Search Results (71,140)

Background/Objectives: In this work, a series of six new indazole-benzimidazole hybrids (M1–M6) were designed, synthesized, and fully characterized. The design of these compounds was based on the combination of two pharmacophoric units, indazole and benzimidazole, both known for their broad spectrum of biological activities. Methods: The molecular hybridization strategy was planned to combine these scaffolds through an effective synthetic pathway, using 6-nitroindazole, two 2-mercaptobenzimidazoles, and 1,3- or 1,5-dihaloalkanes as key precursors, affording the desired hybrids in good yields and with enhanced biological activity. Quantum chemical calculations were performed to investigate the structural, electronic, and electrostatic properties of M1–M6 molecules using Density Functional Theory (DFT) at the B3LYP/6-311++G(d,p) level. The antimicrobial activity efficacy of these compounds was assessed in vitro against four Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, and Lactobacillus plantarum), four Gram-negative bacteria (Salmonella enteritidis, Escherichia coli, Campylobacter coli, Campylobacter jejuni), and four fungal strains (Saccharomyces cerevisiae, Candida albicans, Candida tropicalis, and Candida glabrata) using ampicillin and tetracycline as reference standard drugs. Results: Among the series, compound M6 exhibited remarkable antimicrobial activity, with minimum inhibitory concentrations (MIC) of 1.95 µg/mL against S. cerevisiae and C. tropicalis, and 3.90 µg/mL against S. aureus, B. cereus, and S. enteritidis, while the standards Ampicillin (AmB) (MIC ≥ 15.62 µg/mL) and Tetracycline (TET) (MIC ≥ 7.81 µg/mL) exhibited higher MIC values. To gain molecular insights into the compounds, an in silico docking study was performed to determine the interactions of M1–M6 ligands against the antimicrobial target beta-ketoacyl-acyl carrier protein (ACP) synthase III complexed with malonyl-COA (PDB ID: 1HNJ). Molecular modeling data provided valuable information on the structure-activity relationship (SAR) and the binding modes influencing the candidate ligand-protein recognition. Amino acid residues, such as Arg249, located in the solvent-exposed region, were essential for hydrogen bonding with the nitro group of the 6-nitroindazole moiety. Furthermore, polar side chains such as Asn274, Asn247, and His244 participated in interactions mediated by hydrogen bonding with the 5-nitrobenzimidazole moiety of these compound series. Conclusions: The hybridization of indazole and benzimidazole scaffolds produced compounds with promising antimicrobial activity, particularly M6, which demonstrated superior potency compared to standard antibiotics. Computational and docking analyses provided insights into the structure–activity relationships, highlighting these hybrids as potential candidates for antimicrobial drug development. Full article

The widespread adoption of virtual classrooms during the COVID-19 pandemic accelerated the integration of Learning Management Systems (LMSs) into Higher Education, positioning them as essential tools in blended learning environments. LMSs provide teachers with a wide range of tools and functionalities, generating heterogeneous teaching strategies and providing many useful indicators for analysis. However, the complexity of log data combined with the intricacies of hybrid environments presents a significant challenge. This paper presents a quantitative approach to analysing LMS log data in Higher Education, with a specific focus on identifying and characterising teaching strategies implemented in the post-pandemic context. It seeks to examine the extent to which virtual classrooms have been effectively integrated into teaching practices and to assess how different techno-pedagogical approaches influence students’ academic performance. Moreover, we try to develop and define a comprehensive methodology for data treatment, including selection of analytical variables, the identification and clustering of usage profiles based on LMS interactions, and a comparative interpretative analysis of the findings. Our results suggest that the techno-pedagogical strategies are not uniformly effective across all areas of knowledge. This highlights the need for a more nuanced understanding of how these strategies interact with disciplinary traditions, pedagogical practices, and student profiles. Full article

The extensive use of clothianidin pesticide poses significant risks to non-target organisms and water resources. In this study, NiO-GO is reported as an effective photocatalyst for the degradation of clothianidin in aqueous medium. Nickel oxide (NiO) nanoparticles were synthesized by a green method using Pisum sativum (pea) peel extract, which serves as a natural reducing and stabilizing agent, and subsequently integrated with graphene oxide (GO) through ultrasonication to form a NiO-GO composite in a 1:1 ratio. The materials were characterized by various techniques. Photocatalytic degradation of clothianidin under natural sunlight was systematically investigated, assessing the effects of pH, catalyst dosage, initial pollutant concentration, and agitation speed. The NiO-GO composite exhibited superior photocatalytic performance (96% degradation at pH 3 within 60 min) compared to pristine NiO and GO, with a rate constant 4.4 and 3.3 times higher, respectively. The as-prepared NiO-GO photocatalyst exhibited nearly consistent degradation efficiency over two successive cycles, demonstrating its excellent structural stability and reusability. The enhanced performance is attributed to improved charge separation afforded by GO support. This low-cost, green, and efficient NiO-GO photocatalyst demonstrates promising potential for sustainable pesticide remediation in aqueous environments. Full article

This study investigates the performance, emissions, and physicochemical characteristics of a small-scale gas turbine fueled with Jet A and camelina biodiesel blends (B10, B20, and B30). The blends were characterized by slightly higher density (up to +3%), viscosity (+12–18%), and lower heating value (−7–9%) compared to Jet A. These fuel properties influenced the combustion behavior and overall turbine response. Experimental results showed that exhaust gas temperature decreased by 40–60 °C and specific fuel consumption (SFC) increased by 5–8% at idle, while thrust variation remained below 2% across all operating regimes. Fuel flow was reduced by 4–9% depending on the blend ratio, confirming efficient atomization despite the higher viscosity. Emission measurements indicated a 20–30% reduction in SO₂ and a 10–35% increase in CO at low load, mainly due to the sulfur-free composition and lower combustion temperature of biodiesel. Transient response analysis revealed that biodiesel blends mitigated overshoot and undershoot amplitudes during load changes, improving combustion stability. Overall, the results demonstrate that camelina biodiesel–Jet A blends up to 30% ensure stable turbine operation with quantifiable environmental benefits and minimal performance penalties, confirming their suitability as sustainable aviation fuels (SAFs). Full article

Molybdenum oxide (MoO_X) has been widely utilized as a hole transport layer (HTL) in crystalline silicon (c-Si) solar cells, owing to characteristics such as a wide bandgap and high work function. However, the relatively low conductivity of MoO_X films and their poor contact performance at the MoO_X-based hole-selective contact severely degrade device performance, particularly because they limit the fill factor (FF). Oxygen vacancies are of paramount importance in governing the conductivity of MoO_X films. In this work, MoO_X films were modified through ultraviolet irradiation (UV-MoO_X), resulting in MoO_X films with tunable oxygen vacancies. Compared to untreated MoO_X films, UV-MoO_X films contain a higher density of oxygen vacancies, leading to an enhancement in conductivity (2.124 × 10⁻³ S/m). In addition, the UV-MoO_X rear contact exhibits excellent contact performance, with a contact resistance of 20.61 mΩ·cm², which is significantly lower than that of the untreated device. Consequently, the application of UV-MoO_X enables outstanding hole selectivity. The power conversion efficiency (PCE) of the solar cell with an n-Si/i-a-Si:H/UV-MoO_X/Ag rear contact reaches 24.15%, with an excellent FF of 84.82%. Full article

Copper (Cu) doping is recognized as an effective strategy to enhance the electrochemical properties of LiNi_1−x−yCo_xMn_yO₂ (NCM) cathode materials. However, the influence of Cu²⁺ doping on particle size and grain boundary fusion remains insufficiently explored. A simple microwave-assisted solution combustion synthesis method was used to introduce Cu²⁺ into LiNi_0.5Co_0.2Mn_0.3O₂ (NCM523), aiming to regulate particle size and grain boundary fusion. The results demonstrate that increasing the Cu²⁺ doping content promotes particle growth, while an appropriate doping level reduces the degree of grain boundary fusion and cation mixing. Benefiting from these structural improvements, the optimized LiNi_0.5Co_0.2Mn_0.29Cu_0.01O₂ (Cu‒1) cathode exhibits significantly enhanced electrochemical performance, delivering a discharge capacity of 128.6 mAh g⁻¹ after 100 cycles at 0.2 C, which is 32 mAh g⁻¹ higher than value of the undoped sample (96.6 mAh g⁻¹). These findings underscore that tailored Cu²⁺ doping can effectively optimize the microstructure of NCM523, leading to superior cycling stability, and provide new insights into the design of high-performance NCM cathodes. Full article

Background and Objectives: Acute acalculous cholecystitis (AAC) is rare, mostly in older males, with cardiovascular diseases, diabetes, critical illness, or systemic infection. Antibiotherapy before or after cholecystectomy is important for preventing septic shock and postoperative infections. Increasing antibiotic resistance was recently noted and can complicate antibiotherapy. Materials and Methods: A retrospective study of all patients who underwent cholecystectomy between 2018 and 2024 in the Clinical Emergency Hospital of Craiova was performed. The etiology of AAC, complications, hospitalization duration, mortality, positive bile cultures, and in vitro antibiotic resistance were analyzed. Results: A total of 802 calculous and 54 AAC were recorded. Patients with AAC were predominantly males (OR = 1.767, p = 0.043) with diabetes (OR = 2.049, p = 0.014) and were older (66.6 ± 13.2 versus 61.4 ± 15.6, p = 0.014). Mortality was significantly higher in AAC (18.5 versus 3.6%, OR= 6.058, p < 0.001), with longer hospitalization (mean 9.7 versus 8.4 days) and more perforation. Positive bile cultures were recorded in 60.5–66.2% of cases, with a similar etiology in both forms of acute cholecystitis (mostly Gram-negative species, Enterococcus, and Staphylococcus); 10 ESBL Escherichia coli and Klebsiella strains, 11 Staphylococcus aureus MRSA, and 1 Enterococcus VRE strain were recorded. Antibiotic susceptibility in vitro was similar in both AAC and calculous cholecystitis. Significant resistance to cephalosporins and quinolones was recorded; the lowest resistance was noted for amikacin, carbapenems, chloramphenicol, colistin (Gram-negative bacteria), and vancomycin. Conclusions: AAC was encountered in older males with diabetes, with a higher rate of complications and in-hospital mortality. Bile cultures were positive in 60.5–66.2%, predominantly with Gram-negative, Enterococcus, and Staphylococcus species. Significant in vitro resistance to cephalosporins and quinolones was found. Full article

To address the issue of material spillage and equipment wear caused by conveyor belt deviation in complex industrial scenarios, this study proposes a detection method based on an improved U-Net. The approach adopts U-Net as the backbone network, with a ResNet34 encoder to enhance feature extraction capability. At the skip connections, a Multi-scale Adaptive Guidance Attention (MASAG) module is embedded to strengthen the fusion of semantic and detailed features. In the loss function design, a boundary loss is incorporated to improve edge segmentation accuracy. Furthermore, the segmentation results are refined via edge detection and RANSAC regression, and a reference line is constructed based on the physical stability of rollers in the image to enable quantitative measurement of deviation. Experiments on a self-constructed dataset demonstrate that the proposed method achieves higher accuracy (99.77%) compared with the baseline U-Net (99.65%) and also surpasses other categories of approaches, including detection-based (YOLOv5s), anchor-point-based (UFLD), and segmentation-based approaches represented by SEU-Net and DeepLabV3+, thereby exhibiting strong robustness and real-time performance across diverse complex operating conditions. The results validate the effectiveness of this method in practical applications and provide a reliable technical pathway for the development of intelligent monitoring systems for mining conveyor belts. Full article

Early detection of pancreatic ductal adenocarcinoma (PDAC) could extend patient survival, and biomarkers to facilitate this are urgently needed. Here, we performed a second independent validation of PancreaSure, a 5-plex serum biomarker signature to detect early-stage PDAC in high-risk individuals. In contrast to the first validation, this study’s cohort was preemptively balanced for age and sex and only included samples stored for fewer than 5 years. The primary endpoint was to measure test sensitivity against the performance target of 65%. Measuring specificity against the performance target of 90% and comparing test performance to that of carbohydrate antigen 19-9 (CA 19-9) alone were secondary endpoints. Signature analytes were retrospectively measured in serum from a blinded independent cohort of Stage I and II PDAC cases and high-risk controls. A predictive signal for PDAC was generated from a predefined cutoff established in a previous model development study. PancreaSure distinguished early-stage PDAC from controls with 76.5% sensitivity (95% CI, 67.7–83.9), significantly higher than the performance target (p = 0.005). PancreaSure achieved 87.8% specificity (95% CI, 83.9–91.4), similar to the performance goal, and significantly outperformed sensitivity of CA 19-9 alone (p = 0.02). These results confirm that PancreaSure performs well at detecting early-stage PDAC in high-risk individuals. Full article

Infrared images have garnered significant interest due to their superior performance, driving extensive research on visible-to-infrared image translation. However, existing cross-domain generation methods lack specialization for infrared image generation under aerial perspective, leading to distribution inconsistencies between synthetic and real infrared images and failing to mitigate challenges like small-target blurring and background interference under aerial views. To address these issues, we propose an RGB-to-infrared image generation method based on the Brownian bridge diffusion model for aerial perspective. Technically, we optimize the diffusion coefficient and variance scheduling of the Brownian bridge by introducing a parabolic function, design a Laplacian of Gaussian (LOG) loss that fuses high-, medium-, and low-frequency features, and construct two core modules: a modality enhancement module that integrates spectral involution and cross-modal fusion, and an information guidance module based on wavelet decomposition. Experimental results demonstrate state-of-the-art performance: the method achieves a PSNR of 15.06 and an SSIM of 49.47, which are 1.5% and 1.2% higher than the suboptimal baseline BBDM-VQ4, respectively; its FID is reduced to 36.83, representing a 25.6% decrease compared to BBDM-VQ4, and its LPIPS is 2.0% lower than that of BBDM-VQ4. This approach effectively eliminates distribution biases induced by small-target blurring and background interference under aerial perspective while ensuring the semantic consistency of generated infrared images. Full article

Long-term effects of concussions, particularly in contact sport athletes, have been linked to changes in neuronal health. Lipid dysregulation has emerged as a potential contributor to neuronal injury and may serve as a measurable biomarker of brain pathology. This study investigated cognitive scores and serum lipid biomarkers in retired rugby players with a history of concussion to assess their association with concussion exposure. Serum levels of 24-hydroxycholesterol (24-HC), 25-HC, 27-HC, total triglycerides, and ceramide were compared between retired rugby players with a history of repeated concussions (n = 26) and non-contact sport controls (n = 19). ELISA-based quantification and statistical analyses identified significant group differences. Concussed athletes exhibited significantly lower serum 24-HC and significantly higher levels of 27-HC, triglycerides, and ceramide compared to controls, while no significant difference was observed for 25-HC. These findings indicate that repeated concussion is associated with reductions in cognitive performance and persistent alterations in serum lipid profiles. The observed lipid changes, particularly in 24-HC, 27-HC, ceramide, and triglycerides, may serve as measurable biomarkers of concussion-related biochemical alterations, providing a foundation for future studies aimed at monitoring neurological health in at-risk populations. Full article

Human herpesvirus 6 (HHV-6) is a common virus that can reactivate in immunocompromised patients, including lung transplant (LT) recipients. This study aimed to evaluate the clinical and functional implications of HHV-6 infection in LT patients through a retrospective analysis of 175 individuals who underwent lung transplantation at the City of Health and Sciences of Turin between 2014 and 2023. Surveillance bronchoscopies—including bronchoalveolar lavage (BAL) and transbronchial biopsies—were performed at scheduled intervals over a two-year period to detect HHV-6 and other pathogens, and to assess acute rejection. Spirometries were performed to evaluate graft function. Among the cohort, 33% of 822 BAL samples tested were positive for HHV-6, with a notable association between high viral load (≥500 copies/mL) and the development of post-transplant lymphoproliferative disorder (PTLD) (13% vs. 1%, p = 0.02) at 1 month and (9% vs. 1%, p = 0.026) at 12 months. Co-infection with CMV (78% in positives vs. 55% in negatives; p = 0.006), Epstein–Barr virus (EBV) (35% vs. 16%; p = 0.010), and bacterial and fungal infection (specifically, a higher rate of isolation of Achromobacter xylosoxidans (13%), p = 0.010) was frequently observed in conjunction with HHV-6 positivity. Notably, patients with at least one HHV-6 positive BAL exhibited a significant reduction in forced vital capacity (FVC) at multiple follow-up points, FVC 82% in positives vs. 92% in negatives (p = 0.038) at 4 months and 87% vs. 98% p = 0.033 at 8 months and 87% vs. 99% p = 0.038 at 24 months. No direct associations with acute rejection or overall survival were found. By means of this study, we provide a wide overview of HHV-6 in lung transplant recipients, filling in a gap of evidence in the field. We report a remarkable incidence and a significant association with acknowledged clinically relevant viral infections, PTLD, and functional tests decline, with no association with mortality. Full article

Background/Objectives: Vitamin D deficiency contributes to pathological vertebral fragility (path-VF), including fragility fractures and early pedicle screw loosening after posterior instrumented spinal fusion (PISF). Supplementation practices remain inconsistent. This retrospective study evaluated whether patients with path-VF receive appropriate vitamin D3 (Vit.D3) supplementation and assessed the dose–response relationship between daily intake and path-VF risk, particularly in older adults. Methods: A total of 210 patients treated with kyphoplasty or PISF (2022–2023) were classified into a path-VF or control group. Daily oral Vit.D3 intake was categorised as Zero- (0 IU), Low- (<2000 IU), or High-Dose (≥2000 IU). Statistical analyses were performed for each dosage group, including subgroup analyses for patients aged ≥67.5 years. Vertebral BMD was estimated using mean Hounsfield Units (HU) from T11–L5. Results: Patients in the path-VF group received significantly lower Vit.D3 doses than controls (1431.4 ± 1055.7 vs. 2366.7 ± 1186.7 IU/day, p < 0.001). Low-dose supplementation was associated with a markedly increased risk of path-VF compared with high-dose in the overall cohort (OR = 6.5, p = 0.003) and in patients aged ≥67.5 years (OR = 8.6, p = 0.008). Logistic regression identified a threshold of 1900 IU/day (AUC = 0.805). Mean vertebral HU values were significantly lower in the path-VF group than in controls (71.9 ± 29.1 vs. 133.5 ± 52.6, p < 0.001), and no consistent HU gains were observed with increasing Vit.D3 dosage. Conclusions: Low-dose Vit.D3 supplementation was associated with increased path-VF risk, especially in patients aged >67.5 years. Patients without path-VF had received significantly higher doses, suggesting broader benefits of adequate Vit.D3 beyond bone density. A daily intake above 1900 IU may serve as a practical threshold for at-risk elderly patients. Full article

Background/Objectives: Percutaneous dilatational tracheostomy (PDT) is a commonly performed procedure in critically ill patients. Various guidance techniques, including anatomical landmark-guided (ALG), ultrasound-guided (USG) and bronchoscopy-guided (BG), aim to enhance procedural safety and efficacy. This systematic review and meta-analysis aimed to compare the safety and efficacy across ALG, USG, and BG techniques in PDT, focusing on complications and procedure times. Methods: A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted. Studies identified through PubMed, CENTRAL, Scopus, and Web of Science databases up to July 2025 comparing ALG, USG, and BG PDT were included. Primary outcomes were minor and major bleeding, with transient hypoxia, transient hypotension, endotracheal tube cuff puncture, pneumothorax, and procedure time as secondary outcomes. Data were pooled using random-effects models, with risk ratios (RR) and 95% confidence intervals (CI) for complications and mean differences for procedure times. Heterogeneity was assessed using I² statistics, with Bonferroni correction for multiple comparisons. Results: This meta-analysis included five RCTs (568 patients) comparing USG vs. ALG, six RCTs (404 patients) comparing USG vs. BG, and five RCTs (448 patients) comparing ALG vs. BG. USG significantly reduced minor bleeding compared to ALG (RR 2.30, 95% CI 1.38–3.84, p = 0.001) and BG (RR 0.42, 95% CI 0.20–0.91, p = 0.02), and major bleeding compared to ALG (RR 2.62, 95% CI 1.00–6.86, p = 0.04). ALG was associated with higher minor bleeding risk than BG (RR 1.81, 95% CI 1.05–3.12, p = 0.03). No significant differences were found for transient hypoxia, hypotension, endotracheal tube cuff puncture, or pneumothorax across comparisons, though trends suggested lower hypoxia risk with USG and higher pneumothorax risk with ALG. Procedure times were similar (ALG: 10.4 min, USG: 11.7 min, BG: 12.7 min; p = 0.493). Some rare complications, like paratracheal placement and mediastinitis, were too infrequent for analysis. Conclusions: USG PDT significantly reduces the risk of minor and major bleeding relative to ALG and minor bleeding compared to BG, without prolonging procedure time. USG and BG show comparable safety for most non-bleeding outcomes. No significant differences in procedure times. Future research should focus on larger RCTs to assess rare complications and explore hybrid USG-BG approaches to optimize PDT safety and efficacy. Full article

Additive manufacturing technologies are no longer limited to rapid prototyping but are increasingly used for low-volume production of functional end-use components. Among advanced AM techniques, HP Multi-Jet Fusion (MJF) stands out for its high precision and efficiency. Polyamides, thanks to their balanced mechanical and thermal properties, are commonly used as building materials in this technology. However, these materials are notoriously difficult to bond with conventional adhesives. This study investigates the shear strength of bonded joints made from two frequently used MJF materials—PA12 and glass-bead-filled PA12—using four different industrial adhesives. Experimental procedures were conducted according to ASTM standards. Specimens for single-lap-shear tests were fabricated on an HP MJF 4200 series printer, bonded using a custom jig, and tested on a Zwick-Roell Z250 electro-mechanical testing machine. Surface roughness of the adherends was measured with a 3D optical microscope to assess its influence on bonding performance. The polyurethane-based adhesive (3M Scotch-Weld DP620NS) demonstrated superior performance with maximum shear strengths of 5.0 ± 0.35 MPa for PA12 and 4.4 ± 0.03 MPa for PA12GB, representing 30% and 17% higher strength, respectively, compared to epoxy-based alternatives. The hybrid cyanoacrylate–epoxy adhesive (Loctite HY4090) was the only system showing improved performance with glass-bead-reinforced substrate (16.5% increase from PA12 to PA12GB). Statistical analysis confirmed significant differences between adhesive types (F_3,24 = 31.37, p < 0.001), with adhesive selection accounting for 65.7% of total performance variance. In addition to the experimental work, a finite element-based numerical simulation was performed to analyze the distribution of shear and peel stresses across the adhesive layer using Siemens Simcenter 3D 2406 software with the NX Nastran solver. The numerical results were compared with analytical predictions from the Volkersen and Goland–Reissner models. Full article