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Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry: A High-Throughput Platform In Metabolomics For Assessment Of Lifestyle Interventions In Human Health, Naomi L. Kuehnbaum 2014 McMaster University

Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry: A High-Throughput Platform In Metabolomics For Assessment Of Lifestyle Interventions In Human Health, Naomi L. Kuehnbaum

Open Access Dissertations and Theses

Research in this thesis has focused on development and application of novel methodologies that enhance sample throughput and data fidelity when performing untargeted metabolome profiling by multisegment injection-capillary electrophoresis-mass spectrometry (MSI-CE-MS). Metabolomics is a valuable tool in functional genomics research to investigate underlying molecular mechanisms associated with human health since metabolites are “real-world” end-products of gene expression. CE-MS is well-suited for metabolomics because it is a high efficiency microseparation technique that can be used to resolve complex mixtures of polar metabolites in human biofluids without complicated sample workup. In this thesis, a novel CE-MS assay for estrogens and their intact ...


2014 Scas Annual Meeting Program, 2014 University of South Carolina

2014 Scas Annual Meeting Program

Journal of the South Carolina Academy of Science

No abstract provided.


Genotypic And Phenotypic Characterization Of Aerosolized Bacteria Collected From African Dust Events, Christina A. Wilson, Robin L. Brigmon, Chris Yeager, Garriet W. Smith, Shawn W. Polson 2014 University of South Carolina

Genotypic And Phenotypic Characterization Of Aerosolized Bacteria Collected From African Dust Events, Christina A. Wilson, Robin L. Brigmon, Chris Yeager, Garriet W. Smith, Shawn W. Polson

Journal of the South Carolina Academy of Science

Twenty-one bacteria were isolated and characterized from air samples collected in Africa and the Caribbean by the United States Geological Survey (USGS). Isolates were selected based on preliminary characterization as possible pathogens. Identification of the bacterial isolates was achieved using 16S rRNA gene sequence analysis, fatty acid methyl esters (FAMEs) profiling, the BIOLOG Microlog® System (carbon substrate assay), and repetitive extragenic palindromic (REP)-PCR analysis. The majority of isolates (18/21) were identified as species of the genus Bacillus. Three isolates were classified within the Bacillus cereus senso lato group, which includes Bacillus anthracis, Bacillus thuringiensis, and Bacillus cereus strains ...


Scas Officers And Council Members 2014-2015, 2014 University of South Carolina

Scas Officers And Council Members 2014-2015

Journal of the South Carolina Academy of Science

No abstract provided.


Table Of Contents, 2014 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


The Development Of Metal-Organic Compounds For Use As Molecular Imaging Agents, Emily J. Simpson 2014 Western University

The Development Of Metal-Organic Compounds For Use As Molecular Imaging Agents, Emily J. Simpson

University of Western Ontario - Electronic Thesis and Dissertation Repository

Molecular imaging probes allow for the non-invasive diagnosis of many diseases through the use of a targeting entity for site specific delivery, as well as a signal for external visualization of probe accumulation in the body. This thesis will focus on the development of new approaches to synthesize targeting peptides and chelators for radionuclide incorporation towards the design of novel molecular imaging probes.

Histidine is a tridentate chelator that can be attached in a pendant fashion to a biomolecule in order to coordinate technetium-99m. Once coordinated, it forms a neutral complex that is capable of forming diastereomers with inverted stereochemistry ...


Gamma-Radiolysis Kinetics Of Liquid, Vapour And Supercritical Water, Nastaran Yousefi 2014 Western University

Gamma-Radiolysis Kinetics Of Liquid, Vapour And Supercritical Water, Nastaran Yousefi

University of Western Ontario - Electronic Thesis and Dissertation Repository

Inadequate understanding of radiation-induced water chemistry under supercritical conditions has been identified as one of the important obstacles in the development of a supercritical water-cooled reactor. Radiolysis of supercritical water generates a variety of redox reactive species, but their persistence in supercritical water is not well understood. This thesis describes the work performed towards addressing this deficiency: (1) the development of a reliable experimental method to determine the concentrations of water radiolysis products, primarily H2, O2 and H2O2, formed under g-irradiation of sub- and supercritical water (SCW), (2) the expansion of the application ranges of ...


Optimization Of P-Type Czts Nanocrystal Thin Film Layers For Applications In Low Cost Photovoltaic Devices, Kyle S.B. Jeffs 2014 Western University

Optimization Of P-Type Czts Nanocrystal Thin Film Layers For Applications In Low Cost Photovoltaic Devices, Kyle S.B. Jeffs

University of Western Ontario - Electronic Thesis and Dissertation Repository

In this thesis Cu2ZnSnS4 nanocrystal synthesis was optimized by way of photoelectrochemical measurements through tuning the stoichiometry. Formation of a Cu2ZnSnS4 light-absorbing layer was studied using multiple depositions methods. These included dropcasting, electrophoretic deposition, and use of 3-mercaptopropyl trimethoxysilane as a chemical linker. Dropcasting samples were compared according to the solvents used to suspend the nanocrystals. Photoelectrochemical measurements were used to compare dropcasting with electrophoretic deposition and use of 3-mercaptopropyl trimethoxysilane as a chemical linker. Dropcasting was shown to be the least effective method of depositing the light-absorbing layer. Samples prepared by electrophoretic deposition were optimized according to a number ...


Synthesis Of Carbohydrate Functionalized Dendrons For Use As Multivalent Scaffold And In Self-Assembled Structures, Namrata Jain 2014 Western University

Synthesis Of Carbohydrate Functionalized Dendrons For Use As Multivalent Scaffold And In Self-Assembled Structures, Namrata Jain

University of Western Ontario - Electronic Thesis and Dissertation Repository

Carbohydrates are implicated in a large number of biological processes ranging from cell-cell interactions to bacterial and viral infection. Lectins are carbohydrate-binding proteins that are generally specific for certain sugars. However, typical carbohydrate–lectin interactions tend to have very low monomeric binding affinities. In many cases, the binding of saccharide ligands by protein receptors can be improved significantly through the attachment of multiple saccharide residues to a common support. Dendronized polymers constitute a class of macromolecules whose nanoscale size, rigidity, and functionality can be controlled with precision by tuning their molecular architecture. It is hypothesized that due to their large ...


Technology-Assisted Methodology In The Synthesis Of Medicinally Relevant N-Heterocycles, Nadeesha Ranasinghe 2014 Northeastern University

Technology-Assisted Methodology In The Synthesis Of Medicinally Relevant N-Heterocycles, Nadeesha Ranasinghe

Chemistry Dissertations

In recent years, modern technology such as microwave irradiation and continuous flow processes have emerged as valuable tools in chemical and pharmaceutical industry, facilitating the ever increasing demand for faster, greener and reproducible chemistry. This dissertation will discuss three projects that used technology platforms to synthesize medicinally relevant heterocycles. The first is the microwave and flow assisted synthesis of substituted indoles, aza-indoles and indole-2-carboxamides using the Hemetsberger-Knittel (HK) reaction. The indole ring is one of the most abundant heterocyclic scaffolds found in nature and forms an essential component of the framework of higher order protein structures. The HK indole synthesis ...


The Application Of Novel Donor Acceptor Cyclopropanes In The Synthesis Of Linearly Fused Tricyclic Triazoles, Michelle E. Flisar 2014 Western University

The Application Of Novel Donor Acceptor Cyclopropanes In The Synthesis Of Linearly Fused Tricyclic Triazoles, Michelle E. Flisar

University of Western Ontario - Electronic Thesis and Dissertation Repository

Previous work in the Kerr group has shown the success of donor-acceptor cyclopropanes as substrates in a variety of synthetic reactions; this document will apply the use of donor acceptor cyclopropanes in various synthetic reactions. This was done using a 2-substituted 1,1-cyclopropanediester, in the Overman Rearrangement, which has yet to be explored using DA cyclopropanes. Another useful DA cyclopropane is the novel acetylene-bearing donor acceptor diester cyclopropanes which would be synthetically useful in a wide variety of reactions. In particular, the Conia-ene cyclization occurred intramolecularly with this alkyne DA cyclopropane with a large library of nucleophiles. Finally, taking this ...


The Synthesis And Reactivity Of Novel Donor-Acceptor Cyclopropanes And Progress Towards Pyrrolidine Alkaloids, Michael R. Emmett 2014 Western University

The Synthesis And Reactivity Of Novel Donor-Acceptor Cyclopropanes And Progress Towards Pyrrolidine Alkaloids, Michael R. Emmett

University of Western Ontario - Electronic Thesis and Dissertation Repository

The first chapter of this thesis focuses on the synthesis and reactivity of cyclopropane hemimalonates. The cyclopropane hemimalonates can easily be synthesized from 1,1-cyclopropanediesters. The reactivity of cyclopropane hemimalonates with indole under ultra-high pressure conditions leads to ring opened adducts that are complementary to previous research in the Kerr group. The tandem ring opening decarboxylation reaction of cyclopropane hemimalonates led to the synthesis of γ-aminobutyric acid analogues. When an external nucleophile was not present, the cyclopropane hemimalonates could rearrange to form butyrolactones in good to excellent yields. The stereochemical integrity of the cyclopropane hemimalonate is retained through this process ...


The Design And Synthesis Of Pyrazolopyridazine Replacements For The Investigation Of Novel Treatment Of Human African Trypanosomiasis, Elizabeth Jones 2014 Northeastern University

The Design And Synthesis Of Pyrazolopyridazine Replacements For The Investigation Of Novel Treatment Of Human African Trypanosomiasis, Elizabeth Jones

Chemistry Master's Theses

Human African trypanosomiasis (HAT) is one of 17 diseases deemed by the World Health Organization (WHO) to be "neglected". Affecting approximately one seventh of the global population, neglected tropical diseases (NTDs) are a healthcare predicament that needs increased multidisciplinary efforts. These diseases affect some of the poorest populations of the world, making financial investment from pharmaceutical companies unprofitable, leading to a severe lack of funding for, and scientific interest in NTDs. This places the burden of efforts primarily on not-for-profit or academic laboratories like the Pollastri laboratory at Northeastern University.

The Pollastri lab used a target-repurposing approach to begin research ...


Application Of Mn(Iii) Oxidative Cyclizations To Natural Product Synthesis, Bryan Landschoot 2014 Western University

Application Of Mn(Iii) Oxidative Cyclizations To Natural Product Synthesis, Bryan Landschoot

University of Western Ontario - Electronic Thesis and Dissertation Repository

This work begins with a brief review of manganese(III) acetate free radical oxidative cyclization chemistry and its application toward functionalizing nitrogen containing heterocycles. Exploration of a cyclopropane ring opening reaction using indoline, and subsequent manganese(III) cyclization chemistry will be presented as a possible route towards a family of natural products called the flinderoles. Work on the construction of the core of several indole alkaloids from the genus Tabernaemontana, including tronocarpine, chippiine, and dippinine B, will be explored with utilization of manganese(III) cyclizations. Hopes of accessing an advanced common intermediate for each of these natural products will be ...


Electrogenerated Chemiluminescence Of Gold Nanoclusters, Mahdi Hesari 2014 Western University

Electrogenerated Chemiluminescence Of Gold Nanoclusters, Mahdi Hesari

University of Western Ontario - Electronic Thesis and Dissertation Repository

A series of monodispersed AuNCs including Au144(SR)60, Au38(SR)24 and Au25(SR)18z (z =1-, 0 and 1+, SR=2-phenylethanethiol) were prepared. All these nanoclusters showed molecule-like optical and electrochemical properties. These two features are essential for an electrogenerated chemiluminescence or electrochemiluminescence (ECL) study. The Au144(SR)60 showed a small HOMO-LUMO gap determined by electrochemistry. No ECL light was seen in the annihilation process, while NIR ECL was observed with tri-n- propylamine (TPrA) (Chapter 2). ECL was highly efficient in the Au38(SR)24/TPrA co- reactant system. This nanocluster also showed ECL emission with benzoyl ...


Characterization Of Fall Leaves As A Source Of Cellulosic Ethanol, Justin Burum 2014 Minnesota State University, Mankato

Characterization Of Fall Leaves As A Source Of Cellulosic Ethanol, Justin Burum

Journal of Undergraduate Research at Minnesota State University, Mankato

Ethanol is becoming increasingly popular as a fossil fuel additive or substitute. However, current production of ethanol from corn impacts food prices and appears to have an overall low net yield. New sources need to be identified and new processes developed for ethanol production. Cellulosic ethanol is one such new source. Plant material contains a large amount of cellulose and other polysaccharides which are potential feed stocks for ethanol production. The purpose of this experiment was to characterize the polysaccharide, lignin, and ash content of fall leaves to estimate their potential for ethanol production. A slight modification of the NREL ...


New Ligands For Lanthanides And Transition Metals Toward Magnetic Resonance Imaging Contrast Agents, Melissa M. Lewis 2014 Western University

New Ligands For Lanthanides And Transition Metals Toward Magnetic Resonance Imaging Contrast Agents, Melissa M. Lewis

University of Western Ontario - Electronic Thesis and Dissertation Repository

MRI is a non-invasive technique used in medical imaging. Although contrast agents have been used to enhance the image generated by MRI, it still suffers the major shortcoming of low sensitivity. This has led to a thrust to develop contrast agents that improve sensitivity by relaxivity and CEST. This thesis describes attempts made to aid in the development of sensitive MRI contrast agents.

Chapter 2 investigated pH dependent reversible binding on CEST effect and relaxivity in DO3AM complexes possessing a lone p-nitrophenol arm. Unfortunately, only the Tb3+complex had a small CEST signal. T1 relaxivity of the ...


Effect Of Sweeteners On The Renin-Angiotensin System In Rats, Jacob Ball 2014 Minnesota State University, Mankato

Effect Of Sweeteners On The Renin-Angiotensin System In Rats, Jacob Ball

Journal of Undergraduate Research at Minnesota State University, Mankato

Normal abundant dietary sugars such as fructose and sucrose can contribute to hypertension and other health issues. To avoid these health complications, many individuals use artificial sweeteners. An equivalent intake of some artificial sweeteners also can lead to hypertension. However, Stevia, a sweetener that is isolated from a Paraguayan plant, was shown in relevant literature to decrease blood pressure in both rat specimens and humans. The general purpose of this research project was to study the effect of Stevia, saccharin, and sucrose on the expression of two key components of the renin-angiotensin- aldosterone system (RAAS): prorenin receptor (PRR) and angiotensin ...


Pressure-Induced Magnetic Crossover Driven By Hydrogen Bonding In Cuf2(H2o)2(3-Chloropyridine), Kenneth R. O'Neal, Tatiana V. Brinzari, Joshua B. Wright, Chunli Ma, Santanab Giri, John A. Schlueter, Qian Wang, Puru Jena, Zhenxian Liu, Janice L. Musfeldt 2014 University of Tennessee, Knoxville

Pressure-Induced Magnetic Crossover Driven By Hydrogen Bonding In Cuf2(H2o)2(3-Chloropyridine), Kenneth R. O'Neal, Tatiana V. Brinzari, Joshua B. Wright, Chunli Ma, Santanab Giri, John A. Schlueter, Qian Wang, Puru Jena, Zhenxian Liu, Janice L. Musfeldt

Chemistry Publications and Other Works

Hydrogen bonding plays a foundational role in the life, earth, and chemical sciences, with its richness and strength depending on the situation. In molecular materials, these interactions determine assembly mechanisms, control superconductivity, and even permit magnetic exchange. In spite of its long-standing importance, exquisite control of hydrogen bonding in molecule-based magnets has only been realized in limited form and remains as one of the major challenges. Here, we report the discovery that pressure can tune the dimensionality of hydrogen bonding networks in CuF2(H2O)2(3-chloropyridine) to induce magnetic switching. Specifically, we reveal how the development of exchange pathways under ...


Oxidative Cyclizations Of Tertiary Pentenols And The Synthesis Of Β-Carboline Alkaloids, Geoffrey A. Phillips 2014 Western University

Oxidative Cyclizations Of Tertiary Pentenols And The Synthesis Of Β-Carboline Alkaloids, Geoffrey A. Phillips

University of Western Ontario - Electronic Thesis and Dissertation Repository

This thesis describes the work carried out on two projects. The first chapter of the thesis discusses the application of the second generation Co(nmp)2 catalyst towards the oxidative cyclization of tertiary pentenols through a modified Mukaiyama aerobic oxidative cyclization procedure.

The second chapter describes the progress made towards the synthesis of β-carboline alkaloids. The total synthesis of the alkaloid natural product cyclocapitelline is detailed along with the formal synthesis of the natural product chrysotricine.


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