WoS
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14411/18
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Article Weyl Double Copy in Lifshitz Spacetimes(Amer Physical Soc, 2026) Gumu, Mehmet Kemal; Alkac, Gokhan; Olpak, Mehmet AliLifshitz black hole solutions pose particular challenges for reconciling the two main formulations of the classical double copy: the Kerr-Schild double copy and the Weyl double copy. Recent work has suggested that consistency between the two can be restored, in certain cases, only by adopting a regularization prescription in the Weyl double copy. In this paper, we test this prescription on three examples from the literature, each with a distinct novel feature, and show that the prescription remains valid in all cases.Article Time-Varying Sectoral Exchange Rate Pass-through and Its Structural Drivers: The Case of Turkish Manufacturing Industries(Springer, 2026) Saygılı, HülyaThis study examines how exchange rate pass-through (ERPT) varies across manufacturing sectors and which structural factors account for this heterogeneity over time. As a first step, the study constructs sector-level nominal effective exchange rate indices, generating a unique dataset that allows exchange rate movements to be matched directly to sector-specific trade structures. Using these indices, ERPT is estimated for Turkish manufacturing industries within a heterogeneous panel data framework. To enable systemic cross-sector comparison, a relative pass-through measure is developed that benchmarks each sector's ERPT against the manufacturing sector average. The analysis further explores the role of key structural characteristics-including trade openness, productivity, and global value chain participation-in shaping sectoral ERPT dynamics. The empirical results reveal significant disparities in pass-through across sectors, with persistent differences in sensitivity of exchange rate fluctuations. Structural determinants exhibit asymmetric effects: higher trade openness and deeper productivity tends to dampen ERPT. These findings highlights the importance of sector-specific characteristics for inflation dynamics and offer valuable policy insights for monetary and trade policy design.Article Thermal and Optical Signatures of Einstein-Dyonic ModMax Black Holes with GUP and Plasma Modifications(Elsevier, 2026) Sakallı, İzzet; Sucu, Erdem; Dengiz, SuatWe explore the thermodynamic and optical properties of Einstein-Dyonic-ModMax (EDM) black holes (BHs) incorporating quantum gravity corrections and plasma effects. The ModMax theory promotes the classical Maxwell theory to a non-linear electrodynamics with a larger symmetry structure (electromagnetic duality plus conformal invariance), and provides dyonic BH solutions characterized by both electric and magnetic charges modulated by the nonlinearity parameter gamma. Using the Hamilton-Jacobi tunneling formalism, we derive the Hawking radiation spectrum and demonstrate how the Generalized Uncertainty Principle (GUP) modifies the thermal emission, potentially leading to stable remnants. Our analysis of gravitational lensing employs the Gauss-Bonnet theorem to compute light deflection angles in both vacuum and plasma environments, revealing strong dependencies on the ModMax parameter and plasma density. We extend this to axion-plasmon environments, uncovering frequency-dependent modifications that could serve as dark matter signatures. The photon motion analysis in plasma media shows how the exponential damping term e-gamma affects electromagnetic backreaction on spacetime geometry. We compute quantum-corrected thermodynamic quantities, including internal energy, Helmholtz free energy, pressure, and heat capacity, using exponentially modified entropy models. The heat capacity exhibits second-order phase transitions with critical points shifting as functions of gamma, indicating rich thermodynamic phase structures. The energy condition analysis shows that classical ModMax electrodynamics satisfies the null and weak energy conditions, while the observed near-horizon violations arise only after incorporating quantum-corrected entropy effects.Article The Role of Motivational Interviewing in Enhancing Birth Self-Efficacy and Birth Satisfaction: A Randomized Controlled Study(Springer Publishing Co, 2026) Ozkan, Birgul; Sari, TugbaChildbirth is a critical and transformative experience in a woman's life; however, it is often accompanied by fear and perceived as a highly stressful event. Fear of childbirth may adversely affect a woman's confidence in her ability to give birth and her perceived competence regarding the birthing process. This study aimed to investigate the effect of motivational interviewing on childbirth self-efficacy and birth satisfaction among pregnant women. The study sample consisted of 85 pregnant women who were randomly assigned to either an intervention or a control group. Participants in the intervention group attended motivational interviewing sessions conducted over a 4-week period. Mode of birth and birth satisfaction were evaluated during the postpartum period. Among women in the intervention group, nearly 70% had a vaginal birth, and approximately 63% reported being satisfied with their childbirth experience. A statistically significant difference was observed between the groups in total childbirth self-efficacy scores following the intervention. The findings indicate that motivational interviewing can enhance childbirth self-efficacy and decrease the preference for cesarean birth.Trial registration: Registered in the ClinicalTrials.gov (NCT06082895).Article The Influence of Postural Load and Early Aging on Dynamic Sound Localization: Evidence for Reduced Cognitive-Motor Reserve(Springer, 2026) Batuk, Isa Tuncay; Batuk, Merve Ozbal; Karakuluk, IremThis study investigated the effects of head movements and postural stability on sound localization performance in normal-hearing adults and explored age-related differences between individuals aged 20-30 and 30-40 years. A total of 102 participants were divided into two groups: Group 1 (n = 56, 20-30 years) and Group 2 (n = 46, 30-40 years). Using a virtual reality system, localization performance was assessed under three different postural conditions and two listening conditions (head-immobile and head-mobile). Localization errors were measured at a 55-cm distance across four azimuth angles (right-front, left-front, right-back, left-back). Primary outcome measures included Azimuth Error, Front-Back Confusions, and Overall 3D Error. Incorporating head movements resulted in a statistically significant improvement in localization performance across all surface conditions (p < .001). In the head-mobile condition, the sitting posture yielded significantly lower Front 3D Error compared to both firm (p = .005) and foam surfaces (p = .007). Age-related differences were found to influence localization performance across varying levels of postural stability. Group 2 demonstrated significantly higher localization errors than Group 1 in the sitting condition (e.g., Head-Immobile Overall 3D Error: p = .021) and on the foam surface (e.g., Head-Immobile Overall 3D Error: p = .046). Conversely, no significant differences were found between the groups for any parameter on the firm surface. These findings indicate that head movements substantially enhance spatial hearing accuracy. However, localization performance is modulated by postural stability and age. Increased postural challenge appears to impose a dual-task cost, revealing subtle early age-related changes in the cognitive-motor mechanisms underlying auditory-spatial integration.Article The Effect of Lactoferrin on Cytosolic Antioxidant Enzymes, Glucose Uptake, and Wound Healing in Caco-2 Cells(Bayrakol Medical Publisher, 2025) Isgor, Yasemin Gulgun; Bodur, Mahmut; Ozcelik, Ayse Ozfer; Ayan, Firat; Isgor, Sultan BelginAim: The aim of this study is to investigate the dose-dependent effects of lactoferrin (LF) on glucose uptake, wound healing, and antioxidant enzyme activities in human colon carcinoma cells (Caco-2). Materials and Methods: Caco-2 cells were treated with LF (0-250 mu g/mL, 1:2 dilution), and its effects on cell viability using the MTT assay, glucose uptake using the 2-NBDG assay, wound healing using the scratch assay, and antioxidant enzyme activities by measuring superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) activities were evaluated. Results: Lactoferrin showed a dose-dependent cytotoxic effect, with IC50 values of 249.7 mu g/mL (24h) and 74.91 mu g/mL (48h). Glucose uptake was inhibited by 14% and 8% at 62.5 mu g/mL and 125 mu g/mL LF, respectively (p < 0.001). Lactoferrin significantly accelerated wound healing, achieving 90% closure at 72 hours, with 62.5 mu g/mL being the most effective dose. Antioxidant enzyme activity increased significantly, with SOD (155%), GPx (85%), and GST (53%) reaching peak levels at 125 mu g/mL LF (p < 0.001). Discussion: In conclusion, LF reduced glucose uptake, increased antioxidant enzyme activity, and accelerated wound healing in Caco-2 cells. These findings suggest that lactoferrin may have potential therapeutic applications in conditions related to oxidative stress, impaired glucose metabolism, and delayed wound healing, such as diabetes and chronic wounds. Further in vivo and human studies are needed to explore its clinical relevanceArticle Stochastic Comparisons of Mixtures of Heterogeneous Geometric Distributions Associated with Shock Models(Springer Heidelberg, 2026) Amini-Seresht, Ebrahim; Lorvand, Hamed; Balakrishnan, NarayanaswamyIn this paper, we discuss stochastic comparisons of two finite mixture models of different heterogeneous geometric distributions with different mixing proportions, in terms of usual stochastic, hazard rate, likelihood ratio and mean residual life orders. Finally, an application to shock models is discussed to illustrate the significance of the results established here.Article Reliability Evaluation of a System Protected by Blocks(Oxford Univ Press, 2026) Eryilmaz, SerkanWe model the reliability of a system with a main component and two auxiliary components for protection, one active, the other on cold standby. The main component performs the system function. The auxiliary components are called protection blocks. The failure rate of the main component depends on whether it is protected or not. The blocks have their own constant failure rate, that is, their lifetimes are exponentially distributed. The reliability of such a system is obtained and the properties of its failure rate are investigated. A necessary condition is obtained to compare the cost-effectiveness of single and two-block protection. Likewise, we obtain necessary conditions for comparing the effectiveness of different three-component designs under the mean time to failure criterion. In this way, the work provides decision support for the designers of systems protected by blocks.Article Profits, Wages, and Taxes: Understanding Inflation Dynamics in Türkiye(Sosyoekonomi Soc, 2026) Sakarya, Burçhan; Bülbül, Duran; Duvan, Osman BerkeThe COVID-19 pandemic and the Russia-Ukraine conflict have led to a global living standards shock, increasing interest in the interactions between firm profits and inflation. This study examines profit-driven inflation dynamics in Türkiye, also considering wages and net taxes. Using the deflator decomposition method and the Local Projections model, it analyses their effects on consumer inflation. Findings show that unit profit inflation is a key driver of price increases, while wage-price pass-through is nonlinear, and tax effects are delayed but significant. The study highlights the need for an integrated policy approach that combines monetary, fiscal, and competition policies to manage inflation effectively.Article Optimizing Drone-Based Humanitarian Relief in Post-Disaster Scenarios: A Hybrid MCDM and Maximum Coverage Approach(Springer Heidelberg, 2026) Vural, DanismentThis study proposes a novel hybrid decision-making framework that integrates expert-driven supply prioritization via the Stepwise Weight Assessment Ratio Analysis (SWARA) method with an operationally constrained Maximum Coverage Problem (MCP) model to optimize drone-based humanitarian logistics in post-disaster scenarios. Grounded in a real-world case study of the 2023 Kahramanmaraş earthquake, the model systematically elicits expert preferences to rank critical supplies such as food, medical items, and cold chain products, and embeds these weights directly into a constrained MCP formulation. The model incorporates drone-specific operational limits, including battery consumption, payload capacity, and round-trip feasibility, to ensure realistic deployment strategies. Results show that scenario configurations with four to five strategically located drone bases, each equipped with four to five drones, can increase the achieved priority-weighted delivered quantity by up to 35-40% compared to minimal base-drone configurations within the proposed model framework. Moreover, the proposed framework improves responsiveness by prioritizing urgent deliveries and supporting more timely allocation decisions under operational constraints. Unlike traditional MCP approaches that rely on static weights, this method offers a context-sensitive and scalable optimization model informed by field expertise. The findings underscore the potential of structured expert-based weighting combined with operational optimization to enhance the efficiency and responsiveness of drone-assisted disaster relief systems.