2021 award winners
At GPSA Research Exposition
Agricultural & natural resource sciences
First place
Karansher Sandhu
Combining genomic and high-throughput phenotyping information for predictions in a wheat breeding program
Genomics and high throughput phenomics have the potential to revolutionize the field of wheat (Triticum aestivum L.) breeding. Genomic selection (GS) has been used for predicting various quantitative traits in wheat, especially grain yield. However, there are few GS studies for grain protein content (GPC), which is a crucial quality determinant. Incorporation of secondary correlated traits in GS models has demonstrated to improve accuracy. The objectives of this research were to compare performances of single and multi-trait GS models for predicting GPC and grain yield in wheat and identification of the best stage for collecting secondary traits. We used 650 recombinant inbred lines from a spring wheat nested association mapping (NAM) population. The population was phenotyped over three years (2014-2016), and spectral information was collected at the heading and grain filling stage. The ability to predict GPC and grain yield was assessed using secondary traits, univariate, covariate, and multivariate GS models for within and across cycles predictions. Our results indicate that prediction accuracy increased by an average of 112% for GPC and 120% for grain yield by including secondary traits in the models. Spectral information collected at heading was superior for predicting GPC, whereas grain yield was more accurately predicted at grain filling stage. Green normalized difference vegetation index (GNDVI) showed the most significant improvement in the prediction of GPC either used individually or with multiple indices in the GS models. An increased prediction ability for GPC and grain yield with the inclusion of secondary traits demonstrates the potential to improve the genetic gain per unit time in wheat breeding.
Second place
Vishnutej Ellur
Investigating the roles of plant polygalacturonase inhibiting proteins (PGIPs) against fungal pathogens
During the early stages of the disease development, fungal pathogens produce polygalacturonases (PGs) to degrade pectin in the plant cell wall, thus initiating infection. In response, plants produce polygalacturonase inhibiting proteins (PGIPs) to inhibit pathogen PGs. The interaction of plant PGIPs with fungal PGs not only limits the destructive capacity of PGs but also promotes the production of oligogalacturonides that triggers plants innate immunity by acting as damage-associated molecular patterns (DAMPs). The ability of PGIP to protect plants from fungal, oomycetic, and bacterial pathogens has been reported by recent studies, and the use of PGIPs can be an environmentally safe alternative for containing plant diseases. The current research focuses on three chickpea PGIPs (CaPGIPs) and their role in the defense against four fungal pathogens (Ascochyta rabiei, Botrytis cinerea, Fusarium oxysporum f.sp. ciceris, Sclerotinia sclerotiorum). Our computational analysis predicts that CaPGIPs can potentially interact with pathogen PGs, so we looked at the CaPGIPs gene expression pattern using real-time quantitative (RT–qPCR). Results showed that when infected by the four fungal pathogens, CaPGIPs were differentially expressed in resistant and susceptible cultivars, and a higher expression was reported in the resistant host for all CaPGIPs which indicates CaPGIPs ‘s involvement in defense. Exogenous application of phytohormones such as abscisic acid, auxin, methyl jasmonate, and salicylic acid has substantially induced CaPGIPs expression, indicating that CaPGIPs are involved in disease resistance pathways. These findings show the effectiveness of CaPGIPs in controlling fungal diseases and could be promising candidate genes for the transgenic breeding for disease-resistance.
Third place
Dowen Jocson
Use of vibrations as mating disruption in Pear Psylla (Cacopyslla pyricola)
Integrated pest management (IPM) aims to reduce the use of pesticides and develop more effective ways of reducing pest populations without harming beneficial species. Recent technological developments have created opportunities for scientists to understand the fundamental biology of pest species to better develop IPM strategies. One of these advances is our ability to “listen” into insect communication, specifically, substrate-borne vibrational communication. Like most insects, the pear psylla, Cacopsylla pyricola, can communicate using substrate-borne vibrations to search for and attract mates. This channel of communication can be exploited to disrupt mating behavior and reduce mating rates, potentially decreasing population for the next generation. In this study, I have set up playback devices that mimic substrate-borne vibrations on the stems of pear plants. I played back male mating signals to a set of pears psylla rearing cages to exhibit competition. In another set, I played back white noise to cover a spectrum of frequency as a positive control, while another set received no playback. At the end of four weeks, I looked at the number of offspring produced in each treatment to determine efficacy of vibrational playbacks on reducing mating rates. I saw that the white noise and male signal playbacks were more effective at reducing numbers of offspring compared to having no playback at all. This implies that there is a potential in exploiting the vibrational communication channel in pear psylla as a pest management tool.
Fourth place
Femi Peter Alege
Co-pelletization of dairy manure compost and fishmeal for soil amendment and environmental management
PRINCIPAL TOPIC
Studies on improving the utilization, transportation, and storage of animal manure nutrients are critical to mitigating potential adverse environmental impacts of excess manure nutrients produced in regions with high concentrations of animal production. This study investigated the potential of fishmeal for improving manure compost value and the effects of co-pelleting both products on the pellets’ properties.
METHOD
The percentage pre-pelleting blending ratio of fishmeal ranged from 0 – 20%. Based on previous studies, pellets were produced at the moisture content of 21% (w.b.), with 6-mm, 8-mm, and 10-mm dies. The effects of fishmeal blending were evaluated against the pellets’ unit and bulk densities, recovery, durability, and nutrients (total-N and P2O5) concentration of the resulting pellets. Scanning Electron Microscopy (SEM) images were used to assess the effect of fishmeal blending on pellets’ porosity and surface smoothness. Relevant properties and nutrient analyses were determined following established and standard protocols.
RESULTS/IMPLICATIONS
For the three die sizes, results showed positive correlations between fishmeal content and unit density (r≥0.93 for 6-mm and 8-mm dies), total-N (r≥0.98), and P2O5 (r≥0.98). Inverse correlations were observed between blending ratio and pellets durability (r≤ -0.98), and pellet length (r≤ -0.91 for 6-mm and 8-mm dies). The effects of fishmeal addition on pellets recovery and diameter were not significant, while effects of die size also varied with different quality criteria. Overall, the study revealed nutrient value and transportability were improved when: (1) compost was blended with small proportions of fishmeal, and (2) smaller dies were used.
Arts & education sciences
First place
Erica Doering
“Can’t you see that I’m getting bored?”: College student’s conceptualization of boredom
PRINCIPAL TOPIC
Almost everyone experiences boredom, but researchers do not agree on how best to measure it. Boredom serves as a signal telling us the current situation is unsatisfying and may be associated with negative outcomes (i.e., overeating, substance use) and positive outcomes (i.e., greater creativity, improved productivity). Prior research on causes and correlates of boredom used varying conceptualizations such that researchers have called for a standard definition to “guide…construct development and boredom measurement” (Vodanovich & Watt, 2016, p. 220). As a first step, we need an emic, or insider, perspective of boredom currently not provided by measurement scales nor lab experiments. The current study uses qualitative data to understand how college students conceptualize and, presumably, experience boredom.
METHOD
The sample includes undergraduate students (N=480, Mage=20.5, 84% female) who completed an online survey. Participants were given an open-ended prompt of “What comes to mind when you see the word boredom?” and asked to list up to ten word/phrases. Responses were cleaned and analyzed using the constant comparative coding method by the primary author and a research assistant. The coding process and categories were reviewed by two additional researchers for triangulation and trustworthiness.
RESULTS/IMPLICATIONS
Seven themes emerged, the top three of which were behaviors (e.g., sleeping, eating), motivation (e.g., lazy, disinterested), and cognition and emotions (e.g., sad, depressed). Findings illustrate how college students view boredom and contributes to the understanding of contextual and individual boredom factors. Results hold implications for future approaches to promote healthy boredom coping to mitigate negative consequences.
Second place
Sarah C. Boland
Examining ethnicity as a moderator of the relation between pre-parent factors and actual/perceived knowledge of ASD
PRINCIPAL TOPIC
There is little known about parenting knowledge in pre-parents, as most studies focus on those that are already a parent. Additionally, evidence suggests there may be ethnic disparities in age of diagnosis for children with autism spectrum disorder (ASD) due to caregivers’ lack of awareness of early signs of neurodevelopmental delay (Mandell et al., 2009). The present study aimed to evaluate how prior experience with children, undergraduate education, and family SES may relate to pre-parents’ actual and perceived ASD knowledge and how ethnicity may moderate those relations.
METHOD
Participants were 221 undergraduate students who identified as pre-parents (i.e., have no children but plan to have children in the future). They completed questionnaires via Qualtrics including A Survey of Knowledge of Autism Spectrum Disorder, assessing perceived and actual ASD knowledge, and a demographic questionnaire, which included ethnicity, experience with children, and previous enrollment in specific Psychology undergraduate classes.
RESULTS/IMPLICATIONS
Ethnicity, family SES, and child experience explained significant variance in participants’ ASD knowledge. The lack of a contribution from classes suggests that Psychology curriculum may need to place a heavier emphasis on neurodevelopmental differences. Moderated multiple regression analyses examining the interaction between ethnicity and predictors indicated that the positive relation between child experience and perceived or actual ASD knowledge only emerged for White participants, not Non-White participants. This interaction suggests that Non-White participants may rely on other factors when acquiring knowledge of ASD. The findings may provide clinical implications to how pre-parent knowledge of neurodevelopmental disabilities could enhance early diagnoses.
Third place
Elizabeth Purser
Flourishing among college students and impacts of substance use
PRINCIPAL TOPIC
Flourishing is an individuals’ perceptions of their relationships, self-esteem, and outlooks on their life and associated with psychological well-being (Diener et al., 2010). The association between flourishing and substance use in adolescents and young adults is mixed, with some studies finding no association (Low, 2011) and others finding it is associated with a lower chance of cannabis use (Butler et al., 2019). The current study aims to understand the association between flourishing and substance use among college students.
METHOD
An online survey was completed by a sample of undergraduate students (N = 480, Mage = 20.5, 84% female) measuring their perceived flourishing on an 8-item scale (Diener et al., 2010) as well as frequency and type of substance use over the past month and year. Multiple regression analyses were used to determine the association between yearly and monthly tobacco, alcohol, and cannabis use and flourishing among college students.
RESULTS/IMPLICATIONS
Results indicated a significant positive association between yearly alcohol use and flourishing, t(431) = 2.05, p = .04; age, t(431) = 2.79, p = .006; and living in Greek housing, t(431) = 3.78, p < .001, controlling for race/ethnicity and gender identity. Tobacco and cannabis use were not significantly associated with flourishing. Participants who reported more frequent alcohol use appeared to have high levels of flourishing, suggesting that high flourishing may be a protective factor against negative outcomes of alcohol use. Future research is needed to determine how this relationship is associated with other outcomes, such as school success.
Fourth place
Lindsay McCoy
Why collaborative apparel consumption is gaining popularity? An empirical study of U.S. Gen Z consumers
Apparel rental, also known as collaborative consumption, has created an innovative and popular business model allowing consumers to focus on using their products instead of ownership. A recent CGS Survey (2019) revealed that sustainability is driving demand and customer loyalty in the U.S. Among all generations, Gen Z adult consumers (born 1997 to 2002) lead the way as eco-friendly shoppers and are the new driving force for retail growth. To better understand the emerging popularity of apparel rental services among Gen Z adult consumers, this study aimed to identify the factors significantly influencing their intention to use apparel rental services. First, a research model was proposed building on the Theory of Planned Behavior (TPB). Second, the psychometric properties of the proposed model were examined using the gathered survey data. Third, the effects of significant factors on U.S. Gen Z consumers’ intention to use apparel rental services were determined. 362 eligible responses were gathered for data analysis and hypothesis testing. Attitude, subjective norms (SN), perceived consumer effectiveness (PCE), past environmental behavior (PEB), and fashion leadership (FL) significantly affected U.S. Gen Z consumers’ intentions to use apparel rental services. There were no significant differences between demographic variables in regard to their intentions to use apparel rental services. Environmental knowledge (EK), fashion leadership (FL), and need for uniqueness (NFU) positively shaped Gen Z consumers’ attitude toward using apparel rental services. The results provide retailers with a better sense of how to attract Gen Z consumers to apparel rental services.
Business, communication, & political sciences
First place
Demi Shenrui Deng
What people TikTok (Douyin) about influencer-endorsed short videos? An exploration of gender and generational differences
This study aims to understand social media users’ feedback and need on influencer-endorsed wine short video messaging on the most popular platform – Douyin (TikTok), relying on message interpretation process (MIP) framework and also identify segmentation differences from gender and the generational cohorts (Gen Z and Gen Y). Topic modeling, sentiment analysis, content analysis, and quantitative analysis were utilized to decipher 24,458 online comments embedded in 81 wine short videos from the top 30 social media influencers focusing on wine product and consumption experience messaging. The results demonstrate social media users are most inclined to respond to product-related topics, followed by the influencer, emotional, alcohol drinking intent, behavioral, and skepticism. Meanwhile, the findings also revealed that the female group was more likely to engage in influencer topics, whereas the male group contributed more to product subjects. Gen Z cohort involved more themes about alcohol drinking intent, while Gen Y contributed more to skepticism. The findings provide hospitality and wine practitioners, social media influencers, and brand sponsors with suggestions for how best to strategically market their offerings to meet customers’ demands, including different segmentations. This study is the first to grasp the previous, current, potential customers’ response and requirements on this newly emerged influencer marketing strategy.
Second place
Kamal Ahmmad
Resistance or revolution: The role of consumer characteristics, consumer knowledge, and label information on the acceptance of cell-based meat
PRINCIPAL TOPIC
Consumers have default reluctance to adopt novel and unfamiliar food technologies. This research examines factors associated with consumer resistance to cell-based meat product, a promising solution to environmental, ethical, and health concerns associated with meat consumption. Considering the current policy and marketing debates centered on cell-based meat product, we examine the role of product cues (e.g., names, label information), consumer knowledge, and food technology neophobia (FTN) on the evaluation of cell-based meat products in retail settings.
METHOD
A total of four experiments were conducted to examine the perceptions and evaluations of cell-based meat. We manipulated product-related cues, and consumer knowledge and tested their effect on product perceptions (e.g., attitude, healthfulness, and expected taste). Using analysis of variance and conditional PROCESS analysis, we examined how product cues and consumer knowledge interact with FTN in influencing product perceptions and purchase intention.
RESULTS/IMPLICATIONS
In study 1a (IAT) and study 1b, we demonstrate that consumers evaluate cell-based meat negatively compared to conventional meat when all product related cues are controlled. Study 2 showed that using semantically superior product names eliminate resistance which increases positive perceptions and purchase intentions. Study 3 further demonstrates the role of safety claims on the product labels, consumer knowledge, and consumers’ level of FTN. Specifically, we show that product cue manipulation interacts with consumers’ FTN to buffer against the resistance. Overall, our research resolves important policy debates and provide implications for marketers and retailers. This research also contributes to activation theory, consumer inferential processing, and resistance framework.
Third place
Muzi Liu
The role of salespeople’s behavior in credit management in small business
Despite the economic importance of small businesses to the US economy and well-being, these firms are often exposed to a greater level of credit management problems (Paul and Boden 2011; Peel, Wilson and Howorth 2000). If credit management has not been done properly, firms can be at risk of receiving late payments from customers. Due to the lack of financial means to exert proper institutional measures to manage credit control, many small businesses rely on their salespeople to be responsible for checking customers’ creditworthiness negotiating payment terms. Although practitioners have widely acknowledged that having salespeople responsible for credit is common among many small businesses, academic research has yet to examine salespeople’s role in credit management. Little is known about the antecedents and consequences of salespeople’s credit management behavior. To fulfill this gap, the current research aims to introduce salesforce control systems as antecedents of salespeople’s behavior in credit management. This relationship is expected to have an effect on customers’ late payment. This study will collect data from full-time-employed salespeople from US small businesses in the Business-to-Business (B2B) space (i.e., employee size < 50). An online survey will be administered via Centiment, a global online survey service platform, to test the hypotheses. This research contributes to the sales literature by broadening the understanding of salespeople’s role in credit management. It offers a new perspective for sales researchers and small business managers to examine the practical approaches to help reduce customers’ late payment.
Engineering & environmental sciences
First place
Haneen Abusharkh
Gallic acid and stretching promote extracellular matrix production in human cartilage
Articular Cartilage (AC) is an avascular protective soft tissue that covers bones in articulating joints. The avascular nature of AC makes its access to oxygen and nutrients limited and reduces its ability to regenerate after trauma. AC degenerates gradually after injury leading to osteoarthritis (OA), the most common form of arthritis worldwide. Although OA was categorized as “non-inflammatory” for a long time in contrast to rheumatoid arthritis, recent studies reconsidered the definition after observing immune responses and apparent symptoms of inflammation, e.g., swelling, in the joints of OA patients. Another critical symptom of inflammation is the upregulation of catabolic genes that destroy the extracellular matrix (ECM) proteins of cartilage, making cartilage mechanically weaker. In this work, we studied the use of of biochemical and mechanical factors for reducing the inflammation of human articular cartilage cells, chondrocytes (hAChs). To do that, human chondrocytes were pooled, taken from four different OA study participant tissues removed after total knee arthroplasty. hACHs were cultured within two separate groups, a static group and a group mechanically stimulated by stretching. Group samples were either treated with standard culture medium as a negative control or aa nutraceutical supplemented medium as the experimental group. Nutraceuticals were used because of their potential for downregulating catabolism. Then, we monitored hACh production of healthy cartilage extracellular matrix proteins, total collagen (COL), and total glycosaminoglycan (GAG), as indicators of inflammation reduction. Our results show that simultaneous stretching and nutraceutical supplementation increased COL and GAG content by more than 11- and 21-fold, respectively.
Second place
Umar Farooq
Accelerated potential evaporation driven by vapor pressure gradient
Climate change is altering global hydrological cycles as indicated by potential evaporation (E) trends. While these trends are widely studied using pan E, the near constant atmospheric vapor pressure deficit (VPD) and decrease in solar irradiance are considered its key driving parameters. However, the negligence of thermal inertia and ice phenology in evaporating pans inhibit there use as proxies of potential E. Lake E is only controlled by climate forcings; therefore, lakes provide ideal spots to study spatiotemporal variations in potential E and its environmental controls. Here using the lake simulator in Community Land Model (CLM4.5), we provide an estimate of change in global lake E from 1951-2016 and its driving parameters. The global lake E loses its strength by 0.41 mm yr-2 during 1950-1980. However, since 1981, contrary to decrease in solar irradiance and VPD, it is accelerating by 0.67 mm yr-2. The increase in vapor pressure gradient (VPG), difference between lake surface vapor pressure and air vapor pressure, outpaced the declining VPD trend and explains 52% of the interannual variability in E. The correlation gets stronger at seasonal timescale and VPG explains up to 67% of variability. Our findings suggest that in hydrological modeling the VPG should be considered instead of VPD to determine potential impacts of climate change on global hydrological cycles.
Third place
Shichao Ding
Single-atom catalysts as artificial enzymes for biomedical applications
PRINCIPAL TOPIC
Natural enzymes are one of the most important compounds in biomedical applications. However, their wide application is limited by expensive production cost and instability in complex conditions like high temperature or harsh pH environment. It is urgently to develop artificial enzyme alternatives for natural enzymes with high stability and low-cost in biomedical applications.
METHOD
We designed artificial enzymes using a single-atom architecture that was able to work as efficiently as natural enzymes. The artificial enzyme, called a nanozyme, is made of single iron atoms embedded in nitrogen-doped carbon nanomaterials (with Fe-Nx active site), which mimic the active site of heme enzymes from an atomic/molecular structure perspective. The single-atom structure was fully characterized, and enzyme-like properties were evaluated. For investigating practical applying ability, electrochemical sensors, immunosorbent assays, and intercellular nanoprobe based on single-atom catalysts were developed for H2O2-based biosensing and bioimaging applications.
RESULTS/IMPLICATIONS
The artificial enzyme based on a single-atom catalyst that we created has a similar active site structure as a natural enzyme with remarkable enzyme-like activity for H2O2, which paved the way for high-sensitive biosensing. The single-atom artificial enzyme was also more robust than natural enzymes, which can degrade in acidic environments or in high temperatures. Their unique electronic/geometrical have significant advantages in biocatalytic activity, stability, and selectivity, which show massive potential in substituting natural enzymes for various biomedical applications.
Fourth place
Yonas Gezahegn
Dielectric properties of water relevant to microwave-assisted thermal sterilization and pasteurization of packaged foods
PRINCIPAL TOPIC
In microwave systems design and operation, the dielectric (electrical) properties of the non-metallic components must be considered and modeled. These properties influence the electric field distribution and microwave power absorption. Hence, analyzing the dielectric properties of circulation water, used as a heating medium of packaged foods, in the industrial microwave-assisted thermal sterilization (MATS) and pasteurization system (MAPS) is vital.
METHOD
This research aimed to study a reverse-osmosis purified and tap circulation waters dielectric properties in 150 – 2,500 MHz from 23 – 120 ℃and their influence on microwave power penetration depths in the MATS and MAPS. The dielectric properties were measured with an open-end coaxial probe method with a custom-built temperature-controlled test cell.
RESULTS/IMPLICATIONS
Dielectric constants of purified and tap waters significantly decreased (P < 0.05) with increasing temperature, while their loss factors increased (P < 0.05) with increasing frequency and decreasing temperature, except tap water below 600 MHz. The 915 MHz microwave power penetration depth in purified water was 399 and 457 mm at 90 and 120 ℃, respectively, but it was reduced to 161 and 140 mm in tap water. The microwave power loss in 27 mm deep purified water was 8% and 12% less than in tap water at 90 and 120 ℃, respectively. Using purified circulation water in the MATS and MAPS can significantly improve the efficiency of microwave energy into packaged foods. Furthermore, the dielectric properties data can be used by process engineers with relation to industrial microwave heating systems and domestic microwave ovens. Keywords: Dielectric properties; microwave heating; pasteurization; purified water; sterilization; tap water.
Fifth place
Wrya Mohammadi
Activating nitrogen atom for ammonia synthesis: nitridation of manganese
PRINCIPAL TOPIC
Affordable synthetic ammonia (NH3) enables the production of about half of the food we eat. Besides, NH3 is the most promising clean energy battery for the future. However, ammonia is almost exclusively produced based on fossil fuels, under high pressure (>200 bar), and requires large capital-expenses. This study aimed to design a method to synthesis ammonia at atmospheric-pressure which greatly simplifies processing, requires lowers capital expense, and may allow rapid startup/shutdown when using intermittent renewable energy. The success of such technologies relies on how nitrogen atom (N) is supplied to react with a hydrogen atom (H). So, this project focused on forming nitride and N mess transfer in the NH3 synthesizing process.
METHOD
In this investigation, we synthesized the NH3 based on a thermochemical process method. Manganese (Mn) is used here to activate dinitrogen (N) in the first step by forming bulk Mn-nitride, then synthesizing ammonia in the next step by contacting nitride with gaseous-hydrogen. The morphology and the growth kinetics of Mn nitride layers by exposing Mn particles and multi-micron Mn plates to gaseous dinitrogen at 700°C and atmospheric pressure.
RESULTS/IMPLICATIONS
Morphology changes detected by SEM, along with mass balances, and EDX yielded a coherent picture of nitridation of solid Mn by exposure to gaseous dinitrogen at atmospheric pressure and 700°C. The evolution of three distinct regions with time was quantified and reduced to a simple design equation. 3.52±0.22 kg ammonia per 1 ton Mn can be harvested.
Medical & life sciences
First place
Garry Smith
Molecular mechanism of leiomodin acting as a leaky cap at the pointed end of thin filaments
PRINCIPAL TOPIC
There is no consensus on how sarcomere thin filaments, actin polymers stabilized by tropomyosin (Tpm) polymers, are maintained at mature length. Proper thin filament length is essential for proper muscle contractions. Leiomodin (Lmod) and tropomodulin (Tmod), sharing a similar domain structure of actin- and Tpm-binding sites, are thought to compete for binding at the pointed end of the thin filament. When Lmod is bound, actin monomers can be added slowly. When Tmod is bound, actin monomers can neither be added nor subtracted.
METHOD
A lack of structural data of either Lmod or Tmod binding to Tpm has led to debate over this mechanism. With our recently obtained 3-dimensional atomic structure of the binding interface between Lmod and Tpm, and with existing structures of Lmod and Tmod actin-binding sites, we created a model of Lmod assembly at the pointed end of thin filaments, joining binding sites with links developed by molecular dynamics simulations.
RESULTS/IMPLICATIONS
Based on the model, we propose a molecular mechanism of Lmod function as a leaky cap. According to this, actin binding site 1 (ABS1) in Lmod dissociates from its actin protomer to allow an actin monomer to bind, after which polymerization can occur. Once seven monomers have been added to each side, a new Tpm protomer binds the newly-added actin and to the previous Tpm protomer, competing with and displacing Lmod’s single Tpm-binding site. ABS1 in Tmod, on the other hand, cannot dissociate to allow such polymerization because it is fixed in place on either side by Tpm-binding sites.
Second place
Amninder Singh Sekhon
Rapid identification of single and mixed strains of Listeria monocytogenes and Escherichia coli O157: H7 in dairy products using an affordable custom assembled hyperspectral imaging system
PRINCIPAL TOPIC
With increased incidences of foodborne diseases and outbreaks in recent past, there is a dire need for pathogen detection and identification system which is rapid, reliable, and inexpensive. Hyperspectral imaging (HSI) is one such novel technique which amalgamates imaging and spectroscopy methods to capture both spatial and spectral features of bacterial cells. The HSI system built by us utilizes spectral signatures of respective pathogens for rapid identification.
METHOD
This study was designed as a randomized complete block design with 3-replications. Three strains of Listeria monocytogenes (LM) and Escherichia coli O157: H7 (EC) were used as either single or mixed strains. Sorbitol MacConkey and PALCAM agars were used as selective growth media for EC and LM, respectively. Freshly prepared single and mixed strains of respective pathogens or inoculated dairy products were streaked for isolation on respective media. A single colony of desired pathogen was selected and mixed in 1-ml of HPLC grade water and vortexed for 1-minute. Subsequently, using a sterile loop, slide preparation was performed, and then analyzed using HSI setup. Acquired images were imported into ENVI software and 3-regions of interest (ROI) were selected for each image to obtain hyperspectral signatures. Cells were classified by their hyperspectral signatures as either L. monocytogenes or E. coli O157:H7 using K-nearest neighbor (KNN) and cross validation technique in R-software
RESULTS/IMPLICATIONS
Classification accuracies of 58.97 and 61.53 percent were obtained for EC and LM, respectively. This study sets the first step towards developing reference library for the hyperspectral signatures of pathogens.
Third place
Jennifer Madigan
Perinatal hair cortisol concentration linked to psychological well-being over time in women who experience birth complications
Animal models show that physiological stress experienced by women during the perinatal period can affect maternal well-being, birth outcomes, and the post-natal development of offspring. However, the relationship between elevated cortisol and psychosocial stress during this period is not well understood. Hair cortisol concentration (HCC) has emerged as an indicator of chronic physiological stress in humans, but the relationship between psychosocial measures of stress and anxiety and HCC during the perinatal period or birth experiences is unknown. We investigated the relationships between HCC during the 3rd trimester (n=56) and 6 months after birth (n=50), measures of anxiety/perceived stress, and birth outcomes of women (82.76% Caucasian, 17.24% other race, 22% had birth complications). We found that mean HCC during the 3rd trimester was twice as high in women who had birth complications (t =2.10, P = 0.04), and HCC was positively correlated with state and trait anxiety and perceived stress only in women who experienced birth complications (r = .46-.54, all complication x score interactions P < 0.05). HCC at 6 months was positively correlated with anxiety/perceived stress scores measured after birth, and these relationships were stronger in women reporting birth complications and perinatal trauma (2 months: r = .65-.89, 6 months r = .47-.57). These findings suggest self-reported measures of anxiety and stress are positively associated with circulating cortisol levels throughout the perinatal period, especially in women experiencing birth complications, and the measurement of anxiety/perceived stress and HCC during pregnancy may help identify women at risk of birth complications.
Fourth place
Jerrisa Ching
A targeted literature review on the implications of Frog Virus 3 (FV3)-like Ranavirus emergence in three-toed box turtle (Terrapene mexicana triunguis) populations in Saint Louis, Missouri
Iridoviruses in the genus Ranavirus are emerging threats to numerous taxa. Frog Virus 3 (FV3)-like ranaviruses specifically cause mass mortality events in some reptile species, presenting a conservation threat. Three-toed box turtles (Terrapene mexicana triunguis) are classified by the International Union for Conservation of Nature as vulnerable and declining, due in part to emerging infectious diseases. However, there is currently no information on FV3-like ranaviruses in three-toed box turtles at the individual or population level. A targeted literature on FV3-like ranaviruses in closely related box turtle species was performed to evaluate potential implications of viral emergence in three-toed box turtles. Relevant peer-reviewed literature was obtained through searches in the Washington State University SearchIt Libraries and Google Scholar search engines and consultation with experts from Washington State University College of Veterinary Medicine and Saint Louis Zoo Institute for Conservation Medicine. The review encompassed current biomedical, epidemiologic, and ecologic information on FV3-like ranaviruses in other Terrapene species in adjacent geographic regions to Missouri. Our targeted literature review revealed that FV3-like ranaviruses has caused immense mortality events in Terrapene species with ranges adjacent to or overlapping with the three-toed box turtle. Based on this and the common pathogenicity, clinical manifestations, and environmental factors associated with FV3-like ranaviruses in these Terrapene species, there is a strong potential for emergence and population level consequences in three-toed box turtles. Surveillance and focused epidemiologic studies on FV3-like ranaviruses in three-toed box turtles are needed for early detection and effective mitigation of this potential conservation threat.
Fifth place
Colin McDowell
The fitness cost of tetracycline resistance
Antibiotic resistance is an energetically expensive defense for bacteria, resulting in a potentially significant cost when unnecessarily expressed. Gene regulation is a key mechanism to prevent unwarranted expression of antibiotic resistance. This raises the possibility that bacteria can be “tricked” into expressing resistance genes when they are not required, thereby degrading the competitive abilities of antibiotic-resistant bacteria. Prior work found that tetracycline-resistant Escherichia coli were less competitive in the presence of degraded tetracycline, but the experiment relied on a genetic deletion that included multiple genes, and hence the results were confounded. Here we cloned the two critical genes in question, tetB and tetR, and directly assessed their impact on fitness using tetracycline-resistant (SSuT6) and -susceptible (SSuT6ΔTn10) strains of E. coli. Tet(B) is a proton-motive efflux pump that removes tetracycline from the cell, while TetR is a regulator protein for tetB. The two genes of interest were cloned into a low-copy number plasmid and were transformed into the SSuT6ΔTn10 strain. To date, we have recovered the tetracycline-resistance phenotype for the SSuT6ΔTn10 strain, consistent with successful transformation. Sequencing confirmation is underway, which will be followed by experiments to assess how TetB impacts the fitness of the SSuT6ΔTn10 strain relative to the uncomplemented strain in the presence of a degraded tetracycline compound capable of inducing expression of tetB but without conveying antibacterial effects.
Physical & social sciences
First place
Jessica Carder
Stochastic biophysics of human Aquaporin-4: A protein tracking study
PRINCIPAL TOPIC
Aquaporin-4 (AQP4) is an integral water channel protein located in the plasma membrane of astrocyte cells in the central nervous system (CNS) and helps regulate water-ion homeostasis. Some isoforms of AQP4 further order themselves into aggregates known as orthogonal arrays of particles (OAPs).AQP4 exists in two main isoforms, M1 and M23, with M23 being the isoform that favors stabilization by aggregation into OAPs. What role these OAPs play in the membrane of cells is still largely unknown.
METHOD
Through a collaboration with the Nicchia group from the University of Bari, techniques have been developed to isolate and express the M23-AQP4 isoform in insect cell lines in its authentically folded state. This study takes natively folded AQP4 aggregates and incorporates them in a supported lipid bilayer CNS biomimetic, which have been characterized using fluorescence recovery after photobleaching (FRAP). Using single molecule fluorescence microscopy, we can observe the interactions of AQP4 proteins with the surrounding lipid environment and discover how different environmental cues effect OAP assembly kinetics and equilibrium states.
RESULTS/IMPLICATIONS
Through this study, we were able to track the protein temporally and physically watch the proteins interact within the bilayer. Using single molecule analysis, protein superstructure can be determined, and from this we concluded that there are indeed remarkably interesting interactions happening with this protein, and that AQP4 tends to assemble and disassemble on their own with no outside interactions. This is the foundational work that will lead to future studies exploring AQP4 mechanics under different environmental conditions.
Second place
Dalton Glasco
Development of a new method for ion-selective electrode fabrication utilizing 3D printing
This research develops a new method for ion-selective electrode (ISE) fabrication by utilizing an additive manufacturing technique, 3D printing. ISE use has become widespread and is routinely used in settings ranging from medical, agricultural, environmental, etc. With efforts to modernize the conventional fabrication method the use of 3D printing provides the following benefits over previously reported methods: (i) reduced membrane fabrication time, (ii) ability to precisely control thickness of membrane, and (iii) cost effective mass production. Here we show proof of concept demonstrations for both cation and anion selective ISEs. Furthermore, we highlight the scope of our approach and demonstrate the fabrication of both liquid and solid-contact ISE configurations. Results obtained with 3D-printed ISEs are consistent with to data presented in literature for ISEs fabricated using conventional methods. Analytical characteristics such as: Nernstian response, linear range, and stability will be discussed. With the increasing need for robust, reliable and cost-effective devices for point-of-care applications in fields such as pharmaceuticals, agriculture, and medical diagnostics, our approach has the capabilities to easily translate ISEs into point-of-care devices for widespread analysis.
Third place
Valda Black
Archaeology and social change: Inka imperial rule over the Chanka
An empire expanding into a previously established community can have significant impacts on the identity and culture of the conquered. The degree of imperial influence can vary depending on negotiations set into place between the invaders and native communities. A prominent example of these negotiations occurred in the prehistoric Andean highlands when the Inka rose to power during the Late Horizon (LH, AD 1400-1532). One area of social interactions the Inka targeted when incorporating communities into the empire was the alteration of their ancestor associations and behaviors, which makes studying burial contexts a key part of investigations into Inka imperial influence. This project focuses on the Chanka, a culture that developed during the Late Intermediate Period (LIP, AD 1000-1400) and were known infamously by the Inka as a group of warriors they conquered in battle before expanding into the rest of the Andes. However, archaeological evidence found at the site of Sondor, in the Andahuaylas region of Peru, shows a different type of relationship between the Chanka and Inka during the LH. Sondor has Chanka style burials and ceramics, mixed with Inka ceramics and various styles of burials. These findings go against contemporary local cultural understandings and attachment to Chanka ancestors, which means the findings must be published with local beliefs in mind. This paper will present the detailed findings from excavations at Sondor, and how they can be framed in a narrative that fits contemporary attachments to Chanka heritage, while staying scientifically accurate.
Fourth place
Angelo Brown
The impact of peacekeeping missions for female police officers
PRINCIPAL TOPIC
In 2009, the United Nations initiated an endeavor to expand the number of female police officers deployed with the United Nations Police (UNPOL). Currently, female UNPOL officers come from over 60 different countries. This presentation examines the lived experiences of these officers and how their race, culture, gender, and class affect their perceptions of their deployment and reintegration to their home countries.
METHOD
The data was derived from semi-structured interviews of UNPOL officers from fourteen different countries. The interviews of 20 female police officers were compared with the interviews of 20 male officers. The officers were asked questions related to how their gender and other attributes impacted their experience before, during, and after their deployments.
RESULTS/IMPLICATIONS
The analysis of the UNPOL officers illustrate vital issues faced by female officers, including issues in 1) disparities in treatment due to race, class, and gender; 2) interpersonal relationships with family, locals of host nations, and colleagues; and 3) officers’ physical, mental, and emotional health throughout the deployment process. Male and Female officers expressed that the female officers were more likely to be harassed and disrespected by the locals and by their UN colleagues. The officers also expressed female officers’ ability to provide better support and connection to the community, especially for the females and youth of the host-nation.