The kinematics of the swing phase obtained from accelerometer and gyroscope measurements

The kinematics needed to calculate the knee moment during the initial swing phase were obtained from a set of eight leg-mounted uni-axial accelerometers and two gyroscopes. The angular and linear accelerations of shank and thigh were calculated from the signals of two accelerometers mounted on each of the leg segments directed tangentially and radially to the movement. The angular velocities of shank and thigh were measured by the gyroscopes. The absolute angles of shank and thigh were obtained by integration of the gyroscope signal plus an added offset angle, estimated from radial and tangential accelerometer signals registered while standing. Movement was assumed to be in the saggital plane. The accuracy of the quantities found from the leg mounted sensors was calculated in terms of correlation and the RMS error by comparing against measurements obtained by a VICONTM system. The results were indistinguishable. The system was later applied in research measurement

Influencer marketing and health repercussions: a literature review on the impact of influencers on eating behavior and body self-perception

The aim of this article is to review the scientific literature regarding the impact of influencer marketing on eating habits and the development of attitudes related to body cult. For this purpose, the authors conducted a systematic review to identify empirical articles focused on Influencer Marketing strategies related to food or body cult published within the last 10 years. Using specific keywords, 80 articles were retrieved from PubMed, Scopus, and WoS databases. Finally, a content analysis of 34 selected articles was performed. The findings show that the most common objective of these studies was to examine the characteristics of influencers in terms of message effectiveness, followed by assessing the impact of influencers on eating behaviours. Regarding study results among influencer marketing strategies on eating habits, no article included positive conclusions on influencer marketing and food

Evolución del fitoplancton en el Parque Nacional de las Tablas de Daimiel (Ciudad Real, 1996-2002)

El Parque Nacional de Las Tablas de Daimiel (PNTD) es un humedal semiárido situado en la Llanura Manchega (Ciudad Real). En este artículo se expone la dinámica del fitoplancton desde 1996 hasta 2002, examinando las continuidades y divergencias que se observan en el espacio y el tiempo. Tres puntos del humedal (PG: entrada al Parque; MM y PN: salida en zona media y final) se muestrearon mensualmente desde Marzo 1996 a Diciembre 2002. El biovolumen total del fitoplancton del PNTD fue muy variable tanto en el tiempo como en el espacio, el valor mínimo y el máximo se presentaron en PG (0.06 mm3/l en mayo de 1996, y 775 mm3/l en septiembre de 2001). Se observa un marcado incremento del promedio de biovolumen de todo el humedal a lo largo del tiempo, de 11 ± 3 mm3/l en 1996 a 40 ± 9 mm3/l en 2002. La contribución relativa de los grupos taxonómicos al biovolumen total de fitoplancton mostró también cambios a corto y largo plazo, y fueron distintos en cada una de las tablas muestreadas. Hemos encontrado algunas especies de algas que son indicadoras de cierto grado de salinidad en el agua, ellas son: Chaetoceros muelleri, Urosolenia sp. y Katodinium fungiforme. Así como un aumento en el número de especies y densidad de las euglenofitas. Esta larga serie de datos nos permite extraer una serie de conclusiones sobre el funcionamiento de los productores primarios planctónicos en un humedal somero: a) a la escala espacial de todo el humedal el biovolumen de fitoplancton responde al clima local; b) la tendencia de eutrofización es claramente detectada en todo el humedal; c) las fluctuaciones hidrológicas provocan variaciones a corto plazo, permitiendo una serie continua de estados alternantes y no cíclicos de la comunidad; d) la heterogeneidad espacial de este sistema de islas y tablazos permite una amplia riqueza en el conjunto del humedal.Las Tablas de Daimiel National Park (TDNP) is a wetland located in La Mancha Plain (Ciudad Real, Central Spain). Our study reports 1996-2002 phytoplankton dynamics, examining spatio-temporal patterns of continuity and divergence. Three wetland sites (PG-main inlet, MM and PN-main outlets) were sampled monthly from March 1996 to December, 2002. Overall phytoplankton biovolume were very variable in space and time. Extreme values occurred in PG in May, 1996 (0.06 mm3/l) and September, 2001 (775 mm3/l). Average values of phytoplankton biovolume experienced aa marked increment over timefrom 11±3 mm3/l in 1996 () to 40±9 mm3/l in 2002. The relative contribution to the total biovolume of the taxonomic groups also showed short and long-term changes and they were different in each of the sampled sites. Some species indicating increasing salinity, such as Chaetoceros muelleri, Urosolenia sp. and Katodinium fungiforme, were recorded. Species numbers and density of euglenoids increased as well. This long-term dataset enabled us to draw some conclusions over planktonic primary producers functioning in a shallow wetland: a) at the wetland scale phytoplankton biovolum responds to local climate, b) a eutrophication trend is clearly detected in the whole wetland, c) hydrologic fluctuations are responsible for a short-term variability, thus allowing a variety of non-cyclic assemblage' s alternate states, d) spatial heterogeneity arising from the distribution of water tables and islands results in a remarkable species richness at the wetland scale

Vivienda net-zero en Mexicali, B.C, un camino hacia las políticas energéticas en desarrollos habitacionales sustentables

En México, la energía es considerada una de las actividades económicas más importantes; además de constituir la fuente principal del ingreso público. El sector energético contribuye al PIB en un 3%; las exportaciones petroleras representan el 8.4% del total nacional y los impuestos de los hidrocarburos aportan el 37% de los ingresos fiscales. En esta investigación, se realizó una evaluación térmica de dos viviendas ubicadas en Mexicali, B.C.; una denominada caso base y otra Net-Zero. La primera es la vivienda con el sistema constructivo tal y como el desarrollador la entrega, y la segunda, es una vivienda a la cual se le aplicaron los sistemas de aislamientos propuesto por Norma 460 de eficiencia energética mexicana (NMX-460), además de los electrodomésticos de alta eficiencia, focos ahorradores y sistemas de aire acondicionado EER 13. Las viviendas evaluadas son de interés medio alto, con una superficie aproximada de 137 m2; los objetivos generales de esta investigación se centraron en reducir la vivienda caso base con un consumo eléctrico anual de 15,000 kWh a una línea base de consumo mínima (Net-Zero) de 8000 kWh, consumo que permitirá diseñar un sistema fotovoltaico que servirá para autoabastecer a la propia vivienda; aunado a esto, el programa REEP (Renewable Energy Efficiency Program), fondo canadiense se involucró en la financiación del programa piloto de monitoreo de vivienda Net-Zero, sumándose a este esfuerzo la CONAVI (Comisión Nacional de Vivienda) y apoyando con la validación y factibilidad de dicho proyecto en la parte técnica-operativa la CFE (Comisión Federal de Electricidad) subdivisión Mexicali. Los resultados mostraron que la vivienda Net-Zero es posible desarrollarla bajo el contexto Mexicano, con el sentido de generar políticas energéticas que direccionen desde la construcción del sistema físico, las tecnologías aplicadas, los electrodomésticos utilizados, los sistemas de aire acondicionado eficientes, el patrón de uso de la misma, así como las características de la energía fotovoltaica y sus técnicas de aplicación, tanto de interconexión a la red como los sistemas de medidores bidireccionales aplicados a este tipo de sistemas. Finalmente, la investigación muestra el costo beneficio y el retorno de inversión de un sistema fotovoltaico aplicado a una vivienda con estas características.In Mexico, energy is considered one of the most important economic activities; besides constituting the main source of public inputs, the power sector contributes the PIB in a 3%; petroleum exports represent the 8 4% of the national total and the hydrocarbon taxes contribute 37% of the fiscal income. In this investigation, a thermal evaluation of two houses located in Mexicali, B.C. was made; one denominated as case base and the other as Net-Zero. First we have the house with the constructive system as the developer delivers it and the second, is a house to which insulation systems were applied, proposed by Mexican energy efficiency norm 460 (NMX-460), besides the electric home appliances of high efficiency, saving and air conditioned systems EER 14. The evaluated dwellings are medium high interest, with an approximated surface of 137 m2, the general purpose of this research consists in reducing the dwelling case base with an annual electrical consumption of 15.000 kWh to a minimum consumption (Net-Zero) of 8000 kWh, allowing to design a photovoltaic system that will serve to self supply the house; combined to this, REEP (Renewable Energy Efficiency Program) Canadian funds, that became involved in the financed test monitoring program of Net-Zero dwelling, included to this effort the CONAVI (National Commission of Dwelling) and supported with the validation and feasibility of this project in the technique-operative part by CFE (Federal Commission of Electricity) Mexicali’s subdivision. The results showed that it is possible to develop the Net-Zero house under a Mexican context, with the intention of generating energetic policies that conduct the construction of the physical system, the applied technologies, the used electric home appliances, the efficient air conditioned systems, the factor use, the characteristics of photovoltaic energy and their technicians meaning the ones in charge of interconnection to the network like the systems of bidirectional measurers applied to this type of systems. Finally the research shows the cost benefit and the reinvestment applying photovoltaic systems to a house with these characteristics and the energy policies that must be considered.Peer Reviewe