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Experimental and Numerical Analysis of Damage and Crack Behavior in Geopolymer and Ordinary Portland Cement Reinforced Concrete Columns
No full textThis study evaluates and compares the structural behavior of reinforced concrete columns produced with geopolymer concrete (GPC) and ordinary Portland cement (OPC) under eccentric axial loading, aiming to investigate GPC's potential as a sustainable alternative. A total of twenty columns with varying longitudinal reinforcement ratios, curing methods, eccentricities, and geopolymer formulations were experimentally tested. Displacement measurements at each load increment were obtained using a total station, allowing crack pattern tracking at key stages such as first cracking, yielding, and ultimate failure. These observations were schematically documented using AutoCAD. Additionally, finite element models were developed in ABAQUS using the Concrete Damage Plasticity (CDP) model, with material parameters calibrated based on experimental compressive and tensile strengths, elastic modulus, and fracture energy. Results indicated that increasing eccentricity reduces axial load capacity while increasing lateral deformation. While the reinforcement ratio did not significantly affect axial strength, it increased displacement demand. Due to their distinct microstructural characteristics, GPC columns exhibited greater deformation capacity and narrower, more localized crack patterns than OPC columns. Furthermore, the sodium silicate/sodium hydroxide (SS/SH) ratio and curing duration significantly influenced the structural response of GPC. Numerical simulations showed strong agreement with experimental results regarding load-displacement behavior and damage distribution. These findings demonstrate that GPC can serve as a reliable and sustainable alternative to OPC in structural column applications, provided its specific material properties are considered in design and analysis.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. We would like to thank the Proofreading & Editing Office of the Dean for Research at Erciyes University for copyediting and proofreading service for this manuscript
A Homozygous Frameshift Variant in the CILK1 Gene Causes Cranioectodermal Dysplasia
No full textSezer, Abdullah/0000-0003-3886-3808Cranioectodermal dysplasia (CED) is a ciliopathy characterized by skeletal and ectodermal abnormalities, renal failure, and liver fibrosis. Pathogenic variants in genes that encode the intraflagellar transport (IFT) complex components, particularly IFT-A, are responsible for approximately two-thirds of the CED cases. However, the cause of the remaining cases remains unknown. Ciliogenesis-associated kinase 1 (CILK1) is a highly conserved ciliary serine/threonine kinase with an N-terminal catalytic domain responsible for kinase activity and a C-terminal non-catalytic domain that interacts with the IFT-B complex. Biallelic variants in the catalytic domain are associated with lethal skeletal dysplasia, endocrine cerebroosteodysplasia, and short-rib polydactyly syndrome. No human disease has been linked to biallelic variants in the non-catalytic domain. We present a homozygous frameshift variant in the CILK1 gene that affects the distal part of the non-catalytic domain, causing CED in five patients from two pedigrees. All the patients survived into childhood and had disproportionately short stature, skeletal abnormalities, ectodermal dysplasia, renal issues, and liver complications. Functional data from patient-derived cells and the C. elegans model indicate that the variant reduces cilia number, increases cilia length, and disrupts the localization of IFT components. In contrast, the ciliary localization of CILK1 bearing the variant itself remains unaffected. Notably, we rescued the majority of these abnormalities by reintroducing CILK1 into patient-derived cells. Finally, our study describes CILK1 as a novel causal gene and the first non-IFT protein-encoding gene in the etiology of CED, thus expanding the known genotypic, mechanistic, and phenotypic spectrum of CED.Gazi University Scientific Research Projects Coordination Unit (BAP) [TCD-2022-7772]; Scientific and Technological Research Council of Turkiye (TUBIdot;TAK)This work was supported by Gazi University Scientific Research Projects Coordination Unit (BAP) Grant TCD-2022-7772 (to MAE). Open access funding provided by the Scientific and Technological Research Council of Turkiye (TUB & Idot;TAK)
Patient Experiences of Behavioural Therapy for Bipolar Depression: A33 Qualitative Study
No full textYilmaz, Sakir/0000-0003-1896-1742; Hancox, Anna/0000-0002-8211-3134BackgroundAlthough multiple qualitative studies have explored participants' experiences of behavioural activation (BA) for unipolar depression, none have investigated the experiences of BA in people with bipolar depression. This is of particular interest because qualitative studies concerning the experience of receiving therapy can help inform the theory of change underpinning the intervention.AimThe purpose of this study was to explore the experiences and perspectives of individuals with bipolar disorder who received a course of one-to-one BA for bipolar depression. We sought to explore participants' experience of the effects of BA therapy, both proximally and distally.MethodSemi-structured interviews were conducted with nine individuals meeting research diagnostic criteria for bipolar I or II disorder who had received up to 20 sessions of BA adapted for bipolar depression. Thematic analysis using a framework approach was used to explore and describe the experiences of participants.ResultsParticipants' perspectives on the impact of therapy were categorized under four subthemes: client behaviour inside and outside sessions, changes in clients' perspectives, the impact on symptoms and impact on life and functioning.ConclusionsParticipants' accounts of the impact of therapy were broadly consistent with the theory underpinning a behavioural approach. Participants described a central role for perspective change, and particularly increased acceptance of the self and mood states, as facilitating behavioural changes and more distal benefits. Process evaluations embedded in future trials may include quantitative measures of key processes described by our participants, as well as those clearly implied by the behavioural theory of depression.Ministry of National Education of TurkeyThis study is partly supported by the Ministry of National Education of Turkey
Stimuli-Responsive and Self-Assembled Sericin Materials for Various Applications
No full textThe silkworm cocoon's structural integrity is maintained by sericin, which acts as a sticky binding layer that envelops the fibroin fibers, effectively holding them together. In the silk industry, sericin is removed from the structure of fibroin during the degumming process in order to provide the silk's whiteness, softness, and smoothness and also to make it dyeable. Sericin, which is separated from the fibroin of the cocoon by the degumming process in the textile industry in the production of silk fabric, is discarded as waste material. This waste helps cell attachment, proliferation, and differentiation in sericin-based materials, owing to its biocompatibility, biodegradability, and bioactivity features. Due to all these specific features, sericin protein is involved in the production of various biomaterials such as films, hydrogels, scaffolds, conduits, fibers, and devices used in tissue engineering and regenerative medicine. © 2025 Elsevier B.V., All rights reserved
Bright Green and Blue Solid-State Emitting Carbon Dots with Optimized Photoluminescence Characteristics for Fabrication of High-Performance Light Emitting Diodes
No full textLuminescent carbon dots (CDs) possess a range of fundamental and technological advantages, including low-cost, and scalable preparation methods, high emission efficiency, tunable electronic properties, and adaptable surface characteristics. However, aggregation-caused quench in solid-state emission of CDs has constrained their applications in luminescent solar-concentrators, and light-emitting devices. This study introduces a rapid and straightforward microwave method for producing bright blue-and green-emissive CDs, with emission peaks at 440 nm and 520 nm, respectively. Blue-CDs showed excitation-dependent feature with a biexponential decay profile and average lifetime of 6.3 ns, while the green one signified an excitation-independent photoluminescence profile with longer average lifetime of 9 ns through biexponential fitting of decay plot. Upon optimization of experimental parameters, reproducible green emission with a high efficiency of 78 % was achieved in dimethyl sulfoxide (DMSO). The critical role of biurea as a nitrogen precursor was elucidated through experimental and computational investigations. Furthermore, owing to the bright solid-state emission of the synthesized CDs, they were utilized as color-converting layers in the fabrication of durable monochrome LEDs, yielding blue and yellowish-green emissions with Commission Internationale de L'Eclairage (CIE) coordinates of (0.16, 0.10) and (0.35, 0.57), respectively. This study highlights the potential of CDs for applications in light-emitting panels.Iran National Science Foundation (INSF) [4013040]; National Natural Science Foundation of China [12261141661]The R.S. and E.S. would like to acknowledge funding support received from the Iran National Science Foundation (INSF) with the Grant Number of 4013040. Also, Q.L. and C -X. S. gratefully acknowledged the support of this research by the National Natural Science Foundation of China (12261141661)
Afet Sonrası İletişim için UAV Tabanlı Mobil Baz İstasyonlarında Görev Atama ve Enerji Optimizasyonuna Yönelik Bir Planlama Modeli
No full textDoğal afetlerin ardından haberleşme altyapısının sürdürülebilirliğini sağlamak hayati öneme sahiptir. Üzerlerinde baz istasyonu teknolojisi bulunan İnsansız Hava Araçları (İHA'lar), afet bölgelerinde bağlantıların kurulmasını mümkün kılmaktadır. İHA'ların hareket kabiliyetleri, kapsama yetenekleri ve havada uzun süre kalabilmeleri gibi avantajları bulunsa da; batarya ömrü, olumsuz hava koşulları ve değişken afet ortamları gibi faktörler bu sistemlerin sahadaki etkinliğini kısıtlamaktadır. Bu tez çalışması İHA tabanlı mobil baz istasyonlarının konumlandırılması ve enerji ikmali süreçlerinin optimizasyonunu hedefleyen bir Karma Tamsayılı Doğrusal Programlama (MILP) modeli önermektedir. Modelde nüfus yoğunluğu ve afet etki şiddeti dikkate alınarak talep değerleri dinamik biçimde belirlenmekte; batarya sınırlamaları ve şarj altyapısı gibi kısıtlar entegre edilmektedir. Altıgen grid temelli bir mekânsal yapı kullanılarak kentsel alanlarda kapsama performansı en üst düzeye çıkarılmaktadır. Model, GAMS ile uygulamaya alınmış ve vaka çalışması ile test edilmiştir. İHA sayıları, konuşlanma noktaları ve şarj istasyonu senaryoları kullanılarak simülasyonlar gerçekleştirilmiştir. Elde edilen sonuçlar, modelin enerji verimliliğini koruyarak yüksek kapsama sağlayan etkin konuşlanma planları oluşturabildiğini göstermektedir. Ayrıca, büyük ölçekli uygulamalarda modelin çözüm sürelerinin önemli ölçüde arttığı gözlemlenmiştir. Bu durum, gerçek zamanlı kullanım için sezgisel ve meta-sezgisel algoritmaların entegrasyonunun gerekliliğini ortaya koymaktadır. Bu çalışma, İHA'ların afet sonrası iletişimde etkin kullanılabilmesi için özgün bir optimizasyon yaklaşımı sunmakta ve teorik modelleme ile pratik konuşlanma stratejileri arasında köprü kurarak hem akademik literatüre hem de afet yönetimi uygulamalarına anlamlı bir katkı sağlamaktadır.Ensuring the sustainability of communications infrastructure following natural disasters is of vital importance. Unmanned Aerial Vehicles (UAVs), equipped with base station technologies, provide that enables connectivity in disaster zones. While UAVs offer key advantages such as mobility, coverage, and prolonged airtime, their effective use in real-world scenarios is often constrained by operational factors such as battery capacity, adverse weather conditions, and dynamic disaster environments. This study introduces a Mixed-Integer Linear Programming (MILP) model designed to optimize the positioning and energy replenishment of UAV-based bases. The model incorporates dynamic user demand based on population density and disaster impact severity, battery limitations, and charging logistics. A hexagonal grid-based spatial framework is employed to maximize coverage in complex urban landscapes. The model is implemented using GAMS and its performance is evaluated through a case study, using district-level demographic and risk data. Scenarios are used to test the proposed solution method by varying the number of UAVs, deployment sites, and available charging stations. The results demonstrate the model's capability to produce effective and energy-efficient UAV assignment plans that significantly improve post-disaster communication coverage. Furthermore, the findings reveal that although the model performs well under moderate-scale conditions, execution times increase considerably in large-scale scenarios. This limitation suggests the necessity of integrating heuristic and metaheuristic approaches in future work to enhance real-time responsiveness and scalability. Overall, this study contributes a novel optimization framework that bridges theoretical modeling and practical deployment strategies, reinforcing the critical role of UAVs as not only a technological solution but also a humanitarian asset in disaster response systems
High-Resolution DIC Analysis of in Situ Strain and Crack Propagation in Coated AZ31 Magnesium Alloys Under Mechanical Loading
No full textBlunn, Gordon/0000-0003-2141-7385; Yavuzyegit, Berzah/0000-0003-0759-780X; Bonithon, Roxane/0000-0002-4252-0894Biodegradable magnesium (Mg) alloys are promising for various biomedical applications but their susceptibility to corrosion poses significant challenges. This study systematically examines the microstructural integrity and failure mechanisms of electrochemically deposited phosphate- and fluorine-rich coatings on AZ31 Mg alloy subjected to three-point bending (3 PB) in both non-corrosive and physiological (HBSS) environments. High-resolution digital image correlation (HR-DIC) combined with scanning electron microscopy (SEM) enables in situ visualization and quantitative analysis of crack initiation, evolution, and propagation within the coatings. Our findings reveal that thinner (5 mu m) coatings are prone to forming dense networks of fine cracks, while thicker (15 mu m) coatings display fewer but wider cracks, with both morphologies strongly governed by localized shear strain. Importantly, cross-sectional analyses after load-holding demonstrate that, while surface cracks initially remain confined within the coating, cracks generated under higher mechanical loading can propagate through the entire coating thickness. These through-thickness cracks create direct pathways for corrosive fluids to access the underlying alloy, serving as initiation sites for stress corrosion cracking within the substrate. Furthermore, our results indicate that fluoride in the coating mitigates rapid corrosion. Overall, the study reveals that coating failure and the formation of through-thickness cracks play a critical role in facilitating localized corrosion and crack initiation within the alloy under combined mechanical and corrosive environments.Innovate UK [10025764]; Innovate UK; University of PortsmouthThis work was supported by Innovate UK [10025764]. We gratefully acknowledge Geoff Britton, Colin Lupton, and Joseph Dunlop for technical assistance from the University of Portsmouth
A Comprehensive MicroRNA-seq Transcriptomic Analysis of Tay-Sachs Disease Mice Revealed Distinct miRNA Profiles in Neuroglial Cells
No full textTay-Sachs disease (TSD) is a rare lysosomal storage disorder marked by the progressive buildup of GM2 in the central nervous system (CNS). This condition arises from mutations in the HEXA gene, which encodes the alpha subunit of the enzyme beta-hexosaminidase A. A newly developed mouse model for early-onset TSD (Hexa-/-Neu3-/-) exhibited signs of neurodegeneration and neuroinflammation, evidenced by elevated levels of pro-inflammatory cytokines and chemokines, as well as significant astrogliosis and microgliosis. Identifying disease-specific MicroRNAs (miRNAs) may aid the development of targeted therapies. Although previous small-scale studies have investigated miRNA expression in some regions of GM2 gangliosidosis mouse models, thorough profiling of miRNAs in this innovative TSD model remains to be done. In this study, we employed next-generation sequencing to analyze the complete miRNA profile of neuroglial cells from Hexa-/-Neu3-/- mice. By comparing KEGG and Reactome pathways associated with neurodegeneration, neuroinflammation, and sphingolipid metabolism in Hexa-/-Neu3-/- neuroglial cells, we discovered new MicroRNAs and their targets related to the pathophysiology of GM2 gangliosidosis. For the first time, our findings showed that miR-708-5p, miR-672-5p, miR-204-5p, miR-335-5p, and miR-296-3p were upregulated, while miR-10 b-5p, miR-615-3p, miR-196a-5p, miR-214-5p, and miR-199a-5p were downregulated in Hexa-/-Neu3-/- neuroglial cells in comparison to age-matched wild-type (WT). These specific changes in miRNA expression deepen our understanding of the disease's neuropathological characteristics in Hexa-/-Neu3-/- mice. Our study suggests that miRNA-based therapeutic strategies may improve clinical outcomes for TSD patients.Scientific and Technological Research Council of Turkiye (TUBITAK) [221Z118]This research was supported by the Scientific and Technological Research Council of Turkiye (TUBITAK, Project number: 221Z118)
The Trajectory of ‘tanpınar Studies’ From Post-Kemalism To Global Tanpınar
No full textTanpınar holds a pivotal place in Turkish literature, shaping debates on Turkey's history. This article traces his critical reception from post-Kemalist readings to global interpretations. In the 1980s, he was central to post-Kemalist critiques of modernization; later, his works were reinterpreted through global modernity. Global Tanpınar teaches us two lessons: intellectually, it calls for a post-post-Kemalist perspective that situates Turkey's historical experience within the context of global crises. Culturally, it advocates a policy that goes beyond the traditional East-West synthesis and ‘standard’ multiculturalism by transcending the essentialist dichotomies that underpin global inequalities. © 2025 Informa UK Limited, trading as Taylor & Francis Group
Synthesis, Characterization, and Comprehensive in Vitro and in Silico Evaluation of the Anti-Inflammatory Potential of Novel 1,2,3-Triazole-Arylidenehydrazide/Thiazolidinone Hybrids
No full textFive novel 1,2,3-triazole/arylidenehydrazide/thiazolidinone hybrid compounds (7-11) were synthesized and characterized using NMR, HRMS, IR, and HPLC purity analysis. The cytotoxicity of these compounds was evaluated on fibroblasts and THP-1 cells, showing that all compounds were nontoxic at the tested concentrations. The wound healing assay revealed that compounds 7, 9, and 10 significantly enhanced wound closure, with a 7.74%-32.69% improvement in treated cells. Compounds 8 and 11 showed moderate effects. Anti-inflammatory activity was assessed through qRT-PCR, demonstrating that compound 10 led to the most significant reduction in proinflammatory cytokines TNF-alpha, IL-1 beta, and NF-kappa B1. In addition, the expression of Iba1 protein in THP-1 cells confirmed that compound 8 showed the strongest anti-inflammatory effect, surpassing that of aspirin. Compound 10 showed the highest inhibition of NF-kappa B signaling and iNOS activity. Molecular docking studies revealed that compounds 10 and 11 had strong binding affinities to TNF-alpha and iNOS, with compound 11 showing the most stable interactions. Molecular dynamics simulations supported these findings, indicating that compound 11 demonstrated more stable binding to both targets. Overall, the results suggest that compounds 10 and 11 are promising anti-inflammatory candidates with potential for further development in therapeutic applications for inflammatory diseases.The authors received no specific funding for this work. Funding Source: MedlineThe authors have nothing to report