Below is a list of titles of research projects conducted by MARC/AIM scholars in 2007. Click on each title to see an abstract of that project and the names and locations of the scholars and the faculty, staff and graduate students who mentored them. If you scroll down past the list of titles, the abstracts are arranged in alphabetical order of the MARC/AIM participants.
Electric Field Stimulation Model for Cortical Tissue Regeneration
Gabriel Albors, University of Puerto Rico at Mayaguez
Professor Pedro Irazoqui, Biomedical Engineering
While nerve cells in the brain were not previously thought to regenerate, recent studies show neuron regeneration after lesions in several regions of the cerebral cortex. In separate research, the application of dc voltage gradients within tissues of the spinal central nervous system has been shown to promote tissue development and repair. We hypothesize that miniaturized stimulator devices can be used to repair cortical tracts of parallel fibers damaged as a result of Traumatic Brain Injury (TBI) . In order to understand and evaluate how potential applied stimuli will propagate, we have developed an electrical model of the rat's brain. Our 3D COMSOL Multiphysics model uses Matlab to build up the geometry object. MRI images are loaded into the software to obtain a more accurate geometry that includes electrically important parameters about the brain, cerebrospinal fluid, bone, fat and skin. Domain equations are solved, and the boundary conditions, permittivity, conductivity and mass density are taken into consideration for better predictions. Following promising Phase I clinical trial results in human spinal cord injury recovery, we've moved back to the animal model and chosen the hippocampus as the site for a first attempt at cortical damage repair. The model will be able to accurately predict the distribution of applied fields and determine the current density best suited for regeneration. Predictions will be later confirmed through in-vivo measurement. Optimal electric field stimuli for propagation around the hippocampus are expected to be around 300uV/mm. The new model is a useful design tool for all manner of electrical prostheses in the rat's brain. We expect the application of the model-determined optimal stimulus will lead to gradual improvement in repairing damaged hippocampal tissue.
Establishing Inter-coder Agreement for the HOME Instrument
Evette Allen, Arkansas State University
Professor Steve Wilson, Department of Communication
The purpose of this project is to establish inter-coder agreement for a HOME instrument as part of a longitudinal evaluation study of a local intergenerational learning program. Intergenerational learning programs target educationally-disadvantaged families as a unit by providing early education programs for children along with parenting and literacy classes for their parents. A group of community stakeholders received a CAPE (Community Alliance to Promote Education) grant to establish a local intergenerational learning center and pursue four initiatives: an Early Care and Education Program (ECE), a Parenting Education Program, a Kindergarten Transition Program and an Evaluation Research Study. Sixteen (16) educationally-disadvantaged families were selected to participate in the ECE and parenting programs; families on the waiting list will serve as a comparison group. Data will be collected via questionnaires, surveys, interviews and home observations at three time points: program entry (baseline), 3-4 months after program entry and 1-year after entry. My role is to establish inter-coder agreement for the HOME (Home Observation for Measurement of the Environment; Bradley et al., 1975) instrument during baseline data collection. The HOME is a 45-question interview that assesses a child's environment in 6 categories: maternal responsivity, maternal acceptance, organization, learning materials, maternal involvement, and variety. A social worker conducts the home interview; she and I independently rate each family during the visit. Inter-coder agreement will be assessed via Scott's pi, which corrects for chance agreement among raters. The project will establish reliability for a key measure being used in the evaluation research.
The Phenomenology of Confronting Prejudice
Vincent Allen, Morehouse College
Professor Stephanie Goodwin, Department of Psychological Sciences
The Confronting Prejudiced Responses (CPR) Model (Goodwin, Ashburn-Nardo, & Morris, 2007) argues that the decision to confront prejudice is similar to the decision to help in an emergency situation. More specifically, people must: 1) notice the biased incident, 2) interpret it as an emergency, 3) assume responsibility for confronting the perpetrator , 4) decide how to confront, and 5) evaluate the costs and benefits before ultimately deciding whether to confront. The present study examines the conceptual validity of the CPR model. Ninety-six participants were recruited from the campus of a large Midwestern university. Participants first described a time when they observed another person being either kind, rude, or prejudiced and then explained their own reactions to the situation. Next, participants answered a series of items about the event, including questions about actors' characteristics (gender, race, etc.) and their relationship to the actors in the situation. Participants then responded to 36 items assessing the degree to which their experiences were characterized by the five factors identified in the CPR Model (noticing, interpreting, assuming responsibility, deciding how to confront, and evaluating costs and benefits). Data analyses are ongoing. Preliminary results are discussed.
The Role of Black Masons in 20th Century Atlanta Politics
Erica Burkhart, Elizabeth City State University
Professor Bob May, Department of History
Masons have been intimately involved in United States political history for centuries. In the 1920s fraternal orders shifted focus from religious and social affairs to civic and political duties. This project probes Black fraternal orders and their effect on Atlanta politics in the early twentieth century. Black Masons contributed to the Auburn Avenue ethos through their civic and political organizations such as the Atlanta Civic and Political League, the Atlanta Negro Voters League and the All-Citizens Committee. The relationship between the ideals of such groups and that of Black fraternal orders such as the Prince Hall Masons, Odd Fellows, Elks and Knights of Pythias is also examined. Primary and secondary sources such as the Atlanta Daily World , papers of Austin Thomas Walden and John Wesley Dobbs, and articles on black politics uncover the objectives and agencies of Masons in Atlanta racial affairs. Issues including white racialist opposition, the transition to consolidated, nonpartisan organizations from groups based on political affiliation and the role of Black-owned newspapers in local Atlanta campaigns are addressed. This project concludes that Masonic political leaders maintained proletariat outlooks despite elitist derivations, that unification of the black vote was symptomatic of the transition to nonpartisan political clubs and that the motivation and success of Atlanta Masons counters the argument that secret societies were only traditional in practice.
Effects of Deliquescence on Vitamin C Stability
Morgan Carter, Alabama A&M
Professor Lisa Mauer, Department of Food Science
Vitamin C is and essential nutrient for humans and must be obtained from the diet or supplements. The recommended dietary allowance for vitamin C in adults is 75 mg/day for women and 90 mg/day for men. During the processing and storage of foods or supplements, much of the vitamin C is lost due to oxidation, which is accelerated by light, oxygen, heat, increased pH, and/or high moisture content (water activity). This work presents the effects of moisture uptake and deliquescence, a solid to solution phase transition characteristic of water-soluble crystalline substances, on vitamin C stability. Seven different brands of supplements containing vitamin C (3 multivitamins, 3 vitamin C supplements, and one antioxidant blend) were placed in humidity controlled chambers at different relative humidities (98%, 85%, 75%, 64%, 54%, 43.1%, 0%). Mass gain, indicative of moisture uptake, was tracked over time (up to 39 days). The chemical stability of vitamin C was determined using the indophenol titration method. A gradual increase of mass was observed for all vitamins in each tank except for the chambers with a RH at 43.1% and 0%, thus increasing storage RH increases the amount of water present in vitamin C supplements. Vitamin C was less stable at higher RHs. For example, 100% of was lost after 1 week of storage at 98%RH. These results will be useful for setting storage, formulation, and packaging guidelines for vitamin C supplements.
Reevaluating the Nutrition Transition Across Countries and Time using Foster-Greer-Thorbecke Indices
Jenny Chan, Bryn Mawr College
Professor Will Masters, Department of Agricultural Economics
This project applies new statistical techniques to characterize the full distribution of nutritional status across a wide range of populations, and then test the determinants of changes in those distributions. Traditional measures of underweight or overweight consider only the fraction of people who are above or below an arbitrary threshold. Our approach considers the fraction of people who are at every level of bodyweight, borrowing techniques from the income-distribution literature to provide more sensitive and meaningful measures of "nutritional poverty" in any given society. Our goal for summer 2007 is to collect and characterize a very large number of distributions from household surveys conducted around the world and over time, so that later we can explain changes in those distributions in terms of a country's economic and social circumstances. Doing so will offer significant new evidence to explain past differences across countries, and to guide policy intervention for the future.
A Survey of the Philosophy Born of Struggle
Kylen Clayton, The Evergreen State University
Professor Leonard Harris, Department of Philosophy
My goal upon entering the program was to widen my scope and understanding of the field of philosophy as well as to identify philosophical roots of anti-oppression and revolutionary work. In this project, I read The Philosophy of Alain LeRoy Locke, edited by Dr. Leonard Harris and The Philosophy Born of Struggle, edited by Dr. Leonard Harris. In addition to these, I read Cosmopolitanism: Ethics in a World of Strangers , by Kwame Anthony Appiah for which I wrote a review. I also watched six years (1994, 1995, 1998, 2004, 2005 and 2006) of film from the Philosophy Born of Struggle Conference, for each I wrote an abstract capturing major themes and debates of the year as well as a synopsis of each participant's main arguments. I also sat in on an introductory ethics course for the purpose of identifying my academic competence as compared to other undergraduate students. Having finished the project, I have a gained a great deal of confidence regarding my academic legitimacy, as well as a sturdy foundation upon which I may continue my work in the field of philosophy.
Synthesis of Aromathecins as Topoisomerase I Inhibitors: Determining the Optimal 14-Position Side-Chain Length
Brenda Cordero, University of Puerto Rico
Professor Mark Cushman, Department of Medicinal Chemistry/Molecular Pharmacology
Topoisomerase 1 is an enzyme involved in DNA relaxation prior to DNA replication. This enzyme is overexpressed in several human tumors, and thus is a target for anticancer agents. The “aromathecin” class of molecules is being developed as topoisomerase I poisons. These inhibitors act by intercalating into the DNA-enzyme complex and preventing the religation of DNA strands broken by the enzyme. In developing a structure-activity relationship for these molecules, the ideal length for substituents located at the critical “14-position” is being determined. Substituents located at the 14-position are proposed to hydrogen-bond to the enzyme amino acids, stabilizing the complex. Amines at this position have previously shown biological activity. A series of diamine analogues have been prepared from an aromathecin “core” molecule, with a range of 2-6 carbons between the two amine groups. A reaction of three steps was performed in order to obtain each aromathecin. Reaction of the “core” with mono-Boc-protected diamines followed by acid-catalyzed deprotection, yielded aromathecin salts. Several of these compounds still need to be deprotected and analyzed. Compounds were characterized by melting point, 1 H NMR, IR and ESIMS. Each compound will be tested for topoisomerase 1 inhibition and cytotoxicity against a variety of cancer cell lines.
Quality Assessment of Computational Models of Proteins
De’Rael Darling, Savannah State University
Professor Diasuke Kihara, Department of Biological Sciences
The tertiary structure provides valuable information for function of proteins. Despite the recent advances in experimental structure determination, the gap between the number of solved structures and sequenced genes still remains where computational prediction can play a significant role to fill it. We have conducted genome-scale protein structure prediction of the E. coli genome using several different methods. Quality assessment is crucial for practical use of the models for experimental biologists. Here we evaluated the computational models by two methods. One method that was used was the TAP score method, which takes a measure of the protein sequence to the structure compatibility based upon the main-chain torsion angle propensities. The second one is Anolea, which scores models with a Z-Score. The Z-Score is an evaluation of the non-local environment for each heavy atom in a protein. It assigns an energy value to each heavy atom (higher energy is bad) and then gives a score based on the sum of all the energy divided by number of atoms. In most of the cases, the evaluation by TAP and Anolea agreed with each other, but there are some models for which evaluation by TAP and Anolea disagree. This is because the two methods evaluate a protein model from different aspects. We will show examples of models of a good quality and discuss similarity and dissimilarity of the two evaluation methods.
Ab initio study of the effect of radical attack on the folding of Ala-Ala-Ala tripeptide
Carlos Diaz, U Metropolitina
Professor Joe Francisco, Department of Chemistry
The bending and folding that proteins undergo determine their tertiary structure which dictates their overall function. ß-turn is the particular folding of interest that along with other conformation structures (ß-sheet and a-helix) combine to form the proteins tertiary structure. Variations in several proteins secondary structures have been implicated as possible causes for many diseases including Alzheimer's, Creutzfeldt-Jakob, and mad-cow diseases. One of the causes for misfolding is due by the reaction between radical species and proteins. This study attempts to determine the most thermodynamically favorable location for radical attack and the resulting consequences on the inter and intramolecular forces that are essential to protein folding. Computationally based nethods using the Gaussian 03 program were utilized to investigate an Ala-Ala-Ala tripeptide model. The information demonstrated that a-carbon is the most susceptible to attack resulting in a greatest opening of the ß-turn structure. By determining where these reactions are likely to occur, future researchers may be able to develop more accurate computational models and better analytical methods tailored for the altered geometry.
Single Amino Acid Substitution in Cav1.2A843P and its Effects on Voltage Dependence of Calcium Channels: A Tool for Determining Differential Roles of Cav 1.2 and Cav 1.3 in Insulin Secretion
Danielle English, Monmouth College
Professor Greg Hockerman, Department of Medicinal Chemistry/Molecular Pharmacology
Voltage-gated calcium channels contribute to various physiological properties such as the contraction of cardiac vascular and skeletal muscle, the release of neurotransmitters by neurons, apoptosis, gene expression and hormone secretion. The overall aim of our research is to identify, characterize and contribute to the development of logical drugs that can modulate voltage-gated calcium channels such as Ca v 1.3 and Ca v 1.s. The elucidating of these channels can lead to better treatments for cardiovascular disease and type II diabetes. In previous research, Ca v 1.3 channels were found to be coupled to glucose-stimulated insulin secretion from INS-cells and are abundant in endocrine and neuron cells. On the other hand, Ca v 1.2 channels are abundant in cardiac muscle and have not been shown to be coupled to glucose-stimulated insulin secretion (Hockerman). Our ultimate goal is to construct a series of chimeric Ca v 1.2/1.3 channels starting with mutant Ca v 1.2/A843P in order to determine the regions of Ca v 1.3 that are critical for coupling to insulin secretion. The short term goal of this study is to confirm the uptake of our mutant A843P by using several screening techniques.
The Effect of Resveratrol on MCF-7 and MDA-231 Breast Cancer Cell Lines
Melanie Foster, Jackson State University
Professor Sulma Mohammed, Department of Comparitive Pathobiology
Breast cancer is the most common malignancy and the second leading cause of death among women of all ages. Resveratrol, a dietary supplement found in peanuts, the skin of grapes, red wine, and mulberries been studied for its usefulness as a chemopreventive agent. Studies have also shown that resveratrol functions to clear brain plaques, inhibit the flu virus, prevent heart and cancer diseases. Additional studies suggest that resveratrol is unique because of its ability to battle cancer at all three steps of the cancer process: initiation, promotion, and progression. Because conflicting reports have shown that resveratrol induces proliferation and apoptosis in breast cancer cells, we will examine this phenomenon. Estrogen receptor positive and estrogen receptor negative breast cancer cell lines, MCF-7 and MDA-231 respectively, will be treated with resveratrol concentrations ranging from 0.1 m M to 1000 m M using time-dependent dosages. MTT assays were completed and read at 570 nm but results are still inconclusive for our study. To date, our data show that resveratrol increases proliferation of MCF-7 cells. This study is still underway.
Chromatin Modifications and Their Effects of DNA Damage Repair and Silencing in Saccharomyces Cerevisiae
Tiaunn Foster, Jackson State University
Professor Ann Kirchmaier, Department of Biochemistry
Although chromatin structure plays important roles in gene expression, it is also imperative for processes such as DNA damage repair and epigenetic gene regulation. Previous research has indicated that modifications to chromatin are key to preserving genome integrity. Chromatin assembly factors and histone-modifying enzymes have been implicated in both DNA damage repair and gene silencing. Defects in chromatin assembly and histone modification disrupt pathways for repairing DNA damage and lead to the re-expression of inactive regions of the chromosome. In this study, we analyzed how modifications in chromatin effect DNA damage repair and silencing in Saccharomyces cerevisiae using mutations in histones H3 and H4 that mimicked either the modified or unmodified state of key amino acids. These mutants were analyzed singly or in combination with mutations in chromatin assembly factors and enzymes that modify histones. This synthetic interaction analysis uncovered both distinct and overlapping roles of chromatin modifications and chromatin assembly factors in DNA repair and silencing.
Surveying Lameness in Breeding-age Swine in Comparison of Methods to Assess Lameness
Carlos Garza, Purdue North Central
Professor Darryl Ragland, Department of Veterinary Clinical Sciences
The study focused on 3 critical objectives. The first was to determine the frequency of lameness in a large sample of sexually mature sows and gilts. The second objective was to evaluate sows and/or gilts for signs of lameness standing in gestation crates compared to that of walking soundness. The third and final objective was to make comparisons regarding the methods of evaluating every animal in the gestation facility for signs of lameness in opposition to an evaluation of a statistical sample as endorsed by the National Pork Board.
The research was conducted at a 1600-head swine farm located in southwest Indiana and the number of sows/gilts evaluated for signs of lameness in gestation crates totaled 360. The females were made to stand and were assessed for signs of lameness within the confines of the gestation crate. The females were than allowed out of their crates to walk upon a solid concrete surface to study their gait for decreased walking quality. Lastly, the reliability of every female was compared to the protocol suggested by the National Pork Board where a statistically relevant sample of females was evaluated.
Assessment of all sows/gilts standing in their crates revealed a lameness frequency of 12.2% (44/360). Evaluation of sows/gilts for walking soundness revealed a lameness frequency rate of 43% (77/180). Assessment of lameness using the National Pork Board protocol indicated that scoring every other crate would be sufficient (180/360). When lameness scores were tallied up for the gestation crates it totaled 19/180. That comes to 10.5% for lameness and it was not too far off from the 12.2% found by checking every crate (360/360). The difference between the two percentages comes out to 1.7%.
Based on the results of the research, thorough evaluation of sexually mature females for lameness may require the assessment of animals standing in gestation crates along with the animal walking a slow, steady pace for potential gait abnormalities. The results of the study also suggest that the evaluation of lameness using the National Pork Board protocol may be in the best interest of the observers.
15Specifying Features of AR Systems for Field Supervision in Construction
Lauren Johnson, Loyola Marymont University
Professor Philip Dunston, Department of Civil Engineering
Augmented Reality (AR) systems superimpose virtual objects onto a real world background for the purpose of enhancing an individual's ability to operate in a specific real world environment. This technology is used in many different arenas such as filmmaking, television, and military training. This study concentrates on the use of AR in construction tasks that demand that designs be interpreted to 3D space. Prior research conducted at Purdue University on the use of an AR system for construction inspection revealed that the AR prototype designed for that task could be useful in the field for that purpose. An alternative focus for research with this prototype is construction supervision, which involves the evaluation of progress and quality throughout the construction process. Inspection is similar to field supervision in that the inspector examines the "product" of an activity and either gives approval or demands corrective action. The construction supervisor is responsible for ensuring that all elements of the project are constructed properly within schedule and with a particular level of quality so that milestones are met and rework is avoided. Therefore, the AR system used for supervision should exploit links between the digital design and time as reflected in the planned schedule. Construction supervisors typically use separate 2-dimensional paper displays of plans or shop drawings and printed schedules to monitor the performance of construction activities. The envisioned AR system for supervision should have the capabilities to display shop drawings and plans to the supervisor for detail checks as well as present, perhaps by superposition, the planned progress of a large construction task for direct visual comparison to the real structure. This study is now addressing the proposed design and advantages of the use of this AR system over current practice, and will examine its impact on construction supervision in the future.
Effects of Tamoxifen and 4-hydroxytamoxifen on Growth of MCF-7 and CRL 1743 Mamary Tumor Cells
Brandi Jones, Jackson State University
Professor Ignacio Camarillo, Department of Biological Sciences
Breast cancer is the most common cancer in women in Western civilization. In addition, obesity is attributed to increased incidence and aggressive forms of breast cancer. Tamoxifen is the world's largest selling breast cancer drug used for treatment of primary and metastatic diseases in pre- and post-menopausal women. In breast cancer cells tamoxifen suppresses estrogen stimulated gene expression, which leads to cytostatic or apoptotic effects, depending on its concentration. The major metabolites of tamoxifen in humans are N -desmethyltamoxifen an trans -4-hydroxytamoxifen; the affinity of the latter for estrogen receptors is equivalent to that of 17 b -estradiol. We hypothesize 4-hydroxytamoxifen will inhibit cell growth to a greater extent than Tamoxifen in both human and rat derived cell lines.
In this study we examined the effect of Tamoxifen and 4-hydroxytamoxifen on the growth of human (MCF-7) and rat (CRL-1743) cell lines. In brief, MCF-7 and CRL-1743 cells were treated with 1x10 -10 - 1x10 -5 M Tamoxifen or 4-hydroxytamoxifen for 24 and 48 hours. Treatments were conducted in medium containing charcoal stripped serum and supplemented with estradiol. We observed a dose dependent decrease in cell growth at 24 and 48 hrs in both MCF-7 and CRL 1743 cell lines with Tamoxifen and 4-hydroxytamoxifen. These studies provide evidence that Tamoxifen and 4-hydroxytamoxifen are useful in the suppression of tumor growth in CRL-1743 cells. This provides a foundation for testing these drugs in an in vivo rat model of obesity and breast cancer.
Synthesis and Targeting of Folate-Conjugated Near IR Dyes to Atherosclerotic Lesions
Alexandra Mendez, University of Puerto Rico at Aguadilla
Professor Phil Low, Department of Chemistry
Atherosclerosis is among the greatest public health issues affecting Western societies and developing countries. Activated macrophages play a pivotal role in the initiation and development of atherosclerosis, which in advanced stages can lead to adverse cardiovascular events that can impact lifestyle or even cause death. A subset of activated macrophages over-express a GPI-anchored protein called the folate receptor, which has previously been used to target folate-conjugated compounds and/or drugs to areas of active inflammation. Recent evidence suggests that folate-receptor-positive macrophages are found within the plaque in atherosclerotic lesions, opening the door for using folate-targeting as a tool for diagnosis and treatment of atherosclerosis. We have synthesized and characterized a folate conjugate of a near-infrared dye (DyLight TM 680) and tested its potential in the diagnosis of atherosclerosis in mice. By employing fluorescence imaging, we have demonstrated specific uptake of folate-DyLight TM 680 in the thoracic cavities of diseased but not healthy mice. Fluorescence microscopy of aortic thin sections of mice to which folate-DyLight TM 680 was administered also reveal that atheroma-localized monocyte/macrophage lineage cells take up the folate-dye conjugate. Future studies will be aimed at evaluation of folate-conjugated drugs for the treatment of atherosclerosis by the eleimination of the folate-receptor-positive macrophages in atherosclerotic lesions.
Using a modified sodium tetraphenylboron procedure to determine nonexchangeable ammonium and potassium in soils
Blucher Menelas, Iowa State University
Professor Brad Joern, Department of Agronomy
Effective crop management to obtain full yield potential usually involves fertilizer applications. These recommendations are driven by soil tests that dictate application rates. Traditional soil tests for potassium (K) do not measure potentially available nonexchangeable K present in the interlayers of many clay minerals, and no routine soil test is available for measuring potentially plant available nonexchangeable ammonium (NH 4 + ) in soils. Eighteen soil samples from Indiana that were either left untreated or were saturated with NH 4 + and K + . We extracted these soils with a modified sodium tetraphenylboron (NaBPh 4 ) procedure to determine the amount and variability of existing pools of nonexchangeable NH 4 + and K + in these soils and the fixation potential of these soils for NH 4 + and K + . We expect to show that the NaBPh 4 method can be used to quantify nonexchangeable NH 4 + and K + pools in soils and that this method can be used to differentiate soils that have either large or small amounts of nonexchangeable NH 4 + and K + . The results from this study will be presented at this conference.
Evaluation of the role of EphA2 activation in breast cancer therapeutics using adenoviral vectors
Eythan Morenu, University of Puerto Rico at Aguadilla
Professsor Suresh Mittal, Department of Comparitive Pathobiology
O verexpression of the receptor tyrosine kinase, EphA2, occurs in the majority of invasive breast cancers, and successful binding of its ligand Ephrin-A1 has been shown to restore normal cellular functions. In normal breast cells and other adult epithelial cells, EphA2 is expressed at considerably low levels and is associated with its ligand, whereas, in breast cancer cells EphA2 is overexpressed and its significant amounts are not associated with its ligand. Therefore, EphA2 provides a unique cancer cell target for breast cancer intervention. We have generated a human adenoviral (HAd) type 5 vector that expresses secreted-form of EphrinA1 (HAd-EphrinA1-Fc) . We have already shown that infection of MDA-MB-231 human breast cancer cells with HAd-EphrinA1-Fc resulted in increased EphA2 activation and turnover and consequently decreased tumor cell viability in suspension culture. Consistent with this observation, infection of MDA-MB-231 cells with HAd-EphrinA1-Fc prevented tumor formation in a nude mouse xenograft model. In addition, we have demonstrated that FVB/n mice-bearing MT1A2-induced tumors could serve as an immunocompetent mouse model of breast cancer for EphA2-targeted therapeutic strategies. In this project we plan to evaluate the role of EphA2 activation by EphrinA1-Fc in inhibiting tumor growth by monitoring levels of apoptosis and expression levels of pro-apoptotic and, anti-apoptotic
genes in MDA-MB-231 and MCF10Acell lines infected with Had-EphrinA1-Fc as compared to control. We also plan to measure the activation of certain signal translation molecules of EphA2 pathway, mainly FAK and ERK1. We expect a significant increase in apoptosis and levels of expression of proapoptotic genes and a decrease in anti-apoptotic genes in MDA-MB-231 cells infected with Had-EphrinA1-Fc as compared to control. These results will further help to address the possibility of future therapy developments using Ephrin-A1 to restore normal cellular functions.
Efficacy of Ozone against Indianmeal Moth
Hassan Mussa, Florida A&M University
Professor Linda Mason, Department of Entomology
Indianmeal moth ( Plodia interpunctella Hübner) is a very common pest of cereals and dry grain products from the farm gate to the consumer, resulting in millions of dollars of losses each year. Larvae, the primary feeding stage, are the most destructive. Organic produces and many consumers desire alternative control strategies for managing this destructive pest rather than traditional residual pesticides. Ozone has shown promise as a non-residual control strategy for stored food products, demonstrating efficacy against such major pests as storage weevils and beetles. Little work has been done on clarifying this control strategy with moths.
Indianmeal moth egg, larvae and pupae were treated with various ozone time/ concentrations combinations. Concentrations tested ranged from 50-1500 ppm ozone (50, 100, 500, 1000, 1500) while two time periods were tested (30 and 60 min).
Eggs achieved highest mortality at 60 min/1500 ppm; larvae at 30 min/1500; and pupae at 60 min/1500. These results indicate that eggs and pupae are more resistant to ozone than larvae. This is not unexpected considering eggs and pupae have a lower respiration rate compared to larvae. Since 100% mortality was never achieved for any life stage at any time/concentration tested, it is obvious that we need to investigate longer times or higher concentrations to achieve complete control.
Spatial Regulation of Raf-1 Activation Following T Cell Activation
Shanel Pruitt , Alabama Agricultural and Mechanical University
Professor Marietta Harrison, Department of Medicinal Chemistry/Molecular Pharmacology
Lck, a Src family of protein tyrosine kinase, plays a pivotal role in the development and activation of T-cells. Individuals lacking functional T-cells fail to develop immune responses to antigens. Lck functions to transmit signals from the T-cell receptors to the nucleus through the Ras/Raf-1/MEK/ERK MAPK pathway. Recent studies in our laboratory suggest that Lck is localized to the plasma membrane and Golgi apparatus. Following activating signals from the T-cell receptor, Raf-1, a serine/threonine kinase, is tyrosine phosphorylated by Lck for full activation and transmission of signal to the nucleus. We hypothesize that Lck phosphorylates Raf-1 on the Golgi. The aim of this project is to study the cellular localization of Raf-1 in T-cells following T-cell activation. This will be achieved through transient transfection of Raf-1 followed by immunostaining analysis to observe Raf-1 expression and localization.
Chemical Derivatization of Carboxylic Acids in Biofluids for Improved Detection of Biofluids Metabolites Kellymar Rosa, University of Puerto Rico, Rio Piedras
Professor Daniel Raftery , Department of Chemistry
Metabolite profiling, or metabolomics, provides detailed metabolic information on biological samples for a range of applications including early disease detection, following treatment, and the evaluation of drug toxicity and efficacy. Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) are the analytical techniques most often used for the bio-analytical applications of metabolomics. NMR is widely used because it provides a rapid, non-destructive and quantitative method of chemical analysis that requires minimal sample preparation. 13 C NMR is not highly utilized in metabolomics, due to its low sensitivity (1.1% natural abundance) leading to long experiment time. The objective of this research is to develop and apply 13 C NMR for the analysis of metabolites in biofluids such as serum and urine. A new approach for enhancing the sensitivity of 13 C NMR is to derivatize a particular class of metabolites of interest in a complex mixture using a 13 C isotopically enriched reagent. The Raftery group has already been successful in derivatizing amines and amino acids using acetic anhydride as the reagent. Carboxylic acids represent a class of metabolites present in biofluids at low concentrations which often show elevated levels in biofluids under different disease or dietary conditions. The chemical derivatization of carboxylic acids in DMSO with 13 C isotopically labeled methyl iodide yields the corresponding 13 C-labeled methyl esters. An attractive feature of this methodology is the ability to monitor numerous metabolites of complex mixtures in a single process with high resolution and improved spectral simplicity. This methodology was used in the identification of carboxylic acids in complex mixtures, including urine and human serum samples.
Playback Responses of the Carolina Chickadees and White-breasted Nuthatches: Results of Playback Responses
Anthea Saez, Purdue Calumet
Professor Jeff Lucas, Department of Bio/Vet Medicine
Interspecies relationships occur amongst birds for multiple reasons; one function is for protection against predators. Safety of the nests and each other is so important that species mutually share anti-predator behaviors. One device that is used for protection is “Mobbing”, which involves a sighting of a predator by a single bird which in turn sends an alarm call and in turn calls different species of birds to the area of the predator . This action causes the birds to harass the predator and the goal is to harass the predator enough in order for it to leave the area. Protection is the key to interspecies specific relations in birds.
Species differ in their values of mobbing, such as it being more valuable to birds with small home ranges and there are fewer foraging sites that predators are not in the territory. The cost of mobbing a predator should decline with an increase in flock size since the predator only takes one prey. We incorporated both species and number effects in a playback design where one or two mobbing calls from chickadees or nuthatches, or both were broadcasted along with a model owl. Analysis included reviewing the responses by counting the number of calls made by each species and the distance of the birds along with their actions. The more calls, the closest distance and the more actions made toward the owl will determine how intense the response was. Results should show that with the solitary playbacks that the first to respond to a chickadee call will be a chickadee and the first responder of a nuthatch call will be a nuthatch. The more birds that are mobbing the more response should occur, so the two of each playback will show the most response.
Constructing race in Campaign 2008: A textual analysis of the PBS All American Presidential Forum featuring the Democratic candidates at Howard University
Shavonne Shorter, Frostburg State University
Professor Stacy Connaughton, Department of Communication
History was made on June 28, 2007 when candidates for United States presidency for the first time debated exclusively about race. This article provides a close textual analysis of the first PBS All America Presidential Forum featuring the Democratic candidates for United States President, to discover how these individuals construct race. We find that candidates constructed race in this debate as a direct synonym for African Americans. Additionally, African Americans are being constructed by the candidates as poor, lacking education, and destined for failure. Implication of these constructions for discourse about race and politics in the american political campaign context, as well as for how African Americans may view themselves vis-a-vis the U.S. political system, are discussed.
Ballooning of America : From a Mathematical Perspective Toni Tullius, St. Mary's University
Professors Carl Cowen and Fabio Milner, Department of Mathematics
If one were to look around they will see America gradually getting bigger, not only in population size, but in body mass as well. According to the National Institutes of Health, obesity is the second leading cause of preventable deaths in the United States . In hopes of spreading the importance and reality of this epidemic, we attempt to use mathematical modeling to describe the long term effects of the social interaction among various subgroups of the population on the occurrence of obesity in our society. Mathematical models are created to help understand the development of the epidemic by analyzing data and formulating predictions for the future. For the model, we developed ordinary differential equations to describe the way in which various subgroups of the population change over time due to their interaction amongst each other. We defined sixteen population subgroups that represent individuals who are categorized as underweight, healthy, overweight, and obese as well as incorporating age groups within these categories: child, teenager, adult, and elderly, and each of the subgroups are associated with a differential equation in the system. From these models we provide data of possible outcomes due to the rise in obesity.
Synthesis of Aminated ß -Cyclodextrin for Polyrotaxane for Gene Delivery
Angela Van Buren, Southern University
Professor David Thompson, Department of Chemistry
Gene therapy is a method that allows treatment of diseases by inserting therapeutic genes into a person's cells. For a successful gene delivery to occur, the DNA needs be condensed to enable it to enter the cell. Once inside the cell, it must be decondensed and enter the nucleus where it can be transcribed and/or integrated into the host cell genome. This project focuses on the synthesis of cationic polyrotaxanes for use as condensing agents to facilitate DNA delivery into the target cell cytoplasm. The polyrotaxane consists of a polymer chain of polypropylene glycol, aminated b -cyclodextrin, and endcaps to stop the cyclodextrins from dethreading off the polymer chain. Cyclodextrin is a cyclic oligomer that consists of 6, 7, or 8 glucose units. In the lab, b - cyclodextrins are aminated to promote complexation between the negative phosphate backbone of DNA and the cationic groups on the polyrotaxane cyclodextrin units. The polyvalent electrostatic interactions between the cationic polyrotaxane and the anionic DNA plasmide produces small transfection complexes known as ‘polyplex'.
Preparation of 1-(p-Toluenesulfonyl)imidazole had an average yield of 53.3%. The average yield for the synthesis of 6 A -O-toluenesulfonyl- ß -cyclodextrin was 37.1%. 6 A Amino- b -cyclodextrin was produced with an overall yield of 3.81%, while 6 A -N-ethylenediamine- b -cyclodextrin was produced in a 23.5% yield.
Examination of the reaction mixture by thin layer chromatography showed that highly pure cationic cyclodextrin was obtained from these reactions. Efforts are now underway to form polyrotaxanes from these aminated cyclodextrins. Subsequent efforts will then focus on the formation of rotaxane/DNA polyplexes. These polyplex will then be used in transfection studies.
Influence of neurotrophic extracellular matrix peptides on neurite outgrowth in hyaluronic acid hydrogel in vitro
Catherine Whittington, Louisiana Tech University
Professor Alyssa Panitch, Department of Biomedical Engineering
In the United States , new cases of spinal cord injuries (SCI) affect approximately 28-50 per one million people annually. Affected individuals may experience complications such as a loss of physical mobility and sensation, development of decubitus skin ulcerations, and diminished capacity to control bladder and bowel functions. The central nervous system (CNS) typically lacks the ability to spontaneously repair itself post-injury, and biomimetic scaffolds can be used as a therapy to treat SCI by providing mechanical support and cell signals to facilitate nerve regeneration. Hyaluronic acid (HyA) hydrogels, made with cross-linked thiolated HyA and poly(ethylene glycol) diacrylate, have supported neurite outgrowth during in vitro studies and can function as a potential replacement for the spinal cord extracellular matrix (ECM) post injury. HyA, a glycosaminoglycan ECM component, is ubiquitous in tissue and contributes to regulatory processes within cells, including proliferation and signaling. To determine the effect of neurotrophic peptides on neurite outgrowth, a thiolated peptide sequence, CINPISG, from an N-cadherin molecule was incorporated into HyA hydrogels. Embryonic rat cortex cells were cultured in 1% HyA hydrogels conjugated with 0, 0.7, 7, and 70 µM CINSPISG. The samples were incubated at 96-, 144-, and 192 hour time points, after which samples were imaged with confocal microscopy to determine the growth of neurite extensions. Rheology was performed to determine gelatin time, strength, and viscoelastic behavior of the hydrogels with and without peptide. According to the studies, addition of CINPISG increased gelation time when compared with the control but did not cause significant changes in the elastic modulus between any of the hydrogels.
The Identification of Unknown Compounds Containing Oxygen-Functionalities By Using Various Mass Spectrometric Techniques
Jamelle Williams, Tuskeegee Institute
Professor Hikka Kenttamaa , Department of Chemistry
The ability to rapidly identify unknown compounds in complex mixtures is highly desirable in pharmaceutical industry. Methods commonly used for identifying mixture components include IR and NMR. However, these methods are time-consuming since they usually require the isolation of the analyte. An alternative approach is tandem mass spectrometry (MS/MS) which allows the direct characterization of mixture components without isolation. Previously, MS/MS methods utilizing gas-phase ion-molecule reactions have been developed for identifying oxygen-functionalities in simple protonated analytes 1,2 by using Fourier transform ion cyclotron resonance (FT-ICR) and a triple quadrupole mass spectrometers. The research discussed in this talk focuses on the testing of the applicability of this method to more complex substrates, and its implementation to a linear quadrupole ion trap mass spectrometer. Some of the analytes examined behaved as expected, including 3-nonanone. The analyte was protonated by self chemical ionization, isolated, and allowed to react with trimethylborate (TMB) in a mass spectrometer. The results show that protonated 3-nonanone is derivatized by the expected addition/elimination reaction, which leads to loss of methanol. However, the reactions of some other analytes, including two steroids, estradiol and androsterone, did not proceed as expected. The reasons for this behavior are discussed.
Co-authors: Lindsey Kirkpatrick , Sen Li , Jayalakshmi Somuramasami 
Can the Incidence of HIV Decline if Infected Americans Reduce Risky Behaviors and Reproduction? A Mathematical Model Kristen Young, Clark Atlanta
Professors Carl Cowen and Fabio Milner, Department of Mathematics
Mathematical modeling–the process of creating a mathematical representation in an attempt to match observation with symbolic statements–may be a helpful tool for understanding some features of a system under observation. The process of mathematical modeling is used in many fields including biology and epidemiology, which includes the study of diseases such as HIV/AIDS. The model proposed here, which uses a system of ordinary differential equations, was based on a basic class of models known as SIR (the population consists of the disjoint classes (S)usceptible, (I)nfected and (R)ecovered individuals). An SIA (that is, (S)usceptible, (I)nfected with HIV, and diagnosed with (A)IDS) model is a modification and expansion of the traditional SIR model. The model has to account for all of the population and, in order to be accurate, the population has to be divided into several different groups. HIV/AIDS can be transmitted through many different paths; however, we focused in on male-to-male sexual contact, mother-to-child transmission, and heterosexual contact since they were the most important. Unlike many other SIA models, in this model we want to show that the non-reproductive class has an important impact in this epidemic as well as on the future population.
One-loop QCD Beta function in a Physical Gauge
Sannah Ziama, IUPUI
Profesor Martin Kruczenski, Department of Physics
The primary goal of this project is to elaborate on and understand the subtleties of the computation of the one-loop Beta function in Quantum Chromodynamics (QCD) in a physical gauge. In nature, there are four fundamental forces and these forces manifest themselves via four distinct interactions. Namely the Strong, Electromagnetic, Weak and Gravitational interactions. Our project is concerned with the strong interaction. In this realm, tiny particles of matter known as quarks interact by exchanging quanta of the Strong force called gluons. The situation is, to some extent, analogous to the more familiar electromagnetic phenomenon in which electrons are the particles of matter and they interact by exchanging photons, the quanta of electromagnetic force. Unlike photons, gluons can also interact with other gluons i.e. they can combine and also split up, meaning that when one gluon propagates from one quark to another one should take into account all possible processes where the gluon splits and rejoins into several other gluons. Customarily, these calculations have been performed by introducing unphysical polarizations of the gluon to simplify the calculations. Other approach considers, instead, only physical polarization which from a practical point of view has advantages but also drawbacks which we explore in some detail here.