State of North Carolina

Undergraduate Research Symposium

Engineering, Technology, and Mathematics Abstracts

Student Author(s):	Brinkley, Stuart E.
Dept & College or University:	Computer and Electrical Engineering, NCSU
Research Mentor(s):	John F. Muth/Computer and Electrical Engineering, NCSU
Title of Presentation:	Hadamard Spectroscopy for Low Cost Medical Imaging

Medical imaging in its current implementation is an expensive process if high resolution and high accuracy is desired. For the purposes of this project we sought to design and build a prototypical system in which high resolution images could be obtained without the large expenses currently associated with such systems (MRI and various other spectroscopy techniques). This has been achieved through using a special time division digital coding technique to allow for a single photodetector to be used for image construction. It is by using one photodetector that we are able to achieve low system costs. Traditionally it would take more and more photodetectors to increase the resolution of an imaging system, but we have been able to circumvent

this problem with a special coding algorithm. With an initial demonstration of the proposed device confirming basic theory at the heart of the project, now we seek to fine tune and improve the system and build a 2nd generation device to further demonstrate high resolution capabilities. The goal is to demonstrate to the medical community that a low cost option for medical imaging is possible and will be available to allow for lower cost services for their clients in the near future. The system will eventually undergo further testing to demonstrate its durability in a medical laboratory and its safety for human subjects after it has been used for imaging laboratory animals.

Student Author(s):	Chaffin, Amanda
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	Game2Learn: The CyberCafe

In order to combat the growing decline of students that complete their course of study in computer science, we formed the Game2Learn group. Our group is dedicated to teaching, through game play, the fundamentals of computer science such as basic programming. Currently, the introductory computer science classes teach the basics via lectures coupled with programming assignments that may not motivate or interest a diverse group of students who may learn differently, having grown up with advanced technologies for games, movies, and the internet.

We are designing a game where students learn to program. In this game, students discover that their favorite artist has been kidnapped while studying at the local cyber café. Using 3D GameStudio, I am building the ‘cyber café’ level of our game where players learn that their favorite artist has been kidnapped and the police are offering a substantial reward for information. The player will have at least three opportunities to learn about the kidnapping while in the café; there will be wanted posters on the walls, the player’s virtual computer will show a flagged message upon login, and another character in the café will also tell the player about the kidnapping and lead the player to watch a mini-movie (like a news clip). The movie will be made with the assistance of UNCC’s theater department, a digital camera, and Windows Movie Maker.

Student Author(s):	Clapp, Mark A. Odom, Devin
Dept & College or University:	Biomedical Engineering, NCSU Biomedical Engineering, Duke University
Research Mentor(s):	Lawrence M. Boyd/Biomedical Engineering, Duke University Liufang Jin/Biomedical Engineering, Duke University Jun Chen/Biomedical Engineering, Duke University Lori A. Setton/Biomedical Engineering, Duke University William J. Richardson/Orthopaedic Surgery, Duke University Medical Center
Title of Presentation:	Development of an In Vitro Culture System for Compressive Loading of Intervertebral Discs of the Murine Spine

Altered mechanical loading has been historically linked to the onset of intervertebral disc (IVD) degeneration. Our objective was to develop an in vitro culture system that will permit studies of the responsiveness of IVDs to altered mechanical loading, towards the goal of understanding the pathology of IVD degeneration. A test frame was designed using four symmetrically placed springs to apply well-controlled compressive loads across IVDs isolated from mouse spines while permitting free diffusion of essential nutrients. Coccygeal spines were harvested, sectioned and placed into the loading fixture and cultured in 6-well plates. For the first 24 hours a 0.1 MPa tare load was applied. After 24 hours, half of the segments received a compressive load of 1.0 MPa for an additional 24 hours. After loading, IVD tissue was separated into anulus fibrosus (AF) and nucleus pulposus (NP) regions and frozen. For each experiment (n=3), tissue was pooled (n=16 IVD) for RNA isolation and gene expression studies using real-time RT-PCR. Gene expression patterns differed between AF and NP, with a trend toward decreased anabolic and increased catabolic gene expression (values above 2-fold as noted). For AF, collagen types I and II decreased, aggrecan increased (2.28-fold), and matrix-degrading enzymes all increased (MMP-3;MMP-13;ADAMTS-4 (2.07-fold)). In NP, type I collagen increased, type II collagen decreased, while MMP-3 decreased (-3.4-fold), and ADAMTS-4 increased (2.3-fold). Understanding changes in gene expression under mechanical loading of mouse spine segments will facilitate future studies that examine interactions between mechanical loading and genetic background using knockout models of IVD degeneration.

Student Author(s):	Crouch, Michael
Dept & College or University:	Textile Engineering, NCSU
Research Mentor(s):	Juan Hinestroza/Textile Engineering, NCSU
Title of Presentation:	Investigating the Effects of Mechanical Deformation on the Permeability of Protective Clothing Using FTIR Spectroscopy

Neoprene is one of the most common materials used in protective clothing applications. Under normal usage conditions, protective clothing materials such as gloves, boots and coats are under constant mechanical deformation. However, existing testing methodologies do not account for the effect of mechanical deformation on the barrier properties of protective clothing. This project aims at understanding the effect of mechanical deformation on the permeability of neoprene using a custom made apparatus coupled to a FTIR Spectrometer equipped with a variable path length gas cell. An automation macro has been created to take repeated spectral measurements against a nitrogen background, at consistent intervals, of the amount of permeant that has penetrated the Neoprene sample. All spectral graphs are saved, and permeant concentration profiles are created for further analysis. A second automation macro has been created, for offline use, to assist in finding the IR peaks that are most characteristic of that permeant at high concentrations and to identify potential decomposition products originated by interactions between the neoprene and the challenging agent.

Student Author(s):	Desai, Amit Y. Lutkenhaus, Jodie L.
Dept & College or University:	Materials Science & Engineering, NCSU Chemical Engineering, Massachusetts Institute of Technology
Research Mentor(s):	Paula T. Hammond/Chemical Engineering, Massachusetts Institute of Technology
Title of Presentation:	Nanocomposites of PEO/Clay for Multilayer Polymer Electrolytes

Polyethylene oxide (PEO) has been a polymer electrolyte of interest because of its low glass transition temperature, its ability to coordinate with cations, and its relative electrochemical stability. However, the crystallinity of pure PEO detracts from its ability to transport ions through the electrolyte matrix. In addition roughly 30 percent of the ionic current is carried by the cation rather than the anion, and in a lithium battery, this property can cause concentration polarization. To reduce crystallite formation in PEO and promote the conduction of a single ion, we introduce a system that utilizes the power of the layer-by-layer (LBL) assembly method where a substrate is alternately exposed to aqueous solution of polymer A and then polymer B. The LBL method is particularly advantageous for electrolytes because it provides a platform to enhance the electrode-electrolyte interface, for which every crevice of an electrode is conformally coated by the LBL film. The assembly technique also produces ultrathin films of nanometer-scale controlled thickness. In this case, we investigate hydrogen bonded composites of Laponite clay and PEO. Through thermal gravimetric analysis, scanning electron microscopy, and electrochemical characterization, we present preliminary results of the composite films. Laponite, a synthetic hectorite clay, is of particular interest because the clay behaves as a single ion conductor or cation exchange medium. Combining clay and PEO with the layer-by-layer assembly technique allows the construction of ultrathin films with electrochemical functionality and tunable structure.

Student Author(s):	Dixon, Anthony D. David, John
Dept & College or University:	Mathematics, NCSU
Research Mentor(s):	Hien T. Tran/Mathematics, NCSU
Title of Presentation:	Model of Acoustic Pressure Waves in a PVC Pipe

The understanding of acoustic pressures waves and the corresponding boundary conditions can help acoustic engineers to choose the right materials in auditoriums or concert halls for optimal acoustic properties in the rooms. The main objective of this project is to study two types of boundary conditions corresponding to a hard plate and a soft foam sponge for acoustic pressure waves and their propagation in a PVC pipe. The experiment consisted of a long PVC pipe. Sensors were placed at three different locations on the pipe. At one end of the pipe was a loudspeaker and at the opposite end there was either a hard plate or a foam sponge. The speaker was then turned on at various frequencies, sending sound pressure waves through the pipe. Data was collected at the three sensors on the pipe. The data collected is used to validate mathematical models for the reflection coefficients at the boundary. The reflection coefficients describe how much of the pressure wave energy was absorbed by the boundary condition.

Student Author(s):	Dwight, Rachel
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	Game2Learn: The Steganography Quest

The Game2Learn project involves creating a multiplayer computer game to teach introductory computer science. In doing so, we hope to create a game that appeals to a diverse group of people including women and minorities. In our game, the player is an undergraduate computer science student who discovers that a kidnapped digital artist is uploading artwork to a community digital art museum. In his computer science course, he has just learned how to write a small program that scans digital art for hidden embedded messages. The police are getting nowhere on the case, so the player decides to scan the artist’s work for messages – and he does find clues in the digital art! This is the beginning of the student’s quest to uncover the mystery of this kidnapping. I am currently working on a prototype for this part of the game. Specifically, I have created the art museum (which is underwater for added interest) and written script files to allow the player to find the embedded messages once she has written and uploaded her decoding program. I am working to design a way for students to write programs in the course of game play, either through writing code within the game, or by uploading and running their already-written program file while playing the game. This will allow students to be creative while also providing concrete, visual feedback for their programs.

Student Author(s):	Finger, Allison R.
Dept & College or University:	Biomedical Engineering, NCSU and UNC-Chapel Hill
Research Mentor(s):	Elizabeth G. Loboa/Biomedical Engineering, NCSU and UNC-Chapel Hill
Title of Presentation:	Cyclic Hydrostatic Pressure Promotes Chondrogenic Differentiation of Osteoarthritic and Normal Human Mesenchymal Stem Cells

Human mesenchymal stem cells (hMSCs) may provide more complete cartilage repair than current treatments for cartilage damage due to osteoarthritis (OA), due to their ability to undergo chondrogenic differentiation with the application of appropriate chemical and/or mechanical stimuli. The purpose of this study was to determine if hMSCs from OA donors exhibit a chondrogenic response when subjected to cyclic hydrostatic pressure (CHP) in the absence of chemical stimuli, and if the response is different from that of hMSCs from normal donors. We hypothesized that hMSCs from normal and OA donors would both show a positive chondrogenic response to CHP, but to a lesser extent in OA hMSCs. Human MSCs from normal and OA donors were seeded in 2% agarose constructs. Constructs were cyclically loaded in an oil-filled 1L pressure vessel kept at 37ºC. CHP was applied for 4 hours a day at 7.5 MPa, 1Hz for up to 21 days. Control constructs remained in static culture at 37ºC during loading. Real time RT-PCR analysis was performed on samples taken at days 7, 14, and 21 to determine mRNA expression levels of aggrecan, Sox9, and types I and II collagen. No type II collagen was seen in any sample; however, both normal and OA loaded constructs showed upregulated Sox9 mRNA expression at day 7, and increased aggrecan mRNA expression by day 21. CHP produced a positive chondrogenic response in normal and OA hMSCs without chemical stimuli, but normal hMSCs responded more quickly with respect to aggrecan mRNA expression.

Student Author(s):	Gould, Troy D.
Dept & College or University:	Chemical Engineering; Textile Engineering, NCSU
Research Mentor(s):	Juan Hinestroza/Textile Engineering, Chemistry and Science, NCSU Gerardo Montero/Textile Engineering, Chemistry and Science, NCSU
Title of Presentation:	Electrospun Polyethylene Oxide Nanofibers with Self-Assembled Magnetic Nanoparticles

Electrospinning of polymeric solutions has gained much interest due to the ability of this process to consistently fabricate nanoscale fibers (<100 nanometers in diameter.) In this research, Polyethylene oxide (PEO) magnetic nanofibers were electrospun for possible use in anti-counterfeiting applications. The goal of this research is to optimize the electrospinning of PEO magnetic nanofibers, and characterize the fibers and nanoparticle dispersion therein. To optimize the electrospinning process, operating diagrams distinguishing regions of electrostatic stability were constructed from experimental data for three different solutions: PEO/water, PEO and NaBr/water, and a PEO/water solution with suspended magnetite nanoparticles. Comparison of different electric fields and flow rates yielded optimal parameters to electrospin PEO nanofibers. Analysis of the nanofibers via Transmission and Scanning Electron Microscopy provided information on fiber morphology as well as nanoparticle distribution within the fiber. Future work aims to further characterize the nanofibers via energy dispersive spectroscopy x-ray microanalysis (EDS), as well as study and manipulate the magnetic properties of the fibers.

Student Author(s):	Gullett, Gregory L.
Dept & College or University:	Math-Computer Science, UNC-Pembroke
Research Mentor(s):	Deok-Hyung Hwang/Math-Computer Science, UNC-Pembroke
Title of Presentation:	Creation of a Web Application Using PHP and a Relational Database Management System

This research project will be based on the development of a database driven web application using PHP and MySQL. The program will have 5 essential tiers. These tiers are: the web interface, web server, the language module, and the relational database software. The Programs to develop this application will be: Apache 2.0.54, PHP 4.4.0, MySQL RDBMS 5.0. The application will be coded through an IDE called Crimson Editor v3.70 and will be tested and produced to be run via Microsoft Internet Explorer 6.0. The platform for this project is a AMD Athlon XP 2700+ processor, 1gig RAM, 300gb Hard drive space, with all Apache, PHP, and MySQL running as services. The application will use this structure: Five relational tables. News, content, tutorials, and mailing list are the tables that will be used outright and as joins to serve content for a website. PHP and HTML will be used to code the user interface portion of this project. The Hyper-text Processor language, better known by its recursive acronym as PHP will be used as an interface between the user and the MySQL database. PHP allows you to imbed MySQL commands and use the functions/processes/variables from PHP to run commands that produce the content that is displayed on the project website. The project in the future will be involved in increasing the dynamic ability of the website by using JAVA scripting, JSP etc.

Student Author(s):	Hare, Brian C. Gracien, Katina F.
Dept & College or University:	Statistics, NCSU
Research Mentor(s):	William F. Hunt/Statistics, NCSU
Title of Presentation:	Creating an Emission Standard

We need emission standards to keep industries from producing excessive amounts of harmful chemicals. These standards are enforced by a regulating company that monitors the chemicals emitted from pollution sources. To help monitor these pollution levels, there is usually a limit or emission standard that cannot be exceeded. This research project dealt with a particular industry that was monitored for a month giving hourly observations of Nitrogen Oxide concentrations from a stack. These hourly observations can be changed into many different useful variables. There are two types of averages that were used. The first being rolling averages that use three, eight, and twenty-four hour periods to come up with an average every hour. Second are block averages that happen in three, eight, and twenty-four hour blocks. These different variables were examined. Different distributions were constructed to characterize each indicator. The goodness of fit of each of these known distributions can be tested with the help of statistical software. These fitted distributions should characterize the whole population of concentrations instead of just our sample. From this, we can obtain the standard from the higher percentiles of the fitted distribution, such as the 95th or 99th percentiles. These provide us with a limit that we know should not be exceeded more than a certain percentage of the time. Using this limit, the monitoring agency has a method of deciding when an industry is exceeding the acceptable amount of pollution.

Student Author(s):	Harris, Adam
Dept & College or University:	Electrical and Computer Engineering, UNC-Charlotte
Research Mentor(s):	James M. Conrad/Electrical and Computer Engineering, UNC-Charlotte
Title of Presentation:	A Biology, Electronics, Aesthetics, Mechanics Robotics Platform

BEAM technology is a simple way of making adaptive, autonomous robots. These robots have been used for years as a learning platform for many young people interested in electronics; however, there has not been much use for them in industry. Although these small, autonomous BEAM robots could be used for many purposes, previous robots had been made to only take care of themselves, as opposed to being able to do any efficient work. The purpose for this project was to allow direct human control of a walking BEAM robot. The use of BEAM robotics for purposes beyond self preservation will provide robots that could be used for exploration among other things. Several problems were implemented in this project, such as forward turning and interfacing to other circuits. A radio frequency receiver was attached to a two motor walking BEAM robot to show that it could influence the robot to walk anywhere the person with the transmitter wanted it to go. A programmable circuit could also be attached to increase behavior and efficiency. A wide range of sensors could be interfaced to a programmable circuit that could be used for detection of explosives, water, or life signs. The entire project could also be easily scaled for larger, more capable robots.

Student Author(s):	Holland, Emily L.
Dept & College or University:	Statistics, NCSU
Research Mentor(s):	William F. Hunt/Statistics, NCSU
Title of Presentation:	Examining Year to Year Changes in the Toxic Release Inventory

The Toxic Release Inventory contains information about the releases of certain chemicals and wastes at many sources such as manufacturing industries, service businesses, and federal facilities. Businesses over a certain size are required to report their release information to the EPA annually. The USEPA posts Toxic Release Inventory data from 1988-2003 on the Internet for public access. The release level as a whole appears to be decreasing, but with new chemicals being removed and added throughout the years, it is difficult to discern if the release levels have made a significant decrease or if it is just a natural trend. By stratifying the data by industry type, chemical type, and location, significant decreases, or lack thereof, can be found. The release of toxic chemicals into the air, water, and land has been an ongoing problem in the United States. The release of these toxins into the environment hinders the health and quality of life of the people in the US. Typical yearly changes can be looked at as well, and it could be determined whether these decreases occur at similar rates or if there are significant differences in rates of change. Developing an approach to identify potential outliers (due to transcription errors, etc.) in yearly changes would also be beneficial. Also, trends in the data can be looked at on a county, state, and national level. By finding the significant decreases, people will be better informed about which areas and chemicals are showing improvements and which are showing continuing problems.

Student Author(s):	Hon, Emily W.
Dept & College or University:	Chemical Engineering, NCSU
Research Mentor(s):	Brian G. Prevo/Chemical Engineering, NCSU Orlin D. Velev/Chemical Engineering, NCSU
Title of Presentation:	Deposition and Characterization of Anti-reflective Nanoparticle Coatins on Solar Cells

Solar cells are photovoltaic devices which convert incident electromagnetic energy (or photons) into electrical energy by way of the photoelectric effect. Most solar cells are made from doped silicon based materials, which are often highly reflective. To increase the power output of most solar cells, anti-reflective (AR) coatings are applied by manufacturers to reduce the amount of energy lost by reflectance. As an alternative to energy intensive “top-down” vacuum deposition techniques, we use a “bottom up” coating approach for simple and reproducible deposition of nanoparticle coatings with controllable thickness and structure by convective assembly from aqueous silica suspensions. This technique offers an excellent means for making AR coatings from silica nanoparticles for both glass and silicon based substrates. In this investigation, three types of solar cells were studied: (i) uncoated solar cells, (ii) solar cells with existing factory deposited AR coatings, and (iii) solar cells with an existing factory deposited AR coating and a plastic protective covering. The goal was to develop a qualitative correlation between the optical and electronic properties of the solar cells. In all cases, the addition of the silica coatings was most effective in reducing device reflectance in the UV/visible range of the spectrum, with the most reduction occurring for case (i). However, after silica deposition, only minor increases in the electrical power output were observed, which could be attributed to the fact that the quantum efficiency of silicon based photovoltaic devices is highest in the near-IR range.

Student Author(s):	Hornsby, Fawn Jackson, Wilma
Dept & College or University:	Statistics, NCSU
Research Mentor(s):	William Hunt/Statistics, NCSU
Title of Presentation:	An Analysis of Continuous Mercury Air Pollution Data Collected in Elizabeth and New Brunswick, NJ

Mercury is a known toxin that bio-accumulates in the environment. Most exposure occurs from eating contaminated fish – not direct inhalation. Mercury exists in the atmosphere in both gaseous and particulate forms. Mercury can be emitted into the air and deposited in the water through atmospheric deposition. This research focuses on hourly mercury data collected at two air monitoring sites in New Jersey over a period of two years. The NJ Department of Environmental Protection took measurements of mercury in three forms: gaseous elemental mercury, particle bound mercury and reactive gas mercury. A statistical analysis evaluating seasonal, weekly, and diurnal patterns will be presented. We will discuss our approach developed to evaluate diurnal patterns for a messy and complicated data set. This will be extended to investigate wind direction and wind speed to find possible locations of the sources of mercury, such as iron and steel plants, coal fired power plants, broken products (e.g. thermometers, etc.), dental waste and municipal waste incinerators. Moreover, recent governmental laws could have affected the more recent samples and could also affect future mercury measurements taken as well. Of particular interest, on March 15, 2005 EPA passed the Clean Air Mercury Rule. Our research will use comparisons to ascertain whether these laws have had an effect in reducing mercury levels. As future measurements are taken, our analysis will serve as a starting point in verifying any changes occurring.

Student Author(s):	Huda, Sabil Gupta, Shalini
Dept & College or University:	Chemical Engineering, NCSU
Research Mentor(s):	Orlin D. Velev/Chemical Engineering, NCSU
Title of Presentation:	Development and Optimization of Gold Nanoparticle-Based Silver Enhanced Sandwich Immunoassays

Silver enhanced immunoassays provide a simple, low-cost and effective way of detecting antigens in dilute solutions, and could be directly interfaced to on-chip electrodes for electrical readout of the result. A bioassay was developed and characterized for low concentrations of antigens and antibodies using a gold nanoparticle tagging and silver-enhancement technique. Goat-anti-mouse immunoglobulin (GAM IgG) was immobilized on glass substrates, and incubated consecutively with mouse (M) IgG and gold-conjugated-GAM (GAMg) IgG to form a selective GAM-M-GAMg sandwich assembly. Silver ionic solution was then added to make the gold colloids (GAMg) visbile. The silver solution selectively deposited a layer of metal on the bound nanoparticles by reduction. The opacity of the positive spots was measured quantitatively by densitometry. With this method, 100 ng/mL (4 ng total) of mouse IgG analyte was detected in less than 10 mins. Negative and positive control experiments indicate that only sandwich assays possess high selectivity, while false positives may occur in direct assays. The results of an investigation into mass-transfer phenomenon was used to develop a model which guided the optimization of the bioassay. The results could allow the development of more rapid and reliable immunoassays.

Student Author(s):	Ingles, Brian
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	The Future of Java Game Development

In the past, the possibility of using Java for serious game development wasn’t feasible. Although Java offered some features that might have been appealing to small scale game design, it lacked the capabilities to really be considered as a tool in the gaming industry at large. This is not true today. Many arguments against using Java for gaming today are based on outdated information or a lack of understanding of Java’s functionality. Java’s speed, memory management problems, and lack of low-level operations are a few reasons commonly believed to rule out Java for game development. New technologies and better understanding of how to implement Java are diminishing these arguments more and more. Java is emerging as a strong candidate for serious game design in the future.

The focus of my research project is to learn more about Java’s suitability for future gaming and to implement a simple game in Java. My game is a tile-based action/adventure style game called Space Ninjas. My goal is to implement all of the basic functionality including walking, fighting, and interacting with other game characters. I am creating a map editor which can create, load, and save game maps to be used in the game. I have already created some of the basic game objects, so much of my future work will be to put the pieces together and add the framework that is necessary to manage them. As any extra time permits, I plan to add extra functionality to make the game more enjoyable.

Student Author(s):	Izquierdo, Christina Taylor, Anne Spottswood Vainright, Jordan Wyant, Sarah Hall, Stacey Horohoe, Katherine Pressley, Megan Glendinning, Annie Bishop, Rebekah Wilson, Sarah
Dept & College or University:	Interior Design and Merchandising, East Carolina University
Research Mentor(s):	Walter Huntley McKinnon/Interior Design and Merchandising, East Carolina University
Title of Presentation:	Unplugged and Green: Redesign of VOA Site C

The Voice of America ( V.O.A. ) Site “C” facility located near East Carolina University in Greenville, NC was a listening post and was active in intelligence gathering up to the Persian Gulf War. Since it was decommissioned and deeded to the University, it has been underutilized. A major challenge for the University in making use of the facility has been determining the best use of the space and the land that surrounds it. This project addresses this challenge by proposing several options for redesign focused on keeping the building “unplugged” and creating a home for The Center for Excellence research group and a showcase for their special project related to reducing the use of fossil fuels and utilizing “green design.”

Redesign efforts will focus on maximizing the use of Solar Daylighting without creating additional cooling or heating load and with as few electric lights as possible. It is anticipated that energy efficiency will be noticeably improved in the redesigned areas compared to the remainder of the spaces in the building. Design efforts incorporated the existing central courtyard to even out the interior illumination, skylights and other structural design solutions as well as interior functional design solutions.

Student Author(s):	Johnson, R. Curtis
Dept & College or University:	School of Engineering and Technology, Western Carolina University
Research Mentor(s):	Mark A. Azadpour/School of Engineering and Technology, Western Carolina University
Title of Presentation:	Investigation of High Voltage Generation

High voltage generation is an often-overlooked field in the realm of electrical engineering, however the problem of generating high voltages (over 1,000 volts) often occurs in many fields such as communication, power distribution, and heavy industry. Thus, if better ways of generating such high voltages are introduced an investigated, more efficient and safer devices can be built.

This investigation focuses on exploring various existing methods of generating high voltages. The methods and apparatus used include an inductive kickback circuit, a self-resonant flyback transformer, and a capacitive discharge cascade, also known as a Marx generator. The inductive kickback circuit relies on the fact that if an inductor is switched off suddenly, it will generate a voltage spike, which is directly proportional to its inductance value and the rate in current change with respect to time.

The self-resonant flyback transformer relies on using resonant voltage spikes that constructively interfere with one-another to generate even higher voltages. More than one driving option will be explored. The Marx generator works on the principle of charging a string of capacitors in parallel and then discharging in series, and the ideal output would be a brief pulse at each stage’s voltage times the number of stages.

This investigation focuses on efficiency, output, safety, practicality, reliability and power output. Thus, the ideal design would be highly efficient, have very high voltage output, be safe for the operator and surrounding equipment, be fairly easy and straightforward to implement and output enough power to be useful. This investigation explores all the above methods and analyzes their potential for creation of high voltages. Several experimental runs are devised to validate the concept.

Student Author(s):	Jones Jr., Marvin Q.
Dept & College or University:	Mathematics, Physics/NC Agricultural and Technical State University
Research Mentor(s):	Janis M. Oldham/Mathematics, NC Agricultural and Technical State University
Title of Presentation:	Speaking of Relativity III: Applications of Fractal Geometry Incorporated into Universal Expansions with Mathematical Analysis of Existence and Applications

The analysis of the fractal geometric properties of the universe can be seen through various comparisons. Using Hubbles Constant, the rate at which the universe is expanding can be deduced. However the universe seems to display fractal like behavior in terms of expansion. This project analyzes these fractal behaviors and runs a comparison on the following models: A bouncing ball, a tree, Pangaea, plant life, taxonomy, microbiology, and political affairs(economics, government makeup and distribution of power). The analysis of these comparisons will provide an answer to the fractal expansion properties of the universe. If the universe is expanding like a fractal, then can the Hubble Constant be used to create a integral curve and family of equations? The analysis of this hypothesis will create a new breakthrough in the analysis of the expansion properties of the universe. The universe does indicate that it is expanding in fractal behavior due to the analysis of the comparisons and the data from each test. Since the universe displays fractal like qualities a new theory is derived by the experimenter: Everything in the universe must have fractal like behavior. The experimenter found this to be true when analyzing the structure and complexities of the human being. Through this analysis new research and new theory is developed in showing the expansion properties of the universe.

In the previous years of investigation the analysis of a possible fractal behaving universe came into existence. In the first year, research on the Hubble constant was done in order to determine the rate at which the universe was expanding. In the second year of investigation, fractal geometry became a thought. This year was divided into two phases. The first phase the research and development of fractal theory based on continental drift theory and Pangaea. The second phase developed dealt with the applications of fractals, theoretically, to areas such as taxonomy, military and government, microbiology, continental drift, and others. The experimenter developed in this year several original equations on fractal geometry and the correlation it has with universal expansion.

In this third year of investigation the experimenter has applied the research and has begun to prove the theory that the universe is expanding like a fractal. In the third year of investigation the experimenter theorized a dynamical system is the best way to characterize the universe and how it expands. The experimenter also further investigated the research conducted in the previous years with applications to more areas.

Student Author(s):	Krenicky, Joseph N.
Dept & College or University:	Mathematical Sciences, UNC-Greensboro
Research Mentor(s):	Jan Rychtar/Mathematical Sciences, UNC-Greensboro
Title of Presentation:	No Way Out: The Prisoner's Dilemma

Evolutionary dynamics has many applications in biology, economics, and psychology. A basic knowledge of symmetric normal form games lends itself to a greater understanding of dynamic evolutionary theory. Originally developed in earlier biological research, symmetric normal form games try to explain the interactions within a population. When two strategies are available to the population, three classes result: the Prisoner's Dilemma, Coordination, and the Hawk-Dove.

Student Author(s):	Lee, Michael K.
Dept & College or University:	Computer Science, NCSU
Research Mentor(s):	Michael R. Young/Computer Science, NCSU
Title of Presentation:	Systematic Differences in Controller Inputs and Their Effects on Videogame Design

Videogames are largely defined by the interactions a game provides to a player. All interactions must occur through an input device, the videogame controller. In the past three decades of videogames, controller design has rapidly evolved with each new generation of hardware. The research conducted was to investigate the effects of changes in player input on game designs. Instead of relying on genres through context, a control-oriented genre system was devised to examine the differences in allowed interactions between games. The research also examined at the evolution of controller inputs throughout game platform history. While the effects of new controller designs and new technology were difficult to separate, input devices play a significant role in final game designs.

Student Author(s):	Massey, J. Jordan
Dept & College or University:	Biomedical Engineering, NCSU
Research Mentor(s):	Juan Hinestroza/Textile Engineering, Chemistry and Science, NCSU
Title of Presentation:	Electrostatic Self-assembly of Nanolayers of Poly(sodium 4-styrene sulfonate) and Polyethyleneimine on Cationic Cotton

In order to alter the chemical surface properties of cotton without altering its physical and comfort properties, a method of electrostatic self-assembly has been employed to deposit nanolayers on cotton. Poly(sodium 4-styrene sulfonate) (PSS) and Polyethyleneimine (PEI) solutions have been prepared as 0.15M aqueous solutions with 1 wt% sodium chloride. Polyethyleneimine was chosen as a polyelectrolyte due to its role in increasing the permeability of gram-negative bacteria. Poly(sodium 4-styrene sulfonate) is a common anionic polyelectrolyte that is used in this assembly process.

Cationization of the cotton was achieved by treatment with 2,3,epoxy trimethyl ammonium chloride. Confirmation of this cationization was made using acid dyes. The deposition of the polyelectrolyte layers occurred through sequentially dipping each substrate into alternating polyanionic and polycationic solutions with a rinse cycle in between. Successful layering has been determined through the use of X-ray photoelectron spectroscopy and Fourier Transform Infared Spectroscopy.

Potential applications for cotton with these deposited nanolayers include hospital linens and wound dressing bandages.

Student Author(s):	McIntyre, Meghan A.
Dept & College or University:	Mathematics, NCSU
Research Mentor(s):	Michael Shearer/Mathematics, NCSU
Title of Presentation:	A Lens-Shaped Particle Size Segregation Zone in Granular Avalanches

Particle size segregation is an important aspect of granular avalanches in rock slides, and on a smaller scale, in pharmaceutical processing of powers and small grains. It is often characterized by the Brazil nut effect in which large particles slide over smaller ones due to shearing, and create holes for the small ones to fall through. This whole process is known as kinetic sieving. In this presentation, simulations are shown from a nonlinear partial differential equation run in MATLAB where the unknown is the volume fraction of small particles. The solution is a lens-shaped region where small and large particles are being segregated. These results are compared with an explicit solution, also run in MATLAB, which tracks shock waves and segregation patterns in the solution. The study shows that the numerical method based on the PDE and the explicit method are identical, thus, confirming the validity of the results. This lens-shaped region is very important in understanding the dynamics of avalanches since it is thought to be a key mechanism in numerous features of avalanche flow.

Student Author(s):	MacMartin, Dan
Dept & College or University:	Mathematical Sciences, UNC-Greensboro
Research Mentor(s):	Jan Rychtar/Mathematical Sciences, UNC-Greensboro
Title of Presentation:	Bacterial Wars! A Matlab Simulation

In Ecology, evidence of biodiversity exists with colicinogenic bacteria and those bacteria who are sensitive to colicin. Sensitive bacteria can mutate to gain defense mechanisms, and then displace the colicinogenic bacteria. The end result is a real-life occurrence of Rock-Paper-Scissors game - Colicinogenic bacteria win over sensitive ones, sensitive ones win over resistant ones, and resistant ones wins over colinogenic ones. We use Matlab to model the situation by modifying and adapting previous studies, making the simulation more realistic by incorporating diffusion. Observations of the new model show this one-chases-the-other phenomenon, and if the model is carefully constructed, a clock-wise spinning is observed. In all models, coexistance of all three bacteria is observed, but eventually one will dominate the environment.

Student Author(s):	Markham, David
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	Game2Learn: Controlling Non-Player Characters and Robots

The Games2Learn project aims to help alleviate the pain many students normally face in introduction Computer Science courses because of their abstract and unforgiving nature. In Game2Learn, students will play a multiplayer online game to learn programming, for a more concrete, hands-on approach to learning Computer Science.

I am creating a basic design document for the game, as well as coding NPC (Non-Player Character) interaction, and robot AI. For the design document I will be outlining the overall premise, economy, general, game-play, and other motivations for the player in the Games2learn game. The overall focus of the design document is to give us an overall feel for the direction that the game will head in the future, and ensure that the game will have a fun atmosphere throughout that players will love to be in.

NPC dialog will be created so that text will be displayed to the screen, along with appropriate choices for the player. I will also test outputting text with a text-to-speech engine and see if that is a viable option for at least some of the NPCs in the game. In addition I will need to setup a way for NPCs to output sound files along with the text.

I will test various Robot AI techniques including pathfinding, hacking, trap avoidance, etc. The robot AI will need to be created in such a way that it is modular and different parts of the AI can be rewritten.

Student Author(s):	Morrow, Joseph M.
Dept & College or University:	Mechanical and Aerospace Engineering, NCSU
Research Mentor(s):	Stearns B. Heinzen/Mechanical and Aerospace Engineering, NCSU David Roberts/Mechanical and Aerospace Engineering, NCSU
Title of Presentation:	Aeroelastic Tailoring of a Forward-Swept Wing and Pressure Port Analysis

Modern aircraft are often designed with swept wings to improve high subsonic and supersonic performance. Though aft-swept wings are the most common wing type, it has been recognized that forward-swept wings yield many of the same benefits with the added advantage of increased aerodynamic efficiency. The main drawback to these wings has been the potential for aerodynamic and structural instabilities at high angles. This is most commonly manifested in the high loading at the wing tips, potentially causing flutter and structural failure. Recently, the use of select composite materials has made it feasible to consider forward-sweep as a viable option if sufficient aeroelastic tailoring is used in the design process to overcome the wing tip divergence. The purpose of this work is to aeroelastically tailor a forward-swept wing with a wing-loading ratio that exceeds 50:1. Wind tunnel testing will be used to verify the aerodynamic computations of CMARC, an inviscid irrotational panel code, which outputs the pressure distribution used in the ANSYS structural finite element model. Initial work will include the structural analysis of the forward-swept wing, verification of the CMARC pressure distribution, and a calibration to obtain the lift coefficient slope across the span of the wing using sets of two pressure ports located on the same vertical plane. This research will facilitate more extensive future research by verifying the ANSYS and CMARC analysis through physical loading in the NCSU wind tunnel. Future work could include more detailed wind tunnel testing and refining of the tailored structural design.

Student Author(s):	Novak, Steven
Dept & College or University:	Electrical and Computer Engineering, NCSU
Research Mentor(s):	Veena Misra/Electrical and Computer Engineering, NCSU
Title of Presentation:	An Evaluation of Ru-Pt Alloys as Metal Gate Electrodes for P-channel Metal Oxide Semiconductor Devices

Ruthenium and platinum (Ru-Pt) alloys were evaluated as a replacement for poly-silicon gate electrodes on high-? dielectrics. Both material and electrical characteristics were explored for varying material compositions and process temperature. Negligible work function tuning was realized by varying alloy composition and was only evident at high temperature. Work function of 5.0±0.1eV were obtained after anneals at 400°C. Subsequent annealing caused a reduction in work functions approaching mid-gap values. X-ray diffraction (XRD) measurements indicated presence of Ru-Pt phase in samples with <80% Ru. XRD also indicated the dominance of Ru phase at higher concentrations. Auger Electron Spectroscopy (AES) confirmed the compositions of the alloys.

Student Author(s):	Patel, Sanket N.
Dept & College or University:	Biomedical Engineering, NCSU
Research Mentor(s):	Leaf Huang/Molecular Pharmaceutics, UNC-Chapel Hill
Title of Presentation:	Studying Wound Healing in Diabetic Mice Model Using Muscle Derived Stem Cells and Macrophages

Wound healing is an extremely difficult process in diabetic patients. Prolonged inflammation and poor neovascularization are common signs in such cases. Cells such as macrophages secrete so-called grow factors and have a lasting influence in the proliferation and differentiation phases of wound healing. Muscle derived stem cells (MDSCs) exhibit a strong capacity for self-renewal, multipotent differentiation, and immune privileged behavior. They can significantly improve cell-mediated therapies. The tri-block copolymer, PEG-PLGA-PEG flows freely at room temperature, but forms an adhesive hydrogel film at the wound site.

Our laboratory has studied that the thermosensitive biodegradable hydrogel provides a novel approach to wound healing. Urinary bladder membrane (UBM) is a wound matrix that has been shown to have promising effects in treating full-thickness wounds. In this study, we were able to heal wounds through topical application of macrophages and MDSCs with different biomaterials. The combination of MDSCs and hydrogel resulted in fastest wound closure among the different treatments employed. Other treatments led to wound closure as well, but not with the same acceleration.

Diabetes mellitus is one of the major contributors to chronic wound healing problems. Patients suffer from major complications including infection and amputation due to prolonged imflammation, impaired neovascularization and defective collagen formation. Continued research in this field can help treat problematic wound healing via cell therapy.

Student Author(s):	Paver, Casey
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	Game2Learn: The Steganography Quest

The aim of the Game2Learn project is to recruit and retain more students in computer science, and especially women, through creating a more fun, immersive, and interactive environment for learning. In combination with classroom lectures, students will learn the fundamentals of computer science by playing a multiplayer game created in 3DGamestudio. In the game, students will go on quests, and in the course of these quests, will create new objects and behaviors in the game through writing their own simple programs. Game2Learn’s intent is to allow both students and instructors to create new objects, missions, characters, and eventually full computer science courses in the game.

Since massively multiplayer online games (MMOGs) allow for interaction, creativity, and self-expression, and attract a diverse audience of players, we have chosen this platform as a new way of learning computer science. One important element of MMOGs is the ability to personalize your own avatar (the character that represents you in the game world). I am responsible for creating the Game2Learn avatars and all the choices for personalizing them, including at least 128 choices for different hair colors and styles, skin colors, clothing, and gender.I am also creating a mini-game where students will learn about the basic components and connections in a computer, and assemble their own virtual computer. In developing this mini-game, I will create an intuitive interface for selecting and assembling computer parts, and demonstrate mistakes with visual effects that would exaggerate what might happen in the real world.

Student Author(s):	Powell, Eve
Dept & College or University:	Computer Science, UNC-Charlotte
Research Mentor(s):	Tiffany Barnes/Computer Science, UNC-Charlotte
Title of Presentation:	Game2Learn: The Rescue

The Games2Learn project is an attempt to diversify the population in the Computer Science. Within our virtual environment, growth is not limited to the developer’s imagination and instead based on the imagination and growth of the individual. As the player grows and becomes more proficient with computer programming and scripting, they can create bigger and more useful things that they can use in the game.

Currently, we are working on one of many plots that the player will have to choose from. The student decides to investigate a kidnapping of a wealthy graphic designer in order to receive a cash prize.

I am working on a specific part of the game in which you actually gain access to the home of the graphic designer and gather clues pertaining to his whereabouts. This particular part of the game the player will be interacting heavily with the mansion, more specifically, it’s security system. The player’s goal is to gather clues without being caught by the house. In this mansion, the player comes in with their own personal PDA and Fighter-bot. The PDA interacts with the bot, allowing the player to tell the bot how to get into those ‘hard to reach’ areas of the mansion. Through a series of puzzles and other such trials, the player comes closer to finding the whereabouts of the graphic designer and slightly more knowledgeable with programming skills like, pseudocoding, path finding, and AI.

Student Author(s):	Reband, Kristen L.
Dept & College or University:	Electrical and Computer Engineering, UNC-Charlotte
Research Mentor(s):	James M. Conrad/Electrical and Computer Engineering, UNC-Charlotte
Title of Presentation:	Proving the Beam Bending Theory for Stiquito Robot Legs

In an effort to create a Stiquito robot that is half the size of the original Stiquito robot many different things have to be researched. Among them is the question of what length and diameter of spring wire should be used to work as the new legs of the Stiquito. One piece of the information needed for this is how much force is needed to move different lengths and diameters of spring wire 1mm. Certain lengths and diameters of spring wire cannot be used because they are too short and thick to be bent by the Flexinol wire. This gives the robot muscle-like propulsion. The purpose of this project was to find the force needed to move different sizes of spring wire 1mm. We examined the beam bending theory and recorded empirical measurements. This project also looked into what happens to the different sizes of spring wire as they are being bent.

Student Author(s):	Rebovich, Mary E.
Dept & College or University:	Materials Science & Engineering, NCSU
Research Mentor(s):	Juan P. Hinestroza/Textile Engineering, NCSU
Title of Presentation:	Deposition of Self –Assembled Nanolayers on Natural Fibers: Wool

Self assembled layers of polyelectrolytes (Poly(Styrene Sulfonate) and Poly(allylamide hydrochloride) were successfully deposited over wool fabrics. Anionic wool was prepared by using 2,3 epoxy tri-methyl ammonium chloride in an alkaline environment. The layers were deposited by immersing the fabric into aqueous solutions of PSS and PAH. Confirmation of the layered structure was achieved by following the evolution of the Sulfur/Nitrogen ratio on the outer layer via X-Ray Photoelectron Spectroscopy. Potential applications of this technology include the development of smart clothing and protective garments against chemical and biological agents.

Student Author(s):	Rogers, Charles R. Abiva, Jeannine T. Joseph, Edna S. Mikaelian, Arpy K.
Dept & College or University:	Mathematics, NCSU Mathematics, Loyola Marymount University Mathematics, University of the Virgin Islands, St. Thomas Mathematics, University of California, Santa Barbara
Research Mentor(s):	Erika T. Camacho/Mathematics, Loyola Marymount University Stephen A. Wirkus/Mathematics, Applied Mathematical Sciences Summer Institute (AMSSI), California State Polytechnic University, Pomona
Title of Presentation:	The Effect of Alcohol on Neuron Firing

Neurons are responsible for transmitting messages throughout the body via long distance electrical signals known as action potentials. These depend on the active transport of sodium and potassium ions across the cell membrane. The effect of various drugs on the process of neuron firing is a current research interest. The Hodgkin-Huxley equations, a system of four nonlinear ordinary differential equations, mathematically model the influx and efflux of these ions across the cell membrane. In the presence of alcohol, the release of potassium ions is accelerated. We propose a modified version of these equations, which incorporates the effect of alcohol, and examine its implications through mathematical analysis in dynamical systems. We investigate the qualitative behavior and interpret the results of the steady-state solutions in the fast and fast-slow phase planes.

Student Author(s):	Simpson, Jim A. Myers, Frankie B. Thomas, Chris M.
Dept & College or University:	Electrical and Computer Engineering, NCSU
Research Mentor(s):	Maysam Ghovanloo/Electrical and Computer Engineering, NCSU
Title of Presentation:	A High Speed USB Digital Pattern Generator and User Interface to Operate a Wireless Implantable Neural Microstimulating System

Advancements in Neuroprosthetics are leading the way forwards in the restoration of lost sensory modalities and motor disabilities. The latest developments in the real-time interfacing between external devices and implanted neuroprosthetic microstimulators call for wideband, portable, highly flexible, and universal communication medium between the external and implanted units. Interstim-2B is an existing highly versatile wireless microstimulator, which is powered and serially controlled by a frequency modulated sinusoidal carrier signal through a magnetically coupled inductive link between an external transmitter coil and an implanted receiver coil. For auditory or visual prostheses the external unit includes a microphone or video camera, respectively, from which data should be extracted, processed, modulated, and supplied to the transmitter coil.

Our research is focused on the development of a USB microcontroller system and a Windows user interface (UI) that allow generation of high speed digital patterns as a serial data bit stream. The microcontroller chosen, Cypress CY7C68013 EZ-USB FX2, supports high speed USB2 data transfer rates of up to 480 Mbit/s. A script file describing the commands to be sent is read, buffered into an output queue and sent using the USB asynchronous bulk mode. We were able to generate prolonged continuous digital patterns at 6 Mbps while rebuffering incoming new information. With pre-buffered data, however, we could achieve 24 Mbit/s continuous burst transmissions. This data rate would make it possible to generate stimulation pulses in excess of 100,000 per second, which is necessary for restoration of a functional vision or a high quality sound.

Student Author(s):	Scerbo, Siroberto Lee, Erica
Dept & College or University:	Biomedical Engineering, UNC-Chapel Hill
Research Mentor(s):	Richard L Goldberg/Biomedical Engineering, UNC-Chapel Hill
Title of Presentation:	PACMAN

PACMAN” (Pvc Assisting Child-development MANager) is a device we developed that helps babies and toddlers to build upper body strength. The device is placed adjacent to a child, who is lying on his or her stomach. When the child raises their head and shoulders, it triggers the device to provide a stimulus, such as music, bright lights, or vibration. This encourages the child to keep lifting their head and shoulders.

The device looks like a walker with wheels, with the infrared transmitter/detector unit mounted on the left, speakers mounted on the crossbeam and an mp3 player with its controller on the right side. The infrared unit is positioned to shine a beam across the device, just above the client, who is lying face down in the middle of the device. When the client pushes up, he or she breaks the infrared beam, which triggers either a switch-activated toy or the mp3 player. The infrared unit is mounted to a vertical shaft and secured by a quick release collar. As a result, the teacher can easily raise or lower the unit, so that it's located at the proper height.

The stimulus provided by the device can include music or recorded sounds to motivate the child. This is accomplished with a programmable mp3 player that uses an SD flash memory card to store its songs. Using any computer, the teacher or parent can add different songs as well as record family members' voices to the SD card. Therefore, it is easy to create custom audio feedback to motivate the child. The device meets the design specifications given by our client and it is currently being used with children in the Morehead City area. Initial reports from therapists indicate that the device is very successful in motivating children to build upper body strength.

Student Author(s):	Stadler, Brian
Dept & College or University:	Mathematical Sciences, UNC-Greensboro
Research Mentor(s):	Jan Rychtar/Mathematical Sciences, UNC-Greensboro
Title of Presentation:	Evolutionary Dynamics on Graphs

Spatial structures can be used to represent populations of individuals, regardless of whether these individuals are humans, genes or cancerous cells. Graphs can then represent these structures and, after applying evolutionary dynamics, we can simulate changes within these populations. However, differing sizes of population and graph structure give rise to a struggle between natural selection and drift. To explore this we study the simplest possible question: what is the probability that a newly introduced mutant generates a lineage that takes over the whole population? From the results we will see that evolutionary dynamics act on populations. Individuals don't evolve, but rather populations.

Student Author(s):	Stewart, Luke J.
Dept & College or University:	Mathematics, Duke University
Research Mentor(s):	Arlie Petters/Mathematics; Physics, Duke University
Title of Presentation:	Planar Whitney Singularies with Applications

Singularities of mappings between planes arise when the associated Jacobian matrix is singular. When a mapping between planes is locally stable, its singularities are called "planar Whitney singularities." The goal of my project is to classify mathematically the latter singularities and determine their magnification cross section scalings. Applications will be given to computing magnification probabilities in gravitational lensing.

Student Author(s):	Sykes, Christian
Dept & College or University:	Mathematical Sciences, UNC-Greensboro
Research Mentor(s):	Jan Rychtar/Mathematical Sciences, UNC-Greensboro
Title of Presentation:	Stealing's for the Birds: A Model of Kleptoparasitism

The stealing of food resources, or kleptoparasitism, commonly occurs within the context of intraspecific competition, particularly amongst seabirds. The work here follows several recent papers (e.g. Broom, et al.), in which this phenomenon is modeled for monomorphic populations using game theoretic methods. Of primary interest is the adaptive dynamics of this model; in particular, under what conditions the populational strategy will converge to a given strategy and whether such a strategy is stable. Under the food model introduced in Rychtar & Broom, it is shown that only purely kleptoparasitic strategies may be stable.

Student Author(s):	Tucker, David J.
Dept & College or University:	Material Science and Engineering, NCSU
Research Mentor(s):	Carl Koch/Material Science and Engineering, NCSU Khaled Youssef/Material Science and Engineering, NCSU Ron Scattergood/Material Science and Engineering, NCSU K.L. Murty/Material Science and Engineering, NCSU
Title of Presentation:	Mechanical Properties of Nanocrystalline Alpha Brass (70-30 at% Cu-Zn)

A bulk nanocrystalline Cu-30 atomic % Zn brass alloy was synthesized by an in situ consolidation mechanical alloying technique. The mechanical behavior of this alloy was investigated by microhardness and tensile tests and compared with a conventional cold rolled, half hard CDA 260 brass alloy of the same composition. The microstructure was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM).

Student Author(s):	Veety, Matthew T.
Dept & College or University:	Electrical and Computer Engineering, NCSU
Research Mentor(s):	Doug W. Barlage/Electrical and Computer Engineering, NCSU
Title of Presentation:	R.E.C.S. (Robust Electronic Communications Systems)

The RECS (Robust Electronic Communication Systems) project was designed to provide a means of teaching middle and high school students about the concept of complex impedance. Applications include analysis of the resonance frequency of a crystal radio and audio systems.

From basic circuit theory, we know that a signal or load can be mathematically represented by real and imaginary parts. These complex values can account for not only changes in the magnitude of a signal, but also the phase difference caused by the load. By utilizing the sampling features of a personal computer sound card and MATLAB programming scripts, a comparative-value program can be developed to yield the low-frequency impedance of a passive device or circuit.

Using a modified standard 2-channel audio cable, a single frequency sinusoid is generated by the program and output to the line out of the sound card, which is then sampled at the line in. Using a FFT (Fast Fourier Transform) the signal is first passed through an open circuit to measure the sampled original signal and then the signal is passed through the loaded line again analyzed by a FFT. The two calculated transforms can then be compared to find the complex impedance of the load.

My research was focused on the validity and practicality of this model and experimental technique. The results of this research will be applied to a senior design project to be fully developed in the spring semester of 2006.

Student Author(s):	Ward, Catherine L.
Dept & College or University:	Biomedical Engineering, NCSU
Research Mentor(s):	Michelle E. Wall/Biomedical Engineering, NCSU and UNC-Chapel Hill Elizabeth G. Loboa/Biomedical Engineering, NCSU and UNC-Chapel Hill
Title of Presentation:	Isolation and Characterization of Mesenchymal Stem Cells from Human Trabecular Bone

Adult human mesenchymal stem cells (hMSCs) can be isolated from bone marrow, trabecular bone, and adipose tissue. This study illustrated the isolation and characterization of hMSCs obtained from extraneous trabecular bone fragments from orthopaedic procedures. Bone fragments were digested with collagenase type XI to release cells from the matrix. Cells were cultured in Minimum Essential Media Eagle, alpha modified, supplemented with 10% fetal bovine serum, 1% penicillin/streptomycin, and 2 mM L-glutamine until they reached 70-80% confluency. Cells were characterized by analyzing surface markers known to be present (CD73, CD105, and CD166) and absent (CD34 and CD45) in non-differentiated mesenchymal stem cells; and, by differentiation of these cells down osteogenic and adipogenic lineages. Surface marker expression was determined via immunohistochemistry. The cells were found to express CD105 and CD166. Additionally, the cells were differentiated down both bone and fat pathways by culturing the cells for two weeks in three media conditions: basal growth media, osteogenic media, and adipogenic media. Cells grown in basal media should remain in the non-differentiated state, whereas cells grown in osteogenic or adipogenic media should deposit calcium or produce lipid vacuoles, respectively. After two weeks, the cells were stained with Alizarin Red S, which stains calcium deposits, and Oil Red O, which stains oil droplets. The cells deposited calcium and oil droplets when cultured under their respective media conditions. Those cells maintained in basal growth media did not undergo either differentiation pathway. The results of these characterization studies indicate that the cells isolated from the trabecular bone are likely mesenchymal stem cells.

Student Author(s):	Whitlow, John L.
Dept & College or University:	Chemistry, East Carolina University
Research Mentor(s):	Yumin Li/Chemistry, East Carolina University
Title of Presentation:	Simulation of Novel Cancer Drugs: Using High Performance Computing to Predict Binding Affinity, Absorption, and Toxicity to Enhance the Process of Drug Discovery

Cancer is the leading cause of death for persons under the age of 85; its occurrence is expected to double by 2050. Consistent with cancer is elevated levels of the protein S100B. This research focused on the interaction between S100B and p53, the tumor suppressor protein. p53 ordinarily acts to initiate death in damaged cells. S100B disrupts p53’s function by binding to the low oligomerization states (monomer or dimer) of p53. This binding between S100B and p53 disrupts the tetramerization equilibrium of p53, disabling p53’s ability to check DNA for damage. This contributes to the formation of cancer. The purpose of this research was to design compounds to block the effects of S100B on p53. Compounds that enhance p53's cellular function may provide potent anticancer therapies.

One simple but powerful method for determining if a substance is “drug-like” in terms of absorption, distribution, metabolism, excretion ADME/toxicity is the “rule of five.” By reviewing a wide assortment of drugs, and analyzing overlapping attributes, it was determined that poor absorption is more likely when there are more than 5 H-bond donors, the MWT is over 500, the CLog P is over 5, or the sum of N’s and O’s is over 10. All of these values were a multiple of 5, hence the designation “rule of 5.” Compounds studied were prescreened for rule of 5 compliance. ADME/toxicity properties were also screened using ADMET Predictor. This software uses predictive neural network ensembles to derive regression relationships from documented properties found in large-scale studies. Additional ADMET Predictor models used as a final screening step included J-Alert, salmonella bacteria mutagenicity, and estrogen receptor toxicity.

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