Shared Information -- New Insights and Problems in Decomposing Information in Complex Systems

How can the information that a set ${X_{1},...,X_{n}}$ of random variables contains about another random variable $S$ be decomposed? To what extent do different subgroups provide the same, i.e. shared or redundant, information, carry unique information or interact for the emergence of synergistic information? Recently Williams and Beer proposed such a decomposition based on natural properties for shared information. While these properties fix the structure of the decomposition, they do not uniquely specify the values of the different terms. Therefore, we investigate additional properties such as strong symmetry and left monotonicity. We find that strong symmetry is incompatible with the properties proposed by Williams and Beer. Although left monotonicity is a very natural property for an information measure it is not fulfilled by any of the proposed measures. We also study a geometric framework for information decompositions and ask whether it is possible to represent shared information by a family of posterior distributions. Finally, we draw connections to the notions of shared knowledge and common knowledge in game theory. While many people believe that independent variables cannot share information, we show that in game theory independent agents can have shared knowledge, but not common knowledge. We conclude that intuition and heuristic arguments do not suffice when arguing about information.Comment: 20 page

Poetry – Minimal Anthology

This volume carries the major distinction of being the only existing English translation of Fernando Pessoa’s poems to recreate both the rhyme and the metrical schemes of the original

Extracting samples of high diversity from thematic collections of large gene banks using a genetic-distance based approach.

Background Breeding programs are usually reluctant to evaluate and use germplasm accessions other than the elite materials belonging to their advanced populations. The concept of core collections has been proposed to facilitate the access of potential users to samples of small sizes, representative of the genetic variability contained within the gene pool of a specific crop. The eventual large size of a core collection perpetuates the problem it was originally proposed to solve. The present study suggests that, in addition to the classic core collection concept, thematic core collections should be also developed for a specific crop, composed of a limited number of accessions, with a manageable size. Results The thematic core collection obtained meets the minimum requirements for a core sample - maintenance of at least 80% of the allelic richness of the thematic collection, with, approximately, 15% of its size. The method was compared with other methodologies based on the M strategy, and also with a core collection generated by random sampling. Higher proportions of retained alleles (in a core collection of equal size) or similar proportions of retained alleles (in a core collection of smaller size) were detected in the two methods based on the M strategy compared to the proposed methodology. Core sub-collections constructed by different methods were compared regarding the increase or maintenance of phenotypic diversity. No change on phenotypic diversity was detected by measuring the trait "Weight of 100 Seeds", for the tested sampling methods. Effects on linkage disequilibrium between unlinked microsatellite loci, due to sampling, are discussed. Conclusions Building of a thematic core collection was here defined by prior selection of accessions which are diverse for the trait of interest, and then by pairwise genetic distances, estimated by DNA polymorphism analysis at molecular marker loci. The resulting thematic core collection potentially reflects the maximum allele richness with the smallest sample size from a larger thematic collection. As an example, we used the development of a thematic core collection for drought tolerance in rice. It is expected that such thematic collections increase the use of germplasm by breeding programs and facilitate the study of the traits under consideration. The definition of a core collection to study drought resistance is a valuable contribution towards the understanding of the genetic control and the physiological mechanisms involved in water use efficiency in plants

Textile effluente treatment though oxidation via activated humidity

Diversos problemas envolvem as estações de tratamento de efluentes têxteis, principalmente o baixo nível de eficiência quanto a remoção da cor. Em função de normas mais rigorosas que estão sendo estabelecidas, as indústrias têxteis têm que encontrar métodos efetivos para a descoloração de seus efluentes. O presente trabalho investigou através de estudos em laboratório, a remoção de cor destes efluentes através da oxidação por via úmida ativada (Processo de Oxidação Avançada-AOP) utilizando como oxidante o peróxido de hidrogênio, ativado pela radiação ultravioleta. A fotodegradação foi realizada em batelada em um reator equipado com uma lâmpada de vapor de mercúrio de média pressão, de imersão. Três diferentes doses de peróxido de hidrogênio foram testadas (15, 30 e 45 mg/L) em amostras com diferentes pHs (3, 7 e 11). A degradação da cor mostrou seguir uma cinética de pseudo primeira ordem, sendo as condições mais adequadas para o pH alcalino, na presença de 45 mg/L de H2O2.Several problems are found in the textile effluent treatment stations, mainly the low level of efficiency concerning color removal. As a result of more rigorous standards that have been established the textile industries are forced to find effective methods for discoloration of their effluents. This work concerns a laboratory investigation on the removal of color from these effluents through oxidation by activated wet process, (Advanced Oxidation Process-OAP), using hydrogen peroxide as an oxidizing agent, activated by ultraviolet radiation. Photo-degradation was carried out in a bark in a reactor equipped with an immersion mercury vapor lamp at medium pressure. Three different dosages of hydrogen peroxide were tested (15, 30 and 45 mg/L) using samples with different pHs (3, 7, 11). Color degradation proved to follow a kinetics of pseudo first order, being the most appropriate conditions for an alkaline pH, in the presence of 45 mg/L of H2O2

Avaliação da Conservação de Couve Minimamente Processada pela Medida do Tempo de Relaxação Transversal da RMN.

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