We describe statistical properties of the visual normal flow. These are used to model space-time texture, such as waterfalls, an open problem in visual motion analysis. The normal flow is perpendicular to edges. It is the only component of the image velocity that can be locally computed, so that it is simple to implement. We analysed the statistical representation of the normal flow magnitude f...

Athyrium haleakalae K.R. Wood & W.L. Wagner (Athyriaceae), a small lithophytic fern from East Maui, Hawaiian Islands, is described and illustrated. Notes on its distribution, ecology, and conservation status are also presented. The new species appears to be an obligate rheophyte, preferring sites of fast moving water along concave walls of streams and waterfalls. Athyrium haleakalae differs fro...

The genus Vestalenula is the most species rich in the putative ancient asexual ostracod Family Darwinulidae. Several new Recent species were described from various continents, mostly based on carapace shape and structure. These species were found in a variety of aquatic and (semi-) terrestrial habitats, including springs, streams, interstitial waters, leaf litter in forests and in splash zones ...

We develop a method that o¤ers consistent and computationally e¢ cient credit risk analysis of cash‡ow CDO structures. The proposal makes use of simple portfolio models that admit semi-analytic representations of the loss distribution, combined with detailed and fast calculations of realistic interest and principal cash‡ow waterfalls. We de…ne in this context and study credit tranche risk measu...

Ranid frogs of the genus Amolops occur in Southeast Asia and are typically found near waterfalls. Their phylogenetic relationships have not been resolved. We include 2,213 aligned nucleotide sites of the 12S, 16S and tRNAval gene regions of the mitochondrial DNA genome from 43 individuals of Chinese and Vietnamese Amolops, Huia, Hylarana, Meristogenys, Odorrana and Rana. The outgroup species we...

Late Quaternary separation of Britain from mainland Europe is considered to be a consequence of spillover of a large proglacial lake in the Southern North Sea basin. Lake spillover is inferred to have caused breaching of a rock ridge at the Dover Strait, although this hypothesis remains untested. Here we show that opening of the Strait involved at least two major episodes of erosion. Sub-bottom...

A suite of recently developed statistical methods to estimate the abundance and density unmarked animals from camera traps require accurate estimates area sampled by each camera. Although viewshed is fundamental achieving estimates, there are no established guidelines for collecting this information in field. Furthermore, while complexities detection process motion sensor photography generally ...