1,440 research outputs found
Las interacciones mediáticas de la juventud boliviana: la competencia mediática de jóvenes de La Paz
Se analizan los resultados de una investigación cualitativa en torno a los hábitos de consumo audiovisual y la competencia mediática de la juventud boliviana en la ciudad de La Paz. Los resultados del estudio muestran que la juventud de La Paz consume preferentemente programas televisivos, aunque se extiende con fuerza el uso de Internet, la telefonía móvil y los videojuegos, siendo los medios menos usados la radio y la prensa escrita. A pesar de percibirse como personas críticas, los jóvenes entrevistados muestran carencias en la importancia y necesidad de la educación mediática y de mayor reflexión acerca de los medios
Experimental VLE data of methyl acetate or ethyl acetate + 1-butanol at 0.6 MPa. Predictions with Peng-Robinson EOS and group contribution models
Vapor-liquid equilibrium data were obtained with a stainless steel ebulliometer at 0.6 MPa for methyl acetate + 1-butanol and ethyl acetate + 1-butanol. The experimental data for the binary systems were tested and verified thermodynamically, showed positive consistency when the point-to-point test of Van Nesswas applied. The group contribution models ASO Gand three versions of the UNIFAC were applied to calculate the vapor-liquid equilibrium data and after, these values were compared to the experimental data.The approach f-f was applied by using the Peng-Robinson equation of state, the classical attractive term was employed. The quadratic and Wong-Sandler mixing rules were verified and the adjustable parameter of Stryjek-Vera was also applied
Phosphomannosylation and the functional analysis of the extended Candida albicans MNN4-like gene family
We thank Luz A. López-Ramírez (Universidad de Guanajuato) for technical assistance. This work was supported by Consejo Nacional de Ciencia y Tecnología (ref. CB2011/166860; PDCPN2014-247109, and FC 2015-02-834), Universidad de Guanajuato (ref. 000025/11; 0087/13; ref. 1025/2016; Convocatoria Institucional para Fortalecer la Excelencia Académica 2015; CIFOREA 89/2016), Programa de Mejoramiento de Profesorado (ref. UGTO-PTC-261), and Red Temática Glicociencia en Salud (CONACYT-México). NG acknowledges the Wellcome Trust (086827, 075470, 101873, and 200208) and MRC Centre for Medical Mycology for funding (N006364/1). KJ was supported by a research visitor grant to Aberdeen from China Scholarship Council (CSC No. 201406055024). The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmicb.2017.02156/full#supplementary-materialPeer reviewedPublisher PD
Sowing density effect on common bean leaf area development
Sowing density is a major management factor that affects growth and development of grain crops by modifying the canopy light environment and interplant competition for water and nutrients. While the effects of sowing density and plant architecture on static vegetative and reproductive growth traits have been explored previously in the common bean, few studies have focused on the impacts of sowing density on the dynamics of node addition and leaf area development. We present the results from two sites of field experiments where the effects of sowing densities (5, 10, 15, 20, 25 and 35 plants m-2) and genotypes with contrasting plant architectures (two each from growth habits I through III) on the dynamics of node addition and leaf area were assessed. Analysis of the phyllochron (°C node-1) indicated genotype and density effects (but no interaction) on the rate of node addition. While significant, these differences amounted to less than two days of growth at either site. In terms of leaf area development, analysis using a power function reflected large differences in the dynamics and final size of individual plant leaf area between the lower density (20 plants m-2) at the growth habit, but not genotype level. These differences in node addition and leaf development dynamics translated to marked differences between growth habits and sowing densities in estimated leaf area indices, and consequently, in the estimated fraction of intercepted light at lower densities
Upstream dam impacts on gilded catfish Brachyplatystoma rousseauxii (Siluriformes: Pimelodidae) in the Bolivian Amazon
This paper explores the effects of two run-of-river dams (Jirau and Santo Antônio) built in cascade in the middle Madeira River (Brazil) on the interruption of long-distance migration routes of the gilded catfish (Brachyplatystoma rousseauxii). A participative monitoring system was set up to compare capture by commercial fishers approximately 1500 km upstream ofthe dams in Bolivia, before (1998-2007) and after (2015-2017) dam closure. A significant decrease in gilded catfish catches and in catch per unit effort was observed after dam closure, whereas no significant difference in mean weight was found. Back-estimation of age suggests that the few individuals remaining after dam closure in 2009 are a mixture of old homers that returned upstream before dam closure, and residents hatched after dam closure and trapped in the upper Madeira. Unless fishways in the Madeira River dams improve their efficiency, the gilded catfish might become rare and in danger of regional extinction in the upper Madeira basin in the next few years, negatively affecting river fisheries.Fil: Van Damme, Paul A.. Instituto de Investigación Aplicada de Recursos Acuáticos; Bolivia. Universidad Mayor de San Simón; BoliviaFil: Córdova Clavijo, Leslie. Instituto de Investigación Aplicada de Recursos Acuáticos; BoliviaFil: Baigún, Claudio Rafael M.. Universidad Nacional de San Martín. Instituto de Investigación e Ingeniería Ambiental. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación e Ingeniería Ambiental; ArgentinaFil: Hauser, Marilia. Universidade Federal de Rondônia; Brasil. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; FranciaFil: da Costa Doria, Carolina R.. Centre National de la Recherche Scientifique. Institut de Recherche pour le Développement; Francia. Universidade Federal de Rondônia; BrasilFil: Duponchelle, Fabrice. Universidade Federal de Rondônia; Brasi
TMEM16A calcium-activated chloride currents in supporting cells of the mouse olfactory epithelium
Glial-like supporting (or sustentacular) cells are important constituents of the olfactory epithelium that are involved in several physiological processes such as production of endocannabinoids, insulin, and ATP and regulation of the ionic composition of the mucus layer that covers the apical surface of the olfactory epithelium. Supporting cells express metabotropic P2Y purinergic receptors that generate ATP-induced Ca2+ signaling through the activation of a PLC-mediated cascade. Recently, we reported that a subpopulation of supporting cells expresses also the Ca2+-activated Cl- channel TMEM16A. Here, we sought to extend our understanding of a possible physiological role of this channel in the olfactory system by asking whether Ca2+ can activate Cl- currents mediated by TMEM16A. We use whole-cell patch-clamp analysis in slices of the olfactory epithelium to measure dose-response relations in the presence of various intracellular Ca2+ concentrations, ion selectivity, and blockage. We find that knockout of TMEM16A abolishes Ca2+-activated Cl- currents, demonstrating that TMEM16A is essential for these currents in supporting cells. Also, by using extracellular ATP as physiological stimuli, we found that the stimulation of purinergic receptors activates a large TMEM16A-dependent Cl- current, indicating a possible role of TMEM16A in ATP-mediated signaling. Altogether, our results establish that TMEM16A-mediated currents are functional in olfactory supporting cells and provide a foundation for future work investigating the precise physiological role of TMEM16A in the olfactory system
Una nueva especie de costus (costaceae) de la amazonia colombiana
Se describe e ilustra Costus fissicalyx N. R. Salinas, Clavijo and amp; Betancur, una especienueva del sudeste de la Amazonia colombiana; además, se presenta información sobresus relaciones taxonómicas, distribución y hábitat. Costus fissicalyx se diferencia delas otras especies del género principalmente por la forma y el tipo de crecimientodel cáli
Cross-flow filtration for the recovery of lipids from microalgae aqueous extracts: membrane selection and performances
International audienceThe biorefinery of microalgae necessitates innovative choices of soft and energy-efficient processes to guarantee the integrity of fragile molecules and develop eco-friendly production. A wet processing of biomass is proposed, which avoids expensive drying steps. It includes harvesting, cell disruption, and fractionation of the target compounds. Membrane filtration is a promising clean fractionation step. In this paper, the recovery of lipids from starving Parachlorella kessleri aqueous extracts by cross-flow filtration was studied. A model solution was formulated to test four membranes of different materials (PVDF, PES, PAN) and cut-offs (200 kDa - 1.5 µm). The hydrophilic PAN 500kDa membrane presented the best performance (flux stability, permeate flux, lipid retention, and cleanability) and was therfore selected for filtrating real aqueous extracts. Similar permeation fluxes were obtained with model and real products: 34 -41Lh-1m-2 respectively. The coalescence of lipid droplets was observed with model solutions but not with real products, less concentrated. The lipids from the real products were wholly retained by the PAN membrane, whereas some of the polysaccharides and proteins were able to permeate. An optimization of the coupling between culture, cell disruption, clarification, and filtration would allow a good concentration and purification of the lipids from microalgae
TMEM16A and TMEM16B modulate pheromone-evoked action potential firing in mouse vomeronasal sensory neurons
The mouse vomeronasal system controls several social behaviors. Pheromones and other social cues are detected by sensory neurons in the vomeronasal organ (VNO). Stimuli activate a transduction cascade that leads to membrane potential depolarization, increase in cytosolic Ca2+ level, and increased firing. The Ca2+-activated chloride channels TMEM16A and TMEM16B are co-expressed within microvilli of vomeronasal neurons, but their physiological role remains elusive. Here, we investigate the contribution of each of these channels to vomeronasal neuron firing activity by comparing wild-type (WT) and knock-out (KO) mice. Performing loosepatch recordings from neurons in acute VNO slices, we show that spontaneous activity is modified by Tmem16a KO, indicating that TMEM16A, but not TMEM16B, is active under basal conditions. Upon exposure to diluted urine, a rich source of mouse pheromones, we observe significant changes in activity. Vomeronasal sensory neurons (VSNs) from Tmem16a cKO and Tmem16b KO mice show shorter interspike intervals (ISIs) compared with WT mice, indicating that both TMEM16A and TMEM16B modulate the firing pattern of pheromone-evoked activity in VSNs
4. SISTEMA INTEGRADO DE GESTIÓN DE LA INFORMACIÓN WEB PARA EJECUCIÓN DE PROCESOS DE EVALUACIÓN SOBRE MANTENIMIENTO CORRECTIVO Y FALLAS DE MAQUINARIA INDUSTRIAL
Las tecnologías de la información y de la comunicación (TIC’s), han fortalecido la transformación y evolución sistemática de las empresas, produciendo variantes trascendentales en el uso de las nuevas tecnologías y el impulso hacia la tendencia de innovar en los ámbitos del sector económico, productivo y social. En el área de mantenimiento muchas empresas llevan sus registros en papel o en software no especializado y aunque tienen la información, no pueden acceder fácilmente a registros históricos, ni a registros estadísticos sobre su gestión y muchas veces esta información está dispersa, restándoles competitividad. La plataforma propuesta (SIGIVEC) permite solventar en gran medida estas limitaciones sirviendo como la entrada a la cultura de registro sistemático, en tiempo real y descentralizado, aprovechando las TIC’s para realizar inicialmente el registro de los eventos correctivos para que a partir de bases de datos e indicadores el usuario puede indicadores el usuario puede revisar fácilmente casos similares ocurrido en su empresa, soluciones, recursos, costos, etc, llevándolo a implementar acciones de mejora continua por medio de indicadores medibles para, reducir costos de mantenimiento, vigilar los procesos de mantenimiento y la formulación de análisis en la toma de decisión y sus etapas de desarrollo industrial y permitirle a la empresa pensar en la generación de una cultura de mantenimiento preventivo. Adicionalmente la plataforma funciona como un observatorio tecnológico para el SENA, este ahorra tiempo administrativo en recolectar información, clasificar, analizar y comunicar al sector público y privado información índole general relacionada con mantenimiento, también es un insumo que le permite entre otras direccionar los diseños curriculares de los programas de formación relacionados con mantenimiento. El concepto de software de mantenimiento actual evolucionaría a la tecnología de Big Data en la Nube y sería parte de la revolución industrial conocida como Industria 4.0 enfocado en el intercambio de datos
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