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Improving Management and Understanding of Major Diseases of Sugar Beet
Get PDFSugar beet is a sugar-yielding crop, that contributes 25% of the global sucrose production. Economic production of sugar beet is hampered by Cercospora leaf spot (CLS) (Cercospora beticola), Rhizoctonia crown and root rot (RCRR) (Rhizoctonia solani), Sclerotinia root rot (SRR) (Sclerotinia sclerotiorum), and Rhizopus root rot (Rhizopus arrhizus) diseases. These diseases can reduce yield by 15 to 40%. On CLS, buildup of fungicide-resistance strains is a major issue due to poor implementation of fungicides and understanding of disease development at early stages. The identification of germplasm resistant to RCRR disease is hindered by the lack of effective inoculation methods. Identification of SRR and RRR pathogens is crucial for their proper management. The objectives of this research were 1. to evaluate the role of adjuvants in improving the efficacy of fungicides on CLS, 2. to characterize the infection process during early stages of infection by C. beticola, 3. to identify an effective inoculation method for RCRR, and 4. to identify and characterize the causal organisms of SSR and RRR. The value of adjuvants was evaluated in greenhouse and field conditions. Application of fungicides with or without adjuvants before disease onset reduced disease severity of CLS in greenhouse condition. In field conditions, additions of adjuvants did not improve the effectiveness of fungicides and few of them negatively impacted root yield. The initial stage of infection on CLS susceptible and resistant sugar beet variety were compared using confocal microscopy. C. beticola biomass accumulation, percent leaf cell death and disease severity were all significantly greater in the susceptible variety compared to the resistant variety (P<0.05). R. solani inoculated on the crown and roots were compared in a replicated trial in greenhouse conditions. The root inoculation method provided a more consistent disease rating of the sugar beet variety in the greenhouse for screening of RCRR cultivars in a resistance breeding program. Based on morphological and molecular techniques, causal organisms of SRR and RRR were characterized and was found to be pathogenic to sugar beet varieties tested in-vitro and in the greenhouse conditions
Enhancing Natural Capital to Improve Mental Health and Well-Being in Rural Communities in Minnesota
Get PDFThis paper explores how green space can aid in improved mental health outcomes for individuals who live in rural communities in greater Minnesota. The mental health landscape across the state is complex and layered, complicated by access, insurance, broadband, and employment. At the local level, built and natural policy have the ability to directly impact physical and mental health outcomes for people; positively or negatively. Unfortunately, little literature exists in rural context; shadowed by its urban counterpart. By exploring how broader partnerships and policy can be strengthened, local and county government play a critical role in how communities can support broader mental health interventions. This paper seeks to understand how design, policy, and programming solutions can center parks and green space into the broader conversation of health, and divert away from green space as a ?nice to have amenity,? and towards critical infrastructure
Genome Wide Association Study of Basic Fruit Chemistry in the Cold Climate Wine Grapes (Vitis spp.)
No full textTo overcome some of these challenges posed by ND climate, the utilization of native wild Vitis-derived varieties is the best possible option available. Despite advantageous environmental tolerances of native wild Vitis spp. derived crosses, their acid and sugar concentrations often deviate from expectations set for V. vinifera. Identifying the genetic determinants of titratable acidity (TA), pH, and total soluble solids (TSS/?Brix) in interspecific hybrid populations can help improve new hybrid cultivars. For this purpose, an incomplete diallel mapping population with substantial riparia and other wild Vitis spp. in its background was used to perform association studies. The population is genotyped with single nucleotide polymorphism (SNP) markers and phenotyped over two years. Genome wide association analysis (GWAS) identified a significant association on chromosomes 6 and 16 for all three traits in both years. Candidate gene identification under the significant region revealed multiple glucose, fructose, and amino acid metabolism genes
Predictive Reliability Analysis and Maintenance Planning of Complex Systems Working under Dynamic Operating Conditions
Get PDFPredictive analytics has multiple facets that range from failure predictability and optimal asset management to high-level managerial insights. Predicting the failure time of assets and estimating their reliability through efficient prognostics and reliability assessment framework allow for appropriate maintenance actions to avoid catastrophic failures and reduce maintenance costs. Most of the systems used in the manufacturing and service sectors are composed of multiple interdependent components. Moreover, these systems experience dynamic operating conditions during their life. The dynamic operating conditions and the system complexity pose three challenging questions: how to perform the prognostic and reliability assessment of a complex multi-component system, how to perform the prognostic and reliability assessment of a system functioning under dynamic operating conditions, and how to use the condition based and reliability assessment data to find the optimal maintenance strategy for complex systems. This dissertation investigates five tasks to address these challenges. (1) To capture the stochastic dependency between interdependent components of a system through a continuous time Markov process with the transition rate depending on the state of all components of the system. This technique helps get an accurate estimation of system reliability. (2) To propose a framework based on instance-based learning to predict the remaining useful life (RUL) of a complex system. This technique can be used for highly complex systems with no need of having prior expertise on the system behavior. (3) To incorporate time-varying operating conditions in the prognostics framework through a proportional hazards model with external covariates dependent on the operating condition and internal covariates dependent on the degradation state of the system. (4) To propose a prognostic framework based on deep learning to predict the RUL of a system working in dynamic operating conditions. This framework has two main steps: first identifying the degrading point and developing the Long Short-Term Memory model to predict the RUL. (5) To propose an efficient algorithm for reliability analysis of a phased-mission system, its behavior changes at different phases during the mission. This technique accounts for imperfect fault coverage for the components to get accurate reliability analysis
Apelin-APJ Signaling in Hypertensive Coronary Arteries
Get PDFApelin is an endogenous ligand for APJ receptors, which are highly expressed throughout
the cardiovascular system, including coronary arteries. Apelin causes endothelium?derived nitric
oxide (NO) ?dependent relaxation of coronary arteries under physiological conditions, but little is
known about regulation of coronary vasomotor tone by apelin under pathological conditions. This
research addresses the critical gap in understanding of the apelin signaling in coronary circulation
under normal and pathological conditions.
Evidence from this study suggests that apelin could not provide beneficial vasodilatory
effects in hypertensive coronary arteries. Moreover, apelin impairs endothelium-dependent
relaxations to vasodilator, acetylcholine. Impaired apelin-APJ signaling in hypertensive coronary
arteries is possibly through defective production or release of NO from coronary endothelial cells
rather than inhibiting effects of NO in coronary arterial smooth muscle cells.
My next aim was to understand the mechanisms involved in the loss of apelin response in
hypertensive arteries. The results suggested that the APJ receptor signaling via GRK2 pathway is
possibly responsible for the impaired apelin response in hypertensive coronary arteries.
Interestingly, APJ receptor biased agonist, CMF-019, -induced relaxation in hypertensive coronary
arteries and showed no effects on vasodilatory response to acetylcholine. My results also suggest
the possible impairment of PI3K/AKT/eNOS pathway mediated by GRK2 activation in
hypertensive coronary arteries.
My final aim was to check whether apelin signaling is impaired in coronary arteries only
under hypertensive conditions or if it occurs in other disease conditions. My data suggests that
apelin signaling is impaired in coronary arteries exposed to cigarette smoke extract (CSE), a model
for secondhand smoke exposure. Interestingly, similar to hypertensive coronary arteries, apelin lost its beneficial vasodilatory effects possibly through the GRK2 activation in CSE treated
coronary arteries.
Overall, this research provides evidence that apelin behaves differently under physiological
and pathological conditions. As a point of fact, apelin not only lost its beneficial effects but also
might have negative effects under pathological conditions such as hypertension and secondhand
smoke exposure. I anticipate that the results from this approach will be useful in improving the
therapeutic strategies with apelin and other APJ receptor agonists that are aimed to alleviate
different cardiovascular disorders
Sustainable Thermosetting Polymers: Biobased Epoxy Resin Systems and Aqueous Non-Isocyanate Polyurethanes
Get PDFIn recent years, there has been a desire to seek alternatives to petrochemically derived materials. These alternatives can be derived from renewable sources such as vegetable oils. However, methods for achieving sustainability are not limited to only resourcing materials from bio-based sources but can also be achieved by utilizing safer synthesis techniques, reducing cure times, and eliminating volatile organic content in thermoset coating formulations. This dissertation sets out to achieve a goal the sustainability across different fields. Epoxidized sucrose soyate is a versatile bio-based materials that is typically synthesized utilizing hydrogen peroxide and acetic acid. A proposed safer alternative utilizes Oxone to generate dimethyldioxirane intermediates at room temperature to achieve the epoxidation of unsaturated sites in sucrose soyate and other vegetable oils such as soybean oil and hempseed oil. Thermosets made from epoxidized bio-based sources synthesized from dimethyldioxirane intermediates or in-situ generated peracids showed little to no difference in thermal and coatings properties. The use of epoxidized sucrose soyate with reactive diluents in cationic photopolymerization was also explored. The thermal characterizations of the thermoset coatings created utilizing this method indicate that crosslinking had not occurred to completion. In an effort to reduce the use of volatile organic content the feasibility of utilizing cyclic carbonates and primary carbamates in water borne polyurethane systems was explored. It was found that utilizing cyclic carbonates with higher ring strain, such as 6-membered cyclic carbonates, provides a potential way for creating non-isocyanate crosslinking thermoset coatings from waterborne polyurethane dispersions
Molecular Mapping of QTL for Genetic Transformation-Related Trait and CRISPR/Cas9-Mediated Gene Editing in Wheat
Get PDFPlant transformation is a valuable tool for gene characterization and crop improvement. However, wheat transformation is greatly impacted by genotype dependency for successful regeneration of the transgenic plants. For improving disease resistance in wheat, targeting host genes for disease susceptibility has become one of the most attractive strategies. This study aimed to 1) identify the QTL associated with a genetic transformation-related trait (plant regeneration capability from calli derived from immature embryos); 2) targeting the wheat Tsn1 gene for susceptibility to tan spot disease, using CRISPR/Cas9 vector cassette delivered by Agrobacterium and particle bombardment mediated transformation; 3) targeting wheat TaHRC gene (encoding for reticulum histidine-rich calcium binding protein) at the Fhb1 locus involved in the resistance/susceptibility to Fusarium head blight (FHB) resistance, using haploid induction coupled with the CRISPR/Cas9 genome editing technology. Using phenotypic and genotypic data from a mapping population of 186 recombinant inbred lines derived from the cross between wheat cultivar Bobwhite and wheat line PI 277012, two QTL controlling plant regeneration capability in Bobwhite were detected on chromosome 1A and 6D. To target the Tsn1 gene in wheat, two and 30 T0 transgenic plants were generated from Fielder through the Agrobacterium-mediated transformation and Bobwhite by the biolistic transformation, respectively. However, no Tsn1 mutant was identified by ToxA infiltration on 1176 T1 transgenic plants. Previous studies revealed two allelic forms of the TaHRC gene with TaHRC-S controlling susceptibility and TaHRC-R resistance to FHB, and deletion of TaHRC-S renders wheat FHB resistance. To target TaHRC, pollens of the transgenic hybrid corn variety Hi-II with high expression of Cas9 and gRNA were used to pollinate emasculated spikes of wheat variety Dayn with TaHRC-S and TaHRC-R. After embryo rescue, of the 82 haploid plants screened, 12 plants were identified having mutations at the target sites of TaHRC-S allele and 2 plants at the target site of TaHRC-R allele. Doubled haploid plants are being generated from these gene-edited haploid plants and will be evaluated for FHB resistance. This study may facilitate our understanding of genetics of transformation-related traits and provide a novel approach for improving disease resistance in wheat
A Path Analysis Model Examining Parent Perception, Dieting, and Food Behaviors on BMI Among Predominately Hispanic Families with Preschool Children
Get PDFChildren and adults continue to suffer from obesity, which poses a great public health threat. This research focused on protective factors for its prevention. Parent?s perception of a healthy child?s body size, parent dieting, child dieting, and food behaviors influence on Hispanic preschool children?s weight (assessed by BMI z-scores and raw BMI) was examined in 534 mother-child dyads. A hypothesized model was constructed and tested through a secondary analysis of baseline data collected in fall 2018 from the South Texas Early Prevention Study Project. All data except BMI, were collected via self-administered questionnaires completed by the parents (or guardians). Path analysis was conducted to identify relationships. The conceptual model consisted of various simple and mediated models (i.e., the age model, the perception model, the parent model, and the child model). Inside each of these models, several paths were found to be statistically significant. Within the parent-mediated model, perception of a healthy child?s body size and parent?s dieting had a statistically significant effect on raw BMI. Within the full model, age, parent?s dieting, and child?s dieting had the greatest effects on child?s BMI z-score. As a result, children whose mothers were currently dieting are significantly more likely to diet and gain weight. This effect increased with age. Mothers are crucial to the development of children, and a great deal of research has confirmed this. Perceptions of weight, shape, and appearance are sociocultural values passed on by mothers. Therefore, it is critical to ensure that parents have healthy behaviors not only for themselves but for the sake of their children. As the population of Hispanics increases in the United States, it is important to continue to examine this area in this population
Exploratory Analysis of Mass Shooting Offenders in U.S. Journalism
Get PDFMass shootings are commonplace in media. The media reports as to why the events happened, often within days or hours. These reasons attributed often lead to political debates on how to deter future mass casualty events. The portrayal by the media is important because their perceptions influence the perceptions of their audience. As of beginning this thesis, there is a lack of research utilizing qualitative analysis to analyze the offender reports using large datasets from the media. This thesis is an exploratory analysis and examines the number of times the offender's name is mentioned to determine whether there are sufficient conditions for the copycat effect. This thesis also explores the attributed wording used in the media articles of mass shooting offenders within the initial 30 days of the shooting. Finally, coverage between the newspapers and events is discussed as well to explore whether certain shootings were provided significantly more coverage.
Identification of Stem Rust Resistance Quantitative Trait Loci in Durum Wheat Populations
Get PDFStem rust (Puccinia graminis f. sp. tritici) negatively impacts durum wheat production worldwide. Resistance loci from four resistant landrace durum wheat lines were identified in biparental F?5? recombinant inbred line (RIL) populations after crossing with the susceptible line ?Rusty?. The populations were tested with foreign race of stem rust from Eastern Africa and Europe (JRCQC, TRTTF, TTRTF, and TTKSK) and local races from United States Upper Midwest (MCCF and RKQQ), followed by genotyping and linkage map construction to identify stem rust resistant quantitative trait loci (QTLs). At least one stem rust resistance QTL was identified in each population with a total of twelve QTLs identified overall. Seven of the identified QTL regions validated previously published stem rust resistance genes and the other five identified potentially novel stem rust resistance genes. Various resistance mechanisms were determined from QTL regions that provide stem rust resistance to the four durum wheat RIL populations