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Article Citation - WoS: 1Citation - Scopus: 3Spectral Approach To Derive the Representation Formulae for Solutions of the Wave Equation(Hindawi Publishing Corporation, 2012) Guseinov, Gusein Sh.Using spectral properties of the Laplace operator and some structural formula for rapidly decreasing functions of the Laplace operator, we offer a novel method to derive explicit formulae for solutions to the Cauchy problem for classical wave equation in arbitrary dimensions. Among them are the well-known d'Alembert, Poisson, and Kirchhoff representation formulae in low space dimensions.Conference Object Kinetics Studies on Glyceraldehyde Concentration of Bovine Lens Aldose Reductase(Wiley-blackwell, 2011) Onay, M.; Onay, M.; Coruh, N.; Isgor, S. B.[No Abstract Available]Article Citation - WoS: 11Citation - Scopus: 12Structural and Temperature-Tuned Bandgap Characteristics of Thermally Evaporated β-in2< Thin Films(Springer, 2021) Surucu, O.; Isik, M.; Terlemezoglu, M.; Gasanly, N. M.; Parlak, M.In2S3 is one of the attractive compounds taking remarkable interest in optoelectronic device applications. The present study reports the structural and optical characteristics of thermally evaporated beta-In2S3 thin films. The crystalline structure of the thin films was found as cubic taking into account the observed diffraction peaks in the X-ray diffraction pattern. The atomic compositional ratio of constituent elements was obtained as consistent with chemical formula of In2S3. Three peaks around 275, 309 and 369 cm(-1) were observed in the Raman spectrum. Temperature-tuned bandgap energy characteristics of the In2S3 thin films were revealed from the investigation of transmittance spectra obtained at various temperatures between 10 and 300 K. The analyses of the transmittance spectra indicated that direct bandgap energy of the In2S3 thin films decreases from 2.40 eV (at 10 K) to 2.37 eV (at 300 K) with the increase of measurement temperature. The bandgap energy vs. temperature relation was investigated by means of Varshni optical model. The fitting of the experimental data under the light of theoretical expression revealed the absolute zero bandgap energy, the rate of change of bandgap energy and Debye temperature.Article Citation - WoS: 6Citation - Scopus: 5The Effect of Zn Concentration on the Structural and Optical Properties of Cd1-xznx< Nanostructured Thin Films(Springer, 2021) Isik, M.; Terlemezoglu, M.; Isik, S.; Erturk, K.; Gasanly, N. M.The structural and optical properties of electrodeposited Cd1-xZnxS nanostructured thin films were investigated in the present paper for compositions of x = 0, 0.03, 0.06 and 0.09. X-ray diffraction patterns of the deposited thin films consisted of diffraction peaks related to cubic crystal lattice. The atomic compositional ratios were determined by performing energy dispersive spectroscopy measurements. Scanning electron microscopy images indicated that deposited thin films have nanostructured forms. Raman spectra of the Cd1-xZnxS thin films exhibited two vibrational modes associated with longitudinal optical mode and its first overtone. Transmission measurements were performed on the deposited thin films to get their band gap energies. It was seen from the analyses of absorption coefficient that band gap energy of Cd1-xZnxS thin films increases almost linearly from 2.40 to 2.51 eV as the composition was increased from x = 0 to x = 0.09.Article Citation - WoS: 7Citation - Scopus: 7Surface Plasmon Resonance Aptasensor for Soluble Icam-1 Protein in Blood Samples(Royal Soc Chemistry, 2022) Dursun, Ali Dogan; Dogan, Soner; Kavruk, Murat; Tasbasi, B. Busra; Sudagidan, Mert; Yilmaz, M. Deniz; Tuna, Bilge G.Intercellular Adhesion Molecule-1 (ICAM-1) is considered to be a cancer biomarker in the assessment of metastatic potential in patients and an early indicator of atherosclerosis. A labelless biosensor based on the surface plasmon resonance (SPR) signal from the specific affinity interaction of an aptamer and a soluble ICAM-1 protein was developed for blood samples. The developed aptasensor provided real-time information on the concentration of the ICAM-1 protein in blood when integrated to a purification step based on a magnetic pull-down separation. The SPR aptasensor was highly specific with a limit of detection of 1.4/0.2 ng ml(-1), which was achieved through aptamer-functionalized silica-coated magnetic nanoparticles.Article Citation - WoS: 18Citation - Scopus: 21Musculoskeletal Pain, Related Factors, and Posture Profiles Among Adolescents: a Cross-Sectional Study From Turkey(Elsevier Science inc, 2021) Ozdemir, Serpil; Gencbas, Dercan; Tosun, Betul; Bebis, Hatice; Sinan, OzlemPurpose: The aim of the study was to evaluate musculoskeletal pain due to mechanical reasons and related risk factors in adolescents and to define posture profiles of adolescents. Design: A cross-sectional study. Methods: The study was conducted with 2221 adolescents between February 2015 and May 2015. The questionnaire used to collect data consisted of three parts: (1) descriptive characteristics of the participants, (2) pain assessment of 14 parts of the body, and (3) Back Pain and Body Posture Evaluation Instrument (BackPEI). Results: The prevalence of low back pain among the participants was 73.3% (n = 1,343), while the prevalence of back pain was 68.4% (n = 1,254). The participants attributed their pain to their poor sitting postures at school (38.1%, n = 847) and carrying school backpacks (84.1%, n = 1,713). There was a statistically significant difference in the physical activities of adolescents and the BackPEI score (z = 4.40; p = .001). Posture factors of the BackPEI score increased while school desk comfort score increased (Spearman's rho = 0.148; p = .001), but it decreased while the school grades of the adolescents increased (Spearman's rho [rho] = -0.161; p = .001). Conclusions: According to this study, body posture was related to musculoskeletal pain and was correlated with physical activities, school desk comfort, and school grades of the adolescents. It is suggested that correct posture and ergonomic positions should be taught to adolescents when using computers, carrying school backpacks, and sitting in school chairs to prevent musculoskeletal pain. (C) 2020 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 5Dispersive Optical Constants of Tl2ingase4< Single Crystals(Iop Publishing Ltd, 2007) Qasrawi, A. F.; Gasanly, N. M.The structural and optical properties of Bridgman method grown Tl2InGaSe4 crystals have been investigated by means of room temperature x-ray diffraction, and transmittance and reflectance spectral analysis, respectively. The x-ray diffraction technique has shown that Tl2InGaSe4 is a single phase crystal of a monoclinic unit cell that exhibits the lattice parameters of a = 0.77244 nm, b = 0.64945 nm, c = 0.92205 nm and beta = 95.03 degrees . The optical data have revealed an indirect allowed transition band gap of 1.86 eV. The room temperature refractive index, which was calculated from the reflectance and transmittance data, allowed the identification of the dispersion and oscillator energies, static dielectric constant and static refractive index as 28.51 and 3.45 eV, 9.26 and 3.04, respectively.Article Citation - WoS: 13Citation - Scopus: 12Novel Global Robust Stability Criterion for Neural Networks With Delay(Pergamon-elsevier Science Ltd, 2009) Singh, Vimal; Sıngh, Vımal; Sıngh, Vımal; Department of Mechatronics Engineering; Department of Mechatronics EngineeringA novel criterion for the global robust stability of Hopfield-type interval neural networks with delay is presented. An example illustrating the improvement of the present criterion over several recently reported criteria is given. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 42Citation - Scopus: 41Analysis of Forward and Reverse Biased Current-Voltage Characteristics of Al/Al2< Schottky Diode With Atomic Layer Deposited Al2o3< Thin Film Interlayer(Springer, 2019) Gullu, H. H.; Yildiz, D. E.The dark current-voltage (I-V) characteristics of Al/Al2O3/n-Si Schottky diode are investigated in a wide temperature range of 260-360 K. The diode shows four orders of magnitude rectification. In forward and reverse bias regions, the temperature-dependent I-Vcharacteristics are detailed in terms of diode parameters and dominant conduction mechanisms. Due to the existence of Al2O3 film layer and series resistance in the diode structure, current flow under the forward bias is observed in a deviation from pure exponential characteristics. The diode parameters are estimated from thermionic emission model with non-unity ideality factor, and this non-ideal behavior is resulted in the ideality factors greater than two. In addition to these values, zero-bias barrier height is found to be strongly temperature dependent, and this variation indicates a presence of inhomogeneties in the barrier according to Gaussian distribution (GD) approximation. This fact is investigated plotting characteristic plot of this model and by extracting mean barrier height with its standard deviation. In order to complete the work on the forward I-V region, the carrier transport characteristics of the diode are explained on the basis of thermionic emission mechanism with a GD of the harrier heights. In accordance with this approximation, the conventional Richardson plot exhibits non-linearity behavior and modified current relation based on GD model is used to calculate mean barrier height and Richardson constant. In addition, the values of parasitic resistances are determined using Ohm's law as a function of temperature for all bias voltage spectra. In the reverse bias region, Poole-Frenkel effect is found to be dominant on the conduction associated with the barrier lowering, and barrier height in the emission process from the trapped states, and high-frequency dielectric constant of Al2O3 film layer is calculated.Editorial Citation - Scopus: 1The Playmaker of the Mitral Valve Disease: Mitral Annulus(Elsevier Ireland Ltd, 2020) Karaduman, Bilge Duran; Ayhan, Huseyin; Keles, Telat; Bozkurt, Engin[No Abstract Available]
