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Background: Undergraduate nursing students (UNSs) often enter clinical training just as they are still mastering the emotional labor of the profession. In Nepal, where teaching hierarchies discourage upward dialogue and hospitals routinely struggle with overcrowding, supply shortages, and outward nurse migration, these learners confront a distinct, under-documented burden of psychological distress. Objective: This study examines how UNSs interpret, negotiate, and cope with the mental health challenges that arise at the intersection of cultural deference, resource scarcity, and migration-fueled uncertainty. Methods: A qualitative design employing reflexive thematic analysis (RTA), guided by the Reflexive Thematic Analysis Reporting Guidelines (RTARG), was used. Fifteen second-, third-, and fourth-year Bachelor of Science in Nursing students at a major urban tertiary institution in Nepal were purposively recruited via on-campus digital flyers and brief in-class announcements that directed students (by QR code) to a secure sign-up form. Participants then completed semi-structured interviews; audio files were transcribed verbatim and iteratively analyzed through an inductive, reflexive coding process to ensure methodological rigor. Results: Four themes portray a continuum from silenced struggle to systemic constraint. First, Shrouded Voices, Quiet Connections captures how students confide only in trusted peers, fearing that formal disclosure could be perceived as weakness or incompetence. Second, Performing Resilience: Masking Authentic Struggles describes the institutional narratives of “strong nurses” that drive students to suppress anxiety, adopting scripted positivity to satisfy assessment expectations. Third, Power, Hierarchy, and the Weight of Tradition reveals that strict authority gradients inhibit questions in classrooms and clinical placements, leaving stress unvoiced and unaddressed. Finally, Overshadowed by Systemic Realities shows how chronic understaffing, equipment shortages, and patient poverty compel students to prioritize patients’ hardships, normalizing self-neglect. Conclusions: Psychological distress among Nepalese UNSs is not an individual failing but a product of structural silence and resource poverty. Educators and policymakers must move beyond resilience-only rhetoric toward concrete reforms that dismantle punitive hierarchies, create confidential support avenues, and embed collaborative pedagogy. Institutional accountability—through regulated workloads, faculty-endorsed wellbeing forums, and systematic mentoring—can shift mental health care from a private struggle to a shared professional responsibility. Multi-site studies across low- and middle-income countries are now essential for testing such system-level interventions and building a globally resilient, compassionate nursing workforce. Full article

Building-integrated photovoltaics (BIPV) is expected to play a relevant role in decarbonising our cities, both in new buildings and retrofit projects, making them more sustainable, resilient and pleasant. However, BIPV remains a niche market. To understand the reasons and help boost its development, this paper provides insights into BIPV through a holistic and systematic analysis that considers BIPV’s dual nature as both photovoltaic and building product. The methodology is based on the analyses of several BIPV technological innovation systems (TISs) developed in six countries, as well as extensive comparative assessments and investigations to identify key global features of BIPV. Social aspects, market status and forecast, perspectives from the photovoltaic and building sectors, and related regulations and standardisation are key aspects analysed to develop recommendations for policymakers. Outcome examples are low to moderate acceptance of BIPV among building owners, who give cost reasons for choosing building-added photovoltaics (BAPV) over BIPV, as well as a need for information, official guidance, skilled personnel, improved cross-sector collaboration, availability of BIPV products, proper digital tools and specific regulation to improve BIPV’s legitimacy in the construction sector. Essential is developing policies that encourage the adoption of BIPV, including standardisation, promotion and financing. Full article

Fire retardancy and thermal management are critical for energy-efficient, fire-safe buildings. Natural wood, a mainstream construction material, possesses inherent advantages but lacks such dual functionality. Silicified wood was fabricated via multi-cycle silicification of native wood, where SiO₂ uniformly infiltrates and fills the lumens. The treated wood material displays an improved limiting oxygen index (LOI) from 21.9% to 36.0%, and delayed ignition from 15 s to 50 s, compared to untreated wood. It demonstrates a low thermal conductivity of 0.074 W·m⁻¹·K⁻¹, showing enhanced emissivity. When heated on a 75 °C hot plate, the silicified wood surface reaches ~50 °C after 5 s, versus ~60 °C for native wood. These enhancements collectively improve thermal management performance, achieving insulation through reduced thermal conduction and passive cooling via optimized infrared regulation. Ultimate tensile stress remains nearly unchanged post-treatment, while toughness is significantly improved. This work advances wood as a sustainable building material, with promising potential for fire-safe, energy-efficient construction applications. Full article

This paper introduces a new optimization problem-solving method based on how the stingless bee Tetragonula carbonaria builds and regulates temperature in the hive. The Tetragonula carbonaria Optimization Algorithm (TGCOA) models three different behaviors: strengthening the structure’s hive when it is cold, building combs in a spiral pattern at medium temperatures, and stabilizing the hive when it is hot. These temperature-dependent strategies dynamically balance global exploitation and local exploration within the solution space, enabling a more efficient search. To validate the efficiency and effectiveness of the proposed method, the TGCOA algorithm was tested using ten unimodal and ten multimodal benchmark functions, twenty-eight constrained problems with dimensions set to 10, 30, 50, and 100 taken from the IEEE CEC 2017, and seven real-world engineering design challenges. Furthermore, it was compared with ten algorithms from the literature. Wilcoxon signed-rank and Friedman statistical tests were performed to assess the outcomes. The results on the benchmark problems showed that the approach outperformed 80% of the algorithms at a 5% significance level in the Wilcoxon signed-rank test and ranked first overall according to the Friedman test. Additionally, in multidimensional problems, the TGCOA was ranked first in dimensions 30, 50, and 100. Moreover, in engineering problems, the approach demonstrated a high capacity to solve constraint problems, obtaining better results than the algorithms that were compared. Full article

Wind-induced erosion and extreme weather events pose growing risks to the structural integrity of masonry heritage buildings. However, current mitigation approaches often overlook ecological sustainability. This study investigates the wind-regulating effects of vegetation surrounding the Zhen Guo Tower, a 400-year-old masonry structure in Weihui, Henan Province, China. Using computational fluid dynamics (CFD) simulations, we first assess the protective performance of the existing vegetation layout and then develop and evaluate an optimized plant configuration. The results show that the proposed multilayered vegetation arrangement effectively reduces wind speeds by up to 13.57 m/s under extreme wind conditions, particularly within the 5–15 m height range. Wind protection efficiency improved by 28–68% compared to the baseline. This study demonstrates a replicable and ecologically integrated strategy for mitigating wind hazards in masonry heritage sites through vegetation-based interventions. Full article

This study evaluates the energy performance and efficiency of a low-concentration photovoltaic (CPV) system integrated with a phase change material (PCM), referred to as the CPV–PCM system, which stores and delivers thermal energy for building applications. A paraffin-based PCM with a melting point range of 58–60 °C was selected to align with typical building temperature requirements. The system was tested over three consecutive days in July at Al Ain, United Arab Emirates, under extreme climatic conditions (2100 W/m² solar irradiance, 35–45 °C ambient temperature), and its performance was compared to standard CPV and traditional tracked PV systems. The results demonstrate that PCM integration significantly enhances thermal regulation, reducing CPV peak temperatures by 38 °C (from 123 °C to 85 °C) and average temperatures by 22 °C (from 88 °C to 66 °C). The CPV–PCM system achieved a total energy efficiency of 60%, doubling that of standard CPV (30%) and tracked PV (25%), with cumulative electrical and thermal energy outputs of 370 Wh and 290 Wh, respectively. This dual electrical–thermal output enables the system to meet building heating demands, such as ~200–300 Wh/m² for domestic hot water and ~100–150 Wh/m² for space heating in United Arab Emirates winters, positioning it as a sustainable solution for energy-efficient buildings in arid regions. The findings underscore the advantages of PCM-based thermal control in CPV systems for hot climates, addressing gaps in prior studies focused on moderate conditions. Future research should explore long-term durability, optimized containment techniques, and alternative PCMs to further improve performance. Full article

Drawing on in-depth interviews and thematic analysis, this study explores the therapeutic benefits of outdoor experiences through the lived experiences of 24 outdoor practitioners, including educators, environmentalists, therapists, and program leaders. Three core themes emerged: (a) nature as an emotional regulator and reflective space; (b) therapeutic benefits of human–nature relationships; and (c) decolonial, bioregional, and cultural healing. Although practitioners facilitated physical challenges and skill-building for their participants, they primarily described outdoor experiences as relational, somatic, and culturally rooted practices that foster emotional regulation, grief processing, identity integration, and social inclusion. Healing emerged through solitude, silence, ancestral connections, sacred landscapes, inclusive dynamics, and the restoration of cultural knowledge. This study’s results challenge Western-centric outdoor education models by foregrounding Indigenous and postcolonial perspectives embedded in Indian ecological traditions. The results contribute to global discussions on decolonizing outdoor fields and offer implications for culturally responsive, emotionally safe, and ecologically grounded practices. Full article

Coral reefs are increasingly threatened by global climate change, and mass bleaching and mortality events caused by elevated seawater temperature have led to coral loss worldwide. Hainan Island hosts extensive coral reef ecosystems in China, yet seasonal variation in Symbiodiniaceae communities within this region remains insufficiently understood. We aimed to investigate the temperature-driven adaptability regulation of the symbiotic Symbiodiniaceae community in reef-building corals, focusing on the environmental adaptive changes in its community structure in coral reefs between cold (23.6–24.6 °C) and warm (28.2–30.6 °C) months. Symbiodiniaceae shuffling and rare genotype turnover were discovered in adaptability variations in the symbiotic Symbiodiniaceae community between two months. Symbiodiniaceae genetic diversity increased during warm months, primarily due to temporal turnover of rare genotypes within the Cladocopium and Durusdinium genera. Coral Favites, Galaxea, and Porites exhibited the shuffling of Symbiodiniaceae between tolerant Durusdinium and sensitive Cladocopium. Symbiodiniaceae interactions in G. fascicularis and P. lutea exhibited the highest levels of stability with the increase in temperature, whereas the interactions in A. digitifera and P. damicornis showed the lowest levels of stability. Rare genotypes functioned as central hubs and important roles within Symbiodiniaceae communities, exhibiting minimal responsiveness to temperature fluctuations while maintaining community structural stability. The temperature-driven adaptability regulation of symbiotic Symbiodiniaceae could be achieved by Symbiodiniaceae shuffling and rare genotype turnover. The process might be aggravated by concurrent adverse factors, including elevated salinity, pollution, and anthropogenic disturbance. These findings provide insights into how the Symbiodiniaceae community influences the adaptation and resilience of coral hosts to temperature fluctuations in coral reefs. Furthermore, they may contribute to assessing the reef-building coral’s capacity to withstand environmental stressors associated with global climate change. Full article

Integrating renewable energy, particularly wind power, into modern power systems introduces challenges concerning stability and reliability. These issues require enhanced regulation to balance power supply with load demand. Flexible loads and energy storage provide viable solutions to stabilize the grid without relying on new resources. This paper proposes building thermostatically controlled loads (BTLs), such as heating, ventilation, and air conditioning (HVAC) systems, as flexible demand-side management tools to address the challenges of intermittent energy sources. A new concept is introduced, portraying BTLs as a stochastic battery with losses, offering a compact representation of their dynamics. BTLs’ thermal characteristics, user-defined set points, and ambient temperature changes determine the power limits and energy capacity of this stochastic battery. The model is simulated using DIgSILENT Power Factory, which includes thermal power plants, gas turbines, wind power plants, and BTLs. A dynamic dispatch strategy optimizes power generation while utilizing BTLs to balance grid fluctuations caused by variable wind energy. Performance analysis shows that integrating BTLs with conventional thermal plants can reduce variability and improve grid stability. The study highlights the dual role of simulating overall flexibility and applying dynamic dispatch strategies to enhance power systems with high renewable energy integration. Full article

Vegetation plays an important role in the hydrological cycle, carbon storage and regional climate. It provides multiple ecosystem services, regulates ecosystem structure and promotes the sustainable and stable development of the earth’s ecosystem. Under the interference of the ever-changing environment, vegetation vulnerability is increasingly evident. This study focuses on Yunnan Province, China, where we analyze the spatiotemporal dynamics of NDVI at both provincial and municipal scales. Utilizing methods such as geographical detectors, time-lag analysis, and residual analysis, we identify key drivers of NDVI changes in Yunnan. From 2001 to 2023, the multi-year average NDVI in Yunnan decreases spatially from southwest to southeast, with the annual maximum NDVI increasing at a rate of 0.025 per decade. Qujing City exhibits the fastest NDVI growth, while Diqing City shows the slowest. Vegetation degradation is primarily concentrated in central Yunnan. The NDVI in Yunnan demonstrates significant spatial heterogeneity, influenced by a combination of climatic, topographic, and anthropogenic factors. The interaction between land use type and precipitation is identified as a key driver, explaining over 50% of the spatial distribution of NDVI. Approximately 83% and 82% of vegetated areas in Yunnan exhibit delayed responses to precipitation and temperature changes, respectively. Notably, 73% of the NDVI increase and 7% of the NDVI decrease in Yunnan were jointly affected by climate change and human activities, and positive contributions from these factors cover 92% and 90% of the area, respectively. The impact of human activities on vegetation is mainly positive, although urbanization in central Yunnan significantly inhibits NDVI. By elucidating key mechanisms, this work fosters balanced vegetation–environment synergies in Yunnan and supports the building of ecological safeguards in China. Full article

The intensification of urban heat in high-density cities has raised growing concerns for public health, infrastructural resilience, and environmental sustainability. As large-scale, multi-functional open spaces, sports stadiums play an underexplored role in shaping urban thermal patterns. This study investigates the spatial and temporal thermal characteristics of eight representative stadiums in central Shanghai and the Pudong New Area from 2018 to 2023. A dual-framework approach is proposed: the Stadium-based Urban Island Regulation (SUIR) model conceptualizes stadiums as active cooling agents across micro to macro spatial scales, while the Multi-source Thermal Cognition System (MTCS) integrates multi-sensor satellite data—Landsat, MODIS, Sentinel-1/2—with anthropogenic and ecological indicators to diagnose surface temperature dynamics. Remote sensing fusion and machine learning analyses reveal clear intra-stadium thermal heterogeneity: track zones consistently recorded the highest land surface temperatures (up to 37.5 °C), while grass fields exhibited strong cooling effects (as low as 29.8 °C). Buffer analysis shows that cooling effects were most pronounced within 300–500 m, varying with local morphology. A spatial diffusion model further demonstrates that stadiums with large, vegetated buffers or proximity to water bodies exert a broader regional cooling influence. Correlation and Random Forest regression analyses identify the building volume (r = 0.81), NDVI (r = −0.53), nighttime light intensity, and traffic density as key thermal drivers. These findings offer new insight into the role of stadiums in urban heat mitigation and provide practical implications for scale-sensitive, climate-adaptive urban planning strategies. Full article

This review focuses on the advancements of CO₂ transcritical cycle technology in building indoor environmental regulation, particularly in combined heating and cooling applications. The paper highlights the energy efficiency and environmental benefits of CO₂ as a natural refrigerant, which has zero ozone depletion potential (ODP) and very low global warming potential (GWP). It provides a comprehensive overview of recent optimization strategies, including distributed compression, the integration of ejectors and expanders, and the design improvements of key components such as gas coolers, compressors, and throttling valves. Through optimization strategies such as dual-system cycles, this technology can achieve a COP improvement of 15.3–46.96% in heating scenarios; meanwhile, with the help of distributed compression technology, its cooling capacity can be enhanced by up to 26.5%. The review also examines various operating conditions such as discharge pressure and subcooling, which significantly affect system performance. The paper concludes by identifying the current challenges in the application of CO₂ systems, such as high initial costs and system stability under extreme conditions, and suggests future research directions to overcome these limitations and improve the practical application of CO₂ transcritical cycles in the building industry. Overall, it is concluded that the development of expander-compressors holds great potential for achieving better performance and represents a promising direction for future advancements in this field. Full article

As large language model (LLM) tutors evolve from scripted helpers into adaptive educational partners, their capacity for self-regulation, ethical decision-making, and internal monitoring will become increasingly critical. This paper introduces the Needs-Driven Consciousness Framework (NDCF) as a novel, integrative architecture that combines Dennett’s multiple drafts model, Damasio’s somatic marker hypothesis, and Tulving’s tripartite memory system into a unified motivational design for synthetic consciousness. The NDCF defines three core regulators, specifically Survive (system stability and safety), Thrive (autonomy, competence, relatedness), and Excel (creativity, ethical reasoning, long-term purpose). In addition, there is a proposed supervisory Protect layer that detects value drift and overrides unsafe behaviours. The core regulators compute internal need satisfaction states and urgency gradients, feeding into a softmax-based control system for context-sensitive action selection. The framework proposes measurable internal signals (e.g., utility gradients, conflict intensity Ω), behavioural signatures (e.g., metacognitive prompts, pedagogical shifts), and three falsifiable predictions for educational AI testbeds. By embedding these layered needs directly into AI governance, the NDCF offers (i) a psychologically and biologically grounded model of emergent machine consciousness, (ii) a practical approach to building empathetic, self-regulating AI tutors, and (iii) a testable platform for comparing competing consciousness theories through implementation. Ultimately, the NDCF provides a path toward the development of AI tutors that are capable of transparent reasoning, dynamic adaptation, and meaningful human-like relationships, while maintaining safety, ethical coherence, and long-term alignment with human well-being. Full article

The increasing demand for high-performance power converters for electric vehicle (EV) applications places a significant emphasis on developing effective and robust control strategies for DC-DC converter operation. This paper deals with the development, simulation, and experimental validation of an adaptive Lyapunov-type Nonlinear Sliding Mode Control (L-SMC) strategy for a DC–DC boost converter, addressing significant uncertainties caused by large variations in system parameters (R and L) and ensuring the tracking of a voltage reference. The proposed control strategy employs the Lyapunov stability theory to build an adaptive law to update the parameters of the sliding surface so the system can achieve global asymptotic stability in the presence of uncertainty in inductance, capacitance, load resistance, and input voltage. The nonlinear sliding manifold is also considered, which contributes to a more robust and faster convergence in the controller. In addition, a logic optimization technique was implemented that minimizes switching (chattering) operations significantly, and as a result of this, increases ease of implementation. The proposed L-SMC is validated through both simulation and experimental tests under various conditions, including abrupt increases in input voltage and load disturbances. Simulation results demonstrate that, whether under nominal parameters (R = 320 Ω, L = 2.7 mH) or with parameter variations, the voltage overshoot in all cases remains below 0.5%, while the steady-state error stays under 0.4 V except during the startup, which is a transitional phase lasting a very short time. The current responds smoothly to voltage reference and parameter variations, with very insignificant chattering and overshoot. The current remains stable and constant, with a noticeable presence of a peak with each change in the reference voltage, accompanied by relatively small chattering. The simulation and experimental results demonstrate that adaptive L-SMC achieves accurate voltage regulation, a rapid transient response, and reduces chattering, and the simulation and experimental testing show that the proposed controller has a significantly lower steady-state error, which ensures precise and stable voltage regulation with time. Additionally, the system converges faster for the proposed controller at conversion and is stabilized quickly to the adaptation reference state after the drastic and dynamic change in either the input voltage or load, thus minimizing the settling time. The proposed control approach also contributes to saving energy for the application at hand, all in consideration of minimizing losses. Full article

The global transition toward renewable energy and the electrification of transportation is imposing unprecedented power quality (PQ) challenges on modern distribution networks, rendering traditional governance models inadequate. To bridge the existing research gap of the lack of a holistic analytical framework, this review first establishes a systematic diagnostic methodology by introducing the “Triadic Governance Objectives–Scenario Matrix (TGO-SM),” which maps core objectives—harmonic suppression, voltage regulation, and three-phase balancing—against the distinct demands of high-penetration photovoltaic (PV), electric vehicle (EV) charging, and energy storage scenarios. Building upon this problem identification framework, the paper then provides a comprehensive review of advanced mitigation technologies, analyzing the performance and application of key ‘unit operations’ such as static synchronous compensators (STATCOMs), solid-state transformers (SSTs), grid-forming (GFM) inverters, and unified power quality conditioners (UPQCs). Subsequently, the review deconstructs the multi-timescale control conflicts inherent in these systems and proposes the forward-looking paradigm of “Distributed Dynamic Collaborative Governance (DDCG).” This future architecture envisions a fully autonomous grid, integrating edge intelligence, digital twins, and blockchain to shift from reactive compensation to predictive governance. Through this structured approach, the research provides a coherent strategy and a crucial theoretical roadmap for navigating the complexities of modern distribution grids and advancing toward a resilient and autonomous future. Full article