24 research outputs found

    MISO DC-DC Farmbot

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    Making use of renewable energy directly from the location of production requires converting source power into usable power. The specific scope of this project focuses on the DC to DC conversion within a user friendly universal farmbot system. Since renewable sources vary widely in voltage and current, a wide input-range DC to DC converter is desired. Physical isolation, long lifespan, and adverse weather requires safe and reliable final product specifications. The goal of a very wide customer base drives the need for a product that does not require tinkering to get working, but to be usable out of the box for a vast majority of energy sources. This project designs, purely through simulation due to COVID-19 pandemic, a Universal Input Module (UIM) DC-DC converter, which acts as the first step from the energy source to the usable power bus. UIMs can be connected in parallel to effectively make a Multiple Input Single Output (MISO) system. The main component of conversion is a 4-switch buck-boost controller. Input filtering, output filtering, parallel function, and two theoretical renewable inputs are incorporated to give the simulated converter as realistic of a function as possible. The selection process for all main components, surrounding components, and equivalent simulation circuits is included. With use of LTSpice, the simulation results meet the customer’s specifications

    Freshwater ecoregions of the world: A new map of biogeographic units for freshwater biodiversity conservation

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    We present a new map depicting the first global biogeographic regionalization of Earth's freshwater systems. This map of freshwater ecoregions is based on the distributions and compositions of freshwater fish species and incorporates major ecological and evolutionary patterns. Covering virtually all freshwater habitats on Earth, this ecoregion map, together with associated species data, is a useful tool for underpinning global and regional conservation planning efforts (particularly to identify outstanding and imperiled freshwater systems); for serving as a logical framework for large-scale conservation strategies; and for providing a global-scale knowledge base for increasing freshwater biogeographic literacy. Preliminary data for fish species compiled by ecoregion reveal some previously unrecognized areas of high biodiversity, highlighting the benefit of looking at the world's freshwaters through a new framework.La lista completa de autores que integran el documento puede consultarse en el archivo.Facultad de Ciencias Naturales y Muse

    Freshwater ecoregions of the world: A new map of biogeographic units for freshwater biodiversity conservation

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    We present a new map depicting the first global biogeographic regionalization of Earth's freshwater systems. This map of freshwater ecoregions is based on the distributions and compositions of freshwater fish species and incorporates major ecological and evolutionary patterns. Covering virtually all freshwater habitats on Earth, this ecoregion map, together with associated species data, is a useful tool for underpinning global and regional conservation planning efforts (particularly to identify outstanding and imperiled freshwater systems); for serving as a logical framework for large-scale conservation strategies; and for providing a global-scale knowledge base for increasing freshwater biogeographic literacy. Preliminary data for fish species compiled by ecoregion reveal some previously unrecognized areas of high biodiversity, highlighting the benefit of looking at the world's freshwaters through a new framework.La lista completa de autores que integran el documento puede consultarse en el archivo.Facultad de Ciencias Naturales y Muse

    Rapid spatiotemporal variations in rift structure during development of the Corinth Rift, central Greece

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    The Corinth Rift, central Greece, enables analysis of early rift development as it is young (<5Ma) and highly active and its full history is recorded at high resolution by sedimentary systems. A complete compilation of marine geophysical data, complemented by onshore data, is used to develop a high-resolution chronostratigraphy and detailed fault history for the offshore Corinth Rift, integrating interpretations and reconciling previous discrepancies. Rift migration and localization of deformation have been significant within the rift since inception. Over the last circa 2Myr the rift transitioned from a spatially complex rift to a uniform asymmetric rift, but this transition did not occur synchronously along strike. Isochore maps at circa 100kyr intervals illustrate a change in fault polarity within the short interval circa 620-340ka, characterized by progressive transfer of activity from major south dipping faults to north dipping faults and southward migration of discrete depocenters at ~30m/kyr. Since circa 340ka there has been localization and linkage of the dominant north dipping border fault system along the southern rift margin, demonstrated by lateral growth of discrete depocenters at ~40m/kyr. A single central depocenter formed by circa 130ka, indicating full fault linkage. These results indicate that rift localization is progressive (not instantaneous) and can be synchronous once a rift border fault system is established. This study illustrates that development processes within young rifts occur at 100kyr timescales, including rapid changes in rift symmetry and growth and linkage of major rift faults

    Freshwater ecoregions of the world: A new map of biogeographic units for freshwater biodiversity conservation

    Get PDF
    We present a new map depicting the first global biogeographic regionalization of Earth's freshwater systems. This map of freshwater ecoregions is based on the distributions and compositions of freshwater fish species and incorporates major ecological and evolutionary patterns. Covering virtually all freshwater habitats on Earth, this ecoregion map, together with associated species data, is a useful tool for underpinning global and regional conservation planning efforts (particularly to identify outstanding and imperiled freshwater systems); for serving as a logical framework for large-scale conservation strategies; and for providing a global-scale knowledge base for increasing freshwater biogeographic literacy. Preliminary data for fish species compiled by ecoregion reveal some previously unrecognized areas of high biodiversity, highlighting the benefit of looking at the world's freshwaters through a new framework.La lista completa de autores que integran el documento puede consultarse en el archivo.Facultad de Ciencias Naturales y Muse

    Reviewing horizontalization: the challenge of analysis in Brazilian foreign policy

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    Caracterización del patrón alimentario de las personas mayores de Iberoamérica en tiempos de pandemia por COVID 19

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    "Objetivo: Caracterizar el perfil alimentario de las Personas Mayores de Iberoamérica en tiempos de pandemia por COVID 19. Material y métodos: Estudio multicéntrico en 12 países de Iberoamérica, se aplicó una encuesta en línea que incluyó preguntas sociodemográficas y un cuestionario de Ingesta de Alimentos que incluyo la frecuencia de consumo para verduras, bebidas azucaradas, legumbres, lácteos y porción de los alimentos. Resultados: La muestra quedó conformada por 624 participantes, 72,1% (n= 450) de mujeres. El 54,7% de mujeres no consume bebidas azucaradas, en cambio en hombres un 54% consume al menos un vaso al día (p=0,012). El 35,6% de hombres consumieron ≥3 por semana legumbres versus el 23% mujeres (p=0,020). El 37,3% de las mujeres consumen ≥2 porciones diarias de lácteos, en hombres solo un 28,1% (p= 0,030). Las mujeres presentan un mayor consumo de verduras (44,7%, n= 201) respecto de los hombres (28,7%), (p=0,001). El 17,4% de la muestra total aumentó el tamaño de la porción de alimentos, sin do mayor en mujeres (p=0.005). Conclusión: Las mujeres presentan hábitos alimentarios más saludables que los hombres en base a frutas, verduras, por otra parte, la variación del tamaño se observa un incremento en especial en mujeres lo que puede relacionarse con el aumento de la obesidad.

    Quality of the diet during the COVID-19 pandemic in 11 Latin-American countries

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    BACKGROUND AND OBJECTIVES: The confinement by COVID-19 has affected the food chain and environments, which added to factors such as anxiety, frustration, fear and stress have modified the quality of the diet in the population around the world. The purpose of this study was to explore diet quality during the COVID-19 pandemic in 11 Latin American countries. METHODOLOGY: Multicentric, cross-sectional study. An online survey was applied to residents of 11 Latin-American countries, during April and May 2020, when confinement was mandatory. Diet quality was evaluated using a validated questionnaire. RESULT: 10,573 people participated in the study. The quality of the food by country shows that Colombia presented the best quality, while Chile and Paraguay presented the lowest. When comparing the overall results of diet quality by gender, schooling and age, women, people with more schooling and people under 30 years of age, presented better diet quality. The regression model showed that the variables associated with diet quality were: age (df = 3, F = 4. 57, p < 0.001), sex (df = 1, F = 131.01, p < 0.001), level of education (df = 1, F = 38.29, p < 0.001), perception of weight change (df = 2, F = 135.31, p < 0.001), basis services (df = 1, F = 8.63, p = 0.003), and quarantine (df = 1, F = 12.14, p = 0.001). CONCLUSION: It is necessary for governments to intervene to reverse these indicators, considering that inadequate feeding favors the appearance of no communicable diseases, which favor a higher risk of infection and worse prognosis with COVID-19
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