999 resultados para biomassa inibição do crescimento


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The objective of this study was to examine the growth of Gracilaria cervicornis cultured in a shrimp (Litopenaeus vannamei) pond and to determine the absorption efficiency and the kinetics parameters (Vmax, Ks e Vmax:Ks) of this macroalgae for the nutrients N-NO3-, N-NH4+ and P-PO4-3, aiming at its use as bioremediatory of eutrophicated environments. For this study, two experiments (field and laboratory) were developed. In the field study, the seaweed was examined in relation to the growth and the biomass. In the laboratory experiment, the absorption efficiency of G. cervicornis was measured through the monitoring of the concentration of the three nutrients (N-NO3-, N-NH4+ e P-PO4-3) during 5 hours and the kinetic parameters were determined through the formula of Michaelis-Menten. The results obtained in this study demonstrated that G. cervicornis benefited from the available nutrients in the pond, increasing 52.4% of its biomass value after 30 days of culture. It was evidenced that the variability of the biomass could be explained through the salinity, availability of light (transparency and solid particle in suspension) and concentration of N-NO3- in the environment. In the laboratory experiment, the highest absorption efficiency was found in the treatments with low concentration (5 µmol.L-1), being evidenced a reduction of up to 85,3%, 97,5% and 81,2% of N-NH4+, N-NO3- and P-PO43-, respectively. Regarding the kinetic parameters, G. cervicornis presented better ability in absorbing N-NH4+ in high concentrations (Vmax = 158,5 µmol g-1 dry wt h-1) and P-PO43- in low concentrations (Ks = 5 µmol.L-1 e Vmax:Ks = 10,3). The results of this study show that G. cervicornis could be cultivated in shrimp ponds, presents a good capacity of absorption for the tested nutrients and is a promising candidate for biorremediation in shrimp pond effluent

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Linseed is an important oilseed consumed raw as nutritional supplement, that although represents a rich source of nutrients, its nutritional value could be impaired due to the presence of antinutritional factors. In this study, protein fractions from raw linseed flour were extracted and isolated being obtained 12% of albumins, 82% of globulins, 5% of glutelins and 1% of prolamins. These proteins were visualized by SDS-PAGE and albumins showed low molecular mass protein bands around 21 kDa and minor bands, similar to that of trypsin inhibitor; Globulins presented protein bands with high molecular masses, which possibly are constituents of multimeric proteins, such as legumins. After determination of the centesimal composition of raw linseed, it was used as exclusive protein source for young rats to evaluate its effect on animal growth. The results showed negative effects on rat growth (weight gain 73% less than the control group) and reduction of intestinal villus (35%), that could be related with in vitro and in vivo globulin digestibility and proteinaceous antinutritional factors (mammalian digestive enzymes inhibitors and lectins) in albumin fraction. Native globulins showed, by SDS-PAGE, low susceptibility in vitro to trypsin and chymotrypsin, however presented high degradation by pancreatin. Thermal treatment of globulins for 5 and 15 minutes at 100ºC improved considerably its digestibility by trypsin and pancreatin. Globulins presented 93.2% in vivo digestibility, similar to the control protein. Albumin fraction had high trypsin inhibition activity (100%) and chymotrypsin inhibition of 28.3%; haemagglutinating activity was not detected. The results of this study indicate the negative action of trypsin inhibitors on animal growth, but can not be discarded its combined action with other antinutritional factors, which could compromise the raw linseed utilization as an alternative food

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Sclerolobium panicudatum Vogel (taxi-branco-da-terra-firme) uma espécie nativa da Região Amazônica, de rápido crescimento, elevada produção de biomassa, capaz de associar-se com bactérias do gênero Rhizobium e com fungos micorrízicos. A madeira desta espécie possui características comparáveis àquelas tradicionalmente utilizadas no Sul do Brasil como fonte de energia. É de suma importância que sejam realizados estudos sobre as exigências nutricionais desta essência florestal tão promissora. Visando estudar o crescimento, foi desenvolvida a presente pesquisa, com o objetivo de avaliar os efeitos da aplicação do Fosfato natural trauíra superior na fase dc muda. O experimento foi instalado em casa de vegetação da Embrapa Amazônia Oriental, em vasos contendo Latossolo Amarelo álico. O delineamento experimental foi de blocos ao acaso, em esquema fatorial 4 x 5, sendo quatro doses: 0, 30, 60 e 90 ppm de fósforo (P); e cinco idades: 30. 60. 90. 120 c 150 dias. Foram avaliadas as variáveis: altura, número de folhas, área foliar, produção de matéria seca das folhas, caule, pane aérea, raiz e total. Constatou-se efeito significativo em todas as variáveis em função das idades, o número de folhas apresentou um ponto máximo de 9,59 folhas/planta, aos 110.62 dias. Quanto à aplicação das doses de fósforo, observou-se efeito significativo apenas nas variáveis área foliar, obtendo-se ponto máximo de 515.91 cm²/planta com aplicação da dose estimada de 52,86 ppm de P e na variável produção de matéria seca foliar com ponto máximo de 2,44 g/planta na dose estimada de 44,25 ppm de P.

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Este trabalho teve como objetivo estimar a quantidade de biomassa seca em plantios de Eucalyptus no estado de Minas Gerais, a partir de resultados de 244 parcelas de inventário florestal, considerando variações de qualidade do sítio, área basal e idade entre 2 e 8 anos. Foi estabelecida a classificação de sítio, com ajuste de equação utilizando os dados de idade e altura dominante. A biomassa total por hectare foi calculada multiplicando-se o volume por hectare pela densidade da madeira de Eucalyptus grandis e por um fator de expansão de biomassa. Avaliando-se a correlação entre biomassa total por hectare e variáveis ambientais e dendrométricas, verificou-se que a área basal e o índice de sítio foram as duas variáveis do povoamento de correlação mais alta, 0,93 e 0,64, respectivamente. Doze modelos foram ajustados para representar a quantidade de biomassa total por hectare tendo como variáveis independentes a área basal, o índice de sítio e a idade, bem como combinações entre estas. O modelo que apresentou melhor ajuste e precisão foi: Bs = exp[−6,7518 + 0,9567 × ln(G) + 0,0388 × ln?(G) + 4,0732 × ln(IS) − 0,4799 × ln?(IS)] × 1,0020, com R²ajustado de 0,955 e Syx% de 5,29%, e indicou valores de estoque de biomassa entre 39,7 e 174,9 Mg.ha-1, para área basal entre 8,9 e 27,9 m2.ha-1. A aplicação do modelo ajustado, com as variáveis índice de sitio e área basal por hectare, pode estimar de maneira prática e precisa a biomassa total por hectare, por utilizar variáveis de simples obtenção e por ter sido gerada a partir de um conjunto de dados com pouca variabilidade atribuída ao material genético.

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Objetivou-se determinar o efeito do alagamento do solo na produção de massa seca de 16 progênies de cupuaçuzeiro visando, posteriormente, incorporá-las no programa de melhoramento genético da espécie. O experimento foi instalado em casa de vegetação da Embrapa Amazônia Oriental, Belém-PA, no período de março a setembro de 2015. O delineamento experimental utilizado foi inteiramente casualizado, arranjados em esquema fatorial 16x2 com quatro repetições e uma planta por unidade amostral. Os tratamentos foram 16 progênies de cupuaçuzeiro e dois regimes hídricos (alagado e controle). Após 45 dias de aplicação do alagamento foi avaliada a produção de biomassa seca das plantas. No geral, o tratamento alagado proporcionou as maiores médias para todas as variáveis analisadas. Para as variáveis biomassa seca foliar (BF) e biomassa seca radicular (BR) as progênies que mais se destacaram foram a 46 e 57, já para a biomassa seca caulinar (BC), biomassa seca parte aérea (BPA) e biomassa seca total (BT) os materiais mais promissores foram 32, 46, 57 e 215. Por outro lado, a progênie 48 não obteve bom comportamento. Diferença significativa na razão biomassa seca radicular por biomassa seca da parte aérea (BR/BPA) foi observada para as progênies 47, 56 e 64. Pela avaliação global, as progênies 46 e 57 foram as mais tolerantes ao alagamento. Os materiais 47, 48 e 56 mostram ser menos favoráveis a esse estresse. O padrão de crescimento das progênies 46 e 57 sugere boa plasticidade fenotípica, o que indica boa potencialidade para seleção.

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Quimica Nova and the Journal of the Brazilian Chemical Society are two examples of successful initiatives taken by the Brazilian Chemical Society (SBQ - Sociedade Brasileira de Química), and may serve as models for the scientific societies of developing countries. Pillars of the SBQ, these two periodicals are undeniable demonstrations that idealism, utopia and dignity are the essential ingredients for transforming dreams into reality. Few believed that the Brazilian chemical community would one day have, as it does today, two scientific research periodicals indexed in the principal international data banks.

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The durability of the cellulose-cement composites is a decisive factor to introduce such material in the market. Polymers have been used in concrete and mortar production to increase its durability. The goal of this work was the physical and mechanical characterization of cellulose-cement composites modified by a polymer and the subsequent durability evaluation. The work also evaluated the dispersion of acrylic polymer in composites made of Pinus caribaea residues. The physical properties observed were water absorption by immersion and bulk density. Rupture modulus and toughness were determined by flexural test. The specimens were obtained from pads, produced by pressing and wet curing. Samples were subjected to accelerated aging tests by repeated wetting and drying cycles and hot-water bath and natural aging. The scanning electron microscopy (SEM) allowed verifying the fiber and composite characteristics along the time. For the composite range analyzed, it was observed the polymer improved the mechanical properties of composites besides a significant decreasing in water absorption. The use of polymer improved the performance of vegetable fiber-cement composites when compared to the conventional mortar, due to water absorption decreasing.

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The objective of this study was to analyze changes in the spectral behavior of the soybean crop through spectral profiles of the vegetation indexes NDVI and GVI, expressed by different physical values such as apparent bi-directional reflectance factor (BRF), surface BRF, and normalized BRF derived from images of the Landsat 5/TM. A soybean area located in Cascavel, Paraná, was monitored by using five images of Landsat 5/TM during the 2004/2005 harvesting season. The images were submitted to radiometric transformation, atmospheric correction and normalization, determining physical values of apparent BRF, surface BRF and normalized BRF. NDVI and GVI images were generated in order to distinguish the soybean biomass spectral response. The treatments showed different results for apparent, surface and normalized BRF. Through the profiles of average NDVI and GVI, it was possible to monitor the entire soybean cycle, characterizing its development. It was also observed that the data from normalized BRF negatively affected the spectral curve of soybean crop, mainly, during the phase of vegetative growth, in the 12-9-2004 image.

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Soil waterlogging and the subsequent reduction in the amount of oxygen available for the respiration of the root system selected, along the evolutive process, plants able to thrive in seasonally or permanently flooded areas. In neotropical plants there are many types of adaptations to flooding. In this paper we present the results of the work carried out with seeds and seedlings of C brasiliense subjected to hypoxia during germination and early development. C brasiliense seeds are not photoblastic and survive up to three months burried in a water saturated substrate, but germination only takes place in well-drained soils. Soil waterlogging does not inhibit seedling growth and there are no apparent morphological changes of the aerial part of flooded plants. New and aerated roots that make plant survival possible replace old and spoiled roots. In contrast to many typical species of flood-prone areas where growth is inhibited by oxygen stress. C. brasiliense seedlings seem to be well adapted to their waterlogged environment. Seed dispersion, the absence of photoblastic response as well as seed and seedling capacity of surviving and growing in waterlogged soils contribute to the wide geographic distribution of C. brasiliense always associated with areas subjected to soil waterlogging.

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The objective of the work was to evaluate the effects of environment, recipients, and substrate compositions in passion fruit (Passiflora edulis Sims f. flavicarpa Deg.) seedlings biomass production in Pantanal region from September to November of 2006. Experimental trials were conducted in four protected environments, in two types of containers and three different substrate compositions. The environments were: A1 (greenhouse covered with low-density, 150-microns-thick polyethylene film), A2 (monofilament black screened with mesh for 50% of shade), A3 (aluminized screened with mesh for 50% of shade) and A4 (environment covered with straw of native coconut palm); the recipients were: polyethylene bags (R1) (15 x 25 cm) and polystyrene trays (R2) (with 72 cells). There substrates were: S1 (soil + organic compost + vermiculite, 1:1: 1 v/v), S2 (soil + organic compost + sawdust, 1:1: 1 v/v) and S3 (soil + organic compost + vermiculite + sawdust, 1:1: 1/2: 1/2 v/v). The experimental design was completely randomized statistical analysis in split-split-plot, with fifteen replications. The treatments in the plot were environments, in the subplots were pots, and subsubplots were substrates (4 x 2 x 3 = 24 treatments). Fresh and dry mass of aerial and root system parts were evaluated. Environments with screen showed better results for seedlings of yellow passion fruit biomass in polyethylene bags. Polyethylene bags promoted higher biomasses. The substrate with vermiculite showed better results for both types of containers. The substrate with a higher percentage of sawdust showed the worst result.

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Ethanolic extracts from propolis were performed by using lhe water and vaflous coneentrations of etanol as solvent. The extracts were investigated by measurement of absorption spectruin with Uv-spectrophotometer (UV-scanning), reversed phase-high performance thin-layer chromatography, Reversed phase-HPLC. Maximum absorption of ali extracts was 290 nm, resembling flavonoid compounds and 80% ethanolic extract showed highest absorption at 290 nm. The most isosakuranetin, quercefin, and kaempferol were extracted from mixtures of propolis and 60% etanol, whereas 70% etanol extracted te most pinocembrin and sakuranetin, but 80% etanol extracted more kaempferide, acacetin, and isorhamnetin from propolis. The 60 to 80% ethanolic extracts ofpropolis inhibited highly to microbial growth and 70 and 80% ethanolic extracts showed lhe greatest antioxidant activity and 80% ethanolic extract inhibited highly to hyaluronidase activity.

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The recombinant human growth hormone (rhGH) can improve weight gain, physical growth, clinical and lung in cystic fibrosis (CF). However, the routine use, although promising, is not established in the literature. The objective of this study was to assess the benefits of rhGH in children and adolescents with CF. We conducted a systematic review in the database PubMed, Lilacs, SciELO and Cochrane, in the period 2000-2010, using the keywords: cystic fibrosis, growth hormone, children and adolescents. We found 77 articles and included 11 randomized controlled trials, with 290 children and adolescents with CF. The short-term use (1-24 months) of rhGH improved the height, weight, growth rate, bone mineral content and components of pulmonary function. Adverse effects, like diabetes, were not observed in the studies. The short-term use of rhGH improved growth and body composition in patients with CF.

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OBJECTIVE: To evaluate the growth and body composition of children and adolescents with type 1 diabetes mellitus (T1DM). SUBJECTS AND METHODS: A cohort of 44 patients with T1DM were followed up for approximately four years and compared with a control group. Weight, height, body mass index (BMI), body fat percentage (BF%), fat mass index, waist circumference (WC) and waist-height ratio were determined. RESULTS: In females, in the first evaluation, BF% was lower in patients than in controls, while in the second evaluation, mean WC was higher in patients than in controls. In males, height of the patients was lower in the first evaluation, while body mass index (BMI) was higher in the second one. We did not find any differences among the changes in height, weight and BMI z-scores and BF% or in the distribution of those z-scores between the two evaluations, in both groups. Multiple regression analysis found differences in BMI and waist-height ratio in both sexes and also in WC in females. CONCLUSION: The patients had adequate growth but showed discrepancy in their body composition during the study.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física