34 research outputs found

    Power electronics converters for an electric vehicle fast charging station with storage capability

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    Fast charging stations are a key element for the wide spreading of Electric Vehicles (EVs) by reducing the charging time to a range between 20 to 40 min. However, the integration of fast charging stations causes some adverse impacts on the Power Grid (PG), namely by the huge increase in the peak demand during short periods of time. This paper addresses the design of the power electronics converters for an EV DC fast charging station with local storage capability and easy interface of renewables. In the proposed topology, the energy storage capability is used to smooth the peak power demand, inherent to fast charging systems, and contributes to the stability of the PG. When integrated in a Smart Grid, the proposed topology may even return some of the stored energy back to the power grid, when necessary. The accomplishment of the aforementioned objectives requires a set of different power electronics converters that are described and discussed in this paper.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and by FCT within the Project Scope: UID/CEC/00319/2013. This work is financed by the ERDF – COMPETE 2020 Programme, and FCT within project SAICTPAC/0004/2015‐POCI‐01‐0145–FEDER‐016434 and FCT within project PTDC/EEI-EEE/28813/2017. Mr. Luis A. M. Barros is supported by the doctoral scholarship PD/BD/143006/2018 granted by the Portuguese FCT agency. Mr. Tiago Sousa is supported by the doctoral scholarship SFRH/BD/134353/2017 granted by the Portuguese FCT agency

    The global biogeography of tree leaf form and habit

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    This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: Tree occurrence data from the Global Forest Biodiversity initiative (GFBi) is available upon request via Science-I (https://science-i.org) or the GFBi website (https://www.gfbiinitiative.org/). Information on leaf habit (evergreen vs deciduous) and leaf form (broadleaved vs needle-leaved) came from the TRY database (https://www.try-db.org). Additional, leaf-type data came from the Tallo dataset (https://zenodo.org/record/6637599). Plot-level soil information came from the World Soil Information Service (WOSIS) dataset (https://www.isric.org/explore/wosis).Code availability: All code is available at https://doi.org/10.5281/zenodo.7967245.Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling

    Endotracheal and upper airways suctioning: changes in newborns’ physiological parameters Aspiración del tubo endotraqueal y de las vías aéreas superiores: alteraciones en los parámetros fisiológicos en recién nacidos Aspiração do tubo orotraqueal e de vias aéreas superiores: alterações nos parâmetros fisiológicos em recém-nascidos

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    This study investigated which physiological parameters change when endotracheal and upper airway suctioning is performed immediately before, immediately after and five minutes after this procedure is performed in newborns hospitalized in a Neonatal Intensive Care Unit (NICU). This is a quantitative and longitudinal study, before and after type, performed in the NICU of a public institution in the city of Fortaleza, CE, Brazil. The sample was composed of 104 newborns using oxigenotherapy and who needed endotracheal and upper airway suctioning. The results showed significant alterations in respiratory and heart rates (p<0.05) in neonates using Oxyhood and nasal CPAP while the pulse significantly changed (p<0.05) in newborns placed in oxyhood, using nasal CPAP and Mechanical Ventilation; oxygen saturation was the only parameter that did not alter significantly. We propose that nurses develop non-pharmacological interventions to reduce potential alterations caused in newborns’ physiological parameters due to this procedure.<br>Se objetivó investigar cuales son los parámetros fisiológicos que se alteran en la ejecución de la aspiración del tubo endotraqueal (TOT) y de las vías aéreas superiores (VAS), comparándolos inmediatamente antes, inmediatamente después y cinco minutos después de la realización del referido procedimiento. Se trata de un estudio cuantitativo, longitudinal, del tipo antes y después, realizado en una Unidad de Terapia Intensiva Neonatal (UTIN) de una institución pública en Fortaleza, CE, Brasil. La muestra constó de 104 recién nacidos que usaban oxigenoterapia, y que necesitaron de aspiración del tubo endotraqueal y de las vías aéreas superiores. Los resultados mostraron, alteraciones significativas (p<0,05) en las frecuencias respiratorias (FR) y cardíaca (FC) de los recién nacidos en uso de Oxi-Hood y CPAP nasal, y también del pulso (p<0,05) para los recién nacidos en Oxi-Hood, CPAP nasal y Ventilación Mecánica (VM), siendo la saturación de oxígeno (SpO2), el único parámetro que no fue estadísticamente significativo. Se propone a los enfermeros desarrollar intervenciones no farmacológicas para reducir posibles alteraciones de los parámetros fisiológicos de los recién nacidos provenientes de este procedimiento.<br>Objetivou-se investigar quais são os parâmetros fisiológicos que se alteram na execução da aspiração do tubo orotraqueal (TOT) e das vias aéreas superiores (VAS), comparando-os imediatamente antes, imediatamente depois e cinco minutos após a realização do referido procedimento. Trata-se de estudo quantitativo, longitudinal, do tipo antes e depois, realizado em Unidade de Terapia Intensiva Neonatal (Utin) de uma instituição pública em Fortaleza, CE, Brasil. A amostra constou de 104 recém-nascidos em uso de oxigenoterapia, e que necessitaram de aspiração do tubo orotraqueal e das vias aéreas superiores. Os resultados mostraram alterações significativas (p<0,05) nas frequências respiratória (FR) e cardíaca (FC) dos recém-nascidos, em uso de tenda de oxigênio (Oxi-Hood) e pressão contínua das vias aéreas (CPAP nasal), e também de pulso (p<0,05) para os recém-nascidos em Oxi-Hood, CPAP nasal e ventilação mecânica (VM), sendo a saturação de oxigênio (SpO2) o único parâmetro que não foi estatisticamente significante. Propõe-se aos profissionais enfermeiros o desenvolvimento de intervenções não farmacológicas para reduzir possíveis alterações dos parâmetros fisiológicos dos recém-nascidos, decorrentes desse procedimento

    Relação entre o consumo de açúcares de adição e a adequação da dieta de adolescentes residentes no município de São Paulo Relationship between the intake of added sugars and dietary adequacy in adolescents from the municipality of São Paulo, Brazil

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    OBJETIVO: Avaliar a relação entre o consumo de açúcares de adição e a adequação do consumo de nutrientes e grupos alimentares em adolescentes residentes no município de São Paulo. MÉTODOS: Foram avaliados 793 adolescentes, provenientes de um estudo de base populacional, realizado em 2003. O consumo alimentar foi medido pelo recordatório de 24 horas, tendo sido aplicado método de ajuste por meio de subamostra de 195 indivíduos. O consumo de açúcares foi categorizado em adequado ou inadequado, quando &#8804;10% ou >10% do valor energético total da dieta, respectivamente. A adequação de ingestão de macronutrientes considerou intervalos de distribuição aceitável, e a prevalência de inadequação dos micronutrientes foi calculada pelo método Estimated Average Requirement como ponto de corte. O consumo mediano dos alimentos foi estimado além dos percentis 25 e 75. Foram utilizados testes de Qui-quadrado, Wald e mediana, com nível de significância de 5%. RESULTADOS: Identificou-se maior proporção de adolescentes com consumo adequado de carboidratos entre aqueles com maior ingestão de açúcares de adição. Todos os adolescentes apresentaram ingestão proteica dentro dos valores preconizados e verificou-se associação significativa entre a adequação de lipídeos e o consumo de açúcares de adição somente entre os adolescentes do sexo masculino. Maior porção mediana de leite, carnes, frutas, suco industrializado, refrigerante e achocolatado em pó foi identificada entre os adolescentes com consumo excessivo de açúcares de adição. CONCLUSÃO: O consumo excessivo de açúcares de adição se mostrou relacionado à menor adequação do consumo de nutrientes e à menor ingestão de alimentos de alta densidade nutritiva.<br>OBJECTIVE: This study assessed the relationship between intake of added sugars and intake adequacy of nutrients and food groups in adolescents from São Paulo. METHODS: The study sample comprised 793 adolescents selected from a population-based cross-sectional study conducted in 2003. Food intake was assessed by 24-hour food recalls and an adjustment approach was subsequently administered using a subsample of 195 subjects. Sugar intake was considered appropriate or inappropriate when it represented &#8804;10% or >10% of total energy intake, respectively. Acceptable distribution ranges were used to assess macronutrient intake adequacy. The prevalence of micronutrient inadequacy was estimated using the Estimated Average Requirements as cutoffs. Median food intake and the 25th and 75th percentiles were estimated. The chi-square, Wald and median tests were used to analyze the data. The significance level was set at 5%. RESULTS: A larger proportion of adolescents with adequate carbohydrate intake were seen among those with higher added sugar intake. Protein intake by all adolescents was within the recommended ranges. A statistically significant association was found between adequacy of fat intake and added sugar intake among male adolescents. A higher median percent intake of milk, meat, fruit, processed juice, soft drink and chocolate milk was seen among adolescents with excess sugar intake. CONCLUSION: Excessive consumption of added sugars was associated with lower adequacy of nutrient intake and lower intake of nutrient-dense foods
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