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Microbial diversity across spatial and temporal scales in high mountain watersheds of the Teton Range, U.S.A.
No full textUniversity of Minnesota Ph.D. dissertation. May 2025. Major: Plant and Microbial Biology. Advisor: Trinity Hamilton. 1 computer file (PDF); xv, 120 pages.Mountain ranges cover approximately 30% of Earth’s terrestrial surface and supply freshwater to human populations, globally (Milner et al. 2017; Moser et al. 2019). Beyond supporting humans, mountain watersheds (i.e. streams, rivers, lakes and upstream meltwater sources) are hotspots of biodiversity. In particular, mountain streams and lakes host diverse microbial communities in biofilms (Battin et al. 2016). These biofilms are primary sites of biogeochemistry and contribute to energy flow in montane food webs (Battin et al. 2016; Hotaling et al. 2017; Jorgenson et al. 2024; Michoud et al. 2025). Mountain stream biofilm communities are also increasingly threatened by climate change. Specifically, changes in meltwater supplies, temperature, and nutrient (e.g., nitrogen and phosphorus) concentrations threaten to reduce the presence of taxa adapted to historically cold and low nutrient conditions (Huss et al. 2017; Ren et al. 2019; Bourquin et al. 2025). Such changes may exert long-term declines in biofilm diversity and impact mountain ranges, globally (Ren et al. 2019; Oleksy et al. 2021; Brahney et al. 2022; Bourquin et al. 2025). A loss or shift in microbial diversity in mountain lakes and streams has far-reaching implications including: collapses in food web diversity, changes in water quality, loss of unique mountain specific adaptations, and altered biogeochemical cycles (Battin et al 2016; Hotaling et al. 2019; Busi et al. 2022; Kohler et al. 2022; Jansen et al. 2024; Ezzat et al. 2025). Yet, predicting how biofilm diversity will respond to climate change remains difficult because mountain lakes and streams are heterogenous ecosystems with strong spatial and temporal variation in environmental conditions that impact community structure and function (Wilhelm et al. 2013; Fell et al. 2021). For instance, differences in meltwater contributions (Hotaling et al. 2019; Brighenti et al. 2021), underlying bedrock porosity (Miller et a. 2021), and seasonality (Pernthaler et al. 1998) contribute to localized conditions that likely impact how microbial communities respond to change. Our ability to understand these ecosystems is further complicated by the fact accessing mountain lakes and streams is logistically challenging limiting the frequency and spatial resolution of sampling campaigns. Fortunately, due to accumulated datasets and collaborative efforts to conserve these regions (e.g. Hotaling et al. 2019; Jorgenson et al. 2024; Ezzat et al. 2025; Bourquin et al. 2025), we are now able to address and explore temporal and spatial processes influencing biofilm diversity. My dissertation contributes to these ongoing efforts by investigating biofilm diversity across space and time in alpine streams and mountain lakes of the Teton Range, Wyoming, USA.
For the first chapter of my dissertation, I investigated interannual biofilm diversity and composition in the Teton Range. From 2019 to 2022, I collected biofilms, in August, across alpine streams that may receive differing meltwater inputs. These meltwater inputs are a combination of ice, snow, rain, and groundwater that were categorized into three major stream types in the Teton Range by Hotaling et al. (2019). These stream types included glacier-fed, snow-fed, and icy seeps (i.e. subterranean ice melt). To assess interannual diversity, I used targeted amplicon sequencing for both bacteria and eukaryotes. The results from this chapter indicated both bacterial and eukaryotic diversity are correlated with environmental conditions in stream sites similar to other studies (Wilhelm et al. 2013; Hotaling et al. 2019). However, bacterial and eukaryotic composition did not change by site or with environmental conditions. I further analyzed the core microbiome to understand stable interannual taxa within each site. I found that Cyanobacteria and Ochrophyta were stable and abundant community members potentially contributing to the year-to-year similarities and environmental correlations. Collectively, the results from Chapter 1 suggest that microbial biofilm diversity may be structured by site specific environmental conditions interannually. I encourage futures studies to continuously monitor diversity through time as alpine streams continue to be impacted by climate change and to more robustly explore the interconnections between streams, hydrology, geochemistry, and microbial ecology.
In my second chapter, I characterized the evolutionary selection pressures and putative adaptations of nitrogenase in cyanobacteria. To do this, I collected biofilms from mountain lakes in the Teton Range and used amplicon based approaches to analyze a fragment of the gene encoding the Fe-protein, nifH, of nitrogenase. Afterwards, I filtered my data to only cyanobacteria and calculated evolutionary selection pressures. I further describe putative biochemical changes in NifH that could signal minor adaptations to the Teton Range. I did this by comparing Teton Range amplicon sequence variants (ASVs) to non-Teton Range sequences from NCBI. The results of this chapter indicate nifH is strongly conserved in cyanobacteria and that there may be biochemical differences in the Fe-protein in the Teton Range for heterocystous and non-heterocystous families of cyanobacteria. Collectively, the results of this chapter reveal the nifH gene is strongly conserved yet there may be minor NifH protein adaptations promoting flexibility across cyanobacterial families. In this chapter, I further suggest consideration of broader sequencing efforts to encompass the full nitrogenase gene complex and to assess non-cyanobacterial diazotroph adaptations.
In the third chapter of my dissertation, I conducted nutrient enrichment experiments in mountain lakes of the Teton Range to investigate how increasing nutrients impact biofilm biomass and community compositions. To do this, I used nutrient diffusing substrates to increase nitrogen (N) and phosphorus (P) concentrations. After the experiment, I quantified photosynthetic and fungal biomass and characterized community composition of cyanobacteria, algae, and fungi with amplicon sequencing. The results of this chapter did not support my expectation of colimitation of N and P in either biomass or community composition. Rather, I observed significant correlations that differed for biomass and the community composition of cyanobacterial, algal, and fungal communities. The results of this chapter highlight that mountain lake photosynthetic and fungal biofilm communities may be limited by other factors such as temperature or micronutrients rather than colimitation. I encourage future studies to assess the interactions between temperature and nutrients on nutrient enrichment biofilm responses.
Together, each chapter of my dissertation helps shed light into the temporal and spatial patterns of diversity, adaptations, and sensitivity of microbial communities to nutrients across alpine streams and mountain lakes of the Teton Range. These results underscore the need to continuously assess microbial diversity across space and time in these habitatsPrice, Taylor. (2025). Microbial diversity across spatial and temporal scales in high mountain watersheds of the Teton Range, U.S.A.. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/275914
Cultivating Leadership Consciousness: A Practical Guide for Next-Generation Nursing Leaders
No full textThis article provides practical tools for cultivating leadership consciousness—the evolving capacity to see self, others, systems, and futures with increasing depth, wisdom, and intentionality. Unlike competency-based training, consciousness development requires sustained inner work, not quick fixes. The framework offered here synthesizes fifty years of nursing leadership scholarship into usable tools for coaching and mentoring the next generation. A coaching guide provides questions to prompt metacognitive reflection on one's leadership consciousness journey.Healthcare complexity demands nursing leaders capable of navigating ambiguity while maintaining caring presence. Yet traditional leadership development emphasizes horizontal skill acquisition—competencies, techniques, tools—while neglecting vertical development: the transformation of how leaders make meaning of themselves, their work, and their impact. This article offers a practical framework for cultivating leadership consciousness through three developmental movements: Recalling (examining formative experiences and unconscious scripts), Reclaiming (integrating strengths while transforming limiting patterns), and Recasting (authoring a conscious legacy). Drawing on the Outcome-Present State-Test (OPT) Model of clinical reasoning, developmental psychology, and foresight leadership, the article provides metacognitive prompts, reflection exercises, and coaching tools specifically designed for nursing students, emerging leaders, and experienced executives. Leadership consciousness develops through sustained inner work, not quick fixes. This guide equips nurse educators, coaches, and mentors with concrete practices to support the next generation's vertical development—cultivating leaders whose consciousness is adequate to healthcare's complexity. In addition, a consciousness development coaching conversation guide is included as a doawn loadable resource.Pesut, Daniel. (2025). Cultivating Leadership Consciousness: A Practical Guide for Next-Generation Nursing Leaders. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276950
Engineering cell-based micropharmacies for in vivo protein replacement therapy
No full textUniversity of Minnesota Ph.D. dissertation. June 2025. Major: Molecular, Cellular, Developmental Biology and Genetics. Advisors: Branden Moriarity, David Largaespada. 1 computer file (PDF); vii, 143 pages.The treatment of many chronic and genetic disorders depends on the consistent delivery of therapeutic proteins to correct underlying deficiencies or modulate disease progression. However, conventional methods, such as enzyme replacement therapy (ERT) and cancer immunotherapies, often require frequent infusions, suffer from limited tissue distribution, or pose a significant burden to patients and caretakers. To overcome these limitations, cell-based micropharmacies have emerged as a promising platform for continuous therapeutic protein expression and targeted delivery in vivo. Utilizing the innate properties of specific cell subsets, such as T cells, B cells, and hematopoietic stem cells, these engineered cells can stably produce and secrete therapeutic proteins. This thesis explores the development of T cell-based micropharmacies for enzyme replacement in Mucopolysaccharidosis type I (MPS I), a lysosomal storage disorder resulting from a deficiency in alpha-L-iduronidase (IDUA). Current treatments, including ERT and hematopoietic stem cell transplantation (HSCT) have improved patient outcomes but they leave significant gaps in addressing manifestations and early mortality. To address these challenges, we engineered primary human T cells to stably express and secrete IDUA. Preclinical studies in an MPS I mouse model demonstrated that engineered T cells are able to secrete functional IDUA and significantly reduce glycosaminoglycan (GAG) accumulation. Furthermore, patient-derived MPS I T cells were engineered to express IDUA, validating the feasibility of autologous cell therapy for personalized treatment.
These findings establish T cell-based micropharmacies as a viable platform for long-term, systemic enzyme delivery, addressing critical limitations of current therapies and setting the stage for broader applications across lysosomal storage disorders (LSDs) and other enzyme-deficiency diseases.Kleinboehl, Evan. (2025). Engineering cell-based micropharmacies for in vivo protein replacement therapy. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276780
"Photon Interaction Frequency Is Essential to Maximize Plasmon-Driven Charge Transfer" - Raman spectra data files and figure data. Collected at the University of Minnesota-Twin Cities Campus between Dec 2024- Jan 2025
No full textData includes 53,321 .csv files and 2 .spe filesThe data includes Raman spectra collected under different excitation conditions (continuous wave and pulsed illumination) for an experimental research study. The data is presented in the paper "Photon Interaction Frequency Is Essential to Maximize Plasmon-Driven Charge Transfer". The upload also includes the data used for the main text figures in the paper. This data was used to draw conclusions about how photon interaction frequency impacts plasmon-driven charge transfer to methyl viologen.We acknowledge support from the MRSEC Program of the National Science Foundation under award DMR-2011401.Koble, MaKenna; Sarkar, Arghya; Frontiera, Renee. (2025). "Photon Interaction Frequency Is Essential to Maximize Plasmon-Driven Charge Transfer" - Raman spectra data files and figure data. Collected at the University of Minnesota-Twin Cities Campus between Dec 2024- Jan 2025. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://hdl.handle.net/11299/276914
Footnotes of a Misaabekong Rugrat
Get PDFUniversity of Minnesota Ph.D. dissertation. 2025. Major: American Studies. Advisor: Jean O'Brien. 1 computer file (PDF); 210 pages.Footnotes of a Misaabekong Rugrat is an artistic exploration of the stories, infrastructures, and navigations of Indigenous communities who collaboratively create and maintain culturally-affirming community networks along the ridgelines of Duluth in the face of colonial legal policies of displacement, erasure, and dispossession aimed to isolate Indigenous peoples from land and each other. Through the blending of poetry, story, artwork, and theoretical exploration, I contextualize the lived and embodied realities of Ojibwe peoples in the hillside within a framework of Anishinaabe stories, spatialities, community structures, and relations. Written from the perspective of a Misaabekong Rugrat — which I define as a kid who learned the world through navigating the stories, built environment, infrastructures, networks, and creative communities of the hillside, usually on foot — Footnotes of a Misaabekong Rugrat is a love letter to the land, plant, animal, spirited, and people communities that have raised me. Chii-miigwech.Walker, Jonnelle. (2025). Footnotes of a Misaabekong Rugrat. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276828
University of Minnesota Presidential AI Task Force Report Administrative Operations Working Group Recommendations
Get PDFAs AI becomes increasingly prevalent, the University must proactively balance its potential for greater efficiency and cost savings with responsible, ethical practices. This requires a structured approach to address legal, compliance, data privacy, and potential impacts on our workforce. To navigate this evolving landscape, the AI Task Force was charged with developing recommendations for AI use in education, research, and operations. Specific charges include benchmarking peer institutions, ensuring compliance with relevant regulations, proposing necessary resources and policy changes, and considering stakeholder well-being, all while upholding academic integrity and ethical standards. This report was developed by the Administrative Operations Working Group to address the adoption of AI for various administrative functions across the University of Minnesota.University of Minnesota. Presidential AI Task Force. AI in Administrative Operations Working Group. (2025). University of Minnesota Presidential AI Task Force Report Administrative Operations Working Group Recommendations. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276900
Create the Future Through Renewal: Twenty Years of Inspiration and Action in Professional Nursing
Get PDFIn November 2003, during the Sigma Theta Tau International biennial convention, I issued a presidential call to action: "Create the Future through Renewal." That call emerged from observing a troubling pattern—nurses increasingly trapped in conversations of regret rather than hope, overwhelmed by complexity, and disconnected from the joy and meaning that originally drew them to the profession. The call invited nurses to reclaim their creative capacities, engage in deliberate self-renewal, and transform professional practice through reflective attention to six essential areas: self, service, scholarship, science, society, and spirit.
Two decades later, that call resonates with even greater urgency. The intervening years have brought unprecedented challenges—pandemic trauma, workforce crises, moral injury, technological disruption, climate change, and widening inequities—all demanding that nurses develop extraordinary capacities for resilience, wisdom, and anticipatory action. What began as an aspirational invitation has become a professional necessity.
This article reflects on twenty years of lived experience with renewal principles, integrates contemporary scholarship, and offers an expanded framework for creating sustainable futures in nursing. It speaks to multiple audiences—individual nurses seeking meaning and resilience, educators shaping the next generation, leaders transforming organizational culture, and professional associations advancing the discipline. The goal is both retrospective wisdom and prospective action: to honor what we have learned while charting pathways forward.Twenty years ago, the call to "Create the Future through Renewal" invited nurses worldwide to embrace creative thinking, reflective practice, and intentional self-renewal as essential elements of professional excellence. This article revisits that foundational call in light of two decades of experience, examining how renewal has evolved from an aspirational concept to an urgent professional imperative. Drawing from contemporary scholarship in reflective practice, moral resilience, workforce well-being, and anticipatory leadership, this article offers both retrospective wisdom and prospective guidance for nursing's next generation. The expanded Renewal Ecosystem framework integrates six interdependent domains—Spirit and Purpose, Self, Scholarship, Service, Systems, and Society—providing nurses with a comprehensive structure for sustainable professional flourishing amid unprecedented complexity. Practical applications demonstrate how renewal principles translate into actionable strategies for individual practitioners, educational programs, healthcare organizations, and professional associations. The article concludes with a renewed call to action, inviting today's nurses to create futures characterized by wisdom, compassion, justice, and hope.Pesut, Daniel. (2025). Create the Future Through Renewal: Twenty Years of Inspiration and Action in Professional Nursing. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277247
Access Across America: Walk 2024
Get PDFAccessibility is the ease of reaching valued destinations. It can be measured for a wide array of transportation modes, to different types of destinations, and at different times of day. There are a variety of ways to define accessibility, but the number of destinations reachable within a given travel time is the most comprehensible and transparent as well as the most directly comparable across cities.
This study estimates the accessibility to jobs by walking or rolling for each of the United States' 8.2 million census blocks and analyzes these data in the 50 largest (by population) metropolitan areas. Travel times by walking or rolling are calculated using detailed pathway networks and low-speed streets. Rankings are determined by a weighted average of job accessibility; a higher weight is given to closer jobs, as jobs closer to origins are more easily reached, and are thus more valuable, than those further away. Jobs reachable within ten minutes are weighted most heavily, and jobs are given decreasing weights as travel time increases up to 60 minutes.
This report presents detailed accessibility values for each metropolitan area, as well as block-level maps which illustrate the spatial patterns of accessibility within each area. Additionally, access to jobs by travel time is separately analyzed according to the income grouping of resident workers who experience that access. Year-over-year changes in accessibility are likewise provided for each area. Given the typically slow change in pedestrian network infrastructure, there are not great changes in walk or roll access. In 2024 improving economic conditions led to higher accessibility, likely a reflection of the land use (job destinations) improvements in walkable areas.Owen, Andrew; Liu, Shirley Shiqin; Lind, Eric M.. (2025). Access Across America: Walk 2024. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277744
Data for 'Hard ferrimagnetism in the layered magnet Li4Mn2Te2O11'
No full textWe report on the characterization of Li4Mn2Te2O11, a previously unstudied layered oxide that exhibits ferrimagnetic ordering below 30 K and an exceptionally large coercive field exceeding 9 T at 2 K. The crystal structure consists of alternating Mn3+ triangular layers and zigzag chains, creating two inequivalent magnetic sublattices. Magnetic measurements reveal net in-plane magnetization and pronounced anisotropy, with strong hysteresis and domain pinning behaviors. The magnetization direction is controlled by the field-cooling history and remains locked under applied fields up to 9 T. Out-of-plane measurements show negligible net magnetization but exhibit a distinct high-field kink, likely attributed to spin reorientation. Heat capacity data show a broad magnetic anomaly that shifts and weakens under field, consistent with antiferromagnetic-dominated interactions. These results establish Li4Mn2Te2O11 as a rare ultrahard ferrimagnet with strong anisotropy, offering a promising platform for low-dimensional spintronic and domain engineering applications.Startup support from the School of Physics and Astronomy at the University of Minnesota, Twin Cities. The work at Princeton was supported by the Gordon and Betty Moore Foundation, Grant No. GBMF-9066. The authors acknowledge the use of the Laue instrument at the Characterization Facility, University of Minnesota.Xu, Xianghan; Cava, Robert. (2025). Data for 'Hard ferrimagnetism in the layered magnet Li4Mn2Te2O11'. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://hdl.handle.net/11299/277154
Quantification of artifacts caused by fixed retainers in dental-dedicated MRI – a descriptive In vitro study
Get PDFUniversity of Minnesota M.S. thesis. June 2025. Major: Dentistry. Advisor: Amy Tasca. 1 computer file (PDF); x, 76 pages.Objectives: Magnetic Resonance Imaging (MRI) is gaining traction in the world of dental imaging and diagnostics. Major strides are being taken to explore low field MRI systems and harness their logistical and clinical advantages over the typical 1.5 Tesla (T) and 3T field strengths. One advantage is reduced susceptibility effects caused by metal dental materials. This study aimed to quantify MRI artifacts produced by a variety of common fixed lingual retainers when scanned in a dental-dedicated MRI (ddMRI) – a low field strength (0.55T) MRI scanner using a dental dedicated extraoral coil. Materials and Methods: Six common orthodontic fixed retainers were scanned in vitro using a 0.55T MRI scanner with the Orthodontic – Anatomy 3D Overview proton density (PD) pulse sequence. The artifact was measured at four different cross-sections: axial, sagittal at the midline, coronal, oblique at the canine and areas (mm2) were calculated. Artifact volumes were superimposed over an average CBCT volume to assess the extent of anatomical structures distorted by each fixed retainer. Results: Stainless steel retainers caused the largest artifacts with .0195 SS Coaxial being the biggest, followed by .030 SS Round, .0215 SS Coaxial, and Ortho Flextech SS respectively. Non stainless steel retainers, .030 Blue Elgiloy and .028 TMA artifacts were significantly smaller. .0195 SS Coaxial, .030 SS Round and .0215 SS Coaxial nearly blocked out the entire anterior oral cavity. .030 Blue Elgiloy and .028 TMA only partially blocked out the mandibular anterior crowns and leave all remaining head and neck structures unaltered. Conclusions: In a ddMRI system, fixed retainer material and style can affect the size of the metal artifacts produced. Retainers without stainless steel prove to be better at reducing artifacts, with .028 TMA being the best followed by .030 Blue Elgiloy. Clinical Relevance: Stainless steel retainers, especially .030 SS Round, and .0195 SS Coaxial and .0215 SS Coaxial will significantly obstruct viewing of adjacent oral structures and could significantly affect the ability to diagnose oral pathology. .028 TMA and Blue Elgiloy are much less likely limit diagnosis in the oral cavity but as with all artifacts, the region of interest dictates if an artifact will have a negative effect. No matter how small an artifact is, if it is present in the target area then it will have a negative impact on diagnosis.Gonyea, Emerson. (2025). Quantification of artifacts caused by fixed retainers in dental-dedicated MRI – a descriptive In vitro study. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276704