Implementación de red inalámbrica comunitaria para Ciudad Bolívar

Este documento expone el proceso llevado a cabo para la realización de la red inalámbrica comunitaria de la localidad Ciudad Bolívar (Bolivarwireless),que es una de las zonas con mayores índices de pobreza en Bogotá-Colombia. Aquí se expone la manera en que la investigación condujo al diseño e implementación de los nodos de la red inalámbrica comunitaria, basados en topología mesh y varias aplicaciones de tecnologías de la información y las comunicaciones (TIC) que son actualmente usadas por la comunidad, beneficiada con la cobertura de los nodos de la red inalámbrica en la localidad. Luego, se evalúan los nodos implementados y finalmente se presenta las conclusiones y recomendaciones

Systematic Tools for the Conceptual Design of Inherently Safer Chemical Processes

Society is continuously facing challenges for safer chemical plants design, which is usually driven by economic criteria during the early steps of the design process, relegating safety concerns to the latest stages. This paper highlights the synergy of merging Process System Engineering tools with inherent safety principles. First, we design a superstructure that comprises several alternatives for streams, equipment, and process conditions, which exhibit different performance of economic and inherently safer indicators, the total annualized cost, and the Dow’s Fire and Explosion Index, respectively. The solution to this multiobjective problem is given by a Pareto set of solutions that indicates the existing trade-off between both objectives. The capabilities of the proposed framework are illustrated through two case studies, which solutions provide valuable insights into the design problem and are intended to guide decision-makers toward the adoption of inherently safer process alternatives.The authors acknowledge financial support from “Proyectos de l+D para grupos de investigación emergentes GV/2016/005” (Conselleria d’Educació, Investigació, Cultura i Esport, GENERALITAT VALENCIANA) and from the Spanish “Ministerio de Economía, Industria y Competitividad” (CTQ2016-77968-C3-02-P, AEI/FEDER, UE)

Direct construction of the effective action of chiral gauge fermions in the anomalous sector

The anomaly implies an obstruction to a fully chiral covariant calculation of the effective action in the abnormal parity sector of chiral theories. The standard approach then is to reconstruct the anomalous effective action from its covariant current. In this work we use a recently introduced formulation which allows to directly construct the non trivial chiral invariant part of the effective action within a fully covariant formalism. To this end we develop an appropriate version of Chan's approach to carry out the calculation within the derivative expansion. The result to four derivatives, i.e., to leading order in two and four dimensions and next-to-leading order in two dimensions, is explicitly worked out. Fairly compact expressions are found for these terms.Comment: 19 pages, revtex, no figures. Writing improved. (Refers to arXiv:0807.1696.

ZnO-mesoporous glass scaffolds loaded with osteostatin and mesenchymal cells improve bone healing in a rabbit bone defect

The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2–10.3CaO–3.3P2O5–4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN + MSC, 4ZN + OST or 4ZN + MSC + OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological, and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice

Modelo predictivo del índice de anisotropía del semicoque a partir de las propiedades de los carbones de la Cordillera Oriental de Colombia

This study developed a theoretical model for the determination of the Coke Anisotropy Quotient (CAQ) of semi-coke from the properties of its precursor coal. This is an useful parameter to define the resistance and reactivity of semi-coke in the blast furnace. For 36 semi-coke samples, a textural analysis was performed alongside a fluidity test to determine the real CAQ. The main textures observed were: isotropic and circular for high volatile bituminous coals (HVB); lenticular and fine ribbons for the medium volatile bituminous coals (MVB); and medium and thick ribbons for the low volatile bituminous coals (LVB). The CAQ varied in a range from 1 to 11. A principal component analysis (PCA) and multiple regression allowed to discriminated the importance of certain coal properties, in determining the CAQ to be recognized and to estimate parameters of the mathematical model. The statistical analysis suggested that CAQ can be best predicted from the fluidity, volatile matter, and Ro of the parent coals. The veracity of this model result was then tested using a second dataset from Poland. This work optimizes the usefulness of standard datasets in the prediction of CAQ's offering a means of quality control that could be implemented in Colombian coke production.En esta investigación se desarrolló un modelo teórico para la determinación del Cociente de Anisotropía del Coque (CAQ) del semicoque a partir de las propiedades de su carbón precursor. El CAQ permite definir la resistencia y la reactividad del semicoque en el alto horno. Usando material residual de las pruebas de fluidez se realizó un análisis textural para determinar el CAQ real sobre 36 muestras de semicoque. Las principales texturas observadas para los carbones bituminosos fueron: isotrópicas y circulares para los de alta volatilidad (HVB); cintas lenticulares y finas para los de media volatilidad (MVB); y cintas medias y gruesas para los de baja volatilidad (LVB). El CAQ varió en un rango de 1 a 11. Análisis de componentes principales (PCA) y regresión múltiple permitieron reconocer la importancia de ciertas propiedades del carbón para determinar el CAQ. El análisis estadístico sugirió que el CAQ puede predecirse mejor a partir de la fluidez,la materia volátil y el Ro de los carbones precursores. Este modelo fue validado a través de la comparación con datos reales de carbones de Polonia. Este trabajo proporciona un medio de control de calidad que podríaimplementarse en la producción de coque colombiano.&nbsp

Contenido de minerales en grano, harina y salvado de variedades de quinua.

Se comparan el contenido proteínico de la quinua con la cebada, maíz amarillo, maíz blanco y trigo. Para el efecto se determinan los elementos minerales: P, Ca, K, Mg, Na, Fe, Cu, Mn y Zn para 15 variedades de quinua cultivadas en los países andinos. La determinación se hizo en los 3 estratos: grano, harina y salvado. Los porcentajes de P en el grano, fluctuaron entre 0.62 a 0.33 por ciento con promedio de 0.47 por ciento para las 15 variedades. El Ca varió en el grano entre 0.39 a 0.14 por ciento con promedio 0.19 por ciento, siendo estos contenidos superiores a los reportados para los otros granos. Los contenidos promedios de K y Mg para el grano, fueron 0.87 y 0.26 oscilando entre 1.98 a 0.50 por ciento para el K y 0.46 a 0.13 para el Mg, siendo suficientes, en una dieta balanceada para humanos y llenando los requerimientos para ganado bovino. En cuanto a Na, Fe, Cu, Mn y Zn, a excepción del Na los valores se encuentran por encima de los reportados para cebada, maíz y trigo. En cuanto a los 3 estratos, los mayores niveles de minerales en todas las variedades lo presentó el salvado con relación a las cantidades encontradas para grano y harina. Comparando el contenido de minerales y saponina de estas mismas variedades, se observó una relación inversaQuinua-Amaranthus caudatu

ZnO-mesoporous glass scaffolds loaded with osteostatin and mesenchymal cells improve bone healing in a rabbit bone defect.

The use of 3D scaffolds based on mesoporous bioactive glasses (MBG) enhanced with therapeutic ions, biomolecules and cells is emerging as a strategy to improve bone healing. In this paper, the osteogenic capability of ZnO-enriched MBG scaffolds loaded or not with osteostatin (OST) and human mesenchymal stem cells (MSC) was evaluated after implantation in New Zealand rabbits. Cylindrical meso-macroporous scaffolds with composition (mol %) 82.2SiO2–10.3CaO–3.3P2O5–4.2ZnO (4ZN) were obtained by rapid prototyping and then, coated with gelatin for easy handling and potentiating the release of inorganic ions and OST. Bone defects (7.5 mm diameter, 12 mm depth) were drilled in the distal femoral epiphysis and filled with 4ZN, 4ZN+MSC, 4ZN+OST or 4ZN+MSC+OST materials to evaluate and compare their osteogenic features. Rabbits were sacrificed at 3 months extracting the distal third of bone specimens for necropsy, histological and microtomography (µCT) evaluations. Systems investigated exhibited bone regeneration capability. Thus, trabecular bone volume density (BV/TV) values obtained from µCT showed that the good bone healing capability of 4ZN was significantly improved by the scaffolds coated with OST and MSC. Our findings in vivo suggest the interest of these MBG complete systems to improve bone repair in the clinical practice

Characterization and engineering of the biosynthesis gene cluster for antitumor macrolides PM100117 and PM100118 from a marine actinobacteria: generation of a novel improved derivative

Additional file 1: Figure S1. Sequence alignment of the cluster PKS domains active sites. LD, loading domain; M1-M20, extension modules. Polyketide synthase domains are as follows: KS, ketosynthase; AT, acyltransferase; KR, ketoreductase; DH, dehydratase; ER, enoilreductase; ACP, acyl carrier protein; CAL, CoA-ligase. Figure S2. Genetic complementation of mutant strains. UPLC analysis of PM100117 (1) and PM100118 (2) production in strains GUA-pS, CPgonP8, CPgonM4, CPgonMT, CPgonSL, CPgonS1, CPgonS2, CPgonCP, CPgonMR and CPgonL1. Figure S3. Antibiotic activity test of compound 5. Diffusion disc assay against Saccharomyces cerevisiae and Micrococcus luteus. The length (cm) of the inhibition-growth halo is indicated by numbers and yellow lines. Methods S2. Antibiotic activity assay. Format: PDF

Wind power field reconstruction from a reduced set of representative measuring points

In this paper we deal with a problem of representative measuring points selection for long-term wind power analysis. It has direct applications such as wind farm prospective location or long-term power generation prediction in wind-based energy facilities. The problem’s objective is to select the best set of N measuring points (i.e. N representative points), in such a way that a wind power error reconstruction measure is minimized, considering a monthly average wind power field. In order to solve this problem, we use a novel meta-heuristic algorithm, the Coral Reefs Optimization with Substrate Layer, which is an evolutionary-type method able to combine different search procedures within a single population. The CRO-SL is hybridized with the Analogue Method as wind power reconstruction method, to identify the most representative points for the wind field. The proposed approach has been tested in the reconstruction of monthly average wind power fields in Europe, from reanalysis data (ERAInterim reanalysis). The method exhibits strong performance as evidenced from the experiments carried out. The solutions obtained show that the more significant measuring points are mainly located over the Atlantic ocean, which is consistent with the wind speed climatology of the Northern hemisphere midlatitudes. We have also analyzed the set of least representative points to reconstruct the wind power field (less informative points for whole reconstruction of the field), obtaining points mainly located at the North of Scandinavia (which may be associated with the circumpolar circulation), and some points in the Eastern Mediterranean, which seem to be related to the Etesian winds. Reconstructions at seasonal scales show similar results, which provides confidence on the robustness of the proposed method. The proposed methodology can be further applied to alternative energy-related problems, such as the selection of critical energy infra-structures or the selection of critical points for climate change studies, among others

Parathyroid hormone-related protein (107-111) improves the bone regeneration potential of gelatin-glutaraldehyde biopolymer-coated hydroxyapatite

Biopolymer-coated nanocrystalline hydroxyapatite (HA) made as macroporous foams which are degradable and flexible are promising candidates as orthopaedic implants. The C-terminal (107-111) epitope of parathyroid hormone-related protein (PTHrP) exhibits osteogenic properties. The main aim of this study was to evaluate whether PTHrP (107-111) loading into gelatin-glutaraldehyde biopolymer-coated HA (HA(GIu)) scaffolds would produce an optimal biomaterial for tissue engineering applications. HA(GIu) scaffolds with and without PTHrP (107-111) were implanted into a cavitary defect performed in both distal tibial metaphysis of adult rats. Animals were sacrificed after 4 weeks for histological, microcomputerized tomography and gene expression analysis of the callus. At this time, bone healing occurred only in the presence of PTHrP (107-111)-containing HA(Giu) implant, related to an increase in bone volume/tissue volume and trabecular thickness, cortical thickness and gene expression of osteocalcin and vascular cell adhesion molecule I, but a decreased gene expression of Wnt inhibitors, SOST and dickkopf homolog 1. The autonomous osteogenic effect of the PTHrP (107-111)-loaded HA(Giu) scaffolds was confirmed in mouse and human osteoblastic cell cultures. Our findings demonstrate the advantage of loading PTHrP (107-111) into degradable HA(GIu) scaffolds for achieving an optimal biomaterial that is promising for low load bearing clinical applications. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved