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Yayın Tulczyjew's triplet with an Ehresmann connection I: Trivialization and reduction(World Scientific, 2023-03-30) Esen, Oğul; Kudeyt, Mahmut; Sütlü, SerkanWe study the trivialization and the reduction of Tulczyjew's triplet, in the presence of a symmetry and an Ehresmann connection associated to it. We thus establish a geometric pathway for the Legendre transformations on singular dynamical systems.Yayın Hamiltonian dynamics on matched pairs(World Scientific Publishing Co, 2016-11-01) Esen, Oğul; Sütlü, SerkanThe cotangent bundle of a matched pair Lie group, and its trivialization, are shown to be a matched pair Lie group. The explicit matched pair decomposition on the trivialized bundle is presented. On the trivialized space, the canonical symplectic two-form and the canonical Poisson bracket are explicitly written. Various symplectic and Poisson reductions are perfomed. The Lie–Poisson bracket is derived. As an example, Lie–Poisson equations on (Formula presented.) are obtained.Yayın Testing a hypothesis for the evolution of sex(World Scientific Publishing Company, 2000-07-11) Örçal, Bora; Tüzel, Erkan; Sevim, Volkan; Jan, Naeem; Erzan, AyşeAn asexual set of primitive bacteria is simulated with a lit-string Penna model with a Fermi function for survival. A recent hypothesis by Jan, Stauffer, and Moseley on the evolution of sex from asexual cells as a strategy for trying to escape the effects of deleterious mutations is checked. This strategy is found to provide a successful scenario for the evolution of a stable macroscopic sexual population.Yayın Discrete dynamical systems over double cross-product Lie groupoids(World Scientific, 2021-03) Esen, Oğul; Sütlü, SerkanDiscrete Euler-Lagrange equations are studied over double cross product Lie groupoids. As such, a geometric framework for the local analysis of a discrete dynamical system is established. The arguments are elucidated on the local discrete dynamics of a gauge groupoid. The discrete Elroy's beanie is studied as a physical example.Yayın Shrinkage of olfactory amygdala connotes cognitive impairment in patients with Parkinson’s disease(Springer, 2023-10) Ay, Ulaş; Yıldırım, Zerrin; Erdoğdu, Emel; Kıçik, Ani; Öztürk Işık, Esin; Demiralp, Tamer; Gürvit, HakanDuring the caudo-rostral progression of Lewy pathology, the amygdala is involved relatively early in Parkinson’s disease (PD). However, lesser is known about the volumetric differences at the amygdala subdivisions, although the evidence mainly implicates the olfactory amygdala. We aimed to investigate the volumetric differences between the amygdala’s nuclear and sectoral subdivisions in the PD cognitive impairment continuum compared to healthy controls (HC). The volumes of nine nuclei of the amygdala were estimated with FreeSurfer (nuclear parcellation-NP) from T1-weighted images of PD patients with normal cognition (PD-CN), PD with mild cognitive impairment (PD-MCI), PD with dementia (PD-D), and HC. The appropriate nuclei were then merged to obtain three sectors of the amygdala (sectoral parcellation-SP). The nuclear and sectoral volumes were compared among the four groups and between the hyposmic and normosmic PD patients. There was a significant difference in the total amygdala volume among the four groups. In terms of nuclei, the bilateral cortico-amygdaloid transition area (CAT) and sectors superficial cortex-like region (sCLR) volumes of PD-MCI and PD-D were less than those of the PD-CN and HC. A linear discriminant analysis revealed that left CAT and left sCLR volumes classified the PD-CN and cognitively impaired PD (PD-CI: PD-MCI plus PD-D) with 90.7% accuracy according to NP and 85.2% accuracy to SP. Similarly, left CAT and sCLR volumes correctly identified the hyposmic and normosmic PD with 64.8% and 61.1% accuracies. Notably, the left olfactory amygdala volume successfully discriminated cognitive impairment in PD and could be used as neuroimaging-based support for PD-CI diagnosis.Yayın Thermoluminescence and optically stimulated luminescence properties of natural barytes(Elsevier Ltd, 2010-12) Kitis, George; Güneç Kıyak, Nafiye; Polymeris, George S.Heavy, baryte-loaded, concrete is commonly used as radiation shielding material around high energy particle accelerators. Concrete samples received from a shielding block located at CERN cite contain many crystalline inclusions which were identified as barytes by X-ray diffraction analysis and separated by their color, classified as white, orange and green. Basic properties of thermoluminescence (TL) and optically stimulated luminescence (OSL) signals of these barytes samples such as thermal and optical stability, repeatability and mainly the linearity of both their luminescence responses were investigated as a function of beta dose These results are also discussed regarding detailed investigation on the correlation between TL and OSL signals and their implications for retrospective dosimetryYayın Psychometric properties of the Turkish version of the eating pathology symptoms inventory (EPSI-T)(Cogent OA, 2025) Türk, Fidan; Acet, Pınar; Karabulut, Goncagül; Akay, NazlıThe purpose of this study was to examine the factor structure and psychometric properties of the Turkish version of the Eating Pathology Symptoms Inventory (EPSI‑T), and to explore gender differences in eating disorder symptoms. Participants were 473 university students in Türkiye (342 women, 113 men) who completed the EPSI‑T, along with the Modified Weight Bias Internalization Scale (WBIS‑M), Addiction‑like Eating Behaviour Scale (AEBS), Muscularity‑Oriented Eating Test (MOET), and Depression Anxiety and Stress Scales (DASS‑21). Confirmatory factor analysis supported the original eight‑factor, 45‑item structure [χ2(914) = 1994.57, χ2/df = 2.18, CFI = 0.90, RMSEA = 0.05 (0.05–0.06), SRMR = 0.07]. Women scored significantly higher on most subscales, except for Excessive Exercise, Muscle Building, and Negative Attitudes toward Obesity, where men scored higher (p < 0.005). Reliability was strong, with Cronbach’s α ranging from 0.72 to 0.90 and McDonald’s ω from 0.75 to 0.90. Convergent and discriminant validity were also supported. Overall, findings suggest that the EPSI‑T is a reliable and valid measure of eating disorder symptoms in Turkish‑speaking populations and may facilitate cross‑cultural research by providing a tool structurally consistent with the original English version.
