Artigos científicos, teses e dissertações
Publicados nas melhores instituições de ensino

OBJECTIVE--To review the importance of heart rate variability analysis in left ventricular dysfunction and heart failure and to assess the effects of drug treatment. In patients with left ventricular dysfunction or heart failure, a low heart rate variability is a strong predictor...

2010...

In nanometer scale complementary metal-oxide-semiconductor (CMOS) parameter variations pose a challenge for the design of high yield integrated circuits. This work presents models that were developed to represent physical variations affecting Deep- Submicron (DSM) transistors and...

The relation between heart rate variability, measured from standard 24 hour electrocardiogram recordings in patients convalescent after a myocardial infarction, and the occurrence of sudden death and spontaneous, symptomatic, sustained ventricular tachycardia were assessed in a c...

ABSTRACT This study aimed to define management zones (MZs) for fertirrigated açaí cultivation, based on spatial variability of the foliar nutrients and productivity data. The work was carried out in an area of 5.75 ha of a 7-year crop, with 80 georeferenced sample points. Fresh f...

This dissertation describes a system for analysis of heart rate variability through metrics on time and frequency domain and by non-linear methodology, which is initiated by the process of segmentation of the QRS complex of the electrocardiogram signal. The motivation for this wo...

This study aimed to characterize the literature published in scientific journals regarding behavior analysis studies about behaviaral variability with human participants. From the analysis af the references of 26 canceptual and review texts, 42 experimental articles were read in ...

The aims of this study were to determine the power of discrimination of the real-time PCR assay for monitoring fluctuations in microbial populations within activated sludge and to identify sample processing points where methodological changes are needed to minimize the variabilit...

The amount of genetic variability on species can be influenced by factors acting in different levels of biological organization, and the ones related to population dynamics have been extensively studied. However, past studies neglected the influence of evolutionary history on gen...

The genetic improvement of aviary lines of breeding has contributed to the increasing efficiency of Brazilian poultry. Nevertheless, for the selection of superior genotypes in improvement programs, we must evaluate the existent variability, associated to the creation of birds in ...

Little consideration has been given to the effect of different segmentation methods on the variability of data derived from microarray images. Previous work has suggested that the significant source of variability from microarray image analysis is from estimation of local backgro...

MAZIN, S. C. Bayesian methods in meta-analysis: specication of prior distributions for the between-studies variability. 2009. 175s. Dissertation (master degree) - Faculty of Medicine of Ribeir~ao Preto, University of S~ao Paulo, Ribeir~ao Preto, 2009. Health professionals, resear...

The main point of this research proposes one methodology which analyses the variability of coarse CDW (Construction and Demolition Waste) recycled aggregates, applied on the quality control of these aggregates. With these analysis, it can be identified the influence of this varia...

A new image analysis technique is proposed for the evaluation of local anisotropy and its variability in stochastic texture images. It utilizes the gradient function to provide information on local anisotropy, from two-dimensional (2-D) density images for foil materials like poly...

The environment is constantly changing, so that variability is a feature of behavior of fundamental importance for the behavior of organisms. Selection only exists because the responses of an organism are never identical. The study of variability can contribute with the comprehen...

In deep-submicrometer technologies, process variability challenges the design of high yield integrated circuits. While device critical dimensions and threshold voltage shrink, leakage currents drastically increase, threatening the feasibility of reliable dynamic logic gates. Elec...

ABSTRACT Spatial variability evaluation of qualitative attributes can be used as an excellent strategy to design forms of intervention that result in better crop profitability for some agricultural crops, for example, sugarcane. Based on the assumption that qualitative attributes...

The causal agent of common bean anthracnose, Colletotrichum lindemuthianum, presents a wide genetic and pathogenic variability that has complicated the development of resistant cultivars. The aim of this study was to identify the variability within race 65 by RAPD markers and ana...

Nero Siciliano is an autochthonous pig breed that is reared mainly in semi-extensive systems in northeastern Sicily. Despite its economic importance and well-appreciated meat products, this breed is currently endangered. Consequently, an analysis of intra-breed variability is a f...

BACKGROUND--It has been shown that heart rate variability is decreased in patients with congestive heart failure and that depressed heart rate variability is associated with a propensity to ventricular arrhythmias. Little is known, however, about heart rate variability in patient...

Variability among 29 clinical and environmental strains of Legionella dumoffii was investigated by multilocus enzyme analysis by use of starch gel electrophoresis. Based on results of analysis at 20 enzyme loci, the strains were separated into five closely related electrophoretic...