Undergraduate Research Program

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Undergraduate Research Program fosters the creation and implementation of research, creative activities, service learning and community based scholarship for all undergraduate students. The unit is comprised of the Undergraduate Research Program(URP), the Community Engagement Initiative, the McNair Scholars Program, and the ArtsBridge Scholars Program.

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Effects of Stimulation Pattern and Frequency on the Ability of the Human Quadriceps Femoris to Produce Repetitive Dynamic Contractions
(2000-05) Turner, Amanda
This study tested the ability of sixteen different electrical stimulation trains to produce repetitive lower leg movements through a fifty-degree target excursion. Five constant-frequency trains (CFTs), five variable-frequency trains (VFTs), five doublet frequency trains (DFTs) and a high-frequency (lOOHz) burst were tested. The results indicated that the DFT was the most successful train type, and that the high-frequency burst was the most successful train overall. The repetitive doublet activation offered by DFTs may have stimulated force augmentation mechanisms many times within a train, therefore improving performance in fatigued muscle. In addition, the success of the high-frequency burst may have been due to activation of the same mechanisms responsible for force augmentation as those triggered by doublets.
Apolipoprotein C-I and Apolipoprotein E Production During Adipocyte Differentiation
(University of Delaware, 2009-05) Nguyen, Aivi T.
Cholesterol efflux, the process in which cells transport intracellular unesterified cholesterol to extracellular cholesterol acceptors, occurs late during adipocyte differentiation and involves secreted apolipoproteins which shuttle cholesterol to extracellular cholesterol acceptors. One apolipoprotein apoE produced by adipocytes, attaches to the cell surface through proteoglycan interactions, and plays an important role in cholesterol efflux to lipid poor HDLs. The Usher lab has discovered another apolipoprotein, apoC-I, which may also play a role in cholesterol efflux in adipocytes. The aim of this study is to (1) determine whether Apoe and Apoc1 mRNA expression is dependent upon intracellular cholesterol levels; (2) detect secreted apoC-I from adipocytes; and (3) address whether apoC-I associates with heparan sulfate proteoglycans on the cell surface, like apoE. To measure Apoe and Apoc1 mRNA expression Quantitative Real-Time PCR (QPCR) was used. Mouse 3T3-L1 fibroblasts were stimulated to differentiate and either not treated or treated with LXR agonist T0901317, β-cyclodextrin, serum-free media, or Intralipid. To access human APOC-I protein production, human adipocytes were grown on glass cover slips. The cover slips were either left untreated or treated with heparinase or heparinase and cell permeabilization. Cells were then visualized with rabbit anti-human APOC-I IgG and fluorescein isothiocyanate (FITC)-conjugated goat IgG. QPCR results demonstrated that Apoe mRNA expression reaches a maximum during on Day 3 of differentiation, or intermediate-phase differentiation while maximum Apoc1mRNA expression occurs on Day 6 of late-phase differentiation.LXR agonist treatments increased expression of both Apoe and Apoc1 mRNA, while cholesterol depletion with β-cyclodextrin and HDL decreased expression. Results indicated that Apoc1 and Apoe mRNA expression is sensitive to cholesterol levels. Epifluorescence microscopy revealed that human APOC-I is produced during late-phase differentiation (Day 6) on the adipocyte surface in a distinct punctate pattern. Moreover, after heparinase treatments, little APOC-I was visualized, suggesting that APOC-I attaches to heparan sulfate proteoglycans on the cell surface. APOC-I production during adipocyte differentiation and subsequent binding to heparan sulfate proteoglycans on the adipocyte surface suggests that it may act as a cholesterol acceptor in potential lipid rafts, similar to apoE.
Overcoming the Tides of Change: A Look at Globalization and the Italian Textile Industry
(University of Delaware, 2009-05) Zlatkus, Amanda
Globalization is an unstoppable trend which leads to a freer global market. The Italian textile and clothing industries are now facing greater competition from developing countries that have a comparative advantage in unskilled labor-intensive manufacturing, namely China. This study focuses on the impacts that globalization has had on the Italian textile and clothing industry and discusses recent trends in business operations, structures, and strategies and WTO trade regulations surrounding this industry. The findings of this study indicate that globalization has had a negative impact on those Italian textile and clothing manufacturers catering to the mid-market while those which utilize greater skill-intensive labor, and cater to high-end consumers, continue to survive. This study concludes that, in order to remain competitive in the global market, Italian textile, clothing, and fashion industries must shift their target consumer base to high-end consumers, for which Italians have a clear competitive advantage.
Integrating Services for Victims of Intimate Partner Violence into Mediation Centers
(University of Delaware, 2009-05) Aufschauer, Emily
This thesis proposes replication of the protocol of the Mediation Center of Dutchess County, New York, which is the only mediation center in the United States to offer counseling services for victims who have a history of intimate partner violence and are seeking divorce and/or child custody agreements with their spouses. As the practice currently exists, couples with a history of intimate partner violence can seek resources specific to ending the violence or specific to obtaining a divorce through the formal judicial system. If a couple who has a history of intimate partner violence wants to go to a mediation center instead of going to court to resolve issues surrounding a divorce or child custody agreement; however, they are screened out and referred to programs for offender rehabilitation or victim counseling. This thesis argues that the gap in services for recovering victims and perpetrators of intimate partner violence could be best served by restorative-justice-based alternative dispute resolution in the style of the protocol of the Mediation Center of Dutchess County, New York. After a brief review of the literature on intimate partner violence, chapter one outlines the history of policies pertaining to intimate partner violence as well as my own insights developed in direct observation of the experiences of victims of such violence within the criminal justice system. Chapters two and three discuss scholarship on restorative justice and alternative dispute resolution as it pertains to the described population. Chapter four includes the interviews with four practitioners who discuss possible obstacles and specific suggestions for integrating counseling into mediation centers. Chapter five outlines applied lessons from the literature and from interviews on how the proposed mediation centers would run.
Multivariate Analysis of the Fluorescence Decay of 3-Hydroxyflavone in Various Solvents
(University of Delaware, 2009-05) DeSario, Douglas Y.
The photokinetic parameters of the fluorescence decay of 3-hydroxyflavone were determined in six solvents, which were chosen for their widely differing polarities, dielectric constants, and hydrogen bonding capabilities. This was accomplished by the separation of three-dimensional time-resolved emission decay matrices through multivariate analysis. Particular attention was paid to the dual fluorescence of the main conformers of 3-hydroxyflavone – the normal and the tautomer – which forms the basis of the use of this molecule, and its derivatives, as fluorescent probes of solvent properties. The normal fluorescence was found to occur strongly only in solvents with the capability to hydrogen bond with the 3-hydroxyl group, thereby slowing the Excited State Intramolecular Proton Transfer (ESIPT) reaction that, unhindered, partially relaxes the normal excited state to the tautomer excited state. The photokinetic parameters that were calculated were the average excited state lifetimes, their initial intensities, and matrices of rate constants that quantified both the decay of each conformer of 3-hydroxyflavone in the excited state, and also the influences of each conformer on the others’ fluorescence. These parameters, as well as the λmax of the individual conformers, compared favorably to previous studies of this molecule.
The Effects of Secondary Stationary-Phase Polymers on Adsorption and Transport in Ion-Exchange Chromatography
(University of Delaware, 2009-05) Petroff, Matthew G.
Recent attempts to improve the adsorption and transport properties of ion-exchange adsorbents have included the modification of the adsorbent base matrix with a secondary polymer layer. This work attempts to characterize the relevant adsorption and transport properties of two related strong cation exchange adsorbents, Toyopearl GigaCap and Toyopearl SP-650M, which differ in that the GigaCap adsorbent consists of the SP-650M base matrix functionalized with a secondary-polymer layer. The studies performed utilized a combination of equilibrium adsorption isotherm determination, batch uptake, and isocratic pulse response experiments. Results were obtained for two model proteins, lysozyme (14.7 kDa) and lactoferrin (78 kDa), and were compared between the adsorbents to allow for elucidation of the effects of protein charge, protein size, and GigaCap’s secondary-polymer layer on the transport and adsorption behavior. The batch uptake results indicate higher effective pore diffusivities for lysozyme than for lactoferrin, but similar effective pore diffusivities for the respective proteins in the two adsorbents. The adsorption isotherms indicate that both proteins display much higher static capacities for the GigaCap S-650M particles than for the SP 650M particles. While the capacity differences are significant at low ionic strengths, they are drastically reduced at high ionic strengths, a trend that is more significant in lactoferrin than lysozyme. Retention experiments indicate decreasing retention between the protein-adsorbent pairs of lactoferrin on SP-650M, lysozyme on GigaCap, and lysozyme on SP-650M, as well as evidence of lactoferrin exclusion from GigaCap’s secondary polymer layer. Taken together, the adsorption and retention experiments indicate that lactoferrin is excluded from GigaCap’s secondary polymer layer high ionic strengths, and is partially excluded at lower ionic strengths. This exclusion appears to be a combination of steric effects, due to conformational changes in the polymer layer that reduce the accessibility for protein binding due to polymer shrinkage at high ionic strengths, and a decrease in the electrostatic forces that drive solute partitioning into the polymer layer. These effects are most significant at high ionic strengths, where lactoferrin is excluded from the polymer layer, but also appear at lower ionic strengths, where large differences in lactoferrin capacity are observed between ionic strengths of 20 mM and 50 mM. This exclusion behavior is observed for ionic strengths that are relevant for chromatographic process operations. It is thus important to be aware of these effects during process design, as relatively small ionic strength deviations may result in drastic changes in process performance. It is also relevant to future resin design, as it may be desirable to either reduce or exploit these effects in future adsorbents. Specifically, it presents an opportunity to design ion-exchange resins that have high affinity for ions of a specific molecular size range. It also demonstrates that changes must be made to the nature of the polymer layer before these adsorbents can display robust, high capacities for larger macromolecules.
Characterization and Cloning of the Human Perlecan Promoter Region
(University of Delaware, 2009-05) Richards, Matthew T.
Prostate cancer metastasizes preferentially to bone. The bone microenvironment presents the invading cells with a rich supply of growth and angiogenic factors. Because trabecular bone is in a state of resorption and deposition, the mineralized matrix is degraded and reformed constantly. This process also releases important growth factors, such as TGF-β, which may aid the survival of metastatic prostate cancer cells. Unpublished data from members of this lab group shows a large upregulation of a heparan sulfate proteoglycan, called perlecan, in the reactive stroma surrounding prostate epithelial cells. Perlecan is a structural protein located in the basement membranes and the matrix surrounding endothelial, mesenchymal and stromal cells. Among other properties, perlecan, through the heparan sulfate side chains, can bind growth factors. This property of perlecan identifies it as a protein that may help promote prostate cancer metastasis by providing the mobile cells with a scaffold to store growth and angiogenic factors in close proximity to their receptors. My project was concerned with the large upregulation of perlecan in the reactive stroma. I began my project by characterizing the promoter region for perlecan and identifying conserved transcription factor binding sites that could participate in transcriptionally regulating perlecan in prostate cancer. I identified several transcription factor binding sites of interest for further study, including NF-κB [-2410 to -2398], CREB ([-1797 to -1777] and [-709 to -689]), Smad3 ([-1301 to -1293] and [-187 to -179]), Elk-1 [-1699 to -1679], c-Jun ([-2453 to -2441] and [-2496 to -2476]) and TCF/LEF-1 ([-1521 to -1505] and [-1247 to -1231]). I then attempted to clone the promoter region from genomic DNA using polymerase chain reaction, and encountered several issues. I attempted to alter the reaction conditions and to try different kits to correct the problems. I found that addition of dimethyl sulfoxide to the reaction increased the specificity of the reaction and allowed for the successful cloning of the perlecan promoter region into a plasmid vector. Following the cloning of the vector, I began testing the effects of two growth factors, TGF-β and TNF-α, on perlecan transcription. Following treatment for 24 hours, RNA was extracted from HS27a bone marrow stromal cells and used to conduct quantitative PCR in order to test the levels of perlecan transcript. Although the data have not yet been analyzed, the cell cultures showed growth changes, namely the formation of a cobblestone growth pattern, which indicated that the growth factors affected some cellular processes. Further research needs to be conducted in order to determine if this effect indicates a change in perlecan transcription in order to determine whether perlecan could be a viable target for new therapies.
Ontogeny and Neural Substrates of the Context Pre-exposure Facilitation Effect on Contextual Fear Conditioning
(2009-05) Schiffino, Felipe
The essential mnemonic role of the hippocampus in contextual fear conditioning has been reliably demonstrated in the intact adult rat, and is believed to emerge around post-natal day (PND) 23. The mnemonic role mediates the conjugation of the individual feature representations of the context into a unified conjunctive representation, which can then be associated with the reinforcer. However, there is evidence that conditioning at the PND 23-24 may be typically supported by a feature-based simple associative system (SAS) that is hippocampus-independent. To address this issue, a variant of contextual fear conditioning that favors utilization of the hippocampus-dependent configural associative system (CAS) while minimizing contributions from the hippocampus-independent SAS was implemented early in ontogeny. This variant, termed the context-preexposure-facilitation-effect-of-the-immediate-shock-deficit (CPFE-ISD), involves exposure to context and foot shock on successive occasions. After various training parameter manipulations, the ability for the hippocampus-dependent variant seems to emerge rapidly between PND 17 and PND 24, and continues to develop to PND 31. Additional evidence suggests the mnemonic function at PND 24 is mediated by hippocampal long-term potentiation as antagonism of NMDA-type glutamate receptors in the dorsal hippocampus with dizocilpine blocked conditioning in the variant paradigm. This ontogenetic profile of the CPFE-ISD parallels that for conventional context conditioning, suggesting common neural substrates may control conditioning in both paradigms. This is important because the behavioral and neural mechanisms of conventional context conditioning are more variable and controversial than of the CPFE-ISD. Previously mentioned support for SAS-mediated conditioning at PND 23-24 may have been due to the protracted development of the SAS-inhibitory function of the CAS, relative to the mnemonic function, which clearly emerges by PND 24.
The Relationship Between Muscular Co-Contraction and Dynamic Knee Stiffness in ACL-Deficient Non-Copers
(University of Delaware, 2009-05) Gardinier, Emily S.
Anterior cruciate ligament-deficient (ACL-D) individuals who fail to dynamically stabilize their knee (termed non-copers) are reported to adopt a neuromuscular strategy characterized by reduced knee flexion excursions, reduced external knee flexion moments and generalized co-contraction during gait. This unsuccessful neuromuscular strategy has been qualitatively described as the “knee-stiffening strategy,” although dynamic knee stiffness has not been measured in the non-coper population. While the generally ascribed function of muscular co-contraction is to increase joint stiffness and stability, its relationship to dynamic knee stiffness during gait has not been evaluated. Establishment of a reliable relationship between these two measures would render stiffness a simpler means by which to infer co-contraction among individuals with ACLD knees. The purpose of this study was to determine (1) whether a strategy of generalized, increased co-contraction was present in the ACL-deficient limb, (2) whether ACL-D noncopers walk with a quantifiably stiffer involved knee and (3) whether dynamic knee stiffness correlates with muscular co-contraction in this dynamically unstable population. Kinematic and kinetic data were collected from 42 ACL-D non-copers (male, N=31; female, N=11; age, 27.8±10.1 yrs) during the weight acceptance phase of gait for calculation of dynamic joint stiffness. Electromyography for 6 lower extremity muscles (M/L vastus, M/L hamstring, M/L gastrocnemius) were also collected for determination of co-contraction indices. No significant differences in co-contraction indices and dynamic knee stiffness were found between the involved and uninvolved limbs in this sample. Furthermore, dynamic knee stiffness did not correlate with co-contraction during gait. The lack of elevated co-contraction in the ACL-D limb is contrary to recent reports in the literature. However, the lack of differences in dynamic stiffness between limbs suggests that during gait, absence of the ACL does not result in a quantifiably discernible “knee-stiffening strategy.” Because stiffness values did not correlate with co-contraction, we conclude that dynamic stiffness cannot be used as a surrogate for co-contraction during gait.
Reaping What’s Been Sown: Exploring Diaspora-Driven Development for Sierra Leone
(University of Delaware, 2009-05) Mello, Robyn Joanne
In September 2007, the post-conflict West African nation of Sierra Leone reached a turning point in its history. It has been experiencing the positive inertia which results from the first successful transition of government power since 1961. Members of Sierra Leone's Diaspora—its population living abroad—have been contributing to the momentum as individuals and small groups, but they are divided along many lines. Through the quantitative analysis of 250 survey responses and qualitative analysis of 31 follow-up interviews with Sierra Leoneans resident in the United States, direct participation in Diaspora forum discussions, knowledge from personal experiences in Sierra Leone and Ghana, and a literature review of Sierra Leonean history and African migration and development scholarship, this research is proof that the population has many common goals despite perceived differences. A report will detail their collective profile and make policy recommendations to maximize their potential for large-scale development throughout Sierra Leone that will decrease the country's dependency on outside assistance. Transnational migration, in which there is not one departure and one arrival but rather a more continual movement between locations, is becoming ever more popular in this age of globalization. Instead of creating a trend in which Sierra Leoneans only move back upon retirement in the United States, this research proposes a change in development work which will facilitate highly skilled, professional migrants of any age in a country's Diaspora to lead transnational lives, developing capacities in their places of birth alongside expatriate workers from international organizations and local communities. Sierra Leone should be a model country and a test case for these projects. To achieve the utmost success in Diaspora-driven development projects, migration scholars must put more emphasis on studying single populations rather than overarching theories and presuppositions which lump all migrants into categories which leave them seeming less than human or invisible.
Functional Identification of Shoulder Joint Centers
(University of Delaware, 2009-05) Monahan, Katherine
Analysis of upper extremity kinematics is difficult due to the lack of bony landmarks on the upper arm and shoulder. The medial and lateral epicondyles provide two potential bony landmarks for the upper arm, and the shoulder joint center provides a potential third landmark. Two methods commonly used to estimate the location of the shoulder joint center are the constant offset method (Rab, Petuskey, and Bagley, 2002) and the spherical fit method (Hicks and Richards, 2005). The constant offset method is susceptible to error due to variability of human geometry. The spherical fit method has been shown to be more accurate than constant offset methods for the hip; however, the methods have not been compared for the shoulder joint center. The objective was to compare the accuracy of the shoulder joint centers found using the functional spherical fit method as well as the constant offset method proposed by Rab, Petuskey, and Bagley (2002) relative to a physical measure of the shoulder joint center found using ultrasound. The physical measure was compared to the centers found with the constant offset method and functional identification for four positions: adduction-ER, 90º abduction-ER, 180º abduction-ER, and 90º flexion, IR. The centers were found for each method using the elevation of the humerus as a constraint. Specifically, motion trial data was analyzed at maximum elevation limits ranging from -30º below horizontal to 80º above horizontal at 10º intervals. Results indicated that the angle of elevation when using the spherical fit should be limited to zero degrees relative to the horizontal in order to minimize error. Using this minimized difference, the functional identification is most accurate in the adduction-ER position. Since both estimation methods are relative to the acromion marker, both are susceptible to errors in the other positions. In positions that require abduction, the scapula displays posterior tilt, resulting in the acromion rotating behind the glenoid cavity and causing the estimated centers to become posterior to the actual shoulder joint center. Conversely, in the 90º flexion-IR position, the scapula tilts anteriorly, causing the acromion to rotate in front of the glenoid cavity and produce estimated centers anterior to the actual shoulder joint center. Therefore, although the functional identification is more accurate in the adduction-ER position, both methods are characterized by substantial errors when implemented through a full range of motion.
Why the Court Said No: The Supreme Court’s Continued Opposition to Bush Administration Guantanamo Bay Policy
(University of Delaware, 2009-05) Christy, Andrew Chapman
In the wake of the terrorist attacks of September 11, 2001, actions taken by the presidential administration of George W. Bush fundamentally undermined the rule of law. This thesis examines a selection of these illegal actions within the context of the detention facility at the United States Military Base of Guantanamo Bay, Cuba. It was through the treatment of alleged terrorists held at the base that the Bush administration flaunted both the spirit and text of the law. By acting unilaterally, without the support of Congress, the President increased the authority of the presidency while attempting to undercut the traditional checks on power that have defined the United States federal government. Eventually, it was only the United States Supreme Court, in Rasul v. Bush (2004), Hamdan v. Rumsfeld (2006), and Boumediene v. Bush (2008) that was willing to defy its traditional deference towards a wartime president and restore the rule of law.
Export Taxation: The Case of Argentina
(University of Delaware, 2009-05) Dowd, William N.
This paper uses a partial equilibrium method to determine the welfareenhancing export tax level for Argentine soybeans, which is determined to be 25.29 percent. The actual export tax level on soybeans of 35 percent significantly exceeds the welfare-enhancing level, and the progressive export tax system that was in effect between March and July of 2008, due to a Presidential decree, set the rate even higher, at 44.1 percent. After examining the political and economic atmosphere in Argentina, I contend that the deviation between the optimal and actual tax rates can be explained by the government’s desire to generate additional revenue and protect domestic industry. Furthermore, the current administration’s policies clearly favor the industrial sector over the agricultural sector – two sectors of the economy that have historically been at odds with one another. The election of October 2007 showed the administration that they could win handily without the support of the farmers. This realization prompted the Kirchner administration to increase export taxes on soy twice, from 27.5 percent in November to 44.1 percent by March. Néstor and Cristina Kirchner, each of which has held the presidency, are focused on staying in power through electoral politics. Néstor Kirchner’s willingness to increase public expenditures at an abnormal rate during the election year to ensure his wife’s victory is obvious evidence of that. Export taxation is just another tool the Kirchners use to maintain the favor of their constituents in the industrial sector of the economy.
Experimental Characterization of In-Plane Permeability of Gas Diffusion Layers: Influence of the Saturation Level
(University of Delaware, 2009-05) Sedigh Haghighat, Amir Reza
Proton Exchange Membrane Fuel Cell or Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a promising energy conversion device due to its clean and efficient operation. Gas Diffusion Layer (GDL), a thin porous material, is one of its key components. It has been shown that by tailoring the GDL properties one can increase the PEMFC performance significantly. Characterizing the material properties is very important for material selection in a design process. The focus of this work is to experimentally measure an important property of the GDL material: permeability (or more specifically in-plane permeability, since the material is typically not isotropic). Water is the byproduct of the fuel cell reaction. During the PEMFC operation, water often condenses within the GDL pores thus hindering the gas flow and blocking the gas access to the reaction sites (catalyst layers). The main goal of our experiments is to measure the influence of the water content within the porous GDL (or, saturation) on the in-plane permeability. Convection is often a key mode of reactant transport, and its influence varies depending on the channel configuration. As the materials are porous, one can use the porous media theory of Darcy’s law to describe the convective transport for which one should first characterize the permeability of the material which is an input required in Darcy’s law which relates the flow rate through a porous material with the pressure drop experienced by the fluid. So convection is important and to model convection, one needs to measure permeability of the GDL. GDL is anisotropic; hence one must characterize in-plane (and through-plane) permeability. Water condenses in the GDL pores, so one must be able to describe permeability as a function of the saturation level. For the purpose of this investigation, the in-plane permeability of the dry GDLs was compared to the in-plane permeability of the wet (i.e. water-saturated) GDL’s for different saturation levels. . For future work, different types GDLs are to be compared to each other in addition to the effect of coating GDL with Teflon, to change the hydrophobicity level of the GDL, and its permeability and saturation level. Findings and results of this project include the measurements for plain carbon paper (TGP-H-060 by Toray Industries, Inc.). Due to several major problems, primarily coming from the complexity of the experimental setup, accruing more reliable data for the above GDL type, as well as comparing the data for different GDL types, has been postponed for the future. During the project, we have encountered several difficulties as follows: Scale malfunction, test stand inaccuracy, a number of hidden leaks in the plumbing of humid air, and condensation of water in the chamber manifolds. All the former problems have been addressed and the only problem left to solve to get very accurate data is to find out where water condenses in the tubes. This would help explaining less water collected at the end of the experiments compare to how much it is put in. The condensation problem is greatly reduced by running experiments with dry inlet air. Exponentially increase of permeability in the beginning of the run could be due to the water being pushed out by force rather than drying over time which is actually desired. Result curves start to smooth out for permeability around 40% saturation and flatten out until GDLs gets dry.
Quantitative Analysis of Breast Cancer Metastasis to the Brain
(University of Delaware, 2009-05) Teixeira, Kathryn
Previous experiments have shown that MDA-MB-231 human breast cancer cells could be injected into the extra-embryonic vasculature of chick embryos, and then cells which had metastasized to the brain could be isolated by drug selection. The sensitivity of the in vivo chick embryo system was tested by initially injecting embryos with a large number of cells (5x104) and then decreasing the number of cells injected tenfold to see if tumors would still form. Injections of 5x104 MDA-MB-231 cells produced an average of 186.6 colonies after treatment with G418, and injections 5x103 cells produced an average of 37.1 colonies. Experiments with nude mice have shown that re-injecting MDA-MB-231 cells which have been through the brain produced sublines with enhanced capacity to metastasize to the brain. In order to assess the effects of re-injection on cells, colony analysis was performed on serially injected cells. It was found that the average number of colonies detected decreased as cells were injected and recovered from the brain multiple times. It is speculated that the smaller colony numbers are due to cells dividing slower and forming smaller tumors, and not necessarily fewer cells extravasating to the brain, and re-injected cells are possibly entering a state of dormancy. Although I was not able to demonstrate that serial injection into chick embryos resulted in a brain-specific subline, as similar experiments did in previous mouse studies, this study has shown that the chick embryo is a useful model system for studying breast cancer metastasis to the brain. It has proven to be a sensitive system, as injection of only 5x103 cells resulted in measurable brain metastases. This system, along with colony analysis, will be useful for studying the effects of the manipulation of protein expression on metastatic capability in order to gain an understanding of the molecular mechanisms of metastasis.
Building a Relationship Between a University and its Surrounding Community: the Community Remembrance Project Revisited
(University of Delaware, 2009-05) Uehling, Katelyn
In their mission statements, many colleges and universities fail to include establishing a healthy relationship with their surrounding municipalities and neighborhoods. Yet maintaining such a relationship can help an institution prevent economic and legal fallouts. This project aims to explain the importance of building such university/community relationships through the analysis of the University of Delaware and its projects working with the New London Road Community, a once segregated African American community in Newark. The University has a history of an increasingly poor rapport with their African American neighbors, a situation which worsened as the university began to expand rapidly in the 1980‟s. When faculty at the University decided to embark upon a project to demonstrate the importance of art as social activism and the need to build relationships with surrounding communities, they chose to reach out to the African American community of New London Road. Their efforts culminated in the Community Remembrance Project, a joint effort by the Department of Fine Arts and Visual Communications and the Center for Material Culture Studies. The project began in 2004 and the aim was to recognize and honor the cultural roots of the New London Road African American Community. By working together with the citizens of the New London Road Community, the Community Remembrance Project produced a mosaic monument, a quilt, and two publications about the community‟s history. Along with the more tactile accomplishments the project also created a line of communication between the community and the University. When the mosaic monument fell to disrepair unexpectedly a few short years after being constructed, it became the mission of this project to find a new way to simultaneously commemorate the community and continue to strengthen the relationship between the University of Delaware and the community.
Investigation of Genetically Modified Soybean Oil for the Synthesis of Pressure Sensitive Adhesives
(University of Delaware, 2009-05) Zero, Scott
Pressure sensitive adhesives are polymer products that are ubiquitous in daily life. They are used in tapes, labels, films, and in many specialty adhesion applications. Demand for adhesives continually increases, and as this happens, it becomes increasingly important to search for a way to move away from petroleum-based starting materials. Such a shift could be performed by moving towards the adoption of vegetable oils for this purpose. Previous work in the Affordable Composites from the Renewable Sources group at the University of Delaware has demonstrated convincing evidence for the possibility of a shift toward the use of vegetable oils and their derivatives in the production of high performance products in the polymer science and chemical engineering industries. In line with this, a method has been developed for synthesizing monomers for pressure sensitive adhesive synthesis from methyl oleate. A mini-emulsion olymerization process, which reduces surfactant use and improves polymer properties over traditional emulsion polymerization, was developed and was shown to yield pressure sensitive adhesives with properties comparable to petroleum based adhesives, using acrylated methyl oleate as a monomer. The use of petroleum for the synthesis of pressure sensitive adhesives and other similar lowly cross-linked polymers has been estimated at 14 billion pound per year. If all pressure sensitive adhesives and similar polymers (including elastomers and coatings) were replaced with versions that use this bio-based technology, the fact that they are 70% bio-based would mean that there would be a reduction in petroleum usage of 10 billion pounds per year. High oleic soybean oil and olive oil were investigated as potential replacements for high purity methyl oleate as a starting product, which is prohibitively expensive. Proton nuclear magnetic resonance was used to determine the average number of double bonds per fatty acid in high-oleic soybean oil (0.9503) and to verify the purity of methyl oleate. The presence of polyunsaturated fatty acids in this oil was also verified. A new procedure that utilizes gas chromatography for the determination of the fatty acid distribution of oils, developed by MIDI Inc. (Newark, DE), was used to obtain a more comprehensive idea of the fatty acid distributions of high-oleic soybean oil and olive oil. The olive oil results agreed with literature, and the high oleic soybean oil results gave mole percent values for fifteen different fatty acids in the oil, and a very complete characterization, which was in close agreement with literature saturation profiles. It was found that the DuPont high oleic soybean oil consists of 85.53% monounsaturated fatty acids, 12.02% saturated fatty acids, and 2.15% poly-unsaturated fatty acids.
Music Education: is it Time to Go With the Flow?
(University of Delaware, 2009-05) Bersh, Brian David
Professional development for music teachers often occurs in short, unrelated workshops-rarely enacting change in practice. Therefore, the purpose of this research was to investigate elements that contribute to effective, sustained professional development for music teachers. Specifically, this study is an examination of the efficacy of a 90 clock-hour, immersion-based professional development cluster on steel pan through the unique lens of flow theory. According to Csikszentmihalyi (1991), flow is considered to be an optimal state in which skill and perceived level of challenge match. In the present study, music teachers’ (N=33) experiences in the steel drum professional development cluster were documented. The cluster was a 5-day period in which music teachers were immersed in learning how to play and teach steel pan. Data sources were participants’ daily journal reflections (N=137 entries), videotaped rehearsals (13 hours), interviews (N=7), and results from a follow-up satisfaction survey (N=25; 65% return). Csikszentmihalyi’s indicators of flow were used to code the data. Prevailing indicators of flow found to exist for the participants were immediate feedback, chance for completion, and high levels of interest/motivation. Findings suggest that the immersion context fostered participants’ growth in knowledge and skill for playing and teaching steel pan. Findings also suggest that immersion-based professional development promotes flow and has many attributes of an effective professional development paradigm.
Design and Characterization of Portable DMFC Power Supply System
(University of Delaware, 2009-05) Jacob, Cedric A.
The goal of this thesis is to provide an understanding of a practical portable direct methanol fuel cell (DMFC) stack system as well as produce a fuel cell stack that can be used for testing and demonstration purposes. DMFCs are relevant because of the high energy density that the fuel (methanol) affords. However, there are several key limitations — DMFCs suffer from greater activation, ohmic, and crossover losses than a standard Hydrogen Fuel Cell, as well as having a larger restriction on maximum current draw. This combination of advantages and disadvantages makes DMFCs very practical for the portable electronics industry. An attempt has been made therefore, to design and fabricate a DMFC stack that can be used in the Laboratory for testing purposes as well as attempt some innovative design modification with the hope of making either performance or size gains while keeping the stack practical and usable.
Can Abomasal Oligofructose Infusions be Used as a Model to Study Post-Ruminal Acidosis?
(University of Delaware, 2009-05) Mainardi, Sarah
Excessive microbial fermentation of carbohydrates in the large intestine of dairy cattle can result in post-ruminal acidosis and lead to laminitis, decreased reproductive success, and damage to the lining of the gastrointestinal tract. The objectives of the experiment were 1) to develop a model to study post-ruminal acidosis, and 2) to evaluate the potential for a dietary yeast supplement to alleviate post-ruminal acidosis. Six ruminally cannulated Holstein steers were used in a duplicated 3 x 3 Latin square experiment with 14-d treatment periods. Steers were randomly assigned to one of three treatments: (1) control, (2) oligofructose, and (3) oligofructose + yeast. Steers were fed a diet containing either 0 or 1 g/d Saccharomyces cerevisiae. On d 13 of each period, steers were abomasally infused with 1 L of water containing either 0 or 1 g/kg body weight of oligofructose. Fecal samples, blood samples, body temperature, heart rate, and respiratory rate were periodically collected for 48 hours after the abomasal infusion. The oligofructose infusion resulted in post-ruminal acidosis as indicated by a decrease in fecal pH and fecal score (P < 0.05). However, blood pH, temperature, heart rate, and respiratory rate were not affected, indicating that oligofructose-induced post-ruminal acidosis was likely sub-acute. Dietary yeast did not alleviate the oligofructose-induced decrease in fecal pH and fecal score. In conclusion, abomasal oligofructose infusion appears to be an effective model to study post-ruminal acidosis in dairy cattle.

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