Schedule of Events
Natural Science Oral Presentation Session
Seta Aghababian, Dr. Christopher Brown
Dr. Anita Stone
Is Play Sexually Dimorphic in the Polygamous Squirrel Monkey?
Squirrel monkeys are polygamous, characterized by strong adult male competition over females. This study examined whether social play is sexually dimorphic in juvenile squirrel monkeys, through a six-week field study on groups of Samiri collinsi in Amazonian Brazil. We predicted that juvenile males would show more rough-and-tumble (R&T) play than females and that any sex differences would be more evident in older juveniles. We video recorded play bouts (N=56 bouts) and scored: age category (younger juveniles: J1 and older juveniles: J2) and sex of players; and R&T play behaviors. Juvenile males initiated more bouts than females (N=48 initiations; χ2=7.97, p<0.05). Most players were J2 males, while J2 females were the least represented (N=125 players; χ2=22.5, p<0.05). J2 play bouts occurred mostly among males (96% of bouts), while J1 bouts consisted of a more even sex distribution of players (42% of bouts with both sexes). Random forest analyses in R showed that the number of males and of J2 players were the strongest predictive factors of the number of R&T behaviors (Male %IncMSE=8.77; J2 %IncMSE=11.3). We conclude that play is sexually dimorphic in juvenile S. collinsi; specifically, males play more than females and sex differences are more pronounced in older cohorts.
Javier Berjon de la Parra
Dr. Sebastian Carron Montero
Design and Construction of Optical Tweezers for Objects in the Micrometer Range
The 2019 Physics Nobel prize was awarded for the development of optical tweezing, a technique used to precisely manipulate microscopic objects with lasers. This development has had a tremendous impact for new experiments done in the fields of biology, chemistry and physics. The purpose of the project is to model, design and construct an instrument capable of optically manipulating objects ranging from 1 to 100 microns while simultaneously imaging them. For the modeling of this optical tweezer, a computer simulation that uses ray optics matrices was coded to obtain feasible lens arrangements to construct the tweezer. Using these data, an inverted microscope/tweezer was designed using 3D CAD software. Currently, the optical tweezer prototype is being constructed, and the appropriate laser beam conditions for tweezing have been achieved. Upon building completion of the instrument, its trapping capabilities will be experimentally determined. This instrument is expected to hold polymer spheres with diameters of a few microns, which can be used on experiments requiring small forces to be applied on cells or other microscopic objects.
Dr. Travis Peterson
The Influence of Golf Shaft Stiffness on Measures of Golf Swing Generation
Driving the golf ball toward a target downrange depends upon the generation of the swing from the ground up. This study aimed to investigate the influence of golf shaft characteristics on ground reaction forces. Seven highly skilled golf players (3 males, 4 females, 17-25 years old) volunteered to participate in accordance with the local institutional review board. The players performed 10 golf shots with golf clubs with different shaft stiffnesses as designated by the manufacturer (stiff versus extra stiff). Golf shots were measured using the players preferred address position with each foot fully supported by a force plate covered by a thin layer of artificial turf (1200 Hz, Kistler). Differences across the group of players between stiff and extra stiff shafts were determined using a paired t-test (α = .05). The shaft stiffness did not have an effect on peak reaction force magnitudes across the group. Reaction force generation was specific to the individual, but was not consistent across the group. Across the group, players generated greater peak reaction forces with the target leg compared to the rear leg in the mediolateral, anteroposterior and vertical directions for both shaft stiffnesses. The results of the study are important for golf players and coaches to understand how players generate the golf swing from the ground up with clubs of varying shaft properties. It could also help players choose club shaft characteristics to manage the subtle differences in reaction force generation that may cause large changes further downrange.
Dr. Karolynne Fogel
Analyzing CLU Voting By Shapley-Shubik Power Index
California Lutheran University is a growing institution, and with growth comes decisions that must be voted on. We investigated the voting power of the four divisions of the College of Arts and Sciences at CLU: Humanities, Natural Sciences, Social Sciences, and Creative Arts. Specifically, we wanted to understand how bloc voting affects the power of these divisions and if there is a way to generalize the Shapley-Shubik Power Index calculation in formulas. Throughout this research we calculated many divisions’ voting power for multiple years which led us to develop formulas and identify surprising results to better understand the distribution of voting power in the college at CLU.
Joanna Portillo, McKenzie Kelly, Lauren McAllister
Dr. David Marcey
Molecular Mapping of P-Transposable Element Insertions in the Genomes of Drosophila melanogaster Strains
Cryptic epigenetic variation may be an underappreciated component in the spectrum of natural variation upon which natural selection can act. To examine this phenomenon, we are studying a mutation known as the extra eye mutation (ee). Here we propose an epigenetic model for the production of head deformities by the extra eye mutation (ee), which is incompletely penetrant, variably expressed, and conditionally dominant. The model posits RNAi-mediated transcriptional suppression via epigenetic heterochromatization of a gene that encodes a repressor of activated STAT, a key molecule in the JAK-STAT signaling cascade implicated in embryonic eye field establishment. In ee strains, a P-transposable element insertion maps near a gene, Su(var)2-10, and is the putative target of RNAi-induced heterochromatization. This work uses a variation of the polymerase chain reaction, Splinkerette PCR, to capture genomic sequences that flank P-element inserts in the ee strain, which are then subjected to next generation DNA sequencing. The resulting sequences are aligned to the D. melanogaster reference genome with bioinformatic software. As one test of the model involving Su(var)2-10, we expect to precisely map the P-element insertion near this gene, and thereby determine the plausibility of its RNAi induced heterochromatization. In collateral studies, Splinkerette PCR of genomic sequences flanking P inserts in other putative P-element induced mutations is being conducted. To date, multiple Splinkerette PCR amplicons have been mapped and further analysis of these genomic fragments sequences is underway.
Dr. Jesus Cordova
Base-catalyzed Synthesis of Indoles
Indoles are heterocyclic compounds that are commonly found in nature and play a significant biological role when isolated and combined with other compounds or organic molecules. This allows for diverse applications of indoles in drug synthesis, medicine, and pharmacology. The ability of indoles to inhibit tumor growth and block biological receptors by replicating the structure of an organism’s proteins makes them an ideal compound for the treatment of certain cancers, infectious diseases, and psychological disorders. The goal of this research is to determine an efficient synthesis of indoles in two steps using commercially available starting materials. This process will represent an effective method for the synthesis of indoles and use less toxic starting materials than the currently used methods. Also, it could potentially reduce the cost of production for medications containing this functional group. Previously, in August 2018, a tetrahydrocarbazole derivative of the desired indole product was synthesized in two steps. In the summer if 2019, a successful Suzuki coupling reaction between 2-phenylvinyl boronic acid and 2-iodoaniline was achieved in 94% yield. The resulting bicyclic molecule was subjected to several different cyclization conditions which consist of a base, solvent, and oxidizing agent. None of the cyclization conditions attempted were successful in creating the desired indole product. Current work includes a new two-step synthesis which focuses on a reaction between 2-iodoaniline and 3-bromo-4-ethoxy-1,1,1-trifluorobut-3-en-1-one. A successful Michael addition reaction followed by an Ullman coupling of these two reagents was achieved to form a new product. In the future, this molecule will be subjected to 1H NMR for further characterization and to determine if it is the desired product.