78 research outputs found

    Cloning, in silico structural characterization and expression analysis of MfAtr4, an ABC transporter from the banana pathogen Mycosphaerella fijiensis

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    ABC transporters are membrane proteins that use the energy released from the hydrolysis of ATP to drive the transport of compounds across biological membranes. In some plants, pathogenic fungi ABC transporters play a role as virulence factors by mediating the export of plant defense compounds or fungal virulence factors. Mycosphaerella fijiensis, the causal agent of black Sigatoka disease in banana, is the main constraint for the banana industry worldwide. So far, little is known about molecular mechanism that it uses to infect the host. In this study, degenerated primers designed from fungal ABC transporters known to be involved in virulence were used to isolate homologs from M. fijiensis. Here, we reported the full cloning of MfAtr4 a putative ortholog of MgAtr4, an ABC transporter of the related Mycosphaerella graminicola with a function in virulence. Similarities and differences with its presumed ortholog MgAtr4 are described, and the putative function of MfAtr4 are discussed. Analysis of MfAtr4 gene expression in field banana samples exhibiting visible symptoms of black Sigatoka disease indicated a higher expression of MfAtr4 during the first symptomatic stages in comparison to the late necrotrophic phases, suggesting a role for MfAtr4 in the early stages of pathogenic development of M. fijiensis.Key words: ABC transporters, virulence factors, MgAtr4 ortholog, Mycosphaerella fijiensis, black Sigatoka, Musa sp

    Herramienta de Identificación Paramétrica, Validación y Sintonización de Reguladores de Velocidad Mediante Algoritmos de Optimización Heurísticos

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    En la actualidad, la operación del sistema eléctrico ecuatoriano experimenta varios desafíos técnicos, tales como: 1) la integración de sistemas eléctricos vecinos en el Sistema de Interconexión Eléctrica Andina (SINEA) y 2) la diversificación de las fuentes primarias de energía. Bajo estas nuevas condiciones operativas, la seguridad dinámica puede ser afectada por problemas de estabilidad de frecuencia. Con base en la regulación de frecuencia se busca, a través de mecanismos de control y reservas de generación disponible, responder en forma adecuada a las exigencias del sistema eléctrico. Bajo este contexto, es necesario el desarrollo de metodologías que permitan la respuesta rápida y precisa de los equipos de control potencia - frecuencia, tales como los reguladores de velocidad, los cuales actúan de forma local en los generadores para realizar la Regulación Primaria de Frecuencia. Con estos antecedentes, se propone una metodología, basada en métodos heurísticos de optimización, para el desarrollo de una herramienta que permita realizar la identificación paramétrica y ajuste de los reguladores de velocidad. Con las mediciones obtenidas en base a la metodología propuesta, la herramienta desarrollada logró de manera efectiva realizar la identificación y validación del sistema de regulación de velocidad de la central CCS así como proponer nuevos parámetros que mejoran la respuesta del sistema identificado.

    Suspensión condicional de la pena en procedimientos abreviados: ¿Derecho o abuso?

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    Introduction. Conditional suspension of sentence is a legal institution that allows a person convicted of a crime not to serve a prison sentence, provided that certain conditions are met. In Ecuador, this figure is regulated by Article 74 of the Comprehensive Organic Criminal Code (COIP). In 2016, the National Court of Justice of Ecuador issued Resolution No. 02-2016, in which it ruled that conditional suspension of the sentence is not appropriate in cases resolved through abbreviated proceedings. This resolution has been criticized by some sectors, which consider that it violates the rights of convicted persons.  Objective. The objective of this paper is to analyze whether the resolution of the National Court of Justice violates the rights of persons convicted of a crime through an abbreviated procedure.  Methodology. An analytical-synthetic, inductive-deductive method with a qualitative approach was used for the development of this work. A bibliographic review of the regulations and jurisprudence applicable to the subject was carried out.  Results. The analysis of the regulations and jurisprudence applicable to the issue leads to the conclusion that the resolution of the National Court of Justice violates the rights of persons convicted of a crime through an abbreviated procedure. The conditional suspension of the sentence is a right of convicted persons, recognized by the Constitution and international human rights instruments. Conclusion. The resolution of the National Court of Justice violates the rights of persons convicted of a crime through an abbreviated procedure. This resolution must be revoked to guarantee the right to social reintegration of these persons.Introducción. La suspensión condicional de la pena es una institución jurídica que permite a una persona condenada por un delito no cumplir la pena de prisión, siempre que cumpla con ciertas condiciones. En el Ecuador, esta figura está regulada por el artículo 74 del Código Orgánico Integral Penal (COIP). En el año 2016, la Corte Nacional de Justicia del Ecuador emitió la Resolución No. 02-2016, en la que resolvió que la suspensión condicional de la pena no es procedente en los casos resueltos mediante procedimiento abreviado. Esta resolución ha sido criticada por algunos sectores, que consideran que vulnera los derechos de las personas condenadas. Objetivo. El objetivo de este trabajo es analizar si la resolución de la Corte Nacional de Justicia vulnera los derechos de las personas condenadas por un delito mediante procedimiento abreviado. Metodología. Para el desarrollo de este trabajo se utilizó un método analítico-sintético, inductivo-deductivo con un enfoque cualitativo. Se realizó una revisión bibliográfica de la normativa y la jurisprudencia aplicable al tema. Resultados. El análisis de la normativa y la jurisprudencia aplicable al tema permite concluir que la resolución de la Corte Nacional de Justicia vulnera los derechos de las personas condenadas por un delito mediante procedimiento abreviado. La suspensión condicional de la pena es un derecho de las personas condenadas, reconocido por la Constitución y los instrumentos internacionales de derechos humanos. Conclusión. La resolución de la Corte Nacional de Justicia vulnera los derechos de las personas condenadas por un delito mediante procedimiento abreviado. Esta resolución debe ser revocada para garantizar el derecho a la reinserción social de estas personas. Área de estudio general: Derecho. Área de estudio específica: Derecho penal y procesal penal

    Carbonyl Iron Foam Surfaces Modified with Poly (L-Lysine) As Smart Surface for Bone Implant

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    This article presents the surface modification of iron Fe (110) surfaces with Poly-L-Lysine (PLL) with the aim of preparing carbonyl iron bone implants which are less corrosive and more compatible with fibroblast cells. The cytocompatibility of modified surfaces with commercially available α-PLL and electrodeposited ε-PLL was compared by combination of DFT computational simulations with experimental electrochemical and cell adhesion studies to obtain “smart” surface application. Experimental study of fibroblasts adhesion showed better viability of cells on ε-PLL than on α-PLL after modification of Fe surfaces as “smart” surfaces to obtain a different hydrophobicity. The porosity of Fe (110) prevented direct measurements of contact angle and therefore surface hydrophobicity was simulated with calculation of adsorption energies for Fe with both α-/ε- PLL structures. This technique was also employed to calculate the interaction of O-H bonds at the surface. The corrosion potential of Fe (110) with superficially modified ε-PLL was shifted by 0.088V compared to the bare iron surface, thus indicating a stronger resistance to corrosion. The results suggest that modification of Fe surface with ε-PLL has a more pronounced effect on cellular growth on this implant and that the slightly hydrophobic character of ε-PLL leads to better cell adhesion ability

    Regeneración natural de sitios de manglar degradado en respuesta a la restauración hidrológica = Natural regeneration of degraded mangrove sites in response to hydrological restoration

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    The mangroves of Laguna de Términos, Campeche have been affected by the loss of hydrological connection due to tropical storms and hurricanes. The objective of this study was to evaluate the natural regeneration in a degraded area, after having implemented actions of restoration through hydrological restoration. Three sampling sites with different times of restoration (1-3 years), and a preserved natural mangrove site as reference, were established. The sampling was carried out in the years 2014 to 2015. Forest structure (density, height), survival, growth rate of seedlings and environmental characteristics were measured. The relationship between the vegetation and environmental characteristics was determined using simple linear regressions and multidimensional scaling analysis. To determine the dispersal of seedlings, a mixed linear model of the seedling density vs distance vs time of restoration was generated. The results showed that distance to natural mangroves affects the seedling density. The phosphates concentration is related to survival, while the ammonia and sulphide concentration is negatively related to seedling density. The actions of hydrological restoration influenced the settlement and growth seedling of mangrove vegetation, therefore natural areas of mangroves and the water reconnection facilitated propagule dispersal towards the degraded areas, highlighting the importance of the inclusion of natural areas within the restoration projects

    Diversity of Haloquadratum and other haloarchaea in three, geographically distant, Australian saltern crystallizer ponds

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    Haloquadratum walsbyi is frequently a dominant member of the microbial communities in hypersaline waters. 16S rRNA gene sequences indicate that divergence within this species is very low but relatively few sites have been examined, particularly in the southern hemisphere. The diversity of Haloquadratum was examined in three coastal, but geographically distant saltern crystallizer ponds in Australia, using both culture-independent and culture-dependent methods. Two 97%-OTU, comprising Haloquadratum- and Halorubrum-related sequences, were shared by all three sites, with the former OTU representing about 40% of the sequences recovered at each site. Sequences 99.5% identical to that of Hqr. walsbyi C23T were present at all three sites and, overall, 98% of the Haloquadratum-related sequences displayed ≤2% divergence from that of the type strain. While haloarchaeal diversity at each site was relatively low (9–16 OTUs), seven phylogroups (clones and/or isolates) and 4 different clones showed ≤90% sequence identity to classified taxa, and appear to represent novel genera. Six of these branched together in phylogenetic tree reconstructions, forming a clade (MSP8-clade) whose members were only distantly related to classified taxa. Such sequences have only rarely been previously detected but were found at all three Australian crystallizers

    Biogeography at the limits of life: Do extremophilic microbial communities show biogeographical regionalization?

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    Aim Biogeographical regions are the fundamental geographical units for grouping Earth's biodiversity. Biogeographical regionalization has been demonstrated for many higher taxa, such as terrestrial plants and vertebrates, but not in microbial communities. Therefore, we sought to test empirically whether microbial communities, or taxa, show patterns consistent with biogeographical regionalization. Location Within halite (NaCl) crystals from coastal solar salterns of western Europe, the Mediterranean and east Africa. Time period Modern (2006–2013). Major taxa studied Archaea. Methods Using high-throughput Illumina amplicon sequencing, we generated the most high-resolution characterization of halite-associated archaeal communities to date, using samples from 17 locations. We grouped communities into biogeographical clusters based on community turnover to test whether these communities show biogeographical regionalization. To examine whether individual taxa, rather than communities, show biogeographical patterns, we also tested whether the relative abundance of individual genera may be indicative of a community's biogeographical origins using machine learning methods, specifically random forest classification. Results We found that the rate of community turnover was greatest over subregional spatial scales (< 500 km), whereas at regional spatial scales the turnover was independent of geographical distance. Biogeographical clusters of communities were either not statistically robust or lacked spatial coherence, inconsistent with biogeographical regionalization. However, we identified several archaeal genera that were good indicators of biogeographical origin, providing classification error rates of < 10%. Main conclusions Overall, our results provide little support for the concept of biogeographical regions in these extremophilic microbial communities, despite the fact that some taxa do show biogeographical patterns. We suggest that variable dispersal ability among the halite-associated Archaea may disrupt biogeographical patterns at the community level, preventing the formation of biogeographical regions. This means that the processes that lead to the formation of biogeographical regions operate differentially on individual microbial taxa rather than on entire communities

    The PREDICTS database: A global database of how local terrestrial biodiversity responds to human impacts

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    © 2014 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015. The collation of biodiversity datasets with broad taxonomic and biogeographic extents is necessary to understand historical declines and to project - and hopefully avert - future declines. We describe a newly collated database of more than 1.6 million biodiversity measurements from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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