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Pelotas, Brazil

Considering that several phenolic compounds found in blackberry are beneficial to human health because of its antioxidant action, this study was conducted in order to optimize its extraction process for analysis. Samples were subjected to different extraction process: solvent, soaking time, solvent mixtures and acidified solvents. There were no differences in the results for volume of solvent, maceration time, solvent mixtures and acidification for the content of phenolic compounds; however, among the tested solvents, acetone was more efficient for extraction of phenolic compounds. The antioxidant activity was not affected by maceration time and the solvent mixtures; however the volume, the type of solvent and its acidification affected the antioxidant activity. Source

Giasson E.,Federal University of Rio Grande do Sul | Sarmento E.C.,Federal University of Rio Grande do Sul | Weber E.,Federal University of Rio Grande do Sul | Flores C.A.,Embrapa Clima Temperado | Hasenack H.,Federal University of Rio Grande do Sul
Scientia Agricola | Year: 2011

When soil surveys are not available for land use planning activities, digital soil mapping techniques can be of assistance. Soil surveyors can process spatial information faster, to assist in the execution of traditional soil survey or predict the occurrence of soil classes across landscapes. Decision tree techniques were evaluated as tools for predicting the ocurrence of soil classes in basaltic steeplands in South Brazil. Several combinations of types of decicion tree algorithms and number of elements on terminal nodes of trees were compared using soil maps with both original and simplified legends. In general, decision tree analysis was useful for predicting occurrence of soil mapping units. Decision trees with fewer elements on terminal nodes yield higher accuracies, and legend simplification (aggregation) reduced the precision of predictions. Algorithm J48 had better performance than BF Tree, RepTree, Random Tree, and Simple Chart. Source

The present research had the objective of studying the influence of different spaces in-row (6×2 m, 6×3 m and 6×4 m) and propagation methods of 'Okinawa' rootstock (seeds and herbaceous cuttings) in variables related to 'Aurora-1' peach scion production. The trial was carried out at field conditions, in Vista Alegre do Alto, São Paulo State, Brazil, adopting the recommended technologies for peach culture. Evaluations were taken at the 2nd and 3rd years after planting. As conclusions, the propagation methods of 'Okinawa' rootstock did not influence the vegetative and productive characteristics of 'Aurora-1' scion, on both evaluated harvests. The 6×2 m space promotes significant improvements in 'Aurora-1' peach productivity. Source

Maytenus ilicifolia and M. aquifolium ("espinheira-santa") are medicinal species native to Brazil. They are endangered due to the strong anthropic action in natural populations. The aim of this work was to evaluate the genetic divergence in "espinheira-santa" germplasm and to cluster accessions by multivariate analyses based on morphophysiological traits of progenies. Eighty-nine accessions of the "espinheira-santa" active germplasm bank from the Brazilian Agricultural Research Corporation (EMBRAPA) Temperate Agriculture, Pelotas Federal University, Pelotas Municipality, Rio Grande do Sul State, Brazil, were evaluated regarding days from sowing to emergence; height and stem-base diameter at 90, 180, 270 and 360 days; height and stem-base diameter growth; leaf length and width; and number of thorns per leaf. Experimental design was in randomized blocks, with four replicates and five plants per plot. The results were subjected to analysis of variance and multivariate analysis of variance, and canonical variables were estimated. The evaluated traits were efficient for separating the accessions into three clusters. Height and stem-basal diameter at 360 days and leaf number at 180 days were the most important for "espinheira-santa" germplasm characterization. Source

Braga A.L.,Grande Rio University | Nakayama C.L.,Grande Rio University | Suita de Castro L.A.,Embrapa Clima Temperado | Wasielesky W.,Grande Rio University
Acta Zoologica | Year: 2013

The spermatozoa ultrastructure of the pink shrimp Farfantepenaeus paulensis was investigated in this morphological study. Spermatophores and spermatozoa were analyzed by electron microscopy. The pink shrimp spermatophore is divided into two regions: the appendage and the spermatophore main body, where spermatozoa are grouped in a spermatic mass. Pink shrimp spermatozoa are unistellate and are composed of main body and single spike. The spermatozoa body comprises a perinuclear cytoplasmic band, nucleus, acrosomal cap, and subacrosomal region. The spermatozoa cell mean total length was 10.71μm, the mean body diameter was 5.56μm, and the mean spike length and diameter were 5.15μm and 0.85μm, respectively. © 2011 The Authors. Acta Zoologica © 2011 The Royal Swedish Academy of Sciences. Source

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