Sodium Flux during Haemodialysis

Dialysis is aimed at the removal of charged ionic species in the blood that arise from complications in kidney disease. Although the process for the removal of urea and other unwanted charged species is understood, the effect of this removal on the net sodium concentration in the blood after treatment is not clear. In this report, we focus on formulating a fundamentally-based model to address this question. We consider the formulation near the membrane at the pore scale in order to determine effective jump conditions in ionic concentrations, electric potential and flow rate based on the membrane properties, and in order to determine whether electroneutrality holds within the pore. Secondly, we consider the local blood-cell concentration within one of the fibres and how this varies axially within the dialysis cartridge. Lastly, we consider a simple one-dimensional model of the charged species problem and find that advection transport through the membrane is important for sodium transport, but less pertinent for transport of other cation species

CARIBBEAN DEMAND OF U.S. AND REST-OF-THE-WORLD STARCHY FOOD (WHEAT, RICE, CORN, AND FRESH POTATOES): A RESTRICTED SOURCE DIFFERENTIATED ALMOST IDEAL DEMAND SYSTEM

This study provides elasticity estimates of the Caribbean demand for U. S. and Rest-of-the-World starchy foods (unmilled wheat and flour, rice, corn and fresh potatoes) using the Restricted Source Differentiated Almost Ideal Demand System (RSDAIDS) model. Caribbean per capita import demand curves for U.S. and Rest-of-the-World (ROW) are own-price unitary elastic for U. S. wheat, and own-price inelastic for U.S. rice and ROW wheat and rice. The implication is that reductions by any means in U. S. or ROW export prices of wheat and rice will increase U.S. or ROW exported quantities in the Caribbean, while at the same time securing food security through import quantity in the Caribbean. Wheat is not produced in the Caribbean. U. S. wheat price policy oriented toward a reduction in the export price of wheat to the Caribbean may increase the U. S. wheat market share in the Caribbean. For wheat and rice, no competition across source exists. Instead, there exists a complementarity relationship across source for each of the two products. In other words, the Caribbean distinguishes between the wheat or rice coming from the U. S. and the wheat or rice coming from the Rest-of-the-World.Caribbean demand, elasticity estimates, food security, price policies, Restricted Source Differentiated Almost Ideal Demand System (RSDAIDS), starchy food, Food Consumption/Nutrition/Food Safety,

Gravitational waves in preheating

We study the evolution of gravitational waves through the preheating era that follows inflation. The oscillating inflaton drives parametric resonant growth of scalar field fluctuations, and although super-Hubble tensor modes are not strongly amplified, they do carry an imprint of preheating. This is clearly seen in the Weyl tensor, which provides a covariant description of gravitational waves.Comment: 8 pages, 8 figures, Revte

USING MIXED-INTEGER PROGRAMMING TO DETERMINE THE POTENTIAL FOR FLOUR-MILLING INDUSTRY EXPANSION

As in most predominantly agricultural states, agricultural producers in Oklahoma have expressed an interest in value-added processing opportunities. While Oklahoma produces mostly hard red winter wheat, most Oklahoma bakers require predominantly soft wheat flour for their products, almost all of which is purchased from out-of-state suppliers. An economic engineering-based, mixed-integer programming model was used to determine the optimal number, size, and location of additional flour mills in Oklahoma to capture this excess flour demand. The results suggest that additional mills are potentially justified and that the potential for additional milling will increase if Oklahoma soft wheat production increases.Agribusiness,

FEASIBILITY OF AN OKLAHOMA FRESH GREENS AND COWPEAS PACKING COOPERATIVE

Oklahoma's green producers are not benefiting from a growing fresh market. In order to seize the opportunities offered by the growing fresh market for leafy greens, investment in packing facilities have been evaluated. To make use of these facilities during summer months, the addition of a cowpea shelling enterprise is considered. A business plan for a new generation cooperative is estimated using an updated version of "The Packing Simulation Model" (PACKSIM) The business associates PACKSIM with @RISK®, to incorporate risks in the financial analysis.Agribusiness,

The high-lying 6^6Li levels at excitation energy around 21 MeV

The $^3$H+$^3$He cluster structure in $^6$Li was investigated by the $^3$H($\alpha$,$^3$H $^3$He)n kinematically complete experiment at the incident energy $E_\alpha$ = 67.2 MeV. We have observed two resonances at $E_x^*$ = 21.30 and 21.90 MeV which are consistent with the $^3$He($^3$H, $\gamma$)$^6$Li analysis in the Ajzenberg-Selove compilation. Our data are compared with the previous experimental data and the RGM and CSRGM calculations.Comment: 12 pages, 6 figures. Accepted for publication in J. Phys. Soc. Jp

Polarization states of polydomain epitaxial Pb(Zr1-xTix)O3 thin films and their dielectric properties

Ferroelectric and dielectric properties of polydomain (twinned) single-crystal Pb(Zr1-xTix)O3 thin films are described with the aid of a nonlinear thermodynamic theory, which has been developed recently for epitaxial ferroelectric films with dense laminar domain structures. For Pb(Zr1-xTix)O3 (PZT) films with compositions x = 0.9, 0.8, 0.7, 0.6, 0.5, and 0.4, the "misfit strain-temperature" phase diagrams are calculated and compared with each other. It is found that the equilibrium diagrams of PZT films with x > 0.7 are similar to the diagram of PbTiO3 films. They consist of only four different stability ranges, which correspond to the paraelectric phase, single-domain tetragonal ferroelectric phase, and two pseudo-tetragonal domain patterns. In contrast, at x = 0.4, 0.5, and 0.6, the equilibrium diagram displays a rich variety of stable polarization states, involving at least one monoclinic polydomain state. Using the developed phase diagrams, the mean out-of-plane polarization of a poled PZT film is calculated as a function of the misfit strain and composition. Theoretical results are compared with the measured remanent polarizations of PZT films grown on SrTiO3. Dependence of the out-of-plane dielectric response of PZT films on the misfit strain in the heterostructure is also reported.Comment: 23 pages, 4 figure