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Data supporting Biofilm Formation Promotes Microplastic Mobility via Hydrodynamic Forces
No full textThe microscopy images were captured using a confocal microscope. The MATLAB code was used to process these images to quantify the biofilm area and identify transported beads. All resulting measurements are compiled and summarized in the spreadsheet.This dataset supports the manuscript “Biofilm Formation Promotes Microplastic Mobility via Hydrodynamic Forces.” It includes measurements of biofilm area and the percentage of transported beads under five different flow rates, as well as an example set of microscopy images and a MATLAB dataset used for image processing. In the manuscript, we demonstrate that the presence of biofilms alters the hydrodynamic forces acting on microplastic particles. Specifically, biofilms modify the local pressure field and generate lift forces strong enough to mobilize particles even under weak shear conditions.This study was supported by National Science Foundation CAREER Award EAR 2236497. Portions of this work were conducted in the Minnesota Nano Center, which is supported by the National Science Foundation through the National Nanotechnology Coordinated Infrastructure (NNCI) under Award Number ECCS-2025124.Wei, Guanju; Yang, Judy Q. (2025). Data supporting Biofilm Formation Promotes Microplastic Mobility via Hydrodynamic Forces. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://doi.org/10.13020/szz5-jf42
Left regular bands with symmetry
Get PDFUniversity of Minnesota Ph.D. dissertation. June 2025. Major: Mathematics. Advisor: Victor Reiner. 1 computer file (PDF); xi, 199 pages.Left regular bands (or LRBs) are a well-studied class of finite semigroups which have connections with Markov chains, combinatorics, and discrete geometry. Although their semigroup algebras are rarely semisimple, much of their representation theoretic and homological data is well-understood. One tool which has been particularly useful in making these structures so tractable is poset topology, as developed in the wealth of work on LRBs put forth by Margolis--Saliola--Steinberg. Many LRBs in the literature carry symmetries, meaning they come equipped with groups that naturally act by semigroup automorphisms. In such a setting, it is natural to examine the invariant subalgebra of the LRB semigroup algebra as well as the invariant theory of the entire semigroup algebra. For some LRBs, interesting combinatorial structures---like Solomon's descent algebra and the derangement symmetric function---are known to arise when studying these topics. In this thesis, inspired by the work of Margolis--Saliola--Steinberg, we study LRBs with symmetry through the lens of group-equivariant poset topology. We first characterize when the invariant subalgebra of an LRB semigroup algebra is commutative or semisimple. Then, to understand the Cartan invariants of the invariant subalgebra as well as the invariant theory of the entire algebra, we study special decompositions of the semigroup algebras called invariant Peirce decompositions. For LRBs associated to hyperplane arrangements, there is a known connection between invariant Peirce decompositions and equivariant poset topology. In the case of the braid arrangement, we leverage this connection to carry out an in-depth analysis of the invariant Peirce decompositions. Our study both generalizes and unites work of Garsia--Reutenauer on the Cartan invariants of Solomon's descent algebra and Uyemura-Reyes on representations arising from shuffling processes. In joint work with B. Steinberg, we generalize the known connection between invariant Peirce decompositions and equivariant poset topology from LRBs associated to hyperplane arrangements to a larger class of LRBs known as CW LRBs. We then apply our generalization to understand the invariant Peirce decompositions for LRBs associated to CAT(0)-cube complexes, an exciting new example of CW LRBs recently discovered by Margolis--Saliola--Steinberg and Bandelt--Chepoi--Knauer. Additionally---and also in joint work with Steinberg---we develop a formula for the invariant Peirce decompositions of LRBs with hereditary semigroup algebras in terms of equivariant poset topology. We show that our formula recovers past work of the author with S. Brauner and V. Reiner on the free LRB and its q-analogue. Along the way, we find a new formula for the derangement symmetric function. Finally, an expository goal of this thesis is to explore examples of LRBs associated to CAT(0)-cube complexes. In particular, we explicitly work out the semigroup structure for LRBs arising from an especially combinatorial subclass of CAT(0)-cube complexes; this subclass includes Billera--Holmes--Vogtmann's space of phylogenetic trees.Commins, Patricia. (2025). Left regular bands with symmetry. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276743
Thomas J. Farrell's Reflections on His Obsessions, and Walter J. Ong's Thought
Get PDFSee the above abstract.In the wide-ranging and deeply personal 2,988-word review essay titled "Thomas J. Farrell's Reflections on His Obsessions, and Walter J. Ong's Thought," I reflect on two of my obsessions and discuss each one in terms of the Jungian psychotherapist and psychological theorist Robert Moore's theory of the eight archetypes of maturity in the human psyche, each of which is accompanied by two bipolar "shadow" forms. Each of my two obsessions invovles a "shadow" form of a different archetype of maturity in my psyche. As the title of my review essay indicates, I also discuss the work of my former teacher the American Jesuit Walter J. Ong (1912-2003; Ph.D. in English, Harvard University, 1955) of Saint Louis University, the Jesuit university in the City of St. Louis, Missouri (USA), where, over the years, I took five courses from him.N/AFarrell, Thomas. (2025). Thomas J. Farrell's Reflections on His Obsessions, and Walter J. Ong's Thought. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277711
Effects of Cardiac Resynchronization Therapy (CRT) Optimization with Changes in Programming from Biventricular to LV-only Pacing
Get PDFBackground: We have previously demonstrated that optimization of CRT nonresponders using electrical dyssynchrony mapping (EDM) significantly improves left ventricular (LV) size and systolic function. The specific effects of optimization from biventricular (BiV) pacing to LV- only pacing on LV function and CRT battery life are not known.
Objective: To assess the effects of optimization, using a novel measure of electrical wavefront fusion and cancellation called EDM, on LV size, systolic function, and battery life in patients optimized from BiV to LV-only pacing.
Methods: We studied 43 systolic heart failure (HF) patients with nonresponse or incomplete response to CRT who were optimized using EDM from BiV pacing to LV-only pacing 2.3 ± 2.5 years post-implantation. Electrical dyssynchrony was quantified by cardiac resynchronization index (CRI), calculated as % change in the area under QRS curves between all combinations of 6 anterior and 3 posterior electrograms, compared to native conduction with pacing turned off (CRI values 0-100%). CRI was measured in 20-ms increments at all practical combinations of atrial-ventricular delay (AVD) and ventricular-ventricular delay (VVD) (during BiV pacing), and across AVD (during LV-only pacing). Patients were programmed to optimal CRI, defined as the highest CRI value observed among the tested pacing configurations. Change in battery life was calculated as the difference in years of average end-of-life from multiple device checks before and after optimization. Echocardiograms were performed prior to EDM and 4-6 months after EDM and read in a blinded fashion.
Results: Baseline patient characteristics were as follows: age 66 ± 10 yrs, male 77%, ischemic etiology 40%, QRS duration 154 ± 27 ms, EF 26.8 ± 9.9 %. EF improved to 30.7 ± 6.3 % with CRT. Table shows significant improvements in CRI (40.5 ± 28.5 %), LV ejection fraction (3.9 ± 3.9 %), LVESV (10.8 ± 20.9 mL), LVEDV (7.9 ± 24.7 mL), LV global longitudinal strain (0.9 ± 2.1), and device battery life (0.9 ± 1.2 years) following CRT optimization.
Conclusion: CRT nonresponders and incomplete responders optimized using EDM from BiV pacing to LV-only pacing had significant improvements in LVEF, LV volumes, LV longitudinal strain, and device battery longevity. This approach to CRT programming has the potential to produce both improvements in patient outcomes and a reduction in the cost of care for HF patients with CRT.Miyanoorwala, Ibby. (2025). Effects of Cardiac Resynchronization Therapy (CRT) Optimization with Changes in Programming from Biventricular to LV-only Pacing. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277685
Minutes: Faculty Senate: April 24, 2025
Get PDFUniversity of Minnesota: Faculty Senate. (2025). Minutes: Faculty Senate: April 24, 2025. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276666
Data for: Tree defenses, host choice, and reproductive success of a native bark beetle under novel outbreak conditions, 2011-2013 & 2022-2023, Beltrami Island State Forest, MN
No full textData consists of four different CSV files. One contains raw field data regarding tree characteristics and year of beetle colonization. One contains raw and calculated field data regarding beetle reproductive success based on tree. One contains raw data regarding resin duct size and location in tree core annual rings. One contains raw and calculated tree core metrics regarding ring widths, growth trends, and resin duct density.This dataset was initially collected as an observational study of tree-bark beetle dynamics during an outbreak of eastern larch beetle in eastern larch forests in Beltrami Island State Forest, Minnesota. Field data was collected from 2011-2013 and includes tree level measurements of size, microsite stand density, and phloem characteristics, as well as tree level measurements of beetle attack density and reproductive success. During the initial field season tree cores were collected to determine tree age. These cores were subsequently scanned in 2022-2023 with high resolution photography to measure core level traits regarding ring width and resin duct density. These data were used to understand the relationship between tree defensive capacity and beetle reproductive success.McKnight Land-Grant ProfessorshipUS Forest Service Evaluation Monitoring Grant NC-EM-B-12-01Hubachek Wilderness and Research FundJosephine and Waldemore Mohl FundHugo J and Helen K Pawek Fellowship in Forest ResourcesHenry L Hansen Forest Ecology FellowshipMAES Project MIN-42-108MAES Project MIN-17-117Minnesota Environment and Natural Resources Trust Fund project 2020-047Graham, Grace; Windmuller-Campione, Marcella; Griffin, Daniel; McKee, Fraser; Aukema, Brian. (2025). Data for: Tree defenses, host choice, and reproductive success of a native bark beetle under novel outbreak conditions, 2011-2013 & 2022-2023, Beltrami Island State Forest, MN. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://doi.org/10.13020/9gn2-9y11
How Brazilian Legal Actors Debate the Rise of Negotiated Justice
Get PDFThis study investigates how Brazilian legal actors interpret and debate the rise of negotiated justice and the influence of American criminal law, particularly following the introduction of the Acordo de Não Persecução Penal (ANPP) under Law 13.964/2019. Drawing on 68 articles published in IBCCRIM newsletters from 1993 to 2025, the research employs qualitative content analysis using NVivo to code legal commentaries by tone, theme, and argumentative focus. The findings reveal a shift in perceptions over time: while early debates were predominantly skeptical (emphasizing concerns over prosecutorial power, due process, and the risks of importing U.S. models) later discussions became more pragmatic, viewing the ANPP as a tool compatible with Brazil’s civil law traditions and judicial oversight. This transformation suggests that Brazilian legal actors have progressively redefined negotiated justice as both an efficiency mechanism and a culturally adapted practice rather than a direct transplantation of plea bargaining. Ultimately, the study highlights how evolving professional interpretations mirror broader tensions between fairness, efficiency, and the localization of global legal norms within Brazil’s constitutional framework.This research was supported by the Undergraduate Research Opportunities Program (UROP).Duarte Possebon, Daphine. (2025). How Brazilian Legal Actors Debate the Rise of Negotiated Justice. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277250
Minutes: Senate Committee on Academic Freedom and Tenure: September 12, 2025
Get PDFIn these minutes: Welcome and Introductions; Collegiate Personnel Plans Update; Plans for Reporting on Long-term Appointments; Policy Review: Academic Appointments with Teaching Functions; Information Item: Academic Freedom Symposium; Committee Discussion: Planning for 2025-2026University of Minnesota: Senate Committee on Academic Freedom and Tenure. (2025). Minutes: Senate Committee on Academic Freedom and Tenure: September 12, 2025. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276676
Usability and feasibility of in-home vibro-tactile stimulation for treating voice symptoms in laryngeal dystonia
Get PDFUniversity of Minnesota M.S. thesis. May 2025. Major: Kinesiology. Advisor: jurgen Konczak. 1 computer file (PDF); viii, 41 pages.Laryngeal dystonia (LD) is a chronic neurological voice disorder treated primarily with Botulinum neurotoxin (BoNT) injections. Recent studies suggest that laryngeal vibrotactile stimulation (VTS) may reduce vocal effort and improve voice quality. This study evaluated the feasibility and usability of an in-home VTS device in 32 participants with adductor or abductor LD over eight weeks. Participants applied VTS for 20 minutes/day, initially following a fixed protocol, then self-regulating usage. Results showed high adherence (93%) and user satisfaction (75% reported no difficulty). VTS reduced perceived speech effort by 13.5% during the first four weeks, and 63% of participants reported improvements. Voice quality ratings increased from neutral (2.9) to noticeable (3.8), with effects lasting beyond 24 hours for some. No significant differences were observed between LD types or BoNT use. Most participants preferred the collar over skin tape. Findings support VTS as a feasible, non-invasive, and patient-accepted in-home intervention for LD.Amini, Shima. (2025). Usability and feasibility of in-home vibro-tactile stimulation for treating voice symptoms in laryngeal dystonia. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/276695
Data for "Effects of fibroblast growth factor 2 on muscle precursor cells from mouse limb and extraocular muscle"
No full textFibroblast growth factor 2 (FGF2) is known to play a role in skeletal muscle development and growth. We examined two populations of myogenic precursor cells for their responses to FGF2 in vitro using both extraocular and limb skeletal muscle. Fluorescence-activated cell sorting (FACS) was used to isolate two different populations of myogenic precursor cells, the EECD34 cells (positive for CD34, and negative for Sca1, CD31, and CD45) and PAX7-positive cells, from tibialis anterior and extraocular muscles of mice. These cells were cultured and treated with either proliferation or differentiation media in the absence or the presence of FGF2, followed by assays to determine the effects on proliferation and differentiation. EECD34 cells and PAX7-positive cells from both muscles responded to FGF2 with significantly increased proliferation. Both myogenic precursor cell populations from each muscle type showed increased percentage of desmin-positive mononucleated cells, but decreased rates of fusion into multinucleated myotubes in the presence of FGF2 in this in vitro system relative to control cells. FGF2 has pleiotropic effects on skeletal muscles. Contrary to the literature, FGF2 did not inhibit differentiation, but did appear to decrease fusion into multinucleated myofibers in vitro. Examination of immunostaining for myomerger in differentiating PAX7-positive cells in the presence or absence of FGF2 demonstrated a significant reduction of expression in the presence of elevated FGF2 levels. These results provide a potential mechanism for reduction in myofiber number and size in the extraocular muscles in individuals with Apert syndrome, where FGF receptor 2 mutations maintain the receptor in an activated state resulting in significantly reduced myofiber size.National Eye Institute RO1EY15313
National Science Foundation NRT-UtB: Graduate Training Program in Sensory Science
National Eye Institute NIHT32EY025187
Minnesota Lions Gift of SightWinker, Austin J; Johnson, Laura L; Jadhav, Ria; Nguyen, Catherine; Hitch, Elizabeth; McLoon, Linda K. (2025). Data for "Effects of fibroblast growth factor 2 on muscle precursor cells from mouse limb and extraocular muscle". Retrieved from the Data Repository for the University of Minnesota (DRUM), https://doi.org/10.13020/VR2S-3739