Control y medida de nivel de líquido por medio de un sensor de presión diferencial

En la industria se observa la necesidad de automatizar y controlar el nivel de gases, vapores y líquidos los cuales pueden ser agresivos, no agresivos y peligrosos, así también cada uno de estos con sus respectivos niveles de viscosidad y densidad. En los sistemas de control automático, es de vital importancia que los dispositivos que actúan como elementos integradores del mismo, ofrezcan un nivel de seguridad que permita garantizar el desarrollo completo del proceso en ejecución en industrias tales como las alimenticias, refresqueras, manufactureras, comerciales, entre otras. Esta es la razón por la cual se debe utilizar un sensor de presión diferencial en la medida de nivel de líquidos en los sistemas hidráulicos

Phylogenetic reconstruction using secondary structures of Internal Transcribed Spacer 2 (ITS2, rDNA): finding the molecular and morphological gap in Caribbean gorgonian corals

<p>Abstract</p> <p>Background</p> <p>Most phylogenetic studies using current methods have focused on primary DNA sequence information. However, RNA secondary structures are particularly useful in systematics because they include characteristics, not found in the primary sequence, that give "morphological" information. Despite the number of recent molecular studies on octocorals, there is no consensus opinion about a region that carries enough phylogenetic resolution to solve intrageneric or close species relationships. Moreover, intrageneric morphological information by itself does not always produce accurate phylogenies; intra-species comparisons can reveal greater differences than intra-generic ones. The search for new phylogenetic approaches, such as by RNA secondary structure analysis, is therefore a priority in octocoral research.</p> <p>Results</p> <p>Initially, twelve predicted RNA secondary structures were reconstructed to provide the basic information for phylogenetic analyses; they accorded with the 6 helicoidal ring model, also present in other groups of corals and eukaryotes. We obtained three similar topologies for nine species of the Caribbean gorgonian genus <it>Eunicea </it>(candelabrum corals) with two sister taxa as outgroups (genera <it>Plexaura </it>and <it>Pseudoplexaura</it>) on the basis of molecular morphometrics of ITS2 RNA secondary structures only, traditional primary sequence analyses and maximum likelihood, and a Bayesian analysis of the combined data. The latter approach allowed us to include both primary sequence and RNA molecular morphometrics; each data partition was allowed to have a different evolution rate. In addition, each helix was partitioned as if it had evolved at a distinct rate. <it>Plexaura flexuosa </it>was found to group within <it>Eunicea</it>; this was best supported by both the molecular morphometrics and combined analyses. We suggest <it>Eunicea flexuosa </it>(Lamouroux, 1821) comb. nov., and we present a new species description including Scanning Electron Microscopy (SEM) images of morphological characteristics (sclerites). <it>Eunicea flexuosa</it>, <it>E. pallida</it>, <it>E. laxispica </it>and <it>E. mammosa </it>formed a separate clade in the molecular phylogenies, and were reciprocally monophyletic with respect to other <it>Eunicea </it>(<it>Euniceopsis </it>subgenus, e.g. <it>E. tourneforti </it>and <it>E. laciniata</it>) in the molecular morphometrics tree, with the exception of <it>E. fusca</it>. Moreover, we suggest a new diagnostic character for <it>Eunicea</it>, also present in <it>E. flexuosa</it>: middle layer sclerites > 1 mm in length.</p> <p>Conclusion</p> <p>ITS2 was a reliable sequence for intrageneric studies in gorgonian octocorals because of the amount of phylogenetic signal, and was corroborated against morphological characters separating <it>Eunicea </it>from <it>Plexaura</it>. The ITS2 RNA secondary structure approach to phylogeny presented here did not rely on alignment methods such as INDELS, but provided clearly homologous characters for partition analysis and RNA molecular morphometrics. These approaches support the divergence of <it>Eunicea flexuosa </it>comb. nov. from the outgroup <it>Plexaura</it>, although it has been considered part of this outgroup for nearly two centuries because of morphological resemblance.</p

Desarrollo de las competencias básicas en la práctica pedagógica : formar y evaluar

El presente trabajo que lleva por título "Desarrollo de las Competencias Básicas en la Práctica Pedagógica: Formar y Evaluar”, se definen y reflexionan las categorías “Formar y Evaluar” y las subcategorías “Práctica pedagógica”, “Virtualidad” y “Pedagogía ignaciana”, a través de un proceso colaborativo, valioso, que involucra a los investigadores, en cuanto les permite profundizar teóricamente en las anteriores categorías y subcategorías, también, narrar y analizar sus propias experiencias de “Práctica pedagógica”, a través de la técnica “Historias de vida”, lo cual ofrece un aporte que enriquece al “Programa de la Licenciatura en Ciencias Religiosas de la Pontificia Universidad Javeriana”, ya que es reflexivo, crítico y profundamente vivencial. La Ignacianidad como manera concreta de “ser” y “hacer” en el horizonte formativo y evaluativo de la Pontificia Universidad Javeriana, se encuentra implícita y explícita en el desarrollo del presente escrito, marcando así un sello original que da sentido y perspectiva a nuestra “Práctica pedagógica” como javerianos, a la manera concreta de “ser” y “hacer” en nuestro ejercicio de la docencia. Desde este horizonte somos, en el aula y en la pastoral formadores, formados desde la perspectiva ignaciana, que evaluamos desde un horizonte humano, integral y justo, buscando transformar al ser humano y comprometerlo con su historia, con la vida y con la comunidad.In the present paper which title is ’’Development of the Basic Competences in Pedagogical Practices: Training and Evaluation, the categories “Training and Evaluation” and the subcategones ‘ Pedagogical practice”, “Virtuality” and “Ignatian Pedagogy” are defined and reflected on, by a collaborative and valuable process which involves the investigators and allows them to think deeply theoretically about these categories and subcategories, also, to narrate and analyse their own experiences of “Pedagogical practice” through the tecnique “life history” so adding an element which enriches the programme of Religious studies in the Javeriana Pontifical University program, as it is reflective, critical and profoundly experiential. The Ignacian experience as a concrete way of “being” and “doing” from the training and evaluating perspectives of the Pontifical Javeriana University is encountered implicitly and explicitly in the development of the present paper, thus setting on it an original stamp which gives sense and perspective to our Pedagogical practices as graduates of the Javieriana University and to the concrete manner of “being” and “doing” in exercising our teaching. From this perspective we are, in the classroom as well as in pastoral care shapers, shaped ourselves by the Ignacian view which we evaluate from a human horizon, just and’integral thus looking to transform the human being and committing it to its history, with life and with the community.Licenciado (a) en Ciencias ReligiosasPregrad

Limitaciones a los principios de igualdad y libre concurrencia en la licitación pública

El presente artículo analiza los principios de igualdad y libre concurrencia asociados a ésta modalidad contractual, teniendo como referente el artículo 25 de la Ley 100 de 1993. Lo analizado propone que en la medida que estos principios se limiten, mayor será el riesgo de corrupción y detrimento de lo público

Juicio y Enfermedad: aproximación a las dinámicas de las enfermedades en la Real Audiencia de Santa Fé. 1571

The objective of this dissertation is to demonstrate and analyze by means of a documentary transcription, the process of an apparent poisoning by herbs, which lies in the background caciques and Indians in the general archive of the nation. The writing is divided into two parts: the first is a brief analysis of the importance, difference and some historiographic considerations around the diseases, social relations and stereotypes in the colonial culture shock present in the document; The second part consists of the documentary transcription of the judicial process against Isabel and Catalina, Ladino Indians, for the alleged poisoning of two girls and a Panche Indian with herbs. It is hoped that this contribution can serve as input and incentive for the development and understanding of some of the colonial themes and dynamics in what is currently Colombia.El objetivo de esta disertación es evidenciar y analizar, por medio de una transcripción documental, el proceso sobre un aparente envenenamiento por yerbas, que reposa en el fondo Caciques e Indios en el Archivo General de la Nación (Bogotá). El escrito está dividido en dos partes: la primera es un breve análisis sobre la importancia, diferencia y algunas consideraciones historiográficas en torno a las enfermedades, las relaciones sociales y estereotipos en el choque cultural colonial presentes en el documento; la segunda parte consta de la trascripción documental sobre el proceso judicial a Isabel y Catalina, indígenas ladinas, por el supuesto envenenamiento con yerbas a dos niñas y un indio panche. Se espera que este aporte pueda servir de insumo e incentivo para el desarrollo y entendimiento de algunas de las temáticas y dinámicas coloniales en lo que actualmente es Colombia

Analysis of solid blends milling using population balances

Particle size distribution (PSD) is a key factor in size reduction processes. These processes are widely used worldwide and in the Colombian industry. However, they represent a high energy consumption process, which requires a careful assessment of the desired particle size and the energy required to obtain it. In order to reduce the capital costs, it is common for some companies to operate grinding stages with blends, reducing the capital costs and time required for the process. However, the blend composition can affect the operating conditions or require a higher energy consumption than grinding the individual components. Population balance modeling (PBM) can be used to describe the rate at which a material is being ground, and therefore, predict the time and energy required to obtain a desired PSD. In this work, the grinding behavior of two different materials and their blend in a batch size reduction process using a laboratory-scale steel ball mill was studied. The operating conditions were kept constant in order to study the evolution of PSD with time. The results obtained showed a good correlation between PSD and time using PBM for the pure materials. The blend could not be explained by a linear combination of the parameters. Further work is necessary to study blends in milling processes. It was also possible to determine the effect of grinding media size and mill filling in the rate of breakage of solids. However, the applicability of the model was only adequate for the coarser sizes of the samples, as shown by validation experiments

Assessment of needle tip geometry during infusions into a brain phantom gel: Evaluación de la geometría de la punta de la aguja durante infusiones en gel de agarosa

Convection-enhanced delivery (CED) is a promising method to deliver therapeutic drugs directly into the brain that has shown limited efficacy, mainly attributed to backflow, in which the infused drug flows back along the needle track rather than forward into tissue. This study evaluates the effect of sharp and blunt needle tips on backflow length under different flow rates via CED. Infusions were performed in a transparent 0.6% (w/v) brain phantom agarose hydrogel. Backflow length was significantly higher using sharp-tip needles for higher flow rates. No significant differences were observed between tip shapes for lower flow rates. In conclusion, sharp-tip needles present limitations for higher flow rates, which are needed to deliver more drug during shortest times.Convection-enhanced delivery es una técnica para suministrar drogas directamente en el cerebro para el tratamiento de enfermedades del sistema nervioso central. Este método ha mostrado una limitada eficacia atribuida principalmente al fenómeno de backflow, en el cual, la sustancia fluye hacia atrás por fuera de la aguja en vez de alcanzar la región del tejido delante de la punta. Este estudio evalúa el efecto de los tipos de punta plana y biselada sobre el fenómeno de backflow bajo diferentes caudales. Las infusiones experimentales se realizaron en gel de agarosa transparente al 0.6% (w/v). La longitud de backflow fue significativamente mayor para infusiones con aguja biselada a caudales mayores. No se observaron diferencias significativas entre ambos tipos de aguja para caudales menores. En conclusión, agujas con punta biselada presentan limitaciones a mayores caudales, las cuales son requeridas para suministrar mayor cantidad de fármaco durante los procedimientos clínicos