Oligosarcus amome is described from tributaries of the arroyo Yabotí-Guazú, río Uruguay basin, Misiones Province, Argentina. This new species can be distinguished from all its congeners by the following combination of characters: presence of two conspicuous series of teeth on premaxilla bearing pentacuspidate teeth in the outer series. Oligosarcus amome is the sister taxon of all remaining anal...

Chylopericardium is a rare disorder that may be primary (idiopathic) or secondary to injury of the thoracic duct or thymus gland. Pediatric cardiac operations are more commonly related to this complication because thymus gland is very active in this population and atrophies in the adult patients. We present a case of chylopericardium after mitral valve repair for rheumatic disease, due to thymu...

the behavior of suspended sediment during flood events is not only a function of energy conditions, i.e. sediment is stored at low flow and transported under high flow conditions, but also is related to the variations in sediment supply and sediment depletion. these changes in sediment availability result in so-called hysteresis effects. therefore, hysteresis pattern analysis is of great import...