Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 25 of 25

Full-Text Articles in Entire DC Network

Understanding The Importance Of Intermittently Fragmented Stream Habitat For Isolated Westslope Cutthroat Trout (Oncorhynchus Clarki Lewisi) In The Colville National Forest, Washington, Forrest Michael Carpenter Dec 2016

Understanding The Importance Of Intermittently Fragmented Stream Habitat For Isolated Westslope Cutthroat Trout (Oncorhynchus Clarki Lewisi) In The Colville National Forest, Washington, Forrest Michael Carpenter

Dissertations and Theses

Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern Washington where this study was conducted. Many native salmonid populations have declined in abundance since the early 1900s due to a variety of climate- and human-driven forces. Westslope Cutthroat Trout are especially sensitive to habitat loss or degradation and to climate change. Together, climate change, habitat degradation, and non-native salmonid invasions are contributing to increasingly fragmented WCT populations. Ongoing and predicted future warming trends are expected to further fragment these populations and …


Surviving Catastrophe: Resource Allocation And Plant Interactions Among The Mosses Of Mount St. Helens Volcano, Trevor David Williams Dec 2016

Surviving Catastrophe: Resource Allocation And Plant Interactions Among The Mosses Of Mount St. Helens Volcano, Trevor David Williams

Dissertations and Theses

Mosses are some of the first colonizers to disturbed sites, yet their roles in early plant community structuring are not well understood. The primary succession zones of volcanoes provide opportunities to conduct natural experiments into how mosses contribute to early plant community formation, as well as how the unique environments found in such zones affect plant traits, particularly those associated with stress tolerance. Though plant community changes have been well-documented since Mount St. Helens (MSH) volcano erupted in 1980, the volcano's moss assemblages, their influence on other plants, and their potential roles in chemical-mediated competition and biogeochemical cycling have garnered …


Effects Of Antibiotic Mixtures Across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations, Jaclyn Rebecca Teixeira Nov 2016

Effects Of Antibiotic Mixtures Across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations, Jaclyn Rebecca Teixeira

Dissertations and Theses

Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible …


Systems Thinking In The Forest Service: A Framework To Guide Practical Application For Social-Ecological Management In The Enterprise Program, Megan Kathleen Kmon Oct 2016

Systems Thinking In The Forest Service: A Framework To Guide Practical Application For Social-Ecological Management In The Enterprise Program, Megan Kathleen Kmon

Dissertations and Theses

The U.S. Forest Service (USFS) Enterprise Program (EP), which provides fee-for-service consulting services to the USFS, is interested in integrating systems thinking into its service offerings. Despite there being several excellent sources on the range and diversity of systems thinking, no single framework exists that thoroughly yet concisely outlines what systems thinking is along with its deep history, theoretical tenets, and soft and hard approaches. This thesis is an attempt to create such a framework, aimed specifically at practical application in a land management agency, through literature synthesis injected with original analysis. The usefulness of the framework is then tested …


The Village Market: New Columbia Goes Shopping For Food Justice, Jane Therese Waddell Oct 2016

The Village Market: New Columbia Goes Shopping For Food Justice, Jane Therese Waddell

Dissertations and Theses

The Village Market is a nonprofit Healthy Corner Store that has been open since May of 2011 in the mixed-use, mixed-income New Columbia housing development in Portland, Oregon's Portsmouth neighborhood. The venture began as a "community-led" effort in partnership with Janus Youth Programs and Home Forward. The project was conceived after a private enterprise in the small grocery space designed into the development failed, leaving the neighborhood without easy access to healthy foods. This dissertation is a case study of the development process, the operation of the market, and the degree to which it addresses food justice and health equity …


Insulin-Like Growth Factor Pathway Described In Austrofundulus Limnaeus Diapause And Escape Embryos, Steven Cody Woll Aug 2016

Insulin-Like Growth Factor Pathway Described In Austrofundulus Limnaeus Diapause And Escape Embryos, Steven Cody Woll

Dissertations and Theses

Development in the annual killifish Austrofundulus limnaeus can follow two distinct developmental trajectories. Typical development includes the entrance of embryos into a state of metabolic and developmental arrest termed diapause. Alternately, embryos can escape diapause and develop directly without pause. These two trajectories are characterized by differences in the rate and timing of developmental, morphological, and physiological traits. Insulin and Insulin-like growth factor (IGF) signaling (IIS) is known to regulate entrance into diapause in a variety of invertebrates. In this thesis I explore the possible role of IGFs in the regulation of development and diapause in embryos of A. limnaeus …


A Landscape Approach To Determining And Predicting Juvenile Coho Salmon (Oncorhynchus Kisutch) Movement Timing And Growth Patterns Prior To Ocean Entry, Amelia Lee Johnson Aug 2016

A Landscape Approach To Determining And Predicting Juvenile Coho Salmon (Oncorhynchus Kisutch) Movement Timing And Growth Patterns Prior To Ocean Entry, Amelia Lee Johnson

Dissertations and Theses

Coho salmon (Oncorhynchus kisutch) rely on unique habitats during the winter season, which may dictate how much individuals may grow and when migration from freshwater rearing habitat to the ocean occurs. Here I analyze movement timing and growth patterns for coho salmon through a field-based study and a literature review. For the field portion, I examined hatchery-stocked juvenile coho salmon across four stream basins in the Russian River watershed, California to determine the relative importance of climate, landscape, and fish size metrics in predicting movement and growth patterns over a winter rearing and spring smolt outmigration time period …


Improving The Roadside Environment Through Integrating Air Quality And Traffic-Related Data, Christine M. Kendrick Aug 2016

Improving The Roadside Environment Through Integrating Air Quality And Traffic-Related Data, Christine M. Kendrick

Dissertations and Theses

Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes, congestion, and a wide mix of road users and land uses at the road edge, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. Applying transportation management strategies to reduce emissions along arterial corridors could be enhanced if the ability to quantify and evaluate such actions was improved. However, arterial roadsides are under-sampled in terms of air pollution measurements in the United States and using observational data to assess such effects has many challenges such as …


Do Forest Commons Contribute To International Environmental Initiatives? A Socio-Ecological Analysis Of Nepalese Forest Commons In View Of Redd+, Harisharan Luintel Jul 2016

Do Forest Commons Contribute To International Environmental Initiatives? A Socio-Ecological Analysis Of Nepalese Forest Commons In View Of Redd+, Harisharan Luintel

Dissertations and Theses

Forests in developing countries have the potential to contribute to global efforts to mitigate climate change, promote biodiversity and support the livelihoods of rural, local people. Approximately one-fourth of such forests are under the control of local communities, which primarily manage forests for subsistence and to meet their livelihood needs. The trend of bottom-up community control is increasing through the adoption of decentralization reforms over the last 40 years. In contrast, the United Nations has introduced the top-down program, Reducing Emissions from Deforestation and Forest Degradation (REDD+) for the conservation and enhancement of forest carbon and the sustainable management of …


Biofouling Management In The Pacific Northwest And Predation On Native Versus Non-Native Ascidians, Erin Suzanne Kincaid Jul 2016

Biofouling Management In The Pacific Northwest And Predation On Native Versus Non-Native Ascidians, Erin Suzanne Kincaid

Dissertations and Theses

Marine non-native species threaten economic and environmental health, making it crucial to understand factors that make them successful. Research on these species, therefore, allows for greater preparedness and informed management of biological invasions and increases understanding of elements structuring biological communities. Among the marine non-native species, and particularly the fouling community, non-native ascidians are a taxon of particular concern because they can crowd out native benthic species and smother mariculture products. This thesis addresses management for ascidians and other fouling organisms and includes research on the invasiveness of this taxon in addition to the invasibility of recipient fouling communities. On …


Investigating The Origin And Functions Of A Novel Small Rna In Escherichia Coli, Fenil Rashmin Kacharia Jun 2016

Investigating The Origin And Functions Of A Novel Small Rna In Escherichia Coli, Fenil Rashmin Kacharia

Dissertations and Theses

Non-coding small RNAs (sRNAs) regulate various cellular processes in bacteria. They bind to a chaperone protein Hfq for stability and regulate gene expression by base-pairing with target mRNAs. Although the importance of sRNAs in bacteria has been well established, the mode of origination of novel sRNA genes is still elusive, mainly because the rapid rate of evolution of sRNAs obscures their original sources. To overcome this impediment, we identified a recently formed sRNA (EcsR2) in E. coli, and show that it evolved from a degraded bacteriophage gene. Our analyses also revealed that young sRNAs such as EcsR2 are expressed …


The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard Jun 2016

The Terroir Of Pinot Noir Wine In The Willamette Valley, Oregon : A Broad Analysis Of Vineyard Soils, Grape Juice And Wine Chemistry, Kathryn Nora Barnard

Dissertations and Theses

Terroir is determined by a combination of factors in the vineyard including the grape varietal, geology and soil, soil hydrology, physiography, and climate. Although most studies have examined regional differences in wine flavors and associated provenance of wine based on chemistry, few have examined the chemistry of the soil and the ability to trace that chemistry to grape juice and, finally, to the wine. This dissertation examines what soil physical and chemical differences specific to this region might influence grape juice chemistry and wine chemistry.

Wine-grapes in the Willamette Valley, Oregon, are grown on three major soil parent materials: volcanic, …


Stranding Mortality Patterns In California Sea Lions And Steller Sea Lions In Oregon And Southern Washington, 2006 To 2014, Kessina Lee Jun 2016

Stranding Mortality Patterns In California Sea Lions And Steller Sea Lions In Oregon And Southern Washington, 2006 To 2014, Kessina Lee

Dissertations and Theses

As changing ocean conditions lead to declining fish stocks and movement of forage fish, sea lions on the Oregon coast are subject to the pressures of declining prey availability and increasing conflicts with commercial and recreational fisheries. An analysis of strandings of California sea lions, Zalophus californianus, and Steller sea lions, Eumetopias jubatus, from 2006 to 2014, included cause of death, changing ocean conditions, and anthropogenic activity. Causes of death included disease, injury, and human interaction, such as gunshot wounds, fisheries net entanglements and boat strikes.

Oregon and Washington strandings of California sea lions are primarily adult and …


Green Roofs And Urban Biodiversity: Their Role As Invertebrate Habitat And The Effect Of Design On Beetle Community, Sydney Marie Gonsalves May 2016

Green Roofs And Urban Biodiversity: Their Role As Invertebrate Habitat And The Effect Of Design On Beetle Community, Sydney Marie Gonsalves

Dissertations and Theses

With over half the world's population now living in cities, urban areas represent one of earth's few ecosystems that are increasing in extent, and are sites of altered biogeochemical cycles, habitat fragmentation, and changes in biodiversity. However, urban green spaces, including green roofs, can also provide important pools of biodiversity and contribute to regional gamma diversity, while novel species assemblages can enhance some ecosystem services. Green roofs may also mitigate species loss in urban areas and have been shown to support a surprising diversity of invertebrates, including rare and endangered species. In the first part of this study I reviewed …


Investigating The Effects Of 17Α-Ethynylestradiol On Mitochondrial Genome Stability, Alicia M. Chivers May 2016

Investigating The Effects Of 17Α-Ethynylestradiol On Mitochondrial Genome Stability, Alicia M. Chivers

Dissertations and Theses

Environmental toxicants are ubiquitous throughout the environment as a result of human activity. Among these toxicants, environmental estrogens are a category of particular concern due to their environmental prevalence and potency in altering reproductive traits. While many studies have addressed the detrimental effects of environmental estrogens on both aquatic and terrestrial organisms, few have analyzed the potential for these compounds to alter mitochondrial function. Mitochondria are the primary energy-generating system for all eukaryotic life, supporting all aspects of development, metabolism, and growth. Each cell within the body contains many mitochondria which in turn contain multiple copies of their own DNA …


The Foundations Of Network Dynamics In An Rna Recombinase System, Jessica Anne Mellor Yeates May 2016

The Foundations Of Network Dynamics In An Rna Recombinase System, Jessica Anne Mellor Yeates

Dissertations and Theses

How life originated from physical and chemical processes is one of the great questions still unanswered today. Studies towards this effort have transitioned from the notion of a single self-replicating entity to the idea that a network of interacting molecules made this initial biological leap. In order to understand the chemical kinetic and thermodynamic mechanisms that could engender pre-life type networks we present an empirical characterization of a network of RNA recombinase molecules. We begin with 1-, 2-, and 3-molecular ensembles and provide a game theoretic analysis to describe the frequency dependent dynamics of competing and cooperating RNA genotypes. This …


Information Representation And Computation Of Spike Trains In Reservoir Computing Systems With Spiking Neurons And Analog Neurons, Amin Almassian Mar 2016

Information Representation And Computation Of Spike Trains In Reservoir Computing Systems With Spiking Neurons And Analog Neurons, Amin Almassian

Dissertations and Theses

Real-time processing of space-and-time-variant signals is imperative for perception and real-world problem-solving. In the brain, spatio-temporal stimuli are converted into spike trains by sensory neurons and projected to the neurons in subcortical and cortical layers for further processing.

Reservoir Computing (RC) is a neural computation paradigm that is inspired by cortical Neural Networks (NN). It is promising for real-time, on-line computation of spatio-temporal signals. An RC system incorporates a Recurrent Neural Network (RNN) called reservoir, the state of which is changed by a trajectory of perturbations caused by a spatio-temporal input sequence. A trained, non- recurrent, linear readout-layer interprets the …


Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters Mar 2016

Pharmaceutical Contaminants As Stressors On Rocky Intertidal And Estuarine Organisms: A Case Study Of Fluoxetine, Joseph Richard Peters

Dissertations and Theses

Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects …


Phylogeography Of Two Species Of The Genus Apochthonius Chamberlin, 1929, In The Pacific Northwest (Arachnida, Pseudoscorpiones), Brandi Lynn Welch Feb 2016

Phylogeography Of Two Species Of The Genus Apochthonius Chamberlin, 1929, In The Pacific Northwest (Arachnida, Pseudoscorpiones), Brandi Lynn Welch

Dissertations and Theses

I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic …


Survivorship And Breeding Dispersal Patterns Of A Migratory, Socially Monogamous Passerine; The Scissor-Tailed Flycatcher (Tyrannus Forficatus), Adam John Becker Jan 2016

Survivorship And Breeding Dispersal Patterns Of A Migratory, Socially Monogamous Passerine; The Scissor-Tailed Flycatcher (Tyrannus Forficatus), Adam John Becker

Dissertations and Theses

Survivorship (the likelihood of survival from one year to the next) and breeding dispersal (movement between breeding seasons) exhibit considerable variability at both the inter- and intraspecific levels. Using eight years of data (2008-2015), from my study site in southwest Oklahoma, I characterized survivorship and breeding dispersal of the Scissor-tailed Flycatcher (Tyrannus forficatus) in a mixed-grass prairie ecoregion. My results suggest that estimated survivorship of Scissor-tailed Flycatchers is low, especially to the congeneric Eastern Kingbird (T. tyrannus), and was likely underestimated due to the tendency of Scissor-tailed Flycatchers to disperse long distances.


Sex-Specific Fungal Communities Of The Dioicous Moss Ceratodon Purpureus, Mehmet Ali Balkan Jan 2016

Sex-Specific Fungal Communities Of The Dioicous Moss Ceratodon Purpureus, Mehmet Ali Balkan

Dissertations and Theses

Mosses display a number of hallmark life history traits that influence their ecology at the population and community level. The long lived separation of sexes observed in the haploid gametophyte (dioicy) is one such feature of particular importance, as it is observed in the majority of bryophytes and creates intraspecific specialization of male and female individuals.

The prevalence of sexually dimorphic mosses raises the possibility of sex-specific interactions with fungi as observed in some vascular plants. Here I investigated how moss sex shapes fungal communities associated with gametophytic tissues of the ubiquitous moss, Ceratodon purpureus. Using greenhouse populations of …


Revised Distributional Estimates For The Recently Discovered Olinguito (Bassaricyon Neblina), Using Museum And Science Records, Beth E. Gerstner Jan 2016

Revised Distributional Estimates For The Recently Discovered Olinguito (Bassaricyon Neblina), Using Museum And Science Records, Beth E. Gerstner

Dissertations and Theses

In the context of global change, a necessary first step for the conservation of species is gaining a good understanding of their distributional limits. This is especially important for biodiversity hotspots with high endemism such as the Northern Andes. The olinguito (Procyonidae: Bassaricyon neblina) is a recently described, medium-sized carnivoran found in Northern Andean cloud forests. A preliminary distributional model was published along with the original description, and I here provide revised distributional estimates using updated locality records and more current ENM methods. I build ecological niche models in Maxent using occurrence data (georeferenced museum records and citizen science-derived photo-vouchers) …


Synthetic Functionalized Scaffolds For Culture And Maintenance Of Primary Human Hepatocytes, Douglas Macpherson Jan 2016

Synthetic Functionalized Scaffolds For Culture And Maintenance Of Primary Human Hepatocytes, Douglas Macpherson

Dissertations and Theses

There is deficit in the number of human livers that are available for transplantation. Additionally, there is no reliable model for the liver environment available for laboratory research. Tissue engineering provides alternatives for organ transplantation. We have created a supramolecular biomaterial out of simple peptide and saccharide building blocks to act as a hydrogel scaffold to support culture of liver cells. Using a self-­‐assembling peptide fiber decorated with functional molecules, we were able to culture primary human hepatocytes demonstrate their viability and maintenance of phenotype. The hydrogel material was formed by co-assembly in aqueous buffer and characterized using transmission electron …


"Molecular Analysis Of Virulence Factors Unique To Leptopilina Heterotoma-A Parasitic Wasp Of Drosophila Spp.", Noelle Dziedzic Jan 2016

"Molecular Analysis Of Virulence Factors Unique To Leptopilina Heterotoma-A Parasitic Wasp Of Drosophila Spp.", Noelle Dziedzic

Dissertations and Theses

Endoparasitioid wasps of Drosophila spp. frequently avoid or overcome the immune defense mechanisms of their fly hosts. Leptopilina heterotoma (Lh) is a generalist wasp species, successful on many Drosophila spp. world-wide. During oviposition, the female wasp introduces venom proteins and virus-like particles (VLPs) into developing fly larvae. VLPs are endocytosed by plasmatocytes, a macrophage-like blood cell that is the most abundant hemocyte present in the circulating hemolymph. Once internalized, VLPs destroy plasmatocytes by programmed cell death. To understand the contributions of VLP proteins in VLP trafficking within host cells, we took advantage of proteomic data from purified Lh VLPs. Two …


Expression And Function Of A Putative Cox-Like Gene In D. Melanogaster, Michelle S. Batchu Jan 2016

Expression And Function Of A Putative Cox-Like Gene In D. Melanogaster, Michelle S. Batchu

Dissertations and Theses

Cyclooxygenases (COX) are the enzymes that catalyze the conversion of arachidonic acid into prostaglandins. In mammals, isoform COX-1 is constitutively expressed, whereas the isoform COX-2 gene expression is induced, primarily at sites of inflammation. While eicosanoids play a major role in inflammation in insects, their existence in fruit flies has not been reported. Recent computational analyses by Qi and Singh (2014) have identified putative COX-like enzymes in the fruit fly Drosophila melanogaster. Here we compare the expression patterns of these enzymes and the effects of their knockdown in immune cells of D. melanogaster third instar larvae. Because of high genetic …