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Isotopes in Environmental and Health Studies

Mika Hayashi, Maximo Larry Lopez Caceres, Yoshihiro Nobori, Byambasuren Mijidsuren, Jens Boy
In the last decades a drastic increase in air temperature but a stable precipitation regime in Mongolia has led to gradual drying conditions. Thus, we evaluated the effect of spatial and climatic characteristics on the soil-plant nitrogen dynamics in three representative larch stands (Larix sibirica) with different geographical and climatic conditions using stable nitrogen isotopes. The results showed significant differences in the soil inorganic N content among sites and consequently a different isotopic composition in the plant-soil system...
August 29, 2018: Isotopes in Environmental and Health Studies
Heike Wanke, Marcel Gaj, Matthias Beyer, Paul Koeniger, Josefina T Hamutoko
The study area is the Namibian part of the Cuvelai-Etosha Basin (CEB), located in central northern Namibia. The CEB is home to 40 % of Namibia's population, and most of the people live in rural areas. These people depend on both surface and groundwater resources which are limited in this dryland (mean annual rainfall ranging from 250 to 550 mm/a). The isotopic signatures of δ18 O and δ2 H from water samples (n = 61) collected over a course of 9 years from various research projects and existing (but mainly unpublished) data of meteoric water of the CEB (10 sites) were evaluated and local meteoric water lines (LMWLs) developed...
August 6, 2018: Isotopes in Environmental and Health Studies
Gerhard Strauch
No abstract text is available yet for this article.
October 2018: Isotopes in Environmental and Health Studies
Andrius Garbaras, Justina Šapolaitė, Inga Garbarienė, Žilvinas Ežerinskis, Agnė Mašalaitė-Nalivaikė, Raminta Skipitytė, Artūras Plukis, Vidmantas Remeikis
In the present study, a combination of the stable carbon isotope ratio (13 C/12 C) with radiocarbon data (14 C) allowed us to perform the aerosol source apportionment. Filter samples of PM1 were collected during the warm and cold periods in rural and urban sites in Lithuania. The 14 C/12 C ratio of total carbon (TC) was measured using the single stage accelerator mass spectrometer quantifying of fossil and non-fossil derived aerosol emissions. The δ13 C value was measured using an elemental analyser interfaced with an isotope ratio mass spectrometer...
October 2018: Isotopes in Environmental and Health Studies
Carmen Grisel Méndez-García, Elizabeth Teresita Romero-Guzmán, Héctor Hernández-Mendoza, Corina Solís Rosales, Efraín Rafael Chávez Lomelí
The monitoring and evaluation of radioactive content in samples of PM10 aerosols have been investigated. The specific radioactivity concentrations (SRC) of 234 U, 235 U, 238 U and 232 Th were determined using inductively coupled plasma-sector field mass spectrometry in 13 samples collected in Mexico City and 8 samples collected in Cuernavaca in the centre of Mexico. The SRC of the radioisotopes analysed in PM10 were larger than those reported in PM2.5 . The enrichment factor was greater than 5, indicating anthropogenic influences in both sites...
October 2018: Isotopes in Environmental and Health Studies
Małgorzata Pająk, Marianna Kańska
To investigate isotope effects in the hydroxylation of [3',5'-2 H2 ]-α-methyl- and [3',5'-2 H2 ]-N-methyl-l-tyrosine, they were synthesised using acid catalysed isotope exchange at high temperature. The kinetic and solvent deuterium isotope effects on Vmax and Vmax /Km parameters of tyrosinase in its action on methylated derivatives of l-tyrosine were determined using the non-competitive spectrophotometric method. Lineweaver-Burk plots were used to consider the inhibition type of O-methyl-l-tyrosine, revealing that it is an uncompetitive inhibitor of tyrosinase...
October 2018: Isotopes in Environmental and Health Studies
Maximo Larry Lopez Caceres, Sayako Nakano, Juan Pedro Ferrio, Mika Hayashi, Takeshi Nakatsuka, Masaki Sano, Toshiro Yamanaka, Yoshihiro Nobori
The March 2011 Mega-Tsunami in eastern Japan damaged at different degrees the black pine (Pinus thunbergii) forests along the coast. In order to evaluate the recovery of black pine four years later, tree-ring samples from 9 trees for the period 2002-2014 were analyzed for ring growth and stable isotopes (δ13 C, δ15 N and δ18 O). The results showed that annual tree-ring width decreased approximately 70 % from the year 2011 to 2014 compared to the period previous to the tsunami (2002-2010). The multiple isotopic analyses showed that the reduction in growth was caused by soil salinity that prompted stomatal closure and an abrupt increase of tree-ring δ13 C...
October 2018: Isotopes in Environmental and Health Studies
Libin Wu, Liqiang Xu, Shengjie Hou, Xueying Wang, Pingqing Fu, Xiaodong Liu
We analyzed 13 C characteristics in samples of bird bones, feathers, eggshell carbonate and membrane from modern specimens of red-footed booby (Sula sula) as well as fish muscle, scales, and bones from its predominant food source, flying fish (Exocoetus volitans), and muscle from its secondary food source squid (Loligo chinensis), as well as in ancient sub-fossil samples of seabird and flying fish at the Xisha Islands, South China Sea. δ13 C is tissue-specific in both seabirds and flying fish due to the variance in turn-over among the tissues and differences in the type and content of amino acids across a diverse range of tissues...
October 2018: Isotopes in Environmental and Health Studies
Wael M Badawy, Octavian G Duliu, Marina V Frontasyeva, Hussein El Samman, Arnaud Faanhof
The activity concentrations of natural 40 K, 232 Th, and 238 U in 89 soil and 84 sediment samples collected over the entire Egyptian Nile River basin including the Nile delta are reported based on the results of epithermal neutron activation analysis. The average activity concentrations of 40 K, 232 Th, and 238 U equal to 15.3 ± 6.6, 15.6 ± 11.1 and 220 ± 31 Bq/kg, respectively, are significantly lower than those reported for the Upper Continental Crust, World Average Sediments as well as World Average Soils, suggesting the presence of a considerable portion of mafic material, most probably originating from the Ethiopian High Plateau...
October 2018: Isotopes in Environmental and Health Studies
Habu Tela Abba, Wan Muhamad Saridan Wan Hassan, Muneer Aziz Saleh, Abubakar Sadiq Aliyu, Ahmad Termizi Ramli, Hassan Abdulsalam
The Jos Plateau has been reported to have elevated levels of natural background radiation. A few earlier studies have measured the levels of natural radioactivity for specific locations in the area. Our interest is to investigate how geology of the study area influences the activity concentrations of natural radionuclides. Thus, the activity concentrations of terrestrial radionuclides in soil samples collected across the geological formations of the Jos Plateau were determined by gamma spectrometry technique...
October 2018: Isotopes in Environmental and Health Studies
Vasily A Vavilin, Sergey V Rytov, Lyudmila Y Lokshina
We described mathematically the process of peat methanization in a boreal mesotrophic fen. Gaseous and dissolved CH4 and CO2 as well as their δ13 C signatures were considered in the dynamic equations for incubation bottles. In accordance with the model, acetate, H2 , and CO2 were produced during cellulose hydrolysis and acidogenesis. 13 C/12 C in CO2 was a key variable reflecting dynamic changes in the rates of cellulose hydrolysis and acidogenesis, acetoclastic and hydrogenotrophic methanogenesis. As CO2 is the substrate in hydrogenotrophic methanogenesis, δ13 C-CO2 increased from the start till the dissolved hydrogen concentration became very low...
October 2018: Isotopes in Environmental and Health Studies
Biao Jin, Ivonne Nijenhuis, Massimo Rolle
We performed a model-based investigation to simultaneously predict the evolution of concentration, as well as stable carbon and bromine isotope fractionation during 1,2-dibromoethane (EDB, ethylene dibromide) transformation in a closed system. The modelling approach considers bond-cleavage mechanisms during different reactions and allows evaluating dual carbon-bromine isotopic signals for chemical and biotic reactions, including aerobic and anaerobic biological transformation, dibromoelimination by Zn(0) and alkaline hydrolysis...
August 2018: Isotopes in Environmental and Health Studies
Suman Som, Gourab Dutta Banik, Abhijit Maity, Chiranjit Ghosh, Sujit Chaudhuri, Manik Pradhan
Helicobacter pylori causes several gastrointestinal diseases and may also contribute to the development of type 2 diabetes (T2D). Several studies suggest that there might be a potential link between H. pylori infection and T2D, but it still remains the subject of debate. Here, we first report the cumulative effect of H. pylori infection and T2D by exploiting the excretion kinetics of 13 C/12 C and 18 O/16 O isotope ratios of exhaled breath CO2 in response to an oral dose of 13 C-enriched glucose in individuals with T2D and non-diabetic controls (NDC) harbouring the H...
August 2018: Isotopes in Environmental and Health Studies
Joseph Asante, David K Kreamer
In the Basin and Range Province of the Southwestern U.S.A., deep carbonate groundwater has been suggested as a significant source to many overlying basin-fill alluvial aquifer systems. Notwithstanding, testing this hypothesis is limited by obtaining data from such considerable depths and complex geology. This study uses δ2 H and δ18 O data from springs, rivers, and wells tapping shallow basin-fill groundwater to test the hydrochemical interpretation of deep regional carbonate groundwater flow into the basin-fill aquifers...
August 2018: Isotopes in Environmental and Health Studies
Ibrahim H Saleh, Aly A Abdel-Halim
Beryllium-7 is a radionuclide produced in the upper atmosphere by cosmic-ray spallation with ions of carbon, oxygen and nitrogen. It is one of radionuclides that can be used to trace the fine particulate matter of 2.5-µm diameter (PM2.5 ) and smaller. In this work, 7 Be was determined in leaves of 10 plant species collected from streets, parks and open land and in 5 consecutive rains over Alexandria, Egypt. 7 Be levels were also measured in soil covered by each type of plant as well as in the nearest uncovered soil to be reference values to determine its intercepted amount and consequently PM2...
August 2018: Isotopes in Environmental and Health Studies
Fantine Nivet, Laurent Bergonzini, Pierre-Etienne Mathé, Aurélie Noret, Gaël Monvoisin, Amos Majule, David Williamson
Tropical rainfall isotopic composition results from complex processes. The climatological and environmental variability in East Africa increases this complexity. Long rainfall isotope datasets are needed to fill the lack of observations in this region. At Kisiba Masoko, Tanzania, rainfall and rain isotopic composition have been monitored during 6 years. Mean year profiles allow to analyse the seasonal variations. The mean annual rainfall is 2099 mm with a rain-weighted mean composition of -3.2 ‰ for δ18 O and -11...
August 2018: Isotopes in Environmental and Health Studies
Michael Thoma, Jay Frentress, Massimo Tagliavini, Francesca Scandellari
We used pore water samplers (PWS) to sample for isotope analysis (1) only water, (2) soil under laboratory conditions, and (3) soil in the field comparing the results with cryogenic extraction (CE). In (1) and (2), no significant differences between source and water extracted with PWS were detected with a mean absolute difference (MAD) always lower than 2 ‰ for δ2 H and 1 ‰ for δ18 O. In (2), CE water was more enriched than PWS-extracted water, with a MAD respect to source water of roughly 8 ‰ for δ2 H and 4 ‰ for δ18 O...
August 2018: Isotopes in Environmental and Health Studies
Dragana Filipović, Uroš Gašić, Nikola Stevanović, Dragana Dabić Zagorac, Milica Fotirić Akšić, Maja Natić
The carbon stable isotope content of Cornelian cherry stones collected from wild tree stands in Serbia, SE Europe, was measured using elemental analyser-isotope ratio mass spectrometry, with the aim of recording natural carbon isotope composition of the fruit stones and its possible variation. The results show a significant variation in the carbon isotope values; we identified several environmental factors that, along with a number of other possible determinants, likely contributed to this variation. The obtained data are compared with the measurement of carbon isotope content of an archaeological specimen of Cornelian cherry stone discovered at the Neolithic site of Vinča (ca...
August 2018: Isotopes in Environmental and Health Studies
Xing Wang, Harro A J Meijer
The stable isotopes of water are extensively used as tracers in many fields of research. For this use, it is essential to know the isotope fractionation factors connected to various processes, the most important of which being phase changes. Many experimental studies have been performed on phase change fractionation over the last decades. Whereas liquid-vapour fractionation measurements are relatively straightforward, vapour-solid and liquid-solid fractionation measurements are more complicated, as maintaining equilibrium conditions when a solid is involved is difficult...
June 2018: Isotopes in Environmental and Health Studies
Frédéric Robin, Philippe Delaporte, Pierre Rousseau, Francis Meunier, Pierrick Bocher
Western France is at the crossroads of the migratory routes of two subspecies of black-tailed godwit, Limosa limosa. After leaving Iceland, the godwit L.l. islandica Icelandic black-tailed godwit (IBTG) winters on the coast of western Europe, while the continental black-tailed godwit (CBTG) L.l. limosa can stop in France when migrating between Iberia or Africa and their main breeding grounds in the Netherlands. In this study, we analysed δ15 N and δ13 C from flight feathers and whole blood throughout the non-breeding period to trace variations in habitat use for both subspecies on the western French coast...
June 2018: Isotopes in Environmental and Health Studies
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