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When society is not safe: impact of chronic minority stress on threat responsivity and threat-related decision making in the LGBTQIA+ community
No full textUniversity of Minnesota Ph.D. dissertation. 2025. Major: Psychology. Advisors: Robert Krueger, Katerina Marcoulides. 1 computer file (PDF); iv, 462 pages.Members of the LGBTQIA+ community experience disproportionate rates of mental healthconcerns, such as anxiety disorders, PTSD, and depression, while also being at heightened risk of
stigma, rejection, and violence. Under the minority stress model, societally-imposed stressors,
such as stigma, discrimination, and hate-motivated violence, as well and internalized responses
to those stressors, increase risk of physical and mental health concerns for members of the
LGBTQIA+ community. A number of minority stressors, including hate-motivated violence,
lack of social support, and heightened vigilance for threat due to occupying a marginalized
identity, have strong theoretical overlap with basic threat learning and threat responding
processes. However, to-date, no published research studies have leveraged fear conditioning or
threat responsivity measurement tools to better understand basic changes to threat learning and
responding that minority stress experiences may prompt. This dissertation examines the impact
of minority stress experiences on several threat learning and threat responding outcomes, in a
group of LGBTQIA+ participants. Findings and their implications are discussed.Manbeck, Adrienne. (2025). When society is not safe: impact of chronic minority stress on threat responsivity and threat-related decision making in the LGBTQIA+ community. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278040
Dead or alive: fungal controls on decomposition and soil carbon storage in Northern temperate forests
No full textUniversity of Minnesota Ph.D. dissertation. 2025. Major: Ecology, Evolution and Behavior. Advisors: Sarah Hobbie, Peter Kennedy. 1 computer file (PDF); viii, 131 pages.Soils store more carbon (C) than living vegetation and the atmosphere combined. Therefore, understanding the factors that regulate soil C storage and loss (decomposition) will be critical in understanding C cycling under ongoing climate change. Fungi play key roles in decomposition and C storage in forests by being the primary decomposers (saprotrophs) and acting as plant mutualists (ectomycorrhizal fungi; ECM). It has been hypothesized that these ECM fungi, which receive C from their host plant, can outcompete saprotrophs for nitrogen (N), reducing decomposition. However, it is unclear a) whether this suppressive effect of ECM fungi on decomposition leads to increased C storage and b) how widespread it is among temperate pine forests. Further, recent research has found a majority of soil C and N is made up of dead fungal hyphae (necromass), yet the chemical controls on C and N loss from necromass during decomposition and how these interact with global change factors like N addition, are poorly understood. The goals of this dissertation are therefore to elucidate the consequences and variation of ECM-saprotroph interactions and to clarify how N fertilization impacts fungal necromass decomposition. In chapter 1 I found that the presence of ECM fungi decreased the decomposition of belowground tissues and increased soil C stocks by 10%. This latter effect was strongest in the top 5 cm of soil and in fast-cycling, unprotected soil C. In chapter 2 I found that ECM suppression of leaf litter decomposition is not as widespread across temperate pine forests as previously theorized. Rather, ECM fungi either increase or do not affect pine litter decomposition in pine forests in California, Minnesota, and Florida. In chapter 3 I found that necromass C loss, N loss, and responses to fertilization varied with necromass chemistry. Specifically, N addition inhibited late stage necromass decomposition, but this effect was weakest in melanin-rich necromass, contrary to hypotheses based on plant litter. Together, these results add to our understanding of how fungi, dead and alive, influence soil C and N cycling and highlight the diversity and importance of fungal chemistry and interguild interactions.DeLancey, Lang. (2025). Dead or alive: fungal controls on decomposition and soil carbon storage in Northern temperate forests. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278152
The local economic impacts of Amazon: evidence from fulfillment centers and lessons for local economic development
No full textUniversity of Minnesota Ph.D. dissertation. July 2025. Major: Economics. Advisor: Jeremy Lise. 1 computer file (PDF); iii, 120 pages.Does the entry of a large employer to a local labor market increase welfare for residents? What are the implications for local economic development policy? To answer these questions, this dissertation conducts the first, comprehensive analysis of the dramatic expansion of Amazon’s fulfillment center (FC) network from 2010 onward. In Chapter 1, I exploit the staggered roll-out of FCs across large U.S. metros in a difference-in-difference framework. I find Amazon’s entry to a new metro increases the total employment rate by 1.0 percentage points and average wages by 0.7 percent. The industrial composition of employment shifts from retail and wholesale trade to warehousing and tradeable services, primarily driven by younger workers. Employment gains are concentrated among non-college workers. Local rents increase by 1.1 percent, utility costs by 6.0 percent, and home values by 5.6 percent. In Chapter 2, I present a detailed spatial equilibrium model of the U.S. economy. My model is an extension of the classic urban economics models of Rosen (1979) and Roback (1982), combined with elements of modern quantitative spatial equilibrium models, such as Kline and Moretti (2014) and Redding and Rossi-Hansberg (2017). It incorporates worker heterogeneity in education and home ownership, productivity spillovers across sectors, local government-financed public goods, and unobserved non-wage amenities. The model yields welfare expressions that transparently map the impact of eight distinct channels, all of which have been shown to be empirically important for the welfare incidence of local labor demand shocks. These channels include (1) direct employment effects, (2) cross-sector spillovers, (3) local cost of living, (4) average home values, (5) local public goods, (6) corporate subsidies, (7) non-wage amenities, and (8) migration. In the third and final chapter, I calibrate my spatial equilibrium model to the U.S. economy before and after Amazon’s expansion. I estimate welfare effects in the aggregate and by education and home ownership status. I find a net increase in welfare: the average worker is willing to pay $329 per year (0.8 percent of income) to live in a large U.S. city after Amazon’s entry. The welfare gains are primarily driven by rising home values; the increase in employment, wages, and sectoral shifts are partially offset by rising local costs of living and a declining average value of non-wage amenities in large cities. Corporate subsidies have a negligible impact on welfare as they are a small share of state and local budgets. I conclude with recommendations for state and local leaders when evaluating local economic development policies.Cunningham, Evan. (2025). The local economic impacts of Amazon: evidence from fulfillment centers and lessons for local economic development. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278150
The epigenetic role of Lysine Specific Demethylase 1 in Osteoclast Differentiation
No full textUniversity of Minnesota Ph.D. dissertation. January 2025. Major: Oral Biology. Advisor: Kim Mansky. 1 computer file (PDF); vii, 134 pagesOsteoclasts are large multinucleated cells that degrade bone mineral and extracellular matrix. Investigating the mechanisms by which osteoclast differentiation is epigenetically regulated is a key to understanding the pathogenesis of skeletal related diseases such as periodontitis and osteoporosis. Lysine specific demethylase 1 (LSD1/KDM1A) is a member of the histone demethylase family that regulates gene expression via the removal of mono- and dimethyl groups from H3K4 and H3K9. Prior to this study, little was known about the effect of LSD1 on skeletal development and osteoclast differentiation. Here, we show conditional deletion of LSD1 in both myeloid and monocyte lineages results in a decrease in osteoclast differentiation and activity. Furthermore, LSD1LysM-cKO females, but not males, have increased bone mass. Contrarily, LSD1Cfms-cKO males, but not females, have increased bone mass. We further demonstrate that LSD1 can form a complex with CoREST, HDAC1 and HDAC2 suggesting a mechanism by which the combination of methylation and acetylation of histone residues regulates osteoclast gene expression. Lastly, we demonstrate that LSD1LysM-cKO male and female mice are resistant to periodontitis induced bone loss, suggesting that even in inflammatory conditions, LSD1 is important in driving osteoclast differentiation.Astleford-Hopper, Kristina. (2025). The epigenetic role of Lysine Specific Demethylase 1 in Osteoclast Differentiation. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278799
Minutes: Civil Service Consultative Committee: December 11, 2025
No full textIn these minutes: P&A Update; Reports to Civil Service Consultative Committee; Office of Human Resources Update; CS Special Election; Professional Development, Communication DiscussionUniversity of Minnesota: Civil Service Consultative Committee. (2025). Minutes: Civil Service Consultative Committee: December 11, 2025. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278936
The Bark (2025-11)
No full textUniversity of Minnesota Duluth. (2025). The Bark (2025-11). Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278826
Exploring amino acid-based electrolytes for enhanced carbon dioxide electroreduction efficiency using a copper oxide catalyst
No full textUniversity of Minnesota M.S.Ch.E. thesis. July 2025. Major: Chemical Engineering. Advisor: Sam Toan. 1 computer file (PDF); 1 viii, 105 pages.This study investigates the CO2 electroreduction ( CO2ER) using a Copper / Copper (I) Oxide (Cu/Cu2 O) catalyst adapted from a previous study, focusing on the impact of electrolyte composition on product selectivity and efficiency. The catalyst, featuring a porous aerogel network with Cu^0/Cu^+ interfaces, promotes carbon-carbon (C-C) coupling and ethanol synthesis with high current density. Potassium chloride, used in the original study as a non-buffering reference electrolyte, was reproduced in our experiment to serve as a benchmark. It maintains a high local pH, which enhances *CO intermediate accumulation, yielding formate and ethanol with faradaic efficiency (FE) of ~6% and ~0.44% at -1.7V vs. Ag/AgCl, respectively. FE for ethanol and formate was determined via nuclear magnetic resonance (NMR) spectroscopy. Amino acid electrolytes (arginine, histidine, glycinate, L-lysine hydrate) were tested at an adjusted applied voltage of -1.3V vs. Ag/AgCl to account for lower conductivity. NMR analysis revealed electrolyte-dependent chemical shift variations, with histidine showing the highest formate FE (0.67%), followed by arginine (0.35%) and glycinate (0.12%). L-lysine hydrate uniquely produced acetate, likely due to high local pH promoting *CO retention and C-C coupling. However, overestimated FE (>100%) suggests NMR integration errors due to peak broadening. These findings underscore the influence of electrolyte hydration, pH, and composition on CO_2 ER selectivity, with NMR offering a valuable, though pH -sensitive, method for CO2 reduction products quantification.Habib, Hafsa. (2025). Exploring amino acid-based electrolytes for enhanced carbon dioxide electroreduction efficiency using a copper oxide catalyst. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277970
2024-2025 UMRA Book Club I Annual Report
No full text. (2025). 2024-2025 UMRA Book Club I Annual Report. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278594
Selberg zeta functions and Wilson Spools in 3D Chern–Simons quantum gravity
No full textUniversity of Minnesota M.S. thesis.July 2025. Major: Physics. Advisor: Claire Zukowski. 1 computer file (PDF); iii, 43 pages.In quantum gravity, the Euclidean path integral encodes the full quantum dynamics of bothfields and background geometry. In general, it cannot be evaluated exactly and thus requires expansion around classical saddle-point solutions. We focus on the one-loop determinant, which captures these leading quantum corrections through the functional determinant of the kinetic operator governing the theory. In the context of 3D gravity, we study these functional determinants using two distinct methods: the Selberg zeta function and the Wilson spool. The Selberg zeta function, a generalization of the Riemann zeta function in terms of the lengths of closed geodesics on hyperbolic quotient geometries, provides a simple method for computing functional determinants. It has since been applied in quantum gravity to study the functional determinant of the Euclidean BTZ black hole, a three-dimensional hyperbolic quotient. The Wilson spool, arising from the Chern–Simons formulation of three-dimensional gravity, is of particular interest because it couples matter to quantum gravity and incorporates off-shell fluctuations, unlike standard saddle-point methods. We begin by establishing a formal connection between the two objects in the context of the BTZ black hole. We then turn to Euclidean de Sitter space, where we show that, despite the absence of a Selberg zeta function, one can construct an associated trace formula. We show that, with an appropriate choice of test function, the trace formula gives rise to the Wilson spool. Finally, we comment on how this procedure can be extended to construct Wilson spool candidates for more general spaces, such as lens spaces and higher-dimensional spheres.Haupfear, Samuel. (2025). Selberg zeta functions and Wilson Spools in 3D Chern–Simons quantum gravity. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277972
The Bark (2025-04)
No full textUniversity of Minnesota Duluth. (2025). The Bark (2025-04). Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278823