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A new model, in terms of finite bipartite graphs, of the free pseudosemilattice is presented. This will then be used to obtain several results about the variety SPS of all strict pseudosemilattices: (i) an identity basis for SPS is found, (ii) SPS is shown to be inherently non-finitely based, (iii) SPS is shown to have no irredundant identity basis, and (iv) SPS is shown to have no covers and to be ∩-prime in the lattice of all varieties of pseudosemilattices. Some applications to e-varieties of locally inverse semigroups are also derived.

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Abstract  

In this study, bromine (Br), chlorine (Cl), potassium (K) and sodium (Na) were measured in the blood of Brazilian inhabitants from Southeast (S) and Northeast (N) regions. A reference range was established as a function of sex and considering lifestyle factors (non-smokers and non- drinkers). For both regions lower values of K were found in females when compared to males and lower values of Na were found in males compared to females. Increasing trends for Na and Br were observed in the Northeast region.

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Summary  

In general, when characterizing samples, such as ceramic samples or other types of samples, for first time by means of chemical elements, the analyst measures a large number of variables, many of which may not be very informative. In fact, some may even be unrelated to the issue at hand and blur the picture instead of making it clearer. In subsequent studies the analyst may wish to measure fewer variables for several reasons, such as being very time consuming; in cases where measurement time is important, such as on-line monitoring; in order to reduce cost or effort; etc. Therefore, the hope is to determine those variables that are most relevant without losing essential information and to remove the less productive information. The problem is how to perform this in an objective way and to capture crucial information using a multivariate analysis. This paper aims to describe and illustrate a stopping rule for the identification of redundant variables, and the selection of variable subsets, preserving multivariate data structure using stepwise discriminant analysis, selecting those variables that are in some senses adequate for discrimination purposes. One illustrative example using data sets obtained via INAA of ceramic samples from two archaeological sites is provided.

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Norfloxacin (NFX) is a synthetic antibacterial drug. The development of extended release tablets improves the patients’ comfort and compliance, resulting in lower discontinuation of the therapy; with consequently decrease in bacterial resistance. In the present work, the thermal behavior of NFX was investigated using TG and DSC techniques. Isothermal and non-isothermal methods were employed to determine kinetic data of decomposition process. Compatibility studies between NFX and pharmaceutical excipients, including three hydrophilic polymers were carried out in order to develop a new formulation of NFX to obtain extended release tablets with an approved quality.

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The interactive processes operating on the continental shelf adjacent to the river mouth control the amount and the characteristics of the Amazon discharge reaching the Atlantic Ocean. In this study, the distribution of trace elemental concentrations, with emphasis to the rare-earth elements, in sediment cores collected at several stations from the Amazon continental shelf during the falling water period was investigated by instrumental neutron activation analysis. Cores from the terrigenous and blue water zones have relatively uniform REE concentrations throughout the profile. Cerium anomalies for samples of the upper section of the eight stations are consistently positive and of high values (normally >2). Similar variation in the elemental concentration ratios between the seabed sediments and Amazon River suspended sediments was seen for stations located in the biogenic and blue water zones, with an enrichment for Ce, Sm, Fe, Th, and Sc and a depletion for the La, Eu, Tb, Yb, Co, Cr, Cs, Hf, Ta, and Zn. The shale-normalized REE patterns from shelf sediments are enriched in LREE relative to HREE, with enrichment factors varying from 1.5 for stations near the river mouth (terrigenous zone) to 1.9 for stations located far in the blue water zone. Published data for the Amazon River suspended sediment agree remarkably well with this observation of LREE-enrichment.

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One of the great 3D micro tomography (3D-mCT) applications in the medical area is the characterization of bone architecture, especially when it is spoken in osteoporosis because, among other factors, is characterized by the deterioration of the architecture. This work shows the 3D quantification, based on stereological concepts, of the bone tissue through 3D-mCT in real time. The analyses were carried out in femur rat and the 3D visualizations helped to understand bones morphology. The results showed the potential of this computational technique to verify the capability of characterization of the internal bone structures and the importance of the threshold level in the binarization process.

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Summary  

Neutron activation analysis, using Au as flux monitor, was applied to determine the concentrations of Br, Cl, K and Na in blood of healthy male and female blood donors, selected from blood banks and hematological laboratories from different regions of Brazil. The aims of this study were to collect more reference values of the Brazilian population as well as to perform hematological investigations. The advantages as well as the limitations of using this nuclear procedure are discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Iwahara, L. Tauhata, A. Oliveira, I. Nícoli, F. Alabarse, A. Xavier, M. Oliveira, M. Koskinas, and M. Almeida

Abstract  

Proficiency tests established by ISO/IEC-43 were applied to assess the performance of 69 Brazilian nuclear medicine services in the radiopharmaceuticals activity measurements of 131I, 99Tcm, 67Ga and 201Tl. The 214 datasets originated from comparison programs promoted by the Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI) in 2006/2007 were also evaluated against acceptance criteria of ±10% limits for accuracy required by Brazilian regulatory authority. The results of performance evaluation were assigned as “Acceptable” or “Not-acceptable” accordingly and have shown a large dispersion when the statistical criteria assays were applied and also compared with regulatory requirements.

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Abstract  

The concentrations of Cl, K and Na were analyzed in human body fluids (whole blood and serum) using NAA, resulting in the first biochemical baseline values for the Brazilian population. These data permitted us a discussion about the advantages and limitations of using this analytical technique for clinical chemistry.

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