Classification of normal swallowing and oropharyngeal dysphagia using wavelet

Oropharyngeal dysphagia is characterized by any alteration in swallowing dynamics which may lead to malnutrition and aspiration pneumonia. Early diagnosis is crucial for the prognosis of patients with dysphagia, and the best method for swallowing dynamics assessment is swallowing videofluoroscopy, an exam performed with X-rays. Because it exposes patients to radiation, videofluoroscopy should not be performed frequently nor should it be prolonged. This study presents a non-invasive method for the pre-diagnosis of dysphagia based on the analysis of the swallowing acoustics, where the discrete wavelet transform plays an important role to increase sensitivity and specificity in the identification of dysphagic patients. (C) 2008 Elsevier B.V. All rights reserved.

Crystallographic and spectroscopic characterization of a molecular hinge: Conformational changes in bothropstoxin I, a dimeric Lys49 phospholipase A2 homologue

Bothropstoxin I(BthTX-I) from the venom of Bothrops jararacussu is a myotoxic phospholipase A2 (PLA2) homologue which, although catalytically inactive due to an Asp49-->Lys substitution, disrupts the integrity of lipid membranes by a Ca2+-independent mechanism, the crystal structures of two dimeric farms of BthLTX-I which diffract X-rays eo resolutions of 3.1 and 2.1 Angstrom have been determined, the monomers in both structures are related by an almost perfect twofold axis of rotation and the dimer interfaces are defined by contacts between the N-terminal alpha-helical regions and the tips of the beta-wings of partner monomers. Significant differences in the relative orientation of the monomers in the two crystal forms results in open and closed dimer conformations, Spectroscopic Investigations of BthTX-I in solution have correlated these conformational differences with changes in the intrinsic fluorescence emission of the single tryptophan residues located at the dimer interface, the possible relevance of this structural transition in the Ca2+-independent membrane damaging activity is discussed. (C) 1998 Wiley-Liss, Inc.

Redescription of Astyanax goyacensis Eigenmann, 1908 (Ostariophysi: Characiformes: Characidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Hasemania piatan, a new characid species (Characiformes: Characidae) from headwaters of Rio de Contas, Bahia, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Astyanax ajuricaba: a new species from the Amazon basin in Brazil (Characiformes: Characidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Descrição de Astyanax argyrimarginatus sp. n. (Characiformes, Characidae) procedente da bacia do Rio Araguaia, Brasil

Descreve-se uma espécie nova para o gênero Astyanax Baird & Girard. A. argyrimarginatus procede da bacia do Rio Araguaia, Brasil. Esta espécie pode ser identificada por possuir uma mancha umeral negra horizontalmente ovalada, uma mancha negra no pedúnculo caudal, que se estende à extremidade dos raios caudais medianos, duas barras verticais castanho-escuras na região umeral e uma faixa lateral negra conspícua, bordeada por uma estreita faixa prateada. São discutidos outros caracteres que distinguem a espécie nova das demais espécies do gênero Astyanax portadoras de uma mancha umeral horizontalmente ovalada.

Hyphessobrycon rutiliflavidus n. sp., a new characid fish from the upper rio Paraguai, State of Mato Grosso, Brazil (Characiformes : Characidae)

Hyphessobrycon rutiliflavidus, new species, is described from the upper rio Paraguai in Cuiaba, State of Mato Grosso, Brazil. The new species differs from all other congeners by the following combination of characters: black humeral spot, slightly diffuse at its tips, and caudal-peduncle blotch present; midlateral body stripe conspicuous in its posteriormost portion, extending to the tips of the middle caudal rays; anal fin with iii, 15 to iv, 19 rays (mode iv, 17); upper jaw length, 42.3 to 49.5% of the head length; maxilla with 2-5 teeth (mode 3); all the fins of males reddish-orange and of females yellowish.

A new Hemigrammus Gill from upper rio Parana system, Southeastern Brazil (Characiformes : Characidae)

Hemigrammus parana is described from the upper rio Parana system, in the area of influence of the Ilha Solteira reservoir in states of Mato Grosso do Sul, Minas Gerais and São Paulo, southeastern Brazil. The new species differs from all congeners by the combination of the following characters: absence of humeral spot; presence of a roughly triangular or rectangular conspicuous black caudal spot, extending from base to tip of middle caudal-fin rays, its greatest depth at base of caudal-fin rays; and anal-fin rays iii-iv, 18-23.

A new species of Moenkhausia from the rio Amazonas and rio Orinoco basins (Characiformes: Characidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bounds on direct couplings of superheavy metastable particles to the inflaton field from ultra high energy cosmic ray events

Top-down models for the origin of ultra high energy cosmic rays (UHECR's) propose that these events are the decay products of relic superheavy metastable particles, usually called X particles. These particles can be produced in the reheating period following the inflationary epoch of the early Universe. We obtain constraints on some parameters such as the lifetime and direct couplings of the X-particle to the inflaton field from the requirement that they are responsible for the observed UHECR flux.

Optical black holes in moving dielectrics

We study the optical paths of the light rays propagating inside a nonlinear moving dielectric medium. For rapidly moving dielectrics we show the existence of a distinguished surface which resembles, as far as the light propagation is concerned, the event horizon of a black hole. Our analysis clarifies the physical conditions under which electromagnetic analogues of gravitational black holes can eventually be obtained in laboratory.

Connection between UHECR's and supermassive relic particles

One of the models proposed for the origin of ultra high energy cosmic rays (UHECR's) suggests that these events are the decay products of relic superheavy metastable particles, which we call S particles. These particles can be produced in the reheating period following the inflationary epoch of the early Universe. We study this possibility and obtain constraints on some parameters such as the lifetime and direct couplings of the X-particle to the inflaton field from the requirement that they are responsible for the observed UHECR flux.

Higher-derivative theory of (2+1)-dimensional gravity

Higher-derivative gravity in 2 + 1 dimensions is considered. The general solution of the linearized field equations in a three-dimensional version of the Teyssandier gauge is obtained, and from that the solution for a static pointlike source is found. The deflection of light rays is also analysed. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Light deflection and quadratic gravity

We study the bending of light caused by a static gravitational field generated by a localized material source in the context of quadratic gravity. Our calculation shows that for light rays passing close to the Sun the deflection Phi lies in the interval 0 < < 1.75. A tree-level approach to the same issue tells us that the vacuum concerning quadratic gravity is a dispersive medium. Nom Phi is energy dependent and ranges from 0(+) to 1.75(-) arcsec.

Confusing the extragalactic neutrino flux limit with a neutrino propagation limit

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)