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Aluminum is a heavy metal toxic to living organisms and is released into soils with a strong acidic composition. The floating aquatic weed Eichhornia crassipes (Mart.) Solms is reported as the most widespread invasive vascular plant in the world and is distributed all over Colombia ranging from sea level to the cold Andean highlands. As a consequence of the solubility of Al3+ in soils, it flows into fresh water sources where E. crassipes grows as an invasive plant. A greenhouse study was conducted in Tunja, Colombia, with the objective of evaluating the growth of aquatic weed in an aqueous substrate with Al3+ content similar to those recorded in lakes (0.0, 0.2, 0.4, 0.6, and 0.8 mg L-1 Al3+). Biomass production, leaf area, evapotranspiration, water use efficiency, and other allometric variables were evaluated. An increase of 18.2% in the transpiration rate and a reduction between 9.7%-41.8% in the leaf area were found. The latter reduced the value of variables such as the specific leaf area between 9.9%-34.6% and leaf area ratio between 16.7%-40.4%. However, the total dry weight, DM partitioning, root to shoot ratio, leaf weight ratio, and the absolute and relative growth rates did not show significantly different values between treatments. Therefore, Al content found in water sources in Colombia, despite being in the ranges reported as toxic for some aquatic plants, did not significantly affect the growth of E. crassipes due to its phenotypic plasticity and anthropic alteration of water sources but rather favor its growth.

Summary This study developed a well-standardized and reproducible approach for micro-finite element (mFE) and homogenized-FE (hFE) analyses that can accurately predict the distal radius failure load using either mFE or hFE models when using the approaches and parameters developed in this study. Introduction Micro-FE analyses based on high-resolution peripheral quantitative CT (HR-pQCT) images are frequently used to predict distal radius failure load. With the introduction of a second-generation HR-pQCT device, however, the default modelling approach no longer provides accurate results. The aim of this study was to develop a well-standardized and reproducible approach for mFE and hFE analyses that can provide precise and accurate results for distal radius failure load predictions based on second-generation HR-pQCT images. Methods Second-generation HR-pQCT was used to scan the distal 20-mm section of 22 cadaver radii. The sections were excised and mechanically tested afterwards. For these sections, mFE and hFE models were made that were used to identify required material parameters by comparing predicted and measured results. Using these parameters, the models were cropped to represent the 10-mm region recommended for clinical studies to test their performance for failure load prediction. Results After identification of material parameters, the measured failure load of the 20-mm segments was in good agreement with the results of mFE models (R2 = 0.969, slope = 1.035) and hFE models (R2 = 0.966, slope = 0.890). When the models were restricted to the clinical region, mFE still accurately predicted the measured failure load (R2 = 0.955, slope = 1.021), while hFE predictions were precise but tended to overpredict the failure load (R2 = 0.952, slope = 0.780). Conclusions It was concluded that it is possible to accurately predict the distal radius failure load using either mFE or hFE models when using the approaches and parameters developed in this study. Electronic supplementary material The online version of this article (10.1007/s00198-019-04935-6) contains supplementary material, which is available to authorized users.

Los negocios inclusivos son una tendencia empresarial que vincula los miembros de una sociedad y mejora la calidad de vida de las personas, mediante la posibilidad de formar parte activa de cadenas productivas como proveedores de bienes y servicios o consumidores, lo que permite agregar valor a las empresas. El ámbito de la educación superior se ha venido preocupando por generar espacios que permitan la creación de iniciativas con esta visión, motivo del presente artículo. El presente escrito pretende identificar si los estudiantes de las facultades de ciencias administrativas en cuatro universidades del país podrían generar negocios inclusivos, por medio del aprendizaje adquirido en sus programas académicos virtuales. Para la investigación se utilizó una metodología con enfoque cuantitativo, por medio de la aplicación de una encuesta con tendencia probabilística a 359 estudiantes, con 1-α=95% y e=+/-6,9, por medio de un alcance descriptivo y un diseño no experimental. Los resultados muestran que las cuatro instituciones se esfuerzan por promover el emprendimiento y la inclusión como una tarea de responsabilidad social, pero deben fortalecer las herramientas y metodologías pedagógicas para este fin, así como incluir el tema de negocios inclusivos como parte de sus currículos. Para futuros estudios se considera pertinente comparar casos de éxito de generación de negocios que se consideren inclusivos.

ResumenObjetivoConocer las características de la población en riesgo de tromboembolia venosa y determinar si la profilaxis antitrombótica usada en patologías no quirúrgicas en un hospital universitario de tercer nivel, se adhiere a los protocolos de tromboprofilaxis establecidos.MétodosSe llevó a cabo un estudio observacional de corte transversal, en el que se incluyeron pacientes mayores de 40 años, hospitalizados por patologías de tratamiento médico no quirúrgicas y con una permanencia de por lo menos 72 horas. Para evaluar el riesgo de trombembolia venosa y de sangrado se aplicaron las escalas PADUA e IMPROVE, respectivamente.ResultadosLa muestra estuvo conformada por 233 pacientes, 56,6% del género masculino, con promedio de edad de 64,8 años ± 13,1. La inmovilidad prolongada fue el principal factor de riesgo para trombembolia venosa durante la hospitalización; ésta fue cercana al 48,9% en la muestra total y a 69,4% en los pacientes evaluados mediante la escala de PADUA ≥4 (p

One of the benefits that the signing of the North American Free Trade Agreement (NAFTA) would bring to the country was the reduction of large differences in wages as a result of the increase in productivity. The present study measures the effect of demographic, labor, and sector variables on Mexico?s wage inequality during the period 1988 to 2017, as well as the impact that the incorporation to NAFTA has had. Through a fixed effects model, it was found that the increase in the proportion of people working in the service and agricultural sectors increased the wage gap, as well as the people who occupy managerial positions, since they obtained a relative salary higher than the average. Despite the expected results of NAFTA, this economic trade integration increased the wage differential in Mexico and these levels are invariant over time, giving way to proposals to change the minimum wage.

Mechanical analysis of animal long bones often makes use of beam theory to estimate tissue properties from bending tests. An earlier study (van Lenthe et al., 2008) found that beam theory leads to a considerable underestimation of the Young's modulus of mice femora. However, we hypothesized that beam theory might still be an accurate tool for the determination of bone strength from experimental data. The first goal was to test this hypothesis, along with checking if the underestimation of the tissue modulus is also valid for rat femurs. The second goal was to investigate if micro-FE and beam theory would yield similar increases in Young's moduli and yield stress during aging. Twelve rat femurs (12 and 16 weeks old) were scanned using micro-CT and subjected to a three-point bending test from which the bending stiffness and the yield force were obtained. The Young's modulus and yield stress then were calculated by regressing the experimental results with results obtained from beam theory and micro-FE analysis based on the micro-CT scans. It was found that bone strength calculated using beam theory overestimated that calculated from micro-FE by 8.0%. The Young's modulus did not significantly differ. When comparing age groups, similar increases in tissue modulus and yield strength were found for beam theory and micro-FE, with significant differences only for the micro-FE yield stress. We concluded that the use of beam theory to calculate bone yield strength from 3-point bending test results of rat femurs leads to its overprediction.

Resumen En esta investigación se establece una metodología que permite describir el movimiento de miembros inferiores usando cadenas cinemáticas cerradas. Este análisis es realizado con el objetivo de determinar la posición del centro de rotación (CR) de la rodilla localizado en el plano sagital. Un paciente sano y sin antecedentes patológicos realizó pruebas de flexión-extensión con uno de sus miembros inferiores. Cuando el paciente realizo el movimiento articular (la flexo-extensión) un dispositivo de video y un programa (World In motion v4.0) determinan la posición de cuatro marcadores pasivos ubicados en el miembro inferior. Los datos obtenidos de los marcadores son utilizados en un modelo propuesto que permite localizar la posición del CR de la rodilla. En este estudio se concluye que el CR de la rodilla presenta movimiento relativo respecto a un punto fijo marcado en un miembro inferior. Los resultados comprueban que el CR de la rodilla delimitado en el plano sagital no presenta comportamiento de una junta completa (junta con un grado de libertad) como ha sido presentado en otros estudios. Abstract A methodology is established in this research which permits to describe the movement of a lower limb using closed kinematic chains. This analysis is developed with the aim to determine the location of the center of rotation (CR) of the knee joint in the sagittal plane. Flexion-extension tests were carried out on one of the lower limbs of a healthy patient without pathological antecedents. When the patient does articular movement (flexion-extension), a video equipment and a software determine the position of four passive markers installed on the lower limb. The information obtained from the markers is applied to the proposed model which allows to locate the center of rotation of the knee joint. Hence it was concluded that the CR of the knee joint undergoes a relative movement with respect to the fixed point marked on the lower limb. The results prove that the knee joint established in the sagittal plane does not show the behavior of a complete joint (a joint with one degree of freedom) as it has been described in other studies.

El propósito de este trabajo de investigación es simular el proceso de osteogénesis y la curación secundaria de fractura, de forma que el modelo desarrollado permita conocer y predecir la evolución del crecimiento óseo y los aspectos de la reparación tales como la geometría externa, la arquitectura interna y el tiempo de curación en respuesta al estímulo mecánico aplicado. De acuerdo a estudios del tejido óseo, la reparación de fractura tiene alta dependencia de factores locales mecánicos y fisiológicos manifestados a nivel celular, lo que hace complejo predecir cuál es el camino que va a seguir la fractura en su proceso de curación. Sin embargo, para cada tipo específico de fractura y la región anatómica afectada se determina un procedimiento específico de atención que permite conocer y controlar su proceso de sanación. Las predicciones de esta investigación están basadas precisamente sobre estos parámetros. El modelo presentado simula el comportamiento de la reparación a nivel celular gracias a la implementación de los Autómatas Celulares, pequeñas maquinas matemáticamente configuradas para tomar decisiones de evolución en el tiempo de acuerdo a los estados propios y de sus inmediatos vecinos. La simulación termina presentando una propuesta de geometría y arquitectura final de la unión ósea entre los segmentos, además de estimar el tiempo requerido en dicha reparación. / Abstract. The aim of this research work is to simulate osteogenesis process and secondary bone healing, in this way developed model allow knows and predicts bone growth evolution and reparation aspects like outer geometry, internal architecture and bone healing time in response to applied mechanical stimulus. According to bone tissue studies, bone healing has a high dependence from mechanical and physiological factors evident at cellular level, becoming complex to predict which one way fracture follows in healing process. However, for each specific kind of fracture and affected anatomical part is determined a specific assistance procedure to make enable knows and take control over healing process. Predictions of this research are based right that in those parameters. Presented model simulates healing behavior at cellular level thanks to use of Cellular Automaton, small machines configured by mathematical statements for take decisions of time{evolution according to own states and states of its neighborhood. Simulation finish showing a geometry and final architecture proposals of bony join between segments in addition to estimate request repair time. Maestría

For the believer, we were expelled from Paradise and hence our suffering began. In one way or another, here and now, we are still vulnerable. Regardless of gender, color, race, belief or condition, we are human beings. "If you prick us, do we not bleed?" said Shylock. We are humans wandering about the Earth and through time, in vain seeking the lost invulnerability we shall never regain. If we venture through the past of the different cultures to the present day, invulnerability's is a story of man's overcoming of adversity, a question of good physical, psychological and social health. It may seem an illusion to some, a mirage or unattainable dream for others, but we refuse to give up on it since we first treaded on this planet. What can we learn from history? Basically: to resist adversity and keep on going convinced that in spite of our traumatic experiences, life is worth living.

This paper investigates a new way for modelling the nonlinear behavior present in athological voice signals. The main idea is modelling the timedelay reconstructed attractors, taking into account the spatial and temporal information of the trajectories by means of a discrete Hidden Markov model (HMM). When the attractors are modeled with HMM it is possible to compute a probabilistic kernel-based distance among models to construct a dissimilarity space. This approach enables the possibility of comparing attractor families by their profiles, rather than evaluating individual nonlinear features of each subject. Classification of dissimilarity space is carried out by using a naive 1-nearest neighbors rule and it is compared with another classification scheme that employs two conventional nonlinear statistics: largest Lyapunov exponent and correlation dimension. Results show that the maximum accuracy with the proposed scheme is a 18.71% greater than the maximum accuracy obtained from the classification based on the conventional nonlinear statistics. En este trabajo se investiga una forma alternativa de modelar el comportamiento no lineal presente en las señales de voz patológicas. El método consiste en modelar atractores reconstruidos mediante la técnica de retardo de tiempo, teniendo en cuenta la información espacial y temporal de las trayectorias en el atractor a partir de modelos ocultos de Markov (HMM) discretos. A partir de modelos HMM entrenados para los espacios embebidos es posible calcular una medida de distancia basada en un kernel probabilístico, que posibilita la construcción de un espacio de disimilitud. Esta aproximación permite la comparación de familias de atractores a partir de la comparación de prototipos en lugar de evaluar características no lineales individuales de cada sujeto. La clasificación del espacio de disimilitud se lleva a cabo usando un clasificador por vecino más cercano y se compara con otro esquema de clasificación que emplea dos características convencionalmente empleadas en análisis no lineal: máximo exponente de Lyapunov y dimensión de correlación. Los resultados muestran que la máxima eficiencia alcanzada con el esquema propuesto es un 18,71% más alta que la máxima exactitud obtenida a partir de clasificación basada en estadísticas no lineales convencionales.

El manejo del choque septico necesita de un tratamiento temprano y apropiado para mejorar su pronostico. Con una administracion temprana de los antibioticos apropiados, el drenaje de las fuentes de infeccion, un manejo hemodinamico optimizado, el uso de ventilacion de proteccion pulmonar y el uso juicioso de los esteroides y la insulinoterapia, la meta en la reduccion de la mortalidad puede ser alcanzada.

There is a cause of death in the Anglo-Saxon paleoanthropology known as "left behind". Injured, handicapped, sick, elders, defenseless children, immigrants, homeless, war victim are "left behind" by our civilization, suffering from that we could denominate the left-behind syndrome. The compassion that moves us to pay attention to people who are left behind is what makes us more humans. To treat and diminish the effects of this social and sanitary syndrome, some laws have been promulgated, quality studies and social policies have been implemented and non-governmental organizations (NGOs) and outpatient associations have been constituted. Medicine has to make an effort to find solutions to discharged patients from hospitals, specially from critical care units, so they could recover and get back to society. In conclusion, there is still a lot to do in society and medicine for the treatment of this syndrome or what is the same, much compassion to exert.