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Abstract  

NAA has been applied to determine the concentration of K, As, Se, Zn, Cr, Cs, Fe, Co, Sb, Ni and Ca in sediments and a macroalgae species collected from the Küçükçekmece Lagoon and Marmara Sea. The lagoon sediment showed higher metal levels than the sea sediment. The metal contents in algae species are not changed significantly between months and sampling sites except Zn and Cr. The profile of the lagoon sediments was also investigated.

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Abstract  

Cesium-137 concentrations in red, brown and green algae have been studied for the calculation of natural depuration rates. The algae species were collected from the same population of the Black Sea stations during the period of 1986–1995. The natural depuration rates are estimated as biological half-lives. The pattern of depuration results represented by a single component for each algae division. The biological half-lives of137Cs in red (Phyllophora nervosa), green (Chaetomorpha linum) and brown (Cystoceira barbata) algae are estimated to be 18.5, 21.6 and 29.3 months, respectively.137Cs and40K activity levels and their ratios in algae species in two stations in Black Sea region of Turkey have been determined during the period of 1990–1995. The results showed that the Sinop region was more contaminated than the ile region on the Black Sea coast of Turkey from the Chernobyl accident.

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Abstract  

During the periods of 1997–1998, macroalgae, sea snail, mussel, fish and sediment samples were collected from different stations at Turkish Black Sea coast in order to determine activity levels of 137Cs radionuclide. 137Cs activity in the tested algae species and in soft parts of mussel and sea snail, were found to be below the lower limit of detection. On the other hand, the 137Cs concentration in muscle tissue of the sea snail samples were found from 6±2 to 19±7 Bq·kg–1 dry weight. The range of the 137Cs concentration in anchovy fish muscles were found between 4±2 – 10±5 Bq·kg–1 dry weight. The 137Cs concentration in the whiting fish muscle was found below the lower limit of detection. However, this activity found in shad fish muscle to be 25±10 Bq·kg–1 dry weight. The concentrationsof the 137Cs activity in the sediment samples proved that the eastern region of the Black Sea was affected by Chernobyl at a very high degree compared with the western part. The measured 238U, 232Th and 40K concentrations in sediment samples are within the range of the cited values in the previous works at the Turkish Black Sea coast.

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Acta Physiologica Hungarica
Authors:
E. Nurullahoğlu-Atalık
,
N. Okudan
,
M. Belviranlı
,
H. Esen
,
Y. Yener
, and
Y. Öznurlu

Acrylamide (ACR) is a chemical used in many industries around the world and was found to form naturally in foods cooked at high temperatures. The aim of the present study is to evaluate the influence of ACR treatment on vascular responses to phenylephrine (PHE; 10−9-3×10−4 M) and potassium chloride (KCl; 5–100 mM). We also examined the role of gender in these responses. The animals in both genders were divided into three groups as follows. (1) Control animals, (2) ACR-I; ACR-treated (2 mg/kg-d for 90 days), (3) ACR-II; ACR-treated (5 mg/kg-d for 90 days). Male rat aortas were more sensitive to PHE and KCl than female aortas. ACR-treatment increased the sensitivity to PHE and KCl, in both genders. Compared to the control group, ACR treatment significantly reduced the luminal area of both male and female rat aortas. Furthermore, the responses to PHE and KCl were similar in both 2 mg/kg-d ACR-treated rat aortas with 5 mg/kg-d ACR-treated rat aortas, in both genders. The results of this study suggest that ACR treatment affects vascular contractility and morphology in both gender of rat aorta.

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