Modeling water movement in horizontal columns using fractal theory

Fractal mathematics has been used to characterize water and solute transport in porous media and also to characterize and simulate porous media properties. The objective of this study was to evaluate the correlation between the soil infiltration parameters sorptivity (S) and time exponent (n) and the parameters dimension (D) and the Hurst exponent (H). For this purpose, ten horizontal columns with pure (either clay or loam) and heterogeneous porous media (clay and loam distributed in layers in the column) were simulated following the distribution of a deterministic Cantor Bar with fractal dimension H" 0.63. Horizontal water infiltration experiments were then simulated using Hydrus 2D software. The sorptivity (S) and time exponent (n) parameters of the Philip equation were estimated for each simulation, using the nonlinear regression procedure of the statistical software package SAS®. Sorptivity increased in the columns with the loam content, which was attributed to the relation of S with the capillary radius. The time exponent estimated by nonlinear regression was found to be less than the traditional value of 0.5. The fractal dimension estimated from the Hurst exponent was 17.5 % lower than the fractal dimension of the Cantor Bar used to generate the columns.

Temperature measurements by oh lif and chemiluminescence kinetic modeling for ethanol flames

OH LIF-thermometry was applied to premixed ethanol flames at atmospheric pressure in a burner for three flame conditions. Flame temperatures were simulated from energy equation with PREMIX code of CHEMKIN software package for comparison. A kinetic modeling based on a model validated through chemiluminescence measurements and on a set of reactions for nitrogen chemistry was evaluated. Marinov's mechanism was also tested. Sensitivity analysis was performed for fuel-rich flame condition with Φ = 1.34. Simulated temperatures from both reaction mechanisms evaluated were higher than experimental values. However, the proposed kinetic modeling resulted in temperature profiles qualitatively very close to the experimental.

Estudio teórico de la isomerización del ácido maleico en ácido fumárico: un enfoque basado en el concepto de superficie de energía potencial

A comparative study based on potential energy surfaces (PES) of 2-butanedioic and hypothetic 2-butanedioic/HCl acids is useful for understanding the maleic acid isomerization. The PES enables locating conformers of minimum energy, intermediates of reactions and transition states. From contour diagrams, a set of possible reaction paths are depicted interconnecting the proposed structures. The study was carried out in absentia and in the presence of the catalyst (HCl), using an solvatation model provided by the Gaussian software package. Clearly, the effect of HCl is given by new reaction paths with lower energetic barriers in relation to the reaction without catalyzing.

Data mining techniques for identification of spectrally homogeneous areas using NDVI temporal profiles of soybean crop

The aim of this study was to group temporal profiles of 10-day composites NDVI product by similarity, which was obtained by the SPOT Vegetation sensor, for municipalities with high soybean production in the state of Paraná, Brazil, in the 2005/2006 cropping season. Data mining is a valuable tool that allows extracting knowledge from a database, identifying valid, new, potentially useful and understandable patterns. Therefore, it was used the methods for clusters generation by means of the algorithms K-Means, MAXVER and DBSCAN, implemented in the WEKA software package. Clusters were created based on the average temporal profiles of NDVI of the 277 municipalities with high soybean production in the state and the best results were found with the K-Means algorithm, grouping the municipalities into six clusters, considering the period from the beginning of October until the end of March, which is equivalent to the crop vegetative cycle. Half of the generated clusters presented spectro-temporal pattern, a characteristic of soybeans and were mostly under the soybean belt in the state of Paraná, which shows good results that were obtained with the proposed methodology as for identification of homogeneous areas. These results will be useful for the creation of regional soybean "masks" to estimate the planted area for this crop.

Partial characterization and inactivation of peroxidases and polyphenol-oxidases of umbu-cajá (Spondias spp.)

A crude extract of Spondias spp. was evaluated for the influence of pH and temperature on the activity and stability of its peroxidases and polyphenol-oxidases. In order to evaluate the conditions for the inactivation of the enzymes by heat treatment and by addition of a reducing agent, a factorial experimental design (n = 3) was employed using the Statistica (6.0) software package for data analysis. The optimal conditions found for peroxidases were: pH = 5.0 and temperature = 40 ºC, and for polyphenol-oxidases they were pH = 7.0 and temperature = 40 ºC. The peroxidases and polyphenol-oxidases were stable at all pH values tested (3.0 - 10.0) and maintained more than 60% of their activity at temperatures above 30 and 40 ºC, respectively. To achieve the total inactivation of these enzymes, two alternatives can be suggested: incubation at 92 ºC for 3.15 minutes with 200 mg.L-1 of ascorbic acid or incubation at 96 ºC for 2.80 minutes with 100 mg.L-1 of ascorbic acid.

The Brazilian electronic theses and dissertations digital library: providing open access for scholarly information

This paper describes a project led by the Instituto Brasileiro de Informações em Ciência e Tecnologia (Ibict), a government institution, to build a national digital library for electronic theses and dissertations - Bibliteca Digital de Teses e Dissertações (BDTD). The project has been a collaborative effort among Ibict, universities and other research centers in Brazil. The developers adopted a system architecture based on the Open Archives Initiative (OAI) in which universities and research centers act as data providers and Ibict as a service provider. A Brazilian metadata standard for electronic theses and dissertations was developed for the digital library. A toolkit including open source package was also developed by Ibict to be distributed to potential data providers. BDTD has been integrated with the international initiative: the Networked Digital Library of Thesis and Dissertation (NDLTD). Discussions in the paper address various issues related to project design, development and management as well as the role played by Ibict. Conclusions highlight some important lessons learned to date and challenges for the future in expanding the BDTD project.

Uso do software Estradas para determinação do espaçamento entre desaguadouros em estradas não pavimentadas do interior de Goiás

Estradas não pavimentadas correspondem a aproximadamente 90% da malha rodoviária brasileira. Estas, na maioria das vezes, são construídas sem a realização de estudos prévios, estando sujeitas a vários tipos de problemas. Um dos principais fatores de deterioração dessas vias é a ineficiência do sistema de drenagem. Neste trabalho simulou-se o espaçamento entre desaguadouros em estradas não pavimentadas, utilizando-se um software desenvolvido com base num modelo matemático de dimensionamento de sistemas de drenagem em estradas não pavimentadas. Utilizaram-se valores de erodibilidade, tensão crítica de cisalhamento e massa específica para diferentes solos de estradas, localizadas no Estado de Goiás. Simularam-se cenários considerando alterações na declividade (1, 5, 10 e 15%) e na seção transversal do canal com relações entre altura e largura de 1:1, 1:2, 1:5 e 1:10. O modelo respondeu sensivelmente às alterações na declividade, na seção transversal do canal e nas de resistência do solo. Os espaçamentos obtidos indicaram que, estradas com declividades inferiores a 5%, mesmo com elevados valores de erodibilidade permitiram espaçamentos viáveis em aspectos construtivos. No entanto, para as declividades de 10 e 15%, os espaçamentos, na maioria dos casos, apresentaram dimensões reduzidas, tornando-se impraticáveis, sendo necessário, nestes casos, proteção do canal ou alteração de suas características hidráulicas.

Dinâmica da acumulação de capacidades inovadoras: evidências de empresas de software no Rio de janeiro e em São Paulo

São escassos estudos sobre a dinâmica da acumulação de capacidades inovadoras. Este artigo examina o tema em oito empresas de software em São Paulo e Rio de Janeiro, encontrando: diferenças inter e intraempresariais em termos da direção e taxa de acumulação de capacidade para funções tecnológicas específicas; acúmulo de capacidade tecnológica mais rápido em empresas mais jovens; e decréscimo das taxas de acumulação tecnológica à medida que as empresas se aproximam de níveis mais inovadores de capacidades, demonstrando a potencialidade para aceleração do processo. Tais evidências são relevantes para o entendimento da acumulação tecnológica e fornecem uma noção do tempo necessário para se obterem benefícios de esforços de aprendizagem e construção de capacidade inovadora.

Atratividade de projetos de software livre: importância teórica e estratégias para administração

Milhares de Projetos de Software Livre (PSL) foram e continuam sendo criados na Internet. Esse cenário aumenta as oportunidades de colaboração tanto quanto acirra a concorrência por usuários e contribuidores, que elevariam esses projetos a níveis superiores aos que seriam alcançados por seus fundadores sozinhos. E dado que o aprimoramento por meio de colaboração é o principal objetivo dos fundadores de PSL, a importância de entender e administrar a capacidade de atrair usuários e contribuidores fica estabelecida. Para auxiliar pesquisadores e fundadores nesse desafio, o conceito de atratividade é introduzido neste artigo, que desenvolve um ferramental teórico-gerencial sobre as causas, indicadores e consequências da atratividade, viabilizando sua administração estratégica.

Knowledge cities: a taxonomy for analyzing software and information service clusters

Software and information services (SIS) have become a field of increasing opportunities for international trade due to the worldwide diffusion of a combination of technological and organizational innovations. In several regions, the software industry is organized in clusters, usually referred to as "knowledge cities" because of the growing importance of knowledge-intensive services in their economy. This paper has two primary objectives. First, it raises three major questions related to the attractiveness of different cities in Argentina and Brazil for hosting software companies and to their impact on local development. Second, a new taxonomy is proposed for grouping clusters according to their dominant business segment, ownership pattern and scope of operations. The purpose of this taxonomy is to encourage further studies and provide an exploratory analytical tool for analyzing software clusters.

PROPOSTA DE INVESTIGAÇÃO SOBRE O USO DE SOFTWARE NO SUPORTE À INOVAÇÃO EM SERVIÇOS

RESUMOEste artigo examina os objetivos, instrumentos e características das inovações habilitadas por Tecnologias da Informação e Comunicação (TICs) no Brasil, enfatizando as tecnologias utilizadas, os canais habilitados pelas ferramentas digitais, os processos de aprendizado para inovação e as mudanças organizacionais necessárias para o uso de ferramentas avançadas. A metodologia consiste na adaptação de taxonomias existentes para os propósitos específicos da pesquisa e a realização de uma pesquisa de campo com o auxílio do software Atlas.ti. Os resultados mostram que as inovações habilitadas por TIC não constituem eventos isolados e pontuais, uma vez que alteram processos, formas de relacionamento com parceiros e clientes, e requerem uma maior integração de funções organizacionais. Importantes diferenças foram observadas em função do porte da empresa, da internacionalização das operações, da capacitação técnica e do grau de acesso a ferramentas proprietárias.

BASS 4: a software system for ergonomic design and evaluation of working hours

OBJECTIVE: To extend an existing computer programme for the evaluation and design of shift schedules (BASS 3) by integrating workload as well as economic aspects. METHODS: The redesigned prototype BASS 4 includes a new module with a suitable and easily applicable screening method (EBA) for the assessment of the intensity of physical, emotional and cognitive workload components and their temporal patterns. Specified criterion functions based on these ratings allow for an adjustment of shift and rest duration according to the intensity of physical and mental workload. Furthermore, with regard to interactive effects both workload and temporal conditions, e.g. time of day, are taken into account. In a second new module, important economic aspects and criteria have been implemented. Different ergonomic solutions for scheduling problems can now also be evaluated with regard to their economic costs. RESULTS: The new version of the computer programme (BASS 4) can now simultaneously take into account numerous ergonomic, legal, agreed and economic criteria for the design and evaluation of working hours. CONCLUSIONS: BASS 4 can now be used as an instrument for the design and the evaluation of working hours with regard to legal, ergonomic and economic aspects at the shop floor as well as in administrative (e.g. health and safety inspection) and research problems.

Readability of medicinal package leaflets: a systematic review

OBJECTIVE To review studies on the readability of package leaflets of medicinal products for human use.METHODS We conducted a systematic literature review between 2008 and 2013 using the keywords “Readability and Package Leaflet” and “Readability and Package Insert” in the academic search engine Biblioteca do Conhecimento Online,comprising different bibliographic resources/databases. The preferred reporting items for systematic reviews and meta-analyses criteria were applied to prepare the draft of the report. Quantitative and qualitative original studies were included. Opinion or review studies not written in English, Portuguese, Italian, French, or Spanish were excluded.RESULTS We identified 202 studies, of which 180 were excluded and 22 were enrolled [two enrolling healthcare professionals, 10 enrolling other type of participants (including patients), three focused on adverse reactions, and 7 descriptive studies]. The package leaflets presented various readability problems, such as complex and difficult to understand texts, small font size, or few illustrations. The main methods to assess the readability of the package leaflet were usability tests or legibility formulae. Limitations with these methods included reduced number of participants; lack of readability formulas specifically validated for specific languages (e.g., Portuguese); and absence of an assessment on patients literacy, health knowledge, cognitive skills, levels of satisfaction, and opinions.CONCLUSIONS Overall, the package leaflets presented various readability problems. In this review, some methodological limitations were identified, including the participation of a limited number of patients and healthcare professionals, the absence of prior assessments of participant literacy, humor or sense of satisfaction, or the predominance of studies not based on role-plays about the use of medicines. These limitations should be avoided in future studies and be considered when interpreting the results.

Rapid Characterization of S. mansoni Expression Library Clones of Potential Interest

A S. mansoni adult worm cDNA expression library was screened with sera from baboons in a early phase after infection. The clones that were positive with the early infection sera were examined for reactivity with pre-infection sera and heterologous infection sera. In order to discriminate a positive antibody reaction from the reactivity due to residual anti-E. coli antibodies, an unrelated cDNA clone was plated with the positive clone. The unrelated clone provided the negative background and the contrast necessary to discern a positive antibody reaction. In this way, we were able to eliminate selected clones that were positive with the pre-infection sera or heterologous infection sera. This characterization of the expression library clones enabled us to quickly target only clones with the desired pattern of antibody reactivity for sequencing, subcloning, and expressing