The purpose of this study was to study in some detail
host factors which influence the population dynamics of
bark beetle. The dissertation objectives were to ascertain
the applicability of utilizing osmotic pressure
values and relative turgidity values of phloem tissue as
indicators which reflect upon the physiological profile
of...
Foliage from Douglas-fir(var. glauca) seedlings grown under two light intensities was bioassayed to examine palatability to the
western spruce budworm (Choristoneura occidentalis Free.). Samples were collected in Fall, Winter and early Spring to
identify seasonal changes in host foliage, as evidenced by the response of spruce budworms. Fall collected foliage...
Published September 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
I developed a priori hypotheses and used logistic regression to model Greater Sandhill
Crane (Grus canadensis tabida) nest success in relation to weather, habitat and management variables for cranes breeding at Malheur National Wildlife Refuge (MNWR) in southeast Oregon. My primary interest was to investigate the effects of habitat conditions...
Published May 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
This paper is divided into two parts. The first part
traces (in details providing proofs and examples) the
history of the solutions of polynomial equations(of the
first, second, third, and fourth degree) by radicals from
Babylonian times (2000 B.C.) through 20th century. Also it
is shown that there is no...
The efficacy of a new broad-spectrum anthelmintic, Netobimin[subscript R]
(coded SCH 32481-Schering Corporation) was evaluated in two trials
conducted during either the spring or fall grazing seasons of 1984 in
Western Oregon using 20 cross-bred yearling beef heifers and 30
cross-bred spring lambs, respectively. Percent efficacies were
determined in both...
Linear programming is a recent development in the field of Mathematics having its origin in the past seventy-five years. The purpose of this study was to identify several methods for solving linear programming problems. The algorithm for each of the methods is described in detail along with an analysis of...
Ecologists have studied the responses of pelagic ecosystems
to varying levels of nutrient loading and fish predation on many
different scales ranging from small experimental enclosures to
whole lake systems. There are recurring patterns of response to
these two variables, which are generally predictable on the basis
of biogeographic, behavioral,...
In budding yeast, many of the genes that encode enzymes required for DNA precursor synthesis (MCB genes) are expressed under cell cycle control in late G1/S. The relationship between MCB gene expression, dNTP synthesis and DNA synthesis was investigated by using α factor-synchronized Saccharomyces cerevisiae. The levels of all four...
By inverting EarthScope long-period magnetotelluric (MT) data from the southeastern United States (SEUS), we obtain electrical conductivity images that provides key insights into the geodynamics of this region. Significantly, we resolve a highly electrically resistive block that extends to mantle depths beneath the modern Piedmont and Coastal Plain physiographic provinces....
Magnetotelluric (MT) data from two sites 150 and
300 km southeast of San Francisco, California (geomagnetic
dipole latitude: 43 degrees, L approximately 1.9) show that
the usual MT assumption of spatially uniform external magnetic
fields is violated to a significant degree in the period
range 10-30 s. Inter-station transfer functions...
Full Text:
functions" by Gary D. Egbert, Markus Eisel,
O. Sierra Boyd, and H. Frank Morrison
Gary D. Egbert and
Magnetotelluric (MT) data from two sites 150 and
300 km southeast of San Francisco, California (geomagnetic
dipole latitude: 43 degrees, L approximately 1.9) show that
the usual MT assumption of spatially uniform external magnetic
fields is violated to a significant degree in the period
range 10-30 s. Inter-station transfer functions...
Full Text:
DC trains and Pc3s: Source effects in mid-latitude
geomagnetic transfer functions
Gary D. Egbert
Magnetotelluric (MT) data from two sites 150 and
300 km southeast of San Francisco, California (geomagnetic
dipole latitude: 43 degrees, L approximately 1.9) show that
the usual MT assumption of spatially uniform external magnetic
fields is violated to a significant degree in the period
range 10-30 s. Inter-station transfer functions...
Managing for species using current weather patterns fails to incorporate the uncertainty associated with future climatic conditions; without incorporating potential changes in climate into conservation strategies, management and conservation efforts may fall short or waste valuable resources. Understanding the effects of climate change on species in the Great Plains of...
Full Text:
. Pitman. 2016. The relative contribution of climate to changes in lesser
prairie- chicken abundance
Invertebrates are an important food source for grouse chicks, especially within the first 2 weeks of life. Invertebrate abundance is highly patchy and dependent upon herbaceous cover and vegetation structure. We examined the relationship between invertebrate biomass (from sweepnet samples) and habitat structure at lesser prairie-chicken (Tympanuchus pallidicinctus) brood-use and...
Inclusion of substantial levels of raw-frozen Pacific hake
(Merluccius productus) in diets of ranch-raised mink (Mustela vison)
causes a large percentage of animals to develop an abnormal condition
termed "cotton fur" (CF), characterized by depressed body
weight, microcytic-hypochromic anemia and a failure of under-fur
pigmentation. Observations by several groups of...
The Purpose of the Study
The purpose of the study was to gain a better understanding of
the classroom environment by determining if student attitudes are
significantly related to the quantity and characteristics of verbal
interaction. A second concern was to determine if such verbal
interaction could be effectively examined...
Intensification of livestock operations has enhanced the problem
of animal waste disposal. Since high application rates of the
waste to soils would help elevate the problem, a study was established
to determine water quality as affected by applications of dairy
waste slurries to tiled and untiled soils.
Dairy cow waste...
The western Nearctic species of the genus Phytocoris Fallen were
taxonomically revised. Over 15,000 specimens were examined.
Information concerning host plant associations and distributions was
compiled and summarized for use by future researchers. External
morphological features and characters of the male genitalia were used
to distinguish species. The genital tubercles...
An optimal interpolation (OI) sequential algorithm is implemented for a three-dimensional primitive equation model to assimilate current measurements from acoustic Doppler profilers moored on the Oregon shelf as a part of the Coastal Ocean Advances in Shelf Transport (COAST) upwelling experiment (May–August 2001). A stationary estimate of the forecast error...
This report documents oceanographic and meteorological measurements made from instruments deployed on four moorings over the continental shelf west of Oregon, from spring through
summer, 1999. These moorings were a component of an observational and numerical modeling program to study the response of the coastal ocean to wind forcing.
The...
Published July 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The interaction of the dominant semidiurnal M₂ internal tide with the large-scale subtidal flow is examined
in an ocean model by propagating the tide through an ensemble of background fields in a domain centered on
the Hawaiian Ridge. The background fields are taken from the Simple Ocean Data Assimilation (SODA)...
Many records provide the bases for a clearer understanding of the roles of climate regime shifts and short-term perturbations in ecosystem dynamics, hence fisheries responses. Too few have taken the long view of the role of humans in this "Grand Fugue". As one of many predators, it is imperative that...
Live western larch, Larix occidentalis Nutt., a tree species resistant to the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, produces the monoterpene 3-carene in higher concentrations compared to Douglas-fir, the preferred host of D. pseudotsugae (Reed et al. 1986). The inhibitory effects on attraction to aggregation pheromones and toxicity of 3-carene to...
Conservation of wildlife depends on an understanding of the interactions between animal movements and key landscape factors. Habitat requirements of wide-ranging species often vary spatially, but quantitative assessment of variation among replicated studies at multiple sites is rare. We investigated patterns of space use for 10 populations of two closely...
This thesis is an investigation of the natural products deriving from marine algae and cyanobacteria and has resulted in the discovery of eleven new secondary metabolites. The structure elucidations of these new molecules were performed using a variety of spectroscopic techniques. Four new macrolides were isolated and characterized from the...
This thesis describes the chemical investigation of marine cyanobacteria collected in Madagascar and Panama with an emphasis on the isolation and structure elucidation of medicinally relevant secondary metabolites.
A collection of the marine cyanobacterium Lyngbya majuscula from the Radames Islands, Madagascar yielded two new cyclic depsipeptides, radamamides A and B,...
This thesis is an account of investigation on the natural products deriving from various marine algae and has resulted in the discovery of eleven novel bioactive metabolites. Isolation and characterization of these new molecules were carried out using different chromatographic techniques and by analyses of different spectroscopic data, respectively. Using...
The purpose of the study was to investigate the effect of trials-to-criterion on the retention of a discrete motor skill (overhand beanbag throw) by moderately mentally retarded and severely mentally retarded individuals. Nonmentally retarded individuals were involved as a control group. The subjects were grouped by degree of retardation and...
Recent geophysical and geological investigations of the Tibetan plateau have given rise to conflicting models of plateau growth and deformation, where the presence and extent of partial melt in the crust could be a determining factor. Here we investigate the attenuation structure of the crust and upper mantle, as attenuation...
Gall-associated phytopathogens have unique evolutionary histories that haveshaped both their modes of infection and genomic structures. Pathogenicity of the gall-associated plant pathogens of the Rhodococcus, Agrobacterium, and Rathayibactergenera is mediated by horizontally acquired virulence loci. The relative ease of gainand loss of the virulence loci has confounded accurate characterization of...
Indole-3-carbinol (I3C) and 3,3'-diindolylmethane (DIM), a primary I3C
derivative in vivo, are known chemopreventive agents available as dietary supplements.
I3C was found to suppress or enhance tumors in several animal models.
Chemoprotection is attributed to the ability of indoles to alter carcinogen metabolism
effectively blocking initiation. However, mechanisms for enhancement...
The sperm whale (Physeter macrocephalus) shows some of the most derived characteristics of any mammal: a large body size, large brain, complex social organization and a capacity for deep foraging dives that few other marine mammals can match. Despite a history of exploitation that removed hundreds of thousands of individuals,...
Magnetotelluric exploration has been used to image along strike variations in the electrical resistivity structure of the San Andreas Fault at Parkfield, California. A low resistivity wedge extending to a depth of several kilometers is continuous over a horizontal distance of 8 km. The base of the wedge is coincident...
Operations management researchers have frequently suggested that autonomy can motivate teams to actively and flexibly adapt to fast-changing environments, fostering innovation and creative problem solving. However, empirical studies have not consistently supported the benefits of team autonomy. We articulate the behavioral and mechanistic effects of team autonomy by integrating operations...
Areas with high species richness have become focal points in the establishment of
marine protected areas, but an understanding of the factors that support this diversity is still
incomplete. In coastal areas, tidal currents—modulated by bathymetry and manifested in variable
speeds—are a dominant physical feature of the environment. However, difficulties...
We conducted a comparative hazard assessment for 325,000 ha in a fire-prone area of southwest Oregon, USA. The landscape contains a variety of land ownerships, fire regimes, and management strategies. Our comparative hazard assessment evaluated the effects of two management strategies on crown fire potential and northern spotted owl (Strix...
Measurements of tidal currents on the central Oregon shelf are available from several sources, including recent high frequency (HF) coastal radar and Acoustic Doppler Profiler (ADP) deployments, and historical current moorings. In this paper we use a generalized inverse (GI) approach to compare these data to, and then assimilate them...