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Do not put red with our children: a thematic analysis of Somali perspectives on score reporting for State assessments
No full textUniversity of Minnesota Ph.D. dissertation. 2025. Major: Educational Psychology. Advisor: Michael Rodriguez. 1 computer file (PDF); x, 175 pages.Under the Every Student Succeeds Act, states must provide parents with score reports for their statewide accountability assessments. Although many of these exams are designed primarily for system-level accountability, parents are given little guidance and expected to interpret individual student score reports, which raises validity concerns and underscores the need to understand how families make meaning from these reports. This is especially true for communities who do not equitably receive the report in their primary language, such as the Somali community in Minnesota. This quasi-deductive phenomenological study, guided by questions of access and understanding, explores the lived experiences of Somali parents as they navigate these score reports. Through a series of eight focus groups conducted in Somali, parents discussed their experiences with the official Minnesota Comprehensive Assessments (MCA) score report before reviewing and reacting to mock-up reports designed using published best practices in both English and Somali. Data were analyzed through Reflexive Thematic Analysis, resulting in five themes. Findings indicate that direct translation is insufficient; reports must be culturally sustaining to be truly accessible. Parents expressed a strong desire to understand the reports, yet faced systemic barriers that prevented them from doing so. Many interpreted static scores as indicators of progress, reflecting their desire for tools that help them understand their children’s growth. At the same time, they relied on salient visual cues to make quick, binary judgments about performance while overlooking technical measurement features. Ultimately, parents viewed score reports as a call to action, motivating them to engage with teachers and advocate for their children. This study concludes that even when individual scores have limited utility, the reports themselves can serve as powerful tools for fostering parent engagement. The results yield actionable recommendations for developing more equitable score reporting practices that prioritize the perspectives and needs of marginalized families.Ihlenfeldt, Samuel. (2025). Do not put red with our children: a thematic analysis of Somali perspectives on score reporting for State assessments. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278197
Community context shapes evolutionary trajectories in microbial communities
No full textUniversity of Minnesota Ph.D. dissertation.May 2025. Major: Ecology, Evolution and Behavior. Advisor: William Harcombe. 1 computer file (PDF); ix, 283 pages.All life on Earth exists in an ecological context, what Darwin called the “tangled bank”, where “elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us”. In the tangled bank, organisms participate in diverse relationships, competing for space and resources, eating one another, killing each other with chemicals, and engaging in mutual aid. The strength and sign of ecological interactions can change with abiotic and biotic context and over the course of evolutionary time. For this reason, understanding the feedback between ecological and evolutionary processes in complex communities is challenging, particularly when organisms from multiple trophic levels are present. How does increasing community complexity change the nature of the pairwise interactions in which a focal organism is engaged? When and how does community context shape or constrain evolution? I test these questions using various modeling approaches and a synthetic microbial community. First, I examine the impact of ecological interactions between bacterial hosts on the evolution of host range in their viral predators. Next, I demonstrate that intracellular parasites of microbes can change microbial community structure and productivity by changing the metabolism of their hosts. Finally, I investigate how key ecosystem properties like spatial structure and growth rate determine the strength of ecological interactions and therefore shape selection on the production of diffusive metabolites like toxins. Taken together, my work emphasizes that eco-evolutionary dynamics in the tangled bank can be governed by predictable processes and sets the stage for more effective management of microbial communities for biomedical and bioengineering purposes.Bisesi, Ave. (2025). Community context shapes evolutionary trajectories in microbial communities. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278138
Novel single cell multiomics approaches to overcome barriers to interspecies chimerism for generating exogenic organs and cells
No full textUniversity of Minnesota Ph.D. dissertation. January 2025. Major: Molecular, Cellular, Developmental Biology and Genetics. Advisor: Walter Low. 1 computer file (PDF); v, 78 pages.There is a massive shortage of organ donors available for transplantation therapy, and millions of people die every year waiting for donor organs. The fields of interspecies chimerism and blastocyst complementation have shown promise towards addressing this organ shortage. The goal of these fields is to develop transplantable human organs in host animals like pigs, that can then be extracted and used in the clinic for transplantation therapy. While these fields hold great promise, there are still barriers that need to be overcome.One of the major barriers to successful interspecies chimerism is the mismatch in the developmental stages of the donor and the host cells, in the chimeric embryo. In Aim 1, we interrogated scRNA sequenced datasets of early embryos and stem cells from four commonly used donor and host species- human, marmoset, mouse, and pig. We found that the human blastocyst (E6/E7) best matched with the gastrulating mouse embryo (E6-E6.75), the marmoset late inner cell mass, and the pig late blastocyst.
Another major barrier to successful chimerism is the mismatch in developmental speeds between the donor and host cells in the chimeric embryos. To address this barrier, there is first a need to define developmental speed at the single cell level. In Aim 2, we developed a novel single cell (sc) multiomics approach to simultaneously analyze replication timing (RT) and gene expression, to define developmental speed. RT is an epigenetic cell-type specific feature, that allows us to analyze how genes replicate, early or late, during the S-phase of the cell cycle. We optimized this approach in a well-established cancer cell line HepG2 and for the first time, demonstrated RT and gene expression interactions within single cells. We were able to capture conserved patterns between cells and cell-to-cell variations.
Mouse is the most commonly used host embryo in chimerism studies. Hence, in aim 3, we analyzed wildtype (WT) early mouse preimplantation embryos using the sc-multiomics approach. Analysis of the WT mouse embryos provided us with novel chromatin accessibility, genome, and transcriptome trends that could be observed for the first time, using the sc- multiomics approach. The techniques used in this aim can be used to analyze donor and host cells in chimeric embryos. This provides us with molecular targets for enhancing interspecies chimerism and driving the field towards its end goal of generating exogenic human organs for transplantation therapy in the clinic.Shetty, Anala. (2025). Novel single cell multiomics approaches to overcome barriers to interspecies chimerism for generating exogenic organs and cells. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278080
Enhancement of pea protein solubility and thermal stability for beverage applications via endogenous Maillard-induced glycation
No full textUniversity of Minnesota M.S. thesis. June 2025. Major: Food Science. Advisor: Baraem Ismail. 1 computer file (PDF); xiv, 128 pages.The growing demand for non-soy plant proteins has fueled the expansion of the pea protein market. Pea protein is a prominent alternative to soy protein due to its wide availability, sustainability, non-GMO status, and low allergenic potential. However, broader adoption of pea protein in various food applications still faces challenges, particularly regarding its low solubility and thermal stability. Consequently, there is considerable interest in modifying the structure of pea protein to enhance its solubility and thermal stability, making it more versatile. This work utilized a scalable, clean-label process to endogenously glycate and purify pea protein. The optimization of scale-up maltodextrin (SUMD) production from pea starch with a targeted dextrose equivalent (DE) was successfully achieved. The SUMD (11.2 DE) was used for controlled and limited Maillard-induced glycation of pea protein. In this study, the glycation process was effectively confined to the initial stages, resulting in a moderate blockage of amine groups (approximately 16%) after 12 hours of incubation at 60°C and 49% relative humidity. The partially glycated pea protein (PG-PP) underwent hydrophobic interaction chromatography (HIC) or alkaline solubilization with isoelectric precipitation (AE-IEP) to remove unreacted carbohydrates. For the first time, a compositional comparison was made between purified PG-PP samples obtained through two different purification processes. AE-IEP resulted in a purified PG-PP with a protein purity of 75.9%, while HIC resulted in a purified PG-PP with a protein purity of 65.7%. Additional evaluation of the purified PG-PP via AE-IEP was conducted to determine its protein molecular weight distribution, thermal denaturation properties, surface characteristics, solubility, and thermal stability. Compared to its non-glycated counterpart (scaled-up pea protein isolate, SUPPI), the purified PG-PP exhibited increased surface charge at pH 7, which reduced protein–protein interactions and promoted protein–water interactions. Furthermore, purification by AE-IEP partially removed denatured and polymerized proteins, enriching the hydrophilic and soluble protein fractions in the purified PG-PP. As a result, the purified PG-PP demonstrated high solubility (up to 85%) at pH 7.0 under both heated and non-heated conditions. This work provided essential insights that will inform future studies aimed at scaling the production of value-added pea protein ingredients for high-protein beverage applications.Boerboom, Allison. (2025). Enhancement of pea protein solubility and thermal stability for beverage applications via endogenous Maillard-induced glycation. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278001
Border abolition in (re)integration support: incarceration, deportation, and an Abolitionist Praxis in the Tijuana Borderlands
No full textUniversity of Minnesota Ph.D. dissertation. August 2025. Major: American Studies. Advisors: Jimmy Patiño, Bianet Castellanos. 1 computer file (PDF); ix 148 pages.After a surge in Mexican family migrations to the United States during the mid 1970s, Chicano/Mexicano immigrant communities in states like California increasingly formed and sustained transnational support networks that paid particular attention to an increase in border policing and migrant criminalization. These networks shifted and adjusted to organize themselves against anti-immigrant laws and rhetoric. Mexican families and their transnational support networks organized against imprisonment and deportation, state-sanctioned punishments. Border Abolition in (Re)integration Support: Incarceration, Deportation, and an Abolitionist Praxis in Tijuana’s Borderlands follows my uncle Jose’s journey through his migrant barrio youthood, incarceration in the California State Prison System, and (re)integration to Tijuana after deportation from incarceration. Employing autoethnography, testimonio, and archival analysis as primary methods, I examine the intricacies of how his support networks refused to abandon the life of a criminalized migrant amidst binational carcerality in the California-Tijuana borderlands region. I argue that Mexican formerly incarcerated deportees and their transnational support networks conceive a border abolitionist praxis.Padilla, Kiara. (2025). Border abolition in (re)integration support: incarceration, deportation, and an Abolitionist Praxis in the Tijuana Borderlands. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278055
Evaluating the morphological characteristics of fine aggregate using digital image analysis
No full textUniversity of Minnesota M.S. thesis. August 2025. Major: Civil Engineering. Advisor: Mihai Marasteanu. 1 computer file (PDF); v. 59 pages.Fine aggregates, plays a critical role in hot-mix asphalt (HMA) performance, due to their morphological characteristics, shape, angularity, and surface texture, which governs particle interlock, and overall pavement durability. Current, indirect method such as ASTM C1252, Standard Test Method for Uncompacted Void Content of Fine Aggregate (FAA Test) is standard test to evaluate the morphology of fine aggregate. No standardized test method measures aggregate morphology directly, although the advancement in image-based technology such as digital image analysis technique provides direct measurement of fine aggregate's morphology. This study evaluates fine aggregates found in Minnesota using both the FAA test and digital image analysis to compare their effectiveness in characterizing aggregate morphology. The FAA test assess bulk uncompacted void content, reflecting the combined effect of shape, angularity, and surface texture of fine aggregate, whereas digital image analysis evaluates it individually. Both test were done on same sample and a correlation analysis was performed. Additionally, statistical test is performed on the data obtained from the digital image analysis device.Khanal, Shambhavi. (2025). Evaluating the morphological characteristics of fine aggregate using digital image analysis. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277977
Development and characterization of a murine moderate controlled cortical impact model of traumatic brain injury
No full textUniversity of Minnesota M.S. thesis. August 2025. Major: Molecular, Cellular, Developmental Biology and Genetics. Advisor: Walter Low. 1 computer file (PDF); v, 44 pages.Traumatic brain injury (TBI) is a leading cause of long-term disability, with complex region-specific consequences that demand precise modeling. This study characterizes the structural, cellular, and functional impact of moderate anterior TBI in mice using a controlled cortical impact (CCI) model. Lesion volumes, quantified using 3D ultrasound, were consistent (2.4-2.7mm3). Histology revealed robust gliosis in perilesional regions with widespread microglial (Iba1) and astrocytic (GFAP) activation, extending bilaterally into the cortex and hippocampus while sparing the amygdala. Behaviorally, mice exhibited significant motor and spatial memory deficits, aligning with sensorimotor and hippocampal injury, while fear-conditioned learning remained intact, consistent with preserved amygdalar function. Together, these findings demonstrate that anterior CCI produces reproducible, regionally selective lesions that drive motor and hippocampal-dependent memory impairments while sparing fear-associated circuitry. Integration of 3D ultrasound with behavioral and histological analyses links lesion topography and neuroinflammation to functional outcomes, enhancing the translational relevance of this model.Erlanson, Olivia. (2025). Development and characterization of a murine moderate controlled cortical impact model of traumatic brain injury. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/277959
Lyn kinase controls Toll-like receptor signaling in a cell-specific, isoform-independent manner
No full textUniversity of Minnesota Ph.D. dissertation. September 2025. Major: Microbiology, Immunology and Cancer Biology. Advisor: Tanya Freedman. 1 computer file (PDF); xiii, 94 pages.Toll-like receptor (TLR) signaling is vital for antimicrobial macrophage function, and its dysregulation is associated with diseases such as lupus, multiple sclerosis, pulmonary fibrosis, and cancer. The Src-family kinase Lyn has net activating or inhibitory effects on TLR signaling, and the dominant role of Lyn downstream of TLRs differs by cell type. However, distinct functions of Lyn splice variants, LynA and LynB, in TLR signaling had not been investigated. I used isoform-specific Lyn knockout mice (LynAKO and LynBKO) to interrogate the contribution of each isoform to TLR signaling in bone-marrow-derived macrophages and splenic dendritic cells (DCs). Bulk RNA sequencing and cytokine analyses in macrophages revealed that complete Lyn deficiency (LynKO) dampened TLR4- and TLR7-induced expression of inflammatory genes and production of tumor necrosis factor (TNF) but enhanced the expression of genes responsible for synthesizing the extracellular matrix and promoting proliferation. Despite reduced expression of total Lyn in single-isoform LynKO BMDMs, expression of either LynA or LynB alone was sufficient to preserve a wild-type-like transcriptome at steady state and after treatment with the TLR7 agonist R848. However, LynAKO and LynBKO macrophages did have impaired TNF production in response to the TLR4 agonist lipopolysaccharide. Additionally, LynAKO and LynBKO macrophages were as hyperproliferative as LynKO cells. In contrast to macrophages, LynKO DCs produced more TNF in response to TLR4 and TLR7 stimulation. However, the expression of either LynA or LynB was sufficient to preserve WT-like TNF responses to TLR agonists in DCs. These data suggest that Lyn promotes macrophage activation in response to TLR signaling and restrains aberrant proliferation and matrix deposition in a dose-dependent rather than isoform-specific manner. These data also suggest that Lyn inhibits TLR signaling in DCs in an isoform-independent manner.Lindstedt, Anders. (2025). Lyn kinase controls Toll-like receptor signaling in a cell-specific, isoform-independent manner. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278792
Utilizing transition-metal catalysis for the development of novel aliphatic polyesters from bio-derived and waste feedstocks
No full textUniversity of Minnesota Ph.D. dissertation. June 2025. Major: Chemistry. Advisor: Ian Tonks. 1 computer file (PDF); xviii, 202 pages.Polyesters have emerged as an attractive alternative to industrial olefins due to their multiple end-of-life options and potential to be derived from biomass and waste feedstocks. This thesis will focus on investigating new degradable polyester synthesis via two methods: hydroesterification and ring-opening polymerization. Chapter 2 aims to expand the applications of hydroesterificative polymerization by first tuning polymer microstructure through catalyst design and then increasing the hydroesterification monomer library by a two-step carbonylation and condensation approach. Chapter 3 describes the synthesis and ring opening polymerization of lactones derived from isoprene, 1,3-butadiene, and CO2. Copolymers with varying ratios of isoprene incorporation were isolated and characterized. Through stepwise synthesis and individual reactivity studies, the inhibitory effect of one lactone was identified. Finally, chapter 4 investigates copolymerizations of CO2 and butadiene derived δ-lactones with commercially available lactones, L-lactide and ε-caprolactone. Based on monomer feed ratios and the type of addition employed, a wide range of polymer thermal and mechanical properties were achieved, thus expanding the potential applications of CO2-derived polyesters.Anderson, Ryan. (2025). Utilizing transition-metal catalysis for the development of novel aliphatic polyesters from bio-derived and waste feedstocks. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278191
Effectiveness and producers perceptions of camera-based technology detecting hoof lesions in dairy cows
No full textUniversity of Minnesota Ph.D. dissertation. July 2025. Major: Veterinary Medicine. Advisor: Gerard Cramer. 1 computer file (PDF); iii, 349 pages.Lameness remains a significant concern in the dairy industry, with growing interest in automated technologies for early detection and intervention. This dissertation combines quantitative, qualitative, and machine learning approaches to assess both the technical performance of an autonomous camera system and stakeholder perspectives on technology implementation. The first objective of this thesis was to evaluate how previous research has applied machine learning methods for detecting lameness and hoof lesions in dairy cattle (Chapter 1). The second and third objectives assessed the performance of an automated camera-based system that scores locomotion and body condition. Chapter 2 examined whether the system's locomotion scores were associated with hoof lesion outcomes, using hoof trimming data to compare cows with and without lesions. Chapter 3 evaluated the system’s ability to reliably identify individual cows. Chapter 4 assessed inter- and intra-observer reliability across different methods of body condition scoring, including human observers, photo-based scoring, and the automated system. Recognizing the role of human perspectives in technology adoption, Chapters 5 and 6 explored perceptions of lameness and lameness detection technologies among dairy farm decision-makers. These chapters focused on stakeholders view lameness management priorities and barriers to adopting automated technologies. Finally, Chapter 7 evaluated existing locomotion score-based thresholds for identifying cows with hoof lesions, while Chapter 8 developed a machine learning algorithm to improve classification of cows requiring intervention for hoof lesions. Together, these chapters contribute to advancing both the technical capabilities and real-world applicability of autonomous lameness detection technologies in the dairy industry.Swartz, Drew. (2025). Effectiveness and producers perceptions of camera-based technology detecting hoof lesions in dairy cows. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/278093