Summer 2017 Research Projects
Scholar: Tera Brandt
Mentor: Thomas Schermerhorn, Ph.D.
Effects of Glucose, Sucrose, and 2-Deoxy-glucose on Volume Regulation Responses of Canine Red Blood Cells
Serum tonicity reflects the total osmotic effects of serum constituents and is important for cell volume regulation. Serum hypertonicity, the condition of elevated tonicity, promotes human diabetes but is undefined in canines. Raised serum glucose (hyperglycemia), a feature of diabetes, also causes hypertonicity. We hypothesized that canine red blood cells (cRBCs) incubated in glucose, sucrose, or 2-DoG will react differently.
cRBC responses to hypotonic challenge were assessed using cRBCs incubated for 48-hr in 250mM NaCl containing 5.5, 33.3, or 66.6mM glucose, sucrose, or 2-DoG. RBC fragility was determined spectrophotometrically by measuring hemoglobin released from lysed RBCs. RBC diameter (dRBC) was determined using an electronic cell-counting device.
The results show that elevated glucose and sucrose levels (33.3 or 66.6mM) protected cRBCs against lysis. Elevated 2-DoG levels (66.6mM) increased cRBC lysis. Glucose shows effects similar to sucrose, therefore cells most likely adapt to glucose the same as sucrose by exporting fluids.
Scholar: Trevin Garcia
Mentor: Mary Kohn, Ph.D.
Latinx English in the Heartland: an Analysis of /l/ variation in a New Destination community
Changes to immigration policies and rural economies created population movements that have significantly altered the demographics of numerous rural US towns, creating new contact points for English and Spanish. This study focuses on language in Liberal, Kansas, a community where the Latinx community has grown from 19.5% of the population to 59.1% of the population over the past twentyfour years (US Census Bureau). This analysis contributes to research on Latinx English by examining /l/ realization in the speech of 15 Latinx and 8 Anglx Liberal, KS youths, a contact feature that has been found in other varieties of Latinx English.
Scholar: Alejandra Gonzalez
Mentor: Laura Valentín-Rivera, Ph.D.
Introduction of Spanish as a Heritage Language Learner in Higher Education: Assumptions versus Training
Heritage Language Learners (HLLs) have rapidly grown in the college education (Lynch 2003). Although enrollments in Spanish courses have increased, the number of the courses provided for Spanish HLLs are still limited (Rhodes and Branman, 1999). Thus, most of the Spanish HLLs have been in classes that are designed to teach traditional foreign language, that is: where English-dominant students learn a foreign language and re-teach the basics that they were supposed to learn at home (Valés 1997, 2003). According to Mikulski and Elola (2011), there are limited opportunities that are designed to keep track of HLLs' needs and for the training resources for Spanish instructors in charge of teaching Spanish to these types of learners. This limitation has led to insufficient comprehension of learning needs as well as the different levels among bilingual contact variation that complicate the effectiveness of teaching strategies within the classroom (Valdés, Fishman, Chavez & Perez 2008). To shed some light on this issue, this study analyzed whether Spanish instructors at the college level have pursued or received any training on the teaching of Spanish as a heritage language, as well as exploring the teaching strategies that these subjects execute in the heritage classroom.
Scholar: Demond Handley
Mentor: Majid Jaberi-Douraki, Ph.D.
Parameter Estimation in the Mathematical Modeling of the Skin Absorption of 14 Natural Compounds
Natural compounds consisted of essential oils and plant extracts are often consumed in the pharmaceutical and cosmeceutical industries. For this purpose, a surge of interest in chemical compounds to the perception of natural origin has been observed for the past decade, but to take into consideration the effects of these compounds on the skin as absorbed over time, it requires developing novel mathematical models. Parameter estimation is an important part of mathematical modeling, especially in the case of dermal absorption where rates must be determined for measurement of the permeant as it penetrates from one layer of the next over a predetermined period. This study is concerned with the estimation of flux parameters using a physiologically based mathematical model. The model consisted of a system of ordinary differential equations designed to measure concentration of a permeant over time. We estimated the flux parameters for measuring the dermal absorption of fourteen natural compounds along with a control compound, ethanol. We also determined the percent flux as the permeant passed through the skin surface, stratum corneum and viable skin layers. Once the parameters were optimally estimated, Markov Chain Monte Carlo methods were employed to discover the distribution of each parameter. Sensitivity Analysis using the extended Fourier Amplitude Sensitivity Test method determined which parameters caused the most effect on the model output.
Scholar: Kenyanna Jones
Mentor: Scott Beyer, Ph.D.
The Effect of Enzyme Function on Sorghum Based Diets for Broiler Chicks
This experiment was carried out in order to evaluate the effect of enzyme function on sorghum based diets for broiler chicks with the inclusion of two different enzymes; protease and phytase, given at two different levels. In this trial, 288 broiler chicks were distributed in batteries and assigned different diet treatments according to a completely randomized experimental design. The chicks were allocated to six treatments, eight replicates of six birds each to a pen. The treatments were fed to the chicks for 17 days, and afterwards the chicks and feed were weighed in order to see how much feed was consumed and how much the chicks grew. Afterwards, a bone sample was taken from each pen to determine how much calcium and phosphorous accumulated, and an ash was sample taken to test if one set of birds had stronger bones than the other based on which dietary treatments were consumed.
Scholar: Hannah Lusk
Mentor: Ruth Welti, Ph.D.
Identification and Characterization of an Arabidopsis Mutant Lacking Glycerolipid Assembly in the Chloroplast
Lipid analysis of leaves from the Arabidopsis T-DNA insertion line Salk_109175C revealed a significantly decreased ratio between two monogalactosydiacylglycerol molecular species, MGDG(18:3/16:3) and MGDG(18:3/18:3), as well as other lipid alterations, consistent with the mutant lacking the ability to assemble galactolipids in the chloroplast. Salk_109175C has an insertion in the gene At5g64790, which is mostly expressed in pollen. To confirm that the lipid phenotype observed was due to the known insertion, the Salk line was crossed to WT and the heterozygous progeny of this cross were self-pollinated to obtain an F2 generation. Analyzing the F2 generation to identify plants with the altered lipid composition and genotyping to identify plants containing the insertion in At5g64790 demonstrated that the insertion mutation and the lipid phenotype were not linked. These results indicate that the mutation causing the phenotype must be in another gene. We are using map-based cloning to identify the locus associated the lipid compositional alterations and conducting phenotypic assays to study the effect of this alteration on plant physiology.
Scholar: Austin Magette
Mentor: Jared Durtschi, Ph.D.
Do Parental Relationships Make a Difference in Marijuana Use in Lesbian, Gay, and Bisexual Emerging Adults?
Lesbian, gay, and bisexual (LGB) emerging adults often face additional stressors in their lives due to discrimination from friends, family, and culture (Balsam, Molina, & Lehavot, 2013). We used 1,268 adolescents longitudinally followed for seven years into emerging adulthood, drawn from Wave I and Wave III of The National Longitudinal Study of Adolescent to Adult Health (Add Health). Emerging adults who identified as a sexual minority had significantly lower odds of using marijuana in the condition when they had a stronger relationship with their mother and significantly higher odds of using marijuana when they had a stronger relationship with their father. Implications are to work with LGB youth and their families to create strong, loving relationships between parents and children and finding other methods for LGB youth to cope with many stressors that they face.
Scholar: Jennica Rogers
Mentor: Heather Bailey, Ph.D.
Memory Recall for Television Episodes Interrupted by Commercials Containing an Emotional Component
Boltz (1992) found memory recall for a television show was higher if commercial breaks were placed at breakpoint boundaries (a shift between two specific events) rather than non-breakpoint boundaries (take place in the middle of events). Three experiments were designed to see if her results could be replicated and extended to see whether or not interrupting the show with emotional commercials had different effects on memory. Experiment 1 determined whether or not the event boundaries Boltz’ (1992) participants found were accurate by using event segmentation measures with a higher number of participants. Experiment 2 used an emotional intensity rating scale to assess how emotionally intense commercials were to identify which ones should be used in Experiment 3. Experiment 1 showed variability in event boundary locations compared to Boltz’ (1992) event boundary locations. Experiment 3 will be conducted by using the results from experiment 1 and 2.
Scholar: Zaira Ruiz
Mentor: Alisa Garni, Ph.D.
Dairy Farming, Immigration, and Incorporation in Rural America
U.S. dairy farmers have recently begun hiring immigrant employees. Their increasing dependence on immigrant workers with limited legal rights means that dairy owners must help immigrant employees to settle in remote rural communities with few services or institutions to assist new comers, especially those from abroad and who lack many essential legal rights in the United States. How do dairy farmers’ efforts to assist immigrant employees in remote rural communities affect immigrant integration? In this study I build on previous research to to learn how dairy farmers’ efforts to recruit immigrant workers and help them settle affects their incorporation into the off-farm community. I conducted in-depth interviews with 11 immigrant employees in “Dairy City”, a rural American dairy town. I also spent time with immigrants to observe their local interactions and relationships with other community members. The data I gathered suggest that permanent employment in the dairies does promote immigrant incorporation by giving immigrants time to develop relationships with local residents, but that lingering language barriers inhibit fuller participation. In remote rural areas, language barriers are more significant than in urban areas where language programs and other institutions are available to assist residents. While immigrant incorporation is likely enhanced by permanent employment in dairies, unexploited opportunities to promote fuller integration remain.
Scholar: Shelbey Taylor
Mentor: James Lattimer, Ph.D.
Effect of protein supplementation on fiber disappearance and fermentation parameters using an equine cecal inoculum
Four cecally cannulated Quarter Horses were used to examine the effect of protein supplementation on fiber disappearance and fermentation parameters in vitro. Fermentation bottles containing buffered cecal fluid were used in a 2 x 5 factorial with four replications (horse). Factors consisted of substrate (alfalfa and native prairie hay) and sodium caseinate level (0%, 0.5%, 1.0%, 2.0% and 4.0%). Bottles were incubated for 48 h, at which time fluid and digesta was collected for pH, DM, NDF and ADF analyses. Sodium caseinate had no effect on pH, DM, NDF or ADF in bottles containing alfalfa. Bottles containing prairie hay and supplemented with 0.5%, 1.0%, 2.0% and 4.0% sodium caseinate had lower (p <0.05) pH when compared to the control. Dry matter, NDF and ADF disappearance were greater (p <0.05) in bottles containing prairie hay supplemented with 1.0%, 2.0% and 4.0% sodium caseinate when compared to the control. No differences were observed for any response variable between the 2.0% and 4.0% levels of sodium caseinate. Results from this study show that fiber disappearance can be enhanced by supplementing sodium caseinate to a low protein forage. This can be attributed to an increase in microbial fermentation activity or population. Supplementing sodium caseinate at a rate of 2.0% appears to be the most efficacious.
Scholar: Coraima Yañez
Mentor: Weiping Zhang, Ph.D.
Assessment of The Integrity and Temperature Stability of CFA/I/II/IV MEFA & Toxoid Fusion: Major Components of a Subunit Vaccine for Enterotoxigenic Escherichia coli (ETEC)
Diarrhea remains the second leading cause of death in children in developing countries, partaking in an estimated 1.5 million deaths per year. Enterotoxigenic Escherichia coli (ETEC) bacteria are among the top causes of children’s diarrhea and travelers’ diarrhea. Currently, there is no licensed vaccine against ETEC diarrhea. Two antigens, toxoid fusion 3xSTaN12S-dmLT and colonization factor antigen CFA/I/II/IV MEFA were demonstrated top antigen candidates for developing an effective subunit vaccine against ETEC. To further characterize these two antigens for protein integrity and particularly temperature stability, this study tested two proteins at temperature settings of 37°C and 50°C for six weeks. Results showed that toxoid fusion antigen 3xSTaN12S-dmLT was not stable at both temperatures. In fact 3xSTaN12S-dmLT protein started degradation on day 5-7 at 37⁰C and day 2 at 50⁰C. In contrast, protein CFA/I/II/IV MEFA was shown stable at both temperatures for at least 6 weeks. These results provided very helpful information regarding formulation, transportation and shelf life on a potential ETEC subunit vaccine.