Truncated states obtained by iteration

Quantum states of the electromagnetic field are of considerable importance, finding potential application in various areas of physics, as diverse as solid state physics, quantum communication and cosmology. In this paper we introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST. A general method to engineer TSI in the running-wave domain is employed, which includes the errors due to the nonidealities of detectors and photocounts.Comment: 10 pages, 22 figure

Scaling in a continuous time model for biological aging

In this paper we consider a generalization to the asexual version of the Penna model for biological aging, where we take a continuous time limit. The genotype associated to each individual is an interval of real numbers over which Dirac $\delta$--functions are defined, representing genetically programmed diseases to be switched on at defined ages of the individual life. We discuss two different continuous limits for the evolution equation and two different mutation protocols, to be implemented during reproduction. Exact stationary solutions are obtained and scaling properties are discussed.Comment: 10 pages, 6 figure

Peixes herbivoros da planicie inundavel do Rio Miranda, Pantanal, Mato Grosso do Sul, Brasil.

Na planicie inundavel do baixo rio Miranda, foram encontradas 12 especies de peixes de habitos alimentares herbivoros. Sao: Markiana nigripinnis, Piabucus melanostoma, Metynnis mola, Metynnis maculatus, Mylossoma paraguayensis, Mylossoma orbignyanum, Myloplus levis, Hemiodus orthonops, Leporinus elongatus, Leporinus friderici, Leporinus lacustris e Schizodon borellii. Destas, 4 apresentam importancia economica para a pesca profissional e esportiva (M. paraguayensis, M. orbinyanum, L. elongatus e L. friderici). E discutida a importancia da herbivoria na cadeia alimentar dos peixes sulamericanos.bitstream/item/37446/1/BP10.pd

Shrinking the plan. A middle-class wishful thinking in the outskirts of Lisbon

In the 1960s and 1970s, large-scale Portuguese architectural production was largely promoted by the State. This took further aspects after the 1974 revolution when housing construction became one of the pillars of the new state policy. It is in this context that Manuel Vicente develops the project for Quinta do Bacalhau in different times: 1– Before 1974 by EPUL as part of UNOR 26 of which M. Vicente was the coordinator, 2– From 1974 as a SAAL operation after the site was taken over by a residents' committee, 3– After 1976, as it was built outside the revolutionary period by a housing cooperative and financed by the state. Unlike most SAAL projects – small, contained and with low-row houses –, and despite the ideologically marked circumstances of this period, it presents somehow ostentatious. Volumes of broad and generous features, incorporation of commerce on the ground floors like a boulevard, contrast with the dominant model, thus raising some questions: – to what extent did a particular class position correspond to a certain typology, style, etc.? – wouldn't this imply an aspiration to the same “rights” as the middle-class, as far as architecture is concerned? M. Vicente remains throughout his life in an ideologically multifaceted position. Close to the Communist Party, he has a cosmopolitan experience still in the 1960s being in touch with the Western capitalism – in the United States and in Macao – and in close contact with the speculation and profit markets. It has thus a double folded stance regarding the state-sponsored housing and low standards one, as if responding to the residents were the same as responding to himself. In this communication we intend to analyse through drawings of the project how the notion of housing for “a middle-class” crossed through the project. This argument is revealed in a plan of a dwelling with dimensions close to middle-class, which is later reduced to smaller areas, but “keeping” architectural qualities.info:eu-repo/semantics/publishedVersio

Tetragonal tungsten bronze compounds: relaxor vs mixed ferroelectric - dipole glass behavior

We demonstrate that recent experimental data (E. Castel et al J.Phys. Cond. Mat. {\bf 21} (2009), 452201) on tungsten bronze compound (TBC) Ba$_2$Pr$_x$Nd$_{1-x}$FeNb$_4$O$_{15}$ can be well explained in our model predicting a crossover from ferroelectric ($x=0$) to orientational (dipole) glass ($x=1$), rather then relaxor, behavior. We show, that since a "classical" perovskite relaxor like Pb(Mn$_{1/3}$ Nb$_{2/3}$)O$_3$ is never a ferroelectric, the presence of ferroelectric hysteresis loops in TBC shows that this substance actually transits from ferroelectric to orientational glass phase with $x$ growth. To describe the above crossover theoretically, we use the simple replica-symmetric solution for disordered Ising model.Comment: 5 two-column pages, 4 figure

Diluted antiferromagnet in a ferromagnetic enviroment

The question of robustness of a network under random ``attacks'' is treated in the framework of critical phenomena. The persistence of spontaneous magnetization of a ferromagnetic system to the random inclusion of antiferromagnetic interactions is investigated. After examing the static properties of the quenched version (in respect to the random antiferromagnetic interactions) of the model, the persistence of the magnetization is analysed also in the annealed approximation, and the difference in the results are discussed

Utilização de minhocas na estabilização de resíduos orgânicos: Vermicompostagem.

Criação das minhocas.bitstream/CNPAB-2010/27133/1/cot008.pdfed. rev. mod