54 resultados para Topology-based methods
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Pós-graduação em Ciências Biológicas (Genética) - IBB
Resumo:
Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Agronomia - FEIS
Resumo:
This paper applies a genetic algorithm with hierarchically structured population to solve unconstrained optimization problems. The population has individuals distributed in several overlapping clusters, each one with a leader and a variable number of support individuals. The hierarchy establishes that leaders must be fitter than its supporters with the topological organization of the clusters following a tree. Computational tests evaluate different population structures, population sizes and crossover operators for better algorithm performance. A set of known benchmark test problems is solved and the results found are compared with those obtained from other methods described in the literature, namely, two genetic algorithms, a simulated annealing, a differential evolution and a particle swarm optimization. The results indicate that the method employed is capable of achieving better performance than the previous approaches in regard as the two criteria usually employed for comparisons: the number of function evaluations and rate of success. The method also has a superior performance if the number of problems solved is taken into account. (C) 2013 Elsevier B.V. All rights reserved.
Resumo:
Background: Immunity plays an important role in controlling human papillomavirus (HPV) infection and associated lesions. Unlike infections caused by other viruses, natural HPV infection does not always result in a protective antibody response. Therefore, HPV antibodies are also considered markers of cumulative exposure. The aim of this study was to identify determinants of HPV16 seroreactivity at enrollment among women from the Ludwig-McGill cohort, a natural history study of HPV infection and risk of cervical neoplasia.Methods: HPV16 serology was assessed by ELISA for L1 and L2 capsid antigens, while HPV typing and viral load measurements were performed by PCR-based methods. The associations were analyzed by unconditional logistic regression.Results: Of 2049 subjects, 425 (20.7%) were strongly seropositive for HPV16. In multivariate analysis, seroreactivity was positively correlated with age, lifetime number of sexual partners, frequency of sex, and HPV16 viral load, and negatively associated with duration of smoking.Conclusions: HPV16 seroreactivity is determined by factors that reflect viral exposure.
Resumo:
The food industry has been rapidly modernized, and with this the disposal and the consumption of industrialized food has been increasing continually. These products lose their original morphological characteristics, requiring fast and reliable tests that could help to identify the species in question, as most fraudulent behavior in the milk and dairy industry (meat and fish) is carried out where there is partial or total exchange of the original material for other with less value at market. Nowadays there is a lot of techniques that can be used for the identification of animal species, based on muscle protein, or DNA analysis. In the case of protein based analysis, we can mention several types of electrophoresis and immunologic methods, as ELISA. In the case of DNA based methods, we have several assays that use the amplification of DNA fragments, known as PCR, as proof. All these techniques have advantages and disadvantages that can be affected by factors- the sample condition, or the degree of relation between the species in question. Because of this, it’s necessary that a continuous study looking for the improvement of the available techniques, making sure that the confirmation of food authenticity is in place. This is to ensure the true product value, to comply with labeling regulationand and protect the consumer of frauds
Resumo:
The use of physical characteristics for human identification is known as biometrics. Among the many biometrics traits available, the fingerprint is the most widely used. The fingerprint identification is based on the impression patterns, as the pattern of ridges and minutiae, characteristics of first and second levels respectively. The current identification systems use these two levels of fingerprint features due to the low cost of the sensors. However, the recent advances in sensor technology, became possible to use third level features present within the ridges, such as the perspiration pores. Recent studies show that the use of third-level features can increase security and fraud protection in biometric systems, since they are difficult to reproduce. In addition, recent researches have also focused on multibiometrics recognition due to its many advantages. The goal of this research project was to apply fusion techniques for fingerprint recognition in order to combine minutia, ridges and pore-based methods and, thus, provide more robust biometrics recognition systems, and also to develop an automated fingerprint identification system using these three methods of recognition. We evaluated isotropic-based and adaptive-based automatic pore extraction methods, and the fusion of pore-based method with the identification methods based on minutiae and ridges. The experiments were performed on the public database PolyUHRF and showed a reduction of approximately 16% in the EER compared to the best results obtained by the methods individually
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Transposable elements (TEs) are widespread in insect´s genomes. However, there are wide differences in the proportion of the total DNA content occupied by these repetitive sequences in different species. We have analyzed the TEs present in R. prolixus (vector of the Chagas disease) and showed that 3.0% of this genome is occupied by Class II TEs, belonging mainly to the Tc1-mariner superfamily (1.65%) and MITEs (1.84%). Interestingly, most of this genomic content is due to the expansion of two subfamilies belonging to: irritans himar, a well characterized subfamily of mariners, and prolixus1, one of the two novel subfamilies here described. The high amount of sequences in these subfamilies suggests that bursts of transposition occurred during the life cycle of this family. In an attempt to characterize these elements, we performed an in silico analysis of the sequences corresponding to the DDD/E domain of the transposase gene. We performed an evolutionary analysis including network and Bayesian coalescent-based methods in order to infer the dynamics of the amplification, as well as to estimate the time of the bursts identified in these subfamilies. Given our data, we hypothesized that the TE expansions occurred around the time of speciation of R. prolixus around 1.4 mya. This suggestion lays on the Transposon Model of TE evolution, in which the members of a TE population that are replicative active are present at multiple loci in the genome, but their replicative potential varies, and of the Life Cycle Model that states that when present-day TEs have been involved in amplification bursts, they share an ancestral copy that dates back to this initial amplification.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)