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Episode 191: 'The Big One' with Mark Olshaker, Ann Hennigan Grace, & Dr. Sydney Redepenning
No full textRuntime 01:10:41In this week's special episode, Chris Dall interviews Dr. Osterholm and his coauthor Mark Olshaker on their new book “The Big One: How We Must Prepare for Future Deadly Pandemics”. They are also joined by Ann Hennigan Grace and CIDRAP's Dr. Sydney Redepenning who both conducted research and fact-checking for the book.Dall, Chris; Osterholm, Michael; Olshaker, Mark; Hennigan Grace, Ann; Redepenning, Sydney. (2025). Episode 191: 'The Big One' with Mark Olshaker, Ann Hennigan Grace, & Dr. Sydney Redepenning. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278877
Induced representations for finite groups of Lie type as Hecke algebra modules
No full textUniversity of Minnesota Ph.D. dissertation. July 2025. Major: Mathematics. Advisors: Benjamin Brubaker, Paul Garrett. 1 computer file (PDF); iii, 112 pages.Let G be a split, connected reductive algebraic group taken over some p-adic field F having ring of integers . Given a character X : T/T () → Cx on the torus T, extended trivially to the Borel subgroup B, an extremely important class of functions in representation theory are linear functionals of the form: : iG/B(x) → C. Consider a related type of linear functional that arises from doing a similar induction on the universal character χuniv : T/T(O) → C[P∨] mapping πµ → πµ. We are interested in the special functionals induced from this universal character: L : iG B(χ−1 univ) → C[P∨]. Some important examples of these special functionals include the Spherical functional, the Whittaker functional, and the Bessel model. These linear functionals also arise from our group G within a different context.
Let I be the Iwahori subgroup of G an let Ho denote the Hecke algebra, and Ho the finite Hecke algebra of G. Take to be a character on Ho and let V=Ind H/Ho(), then we can consider the special functions Fv : H → V as done in the work of Brubaker, Bump and Friedberg [1]. The purpose of this work is to provide an algebraic framework for explaining this coincidence and to use it as a dictionary to find new examples of interesting functionals. In particular we explore this topic from the finite field perspective as motivated by certain conjectures in the work of Kawanaka [2] concerning the Gelfand-Graev representation, which can be viewed as the Whittaker functional for the finite field case. Kawanaka provides a construction of generalized Gelfand-Graev representations (gGGrs) with the goal of classifying the irreducible representations of a finite reductive group G by using multiplicities of irreducible representations of G in gGGrs. We are interested in better understanding these types of linear functionals as they are inherently important in representation theory. The functionals resulting from these constructions provide information about the local components needed to construct integral representations of L-functions, around which many conjectures of the Langlands program are centered.Kenney, Meagan. (2025). Induced representations for finite groups of Lie type as Hecke algebra modules. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278210
Interplay between superconductivity and charge-orbital nematicity in iron chalcogenide materials
No full textUniversity of Minnesota Ph.D. dissertation. August 2025. Major: Physics. Advisor: Andrey Chubukov. 1 computer file (PDF); ix, 131 pages.In this dissertation, we present a comprehensive investigation of the phase diagram of Fe-chalcogenide materials, focusing on pure and doped FeSe-based systems. These compounds are multi-band metals in the normal state and exhibit strong orbital correlations. Their phase diagram is dominated by two distinct ordered phases: a nematic phase, which breaks the C4 rotational symmetry, and a superconducting phase, which breaks the U(1) gauge symmetry. Our goal is to understand the interplay between these two orders across different regions of the phase diagram. We focus on two representative limits: (i) superconductivity emerging within a finite nematic phase (“nematic superconductivity”), and (ii) superconductivity developing in the tetragonal phase without long-range nematic order but in close proximity to its onset, where nematic fluctuations are strong. This thesis presents a detailed analysis of both regimes.Islam, Kazi Ranjibul. (2025). Interplay between superconductivity and charge-orbital nematicity in iron chalcogenide materials. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278198
Minutes: Senate Committee on Equity, Access, and Diversity: February 25, 2025
No full textIn these minutes: Welcome; Equal Employment Opportunity Commission (EEOC) on the handling of discrimination; University of Minnesota Protection for Undocumented and Non-Citizen Member
The Roles of Cognitive Appraisal, Work Engagement, and Job Burnout in the Relationship Between Job Autonomy and Innovative Work Behavior
No full textA Plan B Research Project submitted to the faculty of the University of Minnesota by Luke James Pederson in partial fulfillment of the requirements for the degree Master of Arts, February 2025. This item has been modified from the original to redact the signature present.Engaging in innovative work behaviors (IWB) can improve the productivity and sustainability of organizations (Lee & Hong, 2014). At the same time, engaging in these behaviors can provide employees a sense of purpose and meaning in their work, which may increase their motivation (Chen et al., 2022). This study examined the roles of cognitive appraisal, work engagement (WE), and job burnout (JB) as serial mediators in the relationship between job autonomy (JA) and IWB for health and human service professionals (HHSPs). A convenience sample of 607 HHSPs accessed a survey on Qualtrics via a link provided through email and social media and responded to sociodemographic and job-related items, as well as items measuring JA, cognitive appraisal, WE, JB, IWB, and work innovation (WI). Results showed that cognitive appraisal, WE, and JB mediated the relationship between JA and IWB, while WI accounted for variation in IWB that could not be explained by the other variables. To our knowledge, this is the first study to have examined cognitive appraisal and JB as mediators and WI as a covariate in the JA-IWB relationship. The findings provided new knowledge about how cognitive appraisal and well- being outcomes (WE and JB) influence the dynamic JA-IWB relationship, which can affect HHSPs’ propensity to engage in IWB.Financial support for this research was provided by the University of Minnesota Duluth Department of Psychology Internal GrantPederson, Luke James. (2025). The Roles of Cognitive Appraisal, Work Engagement, and Job Burnout in the Relationship Between Job Autonomy and Innovative Work Behavior. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271559
Understanding the Physical and Chemical Stability of Permeate Powders
No full textFaculty Advisor: Job UbbinkThis research was supported by the Undergraduate Research Opportunities Program (UROP). Financial support from the National Dairy Council is gratefully acknowledged.Mirfakhraie, Nina. (2025). Understanding the Physical and Chemical Stability of Permeate Powders. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271269
Dynamic Wide-Baseline Stereo Vision on a Transformable UAV
No full textStereo vision is used extensively in robotics for applications such as 3D mapping and
obstacle detection. It can be employed on Unmanned Aerial Vehicles (UAVs) for these
purposes. However, a large baseline is often necessary to obtain depth estimates that
are sufficiently distant for a UAV to react to obstacles in time. A wide-baseline stereo
vision setup that takes advantage of the full wingspan of a fixed-wing UAV is a natural
solution to this problem. However, the dynamic nature of such a system, especially
due to wing deformation during flight, can present a challenging problem to solve.
Ideally, the stereo baseline should be dynamic to account for these deformations. The
work done in this area of robotics can be applied to an even more dynamic scenario: a
transformable UAV with the capabilities of both fixed-wing and quadrotor flight. This
paper addresses the problem of dynamic wide-baseline stereo vision on a transformable
UAV platform. It details the design, implementation, and testing of a system that
dynamically adapts to changes in both relative camera orientations and baseline. The
system utilizes a model-based kinematics approach, incorporating the known geometry
of the UAV and the current state of its servo-actuated joints to estimate the dynamic
orientation and baseline of the cameras. This approach is then fused with a visionbased approach that involves estimating the essential matrix from SIFT features for
a more robust recalibration approach in real-world scenarios. The ROS 2 middleware
facilitates communication between the various software components of this project. All
testing was conducted in a Gazebo simulation environment. The results demonstrate
the system’s ability to generate disparity maps even with significant changes in the
baseline and orientation of the cameras, validating the proposed dynamic stereo vision
approach.Brogni, Anthony. (2025). Dynamic Wide-Baseline Stereo Vision on a Transformable UAV. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271528
Unraveling metabolic health and diabetes: insights into Placental mitochondrial programming, O-GlcNAc/mTORC1 dynamics, and pancreatic Beta-cell function
No full textUniversity of Minnesota Ph.D. dissertation. January 2025. Major: Integrative Biology and Physiology. Advisor: Emilyn Alejandro. 1 computer file (PDF); ix, 182 pages.Type 2 diabetes (T2D) is a condition characterized by impaired blood glucose regulation and is associated with comorbidities such as cardiovascular disease, nerve and kidney damage, and vision loss. The etiology of T2D is complex, involving both genetic predispositions and environmental factors, which can exert influence as early as pregnancy and extend into adulthood. Despite significant advances in T2D treatment since the discovery of insulin nearly a century ago, the disease continues to rise in prevalence. Pancreatic β-cells, responsible for insulin production, play a crucial role in T2D progression, as their dysfunction directly contributes to the disease. Understanding the timing of metabolic health programming and the mechanisms underlying β-cell failure is essential for advancing T2D therapies. This study aims to elucidate mechanisms behind the development of T2D and metabolic disorders, focusing on the role of in utero programming during critical developmental windows and nutrient sensor crosstalk in regulating pancreatic β-cell mass and function. Key findings include: 1) Placental mitochondrial dysfunction leads to fetal growth restriction, specifically in the females and alter offspring metabolic responses to stressors; 2) Disruptions in nutrient-driven O-GlcNAc and mTORC1 signaling contribute to β-cell failure through distinct and overlapping effects on glucose-stimulus coupling and β-cell proliferation; and 3) O-GlcNAc-dependent autophagy is essential for maintaining β-cell function and glucose homeostasis. This work suggests that metabolic trajectories are shaped as early as during pregnancy, through placenta, with distinct differences between males and females. Stressors in both early and later life can disrupt nutrient sensor pathways, such as O-GlcNAc and mTORC1 signaling, contributing to β-cell dysfunction and the progression of T2D. We emphasize that chronic disturbances, whether an increase or decrease, in these signaling pathways are detrimental to β-cell survival and function. Mechanistically, the findings highlight autophagy as a key downstream regulator of insulin secretion, controlled by nutrient sensor pathways.Jo, Seokwon. (2025). Unraveling metabolic health and diabetes: insights into Placental mitochondrial programming, O-GlcNAc/mTORC1 dynamics, and pancreatic Beta-cell function. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271664
shy forms
No full textFaculty Advisor: Mathew ZefeldtHuber-Burns, Sarah. (2025). shy forms. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272018
Observation of Variable Stars and Astronomical Phenomena Using Autocorrelation to Calculate the Periodicity of Chi Cygni
No full textAutocorrelation is a commonly used method in time-series analysis that can be used to study the periodicity of irregularly sampled variable star data. The star of interest was Chi Cygni, which is a Mira Variable. Autocorrelation is applied to analyze the data found in the visual wavelength band. A tolerance variable is introduced to deal with irregularly sampled data sets. A period of 407 JD is obtained using a tolerance of 1 JD with an error of 0.258% and a period of 411 JD is obtained using a tolerance of 150 JD with an error of 0.723%.This research was supported by the Undergraduate Research Opportunities Program (UROP).Acharjee, Swastika. (2025). Observation of Variable Stars and Astronomical Phenomena Using Autocorrelation to Calculate the Periodicity of Chi Cygni. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272433