Doctor of Philosophy

dissertationRecent racially charged events have brought renewed focus on racial tensions in the United States, effectively ending the myth of a postracial society. Moreover, the recalcitrance of race-relevant social problems suggests that current methods of addressing those problems are inadequate, or at least incomplete. Such is the case with the received view, social constructivism, according to which race results from historically and culturally specific practices and decision. New psychological research challenges the received view, suggesting that racial cognition results in part from psychological mechanisms that operate outside of the conscious awareness of human agents. This body of research has led to interactionist, complementarian constructivist models of race. Ron Mallon and Dan Kelly's position, "hybrid constructionism," advances the claim that "racial social roles are psychologically constrained." My position, the psychological construction of race, is committed to something more specific-that opaque psychological mechanisms are foundational to social construction, that is, that the individual psychology constructs the subsequent social constructions. In short, if hybrid constructionism is "constraint-ist," psychologically constructed race is purely constructivist

Correspondence between sound propagation in discrete and continuous random media with application to forest acoustics

Although sound propagation in a forest is important in several applications, there are currently no rigorous yet computationally tractable prediction methods. Due to the complexity of sound scattering in a forest, it is natural to formulate the problem stochastically. In this paper, it is demonstrated that the equations for the statistical moments of the sound field propagating in a forest have the same form as those for sound propagation in a turbulent atmosphere if the scattering properties of the two media are expressed in terms of the differential scattering and total cross sections. Using the existing theories for sound propagation in a turbulent atmosphere, this analogy enables the derivation of several results for predicting forest acoustics. In particular, the second-moment parabolic equation is formulated for the spatial correlation function of the sound field propagating above an impedance ground in a forest with micrometeorology. Effective numerical techniques for solving this equation have been developed in atmospheric acoustics. In another example, formulas are obtained that describe the effect of a forest on the interference between the direct and ground-reflected waves. The formulated correspondence between wave propagation in discrete and continuous random media can also be used in other fields of physics

Analysis of The Fluidized Bed Drying of Wood Particles

Engineering parameters necessary to design an industrial, continuous fluidized-bed dryer for wood particles were examined using a 0.21-m square batch fluidized-bed dryer. Parameters of main interest were gas velocity and drying curves, but bed voidage, particle elutriation, and distributor plate design also were considered. For unscreened (mixed sizes) hammermilled wood and sawdust, the minimum gas velocities for fluidization were 1.03 and 0.55 m/s, respectively. These values increased with increasing moisture content, decreasing sphericity, and increasing particle diameter. Current methods of adjusting batch drying curves so that they can be applied to a commercial continuous dryer were shown to be inadequate for some wood particle sizes. To predict drying curves for all particle sizes, a new method was developed that accounts for both internal and external resistances to drying. The new method was confirmed experimentally

Breeding Bird Communities in Pine Plantations On the Coastal Plain of North Carolina

Prior to European settlement of North America, the landscape of the Southeastern United States was dominated by an estimate 55 million hectares of old growth forests (Ware et al. 1993). Since that time, three centuries of land clearing for agriculture and other uses has reduced the extent of forest cover to 60% of its former range..

Transcriptional repression by ApiAP2 factors is central to chronic toxoplasmosis

Tachyzoite to bradyzoite development in Toxoplasma is marked by major changes in gene expression resulting in a parasite that expresses a new repertoire of surface antigens hidden inside a modified parasitophorous vacuole called the tissue cyst. The factors that control this important life cycle transition are not well understood. Here we describe an important transcriptional repressor mechanism controlling bradyzoite differentiation that operates in the tachyzoite stage. The ApiAP2 factor, AP2IV-4, is a nuclear factor dynamically expressed in late S phase through mitosis/cytokinesis of the tachyzoite cell cycle. Remarkably, deletion of the AP2IV-4 locus resulted in the expression of a subset of bradyzoite-specific proteins in replicating tachyzoites that included tissue cyst wall components BPK1, MCP4, CST1 and the surface antigen SRS9. In the murine animal model, the mis-timing of bradyzoite antigens in tachyzoites lacking AP2IV-4 caused a potent inflammatory monocyte immune response that effectively eliminated this parasite and prevented tissue cyst formation in mouse brain tissue. Altogether, these results indicate that suppression of bradyzoite antigens by AP2IV-4 during acute infection is required for Toxoplasma to successfully establish a chronic infection in the immune-competent host

Quenching Effects in the Hadron Spectrum

Lattice QCD has generated a wealth of data in hadronic physics over the last two decades. Until relatively recently, most of this information has been within the "quenched approximation" where virtual quark--anti-quark pairs are neglected. This review presents a descriptive discussion of the effects of removing this approximation in the calculation of hadronic masses.Comment: To appear in "Lattice Hadron Physics", ed. A.C. Kalloniatis, D.B. Leinweber and A.G. William

Observations of Unsteady Airfoil Flows

http://deepblue.lib.umich.edu/bitstream/2027.42/96610/1/39015087358597.pd

Proximal Sciatic Nerve Intraneural Ganglion Cyst

Intraneural ganglion cysts are nonneoplastic, mucinous cysts within the epineurium of peripheral nerves which usually involve the peroneal nerve at the knee. A 37-year-old female presented with progressive left buttock and posterior thigh pain. Magnetic resonance imaging revealed a sciatic nerve mass at the sacral notch which was subsequently revealed to be an intraneural ganglion cyst. An intraneural ganglion cyst confined to the proximal sciatic nerve has only been reported once prior to 2009