Despite improved endotracheal tube designs, aspiration remains a cause of pulmonary complications. This in vitro study evaluates the efficacy of positive end-expiratory pressure (PEEP) in reducing the incidence of seepage around endotracheal tubes during mechanical (MV) and spontaneous ventilation (SV). Two transparent plastic "tracheas" with cuffed and uncuffed endotracheal tubes simulated adu...

This paper presents the results of a field investigation in the unsaturated, fractured welded tuff within the Exploratory Studies Facility (ESF) at Yucca Mountain, NV. This investigation included a series of tests during which tracer-laced water was released into a high-permeability zone within a horizontal injection borehole. The tracer concentration was monitored in the seepage collected in a...

We investigate erosion patterns observed in a horizontal granular bed resulting from seepage of water motivated by observation of beach rills and channel growth in larger scale land forms. Our experimental apparatus consists of a wide rectangular box filled with glass beads with a narrow opening in one of the side walls from which eroded grains can exit. Quantitative data on the shape of the pa...

A model has been developed to predict concentrations of the faecal bacteria indicator E. coli in streams draining grazed hill-country in New Zealand. The long-term aim of the modelling is to assess effects of land management upon faecal contamination and, in the short term, to provide a framework for field-based research. A daily record of grazing livestock is used to estimate E. coli inputs to...

In order to solve the adverse effect that lining of high groundwater level channels is prone damage when subjected heavy rainfall, response law internal structural state under different rainfall conditions was studied. Based on non-seepage seepage theory, pressure (total water head) in tunnel four types analyzed and The results show most unfavorable for structure safety are frontal uniform type...

We examine a dynamic model for the disruption of information flow in hierarchical social networks by considering the vertex-pursuit game Seepage played in directed acyclic graphs (DAGs). In Seepage, agents attempt to block the movement of an intruder who moves downward from the source node to a sink. We propose a generalized stochastic model for DAGs with given expected total degree sequence. S...

Loss of nitrate from agricultural lands to surface waters is an important issue, especially in areas that are extensively tile drained. To reduce these losses, a wide range of in-field and edge-of-field practices have been proposed, including constructed wetlands. We re-evaluated constructed wetlands established in 1994 that were previously studied for their effectiveness in removing nitrate fr...

A novel discrete singular convolution (DSC)  formulation  is  presented for the seepage analysis in irregular geometric porous media. The DSC is a new promising numerical approach which has been recently applied to solve several engineering problems. For a medium with regular geometry, realizing of the DSC for the seepage analysis is straight forward. But DSC implementation for a medium with ir...