H-N (pdf) O-Z (pdf) Groups (pdf)
Defective DNA Damage Response in Mlh3 and Mlh3/Pms2 Deficient Mouse Embryonic Fibroblasts
Mentor: Steven Lipkin
Multiple homologues of E. coli MutL participate in eukaryotic DNA mismatch repair (MMR) processes. In Hereditary Non-Polyposis Colon Cancer (HNPCC) families, MLH1 mutations are common while PMS2, MLH3 and PMS1 mutations are rare. Furthermore, DNA-damage response phenotypes in mice doubly deficient in Mlh3 and Pms2 are indistinguishable from Mlh1 deficient mice. Our data demonstrate that MLH3 plays a greater role in mammalian cancer prevention than previously believed. Partial functional redundancy between MLH3 and PMS2 for mutation avoidance and DNA damage induced apoptosis may explain why, among MutL homologues, only MLH1 mutations are common in HNPCC. Homozygous MLH1, MSH2, PMS2 and MSH6 (but not MSH3 or PMS1) mutant human and mouse cell lines demonstrate increased resistance to cell death and decreased levels of apoptosis in response to alkylating agents, such as 6-thioguanine (6-TG) treatment, a DNA alkylation mimetic. Following 6-TG exposure, Mlh3-/- mouse embryonic fibroblasts (MEFs) displayed increased resistance compared to wt cells, similar to Pms2-/- MEFs. Of further interest, the double null Mlh3-/-/Pms2-/- MEFs showed a degree of resistance greater than either the Mlh3-/- or Pms2-/- MEFs. To examine whether increased survival was attributable to lower apoptosis rates, TUNEL assays were performed. Consistent with previous studies, Mlh3-/-Pms2-/-, Mlh3-/-, and Pms2-/- MEFs showed reduced DNA damage induced apoptosis compared to wt MEFs. These results suggest resistance to apoptosis is an important mechanism of carcinogenesis in Mlh3 mutant cells.
Location-Aware Web Services
Mentor: Cristina Lopes
Location-aware systems are systems that display information according to the users location in the physical space. We have developed a location-aware system to be used within a building and as an extension of a Web service. The system can be separated into two distinct components: the positioning system and the protocol for exchanging location information between the clients and the web server. In this presentation we focus on the latter by introducing Location-Aware Web Services (LAWS), built on top of the Hypertext Transfer Protocol (HTTP). LAWS frees the system from having to maintain a dedicated connection for the exchange of location information. That information is embedded in the HTTP requests sent from the roaming device to the web server.
Childhood ADHD Symptomatology in Parents: A Risk Factor for Children with ADHD?
Mentor: Carol Whalen
Perceived sense of parenting efficacy and levels of parental psychopathology were compared between parents of children with ADHD who themselves had childhood symptoms of ADHD, and parents of children with ADHD who reported few such childhood symptoms. Children of each parent group were compared on mood profiles attained using electronic diaries. 24 parent-child dyads that included children diagnosed with ADHD who were being treated via a long-acting stimulant taken once daily were placed into one of two groups, based on whether or not the parent reported ADHD symptoms meeting diagnostic criteria as a child. Parents answered questionnaires that captured current symptoms of psychopathology and completed morning and evening diaries reporting perceptions of their own parenting efficacy throughout a week. Children were prompted to report the presence and intensity of positive and negative moods every half-hour throughout the week via electronic diaries. Parents in the childhood ADHD group exhibited significantly greater psychopathology than parents in the non-childhood ADHD group. Parents in the childhood ADHD group tended to report lower perceptions of parenting efficacy for morning diaries than parents in the non-childhood ADHD group. Mood profiles did not differ significantly between the child groups. Parents reporting a childhood history of ADHD may experience a diminished sense of parenting efficacy and high levels of psychopathology, in comparison to parents with few childhood indicators of ADHD. These findings have implications for the treatment of ADHD, suggesting that intervention should be targeted on parents as well as children.
Mentor: Donald McKayle
Quarter-life is based on a complete reassessment of me as an artist. This work discusses the theme of self vs. other. During the choreographic process I explored the connection between concert dance and fashion with designer John Sakalis and found that they are often hated and loved for their association with unique visual beauty. In this dance five dancers personify heaven, hope, chaos, earth and change. The choreography was based on my improvisation and feedback and opinions of each dancer. This piece was originally danced by dance majors at UCI: Cynthia Harada, Kat Huntley, Constance An, Michelle Camaya, and Olivia Eng. We found that when dancers are empowered as individuals they have the power to rejuvenate, inspire, corrupt, heal and improve themselves and audiences. The romantic ideal is that through communication and respect of self and other we may one day all live in peace.
Academia and the Professional Dancer
Mentor: Bonnie Homsey
Aspiring students seeking professional careers in the competitive realm of dance, employ contrasting approaches to achieve success. My research and observations at various dance academies in New York City during the summer of 2003, namely STEPS studios, American Ballet Theater, Mark Morris, and Jose Limon studios provide valuable insight to training approaches of major dance conservatories versus dance programs in a university such as UCI. In New York, particularly for the more prevalently contemporary companies, the most employable individuals are those with training in both ballet and modern dance. Based on my observations within UCIs Dance Department, I concluded that for the most part, individuals primarily trained in classical ballet first encounter recurrent performance opportunities or even training in modern dance, at the University. If generally more than 65% of dancers in contemporary companies around New York are university graduates and most university graduates in dance programs around the country have a higher success rate in the professional realm of modern or contemporary dance as opposed to classical ballet, then it is only logical that universities provide its students with a foundation that ultimately makes its dancers employable for modern or contemporary companies. Dance students in the university, through its wide-ranging programs involving academics as well as technique classes, develop analytical skills necessary for the more conceptual approaches to contemporary choreography. In conjunction with the rigid training common to big dance conservatories, a well-rounded experience such as that of a university graduate produces a powerful professional dancer.
Mentor: Alice Fahs
In the late nineteenth century more than a dozen Spanish newspapers were founded in California. These journalistic pieces served to inform the Spanish community on local and international news. However, these newspapers did more than inform and report. They helped bridge the class stratification that existed between the Ranchero elite and lower class Mexicans by reporting on problems of discrimination, injustice, and most importantly by advocating cultural awareness and pride. All together, these newspapers offer insight into the social and political circumstances that led to the forming of this relationship. Most interesting is the evolution of the relationship between the upper and lower class Mexicans that is seen through the years in the various newspapers. This research adds to the small, but growing, work done on Mexican-Americans in the late 1800s by looking at both the upper and lower class perspectives through the different newspapers that were established by the two groups. By doing so, I will illustrate how these two groups, once distinctly separated by class, found solidarity through the written press.
Distribution of the GABAC r 3 Subunit in the Bovine CNS
Mentors: Ataúlfo Martinez-Torres & Ricardo Miledi
g -Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the vertebrate central nervous system. There are three types of GABA receptors, known as GABAA, GABAB, and GABAC. GABAA and GABAC receptors belong to the family of ionotropic receptors and allow the passage of chloride ions into the cell. The negative chloride ion flux into the neuron causes a hyperpolarized state, which inhibits action potentials. The GABAC receptor was discovered in the vertebrate retina. However, there may be other areas of the brain where the GABAC receptor is expressed. GABAC receptors are oligohomomeric receptors made up by at least three types of subunits (r 1, r 2, and r 3) encoded by different genes. The goal of our study is to determine which specific areas of the brain contain the r 3 subunit and identify any potential isoforms of the receptor due to alternative splicing, by reverse transcribing mRNA extracted from specific bovine central nervous system areas. So far, our results indicate that the r 3 subunit is present in the retina and may also be present in cingulate gyrus and cortex.
Heritability of Physiological Traits Associated With Resource Allocation in the Evolution of Dioecy in Schiedea adamantis
Mentors: Ann Sakai & Stephen Weller
Gynodioecy may be a transient stage in the evolution of dioecy in S. adamantis, a Hawaiian endemic with substantial differentiation in male and female function between females and hermaphrodites. Differences in physiological traits between genders affecting resource acquisition may be important in the evolution of dioecy. In this study, I measured trait means, narrow sense heritabilities, and genetic correlations of physiological traits. Females and hermaphrodites did not differ in instantaneous measurements of photosynthetic rate (A), stomatal conductance (g), and water-use efficiency (A/g), suggesting they have an equal ability to acquire resources. Females showed significant heritability in stomatal conductance. Both sexes showed significant heritability in the morphological traits of stem number and inflorescence number, suggesting the possibility for further evolution of these traits. Although many physiological traits were correlated within the sexes, there were no genetic correlations of physiological traits between the sexes. These results suggest that genetic correlations between sexes will neither impede nor help in the further separation of sexes.
The Effect of Background Strain in Mouse Models of Huntingtons Disease
Mentor: Oswald Steward
Excitotoxic cell death occurs when glutamate and/or related excitatory amino acids activate glutamate receptors and cause repetitive neuronal excitation leading eventually to cell death. Inbred strains of mice have different vulnerabilities to excitotoxic cell death in brain areas including striatum, cortex and hippocampus, depending on genetic background. Excitotoxicity is thought to play a large role in the selective neurodegeneration in Huntingtons disease (HD), a hereditary disorder that is due to a CAG expansion in the HD gene. We used the CAG140 knock-in mouse model of HD to evaluate the role of strain background in an animal model of HD. We bred the CAG140 mutation into two different background strains, the FVB, which is vulnerable to excitotoxic cell death and the C57BL/6, which is resistant to excitotoxic cell death. We evaluated the two new mouse lines for changes in neuropathology and behavioral phenotype. The excitotoxin quinolinic acid was injected into the right striatum at three different ages, 4 weeks, 8 weeks, and 16 weeks. Results are pending, but we hypothesize that the CAG140 mice with the FVB background will have significantly more cell death than the mice with a C57BL/6 background, and also that younger mice will have significantly more cell death than older mice. If we find that the background strain affects the transgene, then the background strain will need to become a more important consideration when new transgenic models are created.
Transgenic Expression of Borrelia Species RecA in the Heterologous E. Coli System
Mentor: Alan Barbour
The recA gene is one of the 25 identified genes in Escherichia coli (E. coli) that promote homologous recombination for DNA repair. This protein is highly conserved. However, sequencing of Borrelia hermsii recA revealed a glutamine for lysine substitution at position 164 of the deduced protein sequence. Complementation studies performed in recA- E. coli with B. hermsii recA have shown that B. hermsii recA has a reduced ability to compliment DNA repair defects of recA- E. coli cells. The object of our experiment is to determine if this glutamine for lysine substitution is responsible for the observed weakness. Using site directed mutagenesis, we modified B. hermsii recA to produce a lysine for glutamine substitution. We then performed complementation experiments in recA-E. coli to assess the survival of cells in the presence of UV radiation and mitomycine C. The survival of B. hermsii modified with that of B. hermsii wild-type recA and additional Borrelia species previously studied, B. burgdorferi, were characterized.
Development of an Asymmetric Catalysis for the Intramolecular Acyl Nitroso Diels-Alder Reaction
Mentor: Kenneth Shea
Enantiomeric control in acyl nitroso cycloadditions has been achieved with varying degrees of success by incorporating chiral auxiliaries, most often carbohydrates, in the acyl nitroso precursor. In this project, chiral salen ruthenium (II) complexes are being synthesized and evaluated for their efficiency as asymmetric catalysts for the Diels-Alder cycloaddition of acyl nitroso dienophiles. To induce asymmetry in the cycloaddition reaction, the catalyst must not only oxidize the hydroxamic acid precursor to the intermediate acyl nitroso but it must also mediate the subsequent cycloaddition step. Earlier work by Whitting et al. reported successful catalytic oxidation of t-butyl-N-hydroxy carbonate with RhCl2 (PPh3)3 using t-butyl peroxide as the stoichiometric oxidant. When the oxidation was carried out in the presence of 1,3-cyclohexadiene, the 4+2 cycloaddition product was obtained in 69% yield. The mechanism is unknown but an intermediate ruthenium oxo species was proposed as the metal oxidant. We are synthesizing precursors to chiral ruthenium oxo species. These complexes will be evaluated for their ability to serve as catalysts for the oxidation of hydroxamic acids and for their ability to influence the enantioselectivity of the subsequent Diels-Alder cycloaddition.
Optimizing the Reconstruction of Coronary Vessels with Parallel Simulated Annealing Schemes
Mentor: Stephen Jenks
Simulating the coronary networks of the heart on a computer may be a viable and non-invasive approach to better understand the human heart and how it is affected by bodily disorder or disease. However, reconstructing the coronary vessels in silico is a complex and computationally intensive problem. Each step in the reconstruction process requires a number of energy-minimization solutions that conform to real physical properties. A single-processor prototype for the reconstruction of the coronary network has already been very much developed, though the problem is so rigorous that it takes weeks to compute. The goal of this research project is to optimize the computationally-intensive components of the reconstruction process by distributing the workload to many computers and by implementing more efficient energy-minimization algorithms. Specifically, we parallelize the heuristic-based perturbation and cost functions with hope to decrease the time it takes to reconstruct the large epicardial arterial vessels. Different parallel schemes for energy-minimization are also explored.
Ipsilateral and Contralateral Transfer of Motor Learning
Mentor: Charles Wright
This experiment compared ipsilateral (to the same side of the body) and contralateral (to the opposite side of the body) transfer of learning for finger and arm movements. It was hypothesized that ipsilateral transfer would be greater than contralateral transfer. Each of 36 participants learned a sequence of spatial movements (tapping on a keyboard or pointing on a screen) in one of six different conditions, resulting from the factorial combination of two starting hands and three transfer effectors: contralateral hand, contralateral arm, and ipsilateral arm. Results showed that there was an advantage of transfer within the same side of the body than to the other side of the body.
Collage: Music, Cinema and Plastic Arts
Mentor: Fred Moten
In the creation of art, (music, cinema and plastic) collage, montage, or assemblage emerges throughout the different mediums as a basis for the act of creation. The process by which artworks are created within different mediums is essentially the same, finding common ground upon the acts performed--principally an aesthetic of cutting and pasting. Yet, through the practice of cutting and pasting what emerges is an art that continuously reveals the process by which it is made. Through a film, painting, or piece of music, political action is undertaken through the cut. Cutting is always a political act--cutting up images, cutting up music--breaking up pieces and creating your own voice through other cultural products makes way for the political voice by means of artistic practice.
Effects of a Gurney Flap on a Low Reynolds Number Airfoil
Mentor: John LaRue
A Gurney flap is a rectangular strip attached at the trailing edge of an airfoil used to increase the coefficient of lift at the given angle of attack as well as the maximum coefficient of lift. It also increases the drag of the given airfoil. Although previous studies have shown that the use of a Gurney flap is beneficial despite the penalty of increased drag, they do not illustrate the effects on an airfoil specifically designed to give high lift at low Reynolds number. Selig 1210 was chosen as the representative high lift low speed airfoil. Various configurations were achieved by combination of mounting angles, 10, 30, 45, 60, and 90 degrees, and height of Gurney flaps, 1, 2, and 3% of chord. Various combinations were used to find the optimal setting of a Gurney flap on the low Reynolds number airfoil. Lift and drag coefficients for various configurations were measured experimentally in the wind tunnel. Expected results will show increase in both lift and drag as well as increase in lift-to-drag ratio. Expected results will be similar to previous studies despite low Reynolds number. Such results may be used to design a plane specifically geared to have high lift such as a cargo airplane or higher capacity commercial planes.
Construction of Controllable Gene Expression Vector
Mentor: Guey-Chuen Perng
Herpes Simplex Virus Type I (HSV-1) is a neurotropic DNA virus with many favorable properties as a gene therapy vector. The first noticeable property of HSV-1 is its ability to establish latent infection in sensory neurons of its host. With a broad host cell range, HSV-1 is highly infectious and thus can act as an efficient vehicle for the delivery of foreign genes to cells. Secondly, the HSV-1 viral genome is large (~152 kilo base pairs); as a result, several viral genes are dispensable without affecting the replication ability of HSV-1 in vitro. In our area of study, we exploit features of the latency active promoter complex to achieve a controllable, stable foreign gene expression in the nervous system. The first part of the project required characterizing a previously generated HSV-1 Doxycycline-inducible vector system by Western and Northern blot. A leakage gene expression was detected; therefore, a new construct of the tight regulated HSV-1 was created. In order to carry out the homologous recombination of the new HSV-1, we cloned the key tight regulated and inducible elements into the proper plasmid. In RS cells, co-transfection of the newly-constructed plasmid with infectious prototype viral DNA containing Tet-on elements was performed. Currently, we are screening the viral recombinants by picking and growing viral plaques in RS cells, isolating and treating viral DNA with restriction enzymes, and identifying the desired viral recombinants by probing with a radiolabel-specific gene probe. When the desired tight inducible HSV-1 vector system is found, testing of the construct in tissue culture will follow to see if transcription levels are inducible by Doxycycline. In doing so, we hope that our study can eventually provide a valuable tool for gene function study and lead to the development of an effective and manageable gene therapy vector.
Determining the Metallicity of a Globular Cluster
Mentor: Tammy Ann Smecker-Hane
In my research, I will use Sarajedini's technique determine the metallicity and reddening of a globular cluster by measuring the shape of the red giant branch in color magnitude diagrams. I will image the clusters using the ST9 charged-coupled device (CCD) camera attached to the UCI 24-inch Robotic Telescope and produce digital images in two wavelength bands (B and V). From the images of the Messier 3 globular cluster, I will use a suite of software called DAOPHOT to photometer the stars. In calibrating my measurements I will be observing Stetson and Landolt photometric standard stars, which will involve taking data at different airmasses and for stars having different colors, to produce a robust calibration to the standard B and V bands. I will also attempt to integrate deeper on the cluster to produce images that extend to much fainter magnitudes so that I can determine the cluster's age by comparing the shape of the main-sequence turnoff region to theoretical stellar evolution models produced by the Padova group (Girardi, et al., 2000, Astron. & Astrophys. Supplements, 141, 371). The purpose of this experiment is to calibrate the camera and test its accuracy to see how well we can analyze a0 globular star cluster using the UCI Observatory.
Sputtering of High Permeability Thin Films
Mentors: John LaRue & Richard Nelson
Sputtering, which is performed in a vacuum chamber, is one method of thin film deposition. The atoms stick to a substrate in the vacuum chamber and a thin film of the target material nucleates a thin layer and the film thickness increases as more material is sputtered. Using metal alloys with specific concentrations of the metals can create high magnetic permeability thin films. It is the thesis of this project that a sintering method for the fabrication of sputtering targets can be developed in order to optimize the composition of the alloy. The sputtering target is created using the Thermal Press already developed by another student. Iterative experiments have been performed to optimize the pressure and temperature for the sintering process. After the fabrication of the sputtering target, the target must be mounted in the sputtering machine. Methods for measuring the permeability will be examined. Low frequency measurements of the magnetic field in a solenoid before and after inserting the films into the solenoid can be performed. High frequency measurements will probably require the fabrication of a transmission line using the high permeability material.
Probit Analysis: The Likeliness of a Bank Surviving the Great Depression
Mentor: Gary Richardson
During the Great Depression (1929-1934), many banks failed after the collapse of the United States stock market. Since then, the Federal Bank assisted some of these banks by disbursing federal funds to them to prevent the economy from deteriorating; the Fed attempted to rescue the banks to avoid economic distress. However, with the constraints of its resources, the Fed was forced to choose between the banks that were likely to survive the recession and the ones that were not. By using the Probit model, a model that judges the effect of independent variables to a binary dependent variable, this paper analyzes the likeliness of a bank surviving in New York during the Great Depression. The results of this paper could provide some useful insight on what the Federal Bank of the U.S. used as a guideline to determine which banks they should aid and which banks they should not aid. This paper aims to provide an overview of the financial requirements that were expected by the Fed for banks to receive their governmental aid. In addition, this paper attempts to quantify the amount the Fed should grant to the banks, which were expected to survive.
The Salvaging Life: A Film About Vision, Identity, and Junk
Mentor: Fatimah Rony
Pulling items out of the trash and using them is often associated with the most marginal and desperate members of American society: homeless people. However, there are many people who salvage used and discarded items who would not categorize themselves as marginal and certainly not desperate. The names they have for themselves include "junker" or "picker," as well as businessman, lawyer, judge, husband, wife, or mother. The Salvaging Life is a documentary film that consists of interviews and footage of people demonstrating the process of salvaging in Salt Lake City, UT. I chose to film in Salt Lake City because I have personal connections with the "junkers" in that area and therefore had more access to not only the businesses but also the homes and personal lives of the people in the film. The documentary was shot on digital video over a two-week period and edited on a computer. The Salvaging Life explores the motivations for and the practice of salvaging used and discarded objects for use or sale. It shows that the reasons for collecting used items are very diversea desire to save earths resources, the need to make a living and provide for families, or simply an enjoyment of the "hunt" for unique and rare objects. The subjects of the film consider themselves a unique group because they dig through trash, but at the same time they reflect mainstream American aspirations to make money, raise families, acquire possessions, and have fun. As a documentary filmmaker, I have begun to learn the importance of counterbalancing films natural tendency to place groups of people on "display" with information that not only connects the subject with the viewer, but also scenes that uncover the relationship between the subject and the camera. Thus, the creation of the film has given me a learning experience not only about "junkers" but also the process of funding, filming and editing a documentary.
Prostitutes, Police and Politicians: The Subculture of Vice in Chicago, 1893-1912
Mentor: Alice Fahs
An examination of the reasons prostitution existed in the United States at the turn of the century uncovers multiple explanations including urban migration, industrialization, a new single young labor force and the rise in commercialism. In Chicago, an enormous underground culture of vice including gambling, drinking and prostitution allowed prostitution unprecedented prosperity during this time. This way of life allowed a wide variety of businesses to succeed in a time when there were large numbers of people struggling to make ends meet. Men, especially the politicians and the police, institutionalized prostitution thereby making it a lucrative business requiring protection from reformers anxious to maintain morality in United States culture. Chicago is the epitome of institutionalized vice in the United States in large part because of its geographic location and its national image which reflected the cross cultures of the entire country. Even as the people of Chicago felt that the government was not in business to legislate morality, government institutions profited from this underground economy. Reformers made unsuccessful attempts to persuade the government to shut down the Chicago brothels during the twenty years spanning the turn of the century. Only when the media excessively publicized the white slavery scare beginning in 1907 and ending at the start of the First World War, were reformers able to call enough attention to the vice districts of the First and other wards in Chicago to effectively shut down the subculture of prostitution.
Characterizing Demineralization of the Enamel Surface Using Optical Coherence Tomography
Mentor: Petra Wilder-Smith
Optical Coherence Tomography (OCT) is a rapidly developing imaging modality that generates high-resolution, cross-sectional images of internal microstructures in biological tissues, in situ and in real time. Previous studies have shown that OCT may serve as a modality for observing decay in extracted teeth; however, little is known about the optical effects of demineralization alone. Causes of demineralization include (1) gastro-intestinal reflux (2) carbonated beverages and (3) acidic foods. We hypothesize that OCT efficiently characterizes structural and chemical change on the enamel surface. The object of this investigation is to identify the capability of OCT for characterizing structural and chemical change resulting from demineralization of the human tooth, specifically the thickness of the enamel above the dentin layer, and changes in enamel mineralization, using OCT.
Self Esteem and Skin Color Among African American College Women
Mentor: Katherine Tate
The relationship between beauty and self-esteem in women has been a topic of research throughout the years. More recently, research has examined the correlation between perception of beauty and self-esteem with skin color. Past results conclude that African American women in general report higher levels of self-esteem and body satisfaction than their Latino and White counterparts. Additionally, those African American women with lighter skin tones have higher levels of self-esteem than those with darker skin. This study seeks to determine if a relationship between skin color and self-esteem actually exists. If so, is it true that African American college women with lighter skin color report more satisfaction with their physical appearance than those women who have darker skin? Based on a survey of African American women enrolled in an undergraduate degree program, my anticipated results are that there will be no difference between African American women with darker or lighter skin because women have come to terms with and accept their appearance as being beautiful. I argue that African American women have a different standard of beauty than Whites and Latinos do that allows them not to compare themselves to women belonging to different racial groups. I hypothesize that family and not the media or peers influences how African American college women feel about themselves. Although they are aware of media depictions of African American women and the so-called beauty standard placed on other races, they choose not to adhere to those standards and internalize positive attitudes from their families.
The Effects of Age, Stress Reactivity, and Gender on the Reinforcing Actions of Nicotine
Min Suk Jun
Mentor: James Belluzzi
It has been shown that rodents prefer a nicotine solution to water during early adolescence, while the opposite behavior is true during adulthood. In addition, reduced stress through postnatal handling may decrease nicotine use. Gender has also been shown to play a large role in the self-administration of nicotine. Female rats have exhibited higher sensitivity to the anxiolytic effects of nicotine and more motivation to obtain it. The intent of this study was to identify the effects of age, stress reactivity and gender on the rewarding effects of nicotine. Acetylaldehyde is present in significant quantities in tobacco and may enhance nicotines reinforcing effects. Thus, a mixture of nicotine and acetylaldehyde was used to create a drug solution that more closely mimics the chemical content of tobacco smoke. Adolescent (postnatal day 34) and adult (P90) rats were implanted with an I.V. catheter and offered a solution of nicotine (30 m g/kg/inj) and acetylaldehyde (16 m g/kg/inj) during daily two-hr self-administration sessions for five consecutive days. Females self-administered the drug solution significantly more than males. Stress reactivity differences did not produce significant differences in adolescent self-administration but did in adult animals. These findings provide evidence for a difference in self-administration between genders. Evidence for a difference in behavior based on stress reactivity is less concrete, but nevertheless present.
Prenatal Exposure to Manganese Alters the Effects of Methamphetamine in Rat Striatal Tissue
Mentor: Michael Kleinman
The present study attempts to summarize the effects of manganese (Mn) and methamphetamine (Meth) on rat striatal tissue and hypothesizes that prenatal exposure to Mn will exaggerate the changes caused by postnatal exposure to Meth. In order to investigate this issue, pregnant rats were exposed to inhalation Mn and the pups were then injected with Meth and sacrificed to extract the brain. Coronally sectioned striatal region of the brain tissue was micro-sliced and stained with hematoxylin and eosin (H&E) and luxol fast blue (LFB). H&E stained slides were initially analyzed for changes in the internal capsules, bundles of axons within the brain. Next, we used the LFB stain to determine if any changes are due to alterations within the myelin sheath. Results from the H&E stains indicate that there is a significant reduction in the internal capsules of the Pre-Mn group, an increase in the Post-Meth group, and a slight increase in the Pre-Mn & Post-Meth group. Data from LFB stained slides reveal that there is a significant reduction in the Pre-Mn group, a slight increase in the Post-Meth group, and a significant increase in the Pre-Mn & Post-Meth group. Taken together we propose that prenatal exposure to Mn causes histological changes within the internal capsules of the striatum and combined exposure to Mn and Meth increases the affects of Meth alone. These conclusions are important because industrial exposure to Mn and continuous abuse of Meth are widespread problems that must be addressed to eliminate unnecessary exposure to these toxins.
MEMS Assisted Detection of Spontaneous Activity In Prematurely Born Infants
Mentor: Andrei Shkel
Premature infants, born early during the last trimester of pregnancy, weigh no more than 2000 grams and have very under-developed bones and muscles. Recent studies have shown that manual exercise to preterm babies enhances their growth and development, both in weight and bone strength, as compared to babies that dont receive the exercise. This passive flexing of the joints is performed in 5-15 minute sessions daily for a time span ranging up to four weeks. However, doctors doubt these sessions exclusively account for the babies improved health. The theory is the assisted exercise induces more spontaneous activity throughout the entire day, thereby building stronger muscles and bone structure. Efforts to monitor these movements are not widespread due to their invasive nature, space requirement and room for human error (e.g., videotaping, lasers, etc.). The goal of this project is to explore opportunities in MEMS technology to develop a micro-scale sensor that can detect and accurately measure infant movement via wireless interface. Micro-Electro-Mechanical Systems (MEMS) is an emerging technology that encompasses various devices, such as gyroscopes and accelerometers, with the latter used to measure acceleration in many civilian and military applications. During the initial phase of this project, our focus is to simulate preterm infant movement and measure the motion with an accelerometer. Preliminary testing indicates that the accelerometer-computer interface has an accuracy equivalent to a human observer. We hope that these results, coupled with continued research, will lead to more efficient methods of monitoring infant motility with the aid of MEMS.
Symmetry in Science and Philosophy
Mentor: Roger McWilliams
In this paper the role of symmetry in the practice of physics will be reviewed. Symmetry has motivated the direction of the development of physical theory, and has led to the prediction and discovery of important and fundamental physical phenomena. This presentation will further explore the logical and philosophical basis for this motivation, and discuss its justification and continued use.
Self-Recategorization of Euro-Americans and Its Effects on Prejudice and Racial Perceptions
Mentor: Peter Ditto
The Common Ingroup Identity Model (Tajfel & Turner 1979) is grounded in the social categorization perspective of intergroup behavior and has shown that how one identifies their own group membership determines in-group versus out-group members, which in turn affects the level of prejudice exhibited. Research has shown that recategorization to include a shared group identity extends favor to former out-group members while decategorization reduces favor toward former in-group members by emphasizing individual differences within the group (Dovidio, Kawakami & Gaertner, 2000). For the current research, a manipulation measure (dual/ethnic identity) was designed to combine both manipulations to maximize the reduction of categorization. A convenience sample of 114 high school students, from a predominantly White area with reported hate crime activity among the youth, was targeted for the research. The experiment was designed to allow for within and between group comparisons by embedding the identity measure within the survey. Control group members were primed for a single identity while the experimental group received the dual/ethnic identity measure. The experiment included photo perception as the first and last tasks. It also included a variety of established prejudice and social dominance measures before and after the manipulation. To determine if their prejudice may be group specific, subjects were asked about both Asians and Hispanics. Initial analysis has shown high measures of prejudice among students. As expected, exhibited prejudice appears to be group specific: against Hispanics with higher measures of acceptance of Asians.
Policewomen in the Media: 1900-1950
Jee Soo Kim
Mentor: Paul Jesilow
"Policewoman" as an occupation did not exist before the twentieth century. The entry of women into the field of police work accompanied a more general involvement of activism by females in the late 1800s and early 1900s. American middle-class women of this period sought the reformation of numerous social problems that were the result of the Industrial Revolution in the United States. In police work, women saw an opportunity to use their gender-specific niche and expand their role in society. Analysis of print media of the time revealed that women were very successful at defining a preventive, nurturing, and motherly image of themselves within the police department. However, they were not as successful in their attempts to make a dramatic difference in the way society valued women.
Efficacy of Drug Treatment Programs on Women: The Effect of Proposition 36
Mentor: John Dombrink
The efficacy of the Substance Abuse and Crime Prevention Act (SACPA), passed as Proposition 36, may be determined by considering the substantial improvements in treatment methods and the acknowledgment of a diverse set of challenges that need to be addressed in order to promote the recovery of women drug users. Research indicates that the barriers confronted by married and single mothers participating in residential treatment programs are overcome more efficiently then of those in outpatient treatment facilities. By allowing drug-addicted females to disclose their reasons for drug use, and express concerns and expectations in a private facility, women dedicate themselves to the task of recovery. However, not much research currently exists on the types of obstacles faced by women in court-mandated and voluntary treatment programs. The objective of this research was to examine the efficacy of drug intervention programs on women in single-gendered and mixed treatment programs. Women pooled from local treatment sites conveyed long-term success in an all-female environment and a mixed-gender facility utilizing various methods of treatment. This study reveals that special care and attention provided to women in gender-specific modalities increases the rate of recovery and decreases the tendency to relapse.
The Success and Failure of African Democracies
Mentor: Anthony McGann
Current theories do not explain the success and failure of democracy in Africa since the early 1990s. Theorists often cite low-income levels, high degrees of ethnic fragmentation and high levels of corruption as reasons for democratic failure. However, these theories do not explain the relative success of democratization in this region, as many countries with exactly the characteristics that should lead to failure, have succeeded in establishing a democratic government and staying stable for approximately a decade. On the other hand, countries without the characteristics that should lead to failure, have failed in recent years. This study attempts to explain why democracy succeeds or fails in Africa by looking at different levels of power sharing in the government of each country. Countries were classified based mainly on Freedom Houses Freedom in the World Country Ratings. The successful democracies are Benin, Botswana, Ghana, Mali, Namibia, Senegal, South Africa and Tanzania. The failed democracies are Congo (Brazzaville), The Gambia, Kenya, Zambia and Zimbabwe. These countries were compared based on the type of electoral system, level of indebtedness and whether or not the country has a single party majority. I used a Boolean variable approach to analyze relationships between the dependent and independent variables. While these variables cannot fully explain the success and failure of democracy in Africa, the results indicate that the successful democracies have higher levels of power sharing in their governments.
Newly Generated Dentate Granule Cells of Epileptic Rats Exhibit Elongated Hilar Basal Dendrites
Mentor: Charles Ribak
Numerous studies have shown that neurogenesis occurs in the dentate gyrus of the adult, and recent evidence suggests these newly generated granule cells integrate into pre-existing hippocampal circuitry. To determine whether hilar basal dendrites of epileptic rats were longer than those in the control, we used the immunocytochemical method for doublecortin to stain newly generated granule cells and their associated dendritic processes. Here we show that indeed hilar basal dendrites found in the pilocarpine-induced model of temporal lobe epilepsy are two times as long as those found in control rats. We also show that there is a correlation between the location of the granule cell and the length of the dendrite into the hilus. This study also confirms the existence of growth cones on immature newly generated granule cells in the dentate gyrus of adult rodents.
Navigation System for Virtual Reality Visualization of Large-Scale Astronomical Datasets
Mentor: Joerg Meyer
Visualization of large-scale datasets requires new approaches to data processing, hierarchical representation, and navigational techniques. We introduce an initial stage in design of an interactive immersive virtual reality system allowing rapid high-resolution rendering of large scale datasets including, but not limited to, astronomical, biomedical, and seismographic data. A prototype implementation of the system framework is applied to a 3-D model of the Solar System featuring an interactively controlled camera and time lapse. The spatial scaling issue, which is essential to the study due to specifics of sparse data processing, is addressed; a logarithm-based scaling method is introduced, and optimal scaling parameters for efficient representation of the Solar System are determined and used to run the space simulation. Techniques employed in the design of this system can potentially be used to build scalable, easily navigable and extensible models of entities such as stellar constellations, galaxies, and, ultimately, the known universe. The system can then become an intuitive astrophysical simulation tool, helpful in forming a completely new approach to such traditionally analytical applications as mission planning, control, and visualization of simulated space flights. These techniques will also be used to create a modular system that can be used to navigate large datasets in a virtual reality system at the California Institute for Telecommunications and Information Technology, Cal-(IT)2.
Exhibit In Celebration of 300th Anniversary of Saint Petersburg
Mentor: Dragan Kujundzic
May 2003 marks the 300th anniversary of the founding of Saint Petersburg, the capital of Russia from 1712-1918. Saint Petersburg is a unique city by its cultural, intellectual and historical treasures. Located at the crossroad of several cultures it has marked human history in an indelible way and has bequeathed invaluable treasures in all the areas of human activity: from religion to science, from architecture to theatre, and from politics to philosophy. In consideration of the special role of Saint Petersburg in the history of Russia--in all stages of its development as an international cultural, political, and research center, an exhibition would be created to celebrate Saint Petersburgs 300th anniversary, the history of people, who lived and worked here, and who have generated the spirit of Saint Petersburg. This exhibit will feature a PowerPoint presentation, which will unfold the history of Saint Petersburg, its most visited places, and other significant historical sites. Important pictures of this city will be enlarged and framed, and other pictures will be developed panoramically to show the beauty of Saint Petersburg. In addition, a special event will be organized to present this exhibition at UCI campus, followed by reception, and enhanced by discussion panel and student/faculty projects in relation to Saint Petersburg. This exhibit upon its opening will remain on permanent display in the Russian Program, HOB2, at UCI.
Effects of Nonyphenol on Retinoid Disruption in Developing X. Laevis Tadpoles
Mentor: David Gardiner
Recently, a high incidence of malformation has been associated with the declining amphibian population worldwide. A synthetic retinoid, TTNPB has been shown previously to cause malformation identical to that found in the field. Nonionic surfactants are often incorporated into pesticides sold and used and amphibians are therefore at high risk of exposure in shallow waters where there is little opportunity for diffusion. Nonylphenol (NP) is a very ubiquitous example of such a surfactant. Xenopus laevis was used as a model organism to assess the possible potentiation of the teratogenic effects of TTNPB by NP, the nonionic surfactant tested. We exposed X. laevis tadpoles to TTNPB with and without NP and compared the resulting deformities. We found that NP had an inhibitory effect on TTNPB-induced teratogenesis using the standard hind-limb assays. We also found that there was a dose-dependant decrease in survivorship over the duration of experimentation as the dose of TTNPB was increased and that this effect was enhanced in groups receiving TTNPB with 10 ppb NP.
Ionic Wind Velocity
Mentors: Derek Dunn-Rankin & Matthew Rickard
Through the use of ionic, or electric winds, tasks such as air purification through a rapid filtration of unwanted particles, drag reduction, and convective cooling can be undertaken, though with a simplistic design compared to fans. For the generation of an ionic wind, a device requires no moving parts and emits very low noise enabling facilitation in sensitive locations. The problem with an ionic wind device is its inability to produce a high velocity to be effective in any application. Data from past research shows that velocity peaks at 3 to 4 m/s--strong enough to be felt by human touch but not fast enough for use within previously mentioned applications. This study is to confirm the existence of a limitation on the velocity of the ionic wind and to understand the physical mechanism responsible. The design of a multistage tube device with integrated grounding points between sections has been attempted previously, however, very little increase in velocity was observed. The purpose of this study is to modify the multistage design by adding an exit nozzle and increasing the number of stages (from 3 to 15). Ground rings with both sharp and smooth edges to go inside the acrylic tubing used have been tested for a comparison of efficiency. Temperature versus time measurements were made to compare the sharp versus smooth shape and an optimum ground ring shape has been designed from the data. The device is currently being constructed and measurement strategies will include quantitative information on the velocity and pressure.
Misperceptions of Randomized Events
Mentor: Chuansheng Chen
Piagetian theory states that children eventually end at formal thinking; however, some adults cant get past their reasoning biases, but others can. Previous research has identified two types of misconceptions about random events among educated populations (e.g., college students and professionals): 1) gamblers fallacy labeled as Type I (Kahneman and Tversky, 1972); and 2) systematic bias fallacy labeled as Type II (Keren and Lewis, 1994). Little research has examined individual differences in those misconceptions. The present study was designed to examine (a) whether such misconceptions have consistent inter-individual differences and (b) if there are consistent individual differences, whether they are correlated with differences in beliefs and aptitudes. Data were collected from 101 college students (60% female) who completed a questionnaire and a math test including four questions about random events. Preliminary results showed that only 2% of the subjects answered all four questions correctly, whereas 48% did not answer any of the questions correctly. Type I bias (gamblers fallacy) was predominant with 90% of subjects making at least one Type I error. On average across the four questions, 10% of the subjects made Type II errors (systematic bias). The number of correct responses to the four randomization questions was positively associated with scores on the math test. Type I errors were negatively associated with SAT scores. Type II errors were too sporadic to allow for correlational analyses. Their associations with scales such as Belief in a Just World and Optimism did not reach significance level. Further analysis will indicate if the results of this study may have implications for theories of cognitive development, especially post-formal thinking.
Can Emergency Physicians Diagnose Appendicitis Using Bedside Ultrasound?
Mentors: John Christian Fox & Federico Vaca
The diagnosis of acute appendicitis is the most common abdominal surgical emergency seen in the ED. This diagnosis falls directly upon the emergency physician to make, yet it still remains a challenge because symptoms of appendicitis often resemble the symptoms of other abdominal complications. Despite the current technology, there is still a 10% negative appendectomy rate in men and a 30% negative appendectomy rate in women. While there are a variety of factors that contribute to perforation, the main factor is the time delay to diagnosis. With increasingly over-burdened emergency departments already relying heavily on radiology performed imaging studies, the time-savings of bedside ultrasound to obtain a diagnosis of appendicitis (BUSA) would be valuable in obtaining quick and accurate diagnosis in order to efficiently identify and treat the condition. The goal of this study is to determine whether or not emergency physicians can identify patients with acute appendicitis by using a bedside ultrasound instead of relying on professional radiology. This study will be the first of its kind to determine the effectiveness of a portable bedside ultrasound machine in diagnosing acute appendicitis.
Literature and History in Cervantes Mediterranean: The Possibility of an Annalistes Reading of Don Quixote
Mentors: Luis Aviles, Michelle Hamilton, Jane Newman & Daniel Schroeter
Cervantine studies in American institutions have generally dealt with the literary nature of Don Quixote and how the novel came to be, in fact, a novel. Only recently has Spanish history been a significant factor in Quixote criticism. The historical perspective of Cervantes most famous text still seems to limit itself, however, to economic factors: "how does the transformation of the Spanish gentry present itself in the psychosis of Don Quixote," texts like Carroll B. Johnsons Cervantes and the Material World (2000) and David Quints Cervantess Novel of Modern Times: A New Reading of Don Quixote (2003) seem to ask. What receives little attention, despite new tendencies toward consideration of historical problems and continuing interest in generic issues and the nature of the text is the matter of text itself. Throughout the Quixote, text is present everywhere, in the multiple layers of narration (from Arab historian to Morisco translator to Castillian editor), in the manuscripts left behind at inns and abandoned by madmen, in the hundreds of volumes of romance burned by the village priest from Don Quixotes library, and in the very textual references to preceding genres of epic and romance, from Spanish and even Arabic traditions. I intend to demonstrate how the instance of "text" within the text itself provides a more complete and coherent reflection of early modern Spanish society than strictly economic or generic considerations.
A Comparison of DAQ systems in the AMANDA Experiment
Mentor: Roger McWilliams
The Amanda experiment has recently undergone an upgrade of its data acquisition system. Both the newer TWR system and the older Muon-DAQ system are currently connected to the detector. The purpose of this analysis is to evaluate the TWR system in comparison to the Muon-DAQ system and show whether the TWR system is an improvement. Monte Carlo simulations will be run to directly compare the reconstructed angle of each system with the generated angle in Monte Carlo. However, since Monte Carlo results are not as trustworthy as those of actual data, we would like to find the angular resolution of the detector using data. We used some statistical devices to attempt to estimate the actual angular resolution of the detector. In order to better understand our results these methods were used on a Monte Carlo file, so that we could compare the true angular resolution with our estimations. I will discuss some failings of this method and suggest possible improvements.
A Preliminary Study of the Properties of the LIM-Only Protein, LMO-4
Mentor: Bogi Andersen
LIM-only proteins (LMOs) are nuclear proteins that are involved in transcriptional regulation. Two of the three LMOs that were initially discovered (LMO-1 and LMO-2) are oncogenic; their overexpression in lymphocytes leads to acute lymphocytic leukemia. Previous studies show that the fourth member of this gene family, LMO-4, is highly expressed in breast cancer. However, it remains to be tested whether LMO-4, like two of its family relatives, is an oncoprotein. We predict that its overexpression leads to the activation of target genes associated with cellular proliferation, thus providing support towards its classification as a tumor promoting protein.
In this experiment, we created an inducible LMO-4 cell-line in human MCF-7 breast cancer cells. We tested the various properties of LMO-4 in regards to cellular proliferation in addition to identifying potential target genes. In contrast to what we believed, cellular proliferation and colonization assays showed little difference between LMO-4 induced and non-induced cells. Utilizing microarray analysis, we found that expressing LMO-4 correlated with its binding to many developmental genes, and interestingly, to various apoptotic genes. We were able to validate BMP-7 and IGFBP-5, both involved in development, as being potential target genes for LMO-4. In addition, we found that LMO-4 expression induced apoptosis, implicating it apoptotic processes. Thus, we believe LMO-4 plays a role in regulating development and apoptosis.
Mapping the Essential Bipartite Nuclear Localization Signal Domain of UOL Protein
Mentor: Guey-Chuen Perng
The organelle localization of proteins is an indicator of the functions of a protein. During the course of herpes simplex virus type 1 (HSV-1) infection, viral proteins shuttle in and out of the cell organelles, such as the nucleus, playing a crucial regulatory role in infected cells. HSV-1 viral genome encodes more than 80 known genes. For a protein to be spotted or localized in the nucleus organelle, a nuclear localization signal sequence (NLS), is required to fulfill the task. UOL, a newly identified gene from HSV-1 viral genome, contains two bipartite NLS in which my goal is to check whether the NLS in the UOL protein are functional. If it is functional, then I will further characterize which one of the two NLS is essential for the UOL protein in targeting the nucleus. Preliminary results, using an indicator gene fused to UOL, indicated that the NLS in UOL protein is functional in transient transfected cells. I continued onto mapping the NLS domain. In this process I have designed five sets of overlapping PCR primers attached with universal restriction enzyme sites, EcoRI and BamHI at 5 and 3 ends respectively, to facilitate directional cloning. The amplified PCR fragments were then fused to the RFP gene, an indictor gene if expression properly a visible red signal will be seen. In my research progress so far, I have obtained two sets of fusion clones. While I am continuing on screening the other three sets of fusion RFP clones, I am currently performing the transient transfection assays to check for the organelle localization of RFP signal from those two newly acquired clones.
Functional Analysis and Regulation of Borrelia burgdorferi Thymidylate Synthase
Mentor: Alan Barbour
The thymidylate synthase enzyme catalyzes the conversion of dUMP to dTMP, a precursor to one of the four nucleic acid nucleotides. Two classes of thymidylate synthase exist (Myllykallio et al., 2002) and they include the thyA class which has the thymidylate synthase catalytic activity and the thyX class which is analogous to the thyA class. The thyX class is found widely but sporadically in many organisms including microbial species that lack thyA. Borrelia burgdorferi, the spirochetal pathogen that causes Lyme disease, does not have the thymidylate synthase thyA but it contains the thyA analog, the thyX, with unknown function. In our study, we want to know if B. burgdorferi thyX encodes a protein that has the thymidylate synthase catalytic activity. We are also interested in whether the gene expression of B. burgdorferi thyX is differentially regulated according to environmental conditions, specifically temperature. Northern and Real-Time PCR analyses showed that temperature shift does not differentially regulated thyX gene expression. We also found that the thyX is separately transcribed from upstream genes on the linear plasmid lp54 in B. burgdorferi. We investigated the function of thyX by a complementation experiment and an in vitro enzymatic assay using purified ThyX proteins. Results from the complementation experiment indicated that the B. burgdorferi thyX cannot complement thyA mutant E. coli.
SAE Mini-Baja and Formula
Mentor: Michael McCarthy
The word "engineering" is synonymous to "manufacturing," "process," "trade," "business," "commerce," and "production." The Engineering Project Development (EPD) series and thereby, the mini-baja and the formula project, are aimed to establish the processes and standards of a company; ultimately, leading to the manufacturing of a product viable for the market. The mini-baja project prompts engineering students to follow guidelines by SAE to construct a safe and durable vehicle and, in turn, compete against other schools. In essence, the UCI Baja Racing and Zot Racing team reconciles the real-world standards of SAE with hands-on application of fundamentals in the engineering curriculum. Such an accumulation of engineering values results in the formation of UCI Baja Racing and Zot Racing team and the production of each teams vehicles.
An Approach to Automate Distributed Parallel Code Generation for Messengers Using Dependency Graphs
Mentors: Lubomir Bic & Michael Dillencourt
The process of generating distributed parallel code from sequential code is a complex and time-consuming task. Such conversion requires sequential code to be mapped into a dependency graph, and from the dependency graph, distributed parallelized code must be manually generated. This project demonstrates the automation of distributed parallel code generation from annotated dependency graphs for MESSENGERS, an agent based distributed computing architecture. Automated code generation is done by creating a program that takes in an annotated dependency graph as input and outputs a collection of parallelized code. The program uses templates to represent dependency graphs of unknown dimensions, such as graphs of loops of variable length. Pattern matching techniques are used to minimize the size of the final thread layout by identifying common execution pattern. Two important evaluation characteristics for this program are correctness and efficiency of the generated code. Correctness can be evaluated by comparing the result of the execution of the generated distributed parallel code to the result of the execution of the sequential version. Efficiency is determined by the number of threads used in the parallelized version of the sequential code, and the length of each thread along the critical path of the program. It can be shown that the program generates both correct and efficient parallelized code. This program is expected to greatly assist future work of increasing the ease of programmability in MESSENGERS.
Does the Cholivergic Agonist Carbachol Regulate Neuronal AMPA Receptor Expression?
Mentor: Christine Gall
Neurotrophic factors play protective roles against neurological diseases in the brain. It is known that excitatory neurotransmission regulates the production of many neurotrophic factors, including the Brain-Derived Neurotrophic Factor (BDNF). BDNF is crucial for the survival of many populations of cells in the nervous system, and is regulated by the positive AMPA-type glutamate receptor modulators ampakines. Recent studies have shown that ampakines transiently increase BDNF expression in the brain; the ampakine-induced increase in BDNF mRNA expression peaks at 6 hr and then declines to normal levels by 48 hr of exposure to the drug. Ampakines have also been shown to decrease glutamate receptor expression. The present study will determine if it is a specific ampakine property to down regulate glutamate receptor expression, or if these results are due to a general increase in excitatory neurotransmission, regardless of the mechanism of induction. This study builds upon earlier ampakine experiments using the acetylcholine receptor agonist carbachol as the operative drug. The effects of carbachol on glutamate receptor expression will be compared to those of ampakines to guide our understanding of the actual causal relationship of ampakines on these neurofunctional properties.
Autism and the Effect on Ethnicity
Mentor: Kathryn Osann
Autism is a developmental disability characterized by delays in verbal and non-verbal communication, deficits in social interaction, and the presence of unusual stereotypic and repetitive behaviors. Autism in California has increased 273 percent from 1987 through 1998. The cause of autism is unknown, but it is believed to be largely genetic in origin, possibly reflecting the influence of as many as 10 different genes. Evidence suggests that autism affects all ethnic groups equally. In order to address this question, we obtained data from the California Dept of Education (DOE) on children receiving services for autism in Orange County. Using the ethnic distribution of births Orange County births for 1989-1999, we estimated what proportion of children born in 1989-1995 and identified by the DOE should belong to each ethnic group. We then compared the expected number to the actual observed. In 2002, 1000 children born in 1995-1999 were identified from the DOE data for Orange County. In this group were 604 Caucasians, 192 Hispanics, 21 African Americans, and 181 Asian Pacific Islanders. Based on the ethnic distribution of births in Orange County, we estimated that the expected number of children identified in the school system for each ethnic group is: 381 Caucasians, 483 Hispanics, 15 African Americans, and 122 Asian Pacific Islanders. The observed to expected ratio indicates that there are more Caucasians and Asian Pacific Islanders (O/E = 1.6 and 1.5 respectively) and fewer Hispanics (O/E = 0.4) receiving services in the schools for autism than expected.
The Shaping of Street-Level Police Discretion in Drug Law Enforcement
Mentor: John Dombrink
There is little room, if any, to doubt that discretion exists in police work. Yet, just how that discretion is shaped remains unclear. Studies have looked at organizational, neighborhood, and situational variables as well as officer characteristics as determinants of police discretion (Brooks, 2001). In doing so, many have scrutinized police discretion in specific contexts, such as domestic violence and sexual assault cases. The purpose of this study was to examine the factors shaping police discretion of patrol officers in drug law enforcement and determine whether they are limited to drug offenses. There was an expectation that several exclusive variables would emerge, most notably Californias Substance Abuse and Crime Prevention Act (SACPA), or Proposition 36. Officers from two police departments were interviewed, and the findings indicate that factors affecting discretion in drug law enforcement include the status of the offender (whether a recreational user, an addict, or a seller), the type and amount of drugs involved, and the offenders potential as an informant. The severity of the offense, the demeanor, attitude, and criminal history of the offender, and the officers experience emerged as influential variables in any given situation. Contrary to initial expectations, Proposition 36 did not appear to impact police discretion. What the findings do show, however, is that officers view Proposition 36 as a product of the governments failure to recognize the difficulties of drug law enforcement. Officers exhibited apathy and alienation toward lawmakers, revealing the widening gap between law enforcement and policy that this study hopes to help rectify.
Isolation of HSV-1 Small RNA Interference Molecules in Latently Infected Rabbit TG
Mentor: Guey-Chuen Perng
The herpes simplex virus type I (HSV-1) becomes dormant once infecting its host in sensory neurons of the trigeminal ganglia (TG). However, how HSV-1 establishes life-long latency is yet to be understood. Recently, studies have shown all organisms have some type of counteractive mechanism towards its hosts immune system. Small RNA interference molecule (RNAi) is one such mechanism. RNAi, a homology-based silencing system, introduces double-stranded RNA into a cell resulting in targeted silencing of gene expression. During HSV neuronal latency, the major gene actively transcribing is the latency associated transcript (LAT) gene. Thus, LAT is the distinct feature of HSV neuronal latency. RNAi is expected to be present in HSV latently infected animal TGs. By isolating and studying RNAi, we may gain better understanding of how HSV-1 remains latent in humans by studying immune competent hosts such as mice. We first tested our theory in HSV infected culture and total RNA was extracted from cultured rabbit skin (RS) and monkey kidney (CV-1) cells. The extracted RNA was separated by running them on 3% agarose-formaldehyde gel electrophoresis and transferred onto a nylon membrane via Northern capillary method. The membrane was dried, UV-crosslinked, and hybridized by a P-32 isotope HSV LAT DNA fragment. Probed RNA could then be visualized by autoradiography. Results showed the presence of small RNA molecules in infected cells and this suggested that isolation of RNAi was feasible in latently infected neurons.
Testing the Failure-to-Engage Hypothesis of Task Switching
Mentor: Scott Brown
The ability to switch from one task set to another task set quickly allows people to interact with the environment around them properly. Previous work (De Jong, 2000) has argued that task set switching occurs in two discrete manners: endogenously and exogenously. Endogenous switching occurs when subjects completely prepare for a new task before being required to perform the task. Exogenous task switching is when there is a "failure-to-engage" or a failure to prepare for the new task before the task-relevant stimulus appears. However, intuition tells us that task switching might not be so discrete since partial task set retrieval might occur before the stimulus appears. Therefore, the goal of this study is to test the "failure-to-engage" hypothesis by showing that changing the stimulus to response time and the trial type (non-switch/switch) will vary the reaction time distributions in a manner that is not consistent with the binary distribution proposed by De Jong, according to a mathematical theorem proposed by Falmagne (1968). The two tasks are to respond whether a letter is a consonant or a vowel and whether a number is odd or even using a PASCAL program that measures reaction time (RT) and error rates. Participants switch to the other task after every second consecutive trial. The data are currently still being collected but preliminary analysis of the RT distributions seems to indicate that the distribution is not binary as the "failure-to-engage" hypothesis predicts.
Assessment of Thermal Injury to Rabbit Nasal Septal Cartilage Expressing a Regenerative Response to Nd: YAG (l = 1.32 mm) Laser Irradiation
Mentors: David Gardiner & Brian Wong
Laser reshaping of cartilage in surgical procedures often results in thermal damage, leading to thermal necrosis or apoptosis of chondrocytes. However, previous studies have identified regenerating chondrocytes on the periphery of the laser irradiated regions in hyaline cartilage. The focus of this study was to identify the extent of thermal injury in areas where regeneration was previously observed in laser irradiated cartilage tissue. In this investigation, ex-vivo cartilage specimens were irradiated using an Nd:YAG (l = 1.32 m m) laser with combinations of time (4, 6, and 8 sec) and power (4,6, and 8 watts) settings. Irradiated specimens were placed in tissue culture with media containing 5-Bromo-2-deoxyuridine (BrdU), an organic label that is incorporated into the DNA of dividing cells. After a period of 2 weeks, the specimens response to photo-thermal injury was evaluated by a Live/Dead® cell viability assay using confocal microscopy. To identify areas of regeneration, a fluorescent antibody specific for BrdU was used to label cells that had divided; staining by this antibody was then visualized using confocal microscopy. The cell viability assay identified dead tissue within and immediately around the laser spot. Moving away from the center of the laser spot, a transition zone containing a mixed population of apoptotic cells and normal cells was found. Proliferating chondrocytes were also found in this region, forming a well-defined concentric ring surrounding the dead tissue. Additionally, this study found that cellular injury positively correlated with regenerative response within the laser parameters used.
Exchanged-Biased Magnetic Films
Mentor: Herbert Hopster
Metallic thin films possess unique magnetic properties, which is absent in their bulkier form. Through studying the hysteresis curves, which records the change of the magnetization of the sample with a changing external magnetic field, it is observed that the samples have different values of magnetization. These values depend on the change of the external magnetic field, and reach extreme values at the saturation points. The focus of this project is exchanged-biased magnetic films. When ferromagnetic ultra-thin films on the nano-scale are in contact with antiferromagnetic film, the properties of the ferromagnet can be greatly altered due to magnetic interface coupling. Exchange bias means that the antiferromagnetic film imposes a preferred magnetization direction on the ferromagnet. In this project we deposit ultra-thin (thickness on the order of 10 nm) films of different materials to produce exchange-coulpled bi-layers of Fe and Mn. The sample preparation is done under ultra-high vacuum (UHV) conditions in the 10-10 Torr range. Materials are evaporated from high-purity electron beam evaporation sources. The magnetic properties are investigated ex-situ by magneto-optical Kerr effect (MOKE) measurements. Temperature dependent hysteresis curves look for a difference in the hysteresis curve of the ferromagnetic layer (Fe) due to the magnetic ordering of the antiferromagnetic (Mn) layer.
Crystallization and Structure of Calretinin
Mentor: Brian Edmonds
Dynamic Light Scattering was used to test the purity of a calretinin sample by comparing the mass obtained from the procedure and that from calculation. This preliminary result suggests the possibility of the formation of either a dimer or a tetramer. Recent determinations of purity using both denaturing and non-denaturing gels have suggested that some dimer is present in solution. Conditions using DTT as a reducing agent have been employed to keep a very high concentration of homogeneous monomer in crystallization setups. We have recently obtained diffraction patterns from crystals of calretinin. We are currently working to improve these crystals to obtain an atomic resolution structure of calretinin in the Ca2+-free conformation.
The Reduction of Dinitrogen by Tris(tetramethylcyclopentadienyl) Lanthanide Complexes and Potassium
Mentors: William Evans & David S. Lee
For many years, dinitrogen reduction has not been approached using lanthanide metals because these elements were thought not to have the appropriate orbitals to bind dinitrogen. Interestingly, the first lanthanide dinitrogen complex, [(C5Me5)2Sm]2N2, was discovered through the use of a soluble molecular divalent precursor. Our lab has recently reported an alternative approach to this chemistry using an alkali metal and trivalent lanthanide systems that do not have reported molecular divalent states (LnZ3/K). To test the generality of this chemistry as a function of the ligand, Z, we extended the LnZ3/K approach to homoleptic organometallic precursors, specifically the tris(tetramethylcyclopentadienyl) lanthanide complexes (C5Me4H)3Ln (Ln = La, Nd). Both (C5Me4H)3La and (C5Me4H)3Nd react with KC8 in THF under dinitrogen to form bimetallic [(C5Me4H) 2Ln(THF)]2(m -h 2:h 2-N2) complexes of La and Nd. 1H and 13C NMR spectroscopy was used to analyze the reaction products of both systems. While the 1H NMR spectrum of the diamagnetic lanthanum dinitrogen complex displayed resonances consistent with its structure, the 1H NMR spectrum of the paramagnetic neodymium analog was not informative. The solid state structures of both La and Nd complexes show a side on bound (N=N)2- moiety located between two trivalent metals. These complexes provided new examples of the formerly rare Ln2(m -h 2:h 2-N2) coplanar core. Using this approach, we have successfully isolated and characterized the first diamagnetic lanthanum dinitrogen derivative. More generally, these results show that the LnZ3/KC8 dinitrogen reduction system can be extended to trivalent homoleptic organometallic precursors.
Genetic Cloning and Expression of the GAG3 Sequence in a Retrovirus-Like Element Ty3 in Saccharomyces cerevisiae
Mentor: Suzanne Sandmeyer
This study compares the protein expression of GAG3 reading frame alone with the wild type Ty3 expression. Ty3 virus-like element has an internal domain that consists of two open reading frames, GAG3 and POL3 similar to retrovirus Gag and Pol. We cloned the GAG3 sequence of the Ty3 element by polymerase chain reaction (PCR) and ligated the fragment into a plasmid vector. The GAG3 plasmids were transformed into E. Coli and amplified. After mini plasmid preparation we transformed yeast with the GAG3 plasmid and induced for expression. The result showed that without the POL3 sequence, proteins encoded by the GAG3 reading frame were not processed, and the protein yield was unexpectedly low. This presented an interesting observation and more studies would be done to provide explanation.
No Child Left Behind Act: The Effect on Latino English Language Learners
Mentors: Lisa Garcia-Bedolla & Mark P. Petracca
The No Child Left Behind Act was passed in 2002 as the reauthorization for the Elementary and Secondary Education Act of 1965. The four main goals of this policy are as follows: develop stronger accountability for results, provide more freedom for states and communities, encourage proven education methods, and offer more choices for parents. All students within the K-12 public education system, including Latino English Language Learners (ELL), are serviced by this policy. Research shows that Latino students educational success is highly influenced by outside environmental and family factors such as poverty, parental involvement, and language barriers. However, since the NCLB legislation was enacted, how the policy affects Latino ELL students has yet to be determined. This study is a normative analysis of the No Child Left Behind Act, which seeks to uncover the effects on Latino English Language Learners. I have learned that these students do not benefit from giving parents the option to move their children to better performing schools. In addition, forcing Latino ELL students to take a standardized test after being in the school system for only three years causes the child to be evaluated in a language in which they are not proficient. A policy that creates uniformity in the education of all students, fails to address the special needs of Latino English Language Learners. Therefore, this policy prevents Latino ELL students from succeeding to their full potential.
The Effects of Brood Sex Ratio Manipulation on Parental Care Allocation in Zebra Finches, Taeniopygia guttata
Mentor: Nancy Burley
Differences between male and female offspring can lead to one being more expensive to rear than the other, thus affecting the allocation of parental care and investment. Previous studies suggest that female chicks of zebra finches (Taeniopygia guttata) are more expensive to rear and cause greater costs to the parents fitness; thus we predict that male-biased broods would be in better condition and survive better that female-biased broods, receiving less allocation of care overall. To test this, we manipulated broods to all male, all female or a mix and recorded the parental care activities and durations at the nest. We also recorded the order of eggs laid, initial weight at switching, asynchrony among hatching dates, growth rates, survival and inter-clutch intervals (between nesting attempts). Our results showed that within the male-biased treatment, females fed more often, but in the female-biased treatment, males brooded more and were more defensive. Among the treatments though, the females spent more time in the nest in the mixed treatment than the sexually biased ones. There was a slight trend for the growth rate and percent survival to be higher for the female-biased treatment than the male-biased one. The egg order, initial weight and asynchrony of hatching did have a small effect on the survival of the nestlings. Overall, though, our data suggests trends that may support our hypotheses; we believe that we will find significantly stronger evidence when we complete analyses on the rest of our data.
The Effect of Alumina on the Ionic Conductivity of 8 mol% Yttria-Stabilized Zirconia
Mentor: Martha Mecartney
This study was conducted to determine how aluminum oxide (alumina) additions to 8 mol% yttria stabilized zirconia (YSZ) affect ionic conductivity. YSZ is used as a solid oxide electrolyte in fuel cells. Adding alumina can make the YSZ superplastic and easy to shape form. However, it was unknown how the alumina addition would affect ionic conductivity in YSZ and fuel cell performance. Impedance spectroscopy at temperatures from 350-700 ° C and analytical electron microscopy were used to characterize ionic conductivity of alumina-doped YSZ. The alumina dopant concentration varied from 0 to 10 wt%. Samples were sintered at 1450 ° C for two hr and annealed at 1530 ° C for three hr to achieve full densification. The addition of 1 wt% alumina led to increased grain size (from about 4 to 5 : m), whereas greater amounts led to decreased grain size (from about 2.5 to 1 : m) due to grain boundary pinning. Impedance analysis indicated that, although the total conductivity of the material was reduced at higher alumina concentrations, neither the grain interior conductivity nor the specific grain boundary conductivity were greatly reduced. The lower overall conductivity resulted rather from the grain-boundary pinning, which reduces grain size and therefore causes an increase in the volume percentage allocated to grain boundaries. Grain boundaries are much less conductive than grain interiors. Use of alumina to aid superplastic forming of zirconia should therefore be possible without sacrificing conductivity, provided that sufficient heat treatments are used to overcome the grain-boundary pinning effects of the alumina.
Differences in Drug Treatment Compliance Among First and Second Generation Mexican Americans in Southern California
Mentor: David Snow
According to the "Center on Juvenile and Criminal Justice" study in November of 2002, California leads the nation in drug offender imprisonment. An alternative to imprisonment was established with California's Proposition 36 that took effect on July 1, 2001, officially named the Substance Abuse and Crime Prevention Act of 2000 (SACPA). This proposition established a one year drug treatment program for drug offenders as an alternative to incarceration. The progress report of the "SACPA of 2002" shows that Los Angeles County, which has the highest number of Mexican Americans in its population, also has the lowest compliance recovery rate In order to examine the ineffectiveness of the program, the effect of acculturation on the compliance rate was studied. Ten first generation and ten second generation Mexican American "Prop 36" clients were interviewed in Los Angeles. The first generation clients, who are the least acculturated, had a higher rate of compliance. The deterioration of ethnic cultural values was found to be a risk factor for relapse to illicit drug use among Mexican Americans in recovery. These findings reinforce the need for culturally sensitive drug treatment programs that give a greater consideration to the clients socio-cultural values.
The Benefits of a Java Message Service (JMS) Implementation of the C2 Framework
Mentor: Richard Taylor
The C2 architectural style is a component- and message-based architectural style developed at UCI for constructing event-based, asynchronous software systems. Since the constraints of the C2 style are not well-matched to the Java programming language, which uses synchronous message passing, a framework such as c2.fw must be provided to bridge the gap between the capabilities of pure Java and the constraints of the C2 style. However, recently Message-Oriented Middleware (MOM) emerged, providing asynchronous message-based communication with many performance and integration benefits. I investigated the benefits of developing a C2 framework using BEA Weblogic Platforms implementation of the Java Message Service (JMS) interface. This JMS-based framework provides the same functionality, and applications are easily portable from one framework to the other. The purpose of constructing such a framework is to compare empirically its performance and throughput of messages with the current pure Java-based framework. Since the JMS implementation has more overhead, it performed slightly slower than the pure Java implementation. However, the performance setback is acceptable in consideration of the additional benefits of the JMS implementation, including guaranteed delivery of messages and distribution of the C2 architecture. Thus, this project demonstrates the advantage of employing commercial middleware products in developing efficient event-based, asynchronous software systems.
Actors on Acting Theory
Mentor: Leslie Ishii
The topic of acting theory is often overlooked for actors, yet many teachers and directors incorporate acting theories into their work with actors. Such acting theories come from acting theorists such as Constantin Stanislavsky, Stella Adler, Uta Hagen, Lee Strasberg, Bertolt Brecht, David Mamet, and Ann Bogart. Taking into account that acting theory is an integral part of the theatre world, it is important for actors to be knowledgeable about the different types of acting theories. By understanding the abundance of viewpoints about how one should act in the theatre, an actor has the resources to develop his or her own acting process. Through the UCIs first drama club entitled Theatre Ensemble Association (T.E.A.), members learned about acting theorists, and incorporated their theories. They had the opportunity to choose scenes from any type of literature, mostly classical and contemporary drama, and insert acting theories into their scenes. This research revealed that when actors experiment with different types of acting theories they show improvement in self-expression, confidence, and knowledge of their own acting style. To share these discoveries with other student actors and faculty members, actors will present these scenes in a culminating showcase during the 8th week of Spring Quarter.
Level of Encoding and False Memory Typicality
Mentor: Elizabeth Loftus
This study seeks to determine the role that levels of encoding exhibit in the occurrence of critical intrusions, particularly on measurements of central tendency (exemplar goodness). Individuals studied were undergraduate students enrolled in psychology courses. Employing the DRM paradigm, critical intrusions were created with categorized word lists of varying degrees of central tendency. Preliminary findings suggest that semantic encoding, relative to non-semantic encoding, produces a greater range of false memories, on measurements of central tendency.
Synthesis of an i -(iota) Type Amino Acid
Mentor: James Nowick
Synthesis and structural as well as biological studies of unnaturally occurring biological polymers has become an important area of research in modern organic chemistry with applications in such diverse fields as electronics, materials science, and drug discovery. The goal of this proposal was to develop an efficient synthetic way to make an alkoxy substituted iota-amino acid with the distance between carboxyl and amino terminus 4 times greater than that of naturally occurring alpha-amino acids, which will later be used as a building block to synthesize iota-peptides. The significance of this rather large difference in size between a and i -amino acids lies in the fact that i -amino acid based peptides can interact with larger areas of biological macromolecules. Examples of successful drug discovery efforts based on unnatural oligomers include Seebach's b -peptides that inhibit fat absorption in small intestine and cationic peptoids for gene delivery. During synthesis, benzylic bromination of one of the intermediates presented a formidable challenge. So much so, that I was forced to rethink the entire synthetic strategy. Instead of brominating at benzylic position, my product was brominated on the benzene ring. An alternative synthetic strategy was devised such that benzylic bromination could be avoided. The benzylic bromide that I now utilize is commercially available and is reasonably priced. I was able to synthesize the precursor to the synthetic target of this proposal and characterize all the intermediates by proton NMR and mass spectrometry.
High-Throughput, Low-Volume Protein Crystallization Screening
Mentors: Mark Bachman & Guann-Pyng Li
Protein crystallography is a vital area of research. Once a protein has been crystallized, its 3-D molecular structure can be determined through X-ray scattering, which is vital for disease research and understanding biological systems. Unfortunately, proteins are infamously difficult to crystallize. Each protein will crystallize only under very unique chemical conditions, which must be determined by trial and error. The protein solutions are highly purified and worth many times their weight in gold so small quantities must be used. The current screening process combines protein solution and buffer in different ratios by micro-pipetting--this is time-consuming, tedious, and error-prone by hand, and preclusively expensive to automate with robotics. My project explored methods of creating a high-throughput, low-volume microfluidic platform for protein crystallization. A microfluidic approach is faster, uses smaller volumes, and is much less expensive than robotic systems. The platform creates a series of droplets that gradually transition between different amounts of protein solution and buffer; a crystallographer can determine appropriate starting conditions by observing which droplets form crystals. This study identified two methods of forming droplets. The first involves creating drops in a T-intersection where oil and protein solution meet, forming nano-volume droplets. The second platform is a channel with regularly-spaced wide holes. It is prefilled with oil, and then injected with a stream of solution. The surface tension from the oil remaining in the wide holes causes the stream of solution to break into individual drops at precise locations and volumes. Future research will focus on the second technique.
Education: a Tool of Resistance
Mentor: Teresa Caldeira
Fifty years ago, Brazil was considered a racial democracy, a place where racial conflict did not contribute to social issues. Currently, Brazils racial democracy is considered a myth where its great level of social inequality does have a color line. Brazil is a country were most of the Afro-descendent population is marginalized and lives under extreme social conditions. Most blacks, mulattos, pardos or Afro-descendents hold blue-collar jobs, live in poor neighborhoods, and represent a minority in higher education institutions though they are about 50% of Brazils population. Nonetheless, education as a socializing institution can serve as an empowerment tool that strengthens the academic abilities of students, and makes a strong connection to their racial consciousness in order to resist the system of oppression. Therefore, my objective is to demonstrate that the implementation of educational programs that promote racial consciousness amongst blacks can serve as a tool to decrease institutionalized racism, and increase their attainment of a higher education.
How Culture Relates to Issues of Family Sleep Arrangements
Mentor: Wendy Goldberg
A multi-cultural sample of mothers of preschoolers completed questionnaires about family sleep arrangements, attitudes toward solitary versus co-sleeping and problems associated with child-related sleep issues. The surveys revealed that Asian and Mixed Culture groups were most likely to co-sleep, whereas Euro/Euro Americans were evenly split between solitary and co-sleeping. The Mixed Cultures group found co-sleeping most beneficial, followed by Asian/Asian Americans and lastly, Euro/Euro Americans. Attitudes toward the benefits of solitary sleeping did not differ among groups. Cultural groups related to mothers reported level of marital intimacy problems due to child sleep issues. Euro/Euro American mothers reported the lowest level of marital privacy problems and Asian/Asian American and mixed group mothers reported higher levels. Those groups most likely to co-sleep see this arrangement as fostering closeness, security and trust, but report challenges for marital intimacy. Discussion focuses on types of co-sleeping and challenges of various sleep arrangements for family life.
The Effects of El Niño Southern Oscillation on the Pacific Storm Tracks
Mentor: Jin-Yi Yu
The Pacific storm tracks are the paths that weather systems move from the mid-ocean to the West Coast of the United States. Variations in location and intensity of the storm tracks often result in prolonged drought or flooding events in California, Oregon, or Washington. A significant part of the year-to-year variation is related to El Nino Southern Oscillation, a warming or cooling of the sea surface temperature in the eastern tropical Pacific Ocean. However, the relationship between ENSO and the Pacific storm tracks has not yet been fully understood. Under this UROP project, professor JinYi Yu and I have analyzed climate data from NOAA to determine this relationship. It is found that ENSO has profoundly different effects on the two major components of the Pacific storm tracks: the subtropical jet stream and the polar jet stream. Using statistical methods, it is shown that ENSO affects the location and speed of the subtropical jet, but does not alter the location or speed of the polar jet. Also, the cooling phase of ENSO has been shown to increase the occurrence of a double jet stream.
Phosphorylation Site Identification: Discriminating Between Specific and Non-Specific Affinity Material Binding
Mentor: Agnes Henschen-Edman
Phosphorylation site identification has been of considerable interest in recent years. Phosphorylated fragments of the protein of interest have often been separated out by affinity binding to metal chelates or phosphorylation-specific antibodies attached to solid support. Non-specific binding is a serious and common problem. We have developed some simple procedures to improve upon the discrimination between true phosphopeptides and non-phosphopeptides. The proteins were S-pyridylethylated and then trypsin digested in triethanolamine buffer. The primary affinity materials tested were iron 3+ chelated to NTA- or IDA- agarose beads in column form. Bound peptides were eluted with ammonium bicarbonate. With sufficient material the peptides were quantified by sequencing. Half the bound material was digested with alkaline phosphatase. The two halves were subjected to MALDI-TOF mass spectrometry either separately or as a mixture. Phosphopeptides were easily recognized as pairs of components separated by 80 mass units corresponding to the loss of phosphate, non-phosphopeptides appearing as single, unrelated components. For proteins with known sequence the mass of the components provides sufficient identification, for unknown proteins ESI combined with mass-spectrometric sequencing is superior. With sufficient material RP-HPLC isolation of the peptides followed by sequencing is advantageous. Alternative identification of non-specifically binding peptides is obtained by phosphatase digestion before affinity binding to the iron 3+ NTA/IDA material or by using the NTA/IDA material in the absence of iron ions. The procedures described have been successfully utilized to unambiguously identify novel phosphorylation sites in animal fibrinogens.
Activation of PI-3/AKT Pathway by Estrogen and Testosterone in Male Cerebral Blood Vessels
Mentors: Diana Krause & Sue P. Duckles
Estrogen increases vasodilation whereas testosterone enhances vasoconstriction of cerebral vessels. 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/ Akt pathway is an important pathway for activating endothelial NO synthase (eNOS) to produce NO. We tested the 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, 1 m M). In the chronic study, rats were divided into 3 groups with 2 groups treated with hormone for 4 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 determined using Western blot. 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 regulated Akt phosphorylation. Activation of this kinase would be expected to increase production of NO in cerebral blood vessels.
People and Authorities, the Negotiation of War
Mentor: Sarah Farmer
Historians have analyzed the First World War from numerous viewpoints, not failing to note the crucially important fact that it "molded the 20th century". This research study presents a general point of view, which, since it is not limited to one individual aspect (for instance the social, military or diplomatic aspect), may provide a common element that can lead to a better understanding of the events. This element has proved to be the concept of novelty. Political and military authorities, soldiers and civilians were thrown into the enormity of a technological and total war in much the same way. All the individuals and groups who found themselves in direct contact with the war had to redefine their own system of values in order to embrace that which had been unimaginable before: the system of mass destruction and modern warfare. Starting from the central point of the element of novelty and from the necessity for change that this involves, the study then moves on to describe a world war which was different from that commonly written about by historians. The true contenders of this war were not the armies, which faced each other. The true objective of this conflict was no longer to preserve a system of government and of values in Europe. The war described in this work, obscured among the fighting forces and the authorities, was one in which the two contenders, armed with greatly differing weapons, came to grips in a dramatic way with the significance of this crushing new phenomenon. The stakes were not a military victory but, in the final analysis, the role that the masses would play in the subsequent forming of the nation states and of European history.
Determination of Optimal Complement Concentration Necessary to Produce Demyelination of the Spinal Cord Without Astrogliosis
Mentor: Hans Keirstead
After spinal cord injury, axonal regeneration fails due to the presence of a glial scar and myelin-associated inhibitors. In order to create a viable model for axonal regeneration, Hans Keirstead has developed a method to remove myelin and has demonstrated that this treatment facilitates axonal regeneration. This treatment consists of a single intraspinal injection of galactocerebroside antibodies plus serum complement proteins. Because of the nature of the complement injected, astrogliosis and formation of a glial scar around the region of demyelination is sometimes observed but less than usually seen following spinal cord injury. In this experiment we injected anti galactocerebroside antibody with 16.5, 22, 25, 33, 50 or 66% complement in order to determine the optimal percent complement concentration necessary to produce demyelination of the spinal cord without astrogliosis. Using the 16.5% complement injection produced demyelination with the least amount of astrogliosis.
California Public Policy Concerning Bilingual Education, Grades K-12
Mentor: Louis Desipio
Because of the high share of immigrants in the K-12 student population, California faces a more difficult task than many other states in providing public education to its students. This responsibility was made even more difficult when California voters passed Proposition 227, which largely prohibited school districts from providing multi-year bilingual education programs to non-English-speaking students. My research examines the propositions and laws that affect bilingual education and how these laws impact bilingual education programs. Specifically, I will be focusing on the Latino population. Latinos from Mexico constitute the biggest percentage of immigrants in California (Gonzalez, 2000), in part due to their close proximity. I analyze three local school districts: Westminster, Santa Ana, and Newport-Mesa to see how they deal with bilingual education. I will focus on policy procedures and changes, especially since the passage of recent propositions. The results of my analysis should provide a broader understanding for the implications of specific bilingual programs as well as offer a comprehensive comparison of the three trajectories of the school districts.
Dioxin and Host Susceptibility to Infection
Mentor: Sastry Gollapudi
Dioxin, an environmental pollutant, increases host susceptibility to infection, but little is known about the mechanisms by which this occurs. Recent research has identified a family of molecules known as the Toll-like receptors (TLRs) that play a key role in pathogen recognition and initiation of inflammatory and immune response. The purpose of this study was to determine the effect dioxin might have on the expression of TLRs and TLR signaling. A monocytic cell line (U937, ATCC) was cultured with various concentrations of Dioxin (1 ng/ml, 10 ng/ml, 50 ng/ml, and 100 ng/ml) for two weeks. Cells were stained phycoerythrin (PE) labeled monoclonal antibodies against TLR 2, TLR 4 and isotype control antibody. Dioxin treated and control cells were stimulated with lipopolysaccharde (LPS, 10 ug/ml), an agent known to trigger cell activation via TLR 4. Control and activated cells were permeabilized and stained with PE labeled anti-TNF-a antibody. 10,000 stained cells were acquired and analyzed by FACScan flow cytometer. TLR positive cells, TLR receptor density, as well as the percentage of TNF-a producing cells were determined using cell quest software program. Dioxin, in a concentration-dependent manner, inhibited the expression of TLR 2 and TLR 4. Altered expression of TLR 4 was associated with a decreased production of TNF-a . These data suggest that dioxin may increase host susceptibility to infection by modulating TLR expression and TLR signaling.
Micro-Devices for Protein Crystallization and Cell Assays
Mentor: Mark Bachman
Life scientists are turning to structural proteomics to help them understand and develop cures for many of today's diseases and biological hazards. Structural proteomics uses knowledge of the 3-D structure of proteins to determine how they work, and identify possible new drugs that can bind with them to cure diseases. 3-D structure is determined through a slow and painful process of expressing, purifying, and crystallizing the protein. From a protein crystal, X-ray diffraction can be performed, and the 3-D coordinates of every atom deduced. A major bottleneck in this process is protein crystallization, and recently, our research group sought to apply micro-engineering practices to improve the process. My project applies microfluidics technology to produce an environment that can crystallize a drop of protein less than 400 nl in volume. The crystallization process can be remotely controlled electronically, changing the humidity and acidity of the vapor surrounding the small drop, thus changing the concentration and pH within the drop. In this manner, we could direct the crystallization of miniscule amounts of protein, thus reducing the total amount of protein needed to perform this assay from milliliters to microliters. The chip was manufactured using a variety of manufacturing techniques, from conventional precision machining to clean room lithography. The micro-crystallization device was demonstrated by crystallizing two proteins, hen egg white lysozyme and sweet thaumatin. This project demonstrates a potentially powerful technology that can be applied to improving and lowering the cost of protein crystallization.
Interactive Broadcasting Studio
Mentors: Jill Beck & Feizal Waffarn
The Interactive Broadcasting Studio/Radio Show is a service and education-oriented initiative to benefit the pediatric patients at the University Children's Hospital at UCI Medical Center. The project is designed to (1) enhance patient care and comfort by reducing pain, anxiety, and boredom; introduce health education; and (2) empower children with a sense of autonomy and a medium for expressing themselves to their peers and health professionals within the hospital. The project also strives to provide a more holistic approach to the healing process by engaging children in activities that will allow them to have a direct impact on their immediate environment. The studio is a multidisciplinary effort from members of the Department of Pediatrics, Child Life Program, UCI College of Medicine, UCI School of the Arts, Health Artsbridge Program, and KUCI. These groups are working cooperatively to bridge the arts and medicine, which will improve pediatric care and outcomes. The program content will include both pre-scheduled events and live programming by patients and members of the multidisciplinary group.
The Effects of Normal Breast Tissue on E-cadherin Expression in Breast Cancer
Mentor: Philip Carpenter
E-cadherin is an epithelial membrane protein that acts in intercellular binding. It has been noted that metastasis, the invasive stage of cancer, is often accompanied by decreased levels of E-cadherin. Furthermore, it is known that several substances can act as motility factors and promote the separation of cancer cells from each other and the main tumor, thereby promoting metastasis. Our lab has previously shown that normal breast tissue secretes such substances, which increase motility in breast cancer cells (Carpenter and Nguyen, 1998). However, it is unclear how these motility factors act, and by what mechanisms they cause cell separation. In this study we investigate the effects of motility factors secreted by normal breast cells on the E-cadherin levels of MCF-7 breast cancer cells, and hypothesize that these motility factors will down regulate E-cadherin in cancer. We conducted three types of studies to test our hypothesis; E-cadherin staining, flow cytometry, and cell binding assays. We found that treating MCF-7 cells with normal breast cell secretions decreased not only the amount of E-cadherin staining exhibited by these cells and their ability to bind to other MCF-7 cells, but we also noted a near 25% decrease in E-cadherin levels by flow cytometry. Furthermore, our findings show a dose dependent decrease in E-cadherin staining with a corresponding increase in motility. By further elucidating the mechanisms by which these motility factors act, we can hope to create treatments, which inhibit their effects and thereby inhibit the cancer cell motility that they cause.
Parallelization Process with Efficiency
Mentor: Stephen Jenks
Living in the twenty-first century, processing data is not easy since machines that process extensive amounts of data in a reasonable and economically realistic time are not yet available. Instead of using one computer, a number of interconnected computers, a cluster, can be used to perform the same task. By dividing the job among processors, the efficiency and performance can be improved. Different portions of the code and data are assigned to different processors that run simultaneously, thus the ultimate solution is obtained by the combination of all individual processors. Repeating this procedure has brought scientists to explore different approaches to expedite the timely process of parallel programming. Parallel programming is used with data simulations of engineering applications. This project focuses on an Electro-Magnetic simulation using Maxwells equations in a 3-D Finite-Difference Time-Domain method. This has been proven to be an efficient tool for modeling microstrip antennas and other E-M systems. Parallel programming would be a good case to consider for this application, since FDTD program uses six 3-D arrays for modeling purposes, which increases the problem size to be an order of n3. The ultimate goal is to determine if using this linear approach would be as beneficial as a more complicated method of parallelization.
The Future of Practical Applications for Dosimetry
Mentor: Roger McWilliams
Dosimetry is the theory and application of the principles and techniques involved in the measurement and recording of radiation doses and dose rates. In essence, dosimetrists provide calculations and isodose distributions for interstitial and intracavitary radioactive sources to certain contours of the tumor in the least amount of dosage possible. Although advances for dosimetrists in areas of radiation accuracy and limits have been significantly improved, the costs and viability of procuring these advancements may be a factor for certain institutions. Cost vs. Quality of the procedure may become an issue whether or not it is worth treating a patient. Another issue is the lack of dosimetrists available to satisfy the demand for radiation therapy. To alleviate the issue of cost, advances in dosimetry will improve cost quality, such as a more accurate calculation for the distribution of dose in the contours and viable machinery advances such as chip and electronic advancements. The necessity for personnel may never change, but advancement machinery should make the current dosimetrists workload smaller. These advances are a necessity for the health of the patients and the success of dosimetrists treatments.
Staying Alive--Surviving the Banking Crisis of the Great Depression
Mentor: Gary Richardson
My project will be using primary data from the archives of the Federal Reserve and from the Rand McNally guide to finance institutions in New York. The years I am looking at are 1929-1934. This, coupled with census data on the demographics of the state of New York, gives us over 100 explanatory variables with thousands of entries. This is a sufficient data set to commence with my econometric analysis. The purpose of my paper will be to see the attributes of banks that survived the great depression, as well as attributes of banks that failed. My hypothesis is that large banks with lots of deposits and a good loan-to-deposit ratio, as well as federal backing were the banks that survived. The banks that failed were smaller with lower financial resources and no federal support. I will be running regressions on this data to derive the economically and statistically significant variables in the data set. I will be using STATA for the purpose of running these regressions and the consequent confidence intervals and hypothesis tests. In addition to the data I examined, I used an outside source to help me get perspective on what was going on. I read "The Great Contraction" by Milton Friedman, and will use its insights and ideas in my paper.
A Grammar-Based Multi-Platform Code Generator
Mentors: Roxana Diaconescu & Michael Franz
Automatic Code Distribution, or the partitioning of execution of applications across multiple devices, requires that pieces of a single program need to be compiled for different architectures. The goal of this research is to build a single flexible code generator that handles programs in various source languages and generates code for any platform of interest. To handle multiple inputs, we transform any given input in a common intermediate representation referred to as quads. We then create an Abstract Syntax Tree (AST) that describes the quad representation. To generate code for multiple platforms, we use a generic quad AST parser that can be specialized to the set of instructions specific to a given architecture. We describe the initial experience with implementing the multi-platform code generation tool for programs written in Java and discuss directions for future research.
Two Ribbons: An AIDS and Breast Cancer Benefit Concert
Mentor: Leslie Ishii
Art is a very complex word and area of study. Art comes in many forms and through each form lies the possibility of affecting someones life. Dating to the Golden Age of Greek Theater, art has been used to reflect society and inspire change. Music, Dance and Acting are forms of artistic expression and through these mediums a message can be conveyed. A message of hope and optimism is generally what the performer shares with the audience. Performing raises questions and offers solutions for the audience to integrate into their lives, or even inspire change for a better society. I learned that performing affects the audience in more ways than a performer could know, and vice versa. There is a special relationship that exists between the performer and the audience: they are working together--the performer to convey and the audience to receive. It is a symbiotic relationship that changes the life of the performer and the audience member. There is a lot of work that goes into performing; the process, or journey as it is also called, teaches performers about emotional capabilities, communication, and humility. In turn, the audience shares the journey within the duration of the performance. In two separate ways, both have grown and learned so much. Art is a strong source of positive social change, and hold an endless amount of possibilities of a better life for all.
Online Electoral Campaigning: Its Impact on Grassroots Politics, Donations, and Voter Turnout
Mentor: Caesar Sereseres
The Internet has steadily increased its impact on American presidential elections in the past decade. The two-way interactive nature and the ubiquitous nature of the Internet have revolutionized political campaigns. Through this new mode of candidate-voter interaction (coupled with traditional campaigning), John McCain running for president in 2000 and Howard Dean running for president in 2004 cultivated a financially viable campaign and garnered national support, in large part, through the Internet. This study undertakes an analysis of the effect of a decentralized political campaign structure on (1) grassroots support, (2) campaign donations to presidential campaigns, and (3) lack of voter turnout to win the elections in 2000 and 2004 presidential primaries. The Internet phenomenon propelled McCain in 2000 and Dean in 2004 to frontrunner status in presidential campaigns. Understanding the Internet in a presidential campaign provides a better perspective of the ever-changing candidate-voter interaction in an electoral political environment. Although the Internet was a supplemental tool to a major political campaign in 2000, the Internet has become an essential tool for grassroots organizing and fundraising in 2004. However, the success in Internet-based campaigning has not translated into sufficient votes to win the presidential primaries. The results demonstrate the Internet as a major source of grassroots support and campaign donations; yet the Internet has limited capabilities in providing sufficient voter turnout to win elections so far. The success and failures of McCain and Deans campaigns demonstrate an emerging trend of Internet-based campaigns and the attempts to capture election victory.
Real Time Data Acquisition and Analysis
Mentor: Bruce Tromberg
Real-time data acquisition and analysis allows for immediate detection of changes in optical properties of tissues. Current non-invasive optical cancer-detection techniques require 30 to 50 sec to acquire a data set. This data must then be analyzed in order to determine if the scanned tissue has a cancerous lesion beneath it or not. Real-time acquisition, which takes approximately 300 millisecond for a single data set, allows clinicians and researchers to detect variances more quickly, allowing for the lesion to be detected efficiently before the full data-set can be acquired on the appropriate area. All of these techniques utilize a broadband, multi-wavelength laser breast scanner currently in use in the Photon Migration lab at the Beckman Laser Institute. By combining the optical output of DC-powered laser diodes, with the efficiency of a spectrometer, the time needed to acquire the data is dramatically reduced. Analysis of the original raw-data, and implementing a number of C-code optimization techniques, allowed me to reduce the latency of the procedure from 30 sec (30,000 millisecond) to 300 millisec. This new technique allows clinicians to monitor changes in optical properties of any medium as it occurs, without the need for possibly misleading interpolation. Future applications of this acquisition technique will lead to breast imaging, and characterization of changes in tissue and muscle as soreness is introduced. Future research will aim to define a correlation between real-time data, and full data sets.
Victimization Patterns in Los Angeles: Who is at High Risk of Gang Violence and Where Does It Occur?
Mentor: George Tita
In order to understand the nature of gangs and their activities, one cannot avoid the issue of their territoriality. We explore the question: Is ones place of residency associated with ones gang territory? The answer to this question bears considerable weight in terms of the impact of gang violence on communities. If gang members spend most of their time in their gang territory instead of the neighborhood where they live, then communities where gangs hang out should be more susceptible to gang violence than the communities where they reside. The current study employs a quantitative approach by using the spatial typology of homicide developed by Tita and Griffiths (2003). The spatial typology categorizes homicide incidents based on the spatial relationship between offenders residence, victims residence, and location of the incident. We extend the typology to not only examining the residence of known gang members involved in homicide, but also where the turf of the gang member is located. The data we employ contain information on all homicides for the period 19902000 in two areas of Los Angeles: The Hollenbeck and the Southeast policing districts. We expect to find a noticeable contribution of territoriality information to the spatial typology. The potential findings could have implications for solutions to gang violence.
Memory for Chinese Characters
Mentor: Mark Steyvers
Recognition memory is typically researched by having participants study a list of words and then identify the previously studied words from a second list. Several factors have been shown to influence memory performance, including word familiarity, number of words in a list, and meaning. Our study looks to examine two of these effects: familiarity and meaning. However, instead of using words as stimuli, we use Chinese characters, and instead of a study list followed by a test list, we use a continuous recognition test, where each time a character is presented, a memory judgment is made. Our study looked at both the effect of "lag" (number of intervening items between identical characters) on performance, and the differences in performance between native and non-speakers of Chinese. We found that native speakers showed superior performance to non-speakers, and that both groups showed a decrease in performance as lag increased. We also found that when non-speakers repeat the task over several weeks, their performance increases to approximately the same as the initial performance of the native speakers. This suggests that becoming more familiar with the characters, though not explicitly learning meaning, increases memory performance. In the last portion of the study, we are pairing images with the characters to add meaning. We hope to replicate earlier findings showing that images aid in memory for characters, but only after a certain number of exposures. This would suggest that meaning is also a factor in memory, but takes longer to learn then simply becoming familiar with the characters.
Maggot Debridement Therapy for Non-Healing Wounds in Animals
Mentor: Ronald Sherman
Throughout history, maggots have been known for their healing ability when they infest wounds ("wound myiasis"). When intentionally placed into wounds (a process called Maggot Debridement Therapy or MDT) they assist in the healing of diabetic foot ulcers, pressure wounds, and other chronic wounds. However very little is known about MDT in non-human wounds. The goal of this project was to assess the benefits and risks of MDT in animals and veterinary wound care. All U.S. veterinarians known to have used MDT were sent surveys to elicit information regarding their experiences. All 8 veterinarians surveyed responded by describing their 1-11 patients each. Twenty cases were received: 2 dogs, 4 cats, 1 rabbit, and 13 horses. The maggots were used most commonly to debride necrotic tissue, control infection, induce healing, and to treat wounds that were unresponsive to conventional methods of therapy. In several cases, limbs were saved and euthanasia was avoided. No serious adverse events were reported. The overall consensus from the veterinarians was very positive. The overall consensus of the pet owners was positive as well. Our survey suggests that the advantages of MDT in treating cats, dogs, and horses outweigh the risks.
Response to Artificial Selection for Female and Male Floral Biomass Allocation in Gynodioecious Schiedea salicaria (Caryophyllaceae)
Mentors: Ann Sakai & Stephen G. Weller
The plant genus Schiedea exhibits a wide range of breeding systems. Phylogenetic analysis suggests that some species are undergoing evolution towards dioecy and show different stages of evolution. In order for changes in these breeding systems to occur, allocation of resources for male and female reproductive function must be heritable. Schiedea salicaria is a gynodioecious species with 13% females in the population and previous studies show it is under strong selection for separate sexes. This project studies the response of Schiedea salicaria to artificial selection to determine the genetic potential to change reproductive resource allocation. We artificially selected two lines for high female function (carpel and fruit biomass), two lines for high male function (stamen biomass), and had two control lines, based on the family means of the traits. Tradeoffs between male and female function were expected to occur, where the high female lines increased in carpel biomass and decreased in stamen biomass, and the high male lines increased in stamen biomass and decreased in carpel biomass. In high female lines, carpel and sepal/nectary biomass increased and stamen biomass did not change relative to the controls. High male lines showed increased stamen biomass and no change in carpel and sepal/nectary biomass. These results are consistent with the theory that this species has the potential to evolve dioecy through changes in biomass allocation.
Cross-Talk Between Integrins and Glutamate Receptor 1 Alters AMPA Receptor Surface Expression
Mentor: Christine Gall
The specific mechanisms of interactions between neuronal integrin adhesion proteins and AMPA neurotransmitter receptors are not known. The aim of this study was to test if integrin stimulation modifies surface expression of AMPA receptors containing the GluR1 subunit. Cultured slices were treated with the integrin ligands fibronectin (FN) and Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP) and incubated for different intervals. After treatment, levels of GluR1 protein on the cell surface were evaluated by surface biotinylation and Western blot methodologies. Results showed that as FN or RGD doses increased the amount of surface GluR1 also increased. The total surface expression of GluR1 remained fairly constant over different treatment periods whereas new membrane insertion of GluR1 was increased 15 min after ligand treatment. Levels of GluR1 insertion were not elevated at later time points. Together the data suggested that crosstalk did occur between integrins and AMPA receptor protein GluR1 and that integrins regulate AMPA receptor membrane insertion. These effects are transient following new integrin ligand exposure. The AMPA receptors are critical for learning and memory and current research suggests that regulated changes in membrane insertion are very important for these processes. Therefore, the present results indicate a mechanism that may be important for processes involved in synaptic plasticity in the mature brain.
AML-Aspect Markup Language: A Markup Language for Aspect-Oriented Programming
Mentor: Cristina Lopes
Aspect-oriented programming (AOP) is a programming technique that allows crosscutting concerns, design problems that spread globally across programming modules, to be abstracted and modularized. An aspect module consisting of binding instructions and executable code can be developed as a standalone programming unit and composed with the target system using a weaving tool or compiler. In this research, we propose Aspect Markup Language (AML), an XML-based language for defining aspects. This new AOP platform is applicable to different programming languages and supports modern software-engineering tools by leveraging the abundance of XML tools and techniques. In order to demonstrate the feasibility of our approach, we also present AMLs implementation for the Java programming language and translator, amljc, which is able to weave aspects written in AML grammar and Java components into target bytecode.
Association of Arterial Stiffness with Measures of Subclinical Atherosclerosis and Novel Cardiovascular Risk Factors
Mentor: Nathan Wong
Peripheral arterial disease (PAD) is a significant cause of morbidity and mortality that is associated with greater risk of cardiovascular disease, particularly in older individuals. Past studies have shown an association of both coronary artery calcium (CAC) and arterial stiffness with traditional risk factors, including hypertension, cigarette smoking, and diabetes; however, the exact relationship between subclinical atherosclerosis (as measured by CAC and ankle brachial index [ABI]) and arterial stiffness (as measured by pulse wave analysis) has not been well established. We acquired the patient's radial artery pressure waveforms, with augmentation index as an indication of arterial stiffness, to determine how it correlates with CAC, ABI, and cardiovascular risk factors. Doppler and sphygmomanometer equipment were used to measure ankle and brachial blood pressures and these values were converted into ABI. Total cholesterol, LDL, HDL, triglycerides, and C-reactive protein (CRP) were obtained from each patients blood sample. The consistently higher augmentation index (p<0.001) and ejection duration (p<0.05) measures in women as compared to men indicate increased arterial stiffness in women compared to men. While low ABI was strongly related to arterial stiffness, neither the presence of significant CAC or metabolic syndrome (MetS) was correlated with arterial stiffness. Further studies with a larger cohort are needed to ascertain if pulse wave analysis can provide additional value over standard and novel risk factors and other measures of subclinical disease in predicting cardiovascular risk.
Alpha 5 Integrin is Co-Localized With, and Signals Through, Pyk2 in CA1 Fields of Hippocampus: Implications for Cellular Mechanism of Long-Term Potentiation
Mentor: Christine Gall
Integrins are a family of transmembrane heterodimer receptor proteins that are involved in cell-cell and cell-matrix adhesion and in signal transduction that ultimately influences the differentiation, gene expression, and survival of the cell that expresses them. Recently, integrins along with Pyk2 (an intracellular signaling protein) have been separately implicated in the consolidation of long term potentiation (LTP), an activity-dependent model for learning and the formation of new memory. As a partial test of the hypothesis that integrins and Pyk2 are part of the same signaling pathway that influences LTP, the present study tested if alpha 5 integrin and Pyk2 were colocalized in single neurons and if alpha 5 integrin activation leads to activation of Pyk2. Results show that alpha 5 and Pyk2 are colocalized in apical dendrites of hippocampal pyramidal neurons and that activation of alpha5/beta1 integrin increases Pyk2 and Src phosphorylation in hippocampus. These results support the possibility that alpha5 integrin and Pyk2 work together in cellular mechanisms underlying hippocampal LTP consolidation and, quite possibly, memory.
The Interaction of Dopamine with Neurotransmitter Systems in the Basolateral Amygdala During Memory Consolidation
Mentor: James McGaugh
Several neurotransmitter systems within the basolateral amygdala (BLA), including the noradrenergic and cholinergic systems, influence memory consolidation for emotionally arousing events. Recent unpublished findings suggest that post-training intra-BLA infusions of dopamine (DA) enhance retention of inhibitory avoidance (IA) training. However, it remains unknown whether the mnemonic effects of DA depend on concurrent noradrenergic and cholinergic receptor activation. To address this issue, male Sprague-Dawley rats were surgically implanted with bilateral cannulas aimed at the BLA and trained on a step-through IA task. Rats received immediate post training infusions of DA with concurrent infusions of a b -adrenergic antagonist, a muscarinic cholinergic antagonist, or vehicle-control. The rats were tested for their retention 48 hr later. Infusions of DA alone significantly enhanced retention compared to vehicle-control infusions, whereas concurrent infusions of the b -adrenergic antagonist or cholinergic antagonist blocked the memory enhancement induced by DA. These findings suggest that the mnemonic effects of DA within the BLA depend on concurrent activation of b -adrenergic and muscarinic cholinergic receptors to influence memory consolidation.
Titin-Mimicking Multi-Domain Polymer Synthesis
Mentor: Zhibin Guan
There are three important properties for material performance: strength, toughness, and elasticity. Naturally occurring materials, like the muscle protein titin, have combined these three properties. In our pursuit of synthesizing an organic compound with optimum material performance, we have strived to mimic 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.