Recently, fiber-reinforced plastics (FRP lamina) have
been applied to glued-laminated (glulam) timber for the
purpose of improving bending strength and stiffness.
Initially, full length reinforcement using FRP lamina was
developed. However, the cost of FRP lamina is a significant
portion of the total cost of reinforced glulam. Therefore,
it is...
Agricultural production in the Sahelian region of Africa is
among the lowest in the world. Cyclical infestations of locusts and
grasshoppers have contributed to this low productivity. The infestations
appear to be triggered by heavy rainfall at the beginning of a crop season
after extended drought. Because locusts and grasshoppers...
The objective of this study was to determine if supplementing linoleic or α-linolenic acids, and timing of supplementation around AI will alter supplemental intake, ADG, and serum progesterone (P4), cholesterol, and triglyceride concentrations in replacement Angus crossbred heifers. In yr 1, 54 heifers, stratified by age, were assigned to: barley...
Feeding conjugated linoleic acids (CLA) improves reproductive performance in dairy cows; however, the molecular mechanisms by which CLA improves reproduction are not well understood. Therefore, we evaluated whether the CLA isomers, trans-10, cis-12 CLA and cis-9, trans-11 CLA altered synthesis of steroidogenic hormones in bovine luteal cells by measuring concentrations...
Habitat for pollinating insects is declining, which is a concern for agricultural communities that rely on pollination services. Meanwhile, solar energy development is increasing as communities seek to source energy renewably. Land under solar panels is traditionally unused, so some communities are planting pollinator habitat under solar panel canopies to...
Experiments focusing on plant growth regulators’ concentrations and combination, mineral salt formulations and TDZ pretreatment formations were conducted to optimize in vitro shoot regeneration from leaf and petiole explants of 'Marion' blackberry. Optimum shoot formation was obtained when stock plants were incubated in TDZ pretreatment medium for three weeks before...
In recent years, there has been renewed interest in black raspberry (Rubus
occidentalis L.) breeding. This has been spurred, in part, by an increase in black
raspberry consumption due to studies that have shown them to be particularly high in
anthocyanin content indicating high levels of antioxidants. Present cultivars are...
Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made...
Lower atmospheric flux measurements are a difficult subset of atmospheric data to accurately collect. The interplay of cost, precision, specialty, resolution and repeatability compound an already difficult experimental problem. In response to this, a new, novel instrumentation approach to measuring within the atmospheric boundary layer (ABL) is introduced.
The combination...
Rapid increasing of renewable energies and the knowledge about their environmental effects are very limited. As a result, the renewable energies (e.g. solar or wind energies) will play a vital role in the future because it is well accepted by environmental friendly industries. This dissertation presents the modeling, data analysis...
Purebred Jersey steers are often overlooked for beef production due to the perceived poor growth and production. Currently dairy persons marketing their steer offspring are receiving minimal compensation due to lack of demand by beef feeders and a saturated veal market. Twenty purebred Jersey steers were used to evaluate lifetime...
Agrivoltaic systems promote dual use of land by combining solar energy and agricultural production. Grazing sheep in these systems is popular but research on intentionally designed pastures to increase production is lacking. This study seeks to compare the herbage growth and lamb production in simple, diverse, and legume pasture mixes...
Resilient water, food, and energy management strategies for an ever-growing population and changing environment depends on our understanding of water and carbon cycles from local to global scales. Fluxes of water and carbon are coupled by photosynthesis and plant transpiration cycles the largest fraction of terrestrial water from the land...
Hydraulic conductivity of hemp stems under water-stress conditions was investigated. When plants face with water-stress conditions, embolies (cavitation) are triggered in xylem channels and water transport from the root to the leaves is affected. The relation between percentage loss of water transfer ability within the xylem channels can be described...
We have sufficient evidence that our historical management of natural resources is not sustainable. Food production is stagnating or declining. Nonrenewable energy sources on which the energy sector has historically depended are being rapidly depleted. Water resources, for which the energy and food sectors compete, are being depleted and impaired....
Growing populations and industrialization rates across the world are leading to increased food and energy demand. The challenge of meeting this demand while also mitigating climate change impacts serves as a driving force for the development of renewable energies technologies. This study focuses on the role of Agrivoltaic systems in...
Atmospheric pressure changes do not stop at the permeable snow surface but rather propagate into it. These pressure changes range from high-amplitude, low-frequency events caused by seasonal cycles and synoptic weather systems to small-amplitude, high-frequency events caused by topographic features and turbulence. The effect of pressure changes on interstitial air...
The first part of the dissertation chronicles irrigation technology changes to progressively improve water application efficiency, water use efficiency, irrigation water productivity and crop production. Technological innovation in irrigation, from 6000 BC to present, has been driven by an unchanging need to provide support for growing populations. The first irrigation...
Strawberry is one of four crops included in the USDA-NIFA Specialty Crop Research Initiative-funded RosBREED project along with apple, peach, and cherry. Phenotyping strawberry for specific horticultural and commercial traits is important to identify associations with genotypic marker(s). This process is the first step in translating genomic knowledge into enhanced...
Nuclear DNA flow cytometry was used to differentiate ploidy level and determine nuclear DNA content in Rubus. Nuclei suspensions were prepared from leaf discs of young leaves following published protocols with modifications that included: increasing the stain concentration, adding the stain after the RN ase treatment instead of adding it...
The Warm Springs Reservation is located in central Oregon. Livestock production consists of beef (commercial with an Angus, Horned Hereford base) and roping (Corriente and Longhorn) cattle and horses that forage most of the year on the open range within reservation boundaries. Forage consists of annual and perennial grasses and...
In recent years, there has been renewed interest in black raspberry (Rubus occidentalis L.) breeding. This has been spurred by an increase in black raspberry consumption due to studies that have shown them to be particularly high in anthocyanin content indicating high levels of antioxidants. Present cultivars are ill adapted...
Precision irrigation has made spatially explicit water management a reality. However, detailed knowledge about the spatially variable evapotranspiration is often unavailable. One example location where we can begin to understand the impact of spatial variability on evapotranspiration is at the field edge, which contains a sharp discontinuity in surface conditions....
Agrivoltaics, which integrates photovoltaic power production with agriculture in the same plot of land, has the potential to reduce land competition and crop irrigation. To optimize agrivoltaic systems for crop growth, energy pathways must be characterized. While solar panels shade the crops, they also emit longwave radiation. At the end...
Lake Chad is a vitally important wetland in the semi-arid Sahel corridor. It provides the basis of many thousands of livelihoods which depend on its seasonal fluctuations to renew fish stocks, farmland and rangeland. This paper describes how the institutions which govern access to fishing rights has evolved on the...
Satellite Based evapotranspiration (ET) models have become a dominant means to estimate large-scale surface fluxes of water. Global and regional ET estimates are important parameters in many climate forecasts and hydrologic models. However, large scale partitioning of ET into soil evaporation, transpiration, and canopy interceptions remains largely unknown and modeled...
Vibration of nuclear power plant components can cause fretting wear and fatigue that can eventually lead to component failure. Flexible, high-aspect ratio components under flow, such as the wire-wrapped cylindrical fuel elements in a liquid metal-cooled fast reactor (LMFR) core, are particularly susceptible to vibration due to their low natural...
Forest disturbances, such as wildfires, pine beetle outbreaks, and floods are important features of many landscapes and ecosystems. Many disturbances are increasing in size, frequency, and intensity due to changing climates and land management decisions. The changing ecological and aesthetic conditions following a disturbance can lead to negative short- and...
This work is a culmination of a series of published works related to the use of the Material Point Method (MPM) in modeling wood adhesive bonds. The use of wood as construction material has the potential to play a small role in the solution to the current CO2 and climate...
Athletic activities have always carried an inherent risk for injuries, and basketball is no
exception. Basketball is the second most popular team sport in the United States in
which 984,777 high school boys and girls participated during the 2010-2011 season.
Athletic trainers and strength and conditioning staff are pressured to...
Laser ultrasonics can be used to nondestructively evaluate structures to determine the existence and location of surface and interior flaws. The goal of this research was to determine if laser ultrasonic techniques can be applied to the inspection of aluminum plate. titanium tubes, and large welded plate structures. The research...
Increasing the abundance of salmon in coastal Oregon rivers and streams is a high priority public policy objective. Salmon runs have been reduced from pre-development conditions (typically defined as the 1 850s), but it is unclear by how much. Considerable resources have been allocated to restoring salmon runs, but it...
Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The University of Wyoming joined this collaborative effort in January 2010, and the National Wind Coordinating Collaborative joined the effort in March 2011. The...
The residual of the surface energy budget is represented as the linearized sum of energy losses due to storage, advection and flux underestimation. Individual contributions to the residual can be quantified through constrained multiple linear regression which identifies the site specific processes that are responsible for the lack of energy...
Some evidence suggests a connection between outdoor recreation participation and
stronger environmental worldviews. This study finds little evidence supporting
participation in outdoor recreation activities and stronger environmental worldviews and
some evidence supporting a weak connection between appreciative outdoor recreation
and stronger environmental worldviews. Additionally, the study documents greater
participation in...
Environmental scientists, land managers, and policy actors are increasingly presented with high-stakes high-uncertainty problems stemming from human-ecosystem interactions. To help address these problems, scientists frequently use models that produce enormous geospatial and temporal datasets that are constantly modified and often seek input from communities outside their discipline. To assist scientists—as...
This thesis pursues a flexible understanding and definition of
dis/ability as a broadly and liberally applied mark of stigma. It asks questions that develop a deeper understanding of how disability influences mētis, a knowledge or cunning use of the body. Through this framework of mētis, this thesis explores technologies as...
Renewable energy is a topic of significant interest and importance in the world today. Ocean wave energy, particularly in areas such as the Oregon Coast, has considerable potential as a renewable resource. However, to rightly evaluate the overall cost of energy for wave energy converters, survivability and maintenance issues must...
All streams in Oregon that are inhabited by salmon and trout have a statemandated
water temperature standard. However, temperatures of many streams,
especially during summer months, exceed the seven-day average maximum
temperature parameter (200 C for redband trout inhabited streams) accepted by the
Oregon Department of Environmental Quality. To date,...
Red tree voles (Arborimus longicaudus) are a unique species of Arvicoline rodent found in western Oregon and northwest California. Their preferred habitat is mature and old-growth coniferous forest dominated by Douglas-fir (Pseudotsuga menziesii). Tree voles are an important prey item for northern spotted owls and many other predators, but are...
Recent catastrophic wildfires have forced the forest management community to develop new strategies for reducing forest fuels. Tightly spaced understory trees often create a fire ladder allowing surface fires to encroach into the crowns of overstory trees. This situation can lead to intensive, catastrophic, stand-replacement forest fires. Mechanical removal or...
Livestock grazing has been indirectly related to sage-grouse (centrocercus
urophasianus) declines in the western United States and southern Canada; however,
there is a lack of scientific research that directly relates the two. Our objective was
to investigate the influence of livestock herbivory on sage-grouse nesting habitat by
determining the spatial...
Understanding the interplay between energy and water is central to effective natural resource management. With enough energy it is possible to secure sufficient water, with enough water it is possible to produce nearly boundless energy. The sun is the engine which drives the availability of both these resources; nearly every...
Within the sagebrush steppe ecosystem, invasive annual grasses are of growing management concern as they outcompete native vegetation, change the fundamental nutrient cycling processes, decrease biodiversity, and increase frequency of wildfires. The most widely used and effective management tool to decrease invasive annual grass abundance, is the use of pre-emergent...
Strawberry is economically the most important berry crop grown worldwide and breeders are continuously striving to develop improved cultivars. So far, marker assisted breeding (MAB) in strawberry has been limited to the private sector. However, loci controlling some traits of economic importance such as perpetual flowering (PF) and soluble solids...
The knowledge about the intensive agricultural irrigation is very limited, but the use of irrigation is rapidly increasing. As an outcome, the sympathetic ecosystem is accepting modern irrigation that will play an essential function in the present and future for agricultural products. My dissertation will display the modification for investigation...
This dataset was used to determine the attenuation of an audio signal by reticulated foam samples that span the natural range of intrinsic permeability for seasonal snow. Data are audio measurements acquired on a two-channel oscilloscope.
This dataset was used to determine the attenuation of an audio signal by reticulated foam samples that span the natural range of intrinsic permeability for seasonal snow. Data are audio measurements acquired on a two-channel oscilloscope.