Particle Learning for General Mixtures

This paper develops particle learning (PL) methods for the estimation of general mixture models. The approach is distinguished from alternative particle filtering methods in two major ways. First, each iteration begins by resampling particles according to posterior predictive probability, leading to a more efficient set for propagation. Second, each particle tracks only the "essential state vector" thus leading to reduced dimensional inference. In addition, we describe how the approach will apply to more general mixture models of current interest in the literature; it is hoped that this will inspire a greater number of researchers to adopt sequential Monte Carlo methods for fitting their sophisticated mixture based models. Finally, we show that PL leads to straight forward tools for marginal likelihood calculation and posterior cluster allocation.Business Administratio

A Statistical Approach for Multilingual Document Clustering and Topic Extraction from Clusters

2000 Mathematics Subject Classification: 62H30This paper describes a statistics-based methodology for document unsupervised clustering and cluster topics extraction. For this purpose, multiword lexical units (MWUs) of any length are automatically extracted from corpora using the LiPXtractor extractor - a language independent statistics-based tool. The MWUs are taken as base-features to describe documents. These features are transformed and a document similarity matrix is constructed. From this matrix, a reduced set of features is selected using an approach based on Principal Component Analysis. Then, using the Model Based Clustering Analysis software, it is possible to obtain the best number of clusters. Precision and Recall for document-cluster assignment range above 90%. Most important MWUs are extracted from each cluster and taken as document cluster topics. Results on new document classification will just be mentioned

Effect of plant spacing and bean cultivar on white mold and seed sanity

Parte da Tese de Doutorado do primeiro autor. Universidade de Brasília. 2001.Dois ensaios de campo foram realizados para avaliar o efeito do espaçamento entre linhas (30, 45 e 60 cm) e entre plantas de feijoeiro com hábitos de crescimento diferentes, sobre a intensidade do mofo- branco e a sanidade de sementes. No primeiro, foi mantida a mesma população de plantas por área, 27 plantas/m2 , reduzindo-se o espaçamento entre plantas. No segundo ensaio, manteve-se o mesmo espaçamento entre plantas, que resultou em populações de 40, 27 e 20 plantas/m2 . A porcentagem de plantas infectadas e a severidade da doença não diferiram estatisticamente quanto ao hábito de cresci- mento da cultivar, ao espaçamento ou à interação entre eles, mesmo a incidência tendo atingido valores de 98,4% em 1998 e de 2,7% em 1999. A porcentagem de sementes infectadas não foi afetada pelo espaçamento, mas diferiu erraticamente em relação às cultivares; em 1998, a cultivar Pérola não apresentou sementes infectadas, o mesmo acontecendo com a cultivar Diamante Negro em 1999.The effect of spacing among rows and among bean plants, as well as two plant growth habits were evaluated on the intensity of white mold and seed health in two field trials in Brasilia, DF, Brazil. In the first trial, the same population of 27 plants/m2 was maintained in rows of 30, 45 and 60 cm apart. In the second trial, the spacing among rows was maintained, which resulted in different plant populations of 40, 27 and 20 plants/m2, respectively. Disease incidence and severity did not differ statistically within plants of different growth habits or different spacing, even with divergent disease incidences of 98.4% and 2.7% observed in 1998 and 1999, respectively. The percentage of infected seeds was not affected by spacing either, however the cultivar effect was erratic; in 1998, 'Perola' had no infected seeds and the same occurred with 'Diamante Negro' in 1999

Characterization of Carbon Fibers Recovered by Pyrolysis of Cured Prepregs and Their Reuse in New Composites

The applications of composite materials are rapidly growing. In the aeronautical sector, composites account for up to 50% of the weight of a modern typical commercial aircraft. However, the amount of composites currently recycled is less than 5% of the total amount produced. With environmental concerns becoming an increasingly influential topic, recyclability of composite materials is a key issue. Furthermore, several related European laws have been passed to minimize the environmental impact of composite structures and to make rational use of landfills. In this chapter, the authors analyze recycling techniques for carbon fiber composites with thermoset polymer matrix. The objective is to reuse the fibers in new, lower cost composites with similar properties. Starting from a pyrolysis step, followed by oxidation, an evaluation of the different parameters of the recycling process has been performed. The characterization of the fibers includes tensile tests, scanning electron microscopy, and Raman spectroscopy. The recycled fibers presented a reduction of their initial tensile strength lower than 10%. Then, remanufacturing of laminates using the recycled fibers was achieved by resin film infusion, obtaining laminates with properties similar to the brand-new composites. These results have the potential to be exploited by the automotive, aeronautical, wind energy, construction, and other sectors

The Impact of Transcriptomics on the Fight against Tuberculosis: Focus on Biomarkers, BCG Vaccination, and Immunotherapy

In 1882 Robert Koch identified Mycobacterium tuberculosis as the causative agent of tuberculosis (TB), a disease as ancient as humanity. Although there has been more than 125 years of scientific effort aimed at understanding the disease, serious problems in TB persist that contribute to the estimated 1/3 of the world population infected with this pathogen. Nonetheless, during the first decade of the 21st century, there were new advances in the fight against TB. The development of high-throughput technologies is one of the major contributors to this advance, because it allows for a global vision of the biological phenomenon. This paper analyzes how transcriptomics are supporting the translation of basic research into therapies by resolving three key issues in the fight against TB: (a) the discovery of biomarkers, (b) the explanation of the variability of protection conferred by BCG vaccination, and (c) the development of new immunotherapeutic strategies to treat TB

C14. Um caso de polimiosite, fibrose pulmonar e cancro do pulmão

The authors present the case of a 67 year-old man with a 50-pack-year history of cigarette smoking. He had been in the navy for 30 years where he was exposed to asbestos fibbers.He had been asymptomatic until the age of 62, when he started to experience increasing exertional dyspnoea. One year later he had an episode of fever, productive cough and myalgias. Digital clubbing was noticed and bibasilar crackles were present on chest auscultation.Thoracic CT scan obtained at that time, were compatible with Usual Interstitial Pneumonia and bronchoalveolar lavage excluded other diseases. Pulmonary function studies: restriction and decreased DLco.Deflazacort, acetylcysteine and azathioprine were administered. Azathioprine was then switched to cyclophosphamide because of clinical and functional deterioration. Two years later he began Interferon Gamma 1b, with clinical and functional improvement lasting one year.He was then diagnosed Polymyositis and received Immunoglobulin.Twelve months later he was admitted to the hospital with intermittent fever, non productive cough, worsening exertional dyspnoea and myalgias. The Thoracic scan showed honeycombing and bronchiectasis. In the left inferior lobe there was a peripheral nodule. The patient was submitted to a Thansthoracic Needle Biopsy, the tissue immunocytochemistry pattern revealed Small Cell Lung Cancer. In the staging procedures there were positive mediastinal and hilar nodes and multiple hepatic metastases.Only one administration of chemotherapy was performed with carboplatinum and etoposide, without response. Unfortunately the patient died a fortnight later.Polymyositis has been associated with a variety of malignancies, in this case, the patient developed pulmonary fibrosis previously to the diagnosis of Polymyositis, and only several years later Small Cell Lung cancer was diagnosed

Using MACBETH with the choquet integral fundamentals to model interdependencies between elementary concerns in the context of risk management

Effective risk management typically requires the evaluation of multiple consequences of different sources of risk, and multicriteria value models have been used for that purpose. The value of mitigating a risk impact is often considered by risk managers as dependent on the levels of other impacts, therefore there is a need for procedures to identify and model these interactions within a value measurement framework. The Choquet Integral (CI) has been used for this purpose, and several studies in the performance measurement literature have combined the 2-additive CI operator with the MACBETH approach to model interdependencies in real contexts. In this paper, we propose an alternative procedure to model interdependencies and determine the CI parameters from one single MACBETH global matrix. The procedure is illustrated with the construction of a descriptor of impacts to evaluate the risk impacts at ALSTOM Power. The paper further explains the questioning protocol to apply the proposed procedure, as well as how decision-makers can interpret the CI parameters