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Energies of Rare-Earth Ion States Relative to Host Bands in Optical Materials from Electron Photoemission Spectroscopy: Author: Thiel, Charles Warren; Date: 2003-12-15; Program: Physics; Abstract: There are a vast number of applications for rare-earth-activated materials and much of today's cutting-edge optical technology and emerging innovations are enabled by their unique properties. In many of these applications, interactions between the rare-earth ion and the host material's electronic states can enhance or inhibit performance and provide mechanisms for manipulating the optical properties. Continued advances in these technologies require knowledge of the relative energies of rare-earth and crystal band states so that properties of available materials may be fully understood and new ...; Download File | View full details

The Influence of Landscape Characteristics on Duck Nesting Success in the Missouri Coteau Region of North Dakota: Author: Stephens, Scott Eugene; Date: 2003-12-15; Program: Fish and Wildlife Biology; Abstract: Because of the importance of nesting success to avian population dynamics, and the extensive and ubiquitous nature of habitat fragmentation, many studies have attempted to address the relationship between fragmentation and nesting success. However, an overall theory of fragmentation effects on nesting success has remained elusive. First, we reviewed published literature to examine fragmentation effects on nesting success at three spatial scales (i.e., edge, patch, and landscape scales). We identified 86 relevant manuscripts that provided 117 individual tests of hypotheses regarding the effects...; Download File | View full details

Restoration of Spotted Knapweed Infested Grasslands in Glacier National Park: Author: Stringer, Lewis Tipton; Date: 2003-12-15; Program: Land Rehabilitation; Abstract: There is an immediate and on-going need in Glacier National Park (GNP), and other public and private lands, to determine effective methods to re-establish and sustain native plant populations following control treatments of Centaurea maculosa. My research was developed in response to GNP concerns regarding annual herbicide treatment of C. maculosa invaded sites. The aim of this study was to determine if herbicide applications, site preparation and revegetation methods would increase the density and percent cover of native species, while reducing spotted knapweed at two sites in and near Glacie...; Download File | View full details

Simultaneous Two-Photon Absorption of Tetrapyrrolic Molecules: From Femtosecond Coherence Experiments to Photodynamic Therapy: Author: Karotki, Aliaksandr; Date: 2003-12-15; Program: Physics; Abstract: Simultaneous two-photon absorption (TPA) in tetrapyrrolic molecules is studied and its applications to two-photon coherence gratings and singlet oxygen generation for photodynamic therapy are demonstrated in this thesis. First ever comprehensive study of TPA properties of tetrapyrrolic molecules is conducted in this work. Two-photon transitions in two key spectral regions, red to green and blue to near-UV (transition wavelengths) are investigated. Physical mechanisms leading to enhancement of TPA cross section in tetrapyrroles are elucidated. Porphyrin molecules with greatly enhanced two-photo...; Download File | View full details

The Sinc-Galerkin Method for Problems in Oceanography: Author: Koonprasert, Sanoe; Date: 2003-12-15; Program: Mathematics; Abstract: The model for a wind-driven current with depth-dependent eddy viscosity is developed as a complex velocity formulation and a coupled system formulation. The numerical solutions, calculated by a Sinc-Galerkin method, are compared. A fully Sinc-Galerkin method in both space and time for a partial differential equation with time-dependent boundary conditions is developed. This entirely new technique is applied to the model for a wind-driven current with time-dependent viscosity. Several numerical examples are used to test the performance of the method. This fully Sinc-Galerkin method is then appl...; Download File | View full details