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Reconstruction of Historical Buildings Using Social Media Data: A Case Study from the World Cultural Heritage List
No full textCultural and natural heritage assets, as a set of tangible and intangible values that reveal the shared past and historical accumulations of the communities living together, are important not only for the past but also for the transfer to future generations and are the responsibility of all nations of the world. Today's digitalized information age, development, and change in science and technology contribute to producing highly accurate three-dimensional (3D) inventories of these cultural heritages. However, in addition to natural degradation and destruction processes, unexpected events such as war, terrorist attacks, and natural disasters can hinder the formulation of the traditional inventories. At this point, it is important to carry out 3D modeling studies using crowdsourced images and videos from social media, to enhance modeling accuracy and support digital documentation, virtual museum initiatives, and heritage preservation. This study aims to present a strategy following the Structure-fromMotion approach to create 3D models of cultural heritage assets by using shared crowdsourced images and videos collected via social media platforms and applying a normalization procedure for scale standardization to assess model accuracy. Data obtained during nighttime, snowy conditions, or overly filtered captures were excluded, and a segmentation procedure using the Segment Anything model was implemented to remove irrelevant objects. As a result, an approach that can be used in inventory studies has been presented by using images and videos shared by users on social media platforms through an integrated and mutually supportive methodology. Quantitative analysis using the M3C2 method showed that RMSE values ranged from 0.0010 to 0.0036 across the models, with over 93% of the matched points falling within ±1σ. These results confirm the reliability of the proposed approach for large-scale digital heritage documentation.</p
Response of Seismically Isolated Bridges due to Property Modification in Friction Pendulum Bearings Arising from Environmental and Construction Irregularities
No full textA comparative study on crystal violet and congo red dyes removal from wastewater using Trichoderma reesei biomass: Equilibrium, kinetic, thermodynamic studies, and error analysis
No full textThis study examined the adsorption of crystal violet (CV) and Congo red (CR) dyes utilizing Trichoderma reesei biomass. The physicochemical characteristics were examined by FTIR-ATR, SEM, zeta potential, and pHpzc tests. The influences of pH, initial dye concentration, temperature, adsorbent dosage, and contact time on biosorption capacity were examined and optimized by a batch experimental approach, subsequently followed by modeling the kinetics, equilibrium, and thermodynamics of the adsorption process. The adsorption isotherm was utilized in multiple two- and three-parameter non-linear isotherm models. The Langmuir model indicated adsorption capacities for CV and CR dyes of 40.35 ± 2.34 mg/g and 30.44 ± 1.75 mg/g at 298 K, respectively. Adsorption kinetics indicated that the adsorption adhered to a pseudo-second order kinetic, and the intraparticle diffusion suggested that the process transpired in two stages. Moreover, thermodynamic modeling indicated that adsorption was spontaneous, characterized as an exothermic (∆Ho=−24.91 kJ/mol) process for CV dye and an endothermic (∆Ho=32.02 kJ/mol) process for CR dye. Real wastewater research was undertaken, indicating that T. reesei biomass was successful in diverse aquatic settings. Reusability studies demonstrated that the biomass exhibited significant efficacy until the sixth cycle. Based on the results, T. reesei biomass demonstrated significant efficacy in the adsorption of both anionic and cationic dyes
Facial Stress and Fatigue Recognition via Emotion Weighting: A Deep Learning Approach
No full textThis research addresses the gap in direct facial expression-based detection of complex emotional states like stress and fatigue. We propose a novel methodology employing a weighted summation of basic emotion probabilities, outputted by deep learning models, to calculate continuous stress and fatigue scores. Crucially, these emotion weights are empirically justified and grounded in established psychological and neuroscientific literature. Evaluating CNN, hybrid (DDAMFN), and Transformer-based (ViT, BEiT) architectures, our results demonstrate the superior performance of Transformer models, particularly ViT, in aligning with human-annotated ground truth data for stress and fatigue. ViT achieved “almost perfect” Cohen’s Kappa (κ = 0.81) for stress and “substantial” (κ = 0.72) for fatigue, validating the human-relevance of our emotion-based formulation. This study highlights the effectiveness of Transformer architectures and literature-informed emotion weights for direct and accurate stress and fatigue detection from facial expressions, paving the way for real-world applications in monitoring and well-being
NiO-SnO2 nanocomposite as an adsorbent for the preconcentration of manganese ions in chamomile tea extract
No full textMatricaria chamomilla L. , referred to as chamomile, is a well-known medicinal plant that is widely distributed throughout the world. In this study, a novel NiO-SnO2 nanocomposite- assisted preconcentration method was established for efficient extraction and separation of manganese ions from chamomile tea extract. This preconcentration method was coupled with flame atomic absorption spectroscopy (FAAS). NiO-SnO2 nanocomposites were synthesized using simple one-pot co-precipitation procedure and calcined at 650 °C to obtain nanoparticles with sizes below 100 nm. X-ray diffraction (XRD) analysis indicated that the crystallite size of NiO-SnO2 nanocomposites was estimated to be 46.03 nm using the Monshi–Scherrer equation. The LOD (limit of detection) and linear working range were determined as 3.6 μg/L and 10–100 μg/L, respectively. The proposed method was successfully validated, and recoveries ranged from 87.2 %–117.0 %. NiO-SnO2 nanocomposites represent a promising low-cost adsorbent for the preconcentration and subsequent determination of other heavy metal ions in diverse herbal extracts
Experimental investigation and assessment of a newly designed hybrid hydrogen reactor for sustainable fuel production
No full textWith the increasing need for clean and sustainable energy sources, hydrogen has become a crucial energy carrier owing to its high energy density and zero-emission properties. This study presents a novel hybrid photoelectrochemical (PEC)-conventional electrolysis system that integrates the advantageous features of both PEC and conventional electrolysis technologies, providing distinct benefits. A significant advantage is further the ability to constantly produce hydrogen, even without solar irradiation. An experimental examination and thermodynamic performance evaluation of a hybrid hydrogen reactor to produce clean hydrogen is presented. The Design Expert software and Response Surface Methodology (RSM) were used to assess the experimental data and simulate the operational conditions and factors, such as mass flow rate, operating temperature and sun irradiation. At a 49 cm2 active electrode area, the system produced 1.226 µg/s of hydrogen with energy and exergy efficiencies of 3.78% and 3.86%, respectively. The results underscore the significance of coating material selection and process optimization in enhancing efficient and sustainable hydrogen generation methods
Powder metallurgy for dental biomaterials: Applications, processing, properties and clinical relevance
No full textAdvances in powder metallurgy (PM) have revolutionized the fabrication of dental biomaterials by enabling precise microstructural control and tailored porosity (up to 80 % porosity in scaffolds) while simultaneously reducing waste and processing time. Although conventional PM processes offer a versatile toolkit for dental applications, consolidation techniques achieve near-full densification (exceeding 85 % of theoretical density) and refine microstructures in metallic and ceramic dental restoratives, resulting in enhanced mechanical integrity (compressive strength up to 203 MPa for TiB2/Ti composites) and biocompatibility. Post-processing treatments, ranging from thermal unbinding and sintering schedules to surface modifications, further optimize the mechanical performance (Young's modulus matching bone at 2.2–12.1 GPa), surface finish, and corrosion resistance of the PM-derived dental components. A diverse array of biomaterials, including titanium–indium alloys for endodontic posts and cobalt–chromium partial denture frameworks, has been successfully produced via PM, demonstrating favorable osseointegration and mechanical performance (tensile strength up to 290 MPa for Ta-Zr alloys). Comprehensive performance evaluations, including fatigue testing, wear analysis, and cytocompatibility assays, confirm the clinical viability of PM-fabricated dental biomaterials. Comparative analyses further elucidate the trade-offs between process parameters, part complexity, and cost efficiency, thereby guiding rational selection for specific prosthetic applications. Nonetheless, challenges persist in scaling PM processes for custom dental geometries, managing the residual porosity (5–15 % in sintered parts), and ensuring consistent biocompatibility across diverse alloy systems. This review aims to cover and analyze these issues by mentioning recent advancements, current limitations, and the future landscape of dental PM-derived biomaterial fabrication in a wide framework
Effect of Enhanced Recovery After Surgery programs on surgical site infection and 30-day readmission in patients undergoing gastro-intestinal procedures: An umbrella review
No full textBackground: Enhanced Recovery After Surgery programs have been implemented across surgical specialties; however, their effectiveness in reducing surgical site infection and 30-day hospital readmission remains unclear. Objective: To determine the effect of Enhanced Recovery After Surgery programs on the clinical outcomes of surgical site infection and readmission and identify items of and implementation strategies for such programs. Design: An umbrella review of published systematic reviews. Methods: Systematic searches of MEDLINE, Embase, CINAHL, Cochrane Library, and Scopus databases were conducted in January 2025. Systematic reviews of randomised controlled trials and non-randomised studies of interventions comparing Enhanced Recovery After Surgery programs with standard care in adults after major open or laparoscopic gastrointestinal surgery, focusing on surgical site infection and 30-day hospital readmission, were included. Review quality and certainty of evidence were assessed using A MeaSurement Tool to Assess systematic Reviews (AMSTAR 2) and GRADE (Grading of Recommendations Assessment, Development and Evaluation) tools. Results: 49 reviews were included in the analysis. Meta-analysis of 42 unique primary randomised controlled trials with 5112 patients suggests a significant association between Enhanced Recovery After Surgery programs use and surgical site infection reduction (estimated odds ratio 0.70, 95 % confidence interval 0.59–0.82, p < 0.001, I2 = 0 %). Meta-analysis of 53 primary randomised controlled trials with 7360 patients suggests no significant relationship between Enhanced Recovery After Surgery programs and hospital readmission (estimated odds ratio 1.025, 95 % confidence interval 0.85–1.23, p = 0.792, I2 = 0 %). Summary estimates for surgical site infection were similar across non-randomised studies of interventions. GRADE assessments suggest ‘very low’ certainty across outcomes. Enhanced Recovery After Surgery programs included 5 to 28 components; implementation strategies were not described. Discussion: Results suggest an association between Enhanced Recovery After Surgery programs and reductions in surgical site infection, and no relationship between hospital readmissions. However, the body of evidence is weak and inconclusive. These results also indicate heterogeneity in compliance with Enhanced Recovery After Surgery, reflecting the complexity in standardising this surgical care pathway. Conclusions: Well-controlled primary research is warranted to understand the impact of Enhanced Recovery After Surgery programs. Registration: PROSPERO registration number: CRD42024503357. Social media abstract: Enhanced Recovery After Surgery programs may significantly reduce surgical site infections after GI surgery but there is no clear impact on 30-day readmissions
