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Community Composition of Fishes in Mission Bay
57 Studies
on a Synthetic Analogue of the Nitrile Hydratase Active Site
Andrea Ferrer Faculty Advisor: Ron Kaufmann Department of Marine Science and Environmental Studies
Madelegne Gerling Faculty Advisor: Christopher Daley Department of Chemistry and Biochemistry
Changes in hydrographic conditions can affect the diversity and abundance of fish populations in estuarine ecosystems. In Southern California estuaries, gradients in tidal flushing can lead to different communities in areas with different temperature and salinity regimes. For this study, fish community composition was examined by collecting samples with a beach seine in three different parts of Mission Bay: front, middle, and back, reflecting a gradient of decreased tidal flushing. Topsmelt (Atherinopsis californiensis) were the most abundant fish species at all three sites. In the front bay, arrow gobies (Clevelandia ios) were the other dominant fish species, whereas in the middle bay, anchovies (Engraulis mordax), California killifish (Fundulus parvipinnis), and shiner surfperch (Cymatogaster aggregrata) were most common. In the back bay, California killifish, arrow gobies, and mullet (Mugil cephalus) were the most abundant fish species. This study should increase our understanding of relationships between environmental conditions and estuarine fish communities.
53 Europe:
Nitrile hydratase is a metalloenzyme that catalyzes the conversion of nitriles to amides. The chemistry of this enzyme is due to the unique active site structure. The site contains a redox inactive metal ion bound to cysteine thiolates and backbone carboxamido nitrogens. Asymmetric oxidation of the cysteine bound thiolates is also observed. A synthetic analogue approach was used to examine the structure and function of NHase. In particular, we modeled the asymmetric, preoxidation, diamidatoditholate tetradentate plane of the active site for the Fe(III)-based enzyme by preparing an analogue ligand consisting of a dimethylated side chain in place of the native serine side chain. Characterization of the organic ligand precursors and all metal complexes is reported. Characterization techniques include NMR, UV-Vis, Electrospray Mass Spec, Cyclic Voltammetry and X-ray crystallography where possible. Progress on the thiolate oxidation studies of the Fe(III) analogue complex will also be discussed.
Fiscal Union or Failure?
59 A
Henry Frantz Faculty Advisor: Michael Pfau Department of Political Science and International Relations
DivK Homolog Induces Encystment in Rhodospirillum centenum
Daren Ginete Faculty Advisor: Terry Bird Department of Biology
The European sovereign debt crisis that followed the U.S. financial crisis of 2008 raised the question: to what extent has the lack of uniform budget requirements affected integration in the European Union? The current lack of fiscal unity in the EU suggests that member states place a higher value on state sovereignty than complete economic union, creating controversy as to the necessity of a fiscal union for the survival of the EU. Whether the EU survives the debt crisis and sees further integration will depend on member states’ willingness to give up sovereignty in order to create a stable fiscal union.
Rhodospirillum centenum is a purple photosynthetic proteobacteria that can form dormant cyst cells capable of withstanding prolonged starvation and dessication. Although morphological changes that occur in the transformation from vegetative cells to cyst cells have been established, the process that initiates encystment has yet to be understood. A recent study revealed that DNA-binding protein CtrA is involved in regulating the decision to differentiate into motile swarm cells or dormant cysts. In this study, I examined the response regulator DivK, a known inhibitor of CtrA activity in another, well characterized proteobacteria. From phenotypic analyses of a DivK mutant generated in R. centenum, I found that DivK functions as an inducer for cyst cell formation and suppressor for swarming motility. This result is consistent with the hypothesis that DivK has retained its role as a CtrA inhibitor in R. centenum.
55 Depression,
Anxiety, Stress, Locus of Control and Prescription Stimulant Misuse in a Southwestern University During Final Exams Tara Galvin Faculty Advisor: Michael Ichiyama Department of Psychological Sciences
Over the last twenty years, college students have increasingly turned to prescription ADHD medication, namely Adderall, Dexedrine, Ritalin, and Concerta as a way to increase academic productivity and concentration (Smith & Farah, 2011). In a study of 10,904 college students, McCabe, Knight, Teter and Wechsler (2005) found that 6.9% of those surveyed reported having used the drugs in their lives, but that prevalence varied widely among college campuses, from 0% to 25%. While much research has been devoted to identifying demographic data about the users of these medications, there lies a gap in research about their personal characteristics. This research aims to discover the relationship (if any) between USD students’ personal characteristics (locus of control, stress, depression and anxiety) and their decisions to or not to use prescription ADHD medication as a study method during final exams. Identifying these risk factors would help USD develop individualized intervention programs to curb this dangerous and illegal practice. 30 U n d e r g r a d u at e R e s e a r ch C o n f e r e n c e
/ First Session Poster Presentations
u n i v e r s i t y o f s a n d i e g O
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