Recuperación de sulfato de aluminio a partir de lodos generados en plantas de potabilización de agua

Se estudió la recuperación mediante ácido sulfúrico, de sulfato de aluminio a partir de lodos recolectados durante las diferentes rutinas de operación y mantenimiento de los sedimentadores en plantas de potabilización. Se efectuaron ensayos de jarras a pHs 1,5, 2,5 y 3,5 y tiempos de mezcla lenta de 5, 30 y 100 minutos. Se alcanzaron porcentajes de recuperación de aluminio entre 18 y 64% y soluciones con concentraciones entre 8,9 y 1510 mg Al/l. Finalmente, se evaluó la factibilidad económica de la reutilización en el proceso de potabilización, de la solución de coagulante recuperado

PROCESO DE INFORMACIÓN EN EL FORTALECIMIENTO DE LA GESTIÓN COMUNITARIA PARA EL SANEAMIENTO BÁSICO. CENTRO POBLADO LA FLORIDA, MUNICIPIO DE PEREIRA

En la cuenca media del río Otún, municipio de Pereira, Colombia, se dio inicio al fortalecimiento de la gestión comunitaria para la apropiación del servicio de alcantarillado, como aspecto clave de la sostenibilidad de las soluciones implementadas en la localidad de La Florid

Valuation of the research and education ecosystem services as input for making decisions from the perspective of risk management and climate change

El artículo presenta la valoración de los servicios ecosistémicos de investigación y educación en la microcuenca de la quebrada Dalí, ubicada dentro de la hacienda Lisbrán; a través de tres objetivos específicos: primero, identificación de información biofísica y socioeconómica del área de estudio (línea base); segundo valoración integral del servicio de “investigación y educación” ofrecido por la microcuenca; por último analizar cómo los servicios ecosistémicos y la educación ambiental pueden convertirse en un insumo para la gestión local. Para el primer se identificaron y clasificaron algunos servicios ecosistémicos mediante información secundaria. Estos fueron evaluados mediante los métodos de ranking y rating, obteniendo los mayores puntajes los servicios de oferta y regulación hídrica, y como segundo y en el cual se fundamenta el artículo los servicios educación y de investigación. Para el segundo se realizó una valoración integral del servicio de “investigación-educación” en sus aspectos ecológicos, sociales y económicos, tomando como objeto de estudio siete programas (pregrado y posgrado) de la Universidad Tecnológica de Pereira. El tercer se desarrolló con la participación de los scout “rama de lobatos” como parte del diseño de un proyecto de educación ambiental que ellos y otras partes interesadas fomenta la importancia de los recursos naturales y los beneficios de la sub-cuenca Dalí como proveedor de servicios ecosistémicos. Los resultados muestran que el área de estudio tiene un gran potencial para ser usada como estación de investigación y sitio de prácticas para estudiantes de pregrado y posgrado. A pesar del hecho de que los profesores y estudiantes entrevistados reconocen la importancia de los atributos ecológicos que ofrece la subcuenca de la quebrada Dali, ninguno de ellos expreso disponibilidad a pagar por usar este sitio como lugar para desarrollar sus investigaciones o tesis de investigación. Sin embargo, la experiencia del trabajo con niños de los grupos scouts en el sitio de estudio sugiere que el sitio tiene un gran potencial no solo para hacer investigación sino también para para la educación ambiental.The article presents the valuation of the research and education ecosystem services in the Dali mountain stream, located in the Lisbran farm through three specific objectives: first, to identify the biophysical and socioeconomic information of the area of study (Baseline); second, to assess comprehensively the "research and education" service offered by the micro basin; and third, to analyze how the ecosystem services and environmental education can become input for local management. Some ecosystem services were identified and classified through secondary information to accomplish the first objective. These were evaluated using the ranking and rating methods, obtaining the highest scores on services of water supply and, in second place, research and education services in which this article is based. A comprehensive assessment of “the research and education” service considering its ecological, social and economic aspects was carried out to achieve the second objective. Seven undergraduate and graduate programs from Universidad Tecnológica de Pereira were taken as the object of study. The third objective was developed with the participation of the cub scouts group as part of the design of an environmental education project that, as well as other stakeholders, encourage the importance of natural resources and the benefits of the Dalí mountain stream as a supplier of valuable ecosystem services. The results show that the area of study has a great potential to be used as a research and educational station as well as internship site for undergraduate and graduate students. Despite the fact that the professors and students interviewed recognize the importance of the ecological attributes offered by the Dali mountain stream, none of them expressed the willingness to pay for the use of this site as a location to conduct their research and thesis projects. However, the experience of working with children from the scout groups suggests that the site has a great potential not only for research but also for environmental education activities

Validación de un nuevo método de dosificación de metadona en pacientes del Programa de Mantenimiento con Metadona

Validació

Asymptotics and zeros of Sobolev orthogonal polynomials on unbounded supports

In this paper we present a survey about analytic properties of polynomials orthogonal with respect to a weighted Sobolev inner product such that the vector of measures has an unbounded support. In particular, we are focused in the study of the asymptotic behaviour of such polynomials as well as in the distribution of their zeros. Some open problems as well as some new directions for a future research are formulated.Comment: Changed content; 34 pages, 41 reference

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features

Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n 5 11) and pituitary adenomas (n 5 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas comparedwith normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24–72 h) increasedGHandACTHsecretion, Ca21 and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors

Splicing Machinery is Dysregulated in Pituitary Neuroendocrine Tumors and is Associated with Aggressiveness Features

Pituitary neuroendocrine tumors (PitNETs) constitute approximately 15% of all brain tumors, and most have a sporadic origin. Recent studies suggest that altered alternative splicing and, consequently, appearance of aberrant splicing variants, is a common feature of most tumor pathologies. Moreover, spliceosome is considered an attractive therapeutic target in tumor pathologies, and the inhibition of SF3B1 (e.g., using pladienolide-B) has been shown to exert antitumor effects. Therefore, we aimed to analyze the expression levels of selected splicing-machinery components in 261 PitNETs (somatotropinomas/non-functioning PitNETS/corticotropinomas/prolactinomas) and evaluated the direct effects of pladienolide-B in cell proliferation/viability/hormone secretion in human PitNETs cell cultures and pituitary cell lines (AtT-20/GH3). Results revealed a severe dysregulation of splicing-machinery components in all the PitNET subtypes compared to normal pituitaries and a unique fingerprint of splicing-machinery components that accurately discriminate between normal and tumor tissue in each PitNET subtype. Moreover, expression of specific components was associated with key clinical parameters. Interestingly, certain components were commonly dysregulated throughout all PitNET subtypes. Finally, pladienolide-B reduced cell proliferation/viability/hormone secretion in PitNET cell cultures and cell lines. Altogether, our data demonstrate a drastic dysregulation of the splicing-machinery in PitNETs that might be associated to their tumorigenesis, paving the way to explore the use of specific splicing-machinery components as novel diagnostic/prognostic and therapeutic targets in PitNETs