Fission-track dating of Macusanite glasses with plateau and size correction methods

Two Macusanite pebbles (MB1 and MB2) were dated with the fission-track method. Six irradiations were carried out in different nuclear reactors: Pavia (Italy), IPEN-CNEN (Brazil) and IPEN-Lima (Peru). Measurements of the thorium and uranium induced-fission per target nucleus using natural thorium thin films and natural U-doped glasses calibrated against natural uranium thin films, together with lambda(F) of 8.46 x 10(-17) a(-1) were used to determine the ages. The apparent ages were corrected using the plateau and size correction methods. Track measurements were performed by different analysts, using different counting criteria. In addition, tracks were measured on samples which had been submitted to thermal treatment as well as on samples which had not been heated. Thermal treatments were carried out to erase the fossil tracks before neutron irradiation. No significant differences have been found in individual results, using the two Macusanite pebbles and the different nuclear reactors, age correction techniques, analysts, track-counting criteria, and thermal treatments before neutron irradiation. The great majority of the results (14/17) is compatible with the Ar-Ar ages of 5.12 +/- 0.11 and 5.10 +/- 0.11 Ma, Macusanite MB1 and MB2, respectively. However, the fission-track ages are systematically less (similar to8%) than the Ar-Ar ages of the two Macusanite samples studied. (C) 2003 Published by Elsevier Ltd.

A method for improving the code rate and error correction capability of a cyclic code

Currently, there has been an increasing demand for operational and trustworthy digital data transmission and storage systems. This demand has been augmented by the appearance of large-scale, high-speed data networks for the exchange, processing and storage of digital information in the different spheres. In this paper, we explore a way to achieve this goal. For given positive integers n,r, we establish that corresponding to a binary cyclic code C0[n,n-r], there is a binary cyclic code C[(n+1)3k-1,(n+1)3k-1-3kr], where k is a nonnegative integer, which plays a role in enhancing code rate and error correction capability. In the given scheme, the new code C is in fact responsible to carry data transmitted by C0. Consequently, a codeword of the code C0 can be encoded by the generator matrix of C and therefore this arrangement for transferring data offers a safe and swift mode. © 2013 SBMAC - Sociedade Brasileira de Matemática Aplicada e Computacional.

Convergence Property of the Measurement Gross Error Correction in Power System State Estimation, Using Geometrical Background

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Condição ocular dos indivíduos facectomizados na região centro-oeste do estado de São Paulo: estudo populacional

OBJETIVO: Avaliar as causas de baixa visão e cegueira em indivíduos facectomizados, de amostra da população de cidades da região centrooeste do estado de São Paulo. Métodos: Estudo transversal, observacional, feito em cinco cidades da região centro-oeste do estado de São Paulo, em amostra domiciliar e baseada nos dados do último Censo Demográfico (IBGE, 1995), com escolha sistemática dos domicílios. Foi considerada para o presente estudo uma subamostra de indivíduos facectomizados, dos quais foram obtidos dados de identificação e exame oftalmológico completo. Os dados foram avaliados por estatísticas descritivas, análise de freqüência de ocorrência e proporção de concordância, com intervalo de confiança de 95%. RESULTADOS: Dos indivíduos amostrados, 2,37% haviam sido submetidos à facectomia. Dos 201 olhos operados, 26,9% apresentavam acuidade visual compatível com cegueira ou deficiência visual. Com a melhor correção óptica, a acuidade visual permaneceu <0,3 em 19,0%. O exame refracional proporcionou melhora da acuidade visual para 27,9% dos indivíduos facectomizados. As causas de baixa visão foram os erros refrativos não corrigidos, opacidade de cápsula posterior (19,4%), ceratopatia bolhosa (8,3%) coriorretinite cicatricial (8,3%), afacia (8,3%), degeneração macular relacionada a idade (5,5%), leucoma (5,5%), glaucoma (5,5%), atrofia de papila (5,5,%), descolamento de retina (2,8%), atrofia de epitelio pigmentado da retina (2,8%) e alta miopia (2,8%). CONCLUSÃO: Apesar da catarata ser causa de cegueira que pode ser evitável, mesmo após a correção cirúrgica porcentagem expressiva de indivíduos permanece com baixa visão, em geral, em decorrência de fatores relacionados ao seguimento pós-operatório negligenciado.

Geração de VRS a partir de modelos atmosféricos: Conceito, implementação e resultados

Nowadays, with the implantation of GNSS (Global Navigation Satellite System) reference station networks, several positioning techniques have been developed and/or improved. Using such kind of network data it is possible to model the GNSS distance dependent errors and to compute correction terms for the network region. Several methods have been developed to formulate the corrections terms from network stations data. A method that has been received a great attention is the Virtual Reference Station (VRS). The idea is that the VRS data resemble as much as possible a real receiver data placed in the same local. Therefore, the user has the possibility of using the VRS as if it were a real reference station in your proximities, and to accomplish the relative positioning with a single frequency receiver. In this paper it is described a different methodology applied to implement the VRS concept, using atmospheric models developed by Brazilian researchers. Besides, experiments for evaluating the quality of generated VRS are presented, showing the efficiency of the proposed method.

A decoding procedure which improves code rate and error corrections

Corresponding to $C_{0}[n,n-r]$, a binary cyclic code generated by a primitive irreducible polynomial $p(X)\in \mathbb{F}_{2}[X]$ of degree $r=2b$, where $b\in \mathbb{Z}^{+}$, we can constitute a binary cyclic code $C[(n+1)^{3^{k}}-1,(n+1)^{3^{k}}-1-3^{k}r]$, which is generated by primitive irreducible generalized polynomial $p(X^{\frac{1}{3^{k}}})\in \mathbb{F}_{2}[X;\frac{1}{3^{k}}\mathbb{Z}_{0}]$ with degree $3^{k}r$, where $k\in \mathbb{Z}^{+}$. This new code $C$ improves the code rate and has error corrections capability higher than $C_{0}$. The purpose of this study is to establish a decoding procedure for $C_{0}$ by using $C$ in such a way that one can obtain an improved code rate and error-correcting capabilities for $C_{0}$.

Expert system for hot forging design

Planning hot forging processes is a time-consuming activity with high costs involved because of the trial-and-error iterative methods used to design dies and to choose equipment and process conditions. Some processes demand many months to produce forged parts with controlled shapes, dimensions and microstructure. This paper shows how expert systems can help engineers to reduce the time needed to design precision forged parts and dies from machined parts. The software ADHFD interfacing MS Visual Basic v.5.0 and SolidEdge v.3.0 was used to design flashless hot forged gears, chosen from families of gears. © 1998 Elsevier Science S.A. All rights reserved.

Avaliação da segurança e eficácia de novo preenchedor à base de ácido hialurônico no tratamento dos sulcos nasolabiais e contorno dos lábios

Introduction: The use of dermal filling techniques for soft tissue augmentation has greatly increased in recent years. Hyaluronic acid is one of the most used temporary dermal fillers in the treatment of facial wrinkles, furrows, and folds due to its effectiveness and safety. Objective: To evaluate the efficacy and safety of Perfectha®, a new hyaluronic acid filler, for nasolabial folds and lip correction. Methods: Open, multicenter study comprising 87 women. Efficacy was evaluated by the Global Aesthetic Improvement Scale and the Wrinkle Severity Rating Scale. Safety was evaluated through observation and the reporting of side effects. Results: One week after the injection of the filler, improvement in nasolabial folds and lips was observed in 86% and 89% of the women, respectively. Mild or moderate transient inflammatory reaction and ecchymoses occurred in 15% and 9% of patients, respectively, mainly in nasolabial folds. Two patients presented labial herpes simplex after treatment of the lips. The good results were maintained in 76% and 57% of women for nasolabial folds and in 72% and 45% of women for lips after 3 and 6 months, respectively. Conclusion: Perfectha® was effective and safe for these indications.

Crescimento econômico restrito pelo balanço de pagamentos, no Brasil: 1951-2008

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Modelagem e controle de sistemas fuzzy Takagi-Sugeno

Pós-graduação em Engenharia Elétrica - FEIS

Informação quântica e relatividade

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise da dinâmica de preços entre os mercados futuros de grão, farelo e óleo de soja na China e Estados Unidos

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Mercado de ações brasileiro: uma investigação empírica sobre suas relações de longo prazo e de precedência temporal pré-crise de 2008

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Next-generation sequencing reveals large connected networks of intra-host HCV variants

Background: Next-generation sequencing (NGS) allows for sampling numerous viral variants from infected patients. This provides a novel opportunity to represent and study the mutational landscape of Hepatitis C Virus (HCV) within a single host.Results: Intra-host variants of the HCV E1/E2 region were extensively sampled from 58 chronically infected patients. After NGS error correction, the average number of reads and variants obtained from each sample were 3202 and 464, respectively. The distance between each pair of variants was calculated and networks were created for each patient, where each node is a variant and two nodes are connected by a link if the nucleotide distance between them is 1. The work focused on large components having > 5% of all reads, which in average account for 93.7% of all reads found in a patient. The distance between any two variants calculated over the component correlated strongly with nucleotide distances (r = 0.9499; p = 0.0001), a better correlation than the one obtained with Neighbour-Joining trees (r = 0.7624; p = 0.0001). In each patient, components were well separated, with the average distance between (6.53%) being 10 times greater than within each component (0.68%). The ratio of nonsynonymous to synonymous changes was calculated and some patients (6.9%) showed a mixture of networks under strong negative and positive selection. All components were robust to in silico stochastic sampling; even after randomly removing 85% of all reads, the largest connected component in the new subsample still involved 82.4% of remaining nodes. In vitro sampling showed that 93.02% of components present in the original sample were also found in experimental replicas, with 81.6% of reads found in both. When syringe-sharing transmission events were simulated, 91.2% of all simulated transmission events seeded all components present in the source.Conclusions: Most intra-host variants are organized into distinct single-mutation components that are: well separated from each other, represent genetic distances between viral variants, robust to sampling, reproducible and likely seeded during transmission events. Facilitated by NGS, large components offer a novel evolutionary framework for genetic analysis of intra-host viral populations and understanding transmission, immune escape and drug resistance.

Balance-of-payments-constrained growth in Brazil: 1951-2008

The aim of this study is to determine whether Brazil's economic growth has been constrained by the balance of payments in the long run. The question underpinning the analysis can be expressed as follows: Was economic growth in the period 1951-2008 constrained by the balance of payments? To answer this question, the study employs the externally constrained growth methodology developed by Lima and Carvalho (2009), among others. The main statistical method used is vector error correction. The conclusion is that the rate of economic growth in Brazil was restricted by the external sector in the period concerned, validating the theory of balance-of-payments growth constraint with regard to the economic history of Brazil.