behavior (GIWB) have mainly focused on exploring its favorable sustainable consequences and its unseen potential harmful outcomes. To address this gap, this study sought to explore the associations between GIWB and perceived greenwashing, work exhaustion, and environmental commitment among hotel employees. It also assessed managerial support as an alleviator of these negative outcomes. To that end, this research conducted a quantitative approach and used a self-reported questionnaire survey among employees and supervisors in green hotels. Based on valid replies from 419 participants from Small- and Medium-Sized Hotels (SMSH), we conduct Structural Equation Modelling (SEM) with Smart PLS 4.0. The results revealed that GIWB exerted positive effects on employees perceived greenwashing, green work exhaustion, and environmental commitment. The results also underscored the salient role of management support in alleviating the negative effects of GIWB on these outcomes’ perceived greenwashing and green work exhaustion. This study addressed a notable gap in knowledge and provides some valuable suggestions to avert the paradoxical effects of GIWB, leading to better organizational sustainable performance
A 10-Year Study on Percutaneous Cholecystostomy for Acute Cholecystitis at a Tertiary Referral Hospital
No full textBackground: Percutaneous cholecystostomy (PC) is an effective, minimally invasive treatment for patients with acute cholecystitis (AC) who are at high surgical risk and may be used as a bridge to surgery in critically ill patients. This study aimed to evaluate the safety of PC in patients with AC over a 10-year period. Methods: Patients who underwent PC for AC at our institution between January 2013 and May 2023 were included. Patients were categorised into the definitive and bridging PC groups. Clinical characteristics, procedure-related complications, recurrence, and overall survival were analysed. Statistical analyses were used to identify in-hospital mortality-related risk factors. Results: A total of 449 patients were included, and 89.5% had an ASA score ≥ 3. The median time to PC was 1 day, and 17.6% of patients required ICU admission. Drainage tube-related complications occurred in 37 (8.2%) patients. The median drainage and hospital stay durations were 9 (IQR 6–14) and 12 (IQR 9–15) days, respectively. During follow-up, recurrent AC was observed in 34 (7.6%), with a median time to recurrence of 63 (IQR 29–312) days. PC was the definitive treatment in 275 (61.2%) patients. The overall mortality rate was 5.3% (n = 24), with no deaths related to the drainage procedure. Sepsis on admission was an independent risk factor related to in-hospital mortality. Conclusions: Our findings confirmed that PC is a safe and effective treatment alternative for managing AC in high-risk patients with low complication and mortality rates
Improving Energy Efficiency and Reliability of Parallel Pump Systems Using Hybrid PSO–ADMM–LQR
No full textThis paper proposes a hybrid optimization–control framework that combines the Particle Swarm Optimization (PSO) algorithm, the Alternating Direction Method of Multipliers (ADMM), and a Linear–Quadratic Regulator (LQR) for energy-efficient and reliable operation of parallel pump systems. The PSO layer performs global exploration over mixed discrete–continuous design variables, while the ADMM layer coordinates distributed flows under head and reliability constraints, yielding hydraulically feasible operating points. The inner LQR controller achieves optimal speed tracking with guaranteed asymptotic stability and improved robustness against nonlinear load disturbances. The overall PSO–ADMM–LQR co-design minimizes a composite objective that accounts for steady-state efficiency, transient performance, and control effort. Simulation results on benchmark multi-pump systems demonstrate that the proposed framework outperforms conventional PSO- and PID-based methods in terms of energy savings, dynamic response, and robustness. The method exhibits low computational complexity, scalability to large systems, and practical suitability for real-time implementation in smart water distribution and industrial pumping applications
Entrepreneurial Dynamics: The Serial Role of Entrepreneurial Alertness and Intention in the Impact of Individual Entrepreneurial Orientation on Behavior in an Emerging Economy
No full textBuilding on multiple theoretical views, this paper aimed to investigate how traits and their specific mechanisms transfer into realized entrepreneurial behaviors. Thus, this paper seeks to address various apparent gaps through an integrative theoretical framework that examines the serial mediation between Individual Entrepreneurial Orientation, Entrepreneurial Alertness, and Entrepreneurial Intentions, and their influence on Entrepreneurial Behavior. Based on a quantitative method with a survey strategy, this paper applied partial least squares-based structural equation modeling on a sample of 405 aspiring entrepreneurs in Saudi Arabia. The paper’s findings confirmed the positive and significant relationships between Individual Entrepreneurial Orientation and Entrepreneurial Alertness, Entrepreneurial Alertness and Entrepreneurial Intentions, and Entrepreneurial Intentions and Entrepreneurial Behavior. In addition, the results supported three indirect hypotheses, corroborating that Individual Entrepreneurial Orientation could affect Entrepreneurial Behavior indirectly through Entrepreneurial Alertness and Entrepreneurial Intentions. Likewise, the results supported the serial mediation hypothesis, in which Individual Entrepreneurial Orientation influenced Entrepreneurial Behavior through a sequential process, with both Entrepreneurial Alertness and Entrepreneurial Intentions as mediators. This paper offers theoretical and practical implications for the literature and practice of entrepreneurship. The study contributes to our understanding of the traits and cognitions that can motivate individuals to start a business. In addition, this study responded to many previous calls to examine not only the direct effects of EI antecedents but also the mediating roles of key factors
Discrimination and Symptoms of Post-Traumatic Stress Among Black Transgender Women in the United States: The Moderating Effect of Sleep
No full textBackground: Black transgender women experience high rates of intersectional discrimination contributing to post-traumatic stress disorder (PTSD) symptoms. While sleep typically buffers psychological distress among general populations, these relationships remain underexplored among Black transgender women, and existing protective sleep literature derives primarily from non-Hispanic White, cisgender, socioeconomically advantaged populations. Methods: This exploratory secondary cross-sectional analysis of 155 Black transgender women (aged 18+) examined whether sleep quality (Pittsburgh Sleep Quality Index) moderates associations between discrimination (Intersectional Discrimination Index) and PTSD symptoms (PTSD Symptom Checklist-DSM-5) using moderated multiple linear regression models, controlling for age (n = 139–149). Results: Contrary to expectations, better sleep quality strengthened associations between day-to-day (p = 0.0126) and major discrimination (p = 0.0235) and the PTSD symptom severity. Conclusions: These exploratory findings reveal paradoxical sleep-distress relationships among Black transgender women that contradict patterns documented among general populations, highlighting critical limitations in applying existing psychological frameworks to multiple marginalized communities. Results underscore urgent needs for culturally validated assessment instruments and comprehensive measurement of structural determinants (housing stability, economic security, and neighborhood safety) before concluding psychology in populations experiencing intersectional oppressions