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In this article we obtain asymptotic formulas of arbitrary order for eigenfunctions and eigenvalues of the nonselfadjoint Sturm-Liouville operators with Dirichlet boundary conditions, when the potential is a summable function. Then using these we compute the main part of the eigenvalues in special cases.

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Abstract  

Calibration standardization of X-ray fluorescence method was carried out for the determination of the anorganic contents in diuretic herbs as calledFolia Betulae, Stylus Maydis, Flores Verbasci, Equisetum Arvense andFlos Helichrysi, growing in Turkey. These herbs are widely used in pharmacy and public health for kidney disease theraphy. Herb samples were steeped in the water and mixed through the pure cellulose, then pelletized in the intermediate thickness. An annular source of109Cd (3.7 MBq) was used for excitation of fluorescent K lines of elements lying between potassium and zirconium. Toxic elements in considerable amounts were not found.

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Ant responses were tested under both the natural geomagnetic and artificially induced Earth-strength electromagnetic field. Foragers were trained for a month to visit a food source at the north arm accessed through an orientation platform assembly. Under the natural geomagnetic field, when all other orientational cues were eliminated, results indicated significant heterogeneity of ant distribution with the majority seeking geomagnetic north in darkness. However, in light, foragers failed to discriminate geomagnetic north. Under shifted artificial electromagnetic field, orientation was predominantly on the artificial magnetic N/S axis with a significant preference for the artificial north in both light and dark conditions.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: B. Karakelle, N. Öztürk, A. Köse, A. Varinlioğbrevelu, A. Erkol, and F. Yilmaz

Abstract  

The city of Kocaeli is in the western part of Anatolia in Turkey and has a population of approximately 1.000.000. There is no information about radioactivity in the Kocaeli soils samples so far. For this reason, the concentrations of the natural radionuclides in soil samples from 27 different sampling stations in Kocaeli Basin and its surroundings have been determined. The results have been compared with other radioactivity measurements in different country"s soils. The typical concentrations of 137Cs, 238U, 40K, 226Ra, 232Th found in surface soil samples ranged from 2±0.6 to 25±6 Bq/kg, from 11±4 to 49±10 Bq/kg, from 161±30 to 964±127 Bq/kg, from 10±4 to 58±11 Bq/kg, and from 11±3 to 65±13 Bq/kg, respectively.

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Acta Veterinaria Hungarica
Authors: A. Dayi, C. S. Bediz, B. Musal, O. Yilmaz, A. Comlekci, M. Celiloglu, and D. Cimrin

Leptin is mainly synthesised in white adipose tissue. Besides its effects on body weight and metabolic homeostasis, leptin also has effects on puberty, sexual maturation and reproduction. In this study the relationship between leptin, IGF-1, oestradiol (E2) and progesterone levels were investigated in serum and follicular fluid from cows. This study included 72 healthy, Brown Swiss cows aged 4-5 years. Samples from the jugular vein and follicular fluids were collected. Phases of the oestrus cycle of cows were classified according to their serum progesterone levels (< 3.18 nmol/l, follicular phase and the others as luteal phase). Follicles were grouped as large (= 8 mm) or small (< 8 mm). Leptin, IGF-1, oestradiol and progesterone levels were measured from serum and follicular fluid. Leptin concentrations were found to be significantly higher in luteal-phase follicular fluid of small follicles (P < 0.05). These were classified as atretic follicles. There was a positive correlation between serum and follicular fluid leptin levels in the luteal phase. Serum leptin was found to have a positive correlation with follicular fluid progesterone level (P = 0.01) in the preovulatory follicles. The present study shows that there is a relationship between the concentration of leptin in follicular fluid and atresia in small follicles.

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Acta Physiologica Hungarica
Authors: Enver Ozan, A. Kükner, L. Canpolat, H. Öner, M.R. Gezen, S. Yilmaz, and S. Ozan

In this study, rats were made to inhale cigarette smoke in a specifically prepared container for different periods. The lung tissue samples of the subjects were examined by light microscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Malonaldehyde, one of the free oxygen radicals was determined in lungs and plasma. The catalase activity level of erythrocyte and arginase levels were determined. Three groups were formed. The rats in the Ist and IInd groups were made to inhale cigarette smoke for 30 and 60 minutes a day for a total period of 3 months. Control group, the rats in the IIIrd group (controls) were made to inhale clean air during the same periods. An increase in the number of macrophages was observed in the pulmonary tissue of the exposed groups. Especially in the group that inhaled the smoke for long periods, the number of macrophages and the inclusion bodies contained in them increased. These differences could easily be observed in TEM studies. In the light microscopy and SEM observations, it arouse attention that the alveolar macrophages occurred as sets and their activation increased. Depending on the length of the exposure to cigarette smoke, an increase in the number of macrophages was observed. Statistically significant increases were determined in the malonaldehyde levels of pulmonary tissue and plasma when compared to the control group. Besides significant increases were found in the catalase activity levels of erythrocytes in the experimental groups.

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Acta Physiologica Hungarica
Authors: F. Salman, G. Erten, M. Unal, B. Kiran, S. Salman, G. Deniz, M. Yilmaz, A. Kayserilioglu, and N. Dinccag

The essential therapy of diabetes mellitus includes medical nutrition therapy (MNT), exercise and medical therapy. Exercise, besides its metabolic effects, has positive influence on the immune system, but some forms of exercise may cause trauma for muscle and skeletal systems, they may also support negative effects on the immune system. Nineteen type 1 diabetic patients (mean age 22.1±2.8 yrs), followed by Diabetes Outpatient Clinic and twenty age matched male control subjects were included into the study, to demonstrate the effects of maximal, acute exercise on the immune system. The exercise test was performed according to Bruce protocol on treadmill. In diabetic subjects, increased CD19 and CD23 expressions were observed before exercise. In both groups (diabetic/control) CD3, CD4 expressions and CD4/CD8 ratio were decreased following the exercise, however expression of natural killer (NK) cells increased. Compared to type 1 diabetic patients healthy subjects had longer acute exercise that caused the increased level of CD8 expression, however type 1 diabetic patients did not show any difference. These results indicate that submaximal aerobic exercise might be recommended for type 1 diabetics without any complications because of its positive reflection on metabolic control and no negative effects on the immune system.

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