Simple Protocol for Secondary School Hands-On Activity: Electrophoresis of Pre-Stained Nucleic Acids on Agar-Agar Borate Gels

An extremely simple, inexpensive, and safe method is presented, which emulates nucleic acids isolation and electrophoretic analysis as performed in a research environment, in the context of a secondary school hands-on activity. The protocol is amenable to an interdisciplinary approach, taking into consideration the electrical and chemical parameters of the electrophoretic system. Furthermore, the laboratory is framed in a more comprehensive pedagogical setting, which addresses the methodological aspects of a pivotal scientific enterprise such as the Human Genome Project. In this setting, the hands-on activity is complemented with animations, paper models, and discussions. Additionally, our results indicate that the use of borate buffer and agar-agar gels suits many of the experiments included in college-level laboratory activities, which currently make use of more expensive agarose gels and TBE or TAE buffer

Integración de recursos del paradigma analítico y de la inteligencia de negocios como estrategia para el fortalecimiento del proceso de toma de decisiones en un contexto educativo

El desarrollo de las tecnologías de información y comunicación han facilitado el uso de herramientas tecnológicas en numerosos ámbitos. Esto ha propiciado la generación de información en volúmenes significativos, que dificulta la posibilidad de extraer decisiones basadas en situaciones detectadas como no deseables. Es por eso que las organizaciones necesitan la integración de herramientas tecnológicas adecuadas para poder adaptarse a las exigencias del medio y detectar de manera más ágil las posibilidades de mejora. Por lo tanto este proyecto pretende el desarrollo de una metodología para el diseño de un sistema de soporte decisión que será aplicado en un contexto educativo.Eje: Tecnología Informática Aplicada en Educación.Red de Universidades con Carreras en Informátic

Integración de recursos del paradigma analítico y de la inteligencia de negocios como estrategia para el fortalecimiento del proceso de toma de decisiones en un contexto educativo

El desarrollo de las tecnologías de información y comunicación han facilitado el uso de herramientas tecnológicas en numerosos ámbitos. Esto ha propiciado la generación de información en volúmenes significativos, que dificulta la posibilidad de extraer decisiones basadas en situaciones detectadas como no deseables. Es por eso que las organizaciones necesitan la integración de herramientas tecnológicas adecuadas para poder adaptarse a las exigencias del medio y detectar de manera más ágil las posibilidades de mejora. Por lo tanto este proyecto pretende el desarrollo de una metodología para el diseño de un sistema de soporte decisión que será aplicado en un contexto educativo.Eje: Tecnología Informática Aplicada en Educación.Red de Universidades con Carreras en Informátic

Regulatory Response to Carbon Starvation in Caulobacter crescentus

Bacteria adapt to shifts from rapid to slow growth, and have developed strategies for long-term survival during prolonged starvation and stress conditions. We report the regulatory response of C. crescentus to carbon starvation, based on combined high-throughput proteome and transcriptome analyses. Our results identify cell cycle changes in gene expression in response to carbon starvation that involve the prominent role of the FixK FNR/CAP family transcription factor and the CtrA cell cycle regulator. Notably, the SigT ECF sigma factor mediates the carbon starvation-induced degradation of CtrA, while activating a core set of general starvation-stress genes that respond to carbon starvation, osmotic stress, and exposure to heavy metals. Comparison of the response of swarmer cells and stalked cells to carbon starvation revealed four groups of genes that exhibit different expression profiles. Also, cell pole morphogenesis and initiation of chromosome replication normally occurring at the swarmer-to-stalked cell transition are uncoupled in carbon-starved cells

Snorkeling to Deep Sea Diving: Helping Students Take the Plunge into Ambiguity

Today’s world is an ocean of ambiguity. Explore how to design learning experiences that will help your students (and you) confidently take the plunge

Snorkeling to Deep Sea Diving: Helping Students Take the Plunge into Ambiguity

Today’s world is an ocean of ambiguity. Explore how to design learning experiences that will help your students (and you) confidently take the plunge

CrfA, a Small Noncoding RNA Regulator of Adaptation to Carbon Starvation in Caulobacter crescentus▿ †

Small noncoding regulatory RNAs (sRNAs) play a key role in the posttranscriptional regulation of many bacterial genes. The genome of Caulobacter crescentus encodes at least 31 sRNAs, and 27 of these sRNAs are of unknown function. An overexpression screen for sRNA-induced growth inhibition along with sequence conservation in a related Caulobacter species led to the identification of a novel sRNA, CrfA, that is specifically induced upon carbon starvation. Twenty-seven genes were found to be strongly activated by CrfA accumulation. One-third of these target genes encode putative TonB-dependent receptors, suggesting CrfA plays a role in the surface modification of C. crescentus, facilitating the uptake of nutrients during periods of carbon starvation. The mechanism of CrfA-mediated gene activation was investigated for one of the genes predicted to encode a TonB-dependent receptor, CC3461. CrfA functions to stabilize the CC3461 transcript. Complementarity between a region of CrfA and the terminal region of the CC3461 5′-untranslated region (5′-UTR) and also the behavior of a deletion of this region and a site-specific base substitution and a 3-base deletion in the CrfA complementary sequence suggest that CrfA binds to a stem-loop structure upstream of the CC3461 Shine-Dalgarno sequence and stabilizes the transcript

Cyanobacteria and cyanotoxins in freshwaters of Uruguay

Cyanobacterial blooms are a worldwide environmental problem. This phenomenon is typically associated with eutrophication (nutrient enrichment) and changes in hydrology. In this study we analysed the distribution of planktonic cyanobacteria in Uruguay and their toxins (microcystin, saxitoxin and cylindrospermopsin), working with an interagency team (OSE, DINAMA, IM, University of the Republic and IIBCE). An historical data base (n = 3061 for 64 ecosystems, years 1980-2014) was generated. Differences between lotic and lentic ecosystems were found in terms of chlorophyll a and nutrient concentrations, usually indicating eutrophication. Two geo-referenced maps for the country were generated with cyanobacteria biomass indicators and the most relevant toxin (microcystin), according to risk levels suggested by the World Health Organization for recreational waters. The areas of greatest risk of exposure were the reservoirs of large rivers (Uruguay and Río Negro) and Río de la Plata beaches. In the second part of the study, up to 20 mg L-1of microcystin was quantified in bloom (scum) samples, as well as the presence of genes that suggest more microcystin varieties, potentially with greater toxicity. This study provides basic information about the distribution of cyanobacteria in Uruguayan freshwaters that will be useful for national monitoring programs and scientific research

Cianobacterias y cianotoxinas en ecosistemas límnicos de Uruguay

Cyanobacterial blooms are a worldwide environmental problem. This phenomenon is typically associated with eutrophication (nutrient enrichment) and changes in hydrology. In this study we analysed the distribution of planktonic cyanobacteria in Uruguay and their toxins (microcystin, saxitoxin and cylindrospermopsin), working with an interagency team (OSE, DINAMA, IM, University of the Republic and IIBCE). An historical data base (n = 3061 for 64 ecosystems, years 1980-2014) was generated. Differences between lotic and lentic ecosystems were found in terms of chlorophyll a and nutrient concentrations, usually indicating eutrophication. Two geo-referenced maps for the country were generated with cyanobacteria biomass indicators and the most relevant toxin (microcystin), according to risk levels suggested by the World Health Organization for recreational waters. The areas of greatest risk of exposure were the reservoirs of large rivers (Uruguay and Río Negro) and Río de la Plata beaches. In the second part of the study, up to 20 mg L-1of microcystin was quantified in bloom (scum) samples, as well as the presence of genes that suggest more microcystin varieties, potentially with greater toxicity. This study provides basic information about the distribution of cyanobacteria in Uruguayan freshwaters that will be useful for national monitoring programs and scientific research.Las floraciones de cianobacterias en cuerpos de agua dulce constituyen un problema mundial, asociado a la eutrofización (enriquecimiento de nutrientes) y cambios hidrológicos de los ecosistemas. En este estudio se generó una base de datos históricos (n= 3061 para 64 ecosistemas, de 1980 a 2014), elaborada por un grupo de trabajo interinstitucional (OSE, DINAMA, IM, Universidad de la República e IIBCE), y se analizó la distribución de cianobacterias planctónicas y de cianotoxinas (microcistina, saxitoxina y cilindrospermopsina) en Uruguay. Los valores de clorofila ay nutrientes totales indicaron procesos de eutrofización en diversos ecosistemas. En dos mapas georreferenciados se visualiza la distribución de cianobacterias en el país, según indicadores cuantitativos globales, y de la microcistina (cianotoxina más frecuente). En dichos mapas se destacan los embalses (Río   Uruguay y Río Negro) y las playas del Río de la Plata como las zonas de mayor riesgo de exposición a cianobacterias según las categorías de la Organización Mundial de la Salud para aguas recreacionales. Además, se analizaron muestras de floraciones (espuma) y se cuantificó 20 mg L-1de microcistinas totales y la presencia de genes que sugieren diferentes variedades de microcistinas. Se generó información básica que podrá ser útil para programas de monitoreo nacionales e investigación