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Polarisation Over the Meaning of Democracy: The Case of Political Parties in Turkey
No full textAkboga, Sema/0000-0003-0937-9961; Sahin, Osman/0000-0002-0815-9433As the primary means of political organisation, political parties remain vital to contemporary democracies, making it important to investigate their understanding of democracy. This study explores the themes with which five largest political parties in Turkey associate democracy. We studied tweets posted by official accounts of these parties' headquarters and branches, as well as by other Twitter accounts that are institutionally linked to these parties. We found significant differences between the government bloc and the opposition bloc as well as between People Alliance and Nation Alliance in terms of the themes with which they associate democracy. The government bloc and People Alliance use themes such as national will and military coups while referring to democracy. The opposition bloc and Nation Alliance emphasise themes such as equality, freedom of the press, and justice. We conclude that parties' and blocs' different attitudes towards democracy are indicators of political polarisation in Turkey
Hosting Capacity Calculation Methods
No full textIn this chapter, we focus on hosting capacity (HC) calculations, by giving the methods to determine the maximum amount of distributed energy resources (DER) that can be integrated into power distribution network(s) without compromising reliability or performance. We detail methodologies such as power flow-based approaches, probabilistic techniques, and machine learning algorithms, with sample applications of HC calculations. Initially, we focus on power flow-based methods based on simulating power distribution network(s) to assess system voltage, current flow, and stability impacts from DER installations. Then, we will give the probabilistic approaches that use uncertainties in renewable generation and consumer demand, based on statistical techniques and Monte Carlo simulations aiming to reflect these variability. Machine learning (ML) techniques will also be given based on analyzing large data sets, detecting patterns, and predicting system responses. These kinds of methods include regression analysis and neural networks trained on historical data for optimized HC predictions. It should be stated that HC is impacted by several factors, such as network topology, load profiles, and DER characteristics, and these as well will be discussed. We will provide a practical example of an HC calculation on a 141-node distribution network using a step-by-step algorithm in Matpower, with simulation results based on an iterative deterministic method. Then, we will give the broader implications of HC assessments for grid modernization and energy policy, highlighting how accurate calculations support a more decentralized, sustainable, and resilient energy future. © 2025 Elsevier B.V., All rights reserved
Study on Single Sided Comb Shaped Patch Antennas With Arm Rotation Allowing Resonant Frequency Shift and Pattern Pivoting Adaptable for Sensing Operations
No full textIn this paper single sided comb shaped patch antennas having different number of arms with various arm rotations are reported. With simulations S11 parameter changes and the far-field radiation patterns of the antennas are calculated. Results show that the first and the second resonances of the designed antennas shift to higher frequencies and their patterns pivot in certain directions as the antenna arms rotate. Among the designed antennas, the antennas having three arms on the side with different arm rotations are manufactured, too. Measured Sii parameter change results agree well with the simulation results. The findings indicate that the designed antennas are promising for size critical systems as well as sensing operations
Engineering a Bilayered Scaffold as a Potential Cardiac Patch: From Scaffold Design to in Vitro Assessment
No full textIn this study, we developed a novel bilayered scaffold consisting of a bottom layer composed of the Decellularized Bovine Pericardium (DP) coated with Polyaniline Nanoparticles (PANINPs) and a top layer made of an electrospun Poly(lactic-co-glycolic acid)/Gelatin (PLGA/Gel) membrane incorporated with Vascular Endothelial Growth Factor (VEGF) and hawthorn extract. Functionally, the DP supplies native Extracellular Matrix (ECM) components and mechanical support, while PANINPs provide conductivity. The electrospun PLGA/Gel layer mimics fibrous ECM. It incorporates bioactives, with VEGF promoting pro-angiogenic stimulation and hawthorn extract enhancing anticoagulant activity, as well as increasing surface hydrophilicity. The tissue adhesive ensures the interfacial integrity between the two layers. Decellularization efficiency was confirmed histologically using 4 ',6-diamidino-2-phenylindole (DAPI) and Hematoxylin-Eosin (H&E) staining. The DP exhibited a DNA content of 115.9 +/- 47.8 ng/mg DNA, compared to 982.88 +/- 395.42 ng/mg in Native Pericardium (NP). The PANINPs had an average particle size of 104.94 +/- 13.7 nm. The conductivity of PANINPs-coated decellularized pericardium was measured to be 9.093 +/- 8.6 x 10- 4 S/cm using the four-point probe method. PLGA/Gel membranes containing hawthorn extract (1%, 5%, 10%, and 15% w/v) and VEGF (0.1 mu g/mL, 0.5 mu g/mL, and 1 mu g/mL) were fabricated by electrospinning, resulting in fiber diameters between 850 and 1200 nm and pore sizes between 14 and 20 mu m. The anticoagulant efficiency of the membranes containing hawthorn extract reached 430 s in the Activated Partial Thromboplastin Time Assay (aPTT). Mechanical testing revealed a tensile strength of 22.70 +/- 6.33 MPa, an elongation of 53.58 +/- 10.63%, and Young's modulus of 0.67 +/- 0.10 MPa. The scaffold also exhibited over 91% cell viability and excellent cardiomyocyte adhesion. The hemolysis ratio was determined to be 0.421 +/- 0.191%, which confirms its blood compatibility. Our results indicate that the proposed bilayered scaffold can be a promising candidate for cardiac patch applications.The Scientific and Technological Research Council of Turkiye [122M020]This project is financially supported by TUBITAK with the project number 122M020
Role of Long Non-Coding RNA X-Inactive Transcript (XIST) in Neuroinflammation and Myelination: Insights From Cerebral Organoids and Implications for Multiple Sclerosis
No full textSen, Alaattin/0000-0002-8444-376X; Acar, Busra/0000-0002-4772-2698Background/Objectives: X-inactive-specific transcript (XIST) is a factor that plays a role in neuroinflammation. This study investigated the role of XIST in neuronal development, neuroinflammation, myelination, and therapeutic responses within cerebral organoids in the context of Multiple Sclerosis (MS) pathogenesis. Methods: Human cerebral organoids with oligodendrocytes were produced from XIST-silenced H9 cells, and the mature organoids were subsequently treated with either FTY720 or DMF. Gene expression related to inflammation and myelination was subsequently analyzed via qRT-PCR. Immunofluorescence staining was used to assess the expression of proteins related to inflammation, myelination, and neuronal differentiation. Alpha-synuclein protein levels were also checked via ELISA. Finally, transcriptome analysis was conducted on the organoid samples. Results: XIST-silenced organoids presented a 2-fold increase in the expression of neuronal stem cells, excitatory neurons, microglia, and mature oligodendrocyte markers. In addition, XIST silencing increased IL-10 mRNA expression by 2-fold and MBP and PLP1 expression by 2.3- and 0.6-fold, respectively. Although XIST silencing tripled IBA1 protein expression, it did not affect organoid MBP expression. FTY720, but not DMF, distinguished MBP and IBA1 expression in XIST-silenced organoids. Furthermore, XIST silencing reduced the concentration of alpha-synuclein from 300 to 100 pg/mL, confirming its anti-inflammatory role. Transcriptomic and gene enrichment analyses revealed that the differentially expressed genes are involved in neural development and immune processes, suggesting the role of XIST in neuroinflammation. The silencing of XIST modified the expression of genes associated with inflammation, myelination, and neuronal growth in cerebral organoids, indicating a potential involvement in the pathogenesis of MS. Conclusions: XIST may contribute to the MS pathogenesis as well as neuroinflammatory diseases such as and Alzheimer's and Parkinson's diseases and may be a promising therapeutic target.Scientific and Technological Research Council of Turkiye [TUBITAK 119Z389]; Health Institutes of Turkiye [TUSEB 28520]This work was supported by grants from the Scientific and Technological Research Council of Turkiye (TUBITAK 119Z389) and the Health Institutes of Turkiye (TUSEB 28520)
Achieving High Optical Absorption in Thin Film Photovoltaic Devices via Nanopillar Arrays and Metal Nanoparticles
No full textIn this study, crystalline silicon nanopillars has been employed as a hexagonal array photonic crystal structure with low optical reflection, augmented by silver metallic nanoparticles ranging from 10 to 50 nm in diameter in order to achieve high absorption in thin silicon films, a critical factor for applications in photovoltaic devices. Initially, it has been begun with an optimized structure in terms of pillar filling ratio, pillar height, and diameter, as established in the previous study. This allows to obtain a hexagonal array of nanopillars with a surface characterized by low optical reflection. To enhance the optical absorption within the bulk of the silicon thin film, the optical scattering properties of silver (Ag) metallic nanoparticles (MNPs) has been harnessed. The integration of silver metal nanoparticles into the photonic crystal hexagonal nanopillar array involved introducing a cavity into the silicon pillar. Placing Ag MNPs near the bottom of the cavity prevented the degradation of the photonic crystal's ability to maintain low reflection within the desired optical spectrum (between 400-1100 nm). Comparison between the nanopillar hexagonal array structure with Ag MNPs and the bare silicon substrate revealed a remarkable 104.76 percent increase in optical absorption for a 1-micron thick silicon bulk material. This triple hybrid structure exhibits tremendous potential in photovoltaic device applications, including solar cells and photodetectors, with the capacity to significantly enhance conversion efficiency.TUBITAK ARDEB 1001 [219M280]; TUBITAK ARDEB 1001 project; Abdullah Gul University (AGU)This study was supported by the TUBITAK ARDEB 1001 project (No. 219M280) and computing resources were provided by Abdullah Gul University (AGU). The author expresses gratitude to Prof. Dr. Mehmet Sahin, Prof. Dr. Mehmet Emre Tasgin, and Prof. Dr. Hakan Usta for their valuable contributions to the discussions on the subject
Tuning Mechanical Performance of PCL Scaffolds: Influence of 3D Bioprinting Parameters, Polymer Concentration, and Solvent Selection
No full textThe mechanical performance of three-dimensional (3D) bioprinted scaffolds is susceptible to printing parameters and material formulation. In this study, poly (epsilon-caprolactone) (PCL) scaffolds were fabricated using four different polymer concentrations (10%, 25%, 50%, and 75% w/v) to investigate how these variations, along with process parameters, influence mechanical behavior. Maintaining the structural integrity of bioprinted constructs requires careful optimization of polymer concentration and precise control over parameters such as printing speed, pressure, and infill density. Tensile tests were conducted to evaluate the effects of these variables. Among the tested conditions, a 50% (w/v) concentration allowed for a broader operational window, enabling fabrication across a range of printing speeds and pressures. At a printing speed of 5 mm s-1, PCL-DCM exhibited a Young's modulus of 39.0 MPa, while PCL-CF samples printed at 10 mm s-1 achieved the highest modulus of 32.0 MPa. Notably, when the printing speed was kept constant, applying higher pressures led to an increase in Young's modulus, suggesting that pressure plays a key role in enhancing scaffold stiffness. When comparing the 50% and 75% (w/v) polymer concentrations, the 50% (w/v) formulation stood out by offering both higher elongation and greater stiffness, which makes it particularly suitable for load-bearing applications. These findings provide a quantitative framework for optimizing extrusion-based bioprinting of PCL scaffolds, with implications for customized biomedical implants and regenerative medicine
Exploring Transdisciplinary Interaction in Higher Education: Urbanism Through Informal Learning Environment
No full textKesim, Berk/0000-0001-8772-4084PurposeThis study aims to explore interdisciplinary and transdisciplinary interactions around sustainability, focusing on the United Nations sustainable development goals (SDGs). By using the city as an informal learning space, it presents a case study to raise SDG awareness, promote interdisciplinarity, foster critical thinking and empower students.Design/methodology/approachUsing qualitative content analysis, this study explores students' interdisciplinary engagements. The research centers on student-created Logbooks, combining field data for analysis via open coding.FindingsThe informal setting facilitates transdisciplinary interaction and enriches interdisciplinary skills while retaining individuals' disciplinary tendencies.Research limitations/implicationsFactors like local geographical conditions and participant numbers could lead to minor variations in future course applications. Although initial problem topics and discussions are confined to local urban geography, they might diversify during implementation.Practical implicationsThe Logbook serves as a guide for local urban issues and embodies interdisciplinary outcomes. It can be enhanced with maps and problem zoning.Social implicationsDemonstrates effective SDG integration into higher education.Originality/valueThis study spotlights interdisciplinary learning within an unconventional context - urbanism - bridging student gaps. Supported by a paradigm shift from sustainability to unsustainability, it underscores the significance of critical engagement with SDGs
Ground Failures and Foundation Performances in Adıyaman-Gölbaşı Following the 6 February 2023 Kahramanmaraş-Türkiye Earthquake Sequence
No full textThe 6 February 2023 Kahramanmara & scedil;-T & uuml;rkiye earthquake sequence (M7.8 and M7.6) presents an exceptional opportunity to investigate both the effects of local soil conditions on damage patterns under strong shaking conditions and the performance of building foundations in areas that experienced ground failure. The significant ground failure and structural damage in Ad & imath;yaman-G & ouml;lba & scedil;& imath; triggered an intensive series of detailed reconnaissance and field surveys. This article aims to present the resulting database of observations on ground failures, building, and foundation performances. The field reconnaissance of ground failures and their effects on building performances involved aerial and walk-down surveys, including high-quality photographs taken across the town. In addition, data on building damage statistics compiled by the Ministry of Environment, Urbanization, and Climate Change were accessed and analyzed. The subsurface characteristics of the town were characterized using available data from pre-earthquake site investigation campaigns employed for town planning purposes. It is concluded that the ground failures in the town primarily resulted from soil liquefaction and cyclic softening. Most of the poor building and foundation performances and ground failures were documented in the northern part of Atat & uuml;rk Boulevard, closer to the lake of G & ouml;lba & scedil;& imath;, where soil site characteristics were unfavorable. This revealed once again the significant effects of local soil site conditions, particularly soil liquefaction, on the intensified ground failures, foundation, and structural damage levels.Scientific and Technological Research Institution of Turkiye (TUBITAK)The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partially supported by The Scientific and Technological Research Institution of Turkiye (TUBITAK) ''1002-C Natural Disasters-Focused Fieldwork Emergency Support Program (Dogal Afetler Odakl & imath; Saha Cxal & imath;sxmas & imath; Acil Destek Program & imath;).'