In this work, we present a numerical method for solving the diffraction of transient elastic waves by cracks of arbitrary shapes in complex media, with Signorini’s boundary conditions on the crack. We use a fictitious domain method based on a mixed displacement–stress formulation for elastodynamics. We propose an off-centered time discretisation scheme for enforcing the stability.

Introduction: Some snails play an important role in the transmission of helminthes, mainly trematodes of medical and veterinary importance. There seems to be no information on the freshwater snails of Gahar Lake in Lorestan province of Iran. The present study aimed to identify medically important snails of this lake. Methods: Samples were collected from ten localities around Gahar Lake in April...

conclusions the reason for difference in the detected snail genera in sampling sites may be due to various physicochemical factors. according to the current study, medically important snails exist in miangran lake and they could be a source of trematode infections for the local people. controlling measures after comprehensive studies should be applied. background some freshwater snails are acti...

—We provide the first description of the eggs, breeding biology, and natural history of the Ochre-breasted Brush Finch (Atlapetes semirufus). We found 37 nests over four breeding seasons (2004– 2007) in Yacambú National Park, Venezuela. Nesting activity started in late April and continued until early June suggesting single-brooded behavior despite a typical tropical clutch size of two eggs (x̄ 1...

Pale-headed Brush-finch Atlapetes pallidiceps is a restricted-range species that is threatened with extinction due to habitat loss. The total population of 60–80 individuals achieved a reproductive output of only 0.74 young per breeding pair in 2002. Brood parasitism by Shiny Cowbird Molothrus bonariensis was a major factor reducing breeding success, affecting 38.5% of broods. Parasitism rates ...

introduction: some snails play an important role in the transmission of helminthes, mainly trematodes of medical and veterinary importance. there seems to be no information on the freshwater snails of gahar lake in lorestan province of iran. the present study aimed to identify medically important snails of this lake. methods: samples were collected from ten localities around gahar lake in april...

We examine the evolution of mesic forest ecosystems in the Pacific Northwest of North America using a statistical phylogeography approach in four animal and two plant lineages. Three a priori hypotheses, which explain the disjunction in the mesic forest ecosystem with either recent dispersal or ancient vicariance, are tested with phylogenetic and coalescent methods. We find strong support in th...