Studying Parallel Evolutionary Algorithms: The cellular Programming Case

Parallel evolutionary algorithms, studied to some extent over the past few years, have proven empirically worthwhile—though there seems to be lacking a better understanding of their workings. In this paper we concentrate on cellular (fine-grained) models, presenting a number of statistical measures, both at the genotypic and phenotypic levels. We demonstrate the application and utility of these measures on a specific example, that of the cellular programming evolutionary algorithm, when used to evolve solutions to a hard problem in the cellular-automata domain, known as synchronization

Fitness landscape of the cellular automata majority problem: View from the Olympus

In this paper we study cellular automata (CAs) that perform the computational Majority task. This task is a good example of what the phenomenon of emergence in complex systems is. We take an interest in the reasons that make this particular fitness landscape a difficult one. The first goal is to study the landscape as such, and thus it is ideally independent from the actual heuristics used to search the space. However, a second goal is to understand the features a good search technique for this particular problem space should possess. We statistically quantify in various ways the degree of difficulty of searching this landscape. Due to neutrality, investigations based on sampling techniques on the whole landscape are difficult to conduct. So, we go exploring the landscape from the top. Although it has been proved that no CA can perform the task perfectly, several efficient CAs for this task have been found. Exploiting similarities between these CAs and symmetries in the landscape, we define the Olympus landscape which is regarded as the ''heavenly home'' of the best local optima known (blok). Then we measure several properties of this subspace. Although it is easier to find relevant CAs in this subspace than in the overall landscape, there are structural reasons that prevent a searcher from finding overfitted CAs in the Olympus. Finally, we study dynamics and performance of genetic algorithms on the Olympus in order to confirm our analysis and to find efficient CAs for the Majority problem with low computational cost

Evaluation of furocoumarins as photosynthetic inhibitor by chlorophyll a fluorescence assay

The evaluations of Chorophyll a fluorescence emitted by superior plants carry structural information and photosynthetic apparatus function. Quantitative analysis apparatus of fluorescence kinetic were measured by energy flows (ABS), (TR), (ET) and (DI), known as phenomenological phenomena of OJIP test. Four furocoumarins were isolated from Ruta graveolens (Rutaceae), and chorophyll a (Chl a) fluorescence assays were performed with these compounds to evaluate the photosynthesis inhibition potential. This test was realized in spinach`s leaf discs and in Lolium perenne leaves. The results indicated the herbicide potential mainly for bergapten and chalepin.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Carlos Departamento de QuímicaUniversidade Federal de São Paulo (UNIFESP) Instituto de Ciências Ambientais, Químicas e FarmacêuticasUniversidad Nacional Autónoma de México Facultad de Química Departamento de BioquímicaUNIFESP, Instituto de Ciências Ambientais, Químicas e FarmacêuticasSciEL

Análise de Algoritmos de Indução de Árvores de Decisão

Decision trees are data structures or computational methods that enable nonparametric supervised machine learning and are used in classification and regression tasks. The aim of this paper is to present a comparison between the decision tree induction algorithms C4.5 and CART. A quantitative study is performed in which the two methods are compared by analyzing the following aspects: operation and complexity. The experiments presented practically equal hit percentages in the execution time for tree induction, however, the CART algorithm was approximately 46.24% slower than C4.5 and was considered to be more effective.Los árboles de decisión son estructuras de datos o métodos computacionales que permiten el aprendizaje automático supervisado no paramétrico y se utilizan en tareas de clasificación y regresión. El objetivo de este trabajo es presentar una comparación entre los algoritmos de inducción del árbol de decisión C4.5 y CART. Se realiza un estudio cuantitativo en el que se comparan los dos métodos mediante el análisis de los siguientes aspectos: operación y complejidad. Los experimentos presentaron porcentajes de aciertos prácticamente iguales en el tiempo de ejecución para la inducción del árbol; sin embargo, el algoritmo CART fue aproximadamente un 46,24% más lento que C4.5 y se consideró más efectivo.Árvores de decisão são estruturas de dados ou métodos computacionais que possibilitam o aprendizado de máquinas supervisionadas não-paramétricas e são usados em tarefas de classificação e regressão. O objetivo do presente artigo é apresentar uma comparação entre os algoritmos de indução de árvores de decisão C4.5 e CART. Realiza-se um estudo quantitativo no qual os dois métodos são comparados a partir de análise dos seguintes aspectos: funcionamento   e   complexidade. Verificou-se que os experimentos realizados apresentaram percentuais de acerto praticamente iguais no tempo de execução para a indução da arvore, entretanto, para um parâmetro crucial que é o tempo de processamento que é importante para muitas aplicações, o algoritmo CART foi aproximadamente 46,24% mais lento do que o C4.5 para o mesmo tipo de processamento evidenciando-se, desta forma que este pode ser considerando como mais eficiente. Recomenda-se utilizar o algoritmo C4.5 em aplicações que nas quais haja a preocupação com o tempo de processamento

Eixo quinário: um elemento de simetria presente em moléculas e quasi-cristais - um experimento didático em cristalografia

Axis of quinary symmetry occur in molecular symmetry, as in the case of fullerenes, and in crystalline symmetry, in the quasicrystals. Minerals with pentagonal faces do not have this element of symmetry, as the pyrite (FeS2) which shows a ridge that is different from the other ones, in any face of the crystal. The purpose of this paper is to demonstrate conceptual differences between pyritohedron and regular pentagonal dodecahedron symmetries, discussing students' difficulties to identify them. Also is proposed a didactic experiment with spatial models of the above-mentioned forms and the demonstration of its symmetries in clinographic projections

Mental and psychosocial predictors of toothache in Brazilian dam rupture: a cross-sectional study

Introduction: The burst of Fundão's dam in Mariana, Brazil, was one of the most significant technological disasters and, for instance, may be associated with negative consequences in oral and mental health. Objective: The present study aimed to investigate the toothache prevalence and the associated factors in disaster survivors. Method: This research is an observational, cross-sectional study carried out as a health household survey with the Mariana dam rupture survivors. Results: the study included 225 adults; age mean 45.5±17.8 years. In univariate analysis, the prevalence of toothache was 16.9% and was higher in women (20.1% versus 11.1%, p= 0.097) subjects with generalized anxiety disorders (GAD) (57.9% versus 25.8%, p≥0.0001), major depressive disorder (MDD) (50 versus 24.6%, p=0.003), post-traumatic stress disorder (PTSD) (26.3 versus 9%, p=0.006), a lower social support satisfaction (SSSS). Multivariate Data Analysis (MVA) results reveal how individuals dissatisfied with their oral appearance were 3.2 times more likely to present with toothaches (p=0.004, 95% CI-1.46-7.02). Of those affected by the disaster, survivors diagnosed with GAD were 2.5 times more likely to present tooth aches (p=0.019, 95% CI=1.16-5.48). Ultimately, the likelihood of an individual presenting with toothaches after the disaster rose to 4% to each point in the SSSS (p.=0.026,95% CI=1.005-1.081). Conclusion: We found that post-disaster survivors in Brazil presented with an elevated prevalence of toothache, and this oral symptom correlated with other dental impairments, anxiety disorder, and social support