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College of Fisheries and Ocean Sciences (CFOS)
The College of Fisheries and Ocean Sciences educates and inspires the next generation of world-class aquatic ecosystem scientists. -
Office of the Provost
The University of Alaska Fairbanks Provost is responsible for providing overall leadership, coordination and direction to UAF research and scholarly activities and graduate studies. -
School of Natural Resources and Agricultural Sciences (SNRAS)
As the primary land-grant component of the university, SNRAS administers a variety of programs and engages in cooperative efforts with federal, state, and borough governments and agencies. -
UAF Graduate School
University of Alaska Fairbanks Graduate School -
Undergraduate Research and Scholarly Activity
At the University of Alaska Fairbanks, the Office of Undergraduate Research and Scholarly Activity (URSA) supports, develops and institutionalizes UAF's diverse and robust programs of undergraduate research and creative ...
Recent Submissions
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Teaching Spanish as a world language in Waldorf schools for grades one to eightWaldorf education provides a unique opportunity for students to fully experience their lessons in an integrative, artistic, and purposeful way, and this is certainly true for world language classes. Throughout a typical curriculum, various art forms are utilized along with physical movements and actions, allowing students to live through the lessons in an interesting and enjoyable way. At times, it becomes difficult to separate between songs, poems, skits, gestures, plays, or games, when all of these methods can be interwoven simultaneously. By integrating rhyme, repetition, gestures, music, movement, and visuals, classes become quite lively and interactive. It takes a lot of planning and preparation to teach this way, and Waldorf teachers typically juxtapose songs, poems, skits, plays, games, and activities that reinforce important topics, vocabulary, and themes throughout the year. In addition to memorizing material and delivering enthusiastic, heartfelt, and artistic lessons from memory, the teacher must gather all the various resources for a topic and decide on the best way to present them to the class. This project offers many of those connections for Spanish language lessons in a Waldorf setting, and it can also be altered and adapted for other world languages. Much of the foundational theory is common across different world languages, but it is helpful to find enough authentic and original material in the target language that has not been translated. Specific examples are given for Spanish language classes, as well as many commonly known stories that can be delivered in any language. Goals, activities, topics, skills, and milestones are suggested for each grade. This project provides the world language teacher with a solid outline or template for creating lessons in each grade, with enough material and references to start right away.
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Factors affecting nest and brood survival of rock ptarmigan (Lagopus muta) in Interior AlaskaRock ptarmigan (Lagopus muta) are a circumpolar species endemic to high elevations and latitudes of North America and are common throughout Alaska. The r- selected life history of ptarmigan indicates that reproduction and specifically nest and brood survival is the most important component of population growth. However, factors affecting these population parameters have not been studied extensively or intensively, since there have only been three studies done in Alaska. Rock ptarmigan exhibit population fluctuations, which may be caused by changes in reproduction and survival due to predation and weather events. Warming climatic patterns and shifts in the range of their food resources may also be impacting rock ptarmigan populations. Previous research on rock ptarmigan in Alaska was completed five decades ago and methods of assessing their populations have improved. Therefore, a better understanding of factors affecting nest and brood survival is essential for understanding factors limiting population growth, particularly in a rapidly changing environment. In this study, we investigated whether variations in hen age, weather, timing of nest initiation, and nesting habitat affected nest and brood survival across two study sites. We focused this study on previously studied alpine populations of rock ptarmigan at Eagle Summit and Denali Highway sites in Interior Alaska from spring through summer in 2018 and 2019. Hens outfitted with transmitters were monitored weekly to determine the status of their nest or brood. We found canopy cover around the nest had the most effect on nest survival. Survival of nests with a closed canopy was more than five times higher than those with an open canopy at the Eagle Summit site and nearly two times higher at the Denali Highway site. Ptarmigan at Eagle Summit had higher brood survival than ptarmigan at the Denali Highway site. Our modeling indicated that survival of nests and broods was not affected by fluctuations in seasonal weather (e.g., minimum temperature and maximum precipitation). Establishing a basis for understanding temporal and spatial trends in population ecology is essential for effective management in a rapidly changing environment and these findings may improve the management of rock ptarmigan.
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Toward multidisciplinary volcanic eruption models and forecasts in Alaska: contributions from automated seismic and acoustic signal detectionExplosive, ash-generating volcanic eruptions pose an increasing threat to a growing, globally connected population. Accurate forecasts of volcanic eruptions remain challenging due to the complexity of volcanic systems, but recent multidisciplinary synthesis efforts have proven effective. The National Science Foundation Prediction of and Resilience against Extreme Events (PREEVENTS) project aims to re-analyze and combine multidisciplinary observations at eight Alaska volcanoes to develop eruption forecast models. Leading the seismology and infrasound discipline, this dissertation details the development of automated tools capable of producing high-resolution catalogs of volcanic unrest signals from continuous seismic and acoustic data. By leveraging these catalogs and synthesizing insights from other disciplines, we re-examine past eruptions at select Alaska volcanoes and investigate their underlying mechanisms. Chapter 1 provides an overview of volcano monitoring in Alaska, and how different disciplinary insights converge to help us infer pre-, syn- and inter-eruptive processes. Chapter 2 presents an integrated workflow for improving volcanic earthquake catalogs. Using a combination of standard triggering, cross-correlation clustering, matched- filtering, and earthquake relocation methods, we recover previously undocumented seismic activity and refine interpretations of seismogenic zones at Redoubt and Augustine volcanoes. Chapter 3 introduces the Volcano Infrasound and Seismic Spectrogram Neural Network (VOISS-Net), a machine learning method for detecting and characterizing volcanic tremor and other transient signals. VOISS-Net provides a rapid and consistent means of classifying data in near real time and summarizing long-term data. Trained and applied on Pavlof Volcano, VOISS-Net reveals vent-specific seismic tremor profiles. Chapter 4 builds upon this idea of vent-specific unrest, integrating geodetic, petrologic, gas and thermal remote sensing data. We find that the summit and southeast flank vents at Pavlof Volcano exhibit contrasting eruption dynamics, which we attribute to differences in volatile content, magmatic ascent rate, and conduit geometry. Lastly, Chapter 5 concludes with a discussion of other relevant work and future research directions.
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Optimal control and inverse problems for partial differential equations and variational inequalitiesThis dissertation addresses optimal control problems for nonlinear evolutionary variational inequalities involving Volterra-type operators and inverse problems for the Dirac system on finite metric graphs. The first part presents the historical background, novelty, and motivation behind the research studies. In the second part, we focus on solving the initial value problem for nonlinear evolutionary variational inequalities with Volterra-type operators, proving the existence of a unique solution using the Banach fixed-point theorem. The third part explores an optimal control problem for these inequalities, establishing the existence of a solution under specific assumptions on the given data. In the last part of the dissertation, we examine the inverse dynamic problem for the Dirac system on finite metric tree graphs, as well as a graph with a single cycle (a ring with two attached edges). First, we solve the forward problem for this system on general graphs using a novel dynamic algorithm and then address the inverse problem for the same system on finite metric tree graphs. We recover unknown data such as the topology (connectivity) of a tree, edge lengths, and matrix potential functions associated with each edge. This is achieved using the dynamic response operator as the inverse data and the leaf peeling method. We also determine the minimum time required to uniquely identify the unknown data. Finally, we demonstrate the solution to the inverse problem for the Dirac system on a ring with two attached edges, establishing the minimum time needed to uniquely determine the unknown parameters for this graph.
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Ligand substitution versus DNA-binding affinity : ǂb syntheses, structures, and in vitro anticancer activities of Pt(CH₃)₂I₂{2,2'-bipy-n,n'-(CH₃)₂} (n,n' = 4,4'; 5,5'; 6,6')In chemotherapeutic treatment for leukemia, the drug cisplatin is highly effective. However, there is an immense need for cisplatin analogues that are more clinically viable. Cancer cell assay studies have shown that the platinum(IV) complex Pt(CH₃)₂I₂{2,2'-bipyridine} exhibits significant anticancer activity against the human breast cancer cell line ZR-75-1, with an EC50 (effective concentration 50%) concentration of 6.1 μM— substantially lower than that of cisplatin (16.4 μM). To explore the unknown structure-activity relationship between DNA binding and anti-cancer activity, three isomers — Pt(CH₃)₂I₂{2,2'-bipy-n,n'-(CH₃)₂} where n,n’ = 4,4’; 5,5’; 6,6’— were synthesized. The intent was to demonstrate decreased cytotoxicity as complex-DNA steric hindrance increased through the positioning of the methyl groups on the bipyridine ring of the isomers. All isomers were structurally characterized via single-crystal X-ray diffraction, nuclear magnetic resonance (NMR), and infrared spectroscopy (IR). Their cytotoxic profiles were evaluated through the National Cancer Institute’s Sulforhodamine B screening assay. Among them, Pt(CH₃)₂I₂{2,2'-bipy-6,6'-(CH₃)₂} demonstrated the most potent activity with a notable LC50 (lethal concentration 50% ) value of 7.34 μM against ovarian cancer (OVCAR-3). DNA- binding studies using UV-Vis absorption spectroscopy revealed intrinsic binding constants (Kb) of 1.74×10⁴ M⁻¹ and 3.74×10⁴ M⁻¹ for the 6,6'-dimethyl and unsubstituted bipyridine complexes, respectively. A competitive displacement reaction monitored by 'H NMR showed that Pt(CH₃)₂I₂{2,2'-bipy-6,6'-(CH₃)₂} reacts completely with free 2,2’-bipyridine to yield Pt(CH₃)₂I₂{2,2'-bipyridine} and liberated 6,6’-dimethyl bipyridine. These findings suggest that DNA-binding affinity does not directly correlate with cytotoxic potential and that steric factors introduced by ligand substitution play a more critical role in determining anticancer efficacy in these bipyridine-stabilized platinum(IV) compounds.
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Strontium isotope movement modeling of modern and ancient megafauna in AlaskaStrontium isotope analysis is a technique that can be used to infer the geographic origin of biological materials. The strontium isotope ratios (87Sr/86Sr) of biological tissues can be matched to locations on a modeled strontium geographic distribution (“isoscape”) with similar 87Sr/86Sr. In this dissertation, I measured 87Sr/86Sr and other stable isotopes along the length of a mammoth tusk to model its lifetime movement and infer details about its food sources and nutritional status. I then adapted this modeling method to caribou tooth enamel to compare modern and premodern caribou space use in interior Alaska and built a new 87Sr/86Sr isoscape of interior Alaska and western Yukon with 87Sr/86Sr data from analyses of small rodent teeth. Finally, I added vegetation measurements to the isoscape model in northern Alaska, showing that vascular and non-vascular plants do not differ in 87Sr/86Sr in this region, and argued that further improvement of the isoscape of the region is necessary. Overall, the research completed in this dissertation expanded on the use of 87Sr/86Sr in reconstructing the movement of large mammals, and improved the potential for this proxy to be used in broader provenance and mobility studies in Alaska.
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Perspectives on Northern Gulf of Alaska freshwater pathways, wind, and linkages to phytoplankton biomassThe biologically productive northern Gulf of Alaska continental shelf receives freshwater from surrounding watersheds and wind stress from atmospheric pressure systems. A better characterization of the relationship between wind and salinity spatiotemporal variability is important for understanding the fate of freshwater and its ecological importance. In Chapter 2, I analyzed 25 years of northern Gulf of Alaska hydrographic data to reveal mid-shelf and shelf break freshwater pathways that impact stratification, currents, and freshwater distribution. Process studies of the Copper River plume’s propagation towards the shelf-break and beyond inform ecological function on the northern Gulf of Alaska shelf and productivity in the high- nutrient, low-chlorophyll waters of the adjacent slope and basin. Horizontal density fronts are often sites of locally enhanced ecological activity and accumulated biomass that contribute to biological patchiness on continental shelves. In Chapter 3, I analyze a high-resolution hydrographic dataset spanning spring, summer, and fall to identify wind-driven symmetric instabilities in the upper water column, improving our understanding of northern Gulf of Alaska submesoscale dynamics, its seasonality, and its role in driving phytoplankton patchiness. Autonomous underwater glider observations can improve our understanding of environmental forcings influencing spring bloom timing. In Chapter 4, I analyzed four environmental parameters: the potential energy anomaly, the mixed layer depth, light, and chlorophyll-a concentrations, assessed in relation to the stabilizing and destabilizing effects of wind, surface buoyancy flux, and tides. Bloom onsets coincided with high irradiance throughout the mixed layer, reduced wind stress and, over the mid-shelf, shoaling of the mixed layer above the euphotic zone driven by stratification, while in a coastal embayment, stratification had less influence on bloom onset. Primary productivity was estimated using a bio-optical model. These results clarify how interacting physical processes shape production in the northern Gulf of Alaska, improving our ability to anticipate ecosystem responses to climate change.
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The transformational learning by web-conferencing circuit board: a conceptual model outlining the conditions that facilitate transformation in synchronous spacesAs synchronous technologies and high-speed internet have become more accessible, opportunities for learning in web-conferencing settings have also increased. Despite the ubiquity of learning experiences taking place over web-conferencing, there is a lack of research on what makes for effective adult learning in synchronous settings from learners’ perspectives. Moreover, there are few studies examining how transformational learning—learning that changes an adult’s mindset, beliefs, or perceptions—occurs in web-conferencing settings. This qualitative study explores the conditions through which transformational learning occurs in web-conferencing settings. It includes the perspectives of adult learners (all at least eighteen years old) who have participated in a variety of learning experiences via web-conferencing. I completed this study in two phases: (1) qualitative surveys collected from ten anonymous participants, and (2) semi structured interviews conducted with eleven participants. I employed grounded theory methods to develop the Transformational Learning by Web-Conferencing Circuit Board, a conceptual model that describes the conditions enabling transformational learning to occur in synchronous settings. This conceptual model illustrates that organizations, facilitators, and adult learners play distinct roles in supporting transformational learning through web-conferences. The conceptual model also describes how goal orientation, mindsets and beliefs, technological efficacy, and conducive virtual and physical environments support the sense of community among adult learners and facilitators in the web-conferencing space. When learners and facilitators feel this sense of community, transformational learning is possible. Organizations, facilitators, and adult learners interested in participating in a transformational learning experience within a web conferencing setting can utilize this conceptual model to inform their engagement in the process. Researchers may also build upon the framework to further our collective understanding of how transformational learning occurs in synchronous learning environments.
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Dynamic Pairwise Sparse Tuning (DPST) vs. Static two-predictor selection: a neural network approachIdentifying two active predictors driving a response variable is critical in fields like genomics, medicine, and finance, yet standard methods, such as penalized regression, often fail to isolate these pairs consistently. We propose Dynamic Pairwise Sparse Tuning (DPST), a novel feedforward neural network (FNN) method that enhances sparse predictor selection by augmenting standard backpropagation with custom weight updates using adaptive thresholding, smoothed refinement, and pruning. Through simulations across predictor counts (P = 3, 4, 5) and sample sizes (N = 1800, 3600) using a controlled sparse coefficient matrix defining pair relationships, DPST consistently outperforms our static FNN baseline, also developed by us, which uses only backpropagation. For instance, DPST achieves an accuracy of 0.732 versus 0.609 at P = 5, N = 3600, across C = (P) pairs (3, 6, 10). The baseline excels at P = 3, N = 3600 (accuracy 0.960 vs. 0.684), where DPST’s updates limit generalization, and trains faster (e.g., 3.57 s vs. 20.66 s). DPST’s precision suits applications like gene-pair detection and financial risk modeling, while the static baseline supports rapid analyses. Our results highlight DPST’s potential to advance sparse modeling.
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Molecular survey of Leptospira spp. and Bartonella spp. in Alaskan volesLeptospira spp. and Bartonella spp. are two Gram-negative bacterial genera responsible for important zoonotic diseases worldwide, yet they remain poorly studied in northern ecosystems. Out objective was to assess Bartonella and Leptospira prevalence in vole populations in Interior Alaska and examine potential associations between prevalence and human activities (landscape and resource modification from sled dog kennels and reindeer farms). I surveyed for Bartonella and Leptospira in three vole species, Clethrionomys rutilis, Microtus pennsylvanicus, and Alexandronomys oeconomus, collected from three different areas in Interior Alaska in the summer of 2024. Using conventional PCR, I targeted the 16S rRNA gene for Leptospira spp. and the 16S-23S internal transcribed spacer (ITS) region for Bartonella spp. While no voles were found positive for Leptospira, Bartonella DNA was detected in 38 of 229 voles. Five species of Bartonella were identified: B. henselae, B. grahamii, B. doshiae, B. rochalimae, and B. heixiaziensis. This is the first study to identify B. grahamii, B. doshiae, B. rochalimae, B. henselae, and B. heixiaziensis in Alaska, and the third to identify Bartonella in Alaskan voles. Bartonella prevalence varied significantly across all three areas, with an areawide prevalence of 16.5%. While Bartonella prevalence varied significantly on a geographical scale, anthropogenic disturbance was not found to be correlated with prevalence. These findings suggest that ecological and population-level factors may play an influential role in the transmission dynamics of Bartonella in small mammal populations. This study contributes to the understanding of bacterial pathogens in northern small mammal populations.
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Data Submission Package for MS Svalvard LEX Surveys with ML/AI analysis (pending review)This dataset consists of the Appendices used for the analysis of Svalbard data seabirds and marine mammals.
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Alaska Village Roads Guide: Suggested Roadway Geometrics and Design Considerations for Alaska Village Roads with Mixed UseThe ultra-low-volume roads guide is designed to provide guidance for the construction of roadways in rural, isolated, Indigenous, or tribal areas with less than 100 average daily trips (<100 ADT). These roads serve a unique purpose in their communities and warrant special considerations in their design. This guide enumerates design guidelines and considerations to help designers match roadway function and design while maximizing safety, economic efficiency, and suitability for community needs.
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Why do people move?: An upper elementary oral history unit on the history of migration in AlaskaIt has become apparent that social studies is largely absent as a topic of study in our nation's elementary schools. This is a great disservice to our children and their ability to become productive and caring global citizens. This paper outlines the process of creating a manageable and engaging social studies unit for upper elementary classrooms. The curriculum that was created focuses on the history of migration in the state of Alaska with an emphasis on primary sources from the Kenai Peninsula. The curriculum requires two lessons per week for the duration of a quarter. Lesson plans are clearly outlined with step-by-step instructions and links to necessary resources. Students are asked to closely listen to, observe, and read primary sources and make factual statements based on their observations. The second half of the curriculum focuses on the process of conducting professional oral history interviews as students interview a member of the community. The final culminating project is to introduce the person interviewed in a community celebration with a high-quality poster and presentation.
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Data for Manuscript (MS; in review) Common Leopard and Snow Leopard Overlap Models in Central Himalaya, NepalData used for a manuscript (MS) on Common Leopard and Snow Leopard habitat overlap models in the Central Himalayas during the Anthropocene.
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The WNBA and activism: a case study of Power of the DreamThis thesis looks at how WNBA players used their platform to stand up for social and political change during the 2020-2021 season. This research focuses on the documentary Power of the Dream (Porter, 2024), which follows the Atlanta Dream and other WNBA players during a time of a global pandemic, racial injustice, and an election year. Guided by public relations scholars Bernays (1961), Curtain and Gaither (2007), Ciszek (2015) for my methodology. By using the Cultural-Economic Model (CEM) (Ciszek, 2015) and understanding their five interconnected components to guide understanding of activism in sports. By using thematic analysis (Braun & Clarke, 2006), this research found five key themes in the film: power in unity, bigger than basketball, symbolism and strategic communication, intergenerational leadership and emotional labor, and political impact. The WNBA players did more than play basketball, they used their voices and actions to create change. They wore t-shirts with powerful messages, sat out games to protest injustice, and supported political candidates. Their teamwork and leadership helped make a real difference, including helping elect Georgia’s first Black senator. This study shows how athletes can be powerful leaders off the court. It also highlights the emotional strength and care that went into their work on and off the court. The WNBA’s activism reminds us that sports are not isolated from the real world, they are part of it, and athletes have the power to shape it.
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Modeling the effects of socioeconomic and environmental factors on child malnutrition and contamination risk using generalized estimating equationsMalnutrition and environmental contamination remain critical public health problems among children under five years old, particularly in developing environments. This paper investigates the sociodemographic, environmental, and behavioral factors that influence the risk of contamination and child malnutrition using Generalized Estimating Equations (GEE) in order to adjust correlations across repeated observations. Two multivariate binary response variables were taken into consideration: SWUbinary comprised of three binary indicators of whether the child was stunted, wasted, or underweight; and RTbinary comprised of two binary indicators of contamination exposure based on the presence of Relative Light Unit (RLU) and Total Coliform Analysis (TCA) contamination in a household. Using Point-Biserial Correlation and Cramer’s V Statistic, relevant predictor variables were screened and backward stepwise selection was used to determine the best set of predictors from those remaining for each of three correlation structures: unstructured, exchangeable and independent. The best model for each of the two response variables was chosen using the Akaike Information Criterion (AIC). For SWUbinary, the exchangeable correlation model was selected, and for RTbinary, the independent correlation model was the selected model. The results show how important it is to look at both nutrition and environmental factors together when trying to improve the health and well-being of children.
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Dissolved and particulate nutrient dynamics in the Northern Gulf of Alaska: a productive subarctic shelf ecosystemThe Northern Gulf of Alaska (NGA) is a biologically productive system, culturally and economically sustaining Alaska’s coastal communities, with inorganic nutrients as an important foundation of this important food web. Nonetheless, seasonal cycles, interannual variability, and nutrient chemistry all influence nutrient dynamics, creating challenges in the overall understanding of the NGA ecosystem and the resources it provides. Therefore, this work examines nutrient sources, sinks, and trends over time and location to identify and explain key nutrient dynamics within the NGA. One key process is the exchange between dissolved (potentially bioavailable) and particulate nutrients that is examined in Chapters Two and Three. In Chapter Two, the seasonal and interannual cycles of dissolved nutrients are examined, and in Chapter Three, the sources, transport, and role of particles as nutrient reservoirs are considered. Finally, in Chapter Four, the Copper River, a major source of both dissolved and particulate nutrients to the nearshore NGA, and its associated freshwater plume are discussed with respect to the transport of resources under variable wind conditions.
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Exploring the intersection of race and native speakerism in English language teaching: experiences of Black African teachers in TurkeyResearch on race and native speaker status in language teaching provides little insight into the experiences of Black African English teachers (BAETs) in the diaspora. To address this gap, this study examines how aspects of BAETs' positionalities - such as race and native speaker status create challenges in their professional and societal lives in Turkey. Data from twelve semi structured interviews of BAETs were analyzed using thematic analysis. Findings suggest that race related challenges trump language-related ones and that Blackness fundamentally shapes outsiders’ perception and value of BAETs’ linguistic expertise. Even when BAETs possess the same or superior qualifications as their White colleagues, they endure additional hardships due to their race (e.g., racial slurs, lower wages). Drawing on Foucault and Bourdieu’s theories of power and capital, along with Flores and Rosa’s concept of raciolinguistic ideologies, this study enhances our understanding of how racial hierarchies of power and capital systematically devalue BAETs' linguistic expertise and professional worth.
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Measuring Arctic ground squirrel adult neurogenesis in caudal hippocampus using DAB/DAB-Ni enzyme-based immunohistochemistryUnconscious patients who are resuscitated after cardiac arrest often have a poor prognosis for neurological recovery and are routinely treated with therapeutic hypothermia as a standard of care. This intervention aims to reduce the risk of death and minimize brain damage. However, results from the Targeted Temperature Management 2 (TTM2) trial in 2021 indicate that cooling does not improve neurological outcomes in these patients. This finding raises questions about the neurological benefits, particularly regarding neurogenesis, of the rewarming phase of therapeutic hypothermia, as well as the effects of repeated cooling and rewarming cycles. Neurogenesis has been largely overlooked in therapeutic hypothermia research, leaving significant gaps in our understanding. Notably, hibernation and therapeutic hypothermia share physiological similarities, but hibernation is a more complex process that confers neurological protection against cardiac arrest in the Arctic ground squirrel (AGS), an extreme hibernator. Specifically, during hibernation, AGS repeatedly lower body temperature to as low as 1 to -3°C, along with reduced blood flow and metabolism during torpor, then periodically rewarm to normal levels during brief interbout arousals. These repeated cooling and rewarming cycles happened at least eight times during hibernation. Building on this knowledge, this thesis explores the possibility that cooling and rewarming could activate neurogenesis and thereby improve the benefits of therapeutic hypothermia by replacing dead and damaged neurons. As proof of concept, I developed a method for measuring hippocampal neurogenesis in the AGS across three seasonal states: summer active, hibernation torpor, and interbout arousal.
