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1.
Phys Rev E ; 101(5-1): 052117, 2020 May.
Article de Anglais | MEDLINE | ID: mdl-32575311

RÉSUMÉ

The transfer entropy and the transfer entropy rate are closely related concepts that measure information exchange between two dynamical systems. These measures allow us to study linear and nonlinear causality relations and can be estimated through the use of different methodologies. However, some of them assume a data model and/or are computationally expensive. This article depicts a methodology to estimate the transfer entropy rate between two systems through the Lempel-Ziv complexity. This methodology offers a set of advantages: It estimates the transfer entropy rate from two single discrete series of measures, it is not computationally expensive, and it does not assume any data model. The simulation results over three different unidirectional coupled dynamical systems suggest that this methodology can be used to assess the direction and strength of the information flow between systems. Moreover, it provides good estimations for short-length time series.

2.
rev. udca actual. divulg. cient ; 21(2): 377-384, jul.-dic. 2018. tab, graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1094740

RÉSUMÉ

RESUMEN El cultivo comercial de hortensias para flor de exportación ocupa un renglón importante en el sector económico del oriente antioqueño, por ser fuente de empleo y de desarrollo en la zona. La hortensia (Hydrangea macrophylla) es afectada por numerosos organismos fitopatógenos, entre ellos, nematodos del género Aphelenchoides, los que ocasionan, en el follaje, lesiones necróticas angulares, malformación de flor, enanismo y un daño indirecto en la tasa fotosintética, demeritando los parámetros de calidad para exportación. El objetivo de este estudio fue identificar, molecularmente, las especies del nematodo Aphelenchoides asociadas al cultivo de hortensias de color, en los municipios de Medellín (Santa Elena), La Ceja y Rionegro, siendo este el primer reporte para Colombia, de las especies de este género. Para la ejecución del estudio, se realizaron 10 muestreos en cultivos comerciales, distribuidos entre los tres municipios mencionados. Los nematodos extraídos, se sometieron a pruebas basadas en el análisis de ADN, haciendo uso del marcador ribosomal 18S. Los análisis filogenéticos practicados mostraron la presencia de la especie Aphelenchoides ritzemabosi en cultivos de hortensias, del corregimiento de Santa Elena y, de A. fragarie, en los municipios de La Ceja y Rionegro.


ABSTRACT Hydrangea macrophylla commercial crops have an important economic significance for the eastern region of the department of Antioquia, Colombia, due to its impact on employment and local development. This flowering plant can be attacked by several phytopathogens among them nematodes of the genus Aphelenchoides; which can produce necrotic lesions on the plant leaves as well decreased photosynthetic rate, dwarfism, and flower malformation. Additionally, this pathogen is considered a regulated pest and limits the international commercialization of the flower. The aim of this study was to molecularly identify the Aphelenchoides species associated with infected H. macrophylla plants in crops the municipalities of Medellín, La Ceja, and Rionegro. This is the first report of the species of this phytopathogen for Colombia. The sampling activities were performed in ten commercial crops locate at the three municipalities. The isolated nematodes were subject to DNA-based tests were the 18S rDNA gene was amplified, sequenced and analyzed using phylogenetic methods. The obtained results showed the infection of Aphelenchoides ritzemabosi within the Santa Elena (Medellin) area in crops and A. fragarie within the municipalities of La Ceja, and Rionegro.

3.
Rev. salud pública ; Rev. salud pública;19(6): 806-813, nov.-dic. 2017. tab, graf
Article de Espagnol | LILACS | ID: biblio-962075

RÉSUMÉ

RESUMEN Objetivo Caracterizar la microbiota bacteriana presente en los biosólidos generados en una de las plantas de tratamiento de aguas residuales más grande de Colombia. Materiales y Métodos Se utilizó la plataforma de secuenciamiento 454 de la compañía Roche para secuenciar las regiones variables V1-V3 y V6-V9 del marcador molecular 16S rRNA y caracterizar la microbiota. Adicionalmente, se aplicaron estrategias filogenéticas para la identificación de especies bacterianas de importancia. Resultados Nuestros análisis muestran que los Phyla más abundantes son Chloro-flexi, Proteobacteria, Bacteroidetes, Actinobacteria y Firmicutes. Los géneros clasificados más abundantes fueron Pseudomonas, Dysgonomonas y Proteiniphilum. Sin embargo, el grupo dominante según la región variable V1-V3 es una Anaerolineaceae que no se ajusta a las especies descritas para esta familia. Conclusiones En las muestras de biosólido analizadas predominan bacterias ambientales que participan en los procesos de estabilización de la materia orgánica durante los tratamientos biológicos de tipo secundario y la digestión anaerobia. Se detectaron secuencias de especies dentro de la familia Anaerolineaceae, los análisis filogenéticos muestran que probablemente se trata de especies no descritas. En el momento del estudio, se encontró que en el sistema de digestión anaerobia se genera biosolido con una baja carga de bacterias potencialmente patógenas.(AU)


ABSTRACT Objective To describe bacterial microbiota in the biosolids generated in one of the largest wastewater treatment plants of Colombia. Materials and Methods Using NGS technology, 16S rRNA Gene Amplicon libraries were amplified and sequenced. The Roche 454 FLX Titanium platform was used, while the V1-V3 and V6-V9 hypervariable regions were amplified and analyzed independently. Amplicon processing and bacterial classification were performed using the AmpliconNoise pipeline and the RDP Classifier tool. Results The analysis showed that the most dominant Phyla in the biosolids were Chlo-roflexi, Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. The most dominant genera were Pseudomonas, Dysgonomonas and Proteiniphilum; however, the dominant group according in the V1-V3 variable region was Anaerolineaceae, which does not conform to the species described for this family. Pathogenic bacteria such as Salmonella and E. coli/Shigella were not detected in the studied biosolid sample. Conclusions In the biosolids samples analyzed, environmental bacteria involved in organic matter stabilization processes during secondary biological treatments and anaerobic digestion were predominant. One of the dominant species in this sludge is a novel species of the Anaerolineaceae group. At the time of the study, it was found that the anaerobic digester system was able to maintain pathogenic bacteria at very low concentrations.(AU)


Sujet(s)
Eaux d'égout/analyse , ARN ribosomique 16S , Purification de l'eau/normes , Microbiote , Colombie , Techniques de diagnostic moléculaire
4.
Rev Salud Publica (Bogota) ; 19(6): 806-813, 2017.
Article de Espagnol | MEDLINE | ID: mdl-30183835

RÉSUMÉ

OBJECTIVE: To describe bacterial microbiota in the biosolids generated in one of the largest wastewater treatment plants of Colombia. MATERIALS AND METHODS: Using NGS technology, 16S rRNA Gene Amplicon libraries were amplified and sequenced. The Roche 454 FLX Titanium platform was used, while the V1-V3 and V6-V9 hypervariable regions were amplified and analyzed independently. Amplicon processing and bacterial classification were performed using the AmpliconNoise pipeline and the RDP Classifier tool. RESULTS: The analysis showed that the most dominant Phyla in the biosolids were Chlo-roflexi, Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. The most dominant genera were Pseudomonas, Dysgonomonas and Proteiniphilum; however, the dominant group according in the V1-V3 variable region was Anaerolineaceae, which does not conform to the species described for this family. Pathogenic bacteria such as Salmonella and E. coli/Shigella were not detected in the studied biosolid sample. CONCLUSIONS: In the biosolids samples analyzed, environmental bacteria involved in organic matter stabilization processes during secondary biological treatments and anaerobic digestion were predominant. One of the dominant species in this sludge is a novel species of the Anaerolineaceae group. At the time of the study, it was found that the anaerobic digester system was able to maintain pathogenic bacteria at very low concentrations.


OBJETIVO: Caracterizar la microbiota bacteriana presente en los biosólidos generados en una de las plantas de tratamiento de aguas residuales más grande de Colombia. MATERIALES Y MÉTODOS: Se utilizó la plataforma de secuenciamiento 454 de la compañía Roche para secuenciar las regiones variables V1-V3 y V6-V9 del marcador molecular 16S rRNA y caracterizar la microbiota. Adicionalmente, se aplicaron estrategias filogenéticas para la identificación de especies bacterianas de importancia. RESULTADOS: Nuestros análisis muestran que los Phyla más abundantes son Chloro-flexi, Proteobacteria, Bacteroidetes, Actinobacteria y Firmicutes. Los géneros clasificados más abundantes fueron Pseudomonas, Dysgonomonas y Proteiniphilum. Sin embargo, el grupo dominante según la región variable V1-V3 es una Anaerolineaceae que no se ajusta a las especies descritas para esta familia. CONCLUSIONES: En las muestras de biosólido analizadas predominan bacterias ambientales que participan en los procesos de estabilización de la materia orgánica durante los tratamientos biológicos de tipo secundario y la digestión anaerobia. Se detectaron secuencias de especies dentro de la familia Anaerolineaceae, los análisis filogenéticos muestran que probablemente se trata de especies no descritas. En el momento del estudio, se encontró que en el sistema de digestión anaerobia se genera biosolido con una baja carga de bacterias potencialmente patógenas.


Sujet(s)
Bactéries/isolement et purification , Microbiote , Eaux d'égout/microbiologie , Colombie
5.
Phys Rev E ; 94(1-1): 012212, 2016 Jul.
Article de Anglais | MEDLINE | ID: mdl-27575128

RÉSUMÉ

In this article, the noise-assisted correlation integral (NCI) is proposed. The purpose of the NCI is to estimate the invariants of a dynamical system, namely the correlation dimension (D), the correlation entropy (K_{2}), and the noise level (σ). This correlation integral is induced by using random noise in a modified version of the correlation algorithm, i.e., the noise-assisted correlation algorithm. We demonstrate how the correlation integral by Grassberger et al. and the Gaussian kernel correlation integral (GCI) by Diks can be thought of as special cases of the NCI. A third particular case is the U-correlation integral proposed herein, from which we derived coarse-grained estimators of the correlation dimension (D_{m}^{U}), the correlation entropy (K_{m}^{U}), and the noise level (σ_{m}^{U}). Using time series from the Henon map and the Mackey-Glass system, we analyze the behavior of these estimators under different noise conditions and data lengths. The results show that the estimators D_{m}^{U} and σ_{m}^{U} behave in a similar manner to those based on the GCI. However, for the calculation of K_{2}, the estimator K_{m}^{U} outperforms its GCI-based counterpart. On the basis of the behavior of these estimators, we have proposed an automatic algorithm to find D,K_{2}, and σ from a given time series. The results show that by using this approach, we are able to achieve statistically reliable estimations of those invariants.

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