Search Results (1,941)

Background and Aims: Helicobacter pylori is a major cause of chronic gastritis and peptic ulcer disease. The increasing global spread of antibiotic-resistant strains, particularly against amoxicillin and clarithromycin, poses a significant challenge to eradication therapies. Moreover, treatment-related adverse effects, often linked to antibiotic-induced intestinal dysbiosis, frequently lead to a poor patient compliance; this, in turn, promotes the persistence of resistant bacterial populations. Probiotics may mitigate these effects and improve treatment adherence. This study aimed to assess the genomic safety of new probiotics intended for adjuvant use in H. pylori eradication regimens. Methods: Whole-genome sequencing was performed on three probiotic strains: one of Lactobacillus acidophilus, and two of Bifidobacterium animalis subsp. lactis. Genomes were compared with corresponding wild-type reference strains to identify genetic variations and detect mobile genetic elements. Results: Comparative genomic analysis revealed differences between selected and wild-type strains. Importantly, no plasmids or transposons were identified, suggesting a reduced theoretical risk of horizontal transfer of antimicrobial resistance determinants. Genomic findings were consistent with in vitro phenotypic observations. Conclusions: Whole-genome sequencing provided a robust assessment of the safety profile of these strains. The absence of transferable resistance elements supports their potential use as probiotic candidates to improve tolerability and adherence to H. pylori eradication therapies, contributing to more effective treatment outcomes. Full article

Compression tests are widely used to characterize cereal kernels, yet the loading rate is often treated as a secondary methodological factor, despite the fact that the ASAE S368.4 procedure recommends a low crosshead speed, whereas industrial size-reduction operations involve much faster and more complex loading conditions. This mismatch limits the direct transfer of laboratory data to milling practice and makes it difficult to compare results obtained under different test settings. The aim of this study was therefore to determine how grain moisture content and loading rate (crosshead speed) affect kernel damage and selected mechanical properties of bread wheat cultivars (Bataja and Tytanika) and feed wheat cultivars classified in the Polish C quality group (Lawina and Sikorka). Before the analyses, kernels were adjusted to five moisture levels: 10%, 12%, 14%, 16%, and 18% on a wet basis (w.b.). Compression tests were conducted at six crosshead speeds: 1, 3, 5, 10, 30, and 50 mm min⁻¹. The conversion ratio of mechanical properties determined relative to 1 mm min⁻¹ and 10% moisture content ranged from 0.46 to 2.59, confirming that both factors markedly changed kernel response. Rupture force generally decreased with increasing moisture content, whereas longitudinal strain, relative strain and rupture energy increased. A distinct decrease in all mechanical parameters was observed at 10 mm min⁻¹, and this effect became more pronounced at higher moisture contents. The results indicate that the loading rate should be reported and controlled in wheat kernel compression tests and should be considered when laboratory measurements are used to support milling optimization. However, the proposed value of 10 mm min⁻¹ should be interpreted as a promising laboratory reference point rather than as a direct industrial operating standard. Full article

Quadriceps muscle and tendon injuries are a significant cause of impairment of the knee extensor mechanism, ranging from minor muscle strains to complete tendon ruptures and extensive defects following oncologic resections. This narrative review provides a comprehensive analysis of contemporary concepts in anatomy, biomechanics, diagnosis, surgical management, and rehabilitation, with a particular focus on reconstructive techniques and functional outcomes. While most muscle injuries respond well to conservative management, complete quadriceps tendon ruptures typically require surgical repair to restore extensor continuity. Both transosseous suture techniques and suture anchor fixation demonstrate reliable outcomes, with no clear superiority in clinical results. Chronic ruptures present additional challenges due to tendon retraction and poor tissue quality, often necessitating advanced reconstruction methods such as V–Y tendon lengthening and augmentation with autografts, allografts, or synthetic materials. In cases of large defects, especially following soft-tissue sarcoma resection, free functional muscle transfer (FFMT) has emerged as a key reconstructive strategy. Common donor muscles include the latissimus dorsi, gracilis, rectus abdominis, and vastus lateralis, each offering specific biomechanical advantages. Functional recovery is strongly influenced by the extent of quadriceps preservation, with better outcomes observed when at least two muscle heads remain functional. Rehabilitation protocols vary depending on the surgical approach. Early controlled mobilisation is generally recommended after tendon repair, whereas FFMT requires a more cautious and prolonged rehabilitation process to allow for flap integration and reinnervation. Overall, optimal outcomes depend on a multidisciplinary approach combining appropriate surgical technique, individualized rehabilitation, and careful patient selection. Full article

Graphene, with its excellent mechanical and electrical properties, is an ideal candidate material for constructing high-performance piezoresistive sensors. However, lattice defects inevitably introduced during its preparation and transfer processes can significantly alter its electronic structure, thereby affecting the sensing performance of the devices. Based on first-principles calculations, this work systematically investigates the effects of monovacancy defect concentrations ranging from 2% to 8% on the geometric structure, electronic structure, and piezoresistive performance of graphene. The results show that monovacancy defects induce local lattice distortions and bond reconstructions, forming 5–9 non-hexagonal ring structures at defect concentrations of 4% and 8%. In terms of electronic structure, the defects break the lattice symmetry and open a band gap. High concentrations of defects lead to severe overlapping of electronic states, causing the band gap to first increase and then decrease with increasing defect concentration, reaching a maximum value of 0.697 eV at a concentration of 6%. Meanwhile, the defects introduce localized electronic states, enhance the electron localization effect, and render the system p-type doped. Regarding piezoresistive performance, monovacancy defects significantly improve the gauge factor of graphene. At a defect concentration of 6%, the gauge factor reaches 118.23, which is approximately 36 times that of pristine graphene. These findings reveal the microscopic mechanism of strain-dependent electronic modulation in defective graphene and provide theoretical support for defect engineering design in high-performance graphene-based piezoresistive sensors. Full article

With the rapid expansion of urban underground space in China, anti-floating has become a critical challenge, and uplift piles are a key solution. Previous studies on composite anchor-cable uplift piles have primarily focused on small-diameter single-pipe types (≤600 mm), often simplifying the pile as an integral component, leaving the multi-interface stress transfer mechanisms of large-diameter piles inadequately understood. This study proposes a back-analysis method based on orthogonal experiments, implemented using Abaqus 3D finite element software, to determine interfacial mechanical parameters for three critical contact pairs (strand-grout, grout-steel pipe, steel pipe-concrete) in large-diameter multi-pipe composite anchor-cable uplift piles. These parameters are then implemented in a refined 3D finite element model to simulate the load-deformation behavior of such piles. Quantitative results show that the back-calculated parameters are highly reliable, with maximum simulation errors for pile head displacement limited to 13.0% and 9.6% for fully bonded and semi-bonded piles, respectively. Unlike conventional piles, stress and strain in this new pile type transfer progressively from the inner steel strands outward and from the top downward, resulting in reduced pile-soil displacement mismatch, fuller mobilization of side interfacial strength, and effective mitigation of concrete cracking. This study provides a systematic parameter-calibration framework and numerical platform, offering theoretical and technical support for optimized design and engineering application of large-diameter composite uplift piles. Full article

Cyanobacteria inhabit ecosystems ranging from oligotrophic deserts to eutrophic lakes, yet it remains unclear whether distantly related species dominate in disparate habitats, share common genomic features, or show divergent specialization. Here, we established a comparative framework of Microcoleus vaginatus, the pioneer stabilizer of biocrusts, and Microcystis aeruginosa, a major cause of freshwater blooms worldwide. Our dataset comprises 504 high-quality cyanobacterial genomes, including 132 M. vaginatus, 148 M. aeruginosa, and 224 reference taxa, for analyses of genome architecture, functional repertoires, and genomic plasticity. Both focal lineages showed signatures of extensive horizontal gene transfer and shared a small set of conserved orthologous groups, annotated as FAD-dependent oxidoreductases, manganese efflux, and class II aldolases. Nevertheless, the two lineages followed distinct genomic strategies. M. vaginatus expands regulatory breadth and stress-resilience gene families, whereas M. aeruginosa shows evidence of genome streamlining and rapid nutrient exploitation. Notably, we hypothesize that aquatic M. vaginatus strains retain ancestral terrestrial genomic features while gradually acquiring potential aquatic-specific adaptations. Together, these results reveal a two-tier architecture associated with cyanobacterial dominance and provide a testable hypothesis for how cyanobacterial lineages may respond to global change pressures. Full article

Structural health monitoring (SHM) of fibre-reinforced composites requires a health indicator that is monotonically non-decreasing under the standard SHM assumption that no self-healing or maintenance-induced restoration event is active, derived from heterogeneous sliding-window observations of acoustic emission, strain, and fibre Bragg grating channels, with only the failure timestamp available per specimen. Conventional endpoint-supervised regressors attain high rank correlation with normalised life but produce jagged, non-monotone trajectories of limited engineering value. A method named SAMS-Net (Smoothness-Anchored Monotone Neural Differential Equation Network) is developed, in which a neural differential equation backbone is anchored by a two-level Pool-Adjacent-Violators (PAV) projection. A within-window projection is applied during training with a straight-through gradient, and an across-window projection is applied at inference, yielding a globally non-decreasing health indicator. A smoothness-stratified two-phase training schedule first trains on specimens whose per-specimen median local-smoothness coefficient exceeds 0.5, then fine-tunes on the full set. Across the present seventeen-specimen open-hole carbon-fibre dataset spanning two stress levels and six leave-one-specimen-out and cross-condition scenarios, SAMS-Net wins on every scenario on the canonical Prognostics and Health Management (PHM) Composite of monotonicity, trendability, and robustness, with margins of 0.22 to 0.48 against the strongest baseline, reproducible across three random seeds. Ablation reveals that the operative mechanism is the two-level PAV projection rather than the stochastic differential equation (SDE) inductive bias. A new control experiment in which the across-window PAV projection is applied at inference to the strongest baselines confirms that the projection accounts for a substantial share of the SAMS-Net margin, while the within-window training-time projection and a globally consistent prognosability metric retain a SAMS-Net advantage. Cross-site or cross-material transferability remains to be established in future work. Full article

To address issues such as deformation and stress concentration that are prone to occur in pure electric passenger vehicle electric drive housings under complex working conditions, an integrated electric drive housing was taken as the research object for finite element simulation analysis and improvement tests. A finite element model of the housing was established based on ABAQUS to analyze the strain and stress of the housing and its deformation patterns under load. In response to issues such as bearing abnormal noise and seal failure caused by housing deformation, a method was proposed to enhance the structural rigidity of the housing and improve the load transfer path of the housing, which was verified through bench tests. The results showed that the maximum deformation of the improved housing decreased by 42.7%, the stress and strain in key areas were controlled within the design allowable range, and the failure rate approached zero, meeting the engineering design requirements. Full article

The utilization of existing telecommunication infrastructure for environmental monitoring via opportunistic sensing is rapidly advancing the field of distributed fiber optic sensing (DFOS). However, while custom-engineered sensing cables are highly characterized for hydrostatic pressure, the complex mechanical response of standard armored telecommunication networks remains largely unquantified. This study experimentally investigates the non-linear distributed pressure sensitivity of three commercial telecommunication cables (Anti-Rodent, Duct, and Microcable) across a hydrostatic pressure range of 0 to 800 PSI. Measurements were conducted using Tunable Wavelength Coherent Optical Time Domain Reflectometry (TW-COTDR) with a 20 cm spatial resolution, utilizing a stepped depressurization protocol with 15-min stabilization holds to isolate true steady-state longitudinal strain. The results reveal that protective cable armoring induces severe mechanical non-linearity. The rigid Glass Reinforced Plastic (GRP) rods of the Anti-Rodent cable acted as a structural vault at low pressures before yielding to become highly sensitive above 400 PSI. Conversely, the corrugated steel tape of the Duct cable exhibited high initial sensitivity followed by mechanical stiffening, while the unarmored Microcable maintained a linear response. These findings establish that a single linear calibration coefficient is invalid for heavily armored infrastructure, highlighting the critical need for structural characterization prior to opportunistic field deployments. Full article

Pathogenicity islands (PAIs) are regions of bacterial genomes that harbor genes encoding virulence factors. Identifying molecules that enhance pathogenicity is crucial for understanding the mechanisms pathogens employ to cause disease and their evolution. Corynebacterium pseudotuberculosis (C. pseudotuberculosis) is a pathogenic microorganism that causes caseous lymphadenitis (CLA) in sheep and goats. Despite its prevalence in Mexico, its genetic material has not been analyzed for virulence factors acquired through horizontal gene transfer. Therefore, the aim of this study was to characterize the complete genomes of Mexican C. pseudotuberculosis strains and identify virulence-related genes harbored with PAIs. Seventeen strains of C.pseudotuberculosis biovar ovis isolated from Mexico were whole-genome sequenced using illumina technology, assembled de novo with SPAdes, and annotated using Prokka. PAIs were predicted with GIPSy based on genomic signatures associated with horizontal gene transfer, including G + C deviation, codon usage, virulence factors, transposases, and tRNA-flanking regions. Positive selection was assessed using POTION v1.2 by identifying orthologous groups enriched in non-synonymous substitutions. This represents the first comprehensive PAI analysis of Mexican C. pseudotuberculosis strains, identifying 14 putative pathogenicity islands harboring 51 virulence-associated genes. Additionally, positive selection analysis identified five coding sequences, including radA and rpiB, that are undergoing adaptive evolutionary changes. These findings elucidate the pathogenic mechanisms and genomic plasticity of Mexican C. pseudotuberculosis strains. They also highlight novel genetic targets for vaccine and therapeutic development against CLA. Full article

Recent technological advances and the reinvigoration of NASA’s Artemis program have increased the feasibility of lunar habitats and supporting infrastructure, necessitating the development of specialized foundation systems capable of maintaining stability under transferred structured loads. Site investigation techniques, including in situ testing, sampling, and geophysical mapping, must therefore be adapted for lunar conditions, while construction using regolith requires an improved understanding of lunar soil mechanics. Foundations must also endure extreme thermal fluctuations, reduced gravity, radiation exposure, micrometeoroid impacts, and lunar seismicity to ensure long-term performance. Consequently, enhanced knowledge of the monotonic and cyclic geotechnical behavior of lunar soils is essential. Owing to the limited availability of in situ testing opportunities and returned lunar materials, high-fidelity simulants that replicate regolith behavior are required for experimental studies. This research investigates the static behavior of several contemporary lunar simulants and compares their responses with terrestrial benchmark soils. The results indicate that the overall stress–strain trends of lunar simulants broadly resemble those of terrestrial soils; however, the particle morphology and distinctive mineralogical compositions, including basaltic and anorthositic constituents, yield higher values of certain geomechanical parameters. Comparison with terrestrial datasets further suggests that carefully selected benchmark soils may facilitate the development of a next generation of lunar simulants with improved fidelity to lunar regolith. Full article

Serratia spp., particularly Serratia marcescens, have emerged as clinically important opportunistic pathogens and are increasingly recognized as causes of healthcare-associated infections, especially among critically ill and immunocompromised patients. Their remarkable ecological adaptability, persistence in hospital environments, and capacity to acquire multiple antimicrobial resistance determinants have contributed to the global emergence of multidrug-resistant strains and complicated therapeutic management. This review aims to comprehensively analyze the epidemiology, virulence mechanisms, antimicrobial resistance patterns, and current and emerging therapeutic strategies associated with Serratia spp. The manuscript is based on a critical review and analysis of previously published literature retrieved from electronic scientific databases focusing on clinically relevant Serratia spp. infections and resistance trends. The reviewed literature demonstrates that Serratia spp. combine intrinsic resistance mechanisms, particularly inducible chromosomal AmpC β-lactamases, with acquired resistance determinants including extended-spectrum β-lactamases, carbapenemases, aminoglycoside-modifying enzymes, and plasmid-mediated quinolone resistance. Horizontal gene transfer and biofilm formation further enhance bacterial persistence, dissemination, and adaptation within healthcare settings. Clinically, these pathogens are associated with device-related infections, bloodstream infections, pneumonia, urinary tract infections, and hospital outbreaks, where increasing multidrug and carbapenem resistance significantly limits therapeutic options. Novel β-lactam/β-lactamase inhibitor combinations and cefiderocol represent promising therapeutic approaches, although treatment success remains highly dependent on accurate identification of underlying resistance mechanisms. This review highlights the growing public health importance of Serratia spp. and underscores the need for improved surveillance, molecular diagnostics, antimicrobial stewardship, and the development of innovative therapeutic strategies in the context of the evolving antimicrobial resistance crisis. Full article

Skeletal muscle mechanics arise from hierarchical fiber–matrix interactions spanning multiple length scales. This study presents a computationally efficient, composite-inspired multiscale finite element framework that links muscle microstructure to whole-muscle behavior through explicit periodic numerical homogenization. Muscle fibers and endomysium are resolved at the microscale, their homogenized response is propagated to fascicles embedded in the perimysium at the mesoscale, and the resulting properties are incorporated into a three-dimensional macroscale muscle model including the epimysium. Unlike phenomenological continuum models or computationally intensive chemo-electro-mechanical approaches, the proposed framework enables scalable three-dimensional simulations while preserving microstructural load-transfer mechanisms. The predicted stress–strain relationships in uniaxial tensile loading were in agreement with experimental values, with differences of about 1–3%. Passive elasticity of muscle is simulated in the present research in order to provide the computation model as a benchmark in further development into the active contraction and the viscoelastic behavior. Additionally, it provides a modeling basis for patient-specific studies under varied pathological conditions. Full article

Directional long-borehole hydraulic fracturing is an important technique for controlling rockbursts induced by hard roofs. Its effectiveness depends primarily on whether fracturing-induced damage can modify the roof-bearing structure and thereby regulate stress concentration and elastic strain energy accumulation in the coal-rock mass ahead of the working face. However, existing numerical simulations commonly rely on predefined weakened zones or empirical parameter reduction, which makes it difficult to represent the spatial heterogeneity and mechanical evolution of rock damage during field hydraulic fracturing. Taking the 2803 goaf-side working face in Hetaoyu Coal Mine as the engineering background, this study proposes a microseismic-data-driven method for characterizing hydraulic fracturing-induced damage and incorporates it into a FLAC3D finite-difference model. The stress field, elastic strain energy field, and damage distribution ahead of the working face are compared under non-fractured and hydraulically fractured conditions. In the proposed method, the energy of fracturing-induced microseismic events is converted into the Benioff strain of numerical zones according to the attenuation law of microseismic wave propagation, and the corresponding rock damage variable is then calculated using a Weibull damage model. The fracturing-damaged rock mass is further represented by weakening the elastic modulus, cohesion, and friction angle, together with the stochastic generation of strongly damaged zones. The results show that, without hydraulic fracturing, the hard roof maintains a strong, continuous bearing capacity, resulting in a continuous lateral abutment stress concentration zone and a high elastic strain energy accumulation zone ahead of the working face and near the goaf-side boundary. After hydraulic fracturing, a patchy and locally connected high-damage weakening zone forms in the target roof strata. This damaged zone cuts the original continuous load-transfer structure through which the hard roof concentrates load toward the goaf side, reduces the extent of high-stress and high-energy zones in the coal seam, and induces an asymmetric adjustment of the dominant mining-induced energy release zone from the goaf side toward the solid-coal side. These simulation results agree well with the field observation that microseismic activity is mainly concentrated near the roadway on the solid-coal side. The study indicates that the rockburst-control mechanism of directional long-borehole hydraulic fracturing is not limited to simple overall stress dissipation. A key finding is that the fracturing-induced heterogeneous damage zone effectively interrupts the continuous load-transfer and energy-storage paths on the goaf side. This induces an asymmetric spatial redistribution of the mining-induced energy field from the goaf side toward the solid-coal side, thereby mitigating the high static-load and high-energy-storage state ahead of the working face. Full article

Accurate prediction of fatigue performance in Ni-based superalloys is hindered by scarce data and poor generalization of conventional machine learning. This study proposes a framework combining dynamic ensemble learning with transfer learning. A tensile prediction model using five base regressors (SVR, RFR, DTR, XGB, MLP) on 1025 tensile samples is first built. A dynamic weighted error feedback ensemble algorithm (DWELA) adjusts base model weights in real-time based on validation errors, improving tensile R² from 0.90 (best single model) to 0.95. To transfer knowledge to fatigue prediction, a feature alignment transfer learning (FATL) strategy aligns shared features (composition and heat treatment) between source (tensile) and target (fatigue) domains while fine-tuning domain-specific strain features, adapting effectively to a limited fatigue dataset of 622 samples. The resulting ETFPM model evaluated on five independent samples achieves R² of 0.93 (fatigue stress) and 0.81 (fatigue life), outperforming the best fatigue-trained single model (SVR: R² = 0.89 and 0.72). Twenty candidate alloys are predicted for screening. The method offers a practical route for fatigue prediction under data-limited conditions. The main novelties are: (i) DWELA’s real-time error-driven weight adaptation with hard constraints and early stopping, which improves tensile R² from 0.90 (best single model) to 0.95; and (ii) FATL’s explicit separation of frozen shared features and trainable exclusive features, enabling accurate fatigue prediction (R² = 0.93 for FS, 0.81 for FL) using only 622 fatigue samples. However, the independent validation is limited to five samples, and the datasets are compiled from the literature with potential heterogeneity in testing protocols and imputation bias for missing values. Further experimental validation is required to confirm broader applicability. Full article