Bubble rise in molten glasses and silicate melts during heating and cooling cycles.

The Hadamard-Rybczynski equation describes the steady-state buoyant rise velocity of an unconfined spherical bubble in a viscous liquid. This solution has been experimentally validated for the case where the liquid viscosity is held constant. Here, we extend this result for non-isothermal conditions, by developing a solution for bubble position in which we account for the time-dependent liquid viscosity, liquid and gas densities, and bubble radius.

Impact evaluation of instream bar management using morphodynamic modelling.

The Bow River's 2013 flood was the costliest natural disaster in the City of Calgary's history. Flood-induced bar growth and subsequent riparian vegetation colonization at many locations has constricted the river channel, which increases flood risk. Although bar removal has been widely employed as a flood mitigation strategy, its effectiveness and associated impacts are still uncertain.

Impacts of Channel Morphodynamics on Fish Habitat Utilization.

It is reasonable to expect that hydro-morphodynamic processes in fluvial systems can affect fish habitat availability, but the impacts of morphological changes in fluvial systems on fish habitat are not well studied. Herein we investigate the impact of morphological development of a cohesive meandering stream on the quality of fish habitat available for juvenile yellow perch (Perca flavescens) and white sucker (Catostomus commersonii). A three-dimensional (3D) morphodynamic model was first developed to simulate the hydro-morphodynamics of the study creek.

The impact of channel capture on estuarine hydro-morphodynamics and water quality in the Amazon delta.

Due to progressive erosion of the new Urucurituba Channel, the Amazon River has recently captured almost all discharge from the lower Araguari River (Amapá-AP, Brazil), which previously flowed directly to the Atlantic Ocean. These recent geomorphological changes have caused strong impacts on the landscape and hydrodynamic patterns near the Araguari River mouth, especially the alteration of the riverine drainage system and its water quality. Landsat images were used to assess the estuarine landscape morphodynamic, particularly the expansion of the Urucurituba Channel, 80km from the Araguari River mouth, chronicling its connection to the Amazon River.

Hypoxic conditions in stormwater retention ponds: potential for hydrogen sulfide emission.

Improper design and maintenance of stormwater ponds (SWPs) may lead to hypoxic conditions, poor water quality and the production of hydrogen sulfide (HS). The objective of this study is to develop a comprehensive understanding of hypoxic conditions of SWPs, with a focus on the potential for HS production and emission. This study was conducted at two retention SWPs in Ottawa, Canada; a problematic pond with the propensity for HS emission and a reference pond that did not demonstrate HS emission.

Reducing Periconceptional Methylmercury Exposure: Cost-Utility Analysis for a Proposed Screening Program for Women Planning a Pregnancy in Ontario, Canada.

Background: The assessment of neurodevelopmental effects in children associated with prenatal methylmercury exposure, from contaminated fish and seafood in the maternal diet, has recently been strengthened by adjustment for the negative confounding resulting from co-exposure to beneficial polyunsaturated fatty acids (PUFAs).

Objectives: We aimed to determine the cost-effectiveness of a periconceptional screening program of blood mercury concentration for women planning to become pregnant in Ontario, Canada. Fish intake recommendations would be provided for those found to have blood mercury levels above the intervention threshold.

Flow in bedrock canyons.

Bedrock erosion in rivers sets the pace of landscape evolution, influences the evolution of orogens and determines the size, shape and relief of mountains. A variety of models link fluid flow and sediment transport processes to bedrock incision in canyons. The model components that represent sediment transport processes are increasingly well developed.

Stochastic calibration of riverine water quality models.

Though commonly used, the suitability of deterministic calibration criteria for stochastic model calibration and uncertainty analysis is unclear. The purpose of this paper is to examine the suitability, relative benefits, and substantial disadvantages of "deterministic-optimization" approaches, such as root mean square error (RMSE), in stochastic contexts. Three alternate calibration strategies that are suitable for stochastic modeling of water quality under uncertainty are proposed and then demonstrated.