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CB1 Receptor Involvement in Contextual Cocaine Memory Reconsolidation
No full textThesis (Ph.D.), Neuroscience, Washington State UniversityEnvironmentally induced cocaine relapse is a major impediment in the treatment of substance use disorders. Re-exposure to a cocaine-associated context can trigger the retrieval of context-cocaine memories which renders these memories unstable and temporarily susceptible to modification before they are restabilized through memory reconsolidation. This process is dependent on gene transcription, de novo protein synthesis, and synaptic plasticity. Importantly, targeted interference with this process can weaken maladaptive context-drug associations and reduce the propensity for relapse. Therefore, identifying the neurobiological mechanisms underlying this process is of timely importance from a treatment perspective. Accordingly, this dissertation elucidates the involvement of cannabinoid type 1 receptor (CB1R) signaling in context-cocaine memory reconsolidation. To this end, we used an instrumental model of context-induced cocaine relapse to test the hypothesis that CB1R signaling modulates neuroadaptation during memory reconsolidation and subsequent drug-seeking behavior. Specifically, we demonstrated that CB1Rs are functionally necessary during memory reconsolidation, and we examined whether CB1R signaling is necessary for memory reconsolidation-associated molecular and synaptic adaptations in the basolateral amygdala (BLA). In subsequent experiments, we examined whether CB1R subpopulations in the BLA and dorsal hippocampus (DH) critically mediated memory reconsolidation and coinciding hypothalamic pituitary adrenal
axis activation. Together, the results of this dissertation provide novel support for the CB1R as a therapeutic target for relapse prevention.Washington State University, Neuroscienc
Minimal Homotopies And Robust Feasibility Using Topological Degree Theory
No full textThesis (Ph.D.), Mathematics, Washington State UniversityMinimal Homotopies
This study considers the set of homtopies between homotopic continuous maps
from compact submanifolds of Rd into Rd+1 s.t. the closed neighborhood around
any point in the range can be defined as the intersection of bounded d-manifolds.
Namely homotopies between such maps that agree along their non-empty boundaries
and are homotopic relative to their boundaries. We further restrict our study
to such maps that individually and jointly have only “simple” crossings or intersection
sets that are d 1-manifolds.
The goal of this study is to develop a rigorous framework for describing the
properties a “minimal homotopy” within this set of homotopies would possess,
should one exist. Informally we can think of a homotopy between two such continuous
maps with equal boundary as minimal if it sweeps “minimal volume” in
comparison to all other valid homotopies of its kind. This study develops a number
of such structural properties including those concerning existence.
Robust Feasibility
We consider the problem of measuring the margin of robust feasibility of solutions
to a system of nonlinear equations. We study the special case of a system of
quadratic equations, which shows up in many practical applications such as the
power grid and other infrastructure networks. This problem is a generalization of
quadratically constrained quadratic programming (QCQP), which is NP-Hard in
the general setting. We develop approaches based on topological degree theory
to estimate bounds on the robustness margin of such systems. Our methods use
tools from convex analysis and optimization theory to cast the problems of checking
the conditions for robust feasibility as a nonlinear optimization problem. We
then develop inner bound and outer bound procedures for this optimization problem,
which could be solved efficiently to derive lower and upper bounds, respectively,
for the margin of robust feasibility. We evaluate our approach numerically on standard
instances taken from the MATPOWER database of AC power flow equations
that describe the steady state of the power grid. The results demonstrate that our
approach can produce tight lower and upper bounds on the margin of robust feasibility
for such instances.Washington State University, Mathematic
RISK AND PROTECTIVE FACTORS IN ADOLESCENT MARIJUANA AND TOBACCO CO-USE: AN EXAMINATION USING VARIABLE- AND PERSON-CENTERED METHODS
No full textThesis (Ph.D.), Human Development, Washington State UniversityAdolescents often use substances such as tobacco and marijuana. Co-use of these substances can lead to physical, mental, and psychosocial difficulties beyond that which would be anticipated by simple additivity of their individual effects. Using mediation analysis (study one), moderated mediation analysis (study two), and latent class/profile analysis with a distal outcome (LPA; study three), this dissertation examined relationships between youth factors (internalizing, externalizing, and sensation seeking), age at first use of tobacco or marijuana, family factors (curfew, rules about tobacco product use in the home, availability of tobacco, parent talk about not using tobacco, expected parent reaction to tobacco use, and household tobacco use), and use and co-use outcomes in models representing lifetime and past 30-day use.
Relationships were present between each youth factor (internalizing, externalizing, and sensation seeking) and lifetime tobacco and marijuana co-use in study one. For past 30-day use, externalizing and sensation seeking had significant associations, internalizing did not. Study two built upon these relationships - family factors of expected parent reaction and parent talk about tobacco use moderated paths leading to co-use. In study three’s LPA, five classes were present: 1) Family Risk, 2) Very Low Internalizers with Family Protection, 3) Internalizers with High Family Protection, 4) Above Average Youth Risk with Family Protection, 5) Internalizers with Family Risk. Each of these classes was differentially related to tobacco and marijuana use outcomes. The item probability patterns and relationships with the outcomes directed focus to the importance of the family factors of household tobacco use, availability, and rules about use in the home.
Future studies should provide a more detailed view of the functioning of the home, including details about conversations between parents and youth, and youth behaviors. Based on the results of these three studies, I recommend that 1) an LPA of a more comprehensive set of youth factors with a distal substance use outcome and examination of potential moderation of these relationships by explicitly defined family factors be conducted, and 2) prevention and intervention programming address youth externalizing, sensation seeking, and family environment to be most effective.Washington State University, Human Developmen
The American Frontier and the Scottish Fur Trade in the Pacific Northwest
No full textThesis (Ph.D.), American Studies, Washington State UniversityThe French and Indian War opened up the fur trade for Scots. They developed their own “model” of country marriage that evolved into a horizontal “clan” system stretching across the continent. Scots “married-in” to Native communities and encouraged other employees, including the French Canadians and Hawaiian kanaka laborers and their own Scots-Indian sons to do likewise. They married their daughters to newcomers, thereby bringing them into the network as well. This pattern can be identified by researching fur trade genealogies. Over time dowries replaced bride prices and marriage became a formal affair, written contract, before a justice of the peace or in a church rather than an oral agreement.
European fathers began to employ ideological institutions like schools and church which taught their daughter to act according to social standards such as the “Cult of Domesticity.” Native women had had a long history of adapting European trade goods into Native fashion and altering their traditional clothing styles to accommodate new lifeways, but now the daughters were expected to dress according to their European social status. The daughters of the country were now seen as assimilated and to have “married-out” of their Indian cultures and into the Euro American culture. In order to move Indian lands into the trade network and thereby the public sphere these mixed-blood women were considered assimilated and these European-Indian marriages were deemed legal and binding
Americans traveled across the North American continent expecting to find an empty wilderness in which to plant their own version of the Puritans “city on the hill.” They took with them ideologies about the frontier, wilderness, and Indians, especially the “Indian Princess.” Captivity narratives had been used by the Puritans to establish social conformity and their morality code continued to permeate American lives 200 years later as thousands left the United States for the Pacific Northwest. Rather than a barren wilderness they found an already established agricultural community operated by the London based Hudson’s Bay Company. This “imagined community” had schools, churches, a cemetery, a lumber mill, produced grain and had a mill, as well as orchards, gardens, and livestock.Washington State University, American Studie
Diet and Nutrition Among the Confederated Tribes of the Chehalis Reservation
No full textThesis (Ph.D.), Anthropology, Washington State UniversityThe purpose of this study is to document the ethnohistory of nutritional trauma and understand resiliency responses among the Confederated Tribes of the Chehalis Reservation. What local strategies and responses to nutritional trauma lead to positive health outcomes? This research will help identify the positive responses and strategies to nutritional trauma within the community to build upon and find community solutions to address the lingering health problems caused by nutritional trauma. Nutritional trauma involves the disruption of access to indigenous natural foods and medicines as a result of imposed and overwhelming external forces including development, introduction of agriculture, deforestation, environmental destruction, contamination by toxic wastes, pesticides and herbicides, and the imposition of land tenure laws that to a great extent exclude native ownership (Korn and Ryser 2005). Nutritional trauma is a subset of community trauma and historical trauma. “The historical experience of culture groups exposed to prolonged stress and suffering resulting from war, genocide, interpersonal violence triggers the ‘transfer’ of physiological, biological, and emotional stress to successive generations” (Korn and Ryser 2009).
The data consisted of 40 interviews collected between September and December 2018. Correlation tables and logistic models (full model and step-wise model) were used to understand the data. The findings indicated 1.) there were no significant associations between the access variables and nutritional illness, 2.) growing up on the reservation was negatively correlated with reporting a nutritional illness, 3.) fitness was significantly associated with reporting a nutritional illness and 4.) having a family member that suffered from a nutrition related illness increased the likelihood of an participant reporting a nutritional illness. Today, the Chehalis tribe is actively working to repair the trauma to heal the soul wound. The reservations which once pained Native Americans can be transformed into sources of power and resilience today. Tribal members demonstrated resiliency in a number of ways including: participating in cultural events, learning and utilizing traditional ecological knowledge, using humor to connect and cope, knowledge and use of community resources, having a strong social network of friends and family, as well as, other personal practices, motivations, and desires to engage in healthier lifestyle practices.Washington State University, Anthropolog
Query-driven Exploration of Big Graphs
No full textThesis (Ph.D.), Computer Science, Washington State UniversityExploring graph-structured data either by mining or querying is a fundamental operation
that enables important applications including knowledge
graph search, social network analysis, and cyber-network security.
Given the proliferation of complex data in the forms of large-scale heterogeneous and dynamic graphs, it is preferable while difficult to revisit traditional query-response paradigms. Graph query construction is a daunting task and typically requires multiple iterations either due to the complexity of the
schema, unfamiliarity to the data, or not having pre-determined goals. To ease the access and consumption of such rich information, there is a need to complete the existing graph-based analytical systems for exploration.
In response to this requirement, the dissertation focuses on the problem of query-driven graph exploration and develops a framework to aid users in exploration of both static and dynamic graphs. Query-driven exploration allows the users to explore a fraction of the data by providing a desired but potentially incomplete analytical query (e.g. keywords, graph pattern query). It then retrieves answers to the initial query in the hope of obtaining feedback such as an updated query, examples of desired answers, or questions on why the results are not satisfactory. By focusing on interesting fraction of the data, query-driven graph exploration meets the usability and response-time requirement of real-world applications. It reduces the excessive results that may be retrieved by conventional graph mining techniques, decreases the irrelevant answers to the users' needs, and improves efficiency by e.g. local search. Hence, to support effective graph exploration with keywords as a user-friendly tool, the thesis first introduces cost-aware keyword exploratory search. Second, by proposing a class of event patterns that pertains to a set of keywords, the thesis extends exploration to the dynamic graphs. It then develops incremental algorithms to detect such patterns and the association rules among them. Finally, to aid users debugging their pattern queries by asking why the results are not satisfactory, a set of algorithms are developed. The thesis
experimentally verifies the efficiency and effectiveness of the proposed approaches using real-life graphs.Washington State University, Computer Scienc
Habitat mapping and multi-scale resource selection of pygmy rabbits with unmanned aerial systems
No full textThesis (Ph.D.), Environmental and Natural Resource Sciences, Washington State UniversityAssessing habitat quality is a primary goal of ecologists. However, evaluating habitat features that relate strongly to functional habitat quality at fine-scale resolutions across broad-scale extents is challenging. Unmanned aerial systems (UAS) bridge the gap between relatively high spatial resolution, low spatial extent, field-based habitat quality measurements and lower spatial resolution, higher spatial extent satellite-based remote sensing. In chapter one, I mapped structural habitat quality (i.e., shrub height, shrub volume, and aerial concealment) at two study sites with UAS and compared that with estimates derived from terrestrial laser scanning, a highly accurate ground-based sensor. I demonstrated that UAS was able to accurately estimate habitat heterogeneity for a key terrestrial vertebrate at multiple spatial scales. In chapter two, I classified sagebrush structural morphotypes and mapped forage quality including both nutrients (i.e., crude protein) and plant secondary metabolites (i.e., coumarins and monoterpenes) with UAS in both summer and winter. With these maps, I generated foodscapes representing high and low forage quality for herbivores that use sagebrush landscapes such as the sagebrush-obligates, pygmy rabbits (Brachylagus idahoensis) and greater sage-grouse (Centrocercus urophasianus), and generalist herbivore mountain cottontails (Sylvilagus nuttallii). In chapter three, I analyzed habitat selection by pygmy rabbits at multiple scales. I found that pygmy rabbits select for food variables (i.e., crude protein and total monoterpenes) while foraging (bite marks) at the plant scale, and selected for both security cover (i.e., aerial concealment and distance to burrow) and food variables at the patch scale. While moving and resting (fecal pellets), pygmy rabbits selected for a combination of food, security, and thermal properties, with thermal variables appearing more frequently in top models at the plant scale, and primarily for security at the patch scale. Finally, I applied my patch-scale model of pygmy rabbit habitat selection across the landscape using UAS-derived maps of security cover and food quality. These results show scale-dependent habitat selection in a central-place browsing herbivore. Making explicit predictions of trade-offs affecting habitat use, and assessing those predictions at distinct scales, will be necessary for improving knowledge of habitat selection patterns in herbivores.Washington State University, Environmental and Natural Resource Science
FAULT RESILIENT POWER SYSTEM THROUGH HIERARCHICAL CONTROL OF ENERGY STORAGE SYSTEMS AND FACTS DEVICES
No full textThesis (Ph.D.), Electrical Engineering, Washington State UniversityThe control of large-scale power systems is hierarchical in terms of actions taken and their response time. For a system subject to faults, primary control actions are taken immediately to maintain the stability of the network in a time scale as small as microseconds. Automatic control also consists of secondary control which tries to bring the system into normal operating state. Secondary control scheme ensures that proper remedial control actions are taken after a short period of fault occurrence to bring the network operating limits to secure ranges.
Primary control schemes are mainly based on available control options at the generating units such as governor and excitation control of synchronous generators. However, for a given power system only one control action might not be adequate in case of sever contingencies. As new elements such as energy storage system (ESS) are being added to the grid, a unified control algorithm is required to coordinate the available control options at the generating units and maintain the system stability. This dissertation investigates the integration of ESSs to generating substations and develops a coordinate framework for ESS and synchronous generator controllers to enhance the transient stability of the system. A slower control scheme is also developed which performs corrective actions in order to ensure secure ranges for network operational limits and bring the system back to normal operating point. The proposed corrective algorithm exploits a piecewise linear approximation of optimal power flow problem to coordinate available control option including generator rescheduling, load shedding, and controlling FACTS devices.Washington State University, Electrical EngineeringBy student request, this dissertation cannot be exposed to search engines and is, therefore, only accessible to Washington State University users
Archived data for Watts et al. 2019 Anim Mig
No full textThe document, "Watts et al 2019_AnimMig_Dataset.csv," contains the data from pine siskins (Spinus pinus) used in the paper: Watts, H. E., Rittenhouse, J. L., Sewall, K. B. & Bowers, J. M. 2019. Migratory state is not associated with differences in neural glucocorticoid or mineralocorticoid receptor expression in pine siskins. Animal Migration 6: 19–27
