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Showcase Marilyn Reed

Monolignol biosynthesis pathway

Monolignol biosynthesis pathway

Primary author: Parvaneh Ahmadvand
Faculty sponsor: ChulHee Kang

Primary college/unit: Arts and Sciences
Campus: Pullman

Abstract:

Biomass as a renewable carbon source for the generation of biofuels and biomaterials has become increasingly important in the quest for sustainable development. Plant secondary cell walls, which have a complex structure consisting of cellulose, hemicellulosic polysaccharides and lignin, constitute the majority of plant biomass. At the step of refinery, in the different chemical and physical processes, these various polymers are separated. Polysaccharides are hydrolyzed to fermentable sugars, whereas the lignin can be used as composites, nanoparticles and carbon fibers.There are there types of lignin: H (soft), G (semi-hard), S(hard).Of the several enzymes in the phenylpropanoid pathway, 4-coumaroyl-CoA ligase (4CL) is the central enzyme. Sorghum bicolor, the fifth most important cereal crop, is a plant that is a candidate for producing large volumes of biomass, in part because its tolerance for drought and a wide pH range. The brown midrib (BMR) is a genetic mutation that results in a forage with a reduced lignin content, increased protein content and higher palatability. The research is aimed at obtaining a better understanding of those Bmr2 and its mutations through their structural characteristics. Based on enzymatic assays, analysis of kinetics, a plausible mechanism for its broad substrate specificity will be proposed. Also, in the final step of lignification, Peroxidase and Laccase catalyze the oxidative radicalization, followed by combinatorial radical coupling. This will open a new perspective on understanding the catalytic process and innovative ways to increase the amount of H and G lignin and decrease the amount of S lignin so that cellulose can be more easily accessed for biofuel production.

A Social Network Analysis of Consumer Perceptions Receiving Tattoos and the Current General Meaning of Tattoos: A Study of Connecting Hashtags Used on Instagram

A Social Network Analysis of Consumer Perceptions Receiving Tattoos and the Current General Meaning of Tattoos: A Study of Connecting Hashtags Used on Instagram

Primary Author: April Alley
Co-Author(s): Tzu Yu Wang; Chih Han Wang
Faculty Sponsor: Jihyeong Son

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

Abstract:

Overall, throughout history, tattoos have evolved to be used in all different types of human membership or groups type settings (Park, 2016). It was previously understood, tattoos were used as a tool to signal to groups; where the individual has come from geographically and what group the individual belongs to. However, with the growth of social media, the meanings of tattoos have been changed and it is used for the ways to reveal individuality. Therefore, this study examined how tattoos are presented and communicate a person’s identity, values, and experiences on social media. 6237 useable online posts including hashtags related to tattoos on Instagram were collected using InstaCrawlR software and Social network analysis of hashtags were conducted using R and Gephi. Finally, 54 hashtags are shown in Gephi and are connected using the highest rate of words associated with #tattoo. . Hashtag themes were categorized based on 5 themes chosen to categorize the research: (1) tattoo (i.e., #tattooink, #tattooist), (2) lifestyle (i.e., #photooftheday, #fitness), (3) art (i.e., #artwork, #illustration), (4) self-identification (i.e., #artist, #tattooartist), and (5) emotion (i.e., #love, #happy). In social media, tattoos as a positive symbolic present lifestyle, art, and identification. Tattoo as a significant element to delivering self-information. For the emotional aspect, it connects with positive meanings such as happy, or love. In the past, tattoos were sometimes regarded and used for identifying criminal activities and associations. However, tattoos have become a positive and individualized symbol on Instagram.

Characterizing Compost Teas for Biofertilization Research

Characterizing Compost Teas for Biofertilization Research

Primary author: Adel Almesmari
Faculty sponsor: Lynne Carpenter-Boggs

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

Abstract:

Compost teas (CT) have gained attention as possible alternatives or supplements to synthetic fertilizers and pesticides used in agriculture. CTs are becoming increasingly popular, and several studies have shown that CTs can provide nutrients to plants, increase soil and foliar microbial diversity, stimulate crop systemic disease resistance, and build soil structure. However, CTs are poorly studied and controlled, and vary widely in composition. For both research and practical purposes, there is need to standardize recipes for CTs with repeatable microbial and chemical characteristics. This experiment was conducted to determine the effects of compost type, recipe (additives and aeration), and brewing time on characteristics of CTs. Eight CTs were prepared by using four recipes (A, B, C, and D) with two types of compost (WSU bedding compost [Wb] and vermicompost [Ver]) or control (no compost). Each solution was characterized after 1, 3, 6, and 10 days of brewing time. CT characteristics were highly affected by the recipes and time of brewing, and minimally affected by type of compost. Recipes A and B supported high microbial populations and more soluble nutrients compared to recipes C and D. This was true with both types of compost and the controls with no compost. Microbial populations were smallest at day 1 and greatest at day 3. The study shows that CT characteristics can be well managed by recipe and brewing time. This work has potential to affect all future work on CT by describing standardized recipes and procedures for CTs with particular desired characteristics.

The hijacking of barley wall associated kinases by a fungal pathogen, Bipolaris sorokiniana to cause spot blotch disease

The hijacking of barley wall associated kinases by a fungal pathogen, Bipolaris sorokiniana to cause spot blotch disease

Primary author: Gazala Ameen
Co-author(s): Shyam Solanki; Thomas Drader; Lauren Bittara-Sager
Brian Steffenson; Chrysafis Vogiatzis; Robert Brueggeman
Faculty sponsor: Robert S. Brueggeman

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

Abstract:
Plants have cell membrane bound immunity receptors that sense the pathogen attack and triggers the signalling to initiate defense responses which mostly result in localized programmed cell death (PCD). This PCD mediated resistance subdues biotrophic pathogens, which survive on living cells but can be hijacked by necrotrophic pathogens, that acquire nutrients from and colonize the resulting dead host cells to further plant diseases. We report that a necrotrophic pathogen Bipolaris sorokiniana, hijacks two barley wall associated kinase (WAK) cell-membrane bound receptors, Sbs1&2, underlying the previously reported rcs5 disease resistance locus on barley chromosome 7H to intentionally trigger the plant immune responses to cause PCD and ultimately causes spot blotch disease. Post-transcriptional gene silencing of Sbs1&2 genes in the susceptible barley lines Steptoe and Harrington resulted in spot blotch resistance, thus, proving that these two WAKs function as susceptibility genes. The expression analysis of Sbs1&2 showed nearly undetectable expression in resistant and susceptible lines prior to pathogen challenge, however, upregulation of both genes specifically occurred in susceptible lines post inoculation. Allele analysis of Sbs1&2 from eight resistant and two susceptible barley lines identified sequence polymorphisms associated with disease phenotypes in the promoter regions indicating that differential transcriptional regulation by virulent isolates contribute to WAK mediated susceptibility. Virulent isolate apoplastic wash fluids induced Sbs1 suggesting regulation by an apoplastic-secreted effector. Thus, the Sbs1&2 genes underlying the rcs5 QTL are the first susceptibility/resistance genes identified that confer resistance against spot blotch, a disease that threatens barley and wheat production worldwide.

Waterjet Steerable Needles: A New Promise for Improving Medical Procedures

Waterjet Steerable Needles: A New Promise for Improving Medical Procedures

 

Primary author: Mahdieh Babaiasl
Co-author(s): Fan Yang; John Swensen
Faculty sponsor: John P. Swensen

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

Abstract:

Steerable needles are a type of medical devices that can steer around obstacles to reach to a target location within patient anatomy and thus can improve the accuracy of medical procedures. Radius of curvature is an important parameter while designing steerable needles and achieving smaller radius and being able to control it is of paramount importance in steerable needle technology. We have developed a new class of steerable needles namely fracture-directed waterjet steerable needles in which the direction of the tissue fracture is controlled by waterjet and then the flexible needle follows. Needle steering tests are performed on soft tissue simulants, and the Radius of curvature of the needle is controlled by duty cycling of waterjet whereas 100% percent duty (waterjet is ON in all steps) gives the best radius of curvature. Smaller radius of curvature makes steering around tight obstacles possible and improves the performance of steerable needles. It is shown that the radius of curvature is a linear function of duty cycling for a range of the tissue stiffnesses used. A discrete-step kinematic model is used to model the motion of the waterjet steerable needle. This model consists of two parts: (1) the mechanics-based model predicts the cut-depth of waterjet in soft tissue based on soft tissue properties, waterjet diameter, and water exit velocity, and (2) a discrete-step kinematic unicycle model of the steerable needle travel. The proposed method of needle steering promises steerability and radius of curvature unattainable by current steerable needle technologies.