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Article Citation - WoS: 2Citation - Scopus: 3Intensive Parenting of Mothers in 11 Countries Differing in Individualism, Income Inequality, and Social Mobility(Pergamon-Elsevier Science Ltd, 2025) Lubiewska, Katarzyna; Zeglen, Marta; Lun, Vivian Miu-Chi; Park, Joonha; Runge, Ronja; Muller, Jacomien; van der Kaap-deeder, JoleneAlthough intensive parenting has been found to be mostly detrimental for both children and parents, less is known about the correlates and sources of this type of parenting. This study aimed to examine associations between mother's primary involvement in caregiving and intensive parenting, as well as their potential sources, thereby focusing on: family social status, characteristics of the national economy (income inequality and social mobility) and culture (individualism-collectivism) in 11 culturally diverse countries. Participants were 2535 mothers of children aged between 6 and 10. Mothers reported on their intensive parenting behaviors, entailing both supportive and undermining aspects of meeting their child's needs, as well as their level of involvement in daily caregiving tasks and the subjective family social status. Hypotheses were tested controlling for country level response style. Results revealed that: mothers who were more often the primary caregiver across daily tasks used more intensive parenting behaviors; high social status mothers were using less child need undermining yet more supportive intensive parenting behaviors, and less frequently served as the primary caregiver for daily tasks; the undermining intensive parenting behaviors related positively to country-level individualism and income inequality, whereas relations with social mobility were mixed.Article A Computationally Efficient Approximation for Fractional Differencing: First-Order Operators(Pergamon-Elsevier Science Ltd, 2026) Omay, Tolga; Baleanu, DumitruThis paper introduces the First-Order Fractional Differencing (FOFD) operator that substantially reduces the computational burden of fractional differencing for large-scale applications. While the standard Gr & uuml;nwald-Letnikov (GL) operator requires O(T2) operations for a series of length T, and recent FFT-based methods achieve O(T log T), our FOFD operator requires only O(T) operations through a simple two-point recursion. We develop an optimal weight calibration framework that ensures this computational efficiency does not compromise statistical accuracy, deriving a general formula wopt = d & sdot; (1-0.9 rho)beta(p) that adapts to the persistence structure of autoregressive processes. Empirical applications demonstrate substantial improvements: for the Chicago Fed National Financial Conditions Index with extreme persistence (rho= 0.992), optimal weight calibration reduces approximation error by 93% while preserving the autocorrelation structure of the GL operator. For a series of 10,000 observations, our method requires 20,000 operations compared to 530,000 for FFT-based methods and 50 million for standard implementations-enabling fractional differencing in real-time and high-frequency contexts previously infeasible due to computational constraints. The method's simplicity, requiring no specialized libraries and providing direct implementation through our calibration formula, makes it immediately accessible to practitioners while maintaining the long-memory properties essential for financial time series modeling.Article International Students' Adaptation in Ankara: The Mediating Roles of Anxiety and Self-Esteem(Pergamon-Elsevier Science Ltd, 2025) AlQaifi, FatenWith globalization, the appeal of studying abroad has grown among university students seeking better educational and career opportunities. However, adapting to a new culture often presents significant challenges, especially as international students face language barriers, cultural differences, and stressors that affect their anxiety, self-esteem, and identity development. Despite the importance of these factors, research on this topic in Turkey remains limited. This study addresses this gap by assessing general anxiety levels of students and examining the relationship between adaptation and identity development among international students, using cross-sectional quantitative methods and self-reported questionnaires. Data from 488 participants were analyzed using SPSS and SmartPLS. Results indicate that both anxiety and self-esteem partially mediate the relationship between identity development and adaptation. Anxiety negatively associates with both identity development and adaptation, while self-esteem shows positive associations with both. Proficiency level and previous travel experience were identified as significant factors influencing students' adaptation. These findings offer valuable insights for universities, policymakers, and other stakeholders in creating a supportive environment that enhances the adaptation experience of international students.Article Citation - WoS: 3Citation - Scopus: 4The Design and Techno-Economic Evaluation of Wind Energy Integrated On-Site Hydrogen Fueling Stations for Different Electrolyzer Technologies(Pergamon-Elsevier Science Ltd, 2025) Devrim, Yilser; Ozturk, Reyhan AtabayHydrogen refueling stations (HRS) integrated with renewable energy sources present a pivotal solution for achieving sustainable transportation systems. This study focuses on the design and techno-economic analysis of a grid-connected, on-site hydrogen production HRS powered by wind energy, incorporating various electrolyzer technologies. The selected location for the HRS installation is & Ccedil;anakkale, Turkey, where daily wind speed data has been utilized for performance calculations. The proposed HRS system integrates a wind turbine (WT) with three different electrolyzer technologies: alkaline electrolyzer (AEL), proton exchange membrane electrolyzer (PEMEL), and anion exchange membrane electrolyzer (AEMEL). A comprehensive techno-economic analysis was conducted to evaluate the system's performance, considering factors such as initial capital investment, installation, operation, and replacement costs. The results of the analysis reveal that the levelized cost of hydrogen (LCOH) varies between 9.0 and 18.7 /kg H2, depending on the type of electrolyzer technology used and the daily hydrogen refueling capacity. Notably, increasing the hydrogen refueling capacity significantly reduces production costs. The minimum LCOH of 9.0 /kg H2, achieved under a 20-year investment scenario, corresponds to a refueling capacity of 250 kg H2/day when utilizing the AEL-integrated HRS system. The findings underscore the economic feasibility of on-site hydrogen refueling stations powered by wind energy and utilizing AEL, AEMEL, and PEMEL systems. Among the systems analyzed, the AEL-based HRS system demonstrated the highest return on investment (ROI) of 13.02 % and the shortest payback period (PBP) of 7.7 years, highlighting its economic performance. This study provides valuable insights into the integration of renewable energy with hydrogen production infrastructure, emphasizing the potential of wind-powered HRS systems to advance the sustainability and economic viability of hydrogen-based transportation solutions.Article Citation - WoS: 3Citation - Scopus: 3A Review on Membranes for Anion Exchange Membrane Water Electrolyzers(Pergamon-Elsevier Science Ltd, 2026) Altinisik, Hasan; Celebi, Ceren; Ozden, Adnan; Devrim, Yilser; Colpan, C. OzgurAnion exchange membrane water electrolyzers (AEMWEs) - using water and renewable electricity as the input - provide a sustainable pathway to hydrogen production. AEMWEs perform the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) with modest overpotentials at practical current densities (>1 A cm(-2)). The recent catalysis, component, and system-level breakthroughs have enabled significant improvements in current densities and energetic efficiencies. The challenge, however, is to maintain these impressive activities and efficiencies through long-term operation at scale. High-performance, efficient, stable, and economically viable AEMWEs require high-performance, low-cost, and scalable anion exchange membranes (AEMs). This Review provides an overview of physical, chemical, and transport properties of commercial and non-commercial AEMs. The article discusses the operating principles, structures, characteristics, strengths, and weaknesses of conventional and emerging AEMs, along with their performance and stability implications in AEMWEs. The article highlights the characteristics that have intricate implications on performance, stability, and cost. It discusses recent advances and best practices to combine high-performance, efficiency, stability, and low-cost in a single AEM structure. The Review highlights the trade-offs between AEM characteristics, with an overview of emerging approaches that would overcome performance, stability, and cost challenges. The Review concludes by highlighting the research gaps and providing research directions with the potential to take the technology a step closer to wide-scale deployment.Article First-Principles Investigation of Kaolinite/YSZ Heterostructure for Solar-Driven Photocatalytic Hydrogen Production(Pergamon-Elsevier Science Ltd, 2025) Park, Jongee; Yu, Eunmi; Fatima, Syeda AfrinishThis work employs density functional theory (DFT) to elucidate the structural, electronic, and photocatalytic properties of a kaolinite/yttria-stabilized zirconia (Kaol/YSZ) heterostructure tailored for solar-driven hydrogen generation. The lattice mismatch between Kaol(001) and YSZ(111) was determined to be 4.4 % along the a-axis and 2.2 % along the b-axis. Two interface terminations were modeled: an O-terminated Si-O surface and an OH-terminated Al-OH surface. The OH-terminated interface demonstrated a stronger interfacial binding energy (-9.32 eV per cell) and enhanced thermodynamic stability, indicating its suitability for photocatalytic water splitting. Electronic structure analysis reveals that the Kaol/YSZ heterostructure exhibits a narrowed band gap of 1.46 eV relative to the isolated components, which promotes enhanced visible-light absorption. A type-II band alignment is observed, facilitating photoinduced electron transfer from the conduction band of YSZ to the conduction band of Kaol and promoting efficient charge separation. Hirshfeld charge analysis confirms the existence of a built-in electric field at the interface that further drives charge migration. Calculated optical absorption spectra shows a red shift in the heterostructure's absorption edge, extending its photoresponse into the visible region. Under simulated solar irradiation, photogenerated electrons preferentially migrate to Kaol for proton reduction, while holes remain on the YSZ surface to oxidize water, enabling simultaneous H2 evolution and O2 evolution pathways. These findings highlight the promise of the Kaol/YSZ heterostructure as a robust visible-light photocatalyst for sustainable hydrogen production and environmental remediation.Article Citation - WoS: 7Citation - Scopus: 7Reliability and Optimal Age-Based Replacement Policy for Consecutive 2-Out System Equipped With Protection Blocks(Pergamon-Elsevier Science Ltd, 2025) Eryilmaz, SerkanThis paper concerns the reliability evaluation and optimal age-based replacement policy for the linear consecutive 2-out-of-n:G system whose two consecutive components are protected by a block that has its own failure rate. Two alternative methods are proposed to compute the reliability of the system. The first method is based on direct probabilistic approach and uses the reliability of the ordinary consecutive 2-outof-n:G system. The second method is based on the concept of survival signature. Closed form equations for the system reliability and the mean number of failed components within the system are obtained. The optimal age-based replacement policy is also defined and studied. Extensive numerical results are presented to illustrate the findings.Article Potential Localization Strategies and Strategic Instruments in Nuclear Power Generation(Pergamon-Elsevier Science Ltd, 2026) Ege, AhmetDeploying the right strategies is of paramount importance and plays a key role in technology transfer to achieve localization. Today, around 30 countries are considering or embarking on nuclear power programs. What are the potential strategies for nuclear power technology localization? This study attempts to identify localization strategies in nuclear technology and also to unfold tested approaches, business models, strategic legal and technical instruments. The methodology of the study treats the nuclear industry in a state as a "unit" in which a variation of PEST analysis is implemented to reveal macro-environmental factors followed by SWOT analysis to identify strengths, weaknesses, opportunities and threats of available approaches, business models, legal and technical instruments. Four principal strategies emerge: (1) learning by doing; (2) transfer, adopt, assimilate, develop and export; (3) own or operate with limited transfer; and (4) wait and see. The first two strategies are proposed for the countries willing to launch an ambitious nuclear power program. Own or operate with limited transfer strategy can be deployed in those countries prioritizing security of supply, source of reliable base load generation, general economic development, technological and qualified human resources development. Wait and see strategy is convenient for those countries awaiting progress of new technologies or phased out nuclear power but planning to reintroduce it in the future. Regardless of the strategy selected, wise guiding policies and coherent set of actions must be deployed for a successful assimilation and acquisition of the design,Article Prevalence of Toxoplasma Gondii in Patients with Schizophrenia and Its Association with Clinical Symptoms(Pergamon-Elsevier Science Ltd, 2025) Kurkcu, Muhammed Furkan; Korkut, Gizem; Varli, Mehmet Ridvan; Yilmaz, Gulsum; Usluca, Selma; Bakir, AyferBackground: Schizophrenia is a multifactorial neuropsychiatric disorder influenced by both genetic predisposition and environmental factors. Recent evidence suggests a possible link between latent Toxoplasma gondii infection and schizophrenia, though the underlying mechanisms remain unclear. Objective: To compare the seroprevalence of T. gondii in patients with schizophrenia and healthy individuals, and to evaluate the relationship between seropositivity and clinical parameters. Methods: A total of 265 participants (155 schizophrenia patients and 110 healthy controls) were enrolled. IgG and IgM antibodies were detected using electrochemiluminescence immunoassay (ECLIA), avidity was assessed using ELISA, and DNA presence was tested with real-time PCR. Clinical symptoms were evaluated using the Brief Psychiatric Rating Scale (BPRS). Statistical analysis included logistic regression and non-parametric tests (p < 0.05). Results: T. gondii IgG seropositivity was significantly higher in schizophrenia patients (29 %) than in controls (18.2 %) (p = 0.044, OR = 1.84; 95 % CI: 1.01-3.34). IgM positivity and DNA detection did not differ significantly. All seropositive participants showed high IgG avidity, indicating latent infection. BPRS scores and illness duration were higher in IgG-positive individuals, but the differences were not significant. Conclusion: Latent T. gondii infection may be associated with schizophrenia. However, further multicenter studies integrating molecular and serological approaches are needed to clarify its role in disease pathogenesis.
