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Article Does Dexmedetomidine Induce Bone Regeneration in Cranial Defects in Rabbits(Taylor & Francis Ltd, 2025) Erkan, Gozde Nur; Tekin, Umut; Boyacioglu, Ozge; Korkusuz, Petek; Orhan, Kaan; Kirman, Betul; Onder, Mustafa ErcumentDexmedetomidine has been shown to exert protective and curative effects on various tissues and organs in different pathological processes. This study aimed to investigate the effect of dexmedetomidine on the regeneration process after making holes in the parietal bones of rabbits. Twenty-four male Oryctolagus cuniculus rabbits were allocated to three groups, and an 8-mm circular parietal critical-sized bone defect was induced in each animal. Group_C (control) received saline; Group_LD (low dose) was given dexmedetomidine 2.75 mu g/kg; Group_HD (high dose), dexmedetomidine 5.5 mu g/kg; all were administered intraperitoneally for 7 days. After 8 weeks the bones were examined by micro-computed tomography (micro-CT) and histomorphometry. The results indicated that regeneration was improved in both the dexmedetomidine-treated groups. The lower dose increased the bone volume ratio (BV/TV) more than the higher dose. Trabecular thickness, connectivity value, and connectivity density were also higher in Group_LD than in Group_HD. Significant intramembranous ossification was observed in the dexmedetomidine-treated groups, and active osteoblasts were seen at the margins of new bone trabeculae. We conclude that dexmedetomidine, especially at the lower dosage, increases osteoblastic activity and regeneration quality.Article Dirichlet-Type Problems for n-poisson Equation in Clifford Analysis(Taylor & Francis Ltd, 2022) Aksoy, Umit; Celebi, A. OkayIterated Dirichlet problem, also called as Riquier or Navier problem, and polyharmonic Dirichlet problem are studied for n-Poisson equation in Clifford analysis using iterated polyharmonic Green function and polyharmonic Green-Almansi type function appropriate for the boundary conditions of the problems.Article Citation - WoS: 2Citation - Scopus: 3Physical and Biological Characteristics of Electrospun Poly (vinyl Alcohol) and Reduced Graphene Oxide Nanofibrous Structure(Taylor & Francis Ltd, 2024) Sasmazel, Hilal Turkoglu; Alazzawi, Marwa; Gozutok, Melike; Sadhu, VeeraThe fabrication of graphene-based nanocomposites has been a topic of increasing interest due to graphene's exceptional physical properties and the ability to enhance the properties of various polymeric materials. Evaluating the biocompatibility of these nanocomposites is crucial to ensure their safe and effective use in biomedical applications. This study characterized and assessed the biocompatibility of previously fabricated electrospun polyvinyl alcohol (PVA)/reduced graphene oxide rGO fibrous structures by conducting a comprehensive assessment of their physical and biological characteristics. Contact angle measurements revealed that adding rGO to electrospun PVA fibers enhanced the surface wettability, improving the fibrous structure's PBS absorption capacity and degradation behavior. Including the rGO content resulted in a higher water vapor transmission rate, reaching similar to 48 g/m2day for PVA + 0.5 wt.% rGO and similar to 45 g/m2day for PVA + 1.0 wt.% rGO, compared to similar to 40 g/m2day for electrospun PVA fibers. Cell culture studies, including MTT assay, alkaline phosphatase (ALP) activity analysis, alizarin red staining, fluorescence microscopy, and SEM analyses, demonstrated that electrospun PVA + 1.0 wt.% rGO nanocomposites exhibited superior cell viability, proliferation, and growth compared to other samples, due to the improved physical properties of the PVA + 1.0 wt.% rGO fibrous structure.Article Citation - WoS: 2Citation - Scopus: 2Finite Element Analysis of Stress Distribution on Modified Retentive Tips of Bar Clasp(Taylor & Francis Ltd, 2012) Oyar, P.; Soyarslan, C.; Can, G.; Demirci, E.This study used finite element analysis to evaluate the retentive tips of bar clasps made from different alloys and using different designs in order to determine whether or not different materials and tip forms are suitable for bar clasp applications. Co-Cr, Ti and Type IV Au alloys were selected based on their physical and mechanical properties. The 3D finite element models of three different bar clasp retentive tip geometries prepared from Co-Cr, Ti and Type IV Au alloys were constructed using the finite element software package MSC. Marc. Analysis of a concentrated load of 5N applied to the removable partial denture approach arms in an occlusal direction was performed. Although stress distribution and localisation within bar clasps with different retentive tips were observed to be similar and were concentrated in the approach arm, stress intensities differed in all models.Article Citation - WoS: 2Citation - Scopus: 2Space-charge-limited currents and photoconductive properties of Tl2InGaSe4 layered crystals(Taylor & Francis Ltd, 2008) Qasrawi, A. F.; Gasanly, N. M.The extrinsic electronic parameters of Tl2InGaSe4 layered crystals were investigated through measurement of the temperature-dependent dark conductivity, space-charge-limited currents and photoconductivity. Analysis of the dark conductivity reveals the existence of two extrinsic energy levels at 0.40 and 0.51 eV below the conduction band edge, which are dominant above and below 260 K, respectively. Current-voltage characteristics show that the one at 0.51 eV is a trapping energy level with a concentration of (4.8-7.7) x 10(10) cm(3). Photoconductivity measurements reveal the existence of another energy level located at 0.16 eV. In the studied temperature range, the photocurrent increases with increasing temperature. The dependence of the photoconductivity on the incident light intensity exhibits a linear recombination character near room temperature and a supralinear character as the temperature decreases. The change in recombination mechanism is attributed to an exchange in the behavior of sensitizing and recombination centres.Article Citation - WoS: 10Citation - Scopus: 10Higher Rates of Cefiderocol Resistance Among Ndm Producing klebsiella Bloodstream Isolates Applying Eucast Over Clsi Breakpoints(Taylor & Francis Ltd, 2023) Isler, Burcu; Vatansever, Cansel; Ozer, Berna; Cinar, Gule; Aslan, Abdullah Tarik; Falconer, Caitlin; Harris, Patrick N. A.BackgroundCefiderocol is generally active against carbapenem-resistant Klebsiella spp. (CRK) with higher MICs against metallo-beta-lactamase producers. There is a variation in cefiderocol interpretive criteria determined by EUCAST and CLSI. Our objective was to test CRK isolates against cefiderocol and compare cefiderocol susceptibilities using EUCAST and CLSI interpretive criteria.MethodsA unique collection (n = 254) of mainly OXA-48-like- or NDM-producing CRK bloodstream isolates were tested against cefiderocol with disc diffusion (Mast Diagnostics, UK). Beta-lactam resistance genes and multilocus sequence types were identified using bioinformatics analyses on complete bacterial genomes.ResultsMedian cefiderocol inhibition zone diameter was 24 mm (interquartile range [IQR] 24-26 mm) for all isolates and 18 mm (IQR 15-21 mm) for NDM producers. We observed significant variability between cefiderocol susceptibilities using EUCAST and CLSI breakpoints, such that 26% and 2% of all isolates, and 81% and 12% of the NDM producers were resistant to cefiderocol using EUCAST and CLSI interpretive criteria, respectively.ConclusionsCefiderocol resistance rates among NDM producers are high using EUCAST criteria. Breakpoint variability may have significant implications on patient outcomes. Until more clinical outcome data are available, we suggest using EUCAST interpretive criteria for cefiderocol susceptibility testing.Article Citation - WoS: 2Citation - Scopus: 2An Investigation of Recycled Rubber Composites Reinforced With Micro Glass Bubbles: an Experimental and Numerical Approach(Taylor & Francis Ltd, 2024) Kabakci, Gamze Cakir; Bayraktar, Emin; Aslan, OzgurRecycled rubber is widely used for its lightweight and cost-effective properties but often has limited mechanical strength, restricting its applications. This study enhances the mechanical performance of devulcanised recycled rubber by reinforcing it with micro glass bubbles (GBs) featuring a density of 0.65 g/cm(3) and an elastic modulus of 3.5 GPa, offering a high strength-to-density ratio. Uniaxial compression tests were conducted on samples with GB volume fractions of 5%, 10%, and 15%. Results were validated through finite element analysis (FEA) in ABAQUS/Standard, incorporating randomised GB distributions. A 2D representative volume element (RVE) with randomly distributed GBs was modelled, applying periodic boundary conditions to simplify the composite into an equivalent homogeneous material. Numerical simulations assessed the effects of GB diameters (30, 40, and 50 mu m) and inclusion size ranges (20-50 mu m and 10-60 mu m), finding minimal impact on results. The RVE, sized at 238 mu m, accurately represented macroscale composite behaviour. Stress-strain behaviour was analysed using average stress and strain tensors. The strong agreement between experimental and numerical results validates the proposed method, demonstrating its accuracy in predicting the mechanical behaviour of the reinforced composite material.Article Citation - WoS: 11Citation - Scopus: 12Structural, optical, electrical and dielectric properties of Bi1.5Zn0.92Nb1.5-xNixO6.92-3x/2 solid solution(Taylor & Francis Ltd, 2012) Qasrawi, A. F.; Nazzal, E. M.; Mergen, A.The effects of Ni content on the structural, optical, dielectric and electrical properties of Bi1.5Zn0.92Nb1.5O6.92 pyrochlore ceramics have been investigated. Nickel atoms were inserted into pure samples in accordance to the composition Bi1.5Zn0.92Nb1.5-xNixO6.92-3x/2, with x varying from 0.07 to 0.40. The structural analysis revealed that a single phase of the pyrochlore compound can be obtained for x values of 0.07 and 0.10 only. Further increase in Ni caused the appearance of multiple phases. The optical energy band gaps are determined as 3.30, 3.35 and 3.52 eV for Ni content of 0.00, 0.07 and 0.10 respectively. The temperature dependent electrical resistivity and the frequency dependent capacitance are observed to increase with increasing Ni content. The resonance frequency, which was determined from the capacitance-frequency dependence, was observed to shift from 12.14 to 10.47 kHz as the x values increase from 0.00 to 0.10 respectively.Article Citation - WoS: 16Citation - Scopus: 17Organizational Software Piracy: an Empirical Assessment(Taylor & Francis Ltd, 2007) Mishra, Alok; Akman, Ibrahim; Yazici, AliApplication of Information Technology (IT) has had a significant impact on all aspects of business. Due to technology, the ease with which software can be pirated is increasing and is leading to increased concern for copyright protection. This paper reviews and discusses software piracy issues from a global perspective and reports the findings of a survey concerning the impact of sectors like government, private and academic in Turkey. Although software piracy has long been attracting the interest of academics, no quantitative research has ever been realized in this field in the country. Elsewhere also, most of the software piracy-related studies are from individuals' perspectives and are limited to students, academics, cost, and attitudes. Very few have reported findings related to IT professionals and organizations. The survey was conducted among IT managers of large-scale organizations from different sectors such as the government, private and academic community. Based on the survey of 162 IT managers, the results indicated that sectors have significant impact on software piracy to some extent.Article Citation - WoS: 2Citation - Scopus: 2Estimation in the Partially Nonlinear Model by Continuous Optimization(Taylor & Francis Ltd, 2021) Yerlikaya-Ozkurt, Fatma; Taylan, Pakize; Tez, MujganA useful model for data analysis is the partially nonlinear model where response variable is represented as the sum of a nonparametric and a parametric component. In this study, we propose a new procedure for estimating the parameters in the partially nonlinear models. Therefore, we consider penalized profile nonlinear least square problem where nonparametric components are expressed as a B-spline basis function, and then estimation problem is expressed in terms of conic quadratic programming which is a continuous optimization problem and solved interior point method. An application study is conducted to evaluate the performance of the proposed method by considering some well-known performance measures. The results are compared against parametric nonlinear model.
