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2022

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Articles 31 - 60 of 1634

Full-Text Articles in Chemistry

The Facile Preparation Of Bis(Imino)Pyridine Complexes Via Mechanochemistry And Inorganic Synthons Via Benign Reductants, Thomas Shaw Dec 2022

The Facile Preparation Of Bis(Imino)Pyridine Complexes Via Mechanochemistry And Inorganic Synthons Via Benign Reductants, Thomas Shaw

Electronic Theses and Dissertations, 2020-2023

This thesis is comprised of two key themes: (i) leveraging mechanochemical synthetic methods for the green preparation of bis(imino)pyridine ligands and associated first row transition metal coordination complexes, and (ii) the preparation and characterization of both historic and novel mid-valent inorganic synthons via the use of dimethylphenylsilane as a stoichiometric reducing agent. The first portion of this thesis highlights the utilization of solvent-free vibratory ball-milling in lieu of traditional, solvent-based refluxes. A variety of both bis(imino)pyridine ligands and complexes were formed in drastically reduced timeframes with solvent-economical work-up procedures. This methodology was also leveraged for the isolation of acetyl(imino)pyridine ligands …

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Synthesis And Application Of Functional Unimolecular [N]Catenanes In Novel Polymeric Materials, Mark Andrew Nosiglia Dec 2022

Synthesis And Application Of Functional Unimolecular [N]Catenanes In Novel Polymeric Materials, Mark Andrew Nosiglia

Arts & Sciences Graduate Student Theses and Dissertations

Mechanically interlocked molecules (MIMs) possess unique architectures and non-traditional degrees of freedom that arise from well-defined topologies that are achieved through precise mechanical bonding. Incorporation of MIMs into materials can thus provide an avenue to discover new and emergent macroscale properties. Here, the synthesis of a phenanthroline-based [2]catenane crosslinker and its incorporation into polyacrylate organogels is described. Specifically, Cu(I) metalation and de-metalation was used as a post-gelation strategy to tune the mechanical properties of a gel by controlling the conformational motions of integrated MIMs. The organogels were prepared via thermally initiated free radical polymerization, and Cu(I) metal was added in …

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Functionalized Plasmonic Nanostructures For Ultrasensitive Single Cell Analysis, Priya Rathi Dec 2022

Functionalized Plasmonic Nanostructures For Ultrasensitive Single Cell Analysis, Priya Rathi

Arts & Sciences Graduate Student Theses and Dissertations

Ultrasensitive detection and quantification of soluble, secreted and cell surface-bound proteins is critical for advancing our understanding of cellular systems, enabling effective drug development, novel therapies, and bio-diagnostics. However, exiting technologies are largely limited by their sensitivity, making the detection and quantification of low-abundant proteins extremely challenging. This forms a major barrier in various fields of biology and biomedical sciences. In this work, we introduce novel cellular analysis methodologies based on plasmon-enhanced fluorescence for analyzing cell structure and probing surface and secreted proteins from cells. In the first part, we introduce plasmon-enhanced expansion microscopy and demonstrate the effectiveness of employing …

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Development Of Novel Nucleophile-Intercepted Beckmann Fragmentations And Progress Toward The Total Synthesis Of 2(S)-Cathafoline, Evan M. Dunkley Dec 2022

Development Of Novel Nucleophile-Intercepted Beckmann Fragmentations And Progress Toward The Total Synthesis Of 2(S)-Cathafoline, Evan M. Dunkley

Dartmouth College Master’s Theses

This thesis is comprised of two chapters, the first being the discovery of a novel nucleophile-intercepted Beckmann fragmentation of [2.2.1] indoline systems that resulted in highly stereo- and regioselective reactions. Chapter one details the exploration of this reaction as well as its relevant background information detailing its significance. Chapter two describes the application of the novel nucleophile-intercepted Beckmann fragmentation in the context of a total synthesis of akuammilline alkaloid 2(S)-cathafoline. While the target natural product was never synthesized, unpredicted reactivity resulted in interesting discoveries worthy of discussion.

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Toward Enhancing The Synthesis Of Renewable Polymers: Feedstock Conversions And Functionalizable Copolymers, Tedd Casey Wiessner Dec 2022

Toward Enhancing The Synthesis Of Renewable Polymers: Feedstock Conversions And Functionalizable Copolymers, Tedd Casey Wiessner

Arts & Sciences Graduate Student Theses and Dissertations

This thesis describes research under the rubric of the Center for Sustainable Polymers that is aimed at two separate goals. The goal of the first project (Chapters 1 and 2) was to develop a deeper mechanistic understanding of a method for the synthesis of linear α-olefins, while the second aimed at synthesizing statistical copolymers that incorporate olefin-containing monomers through ring-opening transesterification polymerization and showing that these copolymers could be functionalized. In Chapter 1, published methods for the conversion of fatty acids to linear α-olefins are reviewed to provide context for the mechanistic work we accomplished (Chapter 2). In Chapter 2 …

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The Effect Of Ionization Density In Applications Of Radiation Detection, Dosimetry, And Therapy, Daniel Mulrow Dec 2022

The Effect Of Ionization Density In Applications Of Radiation Detection, Dosimetry, And Therapy, Daniel Mulrow

Arts & Sciences Graduate Student Theses and Dissertations

This dissertation covers a wide range of topics but is linked by the common theme of radiation interacting with materials and studying the result of those interactions. The introduction describes the fundamentals of how radiation interacts with material and how we are able to detect that radiation and the application of how we use those interactions in radiation oncology. The thesis starts with a chapter detailing the temperature dependence of the photophysics in two organic scintillators. This chapter is the foundation for a future study that will look the degree to which these scintillators can distinguish between gammas and neutrons …

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Local Spectroscopy Data Infrastructure: Solid State Nmr Crystallography With Experiment, First-Principal Analysis And Machine Learning, He Sun Dec 2022

Local Spectroscopy Data Infrastructure: Solid State Nmr Crystallography With Experiment, First-Principal Analysis And Machine Learning, He Sun

Arts & Sciences Graduate Student Theses and Dissertations

Solid-state magnetic resonance (SSNMR) spectroscopy is a powerful tool for obtaining precise information about the local bonding and morphology of materials. The detailed local structure of crystalline materials cannot be easily solved by traditional experimental methods such as X-ray diffraction (XRD). SSNMR combined with first principal calculation methods such as density functional theory (DFT) can be of great use in this research area. The methodology that is called “NMR crystallography” today has been widely applied to the determination of a wide range of solid materials with an increasing amount of computationally simulated NMR spectra. The construction of a well-established computational …

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Development Of Redox-Responsive Phenazine-Based Foldamers. Acylative Kinetic Resolution Of Hydroxamic Acids, Jingwei Yin Dec 2022

Development Of Redox-Responsive Phenazine-Based Foldamers. Acylative Kinetic Resolution Of Hydroxamic Acids, Jingwei Yin

Arts & Sciences Graduate Student Theses and Dissertations

Two different research directions have been presented in this thesis. The first project is about phenazine-based foldamers as molecular actuators. Researchers have been interested in the design and synthesis of foldamers and molecular actuators for years. We began our exploration by demonstrating that phenazine-1,6-dicarboxamides can function as redox-responsive molecular switches. We then designed and synthesized two generations of phenazine-based interleafed foldamers and studied their stability and redox behaviors under chemical and electrochemical conditions. In the second project, we have developed the first acylative kinetic resolution on hydroxamic acids. Although chiral hydroxamic acids have extensive applications, synthetic methods towards them are …

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Tracking Reducing Equivalents Between Cellular Compartments To Understand The Metabolic Demands Of Proliferation, Yahui Wang Dec 2022

Tracking Reducing Equivalents Between Cellular Compartments To Understand The Metabolic Demands Of Proliferation, Yahui Wang

Arts & Sciences Graduate Student Theses and Dissertations

Proliferating cancer cells compartmentalize metabolic reactions, many of which require reducing equivalents. This compartmentalization is functionally important, but it is challenging to study with current technologies. As a consequence, our understanding of proliferating metabolism has been limited. Here, I developed an approach to track reducing equivalents between cellular compartments. By applying this method to a panel of different cell lines under various conditions, I investigated a dysregulated metabolic phenotype in proliferating cells known as “aerobic glycolysis”. Aerobic glycolysis is characterized by an elevated rate of glucose fermentation to lactate irrespective of oxygen availability. Using the NCI-60 cell lines, I first …

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Non-Canonical Beta-Lactam Antibiotics, Brett Wesley Virgin-Downey Dec 2022

Non-Canonical Beta-Lactam Antibiotics, Brett Wesley Virgin-Downey

Arts & Sciences Graduate Student Theses and Dissertations

In canonical β-Lactam antibiotics, such as penicillin, the strained nature of the β-Lactam ring leads to acylation of the catalytic serine in the active site of transpeptidases. In 2018, our lab reported a novel mechanism for monocyclic β-lactam antibiotics in the inhibition of glutamine synthetase (GS) by a natural product, tabtoxinine-β-lactam (TβL) using a 3-hydroxy-β-lactam pharmacophore. This work aims to generalize the β-lactam scaffold from TβL to act as a warhead against ATP-dependent carboxylate-amine ligase enzymes, with dihydrofolate synthetase (DHFS) as the test case. A pure 3-hydroxy-β-lactam warhead was synthesized and ligated both chemically and chemoenzymatically to different pteridine mimics. …

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Effects Of Surface Ligation On Charge Extraction From Wurtzite Cadmium Selenide Quantum Platelets And Quantum Belts, Hailey Meyer Dec 2022

Effects Of Surface Ligation On Charge Extraction From Wurtzite Cadmium Selenide Quantum Platelets And Quantum Belts, Hailey Meyer

Arts & Sciences Graduate Student Theses and Dissertations

This dissertation presents the synthesis of flat, colloidal wurtzite CdSe quantum platelets and quantum belts for ligand exchange to novel and existing organic and inorganic L-, X-, and Z- type ligands. Use of these ligands in conjunction with the semiconductor nanocrystals allows for examination of their ligand exchange abilities, photoluminescence quenching efficiencies, and charge transfer properties.First, zinc and cadmium dithiocarbamate compounds [M(S2CNR1R2)2] are used as ligands on wurtzite CdSe quantum belts. Complete ligand exchange is achieved when the belts are initially ligated with Cd(oleate)2, a Z-type ligand, prior to the exchange, as opposed to n-octylamine or ammonia, which are both …

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Utilizing An Α,Β-Unsaturated Dicarboxylic Acid For A Defect Initiated Residue Removal During Cu Post-Chemical Mechanical Planarization Cleaning, Abigail L. Dudek, Kiana A. Cahue, Adam T. Caridi, Tatiana R. Cahue, Jason J. Keleher Dec 2022

Utilizing An Α,Β-Unsaturated Dicarboxylic Acid For A Defect Initiated Residue Removal During Cu Post-Chemical Mechanical Planarization Cleaning, Abigail L. Dudek, Kiana A. Cahue, Adam T. Caridi, Tatiana R. Cahue, Jason J. Keleher

Chemistry Department Faculty Articles

The development of post-Chemical Mechanical Planarization (p-CMP) cleaning processes is critical for the continued miniaturization of Integrated Circuit (IC) and logic device architecture. In order for further extension of Moore’s Law the minimization of critical defects is essential. This work focuses on the development of surface-active cleaning chemistries via the implementation of an α, β-unsaturated dicarboxylic acid additive to create synergy at the liquid-brush-wafer interface. More specifically, the implementation of Itaconic Acid (ItA) will chemically activate an organic residue (i.e., Cu(I)-BTA film) resulting in effective removal at significantly reduced CoF. This work demonstrates that the conjugated structure present in ItA …

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Uv-Light-Tunable P-/N-Type Chemiresistive Gas Sensors Based On Quasi-1d Tis3 Nanoribbons: Detection Of Isopropanol At Ppm Concentrations, Victor V. Sysoev, Andrey V. Lashkov, Alexey Lipatov, Ilya A. Plugin, Michael Bruns, Dirk Fuchs, Alexey S. Varezhnikov, Mustahsin Adib, Martin Sommer, Alexander Sinitskii Dec 2022

Uv-Light-Tunable P-/N-Type Chemiresistive Gas Sensors Based On Quasi-1d Tis3 Nanoribbons: Detection Of Isopropanol At Ppm Concentrations, Victor V. Sysoev, Andrey V. Lashkov, Alexey Lipatov, Ilya A. Plugin, Michael Bruns, Dirk Fuchs, Alexey S. Varezhnikov, Mustahsin Adib, Martin Sommer, Alexander Sinitskii

Department of Chemistry: Faculty Publications

The growing demand of society for gas sensors for energy-efficient environmental sensing stimulates studies of new electronic materials. Here, we investigated quasi-one-dimensional titanium trisulfide (TiS3) crystals for possible applications in chemiresistors and on-chip multisensor arrays. TiS3 nanoribbons were placed as a mat over a multielectrode chip to form an array of chemiresistive gas sensors. These sensors were exposed to isopropanol as a model analyte, which was mixed with air at low concentrations of 1–100 ppm that are below the Occupational Safety and Health Administration (OSHA) permissible exposure limit. The tests were performed at room temperature (RT), as …

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Water Management And Corrosion Performance From Protective Polymer Coatings With Spatially Controlled Hydrophilic Domains, Jessica M. Davison Dec 2022

Water Management And Corrosion Performance From Protective Polymer Coatings With Spatially Controlled Hydrophilic Domains, Jessica M. Davison

Dissertations

Metallic corrosion has become an annual multibillion-dollar problem for the industrialized world and global contamination issue through the process of repair, removing, and reapplying protective coatings. Typical corrosion resistant coatings are comprised of polymeric coating layers with anti-corrosive pigments, plasticizers, sacrificial additives, and/or other formulation materials, which are formulated to prevent, detect, and manage corrosion. Our counterintuitive approach was to improve upon the understanding of how, when, where, and why environmental contaminants (reactants, mainly water and electrolytes) driving corrosion, propagate and accumulate as localized hydrophilicity shifts within a model polymer coated substrate. Herein, hydrogel particles (HGP) were synthesized of defines …

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Enhanced Structural Control Of Soft-Templated Mesoporous Inorganic Thin Films By Inert Processing Conditions, Maximilliano Jesus Jara Fornerod, Alberto Alvarez-Fernandez, Eric R. Williams, Miximillian W.A. Skoda, Beatriz Prieto-Simon, Nicolas H. Voelcker, Morgan Stefik, Marc-Oliver Coppens, Stefan Guldin Dec 2022

Enhanced Structural Control Of Soft-Templated Mesoporous Inorganic Thin Films By Inert Processing Conditions, Maximilliano Jesus Jara Fornerod, Alberto Alvarez-Fernandez, Eric R. Williams, Miximillian W.A. Skoda, Beatriz Prieto-Simon, Nicolas H. Voelcker, Morgan Stefik, Marc-Oliver Coppens, Stefan Guldin

Faculty Publications

Mesoporous thin films are widely used for applications in need of high surface area and efficient mass and charge transport properties. A well-established fabrication process involves the supramolecular assembly of organic molecules (e.g., block copolymers and surfactants) with inorganic materials obtained by sol-gel chemistry. Typically, subsequent calcination in air removes the organic template and reveals the porous inorganic network. A significant challenge for such coatings is the anisotropic shrinkage due to the volume contraction related to solvent evaporation, inorganic condensation, and template removal, affecting the final porosity as well as pore shape, size, arrangement, and accessibility. Here, we show that …

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An Imaging Mass Spectrometry Investigation Into The N-Linked Glycosylation Landscape Of Pancreatic Ductal Adenocarcinoma And The Development Of Associated Tools For Enhanced Glycan Separation And Characterization, Colin Mcdowell Dec 2022

An Imaging Mass Spectrometry Investigation Into The N-Linked Glycosylation Landscape Of Pancreatic Ductal Adenocarcinoma And The Development Of Associated Tools For Enhanced Glycan Separation And Characterization, Colin Mcdowell

MUSC Theses and Dissertations

The severity of pancreatic ductal adenocarcinoma (PDAC) is largely attributed to a failure to detect the disease before metastatic spread has occurred. CA19-9, a carbohydrate biomarker, is used clinically to surveille disease progression, but due to specificity challenges is not suitable for early discovery. As CA19-9 and other prospective markers are glycan epitopes, there is great clinical interest in understanding the glycobiology of pancreatic cancer. Unfortunately, few studies have been able to link glycosylation changes directly to pancreatic tumors and instead have focused on peripheral glycan alterations in the serum of PDAC patients. To address this gap in our understanding, …

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Groundwater Remediation Using Modified Biochar, Kers Ung-Watson, Ismail Abdulraheem, Nikki Tibayan, Suraj Pochampally Dec 2022

Groundwater Remediation Using Modified Biochar, Kers Ung-Watson, Ismail Abdulraheem, Nikki Tibayan, Suraj Pochampally

Undergraduate Research Symposium Posters

Biochar, a lightweight black residue made of carbon, has proved to be an effective adsorbent to remove TCE from groundwater. Not only is it an economical substitute for conventional adsorbents but it can be created by using a variety of organic materials. For this project, it will rely on walnut shell feedstock to create biochar as this had the best ability to adsorb TCE.

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Photocatalytic Anti-Markovnikov Hydroetherification Of Olefins, Kimberly A. Loyer Dec 2022

Photocatalytic Anti-Markovnikov Hydroetherification Of Olefins, Kimberly A. Loyer

Undergraduate Honors Theses

The development of olefin hydroetherification reactions via the addition of an alcohol nucleophile and hydrogen atom across an unsaturated carbon-carbon bond has remained a sought- after synthetic transformation. The formation of ethers via this methodology has traditionally required the use of transition metals and/or harsh conditions to catalyze the reaction and is challenging to make selective. However, the Nicewicz laboratory has since developed an anti- Markovnikov intramolecular hydroetherification of alkenols using photoredox catalysis. With the mechanism of this pivotal transformation—and of photoredox reactions in general—being largely unexplored mechanistically, the Hirschi lab implemented experimental 13C kinetic isotope effects (KIEs) and density …

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Development Of A Novel Ionic Liquid-Coated Adsorbent For Treating Emerging Contaminants In Recycled Water On The International Space Station, Madeline Carroll, Gabson Baguma, Savanna Vacek Dec 2022

Development Of A Novel Ionic Liquid-Coated Adsorbent For Treating Emerging Contaminants In Recycled Water On The International Space Station, Madeline Carroll, Gabson Baguma, Savanna Vacek

Undergraduate Research Symposium Posters

Synthesize at least 3 biobased ionic liquids. Optimize method for conducting liquid-liquid extractions. Analyze and quantify how much DMSO2 is removed by the ionic liquids. Coat biochar with the most effective biobased ionic liquids.

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Trapping And Cooling Of Ca+ For Cold Ion-Radical Collisions, Bernardo Gutierrez Dec 2022

Trapping And Cooling Of Ca+ For Cold Ion-Radical Collisions, Bernardo Gutierrez

Undergraduate Research Symposium Posters

Free radicals are molecules that contain an unpaired valence electron which induces high reactivity. Ion radical reactions are typically exothermic and have low (or zero) activation energy. It is for these reasons that ion-radical reactions are believed to dominate in interstellar clouds where temperatures hover around 3-10K. State-to-state measurements require precision control of both reactants.

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Molecular Insights Into The Redox Of Atmospheric Mercury Through Laser Spectroscopy, Rongrong Wu Cohen Dec 2022

Molecular Insights Into The Redox Of Atmospheric Mercury Through Laser Spectroscopy, Rongrong Wu Cohen

Theses and Dissertations

The widespread pollution of mercury motivates research into its atmospheric chemistry and transport. Gaseous elemental mercury (Hg(0)) dominates mercury emission to the atmosphere, but the rate of its oxidation to mercury compound (Hg(II)) plays a significant role in controlling where and when mercury deposits to ecosystems. Atomic bromine is regarded as the main oxidant for Hg(0) oxidation, known to initiate the oxidation via a two-step process in the atmosphere – formation of BrHg (R1) and subsequent reactions of BrHg with abundant free radicals Y, i.e., NO2, HOO, etc. (R2), where the reaction of BrHg +Y could also lead to the …

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The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements, Niroshani S. Abeynayake Dec 2022

The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements, Niroshani S. Abeynayake

Theses and Dissertations

Incorporation of silicon in the ligand backbone would yield electron-rich metal complexes upon coordination to transition metal complexes. The coordination chemistry of semirigid benzyl phosphines bearing a single or multiple phosphorus atoms and varying number of Si−H moieties has gained interest in recent years. This dissertation focuses on synthesizing silyl and germyl transition metal complexes of groups 9 and 10. Chapter II presents the synthesis of a family of four coordinated 14-electron rhodium complexes. The newly synthesized complexes were characterized in solution by multinuclear NMR spectroscopy and in the solid-state by single-crystal X-ray diffraction. These d6 complexes possess sawhorse …

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Enhanced Neurologic Concept Recognition Using A Named Entity Recognition Model Based On Transformers, Sima Azizi, Daniel B. Hier, Donald C. Wunsch Dec 2022

Enhanced Neurologic Concept Recognition Using A Named Entity Recognition Model Based On Transformers, Sima Azizi, Daniel B. Hier, Donald C. Wunsch

Chemistry Faculty Research & Creative Works

Although Deep Learning Has Been Applied to the Recognition of Diseases and Drugs in Electronic Health Records and the Biomedical Literature, Relatively Little Study Has Been Devoted to the Utility of Deep Learning for the Recognition of Signs and Symptoms. the Recognition of Signs and Symptoms is Critical to the Success of Deep Phenotyping and Precision Medicine. We Have Developed a Named Entity Recognition Model that Uses Deep Learning to Identify Text Spans Containing Neurological Signs and Symptoms and Then Maps These Text Spans to the Clinical Concepts of a Neuro-Ontology. We Compared a Model based on Convolutional Neural Networks …

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The Design, Synthesis, And Investigation Into Small Molecule Modulators Of The Src Homology 2 Domain-Containing Inositol 5’-Phosphatase (Ship), Shea Thomas Meyer Dec 2022

The Design, Synthesis, And Investigation Into Small Molecule Modulators Of The Src Homology 2 Domain-Containing Inositol 5’-Phosphatase (Ship), Shea Thomas Meyer

Dissertations - ALL

The PI3K pathway is a major cell signaling pathway that influences survival and longevity in eukaryotic cells. Abnormal signaling of this pathway has been implicated in a number of disorders, including Alzheimer's disease and cancer. The PI3K pathway utilizes the inositolphospholipid PI(3,4,5)P3 as a key secondary messenger in the transmission of signals from outside the cell to the nucleus. The SRC Homology 2 containing Inositol 5’-Phosphatase (SHIP) also plays a key role in the PI3K pathway, mediating hydrolysis of the inositol phospholipid PI(3,4,5)P3 to PI(3,4)P2. Early testing has shown modulation of SHIP activity through the use of small molecule modulators …

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Free Radical-Based Sequencing For Native Top-Down Mass Spectrometry, Carolina Rojas Ramírez, Rayan Murtada, Jinshan Gao, Brandon T. Ruotolo Dec 2022

Free Radical-Based Sequencing For Native Top-Down Mass Spectrometry, Carolina Rojas Ramírez, Rayan Murtada, Jinshan Gao, Brandon T. Ruotolo

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Native top-down proteomics allows for both proteoform identification and high-order structure characterization for cellular protein complexes. Unfortunately, tandem MS-based fragmentation efficiencies for such targets are low due to an increase in analyte ion mass and the low ion charge states that characterize native MS data. Multiple fragmentation methods can be integrated in order to increase protein complex sequence coverage, but this typically requires use of specialized hardware and software. Free-radical-initiated peptide sequencing (FRIPS) enables access to charge-remote and electron-based fragmentation channels within the context of conventional CID experiments. Here, we optimize FRIPS labeling for native top-down sequencing experiments. Our labeling …

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Computer Simulation Of The Light Absorption Band Of The Jumping Spider Isorhodopsin, Noah Zoldak Dec 2022

Computer Simulation Of The Light Absorption Band Of The Jumping Spider Isorhodopsin, Noah Zoldak

Honors Projects

In order to simulate the photoisomerization of the 9-cis Jumping Spider Isorhodopsin (JSiR-1) it is necessary to first simulate its light-absorption band. Here we report on the absorption band simulated using protein models constructed using the advanced Automatic Rhodopsin Modeling (a-ARM) program. A population of S0 models was created and the corresponding S0 to S1 transitions were determined for each member of the resulting population. The calculation resulted in a Gaussian plot showing that the wavelength of the absorption maximum of 560 nm (a violet color) that is consistent, but red-shifted, with respect the experimentally observed value.

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Standardization Of A Latent Blood Visualizer Based Upon Dna Degradation, Kailey M. Van 'T Hoff Dec 2022

Standardization Of A Latent Blood Visualizer Based Upon Dna Degradation, Kailey M. Van 'T Hoff

Honors Projects

Latent blood visualizers have been used in forensic science since 1937 beginning with Luminol. These visualizers through different types of reactions react with trace amounts of blood that cannot be seen with the naked human eye. These different reactions produce color that can then be seen by examiners. The four types of latent blood visualizers that were compared is luminol, leuco crystal violet, fluorescein, and bluestar. Luminol and bluestar use chemiluminescence, fluorescein uses florescent, and leuco crystal violet uses oxidation to react with iron in hemoglobin. At crime scenes when blood is detected which includes with the blood visualizers the …

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Partial Coalescence Of Cdse/Cds Core/Shell Nanocrystals, Jordyn Wray Dec 2022

Partial Coalescence Of Cdse/Cds Core/Shell Nanocrystals, Jordyn Wray

Honors Program Theses and Research Projects

Quantum dots are semiconductor nanocrystals that are a few nanometers in size that have different optical and electrical properties depending on size and shape. Some applications that quantum dots are used for, include, lasers, quantum computing, and solar cells. The goal of the research was to fuse cadmium selenide, cadmium sulfide (CdSe/CdS) core shells into dimers to increase the communication between particles in these applications. The CdSe were synthesized to 3 nm cores. Various procedures were used for CdSe/CdS synthesis, but the best performing sample contained 5 nm particles in diameter and a promising size for fusion. A metal salt …

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Hydrogen Bonding In Small Model Peptides; The Dft And Mp2 Study, Gracie Smith, Martina Kaledin Dec 2022

Hydrogen Bonding In Small Model Peptides; The Dft And Mp2 Study, Gracie Smith, Martina Kaledin

Symposium of Student Scholars

Formamide is a small model compound for the study of the peptide bond. The peptide bond links amino acids together, specifies rigidity to the protein backbone, and includes the essential docking sites for hydrogen-bond-mediated protein folding and protein aggregation, namely, the C=O acceptor and the N-H donor parts. Therefore, the infrared C=O (amide-I) and N-H (amide-A) vibrations provide sensitive and widely used probes into the structure of peptides. This computational chemistry work, we study hydrogen bonds in formamide dimer isomers. We evaluate the accuracy of the density functional theory (DFT) and many-body perturbation theory to the 2nd order (MP2) …

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Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes, Perry Skiouris, Ally Kisiel, Valentino Sorto, Julia Mauro, Graham Collier Dec 2022

Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes, Perry Skiouris, Ally Kisiel, Valentino Sorto, Julia Mauro, Graham Collier

Symposium of Student Scholars

Electrochromic materials have found widespread use in consumer electronics, energy saving windows, and military applications. They contain unique electronic properties allowing them to undergo a color change in a redox reaction. One classification of these molecules is known as anodically coloring electrochromes (ACEs). When in solution, these compounds are transmissive in the neutral (ground) state and absorb visible light upon oxidation, by the formation of a radical cation, thus making them colored. The focus of this study is the electronic transitions of this radical cation and how chemical modifications to the structures produce a variable color profile. To design prospective …

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