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Measuring Disaster Resilience in MENA Countries and Its Impact on Disaster Losses
No full textDisaster 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. © The Author(s) 2025
Enhancing Oil Rejection in PVDL and PSF Membranes: The Role of SiO2 NPS
No full textOily water negatively affects both land and marine ecosystems. To combat this, membrane production can effectively treat oil waste and recycle over 90% of it. This study compares the influence of SiO2 nanoparticles on oil rejection in two types of membranes: polyvinylidene fluoride (PVDF) and polysulfone (PSF). The SiO2 NPs are characterized by FTIR, SEM analysis, and zeta potential measurements. SiO2 NPs embedded PSF and PVDF membranes were characterized by FTIR, SEM analysis, contact angle, water permeability, oil rejection measurements, and recycling experiments. The results of the experiments showed that oil rejection reached maximum values of 92.2% for 2 wt% PSF/SiO2, and 94.1% for 2 wt% PVDF/SiO2 membranes. The experimental results demonstrate that the incorporation of SiO2 nanoparticles enhances the oil rejection efficiency of two distinct membrane types, exhibiting notable performance disparities contingent on the selected membrane material. This methodology achieves a recycling rate of over 90% for oil waste, signifying a substantial advancement in environmental protection and sustainable development. Consequently, the membrane production technique is regarded as an efficacious approach for the management and recycling of oil waste
Combining N-Grams and Graph Convolution for Text Classification
No full textBakal, Mehmet/0000-0003-2897-3894Text classification, a cornerstone of natural language processing (NLP), finds applications in diverse areas, from sentiment analysis to topic categorization. While deep learning models have recently dominated the field, traditional n-gram-driven approaches often struggle to achieve comparable performance, particularly on large datasets. This gap largely stems from deep learning' s superior ability to capture contextual information through word embeddings. This paper explores a novel approach to leverage the often-overlooked power of n-gram features for enriching word representations and boosting text classification accuracy. We propose a method that transforms textual data into graph structures, utilizing discriminative n-gram series to establish long-range relationships between words. By training a graph convolution network on these graphs, we derive contextually enhanced word embeddings that encapsulate dependencies extending beyond local contexts. Our experiments demonstrate that integrating these enriched embeddings into an long-short term memory (LSTM) model for text classification leads to around 2% improvements in classification performance across diverse datasets. This achievement highlights the synergy of combining traditional n-gram features with graph-based deep learning techniques for building more powerful text classifiers.Scientific and Technological Research Council of Turkiye (TUBITAK) [122E103]This research is funded by the Scientific and Technological Research Council of Turkiye (TUBITAK) through 3501 Career Development Program with grant number 122E103. The authors also express their gratitude to Google Cloud Services for providing academic credit support that facilitated portions of this work
Atomic Structure and Properties of Amorphous Boron Carbon Nitride (BC2N): An Ab Initio Study
No full textThis study investigates the atomic structure and properties of amorphous boron carbon nitride (a- BC2N) using ab initio molecular dynamics simulations. Structural analysis reveals a layer-like topology with varied bonding environments. Unlike the ordered alternating C-C and B-N layers found in the lowest-energy crystalline BC2N structure, a-BC2N features a solid-solution-like arrangement, with B, C, and N atoms randomly distributed within each layer. This randomness gives rise to small, distinct C-rich and BN-rich domains and irregular short zigzag chains of C-C and B-N bonds within each layer. Electronic structure analysis suggests that a-BC2N is likely a semiconductor. Mechanically, a-BC2N displays properties typical of layered materials but with an enhanced bulk modulus
Benefiting From Both Ethanol Oxidation and Bidentate Thiol Groups of DHLA Ligands Under Photoirradiation for Synthesis of Au Nanoparticles With Their Catalytic and Peroxidase Like Activity
No full textIn this work, we rationally synthesized quite stable gold nanoparticles (AuNPs) using dihydrolipoic acid (DHLA) and DHLA-aspartame (DHLA-Asptm) as both reducing and stabilizing agents in a mixture of water/ethanol at RT under photoirradiation in 10 min. The novelty of this work is that benefiting from both the oxidation of ethanol to ethanal and having the bidentate thiol groups of DHLA, stable DHLA@AuNPs and DHLA-Asptm@AuNPs were successfully and rapidly formed without additional reducing reagents. We systematically examined the formation of DHLA@AuNPs and DHLA-Asptm@AuNPs under different pH values and reaction temperatures. Furthermore, the salt tolerance of DHLA@AuNPs and DHLA-Asptm@AuNPs was tested in a series of sodium chloride solutions. We showed the catalytic and peroxidase-like activities of DHLA@AuNPs against 4-nitrophenol and 3,3 ',5,5 '-tetramethylbenzidine. The AuNPs were characterized by UV-vis spectrophotometry, scanning transmission electron microscopy, zeta potential, and dynamic light scattering.T?rkiye Bilimsel ve Teknolojik Arastirma Kurumu [TUBITAK, 2210-C]; Scientific and Technological Research Council of Turkey [FYL-2022-11694]; Erciyes University Scientific Research Projects OfficeThe project was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) with 2210-C Domestic Priority Areas Master's Scholarship and by Erciyes University Scientific Research Projects Office with the project code FYL-2022-11694
A Functional Barley-Based Fermented Soup (Tarhana) With High Β-Glucan Content
No full textKoksel, Hamit/0000-0003-4150-2413; Tekin Cakmak, Zeynep Hazal/0000-0002-3369-3128;This study investigates the impact of using different flours, including high beta-glucan barley, on the nutritional properties of tarhana. Mineral composition, phenolic content, and antioxidant capacity of tarhana powder samples produced using flours of high beta-glucan hull-less barley (cv. Chifaa; ChF), hull-less barley cv. Yalin (YF), bread wheat cv. Tosunbey (white flour: TWF1 and whole wheat flour: TWF2). Furthermore, in vitro glycemic index (GI), pasting properties, and RVA soup index of their soups were investigated. Tarhana made with Chifaa barley flour (Tar-ChF) exhibited significantly higher levels of key minerals (K, Mg, Ca), beta-glucan and total phenolic content compared to those made with other flours (Tar YF, Tar TWF1, and Tar TWF2). Barley tarhana samples also showed greater antioxidant activity of bound phenolic fractions and lower GI values, indicating a healthier profile. The study highlights the potential of high beta-glucan barley flour to enhance tarhana's nutritional benefits without significantly affecting its sensory properties, such as color and viscosity. This research supports the integration of health-promoting ingredients like barley flour into traditional Mediterranean foods to improve their nutritional quality.PRIMA Foundation (Horizon2020), PRIMA SECTION 1 2020 AGROFOOD VALUE CHAIN IA TOPIC: 1.3.1-2020 [2034]; PRIMA FoundationThe research was supported by PRIMA Foundation, MEDWHEALTH project grant no. 2034
Housing Culture of Yilli in Kayseri: A Habitus-Based Study
No full textBu çalışma, Kayseri'deki yilli (yerli) topluluğunun mekânsal pratiklerini kimlik ve aidiyet perspektifinden ele almakta; konutun kentsel aidiyet ve toplumsal kimliği nasıl şekillendirdiğine odaklanmaktadır. Konut, yalnızca fiziksel bir yapı olarak değil; kültürel sürekliliğin, toplumsal bağların ve aidiyet duygusunun maddi olarak ifade bulduğu bir mekânsal çerçeve olarak değerlendirilmektedir. Analiz, kent ölçeğinden evin iç mekânına kadar uzanan çok ölçekli bir yaklaşım benimseyerek, yilli ailelerin ev içi mekânı kültürel olarak miras alınmış eğilimlere göre nasıl düzenlediklerini incelemektedir. Pierre Bourdieu'nün habitus kavramına dayanan bu kuramsal çerçevede, tarihsel olarak biçimlenmiş pratik ve değerlerin gündelik mekânsal düzenlemelere nasıl gömüldüğü araştırılmaktadır. Bu bağlamda yilli olmak, yalnızca soy bağına ya da mahalle kökenine dayanan bir kimlik değil; konut tercihleri, mahalleye aidiyet ve kuşaklar arası kültürel aktarım yoluyla yeniden üretilen toplumsal olarak konumlanmış bir kimlik biçimi olarak ortaya çıkmaktadır. Bu dinamikler, gündelik rutinlerde, mahremiyet anlayışında ve estetik tercihlerde somutlaşmaktadır. Çalışma, sözlü tarih, etnografik gözlem, mekânsal haritalama ve tematik analiz gibi nitel yöntemlere dayanmaktadır. Farklı kuşaklardan katılımcılarla yapılan görüşmeler, geleneksel evlerden modern apartmanlara geçişin hem bir uyum sürecini hem de kültürel sürekliliği yansıttığını göstermektedir. Bu dönüşümler, teknik değişiklikler olarak değil, toplumsal olarak gömülü süreçler olarak yorumlanmaktadır. Sonuç olarak, bu çalışma yerellik, kimlik ve kentsel belleğin, daha geniş bir kentsel dönüşüm süreci içinde, konut aracılığıyla nasıl yeniden üretildiğini anlamaya yönelik kültürel temelli bir çerçeve sunmaktadır.This study explores the spatial practices of the yilli (local) community in Kayseri through the perspective of identity and belonging, focusing on how housing shapes urban affiliation and social identity. Rather than treating housing as a purely physical structure, it is approached as a spatial framework through which cultural continuity, social ties, and a sense of belonging are materially articulated. The analysis adopts a multi-scalar approach—from the city level to the interior of the house—examining how yilli families organise domestic space according to culturally inherited dispositions. Grounded in Pierre Bourdieu's concept of habitus, the study investigates how historically shaped practices and values are embedded in everyday spatial arrangements. In this framework, being yilli is not simply defined by genealogy or neighbourhood origin. Still, it emerges as a socially situated identity, reproduced through housing choices, neighbourhood affiliation, and intergenerational cultural transmission. These dynamics manifest in daily routines, privacy norms, and aesthetic preferences. Methodologically, the research relies on qualitative tools such as oral history, ethnographic observation, spatial mapping, and thematic analysis. Interviews with participants from multiple generations reveal how the shift from traditional houses to modern apartments reflects adaptation and cultural persistence. These transformations are interpreted not as technical changes, but as socially embedded processes. The study offers a culturally grounded framework for understanding how locality, identity, and urban memory are reproduced through housing within broader urban transformation processes
Discovery and in Silico Characterization of Anatolian Water Buffalo Rumen-Derived Bacterial Thermostable Xylanases: A Sequence-Based Metagenomic Approach
No full textThis study involved shotgun sequencing of rumen metagenomes from three Anatolian water buffalos, an exploration of the relationship between microbial flora and xylanases, and in silico analyses of thermostable xylanases, focusing on their sequence, structure, and dynamic properties. For this purpose, the rumen metagenome of three Anatolian water buffalos was sequenced and bioinformatically analyzed to determine microbial diversity and full-length xylanases. Analyses of BLAST, biophysicochemical characteristics, phylogenetic tree, and multiple sequence alignment were performed with Blastp, ProtParam, MEGA11 software, and Clustal Omega, respectively. Three-dimensional homology models of three xylanases (AWBRMetXyn5, AWBRMetXyn10, and AWBRMetXyn19) were constructed by SWISS-MODEL and validated by ProSA, ProCheck, and Verify3D. Also, their 3D models were structurally analyzed by PyMOL, BAN Delta IT, thermostability predictor, What If, and Protein Interaction Calculator (PIC) software. Protein-ligand interactions were examined by docking and MD simulation. Shotgun sequence and Blastp analyses showed that Clostridium (Clostridiales bacterial order), Ruminococcus (Oscillospiraceae bacterial family), Prevotella (Bacteroidales bacterial order), and Butyrivibrio (Lachnospiraceae bacterial family) were found as dominant potential xylanase-producer genera in three rumen samples. Furthermore, the biophysicochemical analysis indicated that three xylanases exhibited an aliphatic index above 80, an instability index below 40, and melting temperatures (T m) surpassing 65 degrees C. Phylogenetic analysis placed three xylanases within the GH10 family, clustering them with thermophilic xylanases, while homology modeling identified the optimal template as a xylanase from a thermophilic bacterium. The structural analysis indicated that three xylanases possessed the number of salt bridges, hydrophobic interactions, and T m score higher than 50, 165, and 70 degrees C, respectively; however, the reference thermophilic XynAS9 had 43, 145, and 54.41 degrees C, respectively. BAN Delta IT analysis revealed that three xylanases exhibited lower B '-factor values in the beta 3-alpha 1 loop/short-helix at the N-terminal site compared to the reference thermophilic XynAS9. In contrast, six residues (G79, M123, D150, T199, A329, and G377) possessed higher B '-factor values in AWBRMetXyn5 and their aligned positions in AWBRMetXyn10 and AWBRMetXyn19, relative to XynAS9 including Gln, Glu, Ile, Lys, Ser, and Val at these positions, respectively. MD simulation results showed that the beta 9-eta 5 loop including catalytic nucleophile glutamic acid in the RMSF plot of three xylanases had a higher fluctuation than the aligned region in XynAS9. The distance analysis from the MD simulation showed that the nucleophile residue in AWBRMetXyn5 and AWBRMetXyn10 remained closer to the ligand throughout the simulation compared with XynAS9 and AWBRMetXyn19. The most notable difference between AWBRMetXyn5 and AWBRMetXyn10 was the increased amino acid fluctuations in two specific regions, the eta 3 short-helix and the eta 3-alpha 3 loop, despite a minimal sequence difference of only 1.24%, which included three key amino acid variations (N345, N396, and T397 in AWBRMetXyn5; D345, K396, and A397 in AWBRMetXyn10). Thus, this study provided computational insights into xylanase function and thermostability, which could inform future protein engineering efforts. Additionally, three xylanases, especially AWBRMetXyn5, are promising candidates for various high-temperature industrial applications. In a forthcoming study, three xylanases will be experimentally characterized and considered for potential industrial applications. In addition, the amino acid substitutions (G79Q, M123E, D150I, T199K, A329S, and G377V) and the residues in the beta 3-alpha 1 loop will be targeted for thermostability improvement of AWBRMetXyn5. The amino acids (N345, N396, and T397) and the residues on the beta 9-eta 5 loop, eta 3 short-helix, and eta 3-alpha 3 loop will also be focused on development of the catalytic efficiency.Scientific and Technological Research Project Funding Program (1001) of the Scientific and Technological Research Council of Turkiye (TUBITAK) [121Z943]This research was funded by the Scientific and Technological Research Project Funding Program (1001) of the Scientific and Technological Research Council of Turkiye (TUBITAK) (project no.121Z943)
Cinnamomum Zeylanicum Extract Incorporated Electrospun Poly(Lactic Acid)/ Gelatin Membrane as a New Wound Dressing
No full textSen, Alaattin/0000-0002-8444-376XIn this study, we fabricated poly(lactic acid)/gelatin electrospun membranes containing various concentrations of Cinnamomum zeylanicum extract and evaluated them as a novel wound dressing. The electrospun membranes were chemically, morphologically, and mechanically characterized, and the results were discussed in comparison with the literature. Electrospun membranes' biodegradability, swelling, and release properties were evaluated, with the CE7.5 membrane having values of 29.60 f 7.20 and 542.1 f 48.3 % and 66.9 %, respectively. Antibacterial activity was observed in CE7.5 and CE10 membranes against E. coli and S. aureus strains. At the highest concentration (CE10), 111.7 f 5.6 % and 96 f 12.375 % cell viability were detected in fibroblasts and differentiated LPS-induced THP-1 cells. Cell viability was further evaluated by Annexin-V/PI staining, revealing that 97.95 f 1.63 % of the cells remained viable in the CE7.5-treated membranes, while only 1.85 f 1.49 % of necrotic cells were detected in the treated cell population. Fibroblasts treated with the CE7.5 membrane showed a 42 % improvement in wound closure compared to non-treated cells. The anti-inflammatory properties of the electrospun membranes were also investigated. Treatment with the conditioned CE7.5 membrane downregulated Tba1 and tau proteins by 45.1 and 51.055 %, respectively. This study concluded that the newly developed Cinnamomum zeylanicum extract incorporated poly(lactic acid)/gelatin electrospun membranes could be a promising wound dressing material
Microstructural Analysis of Low-Calcium Fly Ash-Based Geopolymer Concrete With Different Ratios of Activator and Binder Under High Temperatures
No full textOzbayrak, Ahmet/0000-0002-8091-4990; Kucukgoncu, Hurmet/0000-0001-5148-8753Geopolymer concretes have emerged as an alternative to traditional Portland cement concretes with high strength, good durability, well corrosion performance and high-temperature resistance, and being a sustainable and environmentally friendly material. In this study, a comprehensive microstructural analysis of low-calcium fly ash-based geopolymer concrete samples with different alkali activator to binder ratios was conducted after exposure to temperatures ranging from 400 to 800 degrees C. The experimental results of the geopolymer concrete specimens found out significant findings, including a notable loss of mass and an approximate 80% decrease in compressive strength after exposure to 800 degrees C. The microstructural analysis underlined crack formation, voids and porosities in the geopolymer matrix at elevated temperatures, affecting the physical and mechanical properties of the material. The study presents significant insights into the behaviour of low-calcium fly ash-based geopolymer concrete with different binder and alkali activator ratios under high temperatures, revealing the performance of geopolymer concretes in extreme environments and the effect of incompatibility between geopolymer concrete and aggregate due to thermal temperature effects on this performance.TUBITAK (The Scientific and Technological Research Council of Turkey) [121M236]This research project was funded by TUBITAK (The Scientific and Technological Research Council of Turkey) with grant number 121M236. The authors extend their gratitude to the other researchers who contributed to the study