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Surface Chemistry And Spectroscopy Of Human Insulin Langmuir Monolayer, Sheba Johnson

Open Access Dissertations

The focus of this thesis can be categorized as study of two molecules, namely human insulin and carbon dots at 1) air-water interface as a Langmuir monolayer and 2) in solution. Aggregation of proteins into amyloids has been related to several diseases like Alzheimer’s, Parkinson’s and Amyloidosis. Human insulin was chosen as a model protein to study fibrillation of the proteins. Effect of carbon dots on the rate of human insulin fibrillation was examined through spectroscopic techniques and imaging. Both human insulin and carbon dots were examined at air-water interface as a Langmuir monolayer. The conformation of human insulin in …

Mole Street Journal, December 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Kinetic Experimental And Modeling Studies On Iron-Based Catalysts Promoted With Lanthana For The High-Temperature Water-Gas Shift Reaction Characterized With Operando Uv-Visible Spectroscopy And For The Fischer-Tropsch Synthesis, Basseem Bishara Hallac

Theses and Dissertations

The structural and functional roles of lanthana in unsupported iron-based catalysts for the high-temperature water-gas shift reaction and Fischer-Tropsch synthesis were investigated. The performance of the catalysts with varying lanthana contents was based on their activity, selectivity, and stability. With regard to the former reaction, extent of reduction of the iron in Fe2O3/Cr2O3/CuO/La2O3 water-gas shift catalysts is a key parameter that was characterized using UV-visible spectroscopy. Minor addition of lanthana (<0.5 wt%) produces more active and stable catalysts apparently because it stabilizes the iron-chromium spinel, increases the surface area of the reduced catalysts, enhances the reduction of hematite to the magnetite active phase, and facilitates the adsorption of CO on the surface of the catalyst modeled by an adsorptive Langmuir-Hinshelwood mechanism. Statistical 95% confidence contour plots of the adsorption equilibrium constants show that water adsorbs more strongly than CO, which inhibits the reaction rate. A calibration curve that correlates the oxidation state of surface iron domains to normalized absorbance of visible light was successfully generated and applied to the water-gas shift catalysts. UV-visible studies indicated higher extent of reduction for surface Fe domains for the catalysts promoted with 1 wt% of lanthana and showed potential to be a more convenient technique for surface chemistry studies than X-ray absorption near edge spectroscopy (XANES). Lanthana addition to iron-based Fischer-Tropsch catalysts enhances the olefin-to-paraffin ratio, but decreases their activity, stability, and selectivity to liquid hydrocarbons. Adding lanthana at the expense of potassium reduces the water-gas shift selectivity and enhances the activity and stability of the catalysts. Finally, a model that simulates heat and mass transfer limitations on the particle scale for the Fischer-Tropsch reaction applicable at lab-scale suggests optimal operating and design conditions of 256°C, 30 bar, and 80 mirons are recommended for higher selectivity to liquid hydrocarbons. The model considers pressure drop, deactivation, pore diffusion, film heat transfer, and internal heat transfer when solving for the optimal conditions, and maps them as functions of design variables. This model can be up-scaled to provide guidance for optimal design of commercial-size reactors.

Sign Me Up! Determining Motivation For High School Chemistry Students Enrolling In A Second Year Chemistry Course, Nilda N. Camarena

Theses and Dissertations - UTB/UTPA

A sample of 108 Pre-AP Chemistry students in Texas participated in a study to determine motivational factors for enrolling in AP Chemistry and University Chemistry. The factors measured were academic attitude, perceptions of chemistry, confidence level in chemistry, and expectations/experiences in the chemistry class. Students completed two questionnaires, one at the beginning of the year and one at the end. Four high school campuses from two school districts in Texas participated. Two campuses were traditional high schools and two were smaller magnet schools. The results from this study are able to confirm that there are definite correlations between academic attitudes, …

Um Vice Chancellor Honored As Prestigious Aaas Fellow, Mitchell Diggs

University of Mississippi News

Alice Clark cited for research achievements, service to National Institutes of Health

Evaluation And Application Of Instruments Measuring Spatial Ability And Attitude For College Chemistry Students, Xiaoying Xu

USF Tampa Graduate Theses and Dissertations

Student performance in college chemistry courses remains a concern for educators seeking to help improve the future STEM workforce. Besides math ability and prior chemistry knowledge, spatial ability and attitude toward chemistry have been considered as important factors influencing college chemistry performance. This work includes five studies and uses data collected from instruments to examine the relationships of these two factors - spatial ability and attitude - with student chemistry performance, and provides psychometric evidence for using the Purdue Visualization of Rotations test (ROT) and Attitude toward the Subject of Chemistry Inventory (ASCIv2) to measure these two factors, respectively, in …

Mole Street Journal, October 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Mole Street Journal, September 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Design, Synthesis And Biological Evaluation Of Small Molecule Inhibitors Of The Hedgehog Signaling Pathway, Upasana Banerjee

Doctoral Dissertations

The Hedgehog (Hh) signaling is an important embryonic developmental pathway normally responsible for tissue growth, differentiation and patterning. However, aberrant activity of this signaling cascade has been implicated in several types of cancer. Therefore, inhibition of the dysregulated pathway is a promising therapeutic target for treating Hh-dependent malignancies such as basal cell carcinoma (BCC) and medulloblastoma (MB). Previous studies resulted in the FDA approval of Vismodegib, a small molecule inhibitor of the Hh pathway, for the treatment of advanced BCC. Similarly, several other small molecule Hh antagonists have progressed into clinical trials. Moreover, several components within the Hh pathway have …

Mole Street Journal, August 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Chmy 221.01: Organic Chemistry I, Nigel D. Priestley

University of Montana Course Syllabi

No abstract provided.

Neuroinflammation And Neurologic Deficits In Diabetes Linked To Brain Accumulation Of Amylin, Sarah Srodulski, Savita Sharma, Adam B. Bachstetter, Jennifer M. Brelsfoard, Conrado Pascual, Xinmin Simon Xie, Kathryn E. Saatman, Linda J. Van Eldik, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: We recently found that brain tissue from patients with type-2 diabetes (T2D) and cognitive impairment contains deposits of amylin, an amyloidogenic hormone synthesized and co-secreted with insulin by pancreatic β-cells. Amylin deposition is promoted by chronic hypersecretion of amylin (hyperamylinemia), which is common in humans with obesity or pre-diabetic insulin resistance. Human amylin oligomerizes quickly when oversecreted, which is toxic, induces inflammation in pancreatic islets and contributes to the development of T2D. Here, we tested the hypothesis that accumulation of oligomerized amylin affects brain function.

METHODS: In contrast to amylin from humans, rodent amylin is neither amyloidogenic nor cytotoxic. …

Mole Street Journal, July 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Electron Transfer In Pnicogen Bond, Liangyu Guan

Masters Theses

Abstract is available for download as a separate file.

Synthesis, Design, And Environmental Fate Of Metallic Nanoparticles, Ashley E. Hart

All Dissertations

Rational design of nanoparticle surface chemistry offers the ability to control nanoparticle characteristics such as size, polydispersity, shape, dispersibility in various solvents, functionality and end fate. Ligand exchange has proved to be is a versatile method for modifying the surface of plasmonic nanoparticles. Ligand exchange has provided a “green” alternative to traditional biphasic syntheses that require large amounts of phase transfer catalysts. Ligand exchange can also be used to reduce the amount of post synthesis processing and waste when it is conducted on nanoparticles that have been synthesized with a method that affords control over nanoparticle size and polydispersity. Ligand …

Mole Street Journal, June 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Neutral Networks Of Real-World Programs And Their Application To Automated Software Evolution, Eric Schulte

Computer Science ETDs

The existing software development ecosystem is the product of evolutionary forces, and consequently real-world software is amenable to improvement through automated evolutionary techniques. This dissertation presents empirical evidence that software is inherently robust to small randomized program transformations, or 'mutations. Simple and general mutation operations are demonstrated that can be applied to software source code, compiled assembler code, or directly to binary executables. These mutations often generate variants of working programs that differ significantly from the original, yet remain fully functional. Applying successive mutations to the same software program uncovers large 'neutral networks' of fully functional variants of real-world software …

Mole Street Journal, May 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Mole Street Journal, April 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Exploring Students' Perceptions And Performance On Predict-Observe-Explain Tasks In High School Chemistry Laboratory, Praveen Vadapally

Dissertations

This study sought to understand the impact of gender and reasoning level on students’ perceptions and performances of Predict-Observe-Explain (POE) laboratory tasks in a high school chemistry laboratory. Several literature reviews have reported that students at all levels have not developed the specific knowledge and skills that were expected from their laboratory work. Studies conducted over the last several decades have found that boys tend to be more successful than girls in science and mathematics courses. However, some recent studies have suggested that girls may be reducing this gender gap. This gender difference is the focal point of this research …

Design Optimization Of A Composite Wing Box For High-Altitude Long-Endurance Aircraft, Philip T. Arévalo

Doctoral Dissertations and Master's Theses

A design optimization process is developed to define the wing box structure for High-Altitude Long-Endurance Aircraft (HALE). The goal of this study is to determine the best tradeoff between mass and rigidity of a HALE aircraft wing structure. A preliminary composite laminate structural design procedure is described which uses a NASTRAN-based Finite Element Analysis (FEA), and the Hierarchical Evolutionary Engineering Design System (HEEDS) MDO software to define a locus of acceptable, optimized wing box design definitions.

The Wooster Voice (Wooster, Oh), 2014-04-25, Wooster Voice Editors

The Voice: 2012-Present

News articles in this issue of the Voice are "Students petition for new counselor" for better resources for LGBTQ+ students, "Student groups commemorate Galpin Takeover 25-year anniversary," "Student threatened by motorist with violence and racial epithets," "Dining Services to change smoothie selection next fall," and "Security presence increased at Lip Sync, results disputed." In Features, there are articles on I.S. Symposium, Luce Scholarship recipients, the Physics Club's Community Science Day, WOO91's Cornhole Tournament, and the Humans of Wooster. The Arts and Entertainment section has articles on Springfest and the Goliard Literary Magazine. In Sports, there are articles on women's lacrosse, …

Mole Street Journal, March 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Histological And Immunohistochemical Study On The Effect Of Melatonin In Rat Cerebellar Cortex Injury After Transient Bilateral Common Carotid Artery Ligation, Dalia A. Shabaan, Awny H. Yaseen, Amany S. El-Lakany, Amany A. El-Hawwary

Mansoura Medical Journal

Brain ischemia is a condition inwhich there is insufficient blood flowto meet its metabolic demands leadingto many functional and structuralchanges.The cerebellum is consideredone of the vulnerable regionsforbrain ischemia. Melatonin, producedby the pineal gland, has antioxidant,anti-inflammatory and antiapoptoticeffects. Therefore, thecurrentstudy has been performed toevaluatethe effect of melatonin administrationon induced ischemic reperfusioninjury (I/R) in rat cerebellarcortex.Thirty adult male albino ratswereused and divided into threegroups(10 rats / group). Group Acontainedthe sham-control rats, while group B included I/R rats whichwere subjected to transient ischemiaby ligation of both common carotidarteries simultaneously for 10 minutesand subdivided into 2 subgroups;B1(3 days after I/R) and B2(onemonth after I/R). …

Mole Street Journal, February 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Mole Street Journal, January 2014, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

"What Does This Graph Mean?" Formative Assessment With Science Inquiry To Improve Data Analysis, Andrea Dawn Leech

Dissertations and Theses

This study investigated the use of formative assessment to improve three specific data analysis skills within the context of a high school chemistry class: graph interpretation, pattern recognition, and making conclusions based on data. Students need to be able to collect data, analyze that data, and produce accurate scientific explanations (NRC, 2011) if they want to be ready for college and careers after high school. This mixed methods study, performed in a high school chemistry classroom, investigated the impact of the formative assessment process on data analysis skills that require higher order thinking. We hypothesized that the use of evaluative …

Electronic Properties Of Inp (001)/Hfo2 (001) Interface: Band Offsets And Oxygen Dependence, Santosh Kc

Faculty Publications

Using ab-initio methods, atomic structures and electronic properties of InP (001)/HfO2 (001) interface are studied within the framework of density functional theory. We examine the InP/HfO2 model interface electronic structures under varying oxidation conditions. The effects of indium and phosphorous concentrations on interfacial bonding, defect states, band offsets, and the thermodynamic stability at the interface are also investigated. The origin of interfacial gap states in InP (001)/HfO2 (001) interface are proposed, mainly from the P-rich oxides, which is validated by our experimental work. This highlights the importance of surface passivation prior to high-κ deposition based on the in situ spectroscopic …

Mole Street Journal, December 2013, University Of Arkansas, Fayetteville. Dept. Of Chemistry And Biochemistry

Mole Street Journal

No abstract provided.

Human Hair Keratin Protein, Hair Fibers And Hydroxyapatite (Ha) Composite Scaffold For Bone Tissue Regeneration, Samuel Siyum

ETD Archive

The field of tissue engineering aims at promoting the regeneration of tissues or replacement of failing or malfunctioning tissue by means of combining a scaffold material, adequate cells and bioactive molecules. Different materials have been proposed for use as three-dimensional porous scaffolds for bone tissue engineering procedures. Among them, polymers of natural origin are one of the most attractive options mainly due to their similarities with the extracellular matrix (ECM), chemical versatility as well as typically good biological performance. In this study, two biocompatible composite scaffolds were developed from natural polymer by tissue engineering approach and tested in vitro. The …