Spotted knapweed, Centaurea maculosa Lam. (Compositae) is an extremely
successful introduced weed species in the northwestern United States. Multiple factors
may be responsible for its success, including chemical defense. Two different types of
putative chemical defense agents are the focus of this thesis. The first is a bitter-tasting
sesquiterpene lactone,...
The purpose of this dissertation is to investigate Oregon public high school history teacher perspectives concerning standards-based reform initiatives springing from the No Child Left Behind legislation. The central question addressed in this study is: At what level has Standards-Based Education reform initiatives impacted Oregon high school history instruction and...
Diseased and healthy Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were identified at two black-stain root disease centers, caused by Leptographium wageneri var. pseudotsugae Harrington & Cobb, in the Oregon Coast Range near Coos Bay. Phloem and sapwood near the root collar were sampled monthly for 1 year, whereas roots were sampled...
Polynuclear aromatic hydrocarbons (PNAH) classified as noncarcinogens
may be photooxidized to mutagenic or toxic products by
near-ultraviolet (NUV) wavelengths of sunlight (290-320 nm). The
possibility that this represents a major degredation pathway in the
aquatic environment is of increasing concern. Large quantities of
PNAH from accidental oil spills, anthropogenic and...
Since the early 1950's, the distribution of sediment at the
mouth of Redwood Creek has been altered by the effects of channel
aggradation and channelization along the lower reach. Severe flooding
in 1953, 1955, and 1964 caused bank erosion, landsliding, and
channel geometry changes along Redwood Creek. The increased sediment...
Phellinus sulphurascens (previously the Douglas-fir form of Phellinus weirii) is an important native pathogen causing laminated root rot in forests of western North America. Visual crown symptoms, or attacks by bark or ambrosia beetles appear only during advanced stages of the disease with extensive infection in the lower bole. Ethanol...
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trees and for beetle host selection
RickG. Kelsey*, Gladwin Joseph, Doug Westlind, and Walter
Phellinus sulphurascens (previously the Douglas-fir form of Phellinus weirii) is an important native pathogen causing laminated root rot in forests of western North America. Visual crown symptoms, or attacks by bark or ambrosia beetles appear only during advanced stages of the disease with extensive infection in the lower bole. Ethanol...
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, Bangalore, India.
RickG. Kelsey a,⇑, Gladwin Joseph b,1, Doug Westlind a, Walter G. Thies a
aUSDA Forest
Phellinus sulphurascens (previously the Douglas-fir form of Phellinus weirii) is an important native pathogen causing laminated root rot in forests of western North America. Visual crown symptoms, or attacks by bark or ambrosia beetles appear only during advanced stages of the disease with extensive infection in the lower bole. Ethanol...
Key message Leyland cypress, an intergeneric hybrid, produces the same volatile heartwood compounds as its parental taxa, yellow-cedar and Monterrey cypress. However, the proportion of total sesquiterpenes and some of the individual components appear unique to their respective heartwoods.
Context Leyland cypress, xHesperotropsis leylandii is an intergeneric hybrid between yellow-cedar,...
Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 times higher ethanol level than trees with spot cankers...
The brine shrimp (Artemia salina) bioassay was used to screen 211 methanol extracts from 128 species of Pacific Northwest plants in search of general cytotoxic activity. Strong toxicity (LC₅₀ < 100 µg/ml) was found for 17 extracts from 13 species, with highest activity observed for Angelica arguta roots at <10...
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...
Four root mutants, diageotropica (dgt), and altered root architecture (ara) 1, 2, and 3, were used to study root architecture and better understand the process by which root architecture is determined. Adventitious root formation, tissue response to auxin, nutritional response, and starch accumulation in the leaves were tested in ara...
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Tomato
Kelsey Hoth1
Dr. Maria
Ivanchenko2
GENETIC ANALYSES
OF ROOT SYSTEM
DEVELOPMENT IN THE
We examined how the experiences of World War II and Korean War veterans,
including prewar, warzone, and postwar factors, affected PTSD symptoms in later life.
This dissertation consists of two studies. In Study 1, four different hypotheses from a
lifespan approach were examined (King et al., 1996): stress evaporation (only...
This thesis focuses on two aspects of transparent electronics, SnO₂ transparent thin-film transistors (TTFTs) and transparent circuits. Both depletion- and enhancement-mode SnO₂ TTFTs are realized. The maximum effective mobility for the depletion- and enhancement-mode devices are 2 cm²V⁻¹s⁻¹ and 0.8 cm²V⁻¹s⁻¹, respectively. A variety of techniques to decrease the carrier...