Estimation of vertical migration velocity of Cs-137 in the Mount IDA/Kazdagi, Turkey

This paper presents the results obtained from a radioecological study carried out in the forest sites of Mount IDA (Kazdagi)/Edremit, Turkey. For 118 soil profiles, the depth distribution of Cs-137 activity was established by fitting the experimental points to an exponential, a gaussian or a log-normal function. The relaxation lengths were in the range of 1.09-16.7 cm with a mean of 5.73 cm, showing a slow transport and a strong retention capacity of Cs-137 even after the 26-y period of Chernobyl accident. From the data for the vertical distribution of Cs-137 in soil profiles, the mean annual migration velocity of Cs-137 was in the range of 0.11-0.62 cm year(-1) with a mean of 0.30 cm year(-1). Statistically significant correlations between the thickness of the humus layer and the mean annual velocity of Cs-137 were found for both coniferous and mixed forest sites. The mean annual velocity of Cs-137 in the forests sites with Pinus nigra var pallasiana was significantly higher than sites with Pinus brutia. External dose-rates from the Cs-137 in forest soils were estimated using a conversion factor used in many studies and comprised with the external dose-rates determined according to the vertical distribution of Cs-137 within the soil depth profiles. It is clearly seen that both levels and spatial distribution patterns of the external dose-rates from Cs-137 were influenced considerably with the vertical migration rate and the vertical distribution of Cs-137. (C) 2015 Elsevier Ltd. All rights reserved

A study on the extrinsic sensitivity and counting, efficiency of a gamma camera for a cylindrical source and a rectangular detector

In this work, the extrinsic counting efficiency and extrinsic sensitivity of a cylindrical source and a gamma camera with a rectangular detector were determined using homogeneous Tc-99(m). Scattered radiation effects were evaluated by both analyzing the energy spectrum of Tc-99m for the scatter fraction and plotting the extrinsic counting efficiency and sensitivity. It is found that the scattered fraction values increased with increasing source thickness. Calculated extrinsic sensitivity shows a gradually decreasing trend with increasing source thickness. The extrinsic efficiency decreases with increasing source thickness, It is concluded that increasing source to detector distances results with increasing extrinsic counting efficiency but decreasing extrinsic sensitivity

Persistence of Cs-137 in the litter layers of forest soil horizons of Mount IDA/Kazdagi, Turkey

WOS: 000347596000013PubMed ID: 25464048In 2010-2012, an extensive study was performed in forest sites of Mount IDA (Kazdagi)/Edremit 26 years after the Chernobyl accident. The Cs-137 activity concentrations were determined by gamma-ray spectrometry in the forest soil layers (O-L, O-F + O-H and A horizons) separately. Based on 341 surface soil samples and 118 soil profiles, activity concentrations of 137Cs in O-L horizons varied between 0.25 +/- 0.14 and 70 +/- 1 Bq kg(-1), while the ranges of Cs-137 activity concentrations in O-F + O-H and A horizons were 13 +/- 1-555 +/- 3 Bq kg(-1) and 2 +/- 1-253 +/- 2 Bq kg(-1), respectively. Cesium-137 deposition in the study area was estimated to be in the range of 1-39 kBq m(-2) and a linear relationship between the deposition of Cs-137 and the altitude was observed. The distributions of Cs-137 activities in O-L, O-F + O-H and A horizons throughout the region were mapped in detail. The highest Cs-137 activities were found in O-F + O-H horizons, with markedly lower Cs-137 activity in mineral horizons of soil profiles. It is observed that Cs-137 content of humus layer increases with the thickness of the humus layer for coniferous forest sites. The Cs-137 activity concentrations were higher than the recommended screening limits (150 Bq kg(-1)) at some of the investigated areas. The current activity concentration of top soil layers indicates that over many years since the initial deposition, Cs-137 activity is keeping still high in the organic horizons. (C) 2014 Elsevier Ltd. All rights reserved.Scientific and Technical Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [109Y336]Grateful thanks are offered to the provider of financial support for the research presented here: The Scientific and Technical Research Council of Turkey (TUBITAK) (Project no: 109Y336). The authors are also grateful to Prof. Dr. Gunseli Yaprak for professional advice on several aspects of the Gamma spectroscopy, to Mr. Nivazi Ozcankaya for his careful assistance in preparation of forest vegetation map of Kazdagi and to Mr. Huseyin Atay and Ms. Sabiha Vurmaz for assisting in sample collection, preparation of soils

Comparison of the Sleep Problems Among Adolescents Who Attempted Suicide and Healthy Adolescents

The aim of this study was to compare sleep problems among adolescents who attempted suicide and healthy adolescents who never attempted suicide. Adolescents who attempted suicide (study group, n = 103) and healthy adolescents (control group, n = 59) completed a questionnaire prepared by researchers including demographic factors. In addition, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) were administered to both groups. The median age was 16 years and 73% were girls, in both groups. The study group had lower rate of attending to school (88.3% vs. 100%; p = 0.001), academic achievement (45.7% vs. 83.1%; p = 0.001), higher rate of smoking (37.9% vs. 13.8%; p = 0.001), socializing problems (31.1% vs. 3.4%; p = 0.001), and appetite changes (57.3% vs. 39.7%; p = 0.032) than controls. The rate of those with PSQI scores 6 or higher was 53.4% in the attempted suicide group and 37.3% in the control group (p = 0.048). Adolescents, classified as sleepy according to the ESS, did not differ significantly between the groups (p = 0.214). Adolescents who attempted suicide had poor sleep quality. It is crucial to examine the kinds of sleep problems adolescents who have attempted suicide have experienced. Among adolescents attending outpatient clinics with poor sleep quality, PSQI can be a useful screening tool. Those with high scores should be evaluated for suicide risk

Quality of life and related factors among chronic hepatitis B-infected patients: a multi-center study, Turkey

balkan, ilker inanc/0000-0002-8977-5931; Altindis, Mustafa/0000-0003-0411-9669; Sahin, Ahmet Ziyaettin/0000-0003-1060-6746; atilla, aynur/0000-0001-8027-1991WOS: 000386954300001PubMed: 27809934Background: The aim of this study was to assess health-related quality of life (HRQOL) among chronic hepatitis B (CHB) patients in Turkey and to study related factors. Methods: This multicenter study was carried out between January 01 and April 15, 2015 in Turkey in 57 centers. Adults were enrolled and studied in three groups. Group 1: Inactive HBsAg carriers, Group 2: CHB patients receiving antiviral therapy, Group 3: CHB patients who were neither receiving antiviral therapy nor were inactive HBsAg carriers. Study data was collected by face-to-face interviews using a standardized questionnaire, Short Form-36 (SF-36) and Hepatitis B Quality of Life (HBQOL). Values equivalent to p < 0.05 in analyses were accepted as statistically significant. Results: Four thousand two hundred fifty-seven patients with CHB were included in the study. Two thousand five hundred fifty-nine (60.1 %) of the patients were males. Groups 1, 2 and 3, consisted of 1529 (35.9 %), 1721 (40.4 %) and 1007 (23.7 %) patients, respectively. The highest value of HRQOL was found in inactive HBsAg carriers. We found that total HBQOL score increased when antiviral treatment was used. However, HRQOL of CHB patients varied according to their socio-demographic properties. Regarding total HBQOL score, a higher significant level of HRQOL was determined in inactive HBV patients when matched controls with the associated factors were provided. Conclusions: The HRQOL score of CHB patients was higher than expected and it can be worsen when the disease becomes active. Use of an antiviral therapy can contribute to increasing HRQOL of patients