Biology Commons^™

Targeting The Maladaptive Effects Of Binge Drinking On Circadian Gene Expression, Courtney Ledford

University Honors Theses

Previous studies 1) support a role of circadian genes in regulating alcohol intake, and 2) reveal that harmful alcohol use alters circadian rhythms. However, there [is] minimal knowledge of the effects of chronic alcohol processes on rhythmic circadian gene expression across brain regions important for circadian biology and alcohol intake. Therefore, the present study sought to test the effects of chronic binge-like drinking on diurnal circadian gene rhythms in the master circadian pacemaker (SCN), the ventral tegmental area (VTA), and the nucleus accumbens (NAc) in High Drinking in the Dark-1 (HDID-1) mice, a unique genetic risk model for drinking to …

Orthotrichum Lyellii As An Active Moss Biomonitor: Examining The Interplay Between Ambient Pm10, Bulk Deposition And Heavy Metals In An Urban Environment, Scott Bradley Kiel

Dissertations and Theses

The importance of monitoring and preventing pollution in the environment is a globally recognized issue. Of the criteria pollutants outlined by the United States Environmental Protection Agency, particulate matter is among these least understood in relation to toxicity and most wide-spread. Many governments have employed continuous air quality monitoring networks to track ambient levels of particulate matter, but are often too widespread to capture the heterogeneity of the urban environment, especially for heavy metal deposition. In Portland, OR, the epiphytic moss Orthotrichum lyellii was successfully used as a low-cost passive biomonitor to increase the spatial resolution of pollution around the …

The Relationship Between The Gut Microbiome And Sleep Examined Through Associated Human Disease, Jessica Flikkema

University Honors Theses

The crosstalk between the gut microbiome and sleep affects many aspects of human health. This paper looks at metabolic disorders affected by sleep deprivation, sleep disorders affected by the gut microbiome, and other disorders related to both systems. The possible mechanisms of disease are examined for obesity, diabetes, and irritable bowel syndrome as examples of metabolic diseases. Insomnia, narcolepsy, and obstructive sleep apnea as examples of sleep disorders. And hypertension, Alzheimer’s disease, and psychiatric diseases as examples of diseases related to both systems. Understanding of these mechanisms is then used to support probiotics, fecal microbiota transplants, and regulated sleep schedules …

Climate And Intraspecific Geographic Variation Of Nests And Eggs In The Eastern Kingbird Tyrannus Tyrannus, Samantha Marie Gillette

Dissertations and Theses

The reproductive success of birds is ultimately driven by the traits of nests, eggs, and incubation behavior and the interactions among them. Avian reproduction varies on large geographic scales, most prominently between tropic- vs. temperate-breeding species, but also on finer scales, such as along latitudinal and elevational geographic gradients. However, despite the importance of eggs and nests, how their traits vary geographically in response to differences in regional climate remains understudied.

We studied Eastern Kingbirds (Tyrannus tyrannus), which have been previously demonstrated to alter incubation length in response to local climate conditions. Our study sites, Kansas (KS), New …

In Sickness And In Health: Parasites Of Stranded Pacific Harbor Seals (Phoca Vitulina Richardii) In Northern Oregon And Southern Washington, Cecily Douglas Bronson

Dissertations and Theses

Parasites have the capability to infect virtually every living organism on the planet and have adapted to infiltrate every trophic level. Many species have complex indirect life cycles and rely upon hosts at different levels of the food web for growth and reproduction. In the marine environment, having a high level of parasite diversity is thought to indicate a more stable ecosystem than an environment with low parasite diversity. As one of the top predators in their environment and because of their amphibious behaviors, pinnipeds (seals and sea lions) are exposed to a wide variety of parasites, making them ideal …

The Effect Of Media And Filtration In Inducing The Oxidative Stress Response In Escherichia Coli, Suzanne Hollingsworth

University Honors Theses

Escherichia coli grown in complex medium (LB), but not defined medium (DGC), arrest DNA replication when collected on membrane filters and resuspended in fresh media. The arrest is similar to that observed when cells are challenged with hydrogen peroxide. Yet, the reason behind this arrest is unknown.

I hypothesized that the arrest in replication in complex medium after filtering might be due to oxidative shock, and therefore cells grown in complex medium and filtered should induce an oxidative stress response similar to cells treated with hydrogen peroxide. Utilizing the indicator dye H₂DCFDA, which fluoresces in response to reactive …

Evaluation Of Postmortem Protein Expression In Determining Cause Of Death, Zoe Robinson

University Honors Theses

Cause of death differentiation during a medicolegal autopsy can be complicated by several factors, including sample conditions which can create uncertainty. Postmortem protein analysis has potential to be used as an additional evidentiary tool in determining cause of death. Proteomic biomarkers offer a method to directly measure physiological conditions at time of death that are stable in a postmortem state. Specific protein expression levels have been studied for their postmortem application in significantly differentiating many different causes of death. Work done in regard to asphyxial, toxicological, and traumatic deaths will be specifically discussed here. Proteins will be reviewed for potential …

Ours Lived Lived: Faculty Responses To Stem Students' Lived Experiences, Stan Nguyen

University Honors Theses

Science, technology, engineering and mathematics (STEM) fields have historically had low undergraduate retention rates. To aid in counteracting this, classroom exercises, or 'belonging interventions' can play a vital role in keeping new STEM students motivated through the "cultural shock" period of the college transition. However, much is still unknown about STEM instructors' perceptions on belonging interventions in STEM classrooms. Would understanding students' lives and experiences in the past and present help them make better informed decisions in their teaching practices?

To answer this question, we drew upon results from a belonging intervention conducted by the Biology Education Research (BER) group …

Embryological Development And Mortality Of Danio Rerio In Long Term Exposure To 17Α-Ethynylestradiol, Seong A. Jeon

University Honors Theses

Synthetic estrogens as well as other chemicals have become an increasing issue in the impact they have on marine species particularly those sensitive to the environment. A broadly used synthetic estrogen, 17α-ethynylestradiol, has become more widely known to become a growing problem to the ecology of marine wildlife due to increased usage and lack of removal in municipal sewage treatment facilities. This study observes the impact of low level EE2 in embryos following generational exposure. Zebrafish embryos, following three generations of exposure, were observed in rate of mortality, lethality, and hatch success. Concentrations as low as 1ng/L of EE2 has …

A Literary Examination Of The Efficacy Of Zoological Conservation In The United States Versus Foreign Efforts, Madeleine M. Lecorre

University Honors Theses

Falling into the top four threats to biodiversity, human activity is impacting species around the globe like never before. Zoological conservation of threatened species aids in the support and reestablishment of these dwindling populations. The examination of conservation work done in the U.S compared to foreign efforts provides insight into strengths, reveals weaknesses, and will help us better serve threatened species around the world. The status of conservation in the U.S. as well as foreign efforts were assessed through literary review of published reports from accredited organizations. As zoologic conservation aims to conserve threatened species, it is also important to …

Helminths Of Thomomys Species (Rodentia: Geomyidae) Of Oregon, Malorri Rene Hughes

Dissertations and Theses

Although often viewed as inconsequential, parasites have significant ecological and evolutionary importance, and studying them can generate knowledge regarding their environments and their hosts. Helminths (intestinal parasites) infecting Western pocket gophers (Thomomys species) in Oregon had been documented based only on morphology prior to this study. Basing parasite identification solely on morphology is problematic because the characteristics used to identify species can be vague or similar, leading to misidentification or obscuring the true biodiversity present. Using molecular markers to verify species present not only is more reliable but also can be informative in terms of the host-parasite association. To …

A Survey Of The Solitary Native Bees Of The Leach Botanical Garden, And Their Floral Associations, Joshua Page

Biology Undergraduate Departmental Honors Theses

Solitary native bees are known to be diverse, but are not well studied in Oregon. In order to identify the bee genera present in the Leach Botanical Garden, and their floral usage, a survey was conducted over 2020 and 2021. Biweekly sampling was used to collect bees on flowers, in order to obtain floral usage data. Bees were identified to genus with published taxonomic keys. In total, 19 genera of bees were found. Bee abundance fit a normal distribution, and peaked in July. Ceratina and Lasioglossum were a significant proportion of the population, and were present in the garden from …