A combination of theoretical perspectives is used to create a rich description of student reasoning when facing a highly-geometric electricity and magnetism problem in an upper-division active-engagement physics classroom at Oregon State University. Geometric reasoning as students encounter problem situations ranging from familiar to novel is described using van Zee...
Lycopodium alkaloids have shown widespread and noteworthy biological activity, consisting of over 250 known natural products. Moreover, their structural complexity and diversity have attracted considerable attention from numerous laboratories including our own. Recently, we have developed a unified approach that would provides access to numerous, previously unprepared C₁₀-functionalized lycopodium alkaloids....
Fluorescence has proven to be a robust and powerful method of analysis in numerous fields: forensics, pharmaceutics, geology, food science, and environmental sciences have all developed a large collection of fluorescence instruments and methods to overcome application-specific challenges. Biological applications saw the same development of a fluorescence toolkit with methods...
Inorganic structures play an important role in materials due to their versatility and diversity. A complete understanding of the structure of a material is vital to enhance the creation of new materials that fill voids in research. The rational design of these compounds is driven by the exploitation of structure-property...
Cognitive impairment can severely impact quality of life, and can place added strain on family and caregivers.¹⁻³ Moreover, cognitive decline has been shown to proceed to more serious conditions including Alzheimer’s disease and dementia,⁴⁻⁶ making it critical to intervene on risk factors. In addition to traditional risk factors for cognitive...
Wood-staining fungal pigments have potential uses as colorants for wood and textiles. Traditionally, organic solvents have been used as carriers for these pigments. However, other environmentally-friendly and more readily available carriers must be found. Natural oils have the potential to carry these pigments but have demonstrated color loss over relatively...
The family as a social unit is the earliest and most fundamental socialization influence and is an important contributor to children's development. Studies of family communication patterns (FCP) have emphasized two particular dimensions--a family's conversation orientation and their conformity orientation. However, many studies of FCP and its related outcomes have...
In this study, we contrasted socioemotional selectivity theory (SST;
Carstensen, 2006) with dynamic integration theory (DIT; Labouvie-Vief, 2003) using
trajectories of quantitative and qualitative social support in later life. SST is a lifespan
theory of motivational development (Carstensen, Isaacowitz, & Charles, 1999). There
is a normative decline in social support...
Biological plant invasions are diminishing the ecological integrity and function of ecosystems worldwide. A primary example of this is in the Great Basin of the United States, where invasive annual grasses, like cheatgrass (Bromus tectorum L.) and medusahead (Taeniatherum caput-medusae L. Nevski), are dominating many sagebrush-steppe ecosystems. In these invaded...
Polycyclic aromatic hydrocarbons (PAHs) are among the most widely known and studied environmental contaminants, originating from a range of natural and anthropogenic sources. PAHs are known to occur in the environment as complex mixtures, containing both unsubstituted PAHs, as well as a range of PAH derivatives. Among the less-studied of...
This dissertation is separated into two parts according to the two major distinct research projects. In Part I, the full account of synthetic studies toward C10-functionalized lycopodium alkaloids is described. In Part II, the detailed discussion on the exploration of the Pummerer cyclization methodology and its application to the total...
Robotic limbs have been shown to enable mobility in unstructured, real-world terrain; they allow robots to step around cluttered environments, scramble up hills, carry heavy loads, and even perform acrobatics. However, mechanical limbs cannot operate as a means for such dynamic locomotion if they are simply treated as general articulated...
Tree-like patterns are ubiquitous in nature. Botanical trees, river networks, and blood systems are the most well-known examples of complex hierarchical systems met in observations. Interestingly, many of such systems exhibit statistical self-similarity. There are two main types of self-similarity: Horton self-similarity and Tokunaga self-similarity. Although there is an increased...
Host-parasite interactions between the pathogen, Sphaerulina musiva, and its host, Populus spp., were examined in a series of studies. In the first study, variation in resistance of Populus nigra from 7 locations in Europe was differentiated based on the parameters cankers per cm and disease severity score. The analysis evaluated...
Cognitive self-regulation and the behavioral manifestations of cognitive self-regulation are important aspects of school readiness, yet less is known about the variation in measurement modalities within children. In this dissertation, two studies examined the makeup, antecedents, and consequents of constellations of cognitive self-regulation (CSR) measures around the transition to formal...
The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus), is established in coastal forests of the western United States. Since the discovery of SOD in the Douglas-fir / tanoak forests of...
Empirical studies and theory have identified many early predictors of children's academic achievement and externalizing problems. Moreover, research shows that children's early cognitive abilities and behavioral problems are strong predictors of later academic achievement and externalizing problems. The current dissertation studies extend previous work and unpack how early predictors relate...
Red raspberry, Rubus idaeus L., is a valuable crop for the U.S. Pacific Northwest and clonal propagation is required to produce disease-free plants and for germplasm preservation. One challenge of red raspberry micropropagation is the wide variation in growth response among the cultivars. The studies described in this dissertation were...
This thesis describes the development of a new enantioselective synthetic method employing chiral cis-2,5-diaminobicyclo[2.2.2]octane-based organometallic catalysts. The significance of this new method to organic synthesis is illustrated with preparation of enantioenriched products that are transformed to important pharmaceutical agents. Chapter 1 provides a brief historical overview of asymmetric catalysis, especially...
A three-part study was conducted into the impact of physiological and ecological variables on the net isotopic fractionation of hydrogen, α[subscript K₃₇], expressed in C₃₇ alkenones. First, alkenone-producer production, abundance, and export were characterized in the summertime Gulf of California and Eastern Tropical North Pacific using compound-specific, labeled in situ...