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A Novel Bifunctional Organic Supported Nano-Titania Photocatalyst via the Sol-Gel Method Using Walnut-Shell
No full textErdem, Ilker/0000-0001-5743-0835Nano-structured photocatalytic titania was prepared via the sol-gel method on the surface of carbon-rich organic support in situ to be used as a supported photocatalyst. The preparation process was lean, including sol preparation, mixing and calcination (450 degrees C). The microstructure and crystallinity were characterized by using SEM and XRD analysis. The prepared photocatalytic material shows better water clarification (dye removal) efficiencies than commercial nano titania, either excited by UV or visible light, or kept in the darkness. A bifunctional composite having both photocatalysis and adsorption capabilities simultaneously was prepared using walnut shell (WNS) as organic support for the first time. It has considerably higher dye removal rates (kapp values (min(-1))) when compared with commercial nano titania: 0.1827 (2.83 times higher), 0.1188 (9.35 times higher) and 0.1066 (12.25 times higher) under UV light, under visible light, and in the darkness, respectively, making it a promising candidate for water clarification processes.Research Fund of the Abdullah Gul University [FBA-2017-93]This study has been supported by Research Fund of the Abdullah Gul University (Project Number: FBA-2017-93)
Neuroinflammatory Human Brain Organoids Enable Comprehensive Drug Screening Studies: Fingolimod and Its Analogues in Focus
No full textIntroduction The absence of physiologically relevant models for neuroinflammatory brain disorders, such as multiple sclerosis (MS), highlights the need for improved drug screening platforms. To bridge this gap, this study aimed to develop a human brain organoid (hBO) model incorporating essential neural cell types, including astrocytes, microglia, and oligodendrocytes.Methods hBOs were generated from H9 stem cells, and neuroinflammatory characteristics were elicited by lipopolysaccharide (LPS). The expression of specific neuronal and inflammatory markers was assessed through qRT-PCR, immunofluorescence staining (IFS), and ELISA.Results IFS of mature hBOs with anti-SOX2, anti-SATB2, anti-MAPT, anti-GFAP, anti-MBP, and anti-IBA1 antibodies and images collected with the confocal microscope confirmed the differentiation of H9 cells into cortical neurons, astrocytes, microglia, and oligodendrocyte cell types. Elevated GFAP, IBA1, NF-kappa B, and IL-6 levels, along with reduced CNPase expression with LPS treatment, were considered reflective of MS-like pathology and were used to test fingolimod and its derivatives. Fingolimod and all its derivatives, specifically ST-1505, decreased MAPT (2.1-fold in ELISA, 1.7-fold in IFS), GFAP (1.8-fold in IFS), TNF alpha (5.4-fold in qRT-PCR), and FABP (1.5-fold in ELISA) levels, and increased IL-10 (11-fold in qRT-PCR) and MBP (2.9-fold in IFS) levels.Discussion The present data collectively showed LPS to evoke neuroinflammation in the hBO model, while fingolimod and its derivatives, particularly ST-1505, exhibited significant anti-inflammatory and neuroprotective properties by counteracting these evoked changes in the hBO model.Conclusion The findings supported the applicability of brain organoids as a model system for drug screening studies for neuroinflammatory brain diseases.Scientific and Technological Research Council of Turkiye (TUBITAK) [119Z389]This work was supported by grants from the Scientific and Technological Research Council of Turkiye (TUBITAK 119Z389)
Does Your Love Lift Me Higher? A Direct Replication of the Energising Role of Secure Relationships
No full textPrevious work has revealed that priming people with significant others increases feelings of security and energy, and in turn, boosts exploration motivations. In this preregistered study, we directly replicated Luke et al.'s (2012) Study 2 (N = 281). We found similar results as the replicated study regarding increased security feelings and exploration motivations on the self-report measures after the priming. However, we did not find any support for the increased energy feelings after the attachment security priming. In addition, contrary to Luke et al.'s (2012) results, energy feelings did not mediate the relationship between security priming and exploration motivations. A discussion of null findings, along with the limitations of self-reports and potential misinterpretation of the mediational analyses, follows. We also discuss possible future implications of the current findings. © 2025 International Union of Psychological Science
Tuning Properties of Amorphous Boron Via Hydrogenation: An Ab Initio Study
No full textAb initio simulations are employed to investigate the structural, mechanical, and electronic properties of hydrogenated amorphous boron (a-B:H) across a range of hydrogen concentrations (approximate to 6-21 at.%). The results indicate that pentagonal-like boron clusters constitute the primary structural motifs. The bonding environment consists of both B-H terminal bonds and B-H-B bridging bonds, with the fraction of bridging bonds ranging from 10 % to 16 %. Increasing the hydrogen content leads to a reduction in density and bulk modulus, accompanied by a systematic widening of the electronic band gap. These results demonstrate that hydrogen incorporation profoundly modifies the atomic structure, softens the network, and enhances the semiconducting character of a-B:H, highlighting the tunability of properties in boron-based amorphous materials.Abdullah Gul University Support FoundationThe author extends gratitude to the Abdullah Gul University Support Foundation for their support. The author acknowledges the computing resources and time generously provided by TUBITAK ULAKBIM High Performance and Grid Computing Center (TRUBA resources)
Numerical Analysis and Experimental Comparison of Stress and Stiffness Parameters of Steel Reinforced Geopolymer Concrete Columns
No full textDespite extensive research, Geopolymer concrete (GPC) lacks reinforced concrete construction and design specifications. Developing such specifications requires comprehensive studies to promote the use of GPC, which is known for its superior performance and environmental benefits compared to ordinary Portland cement concrete (OPC). This study numerically investigated and compared the behavior and strength of fly ash-based geopolymer-reinforced concrete columns with the experimental results. Comparisons with OPC were made based on existing specifications. Herein, FEM analyses were conducted on 16 GPC and 4 OPC columns under eccentric axial compressive loads. Parameters such as eccentricity, reinforcement ratio, curing method, and activation solution ratios were varied. According to average numerical results, the GPC columns have 7% more moment capacity and 30% more curvature values than OPC. Moreover, GPC columns absorbed more energy than OPC columns. Also, GPC columns have higher axial load and bending moment carrying capacities than OPC for numerical results. Error analysis between FEM and experimental data revealed a strong correlation, with MAPE values of 8.88% (axial load) and 7.20% (moment) for GPC columns, confirming the reliability of the numerical model. ACI 318 and Eurocode 2 specifications were deemed applicable for GPC columns, provided axial loads are limited per TEC 2018.TUBITAK (The Scientific and Technological Research Council of Tuerkiye) [121M236]This research was supported by TUEBITAK (The Scientific and Technological Research Council of Tuerkiye) under Grant Number 121M236. We would like to thank the Proofreading & Editing Office of the Dean for Research at Erciyes University for the copyediting and proofreading service for this manuscript
Vim-Polyp: Multimodal Colon Polyp Dataset with Video, Histopathology, and Protein Expression
No full textThe 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.Trkiye Bilimsel ve Teknolojik Arastirma Kurumu (Scientific and Technological Research Council of Turkey) [120E204]This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK 1001), Turkiye, under Grant 120E204. This work was derived from the corresponding author Refika Sultan Do & gbreve;an Ph.D. thesis' Artificial Intelligence Assisted Prognostic Marker Determination from Colonoscopy and Histopathology Images for Colon Polyps, 2023'51. Additionally, the valuable contributions of the Kayseri City Hospital Gastroenterology and Pathology Departments to this study are sincerely appreciated. The authors are grateful to Gulf University for Science and Technology (GUST), Kuwait, for covering the APC for this paper, enabling its publication
Unhappiness Among the Unemployed: The Roles of Descriptive Norms, Injunctive Norms and Personal Beliefs
No full textUgur, Zeynep B./0000-0002-5141-2529This study explores the influence of social norms and individual beliefs on the well-being of unemployed individuals in Turkey, a context marked by both chronic unemployment and a high societal valuation of employment. Using province-level representative data from the 2013 Life Satisfaction Survey, encompassing 196,203 observations, we analyse how descriptive norms (prevalence of unemployment) and injunctive norms (social pressures due to unemployment) at the province level affect the happiness of the unemployed. We utilized people's perception of employment for being respected in social life and personally feeling social pressure as a measure of individual beliefs. Multilevel regression results reveal that descriptive norms can modestly alleviate the adverse impact of unemployment, particularly for the short-term unemployed, while injunctive norms slightly intensify the unhappiness of being unemployed, especially in the short term. The unemployed's personal beliefs about the value of employment matter for their happiness. These findings underscore the theoretical implications of social norms in shaping the well-being of the unemployed and highlight the importance of individual beliefs in moderating these effects.Coordination Office for Scientific Research Projects of Social Sciences University of Ankara [SBF-2022-202]the Coordination Office for Scientific Research Projects of Social Sciences University of Ankara, Grant/Award Number: SBF-2022-20
Structural Behavior of Geopolymer Reinforced Concrete Beams: Experimental, Numerical, and Code-Based Assessment
No full textThis study experimentally investigates the flexural performance of heat-cured low-calcium fly ash-based geopolymer concrete (GPC) beams reinforced with ribbed steel bars, focusing on the effects of reinforcement ratio, alkaline activator concentration (SS/SH), and curing regime. Fifteen full-scale beams, including twelve GPC and three OPC specimens, were tested under four-point loading to evaluate load-deflection and moment-curvature behavior. Despite a lower compressive elastic modulus, the results showed that GPC beams exhibited comparable or superior cracking and ultimate moment capacities relative to OPC beams. Increasing the reinforcement ratio enhanced load capacity but reduced ductility in both systems, with GPC beams showing more brittle post-yield behavior. Numerical models based on OPC parameters were developed in SAP2000 to compare with experimental GPC moment-curvature data, revealing good agreement in the linear range but notable differences in post-yield response. The study also examined the microstructure of failed GPC beams via SEM, XRD, and EDX analyses to correlate matrix morphology with mechanical behavior. Finally, moment capacities calculated according to ACI 318 and TS 500 provided conservative estimates, supporting the safe applicability of current design codes to heat-cured GPC beams. These findings demonstrate that GPC, when properly proportioned and cured, is a viable structural alternative to OPC for reinforced concrete members.TUBITAK (The Scientific and Technological Research Council of Turkiye) [121M236]This research was supported by TUBITAK (The Scientific and Technological Research Council of Turkiye) under grant number 121M236
A Digital 'Smiley Analysis of the Appreciation for Tourist Amenities by Visitors to London
No full textKourtit, Karima/0000-0002-7171-994X; Osth, John/0000-0002-4536-9229; Nijkamp, Peter/0000-0002-4068-8132Digital wellbeing research is on a rising edge. It is also increasingly applied in the hospitality sector to measure the satisfaction of visitors (metaphorically called here 'smileys'); understanding and enhancing visitor satisfaction are pivotal for the success of tourism destinations. This study seeks to identify critical factors influencing the visitors' appreciation for London, a city renowned for its allure, by harnessing available user data from Airbnb listings and hotels, using online reviews, with a particular view to the spatial pattern of visitors' choices in corona times. Advanced statistical techniques, including sentiment analysis, digital text analysis, multilevel analysis, and geographically weighted regression, are employed to discover geographical patterns as well as statistical correlations between land use, density, geographic location, and visitor contentment. The findings reveal that proximity to parks, accessibility to public transportation, and the presence of natural amenities exert substantial influence on visitor satisfaction in London. Especially, the proximity to a park enhances visitor satisfaction, predominantly in western London. Efficient access to public transportation in central areas of the city positively impacts visitor contentment levels as well. Furthermore, the availability of and accessibility to natural attractions in the southern and southwest areas of London appear to elevate visitor satisfaction. These novel insights empower destination managers, policymakers, and tourism stakeholders to make informed decisions, formulate targeted strategies, and enhance visitor experiences in specific London locales. The research highlights the importance of considering location-specific factors and customizing approaches to optimize the visitor appreciations for a city. By understanding the complex dynamics between land use, density, location, and visitor satisfaction, stakeholders can foster sustainable tourism growth and create a more appealing environment for visitors.HORIZON-CL2-2022-TRANSFORMATIONS-01 Programme [HORIZON-CL2-2022-TRANSFORMATIONS-01, 101094546]Karima Kourtit acknowledges funding from the HORIZON-CL2-2022-TRANSFORMATIONS-01 Programme, under grant agreement No. 101094546
Highly Potent New Probiotic Strains From Traditional Turkish Fermented Foods
No full textTraditional Turkish fermented foods like boza, pickles, and tarhana are recognized for their nutritional and health benefits, yet the probiotic potential of lactic acid bacteria (LAB) strains isolated from them remains underexplored. Sixty-six LAB strains were isolated from fermented foods using bacterial morphology, Gram staining, and catalase activity. The isolates were differentiated at strain level by RAPD-PCR (Random Amplification of Polymorphic DNA-Polymerase Chain Reaction) and twenty-five strains were selected for further evaluation of acid and bile salt tolerance. Among these, ten strains exhibited high tolerance and were subsequently assessed for adhesion to Caco-2 colorectal carcinoma cells, antimicrobial activity, exopolysaccharide (EPS) production, lysozyme resistance, and hemolytic activity. Using k-means clustering, three strains: Lactiplantibacillus plantarum ES-3, Pediococcus pentosaceus N-1, and Enterococcus faecium N-2 demonstrated superior probiotic characteristics, including significant acid (100% survival at pH3.0) and 0.3% bile salt tolerance (57%, 64%, 67%), strong adhesion to intestinal cells (65%, 88%, 91%), high lysozyme resistance (88%, 88%, 77%), and produced high amounts of EPS. These strains show promising potential as probiotics and warrant further investigation to confirm their functional properties and potential applications.Abdullah Gul UniversityThe authors would like to thank Abdullah Gul University for support, and Muhammet Fatih Polat, Burak Cal & imath;& scedil;, and Hale Nur Ayayd & imath;n for their help in the isolation of lactic acid bacteria