Topography, extracellular matrix proteins, secreted molecules and endogenous electric fields: cues that influence the differentiation of neural progenitor cells

Neural progenitor cells (NPCs) have the potential to be used as a cell based therapy to treat Alzheimer disease, spinal cord injury and other significant damage to the central nervous system. In order to utilize the therapeutic potential of NPCs, we must first learn to control their migration, proliferation, differentiation and growth. An ideal methodology would entail directed stem cell migration to damaged tissue; proliferation until the target is reached; differentiation into the most beneficial phenotype; and integration of cells into the existing tissue. A myriad of stimulants that alter NPC behavior, exist in vivo. Characterizing the individual contributions of each stimulant or cue in vivo can be difficult to deconvolute, unless discerned in vitro. We investigate several of these cues individually and synergistically. We focus on the influence of extracellular matrix proteins, components secreted from surrounding cells in the central nervous system (i.e. - astrocytes, microglia) and the physical micro- and nano-architecture surrounding NPCs. One other stimulus that has not been explored much, but is investigated here extensively, is the influence of electric fields that mimic the electric gradient existent in the developing and adult nervous system. We investigate the contribution of electric fields as stimuli to NPCs and the possible use of electric fields to reap the therapeutic potential of NPCs. In summary, investigation of the influence of a synergistic combination of external cues on the behavior of neural progenitor cells provides insights into their behavior and enables potential control of stem cell differentiation

Solución de Dos Estudios de Caso Bajo el Uso de Tecnología CISCO

La evaluación denominada “Prueba de habilidades prácticas”, forma parte de las actividades evaluativas del Diplomado de Profundización CCNA, y busca identificar el grado de desarrollo de competencias y habilidades que fueron adquiridas a lo largo del diplomado. Lo esencial es poner a prueba los niveles de comprensión y solución de problemas relacionados con diversos aspectos de Networking.The evaluation called "Test of practical skills", is part of the evaluation activities of the CCNA Deepening Diploma, and seeks to identify the degree of development of skills and abilities that were acquired throughout the course. The essential thing is to test the levels of understanding and solving problems related to various aspects of Networking

War, the United Nations, and Peacekeeping

While the amount of interstate war in the international system had declined by 2013, since then both intrastate and internationalized intrastate war has increased. In 2015 there are sixteen UN peacekeeping operations around the globe, involving about 130,000 military, police, and civilian personnel. Over the past seventy years, UN peacekeeping operations have evolved from simple buffer forces tasked with observing cease-fires and armistices to complex multidimensional operations in intrastate conflicts, involving peacebuilding in an increasingly dangerous environment

Valores, actitudes y motivaciones en la juventud ante el emprendimiento individual y colectivo

En el presente trabajo se recopilan una serie de datos recientes –extraídos de diversas fuentes estadísticas acerca de la situación de la juventud y sus expectativas laborales en España y en Andalucía– para contrastar en qué medida las formas de emprendimiento individual y colectivo se presentan como una alternativa cada vez más asequible para este colectivo. En primer lugar se contextualiza hasta qué punto crear una empresa es una opción de inserción laboral en la juventud española. Seguidamente se profundiza en la vocación emprendedora, el asociacionismo y en el conocimiento de la economía social –en este caso de la juventud andaluza–. Por último se proponen algunas ideas conclusivas, a raíz de los datos expuestos, ya que las actitudes manifestadas pueden ser un indicador de las oportunidades u obstáculos que existen para el desarrollo de este tipo de fórmulas empresariales para el futuro

The Philosophy of Chemistry as an Epistemological Reference in the Construction of a ‘Nature of Science’ for Chemistry Teacher Education

En este trabajo pretendemos abordar la pregunta de qué referencia(s) epistemológica(s) puede(n) constituir la base para construir una imagen de la química y de los químicos que se adecue a los desarrollos actuales de la filosofía de la ciencia y al requerimiento contemporáneo de conseguir una educación científica de calidad para todos. Partiendo de la literatura acerca de la naturaleza de la ciencia, sostenemos la idea de que, si bien se pueden identificar algunos referentes epistemológicos generales, parece emerger la reciente filosofía de la química como un referente epistemológico que puede considerarse fructífero para la actual didáctica de la química. Este referente podría considerarse novedoso y a la vez cercano a la contemporánea “concepción semántica de las teorías científicas”.In this paper we intend to address the question of which epistemological reference(s) can constitute the basis to construct an image of chemistry and chemists that fits current developments in the philosophy of science and the contemporary requirement to achieve a quality science education for all. Based on the literature about the nature of science, we adhere to the idea that, although some general epistemological references can be identified, there also seems to emerge the recent philosophy of chemistry as an epistemological referent that can be considered fruitful for current didactics of chemistry. This reference could be considered new and at the same time close to the contemporary “semantic conception of scientific theories”.peerReviewe

Nuevas tecnologías y aprendizaje matemático en niños con síndrome de down: generalización para la autonomía

El presente trabajo analiza el efecto del uso de materiales multimedia en el aprendizaje de contenidos matemáticos y sus posibilidades de generalización a personas con síndrome de Down. Dos grupos de niños fueron instruidos, con distintas metodologías de enseñanza, en los principios de conteo y cantidad. Mientras un grupo trabajó con material multimedia, el otro lo hizo con una metodología tradicional de lápiz y papel. Tras el proceso de enseñanza, ambos grupos fueron evaluados mediante una tarea que simulaba una situación de compra. Los resultados sugieren un claro efecto facilitador de la metodología multimedia en la generalización de los conceptos y habilidades básicos de conteo en niños con síndrome de Down.The present study aims to explore the effect of using multimedia material on the learning and generalization of mathematical contents in Down syndrome children. Two groups of children were trained in the principles of counting and cardinality. One group learned by means of a computer-assisted teaching and the other did it by using a paperand-pencil-based methodology. After the teaching process, both groups were assessed with a task pretending a shopping setting. The results strongly suggest an effect of multimedia teaching to facilitate the generalization of the concepts and skills learned by Down syndrome children

Construcción de la violencia en el fútbol : la psicologización del hincha

El fenómeno de la violencia asociada al fútbol no está desarticulado de las formas como los grupos sociales elaboran y reproducen significados, lo cual plantea la necesidad de producir comprensiones sobre los procesos discursivos que generan y mantienen la violencia. Abordamos el estudio por medio de la metodología cualitativa en especial a través del Análisis del Discurso. Tomamos como muestra 188 artículos periodísticos del diario El Colombiano en el periodo comprendido entre los años 2010 y 2015. Encontramos que la prensa sitúa al "hincha" como eje central a la hora de referirse al fenómeno de la violencia en el fútbol, apelando a la psicologización y criminalización de este para explicar la violencia en el contexto del fútbol.The phenomenon of violence associated to the football is not disarticulated from the ways social groups produce and reproduce meanings, which raises the need to produce comprehensions about the discursive processes that generate and maintain violence. We Approach to the study using qualitative methodology especially through discourse analysis. The sample was made from 188 news from the newspaper El Colombiano in the period between 2010 and 2015. We found that the press places the "fan" as a central axis when referring to the phenomenon of football violence, appealing to the psychologization and criminalization of this to explain the violence in the context Entertainment soccer

Analysis of the tensile fracture properties of ultra-high-strength fiber-reinforced concrete with different types of steel fibers by X-ray tomography

This study is concerned with the analysis of the tensile properties of an ultra-high-strength fiber-reinforced concrete manufactured with short and long steel fibers. The analysis involve using different techniques - from mechanical tests to X-ray computed tomography - to relate the observed variation of the mechanical properties of the mixes with their porosity. A comprehensive study of the porosity distribution was conducted on the basis of the analysis of X-ray computed tomography images and porosimetry. The study shows the influence of the type of fiber used in the reinforcement on the pore size and distribution of the concrete matrix and consequently on its tensile properties. The tensile properties are obtained with an inverse analysis method available in the literature that yielded the first-cracking tensile strength (f t ) and the ultimate tensile strength (f tu ) and related with the inner structure of the concrete matrix. Our results prove that the tensile properties, especially the first-cracking strength, vary depending on the fibers used. These findings help mix designers make a decision about the type of fibers that should be used when a high first-cracking tensile strength is needed and make it possible to quantify the effect of the fiber.Ministerio de Economía y competitividad BIA2016-75431-RMinisterio de Economía y Competitividad DPI2015-66534-RAcademia de Ciencias de la República Checa 16-18702

A Proposal for a Machine Learning Classifier for Viral Infection in Living Cells Based on Mitochondrial Distribution

The study of viral infections using live cell imaging (LCI) is an important area with multiple opportunities for new developments in computational cell biology. Here, this point is illustrated by the analysis of the sub-cellular distribution of mitochondrium in cell cultures infected by Dengue virus (DENV) and in uninfected cell cultures (Mock-infections). Several videos were recorded from the overnight experiments performed in a confocal microscopy of spinning disk. The density distribution of mitochondrium around the nuclei as a function of time and space ρ(r, θ, t) was numerically modeled as a smooth interpolation function from the image data and used in further analysis. A graphical study shows that the behavior of the mitochondrial density is substantially different when the infection is present. The DENV-infected cells show a more diffuse distribution and a stronger angular variation on it. This behavior can be quantified by using some usual image processing descriptors called entropy and uniformity. Interestingly, the marked difference found in the mitochondria density distribution for mock and for infected cell is present in every frame and not an evidence of time dependence was found, which indicate that from the start of the infections the cells are showing an altered subcellular pattern in mitochondrium distribution. Ulteriorly, it would be important to study by analysis of time series for clearing if there is some tendency or approximate cycles. Those findings are suggesting that using the image descriptors entropy and uniformity it is possible to create a machine learning classifier that could recognize if a single selected cell in a culture has been infected or not

Selective voluntary forgetting in young and older adults

Aging is thought to involve a decline in executive-control capacities, although evidence regarding this claim is not always clear. Thus, although studies exist that suggest impoverished inhibitory memory control in older adults relative to younger adults, experiments with the list-method direct forgetting procedure have mostly failed to show adult-age differences in voluntary forgetting. In the present study we aimed to further study this issue by comparing young-old and young adults’ performance with the selective directed forgetting (SDF) procedure, which we assumed to involve higher demands of executive control than the standard nonselective procedure. Thus, on the basis of previous studies showing that a critical factor in finding adult-age differences in executive-control tasks is the overall challenge posed by the tasks, we predicted less SDF in older adults than in younger adults. Supporting our hypothesis, across three experiments we show evidence of older adults’ impoverished capacity to voluntarily forget episodic memories, although only when the task requires selective forgetting. Ours join other findings to suggest that sensitiveness to detect adult-age differences in cognitive control may strongly depend on the executive-control demands imposed by tasks