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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

Corneal properties in children with congenital isolated growth hormone deficiency

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International Journal of Ophthalmology(English edition) 2014年第2期7卷 317-320页

作者： Pinar Nalcacioglu-Yuksekkaya Emine Sen ufuk Elgin Mumin Hocaoglu Faruk ozturk Sebahat Agladioglu Yilmaz Havva Nur Kendirci Semra etinkaya Zehra Aycan Department of Pediatric Ophthalmology Dr Sami Ulus Children's Health and Disease Training and Research Hospital Ulucanlar Eye Research Hospital Department of Pediatric Endocrinology Dr Sami Ulus Children's Health and Disease Training and Research Hospital

AIM:To compare the corneal parameters of children with congenital isolated growth hormone deficiency and healthy ***:In this cross-sectional,prospective study,50 cases with growth hormone(GH)deficiency treated with recombinant GH and 71 healthy children underwent a complete ophthalmic *** corneal hysteresis(CH),corneal resistance factor(CRF),Goldmann-correlated intraocular pressure(IOPg)and corneal-compensated intraocular pressure(IOPcc)were measured with the Ocular Response Analyzer(ORA).Central corneal thickness(CCT)was measured by a ultrasonic ***:The mean age was 13.0±3.0 years in the GH deficiency group consisting of 21 females and 29 males and 13.4±2.4 years in the healthy children group consisting of 41 females and 30 *** was no statistically significant difference between the groups for gender or age(Chi-square test,P=0.09;independent ttest,P=0.28,respectively).The mean duration of recombinant GH therapy was 3.8±2.4y in the study *** mean CH,CRF,IOPg and IOPcc values were 11.0±2.0,10.9±1.9,15.1±3.3,and 15.1±3.2 mm Hg respectively in the study *** same values were 10.7±1.7,10.5±1.7,15.2±3.3,and 15.3±3.4 mm Hg respectively in the control *** mean CCT values were 555.7±40.6,545.1±32.5μm in the study and control groups *** was no statistically significant difference between the two groups for CH,CRF,IOPg,IOPcc measurements or CCT values(independent t-test,P=0.315,0.286,0.145,0.747,0.13 respectively).CONCLUSION:Our study suggests that GH deficiency does not have an effect on the corneal parameters and CCT *** observation could be because of the duration between the beginning of disease and the diagnosis and beginning of GH therapy.

关键词： child corneal biomechanical parameters central corneal thickness growth hormone deficiency

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

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

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

Interaction of L-Arginine-methyl ester and Sonic hedgehog in liver ischemia-reperfusion injury in the rats

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World Journal of Gastroenterology 2007年第28期13卷 3841-3846页

作者： Mehmet Cudi Tuncer Hayrettin ozturk Huseyin Buyukbayram Hulya ozturk Dicle University Medical SchoolDepartments of AnatomyDiyarbakirTurkey Abanty Izzet Baysal University Medical SchoolDepartments of Pediatric SurgeryBoluTurkey Dicle University Medical SchoolDepartments of PathologyDiyarbakirTurkey Izzet Baysal Obstetric and Children Hospital Department of Pediatric SurgeryBoluTurkey

AIM： To investigate the role of Sonic hedgehog （Shh） on the course of liver ischemia and reperfusion （I/R） in rats, and the interaction between treatment with nitric oxide donor L-Arginine-methyl ester （L-Arg） and up-regulation of Shh expression.METHODS： A total of 30 male Sprague-Dawley rats weighing 220-240 g were used in this study. Shamcontrol group （G1, n = 10）： a sham operation was performed （except for liver I/R）. I/R-untreated group （G2, n = 10）： rats underwent liver ischemia for 1 h followed by reperfusion for 45 min. I/R-L-Arg group （G3, n = 10）： after performing the same surgical procedure as in group 2, animals were treated with L-Arg. Liver tissues were taken for determination of malondialdehyde （MDA） levels, and biochemical and histological evaluations were made.RESULTS： Plasma alanine aminotransferase （ALT）, aspartate aminotransferase （AS-T）, lactate dehydrogenase （LDH） and T-glutamyltranspeptidase （GGT） activities were higher in group 2 than in group 3. MDA values and the hepatic injury score decreased in the L-Arg treated group compared to the I/R-untreated group. In group 2, the hepatoo/tes were swollen with marked vacuolization. Group 3 rats showed well-preserved liver parenchyma, with hepatocytes extending from the central vein. The morphology of the hepatocytes and the sinusoidal structures was normal, without any signs of congestion. Mild Shh positive immunostaining was detected in group 2 animals. The expression of immunoreactive cells was increased markedly in liver tissue from I/R-L-Arg rats.CONCLUSION： Our findings suggest that Shh molecules are critical factors in the pathophysiology of inflammatory liver injury induced by I/R. In addition, NO plays an important role in the immunohistochemical expression of these molecules.

关键词： Ischemia/reperfusion Liver Sonic hedgehog L-Arginine-methyl ester

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World Journal of Gastroenterology 2006年第33期12卷 5379-5383页

作者： Halil Eken Hayrettin ozturk Hulya ozturk Huseyin Buyukbayram Mardin Children Hospital Department of Pediatric Surgery Diyarbakir Turkey Abanty Izzet Baysal University Medical School Departments of Pediatric Surgery Bolu Turkey Diyarbakir Children Hospital Department of Pediatric Surgery Diyarbakir Turkey Dicle University Medical School Departments of Pathology Diyarbakir Turkey

AIM: To evaluate the effects of dexamethasone on liver damage in rats with bile duct ligation. METHODS: A total of 40 male Sprague-Dawley rats, weighing 165-205 g, were used in this study. Group 1 (sham-control, n = 10) rats underwent laparotomy alone and the bile duct was just dissected from the surrounding tissue. Group 2 rats (untreated, n = 10) were subjected to bile duct ligation (BDL) and no drug was applied. Group 3 rats (low-dose dexa, n = 10) received a daily dose of dexamethasone by orogastric tube for 14 d after BDL. Group 4 rats (high-dose dexa, n = 10) received a daily dose of dexamethasone by orogastric tube for 14 d after BDL. At the end of the two-week period, biochemical and histological evaluations were processed. RESULTS: The mean serum bilirubin and liver enzyme levels signifi cantly decreased, and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) values were significantly increased in low-dose dexa and high-dose dexa groups when compared to the untreated group. The histopathological score was significantly less in the low-dose and high-dose dexa groups compared to the untreated rats. In the low-dose dexa group, moderate liver damage was seen, while mild liver damage was observed in the high-dose dexa group. CONCLUSION: Corticosteroids reduced liver damage produced by bile duct obstruction. However, the histopathological score was not signifi cantly lower in the high-dose corticosteroid group as compared to the low-dose group. Thus, low-dose corticosteroid provides asignifi cant reduction of liver damage without increased side effects, while high dose is associated not with lower fi brosis but with increased side effects.

关键词： Bile duct ligation Hepatic fibrosis Dexamethasone