In this thesis I studied several THz components that can be used for potential THz
technology. THz waves were generated in nonlinear medium via optical rectification
of femtosecond optical pulses. Utilizing the phase matching condition between the
optical and THz waves in a ZnTe crystal, single-cycle broad-band THz pulses were...
A study was made to determine the distribution of parasites of the larch casebearer, Coleophora laricelia, within crowns of western larch, Larix occidentalis. The most common parasites recovered in order of their abundance, were: Agathis pumila (Ratz.), Diciadocerus sp. near westwoodii, Spilochalcis albifrons (Walsh), and MesopoZobus sp. Parasitism by A....
Mountain pine beetle, Dendroctonus ponderosas Hopk., reached near epidemic levels in lodgepole pine stands in the Sulphur Creek-Black Butte area. Lodgepole pine are probably more susceptible due to the overstocked conditions of stands, and high incidence of girdling of the base of trees by porcupines. The infestation in this area...
Wright's Point, a 250-foot-high, sinuous, flat-topped ridge, projects eastward into Harney Basin, Harney County, Oregon. This 6-mile-long feature ranges from 200 to 600 yards wide and merges with a broad mesa at its western end. The nearest topographic highs are Dog Mountain, 2 miles southwest, and foothills of the Blue...
(1) Field mapping and biostratigraphic data indicate that the Yamhill Formation overlies and is younger than the Tyee Formation; interfingering of the two formations is not indicated. (2) Stewart's correlation of the Yamhill Formation with the Sacchi Beach member of the Tyee was based on incomplete knowledge of the range...
The platinum-group metals have been the subject of considerable discussion in the news media over the past few months, particularly because of their projected use as catalysts in automobile engines. Metals Week of August 27 shows that platinum commands a price of $176.00 per ounce, as compared to $150.00 per...
The Mixteco primarily reside in the Mexican State of Oaxaca in Southwestern Mexico. They have been arriving in larger numbers then ever before to this part of the North American continent in the last twenty years.Their experience is composed of different dynamics compared to those of their mainstream Mexican counterpart....
Dwarf mistletoe is known to reduce both height and diameter growth and thus reduce the yield of an infested stand. This comparison of two similar stands--one healthy and the other infested--gives an indication of the impact of this parasite. The healthy stand has produced 1.5 times the board foot volume...
This report documents the establishment of a study to determine the effect of thinning on incidence of mountain pine beetle, Dendroctonus ponderosae Hopk., infestation in second-growth ponderosa pine stands in western Montana.
Although insufficient time has passed for a similar study in Oregon to yield a solid base for a...
An evaluation of the status of bark beetle infestations in ponderosa pine stands on Blue Mountain, Missoula District, Lolo National Forest, was made March 30 and April 4, 1972, at the request of personnel of the Missoula District.
Extensive group killing of ponderosa pine in the vicinity of Blue Mountain...
The mountain pine beetle, Dendroctonus ponderosas Hopk., showed a significant advance northward from the 1970 infestation boundary, encompassing almost one-third of the total Park acreage. A fall survey conducted in the Park showed an average of 71.1 trees per acre with red or fading foliage from previous year's attacks and...
The price of gold has risen from $60.35 per ounce in mid-November, 1972, to $91.25 per ounce in mid-April, 1973. The present high price has caused considerable speculation as to the underlying reasons for the sudden increase and what effect it may have on the international monetary situation. This precious...
The plate tectonic history of Oregon is but one piece of a worldwide jigsaw puzzle encompassing much of geologic time. With the splitting of Pangaea in Mesozoic times, Oregon has occupied the leading edge of the North American Plate as it has impinged upon the ancestral oceanic East Pacific Plate....
Quantitative resistance (QR) to disease is usually more durable than qualitative resistance, but its genetic basis is not well understood. We used the barley/barley stripe rust pathosystem as a model for the characterization of the QR phenotype and associated genomic regions. As an intermediate step in the preparation of near-isogenic...
Larval transport and retention of two endangered suckers were studied in a highly
altered lacustrine/riverine complex. The endangered populations of Lost River sucker,
Deltistes luxatus, and shortnose sucker, Chasmistes brevirostris, in Upper Klamath Lake
(UKL), Oregon are the largest remnant populations of these suckers. Downstream of
UKL, the Keno Impoundment...
The biological transformation of dinitrogen gas (N2) into combined forms(termed N2 fixation) by certain genera of oceanic cyanobacteria represents the largest incoming flux of nitrogen to the global ocean. As such, biological nitrogen fixation
plays a significant role in the regulation of oceanic productivity and the export of
carbon and...
Recent science education reforms have placed a large emphasis on inquiry-based teaching strategies as an effective way of improving conceptual understanding of science principles, comprehension of the nature of scientific inquiry, and development of the abilities for inquiry (NRC, 1996). To better understand the relationship between inquiry-based instruction and student...
Bold, rocky headlands alternating with long curved beaches, sand spits, and bays -- these are the dominant landforms that make up the more than 40 miles of scenic coastline between Roads End and Tillamook Bay. With the exception of Cape Kiwanda, which is composed of sandstone, the headlands are made...
Resource managers of Oregon’s tidal wetlands require an improved GIS layer for management of existing tidal wetland habitat and areas considered for tidal wetland restoration. A reconnaissance project was initiated, such that interpretations of remote sensing data, the National Wetland Inventory, Oregon Estuary Plan Book and additional management tools were...
A 3-year evaluation of Douglas-fir cones in Montana and Yellowstone National Park, Wyoming, showed the western spruce budworm, Choristoneura occidentalis Freeman, and midges were the most common and injurious insects found each year. Injury was so severe at some plots that no sound seeds could be found.
Low reproductive success has been typical of high elevation populations of the Hawaiian goose (Branta sandvicensis) or nēnē. Researchers identified predation and inadequate nutrition as limiting factors. Reproductive success remained low in most years despite on-going predator control programs. I used a supplemental feeding program over two breeding seasons in...
A Z-parameter based macromodel for characterizing the substrate noise coupling in a lightly doped substrate at low frequencies has been developed. The model is scalable with contact geometries and separation. The cross-coupling impedance between two contacts is modeled using an improved geometric mean distance formulation. This approach obviates the need...
A distinct characteristic of legged locomotion is its periodic nature. This periodic motion, in the form of a periodic orbit, has been the target of many walking and running control strategies. The spring loaded inverted pendulum (SLIP) has become a popular model of sagittal plane locomotion, exhibiting behavior characteristic of...
One of the most beautiful and geologically interesting parts of the Oregon coast is in the vicinity of Cape Arago near Charleston, 10 miles west of Coos Bay. Three very fine state parks have been developed here. They are (from north to south): Sunset Bay, Shore Acres, and Cape Arago...
Our studies and those of our colleagues in Idaho indicate that the western Snake River Basin is a major geothermal province, similar in some ways to the Imperial Valley Geothermal Province. Deep drilling should encounter high temperature fluids in permeable rocks below 2 km and at shallower depths where permeability...