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Surface Chemistry And Spectroscopic Studies Of Enzymatic, Non-Enzymatic Molecules And Their Applications, Shiv K. Sharma

Open Access Dissertations

The content of this thesis is an investigation into physicochemical, photophysical, and interfacial properties of β-galactosidase, a crucial enzyme, its conjugate with CDs, interaction of β-galactosidase with X-gal, and surface chemistry and spectroscopic study of toxins, Cholera toxin B (CTB) and Fumonisin B1 (FB1). The objective of the work was to understand the surface chemistry behavior of the important enzyme, conjugates and toxins in a model systems representing vaguely cell membrane environments, to prove the activity of the deposited enzyme, its conjugate, and toxins in a form of the monolayer. We also studied the effect of green LED light on …

Mole Street Journal, December 2018, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Computational Quantum Chemistry Studies Of The Interactions Of Amino Acids Side Chains With The Guanine Radical Cation., Edward Acheampong

Electronic Theses and Dissertations

Guanine is generally accepted as the most easily oxidized DNA base when cells are subjected to ionizing radiation, photoionization or photosensitization. At pH 7, the midpoint reduction potential is on the order of 0.2 – 0.3 V higher than those of the radicals of e.g. tyrosine, tryptophan cysteine and histidine, so that the radical “repair” (or at least, a thermodynamically favorable reaction) involving these amino acids is feasible. Computational quantum studies have been done on tyrosine, tryptophan, cysteine and histidine side chains as they appear in histones. Density functional theory was employed using B3LYP/6-31G+ (d, p) basis set to study …

We Are ... Marshall, October 17, 2018, Office Of Marshall University Communications

We Are ... Marshall: the Newsletter for Marshall University 1999-2023

No abstract provided.

The Antelope, University Of Nebraska At Kearney

The Antelope

No abstract provided.

Mole Street Journal, October 2018, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Study Abroad Gives Croft Students Experience Of A Lifetime, Shea Stewart

University of Mississippi News

Semester, year overseas creates global citizens out of institute's students

Chem 360-001 Environmental Chemistry, Alexei Khalizov

Chemistry, Environmental and Forensic Science Syllabi

No abstract provided.

Synthesis And Evaluation Of Densely-Functionalized Troponoids, Danielle R. Hirsch

Dissertations, Theses, and Capstone Projects

Herein, we document our efforts to expand the scope of troponoid synthetic methodology towards densely-substituted scaffolds. This body of work has focused primarily on an oxidopyrylium cycloaddition/ring-opening strategy for the synthesis and biochemical evaluation of troponoids for assistance in a variety of medicinal chemistry studies. In Chapter 1, we outline the use of this synthetic strategy in the profiling of a library of synthetic αHTs against an aminoglycoside antibiotic resistance enzyme known as aminoglycoside-2’’-O-nucleotidyltransferase [ANT(2’’)-Ia]. Enzymatic mechanistic insights have been gleaned from an assessment of troponoid/antibiotic synergistic potential. In particular, two synthetic constructs were identified as promising antibiotic adjuvant candidates, …

Sources Of Students’ Difficulties In Learning Chemistry, David F. Treagust, Reinders Duit, Martina Nieswandt

Administration and Staff Articles and Research

Chemistry is a difficult subject to teach and to learn at both secondary and tertiary levels. Major learning difficulties are due to the particular views of chemistry phenomena that in many ways contradict intuitive and everyday views of the learners. As a result, major misunderstandings occur when students try to comprehend chemical explanations within the framework of their pre-instructional conceptions. This paper describes research findings on students’ pre-instructional conceptions in the domain of chemistry and on attempts to guide students from their conceptions to the core ideas of chemistry. Rather than providing an overview of students’ conceptions in various topics, …

Mole Street Journal, August 2018, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Gas-Phase And Condensed-Phase Studies Of Small Reactive Intermediates, Christopher William Haskins

Open Access Dissertations

Nitriles are an integral functional group in many chemical industries. A new methodology for the dehydration of amides to nitriles has been developed using a palladium catalyst. The reaction conditions are robust and able to tolerate a wide variety of functional groups and substrates. The substrate scope can be broken into 4 main types of substrates including: alkyl, aromatic, cinnamic, and α, β, δ, γ-unsaturated amides. Mechanistically, the amide goes through a water exchanging mechanism to generate acetamide in equal parts to the nitrile. Cyclopropanols are important precursors for the generation of beta-carbonyl radicals. In the presence of a single-electron …

The Analysis And Conservation Of A 1930s Theatrical Make-Up Kit, Mary Wilcop

Art Conservation Master's Projects

A 1930s theatrical makeup kit in the collection the Buffalo Museum of Science was analyzed and treated at the Garman Family Art Conservation Department at Buffalo State College. The kit, comprised of a tinplated-steel L. Leichner expandable makeup box, was packed tightly with 105 individual items including: greasepaints; paper, metal, and glass containers of powder- and cream-based cosmetics; wool crepe hairs; makeup-stained cotton balls; several plastic objects; and paper documents. The kit was gifted in 1983, where it had remained since in storage. Approaching treatment began with research into the history of theatrical cosmetics to lend context to the historical …

Conformationally-Controlled Late-Stage Modifications For Sar Studies Of The C-3-Glcp Moiety Of Ipomoeassin F, Lucas Whisenhunt

Graduate Theses and Dissertations

The resin glycoside, ipomoeassin F has been shown to be extremely potent against multiple cancer lines (IC50 = 4.2-36 nM). However, the mechanism of action of this potent and complex natural product is still not fully understood. The α,β-unsaturated esters of the glucosyl moiety have been shown to be vital for the overall cytotoxicity of ipomoeassin F. Nevertheless, the importance of the tigloyl ester of the glucosyl moiety is still largely unknown. This work aimed to study the pharmacophore importance of the tigloyl ester by creating, an efficient, scalable, and flexible synthesis route for various analogs. The 18-linear step synthesis …

Reverse Flotation Separation Of Fluorite From Calcite: A Novel Reagent Scheme, Jianjun Wang, Zihan Zhou, Yuesheng Gao, Wei Sun, Yuehua Hu, Zhiyong Gao

Michigan Tech Publications, Part 1

Fluorite (CaF₂), as an important strategic mineral source, is usually separated from calcite by the common froth flotation method, but this separation is still not selective enough. The development of a selective collector and/or depressant is the key to achieving high selective separation. 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP or H₄L) is widely used as an environmentally friendly water treatment reagent due to its low cost and excellent anti-scaling performance in an aqueous solution. In this study, a novel reagent scheme was developed using HEDP as a fluorite depressant and sodium oleate (NaOL) as a calcite collector for the …

Moving Beyond Alpha: A Primer On Alternative Sources Of Single-Administration Reliability Evidence For Quantitative Chemistry Education Research, Regis Komperda, Thomas C. Pentecost, Jack Barbera

Chemistry Faculty Publications and Presentations

This methodological paper examines current conceptions of reliability in chemistry education research (CER) and provides recommendations for moving beyond the current reliance on reporting coefficient alpha (α) as reliability evidence without regard to its appropriateness for the research context. To help foster a better understanding of reliability and the assumptions that underlie reliability coefficients, reliability is first described from a conceptual framework, drawing on examples from measurement in the physical sciences; then classical test theory is used to frame a discussion of how reliability evidence for psychometric measurements is commonly examined in CER, primarily in the form of single-administration reliability …

Evaluation Of Trace-Metal And Isotopic Records As Techniques For Tracking Lifetime Movement Patterns In Fishes, Jennifer E. Granneman

USF Tampa Graduate Theses and Dissertations

The focus of this work was on the use of otolith microchemistry and fish eye lens chemical profiles to measure fish movement and provided indirect support for the use of otolith microchemistry to examine exposure to crude oil. Chapter 1 provides an introduction to the applications of otolith microchemistry and eye lens isotopic profiles. In the second chapter, which examined associations between metal exposure and lesion formation in fishes collected after the Deepwater Horizon (DWH) oil spill, I did not observe any change in oil-associated metal concentrations in otoliths coinciding with the timing of the DWH oil spill. This suggests …

Chemistry, Saint Mary's College Of California

Undergraduate Academic Catalog

No abstract provided.

Deciphering The Mechanism Of O2 Reduction With Electronically Tunable Non-Heme Iron Enzyme Model Complexes, Roshaan Surendhran, Alexander A. D'Arpino, Bao Y. Sciscent, Anthony F. Cannella, Alan E. Friedman, Samantha N. Macmillan, Rupal Gupta, David C. Lacy

Publications and Research

A homologous series of electronically tuned 2,20,200-nitrilotris(N-arylacetamide) pre-ligands (H3LR) were prepared (R ¼ NO2, CN, CF3, F, Cl, Br, Et, Me, H, OMe, NMe2) and some of their corresponding Fe and Zn species synthesized. The iron complexes react rapidly with O2, the final products of which are diferric mu-oxo bridged species. The crystal structure of the oxidized product obtained from DMA solutions contain a structural motif found in some diiron proteins. The mechanism of iron mediated O2 reduction was explored to the extent that allowed us to construct an empirically consistent rate law. A Hammett plot was constructed that enabled …

Mole Street Journal, June 2018, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Deconvoluting The Effects Of Surface Chemistry And Nanoscale Topography: Pseudomonas Aeruginosa Biofilm Nucleation On Si-Based Substrates, Jing Zhang, Jingling Huang, Carmen Say, Robert L. Dorit, Kate Queeney

Chemistry: Faculty Publications

Hypothesis

The nucleation of biofilms is known to be affected by both the chemistry and topography of the underlying substrate, particularly when topography includes nanoscale (nm) features. However, determining the role of topography vs. chemistry is complicated by concomitant variation in both as a result of typical surface modification techniques. Analyzing the behavior of biofilm-forming bacteria exposed to surfaces with systematic, independent variation of both topography and surface chemistry should allow differentiation of the two effects.

Experiments

Silicon surfaces with reproducible nanotopography were created by anisotropic etching in deoxygenated water. Surface chemistry was varied independently to create hydrophilic (OH- terminated) …

Using Quenching To Detect Corrosion On Sculptural Metalwork: A Real-World Application Of Fluorescence Spectroscopy, Cory Hensen, Tami Lasseter Clare, Jack Barbera

Chemistry Faculty Publications and Presentations

Fluorescence spectroscopy experiments are a frequently taught as part of upper-division teaching laboratories. To expose undergraduate students to an applied fluorescence technique, a corrosion detection method, using quenching, was adapted from authentic research for an instrumental analysis laboratory. In the experiment, students acquire fluorescence spectra of sensing molecules in the presence of mock sculpture samples and discuss the condition of the sculptures based on the levels of soluble iron detected. This real-world-based experiment allows students the chance to engage with ongoing research and further understand the challenges with early detection of corrosion. Most students successfully completed the experiment, wrote a …

Characterization Of Protease-Activated Receptor (Par) Ligands: Parmodulins Are Reversible Allosteric Inhibitors Of Par1-Driven Calcium Mobilization In Endothelial Cells, Disha M. Gandhi, Mark W. Majewski, Ricardo Rosas Jr., Kaitlin Kentala, Trevor J. Foster, Eric Greve, Chris Dockendorff

Chemistry Faculty Research and Publications

Several classes of ligands for Protease-Activated Receptors (PARs) have shown impressive anti-inflammatory and cytoprotective activities, including PAR2 antagonists and the PAR1-targeting parmodulins. In order to support medicinal chemistry studies with hundreds of compounds and to perform detailed mode-of-action studies, it became important to develop a reliable PAR assay that is operational with endothelial cells, which mediate the cytoprotective effects of interest. We report a detailed protocol for an intracellular calcium mobilization assay with adherent endothelial cells in multiwell plates that was used to study a number of known and new PAR1 and PAR2 ligands, including an alkynylated version of the …

General Chemistry Student Attitudes And Success With Use Of Online Homework: Traditional- Responsive Versus Adaptive-Responsive, Michelle Richards-Babb, Reagan Curtis, Betsy Ratcliff, Abhik Roy, Taylor Mikalik

Clinical and Translational Science Institute

We investigated whether use of an adaptive-responsive online homework system (OHS) that tailors homework to students’ prior knowledge and periodically reassesses students to promote learning through practice retrieval has inherent advantages over traditional-responsive online homework. A quasi-experimental cohort control post-test-only design with nonequivalent groups and propensity scores with nearest neighbor matching (n = 6,114 pairs) was used. The adaptive system was found to increase the odds of a higher final letter grade for average, below average, and failing students. However, despite the learning advantages, students self-reported less favorable attitudes toward adaptive-responsive (3.15 of 5) relative to traditional-responsive OHS (3.31). Specific …

A Molecular Perspective For The Understanding Of Polymer‒Drug Interactions, Laura Isabel Mosquera Giraldo

Open Access Dissertations

Polymers are often used to stabilize amorphous drug formulations enabling the maintenance of high drug supersaturations. However, the molecular mechanism of stabilization is unclear, making the rational design of new polymers challenging. This research has focused on understanding the effectiveness of polymers to inhibit drug crystallization using experimental and computational modeling approaches. This thesis has six sections. The first section reviews the pharmaceutical significance of amorphous solid dispersions. The second section describes a study to evaluate the phase behavior of supersaturated drug solutions of telaprevir, a compound that undergoes glass-liquid phase separation when the amorphous solubility is exceeded. The third …

A Study About The Effect Of Addition Of Carbon Nanofibers On The Strain-Rate Sensitivity Of Thermoplastic Polymer Matrix Nanocomposites Manufactured By Ultrasonication Process, Rohit Tandon

All Theses

Thermoplastic polymers have been widely used in the industry due to their high toughness and impact resistance along with their remolding capabilities as compared to thermoset polymers, which also makes them an attractive choice for polymer composites. Many desirable features of thermoplastic polymers like ease of processing, low weight and cost, and corrosion resistance make thermoplastics a viable option for applications in the automotive, aerospace, sporting goods and many other industries. To further increase the mechanical, thermal and electrical properties of thermoplastic polymers, nanomaterials are added to the polymer matrix that can improve these properties at very low loading levels …

Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood

Graduate Theses/Dissertations

Springfield, MO is located on the Springfield Plateau physiographic province. The Springfield plateau contains a number of Mississippian aged units and is mainly capped by the Burlington-Keokuk Formation. The Burlington-Keokuk is a highly fossiliferous limestone with nodular and interbedded chert. Beneath the Burlington-Keokuk lies the Elsey, Reeds Spring, and Pierson Formations respectively which comprise the Springfield Plateau aquifer hydrostratigraphic unit. Within the Springfield Plateau aquifer, a well-developed karst system includes springs, sinkholes, and caves. The Springfield Plateau aquifer is the predominant source for springs and seeps in the Springfield area. The purpose of this study was to understand the differences …

Mass Upstream Dispersal Of Pelagic-Broadcast Spawning Cyprinids In The Rio Grande And Pecos River, New Mexico, Thomas P. Archdeacon, Stephen R. Davenport, Joshua D. Grant, Eileen B. Henry

Western North American Naturalist

Pelagic-broadcast spawning minnows are a reproductive guild of fishes, of which several species occur in the American Great Plains and Southwest. The eggs and larvae of these species drift laterally and downstream, with drift distances varying depending on channel conditions and flow. Persistence or recolonization of these species in upstream reaches must depend on retention of eggs and larvae or upstream dispersal of later life stages, otherwise net downstream displacement of eggs and larvae would result in upstream extirpations. However, only a few individuals of several species have been observed dispersing. Here, we describe 2 direct visual observations of the …

Mole Street Journal, April 2018, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

College Students Understanding On Spectroscopy Topic Using Stad Cooperative Learning Combined With Moodle, Ade Trisnawati, Surjani Wonorahardjo, Munzil Arief

Jurnal Pendidikan Sains

Spectroscopy is an abstract and difficult topic in chemistry. Students should be able to explain this concept. The purpose of this pre-experimental research was to explore the understanding of students about spectroscopy using STAD cooperative learning combined with Moodle. A sample of this study were 34 fifth-semester college students majoring at Chemistry studying at the University X. The results showed the students’ understanding on tools instrumentation and their functions on Raman spectroscopy, photometric titration method, the function of the components in IR spectrophotometer, compounds based on transition-absorbing electrons, and the basic principle of atomic spectroscopy material were low.