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Assessing the Climate Resilience of \u3ci\u3eQuercus garryana\u3c/i\u3e in the Portland Metro Region
No full textIn the context of rapid global climate change, understanding the resilience of local tree species is essential for fostering effective environmental stewardship and community hopefulness. Oregon white oak (Quercus garryana), an emblematic species in the Pacific Northwest, has faced significant habitat loss and degradation since settler colonization. However, it also exhibits a predicted resilience to climate change, potentially leading to a range shift and expansion. Species resilience refers to the capacity of a species to persist and adapt in the face of rapid global climate change. Beyond vulnerability assessments and niche models, we know little about this species\u27 ability to adapt at varying timescales. This dissertation addresses these gaps in scientific knowledge of climate change impacts on Oregon white oak. It specifically addresses the species\u27 overall adaptive capacity, phenotypic plasticity, and drivers of regeneration in its now highly urbanized environment. I address these gaps while recognizing that integrating Indigenous Traditional Ecological and Cultural Knowledge (ITECK) and respectful collaboration by land managers is key to the species\u27 adaptive management.
My dissertation begins with a trait-based range-wide adaptive capacity assessment of Oregon white oak that integrates historical management narratives. The assessment reveals the species\u27 vulnerabilities and strengths in adapting to climate change, emphasizing important traits related to evolutionary potential and how they can aid in species adaptation.
To further our understanding of how this species can adapt at shorter timescales, I explore what is known about plant phenotypic plasticity in a changing climate and present results on a climate factorial experiment conducted with Oregon white oak seedlings. These results are contextualized for land managers to help further our understanding of how phenotypic plasticity may be used and understood in a changing climate for plant materials selection.
Further, I delve into drivers of oak regeneration in high conservation priority urban and fragmented habitats within the Portland metro region. This field study identified landscape, community, and climate-level variables influencing the different age classes of oaks, providing insights for restoration and management decisions. The findings underscore the significance of habitat quality, connectivity, and community structure in supporting oak demography.
Bridging gaps in knowledge and emphasizing what Indigenous Peoples have shared about climate adaptation, this dissertation contributes to a comprehensive understanding of Oregon white oak\u27s resilience. I end by emphasizing the necessity of collaborative approaches between Indigenous knowledge holders and Western scientists for effective climate adaptation strategies and increasing ecosystem resilience.
This dissertation aims to encourage local land managers to integrate climate adaptation and to make space for Indigenous people to practice ITECK as part of land management practices. To do this, Western land managers and scientists will have to overcome barriers of epistemology and embrace interdisciplinary work along with new ways of approaching restoration. Although this dissertation focuses on a single tree species, the study of Q. garryana resilience in the face of global climate change represents a crucial step in our regional understanding of climate adaptation and mitigation. Oregon white oak is beloved by many, and its climate resilience can be a symbol of hope for people to embrace climate adaptation strategies in times of ecological uncertainty
Experiences of Community College STEM Students in Transferring and Adapting to a Four-Year Urban University
No full textEnsuring that the bachelor\u27s degree pathway that begins at a community college is a robust option for science, technology, engineering, and mathematics (STEM) students will be key for addressing the calls to increase and diversify the future STEM workforce. Yet, students on this pathway currently face many structural barriers that can lead to attrition. In this work, we aim to understand the experiences of community college students as they transfer, adapt, and persist to graduation at an urban four-year university.
First, we used the Model for Analyzing Human Adaptation to Transition to explore the experiences of community college STEM students as they transferred to an urban four-year university. Through analyzing focus groups conducted with students post-transfer, we developed the Amended Model of Adaptation to Transfer Transition (AMATT). The AMATT displays characteristics that impacted the students transition under three categories: perception of the transition, environmental characteristics, and individual characteristics. We also identified two key pathways of adaptation: surviving or thriving. Within the AMATT, we illustrate which factors contributed to each pathway of adaptation and demonstrate the relationships between the characteristics under each category.
We then aimed to develop a deeper understanding of how STEM transfer students adapt to the transition to the university. Drawing from the AMATT, we chose three key factors that supported a thrive adaptation to investigate further: sense of belonging, social capital, and science identity. To explore how a sense of belonging may be cultivated post-transfer, we conducted interviews with a group of STEM transfer students as they neared graduation. We leveraged the Network Theory of Social Capital and Counterspaces Framework to guide our analysis and found evidence of both the elements of social capital and counterspace processes supporting the development of a sense of belonging for these transfer students.
Continuing in our investigation of factors that supported a thrive adaptation, we again utilized the Network Theory of Social Capital to examine how a group of community college transfer students developed social support post-transfer. We conducted interviews with a second group of STEM transfer students as they neared graduation and found that social capital actions facilitated the development of relationships that provided social support post-transfer. Connections made with peers were primarily facilitated through expressive actions (i.e., emotional support), while connections made with faculty were primarily facilitated through instrumental actions (i.e., structural support).
The last factor that we consider from the AMATT that supported a thrive adaptation is science identity. We conducted interviews with transfer students after their first-year post-transfer and used the Possible Selves Framework as a guide in our analysis. We found evidence of multiple experiences that supported the student\u27s development of a science identity, with an interdisciplinary research-based course having an outsized effect on their identity development. Through this work, we provide insight into the complexity of the transition experience for community college students in the STEM fields and demonstrate how groups of persisting transfer students developed factors that support a thrive adaptation post-transfer
The Arab Spring Uprisings in Geopolitical Context
Get PDFThe question of why revolts, civil wars, and social unrest occur is central in the field of political science. This paper asks that question in the specific context of the 2011 Arab Spring uprisings as a revolutionary wave. Many theories of revolution and social unrest locate their causes in the internal characteristics of the country where they take place, such as the country\u27s demographics or level of economic development. This paper examines the external situation of a country: its relationships with other states and the international community. This paper examines eighteen Arab countries in the Middle East and North Africa (MENA) region and compares the severity of the unrest in 2011 in each country with the general international attitude toward each country\u27s government. Compared with various internal characteristics of each country, this paper finds a fairly strong statistical correlation between the severity of unrest in a country and the negativity of the international attitude toward that country, suggesting that the foreign attitude and indirect foreign influence are significant causes of revolutionary upheaval in many countries
Co-Designing with First-Generation Transfer Students
Get PDFRoughly 80% of community college students indicate that they intend to transfer to a four-year institution, 30% of those students eventually transfer, and 13% of those students persist to graduate with a baccalaureate degree. There has been previous research on transfer students and on first generation students, but the intersection of first-generation transfer students is under-reported. Prior research indicates that sense of belonging is an important factor in student persistence to graduation for transfer students. Higher education institutions, specifically four-year public institutions, are positioned to support first-generation transfer student sense of belonging by fostering a transfer receptive culture. Recognizing that students are experts in their own experiences, design thinking strategies are employed to co-create services to support sense of belonging; however, the experience of the students who participate in co-design activities has not been researched. The purpose of this qualitative exploratory case study was to understand the experiences of nine first-generation transfer students who participated in co-design of programs and services aimed at fostering a transfer receptive culture at Portland State University. Through observations of co-design sessions, analysis of visual data, and semi-structured interviews with participants, the researcher found that the co-design process engaged first-generation transfer students and enhanced their sense of belonging through validation of their identities and experiences; validation of participants\u27 identities and life experiences shaped their participation in the co-design process as experts; and co-design of programs and services with first-generation transfer students must include action as part of the process
Design and Test of Asynchronous Systems Using the Link and Joint Model
Get PDFAsynchronous circuits offer numerous advantages, including low energy consumption and good composability and scalability. However, they remain meagerly adopted in the mainstream semiconductor industry. One reason is the limited number of design tools available to help designers navigate design complexity, particularly the myriad of asynchronous implementation styles.
This dissertation focuses on managing the myriad of asynchronous implementation styles by utilizing a circuit-neutral model, called Links and Joints, and embedding this Link-Joint approach into a design flow. Although years of past work have already laid the groundwork, the work in this dissertation identifies and addresses key missing pieces.
First, the dissertation presents a design and test methodology centered around Links and Joints that exploits the similarities between multiple circuit implementation styles. This methodology offers interface uniformity and generality for various asynchronous circuit families and protocols, as well as flexibility in implementation choices and circuit initialization.
Second, this dissertation shows the Link-Joint methodology embedded in a design flow. The resulting flow, called Ọnà (/or-NUHR/, Yoruba for way ), includes compilation and refinement steps for transforming high-level parallel programs with message passing via circuit-neutral Link-Joint networks into asynchronous circuits, postponing choices in protocol and circuit family as late as possible. Ọnà also carries along test and debug, using a uniform test approach that fosters test reuse from one abstraction level to another.
Ọnà makes it easy to insert asynchrony appropriate for each design part. The dissertation demonstrates this ease by providing methodology and design flow support for various protocols such as 2- and 4-phase protocols, level- and pulse- and transition signaling logic, bundled data, and circuit families such as Click, GasP, Set-Reset, Mousetrap, Micropipelines, and the Single Flux Quantum (*SFQ) superconductor family. The dissertation also demonstrates that mixing and matching different circuit implementation styles in Ọnà is flexible and straightforward
Oregon State Rank Assessment for Disappearing Monkeyflower (Erythranthe inflatula)
Get PDFOregon state conservation status assessment for Disappearing monkeyflower (Erythranthe inflatula) using NatureServe methodology, 2024
A Systems Theoretic View of Speculative Realism
Get PDFRecent developments in Continental philosophy have included the emergence of a school of “speculative realism,” which rejects the human-centered orientation that has long dominated Continental thought. Proponents of speculative realism differ on several issues, but many agree on the need for an object-oriented ontology. Some speculative realists identify realism with materialism, while others accord equal reality to objects that are non-material, even fictional. Several thinkers retain a focus on difference, a well-established theme in Continental thought. This paper looks at speculative realism from the perspective of systems theory. Many of the tenets of speculative realism have long been features of systems metaphysics and are expressed clearly in a systems framework. However, some views of some speculative realists differ substantially from systems theoretic ideas
Resource-constrained 2D Scene Recovery with Single-Photon Cameras
No full textThe modern world is built of images. However, in our goal to photograph and replicate what the human eye is capable of seeing, we are throttled by the restrictions of conventional imaging sensors in high- and low-illumination environments. Single-photon cameras (SPCs) have recently emerged as a promising alternative to conventional camera sensors for capturing images in challenging conditions such as high-dynamic range and fast scene motion. Compared to traditional CMOS cameras, SPCs exploit the arrival of individual photons rather than using an aggregate photon count to compute the brightness of pixels. However, SPCs are extremely resource-intensive, making them inconvenient for power-limited applications such as smartphones, mobile devices for augmented and virtual reality, low-power drones, and autonomous robots. In many imaging settings, we are restricted by the volume of photon data that can be stored and processed by individual pixels in large format (megapixel or larger) SPCs.
The thesis of our work is that SPCs can reconstruct high quality images with far fewer photons per pixel than previously thought necessary. To show this, we present an imaging pipeline including a resource-constrained multiplexing capture algorithm and a state-of-the-art deep learning-based denoiser method using transformers. In particular, we address a fundamental question in single-photon imaging---what is the minimum number of photons needed per pixel to construct an accurate image, and how few photons can one receive before an image is no longer recoverable? Our experiments on a large image dataset show that our pixel-sharing and post-processing denoising techniques can improve image quality by up to 5 dB peak-signal-to-noise ratio in low-light settings when compared to baseline capture methods. By allowing groups of pixels to share in-pixel memory and computing resources, our methods will lower the circuit and hardware complexity of future SPCs without compromising image quality
Working (around/within/against) Prior Appropriation: Diverse Hydrosocial Practices to Secure Water for Rivers
Get PDFWater scarcity in the Western US, through the lens of political ecology, can be understood as inextricably shaped by power dynamics, governance structures, and legal practices of resource allocation. Water allocation in the region is determined largely by the legal doctrine of Prior Appropriation, the \u27first in time, first in right\u27 principle. However, prior appropriation is fundamentally based in anthropocentric and settler colonial assumptions, and in light of drought, climate change, and shifting social and environmental values, the system has been critiqued as inadequate to meet contemporary water challenges. Despite challenging historical legacies, water managers in the Western US are developing a range of strategies to work around or within prior appropriation to secure environmental flows for rivers and aquatic species. In this article we use political ecology and diverse economies approaches to consider the challenges of, and challenges to, prior appropriation. We examine a diverse set of practices, work-arounds, and creative strategies being used to secure instream flows, and discuss how these strategies affirm or challenge prior appropriation, how they reinforce or challenge inequities, and how they reform or re-envision water allocation in ways that may open up potential for social and environmental justice
When Overextended Surface Allocation Turns to Groundwater: a Q Methodology of Well Users in Oregon’s High Desert
Get PDFAs legal battles over surface water allocation in Klamath County, Oregon, USA have gained national attention, earning the name “Water Wars,” authorities have been increasingly turning to groundwater to compensate for water shortfalls. This case study aims to identify the nuanced perspectives of household groundwater well users who are affected by groundwater extraction. Using Q methodology, we uncover groundwater well users’ perceptions and to what extent they think water problems are dealt with fairly. We identify four water perspectives that differ in the degree to which respondents prioritize clean water accessibility, industry accountability, individual responsibility for water management, and trust in governments to manage water competently. This research contributes to the growing body of literature reshaping our understanding of human-water relations by exploring different water axiologies