Search Results (5,182)

Understanding the elevation-dependent response of mountain snow cover to climate change requires transcending statistical correlations to reveal the underlying physical mechanisms. This study investigates these mechanisms in the Upper Yarkand River Basin (U-YRB, located on the northwestern edge of the Qinghai–Tibet Plateau) from 2002 to 2020 by integrating a Gradient-Boosted Decision Tree (GBDT) model, a process-based degree-day model, and Structural Equation Modeling (SEM). Our analysis reveals a significant overall decline in Snow Cover Area (SCA) at a rate of −0.25%·a⁻¹, with the rate of decrease accelerating below 4000 m but slowing above this threshold. Snow Depth (SD) exhibited a distinct elevation-dependent trend, decreasing at elevations below 3500 m while increasing above 4000 m. GBDT analysis quantified the shifting dominance of climatic drivers: temperature was the primary factor reducing SCA across all elevations, though its contribution diminished with increasing elevation. Precipitation played a critical yet contrasting role, emerging as the key positive driver for SD accumulation at high elevations (>4500 m). A comparative analysis of snowfall and snowmelt processes identified snowmelt as the key process governing elevation-dependent patterns, peaking around 4000 m. Crucially, SEM elucidated a mechanistic shift across the 4000 m threshold: below 4000 m, snow cover loss was primarily driven by temperature via its strong positive effect on snowmelt. Above 4000 m, while the influence of temperature persisted, the dominant positive effect of precipitation on snowfall became the key driver of the observed SD increase. This shift signals a fundamental transition from melt-dominated dynamics at lower elevations to accumulation-influenced dynamics at higher elevations. Our findings clarify the physical processes behind elevation-dependent snow cover changes and underscore the necessity of elevation-stratified frameworks for hydrological prediction and water resource management in alpine basins. Full article

Background: Despite advances in monitoring and forecasting systems, natural disasters continue to cause significant human losses. During the response phase, fast decisions are required to allocate limited resources, particularly rescue helicopters, which play a key role in reaching inaccessible areas. However, helicopter allocation involves trade-offs between efficiency and operational safety under uncertain conditions. Methods: This study proposes a decision-support methodology based on Multi-Criteria Decision Analysis (MCDA) for allocating rescue helicopters during disaster response. The approach integrates Value-Focused Thinking (VFT) and Multi-Attribute Value Theory (MAVT) to structure objectives, assign weights, and evaluate alternatives using criteria related to mission safety, response time, and expected number of rescued victims. The method is illustrated through a simulated flood response scenario in a Brazilian regional context. Results: The results show that the model allows decision-makers to compare allocation scenarios and to make explicit the trade-offs between operational efficiency and safety. The application indicates that small reductions in efficiency may lead to relevant gains in operational safety, particularly under adverse weather conditions. Conclusions: The proposed approach provides a transparent and traceable structure for supporting helicopter allocation decisions during disaster response. It contributes to more consistent decision-making in critical operations, especially in contexts characterized by uncertainty and time pressure. Full article

The civil Global Navigation Satellite System (GNSS) signal is broadcast with an open structure, making it vulnerable to spoofing attacks. Incorporating authentication data into GNSS signals is a significant measure to enhance system security. Precise Point Positioning (PPP) technology has garnered extensive attention for its ability to provide real-time services with centimeter-level accuracy. The PPP service features a high data update rate, with the validity period of the data being approximately ten to twenty seconds. This imposes more stringent requirements on the authentication data rate and the authentication time. Code Shift Keying (CSK) technology has emerged as a key candidate for satellite-based PPP signal design, as it can increase the data rate without requiring additional spectrum resources. This paper investigates authentication methods for CSK-modulated satellite-based PPP signals. Two approaches are proposed: phase modulation authentication and polarity modulation authentication. Simulation and analysis results indicate that the PPP signal with phase modulation authentication experiences less carrier-to-noise ratio (C/N₀) loss and has a higher detection probability. In contrast, the signal with polarity modulation authentication does not suffer from C/N₀ loss and achieves a higher data rate and a shorter authentication time. These findings can serve as valuable references for future GNSS signal design. Full article

The Military Macaw is a Neotropical psittacid that is endangered in Mexico. It faces significant threats due to habitat loss and the illegal pet trade. However, little is known about the nutritional characteristics of the plant resources available to this species throughout its annual cycle. This study aimed to characterize the nutritional profile of the fruits consumed by macaws in the Alto Balsas Basin, Mexico, and to infer potential seasonal patterns in the availability of the fruits they feed on in relation to the Macaws’ reproductive phenology. We identified 13 plant species that have been consistently reported as components of the diet of the macaws within the Alto Balsas Basin using a literature review, field observations, and local interviews. We conducted bromatological analyses to assess the content of moisture, protein, lipids, carbohydrates, and fiber for the pulp and seeds of all 13 identified plant species. Although we did not measure quantitative food intake, we integrated these data with reproductive phenology and resource availability to infer potential patterns of nutritional use. The results revealed significant differences in nutritional content among the different species, as well as seasonal variation in the nutritional profiles of available resources that coincide with the physiological demands of the macaw life cycle. During the non-breeding season, the availability of species whose fruits have high lipid and carbohydrate contents, such as Bursera spp., hackberry and madras thorn, may provide essential energy. Conversely, during the breeding season, resources with higher lipid and protein content (such as Mexican kapok tree and red mombin) could support the increased energetic investment associated with courtship, egg production, and chick provisioning. Although our study did not directly quantify the amount of each food item consumed, the integration of nutritional and ecological data provides a preliminary view of how resource quality may influence seasonal foraging patterns, offering valuable insights for the conservation and management of this species. Full article

This article analyzes prohibitions against the destruction of flora in the calendrical regulations of the late Western Han period and in the millenarian cosmological discourses in the Taiping jing 太平經 (Canon of Great Peace). The study focuses on the “Zhaoshu sishi yueling wushi tiao” 詔書四時月令五十條 (“Edict of Monthly Ordinances for the Four Seasons in Fifty Articles”) which was promulgated by Wang Mang in 5 CE. The Edict prohibited setting fire to forests and was intended to restore cosmic harmony. At the time, natural disasters and celestial anomalies were interpreted as signs of the loss of the Mandate of Heaven. Heavenly patterns and hemerology play a central role here by enabling environmental regulations to be incorporated into a political logic of legitimization. The Canon of Great Peace reinterprets these norms by replacing seasonal cycles with an interpretation of balance between yin and yang and by giving environmental prohibitions eschatological significance. Thus, calendrical regulations for natural resource management transform into an apocalyptic discourse in which the natural environment becomes the setting for cosmic disorder that must be avoided. Full article

Grounded in the Conservation of Resources (COR) theory, this study investigates the impact of workplace bullying on the psychological and physical well-being of Information Technology (IT) professionals in five major metropolitan cities in India (Chennai, Bengaluru, Hyderabad, Pune, and Mumbai). Specifically, it examines how workplace bullying increases psychological distress and how this distress subsequently impairs sleep quality, along with the moderating role of resilience in this relationship. Data were collected from 380 Information Technology employees using a structured online questionnaire through a Stratified simple random sampling technique. The sample consisted of full-time IT professionals across various age groups, job levels, and work arrangements. The hypothesized relationships were tested using Partial Least Squares Structural Equation Modeling (PLS-SEM). Results show that workplace bullying significantly elevates psychological distress and reduces sleep quality. Psychological distress partially mediates the effect of bullying on sleep, while resilience weakens the negative impact of distress on sleep, confirming a conditional mediation model. Theoretically, this study advances COR theory by demonstrating how personal resources such as resilience buffer the loss spirals associated with workplace stressors. Practically, the findings highlight the need for IT organizations to strengthen resilience-building initiatives and implement targeted interventions to reduce bullying and protect employee well-being. Full article

Passenger-gathering behavior often triggers safety incidents such as stampedes due to overcrowding, posing significant challenges to public order maintenance and passenger safety. Traditional early warning algorithms for passenger-gathering behavior typically perform only global modeling of image appearance, neglecting the analysis of individual passenger actions in practical 3D physical space, leading to high false-alarm and missed-alarm rates. To address this issue, we decompose the modeling process into two stages: human pose estimation and gathering behavior recognition. Specifically, the pose of each individual in 3D space is first estimated from images, and then fused with global features to complete the early warning. This work focuses on the former stage and aims to develop an accurate and efficient human pose estimation model capable of real-time inference on resource-constrained devices. To this end, we propose a 3D human pose estimation framework that integrates a hybrid spatio-temporal Transformer with three collaborative agents. First, a reinforcement learning-based architecture search agent is designed to adaptively select among Global Self-Attention, Window Attention, and External Attention for each block to optimize the model structure. Second, a feedback optimization agent is developed to dynamically adjust the search process, balancing exploration and convergence. Third, a quantization agent is employed that leverages quantization-aware training (QAT) to generate an INT8 deployment-ready model with minimal loss in accuracy. Experiments conducted on the Human3.6M dataset demonstrate that the proposed method achieves a mean per joint position error (MPJPE) of 42.15 mm with only 4.38 M parameters and 19.39 GFLOPs under FP32 precision, indicating substantial potential for subsequent gathering behavior recognition tasks. Full article

Seaweeds are emerging renewable biomass resources rich in valuable phytochemicals; however, effective stabilization strategies are required to enable their incorporation into sustainable food and bioprocessing applications. This study investigated the effects of convective drying (40–80 °C) and freeze-drying on the chemical composition and functional properties of the underexplored red seaweed Sarcodiotheca gaudichaudii. The drying method significantly modulated nutrient retention, pigment stability, and bioactivity. Freeze-drying and high-temperature convective drying (≥70 °C) resulted in higher protein and saturated fatty acid contents but led to substantial losses of pigments and antioxidant capacity. In contrast, moderate convective drying (40–60 °C) favored the retention of minerals, polyunsaturated fatty acids, essential amino acids, and pigments, while enhancing total phenolic and flavonoid contents and improving antioxidant performance (DPPH and ORAC). All extracts exhibited dose-dependent α-glucosidase inhibition (25–58%) within a concentration range of 0.10–40.0 mg/mL, with freeze-dried samples showing the strongest inhibitory effect. Similarly, cytotoxicity assays conducted on A549 and AGS cancer cell lines at concentrations of 1.25–40.0 mg/mL revealed that freeze-dried extracts consistently displayed the lowest IC₅₀ values. Overall, convective drying better preserved nutritional quality, whereas freeze-drying maintained higher biological functionality, revealing a process-dependent trade-off relevant to industrial biomass stabilization and functional ingredient development. Full article

Paratuberculosis (PTB), caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic intestinal disease in ruminants. PTB is difficult to diagnose, control, and eradicate, leading to substantial economic losses. Thus, sensitive and specific detection methods are urgently required. crRNA and primers targeting the MAP ATPase FtsK gene were designed for recombinase polymerase amplification (RPA) and nested PCR. Fecal DNA was amplified using RPA or nested PCR, purified with Tris-saturated phenol-chloroform-isoamyl alcohol, and detected via CRISPR-Cas12a. Moreover, signals were read using a qPCR instrument, fluorescence reader, or lateral flow strips. RPA–CRISPR-Cas12a and nested PCR–CRISPR-Cas12a assays were optimized and validated on 50 clinical samples and 7 MAP cultures. The limits of detection were 1 × 10⁻¹⁰ μg/μL for RPA–CRISPR-Cas12a and 1 × 10⁻¹⁴ μg/μL for nested PCR–CRISPR-Cas12a. Efficient cleavage of the ssDNA reporter occurred at DNA concentrations of ≥1 × 10⁻⁴ μg/μL, producing a strong fluorescent signal. All three detection methods showed perfect agreement with reference assays across both sample sets. This study presents the first integration of RPA or nested PCR with CRISPR-Cas12a for MAP detection, enabling rapid, specific, and highly sensitive diagnosis. Flexible detection options allow adaptation to available resources and bacterial loads, supporting practical use in PTB control. Full article

The increasing penetration of electric vehicle (EV) fast-charging stations (FCSs) into distribution networks and microgrids poses considerable operational challenges, including voltage deviations, increased power losses, and peak load stress. This work proposes a novel hybrid optimization framework that integrates Lagrangian relaxation (LR) with adaptive sheep flock optimization (ASFO) to address the resource scheduling issues when EVs are penetrated and their impact on net load demand, total cost. Besides the impact of EV uncertainty on energy exchange cost and operational costs, voltage profile deviations were also studied. LR is employed to decompose the original problem and manage complex operational constraints, while ASFO is employed to solve the relaxed subproblems by efficiently exploring the high-dimensional, non-convex solution space. The proposed method is tested on an IEEE 33-bus distribution system with integrated PV and BESS under 24 h dynamic load and renewable scenarios. Results establish that the hybrid LR-ASFO method significantly outperforms conventional methods. Compared to standalone metaheuristics, the proposed framework reduces total cost by 5.6%, improves voltage profile deviations by 2.4%, and minimizes total operational cost by 4.3%. Furthermore, it safeguards constraint feasibility while avoiding premature convergence, thereby accomplishing better global optimality and system reliability. Full article

To promote the sustainable utilization of desert sand as a regional resource in the infrastructure construction of saline-alkali areas, this paper proposes an accelerated test method based on the coupling of an external electric field (60 V) and a 2% Na₂SO₄ solution for rapid evaluation of its sulfate erosion resistance. The optimal mix proportion (FA 10%, water-to-binder ratio 0.33, cement-to-sand ratio 1:1.5, SF 10%) was determined through orthogonal experiments. By employing multi-scale analytical techniques including electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal analysis (TG-DTG), the differentiated deterioration mechanisms driven by the electric field were systematically revealed. The results show that the charge-transfer resistance (Rct) decreased by about 95% within 28 d, demonstrating the characteristic of “micro-scale deterioration preceding macro-scale strength loss.” The anode region was dominated by dissolution of hydration products (porosity 5.1%), while the cathode region, due to enrichment of sulfate ions (S content 3.37 wt.%), generated a large amount of expansive products, leading to more pronounced structural damage (porosity 8.3%) and greater mass loss (cathode 12.56% > anode 9.85%). This study not only elucidates the deterioration mechanisms of desert sand concrete under coupled environmental action, but also provides a mechanism-explicit, rapid and efficient laboratory evaluation method for its sulfate resistance, offering practical guidance for durability design and prevention in engineering structures exposed to saline-alkali conditions. Full article

This study addresses the challenges of low-pressure oil well workover operations, namely, severe loss of water-based workover fluid, significant reservoir damage from conventional temporary plugging agents, and slow production recovery, by focusing on the yet-mechanistically unclear “fuzzy-ball workover fluid.” Laboratory experiments combined with field data were used to evaluate its plugging performance and reservoir-protective mechanisms. In sand-filled tubes (diameter 25 mm, length 20–100 cm) sealed with the fuzzy-ball fluid, the formation’s bearing capacity increased by 3.25–18.59 MPa, showing a positive correlation with the plugging radius. Compatibility tests demonstrated that mixtures of crude oil and workover fluid (1:1) or crude oil, workover fluid, and water (1:1:1) held at 60 °C for 80 h exhibited only minor apparent viscosity reductions of 4 mPa·s and 2 mPa·s, respectively, indicating good stability. After successful plugging, a 1% ammonium persulfate solution was injected for 2 h to break the gel; permeability recovery rates reached 112–127%, confirming low reservoir damage and effective gel-break de-blocking. Field data from five wells (formation pressure coefficients 0.49–0.64) showed per-well fluid consumption of 33–83 m³ and post-workover liquid production index recoveries of 5.90–53.30%. Multivariate regression established mathematical relationships among bearing capacity, production index recovery, and fourteen geological engineering parameters, identifying the plugging radius as a key factor. Larger radii enhance both temporary plugging strength and production recovery without harming the reservoir, and they promote production by expanding the cleaning zone. In summary, the fuzzy-ball workover fluid achieves an integrated “high-efficiency plugging–low-damage gel-break–synergistic cleaning” mechanism, resolving the trade-off between temporary-plugging strength and production recovery in low-pressure wells and offering an innovative, environmentally friendly solution for the sustainable and efficient exploitation of oil–gas resources. Full article

This study evaluates the influence of four unmanned aerial vehicle (UAV) spray nozzle geometries—flat-fan, hollow-cone, air-induction, and ultra-fine electrostatic—on water and pesticide use, canopy coverage, and greenhouse gas emissions in PB-112 rice under field conditions in Saharanpur, India. Across six farms (n = 6), ultra-fine nozzles achieved the greatest reductions in water (41%) and pesticide (43%) volumes, yielding direct pump energy savings of 737 kWh ha⁻¹ and 369 kg CO₂e ha⁻¹, plus further indirect savings from manufacturing. Paired t-tests confirmed highly significant differences (p < 0.001) with large effect sizes. Finer droplets also reduced run-off and evaporation losses by over 60%. These findings demonstrate that nozzle optimization markedly enhances resource efficiency and environmental protection in precision rice spraying. Full article

Background: Congenital hearing loss affects 1–3 per 1000 newborns and requires early detection to prevent developmental delays. Although Thailand implements universal screening, fragmented data systems limit effectiveness. To address this, Chiangrai Prachanukroh Hospital introduced a dedicated newborn hearing screening (NHS) database in 2023 to improve tracking, coordination, and monitoring in a resource-limited setting. Objectives: To evaluate the advantages and limitations of NHS database integration on screening coverage, referral rates, follow-up completion, and diagnostic timeliness. Methods: A retrospective analytic study was conducted over 24 months, comparing outcomes before (July 2022–June 2023) and after (July 2023–June 2024) database implementation. Key indicators included screening coverage, follow-up attendance, diagnostic ABR completion, and workflow efficiency, with the study period also encompassing the implementation of the database and adaptations to the screening algorithm. Data were analyzed using the chi-square test and fisher’s exact tests, supplemented by qualitative observations of system performance. Results: Among 8290 newborns, screening coverage before one month increased from 83.47% to 96.64% (p < 0.001), while referral rates decreased from 18.44% to 6.47% (p < 0.001). Diagnostic ABR completion improved from 7.41% to 52.63% within three months (p < 0.001) and from 59.26% to 84.21% within six months (p = 0.06). The database improved workflow coordination, but challenges persisted, including incomplete data, limited interoperability, caregiver-related follow-up barriers, and low hearing-aid uptake. Conclusions: Integration of the NHS database, as well as protocol changes, improved screening coverage, referral accuracy, and diagnostic timeliness, but follow-up and early intervention barriers persisted. Continued progress will require stronger interoperability, improved family engagement, and digital infrastructure investment, with tele-audiology and decision-support tools helping expand access and efficiency. Full article

One major bottleneck for the sustainable development of the aquaculture sector is the reliance on conventional feed ingredients, such as fishmeal and soy protein. Another challenge is nutrient loss from these systems, which contributes to environmental pollution but also represents a waste of valuable resources. To make aquaculture truly sustainable, a shift toward circular, sustainable systems is necessary. This study compared a regionally available alternative feed, based on blue mussel meal and pea protein concentrate, to a conventional fish meal and soybean control diet in Nile tilapia (Oreochromis niloticus) reared in coupled aquaponic systems. Fish performance and stress levels, water quality, plant growth, and microbial quality were investigated. Growth performance and feed intake were similar between aquaponic and control recirculating aquaculture systems (RASs) during the control feed (CF) phase. Only the feed conversion ratio (FCR) was slightly lower in the aquaponic system during the mussel-pea feed (MPF) phase. Tatsoi (Brassica rapa) growth in the aquaponic systems was comparable to, or even greater than, that of the hydroponic control systems, throughout the experiment, especially during the MPF phase. In addition, the MPF had a positive impact on phenotypic parameters and contributed to enhanced shoot growth. However, the presence of pathogens with potential biohazard impacts on human and fish health remains a concern and warrants further investigation. In our study, Salmonella spp. was detected in both systems, but levels were considerably reduced with the MPF phase. In contrast, Escherichia coli was detected only in RASs and was absent from aquaponic systems. Overall, the findings support the potential of blue mussel and pea protein as sustainable, local feed components in integrated aquaponic production, contributing to nutrient circularity and reducing dependence on limited marine stocks and imported resources. Full article