468 research outputs found

    Uso de imagens de radar na estimativa da temperatura do ar.

    Get PDF
    O trabalho propĂ”e um mĂ©todo para a estimativa da temperatura do ar baseado em um MDE construĂ­do a partir de dados do radar SRTM. Segundo os autores a estimativa de temperaturas medidas mensais e anuais do ar a partir de coordenadas geogrĂĄficas e altitude foi pesquisada por diversos autores. Apesar do grande nĂșmero de trabalhos, muitos estados brasileiros carecem de informaçÔes climatolĂłgicas de temperatura do ar, que poderiam ser geradas a partir de equaçÔes de estimativas associadas a modelos digitais de elevação (MDE)

    Vortex motion in a finite-size easy-plane ferromagnet and application to a nanodot

    Full text link
    We study the motion of a non-planar vortex in a circular easy-plane ferromagnet, which imitates a magnetic nanodot. Analysis was done using numerical simulations and a new collective variable theory which includes the coupling of Goldstone-like mode with the vortex center. Without magnetic field the vortex follows a spiral orbit which we calculate. When a rotating in-plane magnetic field is included, the vortex tends to a stable limit cycle which exists in a significant range of field amplitude B and frequency ω\omega for a given system size L. For a fixed ω\omega, the radius R of the orbital motion is proportional to L while the orbital frequency Ω\Omega varies as 1/L and is significantly smaller than ω\omega. Since the limit cycle is caused by the interplay between the magnetization and the vortex motion, the internal mode is essential in the collective variable theory which then gives the correct estimate and dependency for the orbit radius R∌BL/ωR\sim B L/\omega. Using this simple theory we indicate how an ac magnetic field can be used to control vortices observed in real magnetic nanodots.Comment: 15 pages (RevTeX), 14 figures (eps

    Distinction of representations via Bruhat-Tits buildings of p-adic groups

    Full text link
    Introductory and pedagogical treatmeant of the article : P. Broussous "Distinction of the Steinberg representation", with an appendix by Fran\c{c}ois Court\`es, IMRN 2014, no 11, 3140-3157. To appear in Proceedings of Chaire Jean Morlet, Dipendra Prasad, Volker Heiermann Ed. 2017. Contains modified and simplified proofs of loc. cit. This article is written in memory of Fran\c{c}ois Court\`es who passed away in september 2016.Comment: 33 pages, 4 figure

    Comparação dos modelos digitais de elevação gerados com dados SRTM e cartas IBGE na escala 1:250.000 na região da Bacia do Camanducaia no Estado de São Paulo.

    Get PDF
    O estudo comparou os MDEs, os mapas de declividade e os mapas hipsomĂ©tricos produzidos pela SRTM com aqueles gerados pelas cartas do IBGE. A ĂĄrea estudada integra a bacia do Camanducaia, que limita-se como Estado de SĂŁo Paulo a leste e JaguariĂșna a oeste, abrangendo Holambra, JaguariĂșna, Santo AntĂŽnio de Posse, Pedreira, Amparo, Serra Negra, Monte Alegre do Sul, Socorro, Pinhalzinho e Pedra Bela

    Teor de carotenoides em nutricosméticos: anålise da adequação e qualidade do produto.

    Get PDF
    O objetivo deste trabalho foi verificar a adequação dos nutricosmĂ©ticos contendo carotenoides em sua formulação em relação aos teores de B-caroteno, luteĂ­na, licopeno e zeaxantina, considerando-se as quantidades declaradas pelos fabricantes. Dezenove nutricosmĂ©ticos foram adquiridos no comĂ©rcio varejista do municĂ­pio do Rio de Janeiro, em 2012. Duas metodologias de extração foram aplicadas, variando-se de acordo com o tipo de invĂłlucro (cĂĄpsula), veĂ­culos (excipientes) e carotenoides presentes. A quantificação e determinação do perfil de carotenoides nas amostras foram realizadas por cromatografia lĂ­quida de alta eficiĂȘncia com mĂ©todo validado e acreditado. Quatro amostras das 19 analisadas estavam dentro dos limites estabelecidos pelas Boas PrĂĄticas de Fabricação (90 a 110%). As demais amostras revelaram conteĂșdo inadequado de carotenoides e, consequentemente, falhas no controle de qualidade para a produção dos nutricosmĂ©ticos. Desta forma, esta pesquisa demonstra que este setor deve ser objeto de atenção especial da vigilĂąncia sanitĂĄria, com necessidade de estabelecer legislação especĂ­fica para regulamentar a fabricação, a rotulagem e a propaganda destes produtos

    Vortices in the presence of a nonmagnetic atom impurity in 2D XY ferromagnets

    Full text link
    Using a model of nonmagnetic impurity potential, we have examined the behavior of planar vortex solutions in the classical two-dimensional XY ferromagnets in the presence of a spin vacancy localized out of the vortex core. Our results show that a spinless atom impurity gives rise to an effective potential that repels the vortex structure.Comment: 6 pages, 2 figures, RevTex

    Proteomic analysis of soybean leaves in a compatible and an incompatible interaction with Phakopsora pachyrhizi.

    Get PDF
    Asian soybean rust (ASR), which is incited by the fungus Phakopsora pachyrhizi, is considered one of the most aggressive diseases to the soybean culture. There are no commercial cultivars immune to the pathogen and the control measure currently used is the application of fungicides that harms the environment and increases production costs. For a better understanding of the host?s response to the pathogen at the molecular level, two soybean genotypes were analyzed (PI561356, resistant to ASR and Embrapa 48, susceptible) at 72 hours and 192 hours after inoculation with spores of P. pachyrhizi. Leaf protein profiles of the plants were compared by two-dimensional electrophoresis associated with mass spectrometry (MS). Twenty-two protein spots presented different levels when the two treatments were compared (inoculated vs. non-inoculated). From those, twelve proteins were identified by MS analysis. Some of them are involved in metabolic pathways related to plant defense against pathogens, as in the case of carbonic anhydrase, 1-deoxy-D-xylulose- 5-phosphate reductoisomerase, fructose-bisphosphate aldolase and glutamine synthetase. The possible biochemical-physiological meanings of our findings are discussed

    Neutrino Masses and Lepton Flavour Violation in Thick Brane Scenarios

    Get PDF
    We address the issue of lepton flavour violation and neutrino masses in the ``fat-brane'' paradigm, where flavour changing processes are suppressed by localising different fermion field wave-functions at different positions (in the extra dimensions) in a thick brane. We study the consequences of suppressing lepton number violating charged lepton decays within this scenario for lepton masses and mixing angles. In particular, we find that charged lepton mass matrices are constrained to be quasi-diagonal. We further consider whether the same paradigm can be used to naturally explain small Dirac neutrino masses by considering the existence of three right-handed neutrinos in the brane, and discuss the requirements to obtain phenomenologically viable neutrino masses and mixing angles. Finally, we examine models where neutrinos obtain a small Majorana mass by breaking lepton number in a far away brane and show that, if the fat-brane paradigm is the solution to the absence of lepton number violating charged lepton decays, such models predict, in the absence of flavour symmetries, that charged lepton flavour violation will be observed in the next round of rare muon/tau decay experiments.Comment: 33 pages, 9 eps figure
    • 

    corecore