Cryptica: um software para simulação de epidemias de huanglongbing dos citros (HLB).

As dificuldades impostas ao controle do huanglongbing dos citros (HLB), determinada pela capacidade de plantas infectadas, assintomáticas, se tornarem fonte de inoculo das bactérias (Candidatus Liberibacter spp.), e agravadas pelos fatores apresentados por Francisco Laranjeira, obriga que se utilizem várias armas para mitigar os problemas causados pelo HLB. Neste contexto, a presente publicação apresenta uma importante ferramenta para avaliar possíveis cenários de disseminação da doença e poderá contribuir para consolidar programas de conscientização de controle do HLB. Ao se apoiar em modelos que se aproximam da realidade o Cryptica simula os danos causados pela doença e poderá estimular a realização de inspeção e a eliminação de plantas sintomáticas, contribuindo, portanto, para aumentar a eficiência das estratégias de controle e contenção da doença. As simulações realizadas no Cryptica são produzidas a partir da proposição de três conjuntos de parâmetros associados à paisagem (escala dos pomares), infecção e erradicação. Diante das informações até então disponíveis o software é mais um aliado nessa batalha de várias alternativas de manejo conjunto dessa doença.bitstream/item/140166/1/DOC-215-029-15-Laranjeira-Ainfo.pd

Lossy radial diffusion of relativistic Jovian electrons

The radial diffusion equation with synchrotron losses was solved by the Laplace transform method for near-equatorially mirroring relativistic electrons. The evolution of a power law distribution function was found and the characteristics of synchrotron burn-off are stated in terms of explicit parameters for an arbitrary diffusion coefficient. Emissivity from the radiation belts of Jupiter was studied. Asymptotic forms for the distribution in the strong synchrotron loss regime are provided

Paintings and Numbers: An Econometric Investigation of Sales Rates, Prices and Returns in Latin American Art Auctions

This paper uses a unique data set of Latin American paintings auctioned by Sotheby's between 1995 and 2002 to investigate several puzzles from the recent auctions literature. Our results suggest that: (1) the reputation of an artist and the provenance of the artwork, omitted variables in most previous studies, seem to be more important determinants of the sale price of a painting than standard factors, such as medium and size, (2) the opinion of art experts seems to be of limited use in predicting whether or not an artwork sells at auction, (3) there is little supporting evidence for the widespread notion that the best or more expensive artworks tend to generate above average returns (the “masterpiece effect”), although (4) there is strong evidence in our data for the declining price anomaly, or “afternoon effect.”art auctions, masterpiece effect, Latin American art, declining price anomaly

Relativistic electrons and whistlers in Jupiter's magnetosphere

The path-integrated gain of parallel propagating whistlers driven unstable by an anisotropic distribution of relativistic electrons in the stable trapping region of Jupiter's inner magnetosphere was computed. The requirement that a gain of 3 e-foldings of power balance the power lost by imperfect reflection along the flux tube sets a stably-trapped flux of electrons which is close to the non-relativistic result. Comparison with measurements shows that observed fluxes are near the stably-trapped limit, which suggests that whistler wave intensities may be high enough to cause significant diffusion of electrons accounting for the observed reduction of phase space densities. A crude estimate of the wave intensity necessary to diffuse electrons on a radial diffusion time scale yields a lower limit for the magnetic field fluctuation intensity

AM-OER: An Agile Method for the Development of Open Educational Resources

Open Educational Resources have emerged as important elements of education in the contemporary society, promoting life-long and personalized learning that transcends social, eco- nomic and geographical barriers. To achieve the potential of OERs and bring impact on education, it is necessary to increase their development and supply. However, one of the current challenges is how to produce quality and relevant OERs to be reused and adapted to different contexts and learning situations. In this paper we proposed an agile method for the development of OERs – AM-OER, grounded on agile practices from Software Engineering. Learning Design practices from the OULDI project (UK Open University) are also embedded into the AM-OER aiming at improving quality and facilitating reuse and adaptation of OERs. In order to validate AM-OER, an experiment was conducted by applying it in the development of an OER on software testing. The results showed preliminary evidences on the applicability, effectiveness and ef ciency of the method in the development of OERs

Bouncing solutions in Rastall's theory with a barotropic fluid

Rastall's theory is a modification of Einstein's theory of gravity where the covariant divergence of the stress-energy tensor is no more vanishing, but proportional to the gradient of the Ricci scalar. The motivation of this theory is to investigate a possible non-minimal coupling of the matter fields to geometry which, being proportional to the curvature scalar, may represent an effective description of quantum gravity effects. Non-conservation of the stress-energy tensor, via Bianchi identities, implies new field equations which have been recently used in a cosmological context, leading to some interesting results. In this paper we adopt Rastall's theory to reproduce some features of the effective Friedmann's equation emerging from loop quantum cosmology. We determine a class of bouncing cosmological solutions and comment about the possibility of employing these models as effective descriptions of the full quantum theory.Comment: Latex file, 14 pages, 1 figure in eps format. Typos corrected, one reference added. Published versio

A State-of-the-art Integrated Transportation Simulation Platform

Nowadays, universities and companies have a huge need for simulation and modelling methodologies. In the particular case of traffic and transportation, making physical modifications to the real traffic networks could be highly expensive, dependent on political decisions and could be highly disruptive to the environment. However, while studying a specific domain or problem, analysing a problem through simulation may not be trivial and may need several simulation tools, hence raising interoperability issues. To overcome these problems, we propose an agent-directed transportation simulation platform, through the cloud, by means of services. We intend to use the IEEE standard HLA (High Level Architecture) for simulators interoperability and agents for controlling and coordination. Our motivations are to allow multiresolution analysis of complex domains, to allow experts to collaborate on the analysis of a common problem and to allow co-simulation and synergy of different application domains. This paper will start by presenting some preliminary background concepts to help better understand the scope of this work. After that, the results of a literature review is shown. Finally, the general architecture of a transportation simulation platform is proposed

Monitoramento e nível de controle de pragas da mangueira na produção integrada de frutas.

A manga esta entre as frutas que lideram a pauta da exportação do Brasil, com destaque para a produção no Vale do São Francisco e portanto, é necessário a utilização da Produção Integrada de Frutas - PIF.1 CD-ROM