Zugl.: Karlsruhe, Universiẗat, Diss., 2007.

Thesis (MS )--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Mark L. Taper. Includes bibliographical references (leaves 60-68).

Thesis (Ph. D.)--University of Oregon, 2000. / Title from title screen. Extent of document: xiv, 152 p. : ill. Includes vita and abstract. Includes bibliographical references (p. 146-152).

Stuttgart, Univ., Diplomarb., 2004.

Thesis (MS )--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Mark L. Taper. Includes bibliographical references (leaves 60-68).

Zugl.: Bamberg, Universiẗat, Diss., 2008.

Crystalline minerals such as fluorite have been recovered from numerous prehistoric sites in the Midcontinent yet little research had previously been conducted concerning who used it and what they used it for. Ethnohistorical accounts inform us that crystalline minerals were of importance to American Indians during the Historic Period. These accounts are used to provide a basis for exploring the possible significance of fluorite to prehistoric peoples living near outcrops located along the lower Ohio River valley. In this thesis I analyze mainly prehistoric fluorite personal adornment items as well as similar items made from other locally available raw materials such as cannel coal and clay to gain an understanding of the importance of this colorful crystalline mineral to prehistoric inhabitants of the midcontinent.

[pt] Um esquema conceitual de banco de dados, ou simplesmente um esquema, é a descrição em alto nível de como os conceitos de um banco de dados estão organizados. O alinhamento de um esquema origem S em um esquema destino T define conceitos em T nos termos dos conceitos de S. Esse trabalho descreve uma ferramenta de software que auxilia a implementação de técnicas de alinhamento de esquemas OWL baseadas em instâncias, que dependem da definição de funções de similaridade para avaliar a proximidade semântica dos elementos de dois esquemas diferentes. A ferramenta foi projetada para permitir a utilização de diferentes funções de similaridade e a troca dos algoritmos de alinhamento, facilitando assim a experimentação com diferentes configurações de alinhamento. / [en] A database conceptual schema, or simply a schema, is a high level description of how database concepts are organized. The schema matching from a source schema S into a target schema T defines concepts in T on terms of the concepts in S. This work describes a software tool that helps implement instancebased schema matching techniques for OWL dialects that depend on the definition of similarity functions to evaluate the semantic proximity of elements from two different schemas. The tool is designed to accommodate different similarity functions and distinct matching algorithms, thereby facilitating experimenting with alternative matching configurations.

Advisers: Terry Takahashi and Richard Marrocco. xiv, 152 p. / Neurons in the barn owl's inferior colliculus (IC) derive their spatial receptive fields (RF) from two auditory cues: interaural time difference (ITD) and interaural level difference (ILD). ITD serves to restrict a RF in azimuth but the precise role of ILD was, up to this point, unclear. Filtering by the ears and head insures that each spatial location is associated with a unique combination of frequency-specific ILD values (i.e., an ILD spectrum). We isolated the effect of ILD spectra using virtual sound sources in which ITD was held fixed for all spatial locations while ILD spectra were allowed to vary normally. A cell's response to these stimuli reflects the contribution of ILD to spatial tuning, referred to as an “ILD-alone RF”. In a sample of 34 cells, individual ILD-alone RFs were distributed and amorphous, but consistently showed that the ILD spectrum is facilatory at the cell's best location and inhibitory above and/or below. Prior results have suggested that an IC cell's spatial specificity is generated by summing inputs which are narrowly tuned to frequency and selective for both ILD and ITD. Based on this premise, we present a developmental model which, when trained solely on a cell's true spatial RF, reproduces both the cell's true RF and its ILD-alone RF. According to the model, the connectivity between a space-tuned IC cell and its frequency-specific inputs develops subject to two constraints: the cell must be excited by ILD spectra from the cell's best location and inhibited by spectra from locations above and below but along the vertical strip defined by the best ITD. To assess how frequency-specific inputs are integrated to form restricted spatial RFs, we measured the responses of 47 space-tuned IC cells to pure tones at varying ILDs and frequencies. ILD tuning varied with frequency. Further, pure-tone responses, summed according to the head-related filters, accounted for 56 percent of the variance in broadband ILD-alone RFs. Modelling suggests that, with broadband sounds, cells behave as though they are linearly summing their inputs, but when testing with pure tones, non-linearities arise. This dissertation includes unpublished co-authored materials.

xiv, 152 p. Adviser: Terry Takahashi (Biology Dept.). Chapter 2 of this dissertation has been previously published in the Journal of Neurophysiology. Citation: Whitchurch EA and Takahashi TT. Combined auditory and visual stimuli facilitate head saccades in the barn owl (Tyto alba). J Neurophysiol 96: 730-745, 2006. / A print copy of this title is available through the UO Libraries under the call number: SCIENCE QL696.S85 W54 2006 / Survival depends on our ability to detect and integrate sensory information from multiple modalities, allowing for the most efficient behavioral response. For example, barn owls must combine sights and sounds from the environment to localize potential prey. A vole scurrying through a drift of dried leaves is more likely to meet its doom if a nearby owl can both faintly see and hear it. How does the brain take two physically discreet inputs and combine them into a unified representation of the surrounding multisensory world? Moreover, how is this internal representation transformed into the most efficient behavioral response? This dissertation comprises original research addressing these questions in the barn owl with two distinct approaches: First, Chapters II and III describe orientation behavior in response to auditory, visual, and audiovisual stimuli. Chapter II probes the effect of stimulus strength on saccadic behavior and the nature of audiovisual integration, and was taken from a co-authored publication. Chapter III explores the behavioral consequence of an induced stimulus asynchrony in audiovisual integration and was taken from a co-authored manuscript being prepared for publication. The second experimental approach is described in Chapters IV and V. These chapters probe the physiological basis of saccadic behavior by measuring single-neuron responses to auditory, visual, and audiovisual stimuli. Chapter IV describes how auditory responses of neurons from the external nucleus of the inferior colliculus depend on sound pressure level. Chapter V describes activity of optic tectum neurons in response to auditory, visual, and audiovisual stimuli. The behavioral findings described herein suggest that barn owls often incorporate both the speed of the auditory system and the accuracy of the visual system when localizing a multisensory stimulus, even when the two modalities are presented asynchronously. The physiological studies outlined in this dissertation show that sensory representations in the midbrain can be used to predict general trends in saccadic behavior: Neuronal thresholds were within the range of observed behavioral thresholds. Responses to multisensory stimuli were enhanced relative to unisensory stimuli, possibly corresponding to enhanced multisensory behavior. These data support fundamental rules in multisensory integration that may apply across species.