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Syngas Production from Liquid and Solid Fractions of Swine Manure in a 0.5 kWth Chemical Looping Gasification Unit
No full textSwine manure, a heterogeneous livestock waste composed of solid and liquid excreta, can be sustainably converted through Chemical Looping Gasification (CLG) to produce syngas and bioenergy. Integrated with CO2 capture, the process enables high-purity hydrogen generation and offers a potential route toward net-negative carbon emissions. The experimental campaign was conducted at 900 °C in a continuously operated 0.5 kWth CLG unit consisting of two interconnected fluidized bed reactors (fuel and air). Ilmenite was employed as the oxygen carrier to provide the oxygen required for gasification. This study focuses on the gasification of raw swine manure, comprising both solid and liquid fractions. The solid fraction was introduced via a screw feeder, while the liquid fraction was simulated by injecting an ammonia–water solution as gasifying agents (water or ammonia + water). The effect of the liquid fraction on syngas composition, carbon conversion, and nitrogen species (N2, NH3, N2O, NO2, and NO) was evaluated at ammonia concentrations typical of swine manure (800–5600 mg/L). Results showed an average syngas composition for solid and liquid fraction feeding of ~31% CO2, 20% CO, 41% H2, 7% CH4, and 0.5% C2 hydrocarbons, with 91–96% carbon conversion. Benzene and naphthalene dominated the tar compounds. CO2 capture potential reached 60%, with nitrogen mainly converted to N2
Pathogenic Characterization and Host Immune Response to Vibrio harveyi in Diseased Seriola dumerili
No full textThe greater amberjack (Seriola dumerili) is an economically important marine species that is prone to bacterial infections, resulting in high mortality rates and substantial economic losses. In this study, a virulent bacterial strain, Vh-2, was isolated from diseased greater amberjack and identified as Vibrio harveyi. Experimental infections caused high mortality and severe splenic damage characterized by tissue necrosis, abnormal pigment deposition, cellular disintegration, and extensive immune cell infiltration. A virulence gene analysis revealed that Vh-2 harbored multiple virulence-associated genes such as toxR, toxS, vhpA, vhpB, vhhA, vhhB, luxR, and pap6. Antibiotic susceptibility testing demonstrated ampicillin resistance but sensitivity to ceftriaxone, florfenicol, and meropenem. Transcriptomic profiling of infected spleens identified 396 differentially expressed genes (DEGs) compared to the control group, of which 293 were upregulated and 103 were downregulated. A functional enrichment analysis indicated that these genes were primarily involved in cell cycle regulation, DNA repair, metabolic processes, and immune-related pathways. These findings enhance our understanding of V. harveyi pathogenesis and immune responses of S. dumerili and provide new insights into the prevention and control of V. harveyi infections in marine fish
ServiceGraph-FM: A Graph-Based Model with Temporal Relational Diffusion for Root-Cause Analysis in Large-Scale Payment Service Systems
No full textRoot-cause analysis (RCA) in large-scale microservice-based payment systems is challenging due to complex failure propagation along service dependencies, limited availability of labeled incident data, and heterogeneous service topologies across deployments. We propose ServiceGraph-FM, a pretrained graph-based model for RCA, where “foundation” denotes a self-supervised graph encoder pretrained on large-scale production cluster traces and then adapted to downstream diagnosis. ServiceGraph-FM introduces three components: (1) masked graph autoencoding pretraining to learn transferable service-dependency embeddings for cross-topology generalization; (2) a temporal relational diffusion module that models anomaly propagation as graph diffusion on dynamic service graphs (i.e., Laplacian-governed information flow with learnable edge propagation strengths); and (3) a causal attention mechanism that leverages multi-hop path signals to better separate likely causes from correlated downstream effects. Experiments on the Alibaba Cluster Trace and synthetic PayPal-style topologies show that ServiceGraph-FM outperforms state-of-the-art baselines, improving Top-1 accuracy by 23.7% and Top-3 accuracy by 18.4% on average, and reducing mean time to detection by 31.2%. In zero-shot deployment on unseen architectures, the pretrained model retains 78.3% of its fully fine-tuned performance, indicating strong transferability for practical incident management
A Morphing Land–Air Robot with Adaptive Capabilities for Confined Environments
No full textTraditional wheeled ground robots offer high energy efficiency and excellent mobility on flat terrain but are constrained by their fixed structures, making it difficult to overcome obstacles or adapt to complex environments. To address these limitations, this paper presents a morphing wheeled land–air robot (MW-LAR) that integrates ground locomotion and quadrotor flight. By incorporating foldable arms and variable-diameter wheels, the MW-LAR can not only switch between ground and flight modes, but also achieve transitions between wheeled and legged locomotion in the ground mode. The foldable arms support seamless aerial-to-ground transitions and in-flight morphing, while the variable-diameter wheels facilitate efficient obstacle traversal on the ground. Benefiting from the design of foldable arms, two complementary landing approaches, namely direct quadrotor landing and ground-mode landing, are implemented to explore different aerial-to-ground transition modes and to improve landing safety and switching efficiency. Experimental results demonstrate that the MW-LAR achieves stable and energy-efficient performance across multiple locomotion modes and complex environments, highlighting its potential for integrated land–air mobility applications
Path Planning for Robotic Arm Obstacle Avoidance Based on the Improved African Vulture Optimization Algorithm
No full textTo address the problems of low success rate, excessively long obstacle avoidance paths, and a large number of invalid nodes in path planning for robotic arms in complex environments, this paper proposes an obstacle avoidance path planning method based on the Cauchy Chaotic African Vulture Optimization Algorithm (CC-AVOA). By introducing a Cauchy perturbation term, the algorithm retains a certain degree of randomness in the later stages of the search, which helps to escape local optima. Furthermore, the introduction of a logical chaotic mapping increases the diversity of the initial vulture population, thereby improving the overall search efficiency of the algorithm. This paper compares the performance of the CC-AVOA algorithm with the standard African Vulture Optimization Algorithm (AVOA), the Rapid Exploratory Random Tree (RRT) algorithm, and the A* algorithm through simulation experiments in MATLAB R2024a under two-dimensional, three-dimensional, and robotic arm space environments. The results show that the CC-AVOA algorithm can generate paths with fewer nodes and shorter paths. Finally, the CC-AVOA algorithm is validated on both the RoboGuide industrial simulation platform and a physical FANUC robotic arm. The planned trajectories can be accurately executed without collisions, further confirming the feasibility and reliability of the proposed method in real industrial scenarios
Stability of a Compressed Bar Resting on an Elastic Substrate with Stepwise Changes in Parameters
No full textThe study presents a stability analysis of an axially compressed column resting on a Winkler foundation with a stepwise variation in stiffness. The solution is based on an energy approach using the Rayleigh quotient, and the original buckling mode function is proposed to capture the localization of deformations in the region of foundation discontinuity. The theoretical model was verified numerically for rectangular-section columns by comparing the results with simulations performed in COSMOS/M and ABAQUS systems. The differences in critical load values did not exceed 1.7%. The investigation showed that increasing the stiffness contrast leads to stronger buckling localization within the weaker foundation segment. The developed model can be used for preliminary assessment of the load-carrying capacity of structural elements interacting with a non-homogeneous distributed foundation
Correction: Kingshott et al. Alteration of Metabolic Conditions Impacts the Regulation of IGF-II/H19 Imprinting Status in Prostate Cancer. Cancers 2021, 13, 825
No full textIn the original publication [...
Tribological and Rheological Characterization of 3D Printed Polycarbonate: Effect of Layer Orientation, Surface Topography, and Lubrication Conditions
No full textUnderstanding the tribological behavior of additively manufactured polymers is essential for their reliable use in sliding components. Tribological tests were performed on a linear reciprocating tribometer pin-on-plate configuration using a polycarbonate sample (PC–PC). To assess the influence of additive-manufacturing-induced anisotropy, three build orientations (0°, 45°, 90°) were examined. Two normal loads of 39.24 N and 58.86 N, and two sliding velocities of 15 and 20 mm/s were selected to represent typical low-load operating conditions of polymeric components. Tests were conducted in dry contact and with two commercial lubricants exhibiting distinct rheological characteristics. Surface topography was characterized before and after testing to evaluate orientation-dependent roughness evolution, while rheological measurements provided effective viscosities at shear rates corresponding to imposed velocities. Frictional behavior was analyzed through the Stribeck parameter, showing that all configurations operated within boundary or early mixed lubrication regimes. Longitudinal specimen layer orientation (90°) was expected to give the lowest friction. In fact, dominant lowest friction in most of the examination regimes gave the 45° build orientation, whereas the 0° orientation hindered lubricant entrainment and produced the highest boundary interaction. Differences in lubricant viscosity influenced Stribeck positioning and the magnitude of friction reduction, demonstrating strong coupling between layer orientation, roughness evolution, and lubrication performance
Undernutrition and Feeding Difficulties Among Children with Disabilities in Uganda: A Cross-Sectional Study
No full textBackground/Objectives: Inclusive nutrition services and data on children with disabilities living in low- and middle-income countries remain limited. We estimated the prevalence of undernutrition and described feeding practices and difficulties among children with disabilities ages birth to 10 years at a rehabilitation hospital in Uganda and identified barriers and opportunities for inclusive nutrition. Methods: This cross-sectional study enrolled 428 children. Data included demographics, weight, height, mid–upper arm circumference (MUAC), hemoglobin levels, risk for feeding difficulties, caregiver-reported feeding practices, and functional difficulties complemented by 32 caregiver and stakeholder interviews. Undernutrition was defined using WHO z-scores, MUAC, and anemia cutoffs. Associations were examined using Pearson’s chi-squared tests and adjusted odds ratios from logistic regression. Results: Over half of participants were boys (56.1%) and 65.9% were <24 months old. Common conditions included cleft lip/palate (55.4%) and cerebral palsy (38.6%). Undernutrition was prevalent: 45.2% were underweight, 38.3% stunted, 16.1% wasted (by MUAC), and 39.5% anemic. Being at risk for feeding difficulties (67.2% of children) increased the odds of underweight [AOR = 2.28 (1.23–4.24)], stunting [2.46 (1.26–4.79)], and wasting [2.43 (1.10–5.35)] after adjusting for covariates. Bottle-feeding increased the odds of stunting [3.09 (1.24–7.70)] in infants with cleft lip/palate < 12 months old. Poor access to services, food insecurity, and feeding challenges were key barriers to optimal nutrition. Most caregivers reported using practices that support responsive feeding. Conclusions: Reported barriers to services and high levels of undernutrition, strongly linked to feeding difficulties, underscore the need for targeted feeding interventions and better access to inclusive nutrition services in Uganda
Presence, Participation and Learning in Educational Inclusion: A Systematic Mapping Review of Barriers in School Contexts According to Booth and Ainscow
No full textFrom the perspective of educational inclusion proposed by Booth and Ainscow, the transformation of school systems revolves around three key dimensions: presence, participation and learning. These dimensions constitute the axes of the so-called Inclusion Index and allow for a holistic analysis of the barriers that limit equity and inclusion in school contexts. Based on this theoretical framework, this study aims to systematically map the barriers documented in recent academic literature (2000–2025) that affect these dimensions at the primary and compulsory secondary education levels, with a special focus on intersectional variables that amplify inequalities (gender, migration, disability, mental health, among others)