143258 research outputs found
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Neurodegeneration and behavior in rodents treated with chronic methamphetamine
No full textUniversity of Minnesota Ph.D. dissertation. 2025. Major: Pharmacology. Advisor: Steven Graves. 1 computer file (PDF); x, 122 pages.Thirty million people globally used amphetamine-type stimulants in 2022; while in the United States, 2.7 million people over the age of twelve reported using methamphetamine (meth) that same year. Meth is a powerful psychostimulant with a high propensity for abuse. The number of people using meth has been steadily increasing over the past decade alongside increases in meth-related hospitalizations, overdose deaths, and the number of individuals suffering from a meth-use disorder (MUD). Beyond being highly addictive, studies on individuals with a MUD have demonstrated that meth abuse can result in neurotoxicity alongside cognitive impairment. There are currently no treatments for either MUD or meth-induced neurotoxicity. Meth has recently been shown to cause a monoamine oxidase (MAO)-dependent increase of mitochondrial oxidative stress in catecholaminergic substantia nigra pars compacta (SNc) dopamine and locus coeruleus (LC) norepinephrine axons. Moreover, it has been demonstrated that applying chronic meth treatment (28 days of 5mg/kg injections once per day) results in degeneration of SNc and LC neurons and axons, and pre-treatment using an MAO isoform B inhibitor or mitochondrial antioxidant during meth administration prevents degeneration. These results demonstrate that meth-induced MAO-dependent mitochondrial oxidative stress in catecholaminergic axons is necessary for degeneration of SNc or LC neurons and axons following 28 days of meth administration. While it was shown that SNc cell loss does not occur after 14 days of this meth treatment regimen, it is unclear whether axon loss begins at this point and whether axonal loss precedes somatic loss in these regions. Additionally, while chronic meth use in humans is correlated with cognitive impairment, it is unclear if chronic meth-induced degeneration in rodent models results in behavioral deficits. My thesis work here, building on clinical and pre-clinical research of meth-induced catecholaminergic neurotoxicity and degeneration that has been carried out up to this point (Chapter 1), for the first time, demonstrates that chronic meth treatment results in SNc and LC axon loss prior to somatic degeneration in male mice and that pre-treatment with MAO isoform A and B inhibitor phenelzine is neuroprotective, while female mice are resistant to catecholaminergic degeneration (Chapter 2). Then, I show that chronic meth administration, which causes SNc and LC degeneration, does not result in novel object recognition or fear memory deficits in male mice but does cause reduced locomotion in both male and female mice (Chapter 3). Finally, I discuss my findings (Chapter 4) within the context of prior meth neurotoxicity literature, expand on the sex differences noted in Chapter 2, and examine links between chronic meth-induced neurodegeneration and neurodegenerative disorders.Pilski, Alexander. (2025). Neurodegeneration and behavior in rodents treated with chronic methamphetamine. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271365
WorldQuest Trivia Competition (2025-04-01)
No full textApril 1, 2025; Check-in at 6:00 pm; Dinner starts at 6:15 pm; Registration due by March 27th; Team size should be 6 to 8 players (some exceptions may be made); Team prizes and door prizes awardedRoyal D. Alworth, Jr. Institute for International StudiesUniversity of Minnesota Duluth. Royal D. Alworth, Jr. Institute for International Studies. (2025). WorldQuest Trivia Competition (2025-04-01). Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272306
University of Minnesota named #1 alien hotspot according to no one
No full text10:02The “true” tales of glowing green extraterrestrials wreaking havoc at the University of Minnesota, from eerie greenhouse encounters to chaotic frat house invasions.Heinen, Ceci. (2025). University of Minnesota named #1 alien hotspot according to no one. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272902
Lyme Disease: The Mystery of a Hidden Pandemic (2025-03-11)
No full textTuesday, March 11, 5-7 pm; University of Minnesota, Medical School Duluth Campus, 1035 University Drive Duluth, MN 55812; Open to all! Public parking available in Gold LotSpring showcase; Presented by Benjamin Clarke, PhD, Professor, Faculty, PhD Program in Biochemistry, Molecular Biology and BiophysicsUniversity of Minnesota Duluth. Medical School, Duluth Campus. (2025). Lyme Disease: The Mystery of a Hidden Pandemic (2025-03-11). Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272206
Y-Haplogroup Investigation for 4 Ancient Caribbean Individuals
No full textProduced in collaboration with the University of Minnesota Anthropological Genetics LabThis poster describes the process and outcome of an investigation into the Y-chromosome lineages of ancient Caribbean individuals. Y chromosome haplogroup identification is important for the reconstruction of Caribbean patrilineal ancestries given the effects of European colonization on the region. Male biased admixture during colonization has obstructed reconstruction of indigenous Y haplogroup identities in the region, so ancient DNA is a valuable tool to answer these questions. Background information, my contribution to Dr. Maria Nieves-Colón's broader Caribbean Genomics project, and visualization of the results thus far are included in this poster. This work has been completed as part of an undergraduate research opportunity through the UROP program.This research was supported by the Undergraduate Research Opportunities Program (UROP).Holden, Abigail; Nieves-Colón, Maria. (2025). Y-Haplogroup Investigation for 4 Ancient Caribbean Individuals. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271649
Data and code for A Descriptive Analysis of Inter- and Intra-Observer Agreement of Body Condition Scoring Methods in Dairy Cattle
No full text# BCS_Final Repository
This repository contains all data, scripts, and outputs used for analyzing body condition scores (BCS) in dairy cows using multiple input sources. Below is a description of the folder structure and file contents to help you navigate the repository.
## 00_Data
This folder contains all raw and pre-processed data used in the analysis.
Subfolders:
- CE_BCS/
Contains body condition scores derived from camera-based technology (AUTO).
- Farm_BCS/
Contains body condition scores recorded by trained observers during on-farm evaluations.
- Side_Image_BCS/
Contains body condition scores generated from side-profile cow images.
Additional Files:
- all_cow_frsh.csv, fresh.csv, etc.
Files containing cow-level information including fresh dates, IDs, and lactation records.
- Random_Order.csv
File that specifies the randomized order in which images were reviewed or presented.
## 01_Data_Manipulation
This folder contains R scripts used to clean and process the raw data into analysis-ready formats.
- Scripts are organized and named based on their role in preparing specific data sources or merging datasets.
- Refer to individual script names for details on processing steps.
## 02_Output
This folder contains all outputs used in reporting and analysis.
- Includes R scripts used to calculate results and generate visualizations (e.g., figures for presentations or manuscripts).
- PNG images used in result summaries are also stored here.
## QMD Files (Quarto Markdown)
Located in the root or associated folders, these files were used to generate draft reports and internal reviews.
- They include embedded figures, tables, and references to data stored in the folders above.
- Useful for understanding how different components (e.g., images, scores, cow metadata) were linked and evaluated.
## Summary
This repository supports full transparency and reproducibility of the BCS analysis pipeline. All data sources, transformation scripts, and output materials are clearly organized to assist future users in reviewing, reusing, or extending the work.
For questions or collaboration inquiries, please contact the repository owner.This repository contains data and R scripts used for processing, analyzing, and visualizing body condition scores (BCS) in dairy cows. It includes raw BCS data collected from three sources—automated camera technology, on-farm observations, and image-based scoring—as well as cow metadata. The repository also provides R scripts for cleaning and merging datasets, generating figures, and producing summary statistics. Outputs such as plots, tables, and draft reports (QMD files) used for internal review are included to support reproducibility and transparency of the analysis workflow.Swartz, Drew; Shepley, Elise; Caixeta, Luciano; Cramer, Gerard. (2025). Data and code for A Descriptive Analysis of Inter- and Intra-Observer Agreement of Body Condition Scoring Methods in Dairy Cattle. Retrieved from the Data Repository for the University of Minnesota (DRUM), https://hdl.handle.net/11299/272427
Springing ahead is more harmful than helpful
No full text11:44The “springing ahead” phenomenon that comes from Daylight Saving Time is more than just losing an hour of sleep. It also means more public safety accidents and worse mental health.Lassiter, Alex; Akingbola, Akinbolaji; Christianson, Troy. (2025). Springing ahead is more harmful than helpful. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272904
Semi-dry biofilm reactors for efficient gas phase bioprocessing applications
No full textUniversity of Minnesota Ph.D. dissertation. January 2025. Major: Bioproducts/Biosystems Science Engineering and Management. Advisor: Ping Wang. 1 computer file (PDF); xiv, 179 pages.Traditional liquid-phase bioprocessing systems face significant challenges in achieving efficient degradation of airborne volatile organic compounds (VOCs) and maximizing biofuel production, largely due to complex mass transfer resistances and kinetic limitations inherent in gas-liquid-solid reaction environments. These barriers result in reduced efficiency in VOC removal and restrict the potential productivity of biofuel fermentation processes. To address these challenges, this research explores innovative gas-phase bioprocessing strategies using biofilm reactors, aiming to enhance the efficiency of bioprocessing and overcome the limitations associated with liquid media. The initial part of the study focuses on VOC biofiltration and biodegradation, processes typically constrained by factors such as VOC aqueous solubility, mass transfer resistance across multiple layers, and cellular metabolic kinetics. Recent advancements in this field are analyzed to introduce a simplified evaluation framework that leverages inherent mass transfer and kinetic parameters to establish a universal space-time productivity (effectiveness) index. This index provides a standardized metric for comparing process efficiencies across various reaction systems, allowing for an objective assessment of different engineering designs. Such a standardized evaluation not only reveals the limitations of current technologies but also offers guidance for future research efforts to address critical engineering constraints, thus advancing the field of VOC biofiltration. Building on this analysis, the research presents an innovative “dry” biofilm reactor system to enhance VOC degradation efficiency by directly exposing Pseudomonas putida F1 biofilms, supported on carbonized cellulosic fibers, to gaseous VOC substrates. By eliminating the need for bulk aqueous-phase media, this approach removes aqueous-phase mass transfer resistance, facilitating more efficient VOC capture and degradation. Using toluene as a model VOC, the biofilm system achieved a specific growth rate of 0.425 day⁻¹ under optimal conditions (300 p.p.m. toluene and 80% relative humidity). Long-term degradation tests conducted in a tubular packed bed reactor demonstrated a toluene degradation rate of 2.5 mg gDCW⁻¹ h⁻¹ during the initial growth phase. Importantly, the biofilm retained its biodegradation activity in the stationary phase, achieving a toluene degradation rate of 1.9 mg gDCW⁻¹ h⁻¹, with simultaneous CO₂ release at 6.4 mg gDCW⁻¹ h⁻¹, indicating complete carbon conversion of the substrate. Operated without any bulk liquid medium phase, the biofilm achieved direct degradation of gas‐phase VOC at rates of about one order of magnitude higher than what has been previously reported for liquid culturing or immobilized cells. These findings demonstrate the potential of dry biofilm reactors to efficiently degrade VOCs without requiring large amounts of water, representing a significant advancement in sustainable air pollution control. The second part of this study addresses the productivity limitations in biofuel fermentation, particularly in ethanol production. Traditional liquid-phase fermentation has reached its productivity ceiling, prompting a shift to alternative methods. In this research, a hollow fiber membrane (HFM)-supported biofilm reactor was developed to enable ethanol biosynthesis under gas-phase conditions. This design minimizes reaction volume and allows in situ ethanol recovery, significantly enhancing productivity. Under optimal operating conditions, the gas-phase reactor achieved a volumetric ethanol productivity of 37.5 g LBiomass⁻¹ h⁻¹ during the microbial growth phase and maintained productivity at 19.1 g LBiomass⁻¹ h⁻¹ during the stationary phase, with specific productivity rates of 0.58 g gDCW⁻¹ h⁻¹ and 0.047 g gDCW⁻¹ h⁻¹, respectively. Long-term operations demonstrated stable ethanol production, underscoring the potential of gas-phase bioprocessing to surpass the productivity limitations of liquid-phase systems. This liquid-free approach presents substantial potential for enhancing the efficiency and scalability of biofuel production systems. In summary, gas-phase bioprocessing using biofilm reactors offers a transformative solution for both environmental remediation and biofuel production. By eliminating mass transfer limitations inherent in liquid-phase systems, the proposed gas-phase strategies provide an efficient and sustainable pathway for VOC degradation and biofuel synthesis, opening new avenues for advancing bioprocessing technology.Xu, Chao. (2025). Semi-dry biofilm reactors for efficient gas phase bioprocessing applications. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/271688
UBE2A Syndrome Research Community Partnership Study
No full textFunded by a Masonic Institute for the Developing Brain Seed GrantRoberts, Caroline; Chubb, Laura; Farquhar, Erin; Gegziahber, Niyat; Gunderson, Jaclyn; Merbler, Alyssa; Byiers, Breanne; Eisengart, Julie. (2025). UBE2A Syndrome Research Community Partnership Study. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/270431
Nitrogen fertilizer management & surface water: Context, successes and challenges
No full textRuntime 28:05Today on the Advancing Nitrogen Smart Podcast we discuss nitrogen fertilizer management and surface water issues. When did we first become aware of nitrates appearing in surface water? What are some of the effects, and who is being affected? What are Minnesota's current nitrate-reduction strategy benchmarks - and are we on target to meet them? What are some of the challenges and success stories Minnesotans should know about? Which organizations can I contact if I'd like to become more involved? Additional resources: MPCA Nutrient Reduction Strategy (https://www.pca.state.mn.us/air-water-land-climate/reducing-nutrients-in-waters); Nitrogen Best Management Practices (BMPs) (https://www.mda.state.mn.us/pesticide-fertilizer/nitrogen-fertilizer-bmps-agricultural-lands) HUC-8 Watersheds (https://www.dnr.state.mn.us/whaf/key-concepts/ws_def.html); Soil and Water Conservation Districts (SWCDs) in Minnesota (https://bwsr.state.mn.us/soil-water-conservation-districts)Carlson, Brad; Kaiser, Daniel. (2025). Nitrogen fertilizer management & surface water: Context, successes and challenges. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/272888