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Neuroscience & Medicine 2014年第4期5卷 177-182页

作者： Yildiz Degirmenci Ege Gulec Balbay ayhan ozturk Hulusi Kececi Mehmet Altan Neurology Department School of Medicine Duzce University Duzce Turkey Pulmonology Department School of Medicine Duzce University Duzce Turkey Neurology Department Mus State Hospital Mus Turkey

Approximately 20% of patients with sleep apnea will have headaches and 25% of patients with other sleep disorders will also experience headaches. We aim to evaluate sleep apnea related symptom prevalence in patient with headache presenting to neurology outpatient clinics. Twenty four patients with headache were asked for sleep apnea symptoms. The prevalence of snoring, excessive daytime sleepiness and witnessed apnea was 33.3%, 20.8% and 4.2%, respectively. Among sleep apnea symptoms, the presence of at least one symptom, at least two symptoms and all three symptoms were 9 (37.5%), 4 (16.7%) and 1 (4.2%), respectively. The frequency of major symptoms of sleep apnea syndrome was high in patient with nonspecific headache. In the light of literature review, in case of a suspicion of sleep disorder in a headache patient, it would be appropriate to question the major symptoms of OSAS, and to refer the patient to a polysomnographic evaluation for an objective diagnosis. This approach would be helpful to improve the quality of life of patients with headache.

关键词： Headache Obstructive Sleep Apne Syndrome Neurology Practice

Solutions in the Discrete Fractional Forms of Two Differential Equations with Singular Points

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 975-981页

作者： Okkes ozturk Independent Researcher Islahiye 27800Turkey

In present note,we apply the Leibniz formula with the nabla operator in discrete fractional calculus(DFC)due to obtain the discrete fractional solutions of a class of associated Bessel equations(ABEs)and a class of associated Legendre equations(ALEs),***,we exhibit a new solution method for such second order linear ordinary differential equations with singular points.

关键词： fractional calculus discrete fractional calculus discrete fractional solutions nabla operator

Solutions in the Discrete Fractional Forms of Two Differential Equations with Singular Points

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 638-644页

作者： Okkes ozturk 105th Street Apt&Islahiye 27800Turkey

关键词： fractional calculus discrete fractional calculus discrete fractional solutions Nabla operator

Effect of Magnetic Field on a p-Type δ-Doped GaAs Layer

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Chinese Physics Letters 2010年第7期27卷 233-236页

作者： E. ozturk Department of Physics Cumhuriyet University Sivas 58140 Turkey

The energy levels of holes in a p-type δ-doped GaAs structure under a magnetic field are theoretically calculated within the framework of the effective mass approximation for a uniform aceeptor distribution. The electronic structure is calculated by solving the Schrodinger and Poisson equations self-consistently. The effect of the magnetic field on the potential profile changes the degree of the confinement and localization, and thus this behavior can be used to study these systems in regions of interest, without the need to grow many different samples. It is found that the heavy-hole subbands contain many more energy states than the light-hole ones; the population of the heavy-hole levels represents approximately 91 % of all the carriers without magnetic field. With increasing magnetic field the total population of the heavy-holes increases and the number of filled states changes.

关键词： Magnetic field Energy Fields Computers Political systems

Nonlinear Optical Rectification, Second and Third Harmonic Generations in Square-Step and Graded-Step Quantum Wells under Intense Laser Field

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Chinese Physics Letters 2019年第6期36卷 93-97页

作者： O.ozturk E.ozturk S.Elagoz Department of Nanotechnology Engineering Cumhuriyet University Department of Physics Cumhuriyet University ASELSAN-Microelectronics Guidance & Electro-Optics

For square-step quantum wells(SSQWs) and graded-step quantum wells(GSQWs), the nonlinear optical rectification(NOR), second harmonic generation(SHG) and third harmonic generation(THG) coefficients under an intense laser field(ILF) are analyzed. The found results indicate that ILF can ensure a vital influence on the shape and height of the confined potential profile of both SSQWs and GSQWs, and alterations of the dipole moment matrix elements and the energy levels are adhered on the profile of the confined potential. According to the results, the potential profile and height of the GSQWs are affected more significantly by ILF intensity compared to SSQWs. These results indicate that NOR, SHG and THG coefficients of SSQWs and GSQWs may be calibrated in a preferred energy range and the magnitude of the resonance peak(RP) by tuning the ILF parameter. It is feasible to classify blue or red shifts in RP locations of NOR, SHG and THG coefficients by varying the ILF parameter. Our results can be useful in investigating new ways of manipulating the opto-electronic properties of semiconductor QW devices.

关键词： square-step quantum wells(SSQWs) graded-step quantum wells(GSQWs) nonlinear optical rectification(NOR)

Nickel accumulation and its effect on biomass,protein content and antioxidative enzymes in roots and leaves of watercress(Nasturtium officinale ***.)

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Journal of Environmental Sciences 2010年第4期22卷 526-532页

作者： Fatih Duman Fatma ozturk Faculty of Arts and Sciences Department of BiologyErciyes University

In order to understand its response towards nickel stress, watercress （Nasturtium officinale R. Br.） was exposed to nickel （1-25 mg/L） for 1, 3, 5 and 7 days. The accumulation and translocation of nickel were determined and the influence of nickel on biomass, protein content and enzymatic antioxidants was examined for both roots and leaves. It was determined that N. o fficinale could accumulate appreciable amounts of Ni in both roots and leaves. Nickel accumulated particularly in the roots of plants. Biomass increased at low nickel concentrations but certain measurable change was not found at high concentrations. Under stress conditions the antioxidant enzymes were up-regulated compared to control. An increase in protein content and enzyme activities was observed at moderate exposure conditions followed by a decline at both roots and leaves. The maximum enzyme activities were observed at different exposure conditions. Our results showed that N. officinale had the capacity to overcome nickel-induced stress especially at moderate nickel exposure. Therefore, N. officinale may be used as a phytoremediator in moderately polluted aquatic ecosystems.

关键词： nickel accumulation antioxidative enzymes biomass watercress

Earthquake hazard potential in the Eastern Anatolian Region of Turkey： seismotectonic b and Dc-values and precursory quiescence Z-value

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Frontiers of Earth Science 2018年第1期12卷 215-236页

作者： S. ozturk Gumushane University Department of Geophysics TR-29100 Gumushane Turkey

The Eastern Anatolian Region of Turkey is one of the most seismically and tectonically active regions due to the frequent occurrence of earthquakes. Thus, the main goal of this study is to analyze the regional and temporal characteristics of seismicity in the Eastern Anatolia in terms of the seismotectonic b-value, fractal dimension Dcvalue, precursory seismic quiescence Z-value, and their interrelationships. This study also seeks to obtain a reliable empirical relation between b and De-values and to evaluate the temporal changes of these parameters as they relate to the earthquake potential of the region. A more up-to-date relation of De = 2.55 -0.39＊b is found with a very strong negative correlation coefficient （r=- 0.95） by using the orthogonal regression method. The b-values less than 1.0 and the De-values greater than 2.2 are observed in the Northeast Anatolian Fault Zone, Askale, Erzurum, Igdlr and Caldlran Faults, Dogubeyazlt Fault Zone, around the Genc Fault, the western part of the Bitlis-Zagros Thrust Zone, Pulumir and Karakogan Faults, and the SancakUzunpmar Fault Zone. In addition, the regions having small b-values and large Z-values are calculated around the Geng, Piulumur and Karakogan Faults as well as the Saneak-Uzunpmar Fault Zone. Remarkably, the combinations of these seismotectonic parameters could reveal the earthquake hazard potential in the Eastern Anatolian Region of Turkey, thus creating an increased interest in these anomaly regions.

关键词： Eastern Anatolia b-value fractal dimension,precursory seismic quiescence earthquake hazard

MOTIONS OF CURVES IN THE GALILEAN SPACE G_3

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Acta Mathematica Scientia 2015年第5期35卷 1046-1054页

作者： Ufuk ozturk Suleyman CENGIZ Esra Betul KOC ozturk Department of Mathematics Faculty of Science ank?r? Karatekin University

In this article, we study the flows of curves in the Galilean 3-space and its equiform geometry without any constraints. We find that the Frenet equations and the intrinsic quantities of the inelastic flows of curves are independent of time. We show that the motion of curves in the Galilean 3-space and its equiform geometry are described by the inviscid and viscous Burgers＇ equations.

关键词： Galilean geometry equiform geometry motions of curves inextensible flows Burgers' equation Frenet frames

Electronic Properties of p-Type δ-Doped GaAs Structure under Electric Field

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Chinese Physics Letters 2008年第4期25卷 1415-1418页

作者： Emine ozturk Ismail SOKMEN Department of Physics Cumhuriyet University 58140 SIVAS Turkey Department of Physics Dokuzeylul University IZMIR Turkey

We theoretically investigate the electronic properties of p-type δ-doped GaAs inserted into a quantum well under the electric field, at T = 0 K. We will investigate the influence of the electric field on the δ-doping concentration for a uniform distribution. The depth of confining potential, the density profile, the Fermi level, the subband energies and the subband populations calculate by solving the Schrodinger and Poisson equations self consistently. It is found that the changes of the electronic properties are quite sensitive to the applied electric field and the doping concentration. As different from single n-type δ-doped structure, we see a replace between the ground light-hole （lh1 ） subband and the first excited heavy-hole （hh2） subband whenever the external electric field reaches a critical value. We find the abrupt changing of the subband energies and the subband populations whenever the applied electric field reaches a certain value. Also, it is found that the heavy-hole subbands contain many more energy states than the light-hole ones, the population of the heavy-hole levels represent approximately 91% of all the carriers.

关键词： supernova explosion proto-neutron star shock wave

Nonlinear Intersubband Transitions in Square and Graded Quantum Wells Modulated by Intense Laser Field

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Chinese Physics Letters 2014年第12期31卷 95-98页

作者： Emine ozturk Ismail Sokmen Department of Physics Cumhuriyet University Sivas 58140 Turkey Department of Physics Dokuz Eylfil University Izmir 35160 Turkey

There has been increasing interest, both exper- imentally and theoretically, in the investigation of low-dimensional semiconductor heterostructures due to their intrinsic physical properties and technological applications in electronic and optoelectronic devices. The studies on quantum heterostructures have opened a new field in fundamental physics, and also offer a wide range of potential applications for optoelectronic devices. By varying the profile of a semiconductor quantum well （QW）, both the subband state energies and their wave functions change, and so do various physical properties depending on them.

关键词： Nonlinear Intersubband Square and Graded Quantum Intense Laser Field