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Modeling Accuracy Matters: Aligning Molecular Dynamics With 2d Nmr Derived Noe Restraints, Milan Patel 2023 University of Connecticut

Modeling Accuracy Matters: Aligning Molecular Dynamics With 2d Nmr Derived Noe Restraints, Milan Patel

Honors Scholar Theses

Among structural biology techniques, Nuclear Magnetic Resonance (NMR) provides a holistic view of structure that is close to protein structure in situ. Namely, NMR imaging allows for the solution state of the protein to be observed, derived from Nuclear Overhauser Effect restraints (NOEs). NOEs are a distance range in which hydrogen pairs are observed to stay within range of, and therefore experimental data which computational models can be compared against. To that end, we investigated the effects of adding the NOE restraints as distance restraints in Molecular Dynamics (MD) simulations on the 24 residue HP24stab derived villin headpiece subdomain to …


Synthesis Of A Phenyl Substituted Zinc Dipyrrin Complex For The Purpose Of Analyzing Aromatic Substitutions On The Characteristics Of Compounds Of This Class, Kole Owen 2023 East Tennessee State University

Synthesis Of A Phenyl Substituted Zinc Dipyrrin Complex For The Purpose Of Analyzing Aromatic Substitutions On The Characteristics Of Compounds Of This Class, Kole Owen

Undergraduate Honors Theses

The field of photochemistry is as innovative in development as it is broad in application. However, utilization of energy from the sun’s electromagnetic radiation remains secondary to the combustion of fossil fuels for the global energy consumption. This is neither a sustainable nor renewable system, and it has contributed to a major decline in the health of our global environment as the greenhouse gases emission has led to an incline in global temperatures and ocean acidity. To develop effective ways to utilize solar energy, experimental effort is being directed towards the understanding of photosensitizers, molecules which absorb solar radiation and …


Molecular Evidence For The Export Of Terrigenous Organic Matter To The North Gulf Of Mexico By Solid-State 13C Nmr And Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Of Humic Acids, Sarah Ann Ware 2023 Old Dominion University

Molecular Evidence For The Export Of Terrigenous Organic Matter To The North Gulf Of Mexico By Solid-State 13C Nmr And Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Of Humic Acids, Sarah Ann Ware

Chemistry & Biochemistry Theses & Dissertations

Marine organic matter is mainly believed to originate from autochthonous organic matter, while terrigenous organic matter is assumed to be largely degraded prior to reaching the open ocean or more recently replaced by marine organic matter via a stripping process. Sediment samples along a transect extending from the Mississippi River Birdsfoot Delta to the Mississippi Canyon on the Louisiana continental shelf were examined by advanced analytical techniques, electrospray ionization coupled to a 12T Fourier transform ion cyclotron resonance mass spectrometer (ESI-FTICR-MS) and quantitative solid-state multiple cross polarization magic angle spinning (multi-CPMAS) 13C NMR in an effort to understand the …


Survey Of The Performance Of 5 Nm Gold Nanoparticles Within An Ssdna-Stabilized Biosensor For The Detection Of Hg2+, Madalyn Zagajowski 2023 Olivet Nazarene University

Survey Of The Performance Of 5 Nm Gold Nanoparticles Within An Ssdna-Stabilized Biosensor For The Detection Of Hg2+, Madalyn Zagajowski

Honors Program Projects

The formation of a fluorescent biosensor complex consisting of 5 nm diameter gold nanoparticles (AuNPs) and single-stranded DNA (ssDNA) was conducted using a low-cost, efficient binding method. The analytical potential for the complex to detect mercuric ions (Hg2+) in an aqueous solution was assessed through the collection of UV-vis and fluorescence spectrometry data for the AuNP-ssDNA complex. The researcher aimed to investigate this potential in case the nanoparticles formed utilizing this method were too small to result in detectable fluorescence. To eliminate this possibility, the complex synthesized from this specific method was qualitatively evaluated to determine if it …


Repeated Low-Level Blast Exposure Alters Urinary And Serum Metabolites, Austin Sigler, Jiandong Wu, Annalise Pfaff, Olajide Adetunji, Paul Ki-souk Nam, Donald James, Casey Burton, Honglan Shi 2023 Missouri University of Science and Technology

Repeated Low-Level Blast Exposure Alters Urinary And Serum Metabolites, Austin Sigler, Jiandong Wu, Annalise Pfaff, Olajide Adetunji, Paul Ki-Souk Nam, Donald James, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Repeated exposure to low-level blast overpressures can produce biological changes and clinical sequelae that resemble mild traumatic brain injury (TBI). While recent efforts have revealed several protein biomarkers for axonal injury during repetitive blast exposure, this study aims to explore potential small molecule biomarkers of brain injury during repeated blast exposure. This study evaluated a panel of ten small molecule metabolites involved in neurotransmission, oxidative stress, and energy metabolism in the urine and serum of military personnel (n = 27) conducting breacher training with repeated exposure to low-level blasts. The metabolites were analyzed using HPLC—tandem mass spectrometry, and the Wilcoxon …


Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali 2023 University of Texas at Tyler

Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali

Chemistry Theses

The production of cutting-edge materials, the development of novel medications, drug delivery systems, technological advancements, and biosynthesizing all depend on molecular building blocks. Proteins are required for the creation of intricate, well-organized structures, and coiled-coil protein domains are vital subunits for the oligomerization of protein complexes, gene expression, and the structural components of biological materials. The numerous interactions between a wide variety of amino acids make it difficult to assemble protein complexes with a particular shape. In the current study, we successfully designed and synthesized four different 32-residue peptides, each of which had two modified amino azide residues. These peptides …


Surface Characterization Of Mixed-Mode Adsorbents Using Bet C-Constant Energy Scale, Dinah C. Lee 2023 Seton Hall University

Surface Characterization Of Mixed-Mode Adsorbents Using Bet C-Constant Energy Scale, Dinah C. Lee

Seton Hall University Dissertations and Theses (ETDs)

Mixed-mode chromatography is a chromatographic method in which solutes interact with stationary phase through more than one interaction mode or mechanism. It is because of these multiple complex interactions, which makes it difficult to predict chromatographic behavior of analytes on Mixed-mode columns. In order to fully understand the retention mechanisms on Mixed-mode columns, the packing material properties must be well characterized since each characteristic may contribute to the overall chromatographic performance of the column. Many non-chromatographic and chromatographic techniques are available to characterize and compare Mixed-mode columns in terms of their interaction abilities, retentivity, surface chemistry, chemical properties and geometry. …


Survey Of The Performance Of 5 Nm Gold Nanoparticles Within An Ssdna-Stabilized Biosensor For The Detection Of Hg2+, Madalyn Zagajowski 2023 Olivet Nazarene University

Survey Of The Performance Of 5 Nm Gold Nanoparticles Within An Ssdna-Stabilized Biosensor For The Detection Of Hg2+, Madalyn Zagajowski

Scholar Week 2016 - present

The formation of a fluorescent biosensor complex consisting of 5 nm diameter gold nanoparticles (AuNPs) and single-stranded DNA (ssDNA) was conducted using a low-cost, efficient binding method. Furthermore, we assessed the analytical potential for the complex to detect mercury ions (Hg2+) in an aqueous solution upon collection of UV-vis and fluorescence spectrometry data for the AuNP-ssDNA complex. We aimed to investigate this potential due to the possibility that the nanoparticles formed utilizing this method would produce nanoparticles of too small a size to result in detectable fluorescence, thus the complex synthesized from this specific method was qualitatively evaluated …


New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao 2023 Department of Chemistry and Industrial Chemistry, Faculty of Pure and Applied Sciences, Kwara State University Malete, Kwara State, Nigeria

New Alkyd Resins From Underutilized Indigenous Seed Oils: Synthesis And Characterization, Aliru O. Mustapha, Hakeem B. Ayoku, Halimah A. Amao

Karbala International Journal of Modern Science

The underutilization of sesame (Sesamum indicum L.), sweet almond (Prunus amygdalus), and jatropha (Jatropha curcas) seeds indicates a significant resource waste. Nine different varieties of 25% (short), 40% (medium), and 60% (long) alkyd resins were produced from the cross-section of drying, semi-drying, and non-drying oils. A large amount of conversion occurred, with the extent of the reaction (Pav) decreasing as time progressed and the corresponding increase in alkyds' average degree of polymerization (Dp) showing synthesized alkyds. Surface drying from the set-to-dry and dry-through periods climaxed at 2 hours for all the alkyds. Except for alkali, synthesized alkyd resins demonstrated outstanding …


Mapping Per- And Polyfluoroalkyl Substances (Pfas) In South Carolina Surface Waters: Are There Hotspots?, Thomas C. Geiger 2023 University of South Carolina - Columbia

Mapping Per- And Polyfluoroalkyl Substances (Pfas) In South Carolina Surface Waters: Are There Hotspots?, Thomas C. Geiger

Senior Theses

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in consumer products for their unique chemical properties. PFAS compounds are resistant to water, oil, heat, and grease, making them useful for a wide variety of everyday items such as non-stick cooking pans, food packaging, electronics, carpets, upholstery, paints, adhesives, and personal care products.1 The resilient nature of PFAS has made these compounds immensely popular with consumers but has since been considered a potential environmental and public health hazard for their ability to bioaccumulate and for their stability in the environment. More than 6000 PFAS have been discovered in the …


The Love Collection Of Chinese Wall Paintings, Donglin Chen 2023 Trinity College

The Love Collection Of Chinese Wall Paintings, Donglin Chen

Senior Theses and Projects

The Chinese Fresco Painting (accession #1951.230) at the Wadsworth Atheneum Museum of Art is a problematic work. The museum registration document showed that this wall painting is thought to have been painted during the Ming dynasty, ruling from 1368 to 1644. It may depict the Goddess of Sons and Grandsons, Zisun Niangniang. However, this is unprovenanced and unresearched. In this paper, connoisseurship analysis and scientific examination of the painting are carried out to elucidate the mystery of this Chinese mural. This study attempted to confirm the Ming Dynasty dating of this painting by demonstrating stylistic affinities between it and other …


Quantitation Of Female Newt Tetrodotoxin Concentrations And Their Impact In The Newt-Garter Snake Evolutionary Arms Race, Anna Frey, david green dr., lee kats dr., gary bucciarelli dr. 2023 Pepperdine University

Quantitation Of Female Newt Tetrodotoxin Concentrations And Their Impact In The Newt-Garter Snake Evolutionary Arms Race, Anna Frey, David Green Dr., Lee Kats Dr., Gary Bucciarelli Dr.

Seaver College Research And Scholarly Achievement Symposium

As this work is not yet published, the authors have requested the removal of the abstract.


The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus 2023 University of Nebraska-Lincoln

The Concentration Of Heavy Metals In Lincoln Nebraska's Tap Water, Evan Neuhaus

Honors Theses

Heavy metals are commonplace in nature, and are typically found in scarce quantities in all drinking sources. However, in high enough concentrations, they can have a myriad of negative health effects. This study seeks to find the concentrations of such metals in the Lincoln water supply utilizing the resources of the Water Center at the University of Nebraska at Lincoln. To test for discrete concentrations of trace elements, a method of using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was implemented. ICP-MS uses plasma to ionize and atomize a sample which is then filtered into a series of cones into a …


Investigation Of Unexpected Purple Substance Extracted From Newsprint Paper [Poster], Raquel Wilhelm, Shoshanna Coon, Kirk Manfredi 2023 University of Northern Iowa

Investigation Of Unexpected Purple Substance Extracted From Newsprint Paper [Poster], Raquel Wilhelm, Shoshanna Coon, Kirk Manfredi

Research in the Capitol

In an attempt to extract a green dye from newsprint advertisements, it was serendipitously discovered that a purple substance can be extracted from newsprint paper using methanol or acetic acid. Further investigations involving blank newsprint paper showed that the purple substance was a part of the paper itself rather than a component of the ink in the advertisements. Soxhlet extraction was used on the blank newspaper print to obtain the compound. Using different analytical instruments, characteristics of the compound can be determined such as the elemental composition, molar mass, and structure. The ultimate goal is to determine the compound and …


Use Of Electrochemical Techniques And Statistical Analysis To Investigate The Pitting Probability Of Copper, Sina Matin 2023 The University of Western Ontario

Use Of Electrochemical Techniques And Statistical Analysis To Investigate The Pitting Probability Of Copper, Sina Matin

Electronic Thesis and Dissertation Repository

The development of a safe permanent disposal plan is essential for the long-term disposal of used fuel bundles. Nuclear Waste Management Organization (NWMO) has been investigating the deep geologic disposal of nuclear waste which offers the optimum passive safety system with a negligible probability of release of radionuclides into the environment.

The proposed used fuel containers (UFC) for the permanent disposal of high-level nuclear waste in Canada is comprised of a carbon steel vessel coated with a 3 mm corrosion-resistant copper layer deposited using a combination of electrodeposition and cold spray deposition. Although copper is often considered to be thermodynamically …


Characterization Of Deposited Copper Oxide Films On Copper Substrates, Millicent Castillo 2023 The University of Western Ontario

Characterization Of Deposited Copper Oxide Films On Copper Substrates, Millicent Castillo

Electronic Thesis and Dissertation Repository

The deposition of copper oxide films on copper substrates was investigated by the electrochemical, thermal, and hydrothermal oxidation of copper. The formed oxides were characterized using various surface analytical techniques to determine the film’s morphology, composition, and thickness. The results show that by growing oxides electrochemically, a duplex layer composing of CuO and Cu2O film was formed on the copper surface, having characteristics of being porous and possessing needle-like structures. An oxide film composed of CuO and Cu2O, which shows minimal porosity and possess mixtures of crystalline and non-crystalline structures, is formed on the copper surface …


Development Of An Lcms Method To Detect And Quantify Curcumin In A Novel Oral Formulation Of Turmeric, Brandon Renninger 2023 Roseman University of Health Sciences

Development Of An Lcms Method To Detect And Quantify Curcumin In A Novel Oral Formulation Of Turmeric, Brandon Renninger

Annual Research Symposium

No abstract provided.


Inducible Nitric Oxide Synthase Embedded In Alginate/Polyethyleneimine Hydrogel As A New Platform To Explore No-Driven Modulation Of Biological Function, Shaimaa Maher, Lauren A. Smith, Celine A. El-Khoury, Haitham F. Kalil, Khalid Sossey-Alaoui, Mekki Bayachou 2023 Cleveland State University

Inducible Nitric Oxide Synthase Embedded In Alginate/Polyethyleneimine Hydrogel As A New Platform To Explore No-Driven Modulation Of Biological Function, Shaimaa Maher, Lauren A. Smith, Celine A. El-Khoury, Haitham F. Kalil, Khalid Sossey-Alaoui, Mekki Bayachou

Chemistry Faculty Publications

Nitric oxide (NO), a small free radical molecule, turned out to be pervasive in biology and was shown to have a substantial influence on a range of biological activities, including cell growth and apoptosis. This molecule is involved in signaling and affects a number of physiologic functions. In recent decades, several processes related to cancer, such as angiogenesis, programmed cell death, infiltration, cell cycle progression, and metastasis, have been linked with nitric oxide. In addition, other parallel work showed that NO also has the potential to operate as an anti-cancer agent. As a result, it has gained attention in cancer-related …


Nanoscale Imaging Of Electrocatalytic Nanomaterials By High-Resolution Scanning Electrochemical Microscopy, Xiang Wang 2023 The Graduate Center, City University of New York

Nanoscale Imaging Of Electrocatalytic Nanomaterials By High-Resolution Scanning Electrochemical Microscopy, Xiang Wang

Dissertations, Theses, and Capstone Projects

Numerous insights of the structure–electrochemical activity relationship of nanocatalysts have been obtained by using macroscopic electrochemical measurements over the last several decades. However, signals measured by large electrodes are inevitably averaged out of many nanocatalysts, non-uniformed sizes, uneven morphologies, and multiple crystallographic facets. Over the last ten years, Scanning Electrochemical Microscopy (SECM) has advanced electrochemical measurements toward micro- to nanoscale level at a high spatial resolution. The advantages of using nanoelectrode in SECM include fast mass transfer of reactive species, dominated radial diffusion pattern, small double layer capacitance and small RC constant. In this thesis, high-resolution SECM is applied to …


Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano 2023 The Graduate Center, City University of New York

Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano

Dissertations, Theses, and Capstone Projects

Enzyme-responsive materials have been well explored, particularly as therapeutic and diagnostic agents. In this thesis we demonstrate that anionic self-assembling peptides can be utilized as delivery vehicles for metal-based hydrophobic payloads. The tunability of the system is highlighted as well as the increase in cytotoxicity and selectivity in vitro. The rapid degradation of peptides in cell media may lead to the formation of new peptide-drug bioconjugates with increased activity and selectivity. The physiological stability of these peptide delivery vehicles has been optimized by capping the N-terminus with an acetyl group. This simple backbone modification was shown to not prevent self-assembly, …


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