Which variables influence compliance with physical activity recommendations in young children?

Introducción: Existen recomendaciones europeas de actividad física para la infancia. El principal objetivo de estudio era determinar los factores que podrían influir en el cumplimiento de las recomendaciones europeas de actividad física en la primera infancia. Métodos: Se incluyó a 136 niños (2-8 años), clasificados según su estado de peso medido con puntajes Z del IMC siguiendo los estándares de la Organización Mundial de la Salud. Se midió la actividad física durante 5 días consecutivos con acelerómetros y la ingesta diaria. Resultados: Una mayor actividad física se asoció con un menor estado de peso (B = −1,55; IC 95%: −2,02 a −1,08; p < 0,001), menor edad (B = −1,33; IC 95%: −1,72 a −0,93; p < 0,001) y mayor gasto energético (B = 0,02; IC 95%: 0,02 a 0,03; p < 0,001). El total de la muestra tuvo una actividad física ligera (media = 589 cpm/día). Los niños con sobrepeso y obesidad pasaron menos tiempo en actividad física moderada-vigorosa (p = 0,005) y más tiempo en actividad física sedentaria (p = 0,005) que los del grupo normopeso. Todos los grupos pasaron entre 90 y 130 min diarios en actividades sedentarias, con una media que supone un 15,5% del tiempo de actividad (eliminando las horas de sueño). El cumplimiento de las recomendaciones europeas depende del sexo (p = 0,010) y del estado de peso (p = 0,038). Conclusión: Los preescolares pasaron más de 100 min diarios en tiempo sedentario. Las recomendaciones europeas de actividad física moderada-vigorosa diarias se cumplieron por la mayoría de la muestra. Sin embargo, este cumplimiento dependía del sexo y del menor estado de peso.Introduction: There are established European guidelines for physical activity in childhood. The main goal of our study was to determine the factors that may influence compliance with European recommendations for physical activity in young children. Methods: We included 136 children (aged 2-8 years) classified by weight status, calculated based on the body mass index z-score using the growth standards of the World Health Organization. We measured physical activity over 5 consecutive days with accelerometers and recorded the food intake. Results: A greater level of physical activity was associated with a lower weight status category (B = −1.55; 95% CI: −2.02 to −1.08; P < .001), lower age (B = −1.33; 95% CI: −1.72 to −0.93; P < .001) and greater energy expenditure (B = 0.02; 95% CI: 0.02 to 0.03; P < .001). The overall physical activity in the sample was light (mean = 589 cpm/day). Children with overweight and obesity spent less time engaged in moderate to vigorous physical activity (P = .005) and more time engaged in sedentary activities (P = .005) compared to children with normal weight. All groups spent between 90 and 130 minutes a day in sedentary activities, with a mean time spent that amounted to 15.5% of their time (excluding time spent sleeping). The adherence to European recommendations varied in association with sex (P = .010) and weight status (P = .038). Conclusion: Young children spent more than 100 minutes a day engaged in sedentary activities. Most of the sample met the European recommendations for daily moderate to vigorous physical activity. However, the degree of adherence depended on sex and weight status

Demand and Storage Management in a Prosumer Nanogrid Based on Energy Forecasting

Energy efficiency and consumers' role in the energy system are among the strategic research topics in power systems these days. Smart grids (SG) and, specifically, microgrids, are key tools for these purposes. This paper presents a three-stage strategy for energy management in a prosumer nanogrid. Firstly, energy monitoring is performed and time-space compression is applied as a tool for forecasting energy resources and power quality (PQ) indices; secondly, demand is managed, taking advantage of smart appliances (SA) to reduce the electricity bill; finally, energy storage systems (ESS) are also managed to better match the forecasted generation of each prosumer. Results show how these strategies can be coordinated to contribute to energy management in the prosumer nanogrid. A simulation test is included, which proves how effectively the prosumers' power converters track the power setpoints obtained from the proposed strategy.Spanish Agencia Estatal de Investigacion ; Fondo Europeo de Desarrollo Regional

Energy management strategy to coordinate batteries and ultracapacitors of a hybrid energy storage system in a residential prosumer installation

Publicado en 2017 International Young Engineers Forum (YEF-ECE), Almada (Portugal), pp. 30-35, doi: 10.1109/YEF-ECE.2017.7935636En los últimos años, los sistemas de energía han experimentado un gran desarrollo como consecuencia de la aparición de la generación distribuida. Las fuentes de energía renovables, los usuarios activos y los vehículos eléctricos juegan un papel fundamental en los sistemas de energía, lo que supone un nuevo tema de investigación. En este escenario, la figura del prosumidor ha ganado relevancia debido a las múltiples ventajas que pueden aportar para mejorar el comportamiento de los sistemas de energía y lograr ahorros de energía y costos. En particular, se presta especial atención a los conjuntos fotovoltaicos (PV) integrados en edificios residenciales con sistemas de almacenamiento de energía (ESS), como baterías o ultracondensadores (UC) o incluso una combinación de ambos en un sistema de almacenamiento de energía híbrido (HESS). Este artículo presenta una estrategia de gestión de energía para intercambiar energía entre las baterías y las UC que forman un HESS instalado con una matriz FV en una vivienda de prosumidores para mantener su banco de UC disponible para satisfacer los requisitos de energía durante el mayor tiempo posible.In recent years, power systems have experimented a great development as a consequence of the apparition of the distributed generation. Renewable energy sources, active users and electric vehicles play a fundamental role in power systems, which has supposed a new topic research. In this scenario, the figure of prosumer has gained relevance due to the multiple advantages that they can contribute to improve the behavior of power systems and to achieve energy and cost savings. In particular, special attention is focus on photovoltaic (PV) arrays integrated in residential buildings with energy storage systems (ESSs), such as batteries or ultracapacitors (UCs) or even a combination of both in a hybrid energy storage system (HESS). This paper presents an energy management strategy to Exchange energy between the batteries and the UCs that form a HESS installed with a PV array in a prosumer dwell in order to maintain its UC bank available to support the energy requirements during the most time possible

Highest Plasma Phenylalanine Levels in (Very) Premature Infants on Intravenous Feeding; A Need for Concern

Objective. To analyse the association in newborns between blood levels of phenylalanine and feeding method and gestational age. Study Design. This observational, cross-sectional study included a sample of 11,829 infants between 2008 and 2013 in a Spanish region. Data were recorded on phenylalanine values, feeding method [breast, formula, mixed (breast plus formula), or partial or fully intravenous feeding], gestational age in weeks (<32, 32–37, ≥37), gender and days since birth at the moment of blood collection. Outcomes were [phenylalanine] and [phenylalanine] ≥95th percentile. Associations were analysed using multivariate models [linear (means difference) and logistic regression (adjusted odds ratios)]. Results. Higher phenylalanine values were associated with lower gestational age (p<0.001) and with intravenous feeding (p<0.001). Conclusion. The degree of prematurity and intravenous feeding influenced the plasma concentration of phenylalanine in the newborn. Caution should be taken in [phenylalanine] for newborns with intravenous feeding, monitoring them carefully. Very preterm infants given the recommended amount of amino acids should also be strictly monitored. These findings should be taken into consideration and call for adapting the amounts to the needs of the infant

Factors associated with moderate neonatal hyperthyrotropinemia

Background Maternal iodine deficiency is related to high neonatal thyroid-stimulating hormone (TSH) values, with the threshold of 5 mIU/L recommended as an indicator of iodine nutrition status. The objective of this study was to analyse possible risk factors for increased TSH that could distort its validity as a marker of iodine status. The clinical relevance of this research question is that if the factors associated with iodine deficiency are known, iodine supplementation can be introduced in risk groups, both during pregnancy and in newborns. Methods A case-control study was carried out in a sample of 46,622 newborns in 2002–2015 in Spain. Of these, 45,326 had a neonatal TSH value ≥5 mIU/L. The main variable was having TSH ≥5 mIU/L and the secondary variables were: sex, gestational age, day of sample extraction and maternal origin. Associated factors were analysed through a logistic regression model, calculating the odds ratio (OR). Results The factors associated with this outcome were: male sex (OR = 1.34, 95% CI: 1.20–1.50, p<0.001), originating from an Asian/Oceanic country (OR = 0.80, 95% CI: 0.54–1.20, p = 0.536) or Europe (OR = 0.80, 95% CI: 0.66–0.96, p = 0.285) (including Spain, OR = 1) [p<0.001 for America (OR = 0.54, 95% CI: 0.44–0.68) and p = 0.025 for Africa (OR = 0.78, 95% CI: 0.62–0.97)] and fewer days from birth to sampling (OR = 0.80, 95% CI: 0.77–0.82, p<0.001). Conclusions The risk of high neonatal TSH without congenital hypothyroidism is higher in males, decreases with a greater number of days from birth to extraction, and is dependent on maternal ethnicity but not on gestational age

The simplex method as a tool in the optimization of resources of an agroindustrial enterprise

El objetivo de la presente investigación es evaluar la asignación óptima de los recursos de una empresa agroindustrial dedicada a producción de nopal en salmuera en tres presentaciones, a través del método simplex de programación lineal usando la metodología de investigación de operaciones. Como herramienta tecnológica se utiliza el complemento Solver de la hoja de cálculo de Excel. El tema es relevante ya que, en México, se identifica alta mortandad de empresas en sus primeros años sobre todo en las micro y pequeñas, mientras que, las que permanecen en un mercado dinámico y competitivo manifiestan problemáticas con relación a la toma de decisiones que garantice una asignación eficiente de recursos. De los principales hallazgos destaca la construcción de un modelo matemático aplicando el método simplex para calcular el nivel de producción óptimo que minimice los costos de producción, resultando útil su aplicación para contribuir en la toma de decisiones de los empresarios.The objective of this research is to evaluate the optimal allocation of resources of an agroindustrial enterprise dedicated to the production of nopal in brine in three presentations, through the simplex method of linear programming using the operations research methodology. As a technological tool, the Solver complement of the Excel spreadsheet is used. The issue is relevant since, in Mexico, high mortality of companies is identified in their first years, especially in micro and small ones, while those that remain in a dynamic and competitive market manifest problems in relation to decision-making that ensure efficient allocation of resources. The main findings include the construction of a mathematical model applying the simplex method to calculate the optimal production level that minimizes production costs, its application being useful to contribute to the decision-making of entrepreneurs.O objetivo desta pesquisa é avaliar a alocação ótima de recursos de uma empresa agroindustrial dedicada à produção de nopal em salmoura em três apresentações, através do método simplex de programação linear utilizando a metodologia de pesquisa operacional. O suplemento Solver da planilha do Excel é usado como uma ferramenta tecnológica. O tema é relevante já que, no México, é identificada uma alta taxa de mortalidade de empresas em seus primeiros anos, especialmente em micro e pequenas empresas, enquanto aquelas que permanecem em um mercado dinâmico e competitivo apresentam problemas em relação à tomada de decisões para garantir uma alocação eficiente de recursos. As principais conclusões incluem a construção de um modelo matemático aplicando o método simplex para calcular o nível ideal de produção que minimiza os custos de produção, o que é útil para contribuir para o processo de tomada de decisão dos empreendedores

Determinación de grasa corporal en niños españoles de 2 a 7 años mediante diferentes fórmulas de plicometría y el índice cintura-talla

Introduction: It seems relevant to analyze the body composition in the early childhood. However, there is not an agreed in the protocol to assess body composition in this age range/group. Objective: To determine the most useful equation to estimate the body fat percentage that preschool children contain and the utility of the waist-to-height ratio to determine abdominal obesity. Methods: We measured (weight, height, waist circumference and skinfolds) 285 children aged 2 to 7 years old. BMI Z-Score, waist-to-height ratio and body fat percentage were estimated by Brook and Lukaski, Siri, Goran, Slaughter, Deurenberg, Huang, Dezenberg and Hoffman equations. Results: It was found that 26% combined overweight and obesity, with similar distribution in both sexes. Results: The body fat obtained with the Hoffman equation (15.6-31.9%) showed the highest correlation with children BMI Z-Score. Waist-to-height ratio also presented a good relationship with children weight status. There were not significant differences between gender and body fat percentage or waist-to-height ratio. Conclusions: The Hoffman equation and waist-to-height ratio could be adequate to estimate body fat percentage and abdominal obesity respectively in Spanish preschool children from medium-low socioeconomic status.Introducción: parece relevante analizar la composición corporal en la primera infancia. Sin embargo, en este rango de edad no existe un protocolo consensuado para determinar la composición corporal. Objetivo: determinar la fórmula más útil para estimar el porcentaje de grasa corporal contenido en niños preescolares y la utilidad del índice cintura-talla para determinar la obesidad abdominal. Métodos: medimos (peso, talla, circunferencia abdominal y pliegues cutáneos) a 285 niños de 2 a 7 años. Se estimaron el Z-Score de IMC, el índice cintura-talla y el porcentaje de grasa corporal mediante las fórmulas de Brook y Lukaski, Siri, Goran, Slaughter, Deurenberg, Huang, Dezenberg y Hoffman. Resultados: se halló un 26% de prevalencia combinada de sobrepeso y obesidad, con distribución similar entre sexos. El porcentaje de grasa corporal obtenido con la fórmula de Hoffman (15,6-31,9%) mostró la mayor correlación con el Z-Score del IMC. El índice cintura-talla también presentó una buena relación con el estado nutricional de los niños. No hubo diferencias significativas entre el sexo y el porcentaje de grasa corporal o el índice cintura-talla. Conclusiones: la fórmula de Hoffman y el índice cintura-talla podrían ser adecuados para estimar el porcentaje de grasa corporal y la obesidad abdominal respectivamente, en preescolares españoles de nivel socioeconómico medio-bajo

Impact of prematurity and immigration on neonatal screening for sickle cell disease

Background: Others have described a relationship between hemoglobin A levels and gestational age, gender and ethnicity. However, studies are needed to determine normal cut-off points considering these factors. To address this issue we designed a study to determine the percentiles of normality of neonatal hemoglobin A levels taking these factors into account. Methods: This cross-sectional study involved 16,025 samples for sickle cell disease screening in the province of Alicante, Spain, which has a high immigration rate. The primary variable was hemoglobin A, and the secondary variables were gender, gestational age (preterm and full term) and maternal origin (Spain, the rest of Europe, North Africa, Sub-Saharan Africa, Latin America and Asia). Percentiles of normality (1 and 99) were obtained by origin, gender and gestational age using quantile regression models and bootstrap samples. The association between these percentiles of normality and altered levels (≥1%) of hemoglobin E was analyzed. We obtained the percentiles of normality (1 and 99) for each maternal origin, gender and gestational age. Results: Of a total of 88 possible E carriers, 65 had above-normal hemoglobin A levels (74%). The levels of normality for hemoglobin A varied greatly according to the maternal origin and gestational age. Conclusion: With the levels of normality that we established it is possible to discard samples with unrecorded blood transfusions. Our methodology could be applied to other diseases in the neonatal screening

Árboles útiles del bosque tropical caducifolio secundario en la Reserva Forestal Villa Allende, Chiapas, México

Background and Aims: The tropical deciduous forest (TDF) stands out for its utilitarian value, although the information related to the use of plants by mestizo communities is limited. This research describes the use value and the ecological importance of native TDF secondary tree species near peasant communities in Villa Allende Forest Reserve, Chiapas, Mexico.   Methods: The ethnobotanical information was obtained via the free list technique complemented with a floristic inventory through the method of plots. The use value index was calculated as a measure of cultural importance and it was related to the ecological importance value of each useful species, using relative values of frequency, density and dominance. Key results: one hundred three useful angiosperm species were found, 77% of them are of multiple use and correspond to 10 categories in use, being the most remarkable: fuel (73), poles (68) and construction (63). Eysenhardtia adenostylis (1.36) and Acacia pennatula (1.29) were the species with the highest use value, although the majority (84%) registered low use values (≤0.3). Likewise, the species with the highest use value have low values of ecological importance (IVI ≤0.69). The use value per species was not related to the ecological importance value, except the dominance associated with the forest of 19 years of abandonment that correlated positively with the use value (rs=0.30, P=0.04) and the significant correlation between density and value of ornamental use (rs=0.41, P=0.03). Based on use value, nine potential species were recommended for conservation and restoration of TDF in the study area.Conclusions: The secondary TDF in Villa Allende Forest Reserve, Chiapas, provides useful tree species to satisfy the basic needs of the communities, although the cultural importance of these does not depend on its ecological importance.Antecedentes y Objetivos: El bosque tropical caducifolio (BTC) destaca por su valor utilitario, pero la información sobre el uso de las plantas por la población mestiza es limitada. Este estudio describe el valor de uso e importancia ecológica de las especies arbóreas nativas del BTC secundario cercano a comunidades campesinas en la Reserva Forestal Villa Allende, Chiapas, México.Métodos: La información etnobotánica se obtuvo por la técnica de lista libre y se complementó con un inventario florístico a través del método de parcelas. Se calculó el índice de valor de uso como medida de la importancia cultural y se relacionó con la importancia ecológica de cada especie útil, usando valores relativos de frecuencia, densidad y dominancia.Resultados clave: Se registraron 103 especies útiles de angiospermas, 77% de ellas son de uso múltiple y corresponden a 10 categorías de uso, siendo los más destacados: combustible (73), postes (68) y construcción (63). Eysenhardtia adenostylis (1.36) y Acacia pennatula (1.29) fueron las especies con el valor de uso más alto, aunque la mayoría (84%) registró bajos valores de uso (≤0.3). Asimismo, las especies con mayor valor de uso poseen bajos valores de importancia ecológica (IVI ≤0.69). El valor de uso por especie no se relacionó con el valor de importancia ecológica, excepto porque la dominancia del bosque de 19 años de abandono se correlacionó positivamente con el valor de uso (rs=0.30, P=0.04) y la relación significativa entre la densidad con el valor de uso ornamental (rs=0.41, P=0.03). Con base en el valor de uso se recomendaron nueve especies potenciales para conservación y restauración del BTC en la zona estudiada.Conclusiones: El BTC secundario en la Reserva Forestal Villa Allende, Chiapas, provee de especies arbóreas útiles para satisfacer las necesidades básicas de las comunidades, aunque la importancia cultural de éstas no depende de su importancia ecológica

Valores de actividad física en niños de dos a siete años, medidos mediante actimetría durante cinco días consecutivos las 24 horas diarias

Introduction: interpretation of accelerometer-derived physical activity in preschool children is confounded by differences in cut-off points. Aim: the purpose of this study was to analyze physical activity in 2-to-7-year-old children to establish reference values for daily activity. Methods: observational study in children aged 2-7 years, without chronic diseases and whose parents provided informed consent. The main variable was physical activity, measured continuously over 120 hours (three workdays and two weekend days) by accelerometer. Secondary variables were weight status (body mass index [BMI] Z-score) and gender. The relationship between the main variable and secondary variables was determined through the t-test, ANOVA and the Pearson correlation coefficient. A multivariate model was used to obtain the standard deviation (SD) of all possible combinations of values, constructing percentiles of normality (x ± SD and x ± 2·SD). Results: one hundred and thirty-six children (35% of municipality children) were included in the study (54.4% of them were girls). Their weight status distribution was: 25 underweight (18.4%), 54 normal weight (39.7%), 12 risk of overweight (8.8%), 22 overweight (16.2%) and 23 obese (16.8%). The median age was 5.7 years and the mean physical activity was 592 counts/minute. The boys undertook more physical activity (p = 0.031) and the underweight and normal-weight children undertook more physical activity than the overweight and obese children (p = 0.012). There were no significant differences according to age. The multivariate analysis showed significant differences (p < 0.001) according to gender and weight status. In boys, physical activity decreased as weight status increased. In contrast, the girls in the extreme BMI groups obtained higher levels of physical activity. Conclusion: overweight and obese preschool children had lower levels of physical activity than normal weight children. Physical activity levels were higher in boys.Introducción: la interpretación de la actividad física medida mediante actimetría en preescolares es confusa debido a los diferentes puntos de corte. Objetivo: el objetivo de este estudio fue analizar la actividad física en niños de dos a siete años para establecer valores de actividad física diaria. Método: estudio observacional en niños de dos a siete años, sin enfermedades crónicas y cuyos padres hubieran firmado el consentimiento informado. La variable principal fue la actividad física, medida durante 120 horas ininterrumpidas (tres días laborables y dos días festivos) mediante actímetros. Las variables secundarias fueron el estado de peso (puntaje z de índice de masa corporal [IMC]) y el sexo. La relación entre la variable principal y las variables secundarias fue determinada mediante el test-t, ANOVA y el coeficiente de correlación de Pearson. Se utilizó un modelo multivariable para obtener estándares de desviación en todas las posibles combinaciones de valores, construyendo percentiles de normalidad (x ± DE y x ± 2·DE). Resultados: participaron en el estudio 136 niños (35% de los niños del municipio); el 54,4% fueron chicas. La distribución de estado de peso fue: 25 niños con bajo peso (18,4%), 54 normopeso (39,7%), 12 en riesgo de sobrepeso (8,8%), 22 con sobrepeso (16,2%) y 23 con obesidad (16,8%). La media de edad fue 5,7 años y de actividad física, 592 cuentas/minuto. Los chicos realizaron mayor actividad física (p = 0,031) y los niños con bajo peso y normopeso realizaron mayor actividad física que los niños con sobrepeso y obesidad (p = 0,012). No hubo diferencias significativas respecto a la edad. El análisis multivariable mostró diferencias significativas (p < 0,001) respecto al sexo y el estado de peso. En los niños, la actividad física decreció cuando aumentó el peso. Por el contrario, las niñas en grupos de IMC extremos obtuvieron mayores niveles de actividad física. Conclusión: los preescolares en situación de sobrepeso y obesidad presentaron niveles menores de actividad física que los niños normopeso. Los niveles de actividad física fueron mayores en los chicos