971 resultados para Riachos tropicais


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Comunidades de Ephemeroptera, Plecoptera e Trichoptera (EPT) em substrato rochoso foram estudadas em dois riachos do Parque Estadual Intervales. Coletas com um amostrador de Surber (10 subamostras aleatórias, 1 m²) foram feitas mensalmente de setembro de 1999 a setembro de 2000 e trimestralmente de dezembro de 2000 a setembro de 2001 nos Ribeirões Bocaina e Água Comprida. A fauna de EPT do Ribeirão Bocaina foi mais diversificada e mais abundante do que a do Ribeirão Água Comprida. A fauna de EPT foi bastante diferente entre os dois riachos, tanto do ponto de vista da composição faunística quanto do ponto de vista funcional. Os resultados indicaram que não houve um padrão sazonal claro da variação temporal da densidade.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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A technological alternative for the correct disposal of tires is the use in the construction of embankment with soil and shredded tires. The use of waste tires in tropical soils requires prior knowledge of the properties and limitations of these materials. In this work, the results of an experimental program was devised to characterize the behavior of mixtures of waste tires and a lateritic soil. The residue used in this study is classified as tire buffings with an average size of 1.4 mm. The laboratory program included testing of particle size analysis, Atterberg limits, compaction, direct shear tests, permeability and confined compression tests with pure soil, pure tire and the mixtures. Proportions of 0% (pure soil), 10%, 20%, 40%, 50 % and 100% (pure tire) by weight were used. For the confining stress levels used in the study, the presence of tire residue provided a considerable increase in shear strength of the mixture. The maximum shear strength was obtained for a residue content of 40% by weight. Permeability tests on samples of waste under a confining stress of 100 kPa showed that the permeability increases significantly with increasing residue content until a residue content of 20%. The increase in permeability after that value showed to be negligible. Confined compression tests showed that the soil mixed with tire residue becomes more compressible than the pure soil. The secant constrained modulus (Msec) for the same vertical stress decreases with increasing percentage of residue.

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Dengue fever is an infectious disease that causes thousands of deaths each year in Brazil and other tropical countries. This work demonstrates that the irregularity in the supply of water by public water supply systems is a major factor that contributes to the proliferation of breeding sites of the mosquito that transmits dengue, due to the impossibility of removing water storage tanks. 31 points in the water supply network in thirteen districts of Natal, Brazil, were monitored by the installation of pressure gauges type Datalogger. The data about pressure showed deficiency in water supplies in many neighborhoods, forcing residents to accumulate water in tanks at ground level. In addition, It was observed that in neighborhoods with regular water supply, Infestation Index per type of container (ITR) of type A2 (Deposit ground level) was 0.00% and where there were failures in the supply of water , the ITR was high (above 50%). We believe that policies to combat dengue in Brazil should be reassessed so that more resources can be directed to the improvement of water supply systems and supply companies should be blamed for the problem too

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Experience in the use of stabilization ponds shows that this is a system with low cost, easy operation and maintenance and suitable for tropical countries. One of its disadvantages is due to high concentrations of suspended solids, mainly due to algal biomass in the effluents. Accordingly, the dissolved air flotation has been shown to be an efficient post-treatment technology. However, the efficiency of this process is related to coagulation and flocculation steps, as well as the adjustment of the involved variables in the process. The objective of this work was to evaluate the algae removal efficiency from wastewater stabilization ponds and the influence of the factors involved in the process using dissolved air flotation. For this, we used primary facultative and maturation effluents of ETE Ponta Negra in Natal. We did tests of coagulation, flocculation and flotation with the samples, using the equipment flotatest. In this process were tested coagulants aluminum sulfate and ferric chloride, and varied the factors pH, coagulant concentration, polymer concentration and rate of recirculation. At the end of the experiments were analyzed turbidity, suspended solids, color, COD and chlorophyll "a". These results were submitted to descriptive statistics to verify the efficiency of the process in general, and regression analysis to identify models that describe the process and demonstrate the factors that have greater influence on flotation. After step methodology, high values were found removal efficiency of suspended solids, reaching values greater than 90% in the best cases. It was concluded that flotation is more efficient in the facultative pond effluent using ferric chloride, and the variability of algae may negatively influence the process. Regression analyzes showed that pH is the most influential variable in the coagulation-flocculation-flotation, and its optimal value among the tested is 5.5 for both coagulants

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Registramos a incidência de parasitismo por vermes Mermithidae em larvas de Chironomus gr. decorus (Diptera: Chironomidae), no Rio dos Peixes, Dois Córregos, região centro-oeste do Estado de São Paulo, Brasil. Neste estudo, de um total de 791 larvas amostradas, 205 (25,9%) estavam infectadas por mermitídeos, indicando que larvas de Chironomidae são comumente parasitadas por vermes mermitídeos.

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Introduction: Cancer of the lip is very common in tropical countries, being noticeable the squamous cell carcinoma as the main histological type. Objective: Evaluate the socialdemographic profile, habits, occupation, clinical characteristics of the cancer lesions and the aftermath of treatment of the patients treated on the Luiz Antônio Hospital (Natal-RN). Design: Retrospective cohort. Methods: We analyzed 181 medical records of patients from the Luiz Antônio Cancer Hospital (Natal-RN) in the period between 1997 and 2004. The statistic evaluation of time between the diagnosis and the relapse or the cure of the patient were done through the Kaplan-Meier method and the comparison of survivor functions were done through the Log-rank test. Later, was estimated the proportional risk model of Cox. Results: The study population were composed by 69,1% males, 95,2% unlettered, the mean age of 66,5 years, 89,0% of smokers and 64,1% had an occupation involving sun exposure. In regard to the clinical characteristics, most lesions were in the lower lip (77,9%), the size of the tumor was smaller than 2 cm (51,8%), 92,6% had localized lesions. Were verified 16,3% of local relapse and 13% of regional. Almost the totally of the cases corresponded to squamous cell carcinoma (97,2%). We observed smaller accumulated probability of not occurrence of local relapse when the base and borders were free of lesions (p=0,041), as well as a smaller probability of regional relapse when the sort of treatment was surgery, associated with other therapeutics modalities (p=0,001). The patients with advanced pathologic stage (p=0,016), treated with surgery associated with other therapeutics modalities (p=0,001) and diameter above 4cm (p=0,019) presented a bigger possibility of any kind of relapse. The multivariable analysis pointed the complex treatments (surgery plus other therapeutics modalities) as a predictor variable for occurrence of new local lesions (p=0,001) and total (p=0,046), besides the age above 70 years to the regional relapse (p=0,050). Conclusion: Cancer of the lip occur in the lower lip, in males, smokers and individuals exposed to Sun light. The relapse was frequent, even being localized and without great consequences to the patient s health. The probability of relapse is related to the size and borders of the lesion and to the histological exam, as well as to the patient s age and complexity of the treatment chosen

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The objective of this study was to evaluate the quality of housing and the physical and chemical characteristics of meat from sheep raised on pasture Brachiaria brizantha and Panicum maximum. The experiment was conducted in the physical area of the Study Group on Forage (GEFOR), located in the Academic Unit Specialized in Agricultural Sciences - Federal University of Rio Grande do Norte - UFRN in Macaíba, RN, Brazil. We used 32 lambs SPRD, obtained from herds in the state, with liveweight (LW) of 24.5 kg were assigned randomly to four treatments consisting of tropical grasses, two cultivars of Brachiaria brizantha, Marandu and Piatã, and two of Panicum maximum, Aruana and Massai. The experimental area was 2.88 ha, divided into 4 paddocks of 0.72 ha, where each picket consisted of a farm and was divided into six plots of 0.12 ha, where the animals remained under rotational grazing. The period of adaptation to the pickets was seven days. At the beginning of the experiment the animals were weighed, identified with plastic earrings and necklaces colored according to the treatment, and treated against. The lambs were loose in the paddock at 8 am and collected at 16 hours, which returned to collective pens. During the time of grazing animals had free access to mineral supplement with monensin Ovinofós ® and water. Before entering the paddocks of pasture were sampled to characterize the chemical composition. Every seven days occurred at weighing, with fasting, to monitor the weight development. Cultivars Marandu, Aruana, Piatã and Massai were grazed for 133, 129, 143 and 142 days, respectively, until the lambs reach slaughter weight. Arriving at 32 kg lambs were evaluated subjectively for body condition score by, passed through fasting period, diet and water for 16 hours were slaughtered. Measurements were made in the inner and outer casings in addition to subjective evaluations regarding muscling, finish and quantity of pelvic-renal fat, then each was divided longitudinally into two half-carcases and cuts were made in the commercial left half, and after heavy calculated their income. Between the 12th and 13th thoracic vertebrae, was performed a cut to expose the cross section of the Longissimus dorsi, which was drawn on the rib eye area (REA) in transparent film. Fat thickness and extent of AOL GR were determined using a caliper. A tissue composition was determined by dissection of the legs. Analyzes were performed physical (color, cooking loss and shear force) and chemical composition of meat (moisture, ash, protein and lipids) in Longissimus dorsi muscle. Grazing tropical grass Brachiaria brizantha cvs. Marandu and Piatã and Panicum maximum cvs. Aruana and Massai can be used for lambs SRPD in the rainy season, because not alter the physico-chemical and chemical composition of meat

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The low quality of tropical pastures in the dry season justifies the use of dietary supplements to meet the nutritional needs of sheep to meat production. Therefore, the objective of this experiment was to evaluate the agronomic characteristics of massaigrass in the dry season and the effect of protein supplements in the performance and productivity of sheep to meat production grazing. The protein supplements evaluated were: soybean meal, Leucena hay, Gliricidia hay and multiple mixture. The animals were managed in massaigrass pastures under rotational stocking and supplemented daily. Were used 24 sheep ½ Santa Inês x ½ SPRD (without defined breed), males uncastrated, mean age 90 days in a completely randomized design. Performance of sheep was evaluated for average daily gain of live weight gain per area and stocking rate (animals of 25 kg/ha). The pasture was evaluated for forage mass of pre and post-grazing, the percentages of participation of morphological constituents and their nutritional values and rates of herbage accumulation. The total herbage mass decreased throughout the dry season. Crude protein and in vitro digestibility of organic matter of the leaf were higher in the upper 15 cm of the canopy stratum. The average daily weight gain of the animals supplemented with legume hay was similar to that gained by animals supplemented with soybean meal in the four grazing cycles. The total live weight gain of animals supplemented with legume hay was higher than the animals supplemented only with multiple mixing the first two grazing cycles. Hays of Leucena and Gliricidia can be given for supplementation of sheep maintained on pasture

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The flyingfish, Hirundichthys affinis (Günther, 1866) (Exocoetidae) and ballyhoo half beak, Hemiramphus brasiliensis (Linnaeus, 1758) (Hemiramphidae) are marine fish species of commercial value, which contribute to artisanal fishery production of Rio Grande do Norte, Brazil. Besides the economic importance, these fish are important from an ecological point of view, being components in pelagic food chain, where they are the preferred prey of larger predators of high commercial value. This study aimed to determine the reproductive strategies of H. affinis and H. brasiliensis and the fishery production of H. affinis in the northern coast of Rio Grande do Norte. The results are presented in the form of six cientific articles and a review paper. The first article presents the morphometric measurements and meristic counts which confirmed the taxonomic status, population structure in length-weight and the gonad development of H. affinis through macroscopic observations of the ovaries and testes. Females of this species were bigger and heavier than males. The second article describes the reproductive tactics, such as, sex ratio, length at first sexual maturity, histological aspects of gonads, fecundity and spawning season, that indicate the reproductive strategy of H. affinis. The third article shows annual changes in the fishery production of H. affinis in Caiçara do Norte, during the period of 1993 to 2010, emphasizing the relevance of this fish in total fishery production of Rio Grande do Norte, besides registering the fall in production in the years 2008 to 2010. The fourth article describes the population structure, with respect to the length and weight, the length-weight relationship, growth type and sex ratio of Hemiramphus brasiliensis. The fifth article describes the reproductive biology of H. brasiliensis, with details about sex ratio, length at first sexual maturity, fecundity, type of breeding and spawning season. The sixth article deals with the reproductive strategy of H. brasiliensis. The review paper presents the topic of age determination of tropical fish using analysis of otoliths. Both species use the coastal waters of Caiçara do Norte for reproductive purposes. The flying fish, H. affinis migrates from the oceanic waters to the coastal waters to reproduce, coinciding with the rainy season. H. affinis presents total spawning and a seasonal reproductive strategy. However, H. brasiliensis lives and reproduces in the coastal waters displaying partial spawning and an equilibrium reproductive strategy

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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De acordo com o Agrianual (2005), a produção citrícola brasileira é de 17,7 milhões de toneladas ano-1,ocupando aproximadamente 1 milhão de hectares no território brasileiro e, deste total, 810 mil hectares localizam-se no Estado de São Paulo. A maioria dos solos brasileiros, inclusive aqueles onde foram instalados os pomares cítricos, apresenta reação ácida. Esta é, sem dúvida, a principal condição desfavorável dos solos e um dos fatores limitantes da produção em solos tropicais. O presente trabalho teve por objetivo estudar o efeito de diferentes modos de aplicação de calcário e de micronutrientes e analisar, de forma comparativa, os custos destes tratamentos em um pomar de laranjeira. O experimento foi desenvolvido na Fazenda Morumbi, município de Estrela D'Oeste-SP, num Argissolo Vermelho-Amarelo. A variedade de laranjeira utilizada foi a 'Natal', enxertada em limão Cravo, com 6 anos de idade e espaçamento 5 x 8 m. O delineamento experimental foi em parcelas subdivididas, com 3 repetições, com 5 tratamentos principais (sem calcário; a necessidade total de calcário (NC) incorporado; NC sem incorporação; ¹/2 NC no primeiro ano + ¹/2 NC no segundo ano e ¹/3 NC no primeiro ano, + ¹/3 NC no segundo ano, + ¹/3 NC no terceiro ano) e dois tratamentos secundários [micronutrientes via solo (FTE-BR 12: 11,5 % de ZnO e B2O3; 1% CuO; 5,4% de Fe2O3; 5,5% de MnO2; 0,2% de MoO3) e micronutrientes via foliar (sulfato de zinco a 0,5% e ácido bórico a 0,08%)], distribuídos em blocos casualizados. Não houve efeito significativo dos modos de aplicação da calagem e de micronutrientes sobre as variáveis avaliadas (produção, sólidos solúveis totais, acidez total titulável). Para massa média do fruto, o efeito significativo aconteceu apenas no primeiro ano, com a calagem em dose única e sem incorporação, e micronutrientes via solo. Concluiu-se que não houve efeito significativo dos modos de aplicação do calcário e dos micronutrientes para produção e massa média dos frutos da laranjeira 'Natal', e a receita líquida foi positiva em todos os tratamentos, sendo que o tratamento 5 [¹/3 da necessidade total de calcário (NC) no 1º ano + ¹/3 da NC no 2º ano, + ¹/3 da NC no 3º ano] apresentou o melhor valor acumulado (U$ 3.721,85 ha-1).