Relaxation-chaos phenomena in celestial mechanics. I. On wisdom's model for the 3/1 kirkwood gap

Sudden eccentricity increases of asteroidal motion in 3/1 resonance with Jupiter were discovered and explained by J. Wisdom through the occurrence of jumps in the action corresponding to the critical angle (resonant combination of the mean motions). We pursue some aspects of this mechanism, which could be termed relaxation-chaos: that is, an unconventional form of homoclinic behavior arising in perturbed integrable Hamiltonian systems for which the KAM theorem hypothesis do not hold. © 1987.

Kinetic properties of de-repressible alkaline phosphatase (EC 3.1.3.1) from Neurospora crassa

De-repressible alkaline phosphatase from N. crassa shows inhibition by PNP-P and a hyperbolic mixed-type inhibition by Pi. Both increasing concentrations of Pi and decreases in assay pH abolished inhibition by the substrate. Also, Pi promoted polymerization of the enzyme molecule, whose effect may account for the inhibitory behaviour shown by the enzyme in the presence of low Pi concentrations. © 1991 Rapid Communications of Oxford Ltd.

Soft superweak CP violation in a 3-3-1 model

We show that it is possible to implement soft superweak CP violation in the context of a 3-3-1 model with only three triplets. All CP violation effects come from the exchange of singly and doubly charged scalars. We consider the implication of this mechanism in the quark and lepton sectors. In particular it is shown that, in this model, as in most of those which incorporate scalar mediated CP violation, it is possible to have large electric dipole moments for the muon and the tau lepton while keeping small those of the electron and neutron. The CKM mixing matrix is real at the tree level but gets a phase at the 1-up loop level. ©1999 The American Physical Society.

Spontaneous breaking of a global symmetry in a 3-3-1 model

In a 3-3-1 model in which the lepton masses arise from a scalar sextet it is possible to break spontaneously a global symmetry which implies in a pseudoscalar Majoron-like Goldstone boson. This Majoron does not mix with any other scalar fields and for this reason it does not couple, at the tree level, to either the charged leptons or to the quarks. Moreover, its interaction with neutrinos is diagonal. We also argue that there is a set of parameters in which the model can be consistent with the invisible Z0 width and that heavy neutrinos can decay sufficiently rapid by Majoron emission, having a lifetime shorter than the age of the universe. ©1999 The American Physical Society.

Soft supcrweak CP violation in a 3-3-1 model

We show that it is possible to implement soft superweak CP violation in the context of a 3-3-1 model with only three triplets. All CP violation effects come from the exchange of singly and doubly charged scalars. We consider the implication of this mechanism in the quark and lepton sectors. In particular it is shown that, in this model, as in most of those which incorporate scalar mediated CP violation, it is possible to have large electric dioole moments for the muon and the tau lepton while keeping small those of the electron and neutron. The CKM mixing matrix is real at the tree level but gets a phase at the 1-up loop level. ©1999 The American Physical Society.

Remark on the muonium to antimuonium conversion in a 3-3-1 model

Here we analyze the relation between the search for muonium to antimuonium conversion and the 3-3-1 model with doubly charged bileptons. We show that the constraint on the mass of the vector bilepton obtained by experimental data can be evaded even in the minimal version of the model since there are other contributions to that conversion. We also discuss the condition for which the experimental data constraint is valid. ©2000 The American Physical Society.

Exact time dependent Hopf solitons in 3+1 dimensions

We construct an infinite number of exact time dependent soliton solutions, carrying non-trivial Hopf topological charges, in a 3+1 dimensional Lorentz invariant theory with target space S2. The construction is based on an ansatz which explores the invariance of the model under the conformal group SO(4,2) and the infinite dimensional group of area preserving diffeomorphisms of S2. The model is a rare example of an integrable theory in four dimensions, and the solitons may play a role in the low energy limit of gauge theories. © SISSA 2006.

MTA-induced neutrophil recruitment: a mechanism dependent on IL-1β, MIP-2, and LTB4

Objective: The objective of this study was to investigate the mediators and the resident peritoneal cells involved in the neutrophil migration (NM) induced by mineral trioxide aggregate (MTA) in mice. Study design: MTA (25 mg/cavity) was injected into normal and pretreated peritoneal cavities (PC) with indomethacin (IND), dexamethasone (DEX), BWA4C, U75302, antimacrophage inflammatory protein-2 (MIP-2), and anti-interleukin-1β (IL-1β) antibodies and the NM was determined. The role of macrophage (MO) and mast cells (MAST) was determined by administration of thioglycollate 3% or 48/80 compound, respectively. The concentration of IL-1β and MIP-2 exudates was measured by ELISA. Results: MTA induced dose- and time-dependent NM into mice PC, with the participation of MO and MAST. NM was inhibited by DEX, BWA4C, and U75302, as well as anti-MIP-2 and anti-IL-1β antibodies. In the exudates, IL-1β and MIP-2 were detected. Conclusions: This study suggests that MTA induces NM via a mechanism dependent on MAST and MO mediated by IL-1β, MIP-2, and LTB4. © 2008 Mosby, Inc. All rights reserved.

Mild cognitive impairment (part 1): Clinical characteristics and predictors of dementia

Objective: To critically review and evaluate existing knowledge on the conceptual limits and clinical usefulness of the diagnosis of mild cognitive impairment (MCI) and the neuropsychological assessment and short- and long-term prognosis thereof. Methods: We conducted a systematic search of the PubMed and Web of Science electronic databases, limited to articles published in English between 1999 and 2012. Based on the search terms mild cognitive impairment or MCI and epidemiology or diagnosis, we retrieved 1,698 articles, of which 248 were critically eligible (cross-sectional and longitudinal studies); the abstracts of the remaining 1,450 articles were also reviewed. Results: A critical review on the MCI construct is provided, including conceptual and diagnostic aspects; epidemiological relevance; clinical assessment; prognosis; and outcome. The distinct definitions of cognitive impairment, MCI included, yield clinically heterogeneous groups of individuals. Those who will eventually progress to dementia may present with symptoms consistent with the definition of MCI; conversely, individuals with MCI may remain stable or return to normal cognitive function. Conclusion: On clinical grounds, the cross-sectional diagnosis of MCI has limited prognostic relevance. The characterization of persistent and/or progressive cognitive deficits over time is a better approach for identification of cases at the pre-dementia stages, particularly if these cognitive abnormalities are consistent with the natural history of incipient Alzheimer's disease. © 2013 Associação Brasileira de Psiquiatria.

Momento de dipolo elétrico do nêutron no modelo 3-3-1

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Flavor-changing neutral currents in the minimal 3-3-1 model revisited

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for the Higgs boson H-2(0) at LHC in 3-3-1 model

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Do catálogo impresso ao cátalogo on-line: algumas considerações e desafios ao bibliotecário

In relation to the changes that mark the trajectory of libraries catalogs, this paper aims to describe the challenges that go beyond the current status of librarians, in relation to use of the on-line catalog as the main tool storage and retrieval of documentary information. Using literature specialized is intended to contribute to the discussion of the topic, in order to understand the challenges and prospects of using this important tool for search and information retrieval.

Automatic Indexing and Information Visualization: A Study Based on Paraconsistent Logic

This paper reports a research to evaluate the potential and the effects of use of annotated Paraconsistent logic in automatic indexing. This logic attempts to deal with contradictions, concerned with studying and developing inconsistency-tolerant systems of logic. This logic, being flexible and containing logical states that go beyond the dichotomies yes and no, permits to advance the hypothesis that the results of indexing could be better than those obtained by traditional methods. Interactions between different disciplines, as information retrieval, automatic indexing, information visualization, and nonclassical logics were considered in this research. From the methodological point of view, an algorithm for treatment of uncertainty and imprecision, developed under the Paraconsistent logic, was used to modify the values of the weights assigned to indexing terms of the text collections. The tests were performed on an information visualization system named Projection Explorer (PEx), created at Institute of Mathematics and Computer Science (ICMC - USP Sao Carlos), with available source code. PEx uses traditional vector space model to represent documents of a collection. The results were evaluated by criteria built in the information visualization system itself, and demonstrated measurable gains in the quality of the displays, confirming the hypothesis that the use of the para-analyser under the conditions of the experiment has the ability to generate more effective clusters of similar documents. This is a point that draws attention, since the constitution of more significant clusters can be used to enhance information indexing and retrieval. It can be argued that the adoption of non-dichotomous (non-exclusive) parameters provides new possibilities to relate similar information.

Efeito do 1,3/1,6 beta-glucano no sistema imune de cadelas submetidas a ovário-histerectomia

Pós-graduação em Medicina Veterinária - FCAV