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Showcase Abstract 2020

Licensed to Silence: Search for the Host Defense Silencer in Cassava Torrado-like Virus

Licensed to Silence: Search for the Host Defense Silencer in Cassava Torrado-like Virus

Primary author: Jenyfer Jimenez
Co-author(s): Ying Zhai

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Cassava (Manihot esculenta Crantz, Euphorbiaceae) is an important staple food crop for Africa, Asia and Latin America. Cassava torrado-like virus (CsTLV, Family Secoviridae), is found in mixed virus infections associated with severe disease symptoms in leaves and roots of CsTLV, a major viral pathogen of cassava, has been reported in Argentina, Colombia, and Peru. Virus infection leads to significant reduction in the accumulation of total sugars in cassava storage roots. While CsTLV has become an important constraint to cassava production, little is known about how the virus evades the host defense. A better understanding of the virus biology and molecular biology would lead to improved diagnostics which are critical in producing virus-free, clean planting material.
Plant viruses encode RNA silencing suppressors (RSS) to counteract the RNA silencing-based plant defense system. However, no such RSS has been identified in torradoviruses. To further advance the characterization of CsTLV, we first used bioinformatics software to identify the candidate genes for functional characterization of virally coded RNA silencing suppression. Viral coat protein genes were cloned and each gene was separately expressed using agroinfiltration in transgenic Nicotiana benthamiana line 16c plants, using the green fluorescent protein as the visual reporter/marker.
Results indicated that none of the three different coat protein genes from CsTLV showed RSS activity. Future studies will include testing for RSS activity of the three coat protein genes in different combinations.

Towards Durable Wood-Strand Composite Mass Timber Panels

Towards Durable Wood-Strand Composite Mass Timber Panels

Primary author: Ruben Jerves
Faculty sponsor: Vikram Yadam

Primary college/unit: Voiland College of Engineering and Architecture
Campus: Pullman

Abstract:

Mass timber construction is rapidly growing in North America. This fast growth is imminent due to some features of this material. Wood has a high strength to weight ratio and lower environmental impact in contrast with other construction materials. Still, durability is a significant concern that needs to be addressed for the advancement of mass timber construction. Extreme care is required to protect members from exposure to high moisture environments while ensuring long-term durability. This project thus researches improvements of wood’s longevity by approaching two main issues associated with this: dimensional stability and decay resistance of wood due to moisture and biological organisms. At the same time, a sustainable approach is considered while utilizing small-diameter logs, which allow the forest industry to be optimized. This improvement in durability is achieved with the fabrication of Cross Laminated Strand-Veneer-Lumber (CLSVL) out of thermally modified ponderosa pine wood strands. State-of-the-art concepts and technologies are implemented in the process and the testing of the material. Where, at a first stage of the project, the thermal treatment of the wood strands is optimized through studies on wood-water interaction, assessment of physical properties, and a series of mechanical benchmark tests. The presentation will focus on the initial results of the thermal treatment of strands and its influence on the mechanical performance, physical properties, and bonding behavior. Subsequent work will involve the manufacturing of strand-based veneer lumber and mass timber panels and a robust assessment of the product.

Fitness outcomes of competitive interactions of Azotobacter vinelandii depend on nitrogen fixation ability and frequency

Fitness outcomes of competitive interactions of Azotobacter vinelandii depend on nitrogen fixation ability and frequency

Primary author: Chandra Jack
Co-author(s): Maren Friesen

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Cooperation is a core feature of sociality. It is one of the key forces behind the transition to multicellularity, the expansion of ecological niches, and increased genetic biological diversity. Altruism can only survive if both parties gain a benefit through increased fitness. The presence of cheaters, individuals that benefit from the relationship but do not provide any in return, can ultimately lead to the collapse of a population because those individuals have higher fitness compared to cooperative members. Prior to industrialized agriculture, over 90% of the nitrogen used by terrestrial plants was due to biological fixation of nitrogen by soil microbes but that number has dropped dramatically with increased application of external nitrogen. We can apply our understanding of microbial sociality to nitrogen-fixing bacteria to determine the correlation between fixation efficiency and fitness. In this study, we compete lab-generated mutants of Azotobacter vinelandii, that vary in their ability to fix nitrogen, at different frequencies to determine the correlation between fixation efficiency, fitness, and population frequency. We expect our results to show frequency-dependent selection where strains that do not fix as much nitrogen (cheaters relative to their competitive partner) will have the highest fitness when they are rare. Our results will also be used to develop models that can predict the outcomes of competitions based on growth rates which we hope to extrapolate to natural isolates. If we can unlock the complexity of microbial interactions, we can boost biological nitrogen fixation and decrease the economic and ecological toll of chemical fertilization.

Adaptive livestock vaccine decision-making among agro-pastoralists: results from modelling cognition and decision dynamics in an agent-based model.

Adaptive livestock vaccine decision-making among agro-pastoralists: results from modelling cognition and decision dynamics in an agent-based model

Primary author: Richard Iles
Co-author(s): Matthew Sottile; Ofer Amram; Eric Lofgren; Craig McConnel

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Livestock disease transmission through animal interactions represents a form of dynamic environmental systems. The inclusion of human behaviour to vaccinate livestock in a dynamic natural and cognitive environment is instructive to understand adaptive human behaviour and design effective livestock disease policies, particularly in low-income settings. Moreover, enhancing the behavioral realism of decision making models in agent-based models (ABM) is required. The current study models livestock vaccination decision making among agro-pastoralists in central Kenya. Our ABM integrates four sub-models: i) the Random Field Ising Model (RFIM) for decision making amongst connected heads of households; ii) a traditional SIRV disease model for Rift Valley fever (RVf) and Contagious Bovine Pleuropneumonia (CBPP); iii) a model for herd birth/death dynamics, and iv) herd movement. A logit transformed RFIM used in this work to link human memory and cognition, with social network pressure and public information concerning disease risks. The research question of interest is: ‘how do memory and cognition parameters in a logit transformed RFIM affect livestock vaccine choice?’. Three rounds of cognition and household survey data from Kenya (2017-2018) is used to calibrate parameters in the RFIM. Results from the logit transformed RFIM show that increases in the memory parameter, at higher levels of cognition has a disproportionate effect on the choice of the annual booster CBPP vaccine, in contrast to RVf which requires a once-for-life vaccine.

Development of a Functional Maternity Hospital Gown Through User-Centered Design

Development of a Functional Maternity Hospital Gown Through User-Centered Design

Primary author: Chanmi Hwang
Co-author(s): Lindsay McCoy

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Maternity hospital gowns are usually made according to a one-size-fits-all standard with full back openings which are physically and emotionally uncomfortable, not functional, and revealing. The purpose of this research was to understand the design requirements of patients and practitioners in order to develop a functional and sustainable maternity hospital gown design. The researchers applied user-centered design (UCD) methods to develop a new design based on data from market research (23 birthing institutions and 25 leading retailers) and focus group interviews (15 postpartum women). The researchers created a two-piece stretchy gown with an adjustable waist and a washable nursing breast pad insert system which contributed to the gowns overall fit, mobility, closure access, modesty, and tactile comfort. Through wear trials (5 women) and an online survey (501 women and 42 practitioners), participants found the prototype to be successful in enhancing physical and psychological comfort throughout different stages of labor and postpartum, resulting in a novel maternity gowns concept that address many needs of both patients and practitioners. The resulting technical package includes the order of operations, bill of materials, marker layout, and cost analysis for the new design which can be tested for mass production. Future research may explore partnering with a manufacturing company such as Medline, the largest manufacturer and distributor of medical supplies, to conduct a patient satisfaction survey after implementing the new design.

Youth’s Proximity to Marijuana Retailers and Advertisements: Factors Associated with Washington State Adolescents’ Intentions to Use Marijuana

Youth’s Proximity to Marijuana Retailers and Advertisements: Factors Associated with Washington State Adolescents’ Intentions to Use Marijuana

Primary author: Stacey Hust
Co-author(s): Jessica Willoughby; Leticia Couto; Jiayu Li

Primary college/unit: Edward R. Murrow College of Communication
Campus: Pullman

Abstract:

The current study explored the influences of advertising exposure, numbers of marijuana retailers, distance to retailers, and constructs from the Integrative Model of Behavioral Prediction, including outcome beliefs, perceived norms, and efficacy, on youth’s intentions to use marijuana in a state in which the use of recreational marijuana is legal. A state-wide online cross-sectional survey of 350 adolescents ages 13-17, residing in Washington state, was conducted in June 2018. The results of the regression analysis suggest that exposure to marijuana advertising, positive and negative outcome beliefs, and perceived peer norms were associated with intention to use marijuana. Distances to retailers moderated the relationships between exposure to advertising and intentions as well as between positive outcome beliefs and intentions. States that have legalized recreational marijuana may want to consider the location of retailers in relation to neighborhoods and advertising regulations to reduce appeal to youth. Additionally, prevention efforts could aim to influence outcome beliefs and norms in an attempt to reduce adolescents’ intentions to use recreational marijuana.

Effect of Total Sleep Deprivation on Word Recognition of Previously Studied Words with Different Emotional Valence

Effect of Total Sleep Deprivation on Word Recognition of Previously Studied Words with Different Emotional Valence

Primary author: Amanda Hudson
Co-author(s): Paul Whitney; John Hinson; Devon Hansen; Hans Van Dongen; Kimberly Honn
Faculty sponsor: Kimberly Honn

Primary college/unit: Arts and Sciences
Campus: Spokane

Abstract:

Stimuli with an emotional valence tend to produce better recognition from memory than neutral stimuli. Sleep loss is believed to increase reactivity to negative stimuli, compared to positive stimuli, which may comparatively enhance subsequent recognition from memory for negative stimuli. We investigated the impact of total sleep deprivation (TSD) on recognition accuracy for words with different emotional valence using the Affective Item Source Memory Task (AISM).

Fourteen adults (ages 21-39; 7 females) completed a 4-day/3-night laboratory study with a baseline sleep opportunity, 39h acute TSD, and recovery sleep. The AISM was administered at 16:30 during baseline and after 34h TSD. During a study phase, participants heard a list, twice, of positive, negative, and neutral words spoken with a male or female voice. During an immediately subsequent recognition phase, participants heard and judged whether words were previously presented (item memory). For words judged to have been presented previously, participants indicated whether those were presented by a female or male speaker (source memory).

We found session (p<0.001) and valence (p<0.001) effects on item memory, but no interaction. At baseline, accuracy was higher for neutral and positive words than negative words. During TSD, accuracy declined for all valences as expected. However, there was no comparatively greater impact on item or source memory for negative words nor any differential effect of TSD for different valences. Whether our results would hold with longer time intervals between task phases or an intervening sleep period remains to be determined. This research was supported by Jazz Pharmaceuticals.

Parental Engagement in Children’s English Language Learning: A Case Study of Transnational Chinese Families in the United States

Parental Engagement in Children’s English Language Learning: A Case Study of Transnational Chinese Families in the United States

Primary author: Yue Huang
Co-author(s): Anne Marie Guerrettaz; Sarah Newcomer
Faculty sponsor: Anne Marie Guerrettaz; Sarah Newcomer

Primary college/unit: College of Education
Campus: Pullman

Abstract:

Transnational migration redefines the lives of millions of Chinese migrant families in the United States, including parental engagement in child language education. This case study examines ways how parents from two Chinese transnational families participate in their children’s English language learning at home while living in the United States, using observations, interviews, and discourse analysis. Grounded on the traditional Chinese parenting concept of guan (Chao, 1994) and the Third Space theory (Bhabha, 1996), this study proposes “transnational guan” as a hybrid form of parental engagement, impacted by the families’ transnational experiences. Findings revealed by this study include: (a) a unique, multimodal “storybook” genre and related parent-child shared reading activity, (b) new parental roles during children’s English language learning, including amateur tutor and bridge, and (c) interactions that elucidate nuanced dynamics of parent-child relationships. Regarding the theoretical contribution, this study presents that homes of the transnational families are a Third Space, and the transnational guan is the parents’ reactions to such Third Space. Concerning practical implications, this study uncovers unique academic goals of educated transnational families. It also breaks with dominant discourses and stereotypes of academically high-performing Chinese students in the United States by revealing more complete picture of their complex educational situations.

Letting Go and Staying Connected: A theoretically guided, developmentally targeted, and empirically supported intervention for parents of students transitioning to college

Letting Go and Staying Connected: A theoretically guided, developmentally targeted, and empirically supported intervention for parents of students transitioning to college

Primary author: Laura Hill
Co-author(s): Brittany Cooper; Matt Bumpus; Kevin Haggerty; Richard Catalano; Martie Skinner

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Early adulthood is a critical developmental period when many youth transition from living at home with parents to the relative autonomy of college. This transition results in increased opportunity both for positive growth and identity development as well as increased risky substance use and sexual behaviors. This developmental transition also presents opportunities for prevention. Research shows that parents continue to influence young adult behavior even at a distance; however, few studies have tested parent-college student interventions. We created a parent-student handbook intervention that provides parents with tools designed to help them support their students as they transition to living away from home, by providing encouragement, communicating clear expectations, and supporting growth in students’ autonomy.

Data for the present study come from the efficacy trial of the self-directed handbook for parents of first-year college students. In the summer before college, parent-student dyads were randomly assigned to one of three conditions: control (N=313), parent handbook (N=278), or parent handbook plus booster texts (N=323). We collected data on substance use early in the students’ first fall semester at WSU.

Among students who reported substance use in high school, students in the handbook condition reported significantly lower increases in frequency of 30-day alcohol use, binge drinking, marijuana, and co-use once they came to college. Students who had reported no previous use were significantly less likely to report initiation of alcohol, marijuana, or co-use of both once they came to college. Results suggest that this low-cost intervention significantly reduces new students’ risk behaviors.

Multi-spectral Imaging in Winter Wheat Variety Improvement

Multi-spectral Imaging in Winter Wheat Variety Improvement

Primary author: Andrew Herr
Faculty sponsor: Arron Carter

Primary college/unit: Agricultural, Human and Natural Resource Sciences
Campus: Pullman

Abstract:

Multispectral imaging with unmanned aerial vehicles is a promising high-throughput phenotyping technology that has shown to help understand the causal mechanisms associated with crop productivity. This imaging technology can accurately predict complex agronomic traits like grain yield within a given generation, creating the potential to fast-track selections in plant breeding and increase genetic gains. Unfortunately, multispectral imaging has not been evaluated at selecting performance across years, limiting our understanding of predicting across environmental variation. The objective of this study is to determine the effectiveness and efficiency of prediction across years and locations within a breeding program. Spectral reflectance indices such as NDVI and NWI will be used to evaluate Washington State University winter wheat breeding lines between 2017 and 2020. Data will be collected using a DJI Phantom drone, equipped with a MicaSense camera, and data collected at heading date. Lines are observed from single location, single replication preliminary yield trials to multi-location, replicated advanced yield trials. Lines advanced in the breeding program will be evaluated across 20 different location-year trials. The indices collected from these trials will be used in indirect selection to estimate how well they predict performance of breeding lines across multiple location-years. Additionally, indices will be used as fixed effects in mixed models and genomic prediction modeling to further estimate their usefulness in genomie selection. The proposed research will be vital for plant breeder’s to understand the usefulness of multispectral imaging to improve winter wheat varieties while using fewer resources.