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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: 3Citation - Scopus: 3Modeling and Measurement of Human Body Blockage Loss at 28 Ghz(Taylor & Francis Ltd, 2023) Benzaghta, Mohamed; Gokdogan, Bengisu Yalcinkaya; Coruk, Remziye Busra; Kara, AliMillimeter-wave (mm-Wave) spectrum is an essential enabler to the fifth generation (5G) wireless technology. Humans are one of the most noticeable blockers that cause temporal variation in indoor radio channels. This paper presents human blockage measurements at 28 GHz, with several humans of different sizes. The effect of the crossing orientations of the human bodies is investigated for three different transmitter heights. A human blockage model based on the Fresnel diffraction scheme is shown to be applicable in estimating the human blockage loss in indoor radio links considering various body sizes, different crossing orientations, and different transmitter heights. The findings reported in this paper could help improve indoor radio channel models at 28 GHz bands for 5G technologies considering the presence of human body blockages.Article On the Injectivity With Respect To q of the Lupas q-transform(Taylor & Francis Ltd, 2024) Yilmaz, Ovgue Gurel; Ostrovska, Sofiya; Turan, MehmetThe Lupas q-transform has first appeared in the study of the Lupas q-analogue of the Bernstein operator. Given 0 < q < 1 and f is an element of C[0, 1], the Lupas q-transform is defined by Lambda(q)(f; x) Pi(infinity)(k=0) 1/1 + q(k)x Sigma(k=0)f(1 - q(k))q(k(k-1)/2)x(k)/(1 - q)(1 - q(2)) center dot center dot center dot (1 - q(k)), x >= 0. During the last decades, this transform has been investigated from a variety of angles, including its analytical, geometric features, and properties of its block functions along with their sums. As opposed to the available studies dealing with a fixed value of q, the present work is focused on the injectivity of Lambda(q) with respect to parameter q. More precisely, the conditions on f such that equality Lambda(q)(f; x) = Lambda(r)(f; x); x >= 0 implies q = r have been established.Article Citation - WoS: 6Citation - Scopus: 6On Reliability of Consecutive k-out-of-n:G System Equipped With Protection Blocks(Taylor & Francis Ltd, 2026) Eryilmaz, SerkanThe linear consecutive k-out-of-n:G system consists of n linearly ordered components such that the system works properly when there exists at least k consecutively working components. This paper is concerned with the reliability evaluation of the linear consecutive k-out-of-n: G system equipped with protection blocks. Protection blocks which have their failure rates are used to increase the system reliability. The closed-form expressions for the system reliability when $ 2k\geq n $ 2k >= n are obtained when the most critical components, i.e. the components that have the highest importance levels are involved by the protection blocks. Numerical examples are provided to illustrate the closed-form reliability equations.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 The Relationship Between Concentric and Isometric Strength of Knee Flexor and Extensor Muscles and Postural Stability in Mild Stage Multiple Sclerosis Patients(Taylor & Francis Ltd, 2025) Yilmaz, Seval; Unluer, Nezehat OzgulBackground Multiple sclerosis (MS) affects muscle strength and postural stability. However, the relationship between concentric and isometric strength of knee flexors and extensors and postural stability in mild stage MS is not well known. The aim of the study was to examine the relationship between concentric and isometric strength of knee flexors and extensors and postural stability in mild stage MS patients. Materials and Methods The study included 21 mild-stage MS patients with an EDSS score of 4 or less and 21 healthy controls. The concentric and isometric strength of knee flexors and extensors was measured with the Biodex System 4 Dynamometer, and postural stability with the Biodex Balance System under eyes-open and eyes-closed conditions on a rigid surface. Results Mild-stage MS patients had reduced concentric strength of knee extensors and flexors and increased postural sway compared with healthy controls (p < 0.05). Isometric strength of knee extensors and flexors in mild stage MS patients were similar to healthy controls (p > 0.05). There was a moderate positive correlation between concentric strength of knee extensors and flexors and isometric strength of knee flexors and open-eye postural stability indexes in mild stage multiple sclerosis patients (p < 0.05). Conclusions While isometric strength of knee extensors and flexors was preserved, concentric strength of knee extensors and flexors was decreased, and postural stability was adversely affected in mild stage MS patients. The increase in the strength of the knee muscles was associated with an increase in their postural sway in mild stage MS patients.Article Citation - WoS: 4Citation - Scopus: 4An Approach for Regime-Switching Stochastic Control Problems With Memory and Terminal Conditions(Taylor & Francis Ltd, 2026) Savku, E.In this research article, we focus on a stochastic optimal control problem with two types of terminal constraints. These specific conditions provide real-valued and stochastic Lagrange multipliers. Our model evolves according to a Markov regime-switching jump diffusion model with memory. In this context, the memory is represented by a Stochastic Differential Delay Equation. We present two theorems for each constraint within the general formulation of stochastic optimal control theory in a Lagrangian environment. We approach to this task from a theoretical perspective and provide mild technical assumptions, which make our theorems applicable for a broad class of stochastic control problems as well as for a wide range of disciplines such as engineering, biology, operations research, medicine, computer science and economics. In this work, we apply Stochastic Maximum Principle to demonstrate an optimal dividend policy corresponding to a time-delayed wealth process of a company. Moreover, we determine the real-valued Lagrange multiplier of this control problem explicitly.Article Citation - WoS: 5Citation - Scopus: 6Balance and Gait in Individuals With Diabetic Peripheral Neuropathy(Taylor & Francis Ltd, 2024) Korkusuz, Suleyman; Seckinogullari, Busra; Yuruk, Zeliha Ozlem; Ulug, Naime; Kibar, SibelBackground: Diabetic Peripheral Neuropathy (DPN) causes various physical problems such as the increased risk of falling, loss of balance and coordination while standing or walking, susceptibility to injuries due to sensory loss.Aims: The aim of the study was to evaluate and compare the effects of neuropathic pain (NP) in individuals with DPN on balance and gait.Methods: This prospective controlled study was conducted on 42 adults aged between 40-65 years. The participants were divided into three groups; individuals with DPN and NP (DPN+NP/n = 14), individuals with DPN without NP (DPN-NP/n = 14), and the control group (n = 14), respectively. The Force Plate system and Core Balance System measured static and dynamic postural balance and stability limits. Gait and dynamic plantar pressure distribution analyses were performed with a computerized gait evaluation system.Results: The score of LANSS, and VAS during gait were higher in DPN+NP group than in DPN-NP (p < 0.05). No significant difference was observed between the groups in balance parameters (p > 0.05). The right-left heel maximum forces were lower in both groups with DPN compared to the control group (p < 0.05). In terms of spatiotemporal parameters of the gait, there was a difference between the groups only in step width and left single support line parameters (p < 0.05).Conclusions: The results of this study indicate that the individuals with DPN have an increased step width, their left single support line was shortened, and the maximum force on the heel decreased. The NP did not cause any change in balance and gait parameters.Article Citation - WoS: 2Citation - Scopus: 1Memory and Anticipation: Two Main Theorems for Markov Regime-Switching Stochastic Processes(Taylor & Francis Ltd, 2025) Savku, E.We present two main theorems for stochastic processes with a Markov regime-switching model. First, we work on an existence-uniqueness theorem for a Stochastic Differential Delay Equation with Jumps and Regimes (SDDEJRs). Then we provide the duality between an SDDEJR and an Anticipated Backward Stochastic Differential Equation with Jumps and Regimes (ABSDEJRs). Our goal is to provide two technical and fundamental theorems for the future theoretical and applied developments of time-delayed and time-advanced models.