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Öğe Appropriateness of the current guidelines on reperfusion treatment for patients applying to our hospital with ST-segment elevation acute myocardial infarction(2012) Karaarslan Ş.; Alihanoglu Y.I.; Yildiz B.S.; Sönmez O.; Soylu A.; Bacaksiz A.; Düzenli A.Objectives: This study investigated the appropriateness of treatment for patients admitted with ST-segment elevation myocardial infarction (STEMI) according to the current guidelines. We also aimed to determine in-patient and out-patient factors affecting optimal re perfusion therapy. Study design: The reperfusion therapy of 176 patients with STEMI was determined. The time period from first contact with a healthcare provider to the time of balloon inflation (door to balloon time), and from the time period of first contact with a healthcare provider to the time of initiation of a thrombolytic (door to needle time) were calculated. Similarly, the time from admission at the emergency service (ES) of our hospital after referral to the moment of balloon inflation (ES to balloon time) and the period from admission to ES at our hospital to the moment of initiation of a thrombolytic (ES to needle time) were calculated. In order to determine the amount of in-hospital delay, the time from ES admission to the call to the cardiology department and the time for the cardiologist to evaluate the patient and transfer time were recorded. Whether the referring physician was a cardiologist and the effect of work hours on the reperfusion period was also recorded. Results: The door to balloon time in the referred patient group was calculated as an average of 228 minutes, while the time for patients directly admitted to ES was calculated as an average of 98 minutes. Patients referred for the mechanical reperfusion period compared to American Heart Association (AHA) guidelines consisted of only 6% of the eligible patients, while according to the European Society of Cardiology (ESC) guidelines 13% of patients were appropriate. Patients who were directly admitted to ES, experienced rates according to AHA guidelines and 73% experienced these rates according to ESC guidelines. We also found no significant effect of working hours or referring physician's specialty (cardiologist or other) on reperfusion time. Conclusion: Compliance rates of reperfusion therapy for patients presenting with STEMI was very low. We realized, when taking into consideration the reasons for delay in terms of both health community and the policy of the country, it is obvious that we have to take strict measures. © 2012 Turkish Society of Cardiology.Öğe Calculations on the half-lives of Cluster decay in two-potential approach(World Scientific Publishing Co. Pte Ltd, 2018) Soylu A.The half-lives of the cluster decay (CD) from the isotopes having the known experimental values, the half-lives of the ?-decay (AD) of same nuclei and also the branching ratios are obtained, within the framework of two-potential approach with cosh potential including with and without the isospin effects. Using two-potential approach and taking into account the isospin effects in the calculations decrease the rms values and they improve the results. The obtained branching ratios are in good agreement with the experimental ones for some isotopes. It is obtained that the isospin-dependent potentials have an influence on the half-lives of the cluster decays of nuclei. Present calculations would be important for predicting the experimental half-lives and branching ratios for the cluster decays of different types of isotopes. © 2018 World Scientific Publishing Company.Öğe Confinement control mechanism for two-electron Hulthen quantum dots in plasmas(Institute of Physics Publishing, 2018) Bahar M.K.; Soylu A.In this study, for the first time, the energies of two-electron Hulthen quantum dots (TEHQdots) embedded in Debye and quantum plasmas modeled by the more general exponential cosine screened Coulomb (MGECSC) potential under the combined influence of electric and magnetic fields are investigated by numerically solving the Schrödinger equation using the asymptotic iteration method. To do this, the four different forms of the MGECSC potential, which set through the different cases of the potential parameters, are taken into consideration. We propose that plasma environments form considerable quantum mechanical effects for quantum dots and other atomic systems and that plasmas are important experimental arguments. In this study, by considering the quantum dot parameters, the external field parameters, and the plasma screening parameters, a control mechanism of the confinement on energies of TEHQdots and the frequency of the radiation emitted by TEHQdots as a result of any excitation is discussed. In this mechanism, the behaviors, similarities, the functionalities of the control parameters, and the influences of plasmas on these quantities are explored. © 2018 IOP Publishing Ltd.Öğe Investigation of deformation effects on the decay properties of 12C+?Cluster states in 16O(Academic Press Inc., 2018) Soylu A.; Koyuncu F.; Coban A.; Bayrak O.; Freer M.We have analyzed the elastic scattering angular distributions data of the ?+12C reaction over a wide energy range (Elab=28.2 to 35.5 MeV) within the framework of the Optical Model formalism. A double folding (DF) type real potential was used with a phenomenological Woods–Saxon-squared (WS2) type imaginary potential. Good agreement between the calculations and experimental data was obtained. By using the real DF potential we have calculated the properties of the ?-cluster states in 16O by using the Gamow code as well as the ?-decay widths by using the WKB method. We implemented a 12C+? cluster framework for the calculation of the excitation energies and decay widths of 16O as a function of the orientation of the planar 12C nucleus with respect to the ?-particle. These calculations showed strong sensitivity of the widths and excitation energies to the orientation. Branching ratios were also calculated and though less sensitive to the 12C orientation, it was found that 12Cgs+? structure, with the ?-particle orbiting the 12C in its ground state, is dominant. This work demonstrates that deformation, and the orientation, of 12C plays a crucial role in the understanding of the nature of the ?-cluster states in 16O. © 2018 Elsevier Inc.Öğe Investigation of Sub-Coulomb barrier fusion reaction of ? + 4 0 Ca in different models(World Scientific Publishing Co. Pte Ltd, 2017) Koyuncu F.; Soylu A.In this study, microscopic nucleon-nucleon Double Folding (DF) and phenomenological potentials have been used to investigate ? +40Ca reaction observables at sub-barrier energies. In the calculations, semi-classical Wentzel-Kramers-Brillouin (WKB) approach has been used in order to obtain the cross-sections and reaction rates of ? +40Ca. Besides WKB approximation, we have also utilized Talys code in order to get the comparative results and find out the method differences. To estimate the reaction rates, energy-dependent cross-sections and astrophysical S-factors of ?+40Ca have been used. Herewith, differences between models and potentials have been demonstrated using the reaction rate estimates. © 2017 World Scientific Publishing Company.Öğe Kappa state solutions of Dirac-Hulthén and Dirac-Eckart problems with pseudospin and spin symmetry(American Institute of Physics Inc., 2008) Soylu A.; Bayrak O.; Boztosun I.In this study, the analytical solutions of the Dirac equation have been presented for the Hulthén and Eckart potentials by applying an approximation to centrifugal-like term in the case of spin symmetry, ?(r)=C=constant, and pseudospin symmetry, ?(r)=C=constant, for any spin-orbit quantum number K. The energy eigenvalues and corresponding spinor wave functions are obtained in the closed-forms. © 2008 American Institute of Physics.Öğe Laser-driven two-electron quantum dot in plasmas(American Institute of Physics Inc., 2018) Bahar M.K.; Soylu A.We have investigated the energies of two-electron parabolic quantum dots (TEPQdots) embedded in plasmas characterized by more general exponential cosine screened Coulomb (MGECSC) potential under the action of a monochromatic, linearly polarized laser field by solving the corresponding Schrödinger equation numerically via the asymptotic iteration method. The four different cases of the MGECSC potential constituted by various sets of the potential parameters are reckoned in modeling of the interactions in the plasma environments which are Debye and quantum plasmas. The plasma environment is a remarkable experimental argument for the quantum dots and the interactions in plasma environments are different compared to the interactions in an environment without plasma and the screening specifications of the plasmas can be controlled through the plasma parameters. These findings constitute our major motivation in consideration of the plasma environments. An appreciable confinement effect is made up by implementing the laser field on the TEPQdot. The influences of the laser field on the system are included by using the Ehlotzky approximation, and then Kramers-Henneberger transformation is carried out for the corresponding Schrödinger equation. The influences of the ponderomotive force on two-electron quantum dots embedded in plasmas are investigated. The behaviours, the similarities and the functionalities of the laser field, the plasma environment, and the quantum dot confinement are also scrutinized. In addition, the role of the plasma environments in the mentioned analysis is also discussed in detail. © 2018 Author(s).Öğe Screening effects on 12C+12C fusion reaction(Institute of Physics Publishing, 2018) Koyuncu F.; Soylu A.One of the important reactions for nucleosynthesis in the carbon burning phase in high-mass stars is the 12C+12C fusion reaction. In this study, we investigate the influences of the nuclear potentials and screening effect on astrophysically interesting 12C+12C fusion reaction observables at sub-barrier energies by using the microscopic ?-? double folding cluster (DFC) potential and the proximity potential. In order to model the screening effects on the experimental data, a more general exponential cosine screened Coulomb (MGECSC) potential including Debye and quantum plasma cases has been considered in the calculations for the 12C+12C fusion reaction. In the calculations of the reaction observables, the semi-classical Wentzel-Kramers-Brillouin (WKB) approach and coupled channel (CC) formalism have been used. Moreover, in order to investigate how the potentials between 12C nuclei produce molecular cluster states of 24Mg, the normalized resonant energy states of 24Mg cluster bands have been calculated for the DFC potential. By analyzing the results produced from the fusion of 12C+12C, it is found that taking into account the screening effects in terms of MGECSC is important for explaining the 12C+12C fusion data, and the microscopic DFC potential is better than the proximity potential in explaining the experimental data, also considering that clustering is dominant for the structure of the 24Mg nucleus. © 2018 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.Öğe The optimal ranges for the optical properties of two-electron quantum dot immersed in plasmas(Elsevier B.V., 2019) Bahar M.K.; Ungan F.; Soylu A.In this study, for the first time, the total refractive index changes (TRICs) and the total absorption coefficients (TACs) of the spherically confined two-electron parabolic quantum dot (TEPQD) embedded in the Debye and quantum plasmas generated by GaAs/GaAlAs heterostructure and modeled with the more general exponential cosine screened Coulomb (MGECSC) potential have been analyzed by solving the corresponding wave equation using the tridiagonal matrix method. Two different types of MGECSC potential have been used in the calculations. One of them is the most basic form of it obtained by adjusting the potential parameters for modeling the Debye plasma case, and other is the most common form of it in order to model the quantum plasma case. In addition to this, plasma environment is an important experimental argument in the synthesis and modification of quantum dots (QDs), the results of the screening effects on these and the fact that screening effect can be adjusted are the main motivation of considering the plasma environments in this study. In this context, the effects of external and structural parameters as well as plasma shielding parameters on TRICs and TACs of the TEPQD have been investigated in detail. The behavior of the external, structure and plasma shielding parameters on TEPQD's optical properties have been compared and the alternativeness to each other have been studied. It has also been shown how the external and structure parameters change the behaviors of the nonlinear optical properties on the Debye and quantum plasma environments. For the nonlinear optical properties of TEPQD, optimal ranges of all parameters, especially plasma shielding parameters, have been determined. It is clear that these detailed determinations will be very important in further theoretical investigations as well as the necessity for present and future experimental applications. © 2019 Elsevier B.V.Öğe Two-Electron Pseudodot System with Laser Effect in Plasmas(Institute of Electrical and Electronics Engineers Inc., 2019) Bahar M.K.; Soylu A.We have studied the two-electron pseudodot (TEPD) system immersed in plasma environments under the influence of a monochromatic linearly polarized laser field. The four different sets, constituted by the potential parameters, of the more general exponential cosine screened Coulomb potential are used to characterize the Debye and quantum plasma environments. The time dependent in the Schrödinger equation arising from the laser field is interchanged to the potential energy term from the kinetic energy term through the dipole approximation and the Kramers-Henneberger transformation. Then, the laser-dressed potential that denotes the effects of the laser radiation field is constituted by using the Ehlotzky approximation. In that case, as the analytical solution is impossible just now due to the complicated form of the Schrödinger equation, the numerical solution is carried out via the asymptotic iteration method. In this paper, the pseudodot system is considered because the quantum dots are very similar to atomic systems, and the pseudoharmonic potential is successful in explaining the atomistic structures. However, it is an important motivation for us that, as well as the importance of the laser-plasma interactions, the laser field is a considerable exciter for radiating, which exhibits remarkable confinement effects. Since, as well as the screening effects exhibited by plasmas on atomic systems, and their significant results, the plasma is a significant experimental argument in manufacturing and modification of the quantum dots, the plasma effects are taken into consideration in this paper. Within these motivations, all parameters that operate on the energies of TEPD system with the laser effect in plasmas are analyzed in detail, and the corresponding results are discussed thoroughly. © 1973-2012 IEEE.Öğe Two-electrons quantum dot in plasmas under the external fields(American Institute of Physics Inc., 2018) Bahar M.K.; Soylu A.In this study, for the first time, the combined effects of the external electric field, magnetic field, and confinement frequency on energies of two-electron parabolic quantum dots in Debye and quantum plasmas modeled by more general exponential cosine screened Coulomb (MGECSC) potential are investigated by numerically solving the Schrödinger equation using the asymptotic iteration method. The MGECSC potential includes four different potential forms when considering different sets of the parameters in potential. Since the plasma is an important experimental argument for quantum dots, the influence of plasmas modeled by the MGECSC potential on quantum dots is probed. The confinement frequency of quantum dots and the external fields created significant quantum restrictions on quantum dot. In this study, as well as discussion of the functionalities of the quantum restrictions for experimental applications, the parameters are also compared with each other in terms of influence and behaviour. In this manner, the motivation points of this study are summarized as follows: Which parameter can be alternative to which parameter, in terms of experimental applications? Which parameters exhibit similar behaviour? What is the role of plasmas on the corresponding behaviours? In the light of these research studies, it can be said that obtained results and performed discussions would be important in experimental and theoretical research related to plasma physics and/or quantum dots. © 2018 Author(s).Öğe Velocity dependent potential effects on two-electron quantum dot in plasmas(American Institute of Physics Inc., 2019) Bahar M.K.; Soylu A.In this study, for the first time, the effects of the velocity-dependent potential (VDP) on the energies of a two-electron parabolic quantum dot (TEPQD) in Debye and quantum plasma environments depicted by a more general exponential cosine screened Coulomb (MGECSC) potential are taken into consideration. The Schrödinger equation is modified by combining the MGECSC potential and VDP, solving numerically via the asymptotic iteration method. The Schrödinger equation with VDP is basically another type of one with position-dependent mass. The effects of VDP on two interacting electrons inside the parabolic quantum dot in plasmas are probed by considering the isotropic form factor with the harmonic (? (r) = ? 0 r 2) and constant (? (r) = ? 0) form. The alternativeness of the plasma shielding parameters to each other, the confinement parameter of the quantum dot, and the VDP parameters on energies and possible radiations of TEPQD are also discussed. © 2019 Author(s).
