Search Results (395)

Accurate identification of acid-producing layers is key to controlling acid mine drainage (AMD) in abandoned coal mines. This study collected 337 core samples from 34 boreholes in the Modigou mining area, Shanxi, China, and established a combined static–mineralogical–kinetic approach to evaluate the acid-generating and neutralization potentials of sulfur-bearing rocks. Three-stage net acid generation (NAG) tests identified the pyrite-bearing layer of the Benxi Formation and the No. 10 coal seam of the Taiyuan Formation as the main acid producers, with NAG values of 360.41 and 97.87 kg H₂SO₄/t, respectively, while the Taiyuan limestone showed a high neutralization capacity (ANC = 490 kg H₂SO₄/t). NAG pH was strongly negatively correlated with sulfur content (Pearson r = −0.75, p < 0.01). Sulfide oxidation acid production showed staged attenuation, with average decreases of 64.81% and 47.65% in the second and third stages. Humidity cell experiments demonstrated continuous acid production over 63 days under dry–wet cycles, with increased acid generation rates at higher flow velocities (Darcy flux: 3.54 × 10⁻³ cm/s for accelerated vs. 8.84 × 10⁻⁴ cm/s for standard conditions). Multi-dimensional flow-through simulations confirmed the AMD formation mechanism of “acid supply, buffer, and fracture conduction”. The identified acid-producing layers matched well with field discharge points. This multi-method coupling system provides a theoretical basis for source control of AMD in abandoned high-sulfur coal mines in the Yellow River Basin. This study did not account for microbial catalysis, which is a key limitation of the static chemical oxidation method used. Full article

Background: Early-onset neonatal listeriosis is a rare, life-threatening infection of vertical origin caused by Listeria monocytogenes. First-line therapy is intravenous ampicillin combined with an aminoglycoside; acquired β-lactam resistance is exceptionally uncommon. Case Presentation: A 34-week preterm female neonate (birth weight 1990 g, appropriate for gestational age) was born to a febrile primigravida with fetid greenish amniotic fluid at a regional secondary maternity and transferred at 30 h of life to our tertiary NICU with respiratory failure requiring mechanical ventilation. L. monocytogenes was recovered from blood, gastric aspirate, pharyngeal exudate, ocular secretion, and skin swab. Gradient strip susceptibility testing reported ampicillin and trimethoprim–sulfamethoxazole non-susceptibility, although confirmatory broth microdilution was unavailable. Broad-spectrum empirical therapy was revised on Day 5 to include ampicillin–sulbactam, with piperacillin–tazobactam and gentamicin continued. A follow-up blood culture on Day 9 remained sterile through 7 days. The hospital course was complicated by thrombocytopenia, transiently elevated aminotransferases, and a Grade I subependymal hemorrhage; tertiary NICU length of stay was 25 days. Conclusions: Recovery under a multi-agent regimen precludes attribution of effect to any single component. Discordant gradient strip susceptibility results in L. monocytogenes should be confirmed by broth microdilution before any therapeutic change; survivors of severe early-onset listeriosis require structured multidisciplinary follow-up. Full article

Background: Measles, mumps, rubella (MMR) and varicella vaccines are often co-administered to optimize coverage, yet safety concerns regarding febrile convulsions persist. In South Korea, MMR and varicella vaccines are administered as separate injections during a single visit (MMR + V). This study evaluated the real-world safety of concurrent MMR + V vaccination, focusing on the domestically implemented MAV/06 and Oka-derived strains. Methods: We conducted a multicenter self-controlled case series (SCCS) study of children aged 12–23 months who received MMR + V and hepatitis A vaccine (HAV) between 2015 and 2024. Using electronic health records, we identified predefined adverse events (AEs), including fever and healthcare visits. Adjusted relative risks (aRRs) were estimated using conditional Poisson regression. Results: Among 3035 children (52.3% male; median age, 12 months), 71.7% received the MAV/06 varicella strain. A distinct peak in AEs occurred 7–13 days after MMR + V administration, with fever showing the greatest increase (aRR, 4.27; 95% CI, 2.76–6.60). The risks of total sick visits (aRR, 2.15; 95% CI, 1.70–2.71) and acute care visits (aRR, 2.13; 95% CI, 1.46–3.10) were similarly confined to this interval and returned to baseline thereafter. Febrile convulsions were uncommon (aRR, 5.37; 95% CI, 1.20–24.01). No excess risks were observed during the HAV or overlap periods, and no synergistic effects of intensive multi-vaccine administration were detected. Conclusions: Concurrent administration of MMR and varicella vaccines in Korean infants—predominantly using the MAV/06 strain—was associated only with expected, transient increases in fever during days 7–13 postvaccination. No serious or sustained safety signals were identified, supporting the continued use of Korea’s separate-injection MMR + V strategy. Full article

Rural electrification in Sub-Saharan Africa faces a trilemma: cutting carbon emissions, making it economically viable, and achieving fair access to energy for all. This paper develops a multi-objective framework that optimises carbon revenue, net present value (NPV), total energy supply, cooking fuel (firewood and LPG), health costs, and benefit to society. The model uses continuous decision variables: daily energy allocation among four sources (solar, generator, firewood, LPG) to three population groups (men, women, children). The case study is a rural community of 7000 people in Nigeria (Tier 1 energy consumers). Six policy scenarios are considered: baseline, high carbon price, low carbon price, microfinance, government subsidy and community cooperative. This study compared algorithms and identified a hybrid Non-dominated Sorting Genetic Algorithm and Particle Swarm Optimisation II as the most suitable algorithm for solving the formulated optimisation problem. It was found that NPV and unit cost of energy would increase to $175,500 and 26.4 ¢/kWh, respectively, by increasing the price of carbon from $8/ton to $12/ton. Firewood generates health savings and carbon revenue in the range of $4100–$12,270/year. Prices below $8/ton do not induce optimal reconfigurations in the system. The best energy supply (2825 kWh/day) and the lowest unsatisfied demand occur in the government subsidy scenario with the greatest disparity index, displaying an equity-efficiency trade-off. The framework shows that sustainable access to energy can be unlocked using strategic integration of carbon finance, valuation of health benefits and equity constraints. Full article

In complex urban environments, GNSS satellite signals suffer from severe multipath errors caused by building occlusion and reflection, which significantly degrades the accuracy of precise point positioning (PPP). This paper proposes a deep-learning-based multipath hemispherical grid correction model (DL-MHM) that integrates combined filtering and satellite embedding mechanisms. The model adopts the multi-system interoperable MHM framework to achieve effective multipath error correction. First, pseudorange and carrier phase observation residuals are calculated using the ionosphere-free combination for PPP. Then, a joint median and Kalman filtering scheme is applied to suppress noise in multi-day continuous residual sequences. A transformer-based time-series learning model is constructed, which introduces satellite-specific embedding vectors to characterize the differences between individual satellites and deeply fuse temporal features. This enables the model to adaptively fit the residual variation patterns of different satellites and accurately extract multipath errors. Finally, the multipath components predicted by the deep learning model are incorporated into the multi-system interoperable MHM model to generate the final multipath corrections. Test results show that in heavily obstructed urban scenarios, the root mean square (RMS) values of the east (E), north (N), and up (U) coordinate residuals are improved by 49.27%, 1.80%, and 3.35%, respectively, after DL-MHM correction compared to the uncorrected data. In open-sky environments, the corresponding improvements are 7.70%, 5.48%, and 34.28%. In all experimental scenarios, the proposed method outperforms both the conventional multipath hemispherical map (MHM) model and the convolutional neural network-long short-term memory (CNN-LSTM)-based MHM model in terms of overall multipath correction performance. The experimental results demonstrate that the proposed DL-MHM model can effectively mitigate multipath errors in complex urban scenarios and significantly improve the accuracy of GNSS precise positioning. Full article

Landslide susceptibility is often treated as a static assessment of present-day conditions, overlooking the temporal evolution of geomorphological and anthropogenic drivers. This limitation is particularly relevant in rapidly urbanising areas, where land use change continuously alters environmental conditions influencing slope stability. This study examines the temporal evolution of landslide susceptibility in the Grigorescu neighbourhood of Cluj-Napoca, Romania, using environmental datasets representing conditions in 1971, 2009, and 2025, along with a projected land use scenario for 2047. The proposed framework integrates multi-temporal landslide inventories and conditioning factors with Maximum Entropy (MaxEnt) modelling and CA–Markov–MLP land use simulation (MOLUSCE). Results indicate a progressive shift towards higher susceptibility classes over time, accompanied by urban expansion onto increasingly steep terrain. However, slope gradient remained the dominant conditioning factor throughout all analysed periods, while land use change influenced the temporal evolution and spatial redistribution of susceptibility through progressive urban expansion into terrain already predisposed to instability. The 2047 scenario suggests that continued urban expansion may increase the exposure of built-up areas to zones of elevated susceptibility. Model performance was robust (AUC > 0.8; Kappa > 0.9). Beyond site-specific findings, the framework provides a transferable methodology for integrating urban growth dynamics into landslide susceptibility assessment, supporting sustainable spatial planning and risk-informed urban development in rapidly urbanising hilly environments. Full article

Rapid urbanization has intensified artificial light at night (ALAN) and reduced access to natural dark sky environments. Dark sky parks provide a potential spatial approach for nighttime environmental protection, ecological conservation, and astronomical recreation. This study develops a constraint-based suitability assessment framework for urban dark sky park site selection and applies it to Wuhan, China. Multi-source geospatial data were integrated into a 1 km × 1 km evaluation grid. The AHP–Delphi method was used to determine indicator weights, while land cover constraints were introduced to exclude artificial surfaces from candidate evaluation areas. Weighted overlay analysis, sensitivity analysis, continuous patch screening, and dark sky quality verification were then conducted. The results show that (1) artificial light visibility (ALV) and cloudless days (CVD) are the most important indicators, with weights of 0.328 and 0.250, respectively; (2) 29.38% of the evaluation units are classified as most suitable or more suitable; (3) the spatial pattern of highly suitable areas remain relatively stable, with Jaccard overlap rates of 73.65% and 87.09% under alternative weighting scenarios; and (4) continuous patch screening identifies Caidian and Yangda as priority candidate areas. Further verification using the Bortle Scale, a nine-level classification of night darkness, shows that the Caidian patch reached Bortle class 4 and National Astronomical Observatories (NAOC) dark sky class 1, indicating stronger practical feasibility for dark sky park development. The proposed framework provides a methodological reference for integrating dark sky protection, land use feasibility, and urban planning in metropolitan regions. Full article

Background/Objectives: Regular dialysis sessions impose a fixed schedule on the patient’s days and weeks; this can lead to negative emotions, low mood, helplessness, and a lack of control over their treatment, which significantly reduces the quality of life for these patients. The aim of this study was to assess the mood, level of illness acceptance, and quality of life among dialysis patients undergoing relaxation therapy using virtual reality (VR). Methods: Sixty hemodialysis (HD) patients were recruited for a single-arm study. A personal questionnaire as well as the AIS, PHQ-9, and KDQOL-36™ were used. After one month of the control period, 22 patients were analyzed and then continued with one month of VR relaxation therapy consisting of 360° scenarios or 2D landscape movies. Finally, 16 patients were analyzed for the outcomes during dialysis, three times a week. Results: The data analysis showed a small significant increase in AIS scores after the VR therapy. In the PHQ-9, slight significant reductions in scores were observed at the end of VR therapy. Analysis of the Physical Component Summary (PCS), but not for Mental Component Summary (MCS), results showed statistically significant increases after VR therapy. Conclusions: The study group of dialysis patients showed small but significant improvements in mood, disease acceptance, and quality of life. The VR therapy intervention may be a useful complementary tool to comprehensive treatment and rehabilitation for hemodialysis patients, but multi-center studies are needed for a larger group of patients. Full article

To address the lack of systematic quantitative studies on waterborne epoxy resin (WER)-modified emulsified asphalt regarding its rheological optimization and engineering applicability, this study fills the gap by preparing WER-modified emulsified asphalt via a two-step process. New findings reveal that 20% WER content significantly enhances elastic components, creep–recovery, fatigue life, and fracture energy. The main objective is to establish a theoretical basis for high-performance pavement materials. Modified emulsified asphalt specimens with different waterborne epoxy resin contents were prepared using a two-step method of “emulsification followed by compounding”. The stability of the emulsions was quantitatively evaluated by zeta potential, storage stability, particle size distribution, and demulsification time. Their rheological parameters, multi-stress creep–recovery characteristics, fatigue life, and low-temperature crack resistance were systematically tested across the full temperature range using a dynamic shear rheometer and a bending beam rheometer. In addition, the bonding performance, strength development behavior, and water resistance durability were comprehensively assessed through pull-out tests, Marshall stability and splitting strength tests, as well as freeze–thaw cycle tests. These properties were compared with those of unmodified emulsified asphalt (UEA-0) and SBR-modified emulsified asphalt (SBR-EA). With an increase in waterborne epoxy resin content, the elastic component of the modified asphalt improved significantly, and the phase angle continuously decreased. The specimen with 20% waterborne epoxy resin content (WER-EA-20) exhibited the best performance: its phase angle was lower than those of the other groups under high-, medium-, and low-temperature conditions. After seven creep–recovery cycles, its creep–recovery rate remained at 33%, substantially higher than the 8% observed for the unmodified specimen. The fatigue life reached 15,000 cycles under a shear stress of 2.1 MPa. At −10 °C, the fracture strength was 0.92 MPa, and the fracture energy reached 21.4 J. Furthermore, the pull-out strength of WER-EA-20 was 0.86 MPa, with the failure mode identified as asphalt cohesive failure. After 37 days of curing, the Marshall stability reached 22.5 kN, and the splitting strength was 1.36 MPa. After 40 freeze–thaw cycles, the freeze–thaw splitting strength ratio (TSR) of WER-EA-20 remained above 75%, representing an improvement of more than 110% compared to the unmodified UEA-0 (TSR ≈ 35.5%), which highlights the significant enhancement in water resistance imparted by the waterborne epoxy resin. Compared to SBR-EA, WER-EA-20 has a higher softening point, a lower suitable mixing temperature, and better anti-aging properties. Waterborne epoxy resin can effectively improve the viscoelastic properties and overall road performance of emulsified asphalt, and the modification effect increases with increasing dosage. Full article

The continuous growth of IIoT systems has significantly increased the number of connected devices and message interactions, creating higher requirements for communication mechanisms in terms of scalability and adaptability under dynamic network environments. Although MQTT is widely used for its lightweight communication, its traditional centralized broker architecture limits scalability and fault tolerance in large-scale data transmission, reducing system scalability and fault tolerance. Additionally, static QoS configuration is difficult to adapt to dynamic environmental changes, resulting in high end-to-end latency and limited system throughput. To address these issues, this paper proposes a distributed MQTT communication method based on intelligent QoS routing and hierarchical collaboration (DAIS-MQTT). This method designs a network routing algorithm based on a hierarchical tree structure (LCN), which effectively addresses the scalability limitation of centralized proxies by enabling multi-level proxy collaboration and self-recovery from faults. At the same time, it proposes a QoS routing algorithm based on intelligent decision trees (IQR), which jointly optimizes proxy selection and QoS levels to dynamically adapt to changes in the network environment, thereby solving the problem of insufficient adaptability in static QoS configurations. Experimental results show that compared with the traditional MQTT-based communication method, the DAIS-MQTT method reduces the average message delay by 29.9%, increases system throughput by 28.2%, and maintains a reliable transmission rate of 98.7% in unreliable network environments, making it suitable for high-dynamic and large-scale IIoT communication scenarios. Full article

Background/Objectives: Bronchopulmonary dysplasia (BPD) remains a major morbidity among extremely premature infants, with variability in the application of evidence-based interventions between and within neonatal intensive care units (NICUs). We evaluated a multi-component, risk-guided personalized implementation strategy for BPD prevention in a real-world setting. Methods: We conducted a prospective observational study of infants <29 weeks’ gestation at birth admitted to a quaternary NICU. The intervention combined risk stratification and structured longitudinal care planning rounds (LCPRs) that included standardized documentation, multidisciplinary facilitation, and associated continuous quality improvement strategies. Implementation outcomes were assessed using the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework. Secondary outcomes included care processes, provider-reported measures, and exploratory clinical outcomes. Results: Over six months, 41 infants were included. Risk stratification was consistently applied and all fifteen high-risk infants received LCPR, demonstrating targeted reach. Multidisciplinary participation was broad, with implementation fidelity reflected by consistent screening, structured documentation, and timely care plan execution. Practice standardization was observed, including consistent corticosteroid use (100%), earlier initiation of systemic postnatal steroids (median 16 days), and selective adjunctive therapy use. Providers reported improved teamwork, care coordination, and confidence. Rates of BPD or mortality were comparable between higher-risk infants receiving LCPR and lower-risk infants, despite greater illness severity in the LCPR group. Respiratory severity scores showed a downward trend after implementation, though this did not reach statistical significance (p = 0.07). Strategy use continued beyond the study period indicating early sustainability. Conclusions: A multi-component, risk-guided implementation strategy can be effectively integrated into routine NICU practice, improving care processes while maintaining clinical outcomes in high-risk infants compared with lower-risk infants. Full article

Conventional settlement monitoring techniques are inadequate for seawall construction environments due to severe physical impacts, the absence of terrestrial communication networks, and highly dynamic disturbances. This research proposes a multi-source fusion settlement monitoring system designed specifically for the construction phase to overcome these constraints. An integrated inclinometer–magnetoresistive sensing unit is the central component of this system. The unit achieves physical isolation from the severe impact loads of rock backfilling, guarantees protection in high-salinity and high-humidity environments, and accommodates the large deformations typical of soft foundations by utilizing a structural design that includes a rigid channel steel sheath, anti-corrosion sealing, and flexible joints. In terms of computation, a cascaded attitude fusion framework is developed that combines a Multiplicative Extended Kalman Filter (MEKF) with Quaternion Estimator (QUEST) initialization. High-precision displacement inversion via quaternion rotation is made possible by the introduction of an adaptive mechanism based on the Mahalanobis distance that precisely detects and suppresses transient acceleration disturbances induced by construction machinery and waves. Additionally, data transmission issues in remote offshore areas are resolved by combining solar power and BeiDou short-message communication technologies. This adaptive technique minimizes attitude estimate errors in dynamic situations by approximately 84.56%, as demonstrated by experimental and field validation. The system was deployed as a 165 m array comprising 49 sensing units and monitored continuously for 458 days, achieving a normalized RMSE of 9.44–11.02% compared to reference settlement tubes and capturing a maximum settlement of 1.7 m in the core high-fill section. These results confirm the system’s high monitoring accuracy and resilience in harsh construction conditions. Full article

To address long-duration, high-impact extreme events, this study investigates resilience enhancement optimization dispatching for hydro–wind–solar power systems under continuous multi-day extreme scenarios. A mathematical model is constructed with the resilience objective of minimizing the average load deviation percentage and the economic objective of maximizing the total power generation of the system, while considering constraints such as water balance. The solution steps are provided in this paper. A case study of the Laxiwa hydropower station and nearby wind and photovoltaic power stations demonstrates the following: (1) The compensatory regulation capability of hydropower can be leveraged to enhance power system resilience under continuous multi-day extreme scenarios, and there is a trade-off between resilience and economic objectives. (2) The ability of hydropower to enhance power system resilience is limited by several factors, such as installed capacity, existing reservoir storage, minimum output constraints, and available storage capacity, making it insufficient to fully prevent issues like power shortage, the curtailment of renewable energy, and water spillage. (3) The impact of extreme wind and solar power outputs on the power system exhibits a cumulative effect under continuous multi-day extreme scenarios, and in concurrent scenarios, there is a certain offsetting effect between the impacts of under- and over-generation. This paper provides technical support and a reference for optimizing resilience-oriented scheduling and exploring mechanisms in hybrid hydro–wind–solar power systems under extreme conditions. Full article

Under the global carbon-neutrality target, the technology of carbon capture, utilization, and storage-enhanced oil recovery (CCUS-EOR) faces a severe challenge of carbonation-induced degradation of oil-well cement in harsh downhole environments. Traditional cement suffers serious structural failure under high-temperature and high-pressure CO₂ conditions, whereas single-nanoparticle or polymer modification cannot meet long-term safety requirements. Meanwhile, the comparative study between the “matrix modification strategy” and the “cement system replacement strategy” is still insufficient under real CCUS-EOR conditions. In this study, experimental investigations including macroscopic performance testing, phase analysis, and multi-scale microstructural characterization were conducted. This study systematically evaluates the carbonation resistance of polyaniline@titanium dioxide-modified cement (P@T) and calcium aluminate phosphate cement (CAP). The results show that the carbonation resistance follows the descending order: CAP > P@T > silica-fume-containing Class G oil-well cement (PT). CAP seems to demonstrate a potential “corrosion-induced densification” effect. After 90 days of corrosion, its compressive strength increases to 62.5 MPa, and its permeability decreases to 13.3% of the initial value, indicating continuously improved performance. P@T indicates the possible decoupling of high carbonation degree (CaCO₃ content of 25.26%) and microstructural stability through a structural regulation mechanism of “physical filling–homogeneous distribution of carbonation products”. In contrast, PT undergoes complete structural failure after 60 days. This study fills a gap in comparative evaluation between modification and replacement schemes, reveals the multi-scale structural regulatory effects of P@T and the intrinsic stability of CAP, and provides two reliable cement solutions—“modification enhancement” and “system replacement”—for CCUS-EOR environments. The scientific validity is demonstrated through multi-scale characterization, offering key theoretical and technical support for ensuring long-term wellbore integrity. Full article

The distributed energy system emerges as a promising and valuable technology. However, various factors are hindering the development of the algorithm, including the diversity of units and their respective output constraints. Additionally, the multiple-layer algorithm still faces difficulties searching for the best coordination between integer and continuous variables. To address these challenges, this paper proposes a simultaneous optimization method to aid the design of distributed energy systems. Considering the influence of the outputs of the different units, the proposed method introduces a dual-cycle structure that separates the storage energy units and other units according to the output mode. Additionally, the proposed method yields the hourly outputs of the different units and their respective rated capacities simultaneously. At the same time, an originally designed random walk algorithm with compulsive evolution is integrated into the proposed method. Moreover, a time-series optimization method is applied for the storage energy device to enhance the computational efficiency. To validate the proposed method, the configuration of the distributed energy system (DES) and the hourly output of the different units in three scenarios are analyzed in detail. Quantitative results show that the proposed RWCE-DC reduces the average daily total cost compared to a standard differential evolution algorithm with penalty functions (from 413,628 to 241,716 CNY/day in Scenario II). Across three grid-interaction scenarios, RWCE-DC yields daily costs of 243,271 CNY/day (Scenario I), 209,716 CNY/day (Scenario II), and 178,896 CNY/day (Scenario III) while automatically removing redundant units (e.g., gas boiler in Scenario I) and strictly respecting storage state-of-charge constraints without penalty functions. However, the analysis has several limitations. First, the economic model uses a simplified annualized cost approach without taxes, subsidies, inflation, or discount rate variations. Second, only one geographic location with specific solar and load profiles is considered. Third, the current algorithm focuses on single-objective cost minimization and does not yet incorporate multi-objective trade-offs. These factors should be considered when interpreting the absolute cost values and when applying the method to other regions or policy contexts. These results confirm that the proposed dual-cycle method provides an efficient and numerically validated optimization approach for DES synthesis. Full article