The purposeful induction of malolactic fermentation (MLF) in wines such as Pinot Noir and Chardonnay is an established commercial wine making practice in Oregon. This induction is not always successful, especially with white wines, such as Chardonnay. A study was initiated to examine the compatibility of yeasts commonly used in Oregon winemaking with various strains of malolactic bacteria. In preliminary and pilot plant scale experiments, the yeast strain found to be most conducive to malolactic fermentation by lactic acid bacteria was Montrachet (Red Star). The malolactic bacterial strains that were best able to complete malolactic fermentation in various wines, fermented by different yeast strains, were the two Oregon commercial strains, ER1A and Ey2d, and the Pinot Noir juice isolate, DAPN85A. Sensory analysis of aroma by difference from control test was done on Chardonnay wine fermented by 4 different yeast strains and 3 different malolactic bacterial strains. In all cases, there was an overall significant difference in malolactic fermented wine aroma when compared to control wines. Organic acid analyses by high pressure liquid chromatography (HPLC) and analyses of volatile compounds by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were done on selected Chardonnay wines. Propionic acid was found to diminish in malolactic fermented wines while acetic acid content increased. Isobutanol and isobutyraldehyde increased significantly in MLF wines, compared to the controls. Chemical analyses of MLF and control wines suggested two possible chemical reactions resulting from the MLF. The first was the reduction of isobutyraldehyde to isobutanol, and the second was the hydrolysis of isobutyl acetate to isobutyraldehyde and acetate. On all GC chromatograms of wines, where MLF had occurred, there was an unidentified peak close to the retention time of isoamyl acetate. This peak was not evident in wines where MLF had not occurred. Eight compounds were tentatively identified by GC-MS in malolactic fermented wines which were not found in the control wines. These were 4-methyl-3-pentanoic acid, methyl acetate, ethyl hexanoate, hexyl acetate, 1,12-tridecadiene, hexadecanoic acid, and a compound which was tentatively identified as farnesol, or 1,2-benzenedicarboxylic acid. The latter four compounds had identity fits of less than 900 from the mass spectral analysis. Whether any of these eight compounds match the unknown "ML peak" found in the GC chromatograms is unknown. / Graduation date: 1989

The composition and some qualitative aspects of ground beef offered for sale in Corvallis, Oregon were studied. Samples were purchased from six retail markets twice weekly throughout a six week test period. Three stores were independently owned and operated and three were chain stores. Differences in moisture, fat and protein levels of ground beef samples among the six stores and between chain and independently owned stores were statistically significant. Differences in composition between sampling days (Tuesday versus Friday) and between replicate weeks were generally not significant. Ground beef from chain stores was generally characterized by higher moisture and protein levels and lower fat levels. Thirty-two percent of all samples (50 percent of the independent stores and 14 percent of the chain stores) exceeded the legal limit of 30 percent fat. Moisture:protein ratios ranged from 2.53 to 4.24 while the average value was 3.59. About 28 percent of all samples had ratios in excess of 3.70. Differences in moisture:protein ratios between chain and independent stores were not significant. Although differences in extract-release volume (ERV) of ground beef obtained from the various stores were significant, differences between sampling days, replicate weeks and chain versus independent stores were not. Resazurin reduction times of ground beef among individual stores, between sampling days, replicate weeks and chain versus independent stores were not significantly different. The correlation between ERV and resazurin reduction time was low (r = 0.21) suggesting a poor relationship between these two procedures for assessing microbial contamination in ground beef. Differences in nonprotein nitrogen (NPN) levels of samples among stores and between sampling days were statistically significant. Only minor differences in NPN levels between store types and replicate weeks were observed. Soluble protein levels appeared to be a reflection of total protein. Iodine numbers of ground beef fat ranged from 43.7 to 53.6 and were significantly higher in ground beef purchased from chain stores. Price per pound of ground beef and price per pound of protein were significantly different among the six stores. The price per pound of meat was significantly higher in the chain stores than in the independent stores. However, price per pound of protein and price per pound of soluble protein were essentially the same for the two types of stores. Recommendations for quality control of ground beef sold at the retail level are discussed. / Graduation date: 1968

No description available.

Volcanic tuffs and tuffaceous sediments are frequently associated with elevated As groundwater concentrations even though their bulk As contents (~ 5 mg kg-1; Savoie, 2013) are only marginally greater than the average crustal abundance of 4.8 mg g-1 (Rudnick & Gao, 2003). Thus, As mobilization must be facilitated by conditions particular to these rocks. Alkaline desorption, anionic competition, reactive glass dissolution, and reductive dissolution of iron oxides are proposed processes of As release from volcanic rocks. Geogenic As contamination of groundwater in the southern Willamette Valley in western Oregon has been well-documented since the early 1960s, and previous studies have identified the Little Butte Volcanics Series and Fisher and Eugene Formations as the source of As contamination. This study examines 19 samples from 10 units of ash flow tuffs and tuffaceous sediments within the Fisher Formation and Little Butte Volcanics Series, representing a range of weathering and devitrification, to determine conditions of mobilization and mineralogical constraints that control As release into solution. Leachate studies were conducted over a range of pH from 7 to 11, phosphate concentrations from 10 μM to 100 mM, and in time series from 4 to 196 hours. Results demonstrate that silicic volcanic tuffs are capable of mobilizing As in concentrations above regulatory limits at pH conditions produced naturally by the tuffs (pH 8-9) or with moderate concentrations of P (10-100 μM). Alteration products, e.g. zeolites and clays, appear to be the primary host phases for mobile As. Samples that do not contain these alteration products tend to produce concentrations of As well below regulatory limits and often below the instrument detection limits of this study. The type of alteration may influence As mobilization: tuffs containing more clays tend to mobilize As through surficial desorption, and tuffs containing more zeolites tend to mobilize As by dissolution or formation of colloids. Additionally, one volcaniclastic sample demonstrates that extremely elevated concentrations of As, up to 1000 μg/L are possible as a result of oxidative dissolution of As-bearing sulfide phases.

This study contributed to the body of research that supports a holistic model of afterschool learning through the design of an afterschool intervention that benefits elementary school students of low socioeconomic status. This qualitative study evaluated a science focused afterschool curriculum that was designed using principles from Risk and Resiliency Theory, academic motivation theories, science core ideas from the Next Generation Science Standards, and used environmental education philosophy. The research question of this study is: how does an outdoor and STEM based afterschool program impact at-risk students' self-efficacy, belonging and engagement and ability to apply conceptual knowledge of environmental science topics? The study collected information about the participants' affective experiences during the intervention using structured and ethnographic observations and semi-structured interviews. Observations and interviews were coded and analyzed to find patterns in participants' responses. Three participant profiles were developed using the structured observations and ethnographic observations to provide an in depth understanding of the participant experience. The study also assessed the participants' abilities to apply conceptual understanding of the program's science topics by integrating an application of conceptual knowledge task into the curriculum. This task in the form of a participant project was assessed using an adapted version of the Portland Metro STEM Partnership's Application of Conceptual Knowledge Rubric. Results in the study showed that participants demonstrated self-efficacy, a sense of belonging and engagement during the program. Over half of the participants in the study demonstrated a proficient understanding of program concepts. Overall, this holistic afterschool program demonstrated that specific instructional practices and a multi-modal science curriculum helped to support the social and emotional needs of at-risk children.

This study draws on census data and geographic information systems (GIS) to investigate the relationship between light rail transit (LRT) infrastructure development and gentrification in Portland, Oregon. While recent research using comprehensive measures of neighborhood socioeconomic status (SES) supports a potentially causal link between transit development and gentrification, research into the effects of transit on property values alone tends to dominate the discourse. This study therefore seeks to build on previous research to develop an index measure of neighborhood SES and SES change based on measures of education, occupation, and income, using census data from 1980-2010. This multifaceted measure of neighborhood SES is analyzed in relation to LRT access using correlation, OLS regression, and GIS hot spot and choropleth mapping. Findings: Throughout the study period, low SES neighborhoods largely disappeared from the City of Portland, while low-income households were gradually priced out. Simultaneously, the easternmost suburb of Gresham became more highly concentrated in low SES neighborhoods. No definitive relationship between LRT and SES is found along the Eastside Blue or Westside Blue Lines, but strong evidence is found supporting a positive effect of Yellow Line MAX development on the rapid gentrification of North Portland from 2000-2010. Regressions run on neighborhoods along the Yellow Line indicate that SES change was greatest for those that began the decade with large Black populations, low rents, and close proximity to stations. Findings are discussed through the theoretical framework of the urban growth machine, which suggests the differential relationship between LRT and neighborhood SES relates to the distinct values of different parts of the region for the pursuit of general growth goals.

This study aims to shed light on several vexing questions surrounding marijuana at various levels of analysis. Why have some states adopted medical laws when others have not, and what are the implications of these adoptions for elites at the federal level? Why are certain areas within states hotbeds of marijuana use and production? Why, in the face of serious penalties, do certain individuals continue to use, produce, and sell this particular drug? How is the marijuana market structured and how much economic impact does it have? Possible sociopolitical factors responsible for passage (or failure) of marijuana-related voter initiatives and legislation in states are examined and the process of policy diffusion occurring between states that adopt such measures is detailed. An analysis of geographic variations in medical cardholder rates in Oregon is conducted using longitudinal data. Using a Respondent-Driven Sample and a detailed survey of legal and illegal marijuana users in Oregon, I identify differences between the two groups, elucidate differences between marijuana users and the general population, and estimate the economic impact of marijuana on Oregon's informal economy. Overall, the study finds that innovative, Democratically dominated states tend to pass medical marijuana laws and are the most at risk of doing so in the future. Within Oregon, county-level participation in the medical marijuana program is associated with Democratic party members, unemployment rates, and timber harvest levels. The Oregon marijuana market consists of a robust network of small producers, with individual users primarily managing distribution of the drug. Economic estimates indicate that the legalization of marijuana could generate between $37 million and $153 million per year in taxes for the state. Finally, historical evidence suggests that legalization of this drug could lead to its control; however, doing so could structurally transition the market from a robust network of small producers into tight oligopolic control by a limited number of producers, thereby disenfranchising small, artisan growers, communities traditionally reliant on marijuana for revenue, consumers who seek variety, and the plant's genetic diversity.

Hawk Rim represents a new mid-Miocene site in Eastern Oregon. This time period offers a rare chance to observe dramatic climatic changes, such as sudden warming trends. The site is sedimentologically and stratigraphically consistent with the Mascall Formation of the John Day Basin to the north and east of Hawk Rim. Hawk Rim preserves taxa such as canids Cynarctoides acridens and Paratomarctus temerarius, the felid Pseudaelurus skinneri, castorids Anchitheriomys and Monosaulax, tortoises and the remains of both cormorants and owls. Hawk Rim has yielded a new genus and species of mustelid. As individuals these taxa are of interest, but the real story is told by the paleoecology. The lower reaches of the section have lacustrine diatomite layers as well as preserved logs, suggesting the presence of a wet, forested ecosystem as conformed by the structure of the paleosols. Climate data allow us to make analyses of large-scale ecological trends in mid-Miocene Oregon.

From September 2009 to July 2011 I collected vertically stratified zooplankton samples and recorded estuarine water parameters on a monthly basis in the Coos Bay estuary, Oregon during flood and ebb tides. I identified five taxa of juvenile bivalves in the plankton:

The spatial distribution of chipped lithic artifacts excavated at site 35C05, a Chinookan plankhouse of the protohistoric period, was observed to test the hypothesis that a gradient of material culture -- reflecting social status -- should be evident within the plankhouse, ranging from the highest to the lowest social rank. Prior to the spatial analysis, use-wear analysis was used to evaluate the classificatory labels used to describe the assemblage by a previous researcher. The use-wear analysis largely confirmed the functional classification of chipped lithic artifacts used by the previous researcher. The spatial analyses revealed that while most tool types were rather evenly distributed throughout the plankhouse interior (taphonomic factors having been considered), cutting, graving and scraping tools (as well as some characteristics of these tools, such as raw material quality) were significantly unevenly distributed, correlating with the hypothesized gradient of social rank aligned with the long axis of the plankhouse. Further analyses strongly suggested that one or more labor specialists, using high frequencies of graving tools, were inhabitants of the elite portion of the plankhouse. Most domestic activities reflected by the stone tools of this assemblage were engaged in by plankhouse inhabitants of all social ranks. Knowing that this is the case, as well as that in some instances there is compelling evidence for status-determined labor specialization, aids in our understanding of the character of aboriginal social structure on the Pacific Northwest Coast.