85 research outputs found

    Comment on “Bilaterian Burrows and Grazing Behavior at >585 Million Years Ago”

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    Pecoits et al. (Reports, 29 June 2012, p. 1693) describe bilaterian trace fossils and assign them an Ediacaran age based on the age of a granite interpreted as intrusive. We argue that the granite is not intrusive but in fact represents the basement of the sedimentary succession. Moreover, we show that identical trace fossils occur in nearby Carboniferous-Permian glacigenic rocks.Fil: Gaucher, Claudio. Universidad de la República; UruguayFil: Poire, Daniel Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Bossi, Jorge. Universidad de la República; UruguayFil: Bettucci Sanchez, Leda. Universidad de la República; UruguayFil: Beri, Angeles. Universidad de la República; Urugua

    Ancient Landscapes of Uruguay

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    In this chapter, based on the available geological information, a model for the genesis and evolution of the Uruguayan landscape is proposed. A structural framework of the landscape evolution is provided and the record of such evolution in the most representative geological units is considered. A brief summary of the Uruguayan geology and its location in the regional context is performed, from Precambrian to Cenozoic times.From the analysis of the geological record, it may be observed that the climate was very arid during part of the Jurassic and the Early Cretaceous. Together with the lava flows of the Arapey Formation, the climate became less arid as the Gondwana continents were becoming apart from each other. However, the geological record suggests that semiarid climates were still prevailing. In the Middle Cretaceous, semiarid and wetter climates progressively alternated, until the Early Tertiary, when very wet and warm conditions were established, in coincidence with the ?Paleocene Eocene Thermal Maximum (PETM)?, followed by semiarid climates in the Oligocene, wetter conditions in the Miocene and semiarid again in the Pliocene, with alternating semiarid and humid conditions during the entire Quaternary.On the basis of the paleoclimatic evolution, the development of relief is discussed, considering as bases for the analysis the different morphostructural units in which the country is divided. Due to their size, shape and location (passive margin) of Uruguay, climate uniformity is assumed for each period throughout the entire territory. It is also assumed that the surfaces around elevations of 500 meters correspond to relicts of probably pre-Cretaceous etchplains, strongly denudated, which are observed only in the surroundings of Aiguá.The landforms situated below the oldest surfaces, for instance those below 320 m a.s.l. in the Easthern Hills Regions (Sierra del Este), correspond to a new generation of geomorphological surfaces that may be considered of Cretaceous age, according to the information presently available. This surface may be correlated with the oldest surface developed on top of the lava flows of the Arapey Formation.The extremely warm and wet climate of the Eocene prepared the conditions for the planation processes that covered most of the Uruguayan territory during the Oligocene, generating pediplains which were later reworked during the Late Cenozoic, up to the Quaternary, generating a landscape of smooth hills.The morphogenetic potential of each morphostructural region determined the available energy of the resulting landscape, being this at a minimum in the Santa Lucía Basin, which continued to be under subsidence condition until the Tertiary, and almost non-existant in the Laguna Merín Basin, where subsidence remains active until the Holocene.Fil: Panario, Daniel. Universidad de la República; UruguayFil: Gutierrez, Ofelia. Universidad de la República; UruguayFil: Bettucci Sanchez, Leda. Universidad de la República; UruguayFil: Peel, Elena. Universidad de la República; UruguayFil: Oyhantcabal, Pedro. Universidad de la República; UruguayFil: Rabassa, Jorge Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentin

    Age constraints on the Paleozoic Yaguarí-Buena vista succession from Uruguay: Paleomagnetic and paleontologic information

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    The Yaguarí and the Buena Vista formations from Uruguay are historically correlated to the Brazilian Rio do Rasto and Sanga do Cabral formations, respectively, as they have some lithostratigraphic similarities, indicating a Permo-Triassic or even Triassic age of the Yaguarí-Buena Vista succession. However, they differ in the fossil indexes that characterize the faunistic communities present in both countries. A paleomagnetic work was carried out on some sections of the Buena Vista and the Yaguarí formations, as well as on some layers of bentonites, underlying the Buena Vista sediments. The alternating field and thermal demagnetization procedures revealed both normal and reversed magnetization components, but the samples showed evidence of secondary magnetic minerals and possibly remagnetizations. The calculated paleomagnetic pole for the Yaguarí-Buena Vista Formation plots near to the poles for the Choiyoi magmatism that is believed to be responsible for the bentonite accumulation; it is also in agreement with other Permian paleomagnetic poles for South America. Based on the paleomagnetic results, the available radiometric data for the bentonites, and the fossiliferous content, a Late Permian (Lopingian) age is assigned to the Yaguarí-Buena Vista rocks.Fil: Ernesto, Marcia. Universidade de Sao Paulo; BrasilFil: Núñez Demarco, Pablo Andrés. Universidad de la República. Facultad de Ciencias; Uruguay. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Xavier, Pedro. Universidade Federal do Rio Grande do Sul; BrasilFil: Sanchez, Leda. Universidad de la República. Facultad de Ciencias; UruguayFil: Schultz, Cesar. Universidade Federal do Rio Grande do Sul; BrasilFil: Piñeiro, Graciela. Universidad de la República. Facultad de Ciencias; Urugua

    Historia de la geología precámbrica del Uruguay: Revisión de las divisiones estructurales, tectoestratigráficas sus límites y nomenclaturas

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    En este trabajo presentamos una revisión histórica de la evolución del conocimiento geológico en Uruguay, y particularmente, de las divisiones estructurales precámbricas del territorio nacional. Mostramos su relación contextualizada para cada etapa de la evolución de las teorías y técnicas experimentales regionales y globales. Las divisiones del precámbrico uruguayo comenzaron siendo litológicas según el grado de metamorfismo al que se asociaban. En la década de 1970, la caracterización de las unidades de la región siguió un esquema geocronológico en base a ciclos orogénicos y macizos cristalinos en el marco de la Teoría Geosinclinal. Sólo más tarde, en la década de l980, con el establecimiento y refinamiento de la Teoría de la Tectónica de Placas, comenzaron a dividirse las unidades siguiendo el concepto de cratón y posteriormente, en los 90, según el concepto tectónico de terreno. Así, se establecieron nuevas subdivisiones estructurales que son, de Oeste a Este: el Terreno Piedra Alta, el Terreno Nico Pérez y el Cinturón Dom Feliciano o Cinturón Cuchilla Dionisio y las unidades antagónicas: Terreno Cuchilla Dionisio y Terreno Punta del Este. Sin embargo, cada una de estas unidades presenta sus controversias y divergencias, ya sea en su definición, su nomenclatura o sus límites y se encuentra en constante evolución en la actualidad, entorpeciendo a veces la comprensión de la evolución geológica regional y la ubicación de yacimientos energéticos y minerales. En este trabajo buscamos presentar una revisión bibliográfica sólida para el fundamental entendimiento de los esquemas estructurales y dilucidar las controversias y divergencias de los modelos de evolución geológica del Uruguay actual.Fil: Núñez Demarco, Pablo Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina. Universidad de la República. Facultad de Ciencias; Uruguay. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias Geológicas; ArgentinaFil: Masquelin, Henri. Universidad de la República. Facultad de Ciencias; UruguayFil: Bettucci Sanchez, Leda. Universidad de la República. Facultad de Ciencias; Urugua

    Anxiety, depression, somatization and experiential avoidance indicators in peruvian university students in quarantine by COVID-19

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    Introducción: La cuarentena por COVID-19 ha afectado de gran manera a los estudiantes universitarios del Perú, generando una serie de efectos físicos, psicológicos y conductuales.Objetivo:Determinar los factores asociados a ansiedad, depresión, somatización y evitación experiencial en estudiantes universitarios del Perú en cuarentena por COVID-19. Métodos: Se realizó un estudio observacional transversal. La muestra estuvo constituida por 1264 estudiantes universitarios de diversos departamentos del Perú, se tomó como variables dependientes a la ansiedad, depresión, somatización y evitación experiencial, las cuales se evaluaron con el cuestionario de “El Inventario de comportamiento psicosocial desajustado, ante la presencia del COVID-19 en la población peruana” y el AAQ II, para el análisis estadístico se empleó el chi cuadrado. Resultados:Más de la mitad de los estudiantes universitarios del Perú, presenta entre 3 y 6 de los 6 indicadores de ansiedad, y este mismo número de indicadores de depresión lo presenta el 45% de la muestra. El 30 % de la muestra presenta entre 3 y 6 indicadores de somatización y el 40,3% de la muestra se ubica de la mitad hacia arriba en la escala de evitación experiencial. Conclusiones: Existen diferencias en los niveles de ansiedad, somatización y evitación experiencial entre varones y mujeres, asimismo se encontró que los estudiantes de mayor edad presentaban niveles más bajos de ansiedad, depresión y evitación experiencial, pero no en somatización.Introduction: The COVID-19 quarantine has greatly affected university students in Peru, generating a series of physical, psychological and behavioral effects. Objective: To determine the factors associated with anxiety, depression, somatization and experiential avoidance in peruvian university students quarantined by COVID-19. Methods: A cross-sectional observational study was carried out. The sample was made up of 1264 university students from various departments of Peru, anxiety, depression, somatization and experiential avoidance were taken as dependent variables, which were evaluated with the questionnaire "The Inventory of unadjusted psychosocial behavior, in the presence of COVID-19 in the Peruvian population” and the AAQ II, for the statistical analysis the chi square was used Results: More than half of the university students in Peru present between 3 and 6 of the 6 anxiety indicators, and this same number of depression indicators is presented by 45% of the sample. 30% of the sample has between 3 and 6 indicators of somatization and 40.3% of the sample is located in the middle upwards on the experiential avoidance scale. Conclusions: There are differences in the levels of anxiety, somatization and experiential avoidance between men and women, it was also found that older students had lower levels of anxiety, depression and experiential avoidance, but not in somatization

    Chemically-Induced RAT Mesenchymal Stem Cells Adopt Molecular Properties of Neuronal-Like Cells but Do Not Have Basic Neuronal Functional Properties

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    Induction of adult rat bone marrow mesenchymal stem cells (MSC) by means of chemical compounds (β-mercaptoethanol, dimethyl sulfoxide and butylated hydroxyanizole) has been proposed to lead to neuronal transdifferentiation, and this protocol has been broadly used by several laboratories worldwide. Only a few hours of MSC chemical induction using this protocol is sufficient for the acquisition of neuronal-like morphology and neuronal protein expression. However, given that cell death is abundant, we hypothesize that, rather than true neuronal differentiation, this particular protocol leads to cellular toxic effects. We confirm that the induced cells with neuronal-like morphology positively stained for NF-200, S100, β-tubulin III, NSE and MAP-2 proteins. However, the morphological and molecular changes after chemical induction are also associated with an increase in the apoptosis of over 50% of the plated cells after 24 h. Moreover, increased intracellular cysteine after treatment indicates an impairment of redox circuitry during chemical induction, and in vitro electrophysiological recordings (patch-clamp) of the chemically induced MSC did not indicate neuronal properties as these cells do not exhibit Na+ or K+ currents and do not fire action potentials. Our findings suggest that a disruption of redox circuitry plays an important role in this specific chemical induction protocol, which might result in cytoskeletal alterations and loss of functional ion-gated channels followed by cell death. Despite the neuronal-like morphology and neural protein expression, induced rat bone marrow MSC do not have basic functional neuronal properties, although it is still plausible that other methods of induction and/or sources of MSC can achieve a successful neuronal differentiation in vitro

    Solid waste management; Entrepreneurship strategy for students of the Algarrobo District Educational Institution

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    El manejo de residuos sólidos conduce al reciclaje de materiales desechados por los seres humanos, con el fin de proteger el medio ambiente. En este proyecto se busca crear una estrategia de emprendimiento dirigida a estudiantes de preescolar y básica primaria de la Institución Educativa Distrital de Algarrobo. Este estudio es de tipo cualitativo utilizando la metodología de investigación acción participativa, donde la población estuvo conformada por estudiantes de la IED Algarrobo. Se realizaron entrevistas a los estudiantes para identificar las necesidades de cada sede. Se socializó la temática a desarrollar con los miembros de la comunidad educativa. Para recoger los datos se utilizaron, relatorías individuales, institucionales y diarios de campo. Se implementó la estrategia de formación a los estudiantes en el manejo de residuos sólidos, a través de talleres de manualidades en material reciclado, como estrategia de emprendimiento, generando una fuente de ingresos para el estudiante y su familia.The management of solid waste leads to the recycling of materials discarded by humans, to protect the environment. This project seeks to create an entrepreneurship strategy aimed at preschool and elementary school students of the District Educational Institution of Algarrobo. This study is of qualitative type using the participatory action research methodology, where the population was made up of students from the IED Algarrobo. Interviews were conducted with the students to identify the needs of each location. The topic to be developed with the members of the educational community was socialized. To collect the data, individual, institutional and field diaries were used. The strategy of training students in the management of solid waste was implemented, through craft workshops in recycled material, as a strategy of entrepreneurship generating a source of income for the student and his family

    ECMO for COVID-19 patients in Europe and Israel

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    Since March 15th, 2020, 177 centres from Europe and Israel have joined the study, routinely reporting on the ECMO support they provide to COVID-19 patients. The mean annual number of cases treated with ECMO in the participating centres before the pandemic (2019) was 55. The number of COVID-19 patients has increased rapidly each week reaching 1531 treated patients as of September 14th. The greatest number of cases has been reported from France (n = 385), UK (n = 193), Germany (n = 176), Spain (n = 166), and Italy (n = 136) .The mean age of treated patients was 52.6 years (range 16–80), 79% were male. The ECMO configuration used was VV in 91% of cases, VA in 5% and other in 4%. The mean PaO2 before ECMO implantation was 65 mmHg. The mean duration of ECMO support thus far has been 18 days and the mean ICU length of stay of these patients was 33 days. As of the 14th September, overall 841 patients have been weaned from ECMO support, 601 died during ECMO support, 71 died after withdrawal of ECMO, 79 are still receiving ECMO support and for 10 patients status n.a. . Our preliminary data suggest that patients placed on ECMO with severe refractory respiratory or cardiac failure secondary to COVID-19 have a reasonable (55%) chance of survival. Further extensive data analysis is expected to provide invaluable information on the demographics, severity of illness, indications and different ECMO management strategies in these patients

    ARIA 2016: Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle

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    The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma a

    Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

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    Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe
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