Now showing items 1-20 of 15506

    • The Effect of Colonic SCFA on Energy Homeostasis

      Duca, Frank A.; Powell, William Howard; Teske, Jennifer A.; Cai, Haijiang (The University of Arizona., 2022)
      Fiber consumption is negatively associated with body weight in humans and fiber supplementation improves energy homeostasis, due in part to the gut microbiome. Bacteria in the distal intestine ferment fiber into short chain fatty acids (SCFAs). We recently demonstrated that obesity is associated with decreased postprandial levels of distal intestine SCFAs; however, the impact of endogenous SCFAs on energy homeostasis is still unknown. Exogenous SCFAs improve energy homeostasis, an effect partly mediated by free fatty acid receptors (FFAR2 and FFAR3) located on enteroendocrine cells and neurons. However, studies outlining the suppressive effects of exogenous SCFAs on food intake often target the small intestine or circulation rather than replicating an increase in endogenous production in the distal intestine. To address this, we equipped male Sprague Dawley rats with proximal colon catheters and, following recovery, administered 200mM acetate, butyrate, propionate or saline at a rate of 0.15mL/min for 15min after a 12hr overnight fast. Rats were then returned to metabolic cages for 24hrs to assess food intake, energy expenditure, RER, and activity. SCFA infusions were bracketed by saline infusions and given every other day. All three SCFAs significantly suppressed food intake 1 and 12hrs post-infusion compared to saline, with no effect on energy expenditure (n=6-8). None of the acute SCFA administrations significantly impacted food intake, energy expenditure, or RER 24hrs post-infusion. To address the ability of SCFA administration to regulate energy homeostasis over a longer period of time, we infused acetate, propionate, butyrate or saline daily in a SCFA or control group. We found that only butyrate reduced cumulative intake compared to control and there were no other changes between SCFA and control treatments. Taken together, these data show that acute exogenous administration of acetate, propionate, or butyrate to the distal intestine suppresses food intake up to 12hrs post-infusion, potentially through similar mechanisms, but this effect is not replicated in a chronic daily infusion study for acetate or propionate.
    • Teaching Core Subjects and Traditional Food Knowledge Through Farm-to-School (F2S) Curriculum: The Usability and Cultural Relevance of Garden Lessons Serving Diné Youth at an Off-Grid Charter School in Leupp, Arizona

      Franklin, Edward; Rybin, Jaclyn; Shirley, Valerie; Chief, Karletta (The University of Arizona., 2022)
      The urgency for culturally relevant, decolonizing, and Indigenizing farm-to-school (F2S) educational offerings is prevalent in a Western-dominated educational system in the United States. This participant-oriented curriculum evaluation case study aimed to determine how primary school teachers at a primarily Diné (Navajo) serving charter school may incorporate and utilize the Service to All Relations (STAR) School Garden Lessons (SSGL) into their existing core subject curriculum and in teaching Diné culture, language, and traditions. The purpose of this study was to determine how elementary teachers at a Diné serving charter school may utilize and incorporate the SSGL into their existing curricula offerings teaching core subjects (i.e. Mathematics, Science, Diné/English Language, English Language Arts, and/or Social Studies) and Diné culture, traditions, and language around traditional foods. This qualitative case study aimed to gather teachers’ insights via an online survey instrument and optional follow-up interview(s) about the useability and cultural relevance of current F2S curriculum offerings via the SSGL. STAR school classroom teachers' beliefs and perceptions of current F2S curriculum offerings at the STAR school were collected to provide community-centered support and recommendations to enhance the usability of pre-existing SSGL offerings. Furthermore, the goal of this curriculum evaluation case study was to identify ways to improve F2S curriculum useability in teaching core subjects and to improve cultural relevance of SSGLs for teachers’ use in the classroom. The findings of this study were significant in identifying six (6) classroom teacher’s ideas for integration of core subjects and Diné culture, tradition, and language into SSGL, need for continuing cultural-competency training among non-Diné educators, and further work needed in decolonizing and Indigenizing current SSGL curriculum offerings. Future participant-led qualitative studies are recommended to help provide school administrators with more diverse feedback and insights from teachers on delivering culturally relevant F2S curriculum.
    • 4D Digital Breast Phantom for Contrast-Enhanced Imaging

      Clarkson, Eric W.; Li, Dan; Glick, Stephen J.; Kupinski, Matthew A. (The University of Arizona., 2022)
      A fully simulated 4D digital breast phantom model is developed inthis work. The model is based on an anthropomorphic digital breast 3D phantom, which gives the user better control of the 4D phan- tom features when it comes to developing and optimizing contrast enhancement imaging techniques. The fourth dimension of the phan- tom features different time-varying enhancement patterns for differ- ent materials including fibro glandular tissue and mass tissue. Phys- iological parameters that capture the key characteristics of different types of masses, for example, wash-in and wash-=out rates indicating metabolism level, are employed in the model to simulate certain fun- damental features for categorizing mass types. A two-compartment model, a well-known model in the field of Pharmacokinetics, is used to depict the diffusion process of the contrast agent. Two methods are proposed to allow the simulation of the necrotic core with varying shapes. To explore the benefit of the 4D phantom, digital mammograms are simulated and studied by the Monte Carlo method. To perform the simulation, the contrast agent blood tissue mixture’s cross-section pa- rameters are generated by linear interpolation between the parameters of blood, contrast agent, and tissue (mass or fibro glandular tissue). With the contrast agent in the tissue, higher contrast is achieved be- tween fibro glandular tissue and mass tissue. The contrast is then further enhanced by the log scale subtraction between high and low- energy mammograms.
    • A Design of a Solar-Powered Vertical Farm in Khartoum, Sudan

      Cuello, Joel; Taha, Najwan; Farrell-Poe, Kitt; Waller, Peter (The University of Arizona., 2022)
      Rising population, growing urbanization, diminishing fresh water supply, and climate change have been contributing to the planet’s deteriorating stocks of arable land. Intensive crop production in urban areas through vertical farming is considered a promising solution to help meet the increased demand for food in cities using non-arable land and in a more local and environmentally sustainable manner. In this study, we examined vertical farming as a potential solution to addressing the significant food insecurity in Sudan, Africa. Three types of vertical farms, each equipped with solar photovoltaics, were considered, namely: (1) warehouse vertical farm; (2) modular (shipping-container) vertical farm; and (3) greenhouse vertical farm. The specific objectives of the study were: (1) To design an appropriate embodiment for each of the three types of vertical farm as powered by solar photovoltaics to meet the annual demand for 66,000 kg of Yellow Potato and 79,200 heads of Rocket Arugula by the local grocery store Al-Anfal Supermarket in Sudan’s capital city of Khartoum; and (2) To assess the economic viability of each designed vertical farm embodiment as a business enterprise in Khartoum, Sudan. The conclusions of the study were as follows: (1) The greenhouse vertical farm was the most profitable case with a break-even period of 1.1 years and an estimated annual profit of $179,447; (2) The warehouse vertical farm was the second most profitable case with a break-even period of 1.3 years and an estimated annual profit of $166,924; (3) The modular shipping-container vertical farm was the last place with an estimated annual profit of $164,691 and breakeven point of 1.3 years; and, (4) Although requiring significant capital and operational investments, the foregoing three embodiments of vertical farming, powered by solar photovoltaics, to meet the annual demands for 66,000 kg of Yellow Potato and 79,200 heads of Rocket Arugula by the local grocery store Al-Anfal Supermarket in Sudan’s capital city of Khartoum, demonstrated reasonable promise for economic profitability.
    • Greek Pre-Colonial Contacts: Contextualizing the Movements of the Euboeans Overseas in The Early 8th Century BCE

      Hasaki, Eleni; Ramirez, River Roland; Romano, David G; Blake, Emma; Serino, Marco (The University of Arizona., 2022)
      Studies on Greek colonization first came into clear focus shortly after World War II. Dunbabin’s 1948 overview of western Greek colonies, rooted in the literary evidence of the early historians Herodotus and Thucydides, was quickly bolstered by the archaeological evidence of Buchner’s discoveries at Pithekoussai in 1952. While scholarship on colonization from both a literary and archaeological perspective continued unabated in the ensuing decades of the 20th century, the discourse was largely dampened by a shift away from trends of migration in the larger post-processual framework of archaeological study. However, beginning in the 1990’s and early 2000’s from advancements and the acceptance of techniques in digital archaeology and archaeometry, mobility studies have dramatically increased in popularity. In the Greek case, this has resulted in the term ‘colonization’ itself coming under fire. This is indicative of the divide between scholars who still largely follow the normative model of Greek colonization, on the one hand, versus those who embrace the new terminology of “mobility” and its entailment of wider interactions in which the unilateral Greek colonization-as-foundation framework is called into question. This thesis follows along with the more recent trend in scholarship by attempting to contextualize the earliest movements of the Greeks, specifically the Euboeans, in the west in the century before the first known act of ktisis (i.e. Pithekoussai around 750 BCE). The aim is largely to bridge the gap between disparate and insulated fields of scholarship in order to construct a coherent historical narrative diachronically and regionally framing the pre-colonial period (the early ninth to late eighth century BCE). Throughout, the primacy of the Euboean “colonizer” as an instigator of interaction is challenged, first by examining the possibility of continuity between Bronze Age and Early Iron Age networks to the west, as well as by setting the Greek endeavors within a more globalized Mediterranean world of Phoenician mobility. Finally, the materiality of cross-cultural interactions is considered by examining the archaeological finds, largely of Euboean Middle Geometric II skyphoi, which attest to dynamic elite relationships leading to colonialism.
    • Impacts of Artificial Warming on Vegetation and Soil Fungal Communities in Two Sites in the Cruz-Verde Sumapaz Paramo Complex, Colombia

      U'Ren, Jana; Schlottman, Bradley Aaron; Barberán, Albert AB; Hurwitz, Bonnie BH (The University of Arizona., 2022)
      Background: Similar to its impact on high latitude boreal and arctic ecosystems, climate change is predicted to also alter high-elevation ecosystems such as páramos: Andes alpine ecosystems that contain vast water and soil carbon reservoirs that harbor up to six times more soil carbon compared with surrounding lowlands. In particular, warming temperatures due to climate change are predicted to accelerate the release of stored carbon from soils to the atmosphere via microbial respiration, yet to date few studies have examined the impact of warming on páramos vegetation, soil properties, and soil microbial communities. Methods: As part of a larger study examining the impact of artificial warming in two páramo sites in Colombia (Sumapaz and Matarrendonda), this study re-analyzed two years of vegetation and soil survey data in conjunction with Illumina ITS nrDNA amplicon sequencing of soil fungal communities to assess (i) the impact of the warming treatment on the richness and composition of plant, lichen, and soil fungal communities, as well as on edaphic parameters in each site; (ii) differences in biotic and abiotic factors between sites; and (iii) how biotic and abiotic factors in both sites changed over the period of the experiment (2016-2018). Comparisons accounted for the non-independence of experimentally warmed and control plots in each sampling block using paired t-tests. Results: Paired t-tests of warming treatment vs. control plots revealed that experimental warming did not significantly alter per plot soil properties, air temperature, or vegetation or soil fungal richness in either site. The two sites had different plant and lichen richness and composition, as well as climate and soil properties: Matarrendonda is characterized by warmer temperatures and increased precipitation compared to Sumapaz, as well higher soil gravimetric water content and plant and lichen richness at both the species and family levels. However, in both sites no correlations were observed between vegetation or fungal species richness with soil properties or temperature in 2016 or 2018. Despite differences in fungal soil community richness between sites, communities in both sites had similar phylum and species-level composition. From 2016 to 2018, plant and lichens richness, as well as soil bulk density and gravimetric water content increased in both sites. In Matarrendonda, increased vegetation richness was positively associated with changes in pH and negatively associated with changes in gravimetric water content over time. Mean soil fungal richness decreased over time in Sumapaz, but not Matarrendonda. The composition of fungal communities changed over time, associated with increased differences in soil properties between sites. Discussion. Here, we found that experimental warming treatment had little impact on biotic or abiotic properties when paired treatment and control plots were compared. Although fiberglass open-top chambers have previously been used to artificially increase soil warming, previous studies also have noted few effects on vegetation or soil microbial communities in the first years following their implementation. Here, despite no impact of warming we found that over the two-year period both sites experienced increases in plant and lichen species and family-level richness, as well as altered soil properties and more distinct fungal communities. Overall, additional studies are needed to address changes in the function of páramo vegetation and soil fungal communities over longer time periods, as changes in certain groups of soil communities may severely impact carbon cycling in these important ecosystems.
    • The Influence of Gender Inequities Experienced on the Intended Career Pathways of Women Veterinary Students

      Mars, Matthew; Kimble, Natalie; Rice, Amber; Torres, Robert (The University of Arizona., 2022)
      This study is focused on women veterinary medicine students and how misogyny and sexism have influenced their career pathways. The concept of rapid feminization of veterinary medicine was assessed as the effects can be seen industry-wide (i.e.- a downward trend in salaries, loss of large animal veterinarians, and loss of rural veterinarians). The gender inequities that women veterinary medicine students face were explored in order to determine why these trends could exist. Women students at Southwestern University College of Veterinary Medicine were interviewed and the findings revealed a double-sided coin of misogyny and sexism. On the surface, there is a fairly progressive environment being created as the students continuously felt as though their gender did not play a role in their education, creating a relatively agendered experience. However, the school was replicating a misogynistic cycle of pushing a women-majority class into women-majority fields (i.e.- small animal medicine or general medicine) through a disproportionate curriculum.
    • Pro-Longevity Kynurenine Pathway Interventions Modulate Mitochondrial Dynamics in C. elegans

      Sutphin, George L.; Meyers, Jeremy Blake; Buchan, Ross; Maggert, Keith (The University of Arizona., 2022)
      Aging is a conserved phenomenon that affects many eukaryotic systems. Aging can be defined as the gradual, chronic loss of function in many biological processes that ultimately lead to the death of an organism. Mitochondria are entangled in the aging paradigm in eukaryotic systems. In healthy organisms, mitochondria are a dynamic network of membrane bound organelles that generate the cell’s preferred potential energy source, ATP. Mitochondrial dysfunction is one of the nine hallmarks of aging (1). Mitochondrial dysfunction impacts the other eight hallmarks of aging either directly or indirectly (2). The dynamic structure of mitochondria, i.e., the degree of interconnectedness or fragmentation of the mitochondrial network, is regulated by the two opposing processes of mitochondrial fission and fusion. Mitochondrial fission occurs when there is an excess of nutrients or oxidative stress and results in spherical, fragmented mitochondrial networks. Fusion occurs under caloric restriction, a known pro-longevity intervention, and results in elongated, tubular mitochondrial networks. The kynurenine pathway is the de novo synthesis pathway of nicotinamide adenine dinucleotide (NAD+) from exogenous tryptophan. Impairing the activity of the kynurenine pathway enzymes 3-hydroxyanthranilic acid (HAAO) and kynureninase (KYNU) increases lifespan in Caenorhabditis elegans by 20-30%. Adding exogenous 3-hydroxyanthranilic acid (3HAA), the metabolite generated by KYNU and degraded by HAAO, increases lifespan to a similar degree to knocking out HAAO inhibition. Mitochondrial function and the kynurenine pathway are connected by NAD+ as it is a product of the kynurenine pathway and used as an electron carrier for the electron transport chain in the mitochondria. Mitochondrial function and structure have not previously been characterized in the context of pro-longevity kynurenine pathway interventions. In this work I examine mitochondrial function and structure when subjected to kynurenine pathway inhibition. Kynurenine pathway modulation results in slight mitochondrial dysfunction middle in life as measured by O2 consumption assays. Mitochondrial fragmentation is observed when C. elegans are treated with kynurenine pathway modulation. This work should establish a link between kynurenine pathway inhibition and mitochondrial function in the context of aging.
    • Mʉ̃tẽã Documentation Project: Grammatical Lessons for Language Teachers and Students

      de Lima Silva, Wilson; Barraza, Oliver; Zepeda, Ofelia; Fountain, Amy (The University of Arizona., 2022)
      This thesis is part of a continuous documentation project directly requested by a Tukanoan language community called the Mʉ̃tẽã, located in the Vaupés region of Colombia. The purpose of this paper is to create lessons that can be translated and brought back to the community. The use of these lessons will be to explain the linguistic background of Mʉ̃tẽã in a way that allows teachers and students to generate their own examples per term. Lessons within this paper will be translated into Spanish, the conduit language of this group, and taught within workshops. For these reasons, the paper is written from a pedological approach rather than the format usually intended for academic linguistic audiences. This group of individuals in the workshops have exhibited enormous efforts in preserving their language, and the request for this kind of material shows their ongoing desire to do everything they can in revitalizing Mʉ̃tẽã. Within this paper, sample sentences and examples displayed within the lessons are derived from the field notes taken down by Dr. Wilson De Lima Silva and the Vargas-Acosta-Correa family. As the examples are listed, the corresponding word from the dictionary will be written directly beneath the sample with any other important identifying features. Besides the dictionary sentences, examples will also be drawn from the folk story The Creation of the Moon, as a story often lends itself to some of the more unique and specialized aspects displayed in the language. Each of those will also be labeled with according glossing number from DiRadio-Owens' thesis analysis.
    • Diagnosis of Intrauterine Inflammation/Infection in Women with Preterm Prelabor Rupture of Membranes Using Cervicovaginal Interleukin-6 Concentrations: Systematic Review and Meta-Analysis

      Cook, Curtis; Herbst-Kralovetz, Melissa; Gomez, Daniela; Hammer, Ronald; Huls, Christopher (The University of Arizona., 2022)
      Title: Diagnosis of intrauterine inflammation/infection in women with preterm prelabor rupture of membranes using cervicovaginal interleukin-6 concentrations: systematic review and meta-analysis Objective: To establish the diagnostic test accuracy of cervicovaginal interleukin-6 concentration in the detection of intraamniotic inflammation, in women with preterm prelabor rupture of membranes (PPROM) at less than 37 weeks of gestational age. Data sources: A systematic literature search was undertaken using Embase, SCOPUS, PubMed, and the Cochrane library from their inception to Feb 2022. Study eligibility criteria: Prospective and retrospective studies evaluating cervicovaginal interleukin-6 (IL-6) concentrations, in women diagnosed with PPROM at less than 37weeks of gestation, were included. Study appraisal and synthesis methods: Cervicovaginal IL-6 concentration was assessed as the index test for the prediction of intraamniotic inflammation. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was independently used by two reviewers to assess the quality of the studies. Forest plots for sensitivity and specificity with 95% CIs were constructed. Hierarchical summary receiver operating characteristic curves were constructed; quantitative data synthesis was performed using random-effects models. Diagnostic odds ratios were calculated to measure the global effectiveness of the diagnostic test. Heterogeneity was assessed using Cochran’s Q statistic, with p <0.10 denoting heterogeneity. Meta-regression was performed to assess the effect of 2 covariates. Publication bias could not be assessed given the limited number of studies. Results: Eighteen studies were retained for qualitative analysis, 14 were included in the meta-analysis. The study population included 1,655 women diagnosed with PPROM. According to the QUADAS-2 tool, all included studies were of poor quality. The area under the curve (AUC) for the diagnosis of intraamniotic inflammation and/or infection by cervicovaginal IL-6 was 0.838  0.035. The pooled diagnostic odds ratio of cervicovaginal IL-6 was found to be 10.74 (95% CI 5.45, 21.17). Based on the Cochran’s Q value of 88.03 (p = 0.00), a high degree of heterogeneity exists across studies. Conclusions: Cervicovaginal IL-6 has a DOR of 10.74 (95% CI 5.45, 21.17) in the detection of intrauterine inflammation/infection. Based on our results, cervicovaginal IL-6 seems to have a good diagnostic accuracy in the detection of intraamniotic inflammation/infection in women with PPROM.
    • Experiences of Recently Graduated Women School Based Agricultural Education Students in Arizona: A Critical Feminist Approach

      Rice, Amber H.; Donaldson, Angus J.; Mars, Matthew M.; Molina, Quintin (The University of Arizona., 2022)
      School based agricultural education (SBAE) works to grow high school students’ leadership abilities and likelihood for success in agriculture careers. Past research found inequalities between the experiences of women and men students in SBAE and currently there is a paucity of research investigating the experiences of women students in Arizona SBAE programs. The central research question that guided this study was: What are the experiences of recent women graduates of SBAE programs in Arizona? This research was conducted utilizing critical feminist theory and used Acker’s theory of gendered organizations as its theoretical framework. Data was collected through interviews with fifteen recent women graduates from Arizona SBAE programs. Five themes emerged from the data: 1) Advisors perpetuate the Culture of SBAE in Their Programs, 2) Differing Expectations Exist Between Women and Men Students in SBAE, 3) Enforcement of FFA Official Dress Disproportionately Affects Women Students, 4) Gendered Interactions with Advisors, Peers, and the Community, and 5) Women Not Seen in the Same Spaces as Men Within the Agriculture Industry. It is recommended that further research explore the experiences of other women students in SBAE, women students who left SBAE early, SBAE students that do not identify as cis gendered, and how the expectations placed upon women and men students affect their experiences in SBAE. Recommendations for practice include encouraging the updated FFA official dress rules allowing any student to wear slacks or a skirt, refraining from setting expectations based on gender, and increase representation of women throughout the agriculture industry.
    • Metabolic Alterations in Colorectal Cancer Progression

      Snider, Ashley J.; Smith, Beatriz; Duca, Frank A.; Snider, Justin M.; Ghishan, Fayez K. (The University of Arizona., 2022)
      Human colorectal cancer is the progressive accumulation of mutations that occur in the epithelial lining of the digestive tract. One-third of patients diagnosed with colorectal cancers are hereditary or familiar cancers, while the other two-thirds of patients are diagnosed with sporadic colorectal cancer. Human colon epithelial cell lines were generated from human colon epithelium and immortalized with overexpression of CDK4 and hTERT (HCEC 1CT). Subsequent cell lines were developed to model the mutations that occur in sporadic colon cancer; CTA cells have deletion of APC, an essential protein in the WNT pathway, representative of early adenoma; RPA cells mimic late-stage adenoma and are deficient in APC and P53 and overexpress mutant KRas; A1309 cells were developed via the addition of truncated APC in the RPA cell line. All four HCEC cell lines were analyzed for metabolomic and lipidomic alterations. PCA and PLS-DA analyses of untargeted lipidomics demonstrated all lines cluster independently from one another. Heatmap analysis of the top 100 most significant lipids (p-value <0.05) showed RPA and A1309 cell lines to have the most distinct lipid profiles. Therefore, RPA and A1309 were analyzed further. Volcano plots and deconstructed volcano plots demonstrated significant alterations in specific lipid classes. Pathway analysis of the altered lipids established glycerophospholipids and sphingolipids as the lipid classes with the most significant alterations. Quantitative analyses of sphingolipids revealed significant differences in ceramides and hexosylceramides between RPA and A1309 cells. These data suggest that truncation of APC alter sphingolipid metabolism. Future studies will examine the roles of ceramides and hexosylceramides in cancer cell biologies including migration, proliferation, viability, and cell cycle.
    • Amplification of Enterocytozoon hepatopenaei in Penaeus vannamei Hepatopancreas Primary Culture and Immunofluorescence Assay for Detection of Enterocytozoon hepatopenaei

      Viswanathan, V.K.; Cho, Sungman; Dhar, Arun K.; Riggs, Michael; McCarthy, Fiona W.; Fitzsimmons, Kevin M. (The University of Arizona., 2022)
      Hepatopancreatic microsporidiosis (HPM) disease leads to retarded growth in shrimp resulting in a major loss for the shrimp industry worldwide. The causative agent of HPM is a microsporidian known as Enterocytozoon hepatopenaei (EHP). It is little understood how EHP infects its host and hijacks its cellular machinery to replicate more organisms. Lack of an immortal cell line is a bottleneck in studying the cellular and molecular basis of EHP infection in shrimp. For this reason, EHP cannot be propagated in in vitro culture and must be propagated in live shrimp. The use of live EHP-infected shrimp remains the only way to study EHP infectivity. It was hypothesized that supplementing EHP with fresh host cells will aid the propagation of EHP in vitro. Further research must be done but with the data collected at this point, this hypothesis is rejected. In addition to the challenges in amplifying EHP in in vitro culture, there is no antibody-based detection method for EHP. EHP infection in a shrimp is examined by Hematoxylin and Eosin (H&E) histology and real-time polymerase chain reaction based detection methods. Monoclonal antibodies that were previously characterized by Riggs and colleagues to detect Cryptosporidium parvum (C. parvum), successfully detected other parasites. Based on this, it was hypothesized that monoclonal antibodies against C. parvum may also detect EHP.
    • Germination Response of Twelve Accessions of Bouteloua curtipendula (Michx.) Torr. (Poaceae) to a Simulated Winter Temperature Regime

      Fehmi, Jeffrey S.; Philabaum, Wyatt Thomas; Smith, Steven E.; Gornish, Elise S. (The University of Arizona., 2022)
      Twelve accessions of Bouteloua curtipendula were tested in a laboratory growth chamber to examine the effect of simulated winter temperature on the germination response of the selected accessions of B. curtipendula var. curtipendula (Michx.) Torr. and B. curtipendula var. caespitosa Gould & Kapadia, two botanical varieties of disparate origin. Accessions of the variety curtipendula had significantly higher total germination percentages compared to accessions whose variety was var. caespitosa under the winter treatment. Latitude was also significant with accessions whose origin was farther north exhibiting higher relative germination percentages under the winter treatment. Mean total germination percentage was significantly higher for accessions whose grains were from NPGS seed production facilities under the winter treatment compared to the mean of accessions from wild-collected populations. Mean seed (grain) mass was highly correlated (rs = 0.774) with relative germination percentages, suggesting seed vigor may be an important explanatory factor in germination under stressful conditions.
    • A Drosophila Model of Frontotemporal Dementia (FTD) Based on C9ORF72 Hexanucleotide Repeat Expansion

      Zarnescu, Daniela; Williams, Christi; Tax, Frans; Sutphin, George (The University of Arizona., 2022)
      Frontotemporal dementia (FTD) is a neurodegenerative disorder characterized by a spectrum of symptoms such as loss of intellectual functions, including memory problems, impaired reasoning, abstract thinking, executive function, that can severely impact daily living activities. Frontotemporal lobar degeneration (FTDL) leads to a diverse group of conditions that are hallmarked by atrophy in the prefrontal and anterior temporal cortices. FTD is substantially less common than Alzheimer’s disease, but still greatly impacts individual lives leading to high socioeconomic costs to treat. This specialized level of care is valued at $244 billion, but its costs extend to the family caregivers’ who have an increased risk for emotional distress and negative physical and mental outcomes. Additionally, the overall incidence of cases of FTD is expected to increase, as our aging population is expected to grow by 2030 to include 1 in 5 Americans 65 years old and over. Approximately, 43% of FTD patients have a family history related to dementia or associated neurodegenerative diseases, with up to 27% of individuals carrying an autosomal dominant mutation. When examining the subsets of familial FTD cases, mutations in three genes, microtubule-associated protein tau (MAPT), progranulin (GRN), and C9orf72, are prominent. The overarching hypothesis for this project is that overexpression of C9orf72 hexanucleotide repeat expansions (HREs) in RNA and/or dipeptide repeats (DPRs) in the encoded proteins in mushroom body neurons cause FTD like phenotypes in Drosophila. The present findings in this study show that overexpression of C9orf72 hexanucleotide repeat expansions (HREs) and DPRs in Drosophila MBs causes FTD like phenotypes. Sleep studies revealed that young flies expressing RNA only HREs exhibited greater sleepiness, while polyGR DPR flies displayed sleep changes later in their lifespan. Old (60 day) RNA only HRE expressing males showed sleep fragmentation while female flies exhibited greater sleepiness. Y-Maze assays uncovered that both RNA only HREs and polyGR DPRs caused increased locomotion rather than working memory deficits, as expected. This finding indicates possible hyperactivity in C9orf72 hexanucleotide repeat expansion flies through an increase in movement at both young and old age points. Morphological studies showed a profound, age dependent axonal thinning. In summary, this study shows that both C9orf72 HRE and DPR expressing flies exhibit sleep dysregulation, hyperactivity, and MB lobe thinning changes that could be examined closer to determine the underlying mechanisms of disease and provide further information on the genetic pathways and cellular mechanisms behind C9orf72 induced FTD.
    • Optomechanics as a Probe for New Physics: From Dark Matter to Spontaneous Wave Function Collapse

      Wilson, Dalziel J.; Pandurangi, Utkal; Mansuripur, Masud; Wright, Ewan M. (The University of Arizona., 2022)
      Optomechanical systems can be used to probe weak forces arising from fundamental physical phenomena. Here, we analyze experimental efforts to search for ultralight dark matter and test spontaneous wave function collapse models, using ultra-low-loss micromechanical resonators based on silicon nitride membranes. We predict that constraints can be drawn in room temperature, table-top experiments that are competitive with the contemporary bounds set by large-scale experiments such as the Laser Interferometer Gravitational-Wave Observatory. In the future, we envision setting more stringent bounds by operating experiments in a cryostat.
    • Bandages and Plasters as Wound Care In Greco-Roman Antiquity: A Review of The Ancient Evidence and Experimental Analysis

      Hasaki, Eleni; Blanck, Allyson; Groves, Robert; Soren, David; Watson, James T. (The University of Arizona., 2022)
      This thesis project encompasses a comprehensive overview of visual, literary, and archaeological evidence concerning wound care in the ancient Greco-Roman world. Analysis of this evidence will explore medical themes such as the different types of medical responses to wounds available in antiquity, preparation of treatments, and the importance of instructionally minded prose in medical writing. I have approached wound care from an interdisciplinary perspective in order to develop a more nuanced understanding of treatment types associated with injury during these periods. The scope of this project is diachronic and considers the development of wound care (specifically the use of bandages and plasters) from the 5th century BCE to the 2nd century CE. Wound care can involve a range of treatments, but for this project I focus on bandages and plasters as the essential core of material technology which was used by Greco-Roman physicians to encourage wound healing. Currently, there are zero comprehensive studies of plaster as a unique classification of medical treatment. So, this thesis aims to begin approaching the topic in a comprehensive manner, placing it in association with wound care generally, and in contrast with the more well-known linen bandage. The second chapter begins this exploration by discussing visual evidence of bandages and injury as found in Greek and Roman art, to understand non-medical perspectives of wound care. Here, I argue that bandages can be used as a visual attribute for survival when representing important figures such as Patroclus, and, conversely, the lack of visable treatment represents a figure who will likely perish soon, or has already passed away. In the third chapter, I turn to the medical texts and explore how wound care treatments and recipes exist as instructional materials within the literature. Overall, this chapter further contributes to scholarly understanding of the instructional values, as described through the carefully crafted prose which encourages the dissemination of treatment methods and recipes to the reader. These chapters also explore how the Greco-Roman tradition of wound care expands from a much longer and generally Mediterranean medical tradition, derived in part from early Egyptian practices which directly inform the use of medical technology in the Greco-Roman world. This in turn has fundamentally structured our own modern approaches to injury and still informs the basic tenets of the wound care treatments we use every day. The remaining chapters are dedicated to exploring the logistics of ancient wound care using experimental archaeology techniques. Experimental analysis from these chapters explore how various versions of plaster treatments as described within the Hippocratic corpus, Celsus’ De Medicina, and other sources were created. This approach also shows how treatments written as recipes could be effectively recreated by the reader alone in most cases, and what types of common-sense knowledge might be required of the reader to do so successfully. I describe the sources and methodology used to re-create a few chosen plaster recipes known from antiquity, and present the results of each experiment in detail. These experiments were also undertaken in order to fully clarify what the ancient physician considered a plaster to be as a material product, and through this process I have developed a working definition for plaster treatments specifically. By forming these plaster type treatments in the modern day, it is possible to learn more about the limitations of their use, as well as how the treatments were categorized within medical thought. Discussion studies the variety of these treatments, as well as the common qualities and ingredients. Altogether, this approach confirms without a doubt that the medical treatises of Greco-Roman antiquity do have direct instructional value. The dissemination of knowledge through both medical and non-medical literature, as well as through art thus reflects the strength of these sources, and the relative importance they held in antiquity.
    • Demonstration of Curvature Polynomials for Determining the Zernike Coefficients from Wavefront Curvature Data

      Kim, Daewook; Guruprasad, Divya; Mahajan, Virendra N.; Acosta, Eva; Chalifoux, Brandon D. (The University of Arizona., 2022)
      We describe numerical simulations to demonstrate the use of curvature polynomials introduced by Mahajan and Acosta in their paper “Zernike coefficients from wavefront curvature data” for determining the Zernike coefficients from wavefront curvature data. The wavefront curvature data was determined by evaluating the irradiance distributions in two planes that were symmetric about the focal plane. The irradiance distributions were calculated using the Zemax OpticStudio software program.For the aberration function, the wavefront curvature data was generated from the irradiance distributions. This data consists of the Laplacian of the wavefront across the pupil and its outward normal slope at its circular boundary. The inner products of the curvature polynomials and Laplacian of the wavefront are used to calculate the m ≠ n (i.e., non-harmonic) Zernike aberration coefficients, and the inner product of the boundary slope and curvature polynomials are required to calculate the m = n (i.e., harmonic) Zernike aberration coefficients. We explain the process of obtaining the Laplacian and slope of the wavefront from the two irradiance distributions. Independent case studies of different simulations are performed and explained in detail. The results obtained and limitations of the software are also presented.
    • Control of the Laminar Separation Bubble on a Plunging Airfoil using Plasma Actuators

      Little, Jesse; Pande, Arth; Craig, Alex; Fasel, Hermann (The University of Arizona., 2022)
      The laminar separation bubble on an X-56A wing section is studied experimentally for static and heaving/plunging conditions at α=12° with Re=200,000 (U_∞=11 m/s), and compared with numerical simulations. Heaving/plunging motion perpendicular to the airfoil chord with k=0.70, and h=0.48% is applied. Bubble shedding dynamics from previous studies dictated these parameters. Active flow control (AFC) in the form of ac-DBD plasma actuation is employed in experiments for both static and plunging wing conditions to influence the laminar separation bubble. Flat-plate PIV data was used to characterize the actuator performance in quiescent conditions. The experimental data is compared to 2D slot blowing/suction in CFD. In both cases, the AFC is applied for 75% of the plunging cycle from 90°<φ<360° with St_c=52 (1600 Hz). The simulations used a blowing ratio B=5% while the experiments used B≈1%, resulting in estimates of C_μ=0.000580% and C_μ=0.000534%, respectively. AFC in dimensional frequencies of St_c=26,C_μ=0.000368% (800 Hz) and St_c=104,C_μ=0.000662% (3200 Hz) is also applied to characterize its effect. AFC eliminates the LSB and prevents “bursting” which occurs in the unforced oscillating case. AFC at St_c=52 (1600 Hz) is found to be the most effective, as predicted by CFD simulations. The efficacy of the AFC mechanism arises from the excitation of the primary shear layer instability over the bubble. This produces spanwise 2-dimensional coherent structures in experiments (St_c=52) for both static and plunging conditions. CFD simulations suggest that forcing at the primary shear layer instability can delay transition downstream of reattachment. Similar control authority is observed in experiments, but quantitative evidence for transition delay remains elusive.
    • Environmental Health Catalyst: Visualizing Soil Contamination and Bioavailability of Metal(Loid)S for Action with Communities

      Ramírez-Andreotta, Mónica; Trahan, Alexandra Stewart; Chief, Karletta; Root, Robert (The University of Arizona., 2022)
      Mining poses ecological and human health risks. The state of Arizona has naturally occurring metal(loid)s that can be concentrated and transported during mining activities. These activities can increase human exposure to the mined and processed metal(loid)s. Exposure to metal(loid)s such as arsenic (As), lead (Pb), manganese (Mn), and copper (Cu) are associated with cancer and noncancer outcomes. This work outlines a co-created community science process with the rural town of Superior, AZ, where the community is subject to potential environmental hazards from legacy, active, and proposed extraction activities. Gardenroots, a co-created community science environmental health project started in Superior, AZ in 2018. Community scientists and university researchers determined metal(loid) concentrations in drinking water, soil, and dust. After extensive data sharing efforts, participants began to question past remediation efforts and pose new research questions, e.g.: (1) What sites were remediated?; (2) What determined a site’s eligibility for remediation?; and (3) How can we protect families that are unknowingly moving into homes that may have contaminated soil?. Thus, to answer the community questions, Gardenroots efforts evolved and responded by: (a) maintaining community engagement, (b) identifying and consolidating past monitoring and remediation efforts in the area, (c) creating an interactive soil map that visualized As, Pb, Mn, and Cu concentrations in soil; and (c) determining site-specific Pb and As gastric bioavailability. The soil visualizations include soil data from pre- (126 property values) and post-smelter (17 property values) demolition. To determine the bioaccessible fraction (BAF) of Pb and As, In-Vitro Bioaccessibility Assays EPA Method 1340 was conducted using the Gardenroots residential soils. Our assay calculations indicate bioaccessible fraction for As (12%-53%) and Pb (3%-79%). To provide additional soil sampling and prompt further soil remediation efforts, we worked with local, state, and federal agencies to organize and hosted a Center for Disease Control – Agency for Toxic Substances and Disease Registry soilSHOP on June 4, 2022. At this soilSHOP, we provided soil screening and health education to the Superior, AZ region. Based on community reporting and media tracking, Gardenroots and the soilSHOP prompted further action by Broken Hill Proprietary (BHP) Copper, to continue with their Voluntary Remediation Program (VRP) being overseen by the Arizona Department of Environmental Quality. The VRP is designed to provide environmental monitoring and remediation in town. It is anticipated that the recent actions taken by BHP Copper and Resolution Copper are a result of the co-created community science and soilSHOP, both of which are designed to reduce information disparities and increase environmental health literacy.