Mississippi State University

About: Mississippi State University is a education organization based out in Starkville, Mississippi, United States. It is known for research contribution in the topics: Population & Catfish. The organization has 14115 authors who have published 28594 publications receiving 700030 citations. The organization is also known as: The Mississippi State University of Agriculture and Applied Science & Mississippi State University of Agriculture and Applied Science.

Reassessing the Racial Divide in Support for Capital Punishment The Continuing Significance of Race

Abstract: This project investigates the racial divide in support for capital punishment. The authors examine whether race has a direct effect on support for capital punishment and test whether the influence of race varies across class, being a native southerner, confidence in government officials, political orientation, and religious affiliation. Using data drawn from the General Social Survey, they find a substantial racial divide, with African Americans much less likely to support the death penalty. Furthermore, the analysis revealed little support for the “spurious/social convergence” hypothesis; shared factors that might be expected to bring African Americans and Whites together—class, confidence in government, conservative politics, regional location, and religious fundamentalism—either did not narrow African American-White punishment attitudes or, at best, had only modest effects. The Results suggest that the racial divide in support for capital punishment is likely to remain a point of symbolic contention in...

The bursa of Fabricius and immunoglobulin synthesis.

Abstract: Publisher Summary This chapter discusses the Bursa of Fabricius and immunoglobulin synthesis. It emphasizes on bursa morphology, bursa kinetics, and bursa regulation of immunoglobulin production synthesis. Scanning electron microscope and transmission electron microscopy have revealed two distinct types of epithelial cells covering the plicae of the bursa. The chapter explains how epithelial cells involved in bursa ontogeny, specifically the development of bursal lymphocytes. Information from experiments concerning lymphocyte turnover within the bursal compartment would allow one to measure the subtle influences of the environment and exogenous chemicals on the production of B cells. It is suggested that the bursa of the chick embryo or neonate be utilized as the effector tissue in a biological assay for potential factors influencing B-cell maturation. The partial reconstitution of antibody production of BSX birds by injection of bursal extracts, or the implantation of Millipore filters containing bursal segments has suggested the existence of a soluble bursal factor (SBF) capable of effecting cell transformation or amplification of a small population of preexisting immunocompetent cells.

Instability in Half-Bridge Circuits Switched With Wide Band-Gap Transistors

Abstract: Wide band-gap (WBG) field-effect devices are known to provide a system-level performance benefit compared to silicon devices when integrated into power electronics applications. However, the near-ideal features of these switching devices can also introduce unexpected behavior in practical systems due to the presence of parasitic elements. The occurrence of self-sustained oscillation is one such behavior that has not received adequate study in the literature. This paper provides an analytical treatment of this phenomenon by casting the switching circuit as an unintentional negative resistance oscillator. This treatment utilizes an established procedure from the oscillator design literature and applies it to the problem of power circuit oscillation. A simulation study is provided to identify the sensitivity of the model to various parameters, and the predictive value of the model is confirmed by experiment involving two exemplary WBG devices: a SiC vertical-channel JFET and a SiC lateral-channel MOSFET. The results of this study suggest that susceptibility to self-sustained oscillation is correlated to the available power density of the device relative to the parasitic elements in the circuit, for which wide band-gap devices, to include SiC and GaN transistors, are in a class approaching that of the radio frequency domain.

Optimization of the LENS® process for steady molten pool size

Abstract: A three-dimensional finite element model was developed and applied to analyze the temperature and phase evolution in deposited stainless steel 410 (SS410) during the Laser Engineered Net Shaping (LENS ®,1 ) rapid fabrication process. The effect of solid phase transformations is taken into account by using temperature and phase dependent material properties and the continuous cooling transformation (CCT) diagram. The laser beam is modeled as a Gaussian distribution of heat flux from a moving heat source with conical shape. The laser power and translational speed during deposition of a single-wall plate are optimized in order to maintain a steady molten pool size. It is found that, after an initial transient due to the cold substrate, the dependency of laser power with layer number is approximately linear for all travel speeds analyzed. The temperature distribution and cooling rate surrounding the molten pool are predicted and compared with experiments. Based upon the predicted thermal cycles and cooling rate, the phase transformations and their effects on the hardness of the part are discussed. © 2007 Elsevier B.V. All rights reserved.