173 research outputs found

    Data centre optimisation enhanced by software defined networking

    Get PDF
    Contemporary Cloud Computing infrastructures are being challenged by an increasing demand for evolved cloud services characterised by heterogeneous performance requirements including real-time, data-intensive and highly dynamic workloads. The classical way to deal with dynamicity is to scale computing and network resources horizontally. However, these techniques must be coupled effectively with advanced routing and switching in a multi-path environment, mixed with a high degree of flexibility to support dynamic adaptation and live-migration of virtual machines (VMs). We propose a management strategy to jointly optimise computing and networking resources in cloud infrastructures, where Software Defined Networking (SDN) plays a key enabling role

    Produtividade e qualidade do caldo de cultivares de cana-de-açúcar em arranjos de espaçamentos entre fileiras no cerrado

    Get PDF
    Trabalho de conclusão de curso (graduação)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, 2017.Na atualidade o setor de sucroenergético é o nosso mais importante meio de geração de energias renováveis, a cana de açúcar é também responsável pelo fornecimento do açúcar brasileiro e de grande parte do mundo, tornando o seu papel ainda mais amplo na indústria e no comercio internacional. O objetivo desse trabalho foi avaliar características tecnológicas da cana de açúcar em diversos espaçamentos com duas cultivares (IAC 91-1099 e RB 86-7515). O experimento foi conduzido em condições de campo no Centro de Pesquisa Agropecuária dos Cerrados-CPAC no período de de julho de 2013 a outubro de 2015. Foram avaliados as cultivares de cana-de-açúcar IAC 91-1099 e RB 86-7515, ambas submetidas aos espaçamentos estreito, base larga, normal e fileira dupla. As características avaliadas em campo foram produtividade de cana planta e cana soca, produtividade de açúcar, °Brix, Fibra e Pol da cana. Utilizou-se o delineamento em blocos casualizados em esquema fatorial com médias comparadas pelo teste de Tukey a 5%. Os resultados mostraram que não houve diferença significativa de produtividade dentro de espaçamentos e cultivares, tanto para cana planta quanto para cana soca. Na avaliação tecnológica observou-se que não houve diferença estatística para °Brix, Fibra e Pol da Cana dentro de espaçamento, mas houve diferença significativa de Pol da Cana dentro de cultivar. AR (açúcares redutores) mostrou diferença significativa, tanto para cultivar quanto para espaçamento. ATR (açúcar total recuperável) e produtividade de açúcar não apresentaram diferenças significativas dentro de espaçamentos, porém apresentaram diferença significativa para cultivares. Como conclusões o espaçamento não influencia na produtividade das cultivares, tanto para cana planta quanto para cana soca. A qualidade do caldo (°Brix, Pol da Cana e Fibra) não demontra diferença entre cultivar x espaçamento, exceto o Pol da Cana é menor na cultivar IAC 91-1099. O teor de AR (açúcares redutores) apresenta diferença entre cultivares e nos espaçamentos entre fileiras. A cultivar RB 86-7515 apresenta maior valor para ATR (açúcar total recuperável) do que a cultivar IAC 91-1099

    Bison Influences on Composition and Diversity of Riparian Plant Communities in Yellowstone National Park

    Get PDF
    Riparian zones are among the most biologically diverse ecosystems in the Intermountain West, USA, and provide valuable ecosystem services, including high rates of biotic productivity, nutrient processing, and carbon storage. Thus, their sustainability is a high priority for land managers. Large ungulates affect composition and structure of riparian/stream ecosystems through herbivory and physical effects, via trailing and trampling. Bison (Bison bison) in Yellowstone National Park (YNP) have been characterized as ecosystem engineers because of their demonstrated effects on phenology, aboveground productivity of grasses, and woody vegetation structure. Bison have greatly increased in numbers during the last two decades and spend large periods of time in the broad open floodplains of the Northern Range of the Park, where they are hypothesized to have multiple effects on plant species composition and diversity. We sampled indicators of bison use as well as riparian vegetation composition, diversity, and structure along eight headwater streams within YNP\u27s Northern Range. Total fecal density ranged from 333 to 1833 fecal chips and/or piles/ha, stubble heights ranged from 7 to 49 cm, and streambank disturbance ranged from 9% to 62%. High levels of bison use were positively correlated with exotic species dominance and negatively correlated with species richness, native species diversity, willow (Salix spp.) cover, and wetland species dominance. At three sites, the intensity of bison use exceeded recommended utilization thresholds to avoid degradation of streams and riparian zones on public lands. The influences of large herbivores, principally bison, on vegetation composition and structure suggest the cumulative effects of the current densities on the Northern Range are contributing to biotic impoverishment, representing the loss of ecosystem services that are provided by native riparian plant communities. In addition, contemporary levels of bison use may be exacerbating climate change effects as observed through ungulate-related shifts in composition toward plant assemblages adapted to warmer and drier conditions. However, the resilience of native riparian vegetation suggests that sites currently heavily utilized by bison would have the potential for recovery with a reduction in pressure by this herbivore

    Componentes morfológicos e de rendimento de duas variedades de cana-de-açucar em espaçamentos de plantio simples e duplos

    Get PDF
    Orientador : Prof. Dr. Ricardo Augusto de OliveiraCo-orientador : Prof. Dr. Edelclaiton DarosDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Agronomia. Defesa: Curitiba, 28/02/2012Bibliografia: fls. 81-82Área de concentração: Produção vegetalResumo: O presente trabalho teve por objetivo, estudar o comportamento de duas variedades de cana-de-açúcar, em relação a 11 espaçamentos diferentes de plantio, simples e duplos, em cana de primeira soca. Foram realizados dois experimentos ao noroeste do Paraná, no município de Itambé, em área de ocorrência de solos argilosos de alta fertilidade natural. As variedades utilizadas foram RB855453 e SP81-3250, alocadas em áreas experimentais separadas, porém presentes no mesmo ambiente de estudo. Os tratamentos foram constituídos pelos espaçamentos de plantio simples de 1,00m, 1,20m, 1,40m, 1,60m, 1,80m e 2,00m, assim como os espaçamentos duplos de base estreita de 1,20 x 0,40m, 1,20 x 0,60m, 1,20 x 0,80m, seguidos dos espaçamentos duplos de base larga de 1,40 x 0,40m e 1,40 x 0,60. As características avaliadas foram os componentes de rendimento toneladas de cana.ha-1 (TCH), número de colmos por metro linear (NCM), massa média de colmos (M1C), número de colmos.m-², toneladas de açúcares redutores totais.ha-1 e os componentes morfológicos da planta diâmetro médio de colmos, estatura de colmos, área foliar (AF) e índice de área foliar (IAF). Os resultados obtidos pela análise de variância e contrastes ortogonais de médias, foram comprovados pelo teste F ao nível de 5% de probabilidade, realizados pelo software SISVAR. Procederam-se também análises complementares por correlação de Pearson e teste de associação entre as variáveis de estudo, comprovadas pelo teste t, em nível de 5% de probabilidade. Os resultados comprovaram que o melhor espaçamento em cana de primeira soca, para a variedade SP81-3250, neste ambiente de estudo, foi o espaçamento de 1,00 m simples, com 199 toneladas de cana.ha-1. Por sua vez, o experimento com a variedade RB855453, revelou que o espaçamento que propiciou maior produção de colmos por área, foi o espaçamento duplo de base larga de 1,40 x 0,40 (212 t.cana.ha-1). No espaçamento simples, para ambos os experimentos, assim como para a variedade RB855453, como para a SP81-3250, ocorreram incrementos de 81 toneladas de cana.ha-1 e 30 toneladas de cana.ha-1, respectivamente, a cada metro em que se reduz a distância entre os sulcos de plantio. Em ambas as variedades ocorreram, nos distintos experimentos, comportamentos adversos quanto ao IAF e estatura de colmos, influenciados pelo número de colmos por área, repercutindo diretamente na produtividade.Abstract: This work aimed to study the behavior of two varieties of cane sugar, compared to 11 different planting spacings, single and double in the first ratoon cane. Two experiments were conducted to the northwest of Paraná, in the municipality of Itambé in the area of occurrence of clay soils of high natural fertility. The varieties used were RB855453 and SP81-3250, placed in separate experimental areas, but present in the same study environment. The treatments consisted of the simple planting spacings of 1.00 m, 1.20 m, 1.40 m, 1.60 m, 1.80 m and 2.00 m, as well as double spacing narrow base of 1.20 x 0.40 m , 1.20 x 0.60 m, 1.20 x 0.80 m, followed by broadbased double spacing of 1.40 m and 1.40 x 0.40 x 0.60. The characteristics evaluated were the yield tons of cana.ha-1 (TCH), number of stems per meter (NCM), mean stalk weight (M1C), number of square-colmos.m, tons of total reducing sugars . ha-1 and morphological components of the plant stalk diameter, stalk height, leaf area (LA) and leaf area index (LAI). The results obtained by analysis of variance and orthogonal contrasts of means were confirmed by F test at 5% probability SISVAR performed by software. We conducted additional analyzes also by Pearson correlation and test of association between the study variables, as proven by t test at 5% probability. The results showed that the best spacing in the first ratoon cane, for the variety SP81-3250, this study environment, the spacing was 1.00 m simple, with 199 tons of cana.ha-1. In turn, the experiment with a variety RB855453 revealed that the spacing that resulted in higher straw yield per area, was the broad-based double spacing of 1.40 x 0.40 (212 t.cana.ha-1). In spaced, for both experiments, as well as to the variety RB855453, as for the SP81-3250, there was an increase of 81 tonnes of cana.ha-1 and 30 tons of cana.ha-1, respectively, each meter in which reduces the distance between the planting rows. In both varieties occurred in different experiments, adverse behaviors for LAI and height of culms, influenced by the number of stems per unit area has a direct impact on productivity

    Performance evaluation of cetacean species distribution models developed using generalized additive models and boosted regression trees

    Get PDF
    Species distribution models (SDMs) are important management tools for highly mobile marine species because they provide spatially and temporally explicit information on animal distribution. Two prevalent modeling frameworks used to develop SDMs for marine species are generalized additive models (GAMs) and boosted regression trees (BRTs), but comparative studies have rarely been conducted; most rely on presence-only data; and few have explored how features such as species distribution characteristics affect model performance. Since the majority of marine species BRTs have been used to predict habitat suitability, we first compared BRTs to GAMs that used presence/absence as the response variable. We then compared results from these habitat suitability models to GAMs that predict species density (animals per km2) because density models built with a subset of the data used here have previously received extensive validation. We compared both the explanatory power (i.e., model goodness of fit) and predictive power (i.e., performance on a novel dataset) of the GAMs and BRTs for a taxonomically diverse suite of cetacean species using a robust set of systematic survey data (1991–2014) within the California Current Ecosystem. Both BRTs and GAMs were successful at describing overall distribution patterns throughout the study area for the majority of species considered, but when predicting on novel data, the density GAMs exhibited substantially greater predictive power than both the presence/absence GAMs and BRTs, likely due to both the different response variables and fitting algorithms. Our results provide an improved understanding of some of the strengths and limitations of models developed using these two methods. These results can be used by modelers developing SDMs and resource managers tasked with the spatial management of marine species to determine the best modeling technique for their question of interest

    Caracterização de clones de cana-de-açúcar (Saccharum spp) em Paranavaí e Pelotas.

    Get PDF
    Dissertação (Mestrado) - Programa de Pós-Graduação em Sistemas de Produção Agrícola Familiar. Universidade Federal de Pelotas, Pelotas, RS. Orientador: Sergio Delmar dos Anjos e Silva CPACT; Co-Orientadores: Luis Antonio Verissimo Corrêa. UFPel; Ricardo Augusto de Oliveira. UFPR

    La Traducció genètica mitocondrial i malalties associades

    Get PDF
    En humans, com en la majoria d'organismes eucariotes, la síntesi proteica té lloc simultàniament al citoplasma i en orgànuls que posseeixen un genoma propi. Els mitocondris requereixen una maquinària traduccional pròpia per sintetitzar els tretze polipèptids, codificats al genoma mitocondrial, que formen part dels complexos de la cadena respiratòria i la fosforilació oxidativa responsables de proporcionar energia a la cèl·lula. Els elements que componen aquesta maquinària es troben codificats tant al genoma mitocondrial com al nuclear i participen de manera coordinada en la traducció genètica. Mutacions en els gens que codifiquen aquests factors de l'aparell de traducció genètica mitocondrial desencadenen un ampli ventall de malalties greus en humans, caracteritzades per símptomes heterogenis que en dificulten el diagnòstic i tractament. Hi ha malalties mitocondrials humanes causades per mutacions en el DNA mitocondrial que afecten específicament els tRNA i rRNA i, a més, s'han descrit mutacions en proteïnes mitocondrials codificades en el genoma nuclear, entre les quals es troben mutacions en factors de traducció, enzims de processament i modificació dels tRNA, proteïnes mitoribosòmiques i aminoacil-tRNA-sintetases mitocondrials. La complexitat de les malalties mitocondrials, la varietat de símptomes que causen i la dificultat de manipular genèticament el DNA mitocondrial compliquen la recerca relacionada amb aquestes malalties i justifiquen la generació de models animals que permetin caracteritzar-les i desenvolupar noves estratègies terapèutiques.In humans, as in the majority of eukaryotic organisms, protein synthesis occurs simultaneously in the cytoplasm and in those organelles that possess their own genome. Mitochondria require its own translational machinery in order to synthesize the 13 polypeptides, encoded in the mitochondrial genome, which are part of the respiratory chain and the oxidative phosphorylation complexes, responsible for supplying energy to the cell. The elements that compose this machinery are encoded both in the mitochondrial and the nuclear genome, and participate in gene translation in a coordinate manner. Mutations in genes that code for these factors of the gene translation apparatus trigger a wide range of severe pathologies in humans, characterized by heterogeneous symptoms that difficult their diagnostic and treatment. There exist human mitochondrial diseases caused by mutations in the mitochondrial DNA which specifically affect tRNA and rRNA and, additionally, mutations in nuclear encoded mitochondrial proteins have been described, among which are mutations in translation factors, enzymes involved in tRNA processing and modification, mitoribosomal proteins, and aminoacyl-tRNA synthetases. The complexity of mitochondrial pathologies, the variety of symptoms they cause, and the difficulty to manipulate mitochondrial DNA complicate the research related to these diseases and justify the generation of animal models that allow their characterization and the development of new therapeutic strategies
    corecore