Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 181-205).

Thesis (Ph. D.)--University of California, Los Angeles, 2003. / Vita. Includes bibliographical references.

Thesis (MS) University of Montana, 2008. / Title from author supplied metadata. Contents viewed on May 19, 2010. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2002. / Heading on electronic reproduction: Anderson, Nancy Lee. Vita. Includes bibliographical references (leaves 168-176).

We have completed a search for low luminosity companions, including high mass brown dwarfs, to all M dwarfs known within eight parsecs of the sun, and north of -25°. We found six new companions orbiting the survey stars. The masses of the six new secondaries fall between 0.39 and 0.05 M(⊙). Three of the new companions, G208-44B, GL 623B and LHS 1047B, and one previously known secondary in the survey, Ross 614B, are brown dwarf candidates with masses ∼80 Jupiters (0.08 M(⊙)), the dividing line between stars and brown dwarfs. In addition, we provide infrared photometry at J, H and K for all 99 survey members, and spectral types on standard system for half. Analysis of the entire sample indicates that 50% of the stars in the more distant half of the survey volume remain undetected, as is supported by the steadily growing M dwarf census over the last 45 years. The binary fraction of M dwarfs, 30-40%, is lower than that of earlier type main sequence stars, and there are more companions to M dwarfs found between 1 and 10 AU than in any other decade interval. We find that the luminosity function of the lowest mass stars is flat or rising to the end of the main sequence, and that the mass function undoubtedly rises to the stellar/substellar break. We illustrate that the resolution of close binaries is crucial if accurate luminosity and mass functions are to be determined. Finally, we estimate 0.02 M(⊙)/pc³ to be the amount of mass contributed by M dwarfs to the galactic mass. Based upon new mass-luminosity relations developed at infrared wavelengths using a sample of stars with well-determined masses between 1.2 and 0.08 M(⊙), we are able to define empirically the end of the main sequence. We present absolute magnitudes, colors and spectral types for objects at the theoretical lowest stellar mass. Using these relations, we conclude that a few brown dwarfs may have already been discovered. (Abstract shortened with permission of author.)

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This thesis has explored the historiography on John Brown from 1859 to 1970. Over 200 sources have been examined and analyzed to determine their pro or anti John Brown bias. General trends in opinion were noted as the study progressed chronologically. Specific representative works by various authors, especially those which influence ensuing Brown historiography, were dealt with in detail, particularly in the areas of Brown's sanity, his Kansas activities, and the Harper's Ferry foray. From early eulogies, Brown historiography moved to predominantly critical expressions and then seemed to attain a balance between the two extremes. Charts preceding each chronological section of the paper demonstrate the attitudes held by authors writing during that period.

Investigations into perispawning mortalities in the brown trout (Salmo trutta L) population of Loch Leven, Kinross, revealed that death occurred as a result of infection with a particular species of Saprolegnia diclina Humphrey type 1. Increased surface area of infection was correlated with a decrease in ion and protein content of the blood and was further reflected by changes in the electrocardiogram pattern. These changes were essentially a widening of the QRS complex with inflection of the RS component, changes consistent with a decrease in certain ions in mammals. Histological changes associated with sexual maturity and fungal infection are described and compared with changes resulting from the administration of androgens to brown trout.

A study of clouds and variability in brown dwarf atmospheres is presented, with a focus on understanding the mechanism by which condensate clouds are dissipated at the transition between L and T spectral types. The results of a large J-band variability survey of over 60 mid-L to T dwarfs, and related observations are presented. We find statistically significant evidence (at the 95% confidence level) for an increase in large amplitude variability (peak to peak variations larger than 2%) within the L/T transition (L9-T3.5 spectral types), suggesting that the disruption of dust clouds by weather phenomena may contribute to the rapid decline in condensate opacity and J-band brightening observed to occur in this regime. Alternatively, the large amplitude variability observed could be the result of increasing contrast between discrete cloud features and the underlying atmosphere, rather than the development of cloud holes. We highlight the discovery of a T dwarf with 26% variability, and provide a detailed comparison with atmosphere models in order to infer the nature of cloud features responsible. Results are consistent with both the presence of thick storm features or cloud holes in our target's atmosphere, but are inconsistent with the presence of magnetic spots. Supporting work related to clouds in L dwarf atmospheres, and the L/T transition binary fraction is presented. From studying an unusually blue L-dwarf companion to a nearby M-dwarf star we infer that thin or patchy condensate clouds, rather than low metallicity and/or high surface gravity, are most likely responsible for its peculiar colors. The discovery of significant variability for a different blue L dwarf in our large variability survey provides further evidence for this hypothesis. Finally, combining our own high contrast imaging observations for 8 L/T transition targets with previous results we infer a resolved L/T transition binary fraction of 14(+7-6)%, consistent with that inferred for the general brown dwarf population. This latter result suggests that the L/T transition sample is not highly contaminated by unresolved multiples.