460 research outputs found
maigesPack: A Computational Environment for Microarray Data Analysis
Microarray technology is still an important way to assess gene expression in
molecular biology, mainly because it measures expression profiles for thousands
of genes simultaneously, what makes this technology a good option for some
studies focused on systems biology. One of its main problem is complexity of
experimental procedure, presenting several sources of variability, hindering
statistical modeling. So far, there is no standard protocol for generation and
evaluation of microarray data. To mitigate the analysis process this paper
presents an R package, named maigesPack, that helps with data organization.
Besides that, it makes data analysis process more robust, reliable and
reproducible. Also, maigesPack aggregates several data analysis procedures
reported in literature, for instance: cluster analysis, differential
expression, supervised classifiers, relevance networks and functional
classification of gene groups or gene networks
Fast multi-image matching via density-based clustering
We consider the problem of finding consistent matches
across multiple images. Previous state-of-the-art solutions
use constraints on cycles of matches together with convex
optimization, leading to computationally intensive iterative
algorithms. In this paper, we propose a clustering-based
formulation. We first rigorously show its equivalence with
the previous one, and then propose QuickMatch, a novel
algorithm that identifies multi-image matches from a density
function in feature space. We use the density to order the
points in a tree, and then extract the matches by breaking this
tree using feature distances and measures of distinctiveness.
Our algorithm outperforms previous state-of-the-art methods
(such as MatchALS) in accuracy, and it is significantly faster
(up to 62 times faster on some bechmarks), and can scale to
large datasets (with more than twenty thousands features).Accepted manuscriptSupporting documentatio
The quest for equity in Latin America: a comparative analysis of the health care reforms in Brazil and Colombia
<p>Abstract</p> <p>Introduction</p> <p>Brazil and Colombia have pursued extensive reforms of their health care systems in the last couple of decades. The purported goals of such reforms were to improve access, increase efficiency and reduce health inequities. Notwithstanding their common goals, each country sought a very different pathway to achieve them. While Brazil attempted to reestablish a greater level of State control through a public national health system, Colombia embraced market competition under an employer-based social insurance scheme. This work thus aims to shed some light onto why they pursued divergent strategies and what that has meant in terms of health outcomes.</p> <p>Methods</p> <p>A critical review of the literature concerning equity frameworks, as well as the health care reforms in Brazil and Colombia was conducted. Then, the shortfall inequality values of crude mortality rate, infant mortality rate, under-five mortality rate, and life expectancy for the period 1960-2005 were calculated for both countries. Subsequently, bivariate and multivariate linear regression analyses were performed and controlled for possibly confounding factors.</p> <p>Results</p> <p>When controlling for the underlying historical time trend, both countries appear to have experienced a deceleration of the pace of improvements in the years following the reforms, for all the variables analyzed. In the case of Colombia, some of the previous gains in under-five mortality rate and crude mortality rate were, in fact, reversed.</p> <p>Conclusions</p> <p>Neither reform seems to have had a decisive positive impact on the health outcomes analyzed for the defined time period of this research. This, in turn, may be a consequence of both internal characteristics of the respective reforms and external factors beyond the direct control of health reformers. Among the internal characteristics: underfunding, unbridled decentralization and inequitable access to care seem to have been the main constraints. Conversely, international economic adversities, high levels of rural and urban violence, along with entrenched income inequalities seem to have accounted for the highest burden among external factors.</p
WHY BRAZIL DOESN’T INNOVATE: A COMPARISON AMONG NATIONS
In this paper, we analyze the relevance of innovation concerning the emergence of important changes in the society. In order to verify which are the most relevant factors when it comes to the allocation of countries in an innovation ranking (Global Innovation Index), we accomplished a quantitative study, in which the procedure of multiple linear regression was used. The sample of our study comprised 33 countries and the analysis of the theoretical framework was carried out conducive to the creation of six independent variables. As result, the variables "GDP per capita”, “Public expenditures on R&D”, “Exports of high-tech goods”, “Public expenditures on education”, “Number of large companies” and “Number of patents” are in descending order the ones most related to the innovation level reached by some countries. The only variable negatively correlated to innovation is the number of patents registered in a determined country; in other words, one may conclude that patents are not the most relevant indicator linked with the development of innovation. We also emphasize the role played by the government when providing a favorable institutional environment in order to encourage and support innovation
Comparing the environmental impacts of ethyl biodiesel production from soybean oil and beef tallow through lca for brazilian conditions
The present paper sought compare the environmental impacts throughout the life cycle of biodiesel production obtained from the two raw materials most used in Brazil (soybean oil and beef tallow) through the process ethyl transesterification in an alkaline medium. The reference flow adopted for the work was the generation of power supplied 1GJ from the produced biodiesel. The data used in the inventory life cycle were calculated based on similar scientific papers. The method of assessment of environmental impacts chosen was the CML 2001 modified. Altogether, it were analyzed nine categories of environmental impacts for both processes (abiotic depletion (kg Sb eq), land use (m2a), global warming (kg CO2 eq), ozone layer depletion (kg CFC-11 eq), human toxicity (kg 1,4-DB eq), freshwater ecotoxicity (kg 1,4-DB eq), terrestrial ecotoxicity (kg 1,4-DB eq), acidification (kg SO2 eq) and eutrophication (kg PO43- eq)). The results of evaluation of environmental impacts show that the biodiesel production process from soybean oil presents major environmental damage in seven categories of analyzed impacts (destruction of abiotic resources, destruction of the ozone layer, human toxicity, freshwater ecotoxicity, terrestrial ecotoxicity, acidification and eutrophication). The production process of biodiesel from tallow presents major environmental damage in two categories of impacts analyzed (land use and global warming). However, the results show that the absolute values of environmental damage caused by impacts of the production process using beef tallow are much more aggressive
Análise Fatorial Confi rmatória e Invariância Temporal da Positive and Negative Affect Schedule (PANAS)
This paper analyzes the structure and the temporal invariance of the Portuguese version of the Positive and Negative Affect Schedule. Previous studies are not consensual whether PANAS measures two or three affect factors and whether such factors are independent or correlated. In order to fi ll in this gap, we compared the original PANAS, as an independent bi-dimensional structure, with several other alternative structures. Two hundred forty fi ve university students and professional trainees answered the questionnaire in two distinct moments with a two month interval. The model of PANAS with a structure of two independent factors, Positive Affect (PA) and Negative Affect (NA), as proposed by the authors of the scale, was tested. However, the best model consisted of two independent factors, PA and NA, with the cross-loading of the item “excited” between PA and NA, and specifi ed error correlations between the same categories of emotions. Another gap in the literature is the temporal invariance analysis of the PANAS. This paper assesses the temporal invariance of the scale, using the structural equation modeling analysis. Although it was used in its state form version, the PANAS scale showed temporal stability in a two month interval.O artigo analisa a estrutura e a invariância temporal da versão portuguesa da Positive and Negative Affect Schedule. A investigação científi ca anterior não é consensual acerca da estrutura da PANAS, se é constituída por dois ou três fatores e se esses fatores são independentes ou correlacionados. De forma a colmatar esta lacuna, procedemos à comparação da estrutura da PANAS como tendo duas dimensões independentes com várias outras estruturas alternativas. Duzentos e quarenta e cinco estudantes universitários e de cursos de formação profi ssional responderam ao questionário em dois momentos, com dois meses de intervalo. Foi testado o modelo da PANAS que representa uma estrutura de dois fatores independentes, Afeto Positivo (AP) e Afeto Negativo (AN), tal como defi nida pelos autores da escala. Contudo, o melhor modelo foi o que representa uma estrutura de dois fatores independentes, com a ponderação dupla do item “excitado” entre o AP e o AN e especifi cando correlações entre os erros dos itens que pertencem às mesmas categorias de emoções. Outra lacuna na investigação é a análise da invariância temporal da PANAS. Este artigo analisa a invariância temporal da escala, utilizando a análise de modelos de equações estruturais. Embora a escala tenha sido aplicada na sua versão afeto estado, a PANAS revelou invariância temporal num intervalo de dois meses
Seasonal variation of some limnological factors of lagoa do Guarana : a varzea lake of the High Rio Parana, state of Mato Grosso do Sul, Brazil
Le lac de Guarana présente de fortes variations saisonnières des conditions physico-chimiques du milieu. Celles-ci sont attribuées à deux causes principales : d'une part, le régime hydrologique du Parana qui provoque des modifications de niveau dans le lac et l'inondation de la varzea et, d'autre part, les pluies qui augmentent les apports de carbone organique (composés humiques) et des nutriments par les petits affluents tributaires. (Résumé d'auteur
Tribo Vernonieae Cass
A tribo Vernonieae possui uma distribuição pantropical, com grande parte das espécies concentradas no Brasil e África. Atualmente, são reconhecidas 21 subtribos, 126 gêneros e cerca de 1.300 espécies (KEELEY; ROBINSON 2009; ROBINSON, 2007)...Fil: Esteves, Roberto. Universidade do Estado de Rio do Janeiro; BrasilFil: Loeuille, Benoit. Universidade Federal de Pernambuco; BrasilFil: Nakajima, Jimi Naoki. Universidade Federal de Uberlândia; BrasilFil: Marques, Danilo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Soares, Polyana N.. Colégio Cenecista Dr. José Ferreira; BrasilFil: Esteves Gonçalves, Vânia. Universidade Federal do Rio de Janeiro; BrasilFil: Mendonça, Cláudia. Universidade Federal do Rio de Janeiro; BrasilFil: Dematteis, Massimiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin
The Role of Personality Traits, Attachment Style, and Satisfaction With Relationships in the Subjective Well-Being of Americans, Portuguese, and Mozambicans
Personality traits, attachment security, and satisfaction with relationships are each important predictors of subjective well-being (SWB). However, no studies have included these predictors together to analyze the unique contribution of each to SWB. Furthermore, most studies are empirically based in Western/industrialized societies, and few studies include African countries. This article addresses the unique contribution of extroversion, neuroticism, attachment security, and satisfaction with relationships to SWB across three samples of 1,574 university students: 497 from North Carolina (United States of America), 544 from Maputo (Mozambique), and 533 from Lisbon (Portugal). Structural equation modeling analysis showed that in the American sample, emotional stability was a more important predictor of global SWB than satisfaction with relationships. In the Mozambican sample, satisfaction with relationships was far more important as a predictor of SWB than emotional stability. In the Portuguese sample, emotional stability and satisfaction with relationships were equally important predictors of SWB. The main difference between the three samples was the contribution of satisfaction with relationships to SWB. Similarities between the three samples include the low or nonsignificant contributions of extroversion and attachment to SWB, above and beyond the contribution of satisfaction with relationships and neuroticism, suggesting they may be sharing variance in the prediction of SWB
Contribuição para o conhecimento da flora do Estado de Alagoas
Esta contribuição é o início de uma série de estudos multidisciplinares sobre a Flora do Estado de Alagoas, questionando problemas ecológicos, taxinômicos e fito-econômicos. Sessenta e nove espécies componentes de Matas Orientais (Atlânticas), Dunas e Restingas, são aqui consideradas. _________________________________________________________________________________ ABSTRACTA series of studies was undertaker in cooperation with the Department of Phytochemistry of Universidade Federal de Alagoas (Brazil). These studies deal with the flora of Estado de Alagoas an 69 species from the "matas Atlânticas" sand dunes and "restingas" are treated here. Ecological, taxonomic an phyto-economic problems are discussed
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