Geochemistry of As-, F- and B-bearing waters in and around San Antonio de los Cobres, Argentina, and implications for drinking and irrigation water quality

Spring, stream and tap waters from in and around San Antonio de los Cobres, Salta, Argentina, were sampled to characterize their geochemical signatures, and to determine whether they pose a threat to human health and crops. The spring waters are typical of geothermal areas world-wide, in that they are Na-Cl waters with high concentrations of Astot, As(III), Li, B, HCO3, F and SiO2 (up to 9.49, 8.92, 13.1, 56.6, 1250, 7.30 and 57.2 mg L-1, respectively), and result from mixing of deep Na-Cl brines and meteoric HCO3-rich waters. Springs close to the town of San Antonio have higher concentrations of all elements, and are generally cooler, than springs in the Baños de Agua Caliente. Spring water chemistry is a result of mixing of deep Na-Cl brines and meteoric HCO3 waters. Stream waters are also Na-Cl type, and receive large inputs of all elements from the springs near San Antonio, but concentrations decrease downstream through the town of San Antonio due to mineral precipitation. The spring that is used as a drinking water source, and other springs in the area, have As, F and B concentrations in excess of WHO and Argentinian drinking water guidelines. Evaluation of the waters for irrigation purposes suggests that their high salinities and B concentrations may adversely affect crops. The waters may be improved for drinking and irrigation by dilution with cleaner meteoric waters, mineral precipitation or by use of commercial filters. Such recommendations could also be followed by other settlements that draw drinking and irrigation waters from geothermal sources

Species-specific responses of Late Quaternary megafauna to climate and humans

Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary remain contentious. We use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, underscoring the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change.This paper is in the memory of our friend and colleague Dr. Andrei Sher, who was a major contributor of this study. Dr Sher died unexpectedly, but his major contributions to the field of Quaternary science will be remembered and appreciated for many years to come. We are grateful to Dr. Adrian Lister and Dr. Tony Stuart for guides and discussions. Thanks to Tina B. Brandt, Dr. Bryan Hockett and Alice Telka for laboratory help and samples and to L. Malik R. Thrane for his work on the megafauna locality database. Data taken from the Stage 3 project was partly funded by Grant #F/757/A from the Leverhulme Trust, together with a grant from the McDonald Grants and Awards Fund. We acknowledge the Danish National Research Foundation, the Lundbeck Foundation, the Danish Council for Independent Research and the US National Science Foundation for financial suppor

Oxygen Isotopes and Human Residential Mobility in Central Western Argentina

Stable oxygen isotopes (δ18O) from human bone apatite from central western Argentina (30º–37ºS latitude) were analysed to understand changes in human residential mobility during the Late Holocene. This region contains evidence for the use of domesticated plants over the last 2000 years (Zea mays, Cucurbita sp. and Phaseolus sp., among others), and previous models of prehistoric occupation have suggested a distinct change in mobility and population movement associated with their incorporation. The importance of these domesticates also seems to have varied geographically, being greater in the northern part of the region and declining as one moves south toward the limit with Patagonia. Expectations about patterns of residential mobility have varied accordingly. To better evaluate these models, we analysed carbonate δ18O from the bone apatite of 71 individuals with radiocarbon dates spanning the last 6000 years. Given the existing evidence, we expected to see temporal and geographic differences in their oxygen isotope values associated with changes in residential mobility and the incorporation of different sources of drinking water available within the region. These expectations were not met. Significant variations were seen across all samples compared, both temporal and geographic, with no discernible differences among them. The data suggest that populations throughout the area were all highly mobile, and that this did not change with the incorporation of domesticates. Copyright © 2011 John Wiley & Sons, Ltd

Human demography and domestic plants in central Western Argentina: Exploring trends in radiocarbon dates

Clásicamente el origen y la dispersión de la agricultura se han explicado al menos parcialmente por variables demográficas. Este estudio, de carácter preliminar, explora el uso de la frecuencia de fechas radiocarbónicas como un proxy demográfico y con tales tendencias se compara la dispersión de cultígenos en el centro occidente argentino. Se acepta la región como el límite sur de la expansión agrícola prehispánica y sobre esa base se comparan las tendencias radiocarbónicas de tres sectores definidos heurísticamente: Norte, Centro y Sur. El trabajo analiza 344 fechas para los últimos 5000 años 14C provenientes de 166 sitios arqueológicos. La suma de probabilidades muestra patrones similares entre los tres sectores pero registra menos variaciones temporales en el Norte, luego en el Centro y finalmente en el Sur, lo que podría entenderse como una correlación con la estabilidad demográfica donde el sector Norte muestra un patrón más estable que en el Centro y estos que el Sur.Classically, the origin and spread of the farmers at least have been explained by demographics variable. This paper preliminarily explores the use of the frequency of radiocarbon dates as a demographic proxy and compares such trends to cultigens scattering in central western Argentina. The region is accepted as the southern boundary of Prehispanic agricultural expansion and on that basis the radiocarbon trends compare three sectors: North, Central and South. The paper analyzes 344 radiocarbon dates from the last 5000 14C years and 176 archaeological site recorded between 30° and 37° S. The sum of probabilities shows similar patterns among the three sectors but less variation recorded in the North than in Center and the South. This could indicate a correlation with demographic stability where the North shows a more stable than those in the Center and the South pattern.Fil: Gil, Adolfo Fabian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; ArgentinaFil: Giardina, Miguel Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; ArgentinaFil: Neme, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; ArgentinaFil: Ugan, A.. University of Utah; Estados Unidos. Museo de Historia Natural de San Rafael; Argentin

Nephroprotective potential of carnitine against glycerol and contrast-induced kidney injury in rats through modulation of oxidative stress, proinflammatory cytokines, and apoptosis

Karaman, Adem/0000-0002-3091-0609; UGAN, RUSTEM ANIL/0000-0002-4837-2343; POLAT, Beyzagul/0000-0003-2042-5949; ATMACA, HASAN TARIK/0000-0001-8379-4114; UN, Harun/0000-0003-1772-282XWOS: 000368422100001PubMed: 26562095Objective: Contrast media (CM) are a major cause of nephropathy in high-risk patients. The aim of this study was to examine the effects of carnitine (CAR) in advanced nephrotoxicity due to CM administration in rats with glycerol-induced renal functional disorder. Methods: 40 rats were divided randomly into five groups (n=8): (1) healthy group; (2) glycerol only (GLY); (3) glycerol and CM (GLY1CM); (4) glycerol, CM and 200 mg kg(-1) carnitine (CAR200, Carnitene (R); Sigma-tau/Santa Farma, Istanbul, Turkey); and (5) glycerol, CM and 400 mg kg(-1) carnitine (CAR400). Kidney injury was induced with a single-dose, intramuscular injection of 10 ml kg(-1) body weight (b.w.) of GLY. CAR was administered intraperitoneally. CM (8 ml kg(-1) b.w. iohexol, Omni-paque (TM) T; Opakim Medical Products, Istanbul, Turkey) was infused via the tail vein to the rats in Groups 3-5. Results: L-carnitine administration significantly decreased serum creatinine and blood urea nitrogen levels. Superoxide dismutase and glutathione activity increased significantly in the treatment groups compared with the nephrotoxic groups. CAR400 significantly reduced malondialdehyde levels to healthy levels. In the treatment groups, tumour necrosis factor (TNF)-beta, transforming growth factor 1 beta, interleukin 1 beta and caspase-3 gene expression decreased compared with the nephrotoxic groups. TNF-alpha and nuclear factor kappa-beta (NF-kappa B) protein expression increased after CM and CAR administration reduced both TNF-alpha and NF-kappa B expressions. Histopathologically, hyaline and haemorrhagic casts and necrosis in proximal tubules increased in the nephrotoxicity groups and decreased in the CAR groups. Conclusion: The results reveal that L-carnitine protects the oxidant/antioxidant balance and decreases proinflammatory cytokines and apoptosis in CM-induced nephrotoxicity in rats with underlying pathology. Advances in knowledge: Depending on the underlying kidney pathologies, the incidence of CM-induced nephropathy (CIN) increases. Therefore, this is the best model to represent clinically observed CIN. Advances in knowledge: Depending on the underlying kidney pathologies, the incidence of CM-induced nephropathy (CIN) increases. Therefore, this is the best model to represent clinically observed CIN.Ataturk University Scientific Experimental Project OfficeAtaturk University [2013/52]This work was supported by the Ataturk University Scientific Experimental Project Office through project number: 2013/52