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Inverse source reconstruction problems offer great potential for applications of interest to engineering, such as the identification of polluting sources, and to medicine, such as electroencephalography, to cite at least two relevant examples. From a mathematical point of view, the identification of a concentrated source (intensity and location) corresponds to the identification of the centroid (location) and size (intensity) of a distributed source. On the other hand, from a numerical point of view, it is observed that the use of domain discretization methods is intrinsically associated with the introduction of numerical noise in reconstruction algorithms, which is strongly inadvisable since inverse problems are reckoned to be ill-posed. The objective of this work is to explore, in the context of a Poisson problem and taking into account a numerical point of view, a new reconstruction algorithm based on the method of fundamental solutions, where a source point adequately represents the pointwise source within the domain. The inverse problem is reformulated as an optimization problem solved through a genetic algorithm. Finally, numerical examples are performed to analyze the accuracy of the proposed algorithm for two and three dimensions.

What a strain is and how many strains make up a natural bacterial population remain elusive concepts despite their apparent importance for assessing the role of intra-population diversity in disease emergence or response to environmental perturbations. To advance these concepts, we sequenced 138 randomly selectedSalinibacter ruberisolates from two solar salterns and assessed these genomes against companion short-read metagenomes from the same samples. The distribution of genome-aggregate average nucleotide identity (ANI) values among these isolates revealed a bimodal distribution, with significantly lower occurrence of values between 99.2% and 99.8% relative to ANI >99.8% or 99.99% and shared gene-content >99.0% to define strains. Using these thresholds and extrapolating from how many metagenomic reads each genomovar uniquely recruited, we estimated that –although our 138 isolates represented about 80% of theSal. ruberpopulation– the total population in one pond is composed of 5,500 to 11,000 genomovars, the great majority of which appear to be rarein situ. These data also revealed that the most frequently recovered isolate in lab media was often not the most abundant genomovarin situ, suggesting that cultivation biases are significant, even in cases that cultivation procedures are thought to be robust. Preliminary analyses of available genomes revealed that the thresholds used for defining strains and distinct intra-species units (genomovars) may be broadly applicable to additional bacterial species.Significance StatementStrains are the smallest distinguishable units within a microbial species. Strains that carry unique gene content often underly the emergence of disease outbreaks and the response of the species to environmental perturbations. Therefore, a major challenge in microbiome research across environmental and clinical settings is to evaluate how many strains of the same species coexist in nature and how dominant strains emerge from this diversity. Unfortunately, the available theoretical concept of strain is not directly applicable to culture-independent surveys. Here, we provide such a practical definition for strain and use it to show that that the number of strains making up a natural bacterial population may be large, in the order of a few thousands, but not infinite.

Background The CO2-concentrating mechanism associated to Crassulacean acid metabolism (CAM) alters the catalytic context for Rubisco by increasing CO2 availability and provides an advantage in particular ecological conditions. We hypothesized about the existence of molecular changes linked to these particular adaptations in CAM Rubisco. We investigated molecular evolution of the Rubisco large (L-) subunit in 78 orchids and 144 bromeliads with C3 and CAM photosynthetic pathways. The sequence analyses were complemented with measurements of Rubisco kinetics in some species with contrasting photosynthetic mechanism and differing in the L-subunit sequence. Results We identified potential positively selected sites and residues with signatures of co-adaptation. The implementation of a decision tree model related Rubisco specific variable sites to the leaf carbon isotopic composition of the species. Differences in the Rubisco catalytic traits found among C3 orchids and between strong CAM and C3 bromeliads suggested Rubisco had evolved in response to differing CO2 concentration. Conclusions The results revealed that the variability in the Rubisco L-subunit sequence in orchids and bromeliads is composed of coevolving sites under potential positive adaptive signal. The sequence variability was related to δ13C in orchids and bromeliads, however it could not be linked to the variability found in the kinetic properties of the studied species.

Problemas inversos de reconstrucao de fontes apresentam grande potencial para aplicacoes de interesse da engenharia, como na identificacao de fontes poluidoras, e da medicina, como na eletroencefalografia, para citar dois importantes exemplos. Do ponto de vista matematico, a identificacao de uma fonte concentrada (intensidade e localizacao) cor- responde a identificacao do centroide (localizacao) e do tamanho (intensidade) de uma fonte distribuida. Por outro lado, do ponto de vista numerico, observa-se que o uso de metodos de discretizacao de dominio esta intrinsecamente associado a introducao de ruidos numericos nos algoritmos de reconstrucao de fontes concentradas, o que e fortemente desaconselhavel, uma vez que problemas inversos sao reconhecidamente mal postos. O objetivo deste trabalho e explorar numericamente, no contexto de um problema de Poisson, um novo algoritmo de reconstrucao baseado no metodo das solucoes fundamentais, onde a fonte concentrada pode ser adequadamente representada por um ponto no interior do dominio. O problema inverso e entao reformulado como um problema de otimizacao que e resolvido atraves de um algoritmo genetico. Finalmente, a acuracia do algoritmo proposto e ilustrada atraves de alguns experimentos numericos realizados para o caso bidimensional.

Objective In 2006, an age estimation method was proposed utilizing Bayesian inference to interpret age-progressive changes in the acetabulum. This was accompanied by the IDADE2 software to facilitate calculations. However, the MS-DOS operating system on which the software was based became obsolete. The main goal of this article is to present the new IDADE2, which incorporates web-based facilities. Materials and methods The original IDADE2 has been re-written in R and presented as a web page. As in the original, this web page uses Bayesian inference to estimate age of unidentified individuals. The materials used to create the reference datasets of this web page include acetabular scores from documented skeletal samples from Spain (n = 24♀ and 52♂), Portugal (n = 317♀ and 294♂), and the US (n = 370♀ and 456♂). Results The IDADE2 website has eight sections. Six of these are informative to guide the user. The other two (Option 1 and Option 2) are dedicated to estimating age at death. Option 1 allows users to estimate the age of individual(s) in their test sample based on our reference data of acetabular scores. Option 2 allows users to estimate age from the acetabulum with their own reference and test collections or-if the users prefer-another age marker and method of choice. Discussion The IDADE2 website is applicable both to forensic anthropological casework on single individuals and to bioarchaeological analyses of large skeletal samples. This website is easy to use and freely accessible, responding to previous critiques and incorporating method advancements.

An issue that frequently arises in structural optimization problems considering eigenvalues is the non differentiability of repeated eigenvalues. In order to overcome this difficulty, several schemes were already presented in the literature. However, these approaches generally have other disadvantages such as the inclusion of additional constraints, the inaccuracy of representation of smallest/largest eigenvalues, the significant increase in the computational effort required and incompatibility with finite differences schemes. In this paper a smooth p-norm approximation for the smallest magnitude eigenvalue is employed. The resulting approximation is differentiable, converges to the exact value as p is increased and is very simple to use (it is also compatible with finite difference schemes). Although the use of smooth approximations for maximum/minimum operators is a classical approach, for some reason it was not extensively studied in the context of structural optimization considering eigenvalues. Three examples concerning topology optimization for the maximization of the first natural vibration frequency of plane stress structures are presented in order to show the effectiveness of the proposed approach.

Este trabalho foi realizado nos dois Tribunais do Juri de Joao Pessoa, entre os anos de 2015 e 2017. A partir da realizacao de entrevistas semiestruturadas com os juizes leigos, apresentamos uma reflexao acerca do funcionamento desses tribunais e do poder estabelecido entre os envolvidos na producao da sentenca. Em seguida, utilizamos um modelo de contagio, amplamente utilizado na Sociologia Matematica e ajustado com os achados da pesquisa, a fim de explorar as dinâmicas do contagio social entre os jurados. Tanto a pesquisa qualitativa quanto os resultados da aplicacao do modelo permitem concluir que os vicios de permanencia do corpo de jurados, traduzidos na distincao entre juizes leigos neofitos e profissionais, podem comprometer significativamente a isencao do julgamento, em flagrante conflito com os principios norteadores do tribunal do juri.

Este artigo propõe uma construção alternativa para o conceito de derivada de uma função, um dos conceitos fundamentais do Cálculo Diferencial, aproximando-se do Método das Fluxões de Newton, apresentado no século XVIII através de forte apelo intuitivo. Evitar a construção demasiadamente técnica do conceito de derivada através de um limite indeterminado cuja abstração e formalismo constituem dificuldades adicionais para os alunos foi a principal motivação para este trabalho. Amparados ainda pelo desenvolvimento histórico, acreditamos que a abordagem ora proposta constitua uma alternativa bastante natural tanto para a significação do conceito de derivada, quanto para o desenvolvimento de alguns aspectos técnicos do conteúdo programático de Cálculo, como calcular derivadas e obter as regras de derivação, por exemplo. O principal objetivo deste trabalho é, portanto, fornecer fundamentos que corroborem com esta afirmação., Interacções, vol. 13 n.º 46 (2017): NÚMERO ESPECIAL - Diferentes olhares sobre a educação

Due to recent advances in genetic manipulation, transgenic mosquitoes may be a viable alternative to reduce some diseases. Feasibility conditions are obtained by simulating and analyzing mathematical models that describe the behavior of wild and transgenic populations living in the same geographic area. In this paper, we present a reaction–diffusion model in which the reaction term is a nonlinear function that describes the interaction between wild and transgenic mosquitoes, considering the zygosity, and the diffusive term that represents a nonuniform spatial spreading characterized by a random diffusion parameter. The resulting nonlinear system of partial differential equations is numerically solved using the sequential operator splitting technique, combining the finite element method and Runge-Kutta method. This scheme is numerically implemented considering uncertainty in the diffusion parameters of the model. Several scenarios simulating spatial release strategies of transgenic mosquitoes are analyzed, demonstrating an intrinsic association between the transgene frequency in the total population and the strategy adopted.

O objetivo deste trabalho é em saber como está ocorrendo à adaptação do conteúdo e o método de ensino e como a disciplina Contabilidade de Custo está sendo ministrada no curso de graduação em Ciências Contábeis, em face do panorama econômico da perda do peso relativo da indústria manufatureira no conjunto da economia brasileira. Esta pesquisa classifica-se como exploratória. O resultado da pesquisa permite sugestão de que, por parte dos docentes, a disciplina Contabilidade de Custos deva ser explorada de forma diferenciada e os conteúdos adaptados à realidade do mercado de trabalho, com exercícios e indicações bibliográficas, no que concerne a contabilização e análise dos fatos relacionados aos custos das empresas prestadoras de serviços e das empresas atuantes no setor agropecuário.

The topological derivative provides the sensitivity of a given shape functional with respect to an infinitesimal (non smooth) domain perturbation at an arbitrary point of the domain. Classically, this derivative comes from the second term of the topological asymptotic expansion, dealing only with infinitesimal perturbations. However, for practical applications, we need to insert perturbations of finite size. Therefore, we consider one more term in the expansion which is defined as the second order topological derivative. In order to present these ideas, in this work we calculate first as well as second order topological derivatives for the total potential energy associated to the Laplace’s equation, when the domain is perturbed with a hole. Furthermore, we also study the effects of different boundary conditions on the hole: Neumann and Dirichlet (both homogeneous). In the Neumann’s case, the second order topological derivative depends explicitly on higher-order gradients of the state solution and also implicitly on the point where the hole is nucleated through the solution of an auxiliary problem. On the other hand, in the Dirichlet’s case, the first order topological derivative depends explicitly on the state solution as well as implicitly through the solution of an auxiliary problem, and the second order topological derivative depends only explicitly on the solution associated to the original problem. Finally, we present two simple examples showing the influence of both terms in the second order topological asymptotic expansion for each case of boundary condition on the hole.

Motivation: Throughout evolution, homologous proteins have common regions that stay semi-rigid relative to each other and other parts that vary in a more noticeable way. In order to compare the increasing number of structures in the PDB, flexible geometrical alignments are needed, that are reliable and easy to use. Results: We present a protein structure alignment method whose main feature is the ability to consider different rigid transformations at different sites, allowing for deformations beyond a global rigid transformation. The performance of the method is comparable with that of the best ones from 10 aligners tested, regarding both the quality of the alignments with respect to hand curated ones, and the classification ability. An analysis of some structure pairs from the literature that need to be matched in a flexible fashion are shown. The use of a series of local transformations can be exported to other classifiers, and a future golden protein similarity measure could benefit from it. Availability: A public server for the program is available at http://dmi.uib.es/ProtDeform/. Contact: jairo@uib.es Supplementary information: All data used, results and examples are available at http://dmi.uib.es/people/jairo/bio/ProtDeform.Supplementary data are available at Bioinformatics online.

We introduce a new family of metrics for graphs of fixed size, based on counting-independent sets. Our definition is simpler and easier to calculate than the edge ideal metric family defined by Llabrés and Rosselló without loosing any of its abstract properties. We contrast them on some examples with graphs that represent protein secondary and three-dimensional (3D) structures. We conclude that although the edge ideal metrics are faster to calculate on some sparse graphs, in general, the independent set metrics are more tractable.

A new polygon decomposition into regular and singular regions is defined; it is a concept that is useful for skeleton extraction and part analysis of elongated shapes. Polygon regions that are narrow according to the Voronoi diagram of the polygon are extended through the boundary that is adjacent and quasiparallel. Regular regions are the narrow ones surrounded by smooth quasiparallel contour segments, while singular regions are the polygon regions that are not regular. We present an efficient algorithm to calculate the decomposition and make a comparative study with previous algorithms.

Zou and Yan have recently developed a skeletonization algorithm of digital shapes based on a regularity/singularity analysis; they use the polygon whose vertices are the boundary pixels of the image to compute a constrained Delaunay triangulation (CDT) in order to find local symmetries and stable regions. Their method has produced good results but it is slow since its complexity depends on the number of contour pixels. This paper presents an extension of their technique to handle arbitrary polygons, not only polygons of short edges. Consequently, not only can we achieve results as good as theirs for digital images, but we can also compute skeletons of polygons of any number of edges. Since we can handle polygonal approximations of figures, the skeletons are more resilient to noise and faster to process.

An algorithm that decomposes a line image into singular and regular regions is presented. We define a contour trapezoid as the building block for the regular regions, and postulate a maximal trapezoid set as the core of the regular regions. Then, we describe an algorithm that calculates a maximal trapezoid set of a polygon and show how to use it to find a skeleton of a polygonal approximation of a contour. Several experiments are explained to show the behavior of the new concept on real images as compared to previous algorithms and criteria.

PONTE, Jairo Rocha Ximenes. O público não-estatal na comunicação social como possibilidade de aprofundamento da democracia constitucional brasileira. NOMOS: Revista do Programa de Pós-Graduação em Direito da UFC, Fortaleza, v.30, n.2, 2010, p.85-107. The fundamental rights and the other stony clauses, mechanisms of preservation of the spirit of the constitution and the minorities inside of a political society, only exist throughout their interpretation and application by the constitutional jurisdiction. It is not possible to disregard the strong political aspect of the constitutional jurisdiction, even more when we have in sight that fundamental rights are principiological norms with indeterminate content, which is determinable only in the concrete case, what gives the judge a great edge of choice. To do not let the constitutional jurisdiction completely move away from the yearnings of the political community, resulting in rupture of the democratic principle, Härbele proposes the participation of the community of interprets in the fulfilling of the meaning of the constitutional text. If, on the one hand, the model of open society of you interpret is more democratic, on the other hand, it is also more vulnerable the influxes of a hegemonic ideology. It is necessary to understand the phenomenon of the mass communication because of its great capacity of uniform the representation of the reality, as well as to think about the situation of the great concentration in the sector of the communication in Brazil, having in sight the international debate on the new world order of information and communication. With the goal to establish a reality where the media function more for the increase of democracy that for its decrease, this work discusses the importance and the possibilities of a public non-state communication system, side by side with the state and private systems. Os direitos fundamentais e as demais cláusulas pétreas, mecanismos de preservação do espírito da constituição e das minorias dentro de uma sociedade política, não existem concretamente senão mediante sua interpretação e aplicação pela jurisdição constitucional. Não é possível desconsiderar o forte teor político da jurisdição constitucional, ainda mais quando se tem em vista que direitos fundamentais são normas principiológicas de conteúdo indeterminado, determináveis apenas no caso concreto, o que dá ao julgador uma grande margem de escolha. Para que a jurisdição constitucional não se afaste completamente dos anseios da comunidade política, redundando em ruptura do princípio democrático, Härbele propõe a participação da comunidade de interpretes no preenchimento do sentido do texto constitucional. Se por um lado o modelo de sociedade aberta de interpretes é mais democrático, por outro é também mais vulnerável a influxos de uma ideologia hegemônica. Surge a necessidade de compreender o fenômeno da comunicação de massas pela sua grande capacidade de uniformizar de representação da realidade, como também refletir sobre a situação de grande concentração no setor da comunicação social no Brasil, tendo em vista as discussões internacionais sobre a nova ordem mundial da informação e da comunicação. Para que se possa alcançar uma realidade em que os media funcionem mais para o aprofundamento da democracia que no seu escamoteio, discute-se a importância e as possibilidades de um sistema de comunicação público não estatal, em complementaridade com os sistemas estatal e privado.

A segmentation-free approach to OCR is presented as part of a knowledge-based word interpretation model. It is based on the recognition of subgraphs homeomorphic to previously defined prototypes of characters. Gaps are identified as potential parts of characters by implementing a variant of the notion of relative neighborhood used in computational perception. Each subgraph of strokes that matches a previously defined character prototype is recognized anywhere in the word even if it corresponds to a broken character or to a character touching another one. The characters are detected in the order defined by the matching quality. Each subgraph that is recognized is introduced as a node in a directed net that compiles different alternatives of interpretation of the features in the feature graph. A path in the net represents a consistent succession of characters. A final search for the optimal path under certain criteria gives the best interpretation of the word features. Broken characters are recognized by looking for gaps between features that may be interpreted as part of a character. Touching characters are recognized because the matching allows nonmatched adjacent strokes. The recognition results for over 24,000 printed numeral characters belonging to a USPS database and on some hand-printed words confirmed the method's high robustness level. >

A method for the recognition of multifont printed characters is proposed, giving emphasis to the identification of structural descriptions of character shapes using prototypes. Noise and shape variations are modeled as series of transformations from groups of features in the data to features in each prototype. Thus, the method manages systematically the relative distortion between a candidate shape and its prototype, accomplishing robustness to noise with less than two prototypes per class, on average. The method uses a flexible matching between components and a flexible grouping of the individual components to be matched. A number of shape transformations are defined, including filling of gaps, so that the method handles broken characters. Also, a measure of the amount of distortion that these transformations cause is given. Classification of character shapes is defined as a minimization problem among the possible transformations that map an input shape into prototypical shapes. Some tests with hand-printed numerals confirmed the method's high robustness level. >