September 17, 2021

About the speakers

All the participants are from the University of Nebraska-Lincoln's Summer Research Program in Summer 2021.

Jalen Garza is undergraduate senior graduating this Fall semester from the University of Texas Rio Grande Valley (UTRGV) with a bachelor's in civil engineering. Some research interests he has are in structural and transportation engineering. Some goals he has is to go to graduate school for his masters in Structural Engineering here at UTRGV hopefully next fall, and to take and pass the F.E exam ( fundamentals of Engineering Exam) to become a certified engineer.

Amairani Salazar is a current senior enrolled in the honors college and studying civil engineering here at the University of Texas Rio Grande Valley. She graduated from high school and South Texas College with her Associate’s Degree in 2018 and upon arriving at UTRGV, she became a member of the American Society of Civil Engineers (ASCE) and then Eta Omicron Nu, an Honors College affiliated organization. She plans to graduate with honors by December of 2021. After graduation, she would like to get started with her graduate studies and pursue her career through a company that will allow her to practice her studies and engage in her specialization. Some of her research interests include but are not limited to: soil behavior, shallow and deep foundations, reinforced soil structures, field instrumentation and testing, and geo-environmental engineering.

Jessica Ayala is a senior at UTRGV. She is majoring in biology and has a strong interest in insect-ecology.

Ms. Isabella Rodriguez is a senior majoring in Biology.

Undergraduate Summer Research Showcase featuring UTRGV students majoring in Civil Engineering & Biology

"Computer-Vision Based Health Monitoring of Aging Rural Bridge Infrastructure" presented by Mr. Jalen Garza, majoring in Civil Engineering

Abstract: Bridges are a critical source of infrastructure and cracks can cause a significant damage to the lifespan of a bridge due to the chemical penetration into the cracks. Regular inspections that can collect crack properties is vital to regularly maintaining the safety of the bridge. In this study, we created a computer vision-based system that can autonomously monitor aging bridge infrastructures using an Unmanned Aerial Vehicle (UAV). This system is composed of four major steps consisting of (1) Image Acquisition, (2) Crack Identification, (3) Crack Assessment, and (4) Creating a visualization Crack map. It would be able to take images and identify cracks by creating a segmented mask using Mask R-CNN. From the mask, crack properties can be calculated such as length, width, and orientation. Lastly creating a labeled orthomosaic map that has cracks highlighted along with its properties. The performance of the proposed method was tested using various crack images from a bridge in Omaha, NE and the results showed good performance of crack detection and its measurements. Crack inspection is very important in engineering because it is directly related to the safety, health, and the applicability of concrete structures. The system created can be used as inspection tool for engineers to provide multiple properties of cracks because its significantly more efficient and safer to deploy than conducting human based inspections.

"Analyzing Resistance of Sorghum plants to Sequential Aphid Attacks" presented by Ms. Jessica Ayala, majoring in Biology

Abstract: Sorghum is a widely used cereal crop that is severely impacted by aphid infestation. Sorghum is subject to predation from multiple insects at a time so the objective of this research is to determine the effects of sequential aphid attacks on sorghum plants. In order to achieve this, Sorghum plants were infested with either 10 sugarcane aphids or 10 greenbugs were placed on a sorghum plant and then removed after 48 hours and infested with the alternate species of aphid. Gene expression studies were also conducted which compared the housekeeping primer, Tubulin, to the pathogenesis related genes PR1 and PR10. The results of the bioassay indicate that Greenbug infested Sorghum plants are more resistant to Sugarcane aphids. The results from the gene expression study indicate that Greenbugs induce a stronger defense response in Sorghum plants than Sugarcane aphids. The information yielded from this study can contribute to sustainable pest management strategies by reducing chemical applications on crops and aiding in the designing of aphid resistant crops.

"Evaluation of a Slope Stability in Nebraska with Biopolymer Treated Soil" presented by Ms. Amairani Salazar, majoring in Civil Engineering

Abstract: Slope stability is a significant portion to the design of safe human-made or naturally occurring slopes, and a critical aspect to civil engineering. More often than not, landslides or failure of slopes occur due to gravitational force, water seepage, or surface erosion which develops an inconvenience to infrastructure that is settled upon suspected soil. Bio-polymeric reinforced soil is one adopted practice that has shown promise in soil quality enhancement. In the present study, xanthan gum, a polysaccharide biopolymer formed from Xanthomonas campestris typically used in the food industry is utilized for its effect on soil strength which was evaluated by the Nebraska Department of Transportation in a study called the Nebraska Specific Slope Design Manual (M061). The purpose of this paper is to determine whether xanthan gum can prove its effectiveness on the field as was shown in the lab through numerical modeling and slope simulations. The geotechnical software GeoStudio was executed to understand seepage and slope stability. In addition, two models based on Verdigre Slope, located in Knox County, Nebraska where slope failures have occurred were evaluated. One model was analyzed with untreated soil while the other had a section that contained biopolymer-treated soil. The comparison between the two was done based on the groundwater flow due to severe weathering and the factor of safety attained from the slope analysis. Based on the models developed it was found that severe precipitation and drainage had insignificant effect on the pore-water pressure and the factor of safety however the factor of safety was able to increase at least 5% indicating that Xanthan Gum was effective in soil treatment.

"Factors that Effect the Brown Midrib 2 Gene on Sugarcane Aphid Reproduction" presented by Ms. Isabella Rodriguez, majoring in Biology

Abstract: The sugarcane aphid (Melanaphis sacchari) is one of the most important insect pests of sorghum (Sorghum bicolor) and grain in the United States. Aphids insert their stylets into the plant tissues and feed on phloem sap. Aphids secrete honey dew on the plants which further promote the growth of sooty mold, overall affects the photosynthetic efficiency of plants. 4-coumarate-CoA ligase (4CL) is an enzyme that catalyzes the chemical reactions responsible for the synthesis of various phenolic compounds and flavonoids. Our research goal was to determine the effects of the Brown midrib 2 gene (bmr2, 4CL) on sugarcane aphid reproduction. We know because of the phenylpropanoic pathway that if the 4CL gene is absent, it will reduce flavonoids, lignin and soluble metabolites, which is important in providing resistance to pathogens in plants. The data we collected is important and served as a base-line study for further exploring the role of key genes, signaling networks, and defense pathways that contribute to sorghum resistance to sugarcane aphids. Our ultimate goal is to help develop new targets for pest control, and to reduce our dependence on toxic and harmful insecticides.