Perturbation of strong Feller semigroups and well-posedness of semilinear stochastic equations on Banach spaces

We prove a Miyadera-Voigt type perturbation theorem for strong Feller semigroups. Using this result, we prove well-posedness of the semilinear stochastic equation dX(t) = [AX(t) + F(X(t))]dt + GdW_H(t) on a separable Banach space E, assuming that F is bounded and measurable and that the associated linear equation, i.e. the equation with F = 0, is well-posed and its transition semigroup is strongly Feller and satisfies an appropriate gradient estimate. We also study existence and uniqueness of invariant measures for the associated transition semigroup.Comment: Revision based on the referee's comment

Relativistic Tunneling Through Two Successive Barriers

We study the relativistic quantum mechanical problem of a Dirac particle tunneling through two successive electrostatic barriers. Our aim is to study the emergence of the so-called \emph{Generalized Hartman Effect}, an effect observed in the context of nonrelativistic tunneling as well as in its electromagnetic counterparts, and which is often associated with the possibility of superluminal velocities in the tunneling process. We discuss the behavior of both the phase (or group) tunneling time and the dwell time, and show that in the limit of opaque barriers the relativistic theory also allows the emergence of the Generalized Hartman Effect. We compare our results with the nonrelativistic ones and discuss their interpretation.Comment: 7 pages, 3 figures. Revised version, with a new appendix added. Slightly changes in the styles and captions of Figures 1 and 2. To appear in Physical Review

O processo de humanização do ambiente hospitalar centrado no trabalhador

The humanization of the hospital environment cannot be achieved if the focus is directed only to external motivational factors or just to the user. A humanization program needs to be assumed as a participative construction process that demands respect and valuing of the human being that provides care. Based on human and ethics values and principles and on Freire's ideas, this study aims to describe how a humanization process was unchained in a hospital, initially centering on the worker, through the collective discussion of concrete problems and the construction of horizontal, reflective dialogical relations. The proposal made possible a better comprehension of the meaning of humanization, with the rescue of previous initiatives of humanization, the elaboration of a databank in which there is room for subjectivity, the creation of warm collective areas and a closer relationship between directors and workers.La humanización del ambiente hospitalario no se concretiza si estuviera centrada únicamente en factores de motivación externas o solamente en el usuario. Un programa de humanización necesita ser asumido como un proceso de construcción participativa que requiere respeto y valorización del ser humano que cuida. Basados en valores y principios humanos y éticos y en ideas de Freire, este trabajo tuvo por objetivo explicitar cómo se desencadenó el proceso de humanización, en una institución hospitalaria, centrado, inicialmente, en el trabajador, mediante la problematización colectiva de la realidad concreta y la construcción de relaciones dialógicas, horizontales y reflexivas. La propuesta posibilitó mayor comprensión del significado de humanización, con el rescate de iniciativas anteriores de humanización ya adoptada, la adopción de un Banco de Ideas como un espacio para la emergencia de subjetividades, la organización de ambientes colectivos acogedores y una mayor aproximación entre la dirección y los trabajadores.A humanização do ambiente hospitalar não se concretiza se estiver centrada unicamente em fatores motivacionais externos ou somente no usuário. Um programa de humanização necessita ser assumido como um processo de construção participativa que requer respeito e valorização do ser humano que cuida. Pautado em valores e princípios humanos e éticos e em idéias de Freire, este trabalho tem por objetivo explicitar como se desencadeou um processo de humanização, numa instituição hospitalar, centrado, inicialmente, no trabalhador, mediante a problematização coletiva da realidade concreta e a construção de relações dialógicas, horizontais e reflexivas. A proposta possibilitou maior compreensão do significado de humanização, com o resgate de iniciativas anteriores de humanização já adotadas, a adoção de um Banco de Idéias como um espaço para a emersão de subjetividades, a organização de ambientes coletivos acolhedores e uma maior aproximação entre a direção e trabalhadores

Compactness and asymptotic behavior in nonautonomous linear parabolic equations with unbounded coefficients in Rd\R^d

We consider a class of second order linear nonautonomous parabolic equations in R^d with time periodic unbounded coefficients. We give sufficient conditions for the evolution operator G(t,s) be compact in C_b(R^d) for t>s, and describe the asymptotic behavior of G(t,s)f as t-s goes to infinity in terms of a family of measures mu_s, s in R, solution of the associated Fokker-Planck equation

De l’art d’éditer les fabliaux. Quelques observations à propos d’un compte rendu concernant l’édition du fabliau De cele qui se fist foutre sur la fosse son mari

With a little delay, the authors answer to a not very objective review of the edition of the fabliau De celle qui se fist foutre sur la la fosse son mari. At the same time, they propose some brief reflections on the following general theme: how to propose a critical edition of the fabliaux

LETRAMENTO CRÍTICO ENTRE 2007 E 2008: UMA PESQUISA BIBLIOGRÁFICA VIA BANCO DE TESES DA CAPES

LETRAMENTO CRÍTICO ENTRE 2007 E 2008: UMA PESQUISABIBLIOGRÁFICA VIA BANCO DE TESES DA CAPESThis article is a sequence of the bibliographic research made by REIS (2008)and seeks to analyze Master’s and Doctorate Degrees’ papers about critical literacypublished by the CAPES’ thesis database, through the reading of its abstracts. Fromthis, we verify in each areas of knowledge the concept of critical literacy is beingapplied and emphasizes the analysis of the development of the critical literacy studies inthe filed of foreign language, in special of English.Este trabalho é uma continuação da pesquisa bibliográfica feita por REIS (2008) e visa a analisar trabalhos de Mestrado e Doutorado sobre letramento crítico registradas pelo banco de teses da CAPES, por meio da leitura de seus resumos. A partir disso, verifica em que áreas do conhecimento o conceito de letramento crítico está sendo aplicado e dá ênfase à análise do desenvolvimento de estudos sobre letramento crítico no campo do ensino de língua estrangeira, em especial da língua inglesa.

Integrated pest management strategies used in stored grain.

Managing pests of stored grain has become an increasingly serious problem in Brazil. This is because grain production has more than doubled in the last 10 years and insect pests have become resistant to protectant insecticides. In the same period, use of phosphine fumigation has increased rapidly and is now widely practised. However, control failures with phosphine have become common as fumigations are undertaken in unsealed silos and in situations where sanitation is poor. As a consequence, many parcels of grain are repeatedly fumigated. In response to this situation, Embrapa initiated a programme to introduce IPM into the central grain storage facilities. Our strategy included the following elements: (a) changing behaviour through training of the storage facilities personnel; (b) improving knowledge of stored grain unit; (c) cleanliness of the equipment and premises and, after that, spray residual insecticide; (d) identification of grain-stored pests; (e) resistance tests; (f) insecticide treatment and fumigation; (g) sampling and monitoring the grain. The IPM programme was introduced into two storage facilities in Paraná State. Following successful implementation of IPM, these facilities were able to supply insect-free grain and had a bonus from the market. The success of these companies led to the adoption of IPM by other storage companies. IPM systems are now running in 13 separate facilities owned by nine companies. To support the programme, Embrapa Wheat has trained more than 1,000 stored grain operators and released an IPM manual and website www.cnpt.embrapa.br/pesquisa/entomologia/mip. The challenges to be pursue for the next fifteen years of the research team are sealing silos, measure phosphine concentrations, pure PH3 applications, new protectants as spinosad (the bacterial derivate pesticide), offering technologies to guarantee high quality grains with insect free and residues free in the international market