31 research outputs found

    Streamflow variations across the Andes (18°–55°S) during the instrumental era

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    The rivers originating in the southern Andes (18°–55°S) support numerous ecosystems and a large number of human populations and socio-economic activities in the adjacent lowlands of Chile, Argentina and Bolivia. Here we show that ca. 75% of the total variance in the streamflow records from this extensive region can be explained by only eight spatially coherent patterns of variability. Five (three) of these Andean patterns exhibit extreme dry (wet) conditions in recent years, with strong interannual variations in northern Chile; long-term drying trends between 31° and 41°S; a transitional pattern in the central Patagonian Andes; and increasing trends in northwestern Argentina and southern Bolivia, the Fueguian Andes, and the eastern portion of the South Patagonian Icefield. Multivariate regression analyses show that large-scale indices of ENSO variability can predict 20% to 45% of annual runoff variability between 28° and 46°S. The influence of Antarctic and North Pacific indices becomes more relevant south of 43°S and in northwestern Argentina and southern Bolivia, respectively, but their overall skill as predictors of Andean streamflows is weak. The analyses provide relevant new information to improve understanding of the spatial coherence, the main temporal features, and the ocean-atmospheric forcings of surface runoff across the southern Andes.Fil: Masiokas, Mariano Hugo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Cara Ramirez, Leandro Javier. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Villalba, Ricardo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Pitte, Pedro Miguel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Luckman, B. H.. University of Western Ontario; CanadĂĄFil: Toum, Jorge Ezequiel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Christie, D. A.. Universidad Austral de Chile; Chile. Center For Climate And Resilience Research; ChileFil: Le Quesne, C.. Universidad Austral de Chile; ChileFil: Mauget, S.. United States Department of Agriculture. Agriculture Research Service; Estados Unido

    Characterization of street food consumption in palermo: possible effects on health

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    <p>Abstract</p> <p>Background</p> <p>Street Food (SF) consists of out-of-home food consumption and has old, historical roots with complex social-economic and cultural implications. Despite the emergence of modern fast food, traditional SF persists worldwide, but the relationship of SF consumption with overall health, well-being, and obesity is unknown.</p> <p>Methods</p> <p>This is an observational, cross-sectional study. The study was performed in Palermo, the largest town of Sicily, Italy. Two groups were identified: consumers of SF (n = 687) and conventional restaurant food (RES) consumers (n = 315). Study subjects answered a questionnaire concerning their health conditions, nutritional preferences, frequency of consumption of SF and a score relative to SF consumption ranging from 0 to 20 was calculated.</p> <p>Results</p> <p>Body mass index (BMI, kg/m<sup>2</sup>) was significantly and independently correlated with the score of street food consumption (r = 0,103; p < 0.002). The prevalence of different diseases, including hypertension and type 2 diabetes, and the use of medications did not differ between the two groups. Milza (a sandwich stuffed with thin slice of bovine spleen and lung) consumers had a significantly higher prevalence of hypertension (12.2% vs 6.2% in non consumers; p < 0.005) and in this subgroup the use of anti-hypertensive drugs was inversely correlated with the frequency of milza consumption (r = 0.11; P = 0.010).</p> <p>Conclusions</p> <p>This study suggests that SF consumption in Palermo is associated with a higher BMI and higher prevalence of hypertension in milza consumers. Further studies should evaluate whether frequent SF consumers have unfavourable metabolic and cardiovascular profile.</p

    A New Multidisciplinary Home Care Telemedicine System to Monitor Stable Chronic Human Immunodeficiency Virus-Infected Patients: A Randomized Study

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    BACKGROUND: Antiretroviral therapy has changed the natural history of human immunodeficiency virus (HIV) infection in developed countries, where it has become a chronic disease. This clinical scenario requires a new approach to simplify follow-up appointments and facilitate access to healthcare professionals. METHODOLOGY: We developed a new internet-based home care model covering the entire management of chronic HIV-infected patients. This was called Virtual Hospital. We report the results of a prospective randomised study performed over two years, comparing standard care received by HIV-infected patients with Virtual Hospital care. HIV-infected patients with access to a computer and broadband were randomised to be monitored either through Virtual Hospital (Arm I) or through standard care at the day hospital (Arm II). After one year of follow up, patients switched their care to the other arm. Virtual Hospital offered four main services: Virtual Consultations, Telepharmacy, Virtual Library and Virtual Community. A technical and clinical evaluation of Virtual Hospital was carried out. FINDINGS: Of the 83 randomised patients, 42 were monitored during the first year through Virtual Hospital (Arm I) and 41 through standard care (Arm II). Baseline characteristics of patients were similar in the two arms. The level of technical satisfaction with the virtual system was high: 85% of patients considered that Virtual Hospital improved their access to clinical data and they felt comfortable with the videoconference system. Neither clinical parameters [level of CD4+ T lymphocytes, proportion of patients with an undetectable level of viral load (p = 0.21) and compliance levels >90% (p = 0.58)] nor the evaluation of quality of life or psychological questionnaires changed significantly between the two types of care. CONCLUSIONS: Virtual Hospital is a feasible and safe tool for the multidisciplinary home care of chronic HIV patients. Telemedicine should be considered as an appropriate support service for the management of chronic HIV infection. TRIAL REGISTRATION: Clinical-Trials.gov: NCT01117675

    Irradiation temperature monitoring with SiC for RPV steel at low fluence

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    Accurate knowledge of the irradiation temperature is a key concern in irradiations of reactor pressure vessel (RPV) steel. We report results of passive temperature monitoring of RPV steel with SiC. Two un-instrumented capsules containing RPV steel blocks were irradiated in Belgian Reactor 2, at SCK CEN in Belgium. Because un-instrumented capsules were used, the irradiation conditions (gamma heating and irradiation temperature) were calculated. To have experimental verification of the irradiation conditions each capsule contained a passive silicon carbide (SiC) temperature monitor. After irradiation the resistivity and the radiation-induced swelling (lattice parameter) is measured using x-ray diffraction (XRD). These measurements were repeated after annealing treatments to determine the peak irradiation temperature. The best method to determine the peak irradiation temperature with the lowest uncertainty in this study was the resistivity technique. Although lattice parameter measurements could be improved by using ma-terial without preferential orientation. Tensile tests of the RPV blocks were compared to a large available database of RPV material with the proper sensitivity towards neutron fluence and irradiation temperature to find the irradiation temperature of the RPV steel. The data showed a discrepancy between the tem-perature obtained from SiC and the temperature obtained from tensile tests. The temperature differences were discussed and rationalized by finite element modelling with respect to uncertainties in the helium gap between the capsule and the RPV steel block. The aluminium holder accounted for the tempera -ture difference and the use of a steel holder is recommended for future similar irradiations to minimize the temperature difference between SiC and tensile specimens. In-depth analysis showed that when the irradiation temperature dropped at the end of the irradiation for a considerable time, the SiC tempera -ture monitor had a memory effect. In this case the post-irradiation resistivity analysis showed two peak irradiation temperatures with a region of constant resistivity between the two

    Reconstructing glacier mass balances in the Central Andes of Chile and Argentina using local and regional hydro-climatic data

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    Despite the great number and variety of glaciers in southern South America, in situ glacier mass balance records are extremely scarce and glacier climate relationships are still poorly understood in this region. Here we use the longest (> 35 years) and most complete in situ mass balance record, available for glaciar Echaurren Norte in the Andes at ~34° S, to develop a minimal glacier surface mass balance model that relies on nearby monthly precipitation and air temperature data as forcing. This basic model is able to explain 78 % of the variance in the annual glacier mass balance record over the 1978?2013 calibration period. An attribution assessment indicates that precipitation variability constitutes the most important forcing modulating annual glacier mass balances at this site. A regionally-averaged series of mean annual streamflow records from both sides of the Andes is then used to estimate, through simple linear regression, this glacierÂŽs annual mass balance variations since 1909. The reconstruction model captures 68 % of the observed glacier mass balance variability and shows three periods of sustained positive mass balances embedded in an overall negative trend totaling almost −42 m w.eq. over the past 105 years. The three periods of sustained positive mass balances (centered in the 1920s?1930s, in the 1980s and in the first decade of the 21st century) coincide with several documented glacier advances in this region. Similar trends observed in other shorter glacier mass balance series suggest the glaciar Echaurren Norte reconstruction is representative of larger-scale conditions and could be useful for more detailed glaciological, hydrological and climatological assessments in this portion of the Andes.Fil: Masiokas, Mariano Hugo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Christie, D. A.. Universidad Austral de Chile; Chile. Center for Climate and Resilience Research; ChileFil: Le Quesne, C.. Universidad Austral de Chile; ChileFil: Pitte, Pedro Miguel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Ruiz, Lucas Ernesto. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Villalba, Ricardo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de NivologĂ­a, GlaciologĂ­a y Ciencias Ambientales; ArgentinaFil: Luckman, B. H.. University of Western Ontario; CanadĂĄFil: Berthier, E.. Centre National de la Recherche Scientifique; FranciaFil: Nussbaumer, S. U.. University of Fribourg; SuizaFil: GonzĂĄlez Reyes, A.. Universidad de Chile; ChileFil: McPhee, J.. Universidad de Chile; ChileFil: Barcaza, G.. DirecciĂłn General de Aguas; Chil
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