Detection, quantification, and characterization of polystyrene microplastics and adsorbed bisphenol A contaminant using electroanalytical techniques

The potential applications of electroanalytical techniques for the quantification and size characterization of nonelectroactive polystyrene microplastics is reported, in addition to characterizing the kinetics of adsorption of bisphenol A on these polystyrene microparticles. The individual adsorption events of very diluted polystyrene microparticles dispersions on glassy-carbon microelectrodes produce the blocking of the charge transfer of a mediator (ferrocene-methanol) thus decreasing the current of the recorded chronoamperogram in a stepwise manner. The magnitude of the current steps are in the order of pA values and can be related to the diameter of the plastic microparticles in the size range 0.1 to 10 µm. The frequency of the current steps in the domain time used (120 s) allows to quantify the number concentration of these microparticles in the range 0.005 to 0.500 pM. Electrochemical impedance spectroscopy confirms the adsorption of the polystyrene microplastics on carbon microelectrodes (and to a lesser extent on platinum microelectrodes) under the same experimental conditions as above. On the other hand, the adsorbed microplastics become concentrators of other pollutants found in the environment. The sensitive differential-pulse voltammetry determination of bisphenol A (linear range 0.80–15.00 µM; detection limit 0.24 µM) was used together with a simple separation procedure for studying the adsorption of bisphenol A on polystyrene microparticles. The adsorption capacity (mg of bisphenol A retained per g of the polystyrene microplastics) decreased from approximately 5.7 to 0.8 mg g−1 with increasing dosages of polystyrene microparticles from 0.2 to 1.6 g l−1. The adsorption isotherms were modeled resulting in a monolayer of bisphenol A adsorbed on the microplastics (i.e., best fitted to a Langmuir model)

Diseño de un modelo de vivienda bioclimática y sostenible. Fase II

El presente documento busca retroalimentar la propuesta de vivienda planteada en la primera fase de la investigación, por medio de un experimento en el cual se midieron datos de temperatura y humedad relativa en modelos a escala hechos con tres sistemas constructivos livianos diferentes. De esta forma es posible determinar cuál sistema constructivo es más apto para las distintas condiciones climáticas que se presentan en el país, de acuerdo con las características propias de cada sitio. La investigación se complementa con una profundización de los elementos que deben ser tomados en cuenta en el diseño de una vivienda que satisfaga las necesidades básicas y la aplicación del diseño bioclimático, proponiendo modelos conceptuales que contienen alternativas tecnológicas y se analiza su factibilidad de aplicación. Se presentan, además, un breve análisis de la legislación salvadoreña en cuanto a la construcción de viviendas y aspectos básicos de la vivienda de interés social en el país, planteando un análisis que pretende superar la visión economicista para resaltar la importancia de la participación de las personas para la contextualización de las propuestas y satisfacción de necesidades.La presente investigación fue subvencionada por la Universidad Tecnológica de El Salvador y contó con la colaboración delos estudiantes Madeline Recinos Hidalgo y José Roberto Galeano, de la carrera de Diseño Gráfico; y Víctor Ernesto Castro Martínez, de la carrera de Arquitectura. Las solicitudes de información, separatas y otros documentos relativos al presente estudio pueden hacerse a la dirección postal: calle Arce, 1020, Universidad Tecnológica de El Salvador, Vicerrectoría de Investigación, Dirección de Investigaciones, calle Arce y 17ª.avenida Norte, edificio José Martí, 2ª planta, o al correo electrónico: [email protected] Tecnológica de El Salvado

Techos ecológicos en vivienda multifamiliar como opción de preservación del medio ambiente

La presente investigación trata de definir los criterios necesarios para implantar techos ecológicos y variantes de ellos en edificios de vivienda multifamiliar ya existentes, específicamente en el área metropolitana de San Salvador. Partiendo de los beneficios que las cubiertas ajardinadas tienen, esta solución se ve desde el punto de vista de contribuir al balance de las actividades climatológicas, como generar una superficie que absorba el exceso de agua pluvial para así reducir el potencial de inundaciones y también como barreras de los distintos elementos contaminantes del aire, propios de la ciudad. Con base en las características físicas y climatológicas y su historia en cuanto a fenómenos naturales en San Salvador y cómo estos han afectado a la ciudad, y cómo esta responde a ellos, se plantean tres soluciones distintas, con la intención de reducir los efectos nocivos del constante crecimiento de la ciudad y las actitudes tomadas ante ello.La presente investigación fue subvencionada por la Universidad Tecnológica de El Salvador. Las solicitudes de información, separatas y otros documentos relativos al presente estudio pueden hacerlos a la dirección postal: calle Arce 1020, Universidad Tecnológica de El Salvador, Vicerrectoría de Investigación y Proyección Social, Dirección de Investigaciones, edificio José Martí, 2ª planta, o al correo electrónico [email protected] Tecnológica de El Salvado

Light with tunable non-Markovian phase imprint

We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and recording its diffraction pattern after a double slit: In both cases we observe instead of a central intensity maximum a line or cross shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Since these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serve as a testbed to gain a deeper understanding of non-Markovian processes

IT governance frameworks: A literature review of Brazilian publications

IT (Information Technology) governance has been a widely studied subject. This has generated different definitions and conceptual models to explain it. We conduct a concept-centric literature review based on a literature reference model. We used three literature frameworks to identify key-variables to evaluate and classify Brazilian IT governance publications. These variables were used to classify 90 Brazilian publications from 2004 to 2012. The authors chose Brazil due to its economic growth and companies’ internationalization on the last years. The organizations are fonder to regulatory and compliance marks due to market visibility, driving them towards IT governance practices due to growing dependence on IT. The frameworks used in the country are usually developed abroad - then verification on how they fit with Brazilian organizations is relevant to business management. The study shows that; the most used methodology is the case study; 90% of the papers were written in Portuguese; the IT alignment is cited, but not evaluated; few cases are related to small and medium business; and decision structures are not discussed. The authors conclude presenting a conceptual model summarizing all the models and Brazilian companies’ particularities

Firewood and timber exploitation during the third and second millennia BC in Northwestern Iberia: wood resources, territories and chaîne opératoire

Human societies established productive strategies in order to obtain the material resources needed for their day‐to‐day life, including firewood and timber. These strategies were determined by the environmental supply, and also by the cultural characteristics and technical capacities of these communities. This paper presents charcoal analysis data from four Chalcolithic and Bronze Age open‐air settlements located in the northwest of the Iberian Peninsula and occupied during the third and second millennia BC. These results contribute to the knowledge of the exploitation of wooden resources, of the territories where these resources were collected, and of the firewood and timber production process. The identified wood taxa point to a diversified exploitation of the territory, where firewood and timber were collected and/or felled in the deciduous woodland, the river banks and scrubland areas. The characteristics of the wood elements used, the degree of growth ring curvature, the minimum diameter of twigs or logs, etc., as well as other data from archaeological contexts, such as the length of the postholes, were all taken into account to establish hypotheses related to the operative chaine of forest resources. The wooden resources consumed in each site allowed us to hypothesize about the territory of each community.As sociedades humanas estabelecem toda uma série de estratégias produtivas destinadas a obter os meios materiais necessários para a sua existência, entre elas, o aprovisionamento de lenha e de madeira. Estas estratégias, além de estarem condicionadas pela oferta ambiental, são igualmente resultantes das caraterísticas culturais e das capacidades técnicas das comunidades. Os dados arqueobotânicos que se apresentam procedem de vários lugares de habitação do Calcolítico e da Idade do Bronze da fachada ocidental do Noroeste peninsular com cronologias que abarcam o 3º e parte do 2º milénios AC. Os resultados obtidos permitiram identificar uma exploração diversificada dos recursos lenhosos que combinava a recolha de lenha e de madeira da floresta climácica com a proveniente das áreas de mato. As formações arbóreas situadas nas margens dos cursos de água também constituíram fonte de aprovisionamento de combustíveis e, provavelmente, de madeira. A análise dendrológica das amostras registando o grau de curvatura dos anéis de crescimento anual, o diâmetro mínimo dos ramos ou troncos consumidos, entre outras características, em inter‑relação com determinados contextos arqueológicos (dimensões dos buracos de poste, por exemplo), proporcionaram hipóteses relacionadas com a cadeia técnica‑operativa dos recursos florestais. A caracterização dos recursos usados em cada um dos casos de estudo permitiu, igualmente, colocar hipóteses sobre o território de vivência, de circulação e de exploração de cada comunidade.Fundação para a Ciência e Tecnologi

Modelo de aprovechamiento de aguas lluvias en zonas de pobreza extrema

Las ventajas de captar agua lluvia en un entorno natural son: agua extremadamente limpia en comparación con otras fuentes de agua dulce disponibles, recurso esencialmente gratuito e independiente de empresas suministradoras habituales y que requiere de infraestructura sencilla para su captación, almacenamiento y distribución. El sistema de captación del agua lluvia permite almacenarla y posteriormente someter a tratamiento la que se utilizará para el consumo humano. A este sistema se le denomina CATDALL, que fue el prototipo resultado final del desarrollo del proyecto, gracias al apoyo del Fondo para la Investigación en Educación Superior (FIES) y la Universidad Tecnológica de El Salvador (UTEC). El prototipo puede ser replicable en otros centros escolares, que presenten escasez de agua bajo las circunstancias que fueren o como simple alternativa de ahorro aprovechando un recurso natural que es gratuito.Investigación desarrollada bajo el convenio FIES-UTEC, 2008-2009Universidad Tecnológica de El Salvado

A Molecular Phylogeny And New Infrageneric Classification Of Mucuna Adans. (leguminosae-papilionoideae) Including Insights From Morphology And Hypotheses About Biogeography

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Premise of research. The genus Mucuna has a pantropical distribution and comprises approximately 105 species, many of which show great economic value for forage, ornament, and medicine. To date, phylogenetic relationships within Mucuna have not been investigated using molecular data. The aim of this study was to build a phylogenetic framework for Mucuna to address questions about its monophyly, infrageneric relationships, divergence times, and biogeography. Methodology. We sequenced plastid (trnL-F) and nuclear ribosomal (internal transcribed spacer) regions and applied Bayesian and maximum likelihood analyses. An ancestral area reconstruction coupled with a divergence time analysis was used to investigate the historical biogeography of the genus. Pivotal results. Our results show that Mucuna is a monophyletic genus and that subgenus Stizolobium is a monophyletic group within it. We present here the analyses and results that support the need to recircumscribe subgenus Mucuna and to segregate a small group of species with large fruits into a newly proposed subgenus (to be described formally elsewhere after additional investigations). Conclusions. On the basis of ancestral area reconstruction and divergence time analyses, we conclude that the genus Mucuna originated and first diversified in the Paleotropics around 29.2 Ma and achieved a pantropical distribution through multiple long-distance dispersal events, which were facilitated by the occurrence of seeds adapted to oceanic dispersal.17717689Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Science without Borders Program [245590/2012-9]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Shirley A. Graham Fellowship, Missouri Botanical GardenBiologia Vegetal postgraduate program at Universidade Estadual de Campinas (UNICAMP), BrazilRoyal Botanic Gardens, KewMissouri Botanical GardenCentro de Biologia Molecular e Engenharia Genetica (CBMEG) Laboratory, BrazilEnvironment Research and Technology Development Fund of the Ministry of the Environment, Japan [S-9]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

The quorum sensing com system regulates pneumococcal colonisation and invasive disease in a pseudo-stratified airway tissue model.

BACKGROUND The effects of the com quorum sensing system during colonisation and invasion of Streptococcus pneumoniae (Spn) are poorly understood. METHODS We developed an ex vivo model of differentiated human airway epithelial (HAE) cells with beating ciliae, mucus production and tight junctions to study Spn colonisation and translocation. HAE cells were inoculated with Spn wild-type TIGR4 (wtSpn) or its isogenic ΔcomC quorum sensing-deficient mutant. RESULTS Colonisation density of ΔcomC mutant was lower after 6 h but higher at 19 h and 30 h compared to wtSpn. Translocation correlated inversely with colonisation density. Transepithelial electric resistance (TEER) decreased after pneumococcal inoculation and correlated with increased translocation. Confocal imaging illustrated prominent microcolony formation with wtSpn but disintegration of microcolony structures with ΔcomC mutant. ΔcomC mutant showed greater cytotoxicity than wtSpn, suggesting that cytotoxicity was likely not the mechanism leading to translocation. There was greater density- and time-dependent increase of inflammatory cytokines including NLRP3 inflammasome-related IL-18 after infection with ΔcomC compared with wtSpn. ComC inactivation was associated with increased pneumolysin expression. CONCLUSIONS ComC system allows a higher organisational level of population structure resulting in microcolony formation, increased early colonisation and subsequent translocation. We propose that ComC inactivation unleashes a very different and possibly more virulent phenotype that merits further investigation