Aproximación a los parques de Barranquilla como puntos de encuentro comunicativo: Primeras reflexiones

El presente artículo corresponde a las primeras reflexiones que exploran los cambios en el imaginario colectivo y la cultura ciudadana de los parques en Barranquilla, Colombia. Hasta hace 6 años, Barranquilla presentaba una serie de problemas estructurales en sus espacios públicos que produjeron una significación en la que los parques, específicamente, eran sinónimo de inseguridad y apatía entre sus habitantes. Sin embargo, actualmente, y tras un proceso de renovación urbana estos sitios de interacción y comunicación han experimentado una transformación que se manifiesta en una participación considerablemente distinta a la de décadas anteriores. Partiendo de un enfoque cualitativo se analizó cómo los barranquilleros perciben esta situación; ¿cómo se expresan los cambios recientes?, para, así, realizar un prudente acercamiento a reflexiones críticas sobre el panorama de la significación de lo público en Barranquilla, en términos comunicativos y culturales. Con base en este proceso se encontró que, si bien las percepciones han cambiado manifestándose en prácticas sociales específicas dentro de estos lugares, todavía hay preferencias por parte de los ciudadanos por usar espacios de acceso libre, pero de carácter privado, para realizar sus diversas interacciones sociales y establecer vínculos comunicacionales. Se concluyó que es necesario aproximarse de forma reflexiva y crítica a esta situación, a una escala mayor, para comprender el estado actual de la relación de los barranquilleros con sus parques, así como con los espacios públicos en la ciudad

Avaliação toxicológica de lixiviados de aterro sanitário tratados usando o crustáceo de água doce Daphnia magna.

Os resíduos sólidos urbanos, gerados em grande escala pela sociedade moderna, precisam de ser corretamente descartados por forma a mitigar o seu impacto ambiental e na saúde pública. Estes resíduos são normalmente depositados em aterros sanitários, e, consequentemente, são gerados lixiviados altamente tóxicos que precisam de ser tratados. Este trabalho tem como objetivo avaliar a eficácia de diferentes tratamentos eletroquímicos na redução da toxicidade de um concentrado de lixiviado de aterro sanitário. O concentrado de lixiviado, resultante da aplicação de um processo de osmose inversa, foi tratado por processos eletroquímicos combinados, eletrocoagulação (EC) seguida de eletro-Fenton (EF) com diferentes intensidades de corrente e com diferentes concentrações iniciais de ferro. A eficácia do tratamento na diminuição da toxicidade foi avaliada através de ensaios de toxicidade aguda com o organismo modelo Daphnia magna. Os resultados obtidos mostraram que os ensaios de EF realizados à densidade de corrente mais alta (200 A m-2) e com uma concentração de Fe inferior (60 mg L-1) permitiram uma diminuição da toxicidade inicial de 61,305 unidades tóxicas (UTs) para 33,195 UTs, correspondente a uma redução da toxicidade de cerca de 46

Human depression: a new approach in quantitative psychiatry

The biomolecular approach to major depression disorder is explained by the different steps that involve cell membrane viscosity, Gsα protein and tubulin. For the first time it is hypothesised that a biomolecular pathway exists, moving from cell membrane viscosity through Gsα protein and Tubulin, which can condition the conscious state and is measurable by electroencephalogram study of the brain's γ wave synchrony

Directed acyclic graph kernels for structural RNA analysis

<p>Abstract</p> <p>Background</p> <p>Recent discoveries of a large variety of important roles for non-coding RNAs (ncRNAs) have been reported by numerous researchers. In order to analyze ncRNAs by kernel methods including support vector machines, we propose stem kernels as an extension of string kernels for measuring the similarities between two RNA sequences from the viewpoint of secondary structures. However, applying stem kernels directly to large data sets of ncRNAs is impractical due to their computational complexity.</p> <p>Results</p> <p>We have developed a new technique based on directed acyclic graphs (DAGs) derived from base-pairing probability matrices of RNA sequences that significantly increases the computation speed of stem kernels. Furthermore, we propose profile-profile stem kernels for multiple alignments of RNA sequences which utilize base-pairing probability matrices for multiple alignments instead of those for individual sequences. Our kernels outperformed the existing methods with respect to the detection of known ncRNAs and kernel hierarchical clustering.</p> <p>Conclusion</p> <p>Stem kernels can be utilized as a reliable similarity measure of structural RNAs, and can be used in various kernel-based applications.</p

Duality Invariant Actions and Generalised Geometry

We construct the non-linear realisation of the semi-direct product of E(11) and its first fundamental representation at lowest order and appropriate to spacetime dimensions four to seven. This leads to a non-linear realisation of the duality groups and introduces fields that depend on a generalised space which possess a generalised vielbein. We focus on the part of the generalised space on which the duality groups alone act and construct an invariant action.Comment: 59 pages (typos fixed and added comments

Bio-nanotechnology application in wastewater treatment

The nanoparticles have received high interest in the field of medicine and water purification, however, the nanomaterials produced by chemical and physical methods are considered hazardous, expensive, and leave behind harmful substances to the environment. This chapter aimed to focus on green-synthesized nanoparticles and their medical applications. Moreover, the chapter highlighted the applicability of the metallic nanoparticles (MNPs) in the inactivation of microbial cells due to their high surface and small particle size. Modifying nanomaterials produced by green-methods is safe, inexpensive, and easy. Therefore, the control and modification of nanoparticles and their properties were also discussed

Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund

Sustained CD28 Expression Delays Multiple Features of Replicative Senescence in Human CD8 T Lymphocytes

CD28 costimulatory signal transduction in T lymphocytes is essential for optimal telomerase activity, stabilization of cytokine mRNAs, and glucose metabolism. During aging and chronic infection with HIV-1, there are increased proportions of CD8 T lymphocytes that lack CD28 expression and show additional features of replicative senescence. Moreover, the abundance of these cells correlates with decreased vaccine responsiveness, early mortality in the very old, and accelerated HIV disease progression. Here, we show that sustained expression of CD28, via gene transduction, retards the process of replicative senescence, as evidenced by enhanced telomerase activity, increased overall proliferative potential, and reduced secretion of pro-inflammatory cytokines. Nevertheless, the transduced cultures eventually do reach senescence, which is associated with increased CTLA-4 gene expression and a loss of CD28 cell surface expression. These findings further elucidate the central role of CD28 in the replicative senescence program, and may ultimately lead to novel therapies for diseases associated with replicative senescence

Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund