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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 Citation - WoS: 1Citation - Scopus: 1Machine Vs. Deep Learning Comparision for Developing an International Sign Language Translator(Taylor & Francis Ltd, 2022) Eryilmaz, Meltem; Balkaya, Ecem; Ucan, Eylul; Turan, Gizem; Oral, Seden GulayThis study aims to enable deaf and hard-of-hearing people to communicate with other individuals who know and do not know sign language. The mobile application was developed for video classification by using MediaPipe Library in the study. While doing this, considering the problems that deaf and hearing loss individuals face in Turkey and abroad modelling and training stages were carried out with the English language option. With the real-time translation feature added to the study individuals were provided with instant communication. In this way, communication problems experienced by hearing-impaired individuals will be greatly reduced. Machine learning and Deep learning concepts were investigated in the study. Model creation and training stages were carried out using VGG16, OpenCV, Pandas, Keras, and Os libraries. Due to the low success rate in the model created using VGG16, the MediaPipe library was used in the formation and training stages of the model. The reason for this is that, thanks to the solutions available in the MediaPipe library, it can normalise the coordinates in 3D by marking the regions to be detected in the human body. Being able to extract the coordinates independently of the background and body type in the videos in the dataset increases the success rate of the model in the formation and training stages. As a result of an experiment, the accuracy rate of the deep learning model is 85% and the application can be easily integrated with different languages. It is concluded that deep learning model is more accure than machine learning one and the communication problem faced by hearing-impaired individuals in many countries can be reduced easily.Article Citation - WoS: 6Effectiveness of Proprioceptive Neuromuscular Facilitation and Myofascial Release Techniques in Patients With Subacromial Impingement Syndrome(Taylor & Francis Ltd, 2022) Celik, Merve Sinem; Sonmezer, Emel; Acar, ManolyaPurpose To compare the effectiveness of proprioceptive neuromuscular facilitation and myofascial release technique in patients with subacromial impingement syndrome on pain, range of motion, muscle strength, quality of life, functionality and disability. Methods Thirty patients were randomly divided into two groups: proprioceptive neuromuscular facilitation group (n = 15) and proprioceptive neuromuscular facilitation combined with myofascial release technique group (n = 15). Both treatment methods were performed 3 times a week for 4 weeks. Pain severity was assessed by Visuel Analog Scale, range of motion by a goniometer, muscle strength by digital hand dynamometer, quality of life by Nottingham health profile, functionality by arm, shoulder and hand problems questionnaire, disability by shoulder pain and disability index. All measurements were used before and after treatments. Pain severity, range of motion and muscle strength were also evaluated after the first session. Results After the treatment, shoulder pain, range of motion, muscle strength, functionality and disability were improved in two groups (p < 0.05). Proprioceptive neuromuscular facilitation showed improvement in pain, whereas myofascial release technique improved pain, physical activity, emotional state, sleep and total dimensions of life quality (p < 0.05). Proprioceptive neuromuscular facilitation was more effective in reducing activity pain, whereas myofascial release technique was more effective in increasing flexion, external and internal rotation range of motion, flexion and abduction muscle strength after the first session (p < 0.05). Conclusions The combined application of proprioceptive neuromuscular facilitation and myofascial release technique has a more acute and cumulative positive effect on pain, range of motion, muscle strength, functionality, disability and quality of life in patients with subacromial impingement syndrome.Article Citation - WoS: 2Citation - Scopus: 2Cb65 and Novel Cb65 Liposomal System Suppress Mg63 and Saos-2 Osteosarcoma Cell Growth in Vitro(Taylor & Francis Ltd, 2024) Zorba, Basak Isil; Boyacioglu, Oezge; Caglayan, Tugba; Recber, Tuba; Nemutlu, Emirhan; Eroglu, Ipek; Korkusuz, PetekCurable approaches for primary osteosarcoma are inadequate and urge investigation of novel therapeutic formulations. Cannabinoid ligands exert antiproliferative and apoptotic effect on osteosarcoma cells via cannabinoid 2 (CB2) or transient receptor potential vanilloid type (TRPV1) receptors. In this study, we confirmed CB2 receptor expression in MG63 and Saos-2 osteosarcoma cells by qRT-PCR and flow cytometry (FCM), then reported the reduction effect of synthetic specific CB2 receptor agonist CB65 on the proliferation of osteosarcoma cells by WST-1 (water-soluble tetrazolium-1) and RTCA (real-time impedance-based proliferation). CB65 revealed an IC50 (inhibitory concentration) for MG63 and Saos-2 cells as 1.11 x 10(-11) and 4.95 x 10(-11) M, respectively. The specific antiproliferative effect of CB65 on osteosarcoma cells was inhibited by CB2 antagonist AM630. CB65 induced late apoptosis of MG63 and Saos-2 cells at 24 and 48 h, respectively by FCM when applied submaximal concentration. A novel CB65 liposomal system was generated by a thin film hydration method with optimal particle size (141.7 +/- 0.6 nm), polydispersity index (0.451 +/- 0.026), and zeta potential (-10.9 +/- 0.3 mV) values. The encapsulation efficiency (EE%) of the CB65-loaded liposomal formulation was 51.12%. The CB65 and CB65-loaded liposomal formulation releasing IC50 of CB65 reduced proliferation by RTCA and invasion by scratch assay and induced late apoptosis of MG63 and Saos-2 cells, by FCM. Our results demonstrate the CB2 receptor-mediated antiproliferative and apoptotic effect of a new liposomal CB65 delivery system on osteosarcoma cells that can be used as a targeted and intelligent tool for bone tumors to ameliorate pediatric bone cancers following in vivo validation.Article Citation - WoS: 23Citation - Scopus: 27Facile synthesis of CsPbBr3/PbSe composite clusters(Taylor & Francis Ltd, 2018) Thang Phan Nguyen; Ozturk, Abdullah; Park, Jongee; Sohn, Woonbae; Tae Hyung Lee; Jang, Ho Won; Kim, Soo YoungIn this work, CsPbBr3 and PbSe nanocomposites were synthesized to protect perovskite material from self-enlargement during reaction. UV absorption and photoluminescence (PL) spectra indicate that the addition of Se into CsPbBr3 quantum dots modified the electronic structure of CsPbBr3, increasing the band gap from 2.38 to 2.48 eV as the Cs:Se ratio increased to 1:3. Thus, the emission color of CsPbBr3 perovskite quantum dots was modified from green to blue by increasing the Se ratio in composites. According to X-ray diffraction patterns, the structure of CsPbBr3 quantum dots changed from cubic to orthorhombic due to the introduction of PbSe at the surface. Transmission electron microscopy and X-ray photoemission spectroscopy confirmed that the atomic distribution in CsPbBr3/PbSe composite clusters is uniform and the composite materials were well formed. The PL intensity of a CsPbBr3/PbSe sample with a 1:1 Cs: Se ratio maintained 50% of its initial intensity after keeping the sample for 81 h in air, while the PL intensity of CsPbBr3 reduced to 20% of its initial intensity. Therefore, it is considered that low amounts of Se could improve the stability of CsPbBr3 quantum dots.Article Citation - WoS: 9Citation - Scopus: 11Reducibility of Nickeliferous Limonitic Laterite Ore From Central Anatolia(Taylor & Francis Ltd, 2014) Pournaderi, S.; Keskinkilic, E.; Geveci, A.; Topkaya, Y. A.Limonitic nickel laterite from Sivrihisar reserve in Turkey was reduced at 700-1100 degrees C by the addition of 5.74, 8.61 and 11.48 wt-% coal under an argon atmosphere. The run-of-mine ore and the reduced samples were studied using X-ray diffraction. The metallisation of Fe was found to be limited up to 900 degrees C, but increased rapidly at higher temperatures. The metallisation of Ni and Co increased when the temperature was increased from 700 to 800 degrees C, almost levelled off up to 900 degrees C and then increased up to 1100 degrees C. The results also showed that increased coal additions did not affect Fe metallisation up to 900 degrees C. At 1000 degrees C the metallisation of Fe became slightly better, but its effect was more pronounced at 1100 degrees C. The increased coal addition affected the nickel reduction equally at all temperatures, while it had no effect on the metallisation of Co.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, 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: 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: 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.
