Protocolo experimental para la evaluación de microemulsiones que modifican la mojabilidad en el medio poroso. Aplicación a campos colombianos

Las reservas de crudo liviano son cada vez más escasas, a diferencia de los descubrimientos de crudo pesado, razón por lo cual se ha enfocado la atención en este tipo de hidrocarburos. Colombia tiene un gran potencial de crudo pesado, sobre todo en las zonas de la Cuenca de los Llanos Orientales (Campos: Rubiales, Castilla, Chichimene, Apiay, Suria), cuyo desarrollo en los últimos años, ha logrado que el 60% de la producción nacional este asociada a este tipo de recurso. La producción de crudo pesado no es fácil, una de las principales dificultades es la alta viscosidad del hidrocarburo, lo cual origina una baja movilidad del mismo y una temprana producción de agua en yacimientos con acuíferos activos. Una de las técnicas más utilizadas para incrementar la productividad en los yacimientos de crudos pesados es la estimulación matricial de pozos, a partir de la cual se pueden modificar las curvas de permeabilidad relativa (alteración de la humectabilidad) y así mejorar la movilidad de estos crudos. Sin embargo es crucial la comprensión de la mojabilidad de la formación para optimizar la recuperación de petróleo. Suponer que una formación es mojable por agua, cuando en realidad no lo es, puede ocasionar daños irreversibles en el yacimiento. Por lo anterior, el presente estudio se centró en desarrollar e implementar un protocolo a nivel de laboratorio, para evaluar tratamientos de estimulación matricial base agua, que tuvieran la capacidad de invertir la mojabilidad natural (generalmente al crudo, debido a la alta afinidad entre el crudo y minerales de roca del yacimiento), hacia una mojabilidad al agua, que conduce a un mejoramiento de la permeabilidad relativa al crudo. El protocolo experimental fue implementado a nivel de laboratorio en el campo Castilla (cuenca de los llanos orientales en Colombia) y se enfocó en tres grandes etapas. 1. Etapa 1: Caracterización básica de fluidos de formación 2. Etapa 2: Evaluación fluido-fluido y comportamiento reológico de fluidos de formación Vs Tratamientos químicos. 3. Etapa 3: Evaluación del efecto sobre la humectabilidad (modificación de ángulos de contacto y permeabilidad relativa). Las principales conclusiones y recomendaciones obtenidas en este estudio son las siguientes: 1. Se desarrolló un protocolo experimental adecuado para la evaluación de microemulsiones y/o aditivos mejoradores de movilidad. 2. La implementación del protocolo permitió seleccionar el mejor tratamiento de alteración de la humectabilidad para el campo Castilla. 3. En la preferencia de la mojabilidad del yacimiento, tienen incidencia: los componentes del petróleo, la química de la salmuera, la superficie mineral, la temperatura, la presión, la tensión interfacial de los fluidos, la presión capilar y la historia de saturación del yacimiento.Reserves of light crude oil are decreasing in contrast to the discoveries of heavy crude which is why attention has been focused on this type of hydrocarbons. Colombia has a high potential in the heavy-crude development especially in the areas of the Llanos Orientales Basin (Campos: Rubiales, Castilla, Chichimene, Apiay, Suria) which have been produced in recent years to achieve that the 60% of the national production is associated with this type of resource. Heavy-oil production is not easy due to its high viscosity which causes low oil mobility and early water production in reservoirs with active aquifers. One of the main techniques used to increase productivity in heavy crude oil fields is the matrix stimulation of wells through the injection of treatments that positively alter the relative permeability curves (alteration of wettability) and thus improve the mobility of these crude oils. However, understanding the formation wettability is essential to optimize oil recovery. To assume that a formation is wettable by water, when in reality it is not, can cause irreversible damage to the reservoir. Therefore, the current study focused on developing and implementing a protocol at the laboratory level, to evaluate water-based matrix stimulation treatments that have ability to reverse natural oil wettability (generally to the oil, due to high affinity between oil and rock minerals of reservoir) towards water wettability, which leads to an improvement of relative permeability to crude oil. The experimental protocol was implemented at laboratory level for the Castilla Oilfield (Llanos Orientales basin in Colombia) and focused on three major stages. 1. Stage 1: Basic characterization of treatment fluids. 2. Stage 2: Fluid-fluid evaluation and rheological behavior of formation fluids Vs. Chemical treatments. 3. Stage 3: Evaluation of effect on wettability (modification of contact angles and relative permeability). The main conclusions and recommendations obtained in this study are the following: 1. A suitable experimental protocol was developed for evaluation of microemulsions and / or mobility enhancing additives. 2. Implementation of protocol allowed selecting the best treatment of alteration of wettability for the Castilla oilfield. 3. The components of the oil, the brine chemistry, the mineral surface, the temperature, the pressure, the interfacial tension, the capillary pressure, the saturation history of reservoir, among other properties have an impact on the reservoir’s wettability

El reducido nivel de participaci?n de las medianas empresas en el mercado alternativo de valores como fuente de financiamiento para satisfacer sus necesidades de liquidez en el corto plazo

El ?xito del sector empresarial en el Per? depende en gran medida de las diversas fuentes de financiamiento que sus participantes pueden encontrar en el mercado. En este sentido, el brindarles conocimiento de todas las fuentes posibles y educarlos de tal forma que puedan aprovecharlas en alto nivel, es tambi?n labor de los entes reguladores y por ende del Estado. El presente trabajo de investigaci?n expone al MAV (?Mercado Alternativo de Valores?) como una variante del Mercado de Valores, el cual ha sido dise?ado para que las Medianas Empresas exploren una alternativa que antes, por sus condiciones anteriores, le era pr?cticamente inalcanzable. Asimismo, desde las perspectivas de las Medianas Empresas, se busca descubrir el por qu?, desde su creaci?n (2012), el MAV ha tenido tan poca participaci?n a pesar de lo exitoso que han sido los casos registrados. Esta cuesti?n ha sido desarrollada durante el presente documento mediante una investigaci?n exploratoria de tipo cualitativa, con la finalidad de poder realizar recomendaciones en b?squeda de su mayor concurrencia

El impacto de la pandemia del COVID-19 en la educación médica: adaptabilidad y experiencia con enseñanza a distancia de la Sociedad Médica Peruano Americana

The COVID-19 pandemic had a significant impact on medical care and medical education in Peru.  In response, the Peruvian American Medical Society (PAMS), a charitable medical organization based in the USA, pursued its medical and educational missions in Peru by adopting virtual learning technology. We developed closer collaborative relationships with several medical schools and the Peruvian Association of Medical Schools (ASPEFAM) while offering a faculty panel of twenty-four members to provide lectures and multidisciplinary webinars in Spanish. We conducted 19 webinars including COVID -19 and non-COVID-19 related topics that over the last two years attracted 14,489 participants from 23 countries. They were the foundation for twenty publications in Peruvian medical journals. Our clinical investigations competition was positively received as was our pilot project on research mentorship. The COVID -19 pandemic had a positive effect on the educational mission of PAMS in Peru.La pandemia del COVID-19 tuvo un impacto significativo en el cuidado y la educación médicos en el Perú. En respuesta, la Sociedad Médica Peruano Americana (PAMS), una organización médica benéfica con sede en los EE. UU., adoptó sus misiones médicas y educativas en Perú usando estrategias virtuales. Desarrollamos colaboración con varias facultades de medicina y la Asociación Peruana de Facultades de Medicina (ASPEFAM) y ofrecimos un panel de veinte y cuatro miembros para brindar conferencias y seminarios multidisciplinarios en español. Hicimos 19 seminarios, incluyendo temas relacionados y no relacionados al COVID-19, que en los últimos dos años atrajo a 14 489 participantes de 23 países. Ellas fueron la base de 20 publicaciones en revistas médicas peruanas. Nuestro concurso de investigaciones clínicas y nuestro proyecto piloto de mentoría de investigación fueron recibidos positivamente. La pandemia del COVID-19 tuvo un efecto positivo en la misión educativa de PAMS en Perú

DeadEasy Mito-Glia: Automatic Counting of Mitotic Cells and Glial Cells in Drosophila

Cell number changes during normal development, and in disease (e.g., neurodegeneration, cancer). Many genes affect cell number, thus functional genetic analysis frequently requires analysis of cell number alterations upon loss of function mutations or in gain of function experiments. Drosophila is a most powerful model organism to investigate the function of genes involved in development or disease in vivo. Image processing and pattern recognition techniques can be used to extract information from microscopy images to quantify automatically distinct cellular features, but these methods are still not very extended in this model organism. Thus cellular quantification is often carried out manually, which is laborious, tedious, error prone or humanly unfeasible. Here, we present DeadEasy Mito-Glia, an image processing method to count automatically the number of mitotic cells labelled with anti-phospho-histone H3 and of glial cells labelled with anti-Repo in Drosophila embryos. This programme belongs to the DeadEasy suite of which we have previously developed versions to count apoptotic cells and neuronal nuclei. Having separate programmes is paramount for accuracy. DeadEasy Mito-Glia is very easy to use, fast, objective and very accurate when counting dividing cells and glial cells labelled with a nuclear marker. Although this method has been validated for Drosophila embryos, we provide an interactive window for biologists to easily extend its application to other nuclear markers and other sample types. DeadEasy MitoGlia is freely available as an ImageJ plug-in, it increases the repertoire of tools for in vivo genetic analysis, and it will be of interest to a broad community of developmental, cancer and neuro-biologists

Stratification of hospitalized COVID-19 patients into clinical severity progression groups by immuno-phenotyping and machine learning

Quantitative or qualitative differences in immunity may drive clinical severity in COVID-19. Although longitudinal studies to record the course of immunological changes are ample, they do not necessarily predict clinical progression at the time of hospital admission. Here we show, by a machine learning approach using serum pro-inflammatory, anti-inflammatory and anti-viral cytokine and anti-SARS-CoV-2 antibody measurements as input data, that COVID-19 patients cluster into three distinct immune phenotype groups. These immune-types, determined by unsupervised hierarchical clustering that is agnostic to severity, predict clinical course. The identified immune-types do not associate with disease duration at hospital admittance, but rather reflect variations in the nature and kinetics of individual patient's immune response. Thus, our work provides an immune-type based scheme to stratify COVID-19 patients at hospital admittance into high and low risk clinical categories with distinct cytokine and antibody profiles that may guide personalized therapy. Developing predictive methods to identify patients with high risk of severe COVID-19 disease is of crucial importance. Authors show here that by measuring anti-SARS-CoV-2 antibody and cytokine levels at the time of hospital admission and integrating the data by unsupervised hierarchical clustering/machine learning, it is possible to predict unfavourable outcome

Imprisoned Indigenous women and the shadow of colonial patriarchy

Imprisonment in Australia has been a growing industry and large numbers of vulnerable people find themselves in a state of serial incarceration. Women and Indigenous peoples in particular have experienced rapidly expanding imprisonment rates over recent decades. Our argument in this article is relatively straightforward: to understand contemporary penal culture and in particular its severity and excess in relation to Indigenous people and women, we need to draw upon an understanding of the dynamics of colonial patriarchy. We develop this understanding through a specific focus on Indigenous women. Although at a micro level, specific legislation and policy changes have had a negative impact on the imprisonment of vulnerable groups, it is within a broader context of the strategies and techniques of colonial patriarchy that we can understand why it is that particular social groups appear to become the targets of penal excess