CHEM2018OCHOA41556 CHEM
Type: Graduate
Author(s):
Charles Ochoa
Chemistry & Biochemistry
Advisor(s):
David Minter
Chemistry & Biochemistry
(Presentation is private)Hippadine and pratosine are lycorine-type pharmacologically active Amaryllidaceae alkaloids. Various total syntheses of these natural products have been developed. However, most of these synthetic routes require prohibitively expensive materials and/or achieve yields that are subpar, making these schemes unlikely to be used in an industrial setting. Current research involves developing better synthetic methods for these two alkaloids starting with a 6,7-disubstituted isoquinoline. These syntheses are appealing since they utilize readily available starting materials and avoid expensive catalysts. The key step in the synthetic scheme centers around an intramolecular de Mayo photocyclization which involves a reaction between an alkene moiety in the isocarbostyril system and a 1,3-diketone (a functionalized tether on nitrogen), which forms a third ring in the structure of the molecule. When the photochemical reaction was attempted, an unexpected cyclic photoproduct was obtained; fortunately, this product is a cyclic hemiketal of the expected 1,5-dicarbonyl compound. A base-catalyzed aldol addition affords the final ring in the system; dehydration of this product affords a β-enone that can be transformed to a diene. Oxidation of the diene with DDQ affords the target natural products after simple chromatographic purification. This new synthetic pathway circumvents the need for catalysts that are either expensive or contain metals such as palladium or iridium; moreover, our method allows for the synthesis of various natural and unnatural alkaloids in high yields by modification of the N-tether.
CHEM2018PARKER27356 CHEM
Type: Undergraduate
Author(s):
Jack Parker
Chemistry & Biochemistry
Marianne Burnett
Chemistry & Biochemistry
Hannah Johnston
Chemistry & Biochemistry
Advisor(s):
Kayla Green
Chemistry & Biochemistry
(Presentation is private)Molecules previously developed by the Green Research Group (L2 and L3) have been shown to reduce reactive oxygen species (ROS) through multiple pathways of activity. Although unclear if ROS is the only source, Alzheimer’s disease and other neurodegenerative disorders are known to be initiated from the formation of these ROS. For these molecules to appropriately execute their antioxidant and radical scavenging ability, they must enter into the brain where the damaging ROS are located. The blood brain barrier (BBB) is a natural obstacle that prevents toxins and infections from reaching the brain. The L2 and L3 ligands must penetrate this barrier to be in the desired site of action to reduce the number of ROS. Addition of a glucose moiety to other therapeutic molecules has been shown to increase permeability across the BBB. The target of this project is to enhance these synthetic pathways of glycosylation and increase product yield. Initially, direct addition of the glucose moiety to the L2 and L3 molecules was achieved. However, challenges with purification techniques suggested a different route to purification or design should be considered and one new route is presented here. With L2 and L3 being inherently hydrophilic, addition of an aliphatic chain to the hydroxyl group of L2 or L3 should increase the hydrophobicity of the molecule allowing for different purification techniques, which can ultimately be glycosylated to give purified desired compounds.
CHEM2018RODRIGUEZ3379 CHEM
Type: Undergraduate
Author(s):
Adriana Rodriguez
Chemistry & Biochemistry
Advisor(s):
Jeff Coffer
Chemistry & Biochemistry
View PresentationA recent and promising development in solar energy involves a class of materials known as organometal halide perovskites, capable of efficiencies (>20%) comparable to the current industry standard of silicon. These materials also demonstrate strong light emission, a key property associated with energy-efficient sources of lighting, suggesting potential applications in light-emitting devices such as light-emitting diodes (LED). The goal of this project was to investigate the fundamental photoluminescence (PL) properties of perovskites housed in a nanoporous material known as semiconducting porous silicon (pSi).
pSi provides a nanoscale template to control the growth of the light-emitting perovskite structure and is an electrically-responsive host matrix, ideally regulating the flow of charge to/from the perovskite. Samples were prepared within the pores of surface oxidized pSi and hydride-terminated pSi, each with a mesoporous width in the 5 – 50 nm range. The perovskite-loaded pSi was fabricated through solution-loading of perovskite precursors into warmed pSi (60ºC), removal of excess reactant solution, and drying. While perovskites can feature a wide range of halide compositions (including mixed halides), this research thus far has focused on methylammonium lead iodide (MAPbI3) perovskite.
These perovskite nanostructures formed within pSi were characterized using a variety of techniques. Following synthesis, the stability of each prepared sample was monitored for 3 weeks through tracking its relative photoluminescence intensity at its maximum value. Perovskite morphology was evaluated by SEM (scanning electron microscope) and TEM (transmission electron microscope) imaging, crystalline structure was evaluated by XRD (x-ray powder diffraction), and elemental analysis was evaluated by EDX (energy-dispersive x-ray spectroscopy).
In this study, SEM imaging showed consistent perovskite particle size and ununiformed perovskite infiltration. It is found that the emission intensity for MAPbI3 formed within hydride-terminated pSi (at ~730nm) and oxidized pSi (at ~740nm) were relatively stable over a 3 week period, but the emission intensity for perovskite microrods formed in the absence of any pSi template actually decreased over time. More detailed measurements of the long term stability of these new nanoscale materials are currently under evaluation.
CHEM2018TRETTE12261 CHEM
Type: Undergraduate
Author(s):
Sayre Trette
Chemistry & Biochemistry
Nelli Bodiford
Chemistry & Biochemistry
Nathan Shurtleff
Chemistry & Biochemistry
Advisor(s):
Jeffery Coffer
Chemistry & Biochemistry
(Presentation is private)Significant increases in average life expectancy in the last century have brought a growth in human illnesses related to aging: chronic wounds, bone diseases, eye diseases and cancer. In this work, we demonstrate fabrication of biodegradable polymer scaffolds that can be used for drug delivery and tissue engineering to treat the above-mentioned ailments. Tissue engineering can be defined as the use of a combination of engineering and materials methods and appropriate biochemical factors to improve or replace biological tissues.
This project includes fabrication of solid and porous fibers from the biocompatible PCL polymer. This polymer is currently used for surgical sutures, nerve guides and three-dimensional scaffolds for use in tissue engineering. The drug release rate is faster when it is loaded into porous PCL fibers compared to solid PCL fibers, creating an advantage for porous fiber fabrication. Use of a technique known as electrospinning of a solution of PCL and chloroform results in solid fibers that are 4 (± 2.0) micrometers (μm) in diameter. The porous fiber scaffolds are fabricated using a 50% weight of PCL compared to volume of solvent (w/v) solution prepared in a mixture of solvents 9:1 dichloromethane (DCM):dimethyl sulfoxide (DMSO) and 60% w/v PCL in 8:2 DCM:DMSO. The porous fibers are collected at 0-5 oC with a pore size of 50.0 (± 10.0) nanmoeters (nm) and fiber diameter of 3.0 (± 1.0) μm. The porosity for 50% w/v PCL and 60% w/v PCL fibers ranges from 40-50%.
Fiber surface morphology is characterized using field emission scanning electron microscopy (FESEM). In addition, the melting temperature and percent crystallinity are determined via differential scanning calorimetry (DSC). The melting temperature was collected of PCL bulk, 30%w/w PCL solid fibers, 50% w/v PCL and 60% w/v PCL. The crystallinity of PCL in solid fiber and porous fiber forms ranges from 52-55%, compared to the 60% crystallinity of PCL bulk. Solid PCL fibers showed to be more crystalline compared to porous PCL fibers, which in turn can effect the degradation time.
In order for these composites to be identified as a major technological advancement, the aging and degradation of the polymer scaffold must also be understood. The degradation of a given polymer matrix impacts the potential drug delivery behavior when testing in vitro. Degradation studies of the above mentioned materials are currently ongoing.
CHEM2018VILLEGAS47591 CHEM
Type: Undergraduate
Author(s):
Hector Villegas
Chemistry & Biochemistry
Advisor(s):
Benjamin Janesko
Chemistry & Biochemistry
(Presentation is private)While cis/Z-substituted alkenes are usually less stable than their trans/E-substituted counterparts, the cis-2-butenyl anion shows a higher preference over the trans-isomer. Calculations suggest that the discrepancy is due to two cooperating effects: electrostatic interactions between the anionic center (C1) to the methyl group (C4) and coupling between the C=C pi* antibonding orbital and both the CH2 pz and CH3 C-H sigma bonds. Supporting the charge transfer is the fact that substitution on C1 with EDG stabilizes the cis more while substitution on C4 with EWG stabilizes the cis more. For the coupling interaction the C=C bond was stretched which increased the cis stabilization by lowering the pi* orbital energy and increasing the coupling between the lone pair on C1 and pi*.
COSC2018COX17551 COSC
Type: Undergraduate
Author(s):
Connor Cox
Computer Science
Kaitlin Hendrick
Computer Science
Kiet Nguyen
Computer Science
Jim Pfluger
Computer Science
Advisor(s):
Lisa Ball
Computer Science
View PresentationGeology is better known for work done in the field than software applications, but by combining software with science, researchers can acquire results more efficiently and make better determinations about data. Stream input data, which consists of variables like stream size, depth, and sediment density, can be used to predict the location of oil deposits. Without a software application to automate the process, this is difficult to calculate manually.
This application will provide a useful resource and tool by which researchers can input geological data and have results returned based on that input. Specifically, users will enter data about streams and select one of two primary methods of calculation which will return results that refine sediment discharge estimates and give the user the yearly averaged bankfull flow duration. To achieve this we have implemented a database to store all of the necessary information concerning the stream data, such as location, climate ID, and Koeppen classification, established software to function as middleware between the database and the user interface, and built a web application that can be readily accessed online. With no knowledge of the middleware or database, the expected user can simply go on the website, select the desired method of calculation, and have the data returned to them in an easily understandable format.
COSC2018GONZALEZ13220 COSC
Type: Undergraduate
Author(s):
Rebecca Gonzalez
Computer Science
Daniel Fletcher
Computer Science
Ford McDonald
Computer Science
Luke Reddick
Computer Science
Advisor(s):
Lisa Ball
Computer Science
View PresentationNaturally Curly Cook is a baking business that does catering, standing coffee shop orders, and Farmer’s Markets. Currently, Naturally Curly Cook is having difficulty with its current pen and paper ordering system and inefficient invoicing. The purpose of the Naturally Curly Cook Team is to create an iOS application that streamlines ordering and invoicing. The application will display a daily baking list and what the bakers must bake with a check box system to ensure everything has been baked. It will also display weekly orders. Orders can be added, edited, and deleted while still maintaining the orders that do not change week to week. Excel will act as the database for all customers, orders and quantities to be stored. In addition to the ordering process, an invoicing process will allow invoices to be automatically generated from the week’s orders. The new invoicing process will be generated from Excel and will allow for different pricing options and it will update with week to week changes. The intent of this project is to create a more automatic and efficient business while cutting costs and most importantly retaining data integrity.
COSC2018HENDRICK21849 COSC
Type: Undergraduate
Author(s):
Kaitlin Hendrick
Computer Science
Advisor(s):
Michael Scherger
Computer Science
View PresentationThis research analyzes artificial intelligence techniques for Konane. The game Konane, also known as Hawaiian checkers, is a two-player, zero-sum strategy board game ideally suited for this research. The game ends when a player does not have a move in which they can capture an opponent’s piece. In order to have a successful strategy, a player must consider many future possibilities. For this reason, this project compares computing agents that use informed and uninformed searching algorithms. We focus our investigation on the effectiveness of the minimax and minimax with alpha-beta pruning algorithms. By altering several variables, specifically the cutoff depth for searching the game tree, we begin to see varying levels of success from the competing computing agents. The outcome of this research will be an analysis of the effectiveness of each computing agent. One of our evaluation metrics will be games statistics, such as ratio of wins to losses, time to win, and how many pieces lost.
COSC2018LARSEN32693 COSC
Type: Undergraduate
Author(s):
Nicholas Larsen
Computer Science
Harrison Cao
Computer Science
Minh Hoang
Computer Science
Advisor(s):
Liran Ma
Computer Science
View PresentationDistinct Sound
In the United States alone, 48 million people suffer from hearing loss. Sadly, about only 20 percent of them who could benefit from a hearing aid can afford to wear one. However, most people have a smartphone. Therefore, Distinct Sound strives to create an iPhone application that possesses similar functionalities of a conventional hearing aid at a fraction of the price. The two main objectives of our application are to remove background noise and to amplify sound in certain frequency ranges needed for speech comprehension. To complete those tasks, our app will take input sound, process that sound and amplify the frequencies that the user cannot hear as well, then replay the processed sound to the speakers through headphones. Those tasks will involve the fast fourier transform, and some sound processing to make sure that the sound does not have gaps. The app also provides a test to check the accuracy of the prescription in the current environment. If the current environment needs to adjust the prescription to make it more comfortable for the user, then a calibration test will work to fix the prescription according to the current environment. In conclusion, the research project will be considered a success if the application can successfully serve as a hearing aid with some functions that are unique on the market. It should benefit people who cannot afford traditional hearing aids.
COSC2018REDDICK19284 COSC
Type: Undergraduate
Author(s):
Luke Reddick
Computer Science
Advisor(s):
Liran Ma
Computer Science
View PresentationThis paper covers a comprehensive implementation of a blockchain based voting platform. Blockchain, in its infancy, has shown remarkable use cases with cryptocurrencies and we would like to expand upon its possibilities. Voting is a system ripe with opportunity for blockchain; it requires security, consensus, and portability- all qualities inherited from blockchain technology. In this paper, we discuss the appeal of blockchain technology and why we want to elevate voting to 21st century technology. Next, we survey the needs of a voting platform and how blockchain might satiate those requirements. Finally, we propose a voting platform that will run on the Ethereum network and systematically discuss how this application could come to fruition.