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Article Citation - WoS: 2Citation - Scopus: 2Social and Economic Indicators of Household Income in Turkey: Does Ethnicity Matter?(Springer, 2018) Toros, Emre; Cilasun, Seyit; Toros, AykutIn Turkey, the GDP per capita of eastern regions, where the Kurdish population is dense, is significantly lower than that of the rest of the country. The aim of this paper is to provide a quantitative analysis to investigate the contribution of household characteristics and regional disparities on racial/ethnic inequalities in household income, particularly across Turks and Kurds. Based on the results of regression-based decomposition analyses, there exist significant income differences between Turks and Kurds. However, this difference significantly diminishes if the household head is working. It is also observed that the household income increases with education, while decreases with migration and being settled in economically disadvantaged regions. Results also indicate that differential returns to Turks and Kurds on observable characteristics are lower in higher income quintilesArticle Citation - WoS: 27Citation - Scopus: 36Determination of Ca Addition To the Wheat Flour by Using Laser-Induced Breakdown Spectroscopy (libs)(Springer, 2016) Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Koksel, Hamit; Boyaci, Ismail HakkiThe aim of the study was to determine Ca addition to the flour by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple multi-elemental spectroscopy method. Different amounts of CaCO3-added wheat flour were analyzed using LIBS to determine Ca content and Ca/K ratio, which is used for discrimination of natural and Ca-added flour. LIBS spectra were quantitatively evaluated with partial least square (PLS) method as a multivariate data analysis method to eliminate the matrix effect. Ca and Ca/K calibration graphs of PLS method showed good linearity with coefficient of determinations (R (2)) 0.999. Limit of detection values for Ca and Ca/K analysis were calculated as 25.9 ppm and 0.013, respectively. Furthermore, the results were found to be consistent with the data obtained from atomic absorption spectroscopy method as a reference method for flour samples.Article Citation - WoS: 20Citation - Scopus: 19Electrical Characteristics of Organic Heterojunction With an Alternating Benzotriazole and Fluorene Containing Copolymer(Springer, 2020) Gullu, H. H.; Yildiz, D. E.; Toppare, L.; Cirpan, A.The current-voltage (I - V) and capacitance-voltage (C - V) characteristics of the organic heterojunction diode were investigated in a wide temperature range from 80 to 320 K and frequency range from 10 kHz to 1 MHz, respectively. Alternative to the copolymer partner poly(3-hexylthiophene) (P3HT) to [6,6]phenyl-C61-butyric acid methyl ester (PCBM), poly((9,9-dioctylfluorene)-2,7diyl-(4,7-bis(thien-2-yl)-2-dodecyl-benzo[1,2,3]triazole)) (named as copolymer in this work) was adapted to the bulk-heterojunction layer in the organic diode. Together with the use of Lif/Al bilayer electrode, the diode was fabricated as in the form of Al/LiF/copolymer:PCBM/PEDOT:PSS/ITO/glass. Under the applied bias voltage, this organic-based diode shows two- orders of magnitude rectifying behavior. According to thermionic emission (TE) model, the diode parameters such as saturation current, barrier height and ideality factor were determined and parasitic resistances were also extracted from the conventional ohmic relation. As to the temperature dependency of the diode parameters and their response to the temperature variation, barrier inhomogeneity, surface state and series resistance effects were found in dominant behavior on the current flow. The conduction mechanism was modeled by assuming low-barrier patches around the main barrier that supports TE at low temperatures and their distribution was expressed by a Gaussian function. In addition, series resistance values were detailed depending on temperature using Cheung's model. C - V analysis was performed to evaluate the distribution of surface states at the interface as a function of frequency. Based on the C - V plots, the effects of charges at these traps were observed especially at low frequencies. Additionally, from these results, Fermi level, surface potential and donor concentration values were evaluated in a wide frequency range.Article Citation - WoS: 6Citation - Scopus: 6Electrochemical Copolymerization and Characterization of Dianilines Linked by Polyether Bridge With Aniline(Springer, 2010) Tirkes, Seha; Onal, Ahmet M.Copolymer of aniline and triethylene glycol bis(o-aminophenyl) ether was synthesized by constant potential electrolysis. Cyclic voltammogram of the copolymer films recorded in the monomer-free electrolytic solution revealed that the redox behavior of the films approaches to that of poly(triethylene glycol bis(o-aminophenyl) ether) with increasing amount of triethylene glycol bis(o-aminophenyl) in the feed ratio. Copolymerization was investigated by in situ recording the changes in the electronic absorption spectrum during electrolysis. The free standing copolymer film was characterized utilizing Fourier transform infrared spectrometer, and spectroelectrochemical behavior of the copolymer was investigated via in situ UV-vis spectroscopic technique. Besides the electron spin resonance study of the copolymer film, the different morphologies of the polymers were examined by scanning electron microscopy and the copolymerization was confirmed. The temperature dependence conductivity of the copolymer film was measured by four-probe technique in the temperature range of 100-300 K, and the calculated parameters showed that conduction mechanism fits to variable range hopping.Article Citation - WoS: 5Citation - Scopus: 4Nickel Doping Effects on the Structural and Dielectric Properties of Ba(zn1/3< Perovskite Ceramics(Springer, 2021) Qasrawi, A. F.; Sahin, Ethem Ilhan; Emek, MehribanThe effects of nickel doping into Ba(Zn1/3Nb2/3)O-3 (acronym: BZN) ceramics is structurally, morphologically and electrically investigated. The nickel substitution in sites of Zn which was carried out by the solid state reaction technique strongly enhanced the structural, morphological and electrical performances of the BZN. Specifically, while the lattice constant and crystallite sizes increased, the microstrain and the defect density decreased. The relative density of the BZN ceramics increased from 95.40% to 98.24% upon doping of Ni with content of x = 0.05. In addition, the Ni doping increased the values of electrical conductivity without significant changes in the dielectric constant values. It is also observed that the doping the BZN ceramics highly altered the temperature dependent variation of the relative dielectric constant. In the temperature range of 293-473 K, the x = 0.05 Ni doped BZN samples were less sensitive to temperature. The dynamics of the temperature dependent dielectric response is dominated by the coupled defects excitation mechanisms. Both of the temperatures and frequency dependent dielectric constant, dielectric loss and electrical conductivity suggests that the Ni doped Ba(Zn1/3Nb2/3)O-3 ceramics is more appropriate for electronic device fabrication than the pure ones.Book Part A Niche-Based Perspective to Stem and Cancer Stem Cells of the Lung(Springer, 2025) Boyacıoğlu, Özge; Kalali, Berfin Deniz; Tongün, Ege; Korkusuz, PetekLungs carry the principle function for the conduction and exchange of air through the primary, secondary, tertiary bronchi, bronchioles, and alveoli, resulting in the exchange of oxygen to carbon dioxide within the human tissues. Lung stem and progenitor cells enable differentiation of parenchymal and stromal elements and provide homeostasis and regeneration in the microenvironment against pulmonary diseases. Tumor-initiating cancer cells (TICs) refer to a subpopulation named as cancer stem cells (CSCs) of lung cancer exhibiting high self-renewal and proliferation capacity by Notch, Hippo, Hedgehog, and Wnt signaling pathways that leads to tumor development or recurrence. Lung cancer stem cells (LCSCs) are characterized by distinct genotypic or phenotypic alterations compared to healthy lung stem cells (LSCs) that provide a potential target to treat lung cancer. Therefore, understanding the cascades responsible for the transformation of healthy to CSCs is essential to develop new targeted therapy approaches. In this chapter, we precisely highlight the latest researches on LSCs and CSCs, key signaling mechanisms within the perspective of novel targeted therapy strategies. © 2025 Elsevier B.V., All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Metaheuristic Optimization of Rotating Multilayer Composite Tubes Under Internal Heating and Pressure(Springer, 2022) Azad, Saeid Kazemzadeh; Akis, TolgaAlthough analysis/design of multilayer assemblies has been always an active field of research, works on the optimal design of rotating multilayer composite tubes are very limited. This paper addresses the design optimization of rotating multilayer composite tubes under internal heating and pressure. For determining the structural responses, analytical solutions are provided based on different boundary conditions. The automated selection of optimal material as well as thickness optimization of pressurized multilayer assemblies is carried out under different angular speed and internal heating conditions using a metaheuristic algorithm. The corresponding optimum design for each angular speed as well as internal heating condition is sought, and the numerical results are discussed. The study provides general guidelines for conceptual design of rotating multilayer composite tubes subjected to internal heating and pressure.Article Citation - WoS: 8Citation - Scopus: 8Temperature-Tuned Bandgap Characteristics of Bi12tio20< Sillenite Single Crystals(Springer, 2021) Isik, M.; Delice, S.; Gasanly, N. M.; Darvishov, N. H.; Bagiev, V. E.Bi12MO20 (M: Si, Ge, Ti, etc.) compounds are known as sillenites having fascinating photorefractive characteristics. The present paper reports the structural and optical characteristics of one of the members of this family, Bi12TiO20 single crystals, grown by Czochralski method. X-ray diffraction pattern of the crystal presented sharp and intensive peaks associated with planes of cubic crystalline structure with lattice constant of a = 1.0142 nm. The optical properties were studied by means of room temperature Raman and temperature-dependent transmission experiments at various temperatures between 10 and 300 K. Raman spectrum indicated peaks around 127, 162, 191, 219, 261, 289, 321, 497 and 537 cm(-1). The analyses of transmittance spectra indicated the increase of direct bandgap energy from 2.30 to 2.56 eV as temperature was decreased from room temperature to 10 K. The temperature-dependent bandgap characteristics of Bi12TiO20 were analyzed by means of Varshni and O'Donnell-Chen models. The analyses under the light of these models resulted in absolute zero bandgap energy of E-g(0) = 2.56(4) eV, rate of change of bandgap energy of gamma = - 1.11 x 10(-3) eV/K and average phonon energy of < E-ph & rang; = 8.6 meV.Article Citation - WoS: 22Citation - Scopus: 23Comparison of Different Synthesis Methods To Produce Lithium Triborate and Their Effects on Its Thermoluminescent Property(Springer, 2010) Depci, Tolga; Özbayoğlu, Gülhan; Ozbayoglu, Gulhan; Yilmaz, Aysen; Özbayoğlu, Gülhan; Energy Systems Engineering; Energy Systems EngineeringLithium triborate (LiB3O5) was produced by different synthesis methods, which included high-temperature solid-state reaction, microwave-assisted high-temperature solid-state reaction, and precipitation-assisted high-temperature solid-state reaction. After the synthesis, metal oxides (CuO and Al2O3) were doped into LiB3O5 to enhance its thermoluminescent (TL) properties, and the TL intensities were compared with each other. The identification and characteristics of undoped and doped LiB3O5 were determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, differential thermal analyses (DTA), scanning electron microscopy (SEM), and particle size analyzer. The glow curves were obtained by using a TL reader. The results showed that synthesis routes affected the physical and structural properties of lithium triborate, which have an important effect on its TL intensity.Article Citation - Scopus: 8Interpretation of the Λc(2910)+Baryon Newly Seen by Belle Collaboration and Its Possible Bottom Partner(Springer, 2022) Azizi, K.; Sarac, Y.; Sundu, H.The developments in the experimental facilities and analyses techniques have recently lead to the observation of many hadronic states ranging from excitations of conventional hadrons to various exotic states. The baryons with single heavy quark are among these states providing an attractive field of research to get a better understanding of the nonperturbative nature of the strong interaction. Recently, the Belle Collaboration announced observation of the state Lambda(c)(2910)(+) with a mass 2913.8 +/- 5.6 +/- 3.8 MeV/c(2) and width 51.8 +/- 20.0 +/- 18.8 MeV. In the present study, by the mass analyses of different excitations at Lambda(c) channel and their comparison with existing experimental information, we find that the spin-parity of this newly found excited state is J(P)=1/2(-) and it is a 2P state denoting by Lambda(c)(1/2(-), 2P). We predict its current coupling as well, which can be served as one of the main input parameters to investigate different decays and interactions of this particle. We also determine the mass and current coupling of Lambda(b)(1/2(-), 2P) as possible bottom counterpart of the new Lambda(c)(2910)(+) state, which may be in agenda of different experiments in near future.
