Fronteiras DEA nebulosas para dados intervalares.

A fronteira DEA nebulosa surge em situações nas quais algumas variáveis (inputs ou outputs) apresentam um certo grau de incerteza na medição, sem que se assuma que os valores obedecem a alguma distribuição de probabilidade. A fronteira eficiente é construída considerando-se os limites de incerteza, isto é, os menores e maiores valores possíveis de serem assumidos pela variável afetada pela incerteza de medição. Dessa forma, constrói-se uma região em relação à qual as DMUs possuem um certo grau de pertinência. Para calcular o grau de pertinência são construídas fronteiras otimistas e pessimistas. Como o grau de pertinência não é uma medida de eficiência, é introduzido o conceito de fronteira invertida que permite calcular um índice de eficiência difuso. É mostrado o caso em que apenas uma variável apresenta incerteza e é generalizado para o caso em que algumas ou todas as variáveis apresentam incertezas

Implementation of different integrated crop-livestock systems in lowlands of Southern Brazil: an animal production approach.

The introduction of integrated crop-livestock systems (ICLS) is an alternative to rice monoculture in lowlands of Southern Brazil..

Emissão de gases de efeito-estufa em solos sob floresta e sob pastagem.

Considerando esses aspectos, este estudo teve por objetivo apresentar e discutir dados referentes ao tempo zero do monitoramento dos fluxos de N O dos solos sob pastagem e sob 2 remanescentes florestais na área do Comperj.bitstream/item/110397/1/Capitulo-XII-R8-170714.pd

Comparação entre Agregações Aritméticas e Geométricas de Índices de Pertinência a Fronteiras de Eficiência Difusas.

Neste trabalho estudam-se as conseqüências do uso de duas dessas medidas: a média aritmética e a média geométrica. A primeira tende a distribuir de forma mais uniforme as eficiências no intervalo [0,1], enquanto a segunda tende a ser mais extremada

Ionisation and dissociation of cometary gaseous organic molecules by solar wind particles I: Formic Acid

In order to simulate the effects of energetic charged particles present in the solar wind colliding with the cometary gaseous formic acid molecule (HCOOH), laboratory experiments have been performed. The absolute ionisation and dissociation cross sections for this molecule interacting with solar wind particles were measured employing fast electrons in the energy range of 0.5 to 2 keV and energetic protons with energies varying from 0.128 to 2 MeV. Despite the fact that both projectiles lead to a very similar fragmentation pattern, differences in the relative intensities of the fragments were observed. Formic acid survives about 4-5 times more to the proton beam than to the energetic electron collision.The minimum momentum transfer in the electron impact case was estimated to be 3-38% larger than the minimum momentum transfer observed with the equivelocity protons. The UV photodissociation rates and half-lives for HCOOH are roughly closer to the values obtained with energetic electrons. It is consequently important to take electron impact data into account when developing chemical models to simulate the interplanetary conditions.Comment: 11 pages, 7 figures, 5 tables, Accepted to be published in MNRA

Trypanosoma cruzi Epimastigotes Are Able to Store and Mobilize High Amounts of Cholesterol in Reservosome Lipid Inclusions

Reservosomes are lysosome-related organelles found in Trypanosoma cruzi epimastigotes. They represent the last step in epimastigote endocytic route, accumulating a set of proteins and enzymes related to protein digestion and lipid metabolism. The reservosome matrix contains planar membranes, vesicles and lipid inclusions. Some of the latter may assume rectangular or sword-shaped crystalloid forms surrounded by a phospholipid monolayer, resembling the cholesterol crystals in foam cells.Using Nile Red fluorimetry and fluorescence microscopy, as well as electron microscopy, we have established a direct correlation between serum concentration in culture medium and the presence of crystalloid lipid inclusions. Starting from a reservosome purified fraction, we have developed a fractionation protocol to isolate lipid inclusions. Gas-chromatography mass-spectrometry (GC-MS) analysis revealed that lipid inclusions are composed mainly by cholesterol and cholesterol esters. Moreover, when the parasites with crystalloid lipid-loaded reservosomes were maintained in serum free medium for 48 hours the inclusions disappeared almost completely, including the sword shaped ones.Taken together, our results suggest that epimastigote forms of T. cruzi store high amounts of neutral lipids from extracellular medium, mostly cholesterol or cholesterol esters inside reservosomes. Interestingly, the parasites are able to disassemble the reservosome cholesterol crystalloid inclusions when submitted to serum starvation

Selection of high-performance black-eyed cowpea (Vigna unguiculata) through GYT biplot analysis: a new methodology based on multiple characteristics.

Cowpea bean is a common crop quite appreciated in Brazil. However, it is known that its low yield depending on soil and climatic conditions. The aim of this research is the selection of high-performance black-eyed cowpea through GYT biplot analysis. Twelve (12) cowpea bean strains were assessed between 2016 and. The study followed a randomized complete block design, with four repetitions; two commercial cultivars were used ascheck. The following variables were assessed: number of days required for flowering, final stand, value for cultivation, pod yield, pod length, mean number of grains per pod and grain weight. The analysis of variance showed genetic variability between strains, differences between the assessed years and different strain-performance in each growing year. Based on the GYT biplot graph, cultivar BRS Itaim, and strains L9 and L7 recorded the best performance for the set of yield characteristics. Variable ?pod length? had positive correlation to bedding, number of days required for flowering and number of grains per pod. Variable ?100-grain weight? had positive correlation to final stand, pod yield and mean grain weight per pod. Strains L9, L7 and cultivar BRS Itaim recorded the best yield regarding the assessed variables