Search Results (42,710)

The social identity of migrant children is not merely a demographic label but is actively constructed and constrained by institutional structures. In China, a rapidly growing migrant population faces stringent institutional barriers, namely cross-regional enrollment policies with restrictive eligibility conditions, which exclude migrant children from local high school education. This study investigates how these structural factors shape the educational decisions and, consequently, the social identity formation of migrant children. Using data from the China Migrants Dynamic Survey and a cohort-based difference-in-differences (DID) approach, we employ an innovative strategy to identify students’ high school enrollment locations by leveraging information on migration timing and birth cohorts. Our findings reveal that strict institutional barriers significantly reduce the likelihood of high school attendance in destination areas, forcing families into a critical trade-off between children’s educational opportunities and family co-residence, which serves as a key site where migrant identity is negotiated. Residence requirements and school-type restrictions emerge as the most binding constraints. Importantly, these policies reinforce the role of household economic capital in accessing education while only partially mitigating disparities linked to cultural capital, suggesting a stratified reproduction of migrant social identities. Mechanism analysis indicates that early co-migration of children serves as a key behavioral channel, illustrating how structural barriers reshape family strategies. Ultimately, this study demonstrates that the educational decisions of migrant families are strongly constrained by institutional arrangements, which in turn shape the salience, meaning, and developmental trajectory of their migrant social identity. Reducing access thresholds and providing more flexible pathways are essential for fostering more equitable identity outcomes. Full article

Ensuring high crop productivity while reducing nutrient losses and environmental impacts remains a central challenge of modern fertilization strategies. Controlled-release fertilizers (CRFs) have emerged as a key tool to synchronize nutrient availability with plant demand by embedding soluble nutrient sources within coatings or matrices that modulate water penetration and ion diffusion. This narrative review synthesizes recent advances in CRF materials and technologies, with particular emphasis on biodegradable and bio-based systems, hydrogels, nanostructured carriers, and extrusion-based matrix formulations. It outlines the main classes of coating and matrix materials, their release mechanisms, agronomic performance, and documented benefits for nutrient-use efficiency, crop yield and quality, and soil and water protection. The review also analyzes major scientific, technical, environmental, and economic barriers that currently limit the large-scale deployment of CRFs, including microplastic pollution from persistent polymer coatings and the difficulty of tailoring release profiles under variable field conditions. Emerging directions are highlighted, such as composite and multilayer bio-based coatings, superhydrophobic and stimuli-responsive structures, biochar- and compost-based matrices, nutrient recovery from waste streams, and integration with precision agriculture and sensor technologies. The paper identifies priorities for future research needed to translate promising CRF concepts into robust, field-validated and sustainable fertilization solutions. Full article

Myocardial bridging (MB) is a congenital coronary anomaly in which a segment of an epicardial coronary artery courses intramurally beneath the myocardium for part of its length, resulting in dynamic compression during systole. Once considered a largely benign incidental finding, accumulating evidence has demonstrated MB to be a clinically significant substrate for myocardial ischemia, arrhythmia, and sudden cardiac death (SCD), particularly under conditions of elevated adrenergic drive such as vigorous physical exercise. The prevalence of MB is highly dependent on the diagnostic modality used, ranging from approximately 0.5–2.5% on coronary angiography to 15–85% on post-mortem and advanced intravascular imaging studies, reflecting a substantial detection gap- in particular on routine cardiac screening tests. This review critically examines the current evidence base regarding MB in the context of competitive and recreational sport. We address: (1) the pathophysiology of exercise-induced hemodynamic compromise in MB; (2) the limitations of existing screening modalities—including electrocardiography, echocardiography, exercise stress testing, and advanced coronary imaging in identifying athletes at risk; (3) the clinical management of symptomatic MB, encompassing pharmacological therapy, coronary revascularization strategies, and catheter-based interventions; and (4) physical activity guidance for athletes with known or suspected MB. Full article

Asthma is one of the most prevalent chronic respiratory diseases worldwide, and environmental pollutants such as desert dust play a significant role in triggering respiratory sensitization and aggravating asthma symptoms. In this study, a mathematical model is proposed to investigate the dynamics of dust-induced asthma progression. The population is divided into unaware susceptible individuals, aware susceptible individuals, dust-sensitized individuals, and asthmatic individuals, while two additional variables describe dust concentration in the human population and the environment. Fundamental qualitative properties of the model, including positivity, boundedness, existence of equilibria, and stability conditions, are established. It is shown that the asthma-free equilibrium is locally and globally asymptotically stable whenever the dust-induced asthma threshold is below unity, whereas a unique asthma-persistent equilibrium exists when the dust-induced asthma threshold exceeds unity. To reduce the burden of asthma, an optimal control problem is formulated by incorporating three time-dependent interventions: awareness campaigns, medical intervention for dust-sensitized individuals, and environmental dust reduction. Pontryagin’s Maximum Principle is employed to characterize the optimal controls and derive the corresponding adjoint system. Numerical simulations, performed using the forward–backward sweep method, demonstrate that the proposed interventions significantly reduce the number of asthmatic individuals compared with the uncontrolled case. Furthermore, a cost-effectiveness analysis based on the Average Cost-Effectiveness Ratio (ACER) and Incremental Cost-Effectiveness Ratio (ICER) is conducted to compare seven intervention strategies. The results indicate that the medical intervention strategy is the most economically attractive option, while the combined strategy involving all controls achieves the largest reduction in asthma burden. Full article

Aberrant cell-surface sialylation is widely associated with cancer progression and provides an accessible molecular feature for biosensing and targeted delivery. However, engineering molecularly imprinted polymer nanoparticles (nanoMIPs) that combine selective sialic acid (SA) recognition with controlled degradability and cytocompatibility remains challenging. In this study, a simulation-guided strategy was used to develop hydrolytically degradable SA-imprinted nanoMIPs incorporating a functionalized lactose-based crosslinker with cleavable ester linkages. Molecular docking and quantum-chemical calculations identified N-isopropylacrylamide (NIPAM), acrylamide (AAm), and N-hydroxyethyl acrylamide (HEAA) as complementary functional monomers and established an optimized SA:NIPAM:AAm:HEAA molar ratio of 1:1:2:1. The resulting nanoMIPs were spherical and nanoscale and exhibited pH-dependent hydrolytic mass loss that was more pronounced under mildly acidic conditions than at physiological pH. Compared with non-imprinted nanoparticles, the nanoMIPs displayed substantially enhanced SA binding, with a maximum binding capacity of 89.38 μmol g⁻¹ and an imprinting factor of approximately 4.2, together with preferential recognition of SA over the selected competing molecules. MTT assays using MCF-7, HeLa, and HaCaT cells showed cell viability above 80% after 24 h exposure to 500 μg mL⁻¹, indicating favorable short-term cytocompatibility. By integrating computationally optimized, multicomponent SA recognition with a carbohydrate-derived, hydrolytically degradable crosslinking strategy, this work addresses the coupled requirements of binding-site fidelity and material degradability within a single nanoMIP platform. These findings establish a materials-level foundation for future SA-directed biosensing and targeted delivery systems in cancer-relevant applications. Full article

Tension-leg platform (TLP) horizontal-axis wind turbines (TLP-HAWTs) have become increasingly important in deep-water offshore wind energy development. However, their performance is strongly affected by coupled platform motions induced by wind and wave loads, making fully coupled simulations a critical prerequisite for accurate performance assessment. Conventional fully coupled approaches often struggle to balance computational efficiency and numerical fidelity. In this study, a simplified sequential coupled modeling framework is proposed based on the commercial solvers OrcaFlex and STAR-CCM+. In this framework, OrcaFlex is employed to simulate the hydrodynamic response of the floating platform, and the resulting platform motions are subsequently imposed as prescribed inputs in high-fidelity CFD-based aerodynamic simulations. Based on the proposed framework, a series of case studies of a 15 MW TLP-HAWT are conducted to investigate the effects of wind-induced and wave-induced platform motions on aerodynamic performance. The results indicate that wind-induced platform motions have a negligible impact on local inflow conditions and vortex intensity, and their influence on mean blade loads and wake topology can be safely ignored under rated conditions. In contrast, wave-induced motions significantly enhance unsteady aerodynamic loads, intensify vortex shedding, alter torque distribution along the blades, and increase wake turbulence intensity as well as velocity deficit. These findings suggest that wave-induced platform dynamics dominate the unsteady aerodynamic response and wake evolution of TLP-HAWTs under rated conditions, while wind-induced motions play a secondary role. The results provide valuable insights for reduced-order modeling, control strategy development, and the design optimization of efficient floating offshore wind turbines. Full article

The international policy framework for “Reducing Emissions from Deforestation and Forest Degradation, plus the conservation, sustainable management of forests, and enhancement of forest carbon stocks” (REDD+) is a vital United Nations Framework Convention on Climate Change (UNFCCC) mechanism designed to assist Global South nations in reaching their climate goals under the Paris Agreement. Implementable at the project, subnational, and national levels, REDD+ has placed an increasing emphasis on subnational program implementation in recent years, exemplified by a growing focus on jurisdictional and integrated landscape strategies. These comprehensive approaches balance diverse land uses and address the complex causes of deforestation through economic incentives and multi-level, cross-sector planning at the state, provincial, or district levels. Ultimately, successful implementation depends on collaboration, active stakeholder engagement, resources, mutual trust, and adequate institutional capacity to manage conflicting local interests. However, weak forestland-use governance in many countries of the Global South often results in inefficient collaborative dynamics that hinder stakeholder cooperation. Despite this, the specific collaborative challenges hindering stakeholder collaboration in subnational REDD+ implementation remain insufficiently understood. To address this gap, this study conducts a literature review to systematically synthesize evidence on subnational REDD+ implementation, using the Integrative Framework for Collaborative Governance (IFCG) to identify key knowledge gaps and challenges. Following established methodological guidance, six databases were searched, Scopus (824), Web of Science (1347), PubMed (84), ResearchGate (557), Google Scholar (571), and Research Rabbit (191), yielding 43 articles on subnational REDD+ implementation for inclusion in the synthesis. The findings identify four main challenges: (i) system context-related challenges, (ii) burdensome global requirements, (iii) resource constraints, and (iv) challenges inherent in the institutional design of collaborative arrangements. While the IFCG proves analytically useful, the complexity and evolving nature of subnational REDD+ programs complicate its application, revealing areas for theoretical refinement. By critically examining the IFCG’s utility, this study advances collaborative governance theory and offers empirical insights into the conditions necessary for effective stakeholder collaboration in subnational REDD+ implementation across the Global South. Full article

Background/Objectives: Congenital chylous ascites is a rare neonatal condition characterized by the accumulation of lymphatic fluid within the peritoneal cavity. The disorder can be difficult to manage, as many infants show limited response to standard conservative strategies such as dietary modification and supportive care. Currently, no universally accepted therapeutic guidelines exist. We report the successful use of propranolol in the management of refractory congenital chylous ascites. Methods: Clinical data were collected from a 35-week preterm male infant who had prenatal ultrasound evidence of fetal ascites from the 28th week of gestation. Postnatal management initially included fasting, total parenteral nutrition, and from day 9 of life, continuous infusion of octreotide. Due to the persistent ascites, oral propranolol was added to the therapy on the 31st day of life. Current literature was reviewed to compare our findings with those available. Results: Following the addition of propranolol to ongoing octreotide therapy, the infant demonstrated gradual clinical improvement with decreased abdominal distension and reduction of ascitic fluid; as propranolol and octreotide were administered concurrently for approximately 30 days, a causal effect could not be isolated to propranolol alone. Oral propranolol was administered at 0.5 mg/kg every 6 h (2 mg/kg/day total), with heart rate, blood pressure, and glucose monitored throughout treatment; no propranolol-related adverse events (bradycardia, hypotension, bronchospasm, hypoglycemia, or feeding intolerance) occurred. Ultrasonographic resolution of ascites was achieved by day 48, the peritoneal drainage catheter having already been removed on day 34; propranolol was subsequently tapered and discontinued by day 68, and the patient was discharged in stable condition on day 93, with no recurrence on serial ultrasound over the 45 days from resolution to discharge. A narrative review of the literature identified nine infants with lymphatic disorders successfully treated with propranolol. Conclusions: This case suggests a possible temporal association between propranolol administration and clinical improvement in a neonate with congenital chylous ascites refractory to conventional management; no propranolol-related adverse events were observed during treatment. Given the rarity of this condition and the absence of standardized treatment guidelines, further studies—potentially through multicenter registries or prospective case series—are warranted to establish optimal dosing strategies, evaluate long-term outcomes, and clarify the role of propranolol in this setting. Full article

To effectively address the challenges of complex spatiotemporal conflicts, dynamic obstacle avoidance, and coordinated multi-objective optimization in preemptive multi-UAV logistics delivery within complex airspace, this study proposes a Hybrid Improved Multi-Objective Cuckoo Search algorithm (HI-MOCS) for preemptive multi-UAV cooperative logistics scheduling and planning. To overcome the limitations of conventional MOCS, including a low proportion of feasible solutions under complex constraints, susceptibility to local optima, and uneven distribution of multi-objective solution sets, a multi-constraint physical model and a multidimensional evaluation framework are established for preemptive scheduling. A positive knowledge-transfer mechanism based on the co-evolution of primary and auxiliary populations is developed, in which constraint-violation information is used to guide infeasible solutions toward the feasible region. A hybrid heuristic population initialization strategy combining emergency-order priority and spatial scanning rules is introduced to increase the proportion of high-quality feasible solutions in the initial population. In addition, a nonlinear dynamic adaptive parameter-adjustment strategy is designed to balance global exploration and local exploitation, while an iterative truncation-based environmental selection mechanism using the shortest-distance criterion is employed to improve the distribution quality of the Pareto solution set. The experimental results show that, in the benchmark scenario, HI-MOCS achieves an average increase of 33.26% in the total order completion rate and an average reduction of 15.34% in emergency response time compared with 11 multi-objective optimization algorithms, while also exhibiting favorable performance in terms of flight distance per completed order. The fleet-size analysis shows that the 15-UAV configuration achieves the lowest best mean fitness. The safety-distance analysis indicates that, compared with the other safety-distance settings, the 30 m setting increases the total order completion rate by an average of 26.55%, while reducing emergency response time and flight distance per completed order by 27.36% and 33.72%, respectively. The task-scale analysis shows that the 50-order scenario achieves the lowest best mean fitness. Further ablation experiments demonstrate that, compared with the average performance of MOCS and the four single-strategy variants, the complete HI-MOCS improves the total order completion rate by 20.27%, while reducing emergency response time and flight distance per completed order by 20.71% and 36.18%, respectively. The HV, IGD, and Pareto-front results further confirm that the synergistic effects of the four improvement mechanisms effectively enhance the multi-objective optimization performance and the quality of the nondominated solution set. The current study is still validated under simulation conditions assuming reliable GNSS positioning and communication links, without explicitly considering communication delays. Full article

This work presents a covariance-aware extension of the hybrid nonlinear-kicker (NLK) injection framework. While previous baseline studies established centroid action reduction and hardware-aware NLK placement for idealized beams, the present study addresses finite-beam optimization using a realistic, position-dependent eight-wire kick profile. A realistic NLK field not only corrects the injected-beam centroid but also induces an amplitude-dependent shear across the internal phase-space ellipse. Depending on the injected covariance and ellipse orientation, this shear can either reduce or enhance beam filamentation. To exploit this mechanism, the AC-septum angle is treated as a trajectory-control knob for the injected centroid, while transfer-line matching is used to control the injected covariance matrix. We use ID2-downstream as the primary optics-favored case, as its high ${\beta }_N$ simultaneously increases nonlinear-field sampling and reduces the required correction kick. Furthermore, at this location, the injected beam is close to a matched, near-upright covariance condition (${\alpha }_{beam}\approx 0$). We also examine ID1 middle and ID1 downstream as trajectory-controllable alternatives, and formulate a combined optimization over septum angle, transfer-line optics, and NLK current. Operational measurements of AC-septum stability, first-turn trajectory reproducibility, septum response, and injection-bump response validate the available trajectory-control authority required for realistic NLK optimization. The analysis identifies a residual oscillation floor proportional to the square of the remaining centroid offset and inversely proportional to the local beta function, demonstrating that the physically relevant objective is minimization of the final mean action after the realistic NLK kick, rather than percentage action reduction alone. This framework establishes a practical optimization strategy under realistic aperture, stability, and hardware constraints. In a representative covariance-matched ID2D case, the realistic eight-wire NLK reduces both mean horizontal action (from 3.372 μm to 0.382 μm) and finite-beam spread contribution (from 0.475 μm to 0.039 μm). Operationally, first-turn rms trajectory variations remain under 0.4 mm, and the measured trajectory response of 19.4 mm/mrad closely matches the 19.8 mm/mrad model. Full article

Soil water erosion is one of the most serious environmental problems worldwide, with major consequences for agricultural output, food security, and terrestrial ecosystems, particularly in the Mediterranean basin. This study compares modelled soil-loss conditions across Andalusia, Spain (87,268 km²), between the 2018 and 2025 reference years using a cloud-based implementation of the Revised Universal Soil Loss Equation (RUSLE) in Google Earth Engine (GEE). The framework couples daily precipitation data from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) at its native information scale of approximately 5.5 km, 10 m satellite imagery, and a machine learning-derived, year-specific soil-erodibility update on a common 30 m output grid. The regional mean annual soil loss in 2025 (45.86 t ha⁻¹ yr⁻¹) was 24.98% higher than in 2018 (36.70 t ha⁻¹ yr⁻¹). The 2025 reference year also showed a 12.28% higher R-factor and a 7.83% higher C-factor. The area under Severe erosion (>50 t ha⁻¹ yr⁻¹) increased from 16,330 to 20,636 km² (+26.37%). Exact signed Shapley attribution on the common erodible support assigned +7.43, +3.52, +0.23, and −2.70 t ha⁻¹ yr⁻¹ to R, C, P, and K, respectively. These results describe a marked contrast between two modelled reference years without establishing a continuous trend or causal change, and demonstrate a transparent framework for regional erosion screening to support sustainable land-use planning and soil-conservation strategies. Full article

Background/Objectives: Post-stroke epilepsy represents one of the most frequent and impactful long-term sequelae of pediatric arterial ischemic stroke. Children are particularly vulnerable to developing seizures and epilepsy after stroke, likely because the immature brain responds differently to ischemic injury than the adult brain. The purpose of this narrative review is to summarize the current evidence regarding the epidemiology, risk factors, mechanisms, and clinical implications of post-stroke epilepsy following pediatric arterial ischemic stroke. Methods: We conducted a narrative review to examine the incidence, determinants, risk stratification, and long-term outcomes of post-stroke epilepsy following childhood arterial ischemic stroke beyond the neonatal period. Results: The reported incidence of post-stroke epilepsy in children varies considerably across studies, ranging from approximately 7% to over 40%. However, recent data suggest that roughly one in four children who experience an arterial ischemic stroke will eventually develop epilepsy, highlighting the substantial long-term burden of this condition. Acute symptomatic seizures, particularly very early seizures and acute status epilepticus, consistently emerge as the strongest predictors of subsequent epilepsy, with recent pediatric meta-analytic data suggesting an approximately fourfold increased risk of post-stroke epilepsy. Cortical involvement and persistent neurological deficits also represent robust predictors of post-stroke epilepsy (PSE), whereas younger age at stroke onset, multifocal infarctions, greater infarct burden, anterior circulation involvement, and focal cerebral arteriopathy have been associated with an increased risk. Emerging evidence further suggests a possible contribution of genetic susceptibility and potentially modifiable biological factors, such as vitamin D deficiency, to epileptogenic risk. Conclusions: This narrative review summarizes current evidence regarding the incidence, determinants, and pathophysiological mechanisms of post-stroke epilepsy following childhood arterial ischemic stroke, highlighting established and emerging risk factors and their implications for long-term risk stratification, clinical management, and future preventive strategies. Full article

Predicting target intent in complex, dynamic multi-agent environments remains a formidable challenge due to incomplete perception and the highly dynamic nature of multi-target interactions. Conventional approaches—such as D-S evidence theory, expert systems, and Recurrent Neural Networks (RNNs)—are often constrained by data incompleteness and rigid behavioral assumptions, limiting their adaptability to dynamic high-value target identification and multi-target situational awareness on the ground. To address these challenges, a novel framework termed Threat Field–Gated Recurrent Unit (TF-GRU) is proposed. The TF-GRU framework integrates threat field modeling with a dynamic repair mechanism to enhance intent prediction under partial perception. Specifically, threat field modeling associates target attributes with intentions through the construction of static and dynamic threat fields, effectively capturing the temporal and semantic relationships among multiple targets. A particle filtering and dynamic time warping fusion strategy (PF-DTW) is employed to repair data gaps via short-term filtering and long-term trajectory matching, further refined by a neighborhood-angle constraint for accurate multi-target state estimation. In addition, trajectory and threat field features are processed using a Mish activation function and a threat-adaptive gating mechanism, which dynamically regulate information flow within the recurrent unit to model behavioral evolution. Experimental evaluations demonstrate that TF-GRU significantly enhances intent prediction accuracy under incomplete data conditions, thereby improving comprehensive situational awareness and supporting high-confidence decision-making in dynamic multi-target scenarios. Full article

Microgravity research has emerged as a rapidly evolving field at the intersection of space medicine, genomics, biotechnology, and precision medicine. Exposure to the space environment induces complex physiological and molecular adaptations that affect multiple biological systems, including immune regulation, metabolism, musculoskeletal function, and gene expression. Recent advances in genomics, multi-omics technologies, artificial intelligence, and bioengineering have substantially improved our understanding of biological adaptation to spaceflight and expanded opportunities for translational biomedical research. This review summarizes recent advances in genetic and biomedical research under microgravity conditions, with particular emphasis on molecular mechanisms, omics technologies, genome editing, microbiome research, regenerative medicine, and personalized healthcare approaches. Major experimental platforms, landmark spaceflight studies, and translational applications in infectious diseases, cancer biology, aging, tissue engineering, and pharmaceutical development are discussed. The review also highlights Saudi Arabia’s emerging contributions to genomic medicine and space biosciences through initiatives such as the Saudi Human Genome Program, the Saudi Pangenome Project, the Saudi Space Agency, and the BioGravity Initiative. Recent Saudi participation in human spaceflight and microgravity-associated biomedical research is discussed within the context of Vision 2030 and national investments in biotechnology and precision medicine. Collectively, advances in microgravity research are expected to contribute to the advancement of precision medicine and facilitate the development of innovative diagnostic and therapeutic strategies with significant implications for both human space exploration and terrestrial healthcare. Full article

Background: Subvalvular aortic stenosis (SAS) is an important cause of fixed left ventricular outflow tract obstruction and the second most common form of aortic stenosis. Although traditionally considered a congenital lesion, increasing evidence suggests that SAS often behaves as a progressive condition influenced by anatomical and hemodynamic factors. The disease may lead to significant complications, including left ventricular hypertrophy and progressive aortic regurgitation. Materials and Methods: A narrative review of the current literature was performed to summarize contemporary knowledge regarding the epidemiology, pathophysiology, clinical presentation, diagnostic evaluation, and management of subvalvular aortic stenosis. Relevant studies were identified through searches of major medical databases and were critically analyzed to provide an overview of current concepts and clinical practice. Results: Subvalvular aortic stenosis demonstrates considerable anatomical and clinical heterogeneity, ranging from discrete subaortic membranes to fibromuscular tunnel-type obstruction. The condition often progresses over time, with increasing LVOT gradients and a high incidence of associated aortic regurgitation. Echocardiography remains the primary diagnostic modality, while advanced imaging techniques provide additional anatomical detail and assist in surgical planning. Surgical resection remains the cornerstone of treatment when significant obstruction or related complications develop. Conclusions: Subvalvular aortic stenosis is a complex and progressive disease requiring careful imaging assessment and timely surgical management. Although surgical outcomes are generally excellent, recurrence and progressive aortic valve involvement remain important long-term considerations. Ongoing research aimed at improving risk stratification and optimizing surgical strategies may further enhance patient outcomes. Full article