University of Oklahoma

About: University of Oklahoma is a education organization based out in Norman, Oklahoma, United States. It is known for research contribution in the topics: Population & Radar. The organization has 25269 authors who have published 52609 publications receiving 1821706 citations. The organization is also known as: OU & Oklahoma University.

Lattice Boltzmann pore-scale model for multicomponent reactive transport in porous media

Abstract: [1] In this work, a multicomponent lattice Boltzmann (LB) model is presented for simulating reactive transport in porous media at the pore scale. In the model, a set of distribution functions is introduced to simulate fluid flow and solute transport. The model takes into account advection, diffusion, homogeneous reactions among multiple aqueous species, and heterogeneous reactions between the aqueous solution and minerals, as well as changes in solid and pore geometry. Homogeneous reactions are described through local equilibrium mass action relations. Mineral reactions are treated kinetically through boundary conditions at the mineral surface. The LB equation for flow recovers the correct pore-scale continuity and Navier-Stokes equations. The LB equations for solute transport are modified to recover advection-diffusion equations for total concentrations at the pore scale. The model is applied to a hypothetical three-component system with two aqueous complexes and two mineral reactions in a simple pore geometry. The effects of advection, diffusion, reaction rate constants, equilibrium constants of both homogeneous and heterogeneous reactions, and chemical compositions on mineral alteration of the porous medium and solute concentration are analyzed.

Adjuvant Chemotherapy plus Radiation for Locally Advanced Endometrial Cancer

Abstract: Background Stage III or IVA endometrial cancer carries a significant risk of systemic and locoregional recurrence. Methods In this randomized phase 3 trial, we tested whether 6 months of p...

Numerical Simulation of Thunderstorm Outflow Dynamics. Part I: Outflow Sensitivity Experiments and Turbulence Dynamics

Abstract: In this first paper of a two-part series, a two-dimensional numerical model is developed and used to investigate the dynamics of thunderstorm outflows. By focusing only on the outflow and using essentially inviscid equations and high spatial resolution, we are able to explicitly represent important physical processes such as turbulent mixing. To simplify interpretation of the results, the model atmosphere used in all experiments is calm and dry adiabatic. This approach allows us to establish basic characteristics of modeled outflows in simple physical settings, and provides a foundation for future studies using more realistic environments. All simulated outflows are initialized by prescribing a (controlled) horizontal flux of cold air into the model domain through a lateral boundary. In a series of sensitivity tests, we examine three parameters of the cold air source region: 1) the vertical temperature deficit profile, 2) the magnitude of the temperature deficit, and 3) the cold-air depth. By hol...

History and the global ecology of squamate reptiles

Abstract: The structure of communities may be largely a result of evolutionary changes that occurred many millions of years ago. We explore the historical ecology of squamates (lizards and snakes), iden- tify historically derived differences among clades, and examine how this history has affected present-day squamate assemblages globally. A dietary shift occurred in the evolutionary history of squamates. Iguanian diets contain large proportions of ants, other hymenop- terans, and beetles, whereas these are minor prey in scleroglossan lizards. A preponderance of termites, grasshoppers, spiders, and in- sect larvae in their diets suggests that scleroglossan lizards harvest higher energy prey or avoid prey containing noxious chemicals. The success of this dietary shift is suggested by dominance of sclero- glossans in lizard assemblages throughout the world. One sclero- glossan clade, Autarchoglossa, combined an advanced vomeronasal chemosensory system with jaw prehension and increased activity levels. We suggest these traits provided them a competitive advantage during the day in terrestrial habitats. Iguanians and gekkotans shifted to elevated microhabitats historically, and gekkotans shifted activity to nighttime. These historically derived niche differences are apparent in extant lizard assemblages and account for some observed structure. These patterns occur in a variety of habitats at both regional and local levels throughout the world.