Measurement of melatonin in body fluids: Standards, protocols and procedures

Abstract: The circadian rhythm of melatonin in saliva or plasma, or of the melatonin metabolite 6‐ sulphatoxymelatonin in urine, is a defining feature of suprachiasmatic nucleus function, the endogenous oscillatory pacemaker. These measurements are useful to evaluate problems related to the onset or offset of sleep and for assessing phase delays or advances of rhythms in entrained individuals. Additionally, they have become an important tool for psychiatric diagnosis, its use being recommended for phase typing in patients suffering from sleep and mood disorders. Thus, the development of sensitive and selective methods for the precise detection of melatonin in tissues and fluids of animals emerges as necessary. Due to its low concentration and the co‐existence of many other endogenous compounds in blood, the determination of melatonin has been an analytical challenge. This review discusses current methodologies employed for detection and quantification of melatonin in biological fluids and tissues

Distribution of radiocesium and natural gamma emitters in pine needles in coniferious forest sites of Izmir

WOS: 000251536900011PubMed ID: 17512205pine needles. Activity concentrations of the concerned radionuclides in the needle samples were as follows: Be-7, 24.6 +/- 2.40 to 210 +/- 7.21 Bq kg(-1), K-40, 23.5 +/- 12.4 to 287 +/- 15.6 Bq kg(-1), Ra-226, 0.44 +/- 0.12 to 12.3 +/- 2.18 Bq kg(-1), and (CS)-C-137, 0.61 +/- 0.30 to 2.29 +/- 0.38 Bq kg(-1). It is found that the frequency distributions obtained for Be-7 and (CS)-C-137 can be fitted to a normal distribution, and for K-40 and Ra-226 can be fitted to a log-normal distribution. (c) 2007 Elsevier Ltd. All rights reserved

137Cs, 40K, alkali-alkaline earth element and heavy metal concentrations in wild mushrooms from Turkey

In 2002, an extensive study was performed in forest sites of Izmir. This first study results led on the one hand, to quantify of 137Cs and 40K concentration in mushrooms collected in the Izmir region and to a first evaluation of dose in people due to the ingestion of radionuclide- contaminated mushrooms. The mushroom concentration values varied over a wide range from below detection limit to 401 ± 4Bq kg-1 (dry wt) for 137Cs. The 40K concentration values obtained for different species of mushrooms rang ed from 588 ± 26 Bq kg-1 to 2024 ± 63 Bq kg-1 (dry wt). The annual effective dose values due to mushroom ingestion for 137Cs are lower than the ICRP-2007's reference level value of 1 mSv for "existing" exposure situation. Inductively coupled plasma-mass spectrometry was used to measure many alkali-alkaline earth elements and heavy metals in mushroom samples. The relationships among the concentrations of 137Cs and the stable elements were presented and the occurrence of metals in mushrooms was evaluated. © Akadémiai Kiadó, Budapest, Hungary 2010.Firat University Scientific Research Projects Management Unit: 2003 NBE 006 Ege ÜniversitesiAcknowledgment Grateful thanks are offered to the provider of financial support for the research presented here: Ege University Scientific Research Project (Project no: 2003 NBE 006). The authors also would like to thank Mr. Halil Solak (Mug^la University, Ula Technical High School, Department of Mycology) for his indispensable help during precise identification of the different fungi species and the ACME Laboratory for carrying out trace element analyses of mushroom samples. -

Soil-to-mushroom transfer of 137Cs, 40K, alkali-alkaline earth element and heavy metal in forest sites of Izmir, Turkey

The present work is devoted to an investigation on the soil to mushroom transfer parameters for 137Cs and 40K radionuclides, as well as for some stable elements and heavy metals. The results of transfer factors for 137Cs and 40K were within the range of 0.06-3.15 and 0.67-5.68, respectively and the most efficiently transferred radionuclide was 40K. The TF values for 137Cs typically conformed to a lognormal distribution, while for 40K showed normal distribution. Statistically significant correlations between 137Cs soil to mushroom transfer factors and agrochemical soil properties have been revealed. Although the concentration ratios varied within the species, the most efficiently transferred elements seems to have been K, followed by Rb, Zn, Cu, Cd, S, Cs and Hg. © 2010 Akadémiai Kiadó, Budapest, Hungary

Wp?yw wody morskiej na w?a?ciwo?ci betonu z dodatkiem py?u krzemionkowego

[No abstract available

Structural Breaks, Tourism and Co2 Emissions: The case of Turkey

Turkey is a growing economy with high CO2 emissions and preferred tourist destinations in the world. Therefore, the study deals with the tourism-CO2 emissions link over the period 1983-2017 in case of Turkey by integrating renewable energy consumption to the CO2 emissions specification as an additional variable. The stationarity analysis of the variables is examined by Ng-Perron and Vogelsang-Perron tests. The ARDL and Hatemi-J cointegration approaches are employed to determine the existence of cointegration among the variables under structural breaks while the causality analysis is carried out through the VECM procedure. There exists cointegration among the variables under structural breaks. There also exists evidence in favour of EKC hypothesis. The DOLS, FMOLS and CCR results reveal that tourism and renewable energy consumption decrease CO2 emissions in the long run. Additionally, a long-run bi-directional causality between tourism, renewable energy, and CO2 emissions exists. The empirical results obtained from the study can provide several policy suggestions to reduce environmental pollution for Turkish economy

A radiological survey of the Egrigöz granitoid, Western Anatolia/Turkey

PubMed ID: 25979749A radiological survey of the granitoid areas throughout Western Anatolia was conducted during 2007-14. As a part of this radiological survey, this article presents results obtained from Egrigöz pluton, which lies in the northeastern region of Western Anatolia. In the investigated area, the activity measurements of the natural gamma-emitting radionuclides (226Ra, 232Th and 40K) in the granitic rock samples and soils have been carried out by means of the NaI(Tl) gamma-ray spectrometry system. The activity concentrations of the relevant natural radionuclides in the granite samples appeared in the ranges as follows: 226Ra, 28-95 Bq kg-1; 232Th, 50-122 Bq kg-1 and 40K, 782-1365 Bq kg-1, while the typical ranges of the 226Ra, 232Th and 40K activities in the soil samples were found to be 7-184, 11-174 and 149-1622 Bq kg-1, respectively. Based on the available data, the radiation hazard parameters associated with the surveyed rocks/soils are calculated. The corresponding absorbed dose rates in air from all those radionuclides were always much lower than 200 nGy h-1 and did not exceed the typical range of worldwide average values noted in the UNSCEAR (2000) report. Furthermore, the data are also used for the mapping of the surface soil activity of natural radionuclides and the corresponding gamma dose rates of the surveyed area. © The Author 2015. Published by Oxford University Press. All rights reserved

Estimating the properties of ground-waste-brick mortars using DNN and ANN

Demir, Ilhami/0000-0002-8230-4053WOS: 000456418500009In this study, deep-neural-network (DNN)- and artificial-neural-network (ANN)- based models along with regression models have been developed to estimate the pressure, bending and elongation values of ground-brick (GB)-added mortar samples. This study is aimed at utilizing GB as a mineral additive in concrete in the ratios 0.0%, 2.5%, 5.0%, 7.5%, 10.0%, 12.5% and 15.0%. In this study, 756 mortar samples were produced for 84 different series and were cured in tap water (W), 5% sodium sulphate solution (SS5) and 5% ammonium nitrate solution (AN5) for 7 days, 28 days, 90 days and 180 days. The developed DNN models have three inputs and two hidden layers with 20 neurons and one output, whereas the ANN models have three inputs, one output and one hidden layer with 15 neurons. Twenty-five previously obtained experimental sample datasets were used to train these developed models and to generate the regression equation. Fifty-nine non-training-attributed datasets were used to test the models. When these test values were attributed to the trained DNN, ANN and regression models, the brick-dust pressure as well as the bending and elongation values have been observed to be very close to the experimental values. Although only a small fraction (30%) of the experimental data were used for training, both the models performed the estimation process at a level that was in accordance with the opinions of experts. The fact that this success has been achieved using very little training data shows that the models have been appropriately designed. In addition, the DNN models exhibited better performance as compared with that exhibited by the ANN models. The regression model is a model whose performance is worst and unacceptable; further, the prediction error is observed to be considerably high. In conclusion, ANN- and DNN-based models are practical and effective to estimate these values