3,821 research outputs found
A historical and environmental study of the urban space production and reproduction process in Cuiaba, Mato Grosso state
Este trabalho é resultante de uma pesquisa que avalia a relação entre os processos de produção e reprodução do espaço urbano, considerando a interação entre os fenômenos históricos e ambientais, a partir do entendimento dos aspectos climáticos e geográficos na formação e espacialização da cidade contemporânea, apresentando como estudo de caso a cidade de Cuiabá, capital do Estado de Mato Grosso. A pesquisa ainda determina ferramentas metodológicas de intervenção urbana na região central e histórica da Prainha, em Cuiabá-MT, ocupada desde o século XVIII. Fonte: http://periodicos.pucminas.br/index.php/Arquiteturaeurbanismo/article/view/1006. Acesso em: 21 fev. 2013.O projeto de intervenção urbana para a cidade de Cuiabá-MT foi objeto central da dissertação de mestrado defendida no dia 20/11/2007, no Programa de Pós-graduação em Geografia da UFMT, Cuiabá-MT. Sob o título “Parque Linear da Prainha, Cuiabá-MT: uma ruptura de paradigmas na intervenção urbana”, Geovany Jessé Alexandre da Silva (2007) defende os limites e potencialidades transformadoras da vida urbana, economia, sociedade, ritmos, ritos, impactos ambientais, clima urbano etc., tangíveis através de um projeto de reinvenção e reabilitação urbana contemporânea.Este trabalho é resultante de uma pesquisa que avalia a relação entre os processos de produção e reprodução do espaço urbano, considerando a interação entre os fenômenos históricos e ambientais, a partir do entendimento dos aspectos climáticos e geográficos na formação e espacialização da cidade contemporânea, apresentando como estudo de caso a cidade de Cuiabá, capital do Estado de Mato Grosso. A pesquisa ainda determina ferramentas metodológicas de intervenção urbana na região central e histórica da Prainha, em Cuiabá-MT, ocupada desde o século XVIII. ______________________________________________________________________________________ ABSTRACTThis work is the result of a survey that assesses the relationship between the processes of production and reproduction of urban space, considering the interaction between the historical and environmental phenomena from the understanding of climatic and geographical aspects in training and spatialization of the contemporary city, presenting the case study as the city of Cuiabá, the state capital of Mato Grosso. The research also provides tools for urban intervention in the central region and history of Prainha, in Cuiabá, occupied since the eighteenth century
Sistema P2P de protección de la privacidad en motores de búsqueda basado en perfiles de usuario
Los motores de búsqueda en Internet (como por ejemplo Google, Bing, Yahoo, AOL, etc.) almacenan en sus servidores las consultas efectuadas por los usuarios. Esta información les permite crear perfiles, y así mejorar el servicio ofrecido (resultados personalizados, sugerencias, correcciones, etc.). Sin embargo, estos perfiles pueden también comprometer el derecho a la privacidad de los usuarios. La información que contienen puede servir para identificar a un usuario y así relacionar su identidad con consultas personales y confidenciales. Por esta razón, es necesario aplicar alguna medida de control que proteja la privacidad de los usuarios de motores de búsqueda. Este artículo presenta un entorno P2P diseñado para permitir que los usuarios se agrupen en diferentes categorías en función de su perfil y puedan ejecutar un protocolo para proteger su privacidad
Pulse propagation in decorated granular chains: An analytical approach
We study pulse propagation in one-dimensional chains of spherical granules
decorated with small grains placed between large granules. The effect of the
small granules can be captured by replacing the decorated chains by undecorated
chains of large granules of appropriately renormalized mass and effective
interaction between the large granules. This allows us to obtain simple
analytic expressions for the pulse propagation properties using a
generalization of the binary collision approximation introduced in our earlier
work [Phys. Rev. E in print (2009); Phys. Rev. E {\bf 69}, 037601 (2004)]Comment: 10 pages and 12 figure
Observation of two-wave structure in strongly nonlinear dissipative granular chains
In a strongly nonlinear viscous granular chain under conditions of loading
that exclude stationary waves (e.g., impact by a single grain) we observe a
pulse that consists of two interconnected but distinct parts. One is a leading
narrow "primary pulse" with properties similar to a solitary wave in a "sonic
vacuum." It arises from strong nonlinearity and discreteness in the absence of
dissipation, but now decays due to viscosity. The other is a broad, much more
persistent shock-like "secondary pulse" trailing the primary pulse and caused
by viscous dissipation. The medium behind the primary pulse is transformed from
a "sonic vacuum" to a medium with finite sound speed. When the rapidly decaying
primary pulse dies, the secondary pulse continues to propagate in the "sonic
vacuum," with an oscillatory front if the viscosity is relatively small, until
its eventual (but very slow) disintegration. Beyond a critical viscosity there
is no separation of the two pulses, and the dissipation and nonlinearity
dominate the shock-like attenuating pulse which now exhibits a nonoscillatory
front
Recombinant viruses as tools to induce protective cellular immunity against infectious diseases
Infections by intracellular pathogens such as viruses, some bacteria and many parasites, are cleared in most cases after activation of specific T cellular immune responses that recognize foreign antigens and eliminate infected cells. Vaccines against those infectious organisms have been traditionally developed by administration of whole live attenuated or inactivated microorganisms. Nowadays, research is focused on the development of subunit vaccines, containing the most immunogenic antigens from the particular pathogen. However, when purified subunit vaccines are administered using traditional immunization protocols, the levels of cellular immunity induced are mostly low and not capable of eliciting complete protection against diseases caused by intracellular microbes. In this review, we present a promising alternative to those traditional protocols, which is the use of recombinant viruses encoding subunit vaccines as immunization tools. Recombinant viruses have several interesting features that make them extremely efficient at inducing immune responses mediated by T-lymphocytes. This cellular immunity has recently been demonstrated to be of key importance for protection against malaria and AIDS, both of which are major targets of the World Health Organization for vaccine development. Thus, this review will focus in particular on the development of new vaccination protocols against these diseases. [Int Microbiol 2004; 7(2):83–94
Disentangling the phylogenetic and ecological components of spider phenotypic variation
An understanding of how the degree of phylogenetic relatedness influences the ecological similarity among species is crucial to inferring the mechanisms governing the assembly of communities. We evaluated the relative importance of spider phylogenetic relationships and ecological niche (plant morphological variables) to the variation in spider body size and shape by comparing spiders at different scales: (i) between bromeliads and dicot plants (i.e., habitat scale) and (ii) among bromeliads with distinct architectural features (i.e., microhabitat scale). We partitioned the interspecific variation in body size and shape into phylogenetic (that express trait values as expected by phylogenetic relationships among species) and ecological components (that express trait values independent of phylogenetic relationships). At the habitat scale, bromeliad spiders were larger and flatter than spiders associated with the surrounding dicots. At this scale, plant morphology sorted out close related spiders. Our results showed that spider flatness is phylogenetically clustered at the habitat scale, whereas it is phylogenetically overdispersed at the microhabitat scale, although phylogenic signal is present in both scales. Taken together, these results suggest that whereas at the habitat scale selective colonization affect spider body size and shape, at fine scales both selective colonization and adaptive evolution determine spider body shape. By partitioning the phylogenetic and ecological components of phenotypic variation, we were able to disentangle the evolutionary history of distinct spider traits and show that plant architecture plays a role in the evolution of spider body size and shape. We also discussed the relevance in considering multiple scales when studying phylogenetic community structure.An understanding of how the degree of phylogenetic relatedness influences the ecological similarity among species is crucial to inferring the mechanisms governing the assembly of communities. We evaluated the relative importance of spider phylogenetic rel9519FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOsem informaçãosem informaçãoWe would like to thank M. Belisário, T.N. Bernabé, T.S. Coser, R. Marques, F. Moreira, D. Mota and E.S. Soeiro for their invaluable assistance in the field work. We thank N. Kraft, D.B. Provete, D.N. Reznick and anonymous reviewers for constructive comme
User profiling in web interfaces adaptivity
[ES] La Web se ha convertido en un modelo de computación ampliamente aceptado, que
está provocando una migración de los sistemas de información tradicionales a este
nuevo contexto. Un claro ejemplo de esta situación ocurre en los sistemas de
comercio electrónico, que aprovechan las facilidades de interactivas de la Web para
el desarrollo de su actividad. En esta nueva ola de aplicaciones Web nos
encontramos con nuevos retos, habida cuenta de las mayores prestaciones en
cuanto a funcionalidad e interacción que el usuario exige en el software. Los
contenidos, tradicionalmente estáticos, que conformaban la Web, se ven ahora
sustituidos por contenidos generados dinámicamente, que favorecen la naturaleza
evolutiva y cambiante propia de estos sistemas. Relacionado con esto, comienzan a
surgir los servicios personalizados, que intentan mostrar a los usuarios aquella
información en la que están más interesados, utilizando para ello el conocimiento que
le permite inferir al sistema como adaptarse automáticamente al usuario, esto es, se
cuenta con un perfil de cada usuario del sistema. En el presente trabajo se va a
hacer una introducción a las técnicas de creación y gestión de perfiles de usuario,
con el claro propósito de aplicarlas en un contexto personalizado y adaptativo de
comercio electrónico.
[EN] Web systems are a widely accepted computation model, which is causing a migration
of the traditional information system to this context. E-Commerce systems are a
representative example of this situation; these ones take advantage of the interactive
facilities of the Web system to develop their activities. This new trend of Web
applications introduce new challenges, which are derived from the growth of the
users’ functionality and interaction requirements. The traditionally static information
contents, which formed the Web, are now substituted by contents generated on the
fly, which promote the evolutionary and changeable nature of the Web systems.
Related to this situation, personalized Web services appear that try to offer the most
interesting data for each particular user. In order to achieve this goal, these systems
use the needed knowledge to infer how they will be able to adapt themselves to the
users’ preferences. This means that the system has a profile of each user. In this
paper we are going to introduce to the profile creation and management techniques,
with the aim of applying them in personalized and adaptive e-commerce context
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