42 research outputs found
A PISCICULTURA NO BRASIL: UM ESTUDO SOBRE A PRODUÇÃO E COMERCIALIZAÇÃO DE “OREOCHROMIS NILOTICUS”
Este estudo investiga a viabilidade de Produção e Comercialização de Tilápia do Nilo por pequenos produtores Paranaenses. Atualmente a Tilápia do Nilo é uma das espécies mais popular do país, sendo cultivada em vinte e dois estados brasileiros. Neste trabalho discutem-se os principais aspectos da piscicultura no país, analisando o período de 1995 a 2003. A partir deste estudo foi possível averiguar nas propriedades estudadas que os baixos custos com manutenções e manejos facilitados não prejudicam as outras atividades da propriedade, permitindo que a criação de tilápia tenha uma boa perspectiva de expansão entre os produtores. O custo total de produção obtido na produção de tilápia foi em torno de R 3,50 a R 82.250,00 per year. The farmers can sell the kilo of fish with a value between 4.00. Revenue reached depends largely in the market price and quantity of fish marketed. It was found that the producer reaches a gross profit margin of over 37%. Such rates of return emphasize the creation of tilapia as a highly profitable business investment, as the producer gets the return on capital invested in approximately three years.cultivo de tilápias, custos de produção, “Oreochromis niloticus”, cultivation of tilapia, costs of production, Livestock Production/Industries, Marketing,
Handwork and Geometry in the Early Years: Curricular Movements (1890-2020)
Background: Research in the history of mathematics education makes it possible to identify the links between manual practices and the teaching of geometry in the early years since the insertion of the subject Handwork, at the end of the 19th century, to the present time. Objectives: Analyse the interconnections between manual practices and the teaching of geometry developed by the school culture of primary education in São Paulo, since the early Republic. Design: The curricular regulations of the state of São Paulo and the national guidelines – PCN and BNCC – and school manuals that circulated in each historical moment are mobilised together with the results of research already developed in the area. The documents were collated and analysed to produce an understandable and sustainable historical narrative, based on evidence and controls. Data collection and analysis: The study inventoried research results and analysed teaching programs in the State of São Paulo, national guidelines at the end of the 20th century, and school manuals from different periods. Setting and participants: The research sources are documentary, most of them available in the UFSC Digital Repository. Results: The documental examination indicated that manual practices actively participate in the school culture and cause changes, from time to time. Handwork change its status from a school subject to a geometry teaching methodology, intended for the early school years, which we observe to this day. Conclusions: This research concluded that the understanding of the historical perspective contributes to reflection on the current educational problems, on the debate about how to mobilise tools for geometry teaching, questioning the feasibility or not of handwork acting as an appropriate methodology for the first explorations of geometric properties
Long-term ecological research in southern Brazil grasslands: effects of grazing exclusion and deferred grazing on plant and arthropod communities
Grazing exclusion may lead to biodiversity loss and homogenization of naturally heterogeneous and species-rich grassland ecosystems, and these effects may cascade to higher trophic levels and ecosystem properties. Although grazing exclusion has been studied elsewhere, the consequences of alleviating the disturbance regime in grassland ecosystems remain unclear. In this paper, we present results of the first five years of an experiment in native grasslands of southern Brazil. Using a randomized block experimental design, we examined the effects of three grazing treatments on plant and arthropod communities: (i) deferred grazing (i.e., intermittent grazing), (ii) grazing exclusion and (iii) a control under traditional continuous grazing, which were applied to 70 x 70 m experimental plots, in six regionally distributed blocks. We evaluated plant community responses regarding taxonomic and functional diversity (life-forms) in separate spatial components: alpha (1 x 1 m subplots), beta, and gamma (70 x 70 m plots), as well as the cascading effects on arthropod high-taxa. By estimating effect sizes (treatments vs. control) by bootstrap resampling, both deferred grazing and grazing exclusion mostly increased vegetation height, plant biomass and standing dead biomass. The effect of grazing exclusion on plant taxonomic diversity was negative. Conversely, deferred grazing increased plant taxonomic diversity, but both treatments reduced plant functional diversity. Reduced grazing pressure in both treatments promoted the break of dominance by prostrate species, followed by fast homogenization of vegetation structure towards dominance of ligneous and erect species. These changes in the plant community led to increases in high-taxa richness and abundance of vegetation-dwelling arthropod groups under both treatments, but had no detectable effects on epigeic arthropods. Our results indicate that decision-making regarding the conservation of southern Brazil grasslands should include both intensive and alleviated levels of grazing management, but not complete grazing exclusion, to maximize conservation results when considering plant and arthropod communities
Uso de cinza de olaria e composto orgânico de macrófita aquática na recuperação de solos degradados
A intensificação da atividade humana para fins econômicos tem ocasionado impactos ambientais significativos, como a supressão vegetal e consequentemente o empobrecimento do solo. Nesse sentido, esta pesquisa objetivou avaliar o uso de cinza de olaria e composto orgânico de macrófita aquática na recuperação de solos degradados. Assim, o experimento foi conduzido com delineamento experimental em esquema fatorial 5x5, sendo cinco doses do composto de aguapé e cinco doses de cinza com três repetições, onde as doses de cinza corresponderam à 0, 1, 3, 5 e 10% do volume de cada vaso e às de composto de aguapé à 0, 5, 10, 20 e 30%. Após a mistura da composição solo, composto e cinza de cada tratamento, esta foi colocada em vasos, incubados 20 dias, em seguida realizado o transplantio das mudas de Jucá (Libidibia ferrea). Por ocasião da coleta, as mudas foram cortadas ao nível do solo, secas em estufa de circulação forçada de ar a 70°C até peso constante, pesadas, trituradas em moinho para obtenção da matéria seca da parte aérea (MSPA) e posteriormente foram mineralizadas por digestão nítrica. Nos extratos foram determinados os teores totais de Fe, Zn, Mn, Cu, Cd e Pb. Após a retirada das mudas, o solo de cada vaso foi seco ao ar, homogeneizado e quantificado os teores de Fe, Zn, Mn, Cu, Cd e Pb. A adição das doses de cinza e o composto contribuíram para o aumento do pH, que consequentemente influenciou na absorção dos metais pesados pelas mudas
Reporting an experience : recovering and recording residues of teaching laboratories of Chemical Institute of the Federal University of Rio Grande do Sul.
An experience aiming to promote a residue interchange and recovery between the teaching laboratories of the Chemistry Institute of this University is described. At the present, several residues interchange have already appeared as advantageous. To make the work easier, a software has been developed in order to keep a record of all the residues generated by the teaching laboratories. Standard labels have been developed for the residues in order to organize them. The software and the label design are described
Feedback Inhibition of Starch Degradation in Arabidopsis Leaves Mediated by Trehalose 6-Phosphate
Oxidative Stress and Modification of Renal Vascular Permeability Are Associated with Acute Kidney Injury during P. berghei ANKA Infection
Malaria associated-acute kidney injury (AKI) is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. However, the causes that lead to a framework of malaria-associated AKI are still poorly characterized. Some clinical studies speculate that oxidative stress products, a characteristic of Plasmodium infection, as well as proinflammatory response induced by the parasite are involved in its pathophysiology. Therefore, we aimed to investigate the development of malaria-associated AKI during infection by P. berghei ANKA, with special attention to the role played by the inflammatory response and the involvement of oxidative stress. For that, we took advantage of an experimental model of severe malaria that showed significant changes in the renal pathophysiology to investigate the role of malaria infection in the renal microvascular permeability and tissue injury. Therefore, BALB/c mice were infected with P. berghei ANKA. To assess renal function, creatinine, blood urea nitrogen, and ratio of proteinuria and creatininuria were evaluated. The products of oxidative stress, as well as cytokine profile were quantified in plasma and renal tissue. The change of renal microvascular permeability, tissue hypoxia and cellular apoptosis were also evaluated. Parasite infection resulted in renal dysfunction. Furthermore, we observed increased expression of adhesion molecule, proinflammatory cytokines and products of oxidative stress, associated with a decrease mRNA expression of HO-1 in kidney tissue of infected mice. The measurement of lipoprotein oxidizability also showed a significant increase in plasma of infected animals. Together, our findings support the idea that products of oxidative stress, as well as the immune response against the parasite are crucial to changes in kidney architecture and microvascular endothelial permeability of BALB/c mice infected with P. berghei ANKA.State of Sao Paulo Foundation for Research Support (FAPESP)State of Sao Paulo Foundation for Research Support (FAPESP) [07/07139-3, 10/52180-4, 12/02270-2]CAPESCAPESBrazilian Council of Scientific and Technologic Development (International Associated Laboratory of Renal Immunopathology, CNPq/Inserm)Brazilian Council of Scientific and Technologic Development (International Associated Laboratory of Renal Immunopathology, CNPq/Inserm)Complex Fluids INCT (FAPESP/CNPq)Complex Fluids INCT (FAPESP/CNPq
Malaria in humait a county, state of Amazonas, Brazil. XIX - evaluation of clindamycin for the treatment of patients with Plasmodium falciparum infection
Geographic range extension of Elachistocleis corumbaensis Piva, Caramaschi & Albuquerque, 2017 (Anura, Microhylidae) with new records in ecotonal zones in the state of Mato Grosso, Brazil
Elachistocleis corumbaensis was documented in 2017 in the central region of the Brazilian Pantanal and no other record of the species has since been reported. In this study, we report on the extension of the geographic range of E. corumbaensis based on 4 new records found in the riparian forests of the Paraguay River, in the state of Mato Grosso. Of these, 1 specimen was collected in a protected area in the Pantanal. We also report on the presence of this species in the ecotones between the Pantanal, Cerrado, and Amazonia, which suggests that E. corumbaensis is associated with seasonally flooded forests but more widely distributed in western Brazil than previously reported