Learning Bounded Treewidth Bayesian Networks with Thousands of Variables

We present a method for learning treewidth-bounded Bayesian networks from data sets containing thousands of variables. Bounding the treewidth of a Bayesian greatly reduces the complexity of inferences. Yet, being a global property of the graph, it considerably increases the difficulty of the learning process. We propose a novel algorithm for this task, able to scale to large domains and large treewidths. Our novel approach consistently outperforms the state of the art on data sets with up to ten thousand variables

Os olhos e a rede

Globo.comUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

A Degradação das Aguas Continentais Sob a Perspectiva dos Pescadores Artesanais de Bacia de Campos

Este artigo discute os impactos da degradação dos cursos de água da bacia hidrográfica do Rio Paraíba do Sul, no Norte do Estado do Rio de Janeiro. O enfoque empírico traz o problema pela percepção dos pescadores artesanais, que atuam nesta região e dependem da água para a sua sobrevivência. Assim, busca-se dar ouvidos a uma parcela significativa de trabalhadores que dependem deste recurso e que não se expressam pelos canais apropriados, como os comitês de bacia e suas entidades de classe, como as colônias e associações. O texto tem como base as informações coletadas junto aos pescadores, em reuniões comunitárias e grupos focais, realizadas através de um projeto de mitigação ambiental. Identificou-se as opiniões dos pescadores artesanais e suas perspectivas sobre a degradação, com as ações desenvolvidas pelo poder público.

La caza de la ballena. Su influencia en los usos y costumbres desde la Edad Media.

La caza de la ballena, ha influido en el hombre vasco desde el Medievo. Para conocer los usos y costumbres de nuestro pueblo, nos tenemos que fijar en las fuentes indirectas. Así, nos hemos basado en los escudos de las villas costeras, con el motivo de la caza de la ballena, así como en una rica tradición oral. Ambas fuentes han llegado hasta nuestros días, sin apenas variaciones, lo cual indica la importancia de esta práctica.Balearen harrapaketak, Erdi Arotik aurrera euskaldunen bizitzan eragin haundia izan zuen. Gure herriaren ohiturak ezagutzeko zeharkako iturrietara jo behar dugu. Euskal kostaldeko herrien harmarri eta ahozko tradizioari buruz ari gara. Gaur arte aldatu gabe iraun badute, balearen harrapaketa zein garrantzitsua izan den erakusten digute.La chasse de la baleine a axercé une influence sur l'homme basque depuis le Moyen Âge. Pour connaître les usages et coutumes de notre peuple, nous devons nous appuyer dans des sources indirectes. Ainsi donc, nous nous sommes basé dans les écus des villes de la côte, avec le motif de la chasse de la baleine, ainsi qu'une riche tradition oral. Les deux sources, ont arrivé à nous jours, presque sans variations, c'est qu'indique l'importance de cette practique.Whaling, has influenced Basque man since Mediaeval time. So as to know our people customs, we must use indirect fountains. In this way, we have fixed our knowledge in the shields from coast villages, with whaling motives, and even in a richfull oral traditions. Both fountains have reached to our days, scarcely changed, sing of the importance of this practice

Photorefractive keratectomy for low myopia correction using different ablation profiles

Objectives: The present study compares the results obtained with single zone PRK versus multiple zones PRK for treating low myopia. Methods: Nineteen patients presenting spherical equivalent up to 6.00 diopters of myopia, were submitted to PRK using two different approaches. Ramdomly one eye received a 6.0 mm spherical ablation (SZ) while the fellow eye was treated with two optical zones, 6.0 mm and 6.5 mm (MZ). All the procedures aimed to correct total spherical equivalent. Follow-up was carried out for at least 6 months. Results: The multizone group (MZ) presented a preoperative mean spherical equivalent of -2.87 diopters, ranging from -1.25 to -4.62D. In the single zone group, the mean spherical equivalent was -2.78 diopters, ranging from -1.37 to -4.62D. No significant difference was observed between the two groups considering final spherical equivalent (p=0.391). In the first postoperative month, 84% of the patients in the MZ group and 95% in the SZ group presented uncorrected visual acuity equal to or better than 20/40. No difference was detected regarding time necessary to achieve best uncorrected vision. Conclusion: Results obtained using different ablation profiles were similar in regard to spherical equivalent, induced astigmatism and complications. A better final uncorrected visual acuity trend was observed in the SZ group but it was not considered clinically significant. We believe that any of the evaluated approaches are valued methods for treating low myopia.Objetivos: O presente estudo prospectivo compara os resultados obtidos pela ceratectomia fotorrefrativa com uma ou duas zonas de ablação para tratamento de baixa miopia. Métodos: Dezenove pacientes com graus de miopia até 6,00 dioptrias foram submetidos a PRK com diferentes perfis de ablação em cada olho. Foi realizado tratamento esférico com uma única zona de ablação de 6,0 mm, ao passo que o outro olho recebeu tratamento com duas zonas de ablação, sendo uma de 6,0 mm e outra de 6,5 mm. Todos os tratamentos foram programados para correção total do equivalente esférico. Resultados: No grupo multizona (MZ), o equivalente esférico pré-operatório foi em média de -2,87 dioptrias (-1,25 a -4,62D). No grupo submetido à cirurgia com uma única zona de ablação (ZU), o equivalente esférico pré-operatório foi de -2,78 dioptrias (-1,37 a -4,62 D). Não foi observada diferença significante entre os resultados obtidos nos dois grupos com relação ao equivalente esférico final (p = 0,391). No primeiro mês de pós-operatório, 84% dos pacientes do grupo MZ (múltiplas zonas de ablação) e 95% do grupo ZU (única zona de ablação), apresentaram acuidade visual sem correção melhor ou igual a 20/40. Com relação ao tempo transcorrido até se atingir a melhor acuidade visual, não houve diferença significante entre os dois grupos (p = 0,53). Conclusão: Os resultados obtidos utilizando-se diferentes perfis de ablação para tratamento de baixas miopias foram equivalentes no que diz respeito a equivalente esférico final, indução de astigmatismo e incidência de complicações. O estudo conclui que não foi possível observar diferença estatisticamente significante entre os dois grupos, podendo-se utilizar qualquer um dos procedimentos no tratamento das baixas miopias.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de OftalmologiaUNIFESP, EPM, Depto. de OftalmologiaSciEL

ET-1 plasma levels, choroidal thickness and multifocal electroretinogram in retinitis pigmentosa

Aim To assess the relationship between both photoreceptor function and choroidal thickness and endothelin-1 (ET-1) plasma levels in patients with early stage retinitis pigmentosa (RP). Main methods We compared 24 RP patients (14 males and 10 females), 25 to 42 years of age (mean age: 34 ± 7 years) with 24 healthy controls (12 males and 12 females) aged between 28 and 45 years (mean 36 ± 6.8 years). All patients underwent visual field test, electroretinogram and multifocal-electroretinogram and choroidal thickness measurement by using spectral domain optical coherence tomography. Key findings RP patients had a visual acuity of 0.95, a mean defect of the visual field of − 7.90 ± 1.75 dB, a pattern standard deviation index of 6.09 ± 4.22 dB and a b-wave ERG amplitude of 45.08 ± 8.24 μV. Notably RP subjects showed significantly increased ET-1 plasma levels and reduced choroidal thickness compared with controls: respectively, 2.143 ± 0.258 pg/ml vs. 1.219 ± 0.236 pg/ml; p < 0.002 and 226.75 ± 76.37 μm vs. 303.9 ± 39.87 μm; p < 0.03. Spearman's correlation test highlighted that the increase of ET-1 plasma levels was related with the decrease of choroidal thickness (r = − 0.702; p < 0.023) and the increase of implicit time in both ring 2 (r = − 0.669; p < 0.034) and ring 3 (r = − 0.883; p < 0.007) of mfERG. Significance Increased ET-1 plasma levels may play a key role in the impairment of retinal and choroidal blood flow due to the vasoconstriction induced by ET-1. This could lead to worsening of the abiotrophic process of the macular photoreceptors

Soro autólogo para doenças da superfície ocular

Autologous serum has been used to treat dry eye syndrome for many years. It contains several growth factors, vitamins, fibronectin and other components that have been considered important for corneal and conjunctival integrity. Serum eye drops are usually prepared as an unpreserved blood solution. The serum is by nature well tolerated and its biochemical properties are somewhat similar to natural tears. Autologous serum eye drops have been reported to be effective for the treatment of severe dry eye-related ocular surface disorders (Sjögren's syndrome), and also other entities such as superior limbic keratoconjunctivitis, graft-versus-host disease, Stevens-Johnson syndrome, ocular cicatricial pemphigoid, recurrent or persistent corneal erosions, neurotrophic keratopathy, Mooren's ulcer, aniridic keratopathy, filtering blebs after trabeculectomy, and post-keratorefractive surgery. The purpose of this study is to review the recently published literature on ocular surface diseases treated with human autologous serum eye drops.O soro autólogo tem sido adotado como uma nova abordagem para tratar síndrome do olho seco porque contém vitaminas, alguns fatores de crecimento e fibronectina que são considerados importantes contribuintes para integridade corneana e conjuntival. Colírio de soro autólogo é produzido sem preservativo. O soro é não-alérgico e suas propriedades bioquímicas são similares à lágrima. O soro autólogo tópico tem sido relatado efetivo para o tratamento de olho seco grave relacionado a distúrbios da superfície ocular como na síndrome de Sjögren, ceratoconjuntivite límbica superior, doença do enxerto versus hospedeiro, síndrome de Stevens-Johnson, procedimentos cerato-refrativos, erosão corneana persistente ou recorrente, ceratopatia neurotrófica, úlcera de Mooren, ceratopatia associada à aniridia, e bolhas filtrantes após trabeculectomia. O objetivo do presente estudo é revisar a literatura recentemente publicada sobre doenças da superficie ocular tratadas com soro autológo tópico.The Johns Hopkins University School of Medicine Fellow in Cornea and Refractive Surgery at the Wilmer Ophthalmological InstituteUniversidade Federal de São Paulo (UNIFESP) Departamento de OftalmologiaThe Johns Hopkins University School of Medicine Wilmer Ophthalmological InstituteUNIFESP, Depto. de OftalmologiaSciEL

A Neurogenetic Algorithm Based on Rational Agents

Lately, a lot of research has been conducted on the automatic design of artificial neural networks (ADANNs) using evolutionary algorithms, in the so-called neuro-evolutive algorithms (NEAs). Many of the presented proposals are not biologically inspired and are not able to generate modular, hierarchical and recurrent neural structures, such as those often found in living beings capable of solving intricate survival problems. Bearing in mind the idea that a nervous system's design and organization is a constructive process carried out by genetic information encoded in DNA, this paper proposes a biologically inspired NEA that evolves ANNs using these ideas as computational design techniques. In order to do this, we propose a Lindenmayer System with memory that implements the principles of organization, modularity, repetition (multiple use of the same sub-structure), hierarchy (recursive composition of sub-structures), minimizing the scalability problem of other methods. In our method, the basic neural codification is integrated to a genetic algorithm (GA) that implements the constructive approach found in the evolutionary process, making it closest to biological processes. Thus, the proposed method is a decision-making (DM) process, the fitness function of the NEA rewards economical artificial neural networks (ANNs) that are easily implemented. In other words, the penalty approach implemented through the fitness function automatically rewards the economical ANNs with stronger generalization and extrapolation capacities. Our method was initially tested on a simple, but non-trivial, XOR problem. We also submit our method to two other problems of increasing complexity: time series prediction that represents consumer price index and prediction of the effect of a new drug on breast cancer. In most cases, our NEA outperformed the other methods, delivering the most accurate classification. These superior results are attributed to the improved effectiveness and efficiency of NEA in the decision-making process. The result is an optimized neural network architecture for solving classification problems