Search Results (19,958)

Over 30,000 hip hemiarthroplasty (HA) operations are performed every year across England and Wales to treat fractured necks of the femur. HA reduces surgical and recovery time with lower complication rates; however, it may cause acetabular deterioration, which can lead to revision surgery and possible conversion to total hip arthroplasty (THA). This study assessed hip hemiarthroplasty under gait-representative loading in an anatomical hip simulator. Paired natural acetabula were tested against a CoCr femoral head with radial clearance (RC) of −0.75 mm (head larger than natural) and positive RCs of <0.6 mm (small), 2 mm–4 mm (large), and >4 mm (extra-large). Cartilage surface deterioration was quantified via photogrammetry. Cartilage surface changes were observed in all hemiarthroplasty groups, while no changes were observed in the control group. No statistically significant between-groups in the affected area were detected (Kruskal–Wallis, p > 0.29). The negative RC group showed statistically significant progressive worsening over time (Friedman: (χ²(2) = 8.00, p = 0.018). Groups differed in damage onset, location, intensity, and presence of delamination. Samples with negative RC (oversized head) produce earlier and progressive cartilage changes. The results highlight the importance of carefully measuring the native head diameter and choosing a femoral head size when performing HA. Full article

Cr(VI) has become an urgent environmental concern due to its high toxicity. Adsorption is regarded as an effective technique for Cr(VI) removal, and high-performance adsorbents remain in great demand. In this study, waste-derived magnetic biochar (Fe⁰-Fe₃O₄ MB) was synthesized via synchronous pyrolysis combined with liquid-phase reduction, using Chinese medicinal residue as biomass feedstock and iron-based sludge as the sole iron source instead of traditional chemical agents. Mössbauer spectroscopy (MS) results confirmed the feasibility and high efficiency of synthesizing Fe⁰ using iron sludge as the iron source; meanwhile, in situ generated Fe₃O₄ and biochar effectively restrained particle aggregation and the surface passivation of Fe⁰. Cr(VI) adsorption fitted well with pseudo-second-order kinetics and Langmuir isotherm models, which suggests a predominant monolayer chemisorption process. The Fe⁰-Fe₃O₄ MB possessed excellent superparamagnetism, with a saturation magnetization of 66.74 emu/g. Rapid Cr(VI) adsorption was achieved within 30 min at pH 2 and 35 °C, with a maximum adsorption capacity of 128.36 mg/g. The main adsorption mechanisms may involve multiple pathways, including physical adsorption, electrostatic attraction, chemical reduction, and surface complexation. This study provides a feasible strategy for solid waste resource utilization and the fabrication of stabilized functional zero-valent iron materials, realizing the efficient adsorption treatment of Cr(VI)-containing wastewater. Full article

The common bed bug (Cimex lectularius L.) is an obligate blood-feeding insect that spreads easily through human activity. Catnip (Nepeta cataria L.) oil has emerged as a promising natural repellent for bed bugs, but previous studies have been limited to laboratory conditions. In this study, we assessed the effectiveness of a catnip-based formulation (20% catnip CCC oil: 10% catnip oil cultivar CR9, 5% carvacrol, 5% citronellol) applied to fabric against bed bugs using simulated field tests, a human finger stimulus test, and field trials. N-Diethyl-meta-toluamide (DEET) was included as a benchmark in the simulated field test. In these tests, both 20% catnip CCC oil and 20% DEET achieved > 94% repellency within 24 h, with comparable performance after 2–3 d of aging. After 5 d, 20% catnip CCC oil showed significantly reduced repellency compared to DEET. In the human finger stimulus test, 20% catnip CCC oil remained effective for up to 6 d, whereas in infested apartments, significant repellency lasted only one day. These findings suggest that 20% catnip CCC oil applied to fabric can provide short-term protection against bed bug introductions under natural conditions. Future work should explore optimized barrier dimensions and slow-release formulations to extend efficacy. Full article

Background/Objectives: Decreases in skeletal muscle mass affect the efficacy of and tumor response to various therapies for hepatocellular carcinoma (HCC). This study aimed to investigate the relationship between changes in skeletal muscle mass during TACE-based combination therapy and tumor response and prognosis. Methods: This retrospective study analyzed 306 patients with unresectable HCC, divided into four groups according to the treatment received: TACE alone (n = 133), TACE plus targeted and immunotherapy combination (TACE + T + I, n = 68), TACE plus immunotherapy (TACE + I, n = 52), and TACE plus targeted therapy (TACE + T, n = 53). Skeletal muscle mass was assessed at the third lumbar vertebral level (L3) before treatment and at six months post-treatment using computed tomography (CT) scans. Patients were stratified based on changes in skeletal muscle index (SMI) values. Kaplan–Meier and Cox proportional hazards models were used to compare overall survival (OS) among groups classified by changes in SMI, while tumor response was assessed with univariate and multivariate analyses, using logistic regression analysis. Result: A total of 306 patients with unresectable HCC were included in this study. The median OS was 17.0 (0.9–83.0) months in the decreased-SMI group compared with 35.0 (2.0–113.0) months in the non-decreased-SMI group. The overall response rate (CR + PR) was 34.7% in the decreased-SMI group and 53.8% in the non-decreased group. Among different treatment regimens, significant differences in Kaplan–Meier survival curves were observed between the TACE and TACE + T + I groups. In multivariate analysis, decreased SMI remained an independent predictor of poor OS and tumor non-response, whereas a low-SMI pre-treatment was not an independent prognostic factor. Additionally, inadequate nutritional status and compromised liver function were associated with a greater decrease in SMI during comprehensive treatment. Conclusions: A decline in skeletal muscle index (SMI) among patients with unresectable hepatocellular carcinoma (HCC) undergoing TACE-based comprehensive treatment is associated with poor prognosis and unfavorable tumor response and is further linked to deteriorating nutritional status and impaired liver function. Monitoring SMI provides an effective approach for assessing overall patient condition and predicting clinical outcomes. Full article

Background/Objectives: Acute pulmonary embolism (PE) is a major cause of cardiovascular mortality, with prognosis influenced by hemodynamic status, comorbidities, and biomarker profiles. Although several laboratory markers have demonstrated prognostic relevance in PE, it remains unclear whether their predictive performance differs in patients with active malignancy. This study aimed to identify laboratory predictors of in-hospital mortality in acute PE and evaluate the modifying effect of malignancy on biomarker-based prognostic stratification. Methods: This retrospective multicenter cohort study included 2803 consecutive patients with confirmed acute PE enrolled in the Regional Pulmonary Embolism Registry (REPER) between January 2015 and April 2026. Univariate and multivariable logistic regression analyses were performed to identify predictors of in-hospital mortality in the overall cohort and subgroups stratified by malignancy status. Interaction analyses were used to formally assess effect modification by malignancy. Results: Active malignancy was present in 14.02% of patients, and overall in-hospital mortality was 11.10%. Multivariable analysis identified malignancy, CRP, glucose, creatinine clearance (CrCl), platelet count, and ESC risk category as independent predictors of in-hospital mortality. In-hospital mortality was significantly higher in patients with malignancy compared with those without (16.54% vs. 10.21%, p < 0.001). In the malignant subgroup, CRP and glucose remained independent predictors, whereas in non-malignant patients, CRP, glucose, CrCl, and ESC risk category were independently associated with outcome. Significant interactions between malignancy status and CrCl, age, glucose, and total leukocyte count suggest that the prognostic contribution of these variables may differ according to cancer status. Conclusions: Active malignancy is an independent predictor of in-hospital mortality in acute PE and appears to be associated with a more severe presentation. Our findings suggest that malignancy may also modify the prognostic performance of certain biomarkers. These observations suggest that conventional risk stratification tools may require cautious, malignancy-aware interpretation and that prospective studies validating malignancy-adapted prognostic frameworks are warranted. Full article

In the present work, four grades of austenitic stainless steels, namely AISI 321, AISI 316Ti, AISI 309, and AISI 310S, are investigated in terms of electrochemical hydrogenation effect on their room-temperature impact toughness. All the materials were studied in their as-received (AR), i.e., industrially manufactured, material condition. LOM and SEM microstructural analyses combined with phase XRD and EBSD phase analyses revealed in all steels the polygonal-grain austenitic matrix and varying minor amounts of elongated δ-ferrite grains. Moreover, the metastable AISI 321 and AISI 316Ti steels exhibited noticeable occurrence (16% and 10%, respectively) of the BCC-structured phases (i.e., the strain-induced α′-martensite and non-equilibrium δ-ferrite) and little occurrence of primary TiN nitrides (below 1%). The AISI 321 and AISI 316Ti steels exhibited average amounts of 2.95% and 6.32% of δ-ferrite, respectively. The stable AISI 309 steel exhibited the occurrence of intergranular (Cr,Fe)₂₃(C,N)₆ precipitates (below 3%), indicative of prolonged (slow) cooling from the warm working temperature during the material manufacturing. The individual steel grades exhibited variable values of hardness and impact toughness depending strongly on their solid solution alloying and the amounts of individual minor phases in their microstructures. The AISI 316Ti steel exhibited the highest average hardness (273 HV) and lowest impact toughness (160 J/cm²) due to Mo-alloying and having the highest amount of δ-ferrite. The AISI 310S steel showed the highest impact toughness (210 J/cm²) and the second highest hardness (245 HV) thanks to having the most stable austenitic microstructure with the highest Ni- and Cr-alloying. The AISI 321 and AISI 309 steels show similarly low hardness (195 HV vs. 196 HV) and medium values of impact toughness (202 J/cm² vs. 193 J/cm²). More importantly, all the steels under investigation exhibited detectable hydrogen-induced toughening effects, indicated by the negative HEI values. The metastable steels showed the lowest toughening effects (HEI: −2.0% and −3.8% for AISI 321 and AISI 316Ti, respectively), likely due to the adverse effect of α′-martensite. In contrast, the stable steels exhibited much higher toughening (HEI: −5.2% and −7.6% for AISI 309 and AISI 310S, respectively). Microstructural observations indicated that such toughening behavior might be related to the hydrogen-enhanced deformation banding and hydrogen-enhanced deformation twinning mechanisms, dividing the grains into smaller deformation zones, increasing the overall dissipation of deformation energy and consequently the materials’ impact toughness. Full article

Defect engineering of anatase TiO₂ nanosheets by hydrogen reduction is a compelling strategy to boost visible light photocatalytic Cr(VI) reduction, a process of vital importance for detoxifying highly toxic and carcinogenic Cr(VI) pollutants. However, the necessary high-temperature hydrogen treatment invariably induces morphological collapse, negating the structural merits of the two-dimensional nanosheets. Herein, we propose an ethylenediamine reflux protection strategy combined with hydrogen reduction to fabricate defect-rich TiO₂ nanosheets (EN-TiO_2−x-NS) that preserve the original morphology. The resulting EN-TiO_2−x-NS retained the square nanosheet structure and (001) facets, while Ti³⁺ and oxygen vacancies were successfully introduced. The bandgap narrowed from 2.95 to 2.55 eV, leading to enhanced visible light absorption and charge separation efficiency. For photocatalytic Cr(VI) reduction under visible light, EN-TiO_2−x-NS achieved a removal rate of 97.3% within 20 min, with a rate constant 1.93 times higher than that of pristine TiO₂ nanosheets and 3.17 times higher than that of the directly hydrogenated sample. The catalyst also exhibited excellent cycling stability. This work demonstrates a synergistic strategy combining morphology preservation and defect engineering, providing a new approach for designing high-performance TiO₂-based photocatalysts. Full article

The growing demand for implant-supported rehabilitative prosthetic treatments has reinforced the need to optimize biomechanical performance, particularly regarding force distribution. This study aimed to evaluate the stress distribution generated by different configurations of full-arch implant-supported prostheses using three-dimensional finite element analysis. Two mandibular models were created using SolidWorks 2010 (SolidWorks Corp., Waltham, MA, USA) and Rhinoceros^® 3D 4.0 (NURBS Modeling for Windows, USA). Each model represented a mandible restored with a full-arch fixed prosthesis supported by external hex implants (4.0 × 13.0 mm; Master, Conexão Sistemas de Prótese, São Paulo, Brazil) placed in the interforaminal region, differing only in implant angulation. Model 1 included four implants positioned perpendicular to the alveolar ridge, whereas Model 2 represented the All-on-Four configuration with distal implants tilted at 30°. The prosthesis was modeled in acrylic resin with a NiCr metal framework. The geometries were exported to FEMAP 11.0 for mesh generation. Axial loading of 300 N was applied bilaterally (75 N per tooth), and oblique loading of 150 N was applied unilaterally (75 N per tooth) on the first premolars and first molars. Obtained using NEiNastran^® 9.2 showed that the tilted-implant model exhibited higher stress concentrations under both loading conditions. The All-on-Four configuration generated the highest stress levels, particularly around the distal implants. The null hypothesis of this study was that there would be no difference in stress distribution among full-arch implant-supported prostheses supported by straight implants and those rehabilitated according to the All-on-Four concept with tilted distal implants. Full article

Background: Healthcare-associated bloodstream infections remain a significant cause of morbidity and mortality in hospitalized children, particularly in intensive care settings. Carbapenem-resistant Gram-negative bacterial (CR-GNB) bloodstream infections and fungemia may present with overlapping clinical features. This can complicate empirical treatment decisions in resource-limited settings. This study evaluated baseline clinical and laboratory characteristics associated with CR-GNB bloodstream infections and fungemia among high-risk pediatric patients. Methods: This retrospective observational cohort study included pediatric patients aged 0–18 years who were evaluated at the time of clinical deterioration and blood culture collection for suspected healthcare-associated bloodstream infection before empirical antifungal therapy initiation for the index episode. Patients who subsequently received empirical antifungal therapy between May 2023 and September 2025 were retrospectively screened. Of the 240 screened patients, 103 met the inclusion criteria and were classified into CR-GNB (n = 56) and fungemia (n = 47) groups based on blood culture results. Clinical, laboratory, and microbiological data were analyzed using univariate and multivariable statistical methods. Results: Observed 90-day all-cause mortality was higher in the CR-GNB group than in the fungemia group (50.0% vs. 29.8%, p = 0.038). Central venous catheter use was more frequent (91.1% vs. 48.9%, p = 0.006), and platelet counts were lower (median: 120 × 10⁹/L vs. 259 × 10⁹/L, p = 0.011) in patients with CR-GNB bloodstream infections. In multivariable analysis, thrombocytopenia (OR: 4.22, 95% CI: 1.35–13.17; p = 0.013) and central venous catheter use (OR: 5.53, 95%: CI 1.89–16.26; p = 0.002) were independently associated with CR-GNB bloodstream infections. The model showed moderate discrimination (AUC = 0.786). Conclusion: In this selected high-risk cohort, thrombocytopenia and central venous catheter use were associated with CR-GNB bloodstream infections. Observed mortality was higher in the CR-GNB group, but this finding should be interpreted with caution as adjusted mortality analysis and standardized severity assessment were not performed. These findings are hypothesis-generating and require validation in larger prospective studies before guiding empirical treatment decisions. Full article

Groundwater is vital to subsurface ecosystems and to maintaining water supplies for human and environmental needs. Heavy metal pollution of water bodies poses a significant threat to environmental health and human well-being. In this paper, a detailed spatiotemporal analysis of heavy metal pollution at a network of 35 sampling sites is presented for the summer, autumn, and winter seasons. The water samples were analyzed based on the concentration (μg/L) of eight priority metals, such as Lead (Pb), Mercury (Hg), Cadmium (Cd), Arsenic (As), Chromium VI (Cr-VI), Copper (Cu), Zinc (Zn), as well as Iron (Fe). Measuring contamination levels, identifying space hotspots, and explaining seasonal variations were the key tasks. The results show that Fe, Zn, and Cu concentrations are consistently high across seasons, with mean values ranging from 234.3 to 253.2 µg/L (Fe), 163.2 to 175.6 µg/L (Zn), and 107.0 to 109.2 µg/L (Cu), indicating a widespread geogenic or diffuse source. The most significant seasonal deviation was observed in the fall when there were unusually high levels of Cd and Hg, with mean concentrations reaching 0.476 µg/L and 0.312 µg/L, respectively, suggesting a strong seasonal contamination event or mobilization process. The spatial analysis showed that the locations (e.g., L6, L8, L10, L28, L29) exhibited common hotspots for different metals, with maximum concentrations reaching up to 793.3 µg/L (Fe), 602.3 µg/L (Zn), and 508 µg/L (Cu). Principal Component Analysis (PCA) effectively separated seasonal trends and classified metals into anthropogenic (Pb, Cd, Hg, Cr (VI)) and geogenic/diffuse (Fe, Zn, Cu) groups. The health risk assessment indicated no significant non-carcinogenic risk, although children are more vulnerable, while arsenic levels in winter approached the upper acceptable carcinogenic limit (up to 1.1 × 10⁻⁴). Overall, the study highlights the importance of multi-seasonal monitoring by capturing temporally abrupt contamination events and provides a novel integrated framework that combines seasonal analysis, spatial hotspot identification, and multivariate techniques, distinguishing it from conventional single-season or non-integrated studies. Full article

With the growing potential correlation between chromium (Cr), molybdenum (Mo), and human health, public attention to these elements has increased markedly. In Beijing, the capital of China, research on the concentration levels of Cr and Mo is urgently needed. In recent years, soil geochemical surveys have been conducted in the Beijing region, with a scale of 1:100,000 in mountainous areas (yielding 8575 data points) and 1:50,000 in plain areas (yielding 29,551 data points). These surveys provide a robust dataset for elucidating the concentrations and distribution patterns of soil elements. In surface soil samples from Beijing (n = 38,126), the mean concentrations of Cr and Mo were 55.7 µg/g and 0.67 µg/g, respectively. Recently, scholars have proposed a 19-level fixed-value method for Mo concentrations. Based on this, the 19-level fixed-value method for Cr concentrations is proposed to facilitate cross-element comparisons. This method classifies the elemental concentrations from its detection limit to its cut-off grade of mineralization into 19 levels on 18 fixed values. With this method, the concentration levels of Cr and Mo in Beijing soils are both at the fifth level on their mean values, which belong to the background level. To compare the Cr and Mo concentrations in soils with other capital cities, statistical parameters of Cr from 20 capital cities and Mo from 11 capital cities were collected. The results show that the mean Cr concentration levels in the 20 cities range from 2 to 10, while the mean Mo concentration levels in the 11 cities range from 5 to 10. In these capital cities, the Cr level of Beijing is at the middle level, and the Mo level is at the low level, which indicates the cross-element comparison on the 19-level fixed-value method. Full article

Background: Parathyroid hormone (PTH) is mainly regulated by calcium, vitamin D, and renal function, but metabolic factors may also influence its levels. The uric acid/creatinine (UA/Cr) ratio reflects uric acid metabolism and renal handling. This study evaluated its association with elevated PTH in adults without known parathyroid disease. Methods: This retrospective cross-sectional study included 244 adults undergoing routine biochemical evaluation. The uric acid-to-creatinine ratio (UA/Cr) was calculated. Participants were categorized according to PTH levels (≤65 pg/mL vs. >65 pg/mL). Logistic regression analyses were performed to identify factors associated with elevated PTH levels. Results: A total of 244 individuals (mean age 40.6 ± 11.7 years; 70.9% female) were included in the analysis. Participants with elevated PTH levels had significantly higher UA/Cr ratios compared with those with normal PTH levels (8.93 ± 1.82 vs. 7.47 ± 1.79, p = 0.031). In univariate logistic regression analysis, UA/Cr was associated with elevated PTH (OR 1.15, 95% CI 1.01–1.32, p = 0.043). In multivariable logistic regression analysis adjusting for vitamin D, magnesium, phosphorus, corrected calcium, age, sex, body mass index, and the estimated glomerular filtration rate, the UA/Cr ratio remained significantly associated with elevated PTH levels (OR 1.41, 95% CI 1.036–1.66, p = 0.024). Conclusions: The UA/Cr ratio was associated with elevated PTH levels in adults without known parathyroid disease, independently of vitamin D status, mineral metabolism parameters, and renal function. These findings suggest that the UA/Cr ratio may help characterize a broader metabolic context associated with elevated PTH levels, rather than serving as a diagnostic marker. Further prospective studies are needed to clarify the clinical relevance and direction of this association. Full article

To address the ecological risks associated with highly mobile hexavalent chromium [Cr(VI)], woody biochar was functionalized with hydrogen peroxide (H₂O₂) to develop a dual-phase remediation material (H-BC) for aqueous and soil environments. Batch post-contact isotherm fitting yielded a Langmuir-fitted/extrapolated apparent retention capacity q_m of 77.44 mg/g at 328 K. This value reflects enhanced overall Cr(VI)-derived retention within the tested concentration range, rather than increased electrostatic affinity for chromate oxyanions. Empirical kinetic diagnostics and FTIR/XPS results were consistent with adsorption-coupled interfacial reduction, while DFT analysis provided qualitative support for the enhanced electronic responsiveness of H-BC. The OFG-enriched interface may facilitate short-range, non-electrostatic interfacial interactions and stabilize surface-associated Cr(III). Temperature-dependent apparent isotherm fitting suggested that elevated temperature favored the overall Cr(VI)-derived retention process under the tested conditions, and should not be interpreted as rigorous standard-state adsorption thermodynamics. Continuous-flow column leaching and accelerated wet–dry (W–D) aging experiments demonstrated that H-BC substantially suppressed the mobility of operationally filtered Cr(VI), achieving a maximum filtered-Cr(VI)-based retention efficiency of 99.98% under cyclic drying–rewetting conditions. Spatial configuration analysis indicated that homogeneous incorporation of H-BC improved soil–biochar contact and was more effective than stratified placement in limiting vertical filtered-Cr(VI) migration. Overall, oxidatively functionalized H-BC shows promise as a biomass-derived amendment for reducing Cr(VI) mobility in complex environmental matrices, although complete chromium mass redistribution will require future total-Cr and Cr(III)-resolved analyses. Full article

In this study, the effects of W, Cr, and Mo alloying elements on the microstructure and mechanical properties of the arc welding interface between TiC steel-bonded carbide and welding material were investigated using TEM, SEM, microhardness testing, and mechanical property testing. First-principles calculations were employed for verification. The results indicate that, under the experimental conditions, the shear strength of the arc welding interface between the ZDZC60 carbide and the multi-component composite welding material (enhanced with W, Cr, and Mo) was 83% higher than that before optimization. The order of the three metal atoms when substituting Ti atoms in TiC particles was determined as W > Mo > Cr. The “core–rim” structure of TiC particles in the partially melted zone (PMZ) of the arc welding interface was proposed. The coherent structure of TiC particles, characterized by (200)TiC//(200)TiMoC₂//(200)TiWC₂ and [011]TiC//[011]TiMoC2//[011]TiWC2, was identified. W and Mo atoms exert an inhibitory effect on the dissolution of TiC particles, while Cr atoms disperse in the binder phase in the form of carbides and solid solutions, thereby effectively strengthening the interface. Full article

This study presents the quantitative estimation of the effect of temperature on the mechanical properties of 5Cr-0.5Mo steels using an artificial neural network (ANN) model. The developed ANN model predicts yield strength (YS, MPa), ultimate tensile strength (UTS, MPa), elongation (El, %), and reduction in area (RA, %) at different service temperatures. Predictions were validated against experimental data at critical temperatures of 450 °C and 700 °C and found to show high accuracy. Predicted results show minimal errors of 3.84%, 2.3%, 2.2%, and 0.42% for YS, UTS, El, and RA, respectively at 450 °C, and 3.7%, 0.45%, 1.88%, and 0.19%, respectively at 700 °C. Furthermore, ten-fold cross-validation confirmed the generalization capability of the developed model, yielding high coefficients of determination and correlation coefficients together with low normalized prediction errors across all output variables. Despite the absence of explicit metallurgical descriptors, the ANN model successfully quantified the influence of temperature from 25 to 700 °C, demonstrating its effectiveness as a predictive tool for high-temperature Cr–Mo steels. Furthermore, a user-friendly graphical interface was developed to facilitate rapid property estimation, demonstrating the potential of the framework as a supportive tool for the preliminary assessment of high-temperature Cr–Mo steels. Full article