«Strengthening the Nation through Diversity, Innovation & Leadership in STEM San Antonio,Texas · October 3-6, 2013 Get Connected! Connect with the ...»
Published literature documents that underrepresented US minorities (URMs) including African-, Latin-, and NativeAmericans in STEM fare better if they have a science identity that does not conflict with ethnic identity. Furthermore, it has been shown that URMs may benefit from having cultural mentors. This study will assess the relationship between the presence of traditional Elder educators in a STEM course, student science identity, and course learning outcomes.
We hypothesize that science identity will mediate the effects of cultural mentors (Elders) on learning outcomes for all students, and especially for URMs. A short-term, longitudinal study will be conducted on a STEM online course delivered either with or without Elders. Two mainstream research-intensive universities and two tribal colleges/ universities will be the sites of the course delivery (May through June 2013). Students who are enrolled in the course may choose to participate in this research approved by appropriate institutional research ethics boards. Participants will take a pre- and post-course survey. We will test for group differences with ANOVA and establish predictor variables with regression modeling using SPSS software. We expect to find that student science identity mediates the effects of cultural support (presence of traditional Elder instructors in an online STEM course) on learning outcomes.
We expect to find that science identity and cultural support predict students’ learning outcomes in an online STEM course. These findings can impact science education policy, research, and pedagogy to benefit URM students in STEM.
OTHER BIOLOGICAL SCIENCES
IMPROVING ACCURACY OF STEREOTAXIC COORDINATES IN JUVENILE RODENTSAcacia Nawrocik, Carlos Paladini.
University of Texas at San Antonio, San Antonio, TX.
Currently, the Paxinos Rat Brain Stereotaxic Atlas is used to obtain the optimal coordinates for targeting rat brain structures. However, this atlas is based on an average of mature male Wistar rats and is inadequate for targeting nuclei in young rats at ages postnatal days 14 through 21 (P14-21). The purpose of this study is to obtain accurate coordinates for the subthalamic and pedunculopontine tegmental nuclei in female and male rats in this age range.
First, we will confirm existing coordinates in mature Sprague-Dawley rats through injection of red dye beads followed by histological analysis of their locations. Then, we will make proportional modifications of the coordinates, using bregma to lambda distance. The coordinates will be adjusted until reliable stereotaxic coordinates are developed for several regions within each nucleus. These findings will allow us to analyze projections to and from subregions of the nuclei in virally-infected neuronal tissue marked with a fluorescent protein.(This experiment is partially supported by NIGMS RISE GM60655, and NIMH.) FRI-606
THE INFLUENCE OF VISUOSPATIAL ATTENTION ON UNATTENDED AUDITORY CORTICAL RESPONSESCullen Roth, David Bridwell, Sergei Plis, Cota Navin Gupta, Eswar Damaraju, Siddharth Khullar, Vince D. Calhoun.
University of New Mexico, Albuquerque, NM.
Recent advances in EEG technology have made it possible to record EEG within natural settings. However, these recordings are difficult to analyze due to movement artifacts and complex environmental stimuli. Using cortical responses to periodic auditory input, these difficulties can be minimized. Such steady-state responses (SSRs) may be measured even when individuals are not attending to the periodic input. We examined whether cortical responses to an unattended auditory flicker are modulated by visuospatial attention. Using the Actiwavetm mobile device, 8-channel EEG data was collected from healthy subjects: N = 6. SSRs to 40 Hz auditory tone bursts (70 bB) were measured while individuals participated in a “difficult” or “easy” visuospatial task: the game Tetris. These SSRs were compared with SSRs when individuals attended to the auditory bursts. SSRs were isolated using Fourier analysis. The 40 Hz SSR was divided by the response within 38 and 42 Hz, generating the signal-to-noise ratio (SNR). The average log
EXERCISE AND EPILEPSY: ALTERING SEIZURE SUSCEPTIBILITY BY INCREASING THE PRODUCTION OF
NEWLY-BORN GRANULE CELLSSamantha Mohammad, Guido Faas, Istvan Mody.
University of California, Los Angeles, Los Angeles, CA.
Epilepsy is a lifelong disorder characterized by the production of seizures. There are currently several preventive medications available. In addition, studies have shown that there are more natural methods to prevent epileptic seizures. Exercise after epileptic onset is one such method that reduces epileptic symptoms. However, the mechanism by which this occurs remains unknown. Interestingly, exercise increases the production of newly born dentate gyrus (DG) granule cells (GC). The DG is one of the few regions of the brain highly affected by epilepsy and produces newly born DGGCs. Another interesting fact is that seizures also produce an increase in production of newly born DGGCs, which could be a compensatory mechanism to reduce seizure susceptibility. We examined whether the exercise-induced increase of newly born DGGCs prior to epileptic onset is the cause for the reduction in seizure susceptibility. To test this, mice were separated into control (nonrunning) and running groups, with the latter given running wheels to increase the amount of DGGCs produced. All mice were then injected with kainate to trigger status epilepticus, and seizures were scored using the Racine scale. The increased number of DGGCs within running mice was expected to decrease the severity and frequency of seizures. Our results have shown that exercise prior to epileptic onset reduces the recovery period as compared to control animals. Continuation of our research will allow us to identify whether these newly born DGGCs contribute to exercise-induced reduction in seizure severity.
MORPHOLOGICAL ANALYSIS OF RANA EVERETTIAllyson Prue1, Rafe Brown2.
Haskell Indian Nations University, Lawrence, KS, 2University of Kansas, Lawrence, KS.
1 The purpose of this research project is to identify a cryptic species in Rana everetti, a frog species located on Mindanao Island in the Philippine archipelago, through morphology. Previous genetic analysis showed genetic variation within the species and introduced the possibility of 2 distinct species under the same name. Geographical differences also contribute to the hypothesis of 2 distinct species; “real” R. everetti is located on Mindanao Island while the cryptic species is located on the island of Negros. Morphological analyses of specimens collected from the archipelago were conducted and determined the validity in the hypothesis. Twenty-five cryptic species and nine “real” R. everetti were measured, including both adult males and females. The outcome of this project is the identification of the cryptic species which would lead to its discovery and eventual naming.
CAFFEINE THERAPY’S EFFECTS ON CENTRAL RESPIRATORY CHEMORECEPTION AND ITS ROLE IN
SUDDEN INFANT DEATH SYNDROMEAryana Cruz, James Bane, Brian O’Grady, Sarah Aceves, Matthew Gdovin.
University of Texas at San Antonio, San Antonio, TX.
In the United States, the leading cause of death of infants is sudden infant death syndrome (SIDS), the cause of which is still unknown. Caffeine therapy has been effective in reducing the incidence of SIDS in preterm human infants; however, the mechanisms of caffeine’s efficacy are unknown. In this lab, an in vitro larval Lithobates catesbeianus (American bullfrog) whole brainstem preparation is used as a model for the infant respiratory circuit while allowing manipulation for extended amounts of time. Experiments were designed to test the hypothesis that a failure in CO2 chemoreception in the brain prevents infants from responding to hypercapnic conditions. Gill and lung patterns are monitored in the control and caffeine-treated tadpoles via cranial nerve (CN) VII. The firing rates of neurons in a central respiratory chemoreceptive area are monitored via their extracellular field potentials. The pHsensitive dye BCECF is used to determine the intracellular pH (pHi) of the target neurons. Experiments are conducted
143 UNDERGRADUATE POSTER ABSTRACTS
in normocapnic (bath pH = 7.8) and hypercapnic (7.4) conditions. During hypercapnia, the control motor output increases and is expected to be directly proportional to the firing rate of action potentials and inversely proportional to the pHi of the neuron, self-regulating their pHi. In tadpoles chronically exposed to caffeine, the motor output increases dramatically in hypercapnic conditions, with no regulation of pHi. By performing these experiments, the potential mechanisms underlying SIDS can be studied and alternative treatments to caffeine could be discovered. (Supported by TWD MARC GM07717 and NIH-NCRR 5G12 RR013646-08.) SAT-607
CONDITIONED TASTE AVERSION DOES NOT REQUIRE CORTICAL MRNA SYNTHESISYasmin Marrero-Garcia, Abigail A. Russo, Donald B. Katz.
Brandeis University, Waltham, MA.
The neurobiological mechanisms by which memory consolidation occur depend on the type of sensory information and where it is being stored. It has been established that gustatory cortex (GC) is necessary for consolidation of taste memory, yet the physiological mechanisms that underlie this process have not been thoroughly investigated.
Findings suggest taste memory acquisition is dependent on cortical protein synthesis, but have left unaddressed the role cortical gene transcription plays in the learning process. Using actinomycin D (Act-D), a broad mRNA transcription inhibitor, we are investigating the molecular underpinnings of taste memory acquisition in GC. During conditioned taste aversion (CTA) training, wherein rats are exposed to a taste paired with malaise, we microinfused Act-D into cannuale bilaterally implanted into GC. Our data suggests that memory consolidation is independent of mRNA synthesis, at least in GC; all animals learned the appropriate aversion to the taste. It is likely that subcortical production of mRNA, presumably in the amygdala, is sufficient to support cortical protein synthesis and establish taste memory.
A PHYLOGEOGRAPHICAL STUDY OF MABUYA DORSIVITTATA IN BRAZILIAN FORESTSDanielle Rivera, Ana Carolina Carnaval.
The City College of New York, New York, NY.
South American montane species are under serious threat from anthropogenic and climatic forces. This analysis examines the patterns and levels of genetic diversity in a broadly ranged skink that belongs to the vastly understudied South American genus Mabuya. M. dorsivittata (Squamata: Scincidae) is distributed throughout the Brazilian Atlantic Forest mountains, the Cerrado, and the Argentinian Chaco. To describe phylogeographical patterns within this species, I extracted, amplified, and sequenced DNA from 43 specimens distributed across 21 sites. Fragments of 1 mitochondrial and 6 nuclear genes were analyzed, and a Bayesian inference method was implemented to delineate genetic variation and genetic structure. MaxEnt was used to model the species distribution during the Last Glacial Maximum (LGM), a climatically cooler period during which several tropical species’ distributions shifted. Distribution models indicate that the range of this species was relatively unfragmented during the LGM. My phylogeographic study indicates high levels of genetic structure and deep genetic divergence between geographically separated populations, reaching up to 10% divergence in the mitochondrial gene. It can be posited that a historical geological divide promoted divergence within M. dorsivittata, delimiting two major clades that are geographically separated along the coastal forest (one to the north and one south of the Tietê River). Similar genetic breaks observed in other species occurring in the same region contribute to this hypothesis. Further inclusion of samples from the Cerrado and the Chaco are needed to determine whether similarly deep genetic breaks are found within the remaining species’ range.
EWING SARCOMA AND SMARCB1Sam Hawkins, Lisa Abegglen.
Huntsman Cancer Institute, Salt Lake City, UT.
Ewing sarcoma is a rare pediatric bone cancer. Nearly all Ewing sarcoma tumors have a chromosomal translocation which results in cellular transformation. In addition, Ewing sarcoma tumors with other genetic variations have been identified, including alterations in P53, CDKN2A, MDM4, and SMARCB1. Interestingly, SMARCB1 deletion is characteristic and used in the diagnosis of rhabdoid tumors. SMARCB1 gene deletion occurs in a small subset of Ewing sarcoma tumors and could lead to a new sub classification of Ewing sarcoma. Currently, the Schiffman Laboratory is investigating SMARCB1 gene function in Ewing sarcoma. To determine the role of SMARCB1, gene knockdown experimentation will be utilized. Previous research from the literature shows that normal cell lines
THE EFFECTS OF METHYLMERCURY ON RNA EXPRESSION OF CALCIUM PERMEABLE ION CHANNELS IN
DIFFERENTIATED AND UNDIFFERENTIATED F11 CELLSKia Perez Vale1, Heidi Hannon2, Bill Atchison3.
University of Puerto Rico, Arecibo, PR, 2Michigan State University, East Lansing, MI, 3Michigan State University, 1 College of Veterinary Medicine, East Lansing, MI.
Methylmercury (MeHg) is a globally distributed environmental contaminant that bioaccumulates in the aquatic food chain making it of great concern because eventually it will enter the human diet. Exposure to MeHg causes damage to the peripheral and central nervous systems, producing sensory neuropathies and ataxia, and can contribute to the development of neurodegenerative diseases. Although the mechanisms of MeHg neurotoxicity are not fully understood, MeHg exposure can result in disruption of protein synthesis, synaptic function, and neuronal excitability.