32 research outputs found
Efeito competência financeira em decisões de investimento: um estudo de caso à luz da Teoria do Prospecto
The Prospect Theory, by Kahneman and Tversky, points out that individuals have limitations in fully exercising their rationality in decision-making processes reacting differently to the same problem when it is presented in different ways. Thus using the Prospect Theory as a theoretical basis this article discussed and analyzed if it has some previous knowledge in finance can influence the formation of decision processes in investment situations. For this we replicate the empirical investigation of the seminal article by Kahneman and Tversky (1979) to two groups of students with distinct competences in finance and the results indicated, as in seminal research, that there are cognitive biases in the two groups, There is the presence of certainty effects, reflection and isolation, which oppose the hypotheses of the Expected Utility Theory.A Teoria do Prospecto, de Kahneman e Tversky, aponta que os indivíduos possuem limitações em exercer plenamente a sua racionalidade em processos decisórios reagindo de modo diferente a um mesmo problema quando este é apresentado de maneiras diferentes. Assim, utilizando a Teoria do Prospecto como fundamentação teórica, este artigo discutiu e analisou se possuir algum conhecimento prévio em finanças pode influenciar na formação dos processos decisórios em situações de investimento. Para isto replicamos a investigação empírica do artigo seminal de Kahneman e Tversky (1979) a dois grupos de estudantes com competências distintas em finanças e os resultados indicaram, da mesma forma que na pesquisa seminal, que há vieses cognitivos nos dois grupos, mais especificamente, há a presença dos efeitos certeza, reflexão e isolamento, que se opõem as hipóteses da Teoria da Utilidade Esperada
cDNA cloning and expression of Contractin A, a phospholipase A2-like protein from the globiferous pedicellariae of the venomous sea urchin Toxopneustes pileolus
Venomous sea urchins contain various biologically active proteins that are toxic to predators. Contractin A is one such protein contained within the globiferous pedicellariae of the venomous sea urchin Toxopneustes pileolus. This protein exhibits several biological activities, such as smooth muscle contraction and mitogenic activity. N-terminal amino acid residues of Contractin A have been determined up to 37 residues from the purified protein. In this study, we cloned cDNA for Contractin A by reverse transcription-PCR using degenerate primers designed on the basis of its N-terminal amino acid sequence. Analysis of the cDNA sequence indicated that Contractin A is composed of 166 amino acid residues including 31 residues of a putative signal sequence, and has homology to the sequence of phospholipase A2 from various organisms. In this study, recombinant Contractin A was expressed in Escherichia coli cells, and the protein was subjected to an assay to determine lipid-degrading activity using carboxyfluorescein-containing liposomes. As a result, Contractin A was found to exhibit Ca2+-dependent release of carboxyfluorescein from the liposomes, suggesting that Contractin A has phospholipase A2 activity, which may be closely associated with its biological activities
Nitric oxide orchestrates metabolic rewiring in M1 macrophages by targeting aconitase 2 and pyruvate dehydrogenase.
Profound metabolic changes are characteristic of macrophages during classical activation and have been implicated in this phenotype. Here we demonstrate that nitric oxide (NO) produced by murine macrophages is responsible for TCA cycle alterations and citrate accumulation associated with polarization. 13C tracing and mitochondrial respiration experiments map NO-mediated suppression of metabolism to mitochondrial aconitase (ACO2). Moreover, we find that inflammatory macrophages reroute pyruvate away from pyruvate dehydrogenase (PDH) in an NO-dependent and hypoxia-inducible factor 1α (Hif1α)-independent manner, thereby promoting glutamine-based anaplerosis. Ultimately, NO accumulation leads to suppression and loss of mitochondrial electron transport chain (ETC) complexes. Our data reveal that macrophages metabolic rewiring, in vitro and in vivo, is dependent on NO targeting specific pathways, resulting in reduced production of inflammatory mediators. Our findings require modification to current models of macrophage biology and demonstrate that reprogramming of metabolism should be considered a result rather than a mediator of inflammatory polarization
Rice panicle plasticity in Near Isogenic Lines carrying a QTL for larger panicle is genotype and environment dependent
Imaging the boundaries—innovative tools for microscopy of living cells and real-time imaging
Recently, light microscopy moved back into the spotlight, which is mainly due to the development of revolutionary technologies for imaging real-time events in living cells. It is truly fascinating to see enzymes “at work” and optically acquired images certainly help us to understand biological processes better than any abstract measurements. This review aims to point out elegant examples of recent cell-biological imaging applications that have been developed with a chemical approach. The discussed technologies include nanoscale fluorescence microscopy, imaging of model membranes, automated high-throughput microscopy control and analysis, and fluorescent probes with a special focus on visualizing enzyme activity, free radicals, and protein–protein interaction designed for use in living cells
Bioassays of water toxicity with sand biofilters\' effluent as an instrument of water quality evaluation
Biofiltros em Areia (BFAs) estão sendo aperfeiçoados e testados no Brasil com intuito de auxiliar comunidades carentes que são menos favorecidas em relação à água de boa qualidade. O presente estudo tem como objetivo analisar a qualidade da água tratada pelos BFAs a partir de bioensaios de toxicidade, utilizando larvas do inseto Chironomus sancticaroli, oligoqueto Allonais inaequalis e peixes da espécie Danio rerio, analisando possíveis efeitos tóxicos que possam estar presentes quando a água entra em contato com o PVC do corpo do BFA, além de avaliar a toxicidade da água do poço (AP), captada para abastecimento do BFA. Nos testes de toxicidade agudo (com duração de 96h), crônico (8 dias) e testes mais longos (16 dias) com Chironomus sancticaroli, utilizou-se 240mL da solução-teste (água proveniente do BFA ou AP) em 60g de sedimento controle (areia branca fina para aquário) em 4 réplicas, sendo utilizados 6 larvas de IV ínstar por réplica no teste de toxicidade agudo e de I ínstar nos testes de toxicidade crônico e testes mais longos, alimentadas com 5mL de solução contendo 1000mL de água deionizada e 5,0g de ração tipo Tetramim®. Nos testes de toxicidade agudo e crônico com Allonais inaequalis, foram utilizados 100mL da solução-teste em 5g de sedimento controle em quatro réplicas, sendo utilizados 6 organismos por réplica, alimentados com 5mL de solução contendo 1000mL de água deionizada e 2,0g de ração tipo Tetramim® , com duração de 96h e 10 dias, respectivamente. Foram realizados apenas testes de toxicidade agudo com D. rerio no qual utilizou-se 1000mL de solução-teste e 2 organismos por réplica, em duas réplicas, com duração de 48h, sem alimentação. Os resultados apontam para uma baixa toxicidade do Biofiltro em Areia em relação às três espécies testadas. Além de um índice alto de sobrevivência, a espécie C. sancticaroli concluiu seu ciclo em testes mais longos (16 dias), além de reproduzir-se; a espécie A. inaequalis apresentou 100% de sobrevivência em todos os testes realizados; e não houve mortalidade nos testes de toxicidade agudo com D. rerio. Porém, é importante destacar que estes resultados indicam apenas dados toxicológicos para fauna em relação as efluentes testados, não sendo possível responder a questões de potabilidade da água tratada pelo BFA. Esta dissertação é parte integrante de um projeto financiado pela FAPESP (Processo nº 2014/12712-8), intitulado \"Construção e desempenho de filtros lentos domiciliares conforme a realidade das comunidades isoladas do Brasil\" que esteve sob coordenação da Profa. Dra. Lyda Patricia Sabogal Paz e do Prof. Dr. Juliano José Corbi.Sand Biofilters (SBFs) are being refined and tested in Brazil. These studies are intended to assist needy communities with difficulties to access drinking water. The aim of the current study is analyze the quality of water treated by SBFs, using toxicity bioassays with larvae of fly Chironomus sancticaroli, oligochaete Allonais inaequalis and zebrafishes Danio rerio, as well as verify the occurrence of possible toxic effects of PVC (Polyvinyl chloride), a material component of SBFs\' structure, and also evaluate the toxicity of well water quality (AP), extracted to supply the SBF. In the acute toxicity tests (lasting 96h), chronic (lasting 8 days) and longer tests (lasting 16 days), all involving Chironomus sancticaroli, it was placed 240mL of sample solution (water from SBF or AP) in 60g of sterile sediment (fine white sand for aquarium) in four replicates, where was added 6 larvae (IV instar) in each replicate for the acute toxicity test, and larvae of I instar for chronic toxicity tests, even as in the longer tests. The organisms were fed by 5mL of Tetramim ® solution (5g/L). In the acute and chronic toxicity tests with Allonais inaequalis, it was applied 100mL of sample solution with 5g of sterile sand in four replicates, as above, it was added 6 organisms by replicate, fed by Tetramim ® (2,0g/L) for both tests, with lasting of 96h and 10 days, respectively. It was performed only tests of acute toxicity for D. rerio in which was added 1000mL of sample solution and 2 organisms for each replicate, with two replicates, with duration of 48h, without feeding. The results showed a low toxicity of sand Biofilters\' effluent in relation to the three species exposed to the liquid. Furthermore, the results demonstrate a high index of survival, even in longer tests (16 days lasting) with C. sancticaroli when the organisms could conclude their life cycle. However, besides the 100% of survival in all test, for the A. inaequalis were also observed reproduction; and in the acute toxicity tests for D. rerio it wasn\'t noticed mortality. Although, it is important to highlight that these results represent only toxicological data concerning to aquatic wildlife exposed to effluents, what is not regarding to potability issues of the water treated by SBF. This dissertation is a constituent part of a project financiad by FAPESP (Process number 2014/12712-8), entitled \"Building and performance of domiciliary slow filters according to the isolated comunities reality in Brazil\" which was coordinated by Professors PhD. Lyda Patricia Sabogal Paz and PhD. Juliano José Corbi
Effect financial competence in investment decisions: a case study in the light of the Prospectus Theory
A Teoria do Prospecto, de Kahneman e Tversky, aponta que os indivíduos possuem limitações em exercer plenamente a sua racionalidade em processos decisórios reagindo de modo diferente a um mesmo problema quando este é apresentado de maneiras diferentes. Assim, utilizando a Teoria do Prospecto como fundamentação teórica, este artigo discutiu e analisou se possuir algum conhecimento prévio em finanças pode influenciar na formação dos processos decisórios em situações de investimento. Para isto replicamos a investigação empírica do artigo seminal de Kahneman e Tversky (1979) a dois grupos de estudantes com competências distintas em finanças e os resultados indicaram, da mesma forma que na pesquisa seminal, que há vieses cognitivos nos dois grupos, mais especificamente, há a presença dos efeitos certeza, reflexão e isolamento, que se opõem as hipóteses da Teoria da Utilidade Esperada.The Prospect Theory, by Kahneman and Tversky, points out that individuals have limitations in fully exercising their rationality in decision-making processes reacting differently to the same problem when it is presented in different ways. Thus using the Prospect Theory as a theoretical basis this article discussed and analyzed if it has some previous knowledge in finance can influence the formation of decision processes in investment situations. For this we replicate the empirical investigation of the seminal article by Kahneman and Tversky (1979) to two groups of students with distinct competences in finance and the results indicated, as in seminal research, that there are cognitive biases in the two groups, There is the presence of certainty effects, reflection and isolation, which oppose the hypotheses of the Expected Utility Theory
Synthesis, Properties, and Crystal Structure of DDQ-Adducts of Ethynylated 2H-Cyclohepta[b]furan-2-ones
Ethynylated 2H-cyclohepta[b]furan-2-ones reacted with 2,3-dichrolo-5,6-dicyano-1,4-benzoquinone (DDQ) in a formal [2+2] cycloaddition reaction to afford the corresponding DDQ-adducts in good yields. The electronic properties of the DDQ-adducts were investigated by UV/Vis spectroscopy. One of the DDQ-adducts was revealed the molecular structure by X-ray crystallographic analysis. The redox behavior of the new compounds was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV).ArticleHETEROCYCLES. 88(1):319-329 (2014)journal articl