The most frequent cause of pseudomembranous colitis is Clostridium difficile (C. difficile) infection. This type of colitis is characterized by an endoscopic pattern of numerous small, yellowish or whitish plaques diffusely distributed, which typically compromises the rectum extending to proximal colon. Occasionally, the pseudomembranes compromise only the transverse or right...
The increased severity of Clostridium difficile infection is primarily attributed to the appearance of an epidemic strain characterized as PCR ribotype 027. The only report that identified epidemic C. difficile ribotype 027 in an American country outside of North America comes from Costa Rica, raising the possibility that strains 027...
Clostridium difficile is an important nosocomial pathogen that has become a major cause of antibiotic-associated diarrhea.
There is a general consensus that C. difficile spores play an important role in C. difficile pathogenesis, contributing to infection,
persistence, and transmission. Evidence has demonstrated that C. difficile spores have an outermost layer,...
This thesis presents the results of quantum-mechanical first principles calculations
of optical, electronic and mechanical properties of organic molecules and solids, which have
diverse potential applications such as photovoltaics, flexible electronics, and mechanical
catalysts with applications in force sensors and self-healing materials.
The electronic and optoelectronic properties of organic thin...
Multipurpose management of hydrosystems face a number of uncertainties related to hydrologic variability and nonstationarity. Anticipated air temperature increases in the Pacific Northwest region are projected to alter the timing and quantity of streamflow associated with precipitation shifting from snow to rain, including shorter winter runoff periods, earlier spring runoff,...
Suicide is a leading cause of death amongst adolescents, and transgender and gender diverse youth are at especially high risk for suicidal ideation and attempt compared with cisgender peers. Using established ideation-to-action models of suicide and the Minority Stress Model, this project used the 2019 results of the Oregon Healthy...
This study quantifies the short-term effects of low-, moderate-, and high-severity fire on carbon pools and fluxes in the Eastern Cascades of Oregon. We surveyed 64 forest stands across four fires that burned 41,000 ha (35%) of the Metolius Watershed in 2002 and 2003, stratifying the landscape by burn severity...
Three-dimensional chemical imaging of Fe–Cr alloys showing Fe-rich (α)/Cr-rich (α') phase separation is reported using atom probe tomography techniques. The extent of phase separation, i.e., amplitude and wavelength, has been quantitatively assessed using the Langer-Bar-on-Miller, proximity histogram, and autocorrelation function methods for two separate Fe–Cr alloys, designated 2101 and 2205....
Geospatial data analysis is a multifaceted discipline encompassing the collection, processing, and visualization of diverse datasets. It models and delineates the interactions of people, objects, and phenomena within geographical spaces and predicts patterns based on the relationships between different locations. Despite significant advancements in geospatial data engineering and analytics over...
Chilodontidae is a small family of eight described characiform species popularly
known as headstanders. These small to moderately sized fishes are well known to
aquarists, who prize their striking spotted pigmentation and unusual behaviors, and to
systematists, who have revised both chilodontid genera in recent memory and studied
their phylogenetic...
SAR11 Alphaproteobacteria are the most abundant aerobic chemoheterotrophs in ocean surface waters. Previous studies have indicated SAR11 cells play an important role in marine carbon cycling and consume up to half of some common dissolved organic compounds, such as amino acids. During sequencing of the first SAR11 genome, genes for...
Student engagement with faculty is positively associated with increases in the retention and graduation rates of students enrolled in institutions of higher education. Although a considerable amount of research has focused on understanding the engagement experiences of students enrolled at four-year colleges and universities, little emphasis has been placed on...
The research was conducted in the Fundo Almendra, property of the National University of the Peruvian Amazon (UNAP). The objective was to analyze the gross forest loss in the period 2001-2021 in Fundo Almendra, the relationship between forest loss and local surface temperature, and the role of local communities’ demographics...
How does transboundary water cooperation begin at the initial stages? Countries in many transboundary basins either do not cooperate at all or have ceased cooperation altogether. Yet cooperation does often prevail, resulting in 688 water-related treaties signed between 1820 and 2007. The question we address here is, by which practices...
Full Text:
time in helping me during the beginning stages
of writing my proposal.
Thanks to Jonathan Lautze
In Part I, (4S,5R)-4,5-dimethyl-4-phenylcyclohex-2-enone (19a) was prepared in 73% yield with high enantio- and diastereo-selectivity (er > 98:2, dr > 20:1) on a multigram scale by a Yamada-Otani condensation between (E)-pent-3-en-2-one and 2-phenylpropanal catalyzed by a sulfonimide derivative of (S)-proline (18, HuaCat®). Synthetically useful transformations of the cyclohexenone product 19a...
Characiform fishes form one of the most diverse freshwater fish clades in the world. Comprising more than 2000 species and distributed primarily in South America and Africa, characiforms vary dramatically in their ecomorphology. However, the evolutionary processes responsible for the immense ecomorphological diversity remains unknown. Recently, a study postulated that...
With the increasing international focus on transboundary cooperation as a part of the Sustainable Development Goal (SDG) Framework, there is global recognition of transboundary water cooperation as a tool for improved governance and management of transboundary surface and groundwaters. Yet, there is not an agreed upon definition of transboundary water...
Nucleic acid therapeutics has cemented itself as one of the most efficacious and robust avenues for treatment of a wide range of diseases from vaccine development to treatment of liver, retina, cancer applications. Non-viral mediated gene delivery using lipid-based nanoparticle (LNP) carriers has proven its compatibility with addressing unexpected, fast...
Time-dependent electronic transport is increasingly important to the state-of-the-art device design and fabrication. The development of nanoscale sensing, the harnessing and control of structural fluctuations, and the advancement of next-generation materials all require a treatment of quantum dynamics beyond the level of traditional methods and a more nuanced approach to...
Cell signaling under external stimulation is a critical mechanism that governs many biological processes such as cell proliferation, cell migration, and cell apoptosis, etc. For multicellular organisms, the ability to synchronize heterogeneous individual cellular responses through intercellular communication is crucial to maintain normal functionality. However, even though the biological pathways...
Animals aggregate and interact in nonuniform and nonrandom patterns, which lead to group level characteristics that have important evolutionary and ecological consequences. Network analysis provides a useful conceptual framework for linking animal interactions at all scales from dyads to communities, to populations and ecosystems. Despite exciting theoretical and applied advances...
The overall focus of this thesis is on the distribution of specific lipids and membrane proteins of the external and internal membranes of plant cells, in the context of the roles that those lipids and proteins may play in microbe-plant interactions. The work includes the development of several new tools,...
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...
For the first time in several years, the El Niño-Southern
Oscillation did not dominate regional climate conditions
around the globe. A weak La Niña dissipated to ENSOneutral
conditions by spring, and while El Niño appeared
to be emerging during summer, this phase never fully
developed as sea surface temperatures in...
Climate Change in the Northwest: Implications for Our Landscapes, Waters, and Communities is a report aimed at assessing the state of knowledge about key climate impacts and consequences to various sectors and communities in the Northwest United States. This report draws on two recent state climate assessments in Washington in...
The Forest Service and the Bureau of Land Management propose to adopt coordinated ecosystem management direction for the lands they administer within the range of the northern spotted owl. This Supplemental Environmental Impact Statement (SETS) presents as alternatives the options, with slight modifications, developed by the Forest Ecosystem Management Assessment...
The group of scientists that make up the Intergovernmental Panel on Climate Change found in 2007 that the warming of Earth’s climate is unequivocal and largely due to human activity. Earth’s climate has changed in the past, though the recent magnitude and pace of changes are unprecedented in human existence....