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Objetivo: durante los últimos años, las actividades de ciencia ciudadana han cobrado mayor interés, debido a que contribuyen a la recopilación de nueva información y a generar nuevas preguntas de investigación. El propósito de este trabajo es presentar un ejercicio de ciencia ciudadana enfocado en la evaluación de la calidad del aire y la caracterización de microfauna acuática del humedal Juan Amarillo de la ciudad de Bogotá. Métodos: se diseñó un estudio longitudinal desde la perspectiva de la ciencia ciudadana que involucró mediciones de material particulado 2,5 (PM2,5) en la ciclorruta del humedal Juan Amarillo. El recorrido fue dividido en dos zonas. Se realizó una caracterización de la microfauna acuática residente en el humedal mediante observación con microscopio óptico y estereoscopio. Resultados: las concentraciones de PM2,5 fueron significativamente mayores en la zona 1 comparadas con las de la zona 2 (p < 0,001). Se identificaron diferentes especies de macroinvertebrados pertenecientes a los grupos Gastropoda, Oligochaeta, Hirudínea. Conclusiones: se estableció una relación entre la concentración de PM2,5 y las condiciones ambientales de la ruta. Se identificaron algunos microorganismos que podrían ser usados como bioindicadores de la calidad del agua. Las actividades de ciencia ciudadana pueden ser útiles para acercar a niños(as) a la ciencia.

AimWhile species’ niches are understood to diverge through time, the mode of these divergences is not fully understood. The null hypothesis of niche divergence in the present is that of conservatism; that species are likely to occur in the same environment as their ancestors and, therefore, as allopatric sister species. Alternatively, species are expected to diverge when selective pressure, such as parapatry with a congener, occurs. Here, we analyse niche divergence in a mosaic of allo- and parapatricSclerurus mexicanussensu lato populations to determine if niche divergence is more likely in parapatry.LocationNeotropics.MethodsWe created a dataset of 1,100 vetted localities forS. mexicanussensu lato, and assigned each point to each of the seven described populations. We created individual dispersal areas for each species in Maxent following: 1) a broad approach in which training areas where allowed to overlap with parapatric congeners; and 2) a narrow approach in which species dispersal areas adhered to strict parapatry and there was no overlap in training areas. We complemented these ENMs with ‘random’ models drawn from points within each training area, thus creating ‘null’ ENMs against which we could test niche divergence using the metric Schoener’s D.ResultsThere was no significant difference in the performance of broad and narrow training areas. Few significant divergences were found, and all of those that were found consisted of allopatric populations. Partial divergences were frequently recovered when comparing parapatric taxa.Main conclusionsIn contrast to our expectation, we found no significant evidence for increased niche divergence in parapatric versus allopatric species. Possible explanations for these findings include true conservatism even among parapatric lineages (e.g., additional environmental or biological factors may delimit distributions) or artefactual errors inherent to model creation. We discuss the implications of these findings, and discuss ways to improve upon tests of niche divergence in the future, especially when dealing with cases of parapatry.

This study generalizes the notion of distance via defining an axiomatic collective distance, between arbitrary vector sets. A first part discusses conceptual tools, which can be later useful for general mathematical practice or as computational quantum similarity indices. After preliminary definitions, two elements, which can be associated with arbitrary sets of a vector space, are described: the centroid and the variance vectors. The Minkowski norm of the variance vector is shown to comply with the axioms of a collective distance. The role of the Gram matrix, associated with a vector set, is linked to the definition of numerical variance. Several simple application examples involving linear algebra and N-dimensional geometry are given. In a second part, all previous definitions are applied to quantum multimolecular polyhedra (QMP), where a set of molecular quantum mechanical density functions act as vertices. The numerical Minkowski norm of the variance vector in any QMP could be considered as a superposition of molecular contributions, corresponding to a new set of quantum similarity indices, which can generate intrinsic ordering among QMP vertices. In this way, the role of quantum similarity matrix elements is evidenced. Application to collections of molecular structures is analyzed as an illustrative practical exercise. The connection of the QMP framework with classical and quantum quantitative structure–properties relation (QSPR) becomes evident with the aid of numerical examples computed over several molecular sets acting as QMP. WIREs Comput Mol Sci 2015, 5:380–404. doi: 10.1002/wcms.1223 For further resources related to this article, please visit the WIREs website.

resultado del proyectoEl artículo analiza las interpretaciones sobre la deserción en la universidad Colombiana. Las miradas usuales sobre deserción se orientan a reflexionar y ofrecer mecanismos de intervención en las universidades, sin relacionarlo con la disminución del valor social de la educación superior. Para comprender la deserción, es necesario acercase a los roles y los lazos que en campo educativo desarrollan: estudiantes, universidades y gobierno. Las fuentes utilizadas son investigaciones, reflexiones e informes de instituciones públicas sobre deserción. Las preocupaciones actuales se orientan a retener a los potenciales desertores, no a entender cómo universidad, sociedad y Estado, no ofrecen las condiciones para que los jóvenes proyecten su futuro, que materialicen sus sueños y anhelos, en un contexto con pocas opciones laborales y constantes crisis económicas y sociales.

La alta morbimortalidad en aneurismas intracraneales exige la identificación rápida de los síntomas de alarma y el tratamiento oportuno en caso de ruptura. De ahí la importancia de las imágenes diagnósticas para identificar a los pacientes en riesgo y definir el manejo endovascular o quirúrgico. Revisamos los criterios para el uso del stent redireccionador de flujo en aneurismas intracraneales, método endovascular que reduce las comorbilidades, el tiempo quirúrgico y la estancia hospitalaria. Estudio descriptivo retrospectivo de 2010 a 2012 de siete casos. Se presentan las complicaciones siendo la cefalea y la trombosis posterior al procedimiento las más frecuentes. El tratamiento endovascular es seguro, eficaz e innovador y por tanto puede implementarse y difundirse. Abreviaturas: AI, aneurisma (s) intracraneal (es).

Neste trabalho, apresenta-se o estudo comparativo entre a produção de energia real do parque eólico Villonaco e a produção de energia calculada por Meteodyn WT, que é uma ferramenta CFD (Computational Fluid Dynamics) baseada num modelo de fluxo não lineal e nas equações tridimensionais de Reynolds, Averaged Navier-Stokes. O parque eólico em análise, com uma potência instalada de 16.5 MW, está localizado na província de Loja no sul do Equador, instalado em terreno montanhoso em uma altitude aproximada de 2720 metros sobre o nível do mar, em um setor que opera em condições extremas com velocidade média anual do vento acima de 10.5 m/s e alta complexidade orográfica. Os resultados do modelamento mostram uma produção anual de energia (AEP) do parque eólico Villonaco de 74.8 GWh por ano, um fator de capacidade (CF) de 51% e um total de 4496.2 horas de operação por ano (horas em plena carga), dados que se aproximam da produção real dos registros existentes no parque.