Search Results (4,910)

Background: Implant material may influence interfragmentary mechanics in medial malleolar (MM) fracture fixation. This study aimed to compare stainless steel, titanium, magnesium, and PLGA screws under identical conditions using finite element analysis (FEA). Methods: A CT-based ankle model with a unilateral oblique MM fracture (θ = 60° to the medial tibial plafond) was fixed with two parallel M4 × 35 mm screws placed perpendicular to the fracture plane (inter-axial distance 13 mm). Contacts were defined as nonlinear frictional, and each screw was assigned a pretension force of 2.5 N. Static single-leg stance was simulated with physiologic tibia/fibula load sharing. Four scenarios differed only by screw material. Primary outputs were interfragmentary micromotion (maximum sliding and gap). Secondary measures included fracture interface contact/frictional stresses, screw/bone von Mises stress, global construct displacement, and average tibiotalar cartilage contact pressure. Results: Interfragmentary micromotion increased as screw stiffness decreased. Maximum sliding was 32.2–33.8 µm with stainless steel/titanium, 40.4 µm with magnesium, and 65.0 µm with PLGA; corresponding gaps were 31.2–32.0 µm with stainless steel and titanium, 31.2 µm with magnesium, and 54.1 µm with PLGA, respectively. Interface stresses followed the same pattern: contact pressure (3.18–3.24 MPa for stainless steel/titanium/magnesium vs. 4.29 MPa for PLGA); frictional stress (1.46–1.49 MPa vs. 1.98 MPa). Peak screw von Mises stress was highest in stainless steel (104.1 MPa), then titanium (73.4 MPa), magnesium (47.4 MPa), and PLGA (17.9 MPa). Global axial displacement (0.26–0.27 mm) and average tibiotalar cartilage contact pressure (0.73–0.75 MPa) were essentially unchanged across materials. All conditions remained below commonly cited thresholds for primary bone healing (gap < 100 µm); however, PLGA exhibited a reduced safety margin. Conclusions: Under identical geometry and loading conditions, titanium and stainless steel yielded the most favorable interfragmentary mechanics for oblique MM fixation; magnesium showed intermediate performane, and PLGA produced substantially greater micromotion and interface stresses. These findings support the use of metallic screws when maximal initial stability is required and suggest that magnesium may be a selective alternative when reducing secondary implant removal is prioritized. Full article

Root exudates represent a critical belowground carbon flux; however, direct field-based quantification of these rates on intact mangrove roots remains limited due to methodological challenges. Here, we present, to our knowledge, the first in situ evaluation of root exudation rates in a subtropical Bruguiera gymnorhiza forest in Japan, employing a modified cuvette method specifically designed for field measurements on intact root systems. The net root exudation rates measured in artificial seawater at depths of 0–60 cm ranged from 0.01 to 0.97 mg C g⁻¹ h⁻¹, with a mean of 0.22 mg C g⁻¹ h⁻¹. Although this mean rate was comparable to values reported for tropical terrestrial forests, the spatiotemporal variation exhibited variable site-specific patterns. At the midstream site, exudation rates were closely coupled with fine root biomass under nitrogen-limited conditions and peaked during summer. In contrast, the upstream site exhibited unusually high exudation rates during winter, even in deep soil layers. Furthermore, contrary to patterns typically observed in terrestrial forests, exudation rates showed positive correlations with root C:N ratios and proton efflux. These findings suggest that root exudation in mangroves is regulated by complex interactions among site-specific hydrological regimes and stress-adaptation mechanisms, particularly salinity tolerance and nutrient acquisition, rather than by simple growth trade-offs. When integrated over a depth of 0–60 cm, the estimated annual root exudate carbon flux was approximately 0.4 kg C m⁻² yr⁻¹. This likely represents a conservative lower-bound estimate because fine root systems extend well below this depth in mangrove forests. Our results strongly suggest that root exudates constitute an important, previously under-recognized component of the “missing carbon” in mangrove ecosystems and underscore the need to explicitly incorporate this flux into blue carbon models to more accurately evaluate mangrove carbon sequestration capacity. Full article

A low-permeability, high salinity reservoir entered the high-water-cut and high recovery degree stage in the middle and late stages of development, and it is difficult to tap the potential of water flooding. The overall water flooding recovery of the developed low-permeability reservoir is low, and the produced water has high oil content, many granular impurities, and high inorganic salt content. The polymer–surfactant binary system was studied according to the reservoir conditions. The polymer acrylic acid/polyacrylamide/2-acryloylamino-2-methyl-1-propanesulfonic acid was selected by viscosity measurement. The viscosity stability of the polymer and the effect of the flooding system were evaluated, and the salt-tolerant surfactant sulfonated betaine + amides and coco composite system were screened, and the viscosity, interfacial tension, and displacement effect were evaluated. Finally, the polymer–surfactant binary flooding system was formed. The system has good compatibility, the interfacial tension can still be reduced to 10⁻³ mN/m at 40 °C and 23,800 mg/L, and the viscosity of the polymer solution increased by 5.8% upon addition of the surfactant. The composite system can improve the oil displacement efficiency by 21.19%. The results of a parallel core displacement experiment with a 3.91 permeability ratio show that the oil displacement efficiency can be improved by 19.96%. The system has good performance in low-permeability oilfields and can effectively displace crude oil, which is of great significance for the displacement of low-permeability heterogeneous reservoirs. Full article

Owing to its ability to promote early recovery, platelet-rich plasma (PRP) is a popular regenerative therapy for treating sports injuries. However, its scientific basis has not yet been fully established. To bridge this gap, we focused on systemic antioxidant capacity, which suppresses exacerbated inflammation. Plasma total antioxidant capacity (TAC) in male professional soccer athletes (n = 30) was assessed alongside body composition measurements and compared with that of non-athletes (n = 31). Metabolic and inflammatory conditions were examined using erythrocyte sedimentation rate and plasma lactate, glucose, and protein levels. TAC levels were similar in both groups. Moderate correlations were observed between TAC and body fat percentage, skeletal muscle percentage, and basal metabolic rate in the control group, but not in the pro-athlete group, which exhibited superior body composition indices. These findings suggest that TAC levels may not directly influence PRP therapy in athletes. However, when compared with TAC levels calculated using correlations obtained in controls, the measured TAC levels (329.3 mM) were substantially higher than the compensated levels (62.5 mM for basal metabolic rate) in pro-athletes. This analytical approach indicates that TAC may theoretically be elevated to higher levels in pro-athletes when evaluated using non-athlete-based scales. Full article

This study investigated the effects of 6 weeks of plyometric training (PT) performed on soft (unstable) and hard (stable) surfaces compared with conventional training on the balance, explosive power, and muscle strength of adolescent female basketball players. The participants were randomly assigned to three groups: soft-surface PT (n = 14), hard-surface PT (n = 14), and conventional training (n = 14). Performance outcomes included 30 m sprint time, vertical jump height, plantar flexion and dorsiflexion maximal voluntary isometric contraction (MVIC) torque, Y-balance dynamic balance, and center of pressure-based static balance. Ground reaction forces, MVIC torques, and balance parameters were measured using high-precision force sensors to ensure accurate quantification of biomechanical performance. Statistical analyses were performed using two-way repeated-measures ANOVA with post hoc comparisons to evaluate group × time interaction effects across all outcome variables. Results demonstrated that soft- and hard-surface PT significantly improved sprint performance, vertical jump height, and plantar flexion MVIC torque compared with conventional training, while dorsiflexion MVIC increased similarly across all the groups. Notably, soft-surface training elicited greater enhancements in vertical jump height, dynamic balance (posteromedial and posterolateral directions), and static balance under single- and double-leg eyes-closed conditions. The findings suggest that PT on an unstable surface provides unique advantages in optimizing neuromuscular control and postural stability beyond those achieved with stable-surface or conventional training. Thus, soft-surface PT may serve as an effective adjunct to traditional conditioning programs, enhancing sport-specific explosive power and balance. These results provide practical guidance for designing evidence-based and individualized training interventions to improve performance and reduce injury risk among adolescent female basketball athletes. Full article

Biosurfactants produced by halophilic bacteria are gaining attention as eco-friendly and biocompatible alternatives to synthetic surfactants due to their high surface activity, stability under extreme conditions, and intrinsic antimicrobial properties. These amphiphilic biomolecules hold great promise for bioremediation, biomedical, and pharmaceutical applications. In this study, moderately halophilic bacteria capable of biosurfactant production were isolated from saline mud collected at the Burgas solar salterns (Bulgaria). The halophilic microbiota was enriched in Bushnell–Haas (BH) medium containing 10% NaCl amended with different carbon sources. Primary screening in BH liquid medium evaluated the isolates’ ability to degrade n-hexadecane while at the same time producing biosurfactants. Thirty halophilic bacterial strains were isolated on BH agar plates supplemented with 2% n-hexadecane, 2% olive oil, or 2% glycerol. Four isolates—BS7OL, BS8OL, BS9GL, and BS10HD—with strong emulsifying activity (E₂₄ = 56%) and reduced surface tension in the range of 27.3–45 mN/m were derived after 7 days of batch fermentation. Strain BS10HD was chosen as the most potent biosurfactant producer. Its phylogenetic affiliation was determined by 16S rRNA gene sequence analysis; according to the nucleotide sequence, it was assigned to Halomonas ventosae. The extract material was analysed by thin-layer chromatography (TLC) and Fourier transform infrared spectroscopy (FTIR). Upon spraying the TLC plate with ninhydrin reagent, the appearance of a pink spot indicated the presence of amine functional groups. FTIR analysis showed characteristic peaks for both lipid and peptide functional groups. Based on the observed physicochemical properties and analytical data, it can be suggested that the biosurfactant produced by Halomonas ventosae BS10HD is a lipopeptide compound. Full article

Agricultural production residues are an easily accessible raw material for energy recovery in a circular economy. Therefore, the possibility of biogas production from herb processing waste, namely common thyme (Thymus vulgaris L.), peppermint (Mentha × piperita L.), curled mint (Mentha crispa L.), and currants (woody stems and leaves), was investigated. In this study, the evaluation of the natural biodegradability of plant waste under conditions typical for an agricultural biogas plant was consciously carried out without the application of pre-treatment processes (shredding, steam hydrolysis, chemical treatment) to facilitate the methane fermentation process. The average values of biogas production efficiency ranged from 75 to 320 m³/mg DM for herb species and from 152 to 209 m³/mg DM for currant varieties under normal conditions. As part of laboratory tests, the elemental composition, i.e., C, H, N, S, O, was determined. Moreover, the analysis showed the energy potential of the tested waste in thermochemical processes (combustion). Garden thyme residues have particularly high energy potential, as indicated by the high calorific value, low nitrogen and sulfur content, and low ash content. Full article

Characterization of propeller blade vibrations is essential to ensure aerodynamic performance, minimize noise emissions, and maintain structural integrity in aerospace and unmanned aerial vehicle applications. Conventional high-fidelity finite-element and fluid–structure simulations yield precise modal predictions but incur prohibitive computational costs, limiting rapid design exploration. This paper introduces a data-driven surrogate modeling framework based on a feedforward neural network to predict natural vibration frequencies of propeller blades with high accuracy and a dramatically reduced runtime. A dataset of 1364 airfoil geometries was parameterized, meshed, and analyzed in ANSYS 2024 R2 across a range of rotational speeds and boundary conditions to generate modal responses. A TensorFlow/Keras model was trained and optimized via randomized search cross-validation over network depth, neuron counts, learning rate, batch size, and optimizer selection. The resulting surrogate achieves $R^2>0.90$ and $NRMSE<0.08$ for the second and higher-order modes, while reducing prediction time by several orders of magnitude compared to full finite-element workflows. The proposed approach seamlessly integrates with CAD/CAE pipelines and supports rapid, iterative optimization and real-time decision support in propeller design. Full article

The aim of the experiment was to assess the effects of municipal sewage sludge, mushroom substrate, and hydrogel on the quality of energy grass species and their biomass yield. The experiment was conducted in the climatic conditions of central-eastern Poland between 2020 and 2022. Two perennial grass species were used: Miscanthus giganteus (giant miscanthus) M 19 and Panicum virgatum L. (rod millet) var. Northwind. Sewage sludge and mushroom substrate doses, each corresponding to 170 kg N·ha⁻¹, were applied in the spring of the first year. The experiment was established on microplots with four replications. Each year, biomass was harvested in January, and the yield of fresh and dry matter was determined. Then plant material was adequately prepared, and the total content of P, Ca, and Mg was measured with the ICP-OES method. The application of hydrogel resulted in a significant increase in the yield of each grass species: giant miscanthus by 11.87% and rod millet by 8.28%. Organic waste applied in combination with hydrogel increased the yield of energy plants and improved their chemical composition. Full article

Glucocorticoids are widely applied intra-articularly to alleviate inflammation and pain in osteoarthritis (OA). However, repeated administration and high local concentrations can lead to crystal deposition on the cartilage surface, contributing to chondrocyte damage and extracellular matrix (ECM) degradation, potentially accelerating OA progression. Calcium-dependent mechanosensors play a critical role in mediating catabolic responses in chondrocytes, but it remains unclear whether glucocorticoids affect chondrocyte mechanosensitivity or biomechanical properties. This in vitro study examined the dose-dependent effects of triamcinolone acetonide (TA) on chondrocyte biomechanics and mechanosensitivity. Primary human chondrocytes (N = 23) were cultured for one week with TA (2 µM–2 mM) or control medium. Cytoskeletal organization was visualized by F-actin staining (N = 6), and cellular elasticity (N = 5) was quantified via atomic force microscopy (AFM). Mechanotransduction was analyzed by Ca²⁺ imaging (Fluo-4 AM) upon AFM-based indentation (500 nN). Expression of matrix-related and mechanosensitive genes (N = 9) was assessed by qPCR. TA exposure induced a concentration-dependent reorganization of the F-actin cytoskeleton, pronounced at 0.2 mM, accompanied by a significant increase in the elastic modulus (p < 0.001). TA further augmented Ca²⁺ fluorescence intensity under basal conditions and during mechanical stimulation. Blocking cationic mechanosensitive channels with GsMtx4 (N = 3) markedly reduced the TA-evoked Ca²⁺ influx (p < 0.0001). Significant reduction in MMP1 was observed on the transcriptional level (N = 9) after TA-treatment (p < 0.05). In summary, TA enhances chondrocyte stiffness through cytoskeletal condensation and amplifies Ca²⁺-dependent mechanotransduction but reduces MMP1 expression, indicating a dual biomechanical response of chondrocytes to OA under exposure of potent corticosteroid. Full article

Micro-minerals are essential for fish, but traditional inorganic micro-minerals (IMM) have low bioavailability. This study evaluated coated inorganic micro-minerals (CIMM) in juvenile American eels under commercial recirculating aquaculture system (RAS) conditions. Three experimental groups (n = 3 tanks per group, stocking density: 138 fish/m³) were fed basal diets supplemented for 56 days with: 1000 mg/kg IMM (IMM group, providing Cu 7, Fe 200, Mn 30, Zn 70, I 1.6, Se 0.4, and Co 1.2 mg/kg diet), 1000 mg/kg CIMM (CIMM group I), or 500 mg/kg CIMM (CIMM group II). Compared to the IMM group, the CIMM group I demonstrated significantly enhanced growth performance, with the specific growth rate increasing by approximately 31.14%, higher whole-body content and retention of minerals (Ca, P, Cu, Fe, Mn, Zn), and superior intestinal health, as reflected by significantly increased activities of digestive enzymes (amylase and lipase), enhanced antioxidant capacity (elevated SOD and CAT, reduced MDA), and improved morphology (villi length and muscular thickness), an altered intestinal microbiota (increased relative abundance of Firmicutes and reduced relative abundance of Proteobacteria), and significant metabolomic alterations in purine metabolism and linoleic acid metabolism. The CIMM group II maintained growth performance, with no significant difference in WGR and SGR compared to the IMM group, while still showing significant improvements in feed intake and mineral retention (P, Cu, Fe, Zn), and antioxidant capacity. Collectively, this study not only confirms the efficacy of CIMM in commercial RAS but also reveals that the supplementation level previously shown to be effective in the laboratory (50% CIMM) is insufficient under commercial farming conditions, implying that the dietary micro-mineral requirements for juvenile American eels in commercial RAS may be higher than those established in laboratory settings. Full article

Background: Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or depression both frequently report debilitating exhaustion, yet the two conditions differ in their etiological and diagnostic clarity, and clinical management. This study aimed to examine differences in the use and perceived helpfulness of a broad range of conventional treatments and complementary interventions, including nutritional approaches, between patients with ME/CFS and depression. Methods: A cross-sectional online survey was conducted in 2024. A total of 819 participants self-identified as having either ME/CFS (n = 576) or depression (n = 243). Participants (80% female) reported their use and perceived helpfulness of 52 treatments and interventions, encompassing behavioral therapies, medications, and dietary supplements. Group differences were examined using multivariate analyses of variance and covariance (MANOVA/MANCOVA). Open-ended responses were analyzed descriptively using thematic grouping and frequency counts. Results: Participants with depression most commonly reported the use of psychotherapy (M = 2.49, SD = 1.00) and antidepressant medication (M = 2.44, SD = 2.30), and they rated fewer interventions as helpful compared to participants with ME/CFS. In contrast, participants with ME/CFS reported a significantly broader engagement with diverse intervention modalities, particularly pacing (M = 2.73, SD = 0.80) and dietary supplements (M = 2.43, SD = 1.09), and perceived many of them as helpful. Group differences remained significant after controlling for age, gender, and whether treatment was medically recommended. Supplements targeting energy metabolism (e.g., CoQ10, NADH) were especially favored among ME/CFS participants. Conclusions: Findings suggest that participants with ME/CFS tend to adopt an exploratory and expansive intervention approach, potentially reflecting the lack of standardized guidelines and limited effectiveness of available treatment options. Participants with depression, in contrast, appeared to follow more guideline-concordant, evidence-based treatment pathways. Taken together, the findings point to a need for further development and evaluation of empirically supported, patient-centered treatment and intervention strategies for ME/CFS and suggest differences in clinical care structures between ME/CFS and depression. Full article

Within the domain of intelligent picking robotics, fruit recognition and positioning are essential. Challenging conditions such as varying light, occlusion, and limited edge-computing power compromise fruit maturity detection. To tackle these issues, this paper proposes a lightweight algorithm YOLO-ELS based on YOLOv8n. Specifically, we reconstruct the backbone by replacing the bottlenecks in the C2f structure with Edge-Information-Enhanced Modules (EIEM) to prioritize morphological cues and filter background redundancy. Furthermore, a Large Separable Kernel Attention (LSKA) mechanism is integrated into the SPPF layer to expand the effective receptive field for multi-scale targets. To mitigate occlusion-induced errors, a Spatially Enhanced Attention Module (SEAM) is incorporated into the decoupled detection head to enhance feature responses in obscured regions. Finally, the Inner-GIoU loss is adopted to refine bounding box regression and accelerate convergence. Experimental results demonstrate that compared to the YOLOv8n baseline, the proposed YOLO-ELS achieves a 14.8% reduction in GFLOPs and a 2.3% decrease in parameters, while attaining a precision, recall, and mAP@50% of 92.7%, 83.9%, and 92.0%, respectively. When compared with mainstream models such as DETR, Faster-RCNN, SSD, TOOD, YOLOv5s, and YOLO11n, the mAP@50% is improved by 7.0%, 4.7%, 11.4%, 8.6%, 3.1%, and 3.2%. Deployment tests on the NVIDIA Jetson Orin Nano Super edge platform yield an inference latency of 25.2 ms and a detection speed of 28.2 FPS, successfully meeting the real-time operational requirements of automated harvesting systems. These findings confirm that YOLO-ELS effectively balances high detection accuracy with lightweight architecture, providing a robust technical foundation for intelligent fruit picking in resource-constrained greenhouse environments. Full article

Objective gait assessment is essential for post-stroke rehabilitation monitoring, yet optical motion capture systems remain inaccessible to most clinical settings due to cost and infrastructure constraints. This study assessed the validity of the REEV SENSE IMU for measuring spatiotemporal gait parameters in post-stroke individuals and evaluated assistive device effects on measurement accuracy. Twenty chronic post-stroke participants were enrolled, and fourteen completed the study (ten without an assistive device, four using a cane) after applying pre-defined exclusion criteria (walking speed <0.28 m/s, n = 6). Participants walked at self-selected speed while simultaneously being recorded by REEV SENSE IMUs and optical motion capture. Spatiotemporal parameters from matched heel strikes were compared using intraclass correlation coefficients (ICC), mean relative error (MRE), and Bland–Altman analysis. Temporal parameters demonstrated excellent reliability: contact time (ICC 0.96–0.99, MRE 2.77–5.45%), stride duration (ICC 0.95–0.99, MRE 2.57–2.62%), and cadence (ICC 0.98–0.99, MRE 1.80–1.93%). Spatial parameters showed greater variability, with stride length degrading substantially in slow-walking conditions (Cane group: ICC 0.76, MRE 8.60%). REEV SENSE provides reliable temporal parameter measurement comparable to commercial systems, positioning it as a practical tool for clinical gait monitoring in post-stroke rehabilitation. However, spatial parameter accuracy requires cautious interpretation in slow-walking regimes, necessitating independent validation when clinical decisions depend on precise stride length estimates. Full article

Understanding how contextual variables shape differences in match demands in youth football is essential for optimising performance and player development. Objective: This study aimed to compare physical and competitive performance according to playing position, match location, match result, and opponent quality in the physical and competitive performance of U21 football players from a professional Chilean club. Methods: Twenty male U21 players (19.2 ± 1.2 years) were monitored during 11 official matches using 10 Hz GPS devices (WIMU Pro™) and post-match Rating of Perceived Exertion (RPE). Variables included total distance (TD), high-speed running (HSR > 20 km/h), metres per minute (MM), accelerations/decelerations (N°AC/N°DC > 3 m·s⁻²), player load (PL), and peak velocity (PV). Contextual variables were classified by playing position, home/away, win/loss, and opponent quality (higher vs. lower rank). Results: Significant between-group differences were found across all contextual factors (p < 0.05). Midfielders (MFs) covered greater TD and reported higher RPE, while full-backs (FBs) and wingers (WGs) reached higher HSR and PV. Away and lost matches showed greater RPE, PL, and N°AC/N°DC, alongside more goals conceded. Facing higher-ranked opponents increased RPE and HSR but reduced explosive actions. Conclusions: Physical performance in U21 football is strongly modulated by contextual factors. Coaches should adjust training load and tactical strategies according to match conditions and positional roles to optimise adaptation and competitive readiness in developmental categories. Full article