SCCUR Title University of California, Irvine
 
     
 
   
   
     
 
     
 
     
 
   
   
   
     
 
 


  University of California, Irvine

Abstracts
November 22, 2003
University of California, Irvine


A-G    H-N    O-Z    Groups

Optimization of Robotic Elements Using CAD, CAM, and Rapid Prototyping

Marni Hager

Mentor: Behzad Bavarian

California State University, Northridge

Robots today perform a variety of work from space exploration on Mars to Search & Rescue work. Exploration and Search & Rescue robots work in situations that present unique challenges for engineers trying to optimize robotic movement. These robots require enough torque to navigate over obstacles and sufficient speed to cover a large area. Complicating matters is the attempt to produce an ideal manufacturability and assembly design, which aids in repair and maintenance. Design iterations have become easier to perform and less time consuming due to newer technologies including computer-aided design (CAD), computer-aided manufacturing (CAM), and rapid prototyping (RP). This research began with a robotic gearbox that needed to have its design optimized for ease of manufacturing and assembly while maintaining a nice balance between speed and torque. The removal of the motor from the integrated motor-gearbox design was necessary to achieve the manufacturability and maintenance goals, as well as achieving size and weight goals. Multiple design iterations were made using I-DEAS, a CAD software package. The new gearbox was produced on a ThermoJet™ RP modeler, which provided another perspective for continued optimization.

 

Steam Pyrolysis & Hydro-Gasification of Biomass

Eden Haile

Mentor: Colin Hackett

University of California, Riverside

Carbonaceous waste materials, such as raw sewage and products of wastewater treatment, were converted to energetic gases using a combination of steam pyrolysis and hydro-gasification. The objective of this study was to produce gases with high calorific values such as CH4, CO, and C2-C3 hydrocarbon gases, while minimizing production of CO2. This was accomplished using a batch micro-reactor system. The reactor containing the waste material was heated by immersion in a molten salt bath maintained at a selected temperature. The reactor effluent was then measured using a Residual Gas Analyzer (RGA), which provided continuous measurements of the resulting gas species and their partial pressures. The system’s temperature (600 C to 700 C), water-to-carbon mole ratio, and peak reactant gas pressure (6-21 atm) were varied independently to learn how the reactions were affected. The recorded data indicated that as reactor temperature was increased, the total carbon converted from biomass to product gases increased. In addition, as the peak pressure of the gas reactant was increased, the total carbon conversion increased. Also, as the water to carbon mole ratio was increased, the production of energetic gases and CO2 increased. Using the continuous record of chemical speciation measurements from the RGA, reaction kinetics, rate constants, and activation energies were calculated. The highest calorific value of the product gases was measured at 82% of the calorific value of the biomass feed. The steam pyrolysis and hydro-gasification of sewage biomass has been shown to be a feasible technology for the disposal of these waste materials and their conversion to useful fuels.

 

Do MaxiK Channels, c-Src, and caveolin-1 Form a Macromolecular Complex in Vascular Smooth Muscle of Aorta?

Seunggu Han

Mentor: Ligia Toro

University of California, Los Angeles

Vascular smooth muscle cells (VSMC) control blood vessel diameter by their ability to contract and relax. The activity of VSMC is under the control of various bioactive agents, such as peptides and neurotransmitters. These agonists activate multiple cellular signaling pathways that, in turn, control vasoconstriction or vasorelaxation. Recent studies in Dr. Ligia Toro’s lab have described that several vasoconstrictors use MaxiK channels and c-Src tyrosine kinase, two abundant proteins in VSMC. In this project, I hypothesized that MaxiK and c-Src coassemble in specialized areas of the smooth muscle plasma membrane, known as caveolae, whose marker protein is caveolin. In preliminary data collection, I was able to detect MaxiK, c-Src, and caveolin-1 in aortic tissues using Western blots, specific antibodies, and infrared fluorescence. Bands at the expected sizes were labeled, ~130 kDa (MaxiK), ~65 kDa (c-Src), ~25 kDa (caveolin-1). Also, I was able to successfully express MaxiK channels and c-Src tyrosine kinase in HEK 293T for protein-protein interaction studies. My immediate goals are to determine if MaxiK, c-Src, and caveolin-1 co-assemble in VSMC and if MaxiK channels physically interact with caveolin and c-Src. Co-immunoprecipitation, immunoblotting, and molecular approaches will be used. I will also examine c-Src and caveolin interaction with MaxiK using MaxiK wild-type and MaxiK without c-Src and caveolin-binding motifs. The results show that antibodies can readily recognize the three proteins in a specific manner, and that sufficient amount of proteins can be recovered for protein-protein interaction studies.

 

Determination of Activation Energy of Transitional Metal EDTA Complexes

Steven Han

Mentor: Yong Ba

California State University, Los Angeles

In previous experiments, analyzation of the behavior of metal-EDTA complexes has been thoroughly investigated by VT-NMR and simulation. Depending on the type of metal binding to EDTA to form the metal-EDTA complex, different splitting patterns arise. The results showed that depending on the Z/r2 of the metal cation, an AB pattern could be formed at room temperature if the ratio was small. On the other hand, if the ratio was large, most likely a single line will arise from the complex. This research investigated into more detail the three metals of EDTA complexes, scandium, yttrium, and lanthanum. We examined these complexes to see if any trends arose from using both VT-NMR and simulation methods. In analysis, with both experimental and simulated spectra, linear correlation of all three metals arose and physical characteristics can be summarized from these results, in particular, radii, ionization energy, and electronegativity of the metal cations.

 

Development of a Generalized Transductional System for the Bacterial Predator, Bdellovibrio bacteriovorus

Renee Hanlin

Mentor: Mark Martin

Occidental College

Bdellovibrio bacteriovorus is a relatively uncharacterized bacterial predator of other Gram negative bacteria. Because there are few genetic tools available to analyze this interesting but "undomesticated" microbe, we have begun to develop a bacteriophage-driven system to move genes between different strains of Bdellovibrio by generalized transduction. Phage Mombo was originally isolated by Bentley Fane of the University of Arizona. We have demonstrated that this Bdellovibrio specific bacteriophage can move genetic markers between various host independent strains of this microbe, and even from host independent to wild-type strains. We are currently working toward optimizing this process, and believe that phage Mombo will be a useful tool for the genetic analysis of predation in Bdellovibrio.

 

Globalization and the Treaty Power of the United States

Patrick Hardy

Mentor: Ronald Steiner

Chapman University

In the early 21st century, globalization’s momentum is having particular and unexamined effects on federal systems. The most visible of these have come through the creation and implementation of treaties to enforce the "law of nations," to ensure rule of law for nations that engage in it. This paper argues, in the context of globalization, current legal interpretations of the power to finalize treaties are a threat to the U.S. Constitution’s 10th Amendment definition of federalism. Part I examines the enlargement of globalization’s impact on citizenry in the 21st century and the potential for even greater scope in years ahead. It assesses the impact that globalization has had on the volume, negotiation, and content of treaties. It concludes by observing that subjects previously considered domestic are now distinctly multi-national. Part II highlights the position of treaties in U.S. and international law. It reviews case law that suggests that any constraint on the negotiation or impact of domestic law can be nullified by a treaty. By analyzing the approach that courts have taken on the supremacy of treaties, this paper concludes that treaties will further impinge on domestic law. Given this increasing encroachment, the principle of a limited central government promised by the U.S. federal system of unified but sovereign states guaranteed by the 10th Amendment is simply a technicality to be sidestepped whenever it presents itself as an obstacle to the federal government’s accommodation to globalization.

 

Effects of Histone Acetylation on Glucocorticoid-Evoked Apoptosis

Elon Hartman

Mentor: Rheem Medh

California State University, Northridge

Apoptotic cell death is marked by changes in gene expression that lead to organized cellular suicide. In lymphoid cell lines, glucocorticoid (GC)-evoked apoptosis is associated with downregulation of c-Myc and cyclin D3, both of which regulate the G1-to-S transition. The acetylation state of histones is important to gene regulation, and histone hyperacetylation normally causes increased levels of gene expression. The effects of inhibiting histone deacetylation on GC-evoked apoptosis were tested in human leukemic T cells by co-treating cultures with dexamethasone (Dex), a synthetic glucocorticoid, and trichostatin A (TSA), a histone deacetylase inhibitor. Western blots were carried out to identify changes in gene expression, and cell growth rates were measured to determine whether TSA would cause a decrease in sensitivity to glucocorticoids. Results of the Western blots showed that, in cells treated with both Dex and TSA, increased c-Myc levels were present relative to cells treated with Dex alone. In contrast, cyclin D3 expression was notably reduced in co-treated cells compared to those treated only with Dex. Low-concentration treatments with TSA alone showed no large differences in either c-Myc or cyclin D3 expression compared to the untreated control. In preliminary studies, low concentrations of TSA did not significantly alter cell growth rate or GC-evoked cell death. These results indicate that changes in acetylation are important for GC-associated reductions in c-Myc expression and that such changes may be involved in the GC-evoked apoptotic response. Histone deacetylase inhibition appears to have a secondary effect on cyclin D3 expression that must be pursued further.

 

Reforming Urban High Schools

Ali Hasan

Mentors: Mary Christianakis & Norm Olson

Occidental College

The focus of this research is to address the question of how can we reform high school pedagogy to empower students. Currently, the No Child Left Behind Act has established test score standards that are well beyond the current performances of most inner-city high school students. This act depends upon a behaviorist teaching method and pedagogy that encourages teachers to teach their students through individualistic approaches, that reduce classroom interaction and socialization. According to education scholars, such as Lisa Delpit, James Ogbu, and Gloria Ladson-Billings, it is important that policies be written that will promote interactive teaching methods and pedagogy that can empower students. Ogbu’s thesis, in particular, is based upon the idea that many inner-city minorities feel that they are involuntary minorities of America and that such a feeling causes them to distrust the American educational system. Ogbu feels that the most effective way to gain the trust of all inner-city students is to empower them, by giving them more freedom, choices, and acceptance—ideals that only interactive teaching methods could deliver, not behaviorist ones. Through qualitative ethnographic observation, including interviews with teachers, students, and experts of an inner-city high school of high minority concentrations situated within an area of high poverty, in combination with the studies of educational theories behind pedagogy, this study shows that interactive teaching methods empower students, creating healthier learning environments for all types of learners, regardless of race or socio-economic status, and most important to some legislators, higher test scores. Ultimately, legislators ought to realize that the true solutions to reforming the public education system do not lie solely within policies of increasing budgets, introducing new standardized tests, or increasing score standards, but rather, within addressing the pedagogy that is used inside the classroom itself.

 

Expression of Gossypol Biosynthetic Enzymes in E. coli

Joy Marie Helou, University of La Verne

Mentor: Donald Pettigrew, Texas A&M University

The goal of this experiment was to construct a new vector to allow expression of the enzyme d-cadinene synthase from cotton (DCS) in the DH5a strain of Escherichia coli. It is well known that DCS catalyzes synthesis of the sesquiterpene d-cadinene, which is the first committed intermediate in gossypol synthesis in cotton. Gossypol is an important component of plant defense against pathogens and insects. The DCS cDNA from plasmid pcdn1-C1 was amplified by using PCR with primers designed to generate restriction endonuclease sites, which allow ligation of the coding segment for DCS into a new expression vector, pTrc99A. To move the amplified DNA insert into the new vector, both were cleaved with EcoR1 and Xba1, and the fragments were joined by using T4 DNA ligase. The ligation reaction product was introduced into strain DH5a via transformation of cells made competent by calcium chloride, and transformants were selected by ampicillin resistance. Recombinants were screened for by (1) using restriction endonuclease digestion of purified plasmid DNA and agarose gel electrophoresis to detect the insert DNA, (2) SDS-PAGE on total cell extracts to detect DCS synthesis, and (3) gas chromatography of ethyl acetate extracts of the cultures to detect enzymatic synthesis of d-cadinene. The control plasmid pGEX CA1C-26 was observed to contain an insert of the DCS cDNA. However, the DNA insert was not found in the pTrc99A constructs, and the cell extracts did not contain DCS protein or synthesize detectable levels of d-cadinene.

 

Influence of Discharge and Location on Debris Pile Volume and Composition

Aaron Hopkins

Mentors: Darren Stoub & Cheryl Swift

Whittier College

Natural rivers have the ability to trap debris floating downstream where it accumulates essentially forming a dam, channel bar, or new bank. These debris piles slow current velocity reducing the water’s capacity to transport sediment and nutrients so that even more sediment is deposited in the debris pile. We conducted a study on the East and West Forks of the San Gabriel River in July and August of 2003 in order to determine the effect of stream discharge, and location of the debris pile in the streambed cross section on the size and composition of debris piles. Debris pile volume was related to discharge as well as location in the streambed cross section. Reaches with higher stream discharge showed greater debris pile volumes on the floodplain, but lower volumes in piles on the bank and in the stream. The number of stems and the size of stems growing in debris piles were correlated with increased debris pile volume. Increasing numbers of stems can increase the sediment trapping function of debris piles as well as anchor the debris pile. These results suggest that increased amounts of sediment can be trapped on floodplains during periods of increased stream discharge.

 

Global Optimization for Molecular Systems

Gene Hsiao

Mentor: Gary Huber

University of California, San Diego

Understanding the structure of proteins is a crucial step toward new drug development, preventative treatment, and improved care for those already afflicted with disease. Unfortunately, according to the Levinthal Paradox, it would take longer than the age of the universe to discover the correct folding state through brute-force computational means; nature can solve this NP-complete problem and correctly fold a protein in less than a minute. Simulated annealing may be a more efficient approach for reaching the correct folding state. This research investigates the effectiveness of several different simulated annealing approaches for finding the global minimum of complicated energy functions that may describe proteins. We employ molecular dynamics, a Monte Carlo Markov Chain heuristic, a hybrid of the aforementioned, and finally the weighted-ensemble simulated annealing method. These methods are applied to the Lennard-Jones function, which, despite having a trivial minimum for a single pair of neutral atoms, becomes a complex energy landscape across a larger number of particles when many of these curves are superimposed. Furthermore, energy minimization of atomic clusters has very practical importance for physical scientists, particularly in the case of protein structure prediction.

 

Investigating a Novel Lifespan Gene in Drosophila melanogaster

Richard Hsu

Mentor: Brian Zid

California Institute of Technology

Aging is a universal process among living organisms in which homeostasis decreases and chance of death increases with age. Trying to understand aging in a simpler organism, such as Drosophila, is a possible intermediate step in understanding aging in humans. A screen for lifespan extension was performed using a driver line and a collection of EP lines. A driver line has a P-element that expresses the yeast transcriptional activator, gal4, while an EP line has a complimentary P-element that contains the DNA binding sequence of gal4. When a driver is crossed to an EP, the region downstream of the EP will be overexpressed. The mutant EP3306 was identified and found to have a reproducible lifespan extension. The EP3306 insertion site was found, and the putative gene overexpressed appeared to be an uncharacterized gene, CG7900. A genomic transgenic was constructed to verify that overexpression of CG7900 extends lifespan in an independent line. A recombinant was made between EP3306 and the daughterless-gal4 driver to look at interactions with other long-lived lines in the lab. Results show that CG7900 is the cause of increased lifespan and the gene itself seems to play a vital role in metabolism. In conclusion, the EP is located 300 base pairs upstream of the CG7900 gene, which has a high sequence similarity to a human protein. Hence, the understanding of how overexpression of CG7900 extends lifespan could be important to not only the understanding of fly aging, but also the aging process in humans.

 

The Distribution and Binding Partners of the Motor Protein Kinesin II in Resting and Carbachol Stimulated Lacrimal Acini

Jasmin Hu

Mentor: Sarah Hamm-Alvarez

University of Southern California

Kinesin II is a member of the kinesins, one of two families of microtubule-based motor proteins, the other being the cytoplasmic dyneins. It is a plus-end director of the movement and transport of organelles in the cell, particularly secretory cells. Previous studies on melanophore transport in Xenopus melanocytes suggest that kinesin II interacts and requires the dynactin complex, a cofactor of cytoplasmic dynein, in transport activity. I decided to address if that would be true in lacrimal acini, secretory epithelial cells responsible for production and release of tear proteins. Further, I explored whether secretagogue stimulation, which stimulates exocytosis that utilizes cytoplasmic dynein and dynactin, would cause changes in the interaction of kinesin II and dynactin. I used immunofluorescence staining to determine the distribution of kinesin II and its association with the p150Glued subunit of dynactin. I found that kinesin II and p150Glued strongly co-localized after stimulation, showing that kinesin II and dynactin interact at secretion sites. To further test this, I used co-immunoprecipitation, and found that after stimulation, antibodies against kinesin II pulled out p150Glued, and in the reverse experiment, antibodies to p150Glued pulled out kinesin II. This led to the question whether kinesin II would be associated with dynein, since both utilize dynactin in their functions. Further immunoprecipitation revealed that kinesin II also pulled down the intermediate chain of dynein. These results indicate that kinesin II and dynactin interact in lacrimal acini, and dynactin bind to dynein and kinesin II simultaneously.

 

Exposure of the Hyperthermophilic Anaerobe Pyrococcus furiosus to Oxygen

Charles Hummel

Mentor: E.J. Crane

Pomona College

Pyrococcus furiosus is a hyperthermophilic archaeon found in hydrothermal vents. These strict anaerobes require a strongly reducing environment in order to grow. Extensive preliminary studies were undertaken in order to determine the proper growth conditions for Pyrococcus prior to exposing it to stress conditions. It was determined that despite their anaerobic nature, it is necessary to shake liquid cultures of Pyrococcus, especially during growth with insoluble elemental sulfur. This greatly reduces both the variability and length of the lag phase of growth. Previous studies have shown that Pyrococcus is able to survive exposure to oxygen at lower temperatures. We are interested in whether this survival is due to the organism actively removing oxygen from its environment, or whether the organism is simply protected by decreased rates of oxidation of cellular components at lower temperatures. Pyrococcus cells at a defined temperature are exposed to oxygen, and oxygen consumption is measured using a heat-stable oxygen electrode, which can be inserted through a septum into the sealed media bottle. Through these results, we hope to determine whether the survival of Pyrococcus cells exposed to oxygen at lower temperatures is due to the action of an oxidative stress response system or whether it is due to reduced susceptibility of Pyrococcus in oxygen at lower temperatures.

 

VEGF-mediated Response to Acute Cerebral Ischemia

Andrew Hurder

Mentors: Dave Bourgaize & Cheryl Swift

Whittier College

Following an acute ischemic stroke, hypoxia occurs in nearby cerebral tissue. Hypoxia induces the expression of vascular endothelial growth factor (VEGF), which in turn increases vascular permeability and edema in the brain, leading to tissue damage. This study is aimed at understanding how endothelial cell-signaling pathways facilitate this response, specifically to identify the role of focal adhesion kinase (FAK) in the VEGF-induced physiological response to acute ischemic stroke. FAK mutants have dramatically reduced volumes of damaged tissue following a stroke. FAK phosphorylates through several integrins and kinases in this cell-signaling pathway, such as Src and Erk1/2. My study is localized on the signaling of FAK expression through endothelial cell barriers within murine and cell culture models. My data shows that FAK is expressed through growth factors in mouse embryonic fibroblast cells, visualized in SDS-PAGE experiments.

 

JnK: A Genetic Framework for Distributed Discovery Mechanisms

Khanh Huynh

Mentors: Tatsuya Suda & Junichi Suzuki

University of California, Irvine

In today’s technology, peer-to-peer (P2P) systems offer a simple and efficient way to store and access large amounts of data. P2P is a type of network that takes advantage of distributed resources available by sharing. The explosive growth of P2P applications in recent years is due to the fact that these systems provide low cost, high availability of large number of computing and storage resources, and high network connectivity. Many existing P2P protocols have different capabilities, transportation, and needs

 

thataasfdsthat required by a variety of network applications. Due to the different needs of network objects, an extensive survey was conducted to develop a generic framework to improve the chances of locating and storing network resources. Selectively, P2P systems, such as Gnutella, Freenet, Chord, NeuroGrid, and Tapestry, and genetic frameworks, such as Microsoft .Net, Unified Peer-to-Peer Database, JXTA, Structured Peer-to-Peer Overlays, and Anthill, were chosen to identify common and genetic interfaces and data structures. Well-known lookup mechanisms, such as Distributed Hash Tables (DHT), Decentralized Object Location and Routing (DOLR), and Group Anycast and Multicast (CAST), that provide a foundation to develop a genetic framework are carefully analyzed. As a result of the survey, I implemented a new P2P protocol called GnutellaUNI that provides a more complicated and enhanced search criteria called compound-search. My stimulation of genetic framework called JnK implemented Gnutella, Freenet, NeuroGrid, and GnutellaUNI protocols. The implementation of the JnK framework is written in JAVA and CORBA as a middleware to develop and deploy distributed applications

 

The Oxidation of L- and D-Dopa by Synthetic Mimics of Metal-ion Containing Enzymes, such as Tyrosinase and Alkaline Phosphatase

Robert Iafe

Mentor: James Roe

Loyola Marymount University

The interest in enzymes is due to several factors: their dynamic and essential role in the cell, their extraordinary catalytic power, and their selectivity. In this experiment, two characteristics will be evaluated: enzyme activity as a function of structure and molecular selectivity. I propose to determine whether the copper and zinc ion derivatives of tris[2-(3,5-dimethyl-1-pyrazoyl)methyl] amine and that of tris[2-(3,5-dimethyl-1-pyrazoyl)ethyl] amine serve as reasonable models of the active sites of metalloproteins, such as tyrosinase, which contains copper, and alkaline phosphatase, which contains zinc. The activity of the mimics to catalyze the oxidation of L- and D- dopa (3,4-dihydroxyphenylalanine; a precursor to the neurotransmitter, dopamine) in aqueous solution will be compared with that of the native enzymes. It has been shown that the copper complex of TPM successfully mimics the reactivity of the enzyme tyrosinase in the catalysis of the oxidation of catechol in methanol solution (Malachowski et al., 1992). It was speculated in this article that the difference in reactivity between the two complexes depends on the differences in geometry. Another speculation is that the TPE complex completely surrounds the copper ion and due to steric hindrance the substrate is unable to approach the metal ion directly in order to be oxidized. In addition to monitoring the activity due to the different geometries of the model compounds, different metal ions will be substituted in order to determine which serves as the most effective catalysts. By experimental analysis of changes in geometry and metal ion substitution on the oxidation of dopa, insights should be gained on the mechanism of tyrosinase.

 

In Situ Hybridization of Melk in Embryonic, Newborn, and Adult Mice Brains

Sylvie Inkindi

Mentor: Harley Kornblum

University of California, Los Angeles

Maternal embryonic leucine zipper kinase (Melk) is a gene in the Snf1/AMPK serine/threonine kinase family. Members of this family contribute to cell survival in response to nutrition starvation. Melk has a leucine-zipper motif within the N-terminal catalytic domain. This motif allows for protein-DNA and potentially protein-protein interactions (Seong et al., 2002). Melk is differentially expressed during mouse embryogenesis. In germ cells, an intense signal is detected in mitotically active stem cells called spermatogonia (Heyer et al., 1999). This suggests that Melk is expressed in highly proliferating cells. The identity of the Melk gene as a neural progenitor gene was assessed using microarrys comparing neural stem/progenitor cells against differentiated cells derived from a representational difference analysis (RDA) subtraction. In situ hybridization demonstrated that Melk is expressed in the germinal zones of the developing mouse brain. This is consistent with Melk playing a specific role in neural progenitor or stem cells (Geschwind et al., 2001; Easterday et al., submitted). The present study focuses on the expression of Melk in whole brain sections of embryonic, newborn, and adult mice using in situ hybridization.

 

Taming the Elusive 310-helix: Synthesis and Conformational Analysis of Olefinic Heptapeptides

Wendy Iskenderian

Mentor: Daniel O’Leary

Pomona College

Although not as widely recognized as the a-helix, the 310-helix is becoming increasingly recognized as an important structural motif in smaller, hydrophobic and biologically active peptides. Previous NMR studies from these laboratories have shown that 310-helix stabilization can be achieved in heptapeptide model compounds (modeled after Karle’s peptide) using serine allyl ether-derived RCM crosslinks connecting the i,i+4 amino acid side chains. We have demonstrated that the ring-closing metathesis reaction can be used to install a chemical crosslink between the i,i+3 serine side chains in a related heptapeptide. Current research is focusing on the synthesis and conformational analysis of the related homoserine heptapeptide. Computational studies suggest that the size of the RCM-derived macrocycle (as determined by the use of serine vs. homoserine allyl ether) can profoundly influence the preferred helix type in the i,i+3 tethered heptapeptide. It is expected that both the i, i+3 tethered serine and i, i+3 tethered homoserine cyclic heptapeptides will form stable 310-helices in the solution phase, which will be investigated by circular dichroism studies this winter (which we will perform at the University of Wisconsin). Additionally, NMR temperature dependence studies are being performed to compare the solvation of the amides in both the cyclic and the acyclic serine heptapeptides.

 

Reaction of 2-Alkyl-3-Bromo-1,4 Naphthoquinone with Amines; A Novel Demethylation Reaction

Cameron Iverson

Mentor: Tetsuo Otsuki

Occidental College

Derivatives of 1,4-naphthoquinone are utilized as anti-fungal, antibacterial, and potential anticancer pharmaceuticals, which often show unexpected reactivities. Here we study the reactivity of 2-bromo-3-methyl-1,4-naphthoquinone toward primary and secondary amines. In the reaction with primary amines in methanol, contrary to our expectations, demethylation of 2-bromo-3-methyl-1,4-naphthoquinone generates 2-alkylamino-3-bromo-1,4-naphthoquinone as the major product. Furthermore, secondary amines such as N-ethylmethylamine gave 2-methylamino-3-bromo-1,4-naphthoquinone, presumably as the secondary reaction product. Unexpectedly, the reaction of 2-bromo-3-ethyl-1,4-naphthoquinone with primary, secondary, and tertiary amines yields very different results. In the reaction 2-bromo-3-ethyl-1,4-naphthoquinone with propylamine, for example, substitution occurs for the bromine. We believe this is due to the varying acidity between the two 2-alkyl-3-bromo-1,4-naphthoquinones. The scope and limitations of the reaction and reaction mechanism are studied.

 

Functional Enzyme Microarrays

Aaron Jacobs, Harvey Mudd College

Mentor: Angelika Niemz, Keck Graduate Institute

Biochemical activities for gene products of newly sequenced genomes are generally obtained via functional annotation based on sequence homology to known proteins, an approach that is often incomplete and at times misguiding. To analyze entire proteomes, a high throughput method must be available to determine functionality of each expressed protein. Due to the fragile nature of proteins, most assays are performed in a homogeneous format using microtiter well plates, which limits the miniaturization possibilities. By immobilizing the protein in micron-scale surface bound hydrogel pads, a protein microchip can be developed, leading to drastically increased integration density. During this project, we optimized techniques for obtaining reproducible microarrays as a function of several variables. Then we developed an alternate procedure for modifying proteins with acrylamide functional groups, which enables copolymerization of the proteins into the hydrogel matrix. Multiple assays using the fluorogenic substrates Amplex Red and Quanta Blu were employed in an attempt to analyze the activity and kinetics of Horseradish Peroxidase microarrays. To develop a practically useful screening system, functional protein microarrays were fabricated through a combination of affinity capture and copolymerization. This method is applicable to protein A fusion proteins, relying on the Fc fragment’s affinity for protein A. Fc fragments were acrylamide modified and immobilized in the hydrogel matrix, which provides an affinity support for future enzyme microarray studies.

 

Expression of Markers of Microglial Activation in Alzheimer Disease (AD) in Relation to Severity of Cerebral Amyloid Angiopathy (CAA)

Syed Jaffery

Mentor: Harry Vinters

University of California, Los Angeles

Tissue microarray (TMA) is a procedure by which autopsied brain tissues from similar regions of multiple cases can be studied on one slide. A TMA was created from Alzheimer Disease (AD) patients having severe cerebral amyloid angiopathy (SCAA) vs. minimal cerebral amyloid angiopathy (MCAA). A TMA, including samples of cortical and subcortical regions from the brains of 29 autopsied AD patients, was analyzed. The TMA was stained with an antibody directed against MHC-II, an indicator of microglial activation. We hypothesize that there are differences in microglial number and/or distribution, which may result from differing degrees of CAA in the two groups of AD (SCAA and MCAA). Microglial counts were performed using the Olympus BX-40 compound microscope at 400 magnification. The cell counts of immunoreactive microglia were correlated with the degree of CAA. The data obtained was analyzed using student’s t-test. The t-test showed no statistically significant difference in microglial MHC-II expression between the two groups examined. The subcortical region contained significantly greater numbers of immunoreactive microglia in each group (SCAA p = 0.0242 and MCAA p = 0.0396). Further studies are planned using lymphocyte function associated antibody-1 (LFA-1) as well as markers of glial proliferation.

 

Processing and Characterizing Bulk Metallic Glasses (BMGs) and BMG Composites

Tracy Janov

Mentor: Ersan Ustundag

California Institute of Technology

Bulk Metallic Glasses (BMGs) are metal alloys that are stronger than steel and also are fracture-resistant and highly ductile because of their high elastic strain limit. Their potential uses range from golf clubs to cell phone casings to aircraft frame components. To develop BMGs, a sample is produced in a vacuum chamber and cooled very rapidly. Then x-ray diffraction analysis identifies its phase, a detailed microscopic study reveals how the dendrites form inside the glass matrix, and tensile and compression trials test its strength. It is important to understand how the shear bands that form in the matrix interact with their metallic reinforcements at the microstructural scale so that we can understand why certain composite mixtures have more desirable properties than others. Although BMG samples are limited to being small so that their cooling rate is high enough, they are easily produced and represent a breakthrough material that is already being used in various industries.

 

Rootless Matrices

Camden Jansen

Mentor: Scott Annin

California State University, Fullerton

Given a square matrix, we ask: Does it have a square root? If the matrix is diagonalizable, you may know that the answer is always "yes." But what about in general? And what about cubed roots, such as 4th roots, 5th roots, and so on? This project describes my research on the classification of rootless matrices. A rootless matrix is a square matrix that fails to have a square root, cubed root, 4th root, and so on. This work generalizes results published by B. Yood in Mathematics Magazine (June 2002) by using the machinery of Jordan Canonical Forms. After reviewing this important tool, I will use it to present the solution to the classification problem described above. That is, we describe precisely which square matrices possess roots. The results may surprise you, and they lead to a host of other intriguing questions as well.

 

Power Structures and Empire

Doug Jensen

Mentor: Nikhil Singh

University of Washington

Official discourse, particularly in matters of foreign policy, is saturated by politically expedient exhortations in the United States. While this may seem to be a relatively new phenomenon in the midst of what the Bush Administration calls the "War on Terror," the ideas presented by political officials, and the actions that result from these ideas are not spontaneous creations. Indeed, the current ideology of those in power has much in common with the ideals and logic of liberalism as it emerged in the 19th century. Hence, if we are to gain some kind of understanding of this present moment, it is necessary to view similar periods of international aggression in the past. The United States’ invasion of the Philippines is such an example. Upon examining a wide variety of sources including news accounts from the period, speeches made by political figures, letters to the editor, and personal accounts, three methods of control and dominance that lie within the "language of freedom" emerge. First, factual events were deliberately misrepresented by authorities. Secondly, assumptions not subject to the burden of proof were widely espoused. Finally, the logic of officials such as Theodore Roosevelt or John Hay centered on extremely authoritarian conceptions of "freedom." The results of these methods in practice make it immediately clear that if peoples of the world are to ever discover what democracy or freedom mean, then the actions of the powerful have extremely little to offer them in their search.

 

Optical Sensor for Non-Invasive Detection of Oral Cancer

Goldwyn Jequinto, University of California, Irvine

Mentor: Petra Wilder-Smith, University of California, Irvine & Loma Linda University

Using existing techniques, non-invasive diagnosis or monitoring of oral pathologies is not possible. The object of this investigation is to identify in vivo fluorescence excitation/emission spectral characteristics of healthy and pathological oral tissues using a non-invasive fiber-optic diagnosis system. In patients referred to UCI Medical Center Department of Otolaryngology and/or UCI Cancer Center for inspection of existing leukoplakias and erythroplakias, in vivo multi-wavelength excitation/detection spectra from normal and pathological sites were acquired using a flexible fiber-optic system prior to conventional biopsy. Spectral characteristics of dysplastic, malignant, and other pathological sites were identified and characterized. Detailed diagnostic status of each lesion mapped was obtained from histopathological sections of the biopsy tissues. Considerable differences were consistently observed between spectral emissions of the different pathologies investigated, based mainly on changes in tissue extracellular matrix, vasculature, and tissue metabolic state. Characteristic in vivo spectral signatures were identified for a wide range of oral histopathological diagnoses.

 

Sex Differences in Mating Preferences for Humor

Jennifer Joeyen-Waldorf

Mentor: David Rakison

Carnegie Mellon University

Evolutionary psychology makes predictions about human behavior based on what behaviors would have been adaptive in the environment of evolutionary adaptation (EEA). The aim of these studies was to examine sense of humor in the context of evolutionary psychology. Buss found that sense of humor in potential mates was highly and equally important to males and females (1988). We have recently determined, by examining online personal advertisements (n = 2,640), that in a mating context, females seek out males with an "active" sense of humor (saying or doing something funny), while males seek out females with a "responsive" sense of humor (laughing at or appreciating something funny). We identified this effect in countries in Europe, North America, South America, Africa, and Asia. We have also used self-report to examine the possibility that "active" and "responsive" senses of humor are predictors of other traits already known to be valued by females or males in a mating situation (for example, fidelity, dominance, or generosity), which may have caused selective pressure for these mating preferences during human evolution.

 

Constructing Social Difference in the Everyday Lives of Children

Nastassia Isis Johnson

Mentor: Marjorie Goodwin

University of California, Los Angeles

 

The reality of everyday life in the United States is laden with discrimination based on differences ranging from ethnicity, socioeconomic status, physical features, and disability. Likewise, knowledge of these social differences greatly influence the thoughts and actions through which people construct their everyday lives and such notions of difference are readily available to children simply through the direct observation of the world around them. However, it has been held that young children are incapable of critically understanding the implications of ethnic or class matter. Through my research I investigate when, where, and how children as young as four understand concepts of social difference. Moreover, my research has focused on the relationship between this knowledge and the tendency to use this information in the construction of meaning, expression, and conduct in children’s own social milieu. Through naturalistic observations of two groups of 20 four-year-old children at a school environment and daycare setting, I have found that children are aware of concepts about difference through the behaviors and verbal discourse demonstrated. I suggest that ideas of difference, such as ethnicity, correlate with ideas about social class differences and both are used by children in their peer interactions. Through analysis of the data (extensive field notes) of my observations, I have assessed that children’s behaviors and expressed beliefs differed based on location and were heavily influenced by teacher/adult expressed beliefs and behaviors and their involvement with the children during peer interaction. As a result, the construction of social difference by children is important because such behavior is not only harmful to its target, but over time this behavior contributes to the continuation of discrimination and victimization.

 

Competence of Escherichia coli in the Transformation of Plasmid PBR322

Kelly Kawashiri

Mentor: Steven Goodman

University of Southern California

Escherrichia coli (E. coli) is mainly found in the intestines of animal and humans. It is helpful in the aid of breaking down food. In my lab, this bacteria, however, is commonly used to make copies of plasmid DNA. E. coli does this is through transformation, which is the extracellular uptake of DNA. Although in previous research it was discovered that the range in competence varied with temperature. In my project I had to find the specific range of temperature in which the E.coli was most competent and then find out the reason for it’s competency. I first ran preparatory tests for the DNA plasmid PBR322. I had to be sure that I was growing the pure plasmid DNA before finding the E. coli’s competency. I isolated the DNA by using an antibiotic. Then I grew the E-coli and the DNA plasmid in different temperatures ranging from body temperature to 20 C.

 

Curcumin in Curry Powders: Quantitation by High Performance Liquid Chromatography

Fatima Khwaja

Mentor: Cheryl Rock

University of California, San Diego

Curcumin, derived from the rhizome, Curcuma longa L., is one of the principal ingredients in turmeric and curry powders used as a spice in Asian Indian cuisine. More recently, laboratory and clinical research has shown that curcumin has the potential to contribute to the prevention of cancer and other chronic diseases. Specifically, studies have demonstrated that dietary curcumin significantly inhibits colon tumorgenesis and tumor size in animal models. While the manufacturers of the various spices and curry powders list the ingredients in a relatively quantitative manner, they do not give exact amounts. In order to determine and compare the quantitative amounts of the curcumin that is present in various curry powders, a high performance liquid chromatography (HPLC) technique was used. It was found that pure turmeric had the highest curcumin concentration, averaging 1.25% curcumin. The curry powder samples, with one exception, had large differences in curcumin content and relatively small amounts present. Considering bioavailability of the compound, these differences could possibly have significance in terms of its influence in chemoprevention.

 

Rational Polygons: Construction and Properties

Radoslav Kirov

Mentor: Ramin Naimi

Occidental College

The majority of geometric constructions do not produce rational "parts." For example a triangle with rational sides seldom has rational area. This research was on the existence of so-called rational polygons, namely polygons with rational sides, diagonals, and area. We found a construction method for producing rational polygons with an arbitrary number of sides. Moreover we proved certain properties of those polygons. For any rational polygon, all segments of the lines formed by extending the sides and diagonals are rational and so are all areas bounded by those lines.

 

Dendritic Growth Cones and Recurrent Basal Dendrites are Typical Features of Newly Generated Dentate Granule Cells in the Adult Hippocampus

Matthew Korn

Mentor: Charles Ribak

University of California, Irvine

Granule cells in the hippocampal dentate gyrus are generated throughout the adult life of mammals, and recent studies indicate that they are incorporated into neural circuitry and mature into functional neurons. To determine whether newly generated granule cells form dendritic growth cones during this process of synaptogenesis, we used the immunocytochemical method to label within these neurons doublecortin, a protein associated with microtubules found in neuronal growth cones of newly generated granule cells. Here we show that both dendritic growth cones and recurrent basal dendrites are common features of newly generated dentate granule cells. As previously described, these cells appeared along the hilar border of the granule cell layer as well as in the subgranular zone of the dentate gyrus. These observations for growth cones suggest that dendrites of newborn neurons in the adult nervous system grow in a similar way as those found in the immature brain. This study is significant because it is the first to show dendritic growth cones in the dentate gyrus of the adult nervous system.

 

Zinc Oxide Growth as Thin Film Transducer

Haroon Lais

Mentor: William Tang

University of California, Irvine

The high quality of the zinc oxide piezoelectric thin film transducer is used on the micro-scale resonator application. Using the radio frequency (RF) sputtering technique, there are several parameters including pressure, temperature, Ar/O2 ratio, and RF power that will influence the quality of the thin film. These parameters will determine the crystal orientation, grain size, surface roughness, and the deposition rate of the piezoelectric thin film. To characterize the thin film, scanning electron microscopy (SEM) is used to investigate the grain size, surface roughness and the cross-section of the crystal orientation. X-ray diffraction technique will also be used to determine its crystal orientation.

 

Microarray Analysis of Longevity in Drosophila melanogaster Mutants

Anna Lam

Mentor: Horng-Dar Wang

California Institute of Technology

Aging is the biological process of deterioration. A prominent factor for the span of longevity in organisms is their physiological ability to resist different stresses. In previous studies, a forward genetic screening for multiple stress resistance has led to the discovery of several long-lived Drosophila mutants. Among them, 1101, 1130, and 2456 have been able to resist stresses of paraquat poisoning and starvation while having life spans up to 35% longer than the control w1118. The genetic factors of these three mutants’ longevity are not clear. The "reverse genetics" method is particularly useful in addressing this problem. Because all three mutants are long-lived, the genes co-regulated among them may provide a clue to the biological pathway of longevity. To narrow the genes for longevity, I used the relatively new Affymetrix GeneChip microarray technology to analyze the genome-wide expression of the 13,976 genes in the three mutants. Analysis of this data allows me to find genes that are either over or under-expressed in all three mutants compared to genes of the control. Investigation of the particular function of all these common genes may lead to the identification of the biological processes for longevity. Better understood, the candidate genes found from this analysis might prompt solutions to human aging in the future.

 

Detection of Small Molecular Weight Thiols in Pyrococcus furiosus

Kyle Lancaster

Mentor: Edward Crane

Pomona College

Oxygen, so necessary to terrestrial life, spells death for many deep-sea thermophilic microorganisms. Such organisms do, however, possess mechanisms to counter the ill-effects of oxidative stress. Genomic and biochemical data gathered for the hyperthermophile Pyrococcus furiosus suggests that one method of coping with oxidative stress is through the activity of the enzyme Coenzyme A disulfide reductase (CoADR), an enzyme that keeps the low-molecular weight thiol coenzyme A (CoA) in a form that can be used to reduce oxygen or other reactive oxygen species. The presence of this enzyme suggests the presence of high concentrations of CoA within Pyrococcus. However, as of now it is not known whether CoA is present at high levels within the cells or rather if the CoADR uses another thiol as its substrate. Using fluorescence labeling, we sought to determine what thiols were present within the cells. Pyrococcus cells were labeled with monobromobimane (MBBr), a reagent that produces fluorescent adducts upon reaction with thiols. Following extraction, the labeled thiols were separated chromatographically via HPLC and compared to standards. Cellular thiols present in disulfide linkages were also analyzed by assaying in the presence of dithiothreitol, a disulfide reducing agent. We found strong evidence for the presence of high concentrations of CoA in Pyrococcus.

 

Studies in the Purification and Structure Characterization of a Helical Heptapeptide

Erica Lanni

Mentor: Daniel O’Leary

Pomona College

The importance of helical peptides for applied chemistry and biochemistry has inspired much research into stabilizing and manipulating their structures. We have been exploring the properties of a family of such helical peptides for a number of years. Currently, research is focused on the tethered and non-tethered variations of the heptapeptide Boc-Val-Ser(O-Allyl)-Leu-Aib-Ser(O-Allyl)-Val-Leu-OMe. In this instance a tether can be formed using the Grubbs’ ruthenium olefin metathesis catalyst between the two O-allyl serine residues located in the i and i+3 positions. In this study, we report methods for purifying the acyclic heptapeptide and the cyclic isomers using high performance liquid chromatography. We also used NMR spectroscopy to study the degree of intramolecular hydrogen bonding within the peptide helices. Finally, we looked at differences in the cis/trans selectivity using two versions of the Grubbs’ catalyst, where we found the "second generation" Grubbs catalyst to be far more trans-selective when tethering the serine O-allyl functional groups.

 

An Analysis of Hamptonese Using Hidden Markov Models

Ethan Le

Mentor: Mark Stamp

San Jose State University

The mysterious writing system known as Hamptonese has baffled cryptologists for the past 40 years. Hamptonese was developed by James Hampton, a Washington, DC, janitor who also created an amazing work of visionary art entitled "The Throne of the Third Heaven of the Nations’ Millennium General Assembly." While the Hamptonese text clearly has some religious significance, nothing specific is known of its content or meaning. In our research, we analyzed Hamptonese using Hidden Markov Models (HMMs). HMMs provide probabilistic information about the underlying state of a model, given a set of observations of the system. In our model, the Hamptonese text is the set of observations and the underlying (and unknown) language is the hidden part of the HMM. This approach was used as a tool to help determine whether Hamptonese was composed as a simple substitution of English or any other known language. To this end, we also cross-referenced Hamptonese symbols with 232 languages. In addition, we examined Hamptonese in connection to its biblical references, writing patterns, and organizational patterns. Although our results did not decipher the text, we have clearly established that Hamptonese is not a simple substitution of characters for letters in English text. Furthermore, our analysis did not reveal any significant similarities to other languages. However, organizational patterns and biblical passages found in Hamptonese do suggest possible interpretations of the text. Our work has yielded the first substantive results in the analysis of Hamptonese and will prove valuable to future researchers studying this language.

 

Method of Constructing Distributed Parallel Threads Using Templates

Michael Le

Mentors: Lubomir Bic & Michael Dillencourt

University of California, Irvine

The process of generating distributed parallel code from sequential code is a complex task. Such conversion requires sequential code to be mapped into some form dependency graph. Any sequential code to dependency graph transformation requires the analysis of loops. Most loops from modern programs have lengths that are dynamic in nature. A static dependency graph representation of loops of variable length is unacceptable. We propose using meta-graphs, or templates, to represent these loops. Templates capture the overall dependency of a loop and not its actual dimensions, thus templates lead to a more natural representation of loops with variable lengths. Because dependencies of a loop are represented in these templates, it is possible to construct threads, specifically distributed parallel threads, for a loop without having to know the loop’s actual dimension. The method of constructing threads is made concrete by comparing the thread layout between two methods of loop representation, static dependency graphs and templates. It can be shown that the thread layout using templates accurately matches the thread from the static dependency graph with the important addition of being generalizable to a loop of variable length. It is expected that the template representation of loops and the method of constructing distributed parallel threads using templates will greatly assist in the future goal of automating the transformation of sequential to distributed parallel code.

 

The Evolution of Rhodopsin in Nymphalidae

Lawrence Lee

Mentor: Adriana Briscoe

University of California, Irvine

Rhodopsin is a G-protein coupled receptor in photoreceptor cells that is light sensitive. In butterflies, it is composed of an opsin protein covalently attached to the chromophore, 11-cis-3-hydroxyretinal. The chromophore alone absorbs light in the ultraviolet regions of the spectrum; however, certain amino acids in the chromophore binding pocket of the opsin protein can increase the peak absorbance (l max) of the visual pigment to the longer wavelength region. Furthermore, previous studies in butterflies have shown that amino acid changes in the opsin protein have led to red-shifted sensitivities (Briscoe 2001, 2002). This research studies the amino acid composition of the opsins in butterfly species with independently evolved red-shifted pigments to determine what evolutionary events have taken place that may be responsible for the physiological shift in sensitivity. We chose two species with red-shifted sensitivities, Danaus plexippus and Anartia jatrophae, and one species with the ancestral, green-sensitivity, Inachis io. For each of the species, I performed polymerase chain reactions (PCR) using two or more sets of primers and cloned the PCR products. After extracting the plasmids from selected clones with the DNA insert, I sequenced the plasmid DNAs. I obtained partial opsin gene sequences for all three species. These data were compared with previously published green- and red-sensitive pigments and examined for amino acid substitutions that are correlated with known spectral tuning sites in vertebrates and insects.

 

Studies of Critical Micelle Concentration Using Capillary Electrophoresis

Michael Lee

Mentor: Phoebe Dea

Occidental College

The formation of sodium dodecyl sulfate (SDS) and chlorpromazine hydrochloride (CPZ) micelles was studied using capillary electrophoresis. The elution time of a neutral marker was used to determine when the surfactant had changed from its monomer to micelle form. The marker’s interactions with the surfactant changed as the monomer formed micelles, and caused the marker’s elution time to change as well. The elution times of a range of surfactant concentrations were graphed, and from this data the critical micelle concentration (CMC) was determined. This method worked well for SDS using 2-naphthalenemethanol as the marker; the CMC was determined to be 3.4 millimolar. This method, however, did not work as well for CPZ because of CPZ’s absorbance of ultraviolet (UV) light. This character caused a poor baseline for the electropherogram and made finding a suitable marker difficult. Possible markers were tested using UV spectroscopy to determine if their absorbance was strong enough to be seen through CPZ’s absorbance. Preliminary tests with benzyl alcohol showed that it may be a usable marker

 

Research on Propulsion Mechanism of Underwater Gnats—Fishtels

Vinh Lee

Mentor: Marc Madou

University of California, Irvine

We are developing a small underwater self-propelled autonomous vehicle, which will use a mechanism similar to fish swimming, that could open up new applications, such as clandestine operations and surveillance. The propulsion part is essential to the whole device. Artificial muscle material could be used to make biomimetic fins to generate propelling forces. In order to determine the input power from the battery, the drag force of the vehicle needs to be estimated theoretically or numerically, and energy efficiency of the propulsion needs to be addressed. Optimal design factors such as shape of the body, number, and shape of the fins will give this fishtel faster speed and more efficient control.

 

3D Lithography

Young Lee

Mentor: Marc Madou

University of California, Irvine

Lithography is the use of light to create patterns on a surface. The light-sensitive medium used, called photoresist, changes solubility when exposed to light. During exposure, a mask selectively allows light to pass through, and the photoresist is developed to create the desired 2D patterns. With the advent of MEMS (Micro ElectroMechanical Systems), there has been an interest in creating micro or nanoscale 3D structures. Much of the fabrication of today’s MEMS devices is limited because the processes used are inherited from conventional integrated circuit technology, which is two-dimensional. For example, very small precision lenses cannot be created using standard lithography techniques because the curvature of the lens cannot be produced. I have experimented with the many parameters involved in conventional lithography to create 3D structures. For example, exposure and development time can be varied to change the vertical profile of the edges of the patterns. With a thick photoresist layer, truly 3D structures were created. I learned how to fabricate 3D microstructures by working in the clean room (Integrated Nanosystems Research Facility). Increasing exposure dose and adjusting development time allows fabrication of conical structures. Grey-Tone Masks with multiple levels of transparency can also be used to form multi-level structures.

 

Molecular Dynamics Simulation Studies of the Structure and Function of Mutant Surfactant Protein B Peptides

Jenny Lester

Mentor: Douglas Tobias

University of California, Irvine

Lung Surfactant is a mixture of phospholipids and apoproteins that line the surface of the alveoli and maintains respiratory stabilization during the breathing process. Deficiency or dysfunction of lung surfactant has resulted in respiratory diseases, particularly Neonatal Respiratory Distress Syndrome. As a result, the roles of its components are being studied in order to synthesize a mixture as a therapy for lung disease. In order to closely analyze the interaction between the protein and lipid components at the atomic level, molecular dynamics simulations were carried out on a model system containing a Palmitic Acid monolayer (as a substitute for the actual lipid monolayer) and surfactant protein-B (SP-B). The model system appears to maintain its stability through electrostatic interactions between the charged residues of the peptide and the hydrophilic head groups of the lipid, and also through interactions between the aromatic groups of the peptide and the hydrophobic tail region of the lipids. In order to determine the specific role of the charged residues, the four cationic residues were removed from the peptide in a mutant SP-B, which was also simulated in the model system. When the simulations of the mutant and the native were compared, it appeared that the presence of the charged residues affect the orientation and secondary structure of the peptide as well as the order of the lipids in the monolayer.

 

Holocaust Revisionism and its Underlying Discrepancies

Michelle Levian

Mentor: Chaim Seidler-Feller

University of California, Los Angeles

Holocaust revisionism is the theory that the Holocaust, the utter annihilation of six million Jews during the years of 1933 and 1945, was nothing more than a hoax. Revisionists attempt to downplay the figure of six million deaths by claiming that only one million fatalities occurred. Furthermore, they discount the evidence that extermination camps and gas chambers were built to systematically eradicate Jewish civilians. The objective of this study is to closely examine and analyze the evidence and motives behind the audacious claims of revisionist thinkers. In an attempt to comprehend the provocations of such potent assertions against historical facts that contain substantiated evidence, various analyses were performed. Upon examination it becomes conclusive that revisionists are individuals who are in complete denial that the Holocaust occurred. Additionally, revisionists, most of whom are of German decent, are greatly humiliated by the horrific wrongdoings of their ancestors. In an attempt to justify the actions of their ancestors, they refute the phenomenon as a whole. The topic of holocaust revisionism is of great academic relevance today. Prejudice and discrimination on the basis of race and gender is still rampant all over college campuses. Therefore, learning about the motivations of deniers is an essential component in combating further perversion of the truth.

 

Induction of a Hepatic Antioxidant Gene Following Dietary Administration of a Chinese Herbal Product

Huihui Li

Mentors: Stephen Bondy, Edward Sharman, & Kaizhi Sharman

University of California, Irvine

Several flavonoids found within Scutellaria baicalensis—an herb long used in Chinese traditional medicine for its anti-inflammatory, antibacterial and hepatoprotective properties—have been identified as potent antioxidants and inflammatory enzyme inhibitors. The current study was performed in order to evaluate the potential of this herb for restoration of liver functionality in older animals. The herb constituted 0.25% of the diet, which was fed for eight weeks to both young (8-week-old) and aged (25-month-old) C57BL/6 mice. Following administration of Scutellaria, RNA was prepared from the liver, and Northern blot analysis of an antioxidant gene, glutathione peroxidase, (GPX) and an immune-related gene, Complement B (C1B), were performed. The dietary supplementation significantly elevated levels of GPX over basal values in young but not old mice. Furthermore, such herbal treatment had no significant effect on C1B in animals of either age. It is concluded that this herb has limited utility in enhancing antioxidant or immune defenses of elderly animals, but in younger animals, Scutellari may be able to elevate levels of a key enzyme involved in detoxification of free radicals.

 

DNA-Protein Crosslinking from Guanine Oxidation: Sensitivity of Crosslinking to the Presence of Guanine Multiplets

Catrissa Lightfoot

Mentor: Eric Stemp

Mount St. Mary’s College

The 1-electron oxidation of guanine via the Flash-Quench Technique results in DNA-Protein crosslinks (Journal of the American Chemical Society, 2000, 122, 3585). It is known that the oxidation potential of guanine in DNA decreases in the order -GT- < -GC- << -GA- < -GG- < -GGG- (Journal of the American Chemical Society, 1996, 118, 7063). This study examines how DNA is affected in its ability to form crosslinks with protein by local DNA sequence. Three different oligonucleotides that contain -GGG-, -GGC-, and -GCG- sequences were synthesized. The DNA was modified by the addition of an amino group and conjugated to Alexa Fluor 350, a fluorescent dye, then purified by HPLC. Uv-vis and mass spectrometry indicated that the Alexa Fluor dye was successfully conjugated to the DNA strands. Crosslinking was observed for all of the sequences studied here and is not a simple function of guanine oxidation potential

 

Universal Multimedia Access With JPEG2000 And MPEG-7

Jongyu Lin

Mentor: Mehran Moshfeghi

University of California, Irvine

Universal Multimedia Access (UMA) allows scalable and adaptive delivery of multimedia to client devices with capabilities, such as display size and bandwidth. This is important for multimedia applications in consumer electronics, pervasive computing and mobiles applications. Conventional systems typically use a transcoding proxy to dynamically adapt the content for different clients, or pre-compute and store multiple representations of content on a content server. The former requires an additional server and is computationally expensive, while the latter wastes storage space. We have used some of the features of the JPEG2000 image compression standard to overcome these problems. JPEG2000 offers flexible decoding of images, where an image can be compressed once and decompressed different ways to provide resolution scalability, quality scalability, region of interest coding, spatial random access, and efficient lossless or lossy compression. MPEG-7 addresses the requirements of UMA by providing Description Schemes that support the adaptation of multimedia according to the capabilities of client devices. MPEG-7 Importance Hints are used to annotate the importance of different regions in an image and Spatial Resolution Hints are used to specify the maximum allowable spatial resolution reduction factor for perceptibility. We have developed a UMA system where the JPEG2000 Internet Protocol (JPIP) is used in a client/server architecture. With this system JPIP and XML-7 enable the client to make intelligent requests and download selected portions of the JPEG2000 code-stream from the server, thereby producing an optimal image.

 

New Dromomerycids (Mammalia: Artiodactyla) From the Middle Miocene

Matthew Liter

Mentor: Donald Prothero

Occidental College

The Sharktooth Hill Bonebed in the Round Mountain Silt, northeast of Bakersfield, California, is famous for its rich fauna of marine mammals and fish, but yields few identifiable terrestrial mammals. Recent discoveries have recovered several dromomerycid skulls and jaw fragments that were originally misidentified as "Palaeomeryx". Although the best skull is from a juvenile (possibly female) and does not have characteristic orbital horns of adult male dromomerycids, it can be identified by its short occipital horn, dentition, and size based on comparison with the dromomerycids in the Frick Collection of the American Museum of Natural History. The new specimen is most similar to Bouromeryx americanus, a typical late Hemingfordian-Barstovian taxon. This new material prompted a review of the species-level taxonomy of the Dromomerycidae, which has not been updated since Frick’s 1937 monograph. Most of Frick’s genera are valid, but the species are grossly oversplit. Using statistical techniques, we significantly reduced the number of species in each genus. All the primitive Hemingfordian species (marslandensis, sweeti) and subgenera (Probarbouromeryx, Protobarbouromeryx) are synonymized with Barbouromeryx trigonocorneus (Barbour and Schultz, 1934). Bouromeryx submilleri from the late Hemingfordian is still distinct based on size, but all the remaining late Hemingfordian-Barstovian species (milleri, parvus, madisonius, pawniensis, supernebrascensis, pseudonebrascensis) are indistinguishable, and synonymized with Bouromeryx americanus (Douglass, 1909). Likewise, the number of species of Cranioceras and Procranioceras recognized by Frick has been greatly reduced.

 

Systematics of the Middle Eocene (Uintan) Protoceratid Leptoreodon

Joshua Ludtke

Mentor: Donald Prothero

Occidental College

A recent re-evaluation of the primitive protoceratid Leptoreodon was undertaken to see if a large number of new finds from San Diego County improves the systematics work previously done. This artiodactyl, found in middle Eocene deposits from Texas, Utah, Saskatchewan, and Southern California, was formally divided into five species in the last published review of the genus. Being able to identify which of these species occurred when and where in the stratigraphic record is valuable to correlating the age of rocks across a wide expanse of western North America. Dozens of lower jaws and teeth from the Los Angeles County Museum, San Diego Natural History Museum, and University of California, Riverside, were measured with standard dial calipers and evaluated in light of characteristics used in the last review of the genus as it appears in Southern California. Measurements were compared to see if species could be distinguished via measurable characteristics instead of less quantifiable characteristics. Of the species previously recognized, five appear to remain valid. L. pusillus remains distinct through its small size. L. marshi and L. major differ due to the overall larger size of L. major, which also has a longer lower molar row. L. leptolophus and L. edwardsi differ little in their teeth sizes, but show a geographical trend and also have distinct looking fourth lower premolars. The most recently described species, L. stocki, does not appear to be distinct from L. edwardsi, and the two species should be combined.

 

Intercalation-Induced Changes in DNA Tertiary Structure Studied by Atomic Force Microscopy

Elaine Ly, Occidental College

Mentors: Megan Nunez, Mt. Holyoke University; Eileen Spain, Occidental College

Development of new drugs relies in part on understanding how a particular molecule interacts with DNA. To address this challenge, atomic force microscopy (AFM) is applied to three DNA molecule-systems. AFM can image DNA shape, condensation, and protein binding at the nanometer scale. Intercalators, such as ethidium bromide and octahedral ruthenium complexes, induce changes in the superhelical shape of DNA, producing an extension, unwinding and stiffening of the DNA helix. A few groups have demonstrated supercoiled characteristics using air and liquid AFM studies of pBR322 with ethidium bromide, but no one has yet studied the effect of intercalating octahedral metal complexes on DNA by AFM. Studies of the plasmid DNA, pBR322, will be conducted using TappingMode AFM in both air and liquid to observe these transformations, which are caused by the untwisting of base pairs and helical backbone needed to accommodate the intercalator between the DNA base pairs. We will investigate the structural transitions in the plasmid DNA in response to Ru2+ intercalation. Currently, studies are in progress to collect a diverse set of images with and without the Ru2+ intercalator, to determine what tertiary structures are formed, and whether this complex does indeed intercalate into DNA.

 

LC-MS-MS Analysis of the Nucleoside Reverse Transcriptase Inhibitor Lamivudine (3TC) in Human Hair

Larissa Madrid, University of California, Irvine

Mentors: Francesca Aweeka, University of California, Irvine; Anura Jayawardene, University of California, San Francisco

Techniques such as measuring drug concentrations in plasma and urine have been evaluated for the determination of adherence to antiretroviral therapies; however, these methods are limited to short term (1-2 day) behavior assessment. Unlike the aforementioned methods, hair analysis shows potential for less invasive therapeutic monitoring and assessing long-term adherence because the level of drugs in hair reflects uptake from the systemic circulation over an extended period of time (weeks to months). The focus of this study was to develop and validate a method of quantitating antiretroviral drug concentrations in hair samples from HIV-positive subjects. This detection method was developed using liquid chromatography-tandem mass spectrometry to measure drug concentrations in hair, specifically targeting the nucleoside reverse transcriptase inhibitor (NRTI) drug 3TC, which is used to treat HIV infection. Calibration standards and quality control samples were prepared and used during validation to assess accuracy and precision of the method. Azidodideoxyuridine was chosen as an internal standard for this assay. The 3TC hair extraction and quantitation method will be validated according to AIDS Clinical Trails Group guidelines. HIV-positive subject hair samples will then be analyzed using this validated method with quality control samples to further substantiate the method. This form of hair analysis will have future implications in therapeutic monitoring of NRTI effectiveness in HIV patients.

 

Byzantium and Russia: The Orthodox Church as a Venue for Progress

Michael Marakhovsky

Mentor: Barisa Krekic

University of California, Los Angeles

When one studies history, it is often presented in blocks, broken up according to some national or chronological principle. However coherent such divisions might be, they fail to highlight the fact that throughout history, connections between nations and regions were of primary importance in pushing the progress of these areas. This consideration becomes of supreme importance when we examine the history of Russia. Russia is a state that played a huge role in forming the world that we live in, both politically, with the Cold War just the latest major influence, and culturally. The history and the role of Russia nevertheless cannot be properly understood until we examine its connections with the Byzantine Empire and the enormous influence that it had in forming the Russian state. Through religion, through culture, and through direct political connections the Byzantine Empire helped define the Russian character and state, and, through this inheritance, continues to influence the world today. This presentation will follow the unfolding story of this exchange focusing on key points in the relationship – those moments where this connection proved to be a crucial factor in determining the future of Russia.

 

The Murals of Diego Rivera: Political Expression and Propaganda Through Art

Claire Markgraf

Mentor: Linda Stark

Occidental College

Throughout history, artistic expression has served as a means to better understand the human experience. Poets, musicians, authors, and painters retain the unique ability to fuse dissimilar and seemingly opposed ideas, revealing complexities and dimensions of an issue that could not be realized through any other medium. Often, turmoil and great social disruption give rise to a torrent of expression through art as people and societies grapple with their changing surroundings. Mexico’s famed painter Diego Rivera (1886-1957) lived through the most significant and explosive period of the 20th century socialist/communist movement. Using his distinct fresco style, Rivera created hundreds pieces of art through which he expressed his support of the movement and its Marxist ideals. Rivera’s art came as revolutionary, providing the world with a visual commentary on the status of the proletariat in a market-driven society. As an acclaimed muralist, Rivera captured considerable media attention and was able to propagate the social messages of his work to the masses. While this elicited strong support in some places, Rivera’s works brought impassioned refutation from many, influencing public policy in the United States and abroad. It is this highly expressive and influential art that I have researched in order to understand better the intricacies of incorporating artistic expression with political thought.

 

The Staples Center: Urban Regeneration In Downtown Los Angeles

Chris Martin

Mentor: Stephen Koletty

University of Southern California

From 2000 to 2002, the Staples Center in Los Angeles held the national spotlight as it hosted three consecutive NBA championships. The Los Angeles Arena Company just completed construction of this new downtown events center in 1998. The new arena plays host to several of Los Angeles’ well-known professional sports teams, and also serves as a meeting place for conventions. Staples Center was designed to be the anchor, and the stimulus for a large-scale urban renewal process taking place south of downtown Los Angeles. As a result of the arena’s success and popularity, new development is taking place and is transforming its neighborhood. Investors have undertaken several multi-million dollar residential and commercial developments. The Staples Center is an example of a larger trend in American cities, as arenas and stadiums are constructed in downtown landscapes to encourage the renewal of the inner city. By constructing "a large draw," cities hope to create a jumping-off point for further development. This paper examines the success of the Staples Center in stimulating urban renewal in Los Angeles and contrasts this with the mixed results experienced in other cities that have employed this strategy.

 

Long-Term Study of the Effects of Dietary Jojoba Oil on Plasma Lipoprotein Concentrations in New Zealand White Rabbits

Christopher Martinez

Mentor: Raymond Garcia

California State University, Los Angeles

High levels of high-density lipoproteins (HDL) and low levels of low-density lipoproteins (LDL) are indicators of a low risk for the development of atherosclerosis, while the inverse is indicative of a high risk. Previous studies in our laboratory have shown that female New Zealand White rabbits fed a 2% jojoba oil diet for seven days results in a significant increase in HDL-C concentration. Our objective is to determine whether or not this effect of dietary jojoba oil on HDL-C concentration persists beyond the seven-day bleeding period. This objective was achieved by feeding female New Zealand White rabbits a rabbit chow supplemented with a 2% (w/w) jojoba oil for 0, 14, 28, and 39 days. Blood was collected from an ear vein and serum was obtained by centrifugation. The HDL fraction was separated from the VLDL+LDL fraction by polyanion precipitation of the serum, and total cholesterol (free cholesterol + cholesteryl ester) concentration was measured enzymatically. The results show an increase in the HDL-C concentration from 0 to 14 days, but a steady decline thereafter. Unlike HDL-C concentration, however, VLDL + LDL-C concentration exhibits a continuous increase throughout the entire feeding period. This suggests that dietary jojoba oil has an optimum period for increasing HDL-C concentration that is between 7 and 14 days. The reason for the inverse relationship in the level of HDL-C and VLDL+LDL-C after 14 days is unknown. Perhaps cholesteryl ester transfer protein is involved since it is a metabolic link between these two lipoprotein fractions.

 

Identification of Phosphorylation Sites in Fibrinogen by Combination of Affinity Chromatography and Mass Spectrometry

Daisy Martinon

Mentor: Agnes Henschen-Edman

University of California, Irvine

The intent of this study is to test if the Fe+3-chelate-Sepharose column affinity chromatography in combination with mass spectrometry can be utilized to selectively identify phosphorylation sites in fibrinogen. Fibrinogen is a central protein in blood coagulation. The increase in fibrinogen phosphorylation after elective surgery may be linked with the increased risk of thrombosis in these patients. An in depth study has not been made whether conformational and/or functional changes occur in fibrinogen as a result of phosphorylation. So far the complete set of phosphorylation sites in fibrinogen is only known for the human protein. It is important to isolate fibrinogen phosphopeptides with the most efficient method to analyze the functional relevance of phosphorylation. To test the method’s efficiency, horse and sheep fibrinogen tryptic digests were fractionated on an Fe+3-chelate-Sepharose column. All samples of peptides that showed affinity for the column were partially treated with phosphatase. A mass spectrometer was used to observe a subsequent phosphate group loss of 80 Da mass units in order to verify the presence of these groups. The analysis confirmed the 80 Da shift in the phosphatase treated peptides, thus proving that the Fe+3-chelate-Sepharose column affinity chromatography is an efficient method for isolating fibrinogen phosphopeptides. In horse and sheep species, eight and 10 phosphopeptides were observed, respectively. The peptides will be further identified by amino acid sequence analysis to determine positions of phosphorylation, which will be helpful for the understanding of the contribution to conformation and function in fibrinogen.

 

Activation of PI-3/Akt Pathway by Estrogen and Testosterone in Male Cerebral Blood Vessels

Kevin Marx

Mentor: Diana Krause

University of California, Irvine

It has been shown in brain blood vessels that estrogen increases vasodilation whereas testosterone enhances contraction of the vessel. A key regulator of vascular reactivity is nitric oxide (NO), a vasodilator produced by vascular endothelium. Phosphorylation of the kinase Akt (p-Akt) via PI-3 kinase is an important pathway for activating endothelial NO synthase (eNOS) to produce NO. We tested that hypothesis that estrogen and/or testosterone would affect Akt phosphorylation in male rat cerebral blood vessels. For acute treatment studies, blood vessels were isolated from orchiectomized (ORX) males and incubated (30 min) with estrogen (1 nM, 10 nM) or testosterone (10 nM, 100 nM or 1m M). In the chronic study, rats were divided into three groups with two groups treated with hormone for four weeks: ORX (control), ORX with 17b -estradiol (ORX+E), and ORX with testosterone (ORX+T). Blood vessels were isolated from the brains, and levels of p-Akt were determined using Western blot analysis. Both chronic and acute estrogen treatment increased p-Akt protein levels compared to ORX controls. Unlike estrogen, chronic testosterone treatment did not alter p-Akt protein levels in male cerebral blood vessels. However, acute treatment with testosterone did increase p-Akt. Because testosterone can be converted to estrogen via vascular aromatase, further studies are needed to determine if this hormone acts through androgen or estrogen receptors. Together, however, these results show that both steroid hormones, estrogen and testosterone, acutely regulate Akt phosphorylation. Activation of this kinase would be expected to increase production of NO in cerebral blood vessels.

 

Solving an Engineering Problem Utilizing a Beowulf Cluster

William Maxwell

Mentor: Meng-Lai Yin

California State Polytechnic University, Pomona

In the complex world of business and engineering the need to come up with solutions quickly is growing rapidly. In the information age modeling has become a critical part in the business product development cycle. With the increasing modeling complexity, obtaining modeling and/or simulation results can be very time-consuming. The need to produce time-efficient solutions is a driving force of this project. The purpose of this project is to develop low-cost high-performance computing solutions. In particular, the problem was checking the availability of a Global Positioning System across the United States. The entire area of the continental United States is divided into 500 grid points, and each point has its availability calculated over a 24-hr period. The solution developed was the implementation of a 12-node Beowulf cluster running both the Message Passing Interfacing and Parallel Virtual Machine environments. This presentation addresses the nature of the problem and the implementation of the best cluster solution.

 

"This Haunted Grove": Liminality, Ireland, and Authority in A Midsummer Night’s Dream

Corey McEleney

Mentor: Arthur Little

University of California, Los Angeles

Many critics have addressed the structural opposition between Athens and the woodland in A Midsummer Night’s Dream, arguing that the woods subvert the authority of Athens’ rigidly hierarchical court. Taking these interpretations as departure points, this paper places the relationship between Athens and the woodland in conversation with English relations with and representations of Ireland. While several studies have examined the references to Ireland in Shakespeare’s history plays, few have pointed out how Shakespeare’s construction of the wood in A Midsummer Night’s Dream symbolically and thematically draws on deep-rooted English conceptions of Ireland. Using Victor Turner’s model of liminality to set up my argument, I begin with close readings of both Shakespeare’s play and Gerald of Wales’ History and Topography of Ireland (1185) to investigate the relationship between the threatening liminality of Ireland and the threatening liminality of the early modern theater—a relationship with added gravity in this context, given Andrew Hadfield’s suggestion that the repression of Ireland in Shakespeare’s plays was effected by the regulation and censorship of the theater. A Midsummer Night’s Dream is an ideal text to analyze, then, since it metatheatrically directs criticism against an authority that (dis)regards the theatrical as mere trifle. The woodland of A Midsummer Night’s Dream thus emerges not only as an indicator of how Ireland might be read into the liminal spaces of Shakespeare’s plays, but also as the site of Shakespeare’s interrogation of England’s cultural authority (to regulate the theater) and imperial authority (to oppress and repress Ireland).

 

Directed Single-Walled Carbon Nanotubes on HSQ Patterned Surfaces

James McFarland

Mentor: David Tanenbaum

Pomona College

The interesting and unique properties of carbon nanotubes suggest a wide range of possibly revolutionary applications. From semiconductor manufacturing to materials science, the functionality of carbon nanotubes has remained mostly theoretical to this point largely because of our inability to position and manipulate individual nanotubes. One possible approach to such control is to use hydrogen silsesquioxane (HSQ), a negative tone glass resist, to pattern structures on top of catalyst pads, forcing directional growth of the nanotubes. Before obtaining directional growth using HSQ structures, however, it is important to understand and characterize the general process of growing nanotubes on these structures. We present such an investigation using CVD growth of carbon nanotubes on various patterned HSQ structures. Our results show a wide range of tube densities, often with predictable growth patterns. We were also able to successfully manipulate nanotubes suspended on the HSQ structures with an AFM probe, suggesting possible future techniques to further control the position of the tubes.

 

Testing a Model to Explain the Different Phenotypes of Lines Derived from the Same P-Element Insertion

Angela McGuire

Mentor: Catherine McElwain

Loyola Marymount University

We have established more than 100 lines of flies derived by P-element transposition from a single line of flies carrying a white-bearing P-element on the right arm of the third chromosome. In this original line the red pigmentation associated with the expression of the white gene in the eye is limited to a stripe across the middle of the eye. Some of these derivative lines have white eyes and probably represent the excision of the original P element. Some of the lines have red eyes and probably represent insertion of the original white-bearing P into a different location on the third chromosome. Some of the lines retain the striped pattern, although the phenotype of the stripe is quite different from the original line. These stripes vary in width, intensity, pigmentation in the flanking regions dorsal and ventral to the stripe and the continuity of the stripe. We are testing a model that predicts that these derivative lines, which still retain a striping pattern, result from the excision and reinsertion of the original P-element into sites close to the original site (local hopping). Furthermore, we predict that at least one of these stripe characteristics will correlate to the position of the insertions along the chromosome. We will present evidence to support the assertion that the derivative lines represent local hopping, and that the phenotypes can be classified along at least one continuum.

 

Salinas Valley Water Table Elevations: A Visualization Using GIS

April McMillian

Mentor: Douglas Smith

California State University, Monterey Bay

Solving California’s significant water crisis requires water management plans that take into account historic trends in local groundwater systems. By understanding how groundwater elevations have changed over time, predictions and water management policies can be made to ensure the quality and longevity of groundwater resources in California. Animations of historic water table elevations can effectively communicate water table behavior to many people through the visualization of problems and identify possible causes. Calibrated model water table data for the Salinas Valley were obtained form the Monterey County Water Resources Agency. These elevations were color contoured and mapped for consecutive years from 1949 through 1994. These maps were animated to show the changes the Salinas Valley water table has undergone from 1949 through 1994. Water table elevations declined in the lower Salinas Valley and coastal areas during the period of 1949 to 1957, and from 1983 to 1994. Water table elevations in the upper Salinas Valley, fed by two reservoirs, remained relatively stable through time, with minor changes due to precipitation. Increases in water table elevations are shown in all areas when the Nacimiento and San Antonio reservoirs began operation. Comparing these animations with previously published land use maps can identify possible links between land use practices and changes in water table elevations. Land use maps overlaid upon the contoured water table maps indicate that the City of Salinas lies at the center of a large zone of regional drawdown, suggesting municipal development may have large impacts on groundwater elevations.

 

Sequencing and Mapping Chromosome Breakage Junctions of Tetrahymena thermophila

Andrea Medina

Mentor: Eduardo Orias

University of California, Santa Barbara

The ciliate Tetrahymena thermophila is an excellent model organism for studying eukaryotic biology. Tetrahymena contains two genomes, the germline or micronuclear genome (MIC) and the expressed or macronuclear genome (MAC). The germline consists of five pairs of chromosomes. During macronuclear differentiation about 300 macronuclear chromosomes are generated by site-specific fragmentation of the germline chromosomes at chromosome breakage sites (Cbs). Using the 15bp Cbs sequence, the Orias lab has isolated and sequenced a fourth of the Cbs junctions. I have been mapping these junctions. Site specific primers are designed that flank each Cbs. Polymerase chain reaction (PCR) is used to amplify these junctions from MIC DNA. Nullisomic strains of Tetrahymena lack both copies of a chromosome or chromosome arm in their MIC. I use DNA from these strains and PCR to map each junction to a chromosome arm. When a junction contains a polymorphism, I am also able to map it to a MIC linkage group. The Tetrahymena genome is currently being sequenced, and this research will help relate the genetic and physical maps to the sequence.

 

Precision Photometry of the Microvariable Quasar 3C 66A

Erik Mendoza

Mentor: Stephen Gillam

California State University, Los Angeles

This paper describes the results of a short observing run of 3C 66A on January 13, 2003 at Table Mountain Observatory with the 0.6 m telescope and 2K CCD camera. The purpose of the observation was to contribute data to the characterization of the variability of 3C 66A. The reduction procedure is described in great detail, as well as all of the analysis procedures. We employed two standard stars in the same field for differential magnitudes. Furthermore, results from the reduction process provide information on the precision of the new 2K CCD camera used.

 

For the Dream: An Artistic Exploration of Unity

Angela Miller

Mentor: Maxine White

University of Wisconsin, Whitewater

This 55" X 72" visual art piece is a hybrid between painting, illustration and sewing. The first layer of the canvas (the back layer) was influenced by the work of Jackson Pollock, which suggests a style of "action" painting to represent hectic energy. This layer utilized several colors and throwing techniques. The second (or top) layer was cut into various pieces, which were sewn together with a "dead" area between the pieces. This "dead" area allows one to view parts of the back layer once the canvas layers are placed on top of each other. The conceptual material on the top layer has charcoaled anatomical studies with different perspectives. In each of the top layer’s section backgrounds is an excerpt, written in different languages, from Martin Luther King Jr’s "I Have a Dream" speech. The conceptual message that this piece creates relates to the idea of equality. It conveys the message that we all are human and the same because we share many similar thoughts, feelings, and experiences. Our differences are the result of our different positions in life’s journey. These differences are all temporary, however, and we are one people in the final analysis.

 

Viologens Capture by Polymer-Supported Crown Ethers

Kent Miller

Mentor: Fraser Stoddart

University of California, Los Angeles

Paraquat, a viologen, is one of many pesticide poisons. It acts as an executioner on many vital organs of the human body. Paraquat is a commonly used pesticide in agriculture and often its levels become too concentrated in places in the environment. However, nanotechnology allows us to solve this problem. It is theorized that, through supramolecular chemistry, Merifield resin beads can be functionalized with crown ethers that complex with the viologens, making pseudorotaxanes. The complexation of the two components will make the viologen more recognizable and easier to gather from the environment. This hypothesis was tested first using a protocol, and the result was a glowing success. Of great significance was the ability of using environmentally safe chemical synthesis as a way to solve an environmental problem.

 

Extraction, Isolation and Characterization of Rhizobia from Woody Legume Root Nodules

Heather Mitchell

Mentor: James Blauth

University of Redlands

Woody legumes, with their deep root systems and mutualistic relationship with rhizobia, can serve to assist in the re-vegetation of disturbed arid lands. Woody legumes are a part of the legume family that is characterized by their ability to produce wood. Rhizobia are the nitrogen-fixing bacteria that dwell in the root systems of legumes. By extracting, isolating, and characterizing rhizobia from legume-dominated desert areas, it will be possible to determine the optimal combination of rhizobia and legumes for restoration efforts. Through various tests such as culturing on specific media, Gram staining, and carbon source testing, we found that the rhizobia collected could be characterized into species-specific groups. Using nodulation assays and cross-inoculation tests, we gathered information concerning the nodulation abilities of the collected rhizobia. Further testing will allow for the determination of rhizobia specificity to legume hosts. By using rhizobia and woody legumes it may be possible to start a natural succession of desert life in disturbed arid lands at relatively low cost.

 

The Effect of Prostaglandin E2 on Human Dendritic Cell Phenotype and Function

Kathleen Mitchell, Loyola Marymount University

Mentors: Russell Salter & Simon Watkins, University of Pittsburgh

Dendritic cells (DCs) mature following antigen uptake and travel to lymph nodes in order to stimulate naive T-cells and initiate immune responses. Immunotherapy using mature tumor antigen-loaded DCs has been used effectively to treat some cancers in clinical trials, but the inability to ensure that these DCs will move to lymph nodes and initiate a proper and successful immune response limits their utility. The standard method for maturing DCs for in vitro and in vivo clinical trial use is monocyte conditioned media (MCM) with tumor necrosis factor alpha (TNF-alpha) and prostaglandin E2 (PGE2). The use of PGE2 has recently been debated because of evidence that it decreases IL-12p70 and IFN-gamma production, which leads to a Th2 biased response. We tested the effect of PGE2 in the MCM/PGE2/TNF-alpha maturation mixture on human peripheral blood monocyte derived DCs. The DCs were then measured for T-cell stimulatory capacity (defined by T-cell proliferation in MLR), immunophenotypic maturity (defined by upregulation of CD83, also CD86, CD80, and MHC Class I and II), and motility (defined by movement along a collagen-coated coverslip in live cell imaging analysis) in vitro. Our data suggests that DCs matured in a media containing PGE2 had lower levels of CD83 expression, a lowered ability to induce T-cell proliferation, and a lowered percentage of mobile cells. Our data suggest that DCs matured with MCM/TNF-alpha may be a more functional option for in vitro study and most importantly for in vivo clinical use.

 

A Comparison of Post-Injury Compensatory Fiber Outgrowth in the Male and Female Rat Cholinergic System Under Varying Lengths of Estrogen Treatment

Bibhu Mohanty

Mentor: Sonsoles de Lacalle

California State University, Los Angeles

Alzheimer’s disease is one of several illnesses known to result in dementia, which is characterized by loss of memory, behavioral impairments, and diminished ability to carry out simple daily functions. Numerous studies have linked the prevalence of such symptoms in post-menopausal women to a lack of estrogen. Estrogen is thought to be a key modulator in the function and maintenance of cholinergic neurons in the basal forebrain. Our laboratory has described in vitro estrogen induced increases in neurite size and number in cholinergic neurons. Based on those findings, we hypothesize that such estrogen-induced changes could occur post-injury at the axonal level, and that a compensatory sprouting effect could be beneficial. To address this issue, we have started to study the effects of estrogen treatment on males, in addition to females, which have traditionally been the focus of many such studies. The immunotoxin 192 IgG-Saporin was used to make a lesion in the horizontal limb of the diagonal band of Broca, a group of neurons in the basal forebrain that project to the entorhinal cortex. Lesioned rats of both sexes were then treated with either four or eight weeks of estrogen and subsequently, the brains were sectioned and histochemically prepared to analyze the effect of hormonal treatment on compensatory fiber outgrowth. Our results indicate that while sprouting occurs at similar levels in both sexes when treated with four-weeks of estrogen, after eight weeks of estrogen, there are significantly greater levels of sprouting in males than females.

 

Parent-Child Co-Sleeping: Where Do Fathers Fit In?

Marshall Moncrief

Mentor: Wendy Goldberg

University of California, Irvine

Parent-child co-sleeping (parents and children sleeping together on a shared surface, typically the parents’ bed) is one of the leading sources of contention today in the area of early childhood and familial well being. Empirical data are beginning to emerge concerning variations in family sleep arrangements, and the effects of co-sleeping on infant well being, early child development, and family interactions (McKenna, 2000; Keller & Goldberg, in press). However, very little information is available with regard to fathers’ views toward family sleep practices, especially co-sleeping. In this study, which is the first phase of a two-part investigation of the fathers’ role, data are reported from questionnaires completed by more than 100 mothers of preschool-aged children. (The second phase will focus on direct assessments of the fathers). The research question driving this study was "To what extent are fathers involved in decisions about family sleep arrangements and what are the correlates of their involvement?". The major objective of this first phase was to examine the associations between fathers’ inclusion in and support of the choice of family sleep practice and mothers’ reported satisfaction with that practice as well as overall family wellbeing. Preliminary findings of this study indicate that when fathers are perceived by mothers as being highly supportive of sleep arrangements, mothers report being more satisfied with sleep arrangements. A preliminary descriptive analysis of the findings indicate mothers reporting more support from fathers for solitary sleeping than for co-sleeping. However, in cases where children are displaying sleep problems, mothers report high support from fathers for co-sleeping arrangements. Further analyses will address whether or not father support, father satisfaction, and marital satisfaction will vary by the type of sleep arrangement (solitary sleeping children, co-sleepers, and reactive sleepers).

 

Genome Stability within the Human Cancer Cell Lines HeLa, MCF-7, and HL-60

Celina Montelongo

Mentor: Douglas Swartzendruber

Pepperdine University

With the advent of human cell culture came the possibility of retaining human cells viably in continuous culture indefinitely. The changes that might occur within the genome of these cells after they are removed from the human body and passaged continuously in vitro raise the question of the genomic stability of these cells in culture. This study quantified genomic differences existing within the human cancer cell lines HeLa, MCF-7 and HL-60 collected from different laboratories. Using flow cytometric analyses to determine DNA indices, it was found that these three lines are consistently aneuploid. Within the HeLa and HL-60 cell line, no two laboratories provided cells with the same DNA content. While two of the MCF-7 lines were very similar, the third line contained almost 75% less DNA. The three lines HeLa, MCF-7 and HL-60 are not genomically similar within their respective cell lines across laboratories, and are thus not genomically stable. These results may impact the validity of the experimental research that has utilized these cell lines.

 

Zapatista Feminism: The Importance of Women within a Movement

Ana Morales

Mentor: Maria Elena Martinez

University of Southern California

This research paper analyzes the gender roles that women play within the EZLN (Zapatista Army for National Liberation) and Maya communities of eastern Chiapas more generally. It also studies the changes Maya women experienced in their communities, as the EZLN became a more dominant influence in their lives. The main purpose of the paper is to understand the role women play in the EZLN community and the social changes that have come out of Zapatista feminism. In order to explain those changes, it begins with an historical overview of Maya indigenous struggles of eastern Chiapas and of the relationship of indigenous communities in that region with the central Mexican government and Zapatismo, the movement inspired by the peasant leader of one of the main factions of the Mexican Revolution, Emiliano Zapata. The paper then covers specifically how the EZLN has affected women in these Maya communities and what significance has come from it. It ends with an analysis of the literature and discussion of further research on this topic.

 

Use of an IVET System to Identify Periplasmic Regulated Genes in the Bacterial Predator, Bdellovibrio bacteriovorus

Ryan Murphy

Mentor: Mark Martin

Occidental College

Bdellovibrio bacteriovorus is a relatively uncharacterized bacterial predator of other Gram negative bacteria. In an effort to better understand this "genetically undomesticated" organism, we have been developing an in vivo expression technology) in order to identify Bdellovibrio genes expressed in the periplasm of host cells. Sau3A cut Bdellovibrio genomic DNA was cloned into pSVS101 (modified from pIVET8). Successful clones expressed different levels of chloramphenicol resistance, depending on promoter strength of the Bdellovibrio DNA inserted. A "bank" of such clones was mobilized into wild type Bdellovibrio, and allowed to attack E. coli host cells. Chloramphenicol was then added. Clones isolated following this procedure may be periplasmically expressed. We believe that this approach, because it is non-directed, will provide insights into how Bdellovibrio carries out its predatory lifestyle inside host cells.

 

DNA Sequence Matching Processor

Jane Nawilis

Mentors: Yi Cheng & Meng-Lai Yin

California State Polytechnic University, Pomona

The objective of this senior group project is to design and implement a high-speed DNA sequence matching processor using Verilog HDL programming language and a Xilinx Field Programmable Gate Array (FPGA) board. With the exponential growth of the DNA research, searching an unknown DNA sequence in existing database could be very time-consuming. Performance becomes a crucial factor in DNA sequence searching, which motivates this project. Our approach is to utilize the parallel processing capability available on the FPGA board, where multiple comparisons can be done simultaneously. In particular, this processor looks for the exact-matched sequences from an existing data bank, e.g., a portion of the GenBank (NIH genetic sequence database) in a "pipeline" fashion. Theoretically, after the initial setup, this processor can compare n DNA pairs at the same time, thus improving the performance by a factor of n. The sequence-matching module written in Verilog HDL is downloaded into the FPGA board using the Xilinx-provided software and the simulation tool ModelSim. Our initial result is encouraging, which shows that, with the processing power of the FPGA, the search time is significantly reduced. This project continues after the first year’s experience, and more DNA searching algorithms are being studied and implemented using this parallel processing approach.

 

The Rita Stories: Writing Life & Death

Alexis Nelson

Mentor: Robyn Bell

University of California, Santa Barbara

Since the 18th century, biography has been a popular literary genre. However, our most celebrated biographies give accounts not of ordinary people’s lives, but of the lives of famous historical figures. There’s Boswell’s Life of Johnson, for example, or Twain’s biography of Joan of Arc. Yet Johnson himself, when advising Boswell about his writing, said, "There is nothing too little for so little a creature as Man. It is by studying the little things that we attain the great knowledge of having as little misery and as much happiness as possible." Although few of us are fortunate enough to know any "famous historical figures" as well as Boswell did, most of us do know people whose lives we celebrate privately. These people lead lives that an outsider would deem little or ordinary, but that we who admire them look upon as heroic. My best friend’s mother Rita is one such person for me. "The Rita Stories" began four years ago, as a few scattered pieces about my relationship with her. I have since collected and built upon these stories, creating a single work of substantial length that covers the breadth of our relationship, beginning in my adolescence when I first became friends with her daughter and was welcomed into her home, and ending one year ago, with her death. My "Stories" paint a mosaic-like portrait of Rita as I knew her—a mother, a mentor, a friend; in short, an extraordinary woman whose life story deserves to be told.

 

Which Form of Insulation is Most Effective?

Jessica Ng

Mentor: Wendy Cozen

University of Southern California

When the human body faces tough temperature changes, our body has to adapt to it. We need to rely on more than our air heating system to give a more tangible feeling of warmth. The objective of this project was to determine which form of insulation would be best at keeping the human body at a stable temperature. The testing variables are cotton, human hair, chicken feathers, wool, and a combination of 50% cotton and 50% polyester fabric. The controlled variable had no insulation. My hypothesis is that wool will be the most effective, while chicken feathers will be the least effective. To begin the project, I lined the inside of a plastic bag with one form of insulation material equally. Then I heated one cup of boiling water and placed it in a container. When the water temperature reached 183 F in the container, it was sealed and placed in one bag. The bag was stored in a 50 F environment. The container was removed from this environment, and the water was measured every 10 min. This process was continued for 120 min. The recorded data revealed that human hair was 122 F, thermal insulation was 120 F, cotton was 122 F, chicken feathers were 128 F, wool was 118 F, and the 50% cotton/50% polyester was 114 F (the controlled variable was 80 F). In conclusion, my hypothesis was wrong because it was found that chicken feathers kept in the most heat, while the 50% cotton/50% polyester material kept in the least heat.

 

Neutrophil Migration in Overlapping Chemoattractant Gradients

Connie Nguyen

Mentor: Noo Li Jeon

University of California, Irvine

Neutrophils are the polymorphonuclear leukocytes that respond to foreign pathogens or tissue injury and are involved in the body’s immune system. These mobile cells show chemotactic response to chemoattractant gradients, such as IL-8 (interleukin 8) and LTB-4 (leukotriene B4). Multistep migration, in which the neutrophil leaves local chemoattractant vicinity in response to a distant gradient, has been shown to play an important role in neutrophil recruitment and defense response. Previous studies have also shown that there is a hierarchy between bacteria-derived chemoattractants such as fMLP (f-met-leu-phe), and host-derived chemoattractants, such as IL-8 and LTB-4. The main purpose of this project is to verify the multistep migration model and to investigate if there is also a hierarchy between two host-derived chemoattractants, namely LTB-4 and IL8. We have developed a microfluidic device using soft lithography and PDMS to create stable overlapping linear gradients of IL-8 and LTB-4. Neutrophils were loaded to the chamber and time-lapse images of migrating cells were taken for analysis. The migrating cells were divided into two populations. The initial position of one population was closer to the IL-8 gradient and the other was closer to the LTB-4 gradient. A higher percentage of cells in both populations moved toward the distant gradient, implying that the multistep migration model is valid. Neutrophils migrated more effectively toward the LTB-4 gradient, suggesting that there may be a hierarchy between two host-derived chemoattractants, and LTB-4 is higher in the hierarchy than IL-8.

 

Diabetes and Macrosomia: The Effect of Maintaining Normal Blood Glucose Levels During Pregnancy and the Effectiveness of the Sweet Success Program

Donna Nguyen

Mentor: Sibylle Reinsch

University of California, Irvine

Macrosomia, the medical term for newborn infant weight greater than 4,000 grams, is a frequent outcome of diabetic pregnancies. Heavy newborns are at risk for injury during the birthing process and for developing diabetes later in life. Based on studies that demonstrated a reduction in macrosomia rates if blood glucose values were maintained within a normal range during gestational diabetes, the Sweet Success Program in Orange County, California, teaches pregnant women with diabetes balanced nutrition, exercise, and stress management so that their newborn will have a normal birth weight, which is between 2,500-4,000 grams. Other studies have shown, though, that despite intense glucose control during pregnancy, women with pre-existing diabetes had macrosomic infants at a rate six times greater than normal. This would suggest that the Sweet Success Program might only be effective with women who developed diabetes in the 3rd trimester of their pregnancy. To address this issue, I used a data set obtained with 645 Hispanic women in Orange County, and divided the women into three groups, depending on the trimester they were referred to the Sweet Success Program, with the reasoning that early referrals had to be due to pre-existing diabetes, and 3rd trimester referrals had to be gestational diabetes. Results, based on t-tests, showed no significant differences in the mean birth weight among the different groups. Those who entered during the 1st trimester had a mean birth weight of 3,483 grams, while those who entered during the 2nd and 3rd trimester had mean birth weights of 3,484 grams and 3,494 grams, respectively. The t-test also showed that the difference in mean birth weight among those who had pre-existing diabetes and those who had gestational diabetes, 3,606 grams and 3,472 grams respectively, would have occurred by chance only 5% of the time. This agrees with previous studies that claim that despite intense glucose control, women with pre-existing diabetes were still more likely to have macrosomic infants. More than 80% of the women had newborns of normal weight. Thus, the Sweet Success program seems to be an effective program for many pregnant women who have diabetes, pre-existing as well as gestational.

 

Application Mobility in Bio-Networking Architecture

Kevin Nguyen

Mentors: Tatsuya Suda & Junichi Suzuki

University of California, Irvine

The Bio-Networking Architecture (BioNet) is a decentralized network architecture that applies biological concepts to operate on large scale, highly distributed, and dynamic environments. This project builds the migration service part of BioNet that allows network applications (cyber-entities) to move from one place to another. In BioNet, network applications are mobile agents and are analogous to biological species that have behaviors, states, locations, and mobility. The migration service is responsible for sending and receiving cyber-entities between BioNet platforms. The migration service is composed of two components: ceSender and ceReceiver. When a cyber-entity has enough energy to migrate, the ceSender serializes and sends the entity’s state, class definition (entity’s source code), and name to the destination platform. Upon receiving a migrating cyber-entity, the ceReciever uses class loader mechanism (Java programming language) to load the class definition and de-serializes the state of the cyber-entity. Then, the migration service initializes the cyber-entity and registers it to the current platform. The migration service acts as a bridge that allows cyber-entities to utilize their mobile capability. More importantly, this service allows Bionet platforms to scale in large systems by spreading cyber-entities around so the platforms do not collapse. This poster presentation overviews several common design strategies for mobile objects, shows the detailed design and implementation of the BioNet migration service, and demonstrates several results of its performance measurement.

 

Targeted Mutagenesis of the Genes flin-7 and flin-10 by Homologous Recombination in Drosophila melanogaster

Sheila Nguyen

Mentor: Peter Bryant

University of California, Irvine

The fruit fly Drosophila is a powerful model system to identify the genetic mechanisms that are perturbed in cancer cells, and it is especially useful for the identification of novel tumor suppressor genes. One of the best studied of these genes is lethal(1)discs large-1, encoding the Discs large (Dlg) protein, which functions in the larval brain and imaginal discs. Preliminary evidence indicates that Dlg may exert its tumor suppressive function by regulating the localization and/or function of DER (the Drosophila Epidermal Growth Factor Receptor) either directly or through its interaction with the putative cytoskeletal proteins Flin-7 and/or Flin-10. To test these ideas, I am producing genetic mutations of flin-7 and flin-10 using homologous recombination, a new technique that uses DNA repair and recombination mechanisms to replace normal DNA with exogenous mutant DNA at a target locus, mediated by sequence homology. In order to create the necessary DNA constructs, I have developed a strategy using pGEM-T as an intermediate cloning vector, which enabled me to increase the efficiency of the subcloning into pW25, the final vector, and to successfully engineer the flin-7 construct. Using a similar approach, I am in the process of subcloning flin-10 into pW25. In parallel to this second subcloning procedure, I am injecting the flin-7 construct into fly embryos and screening for both transformant flies and flin-7 mutants. The study of the phenotypic defects of the flin-7 and flin-10 mutants should show whether the gene products have the suggested functions in controlling cell proliferation.

 

Auditory Cortical Potential (N100, P200) to Gaps in Noise in Normal Hearing and Auditory Neuropathy Subjects

Tin Nguyen

Mentor: Arnold Starr

University of California, Irvine

The objective of this project is to use electrophysiological methods to study cortical potentials to gaps of different durations. Auditory potentials to gaps were recorded from 12 normal subjects. Gaps of 2, 5, 10, 20, and 50 ms in noise (60 dBnHL) were randomly presented every 2 sec. Subjects were tested in two conditions: (1) press a reaction time (RT) button to a detected gap and (2) listen without behavior. Trials to gaps were averaged and measures of peak latency and amplitude of components N100/P200 were computed. Accuracy was ~99% for 50, 20, and 10 ms gaps, 73% for 5 ms, and 17% for 2 ms gaps. RTs averaged ~292 ms to 50, 20, and 10 ms gaps, 352 ms for the 5 ms gap, and 421 ms for the 2 ms gap. N100 and P200 were identified to gaps between 50 and 5 ms. N100 and P200 amplitudes were significantly decreased when gap durations were less than 20 ms; peak latency differences among gap durations were not significant. Accuracy, RT, and N100 and P200 correlated with gap duration. These methods provide a tool to study temporal processes in hearing disorders and mechanisms of central auditory processing.

 

Conflict Detection on the Activation of the Attachment System

Tryston Nguyen

Mentor: Shelly Gable

University of California, Los Angeles

This study examined the effect of conflict detection on the activation of the attachment system, the system that monitors for psychological distance from others. Attachment theory posits that when infants face threatening situations, the attachment system is activated in order to lessen the distance between the child and caregiver to promote safety. This study hypothesized that one major form of threat is ‘conflict,’ the indication that something is wrong. Once conflict has been detected, the activity of the attachment system should be heightened, such that individuals become more sensitive to indicators of psychological distance from others and more motivated to reduce this distance. In this study, participants completed a Stroop task (conflict) or a color-naming task (no conflict) and then decided whether several types of words (psychological closeness: ‘support;’ psychological distance: ‘rejection;’ neutral words: ‘computer’) were real or not. We predicted that the conflict condition would heighten the sensitivity of the attachment system and thus the accessibility of psychological distance words. Though we found no main effect of conflict on reaction times to distance words, we found that individuals higher in neuroticism or trait anxiety, associated with a more sensitive conflict detection system, showed quicker recognition times to distance words in the conflict condition. We discuss the relationship between anxious temperament and the sensitivity of the attachment system.

 

Titin-Mimicking Multi-Domain Polymer Synthesis

Vivian Nguyen

Mentor: Zhibin Guan

University of California, Irvine

There are three important properties for material performance: strength, toughness and elasticity. Naturally occurring materials, such as the muscle protein titin, have combined these three properties. In my pursuit of synthesizing an organic compound with optimum material performance, I have strived to mimick the properties of titin consisting of multiple domains held together by strong, specific hydrogen bonds. Creating such a synthetic material would be very useful to commercial industry. Not only can such materials experience high force, but they can also be extended, proving to be strong, tough, and somewhat elastic all at the same time. In attempting to make a synthetic polymer that exhibits these qualities, I have been working on making the monomers that will link together and form a repeating polymer. In doing so, I have learned that the concepts taught in a chemistry lecture hall are not absolute truths. The chemicals do not always behave the way the books say they will behave. Many of the reactions did not work as I had planned, giving unexpected results. A minor change in the setup, such as a different solvent, has made all of the difference. I have greatly broadened my skills and chemical techniques in the laboratory, but most importantly, I have realized that chemistry is not as exact a science as I thought it would be. Concepts presented on the blackboard many times fail in practice, and it requires creative thinking to come up with new systems that are applicable to each organic synthesis.

 

Radiative Transfer Model Fitting to Describe the Properties of Class 1 Protostars

Kevin Nielson

Mentor: Susan Terebey

California State University, Los Angeles

When describing the formation of stars, it is difficult to make direct correlations between observations and the properties of the objects in question. While direct interpretation of astronomical data may not lead to good stellar characterizations, an alternative exists in the realm of stellar modeling. By creating a library of models of varying characteristics, including age, cavity angle, cloud density, and inclination, we can match model profiles to observed objects and infer similar characteristics for the observed object as were used to generate the model. Here we compare the profile of Monte-Carlo radiative-transfer (RT) models to Hubble Space Telescope data obtained for the class 1 protostar TMC-1 in the Taurus star-forming region. We find that the angular intensity profile can be fit well using RT models, with only a small discrepancy in background levels and some asymmetry not accounted for in the model. We therefore infer that TMC-1 has an outflow cavity width of ~80-90 degrees and is inclined toward us at ~50-60 degrees.

 

Mechanistic Investigation of Substituent Effects on Oxime Radical Cations

Olena Norris

Mentor: Peter de Lijser

California State University, Fullerton

Photochemistry of oximes and its use as a method for regeneration of carbonyl compounds has been of a growing interest; we focused our studies on various ortho-substituted acetophenone oximes. Studies were done to investigate the photochemical deprotection of acetophenone oximes to their corresponding carbonyl compounds through the use of photosensitized electron-transfer reactions. With existing knowledge of the reaction’s initial steps, our goal was to determine the reaction’s mechanism and its assosiated intermediates. The method of investigation involved the effects of the substituents on the reactivity of the oximes. The studies have shown that substituents have steric, electronic and radical effects. It was hypothesized that in order for electron transfer to be able to occur, the oxime moiety has to become coplanar with the aromatic ring upon ionization. Certain ortho-substituents seem to prohibit this alignment, as confirmed by semi-empirical calculations (AM1, DFT). Ortho-substituted acetophenone oximes were studied by X-ray crystallography, electrochemistry and fluorescence spectroscopy, data from these studies were compared to those from the photosensitized electron-transfer reactions.

 

The LHX2 Gene in Schizencephaly and Septo-Optic Dysplasia

Kelechi Nwede

Mentor: Edwin S. Monuki

University of California, Irvine

Schizencephaly and Septo-Optic Dysplasia (SOD) are two rare but related malformations of the human brain. In most patients with schizencephaly and SOD, the underlying cause remains unknown, although genetic defects have been implicated in a subset of cases. The LHX2 gene emerged as a candidate gene based on the brain phenotype of LHX2 knockout mice, which strongly resembles both human disorders. Our goal is to determine if mutations in the human LHX2 gene can cause schizencephaly or SOD. We are currently analyzing the LHX2 gene in a cohort of 25 patients. The experimental approach involves amplification of the LHX2 protein-coding sequences using polymerase chain reaction (PCR), followed by direct sequencing and computer-based sequence analysis. We have optimized the PCR and sequencing reactions for all five LHX2 exons and have almost completed the analysis of exons 2-4. Thus far, we have detected one potential mutation, which predicts a non-conservative amino acid change in a potential functional domain of the LHX2 protein. In addition, we have confirmed a single nucleotide polymorphism (SNP) known to exist in exon 4. A complete analysis of this patient cohort should determine whether LHX2 plays a significant role in these two human brain malformations.

 

What Does it Mean to be an African Feminist? Understanding African Feminism Through the Works of Contemporary Nigerian Women Writers

Nmachika Nwokeabia

Mentor: Tara Lake

University of California, Los Angeles

The Sharia Law cases involving Amina Lawal and Saffiya Hussaini in Nigeria, and the threat of women in the Delta region to strip in rebellion against the powerful oil companies presented two diametrically opposite views of the status of women in Nigeria. In literature, Buchi Emecheta, arguably Nigeria’s most widely read female author, may sometimes be seen as representing, in her characters, strong women that are nevertheless in conflict with Western ideas about feminism. She calls her brand of feminism, "feminism with a small ‘f’." African feminism is different from Western feminism in many ways, and critics have argued against trying to understand African feminism, especially as presented in literature, from the Western feminist perspective. "African feminist practice …reflects diverse historical and personal experiences that are outside of Western experiences. As a result, African feminism has constructed an alternative grid of values and priorities that cannot be conflated with those of Western feminism, even if some concerns are similar" (Petty, 1996). In analyzing some short stories from the collection "Inside My Sisters’ Eyes," I try to analyze African feminism from a traditional perspective and show how its flaws and strengths are derived from the African experience and its multilayered history.

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