University Distinguished Professors

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Becoming a University Distinguished Professor (UDP) is the highest honor that can be awarded to a faculty member at North Dakota State University. Research from these individuals can be found here. More information about University Distinguished Professors can be found at https://www.ndsu.edu/president/honors/distinguished_professors/

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2007-2008 NDSU Information Technology Division Annual Report
(North Dakota State University, 2008)
2008-2009 NDSU Information Technology Division Annual Report
(North Dakota State University, 2009)
4-Dimethylamino Pyridine (DMAP) Catalyst with Fluxional Chirality: Synthesis and Applications
(North Dakota State University, 2016) Ma, Gaoyuan
Organocatalysis using small organic molecules to catalyze organic transformations, has emerged as a powerful synthetic tool that is complementary to metal-catalyzed transformations and remarkably promote stereoselective synthesis. Our group has designed useful templates, ligands, and additives that use fluxional groups to control and/or enhance stereoselectivity in a variety of asymmetric transformations. A key feature of this strategy is that the size of the fluxional substituent can be varied readily. As an extension of this strategy we became interested in developing efficient and broadly applicable and adjustable 4-dimethylaminopyridine (DMAP) organocatalysts. In our design, we surmised that a fluxional group would be effective in relaying stereochemical information from the fixed chiral center to the catalytic center of DMAP. Presented herein the synthesis of novel fluxionally chiral DMAP catalysts and their application in the acylative kinetic resolution of secondary alcohols and axially chiral biaryls, dynamic kinetic resolution of chiral biaryls with low rotation barriers and allylic substitution reactions. In the beginning, a comprehensive study of the chiral relay concept in enantioselective transformations was reviewed and the historic and current story of the chiral relay concept is covered. The design and synthesis of fluxionally chiral 4-dimethylaminopyridine catalysts was introduced. The key issues addressed in this chapter include the design concept regarding a stereoselective fluxionally 4-dimethylaminopyridine catalyst and muti-step synthesis strategies developed for catalyst synthesis. The development of fluxionally chiral 4-dimethylaminopyridine catalysts in the acylative kinetic resolution studies of secondary alcohols as well as axially chiral biaryls is investigated. Six different secondary alcohols are resolved with good selectivity factors (6-37) and ten biaryl substrates are resolved with moderate to high selectivity factors (10-51). Dynamic kinetic resolution has more practical applications to organic synthesis than simple kinetic resolution. The dynamic kinetic resolution of atropisomeric biaryls using the novel fluxionally chiral 4-dimethylaminopyridine catalysts was explored and the corresponding acylated products were obtained with 11-80 %ee. The newly designed DMAP catalysts containing fluxional groups as a stereocontrol unit could also be effectively applied as a nucleophilic catalyst in asymmetric allylic aminations. A range of α-methylene-β-amino esters were obtained with good yields and selectivities (up to 72 %ee).
Achiral Templates in Asymmetric Catalysis: Applications in Construction of All Carbon Quaternary Centers
(North Dakota State University, 2018) Subramanian, Hariharaputhiran
Conjugated olefins are readily available and inexpensive starting materials and their functionalization offers a rapid access to many important building blocks for organic synthesis. The functionalization of these olefins by asymmetric catalytic methods for the formation of C-C and C-X bonds is an active area of research. Major advances in this field are not only triggered by the development of new catalysts but also by engineering of new acceptor olefins. In our lab we have successfully developed acceptor olefins appended to alkoxyimidazoles as a novel template. Using these templated acceptors, we demonstrated methodologies to construct all carbon-quaternary centers, one of the demanding tasks in synthetic methodology development. We have also made significant efforts towards understanding the solution structures of the intermediates involved in the catalytic asymmetric reactions developed in our lab. In chapter 1, the importance of templated acceptors in the field of chemical synthesis with special emphasis on acylimidazoles is reviewed. The versatility of the N-alkylimidazole templates is showcased by their utility in several organic transformations. In chapter 2, modes of activation of acceptor olefins by catalysts, need for templated acceptors and challenges associated with designing an asymmetric catalytic process is described. Our approach in designing novel acceptors based on imidazoles is also described. In chapter 3 the synthetic utility of these novel N-alkoxyimidazole based acceptors is shown by enantioselective construction all carbon quaternary centers by Lewis-acid catalysis. We also compare the effectiveness of other templates such as oxazolidinone and N-methylimidazoles in the Lewis-acidic catalyzed Friedel-Crafts alkylation reaction. The effect of various parameters such as Lewis acid, chiral ligands, temperature, additives and solvents on the conjugate addition of Friedel-Crafts nucleophiles are presented in this chapter. In chapter 4, our research efforts toward understanding solution structures of intermediates involved in catalytic asymmetric reactions are presented. A combination of Diffusion Ordered Spectroscopy (DOSY), heteronuclear NMR spectroscopy, mass spectrometry and X-ray crystallography has been used to study the solution structure of intermediates involved in asymmetric catalytic reactions. In chapter 5, a future outlook on templated chemistry developed in our laboratory is presented. Some preliminary results pertinent to future projects are presented.
Agricultural Processing - A Major Contribution to the North Dakota Economy
(1989) Helgeson, Del L.; D'Appolonia, Bert
Agronomic Practices that Impact Grain Quality Factors of Durum Wheat (Triticum Turgidum L. Var. Durum Desf.)
(North Dakota State University, 2016) Forster, Shana M.
Durum wheat is a type of wheat primarily used for pasta production. North Dakota is the leading producer of durum wheat in the US with average yields of 2700 kg ha-1. Durum wheat price discounts are common and occur due to disease, heavy metal contamination, and environmental issues that impact grain quality. Studies were conducted in order to determine how agronomic approaches might impact durum quality. Experiments were conducted in order to determine what impact planting date, cultivar, and seeding rate had on the agronomic performance and quality of end-use traits. In general, a delay in planting date resulted in a significant decrease in yield and test weight for all cultivars. Cultivars differed for many of the end-use traits evaluated such as protein content, falling number, and vitreous kernel. Seeding rate had little impact on the traits evaluated. No combination of planting date and cultivar was identified that consistently resulted in grain marketed as US Grade 1 hard amber durum (HAD), or ‘choice durum’. Cultivar selection remains the best option for maintaining end-use traits. The effect of Zn fertilizer source and placement on grain Cd were evaluated. Treatments evaluated had no negative impact on grain yield or test weight. The foliar application of 1.1 kg Zn ha-1 Zn-EDTA in combination with 33 kg N ha-1 in the form of UAN applied at Feekes 10 growth stage (boot stage) resulted in the lowest grain Cd, and highest grain Zn, Fe and protein and represents an approach of biofortification for durum wheat.
Analysis and Identification of QTL for Resistance to Sclerotinia Sclerotiorum in Pea (Pisum sativum L.)
(North Dakota State University, 2018) Ashtari Mahini, Rahil
White mold caused by Sclerotinia sclerotiorumi s one of the most devastating diseases infecting field pea (Pisum sativum L.) which causes severe yield loss worldwide. Population 17 (Lifter/ PI240515), and Population 19 (PI169603/ Medora) were developed by single seed descent and screened by greenhouse evaluation and detached stem assay to identify potential sources of white mold resistance. Twenty-two partial resistant inbred lines were identified with short internode which met at least two resistance criteria based on lesion expansion inhibition (LEI) and nodal transmission inhibition (NTI). To find SNPs (single nucleotide polymorphism) responsible for white mold resistance, Populations 17 and 19 were genotyped using GBS (genotyping by sequencing) methodology and analyzed with the GBS-SNP-CROP pipeline. Linkage maps were constructed for each population and a composite map based on shared SNPs between the two populations was also generated. Nineteen QTL were identified as contributing to resistance to white mold. Seventeen were associated with LEI and two were associated with NTI. The QTL responsible for lesion expansion on LG VII were duplicated in the short internode subset of both populations. Partially resistant inbred lines and QTL responsible for white mold resistance identified in this study can be useful as resources for resistance to S. sclerotiorum in further experiments aimed at developing resistant cultivars.
Animal Biotechnology
(North Dakota State University, 1990) Redmer, D.A.; Reynolds, L.P.
Annual Report of the North Dakota Agricultural Experiment Station
(1982)
An Application of Association Rule Mining to Unit Test Selection
(North Dakota State University, 2013) Gunderson, Karl Nils
Appropriate selection of unit tests during the software development process is vital when many unit tests exist. The developer may be unfamiliar with some tests and non-obvious relationships between application code and test code may exist. Poor test selection may lead to defects. This is especially true when the application is large and many developers are involved. By the application of association rule mining to the unit test selection process and by comparison with extant selection techniques, we will provide a quantitative analysis of the benefits of heuristic and its limit to development where process patterns are stable.
Arginine Supplementation Strategies during Gestation: Impacts on Dams and Offspring
(North Dakota State University, 2015) Bjertness, Jena Lee
We hypothesize rumen-protected arginine supplementation during gestation will mitigate deleterious offspring effects caused by undernutrition. Experiment 1: non-pregnant ewes were supplemented with rumen-protected arginine at varying doses to assess effects on circulating amino acids and carotid hemodynamics. Arginine concentrations post-supplementation were greater in ewes supplemented with 180 vs. 90 mg/kg BW, and vascular resistance indices were lesser with 180 mg/kg BW; therefore, 180 mg/kg BW was used in experiment 2. Experiment 2: nutrient-restricted pregnant ewes were supplemented with rumen-protected arginine and maternal and offspring growth and physiological responses were measured. Arginine supplementation to nutrient restricted ewes improved offspring development compared to restricted ewes without supplementation. Circulating amino acids in offspring were efficiently metabolized, which may contribute to improved growth and development. There was no change in carotid hemodynamics in supplemented pregnant ewes. Further research should determine how arginine improves development, as this dietary supplement could rescue at-risk pregnancies.
Ascochyta Blight of Chickpea
(North Dakota State University, 2008) Markell, Samuel G.
Association Mapping and Genetic Diversity Studies of Agronomic and Quality Traits in Durum Wheat [Triticum turgidum L. var. durum (Desf.)]
(North Dakota State University, 2017) Johnson, Marina
Genetic diversity studies in breeding programs are important to identify parental lines for hybridization and introgression of desirable alleles into elite germplasm. The genetic diversity analysis of 283 North Dakota State University (NDSU) advanced durum wheat breeding lines developed during the last 20 years indicated that the population was structured according to its breeding history. Total genetic diversity analysis (HT = 0.334) showed adequate level of genetic variation. The results will help in breeding efforts to broaden the genetic base and select lines for crossing as well as for genetic and genomic studies to facilitate the combination of desirable alleles. The quantitative nature of important target traits, combined with environmental effects, makes it difficult to bring the desirable improvement in durum wheat to meet the expectations of all the stakeholders involved in the durum wheat industry. With an objective to identify molecular markers for marker-assisted breeding (MAB), the present study attempted to identify marker-trait associations for six agronomic and 29 quality traits using a genome-wide association study (GWAS) mapping approach. The study used two types of phenotypic datasets, a historic unbalanced dataset belonging to a total of 80 environments collected over a period of 16 years and a balanced dataset collected from two environments, to identify the applicability of historic unbalanced phenotypic data for GWAS analysis. A total of 292 QTL were identified for agronomic and quality traits, with 10 QTL showing major effects (R2 >15%). Over 45% of QTL for agronomic and quality traits were present in both the unbalanced and balanced datasets, with about 50% of those present in both environments in the balanced dataset. Genome-wide association mapping studies identified several candidate markers for use in marker-assisted selection (MAS) for height, gluten strength, distribution of small kernels, polyphenol oxidase (PPO) activity, and yield.
Association Studies on Pre-Germination Flooding Tolerance and Cell Wall Components Related to Plant Architecture in Dry Bean
(North Dakota State University, 2018) Walter, Katelynn
Dry bean breeding programs have made significant advances in combating both abiotic and biotic stresses as well as improving plant architectural traits via selective breeding. Flooding can cause complete crop loss in dry bean. On the other hand, breeding for an upright architecture in dry bean has been a breeding target in several programs. However, the stem cell wall components underlying this change have yet to be studied. This research focused on analyzing the cell wall components that might be involved in dry bean architecture as well as pre-germination flooding tolerance in dry bean. For the plant architecture study, two significant genomic regions were identified on Pv07 and Pv08 associated with lignin accumulation in dry bean. For the pre-germination flooding study, one unpigmented seed coat genotype (Verano) and three pigmented seed coat genotypes (Indeterminate Jamaica Red, Durango, and Midnight) had germination rates similar to that of the tolerant check.
Atropisomeric Chromophores as Catalysts and Substrates for Asymmetric Light Induced Transformations
(North Dakota State University, 2016) Vallavoju, Nandini
Photochemical transformations hold a unique place as they can provide access to molecules with unique stereochemical and structurally complex scaffolds, thus serving as a complementary approach to thermal transformations. However, asymmetric photoreactions have been under-explored due to the challenges in controlling the nature of the excited state(s). Various elegant strategies have been developed by chemists to address this bottleneck and achieved varying degrees of success. This dissertation describes a novel and unique strategy that employs atropisomeric thioureas as organo-photocatalysts to perform desired chemical transformations. The motivation of the thesis is to develop an alternative strategy that does not depend on energy/electron transfer processes to initiate the photoreactions. This dissertation describes another unique strategy that employs atropisomeric chromophores where axial chirality in the reactant is transferred to point chirality in the photoproduct(s). This research explains about rotamers control in the ground state that allows stereospecific phototransformations in the excited state(s) thus leading to enantioenriched product(s). The chapter 1 introduces the fundamental differences between asymmetric photochemical reactions and conventional thermal method. Further, an overview of various methodologies developed towards asymmetric photochemical transformations are detailed. In chapter 2 and chapter 3, various thiourea-based organo-photocatalysts were developed for enantioselective intramolecular [2+2] photocycloaddition of coumarin derivatives. The atropisomeric thioureas were found to be efficient in promoting the photocycloaddition leading to the corresponding products with high enantioselectivity (77-96% ee) at low catalyst loading (1-10 mol%). The photocatalytic cycle is proposed to proceed by the mechanism of ‘energy sharing’ via the formation of both static and dynamic complexes (exciplex formation), which is promoted by hydrogen bonding. Chapter 4 describes the intermolecular [2+2]-photocycloaddition of coumarin with tetramethylethylene promoted by thiourea catalysts. The photocatalytic cycle of coumarin mediated by thioureas is proposed to proceed via a combination of minimized aggregation, enhanced intersystem crossing and altered excited state lifetime(s), which is promoted by hydrogen bonding. 5 describes the enantiospecific hydrogen abstraction of atropisomeric enone carboxamides leading to spiro-β-lactam photoproduct(s). Divergent photoreactivity was observed based on restricted bond rotation(s) in atropisomeric substrates, when compared to their achiral analogue. The hydrogen abstraction also proceeded efficiently under visible light sensitized irradiation.
Attempted Total Syntheses of a Novel Lycopodine-Class Alkaloid and (R)-Myricanol, Compounds for the Treatment of Alzheimer's Disease
(North Dakota State University, 2013) Ostlund, Anthony John
Alzheimer's Disease (AD) is a significant challenge to both the pharmaceutical world as well as the synthetic organic chemistry world. One of the most important problems in this field is the lack of a unified approach to the most biologically active class of natural products for the treatment of AD, the lycopodine alkaloids. Presented herein is an attempt at the total synthesis of a novel member of this family. The synthesis spans three complete generations of retrosynthesis and forward progress. In the ultimate effort, the carbon backbone of the entire lycopodine class was successfully synthesized using a 6 step process in 44% overall yield. Features of this synthesis are the formation of an intermediate aldehyde by tandem Horner-Wadsworth-Emmons olefination/Baylis-Hillman reaction, quantitative reduction resulting in a monoprotected diol, cationic Au(I) O-vinylation, and microwave assisted Claisen rearrangement. The final step towards the backbone was realized using a hydrozirconation/transmetalation sequence with addition to the aldehyde to make the penultimate allylic alcohol in 54% yield. Final studies on the elimation of the allylic alcohol to create the desired 1,3-diene functionality show limited access to this important precursor. Simultaneous model system studies have shown that an intramolecular, cationic Rh(I)-catalyzed ynamide Diels-Alder reaction is feasible to set the B and D rings of the final lycopodine core, although the reaction requires optimization. Model systems for the unique intramolecular allylation proposed in the retrosynthesis also show feasibility, however the intramolecular variant has not been fully explored. Additional studies towards the total synthesis (R)-myricanol are also presented as a continuance of efforts towards general approaches to AD combative compounds. Featured are straightforward methods to the two main segments of the natural product, including a three-step process to synthesize the southern half. Finally, a successful 2-step synthesis of (R)-convolutamydine E is used to showcase an In(0)-mediated allylation methodology.
Augmented Expression of Apelin/APJ in the Paraventricular Nuclei of Rats after Myocardial Infarction
(North Dakota State University, 2012) Pingili, Ajeeth Kumar
Heart failure (HF) is a disease condition in which insufficient blood is pumped through the body. The pathophysiology of HF is multisystematic and includes a collection of different responses to compensate for the inability of the heart to pump the blood with the most important outcome being increased sympathetic nervous system (SNS) activity. Increased SNS activity leads to reclaim the reserved cardiac function. However, this adaptive response is short term and deleterious. The central mechanisms that lead to increased SNS activity during conditions of HF remain enigmatic. APJ, a G-protein-coupled receptor and its endogenous ligand, is a novel neuroendocrine system. Previous studies from us and others indicated that central administration or over expression of apelin in brain cardiovascular regulatory areas resulted in an increase in blood pressure, sympathetic nerve activity and cardiac hypertrophy. The main objective of this study is to determine whether the Apelin/APJ system is involved in increased SNS activation during HF. We created HF rat models by left coronary artery ligation. Apelin and APJ receptor mRNA levels were measured in cardiovascular regions of the brain of sham and myocardial infarction (MI) rats. Results showed a significant increase in the levels of Apelin/APJ mRNA levels in paraventricular nuclei (PVN) and rostral ventrolateral medulla (RVLM) in MI rats as compared to sham rats. To determine the functional role of elevated APJ receptor in these cardiovascular regulatory regions of the brain during HF, we constructed a lentiviral vector carrying an APJ shRNA (Lenti-APJ-shRNA) to knockdown the APJ receptor. Efficiency of the lentiviral vector to knockdown the APJ receptor was confirmed in vitro by transducing a Cath.a cell line and a primary neuronal cell culture with Lenti-APJ-shRNA. In order to determine the effect of silencing of the APJ receptor in vivo, Lenti-APJ-shRNA virus was injected into the PVN of the MI and sham rats. Results showed knockdown of APJ receptor improved left ventricular function and decreased myocardial fibrosis and hypertrophy in MI rats. Thus, this study shows that PVN plays an important role in sympatho excitation and pathophysiology of HF and these findings may help in developing effective therapies for HF.
Augmenting Fungicidal Activity of Tetraconazole with Chemosensitization Agents for Cercospora Leaf Spot Management
(North Dakota State University, 2017) Metz, Nicholas James
Cercospora beticola (Sacc.) is the causal agent of Cercospora leaf spot (CLS). CLS is considered to be one of the most destructive foliar diseases of sugar beet in the world. CLS is managed in part through resistant cultivars, crop rotation, and cultural practices, but timely fungicide applications are necessary to manage disease effectively. Heavy reliance on fungicides to manage CLS has led to the development of resistance to multiple classes of fungicides. The most widely used class of fungicides is the demethylation inhibitors (DMIs). DMI-resistant C. beticola isolates have been increasing in incidence over the past decade. Chemosensitization agents (CAs) are compounds that have little to no antifungal activity, but may increase efficacy of commercial fungicides when co-applied. CAs could lead to better management of CLS and reduced production costs.
An Automatic Weather Station Network For North Dakota
(North Dakota State University, 1990) Enz, John W.
Basis for Selected North Dakota Crops
(North Dakota State University, 2003) Flaskerud, George

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