Over the past few decades, the ratio of women to men in many traditionally maledominated fields has become much more equal. However, in science, technology, engineering, and math (STEM) fields the ratio has not improved at the same rate. In computer science the ratio is still very uneven. Today women...
Crystals are solid materials with periodic and symmetric molecular patterns. The structure of a crystalline solid determines its properties, making it essential to study its structures. From the principle of minimum energy, a crystal will choose a structure with the lowest free energy F = U – TS. At low...
Mixed anion compounds that form ZrCuSiAs-type crystal structures exhibit remarkable properties such as superconductivity at low temperatures,
hole conduction with optical transparency in the visible region, and exciton absorption at room temperature. In this thesis, properties of a selected group of materials out of the very large set of mixed...
The ability to focus light through strongly scattering materials is opening up exciting new avenues in many fields, such as optics, computer vision, biology, and medicine, which utilize light delivery and imaging techniques. Efficient, high resolution wavefront shaping and optimization methods are crucial to enabling this new capability.
In this...
The behavior of small atomics cluster largely depends on their geometry,
due to the high ratio of surface atoms to interior atoms. One interesting aspect
to study clusters centers around characterizing the transition behavior between
nite and bulk materials, where the ratio of surface atoms to interior atoms is
very...
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...
In the spring of 2020, the COVID-19 pandemic began. This prompted quarantines, mask mandates, and stopped many businesses and services. This study asked the question of what people decided to do in terms of their recreation habits in response to the pandemic. We took a sample of Oregon State University...
Although the human health and social benefits from outdoor recreation are numerous, there is mounting evidence that outdoor recreation can negatively impact wildlife. Shorebirds are known to be especially sensitive to recreation-related disturbance because they nest and forage directly on beaches that are often used for recreation. Many studies have...
In the last decade, many U.S. parks and protected areas (PPA) experienced record breaking visitation levels. Managers of these PPAs face the challenging task of providing a range of quality and accessible outdoor experiences without compromising the integrity and health of surrounding ecosystems. Understanding how PPA visitors move and interact...
Traditional Ecological Knowledge (TEK) is a Knowledge-belief-practice system acquired through intergenerational direct and indirect observations representing past and current understandings of environments and integrates Indigenous value systems. TEK has become a popular topic recently as Indigenous stewarded lands contain more biodiversity and are more adaptable. It is critical for Indigenous...
Ensuring sustainable development is a growing societal concern, providing rationale to examine the current role and efforts towards implementing sustainable building initiatives within the United States. Sustainable building initiatives refer to the design, operation, and maintenance of a building while considering its conservation efforts and pollution reduction performance. These initiatives...
In the United States, rates of youth vaping are alarmingly high. In 2018, the U.S Surgeon General declared youth vaping as an epidemic (Truth Initiative, 2019a). However, LGBTQ+ youth are disproportionately affected. In 2017, current e-cigarette usage in youth was 13.2% among heterosexuals, but was 17.5% in LGBTQ+ youth (CDC,...
This capstone project explores the efficacy of Geography Information Systems (GIS) to promote scientific literacy in secondary science classrooms and students’ preference of GIS when learning scientific literacy skills. For the scope of this project, secondary science classrooms are defined as grades 6-12 and scientific literacy is defined as 1)...
As indicated by the title, this thesis generalizes the Main Inertia
Theorem of Ostrowski and Schneider [8]. The first three results
concern the formation of a polynomial function f(A, A*, H) so that
the existence of an hermitian H for which f(A, A*, H) is positive
definite is a necessary...
Connecting with nature is associated with social, physical, and emotional benefits such as stress relief, improved physical health, and lower crime. Parks and other natural areas offer spaces in which to connect with nature and reap these and other benefits (e.g., family bonding, social events, learning). Despite increasing populations of...
This thesis presents the results from Monte Carlo calculations on classical vector spins in
face-centered-cubic (FCC) lattices. The goal of the study was to understand the effect of
interlayer coupling, dilution of magnetic atoms in the lattice, and symmetry-changing
strain.
Experimental work by T. M. Giebultowicz et al. and J....
Homelessness has many faces, several of which society will never truly see. The homeless population has begun to change during the recession, as families lose their homes to foreclosures due to high interest mortgages or become evicted from rental dwellings as one or both wage earners lose employment. The initial...
Despite being internationally recognized as basic human rights, water, sanitation, and hygiene (WASH) insecurity continues to exist throughout the United States, particularly among low-income and unhoused portions of the population. Previous investigations into the intersection of WASH and people experiencing homelessness (PEH) in the US have primarily taken place in...
Wilderness character monitoring (WCM) is an interagency strategy created in 2008 in collaboration between the four federal land management agencies that manage designated wilderness (Forest Service, National Park Service, Fish and Wildlife Service and Bureau of Land Management) and other contributors (Landres et al. 2008a). The reports created from this...
School-based comprehensive sex education (CSE) can reduce adolescent sexual health problems. However, only 49-55% of adolescents receive CSE that meets national standards. African American youth (AAY), particularly males, are less likely to receive CSE. AAY evidence a high prevalence of STIs/teen pregnancy. Internet-based CSE offers a supplemental option. We examined...
My work in the Harper Nanotoxicology Lab focuses on science communication. The Harper Lab conducts research to address data gaps regarding the toxicity of micro and nanoplastic in the environment, specifically in aquatic habitats. It is important for the public to understand what the lab does, and how they can...
Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions of people. They are some of the most vulnerable ecosystems in the United States and have been altered by human activities such as livestock...
Water availability is a controlling factor in stream ecosystems with direct influences on habitat and aquatic ecosystem process, but little work has been done evaluating how biota respond to natural variations in low flow conditions during summer, and which biotic or abiotic features in the system may link most closely...
A variety of stakeholders require information about marine systems. In the open ocean, pilots of marine vessels require knowledge about environmental conditions for safe passage and route planning. On the coastline, communities rely on information about nearshore dynamics to increase safety from coastal hazards such as nearshore pollutants, coastal erosion,...
In this dissertation, I examine emerging economic issues which intersect outdoor recreation, environmental quality, public land use, and public health advisories. First, I explore the potential impacts of social media on visitation to public land. Social media, and in particular Instagram, has been suggested by journalist and land managers as...
Any interaction with another person requires some judgement of their characteristics from a short amount of time. Each day a person can interact with many individuals and quick judgments have to be made in each situation to decide how to act or react. This means a person can make hundreds...
The rapid accumulation of polyethylene terephthalate (PET) plastic waste caused by disposable plastic water bottle use is a worldwide problem that will continue to affect our environment, economy and society unless new methods of reduction and degradation are explored. The large amounts of energy and resources that are required during...
The roles of today’s grandparents have drastically changed from fifty years ago. Grandparents are now expected to give up their retirement and that “grandparent relationship” to fill in the position of “parent” when the child’s parents can no longer do so. This can be a hardship for both the grandparents...
Even in remote environments, human and natural systems are connected. Pressing environmental and social changes warrant the field of science to not only continue to enhance understanding of the natural world, but also consider the socio-ecological implications of research in the coupled human-natural system. Additionally, a need exists for communication...
Inheritance from pre-existing mantle domains and fluid and melt contributions from active subduction together produce the geochemical signatures of mantle-derived arc basalts. In this context, this work evaluates the evolution of Cascadia mantle sources by documenting the isotopic and compositional characteristics of primitive basalts along a transect across the Eocene-Oligocene...
The COVID-19 pandemic impacted the international development sector through various external and internal stressors. Community engagement practices that international non-governmental organizations and non-profits conducted were disrupted by the pandemic, and communities were faced additional challenges when international development workers were required to socially distance or relocate at the onset of...
Anaerobic digestion is a microbially mediated process by which organic matter is decomposed in the absence of oxygen. The end products of anaerobic digestion include treated sludge and biogas, a mixture of methane and carbon dioxide, which can be recovered and used for energy generation. The majority of wastewater treatment...
Amendments and fertilizers applied to optimize crop production and improve soil health also supply inputs of soil organic matter (SOM) and nutrients that affect soil microorganisms. In the dairy-intensive Pacific Northwest, dairy manure is stored as slurry mixtures until conditions are appropriate for soil application. During storage, the manure begins...
Snow Peak is a voluminous shield volcano located ~50 km west of the axis of
the modern Cascade arc. A previously published K-Ar age estimate indicates that the
Snow Peak lavas are ~3 Ma. Subsequently, the preliminary research framework for
studying the Snow Peak lavas focused on constraining the petrogenesis...
Despite being a highly charismatic and frequently exhibited organism,
Giant Pacific Octopus (Enteroctopus dofleini) population dynamics
are poorly understood. Basic monitoring data for this species is
limited to bycatch and stomach contents of other fisheries species. An
essential step to a better estimation of population size and
productivity is to...
Previous research has shown significant improvements in standard measurements of student learning in traditional classroom settings when constructivist instruction techniques are skillfully applied as opposed to its traditional counterpart, direct instruction. The purpose of this study is to apply the concept of constructivism in musical instruction. The working hypothesis is...
The natural production of methane via anaerobic digestion (AD) is facilitated by a complex community of microorganisms, primarily bacteria and archaea, referred to as the AD microbiome. AD is growing in prominence as a solution to the disposal of food waste, sewage sludge, and the organic fraction of municipal solid...
The total kinetic energy (TKE) in the fast neutron induced fission of 237Np was measured for neutron energies from En = 2.6 – 45.7 MeV at the LANSCE- WNR facility. The postTKE release decreases non-linearly with increasing incident neutron energy and can be represented as TKE(MeV) = (169.365 ± 1.551)...
Five varieties of industrial hemp (Cannabis sativa) were grown in the field in Imperial Valley, CA, USA in order to determine whether light conditions or harvest times influence cannabinoid content. A total of 16 cannabinoids were investigated in this study: Delta-9-tetrahydrocannibinol (THC-d9), Delta-9-tetrahydrocannibinolic acid (THC-a), Cannabidiol (CBD), Cannabidiolic acid (CBD-a),...
Over 470 dams have been removed in the United States, and a significant increase in dam removals has
occurred since the early 1990s. The aging of dams is often cited as the primary factor influencing removals;
as dams surpass their functional life span, safety hazards, economic costs, and environmental concerns...
The debate over GM crops is one of the most controversial issues of recent decades. The debate has many dimensions, including environmental impacts, benefits and risks to human health, intellectual property rights, adequacy of biosafety regulations, and fundamental ethical acceptability. The potential benefits of GM crops are numerous, including improved...
Community births are defined as a planned home or birth center birth. Today, the majority of births in the U.S. occur in the hospital, but the U.S. has the highest maternal mortality rates of any developed country. Although community births have comparable outcomes, there is an extreme preference for hospital...
Piezoelectric materials convert mechanical strain into a dielectric displacement, as well as the converse, allowing these materials to be used as sensors, actuators, and transducers. Currently, lead zirconate titanate (PZT) is the primary material used in these applications. Due to environmental toxicity and safety concerns associated with Pb, development of...