Gas exchange, leaf area development, leaf anatomy and stomatal characteristics of four tall fescue selections differing in forage yield were examined to provide further insight into characteristics associated with yield differences of these selections. Winter-growing TFM 26 and TFM 16, the highest and lowest-yielding selections, respectively, and summer-growing selections TFK...
Finite order autoregressive models for time series are often
used for prediction and other inferences. Given the order of the
model, the parameters of the models can be estimated by least
squares, maximum likelihood, or the Yule-Walker method. The
basic problem is estimating the order of the model. A number...
The presence of feedback in an inputoutput system
associated with an oceanographic phenomenon is determined. A
testing procedure to determine the presence of feedback is given.
The ordinary transfer function model is determined not to be
appropriate in modeling the system. The two and three stage least
squares methods are...
Geostatistical linear interpolation procedures such as kriging require knowledge of the
covariance structure of the spatial process under investigation. In practice, the covariance of the
process is unknown, and must be estimated from the available data. As the quality of the
resulting predictions, and associated mean square prediction errors, depends...
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...
Much of our knowledge about transgender (folks who identify as not cisgender) lives in universities centers around barriers experienced, feelings of exclusion, and being victims of harassment and violence. This thesis describes conversations regarding captured gender euphoric moments from five students at a large university. They came together through a...
This study surveyed a sample population of manufacturing companies in Oregon. Respondents were surveyed concerning their perceptions of ergonomics and their use of ergonomic consulting services from three potential sources of ergonomic consulting services. The sources of ergonomic consulting services were the Oregon Occupational Safety and Health Administration (OR-OSHA), Workers'...
These essays are an attempt to rebuild memories that explore the nature of work and family. They explore how work knocks against the joints of the body and against the joints between family members, and, as time passes, how the next generation inherits the family line of work only to...
Given the many significant roles that bacteria play in modern food manufacturing, it is crucial that we have a fundamental understanding of how bacterial communities assemble and behave in the food manufacturing environment. The focus of this dissertation was to investigate both the spatial and temporal distributions of microbial communities...
Vibrio parahaemolyticus infections in the United Stated have been linked to consumption of raw shellfish, particularly oysters, with symptoms of headache, abdominal pain, nausea, diarrhea, vomiting. Depuration, as a post-harvest process, has a long history of being applied in shellfish industry to reduce sewage bacteria. In order to reduce the...
Flavored milk is a growing category for dairy products; however, it is a perishable product that is subject to microbial spoilage which can lead to a negative consumer experience and lead to lost sales. Flavored milk processors communicated unique spoilage events related to their products, including color loss of strawberry...
Pasteurization is an effective method of reducing risks associated with foodborne pathogens in raw milk. Cheese made from raw milk has a higher potential to harbor harmful bacterial pathogens. However, some cheesemakers prefer to use unpasteurized milk to preserve the natural microflora present in the raw milk and to prevent...
Tomato seedlings were used to assay the population of A.
tumefaciens in artificially contaminated soil. Aqueous soil suspensions
were applied directly to the wounded stem. The bioassay was
used because not all pathologically important physiological strains
of A. tumefaciens would grow on any of the selective media available.
This method...
The Producing for the Future project engaged thirty low-income youth in gardening and nutrition education, microenterprise activities, and participatory research during the 2011 and 2012 growing seasons. The intervention aimed to support community protective factors, build positive youth development, and enhance health outcomes through promoting skill-building and mentorship. The mixedmethods...
This study identified the skills necessary to successfully complete the
beauty culture program of Alberta. The (Alberta) beauty culture teachers (N =40)
were surveyed, with their responses being used to assess the perceived skills.
The instument, a 41 item survey, was established through the use of a
Delphi panel to...
Adolescence is a developmental stage marked by crystallization in individuals’ sense of identity (Erikson, 1994; Harter, 1999). Research on positive youth development stresses the ways in which thriving trajectories during adolescence contribute to positive lifelong outcomes (Lerner & Overton, 2008; Scales, Benson, & Roehlkepartain, 2011) A symbolic interactionism perspective (Mead,...
With over 175 million Americans visiting each year and the ability to create unique learning experiences, informal science institutions may play a greater role in climate change education in the coming years. As facilities in Oregon begin to incorporate climate science and solutions into their educational programming, effective communication across...
Three studies were designed to evaluate the promoting
effect of cyclopropenoid fatty acids (CPFA) on avian myeloblastosis
virus (AMV) infection in White Leghorn chickens.
In the first study effects on growth parameters, blood serum
and erythrocyte lipid composition of White Leghorn chickens
were investigated at 100 ppm and 300 ppm...
The purpose of this ethnographic study was to explore White, female teachers’ attitudes and perspectives towards their African American students, the Black/White Achievement Gap, and their teaching practice in regards to their students’ achievement, through the use of focus group discussions. The target group for this study was White, female...
Marine Protected Areas (MPAs) can be considered as one of powerful conservation tools of fishery resource management in the literature. However, due to continuing environmental awareness and mismanagement, the Philippine government has decentralized the power of legislation and management of its MPAs since the early 2000. This encouraged participation of...
This study describes the historical development of the Associate Degree Nursing Program at Portland Community College by women faculty leaders in a male-dominated organization. In-depth interviews of eleven participants were transcribed and analyzed. The participants gave a very rich description of this nursing programthus describing its culture. Six themes were...
Monstrous beings, or distortions of nature, were a tangible object of fear in the medieval and early modern eras. Aristotle, as a precursor to the scientists and magical practitioners of the twelfth century or the barber-surgeons of the sixteenth century, understood monsters to be human or animal beings deformed by...
This study aimed to determine the efficacy of baking to reduce bacterial populations (an unknown contaminant or Salmonella) in cookie dough. Baking conditions (time and temperature parameters) were selected based on conditions commonly used in industry. The first study (Chapter 2), “Baking as Validation for Control of Coliform Counts in...
The production of Cheddar cheese is a complex process with multiple potential sources of undesirable bacteria, including those that have negative impacts on product quality (spoilage organisms) and those that are used to evaluate sanitary conditions in the production environment (indicator organisms). The dairy industry commonly uses coliform bacteria as...
Water availability is a critical limiting element in semi-arid ecosystem productivity and presents particular challenges in Sahelian countries such as Senegal. The landscapes are characterized by the presence of two common semi-arid shrubs (Piliostigma reticulatum and Guiera senegalensis), both of which may be important hydraulic regulators in these water-limited ecosystems....
Rework is a common practice in the dairy industry as a way for processors to minimize waste while recovering costs for dairy products that are unsaleable. The regulations available for reworking fluid dairy products only outline product eligibility requirements with a focus on repasteurization of the products containing rework as...
Foodborne outbreaks involving fresh produce have been on the rise since the late 1990's. Pathogens such as Salmonella spp. and Escherichia coli are prevalent in agricultural environments and commonly travel between farms via irrigation water. The Food Safety Modernization Act (FSMA) has placed an increased emphasis on microbiological standards of...
Multiple outbreaks of foodborne illness (Salmonella and E. coli O157:H7) have been associated with tree nuts and tree nut products since the early 2000s. In response to these outbreaks and many others in fresh produce and peanut butter, Congress created and passed the Food Safety Modernization Act (FSMA) to require...
2020 and 2021 brought the first reported outbreaks of salmonellosis epidemiologically linked to dry bulb onions in the United States. Outbreak investigations were not able to implicate a specific source of the contamination but speculated that contaminated water was a significant contributor. The Produce Safety Rule established minimum standards for...
Reports of foodborne outbreaks have increased in the last decade, posing a public health risk to consumers. In an attempt to mitigate this risk, the newly established Food Safety and Modernization Act (FSMA) takes a preventive rather than reactive approach to food safety. Under FSMA, producers are required to validate...
United States Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) guidelines for beef jerky processing support producers' ability to satisfy the performance standard requirements for achieving a 5-log reduction in Salmonella and E. coli O157:H7. The first compliance guide for jerky processors was created in response to several Salmonella outbreaks...
Butter has long been the premium choice for producing pastries such as Danish and croissants. Its inclusion has consistently delivered characteristically light and airy crumbs with beautifully flaky crust. Once considered a delicacy, pastries have now become innocuous in our everyday lives. Once requiring a skillful hand to sculpt and...
Salmonella is a bacterium responsible for several illnesses, including typhoid fever,
paratyphoid fever, and salmonellosis. It is commonly found in animal products, including
poultry. Determination of potential reservoirs of Salmonella contamination is important
to mitigate the risk of transmission and possible outbreaks. Outbreaks can negatively
impact the livelihood of local...
This investigation was designed to determine the extent to which
students who are completing planned curricula in mathematics education
are proficient in spatial visualization abilities and possess mathematical
understandings. The effects of mathematics curricula upon
the development of these abilities and understandings and the relationships
between these abilities and understandings...
Foodborne illness in the United States continues to be a complex and recurring issue despite our increased understanding of the pathogenic microorganisms responsible. Foodborne illness outbreaks and product recalls linked to pathogenic bacteria have been more frequent in the produce industry (e.g. fruits and vegetables) in the last ten years....
Non-starter lactic acid bacteria (NSLAB) are found at low levels in fresh raw milk and are important to the dairy industry because of their potential impact on the flavor and texture of yogurt, sour cream, and cheese. The purpose of this study was to evaluate three methods for the identification...
Listeria monocytogenes is the third most deadly foodborne pathogen in the United States. The young and elderly, as well as pregnant and immunocompromised people are the population most susceptible to serious illness and death from listeriosis infections.
Unlike most foodborne pathogens, L. monocytogenes does not live a solely enteric lifestyle....
I offer a personal and prehistoric exploration of the concept of immanence, the principle of a divine force living, remaining, and operating within living creatures, inherent in the human, including the female; a unifying force that connects humans to each other, to nature, and to the earth. I examine the...
Listeria monocytogenes contamination continues to pose challenges for the food industry and there is demand for effective methods of food preservation and protection that can also be considered clean label. A promising source of antilisterial compounds may be sourced from bacteria that produce novel byproducts. Ribosomally synthesized and post-translationally modified...
Bloomy rind cheeses, including Camembert and Brie type cheeses, are highly susceptible to contamination by environmental pathogens during their manufacture and ripening. These cheeses undergo many physiochemical changes during ripening that provides these pathogens with a suitable environment to grow. One example of this change is an increase of pH...
Recent studies have discovered that salmon, specifically juvenile Coho Salmon, have their olfactory senses inhibited by the presence of low concentrations of copper concentrations at very low concentrations. Much of this copper is deposited on roadways by car brake pads during their use. The copper is carried with stormwater into...