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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: 11Citation - Scopus: 11Higher 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: 3Citation - 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, Ozgur; Cakir Kabakci, GamzeRecycled 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: 13Structural, 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: 3Citation - Scopus: 4Predictive Rental Values Model for Low-Income Earners in Slums: the Case of Ijora, Nigeria(Taylor & Francis Ltd, 2023) Iroham, Chukwuemeka O.; Misra, Sanjay; Emebo, Onyeka C.; Okagbue, Hilary, IIt is well known most often that values of properties tend to hike at the effluxion of time. This has necessitated the adoption of predictive models in interpreting outcomes in the property market in the future. Earlier studies have been oblivious of such models' outcomes as it affects any focal group, particularly the vulnerable. This present study focuses on the low-income earners found in the slum. The Ijora community in Lagos was the highlight of this study, particularly Ijora Badia and Ijora Oloye, regarded as slums according to the UNDP report. The entire fifty-two (52) local agents in the Ijora community were surveyed in cross-sectional survey research that entailed the questionnaire's issuance. The nexus of data collection, pre-processing, data analysis, algorithm application, and model evaluation resulted in retrieving rental values within the years 2010 and 2019 on two predominant residential property types of self-contain and one-bedroom flats found within the community. Three selected algorithms, Artificial Neural Network (ANN), Support Vector Machine, and Logistic Regression, were essentially used as classifiers but trained to predict the continuous values. These algorithms were implemented through the use of Python's SciKit-learn Library and RapidMiner. The findings revealed that though all three models gave accurate predictions, Logistic Regression was the highest with low error values. It was recommended that Logistic Regression be applied but with much data set of property values of low-income earners over much more period. This study will contribute to the Sustainable development goals(SDG) 11(Sustainable cities and communities) of the United Nations to benefit developing countries, especially in sub-Saharan Africa.Review Citation - WoS: 18Citation - Scopus: 24A Literature Review on Mhe Selection Problem: Levels, Contexts, and Approaches(Taylor & Francis Ltd, 2015) Saputro, Thomy Eko; Masudin, Ilyas; Rouyendegh (Babek Erdebilli), Babak Daneshvar; Rouyendegh , Babak DaneshvarThis paper presents a review on selection problem of material handling equipment (MHE) and general equipment used in industry area. The issue on MHE is widely paid attention since MHE has contribution on material, good and product accomplishment. Few methods and softwares have been proposed and developed to select the most appropriate MHE for a complex selection problem. Today's high diverisity of MHE categories and types influence the generation of many possible choices which leads to the complexity. In this paper, a further discussion in terms of MHE and equipment including three major points namely level of selection, the context of selection problem and the approaches are served to highlight the complex MHE selection according to the number of possible choices provided, to analyse the consideration for the problem context, and to reveal the superior method for complex MHE selection. Forty-two papers collected from the past study are presented asscociating each point of the discussion.Review Citation - WoS: 10Citation - Scopus: 10Latest Developments in Engineered Skeletal Muscle Tissues for Drug Discovery and Development(Taylor & Francis Ltd, 2023) Ostrovidov, Serge; Ramalingam, Murugan; Bae, Hojae; Orive, Gorka; Fujie, Toshinori; Shi, Xuetao; Kaji, HirokazuIntroductionWith the advances in skeletal muscle tissue engineering, new platforms have arisen with important applications in biology studies, disease modeling, and drug testing. Current developments highlight the quest for engineering skeletal muscle tissues with higher complexity . These new human skeletal muscle tissue models will be powerful tools for drug discovery and development and disease modeling.Areas coveredThe authors review the latest advances in in vitro models of engineered skeletal muscle tissues used for testing drugs with a focus on the use of four main cell culture techniques: Cell cultures in well plates, in microfluidics, in organoids, and in bioprinted constructs. Additional information is provided on the satellite cell niche.Expert opinionIn recent years, more sophisticated in vitro models of skeletal muscle tissues have been fabricated. Important developments have been made in stem cell research and in the engineering of human skeletal muscle tissue. Some platforms have already started to be used for drug testing, notably those based on the parameters of hypertrophy/atrophy and the contractibility of myotubes. More developments are expected through the use of multicellular types and multi-materials as matrices . The validation and use of these models in drug testing should now increase.Article Post-Hoc Mixture Models to eBLUPs from Linear Mixed-Effects Models: A Tractable Approach for Clustering Irregular Longitudinal Data(Taylor & Francis Ltd, 2026) Balakrishnan, N.; Hossain, Md JobayerClustering longitudinal data with irregular and sparse measurement schedules has become important in analyzing many medical data and associated decision-making. These datasets often involve observation times that vary across individuals, making trajectory-based analysis essential for uncovering meaningful patterns. Mixture-based linear mixed-effects models, such as heterogeneous linear mixed-effects models and growth mixture modeling, are commonly used for this purpose. While theoretically powerful, these methods often suffer from convergence issues and computational inefficiency in large-scale applications. This study introduces a computationally efficient two-step approach that applies a post-hoc mixture model to empirical Best Linear Unbiased Predictors (eBLUPs), derived from a fitted (piecewise) linear mixed-effects model under homogeneity assumptions. The method is then demonstrated with real clinical data, in which it effectively identified distinct growth trajectories in early childhood data involving 3,365 children across 51,711 clinic visits. The optimal number of clusters is then selected using the BIC, likelihood ratio tests, and model-based validation, achieving the best balance of model fit, classification stability, and interpretability. Simulation studies have shown that eBLUPs preserve individual-level heterogeneity and that post-hoc mixture modeling outperforms HLME across varying separability. Overall, this approach offers a robust, interpretable, and scalable alternative to traditional clustering methods for irregular longitudinal data.Article Citation - WoS: 18Citation - Scopus: 18A New Outlier Detection Method Based on Convex Optimization: Application To Diagnosis of Parkinson's Disease(Taylor & Francis Ltd, 2021) Taylan, Pakize; Yerlikaya-Ozkurt, Fatma; Bilgic Ucak, Burcu; Weber, Gerhard-WilhelmNeuroscience is a combination of different scientific disciplines which investigate the nervous system for understanding of the biological basis. Recently, applications to the diagnosis of neurodegenerative diseases like Parkinson's disease have become very promising by considering different statistical regression models. However, well-known statistical regression models may give misleading results for the diagnosis of the neurodegenerative diseases when experimental data contain outlier observations that lie an abnormal distance from the other observation. The main achievements of this study consist of a novel mathematics-supported approach beside statistical regression models to identify and treat the outlier observations without direct elimination for a great and emerging challenge in humankind, such as neurodegenerative diseases. By this approach, a new method named as CMTMSOM is proposed with the contributions of the powerful convex and continuous optimization techniques referred to as conic quadratic programing. This method, based on the mean-shift outlier regression model, is developed by combining robustness of M-estimation and stability of Tikhonov regularization. We apply our method and other parametric models on Parkinson telemonitoring dataset which is a real-world dataset in Neuroscience. Then, we compare these methods by using well-known method-free performance measures. The results indicate that the CMTMSOM method performs better than current parametric models.Article Citation - WoS: 2Citation - Scopus: 2Influence of Surface Finish on Flexural Strength and Microhardness of Indirect Resin Composites and the Effect of Thermal Cycling(Taylor & Francis Ltd, 2012) Bicer, Arzu Zeynep Yildirim; Dogan, Arife; Dogan, Orhan Murat; Sengonul, Merih Cemal; Artvin, Zafer; Yildirim Bicer, Arzu ZeynepThis study investigated the effect of surface finish and thermal cycling procedures on flexural strength and surface microhardness of three indirect resin composites, Artglass (R), Signum (R), and Solidex (R). The specimens were prepared in sufficient number and size according to flexural and microhardness test requirements (n=10). Scanning electron microscopy-energy dispersive x-ray (SEM-EDX) analysis was also used for studying the morphology, dispersion, and elemental compositions of fillers. The EDX results showed that Artglass contained 1.57% aluminium oxide (Al2O3), 53.29% silicon dioxide (SiO2), and 2.62% barium oxide (BaO); Signum had 55.69% silicon dioxide (SiO2) and Solidex had 44.99% silicon dioxide (SiO2) of total mass. Artglass appeared to display the best flexural strength values under all the test conditions employed (range: 116.8 +/- 32.18 to 147.8 +/- 47.97 MPa), and it was followed by Signum (range: 93.7 +/- 22.84 to 118.0 +/- 33.45 MPa). Thermal cycling did not seem to have affected the flexural strength of Artglass and Signum (p > 0.05); however, it led to a significant decrease, from (110.5 +/- 20.69 MPa) to 74.0 +/- 13.30 MPa (p < 0.001), in the strength of polished Solidex specimens. While surface microhardness of the three materials increased by polishing ( Artglass: 55.7 +/- 2.64/74.1 +/- 8.63 Vickers Hardness Numbers (VHN); Signum: 44.8 +/- 3.12/60.7 +/- 4.50 VHN; Solidex: 44.0 +/- 2.31/53.4 +/- 3.58 VHN for unpolished/polpolished specimens), thermal cycling had a deleterious effect on this property (p < 0.001).
