Concentric Characterization and Classification of Complex Network Nodes: Theory and Application to Institutional Collaboration

Differently from theoretical scale-free networks, most of real networks present multi-scale behavior with nodes structured in different types of functional groups and communities. While the majority of approaches for classification of nodes in a complex network has relied on local measurements of the topology/connectivity around each node, valuable information about node functionality can be obtained by Concentric (or Hierarchical) Measurements. In this paper we explore the possibility of using a set of Concentric Measurements and agglomerative clustering methods in order to obtain a set of functional groups of nodes. Concentric clustering coefficient and convergence ratio are chosen as segregation parameters for the analysis of a institutional collaboration network including various known communities (departments of the University of S\~ao Paulo). A dendogram is obtained and the results are analyzed and discussed. Among the interesting obtained findings, we emphasize the scale-free nature of the obtained network, as well as the identification of different patterns of authorship emerging from different areas (e.g. human and exact sciences). Another interesting result concerns the relatively uniform distribution of hubs along the concentric levels, contrariwise to the non-uniform pattern found in theoretical scale free networks such as the BA model.Comment: 15 pages, 13 figure

Urban environmental quality and wellbeing in the context of incomplete urbanization in Brazil: integrating directly experienced ecosystem services into planning

The benefits of urban greenspace to residents are increasingly recognized as important to planning for sustainable and healthy cities. However, the way that people interact with and benefit from urban greenspace is context dependent and conditioned by a range of social and material factors. This paper applies and expands the ecosystems services based approach to understanding urban environmental quality and the way in which greenspace is appropriated by residents in the context of incomplete urbanization in three peri-urban target areas in Brazil. We develop and employ the notion of indirect (scientifically detected) and directly experienced ecosystems services, and undertake a science based ecosystem services assessment and a qualitative analysis of interviews, walking narratives and images captured with a smartphone application to understand what functions urban greenspace serves in the daily life of the studied neighborhoods. Findings demonstrate how elements of urban greenspace and what can be termed ecosystem services serve both material and signifying functions and produce subjective and collective benefits and dis-benefits that hinge on aspects of livability such as quality of urban service delivery, housing status and perceptions of crime and neighborhood character. We identify factors that enable, hinder and motivate both active material and interpretative interactions with urban greenspace. The findings suggest that the relationship between ecosystem service provision and wellbeing is better understood as reciprocal rather than one way. Although at the neighborhood scale, fear of crime and poor access to urban services can hinder positive engagements with urban greenspace and experienced benefits form ES, urban squares and fringe vegetation is also being appropriated to address experienced disadvantages. Presently however these local interactions and ecosystem service benefits are overlooked in formal planning and conservation efforts and are increasingly compromised by growing population density and environmental degradation. We make recommendations for a nuanced assessment of the material and interpretative human-nature interactions and associated ecosystem services in an urban context, and discuss the potential for planning initiatives that could be employed to articulate and nurture these important interactions in our target areas

The Role of Presentation Media and Perspective on Direction Giving

Research on spatial cognition has tried to understand how perspective (route vs. survey) and media (visual vs. verbal) influence people\u27s spatial cognition on different tasks (e.g., map drawing, navigation, semantic and distance estimation) when materials are presented simultaneously. However, less research has focused on how those spatial features influence people\u27s direction giving when materials are presented sequentially, one piece at a time. In the present study, participants were presented with fragments of sentences and map segments. After learning the materials, they were asked to give directions using their own words or including cardinal terms. As hypothesized, participants provided more accurate directions when presented with visual (map) than verbal (text) media; this finding is consistent with other research studies that show the superiority of visual over verbal media in many spatial cognition tasks. Exploratory analysis showed that participants used significantly more relative terms and streets in their route directions in the map condition compared to the text condition. However, results revealed no differences in route direction accuracy between participants who learned Without layouts and those who learned With layouts. Participants also included more streets and repeated materials fewer times when asked to give directions using their own words than when asked to include cardinal terms. Overall, results indicate that presentation media and spatial perspectives impact the quality and content of route directions

Hipocrisia, moralidade e caráter em Nietzsche.

O presente artigo trata do problema ético nietzscheano da constituição de um caráter de exceção sob duas frentes: primeiramente, sob um viés negativo, como contraposição à moralidade do rebanho. Depois, em seu momento construtivo ou afirmativo, propriamente como criação de si. O leitmotiv dessa dupla apresentação é o da defesa de aspectos daquilo que associamos à noção de hipocrisia como chave de interpretação para essa constituição. Primeiramente, como arte dissimulação, na forma de um refúgio do indivíduo em meio à moralidade do rebanho. Depois, como arte do ator, nas práticas que Nietzsche associa à constituição de si.This article deals with Nietzsche’s ethical problem of the constitution of an exceptional character, under two fronts: first, under a negative bias, as opposed to the morality of the herd. Later, on its constructive or affirmative time, properly as creation of self. The leitmotif of this double presentation is the defense of aspects from what we associate with the concept of hypocrisy as a key to an interpretation of that constitution. First, as an art of dissimulation, in the form of an individual's refuge amidst the morality of the herd. Later, as the actor's art, in the practices which Nietzsche associates to the self-constitution

Modelos espaciais de especiação

Orientador: Marcus Aloizio Martinez de AguiarTese (doutorado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: A impressionante diversidade observada na natureza nos faz pensar quais processos podem ser responsáveis por tamanha variedade. Responder esta questão foi o objetivo de muito biólogos evolutivos, que tentaram descobrir os processos olhando para os padrões que eles poderiam gerar. O desenvolvimento de modelos teóricos, em particular modelos baseados em indivíduo, é indispensável para lidar com esta questão, pois apenas com modelos podemos isolar processos específicos em um ambiente controlado, o que não é completamente possível em experimentos naturais, e em um tempo realizável. Nesta tese eu investiguei quais são os padrões gerados por um modelo de especiação baseado em indivíduo no qual apenas processos neutros e o espaço estão regulando a dinâmica populacional. A população evoluiu sob as influências combinadas de reprodução sexuada, mutação e dispersão. No primeiro capítulo, desenvolvemos um algoritmo que registra as relações de ancestralidade-descendência entre pares de indivíduos da comunidade final, e um algoritmo que registra os tempos exatos de especiação e extinção das espécies. Com ambas as informações foi possível construir genealogias e filogenias, a partir das quais padrões macroevolutivos foram obtidos, servindo como um referencial de evolução neutra. O segundo capítulo foi dedicado a usar esta nova informação filogenética do modelo para investigar se diferentes contextos geográficos de especiação (parapátrica e simpátrica) deixam assinaturas distintas nos padrões macroevolutivos de diversificação, como a simetria de árvores e a velocidade da diversificação. Os resultados das simulações foram comparados com dados empíricos de radiações evolutivas. O terceiro capítulo, por fim, incorporou barreiras espaciais ao modelo anterior, para buscar por possíveis assinaturas deixadas pela especiação alopátrica, com barreiras variando em tamanho e permitindo que indivíduos as cruzassem dependendo de seu tamanho. O modelo foi adaptado ao sistema particular dos macacos Platyrrhini, com o espaço modelado de modo a se ajustar à forma da América do Sul, e as barreiras representando os principais rios da região. O número de gerações foi adaptado a diferentes subfamílias e gêneros dos Platyrrhini, para examinar a "Riverine Hypothesis" com um enfoque de modelagem. Os resultados dos três capítulos mostraram que o espaço possui um papel fundamental na especiação quando processos neutros são os únicos a agir sob as populações, com o contexto geográfico da especiação deixando assinaturas nos padrões macroevolutivos emergentes. A incorporação de processos não neutros e a investigação do papel da extinção em moldar os padrões são possíveis passos seguintes para esta pesquisaAbstract: The impressive diversity observed in nature makes us wonder what processes could be responsible for so great variety. The answer to this question has been the goal of many evolutionary biologists, who have tried to discover the processes looking for the patterns they would generate. The development of theoretical models, particularly individual-based models, is imperative to address this question, as only with models we can isolate specific processes in a controled environment, something not completely possible in natural experiments, and in a feasible time. In this thesis I investigated what are the patterns generated by an individual-based model of speciation in which only neutral processes and the space are regulating the dynamics of the population. The population evolved under the combined influences of sexual reproduction, mutation and dispersal. In the first chapter, we developed an algorithm that records the ancestor-descendant relationships between each pair of individuals of the final community, and an algorithm which records the exact speciation and extinction times of species. With both information was possible to construct genealogies and phylogenies, from which macroevolutionary patterns could be derived, offering a neutral referential of evolution. The second chapter was dedicated to use this new phylogenetic information of the model to investigate if different geographical contexts of speciation (parapatric and sympatric) leave different signatures in the macroevolutionary patterns of diversification, like tree symmetry and the speed of diversification. The simulations results were compared with empirical data about evolutionary radiations. The third chapter, lastly, incorporated spatial barriers to the previous model with the goal of looking for possible signatures left by allopatric speciation, with barriers varying in sizes and allowing the crossing of individuals depending on the individual size. The model adapted to the particular system of Platyrrhini monkeys, with space modeled to fit the shape of South America, and spatial barriers representing the main rivers of the region. The number of generations was adapted to conform different subfamilies and genera of Platyrrhini monkeys, with the aim of examine the Riverine Hypothesis in a modeling approach. All results from the three chapters have showed that the space plays a fundamental role in speciation when neutral processes are the only acting upon populations, with the geographic context of speciation leaving signatures in the macroevolutionary patterns emerged. The incorporation of non neutral processes and the investigation of the role of extinction in shaping the patterns are possible next steps to this researchDoutoradoEcologiaDoutora em EcologiaCAPE