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Öğe Anaphylaxis in pediatric patients: a multi-center, retrospective, case study(WILEY, 2009) Orhan, F.; Boz, Bingol A.; Yilmaz, O.; Reisli, I; Cakir, M.; Karakas, T.; Yuksel, H.[Abstract not Available]Öğe Characteristics and prognosis of childhood atopic dermatitis: a multi-center study in Turkey(WILEY-BLACKWELL PUBLISHING, INC, 2009) Yuksel, H.; Can, D.; Reisli, I; Uzuner, N.; Orhan, F.; Cevit, O.; Tahan, F.[Abstract not Available]Öğe Edge state distribution in an Aharonov-Bohm electron interferometer in the integer quantum Hall regime(IOP PUBLISHING LTD, 2011) Ozturk, T.; Kavruk, A. E.; Ozturk, A.; Atav, U.; Yuksel, H.In this study we analyze the density distributions of the two dimensional electron system for an experimental geometry which is topologically equivalent of an Aharonov-Bohm interferometer in three dimensions in the quantum Hall regime and obtain the spatial distribution of the edge states. We employ the Thomas-Fermi approximation in our analysis and solve the Poisson equation in three dimensional using a multi grid technique. Also we obtain the distribution of incompressible strips for a wide range of magnetic fields strengths and comment on their relation with experimental results in literature.Öğe EPR study of gamma irradiated 2,5-di-tert-butyl-hydroquinone single crystals(PERGAMON-ELSEVIER SCIENCE LTD, 2011) Sayin, U.; Dereli, O.; Turkkan, E.; Yuksel, H.; Birey, M.gamma-irradiated single crystals of 2,5-di-tert-butyl-hydroquinone (DTBHQ) were investigated using the electron paramagnetic resonance (EPR) technique. The spectra of the crystals at different orientations in the magnetic field between temperatures of 120 and 450 K, were found to be temperature dependent. Taking into consideration the chemical structure and the experimental spectra of the irradiated single crystals of DTBHQ we assumed that one or more paramagnetic species were produced, each having an unpaired electron delocalized in the phenyl ring. Pursuant to this assumption, four possible radicals were modeled using the B3LYP/6-31+G(d) level of density-functional theory. EPR parameters were calculated for these modeled radicals using the B3LYP method and TZVP basis set. The calculated hyperfine-coupling constants were used as starting points for simulations. The experimental and simulated spectra for each of the three crystallographic axes were well matched for the modeled radical R4; we thus identified the hydroquinone anion radical as a paramagnetic species produced in DTBHQ. The experimental g-factor of the hydroquinone anion radical were found to be anisotropic with the average value g(iso)=2.0096. The hyperfine coupling constants of the H-alpha proton was found anisotropic with the average value (a(H7)(alpha))(iso) = 6.3 G and H-beta proton was found isotropic with the average value (a(H8)(beta))= 3.5 G. (C) 2010 Elsevier Ltd. All rights reserved.Öğe EPR study of gamma-irradiated amphi-phenylglyoxime single crystals(PERGAMON-ELSEVIER SCIENCE LTD, 2011) Dereli, O.; Turkkan, E.; Ozmen, A.; Yuksel, H.Gamma-irradiated single crystals of Amphi-phenylglyoxime (APGO) were investigated using electron paramagnetic resonance (EPR) at different orientations in a magnetic field at room temperature (298 K). Considering the chemical structure and the experimental spectra of the irradiated single-crystals of APGO, we assumed that two different paramagnetic species, labeled as R* and R**, are either two iminoxy radicals formed by the abstraction of a H atom from different oxime branches or are different conformations of an iminoxy radical. Pursuant to this assumption, RA- and RB-type iminoxy radicals were modeled by the abstraction of H atoms from different oxime branches, and conformational analysis of these modeled radicals was performed using the semi-empirical AM1 and B3LYP/6-31 +G(d,p) methods. EPR parameters were calculated for the modeled radicals using the B3LYP method and EPR-III basis set. Theoretically calculated values of the most stable conformers (RA-1 and RB-1) of the modeled radicals are in good agreement with the experimental EPR parameters determined from the spectra (differences in isotropic hyperfine coupling constant values <5%, and differences in isotropic g values fall into 1 ppt). Thus, from the findings of the present study, we strongly suggest that the experimentally observed R* and R** radicals in the single crystal of amphi-phenylglyoxime are the most stable conformers of RA- and RB-type modeled iminoxy radicals, respectively. The experimental g factors and hyperfine coupling constants were found to be anisotropic, with average values of g=2.0052, A(N-14)=29.50 G, A(H-1)=25.30 G for R*, and g=2.0057, A(N-14)=34.50 G for R**. (C) 2011 Elsevier Ltd. All rights reserved.Öğe Influence of education on primary care physicians' knowledge on childhood allergy as a systemic disease and the atopic march(ELSEVIER DOYMA SL, 2011) Yilmaz, O.; Reisli, I.; Tahan, F.; Orhan, F.; Boz, A. B.; Yuksel, H.Background: There are many educational events for physicians in different countries covering one or some of the allergic diseases. Most of these educational events have been reported to improve care by the physicians. The aim of this study was to determine the baseline knowledge of general practitioners (GP) regarding the systemic nature of childhood allergy and atopic march, and to assess the influence of an educational event on this baseline knowledge. Methods: Two hundred and two GPs from five different cities in Turkey who attended education seminars were enrolled. All GPs were received the questionnaire both before and after the seminar. The questionnaire had statements about the systemic nature of childhood allergies and the atopic march, and GPs were asked to mark their degree of agreement as (completely true, partially true, wrong). Results: Mean age of GPs was 38.6 +/- 6.0 years. Mean duration after graduation from medical faculty was 13.9 +/- 6.5 years. There was significant improvement in answers after education. The statement "Frequency of allergic rhinitis and asthma is not as high as expected in children with atopic dermatitis" was regarded "wrong" by 60.9% but increased to 94.3% after the education (p < 0.001). Systemic nature of allergy was approved by 72.8%, which increased to 99% after the education (p < 0.001). Adrenalin as first line treatment in anaphylaxis treatment was appreciated by a higher number of GPs with the education (p<0.001). Conclusion: Many GPs lack updated information about the systemic nature of paediatric allergic diseases and a single educational event may improve their knowledge significantly. (C) 2010 SEICAR Published by Elsevier Espana, S.L. All rights reserved.Öğe Influence of postgraduate education on the knowledge of primary care physicians on childhood allergy and the allergic march as a systemic disease(WILEY-BLACKWELL PUBLISHING, INC, 2009) Yilmaz, O.; Reisli, I; Tahan, F.; Orhan, F.; Boz, Bingol A.; Yuksel, H.[Abstract not Available]Öğe Radiation Damage Centers in Cholesteryl Heptanoate(POLISH ACAD SCIENCES INST PHYSICS, 2013) Sayin, U.; Can, C.; Turkkan, E.; Dereli, O.; Ozmen, A.; Yuksel, H.Cholesterol takes part significantly in many biological mechanisms and as important component for manufacture of bile acids, steroid hormones, and several fat-soluble vitamins. To determine magnetic properties of cholesteryl heptanoate (C34H58O2) which is an important cholesteryl ester in human life and new technology, the single crystals of cholesteryl heptanoate were grown by slow evaporation of concentrated ethyl acetate solution and the grown single crystals were irradiated at room temperature with Co-60 gamma ray. The radical produced by gamma irradiation has been investigated in the range of temperatures 123-330 K for different orientations of the crystal in a magnetic field by EPR. Radiation damage center was attributed to radical (C) over dotH(alpha)CH(2 beta). The g factor and hyperfine coupling constants have slight dependence on temperature and evident dependence on the orientation of the magnetic field. Determined g factor and hyperfine coupling constants for the radical (C) over dotH(alpha)CH(2 beta) were found to be anisotropic with the average values g(av) = 2.0036, (a(CH alpha))(av) = 14.52 G, (a(CH2 beta))(av) = 25.78 G.Öğe The self-consistent calculation of the edge states in bilayer quantum Hall bar(IOP PUBLISHING LTD, 2011) Kavruk, A. E.; Ozturk, T.; Ozturk, A.; Atav, U.; Yuksel, H.In this study, we present the spatial distributions of the edge channels for each layer in bilayer quantum Hall bar geometry for a wide range of applied magnetic fields. For this purpose, we employ a self-consistent Thomas-Fermi-Poisson approach to obtain the electron density distributions and related screened potential distributions. In order to have a more realistic description of the system we solve three dimensional Poisson equation numerically in each iteration step to obtain self consistency in the Thomas-Fermi-Poisson approach instead of employing a "frozen gate" approximation.
