THE INFLUENCE OF INDIVIDUAL MUSCLE GROUPS ON FEMORAL STRAIN DISTRIBUTION DURING WALKING

INTRODUCTION Mechanical strain resulting from muscle forces in locomotion plays an important role in the maintenance of bone health [1]. Depending on their magnitude and line of action, these muscle forces may lead to an overall increase or decrease in mechanical strain [2]. Thus, the exclusion of specific muscle groups in finite element models may have a significant impact of simulation results. Our purpose was to quantify the influence of individual muscle groups on the femoral strain distribution during walking using the finite element method. METHODS Kinematic and kinetic data were collected from ten males (age 24.9 ± 4.7 yrs; height 1.7 ± 0.1 m; mass 70.1 ± 8.9 kg) walking overground at 1.25 and 1.75 m/s. Joint reaction forces and moments were calculated using standard inverse dynamics procedures. Muscle and hip contact forces were quantified using musculoskeletal modeling [3] with a static optimization routine (cost function = sum of squared muscle stresses) [4]. For both walking speeds, two instances in stance were examined in the finite element models, coinciding with the first (Peak 1) and second peak (Peak 2) of the axial hip contact force. A finite element model of a young, healthy femur was generated from the VAHKUM database (http://www.ulb.ac.be/project/vakhum/) and scaled to average subject size. Bone was assigned inhomogeneous linear-elastic material properties based on apparent density [5]. The femur was physiologically constrained at the lateral epicondyle, center of the patellar groove, and femoral contact point [6]. Muscle and hip contact forces were applied as point loads. Seven different simulations were run in ABAQUS Standard v6.1 (Providence, RI) for each of the two instances in stance at both 1.25 and 1.75 m/s. For baseline analyses, all the muscle loads were included. For subsequent analyses, muscles forces from specific muscle groups (Hip Adductors, Hip Abductors, Hip Flexors, Hip Extensors, Hip Internal Rotators, and Hip External Rotators) were orderly removed.  Principal strains were quantified along the anterior, lateral, medial, and posterior aspects of the femoral periosteal surface. RESULTS & DISCUSSIONS For all simulations, principal compressive and tensile strains were greatest on the medial and lateral aspect of the femur, respectively (Figure 1). Strain magnitudes for baseline analyses were consistent with in vivo measurements [7], ranging from 1,500-2,000 με and increasing with walking speed. Strains were higher during Peak 1, compared to Peak 2, and removal of specific muscle groups had a greater influence on the strain distribution at this instance in stance. Removal of the hip extensors, abductors, and internal rotators resulted in an overall increase in the femoral strain distribution (Figure 1), suggesting these muscles have a prophylactic action to reduce femoral bending. On the other hand, removal of the hip flexors, adductors, and external rotators had a negligible effect of the femoral strain distribution (Figure 1), but these muscles were minimally activated during walking. CONCLUSIONS Specific muscle groups make important contributions to the femoral strain distribution during walking, and failure to include these muscles in finite element models will lead to erroneous conclusions regarding femoral strain magnitudes

Use of m-Health Technology for Preventive Interventions to Tackle Cardiometabolic Conditions and Other Non-Communicable Diseases in Latin America- Challenges and Opportunities

In Latin America, cardiovascular disease (CVD) mortality rates will increase by an estimated 145% from 1990 to 2020. Several challenges related to social strains, inadequate public health infrastructure, and underfinanced healthcare systems make cardiometabolic conditions and non-communicable diseases (NCDs) difficult to prevent and control. On the other hand, the region has high mobile phone coverage, making mobile health (mHealth) particularly attractive to complement and improve strategies toward prevention and control of these conditions in low- and middle-income countries. In this article, we describe the experiences of three Centers of Excellence for prevention and control of NCDs sponsored by the National Heart, Lung, and Blood Institute with mHealth interventions to address cardiometabolic conditions and other NCDs in Argentina, Guatemala, and Peru. The nine studies described involved the design and implementation of complex interventions targeting providers, patients and the public. The rationale, design of the interventions, and evaluation of processes and outcomes of each of these studies are described, together with barriers and enabling factors associated with their implementation.Fil: Beratarrechea, Andrea Gabriela. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Diez Canseco, Francisco. Universidad Peruana Cayetano Heredia; PerúFil: Irazola, Vilma. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miranda, Jaime. Universidad Peruana Cayetano Heredia; PerúFil: Ramirez Zea, Manuel. Institute of Nutrition of Central America and Panama; GuatemalaFil: Rubinstein, Adolfo Luis. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Nanocrystalline cathodes for PC-SOFCs based on BCZY

Perovskites based on BaCeO3-δ exhibit the highest proton conductivity among this class of materials, however, they are susceptible to hydration and carbonation in presence of water vapor and CO2 [1]. In contrast, the chemical stability of BaZrO3-based protonic conductors is better, but they require sintering temperatures as high as 1700 ºC and suffer from high intrinsic grain boundary resistance, limiting the final performance. Partial substitution of Zr for Ce in Ba(Ce0.9-xZrx)Y0.2O3-δ allows obtaining electrolytes with both high proton conductivity and good chemical stability. The performance of a PC-SOFC at low temperatures depends significantly on the ohmic resistance of the electrolyte, although it can be lowered by reducing the electrolyte thickness. Another important limiting factor is the increase of the cathode polarization resistance due to the thermally activated nature of the oxygen reduction reaction. For this reason, it is essential to obtain high efficiency cathodes operating at reduced temperatures. In this work, BaCe0.6Zr0.2Y0.2O3-δ (BCZY) powders were prepared by freeze-drying precursor method. These powders were mixed with a Zn-containing solution as sintering additive in order to obtain dense pellets with submicrometric grain size at only 1200 ºC. After that, La0.6Sr0.4Co0.8Fe0.2O3 nanocrystalline electrodes were deposited symmetrically onto dense pellets BCZY by conventional spray-pyrolysis [3]. The structure, microstructure and electrochemical properties of these electrodes have been examined by XRD, FE-SEM and impedance spectroscopy. The stability of these electrodes at intermediate temperatures was evaluated as a function of time. These nanocrystalline cathodes exhibit a substantial improvement of the electrode polarization resistance with respect to the same materials prepared by screen-printing method at high sintering temperatures, e.g. 0.7 and 3.2 cm2 at 600 ºC for LSCF cathodes prepared by spray-pyrolysis and screen-printing method respectively (Figure). An anode supported cell with composition LSCF/BCZY/NiO-BCZY was also prepared to test the electrochemical performance.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Diseño de una propuesta de laboratorio móvil para el ¨programa piloto para el desarrollo local a partir de la gestión del conocimiento en laboratorios de innovación : capacidades en diseño, tecnología e innovación en 7 municipios de Boyacá¨

1 recurso en línea (135 páginas) : ilustraciones color, tablas.El presente proyecto desarrolló una propuesta de laboratorio móvil de innovación y co-creación, el cual servirá de herramienta estratégica para acercar las provincias y poblaciones rurales al mundo de la innovación y la tecnología, para incluirlas en las dinámicas globales, Con el propósito de darle solución a la escasa innovación y gestión del conocimiento que existe actualmente en los municipios que son prominentemente rurales. Se usaron diferentes herramientas metodológicas enfocadas en el usuario, en las que se tomaron en cuenta sus características personales y sociales, así como aquellas condiciones relevantes para los fenómenos de percepción, comunicación y significancia. Esta herramienta permitirá configurar ambientes favorables de manera didáctica e inspiradora para desarrollar el pensamiento estratégico de las poblaciones en estos municipios. Con este laboratorio móvil se busca acercar el diseño y los negocios innovadores a las poblaciones que tiene limitaciones de acceso a la educación en tecnología y generar diferentes oportunidades para pensar su futuro, identificando oportunidades de emprendimiento que puedan impactar su cotidianidad, y generar arraigo por los territorios y recursos propios de cada municipio.Bibliografía y webgrafía: páginas 93-94PregradoDiseñador Industria

Caracterización de las prácticas de marketing relacional llevadas a cabo por las agencias y agentes de seguros en la ciudad de Medellín

Maestría en Mercadeo, Facultad de Ciencias Contables, Económicas y Administrativas.El marketing de relaciones es una práctica que hoy está siendo muy utilizada por organizaciones de toda índole alrededor del globo, debido a que contribuye enormemente al manejo administrativo de su área comercial. Y más que una actividad y una técnica de negocios, es una “actitud” que la empresa o empresario desarrolla en favor de mejorar las acciones con sus clientes con el fin de obtener provecho de ello. Esto último quiere decir que desde que una empresa se dispone a trazar su planeación estratégica para conducir su negocio, la conciencia y decisión de sus directivos debe estar enfocada en la orientación hacia el cliente y sus aliados de negocios para garantizar la perdurabilidad de la empresa en el mercado y su mejor posición al enfrentar las condiciones adversas que este le presenta, especialmente la competencia, porque ésta no se quedará de manos cruzadas y buscará también dominar el mercado en disputa. El insumo básico para poder practicar un Marketing de Relaciones altamente efectivo es la información que la empresa va acumulando a lo largo de toda una vida de relaciones comerciales con sus clientes en sus diferentes etapas de maduración. Lo mismo puede decirse de sus aliados estratégicos; construye relaciones con ellos para actuar como “un todo” en la oferta de servicio hacia el cliente

Inteligencia emocional y hábitos de estudio en estudiantes del primer ciclo del Instituto Superior Tecnológico Khipu de la ciudad del Cusco, 2015

El presente estudio se realizó en estudiantes del primer ciclo que concurren al Instituto Superior Tecnológico “Khipu” de la ciudad del Cusco, se realiza con el objetivo de conocer la relación existente entre las variables, objetos del presente estudio, que son la inteligencia emocional y los hábitos de estudio, en función a los resultados obtenidos, los datos servirán de aporte y serán de gran ayuda a la institución. El tipo y diseño de investigación empleado es el descriptivo correlacional. La población está constituida por todos los estudiantes del primer ciclo del Instituto Superior Tecnológico “Khipu” de Cusco, en el semestre de estudios 2015 – I que vienen a ser un total de 775 alumnos en los turnos de la mañana, tarde y noche y con una muestra de 193 estudiantes, a quienes se les aplicó el inventario de inteligencia emocional de BarOn Ice y el inventario de hábitos de estudio CASM – 85. Se identificó el nivel de inteligencia emocional así como también la categoría predominante de los hábitos de estudio en los estudiantes. Entre los resultados se halla una relación positiva entre la inteligencia emocional y los hábitos de estudio, así mismo se puede ver que el nivel de inteligencia emocional que presentan en su mayoría es el promedio y la categoría que predomina en los hábitos de estudio es la tendencia negativa.Universidad Nacional de Educación Enrique Guzmán y Valle.Tesi

Activities contributing to energy expenditure among Guatemalan adults

<p>Abstract</p> <p>Background</p> <p>Guatemala has experienced a substantial increase in overweight and obesity in recent years, yet physical activity patterns and consequent energy expenditure are largely unexplored in this population.</p> <p>Methods</p> <p>To describe overall physical activity levels (PAL) and activities contributing to daily energy expenditure, we analyzed time spent in daily activities as reported by 985 women and 819 men, living in rural and urban areas of Guatemala in 2002–04.</p> <p>Results</p> <p>Physical activity levels recommended to prevent obesity (PAL ≥ 1.70) differed by residence/occupation among men (agricultural-rural: 77%; nonagricultural-rural: 36%; urban: 24%; P < 0.01), but not women (rural: 2%; urban: 3%; P = 0.5). Median energy expenditure was higher among agricultural-rural men (44 MET*h/d; MET = metabolic equivalent) compared to nonagricultural-rural (37 MET*h/d) and urban men (35 MET*h/d; P < 0.01); energy expenditure was slightly lower among rural compared to urban women (34 MET*h/d vs. 35 MET*h/d; P < 0.01). Occupation was the largest contributor to energy expenditure (19–24 MET*h/d); among women and nonagricultural-rural and urban men this was primarily of a light intensity. Energy expenditure in sedentary activities ranged from 2 MET*h/d among rural women to 6 MET*h/d among agricultural-rural men. Any sports/exercise time was reported by 35% and 5% of men and women, respectively. Nevertheless, the majority of participants believed they were significantly active to stay healthy.</p> <p>Conclusion</p> <p>Overall, energy expenditure was low in the population not dedicated to agricultural occupations; an increased focus on active leisure-time behaviors may be needed to counterbalance reductions in energy expenditure consequent to sedentarization of primary occupations.</p

What determines adult cognitive skills?: Impacts of preschooling, schooling, and post-schooling experiences in Guatemala

"Most investigations into the importance and determinants of adult cognitive skills assume that (1) they are produced primarily by schooling, and (2) schooling is statistically predetermined or exogenous. This study uses longitudinal data collected in Guatemala over 35 years to investigate production functions for adult cognitive skills—that is, reading-comprehension skills and nonverbal cognitive skills—as being dependent on behaviorally determined preschooling, schooling, and post-schooling experiences. We use an indicator of whether the child was stunted (child height-for-age Z-scoreHuman capital, cognitive skills, Stunting, work experience, Development, Education, Gender, Health and nutrition,

The consequences of early childhood growth failure over the life course:

This paper examines the impact over the life course of early childhood growth failure as measured by achieved height at 36 months. It uses data collected on individuals who participated in a nutritional supplementation trial between 1969 and 1977 in rural Guatemala and who were subsequently reinterviewed between 2002 and 2004. It finds that individuals who did not suffer growth failure in the first three years of life complete more schooling, score higher on tests of cognitive skill in adulthood, have better outcomes in the marriage market, earn higher wages and are more likely to be employed in higher-paying skilled labor and white-collar jobs, are less likely to live in poor households, and, for women, fewer pregnancies and smaller risk of miscarriages and stillbirths. Growth failure has adverse impacts on body size and several dimensions of physical fitness in adulthood but does not have marked effects on risk indicators of cardiovascular and related chronic diseases. These results provide a powerful rationale for investments that reduce early-life growth failure.Chronic disease, early life growth failure, fertility, Human capital, Poverty, Undernutrition, Wages,