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Land Use Impacts on Water Quality in Oak Creek Watershed
Get PDFUnderstanding the relationships between land use, water quality, and groundwater is crucial for ecological, economic, and water management decisions. This study aims to provide a comprehensive analysis of the land use activities and hydrologic processes influencing the water quality of Oak Creek watershed. Objectives of this study were: 1) to determine land use influence on stream water anion concentration along a longitudinal gradient; 2) to assess potential effects of stream-aquifer interaction on stream water quality; and 3) to determine potential origins and seasonal variability of surface water flow. Water samples were collected between January 2018 and November 2019 from 22 stream sites and 19 shallow groundwater wells in Oak Creek watershed spanning forested, agricultural, and urban land use. All samples were analyzed for anion (i.e., chloride, sulfate, nitrate, phosphate) concentrations and stable isotopes of water. Results indicate that: 1) Oak Creek acts as an integrator of precipitation received in high elevations and incoming ground and surface water sources as it moves downstream driving overall stability of isotopic compositions but leading to increasing chloride and sulfate concentrations; 2) shallow groundwater in agricultural settings exhibits high spatial variability; and 3) land use – water quality relationship are complex and temporally variable
Adaptation to long-term osmotic stress in Saccharomyces cerevisiae
Get PDFAn important goal of evolutionary biology is to identify the genetic mechanisms underlying phenotypes in organisms. Understanding adaptation to osmotic stress has many applications, since this stress affects almost all organisms on Earth. By studying the model organism Saccharomyces cerevisiae using experimental evolution, we can learn about genetic mechanisms driving adaptation to an osmotically stressful environment. I worked with three replicate populations of a Wine/European strain of S. cerevisiae that had adapted to osmotic stress in the laboratory for 750 generations. Seven mutations were identified in these evolved populations as candidates for adaptive alleles and were the subject of my experiment. I subjected cells from the ancestral and evolved strains to evolution experiments that competed their genotypes. I hypothesized that if these mutations were indeed beneficial in an osmotic stress environment, then they would increase in frequency in these experiments. My results showed either no significant change in allelic frequencies or an increase in the ancestor allele. I conclude that while these mutations may have been beneficial in the past environment, they are not advantageous in the yeast populations I studied. This could be due to my experimental design and/or due to the complexity of osmotic stress resistance in yeast.Key Words: Experimental Evolution, Genetics, Osmotic Stress, Saccharomyces cerevisia
Comparison of complete blood count and biochemistry panels between cats with and without clinically apparent feline upper respiratory tract disease
Get PDFFeline upper respiratory tract disease (FURTD) is a complex syndrome that affects domestic cats, with clinical signs including general malaise, ocular and nasal discharge, and oral pathology. Our study compared the presence or absence of five common FURTD pathogens and routine blood parameters between 18 participating cats. Owners tended to underreport FURTD signs, particularly oral pathology. Additionally, several cats that displayed clear FURTD signs tested negative for common FURTD pathogens, while two cats that did not have any owner-reported signs tested positive. Clinically ill cats had a suggestively higher neutrophil count (n = 17, p = 0.0081) and neutrophil-lymphocyte ratio (n = 18, p = 0.048) than clinically healthy cats, although the statistical significance was eliminated after correction for multiple comparisons. Cats that tested positive for at least one respiratory pathogen had a suggestively lower platelet count (n = 13, p = 0.0615) than cats that tested negative for all pathogens. Our findings suggested a weak association between neutrophilia and FURTD, which may potentially aid in early detection of the disease, even in patients with subclinical infections. However, further research with a larger study population may enable the acquisition of more statistically significant findings
Power Generation via a Thermoelectric Generator Driven by a Reversible Exothermic Reaction
Get PDFSolar thermal energy can be stored and later converted to electrical energy using a combination of thermochemical energy storage (TCES) and a thermoelectric generator (TEG). This TEG and TCES combination illustrates a potential route for clean electricity storage from renewable energy. TCES allows for thermal energy from the sun to be stored as chemical energy that can then be utilized to generate electrical energy through a TEG device at a later time. While there are many methods of TCES, this paper presents a storage through a reusable porous matrix impregnated with CaCl2. The dehydration and hydration of CaCl2 within the matrix material provides a reversible thermochemical reaction for TCES. The dehydration of CaCl2 hexahydrate within the matrix material stores thermal energy; while, the hydration of anhydrous CaCl2 within the matrix material provides a heat input for the TEG device. The TEG principle of operation is based upon the Seebeck effect; a phenomenon that converts a temperature difference into a voltage difference to create power. Thus, the thermochemical reaction between CaCl2 and water creates a hot side for a temperature difference with the ambient cool side. In general, the Seebeck effect is inherently a weak thermoelectric effect; and it is for this reason that the TEG efficiency is very low as compared to a photovoltaic and battery storage system. Nevertheless, the TEG and TCES combination poses a cheaper and more scalable storage system that could still compete with the PV and battery storage system. In terms of cost analysis, TEGs are cheaper within low peak power but high storage capacity settings; this advantage makes the TEG and TCES combination comparable to that of the PV and battery storage system. Experimental investigation illustrated that the matrix material produced 0.6mW/g of power; this was then maintained for about 17 min before dropping to a negligible temperature difference. While this illustrates the low overall energy efficiency of a TEG and TCES storage system, the economic motivation behind this method is presented. With a long solar collection time, a high storage capacity, and a low TEG peak power, the TEG/TCES storage system could be beneficial. Within further investigations, utilizing a heat sink, exploring the cold side of the TEG, and considering a more insulated experimental set up could be beneficial for this proof of concept.Key Words: energy storage, solar thermochemical, thermoelectric generato
Equity and Gender Bias in High School Music Programming in the Pacific Northwest: A Case Study
Get PDFThe purpose of this thesis is to examine gender and historical bias in wind band music and related practices in the Pacific Northwest. This research was conducted via an IRB approved research study, Equity and Gender Bias in High School Music Programming in the Pacific Northwest: A Case Study, which interviewed a range of current band teachers in the Pacific Northwest and students studying to become music educators. Using data from the interviews in addition to my research on historical, cultural, and pedagogical practices, I seek to inform both current and future educators about the unintentional and historical, biased programming practices in wind band music. My goal is to invite further discussions about repertoire choices in wind band music and how the field can move forward towards a more equitable future.Key Words: wind band music, programming, women, feminism, diversity, secondary school, music, educatio
The Impact of Migrant Labor on Labor Productivity: Evidence from the United States and Europe
Get PDFAccording to the International Labor Organization, the use of migrant labor force has shown an increasing trend over the past decade. This indicates that migrant workers are potentially becoming a vital factor affecting the world’s economy and industries. Since labor productivity is important indicator of economic growth and prosperity, it is important to understand the contribution of foreign workers to domestic productivity. This paper studies the effect of foreign workers on labor force productivity by analyzing data on migrant labor proportions and skill levels to determine which affects labor productivity in Germany, Spain, the United Kingdom and the United States. The data are analyzed through the use of ordinary least squares regression with the goal of determining how foreign labor affects labor productivity. The result from the regression analysis concludes that the proportion of foreign workers that are more highly skilled is associated with an increase labor productivity within a country.
Key Words: Labor Productivity, migrant workers, occupations, skill levels, migration policie
The Effects of Social Media on The Human Psyche
Get PDFThis thesis is a study of the effects of social media and the influence it has over people and their wellbeing. The study within the thesis manipulates the social media habits of Oregon State students, and looks at the changes in their wellbeing. Throughout the background research the evidence supports a reasonable conclusion that social media has negative influences on individual wellbeing. The findings of the thesis research are, however, inconclusive, with data that supports the idea that social media is negative for wellbeing, and some data that contradict that idea
Ethical Research Conduct Scholarly Recommendations: Exposure Research During and After Disasters
Get PDFThe frequency of devastating disasters has increased in the United States due to the presence of climate change. Human subject research is often conducted in these post-disaster areas to gain valuable data and insights. In recent years, discourse regarding the ethical nature of research conduct in these exposure areas has become increasingly prevalent. The dominant rhetoric of ethical research conduct continues to be effective, however, lacks a comprehensive nuanced research approach in the instances of exposure science, and specifically in post-natural disaster areas. For this project, I conducted a literary review of applicable peer-reviewed published
research and data on ethical researcher conduct in natural disaster areas. Results from this review span independent research, textbook excerpts, literary reviews, and case studies. Then using an inductive thematic analysis approach, 3 main themes and 9 subthemes were identified. Main
thematic recommendations include Institutional Review Board (IRB) evolution; stakeholder collaboration; and prioritization of research subjects. Along with these overarching thematic recommendations were subthemes: to include informed consent; IRB preapproval; and vulnerability, were also identified. This study revealed that overall, the rhetoric surrounding ethical exposure research in post-disaster areas is underdeveloped and requires further delineation in many areas, specifically the concept of vulnerability.Keywords: Disaster research, literary review, ethical research, natural disaster, beneficenc
A Dive into the Pacific Fish Microbiome: Exploration of Antibiotics from a Unique Ecosystem
Get PDFWith the rise of resistant bacterial pathogens, currently prescribed antibiotics are rendered useless. In recent years, marine natural products (MNPs) have emerged as novel sources for drug leads. The ocean is a complex environment where marine animals cohabitate with many, and sometimes harmful microorganisms and viruses, but resist infections. Developed defenses, specifically mucous on fish scales, has been found to contain a variety of immunological chemical defenses and host a diverse microbial community. Recently, cultures from the exterior fish microbiome has been found to inhibit growth of human and fish pathogenic bacteria and fungi.
In exploration for new antibiotics, bacteria were isolated from the mucous of Pacific fishes and screened for their antibiotic-producing potential. Mucous swabs from juvenile fish yielded 47 different microbial strains. Strains were grown and extracted with organic solvent to obtain chemical extracts. Extracts were tested in antimicrobial microbroth assays against Staphylococcus aureus, Escherichia coli, and Candida albicans at 125 µg/mL. Nineteen extracts yielded potent inhibitory activity in at least one assay. In a case study of a particularly potent extract (PF-1-D), three inhibitors against methicillin resistant S. aureus and one metabolite with moderate inhibition of colon carcinoma were identified. Metabolites were isolated using multiple chromatographic techniques and elucidated by nuclear magnetic resonance and mass spectrometry. Overall, the potent anti-infective activity of these strains showcase bioactive metabolites that can be found within the Pacific fish microbiome, a potentially untapped source of novel antibiotics.
Keywords: marine natural products, fish mucous, antibiotics, Pseudomonas sp., antimicrobial resistanc
Exploring the Relationship Between Sleep and Self-Regulation in Kindergarteners
Get PDFSelf-regulation is the ability to regulate cognitions, emotions and behaviors and is important for success in school and adaptation in children. The amount and quality of sleep a child receives can influence their development and self-regulation. This study examines the relationship between children’s self-regulation in the fall of their kindergarten year and sleep variables. Specifically, this study aims to see if the amount of sleep a child gets each night, the number of times a child wakes up at night, or the amount of time it takes for a child to fall asleep each night predicts self-regulation at the beginning of kindergarten. A total of 246 participants were included as a part of a larger study conducted at Oregon State University. Three self-regulation measures were used to measure self-regulation skills in children: Head-Toes-Knees-Shoulders-Revised (HTKS-R), Dimensional Card Change Sort (DCCS), and Day/Night Stroop Test. Results from the study indicated the amount of time a child took to fall asleep predicted self-regulation skills when measured by the Day/Night Stroop Test. Lower Day/Night Stroop Test scores were associated with increased length of time it takes for a child to fall asleep at night. Additionally, a trend-level significance showed an association between children who take longer to fall asleep at night and lower scores on the HTKS-R. Findings from this study can be used to educate parents, teachers, and practitioners on the importance of sleep on children’s self-regulation and development, hopefully helping to prioritizing children’s health and well-being more in the future.Keywords: self-regulation, executive function, cognition, sleep, sleep qualit