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Geospatial frameworks for predicting the distribution of keystone aquatic invaders : local to global implications
No full textBiological invasions can profoundly alter ecosystems, particularly when invaders hold the potential to exert disproportionate effects on occupied environments (sensu keystone species). However, addressing the spatial-temporal extent of invasions and generating actionable insights for their management remains a significant challenge for ecologists. Here, I offer a suite of spatially explicit computational models to gauge the risks associated with introducing species, focusing on the interplay between species-specific, environmental, and human drivers of invasions. I apply these models across various regions and species, emphasizing salmonids. Firstly, I assess the environmental resistance to invasions of non-native Pacific salmon and North American beavers in Patagonia through a novel implementation of the Habitat Intrinsic Potential model, modified to address multiple life stages. Secondly, I study two major Atlantic salmon escapes from aquaculture facilities in the Pacific regions of North and South America, leveraging them as natural experiments of post-escape dispersal and use of potential habitats within neighboring river systems. Thirdly, using a pioneering ecophysiological model, I map potential marine habitats for three salmon species presenting mixed success in the Southern Hemisphere (Chinook salmon Oncorhynchus tshawytscha, coho salmon O. kisutch, and Atlantic salmon Salmo salar) and test hypothesized roles of the marine environment in shaping invasion outcomes. Our findings underscore the complex interplay of environmental and species-specific factors governing spatial-temporal dynamics of non-native aquatic species. Keystone aquatic invaders, such as salmon and beavers, exhibit spatially varied and temporally dynamic distributions driven by heterogeneities in environmental regimes. Regions that offer diverse habitats catering to different life stages, especially in both freshwater and marine settings, were here interpreted as areas of heightened invasion risk. Propagule dispersal upon introduction was considered a crucial determinant of invasion success and management challenges. Lastly, I identify key research avenues that could enhance our understanding and management of such high-risk invasions, emphasizing the importance of systematic field monitoring and strategic interventions. This project integrates principles from fish biology, invasion biology, landscape ecology, and geography, aiming to bridge knowledge gaps hindering the management of high-risk invasions in delicate but data-poor aquatic ecosystems
Uncovering the AI-copyright trap
No full textAs AI tools proliferate, law and policy makers are being called upon to protect creators and the cultural industries from the extractive, exploitative, and even existential threats posed by generative AI. Professor Carys Craig warns that, in our haste to act, we risk running headlong into a copyright trap. In this presentation, Craig will explain what she means by the “AI copyright trap”, the routes by which it draws people in, and why it threatens to obstruct the path towards responsible and ethical AI. (Note: Presentation delivered online on August 26, 2025, as part of the AI Literacy Center's programming)
Wideband Frequency Modulated Continuous Wave (FMCW) Radar Transceivers with Self-Interference Cancellation at mm-Wave and X-band
No full textFrequency Modulated Continuous Wave (FMCW) radar technology has become indispensable across numerous fields due to its capability to simultaneously measure range and velocity with exceptional accuracy. This technology is particularly critical in the automotive industry, where millimeter-wave FMCW radars are integral to advanced driver assistance systems (ADAS). Beyond automotive uses, X-band FMCW radars are extensively employed in synthetic aperture radar (SAR) systems for earth observation and remote sensing. The versatility of FMCW radar also extends to medical and healthcare applications, where it is utilized for non-contact vital sign monitoring, such as detecting heartbeats and respiration rates.
However, the simultaneous operation of the transmitter (TX) and receiver (RX) within the same frequency band—while beneficial for bandwidth efficiency and increased system data rates—results in a portion of the strong TX signal leaking into the RX path, creating self-interference (SI) that degrades system performance.
In this work, two novel self-interference cancellation (SIC) methods are proposed and applied to millimeter-wave and X-band FMCW radars. These methods are designed to mitigate the trade-off between RX linearity and noise figure caused by TX self-interference. The focus is on minimizing noise degradation from the added SIC path while managing large TX SI signals. Additionally, a wideband FMCW radar transmitter is presented, showcasing state-of-the-art performance for high-resolution radars at both X-band and millimeter-wave frequencies
Stable statewide cash rents for Oregon agricultural land mask large changes across counties in 2024
No full textThis is an annually updated article based on the US Department of Agriculture's cash rent estimates. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
The role of science and values in collaborative forest management : a case study of timber salvage and Canada lynx in beetle-impacted spruce-fir forests of southcentral Colorado
No full textThis paper seeks to provide additional insight into these questions by exploring a case study in the management of beetle impacted spruce-fir forests in southcentral Colorado under a multiple-use mandate. Semi-structured interviews of natural resource professionals that were involved in the case study were conducted. A contextual analysis was also drawn from information provided in the interviews to produce a multifaceted analysis of the circumstances that formed the setting of the case study and how those circumstances evolved over time. This contextual analysis obtained interviewee feedback in how best available science was integrated into management by way of agency collaboration. Furthermore, participant interviews will illuminate perspectives about how values impact management while also identifying challenges, limitations, needs, and opportunities for improvement that were most impactful to their work. Exploring perspectives from natural resource professionals gives invaluable insight that may assist agencies in more efficiently addressing present and future challenges
Toward sustainable metal forming : cost and environmental evaluation of single point incremental forming
No full textGiven the slow adoption of incremental sheet forming as an alternative to conventional metal forming processes, researchers and practitioners must integrate broader considerations that can clarify the path toward implementing sustainable manufacturing alternatives. However, predicting the costs and environmental impacts of flexible sheet forming processes, such as single-point incremental forming (SPIF), presents challenges due to the use of unconventional tooling and attachments that have not yet been thoroughly analyzed in previous studies. Thus, this study comprehensively reviewed SPIF, integrating the costs and environmental impacts of all elements necessary for part production through a case study (and its performance indicators at various production volumes) and detailing of the adjacent process steps to the forming process. The findings indicate that the pre- and post-forming stages for SPIF have lower economic and environmental impacts than the forming process at 50, 500, and 5,000 parts per year. This study identified that a significant factor influencing the utilization of SPIF at larger production volumes on manufacturing floors is the labor cost associated with longer cycle times in the contemporary process implementation approach.
Considering these insights, further research should focus on quantifying the cost and environmental impacts of tooling developments for SPIF and exploring strategies to reduce labor costs, which could enhance the adoption of SPIF in manufacturing. This thesis fulfilled the stated research goal in Chapter 1 by completing the following tasks:
• Developing a cost model for SPIF part production that allowed the inclusion of necessary consumables, such as clamping fixtures and forming tools. This approach enabled a more accurate prediction of the cost of goods sold (COGS) during the early stages of production planning.
• Developing a UPLCI model for SPIF that enabled the inclusion of relevant process parameters, such as toolpath length and forming feed rate, to improve performance prognostics. Laboratory experiments validated the model, demonstrating an accuracy between 92% and 100%, making it a valuable tool for life cycle assessment studies of the SPIF process.
• Conducting a comparative analysis of the cost and environmental impacts of SPIF and traditional metal drawing, including examining the process steps before and after forming, as well as the required machine tools. A sensitivity analysis validated the results by exploring variations in significant factors identified in the model. This comprehensive analysis highlighted the high labor costs for both forming processes and emphasized the need for reducing cycle time in the SPIF process.Keywords: UPLCI,
Single Point Incremental Forming,
Life Cycle Assessment,
Cost Modeling,
Cost and Environmental Impact Assessment,
Sheet Metal Formin
Leveraging incentive-based programs to protect the Peruvian Amazon: Lessons learned for Stakeholders
No full textThe Amazon Forest of South America provides a wealth of ecosystem services with far-reaching benefits, especially in reducing the effects of increased CO2 emissions on our climate through carbon sequestration, but continuous deforestation and forest degradation in the region are intensifying the effects of climate change across the planet. Given the high environmental, economic, and social importance of the Amazon Forest, decision-makers, scientists, researchers, local communities, and others worldwide are under pressure to address the drivers of deforestation and forest degradation. Forests of the Madre de Dios region in the Peruvian Amazon face threats from small-scale agriculture, logging, and mining activities. There are many incentive-based forest conservation programs that seek to promote sustainable forest activities while simultaneously supporting the economic development of local and Indigenous communities, as in the case of Brazil nut production. Although progress has been made through these initiatives in the last two decades, the results still fall short of expectations. Through a literature review of project assessments for REDD+ (Reducing emissions from deforestation and forest degradation), PES (Payment for ecosystem services) initiatives in Madre de Dios, several common barriers and challenges were found, which include land tenure insecurity, a lack of cross-sectoral coordination in forest policies, weak governance, inadequate funding, a need for capacity-building at the local level, inadequate payment structures and monitoring and sanctioning systems, and a lack of forest and socioeconomic data, among others. The literature review also focused on recommendations and lessons learned from past and previous programs to help overcome these challenges. These include forest policy reform, improved mechanisms for granting concessions, cross-scale capacity-building, prioritization of granting land rights for Indigenous communities and their inclusion in program design and implementation, increased governmental support for CFM, and spatial targeting, differential payment systems, and improved monitoring mechanisms to ensure conditionality and increase efficiency
The Acute and Chronic Effects of Micro and Nanoplastics on the Development and Reproduction of Freshwater and Marine Model Organisms
No full textMicro- and nanoplastic pollution is of growing concern. Annually, an estimated 10-20 million metric tons of plastics are released into the environment, a value which is expected to continue to increase. This dissertation begins with a thorough review of the micro- and nanoplastic literature, highlighting the ways in which microplastic research can contribute to addressing gaps in nanoplastic knowledge, as well as the ways in which these gaps should begin to be filled experimentally. The subsequent chapters cover four studies that investigate micro- and nanoplastic toxicity to aquatic model organisms while defining exposure conditions in a way that generates high-quality, dose-response data for risk assessment. The second and third chapters cover more well-studied plastic beads, and the following two chapters examine plastic fragments that more closely mirror particles in the environment. Chapter 2 demonstrates the use of an exposure system optimized for both particle suspension and larval mussel growth and survival to assess impacts of microplastics. We demonstrated that reduced nutrient uptake is a dominant effect mechanism for microplastic impacts on early development of larval bivalves. Chapters 3-5 detail the toxicity of micro- and nanoplastics to freshwater model organisms (zebrafish and Daphnia), demonstrating that chronic exposures reveal toxicity that is overlooked with acute exposures alone. This body of work not only emphasizes the importance of clearly defined exposure conditions, but highlights the variation in plastic toxicity between different affected species, as well as conspecifics exposed to plastics of varying sizes, morphologies, and compositions
Playing for a Purpose? A Qualitative Exploration of How Individuals Develop Purpose in Life Through Sport
No full textPurpose is a personally meaningful aim that one ascribes to their life. Given the long term mental and physical benefits associated with purpose, youth should be supported as they explore what is personally meaningful to them. While youth describe sport as purposeful, it is unknown how individuals come to develop purpose through sport. The aim of this study was to determine how, and under what circumstances, sport helps cultivate purpose. This study utilized a narrative inquiry methodology. Twelve participants (men = 6; women = 6) were committed to their respective purposeful youth sport based work (e.g., coaching, physical education). Each participant shared their life story via two in-depth interviews. A narrative analysis was conducted of the data. Results indicate that the development of purpose through sport is a function of how one views their future self in relation to their sport environment. Themes developed in the current study include the following: (1) Participants only began to develop purpose through sport when they had access to the sport environment. (2) Participants cultivated a sense of agency, identified as an athlete, and imagined their future self in sport. (3) Participants derived personal meaning while obtaining further access to sport-based opportunities. (4) Participants’ respective purposes in sport evolved over time as they gained more knowledge. These findings elucidate how sport can be utilized to facilitate the cultivation of purpose
Microbial Communities Shape Chemical Fate During Wastewater Treatment: Implications for Low-Cost Treatment Optimization
No full textThis dataset includes chemical and microbial analysis data from three conventional biological wastewater treatment utilities. It contains raw non-targeted liquid chromatography-mass spectrometry (LC-MS) data in various formats, including MZxml, timeseries, wiff, wiff2, and wiff.scan, as well as annotated 16S rRNA amplicon sequencing data in fastq format. The dataset provides comprehensive documentation of each file type, sample names, as well as the methods used for data collection and processing. This data is intended to support further research on chemical degradation and microbial catalyzers in wastewater treatment systems. For specific details on the experimental setup, sampling protocols, and data analysis methods, please refer to the associated manuscript. (https://doi.org/10.1021/acsestwater.5c00660)