The topic of species distribution modelling has been on of increasing interest in
recent years. As climate change is becoming of even more interest to researchers,
more tools are needed to better analyze and predict various climate change scenarios.
One particular area of interest is that of species distribution modeling....
International immersion experiences do not, in themselves, provide students with the opportunity to develop cultural competence. However, using an anthropological lens to educate students allows them to learn how to negotiate cultural differences by removing their own cultural filters and seeing events through the eyes of those who are culturally...
The production cross sections for a number of target fragments
formed by the reactions of 42- and 21- GeV²⁰ Ne and 28 GeV p with ¹⁸¹Ta have been measured. The target fragment radioactivities were
measured by off-line gamma-ray spectroscopy. Details of the measurement
as well as the calculation of the...
The public controversy over possible health hazards from radioactive fallout from atomic bomb testing began in 1954, shortly after a thermonuclear test by the United States spread fallout world wide. In the dissertation, I address two of the fundamental questions of the fallout controversy: Was there a threshold of radiation...
Sulfoxide-ligand exchange (SLE) and asymmetric halogen-metal exchange (AHME) processes were separately examined for the enantioselective synthesis of functionalized alpha-haloalkylmetal (carbenoid) reagents. Carbenoids derived from SLE were used to effect stereospecific reagent-controlled homologation (StReCH) of boronic esters and those generated via AHME were engaged in Darzens-type chemistry with aldehydes.
Abstract for...
A cultural landscape analysis of two historic cemeteries in St. Paul, Oregon demonstrates that the residents of this early community were unknowingly using grave markers to express their worldview and the identities that they felt were most important. Because of the historical and cultural development of this community as the...
Summer mortality of farmed Pacific oysters causes financial losses for shellfish growers, and selective breeding to improve survival of offspring is a promising way to reduce losses. This dissertation has two objectives to assist the development of tools for use in selective breeding programs.
Objective 1: Identify candidate genes for...
A static-renewal, seven day test was developed and
utilized to study the effects of nutrition on the sensitivity
of Mysidopsis intii Holmquist to zinc. It was found that
juvenile growth was the most reliable and sensitive endpoint
that could also reflect the subtle effects of low zinc
concentrations and diet...
Since the discovery of molecular chirality in 1848, this notion has had a substantial impact on medicine, biology, and chemistry. Extensive effort has been directed towards the construction of chiral molecules that contain sp³ hybridized stereogenic centers. In contrast, less effort has been dedicated to molecules that are chiral by...
2 -acetylaminofluorene -induced hepatocarcinogenesis in rats
proceeds in stages of initiation and promotion, similar to experimental
systems, in mouse skin. In this study promoters of liver
tumorigenesis, phenobarbital, DDT and butylated hydroxytoluene
(BHT), were compared to non-promoters, amobarbital, diphenylhydantoin
(DPH) and benz(a)anthracene (BA), for their ability to
cause liver growth...
The fermentation of honey-based musts has been a feature of civilization for millennia. Typically comprised of 75-90% (w/w) simple (i.e. fermentable) sugars, the glucose and fructose present are readily fermented by either pitched or adventitious micro-organisms. Nevertheless, despite its venerable heritage, honey-based fermentations are prone to inconsistency, and it is...
This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions were characterized over two seasons in the autumn of 2000 and the spring of 2001-at twenty-seven wetlands located throughout the valley....
The first part of this manuscript is about the total synthesis of the Arundo donax bis(indole) natural products. The A. donax alkaloids were prepared using the first example of an ynindole Diels–Alder reaction. Each were then separated, isolated, and determined to have stable enantiomeric conformations at room temperature (Chen, J.;...
Effective treatment of larval bacterial diseases is a difficult problem when
culturing ornamental fish. Oral administration of antibiotics using existing
microparticle types is not effective due to high leakage rates; furthermore, injection of
larvae is not practical. Treatment is currently limited to use of antibiotic baths, . In this
study,...
As the volume of genetic sequence data increases due to improved sequencing techniques and increased interest, the computational tools available to analyze the data are becoming inadequate. This thesis seeks to improve a few of the computational methods available to access and analyze data in the genetic sequence databases. The...
In order to generate practical ways to easily design functional flexible lattice structures, this research seeks to find a way to predict reactive forces of compressed hyperelastic cubic lattice structures. Using 3D printed test coupons, material data was collected for use in finite element analysis. Cubic lattice structures with varying...
Western juniper (Juniperus occidentalis) cover has more than doubled within the last century and currently occupies over 9 million acres in the Intermountain West. Encroachment has altered the spatial distribution of soil nutrients and plants in these systems, forming nutrient enriched 'resource islands,' under tree canopies. The purpose of this...
Unpaved roads are a critical form of infrastructure in forested landscapes but also a potential source of fine sediment that can degrade sensitive ecosystems nearby. Improved management of aggregate road surfacing can reduce sediment generation, lengthen its useful life span, reduce maintenance costs, and more importantly, mitigate the impacts of...
Many bridges along the Gulf Coast of the United States were damaged by recent hurricanes, and many more are susceptible to similar damage. This research examines performance of common anchorage connection details for AASHTO Type III prestressed concrete girders used by some transportation agencies. Full-scale specimens were fabricated and tested...
The first part of this manuscript is about the total synthesis of the aspidosperma alkaloids leuconoxine, melodinine E and mersicarpine. Our synthetic strategy used a radical translocation-conjugate addition cascade to construct the core of the natural product. Specifically, a vinyl radical was generated from the homolysis of the C–I bond...
Marine organisms produce a variety of secondary metabolites for defense, communication, and reproduction. While these uses are essential for the organisms' survival, marine natural products have demonstrated their value to human society as well. Asian countries used algae for centuries to treat or prevent illnesses as wide-ranging as cough, gout,...
We map the regional physiography and surficial lithology (Surficial Geologic Habitat or
SGH) over the continental margin of Oregon. This thesis develops, describes, and
implements an iterative interpretive method to map seafloor habitat types from disparate
geological and geophysical datasets including: bathymetric images, sidescan sonar
images, seismic reflection profiles, sediment...
Full Text:
AN ABSTRACT OF THE THESIS OF
Christopher G. Romsos for the
Organic compounds which contain one or more nitrogen atoms are especially important as they are disproportionately represented among biologically active molecules. As a result, significant effort has been focused on the development of methods for the synthesis of nitrogenous molecules. We identified the aminal as an under-explored functional group. Despite...
Aminal radical intermediates were generated by the method of radical translocation and reacted in C-C bond forming reactions with electronically deficient alkenes (Schiedler et al. Org. Lett. 2012, 14, 6092). Aminal radical intermediates can participate in inter- and intra-molecular reactions using both Bu3SnH and (TMS)₃SiH as hydride donors. Carbon–carbon bonds...
G.K. Chesterton once stated, “I am concerned with a certain way of looking at life, which was created in me by the fairytales, but has since been meekly ratified by the mere facts….The only words that ever satisfied me as describing Nature are the terms used in the fairy book,...
The bimolecular reaction of two carbenoid species resulting in the formation of a carbon-carbon double bond (pi-system), referred to herein as carbenoid eliminative cross-coupling (CEXC), involves a series of three fundamental steps: (i) ate-complex formation (transmetalation), (ii) 1,2-metalate rearrangement, and (iii) beta-elimination. All three steps are stereospecific and so the...
We took the back-propagation algorithms of Werbos for recurrent and feed-forward neural networks and implemented them on machines with graphics processing units (GPU). The parallelism of these units gave our implementations a 10 to 100 fold increase in speed. For nets with less than 20 neurons the machine performed faster...
From 1925 to 1930, Ernest H. Wiegand, a professor of Horticultural Products at Oregon State Agricultural College, developed an improved brining process for cherries. Brined cherries are used in the production of maraschino and glacé cherries, which already had a sizable market in the United States by the 1920s. This...
During the years between 1930 and 1950 a number of attempts
were made to introduce techniques and ideas from cytology,
ecology, and genetics into the field of taxonomy. Advocates of
this "experimental taxonomy" believed that cytological, ecological,
and genetic techniques would provide a rigorous, objective
methodology to replace the traditional...
Dearomatization reactions exist broadly in biosynthesis and chemical synthesis. The highly functionalized atoms of arenes can be masked by it aromaticity, and upon dearomatization, those reactive atoms can be readily applied to bond formation and further manipulation. The total synthesis of (–)-cephalotaxine and (–)- homoharringtonine is described via an oxidative...
Substituted phenols are important substructures for pharmaceuticals, agrochemicals, natural products and biological probe molecules. The properties of phenolic molecules are substantially influenced by the substitution patterns of the phenolic ring. The chemical synthesis of phenols with various substitution patterns is an enduring challenge and multiple strategies have emerged. However, some...
Reducing future fire severity is a proposed ecological benefit of salvage logging following wildfire disturbance. Considerable debate continues over the ability of such management practices to achieve this objective given limited understanding of coarse woody detritus (CWD) dynamics, fuel bed alterations, and post-fire vegetative growth. The objective of this study...
Compact storage systems demonstrating increased hydrogen storage capacity are the key to advancing the growth of the hydrogen economy throughout the world and reducing the global dependence on fossil fuels for transportation. The use of highly porous adsorbent materials for reversible hydrogen storage is a promising pathway towards achieving storage...
Traditional approaches for the direct preparation of alkenes are unable to fully control either the stereochemical configuration of the carbon-carbon double bond or else the regiochemistry of the substituents surrounding it. The recently introduced concept of carbenoid eliminative cross-coupling (CEXC) offers a remedy to these deficiencies by providing for a...
The characteristics of an inhibitor of infectious pancreatic necrosis virus (IPNV)
found in normal rainbow trout serum (RTS) were studied. The serum inhibitor had a
molecular weight of approximately 150 kDa and was dependent on divalent cations,
either Ca²⁺ or Mg²⁺. It was stable at temperatures up to 50°C and...
Pharmaceuticals, molecular catalysts, and secondary metabolites often contain nitrogen. The problems faced synthesizing compounds which contain nitrogen was because of the Lewis base reactivity of nitrogen lone pairs, and the acidic protons of some nitrogenous functional groups. We developed two methods for the synthesis of nitrogeous compounds. Additionally, we successfully...
One of the surprising things about the 2016 presidential election was how much each presidential candidate was disliked. In this historic election, questions about whether voters made their decisions by supporting their candidate or voting against another have arisen. Studies have been done in the past that examine which traits...
Kombucha is a traditional fermented beverage that has become increasingly popular in the United States due to its perceived health benefits and unique flavor profiles. The drivers of kombucha flavor have not been fully characterized, at least in part because it is produced using a complex microbial community, leading to...
Fungicide resistance has become an increasing problem in North American populations of Zymoseptoria tritici, the causal agent of septoria leaf blotch of wheat. The goal of this experiment was to determine whether Z. tritici’s resistance to one azole fungicide would predict resistance in other fungicides within the same family. Cross-resistance...
With trust in the media reaching an all-time low among Americans, I wanted to explore what prompted this shift in attitude. This thesis analyzes how Americans’ perspectives on the credibility of modern-day media and the value they place on the freedom of the press are heavily influenced by their preferred...
People like going on trips with friends and tend to plan their trips well in advance to have the best possible experience of a destination and get the most out of the places they visit and/or the activities they plan to partake in. Right now, the Internet provides a wealth...
Wheat stripe rust (WSR), also called yellow rust of wheat (Tricitum spp.), causal agent Puccinia striiformis f.sp. tritici (Pst), is a foliar disease of major economic importance on wheat, especially grown in temperate locations. WSR causes major losses of wheat yield, estimated at nearly $ 1 billion per year, and...
The COVID-19 pandemic became the deadliest epidemic since the Influenza pandemic in the early 1900s. (Centers for Disease Control and Prevention, 2023). Every government level across the United States had differing responses to COVID-19, and politicians have been the center of attention for their role in COVID policy support or...
Aaron Copland is known by many as the founder of American Music and is still considered one of the pre-eminent composers to come from the Americas, particularly North America. He composed from 1917-1973, with many of his most recognizable works composed in the early 1940s. Duo for Flute and Piano...
Here presented is a photographic catalogue, a key, and literature review for the 35 genera and 90 species of lepturine longhorn beetles (Cerambycidae: Lepturinae) found in the Pacific Northwest. Several nomenclatural changes, recognized by the global taxonomic community, but previously unknown to North American authors, are adopted, and one new...
Predators are fundamentally important for regulating and driving prey population dynamics as well as structuring ecological communities. Over-exploitation of marine resources has caused dramatic depletions of predatory fish species and shifts in marine community composition, with attendant declines in productivity and diversity of marine ecosystems. Despite the important ramifications of...
Marine bivalves are globally recognized as ecologically and commercially valuable species and, for over a century, researchers have been studying their feeding, digestion and other related physiological processes. These studies have shown that marine bivalves have complex feeding and particle processing behaviors to maximize growth in dynamic environmental conditions. Additionally,...
Complex organic transformations, such as the addition of pyrrole to ketene using planar chiral organocatalyst (*PPY), the four-component anhydride- Manniach reactions, and the site-selective desymmetrization of meso-1,2-diol, are remarkable synthetic reactions that provide high yield and high selectivity. However, the exact mechanism and origins of stereocontrol for theses synthetic organic...