Food from lunch packs (LP) or food available inside and outside of school can play an important role in the development of obesity. The purpose of this study was to evaluate the LP of elementary school (ES) and preschool children (PS) in Tijuana, and the foods available to them inside and outside of school. Eight public schools participated in the study. A random sample of all the groups from a school district was conducted. A questionnaire was administered to children in first through sixth grade (ES) and to the parents of PS. LP and food available inside and outside of the school were classified as healthy, unhealthy, and adequate according to the guidelines set forth by the Secretariat of Health. A total of 2,716 questionnaires were administered and the content of 648 LP was assessed. It was observed that 99% of PS had LP prepared at home, a higher percentage than ES. None of the LP of the ES was classified as healthy, and 1% was classified as adequate. Among PS, 21% of the LP were classified as healthy and 6% as adequate. More than half of the children recognized the brand name of foods high in fat, salt, and added sugar available inside and outside of school grounds. Most of the LP of ES and PS and the foods available inside and outside of school were unhealthy and inadequate. A strategy to prevent the availability of unhealthy and inadequate food in LP and foods available inside and outside schools is recommended.

Here we use finite element analysis to determine the suitability of basalt fiber as a substitute for E-glass in structural applications, which would improve the cost effectiveness of small wind turbine blades. Five NACA (National Advisory Committee for Aeronautics) profiles were evaluated to select the optimum shape for the wind operation conditions. To obtain the wind load pressure distribution over the blade, a computational aerodynamic analysis by CFD (computational fluid dynamics) was performed based on the blade’s design and operating conditions. Material properties and mechanical tests were carried out to obtain the fiber volume fraction, density, Young’s modulus, shear modulus, and Poisson relation of polymeric matrix composites made using basalt and fiberglass. The obtained wind loads and material properties were used on a FEM (finite element model) analysis to evaluate the structural behavior of the blade under normal and critical operating conditions. Both fibers meet the structural requirements under normal operating conditions. We detected a reduction of 4% in the blade stress when basalt fibers are used instead of glass fibers, and a reduction of 68% in the total deformation for a critical load case of 40 m/s was obtained when using basalt fibers, which met the structural requirements and maximum power generation required for this wind turbine design.

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