Wave propagation in anisotropic medium due to an oscillatory point source with application to unidirectional composites

The far-field displacements in an infinite transversely isotropic elastic medium subjected to an oscillatory concentrated force are derived. The concepts of velocity surface, slowness surface and wave surface are used to describe the geometry of the wave propagation process. It is shown that the decay of the wave amplitudes depends not only on the distance from the source (as in isotropic media) but also depends on the direction of the point of interest from the source. As an example, the displacement field is computed for a laboratory fabricated unidirectional fiberglass epoxy composite. The solution for the displacements is expressed as an amplitude distribution and is presented in polar diagrams. This analysis has potential usefulness in the acoustic emission (AE) and ultrasonic nondestructive evaluation of composite materials. For example, the transient localized disturbances which are generally associated with AE sources can be modeled via this analysis. In which case, knowledge of the displacement field which arrives at a receiving transducer allows inferences regarding the strength and orientation of the source, and consequently perhaps the degree of damage within the composite

Linear LL-positive sets and their polar subspaces

In this paper, we define a Banach SNL space to be a Banach space with a certain kind of linear map from it into its dual, and we develop the theory of linear $L$-positive subsets of Banach SNL spaces with Banach SNL dual spaces. We use this theory to give simplified proofs of some recent results of Bauschke, Borwein, Wang and Yao, and also of the classical Brezis-Browder theorem.Comment: 11 pages. Notational changes since version

Postanesthetic Severe Oral Angioedema in Patient's Taking Angiotensin-Converting Enzyme Inhibitor

Angiotensin-converting enzyme (ACE) inhibitors are the leading cause of a drug-induced angioedema. This occurrence is frequently underdiagnosed, but its relapse can be life-threatening. The authors' intention in reporting this clinical case is to sound a warning about reviewing attitudes and surveillance to try to improve patient perioperative safety

O mini-cavalo (Equus caballus) puruca da ilha de Marajó - Brasil.

O mini-cavalo Puruca em conservação no BAGAM - Banco de Germoplasma Animal da Amazônia Oriental constitui uma pequena população, sendo resultado do cruzamento do cavalo Marajoara com o pônei da raça francesa ?Shetland?, que foi selecionado até atingir a altura padrão de 1,18m. A Associação Brasileira de Criadores da Raça Puruca ? ABCRP cita que a raça possui inúmeras características morfológicas que o tornam um grupo diferenciado. Os animais são criados em Salvaterra, ilha de Marajó, PA. Os descritores estudados são: Altura da Cernelha (AC), Altura do Dorso (AD), Altura da Garupa (AG), Altura de Costados (ACo), Comprimento da Cabeça (CCa), Comprimento do Pescoço (CP), Comprimento Dorso-Lombo (CDL), Comprimento da Garupa (CG), Comprimento da Espádua (CE), Comprimento do Corpo (CC), Largura da Cabeça (LC), Largura do Peito (LP), Largura das Ancas (LA), Perímetro do Tórax (PT) e Perímetro da Canela (PC), além dos pesos nas idades padrões. A raça, com base em marcadores microssatélites, é uma variedade da raça Marajoara, em função de cruzamentos entre os dois grupos genéticos e seleção para o menor porte. Este trabalho apresenta resultados parciais dos principais descritores, além de avaliar o comportamento e o desempenho da raça em conservação