Influência do coeficiente de difusão na qualidade da água em trecho de vazão reduzida

In some hydroelectric plants, downstream of the dams, there is the formation of reduced instream flow. Normally, dams structures with sills are added to increase the width of the channel and, consequently, reduce environmental impacts. This hydraulic configuration increases the liquid depth and reduces the average velocity, which causes more importance of the diffusive term in the behavior of the water quality parameters along the reduce instream flow. The focus of the study is the Capim Branco I Hydroelectric Power Plant, located in the lower course of the Araguari River, Triângulo Mineiro, which has 9 km of length and five small structures with sills. The simulations of OD, DBO, organic nitrogen, ammonia, nitrate and phosphorus parameters were performed in the AQUATOOL tool, from October 2009 to September 2010. The simulations for the diffusion coefficients E equal to 5, 10, 15 and 20 m2/s were compared with simulations of E equal to zero. The reduced value of E results greater influence on the behavior of water quality parameters. The pollutant load of the Marimbondo stream increased considerably the variation of BOD, phosphorus and organic nitrogen (dry and rainy period, respectively, 2% and 4% for BOD, 6% and 7% for phosphorus and 5% and 6 % for organic nitrogen). The DO variation was reduced in the dry and rainy season, remaining less than 1% in the majority of reduce instream flow. The nitrification process resulted in high ammonia variations, with a peak of 10% in the dry period and 14% in the rainy season, and a high nitrate variation, with a peak of 16% in the dry period and 18% in the rainy season. Towards the impact of E coefficient on the behavior of the parameters, it is suggested that this coefficient is previously obtained in the field by experimental methods with tracers.Em algumas instalações hidrelétricas existe a formação de trecho de vazão reduzida a jusante do barramento. Normalmente são introduzidas estruturas de barramento com soleiras para aumentar a largura do canal e, consequentemente, diminuir os impactos ambientais. Esta configuração hidráulica aumenta a profundidade líquida e reduz a velocidade média do escoamento, o que faz com que o termo difusivo ganhe importância no comportamento dos parâmetros de qualidade da água ao longo do trecho de vazão reduzida. O foco do estudo é o trecho de vazão reduzida da Central Hidrelétrica Capim Branco I, localizado no baixo curso do rio Araguari, Triângulo Mineiro e que possui a extensão de 9 km e cinco pequenos barramentos. As simulações dos parâmetros OD, DBO, nitrogênio orgânico, amônia, nitrato e fósforo total foram realizadas na ferramenta AQUATOOL, no período de outubro de 2009 até setembro de 2010. As simulações para os coeficientes de difusão E iguais a 5, 10, 15 e 20 m2/s foram comparadas com os simulados para E igual a zero. O valor reduzido de E traz maior influência sobre o comportamento dos parâmetros de qualidade da água. O incremento de carga poluidora do córrego Marimbondo aumentou consideravelmente a variação de DBO, fósforo total e nitrogênio orgânico (para o período seco e chuvoso, respectivamente, 2% e 4% para a DBO, 6% e 7% para o fósforo total e 5% e 6% para o nitrogênio orgânico). A variação de OD foi reduzida no período seco e chuvoso, mantendo-se inferior a 1% na maioria do trecho de vazão reduzida. O processo de nitrificação ocasionou elevadas variações de amônia, com pico de 10% no período seco e de 14% no chuvoso, além de elevada variação de nitrato, com pico de 16% no período seco e 18% no chuvoso. Diante do impacto de E no comportamento dos parâmetros, sugere-se que este coeficiente seja previamente obtido em campo por meio de métodos experimentais com traçadores

Detailed modelling and analysis of digital mho distance relay with single-pole operation

This paper introduces a methodology for modelling a digital admittance-type distance relay using PSCAD/EMTDC. The proposed distance relay was tested in a simulation of the Brazilian power grid with predetermined fault scenarios. The goal of this paper is to make a detailed evaluation of the mho distance relay. The main aspects include the correct operation of the distance relay, fault resistance effects on the mho characteristics, and the fault detection time of this relay. A new approach to analyse the fault detection time is presented, considering several simulated fault scenarios. The results demonstrate that the fault resistance influences the fault detection time and severely affects the distance relay’s general performance. The fault detection time is not constant. It varies within a time interval, considering different fault types, fault locations, and fault resistances. The confidence interval calculation provides a detailed range of the fault detection time, considering its upper and lower limits

A AGROINDÚSTRIA DE ALIMENTOS DE FRUTAS E HORTALIÇAS NO NORDESTE E NORTE DOS ESTADOS DE MINAS GERAIS E ESPÍRITO SANTO

A Região Nordeste tornou-se a maior produtora de frutas irrigadas e de sequeiro, resultando na instalação de unidades de processamento distribuídas em todos os estados da área de atuação do Banco do Nordeste do Brasil – BNB (Região Nordeste e norte dos Estados de Minas Gerais e Espírito Santo). Como principal órgão de desenvolvimento dessa Região, o BNB necessita conhecer as características e problemas do processamento agroindustrial de alimentos em sua área de atuação, contribuindo para suas ações e políticas em relação ao setor, sendo este o objetivo desta pesquisa. As fontes de informações para o trabalho foram entrevistas com agroindustriais, intermediários, produtores rurais, centros de pesquisa e supermercados. Os resultados permitem concluir que existem diferenças entre as categorias de agroindústria pesquisadas, principalmente no que diz respeito às formas de gestão, organização, linhas de produção, acesso à tecnologia, informações e participação no mercado. --------------------------------------------------The Northeast Region became it bigger producer of irrigated fruits and dry land, resulting in the installation of units of processing distributed in all the states of the area of performance of the Banco do Nordeste do Brasil - BNB (Northeast Region and north of the States of Minas Gerais and Espirito Santo). As main agency of development of this Region, the BNB needs to know the characteristics and problems of the agro-industrial food processing in its area of performance, contributing for its action and politics in relation to the sector, being this the objective of this research. The sources of information for the work had been agro-industrial, intermediate, producing interviews with agricultural, centers of research and supermarkets. The results allow to conclude that differences between the searched categories of agroindustry exist, mainly in that it says respect to the management forms, organization, lines of production, access to the technology, information and participation in the market.Agroindústria de alimentos, Processamento de frutas e hortaliças, Região Nordeste, Foods’ agroindustry, Processing of fruits and vegetable. Northeast Region, Agribusiness, Crop Production/Industries,

A AGROINDÚSTRIA DE ALIMENTOS DERIVADOS DE CACAU NO NORDESTE BRASILEIRO

O objetivo deste artigo é caracterizar o setor agroindustrial de alimentos derivados de cacau no Nordeste Brasileiro. O trabalho foi desenvolvido com base na metodologia de pesquisa descritiva e explicativa, focado na identificação das características e nas inter-relações entre os elos dessa atividade econômica no Nordeste. A agroindústria de derivados de cacau no Nordeste tem se expandido e apresentado maior integração com as cadeias produtivas do setor rural. Porém, o fortalecimento do setor agroindustrial depende, ainda, do fornecimento de matérias-primas com qualidade e regularidade; estabelecimento, disseminação e fiscalização de controles de qualidade e de normas e padrões sanitários; profissionalização de dirigentes nas áreas administrativas e de agronegócios; qualificação da mão-de-obra; assistência técnica com qualidade; regulamentação da concorrência; simplificação de normas fitossanitárias; educação e conscientização de consumidores, além da elevação de renda da população.---------------------------------------------------------------- ---------------The objective of this article is to characterize the agro-industrial food sector derived of cacao from Brazilian Northeast. The work was developed on the basis of the characteristics and the Inter-relations between the links of this economic activity from northeast. The agro-industry of derivatives of cacao in the Northeast if has expanded and presented bigger integration with the productive chains of the agricultural sector. However, to fortify the agro-industrial sector depends, still, of the raw material supply with quality and regularity; establishment, dissemination and fiscalization of norm and quality control and sanitary standards; professionalization of controllers in the administrative areas and agribusiness; qualification of the worker; assistance technique with quality; regulation of the competition; simplification of fitossanitaries norms; education and awareness of consumers, beyond the rise of income of the population.Agroindústria, Cacau, Nordeste Brasileiro, Agro-industry, Cacao, Brazilian Northeast, Agribusiness, Crop Production/Industries,

Classificação da capacidade produtiva de povoamentos não desbastados de clones de eucalipto

The objective of this work was to develop and propose a procedure for stratification of unthinned eucalyptus clone forest, in order to classify its productive capacity. Data from 70 clones, distributed into 5,020 permanent plots of continuous forest inventories, were used with at least three annual measurements for each clone. For all clones, the Schumacher model was fit for the variables: basal area; dominant height; mean diameter; and commercial volume, with bark. The Tocher method was used to group clones displaying similar dominant height growth tendencies, and this procedure showed to be efficient. Site index estimate, for clones with less than tree measurements, can be determined from information regarding dominant height, mean diameter, basal area and commercial volume obtained from continuous forest inventories.O objetivo deste trabalho foi desenvolver e propor um procedimento para a estratificação de florestas de clones de eucalipto não desbastados, para a classificação de sua capacidade produtiva. Utilizaram-se dados provenientes de 70 clones, distribuídos em 5.020 parcelas permanentes de inventários florestais contínuos, com pelo menos três medições, de periodicidade anual, em cada clone. Para todos os clones, foi ajustado o modelo de Schumacher para as variáveis: área basal; altura dominante; diâmetro médio; e volume comercial, com casca. Com esses parâmetros, foi utilizado o método de Tocher, que se mostrou eficiente para agrupar clones com tendências semelhantes de crescimento em altura dominante. A estimativa de índice de local, para clones com menos de três medições, pode ser determinada a partir das informações de altura dominante, diâmetro médio, área basal e volume, obtidas do inventário florestal contínuo de outros clones

Estimativa do Volume e da Pressão de Turgescência do Estômato de Vicia Faba ao Longo do Dia

http://dx.doi.org/10.5902/2179460X14849The stomata control the water output of the plant, this control depends on the stomatic volume variation which in turn depends on the variation of the stomatic turgor pressure. Therefore, the aim of this study was to estimate the volume and turgor pressure of the stomata Vicia faba through the day. The biophysical parameters of the stomata Vicia faba found in the literature and Van't Hoff equation were utilized to estimate the osmotic pressure generated by the osmotically active solutes (potassium, chloro and sucrose). The resulting values ​​are in agreement with literature and can be used in simulations, such as the study of leaf transpiration through the equation Weyers and Meidner (1990).  Os estômatos controlam a saída de água da planta, esse controle depende da variação do volume estomático que por sua vez depende da variação da pressão de turgescência estomática. Dessa forma o presente trabalho teve como objetivo estimar o volume e a pressão de turgescência do par de células guarda estomáticas da Vicia faba ao longo do dia. Foram utilizados os parâmetros biofísicos do estômato da Vicia faba encontrados na literatura e a equação de Van’t Hoff para estimar a pressão osmótica gerada pelos solutos osmoticamente ativos (potássio, sacarose e cloro). Os valores resultantes estão de acordo com a literatura e podem ser utilizados em simulações, como, por exemplo, modelagem da transpiração foliar a partir da equação de Weyers e Meidner (1990)

Is the Frequency in Somatosensory Electrical Stimulation the Key

Somatosensory electrical stimulation (SES) has been proposed as an approach to treat patients with sensory-motor impairment such as spasticity. However, there is still no consensus regarding which would be the adequate SES parameters to treat those deficits. Therefore, the aim of this study was to evaluate the effects of applying SES over the forearm muscles at four different frequencies of stimulation (3, 30, 150, and 300 Hz) and in two intervals of time (5′ and 30′) by means of transcranial magnetic stimulation and Hoffmann’s reflex (H-reflex) in healthy volunteers (Experiments  I and II). A group of stroke patients (Experiment  III) was also preliminary evaluated to ascertain SES effects at a low frequency (3 Hz) applied for 30′ over the forearm spastic flexors muscles by measuring the wrist joint passive torque. Motor evoked potentials and the H-reflex were collected from different forearm and hand muscles immediately before and after SES and up to 5′ (Experiment  I) and 10′ (Experiments  I and II) later. None of the investigated frequencies of SES was able to operate as a key in switching modulatory effects in the central nervous system of healthy volunteers and stroke patients with spasticity

Effect of salicylic acid on cowpea seedlings under saline stress

The aim of this work was applying salicylic acid (SA) in cowpea seedlings under saline stress. The experiment took place in the seed laboratory of the Universidade Federal Rural da Amazônia with a completely randomized experimental design in a 2 x 2 x 3 factorial scheme, with two bean cultivars (Canapu and Pingo-de-ouro), two levels of salicylic acid (0, and 0.50 mM) and three salt stress levels (0, 25, 50 mM). The seeds were previously soaked in salicylic acid (0 and 0.50 mM) for a period of 12 hours and then placed in germitest paper rolls for treatments with NaCl (0, 25, 50 mM) for a period of 12 days at room temperature constant 27 °C. There was a significant effect of cultivars, AS dose and NaCl concentrations and their interactions on most of the analyzed variables. Root and leaf proline concentrations were higher in pingo-de-ouro cultivar, Canapu cultivar had better performance in biomass accumulation. Salicylic acid reduced proteins in the leaves by 13.33%, while in the root there was an increase of 12.61%, ammonium concentrations reduced in the roots by 11.9%. When applied to salinity (25 and 50 mM) there was an increase of proteins in the leaves 40.83% and 27.48% respectively, and a reduction of amino acids of 30.24 and 25.24% in NaCl dosages (25 and 50 mM) respectively. Salinity reduced biomass accumulation and interfered with cellular solute production. However, the application of salicylic acid promoted salt stress tolerance in Canapu cultivar

Biochemical Characterization of an In-House Coccidioides Antigen: Perspectives for the Immunodiagnosis of Coccidioidomycosis

The objective of this study was to evaluate the reactivity of an in-house antigen, extracted from a strain of C. posadasii isolated in northeastern Brazil, by radial immunodiffusion and Western blotting, as well as to establish its biochemical characterization. the protein antigen was initially extracted with the use of solid ammonium sulfate and characterized by 1-D electrophoresis. Subsequently, it was tested by means of double radial immunodiffusion and Western blotting. A positive reaction was observed against the antigen by both immunodiagnostic techniques tested on sera from patients suffering from coccidioidomycosis. Besides this, two immunoreactive protein bands were observed and were revealed to be a beta-glucosidase and a glutamine synthetase after sequencing of the respective N-terminal regions. Our in-house Coccidioides antigen can be promising as a quick and low-cost diagnostic tool without the risk of direct manipulation of the microorganism.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordination for the Improvement of Higher Education PersonnelUniv Fed Ceara, Specialized Med Mycol Ctr, Sch Med, BR-60430270 Fortaleza, Ceara, BrazilUniv Estadual Ceara, Postgrad Program Vet Sci, Sch Vet Med, BR-60740000 Fortaleza, Ceara, BrazilUniv Fed Ceara, Dept Biochem & Mol Biol, BR-60455760 Fortaleza, Ceara, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, BR-04021001 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Immunol & Parasitol, BR-04021001 São Paulo, BrazilCNPq: 302574/2009-3CNPq: 306637/2010-3Coordination for the Improvement of Higher Education Personnel: CAPES/PNPD2103/2009Web of Scienc