The teliospore of Tilletia caries germinates to produce a promycelium
with a whorl of primary sporidia at its tip. The time between
emergence of the promycelium and the development of primary sporidia
averaged 2.3 h. Fusion between compatible sporidia occurred within
an additional 3.8 h. Primary sporidia appeared to be...
The genus Lichnanthe Burmeister contains eight extant and one
fossil species which are strictly nearctic in distribution. The
subfamily Glaphyrinae, however, is distributed nearly world-wide.
Five species were previously described and three are described as
new herein. All eight extant species are described in detail herein,
synonomies are made current,...
Soil samples and soil clods were collected from ten potato fields
in Eastern Oregon. An index of grain size distribution was sought that
would correlate well with compacted soil bulk density. The Hazen
coefficient of uniformity was best related to bulk density. The
limitations of various indices and their relationship...
The response of sweet corn (Zea mays L. var. rugosa cultivar
Jubilee) to 12 populations and four nitrogen rates was studied in a
field experiment. Populations ranged from 43, 904 to 329,800
plants/ha with nitrogen levels ranging from 0 to 224 Kg/ha. A systematic
spacing design was used. Plant height,...
This study presents potential Low Impact Development (LID) solutions for the Ash Creek watershed and designs several tools to assist localities in implementing the solutions they may choose. Ash Creek is a tributary of the Willamette River flowing through Dallas, Monmouth, and Independence in Polk County, Oregon. Currently, Ash Creek...
Field, greenhouse, growth chamber and laboratory experiments
evaluated factors affecting establishment, survival and production
of birdsfoot trefoil (Lotus corniculatus L.) and alfalfa (Medicago
sativa L.)
Field studies investigated the effects of a barley companion
crop, seedling year harvest management and nitrogen and phosphorus
fertilization upon stands, survival and subsequent production...
Temperature and water potential effects on the growth,
transpiration, total nonstructural carbohydrate (TNC) content, and
nutrient uptake of sudangrass (Sorghum vulgare var. piper) were
investigated in laboratory experiments. The effect of nitrogen supply
on the growth and nutrient uptake at constant soil water potential was
also investigated in this study....
The Northern Rubber Boa (Charina bottae) is a small, secretive boa native to the Pacific Northwest. Despite this being possibly the highest latitude boas and one of only two boas native to the continental U.S., it has received surprisingly little attention. Most of the research on the natural history of...
Starch is a significant component of the human diet and the glucose produced through its digestion provides a critical source of energy. When starch enters the mouth, salivary α-amylase hydrolyzes it into maltooligosaccharides (MOS, degree of polymerization [DP] 3-20) and maltopolysaccharides (MPS, DP >20). Previous studies have found that humans...
Relative to visual and audible communication, haptic perception is quiet, does not require eye contact, can be applied at any point on the human body, and can function in parallel with the other four human senses. Vibrotactile feedback is a method of haptic communication using vibrations applied to the skin....
Managing agricultural diversity ensures a range of public services, such as genetic resource diversity, food security for subsistence-based economies, and landscape resilience in the context of climate change, among others. These agrobiodiversity conservation services are positive externalities from agrobiodiversity conservation. Whereas their value is not captured in market transactions, management...
Prebiotics are a subset of dietary fiber that is growing in demand within the food industry. The health benefits of prebiotics have been well established, leading to the increase in its incorporation into various food products. Given the importance of prebiotics as functional ingredients, it is important to understand their...
The purpose of this study was to understand the vulnerability and adaptive capacity of shellfish stakeholders in the Pacific Northwest who are adapting to ocean acidification (OA). This study developed a geovisualization tool of existing environmental data for assessing species-specific risk profiles to OA (based on their exposure and sensitivity),...
Urban parks are biodiversity hotspots within cities and have the potential to provide a range of socio-cultural benefits for people, but may not always meet the needs and desires of park visitors. A variety of land use practices and environmental factors affect urban park biodiversity and vegetation structure, composition, and...
A fundamental objective of ecology and population biology is to identify factors that drive population dynamics and determine the population-level consequences of their interaction with the environment. Studies of reproductive performance can illuminate population dynamic processes, including the links between organismal biology, the environment, and life history theory. A central...
Modern plant pathology benefits from integrating methods and concepts from evolutionary biology. For example, evolutionary concepts are used to identify and examine species boundaries of plant pathogens, recognize processes underlying pathogen biogeography, identify traits that characterize emerging species, and discover new molecular interactions that originate under processes of selection. In...
The current rate of global biodiversity loss and extinctions is unparalleled and a major concern. Freshwater organisms are facing particularly rapid rates of biodiversity loss. Amphibians, which require an aquatic environment for part of their life cycle, are one of the most vulnerable vertebrate groups. Amphibians are experiencing population declines,...
The design of programming tools is slow and costly. To ease this process, we have developed a design pattern catalog aimed at providing guidance about how to design tools for developers. This guidance is grounded in Information Foraging Theory (IFT), which empirical studies have shown to be useful for understanding...
In contrast with other Odocoileus species, Columbian black-tailed deer (Odocoileus hemionus columbianus) population dynamics are not well understood throughout the species’ range. Concerns over apparent long-term population declines have prompted efforts to fill basic knowledge gaps including estimates of vital rates (fecundity, recruitment and survival) and cause-specific mortality. The Oregon...
Northern highbush blueberry is a long-lived perennial crop that is well adapted to low soil pH conditions. The plants are often shallow rooted and absorb primarily the ammonium (NH₄) form of nitrogen (N) rather than nitrate-N (NO₃-N). Traditionally, commercial blueberry fields have been irrigated with overhead sprinklers and fertilized using...
Current product design methodologies are not conducive to creating inclusive products (products that meet the needs of persons with and without disabilities). In order to reduce the effort and expense involved in creating inclusive products, empathic design principles are applied to discover whether customer needs for people with disabilities can...
A study was conducted on German velvetgrass (Holcus mollis L.), a weedy, rhizomateous perennial grass introduced in the
United States in relatively recent years, The purpose of this study
was to learn more about its distribution, growth habits, and control
under conditions found in Western Oregon. German velvetgrass infestations of...
One of many important physical properties that must be known
to understand transport phenomena in soils is pore size distribution.
Presently the pore size distributions of soils are most commonly
obtained from soil water characteristic curves. The soil water characteristic
curves are usually obtained by the pressure plate technique.
It...
Investigations were conducted to (1) determine the original
pattern of deposition and thickness of ash in the Ochoco and Blue
Mountain areas of Oregon, (2) determine if discontinuities exist in
the parent material of these soils, (3) determine the degree of mixing
of ash with other materials and evaluate reworking...
Three levels of dietary crude protein (8.6, 11.4, and 17.2) were
fed to 24 pony mares to determine the effects on the estrous cycle,
conception rate, and serum progesterone concentrations. Mares were allotted into three treatment groups designated as low protein (LP),
medium protein (MP), and high protein (HP). Following...
Twenty-one rice cultivars were evaluated to determine the difference between populations of Sogatodes oryzicola (Muir) (Homoptera: Delphacidae) in Costa Rica and Colombia, Survival, mortality and population development of S. oryzicola on five selected cultivars was used to determine levels of plant resistance. The importance and potential of the parasitoid-predator Haplogonatopus...
Intensive cultivation of Walla Walla silt loams (coarse silty,
mixed, mesic, typic Haploxeroll) in eastern Oregon and Washington
during the past 50 years, has decreased internal soil drainage in
the 15 to 40 cm layer. However, no measurements have been made to
determine the causes and corrective management for this...
A MOS biquadratic (biquad) filter employing the switched-current technique is
reported. The circuit uses current-mode processing which can offer wide
bandwidth, low voltage operation, and can be implemented with standard CMOS
technology. Examples of lowpass, highpass, and bandpass filters are given
which illustrate the synthesis procedures and the versatility of...
On January 8th, 2011 tragedy struck in Tucson, Arizona. A gunman opened fire on Representative Gabrielle Giffords' "Congress on Your Corner" event, wounding thirteen and killing six ("Arizona Shooting"). Four days later, President Obama spoke to a grieving crowd at the University of Arizona's McKale Memorial Center. This study seeks...
Popcorn was popped conventionally in oil and in a microwave
oven without oil. Volatile components were collected by condensation
of popper headspace gases and by vacuum steam distillation of
a slurry of ground, popped corn in distilled water. The organic
compounds were extracted from the aqueous condensate and vacuum
distillate...
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a
worldwide pest of numerous agronomic and horticultural plants. Conservation
biological control of this pest can be unreliable due to asynchrony of natural enemies
and certain horticultural practices that have a direct or indirect affect on natural
enemies and the...
A cost function characterizes a firm's cost-minimizing behavior. It is defined
as a function of the level of outputs produced and the prices of factors which enter
the production process. Econometric estimation of a cost function allows one to test
hypotheses regarding the structure of cost and the structure of...
High yield unbleached kraft pulp for linerboard and bag paper
was deshived in a PFI mill and a Bauer model 187 double disk refiner.
Levels of plate gap, specific energy consumption, throughput rate,
and stock consistency were varied to control PFI mill and Bauer 187
deshive refining. Shive content reductions...
Nonlocal theories of continuum mechanics are used to model the
fracture behavior of particleboard in tension perpendicular to the plane
of the board. Classical theories of fracture are examined in comparison
to a nonlocal crack solution which has removed the stress singularity
at the crack tip. With the removal of...
Thinning of young Douglas-fir forests has the potential to enhance structural diversity and improve habitat for wildlife. I examined the effects of thinning and thinning intensity on abundance and demographic characteristics of forest-floor small mammals in the Coast Range of Oregon 5 and 6 years after thinning had occurred. Thinning...
This research focuses on the relationship between the emerging role of land trusts and
rapid growth and change in the West. Teton County, Idaho, Teton County, Wyoming, and
Sublette County, Wyoming, and each of their associated land trusts, are used as case studies. Each county has experienced varying levels of...
The goal of this analysis is to use the social construction framework to determine 1) whether the Oregon Drug Take Back Program stakeholder group can design a public policy that will ultimately reduce water contamination from the improper disposal of unused pharmaceuticals from the general public, and 2) use the...
Environmental stress can negatively affect the ability of organisms to reproduce. Energetic trade-offs exist in all organisms, and under stress, energy may be allocated away from reproduction and towards physiological defense and repair mechanisms. The rocky intertidal environment is ideal for investigating the influence of environmental stress, as organisms are...
Structure-property relationships have always underpinned the field of solid state chemistry; dependable structural descriptions are integral to understanding and controlling the physical properties of inorganic compounds old and new. While a handful of crystal structures are celebrated for their versatility, flexibility, and functionality, the existence of more exotic structures is...
Experiments were conducted to determine the effect of environment
and several plant growth regulators on the physiology, quality,
and agronomic performance of snap beans (Phaseolus vulgaris L. )
and spring wheat (Triticum aestivum L. ). The potassium salts of
naphthenic acid and cyclohexanecarboxylic acid, received particular
attention.
Application of potassium...
The reproductive performance of four strains of broiler breeder
males (BBM) were compared when housed in individual cages from 22 to
56 weeks of age (WOA), and fed Asi libitum 7% crude protein (CP) diets
with 1985, 2424, 2868 kilocalories (kcal) metabolizable (M) energy (E) per
kg of feed and...
Two methods of separating sugars and acids of Bartlett pears
were compared to decide upon a working method for later studies
involving identification and quantitation of sugars and acids during
ripening of pears and in the production and storage of pear concentrate.
The first method involved precipitation of acids with...