K-State Graduate Research, Arts, and Discovery (K-GRAD) Forum
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The K-State GRAD Forum is an annual showcase of K-State graduate student research, scholarly work, and discovery. This on-campus event provides graduate students from all disciplines an opportunity to share their work with the K-State community and to gain experience presenting their work in a professional setting. The event was previously named the K-State Research Forum till 2015.
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Item Open Access Understanding sexual prejudice among midwestern pre-service and in-service teachers: some quantitative results(2014-05-09) Foy, Joelyn K.Sexual orientation is only one facet of diversity (Banks et al., 2005), but teacher preparation may not adequately address sexual prejudice (Lamb, 2013). Quantitative results from a mixed methods design will be presented. BACKGROUND AND PURPOSE: School environments reinforce heteronormativity (Dean, 2010; Foucault, 1990; Himmelstein & Bruckner, 2011) such that when hate speech or physical violence occur against the non-hetersexual or the transgender student, teachers may not be prepared to respond appropriately. Students victimized because of their gender or sexual variance are more likely to skip school, resulting in lower GPAs; and are less likely to attend college (GLSEN, 2010). How do levels of sexual prejudice differ as a function of demographic, educational, and personal characteristics? METHOD: Survey results were collected from pre-service (undergraduate) and in-service teachers (graduate students). Group means of the PREJUDICE scale for each independent variable were analyzed for statistical significance. RESULTS/FINDINGS: The total variance of the PREJUDICE scale was accounted for by personal characteristics only (political, 30%; religious, 20%; non-heterosexual friends, 16%; and family members, 12%; participant sexual orientation, 8%; and finishing the survey, 4%). Neither demographic nor educational characteristics accounted for statistically significant differences in group means of the PREJUDICE scale. CONCLUSION: We do not accept or reject teacher education candidates based upon their sexual orientation or how many friends and family members they have who are non-heterosexual. Significantly lower levels of sexual prejudice were associated with having non-heterosexual friends and family members or being non-heterosexual, and there were no significant effects from educational interventions.Item Open Access The mathematics of homophobic bullying(2013-02-01) Foy, Joelyn K.; jofoyItem Open Access Variation in susceptibility of insects associated with Kansas farm-stored grain to insecticides recommended for empty bin treatments(2013-01-29) Sehgal, Blossom; blossomProducers apply insecticides to empty bins to kill insects prior to storing newly-harvested grain. We evaluated time-dependent immediate knockdown (KD) and 7-day mortality responses of adults of 16 strains of the red flour beetle, 7 strains of the sawtoothed grain beetle and 2 strains of the lesser grain borer collected from Kansas farms exposed on concrete surfaces to β-cyfluthrin, at low (0.086 mg(AI)/m2) and high (0.172 mg(AI)/ m2) rates, and chlorpyrifos-methyl plus deltamethrin (0.573 mg(AI)/m2). Similar species reared since 1999 served as standard laboratory strains. The minimum time for KD and mortality of laboratory strains was established through time-response studies. Time for 100% KD and mortality was selected for each insecticide-species combination for testing against field strains. Mortality of all species against the two insecticides was lower than KD, suggesting recovery when placed on food. Nonlinear or linear models fitted to KD and mortality data showed significant differences among species and insecticides. Only one red flour beetle strain showed reduced susceptibility to the two insecticides compared to the laboratory strain. Both field strains of lesser grain borers were less susceptible than the laboratory strain to chlorpyrifos-methyl plus deltamethrin but not to β-cyfluthrin. In sawtoothed grain beetle, one strain was significantly less susceptible to chlorpyrifos-methyl plus deltamethrin than the laboratory strain, and two field strains were significantly less susceptible to β-cyfluthrin. Reduced susceptibility in field strains could be due to development of resistance. These findings can be used to make recommendations to producers for improved stored-grain insect management.Item Open Access Flux growth of cubic boron phosphide crystals(2013-01-29) Nwagwu, Ugochukwu; Edgar, James H.; Gong, Yinyan; Kuball, Martin; d0444080; edgarjhThe ability to intercept attempts to smuggle nuclear weapons into the United States is critically important for homeland security. New types of neutron detectors are especially needed, as current devices employ a rare helium isotope (3He), which was a byproduct of the production of hydrogen bombs. As the production of nuclear weapons has largely ceased and the need for homeland security has grown, demand for 3He has greatly exceeded supply. Boron phosphide, BP, a compound semiconductor, is a potential alternative for neutron detectors because of the large thermal neutron capture cross-section of the boron-10 isotope (3840 barns). In this study, cubic BP crystals were grown by crystallizing dissolved boron and phosphorus from a nickel solvent in a sealed (initially evacuated) quartz tube. The boron - nickel solution was located at one end of the tube and held at 1150°C. Phosphorus, initially at the opposite end of the tube at a temperature of 430°C, vaporized producing a pressure of 1–5 atmospheres. Transparent red BP crystals, mostly hexagonal shape and up to 2mm in the largest dimension were obtained with a cooling rate of 3°C per hour, and less than 0.5mm with a cooling rate of 10°C per hour. The lattice constant of the crystals was 4.534Ǻ, as measured by x-ray diffraction. Intense, sharp Raman phonon peaks were located at 800cm-1 and 830cm-1, in agreement to values reported in the literature. Energy dispersive x-ray spectroscopy (EDS) and scanning electron microscope (SEM) also confirmed the synthesized crystals were cubic BP crystals, with boron to phosphorus atomic ratio of 1:1. Therefore, this flux growth method is capable of growing large, high quality BP crystals.Item Open Access Microbial ecology of stable flies: Effect of bacterial community of aging horse manure on stable fly oviposition and larval development(2012-12-19) Albuquerque, Thais Aguiar De; Zurek, Ludek; thais; lzurekStable flies (SF) are blood-sucking insects with great negative impact on livestock. SF larvae develop primarily in animal manure. Our hypothesis was that the microbial community in animal manure changes over time and plays an important role in SF oviposition and development. Two-choice bioassays were conducted using 2- week old horse manure (standard) and aging horse manure (fresh to 5 weeks old) to evaluate the effect of manure age on SF oviposition and larval development. Results showed that fresh manure is not attractive for SF oviposition and that the attractiveness increases as manure ages but declines from 4 weeks of age. Eggs artificially deposited on 1, 2 and 3 weeks old manure resulted in significantly higher SF survival comparing to that of fresh, 4, and 5 week old manure. The bacterial community of horse manure was analyzed by 454- pyrosequencing. The microbial structure shifted from strict anaerobes (Clostridium, Eubacterium, Bacteroides, Ruminococcus) in fresh manure to facultative anaerobes/aerobes (Bacillus, Stenotrophomonas, Brevundimonas, Sphingomonas, and Pseudomonas) in 1-4 week old manure. In conclusion, the microbial community in 2-3 weeks old horse manure is the most attractive for SF oviposition and provides the suitable habitat for SF development. Manure of this age should be the main target for disrupting SF life cycle to manage SF around livestock. Better understanding of SF microbial ecology is critical for development of novel SF management strategies that could be based on alteration of the microbial community of SF habitat to generate a substrate non-conducive to fly oviposition and/or larval developmentItem Open Access Infrared spectroscopy as a compliment to X-ray diffraction for zeolite examination(2011-07-29) Tomlinson, Sean R.; McGown, Ty; Schlup, John; Anthony, Jennifer L.; srt5555; jrsch; anthonyjX-ray diffraction is commonly used to examine zeolite structure, but it is unable to see small changes in the long-or short-range structure. Infrared spectroscopy is used to examine changes in the long-and short-range structure of zeolite. Structural changes in zeolite CIT-6 and derivatives upon chemical treatment are identified with mid-and far-infrared spectroscopy. Differences in the local structure of the sample are observed in the mid-and far-infrared spectra.Item Open Access Allometric model for quantification of sorghum canopy formation(2011-07-07) Narayanan, Sruthi; Aiken, Robert M.; Paul, George; nsruthi; raiken; gpaulCanopy architecture has a prominent role in fundamental processes of crop growth including light transmission and interception, evapotranspiration and photosynthesis. Leaf Area Index (LAI)is a commonly used parameter for analyzing vegetative canopy structure and it can directly quantify canopy architecture (Welles and Norman, 1991). Tewolde et al. (2005) identified LAI as the key parameter in the analysis of crop growth and productivity. Leaf area index and total dry matter increment determine the transpiration efficiency and water use efficiency in a sparse crop (Kato et al., 2004). Quantification of LAI has potential in understanding resource use efficiency and productivity of a crop. Several complex models have been proposed to simulate leaf area index (LAI) in sorghum (Sorghum bicolor (L.) Moench) (Hammer et al., 1993), but a thorough inclusion of total mature and immature leaf area is lacking in these models. Objective: Develop a simple quantitative model to predict LAI for sorghum from emergence to flag leaf stage.Item Open Access Dry thermal oxidation of GaN with SEM, AFM and XPS characterization(2011-06-27) Wei, Daming; Edgar, James H.; Meyer, H.M.; wallache; edgarjhThe oxidation of group three nitride semiconductors is an important aspect in the fabrication of high power transistors with insulated gates. Gallium nitride (GaN) and its alloys (AlGaN) have electrical properties that are superior to silicon, thus resulting in better performance (greater efficiency, higher power, and higher frequency) in many electronic devices such as high electron mobility transistors (HEMT) and metal oxide semiconductor field effect transistors (MOSFET). Such devices will be greatly enhanced by adding a high quality electrically insulating layer, and this may be prepared by thermal oxidation. Thus, the dry thermal oxidation of polycrystalline GaN powder and GaN epitaxial layers was studied, over the oxidation temperatures from 800 °C to 1000 °C for up to 6 hours. The physical and chemical properties of the oxides were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) respectively. An amorphous oxide layer formed at 800°C, but polycrystalline Ga2O3 was detected at a temperature over 850°C. As the oxidation temperature was increased, the oxide surface becomes rougher. The thickness of the oxide forming on the GaN epilayer was calculated according to a depth profile plotted with XPS data. A very thin oxide layer was formed from 800°C to 850°C over 6-hour oxidation. The oxidation rate was controlled by an interfacial-controlled reaction mechanism at low temperatures (~800 °C) and diffusion controlled at high temperatures (1000 °C).Item Open Access Exploration of attitudes and behaviors of consumers with food allergies about dining out: a focus group study(2011-06-27) Lee, Yee Ming; Kwon, Junehee; em04; jkwonFood allergy is a public health issue as 12 million adults are having food allergies in the U.S. The objective of the study was to investigate attitudes and behaviors of consumers with food allergies about dining out using focus groups. All sessions were audio-taped, transcribed verbatim, and analyzed using NVivo Version 8.0. Seventeen participants participated in one of four focus groups in February 2010. Participants perceived cross- contact, hidden ingredients, and long communication chain in the restaurants as potential causes of food allergic reactions. Perceived barriers to provide allergen-free food were lack of training and awareness among employees. Participants perceived buffet and ethnic cuisine restaurants as risky dining places due to cross- contact and hidden ingredients. The participants preferred eating at national brand, chain restaurants since employees were well-trained about food allergies. Participants expected the servers to strictly follow the instructions given and they also felt the needs of regulations to protect people with food allergies. Participants wished to have the major allergens and listings of ingredients on the menus. Participants suggested people with food allergies to ask for clarifications from the servers while dining out, look up food allergy information online, bring Epi-pen with them, or pack their own snacks in case allergen-free food might not be provided. Results showed that consumers with food allergies experience many difficulties in restaurants due to restaurant employees' lack of knowledge and training regarding food allergy.Item Open Access Metabolism of azo dyes, methyl red and methyl orange by plants(2011-06-27) Kamat, Rohit B.; Davis, Lawrence C.; rohitbk; ldavisAzo dyes like methyl red and methyl orange are known to be major human carcinogens besides being water pollutants. These dyes are still a cause of concern in the developing nations due to their unrestricted usage. Laccases and peroxidases isolated from bacteria and fungi are presently being explored for decolorizing dyes. Whole plants have rarely been employed in degrading dyes. The goal of our work is to identify and characterize the groups of enzymes from plants involved in the breakdown of dyes. Hydroponically cultivated Arabidopsis thaliana were treated with 20 mg/L solutions of methyl red and methyl orange prepared at two pH values, 4.6 and 6.3 in the presence or absence of external hydrogen peroxide. Presence of peroxide at either pH does not accelerate the decolorization of the dyes. Plants assayed at pH 4.6 (methyl red-4.5 nmoles/hr; methyl orange-3.9 nmoles/hr) were found to degrade the dyes at the same rate as that observed for pH 6.3 (methyl red-4.2 nmoles/hr; methyl orange-3.5 nmoles/hr). Within three days the plants were able to decolorize 60% of both the dyes. A strong salt, 0.1M magnesium sulphate, has been found to extract nearly 30% of the total enzyme activity measured by ABTS [2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] and peroxide at either pH. The peroxidase activity as measured by ABTS color reaction is in ~1000 fold excess over observed degradation of methyl red or methyl orange. This suggests that the enzymes involved in the dye uptake might have low substrate affinity, or low reactivity with the dyes.Item Open Access Life history parameters of the rove beetle Atheta coriaria and efficacy against the fungus gnat Bradysia sp. nr. coprophila(2011-06-27) Echegaray, Erik; Cloyd, Raymond A.; eechegar; rcloydFungus gnats (Bradysia spp.) are major pests of greenhouse production systems in the USA. A number of biological control agents have been successfully used in dealing with fungus gnats, including the rove beetle Atheta coriaria, which is a predator that may regulate fungus gnat populations. Despite the evidence associated with its potential as a biological control agent there is no quantitative information available on efficacy of A. coriaria against the fungus gnat Bradysia sp. nr. coprophila. The overall objective of this study was to determine if A. coriaria is a viable biological control agent against fungus gnats under laboratory conditions. Life history parameters were evaluated based on visual observations: Total development time from egg to adult was 15.8 ± 0.39 days at 26°C. After one generation, 69.1 adults were obtained per female; the lowest number of adults per female was 39 while the highest number was 104. Female adult longevity was 47.8 days and the sex ratio was 1:1. A growing medium moisture content <60% may negatively influece adult survival. Efficacy against fungus gnat larvae was evaluated in petri dishes and deli squat containers using growing medium as a substrate, and different predator and prey densities. Although there were no significant differences in prey consumption among the different predator:prey ratios, there was a positive numerical response with higher consumption rates per adult observed at higher prey densities. Consumption rate was higher for second instar than third instar fungus gnat larvae.Item Open Access Pyrosequencing to determine the influence of fallow period on soil microbial communities in the Bolivian highlands(2011-06-27) Gomez, Lorena; Jumpponen, Ari M.; Gonzales, Miguel A.; Cusicanqui, Jorge; Valdivia, Corinne; Motavalli, Peter; Herman, Michael A.; Garrett, Karen A.; logomez; ari; mherman; kgarrettIn the Bolivian highlands (Altiplano; approx. 4000 masl), traditional fallow periods are being shortened in an effort to increase short-term crop yields, which may be at the expense of soil quality and plant health. Using 454-pyrosequencing and DNA-tagging, we characterized the response of the microbial community to (1) the length of fallow period and (2) the presence of Parasthrephia sp. and Baccharis sp. (both locally known as „Thola‟), considered beneficial to the maintenance of soil health in fallow fields in this region. The two study regions, Umala and Ancoraimes, differ in their soil characteristics, which may be a fundamental reason for the inherent differences in regional management practices. Soils in Ancoraimes have higher levels of organic matter, nitrogen and other macronutrients, which supported more diverse fungal communities (P<0.001). The presence of Thola after ten years of fallow had a positive effect on soil fungal diversity. Unexpectedly, the longer fallow periods were associated with lower fungal richness and diversity, perhaps because some fields with longer fallow periods were perceived by managers to have lower quality soils. Analyses of bacterial communities and fungal community composition are underway. Our results suggest that the drivers of microbial richness may be more complex than predicted by fallow period alone, and that plant cover may be important in conserving microbial communities.Item Open Access Energy-aware distributed tracking in wireless sensor networks(2011-06-27) Roseveare, Nicholas J.; Balasubramaniam, Natarajan; nickrose; balaWe consider a wireless sensor network engaged in the task of distributed tracking. Here, multiple remote sensor nodes estimate a physical process (for example, a moving object) and transmit quantized estimates to a fusion center for processing. At the fusion node a BLUE (Best Linear Unbiased Estimation) approach is used to combine the sensor estimates and create a final estimate of the state. In this framework, the uncertainty of the overall estimate is derived and shown to depend on the individual sensor transmit energy and quantization levels. Since power and bandwidth are critically constrained resources in battery operated sensor nodes, we attempt to quantify the trade-off between the lifetime of the network and the estimation quality over time. A unique feature of this work is that instead of merely allowing a greedy minimization of uncertainty in each time instance, the lifetime of the wireless sensor network is improved by incorporating a heuristic scaling on the operating capability of each node. This heuristic in turn depends on the remaining energy, equivalent to the past history of power and quantization decisions. Simulation results demonstrate the quality of the state estimate as well as the extended lifetime of the network when power and quantization levels are dynamically updated.Item Open Access How does visual attention differ between experts and novices on physics problems?(2011-06-27) Carmichael, Adrian; Larson, Adam; Gire, Elizabeth; Loschky, Lester C.; Rebello, N. Sanjay; adrianc; adlarson; loschky; srebelloEye movement data has been shown to enhance our understanding of student's problem solving behaviors in physics and also help us identify differences between novices and experts. In this study we compare the eye movement data of experts and novices using introductory conceptual physics problems. The problems chosen all utilize concepts that have an inherent spatial component in their visual representation. To become aware of the critical concept in each problem, the solver must attend to that spatial component of the figure. To gain additional information about how the experts and novices answered each problem, we interviewed the participants about the reasoning process they used and compared these answers to the eye movements. We will discuss our results from interviews as well as eye-tracking data from both experts and novices.
