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Teresina, Brazil

Leite L.F.C.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuaria | Iwata B.F.,Instituto Federal do Piaui | Araujo A.S.F.,Federal University of Piaui
Revista Arvore | Year: 2014

This study aimed at quantifying total organic carbon stocks and its pools in Acrisol under agroforestry systems with six (AFS6) and thirteen years old (AFS13), slash-and-burn agriculture (SBA) and savanna native forest (SNF) in northeastern Brazil. Soil samples were collected at 0-0.05 m, 0.05-0.10 m, 0.10-0.20 m and 0.20-0.40 m depths in the dry and rainy seasons to evaluate total organic carbon (TOC) stocks and labile carbon (LC), fulvic acid fraction (C-FAF), humic acid fraction (C-HAF), humin (C-HF) and microbial biomass carbon (Cmic) contents. Additionally, carbon management index (CMI) was determined. Higher TOC stocks (97.7 and 81.8 Mg ha-1 for the 0-0.40 m depth in the dry and rainy seasons, respectively) and LC, humic substances and Cmic contents were observed in the AFS13 in all the depths. CMI also was higher in the AFS13 (0-0. 05 m: 158 and 86; 0.05-0.10 m: 171 and 67, respectively for the dry and rainy seasons) especially when compared to the SBA (0-0.05 m: 5.6 and 5.4; 0.05-0.10 m: 5.3 and 5.8, respectively for dry and rainy seasons). The agroforestry systems increased soil quality through the conservation of organic matter and can be considered an excellent strategy to assurance sustainability in tropical soil of Northeastern Brazil. © 2014, Sociedade de Investigacoes Florestais. All rights reserved. Source

Ju nior J.S.C.,Instituto Federal do Piaui | De Almeida A.A.C.,Federal University of Piaui | De Barros Falcao Ferraz A.,Lutheran University of Brazil | Rossatto R.R.,Lutheran University of Brazil | And 7 more authors.
Natural Product Research | Year: 2013

Garcinielliptone FC (GFC), a natural prenylated benzophenone, was extracted from Platonia insignis Mart. (Clusiaceae), a native plant commonly known as bacuri and used in traditional Brazilian medicine for the treatment of skin diseases. The aim of this study was to evaluate the cytotoxic and leishmanicidal effects of GFC using in vitro models. The experimental data demonstrated that the polyisoprenylated benzophenone GFC possesses cytotoxic and leishmanicidal activities. © 2013 Taylor & Francis. Source

Silva A.P.,Federal University of Piaui | Silva M.P.,Nucleo de Pesquisa em Doencas Negligenciadas | Oliveira C.G.,Nucleo de Pesquisa em Doencas Negligenciadas | Monteiro D.C.,Nucleo de Pesquisa em Doencas Negligenciadas | And 5 more authors.
Toxicology in Vitro | Year: 2015

Garcinielliptone FC (GFC) is a natural prenylated benzophenone found in the seeds of Platonia insignis Mart. (Clusiaceae), a native Brazilian plant. It has been chemically characterized and it is known that GFC has several biological activities such as antioxidant and vasorelaxant properties. In this study, we report the in vitro effect of GFC against the blood fluke Schistosoma mansoni, the parasite responsible for schistosomiasis mansoni. The anti-. S. mansoni activity and cytotoxicity toward mammalian cells were determined for the compound. GFC. ≥. 6.25. μM showed antischistosomal activity and confocal laser scanning microscopy analysis demonstrated several morphological alterations on the tegument of worms, and a correlation between viability and tegumental damage was observed. In addition, at sub-lethal concentrations of GFC (≤3.125. μM), the number of S. mansoni eggs was reduced. More importantly, GFC exhibited no activity toward mammalian cells and, therefore, there is an appreciable selectivity of this compound against the helminths. In conclusion, these findings indicate the potential of GFC as an antiparasitic agent. © 2014 Elsevier Ltd. Source

Camelo J.H.,Federal University of Piaui | Rabelo R.L.,Federal University of Piaui | Passos E.,Instituto Federal do Piaui
Brazilian Symposium on Games and Digital Entertainment, SBGAMES | Year: 2014

Role-Playing Games (RPG) are widely popular, and the idea of living in a parallel virtual world has attracted players for decades. Currently, as RPGs come in several flavors, such as tabletop RPG and eletronic media, one feature is paramount: character customization, in which the player has the ability to choose gameplay (and sometimes visual) character attributes. However, when a player decides his favorite values for gameplay attributes (such as strength or dexterity), the 3D character he sees has no correlation with these attributes. In this work, we propose a system that can automatically map from gameplay attributes to character aesthetics by using fuzzy system, which knowledge base is derived from players' knowledge. Besides detailing the technique, we present a complete user experiment that includes from rules definition to validation of results. © 2014 IEEE. Source

The Gaussian curve is a mathematical model for the distribution, i.e, it is an idealized description, which offers a concise picture of the overall pattern of data. In conducting an analysis is interesting to use graphics to explore data, to assess the relationships between variables, summarize findings and facilitate the interpretation of statistical results. From the data collected by weighing matchsticks presented a simple example for teaching normal distribution in the discipline of Statistics Applied Chemistry from the description of data and inferences, providing principles and methodologies that assist in the observation and participation by students in the teaching-learning process. The data collected is a good example of the normal distribution of data. © Universidad Nacional Autónoma de México. Source

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