Factors of Political Party Competitiveness in Mississippi

This research project examines the relationship between urbanization and political party competitiveness in Mississippi. Using elections results from the 2011 and the 2015 Mississippi House of Representatives races, this project seeks to find if there is a relationship between urbanization and competitiveness in Mississippi, and if not, which factors do affect competitiveness. Previous research indicates that as an area urbanizes, its elections become more competitive among different political parties. However, this study finds that there is no clear correlation between urbanization and party competitiveness in Mississippi elections, and that other factors, including race, education, and geographic location, may have more influential roles

Electrohydrodynamic deformation and interaction of a pair of emulsion drops

The response of a pair of emulsion drops to the imposition of a uniform electric field is examined. The case studied is that of equal-sized drops whose line of centers is parallel to the axis of the applied field. A new boundary integral solution to the governing equations of the leaky dielectric model is developed; the formulation accounts for the electrostatic and hydrodynamic interactions between the drops, as well as their deformations. Numerical calculations show that, after an initial transient during which the drops primarily deform, the pair drift slowly together due to their electrostatic interactions

The onset of electrohydrodynamic instability in isoelectric focusing

The onset of electrohydrodynamic motion associated with the imposition of an electric field across a thin layer of liquid has been investigated for the case in which the electrical conductivity varies linearly over the depth of the layer. The variation of the conductivity is due to concentration gradients in the charge-carrying solutes and its spatio-temporal evolution is represented by a convective-diffusion equation. When the viscous relaxation time is long compared to the time for charge relaxation, the analysis reveals that the neutral stability curves for the layer can be characterized by three dimensionless parameters: Ra(sub e) is equivalent to d(epsilon)E(sup 2, sub 0) Delta sigma/mu K(sub eff) sigma(sub 0), an electrical Rayleigh number; delta sigma/sigma(sub 0), the relative conductivity increment; and alpha, the transverse wave number of the disturbance. Here d is the thickness, epsilon is the dielectric constant, and mu is the viscosity of layer, E(sub 0) is the applied field strength at the lower conductivity boundary, and K(sub eff) is an effective diffusivity associated with the Brownian motion of the charge-carrying solutes. With viscous-stress-free boundaries, at which the electrical conductivity and the normal component of the electric field are prescribed, the critical Ra(sub e) is 1.504 x 10(exp 4) at a critical transverse wave number of 1.97 when Delta sigma/sigma(sub 0) is 10. As Delta sigma/sigma(sub 0) increases, the critical Ra(sub e) increases and shifts to shorter wavelength disturbances; the critical imposed field strength, however, passes through a minimum because the lower-conductivity boundary exerts a considerable stabilizing influence in the presence of steep conductivity gradients. Similar trends were obtained for liquid layers with rigid boundaries

Electrohydrodynamic Interaction of a Pair of Spherical Drops

The axisymmetric electrohydrodynamic interaction between two spherical emulsion drops has been examined, using the leaky dielectric model to represent the constitutive behavior of the liquid phases. The results follow from the general solutions in bispherical coordinates to the Laplace equation for the electric potential and the Stokes equations for the velocity field. For drops of similar composition, the electrical interactions induced between the drops by the imposition of the electric field are always attractive, meaning they favor coalescence of the drop pair. The hydrodynamic interactions, however, are not always favorable and, indeed, are shown in certain circumstances to drive the drops apart

Spatiotemporal Modeling and Analysis of Disease Spread in Wildlife

Title from PDF of title page, viewed June 11, 2018Dissertation advisor: Majid Bani-YaghoubVitaIncludes bibliographical references (pages 113-120)Thesis (Ph.D.)--Department of Mathematics and Statistics and Department of Physics and Astronomy. University of Missouri--Kansas City, 2018Wildlife and wildlife diseases have been frequent topics in mathematical epidemiology. However, due to the complexity of real-world systems and the varying degree of randomness in the behavior of any one individual organism, it can be difficult to obtain reliable and accurate spatiotemporal results with any given methodology. In this work, we look at hemorrhagic diseases (HD) in white-tailed deer as a case study to explore statistical and mathematical modeling techniques for analyzing disease spread in wildlife. We concentrate on two modeling approaches to evaluate their capabilities and usefulness in predicting and analyzing the dynamics of wildlife diseases. Statistical modeling implemented with SaTScan enables us to identify significant clusters of disease activity, clusters that are significant with respect to geography or time or both. The spatial clusters of years 1980, 1988, 2007, 2012, and 2013 suggest patterns of outbreaks every six to eight years, with the next potential outbreak during 2018 - 2020. Using mathematical modeling with ordinary differential equations (ODE), we derive a model for the dynamics of the disease that includes the migration of the host. We also derive the basic reproduction number R₀ of this model to uncover the conditions that lead to an outbreak of the disease. In addition, we also apply several techniques using MATLAB to estimate the parameters of such a set of ODE which are useful when the available data set is limited in size.Introduction -- SaTScan and statistical analysis -- The HD model with migration effects -- Parameter estimates -- Model extensions, conclusions and future work -- Appendix A. Data summary -- Appendix B. MATLAB cod

Dielectrophoresis of charged colloidal suspensions

We present a theoretical study of dielectrophoretic (DEP) crossover spectrum of two polarizable particles under the action of a nonuniform AC electric field. For two approaching particles, the mutual polarization interaction yields a change in their respective dipole moments, and hence, in the DEP crossover spectrum. The induced polarization effects are captured by the multiple image method. Using spectral representation theory, an analytic expression for the DEP force is derived. We find that the mutual polarization effects can change the crossover frequency at which the DEP force changes sign. The results are found to be in agreement with recent experimental observation and as they go beyond the standard theory, they help to clarify the important question of the underlying polarization mechanisms

Electrophoretic mobility and molecular distribution studies of poly(amidoamine) dendrimers of defined charges

Generation 5 ethylenediamine (EDA)-cored poly(amidoamine) (PAMAM) dendrimers (E5, E denotes the EDA core and 5 the generation number) with different degrees of acetylation and carboxylation were synthesized and used as a model system to investigate the effect of charge and the influence of dendrimer surface modifications on electrophoretic mobility (EM) and molecular distribution. The surface-modified dendrimers were characterized by size-exclusion chromatography, 1 H NMR, MALDI-TOF-MS, PAGE, and CE. The focus of our study was to determine how EM changes as a function of particle charge and molecular mass, and how the molecular distribution changes due to surface modifications. We demonstrate that partially modified dendrimers have much broader migration peaks than those of fully surface functionalized or unmodified E5 dendrimers due to variations in the substitution of individual dendrimer surfaces. EM decreased nonlinearly with increases in surface acetylation for both PAMAM acetamides and PAMAM succinamic acids, indicating a complex migration activity in CE separations that is not solely due to charge/mass ratio changes. These studies provide new insights into dendrimer properties under an electric field, as well as into the characterization of dendrimer-based materials being developed for medical applications.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50647/1/1758_ftp.pd

There can be turbulence in microfluidics at low Reynolds number

Turbulence is commonly viewed as a type of macroflow, where the Reynolds number (Re) has to be sufficiently high. In microfluidics, when Re is below or on the order of 1 and fast mixing is required, so far only chaotic flow has been reported to enhance mixing based on previous publications since turbulence is believed not to be possible to generate in such a low Re microflow. There is even a lack of velocimeter that can measure turbulence in microchannels. In this work, we report a direct observation of the existence of turbulence in microfluidics with Re on the order of 1 in a pressure driven flow under electrokinetic forcing using a novel velocimeter having ultrahigh spatiotemporal resolution. The work could provide a new method to control flow and transport phenomena in lab-on-a-chip and a new perspective on turbulence