PubMed İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/397
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Article Parametric Study on the Behavior of CFRP-Strengthened Reinforced Concrete Deep Beams with Cut Circular Web Openings in Shear Spans(Nature Portfolio, 2026-02-17) Yagmur, ErenWeb openings in reinforced concrete deep beams are often necessary for functional purposes but substantially reduce structural performance. Carbon fiber-reinforced polymer (CFRP) strengthening is commonly employed to mitigate these effects. Previous studies typically examined openings in regions without stirrups or assumed closed stirrup configurations, overlooking the frequent stirrup damage that occurs in practice due to the high shear reinforcement in deep beams. In this study, three specimens from a prior experimental program were modeled in ABAQUS, and the numerical results were validated against experimental data. Openings of varying diameters were introduced by cutting reinforcements, and the beams were subsequently strengthened with CFRP laminates, and a parametric study was conducted. Results showed that increasing opening diameter markedly reduces load-carrying capacity and energy absoption, while thicker CFRP laminates partially restore performance. For example, a 300 mm opening in a 500 mm high unstrengthened beam reduced load capacity by 56% and energy absorption by 87%. Even when the opening diameter was less than one-third of the beam height, 1.8 mm CFRP laminates provided only limited improvement. Deep beam performance was strongly influenced by web opening size, and the effectiveness of CFRP strengthening was limited when stirrup integrity was compromised.Article Measuring Disaster Resilience in MENA Countries and Its Impact on Disaster Losses(Nature Portfolio, 2025-12-08) Demir, Abdullah; Dincer, Ali Ersin; Dincer, Nazire NergizDisaster resilience is a protective feature aimed at reducing the effects of natural disaster events and losses resulting from these events. This study develops a Disaster Resilience Index (DRI) for MENA countries to assess resilience across ten dimensions, including economic, social, institutional, infrastructural, and environmental factors. Unlike most prior studies, which focus on individual countries or use narrower sets of indicators, this study provides a multi-country, region-specific framework tailored to MENA's socio-economic and environmental heterogeneity. The index integrates geospatial data on disaster risk from geographic information systems (GIS) and a natural hazard risk dimension. Validation using disaster-related fatalities, supported by a dual PCA-based sensitivity analysis, confirms the robustness of the DRI and reveals that countries with stronger governance, higher human capital, and robust infrastructure tend to exhibit greater resilience, while fragile states and resource-dependent economies are more vulnerable. Notably, the DRI calculated using both dimension-specific and all-indicator PCA produces closely aligned values, indicating the choice of conducting PCA at the dimension level does not significantly alter the overall assessment of disaster resilience. These insights provide a foundation for targeted disaster risk reduction strategies and highlight areas where international cooperation and policy interventions can strengthen resilience in the region.Article Vim-Polyp: Multimodal Colon Polyp Dataset with Video, Histopathology, and Protein Expression(Nature Portfolio, 2025-12-03) Dogan, Refika Sultan; Akay, Ebru; Dogan, Serkan; Yilmaz, BulentThe dataset in this study includes 202 videos with a total of 422 minutes, reaching Kayseri City Hospital's gastroenterology department as colonoscopy videos and 1903 microscopy images between 2019 and 2021. It includes 399 colonoscopy, microscopy images, and pathological diagnoses of polyps, as well as immunohistochemical staining results for proteins that play an important role in the assessment of cancerous cells, such as staining results for p53 (clone: bp53-11), Ki-67 (clone: 30-9), CD34 (clone: QBend/10), PD-L1 (clone: SP142), BRAF (clone: V600E) and VEGF (clone: SP125). By sharing the data openly, we aim to facilitate benchmarking, exploratory analysis and transfer-learning studies on colorectal polyps and cancer. In combination with external datasets or pretrained models, the resource can help advance data-driven detection and characterisation work. The diverse range of polyps assigned to cancer stages from 201 patients makes this tool valuable for researchers and clinicians in furthering diagnosis and treatment.Article Citation - WoS: 7Citation - Scopus: 9Green Synthesis of Silver Nanoparticles From Pomegranate Peel and Their Application in PVA-Based Nanofibers for Coating Minced Meat(Nature Portfolio, 2025-05-16) Gencag, Burcu Sari; Kahraman, Kevser; Ekici, Lutfiye; Sari Gencag, BurcuIn this study, silver nanoparticles (AgNPs) were synthesized via a green method from pomegranate peel extract and incorporated into polyvinyl alcohol (PVA) to produce AgPVA nanofibers through electrospinning. Nanofibers containing different silver concentrations (0.5, 1, and 1.5% Ag) were used as coating materials to coat minced meat, and their effects on various quality parameters during storage at 4 degrees C were evaluated. FTIR, XRD, SEM, and antibacterial analyses were conducted for the characterization of AgNPs and AgPVA nanofibers. To assess the quality characteristics of the minced meat during storage, pH, color, peroxide, TBARS, and microbiological analyses were performed. The results indicated that silver concentrations up to 1% could delay oxidation in minced meat and help preserve its quality. Compared with the other samples, the samples coated with 0.5% AgPVA (A1) and 1.0% AgPVA (A2) nanofibers exhibited a significant antimicrobial effect at the 6-day storage point (p < 0.05). The migration of AgNPs into minced meat was monitored during storage, and all migration values remained below the European food safety authority (EFSA) safety limit of 0.05 mg/kg, demonstrating the safety of the coatings. These findings suggest that AgPVA nanofibers synthesized via a green method could be a promising approach for extending the shelf life of perishable foods by reducing spoilage.