scholarly journals Reinterpreting Models of Slope-Front Recharge in a Desert Basin

Geosciences ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 297
Author(s):  
Barry J. Hibbs ◽  
Mercedes Merino
Keyword(s):  
El Paso ◽  
Rio Grande ◽  
Spatial And Temporal Variability ◽  
Stable Water Isotopes ◽  
Lateral Contact ◽  
Groundwater Samples ◽  
Alluvial Floodplain ◽  
Hueco Bolson ◽  
Floodplain Deposits

Identification of recharge areas in arid basins is challenging due to spatial and temporal variability and complexity of the hydrogeology. This study re-evaluates recharge mechanism in a desert basin where isotopic and geologic data indicated that published conceptual models of recharge are not accurate. A new model of recharge is formulated that is consistent with the unique geologic framework in the basin. In the area of study, the Rio Grande flows across a broad alluvial floodplain, the “El Paso-Juarez Valley”, where the river has incised the surface of the Hueco Bolson. The modern Rio Grande floodplain overlies the older basin fill, or “Hueco Bolson deposits”, in the valley portion of the area. The lateral contact between the older bolson deposits and the recent alluvial floodplain deposits defines the “slope front”. The valley wall along the slope front is penetrated by many arroyos that incise the Hueco Bolson deposits and modern floodplain surface. The presence of a large lens of freshwater at the boundary between the older bolson fill and recent Rio Grande alluvium seemed to suggest to previous researchers that dilute water developed due to runoff drawn in by San Felipe Arroyo, a prominent arroyo at the slope front between the older Hueco Bolson deposits and the recent Rio Grande alluvium. Our follow-up verification work illustrates that this is demonstrably not the case. The testing of groundwater samples for stable water isotopes and radioisotopes showed that the deeper and more dilute waters near San Felipe Arroyo are actually pre-dam waters recharged from the shifting Rio Grande channel.

scholarly journals Cohort study of ageing from Bagé (SIGa-Bagé), Brazil: profile and methodology

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elaine Thumé ◽  
Marciane Kessler ◽  
Karla P. Machado ◽  
Bruno P. Nunes ◽  
Pamela M. Volz ◽  
...  
Keyword(s):  
Older Adults ◽  
Health Care ◽  
Cohort Study ◽  
Primary Health Care ◽  
Rio Grande ◽  
Cognitive Testing ◽  
Rio Grande Do Sul ◽  
Primary Health ◽  
The Impact

Abstract Background The Bagé Cohort Study of Ageing is a population-based cohort study that has recently completed the first follow-up of a representative sample of older adults from Bagé, a city with more than 100,000 inhabitants located in the state of Rio Grande do Sul, Brazil. This is one of the first longitudinal studies to assess the impact of primary health care coverage on health conditions and inequalities. Our aim is to investigate the prevalence, incidence and trends of risk factors, health behaviours, social relationships, non-communicable diseases, geriatric diseases and disorders, hospitalisation, self-perceived health, and all-cause and specific-cause mortality. In addition, we aim to evaluate socioeconomic and health inequalities and the impact of primary health care on the outcomes under study. Methods/design The study covers participants aged 60 or over, selected by probabilistic (representative) sampling of the urban area of the city of Bagé, which is covered by Primary Health Care Services. The baseline examination included 1593 older adults and was conducted from July 2008 to November 2008. After eight to nine years (2016/2017), the first follow-up was conducted from September 2016 to August 2017. All participants underwent an extensive core assessment programme including structured interviews, questionnaires, cognitive testing (baseline and follow-up), physical examinations and anthropometric measurements (follow-up). Results Of the original participants, 1395 (87.6%) were located for follow-up: 757 elderly individuals (47.5%) were re-interviewed, but losses in data transfer occurred for 22. The remaining 638 (40.1%) had died. In addition, we had 81 (5.1%) refusals and 117 (7.3%) losses. Among the 1373 older adults who were followed down, there was a higher proportion of female interviewees (p=0.042) and a higher proportion of male deaths (p=0.001) in 2016/2017. There were no differences in losses and refusals according to gender (p=0.102). There was a difference in average age between the interviewees (68.8 years; SD ±6.5) and non-interviewees (73.2 years; SD ±9.0) (p<0.001). Data are available at the Department of Social Medicine in Federal University of Pelotas, Rio Grande do Sul, Brazil, for any collaboration.

scholarly journals An Optimized Snowmelt Lysimeter System for Monitoring Melt Rates and Collecting Samples for Stable Water Isotope Analysis

2019 ◽  
Vol 67 (1) ◽  
pp. 20-31 ◽  
Author(s):  
Andrea Rücker ◽  
Massimiliano Zappa ◽  
Stefan Boss ◽  
Jana von Freyberg
Keyword(s):  
Isotopic Composition ◽  
Isotope Analysis ◽  
Ground Level ◽  
Isotopic Signature ◽  
Small Scale ◽  
Spatial And Temporal Variability ◽  
Environmental Tracers ◽  
Hydrograph Separation ◽  
Stable Water Isotopes ◽  
Restricted Volume

Abstract The contribution of snow meltwater to catchment streamflow can be quantified through hydrograph separation analyses for which stable water isotopes (18O, 2H) are used as environmental tracers. For this, the spatial and temporal variability of the isotopic composition of meltwater needs to be captured by the sampling method. This study compares an optimized snowmelt lysimeter system and an unheated precipitation collector with focus on their ability to capture snowmelt rates and the isotopic composition of snowmelt. The snowmelt lysimeter system consists of three individual unenclosed lysimeters at ground level with a surface of 0.14 m2 each. The unheated precipitation collector consists of a 30 cm-long, extended funnel with its orifice at 2.3 m above ground. Daily snowmelt samples were collected with both systems during two snowfall-snowmelt periods in 2016. The snowmelt lysimeter system provided more accurate measurements of natural melt rates and allowed for capturing the small-scale variability of snowmelt process at the plot scale, such as lateral meltwater flow from the surrounding snowpack. Because of the restricted volume of the extended funnel, daily melt rates from the unheated precipitation collector were up to 43% smaller compared to the snowmelt lysimeter system. Overall, both snowmelt collection methods captured the general temporal evolution of the isotopic signature in snowmelt.

scholarly journals Pharmaceutical support in liver transplantation at a reference center in Rio Grande do Sul

2017 ◽  
Vol 20 (2) ◽  
pp. 6-8
Author(s):  
Mariana de Andrade Pranke ◽  
Maria Lúcia Zanotelli ◽  
Alfeu Fleck Jr. ◽  
Ajácio Brandão ◽  
Cláudio Marroni ◽  
...  
Keyword(s):  
Liver Transplantation ◽  
Dose Adjustment ◽  
Rio Grande ◽  
New Drugs ◽  
Rio Grande Do Sul ◽  
Treatment Results ◽  
Reference Center ◽  
Transplant Patients ◽  
Transplantation Center

The introduction of the everolimus as immunosuppressant in the liver transplantation has been shown to be safe and effective in the prophylaxis and preservation of the renal function. Prospective follow-up and chart analysis of liver transplant patients treated with everolimus was performed. Purpose: To highlight the importance of the pharmacist in transplantation centers. Method: Along the study, 93 patients were included, being 72 under active treatment. The successful treatment depends on the multidisciplinary follow-up, and it is extremely important the involvement of the patient, making him to become positive and an active part of the treatment. Results: The most frequent problems were: patients cutting the everolimus tablet, late SL after dose adjustment, lack of adhesion to the collection, and serum level collection out of time. Discussion: Upon the introduction of new drugs, it is required to observe possible adverse events further to ensure that the patient correctly follows the treatment. Conclusion: The presence of the pharmacist in the transplantation center allows the patient to get a reference to clarify doubts on the proper use of immunosuppressant.

scholarly journals Bioativador no desempenho fisiológico de sementes de arroz

2011 ◽  
Vol 33 (3) ◽  
pp. 501-510 ◽  
Author(s):  
Andréia da Silva Almeida ◽  
Ireni Carvalho ◽  
Cristiane Deuner ◽  
Maria ângela André Tillmann ◽  
Francisco Amaral Villela
Keyword(s):  
El Paso ◽  
Rio Grande ◽  
Rio Grande Do Sul

O arroz é, dentre os diversos cereais cultivados no mundo, um dos mais importantes, por se tratar de um alimento básico da maioria da população mundial e uma das culturas mais antigas. O Estado do Rio Grande do Sul ocupa lugar de destaque na cultura, respondendo por 50% da produção nacional sendo que 80% é arroz irrigado. O tiametoxam, é um inseticida sistêmico que é transportado dentro da planta através de suas células e pode ativar várias reações fisiológicas como a expressão de proteínas. Estas proteínas interagem com mecanismos de defesa de estresses, permitindo que a planta suporte melhor condições adversas, tais como secas, baixo pH, alta salinidade de solo, radicais livres, estresses por elevadas temperaturas, efeitos tóxicos de níveis elevados de alumínio, ferimentos causados por pragas, ventos, granizo, ataque de viroses e deficiência de nutrientes. O objetivo deste trabalho foi avaliar a influência do tiametoxam no desempenho fisiológico de sementes de arroz. Foram utilizadas sementes de arroz, das cultivares El Paso, IRGA BR 410, IRGA BR 424 e Olimar tratadas nas concentrações de 0,0, 50, 100, 200, 400 mL do produto para 100 kg de sementes. Para a avaliação da qualidade fisiológica das sementes foram conduzidos os testes de germinação, primeira contagem de germinação, teste de frio, envelhecimento acelerado e comprimento de plântula, parte aérea e radicular. O tratamento de sementes de arroz com tiametoxam favorece positivamente a qualidade fisiológica das sementes. As doses de 300 a 400 mL de produto para 100 kg de semente proporcionam melhor desempenho fisiológico de sementes de arroz.

Thermoluminescence dating tests for lacustrine, glaciomarine, and floodplain sediments from western Washington and British Columbia

1993 ◽  
Vol 30 (9) ◽  
pp. 1815-1828 ◽  
Author(s):  
Glenn W. Berger ◽  
Don J. Easterbrook
Keyword(s):  
Flood Plain ◽  
Last Interglacial ◽  
Tl Dating ◽  
Sediment Types ◽  
Three Samples ◽  
Two Samples ◽  
Drift Sample ◽  
Floodplain Deposits ◽  
Floodplain Sediments

To help further develop reliable procedures for accurate thermoluminescence (TL) dating of Quaternary waterlaid sediments, we tested TL dating procedures on sediment types rarely examined: six glaciolacustrine samples, three samples of glaciomarine drift, and eight samples of floodplain deposits. We used the partial-bleach (R-beta/gamma) technique applied to fine-silt polymineral grains. Results from our younger known-age glaciolacustrine sediments confirm earlier observations that only the clayey laminae are generally suitable for TL dating. A clayey lamina older than ca. 140 – 150 ka produced no age underestimation, and this result (ca. 300 ka) suggests that such older lake sediments are probably suitable for TL dating. Two proximal samples of glaciomarine drift produced large TL age overestimates, whereas the single distal glaciomarine-drift sample yielded an expected age (177 ± 38 ka), suggesting that follow-up studies are warranted. Our results for eight flood-plain samples confirm that zeroing of light-sensitive TL is more likely to be effective for sediments deposited in quiet, ponded water on the floodplain than for proximal sediments deposited from turbid floodwater. TL age estimates for floodplain sediments of the regional Whidbey Formation are consistent with its expected last-interglacial age, and those for two samples from stratigraphically older beds are consistent with deposition near or beyond 200 ka. Two of our younger samples (one lacustrine and one floodplain) gave TL age underestimates, perhaps because of use of ultraviolet TL emissions for these samples.

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