Genome Sequences of Actinobacteria from Extreme Environments in Colombia.

We sequenced six actinobacterial genomes isolated from a salt mine and from soil in a high-mountain Páramo ecosystem. The strains belonged to the genera Streptomyces, Nesterenkonia, and Isoptericola and were sequenced due to their antimicrobial and cytotoxic activities

Actividad metacognitiva en estudiantes universitarios

La presente investigación se basa en el modelo de actividad metacognitiva propuesto por Mayor, Suengas y González (1995). Se utilizo el Cuestionario de Autorreporte de Actividad Metacognitiva, que propone la teoría para recolectar la información. Los datos arrojados permiten establecer que en todos los niveles de actividad metacognitiva en la muestra estudiantes I-V-X del programa de psicología, en relación tanto con el semestre como con la edad se ubicaron en un nivel medio bajo, en ningún semestre y en ningún rango de edad se pueden observar niveles altos en los componentes. Por otra parte, no se halló una correlación significativa en la actividad metacognitiva y el semestre académico cursado, tampoco en la edad

Plasmid-encoded toxin of Escherichia coli cleaves complement system proteins and inhibits complement-mediated lysis in vitro

Plasmid-encoded toxin (Pet) is an autotransporter protein of the serine protease autotransporters of Enterobacteriaceae (SPATE) family, important in the pathogenicity of Escherichia coli. The pet gene was initially found in the enteroaggregative E. coli (EAEC) virulence plasmid, pAA2. Although this virulence factor was initially described in EAEC, an intestinal E. coli pathotype, pet may also be present in other pathotypes, including extraintestinal pathogenic strains (ExPEC). The complement system is an important defense mechanism of the immune system that can be activated by invading pathogens. Proteases produced by pathogenic bacteria, such as SPATEs, have proteolytic activity and can cleave components of the complement system, promoting bacterial resistance to human serum. Considering these factors, the proteolytic activity of Pet and its role in evading the complement system were investigated. Proteolytic assays were performed by incubating purified components of the complement system with Pet and Pet S260I (a catalytic site mutant) proteins. Pet, but not Pet S260I, could cleave C3, C5 and C9 components, and also inhibited the natural formation of C9 polymers. Furthermore, a dose-dependent inhibition of ZnCl2-induced C9 polymerization in vitro was observed. E. coli DH5α survived incubation with human serum pre-treated with Pet. Therefore, Pet can potentially interfere with the alternative and the terminal pathways of the complement system. In addition, by cleaving C9, Pet may inhibit membrane attack complex (MAC) formation on the bacterial outer membrane. Thus, our data are suggestive of a role of Pet in resistance of E. coli to human serum

XVI International Congress of Control Electronics and Telecommunications: "Techno-scientific considerations for a post-pandemic world intensive in knowledge, innovation and sustainable local development"

Este título, sugestivo por los impactos durante la situación de la Covid 19 en el mundo, y que en Colombia lastimosamente han sido muy críticos, permiten asumir la obligada superación de tensiones sociales, políticas, y económicas; pero sobre todo científicas y tecnológicas. Inicialmente, esto supone la existencia de una capacidad de la sociedad colombiana por recuperar su estado inicial después de que haya cesado la perturbación a la que fue sometida por la catastrófica pandemia, y superar ese anterior estado de cosas ya que se encontraban -y aún se encuentran- muchos problemas locales mal resueltos, medianamente resueltos, y muchos sin resolver: es decir, habrá que rediseñar y fortalecer una probada resiliencia social existente - producto del prolongado conflicto social colombiano superado parcialmente por un proceso de paz exitoso - desde la tecnociencia local; como lo indicaba Markus Brunnermeier - economista alemán y catedrático de economía de la Universidad de Princeton- en su libro The Resilient Society…La cuestión no es preveerlo todo sino poder reaccionar…aprender a recuperarse rápido.This title, suggestive of the impacts during the Covid 19 situation in the world, and which have unfortunately been very critical in Colombia, allows us to assume the obligatory overcoming of social, political, and economic tensions; but above all scientific and technological. Initially, this supposes the existence of a capacity of Colombian society to recover its initial state after the disturbance to which it was subjected by the catastrophic pandemic has ceased, and to overcome that previous state of affairs since it was found -and still is find - many local problems poorly resolved, moderately resolved, and many unresolved: that is, an existing social resilience test will have to be redesigned and strengthened - product of the prolonged Colombian social conflict partially overcome by a successful peace process - from local technoscience; As Markus Brunnermeier - German economist and professor of economics at Princeton University - indicates in his book The Resilient Society...The question is not to foresee everything but to be able to react...learn to recover quickly.Bogot

Winogradsky Bioelectrochemical System as a Novel Strategy to Enrich Electrochemically Active Microorganisms from Arsenic-Rich Sediments

Bioelectrochemical systems (BESs) have been extensively studied for treatment and remediation. However, BESs have the potential to be used for the enrichment of microorganisms that could replace their natural electron donor or acceptor for an electrode. In this study, Winogradsky BES columns with As-rich sediments extracted from an Andean watershed were used as a strategy to enrich lithotrophic electrochemically active microorganisms (EAMs) on electrodes (i.e., cathodes). After 15 months, Winogradsky BESs registered power densities up to 650 μWcm−2. Scanning electron microscopy and linear sweep voltammetry confirmed microbial growth and electrochemical activity on cathodes. Pyrosequencing evidenced differences in bacterial composition between sediments from the field and cathodic biofilms. Six EAMs from genera Herbaspirillum, Ancylobacter, Rhodococcus, Methylobacterium, Sphingomonas, and Pseudomonas were isolated from cathodes using a lithoautotrophic As oxidizers culture medium. These results suggest that the tested Winogradsky BES columns result in an enrichment of electrochemically active As-oxidizing microorganisms. A bioelectrochemical boost of centenarian enrichment approaches, such as the Winogradsky column, represents a promising strategy for prospecting new EAMs linked with the biogeochemical cycles of different metals and metalloids

Winogradsky Bioelectrochemical System as a Novel Strategy to Enrich Electrochemically Active Microorganisms from Arsenic-Rich Sediments

Bioelectrochemical systems (BESs) have been extensively studied for treatment and remediation. However, BESs have the potential to be used for the enrichment of microorganisms that could replace their natural electron donor or acceptor for an electrode. In this study, Winogradsky BES columns with As-rich sediments extracted from an Andean watershed were used as a strategy to enrich lithotrophic electrochemically active microorganisms (EAMs) on electrodes (i.e., cathodes). After 15 months, Winogradsky BESs registered power densities up to 650 μWcm−2. Scanning electron microscopy and linear sweep voltammetry confirmed microbial growth and electrochemical activity on cathodes. Pyrosequencing evidenced differences in bacterial composition between sediments from the field and cathodic biofilms. Six EAMs from genera Herbaspirillum, Ancylobacter, Rhodococcus, Methylobacterium, Sphingomonas, and Pseudomonas were isolated from cathodes using a lithoautotrophic As oxidizers culture medium. These results suggest that the tested Winogradsky BES columns result in an enrichment of electrochemically active As-oxidizing microorganisms. A bioelectrochemical boost of centenarian enrichment approaches, such as the Winogradsky column, represents a promising strategy for prospecting new EAMs linked with the biogeochemical cycles of different metals and metalloids

PRESSURE AND PRESSURE DERIVATIVE ANALYSIS FOR NON-NEWTONIAN PSEUDOPLASTIC FLUIDS IN DOUBLE-POROSITY FORMATIONS

ABSTRACT Non-Newtonian fluids are often used during various drilling, workover and enhanced oil recovery processes. Most of the fracturing fluids injected into reservoir-bearing formations possess non- Newtonian nature and these fluids are often approximated by Newtonian fluid flow models. In the field of well testing, several analytical and numerical models based on Bingham, pseudoplastic and dilatant non-Newtonian behavior, have been introduced in the literature to study their transient nature in porous media for a better reservoir characterization. Most of them deal with fracture wells and homogeneous formations. Well test interpretation is conducted via the straight-line conventional analysis or type-curve matching. Only a few studies consider the pressure derivative analysis. However, there is a need for a more practical and accurate way of characterizing such systems. So far, there is no methodology to characterize heterogeneous formation bearing non-Newtonian fluids through well test analysis. In this study, an interpretation methodology using the pressure and pressure derivative log-log plot is presented for non-Newtonian fluids in naturally fractured formations. The dimensionless fracture storativity ratio, omega, and interporosity flow parameter, lambda, are obtained from characteristics points found on such plot. The developed equations and correlations are successfully verified by their application only to synthetic well test data since no actual field data are available. A good match is found between the results provided by the proposed technique and the values used to generate the simulated data.RESUMEN Los fluidos no Newtonianos se usan a menudo en varios procesos de perforación, trabajo a pozos y actividades de recobro mejorado. La mayoría de los fluidos de fracturamiento inyectados en los yacimientos que contienen hidrocarburos se comportan no Newtoniamente y, sin embargo, estos fluidos comúnmente se representan en los modelos como modelos fluidos Newtonianos. En el campo de pruebas de presión, se han desarrollado varios modelos numéricos y analíticos que tienen en cuenta el comportamiento no Newtoniano Bingham, pseudoplá;stico y dilatante, para estudiar la naturaleza transitoria de estos fluidos en una mejor caracterizacion del yacimiento. Se han propuesto varios modelos numericos y analiticos para estudiar el comportamiento transitorio de los fluidos no Newtonianos en medios porosos. La mayoría de ellos tratan pozos fracturados y formaciones homogeneas y la interpretacion de los datos de presion se conduce mediante el metodo convencional de la linea recta o ajuste por curvas tipo. Solamente unos pocos estudios consideran analisis con la derivada de presion. Hasta ahora no existe ninguna metodologia para caracterizar formaciones heterogeneas mediante pruebas de presion. Sin embargo, hay necesidad de una forma mas practica y exacta de caracterizar estos sistemas. Por lo tanto, este trabajo presenta una metodologia de interpretacion usando la curva logaritmica de presion y derivada de presion para fluidos no Newtonianos en formaciones naturalmente fracturadas de modo que el coeficiente adimensional de almacenaje, omega, y el parametro de flujo interporoso, lambda, se obtienen de puntos caracteristicos encontrados en el grafico log-log de la presion y derivada de presión. Las ecuaciones y correlaciones desarrolladas se verificaron satisfactoriamente mediante su aplicación solo a pruebas de presion sinteticas ya que no existen datos reales reportados en la literatura. Se hallo un buen ajuste entre los resultados obtenidos mediante la metodologia propuesta y los valores usados para generar la simulación.RESUMO O fluidos não Newtonianos são usados frequentemente em vá;rios processos de perfuração, trabalho em poços e atividades de recuperação melhorada. A maioria dos fluidos de fraturamento injetados nas jazidas que contêm hidrocarbonetos se comportam não Newtoniamente e, não obstante, estes fluidos são representados normalmente nos modelos como modelos fluidos Newtonianos. No campo de provas de pressão, foram desenvolvidos vá;rios modelos numéricos e analíticos que consideram o comportamento não Newtoniano Bingham, pseudoplá;stico e dilatante para estudar a natureza transitória destes fluidos para uma melhor caracterização da jazida. Foram propostos vá;rios modelos numéricos e analíticos para estudar o comportamento transitório dos fluidos não Newtonianos em meios porosos. A maioria deles trata poços fraturados e formações homogêneas e a interpretação dos dados de pressão é conduzida mediante o método convencional da linha reta ou ajuste por curvas tipo. Apenas uns poucos estudos consideram aná;lise com a derivada de pressão. Até agora não existe nenhuma metodologia para caracterizar formações heterogêneas mediante provas de pressão. Porém, existe a necessidade de uma forma mais prá;tica e exata de caracterizar estes sistemas. Por tanto, este trabalho apresenta uma metodologia de interpretação usando a curva logarítmica de pressão e derivada de pressão para fluidos não Newtonianos em formações naturalmente fraturadas, de modo que o coeficiente adimensional de armazenamento, ômega, e o parâmetro de fluxo interporoso, lambda, são obtidos de pontos característicos encontrados no grá;fico log-log da pressão e da derivada de pressão. As equações e correlações desenvolvidas foram consideradas satisfatórias mediante sua aplicação individual a provas de pressão sintéticas, já; que não existem dados reais registrados na literatura. Encontrou-se um bom ajuste entre os resultados obtidos mediante a metodologia proposta e os valores usados para gerar a simulação

Pressure and pressure derivative analysis for non-newtonian pseudoplastic fluids in double-porosity formations

Non-Newtonian fluids are often used during various drilling, workover and enhanced oil recovery processes. Most of the fracturing fluids injected into reservoir-bearing formations possess non- Newtonian nature and these fluids are often approximated by Newtonian fluid flow models. In the field of well testing, several analytical and numerical models based on Bingham, pseudoplastic and dilatant non-Newtonian behavior, have been introduced in the literature to study their transient nature in porous media for a better reservoir characterization. Most of them deal with fracture wells and homogeneous formations. Well test interpretation is conducted via the straight-line conventional analysis or type-curve matching. Only a few studies consider the pressure derivative analysis. However, there is a need for a more practical and accurate way of characterizing such systems. So far, there is no methodology to characterize heterogeneous formation bearing non-Newtonian fluids through well test analysis. In this study, an interpretation methodology using the pressure and pressure derivative log-log plot is presented for non-Newtonian fluids in naturally fractured formations. The dimensionless fracture storativity ratio, ù, and interporosity flow parameter, ë, are obtained from characteristics points found on such plot. The developed equations and correlations are successfully verified by their application only to synthetic well test data since no actual field data are available. A good match is found between the results provided by the proposed technique and the values used to generate the simulated data.O fluidos nao Newtonianos sao usados frequentemente em varios processos de perfuracao, trabalho em pocos e atividades de recuperacao melhorada. A maioria dos fluidos de fraturamento injetados nas jazidas que contem hidrocarbonetos se comportam nao Newtoniamente e, nao obstante, estes fluidos sao representados normalmente nos modelos como modelos fluidos Newtonianos. No campo de provas de pressao, foram desenvolvidos varios modelos numericos e analiticos que consideram o comportamento nao Newtoniano Bingham, pseudoplastico e dilatante para estudar a natureza transitoria destes fluidos para uma melhor caracterizacao da jazida. Foram propostos varios modelos numericos e analiticos para estudar o comportamento transitorio dos fluidos nao Newtonianos em meios porosos. A maioria deles trata pocos fraturados e formacoes homogeneas e a interpretacao dos dados de pressao e conduzida mediante o metodo convencional da linha reta ou ajuste por curvas tipo. Apenas uns poucos estudos consideram analise com a derivada de pressao. Ate agora nao existe nenhuma metodologia para caracterizar formacoes heterogeneas mediante provas de pressao. Porem, existe a necessidade de uma forma mais pratica e exata de caracterizar estes sistemas. Portanto, este trabalho apresenta uma metodologia de interpretacao usando a curva logaritmica de pressao e derivada de pressao para fluidos nao Newtonianos em formacoes naturalmente fraturadas, de modo que o coeficiente adimensional de armazenamento, w, e o parametro de fluxo interporoso, �É, sao obtidos de pontos caracteristicos encontrados no grafico log-log da pressao e da derivada de pressao. As equacoes e correlacoes desenvolvidas foram consideradas satisfatorias mediante sua aplicacao individual a provas de pressao sinteticas, ja que nao existem dados reais registrados na literatura. Encontrou-se um bom ajuste entre os resultados obtidos mediante a metodologia proposta e os valores usados para gerar a simulacao.L os fluidos no Newtonianos se usan a menudo en varios procesos de perforacion, trabajo a pozos y actividades de recobro mejorado. La mayoria de los fluidos de fracturamiento inyectados en los yacimientos que contienen hidrocarburos se comportan no Newtoniamente y, sin embargo, estos fluidos comunmente se representan en los modelos como modelos fluidos Newtonianos. En el campo de pruebas de presion, se han desarrollado varios modelos numericos y analiticos que tienen en cuenta el comportamiento no Newtoniano Bingham, pseudoplastico y dilatante, para estudiar la naturaleza transitoria de estos fluidos en una mejor caracterizacion del yacimiento. Se han propuesto varios modelos numericos y analiticos para estudiar el comportamiento transitorio de los fluidos no Newtonianos en medios porosos. La mayoria de ellos tratan pozos fracturados y formaciones homogeneas y la interpretacion de los datos de presion se conduce mediante el metodo convencional de la linea recta o ajuste por curvas tipo. Solamente unos pocos estudios consideran analisis con la derivada de presion. Hasta ahora no existe ninguna metodologia para caracterizar formaciones heterogeneas mediante pruebas de presion. Sin embargo, hay necesidad de una forma mas practica y exacta de caracterizar estos sistemas. Por lo tanto, este trabajo presenta una metodologia de interpretacion usando la curva logaritmica de presion y derivada de presion para fluidos no Newtonianos en formaciones naturalmente fracturadas de modo que el coeficiente adimensional de almacenaje, w, y el parametro de flujo interporoso, �É, se obtienen de puntos caracteristicos encontrados en el grafico log-log de la presion y derivada de presion. Las ecuaciones y correlaciones desarrolladas se verificaron satisfactoriamente mediante su aplicacion solo a pruebas de presion sinteticas ya que no existen datos reales reportados en la literatura. Se hallo un buen ajuste entre los resultados obtenidos mediante la metodologia propuesta y los valores usados para generar la simulacion