Office of Undergraduate Research

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Emphasizing equitable and inclusive access to research opportunities, the University of Maryland's Office of Undergraduate Research (OUR) empowers undergraduates and faculty to engage and succeed in inquiry, creative activity, and scholarship. This collection includes materials shared by undergraduate researchers during OUR events. It also encompasses materials from Undergraduate Research Day 2020, Undergraduate Research Day 2021, and Undergraduate Research Day 2022, which were organized by the Maryland Center for Undergraduate Research.

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Now showing 1 - 7 of 7
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    Recognition of Aminated Guests by Acyclic Cucurbiturils in Biological Conditions
    (2020) Shah, Rohan; Isaacs, Lyle; Zebaze, Sandra
    The acyclic cucurbituril Motor2 has already been well documented in its binding to several types of molecular guests in phosphate buffer. However, while these tests provide a rough idea of motor2 affinity to different types of guests, they are incomplete in that they do not reflect how motor2 actually binds in body conditions. The human body contains many proteins and macromolecules that can affect the host-guest interactions of motor2, so it is important for new binding constants to be measured for motor2 in body conditions. In order to do this, Isothermal Titration Calorimetry (ITC) was used to measure motor2 binding constants to several different guest types in several different solutions, including albumin and fetal bovine serum. It was found that when tested with cyclic, monoaminated guests, motor2 binding affinity did not decrease significantly from phosphate to protein serum solvents. This retained affinity held across several different ring sizes and shapes. Motor2 binding affinity did suffer greatly in protein serum for guests that were linear, regardless of how many amines they had. The results also indicated that more hydrophobic guests do not bind as well to motor2 once albumin and other proteins ae introduced to solution, while hydrophilic, polar guests have better affinity retention. The ITC testing results indicated that motor2 binding in body conditions is heavily dependent on the shape of the guests it is binding to, and that motor2 would be most effective at its purpose in the human body if it was used to target cyclic amines and similar types.
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    COMPARISON OF RIBOSWITCH REPORTER SYSTEMS FOR LIVE CELL IMAGING OF CYCLIC-DI-GMP DYNAMICS IN BACILLUS SUBTILIS POPULATIONS
    (2019) Pierre, Yasmine; Spirito, Catherine
    Fluorescent riboswitch reporters can be used in vivo to monitor metabolite dynamics. Previous work used a fluorescent yfp reporter based on a cyclic di-GMP responsive riboswitch from Bacillus licheniformis to monitor cyclic di-GMP levels in individual Bacillus subtilis cells. The previous study found that cell fates in Bacillus subtilis are not uniform in the presence of varying cyclic di-GMP levels. It is important to further develop tools that enable single-cell imaging in Gram-positive bacteria. Fluorogenic aptamers are single-stranded RNA molecules that have been evolved via in vitro selection to bind strongly and specifically to fluorophore molecules and emit a fluorescent signal. These fluorogenic aptamers can be used instead of fluorescent proteins in riboswitch reporter systems to provide a more dynamic read-out of metabolite dynamics in cells. However, relatively little work has been done to evaluate the use of these fluorogenic aptamers as reporter systems in Gram-positive bacteria. The objective of this project is to evaluate the use of four different fluorogenic aptamers (Mango-III, Broccoli, dimeric Broccoli, and SpinachII) instead of yfp in a cyclic di-GMP responsive riboswitch reporter system in Bacillus subtilis. All plasmids containing the riboswitch reporters were constructed and successfully transformed into E. coli cells. Subsequently, the cyclic di-GMP responsive riboswitch reporter systems were successfully transformed into B. subtilis WT PY79 and a 𝝙pdeH mutant. Future work involves evaluating their performance in vivo in B. subtilis via laser confocal and fluorescence microscopy.
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    Investigating Magainin through Computational Molecular Modeling
    (2020) Holoman, Tyla; Klauda, Jeffery
    Magainin is a 23-residue, helical, antimicrobial peptide found in the skin of the Xenopus laevis, also known as the African Clawed Frog. Magainin is important because it can disrupt electrochemical gradients in the cell membranes of many bacteria, tumors, and fungi, which is extremely useful in pharmaceuticals for killing these organisms. Understanding how Magainin interacts with cell membranes is an important part of understanding how it could work medicinally, and one of the best ways to understand these reactions is through computational protein modeling. Ten membrane protein systems containing Magainin and a membrane bilayer were constructed to analyze Magainin’s behavior and interactions with a model for the outer skin membrane. These systems were simulated by a supercomputer for about 300 ns each to allow the peptide to fully interact with the membrane bilayer. Now that the simulations have been completed, they are being analyzed to determine exactly what patterns of behavior were exhibited by Magainin when placed near a model skin membrane.
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    Encapsulation of Candida albicans in Alginate Polymer
    (2020) Okunrinboye, Funke; Karlsson, Amy
    Candida albicans is a commensal opportunistic fungal pathogen. It is a polymorphic organism that exists in pseudo-hyphal, hyphal and yeast forms in human hosts. C. albicans causes superficial and systemic infections, including oral thrush, vaginal yeast infections, and systemic bloodstream infections. Systemic candidiasis can be deadly in immunocompromised patients such as transplant recipients and patients that have HIV, cancer, and diabetes mellitus. C. albicans infections are associated with high morbidity and mortality rates yearly. The characteristics of C. albicans associated with an ability to cause infections involve cell adhesion, dimorphism, phenotypic switching, thigmotropism, and biofilm formation. These characteristics aid in yeast dispersal, virulence and resistance to current antifungal therapies. Due to the toxicity of antifungal therapies to human host cells, the resistance of C. albicans to antifungal therapies, and Candida’s ability to escape the white blood cells, newer approaches to better study C. albicans are needed. Encapsulation of yeast cells will allow observation of cell signaling, growth patterns, and, ultimately, enable the development of better alternatives to prevent biofilm formation and C. albicans hyphal growth, thereby limiting virulence. Anionic alginate polymers were used to mimic human host cells for Candida encapsulation observation. and C. albicans strain SC5134 was embedded in the capsules. The cells grew predominantly in the yeast form at 35 °C but showed significant hyphal growth at 37 °C, in both liquid growth medium and in the alginate capsules. The results also show that C albicans can successfully be encapsulated and that growth can be observed in the capsules.
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    Bacteria-mucus interactions & their role in chronic lung infections
    (2020) Curry, Keyona; Joyer, Katherine; Duncan, Gregg
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    Development of 3D Printed Honeycombs for Crash Mitigation Applications
    (2020) Harvey, Rachel; Wereley, Norman; Mao, Min
    Honeycomb structures have been studied thoroughly to understand their in and out-of-plane mechanical properties. The ability of honeycombs to effectively absorb energy makes them ideal for usage in crash mitigation, particularly for helicopters and automobiles. Currently, when crushed by a dynamic load, there is an impulse in force prior to a steady absorption – which could be detrimental in such crash mitigation applications. In this study, 3D printed honeycombs are investigated for subsequent crush efficiency with quasi-static and dynamic crush tests. 3D printing, rather than conventional manufacturing, allows for structural modifications within the honeycomb that influence its force-displacement profile. Buckling initiators on the face and/or vertex of honeycombs should reduce the initial peak stress and increase the strain at which densification, the point at which the stress once again increases, begins. The experiment is not complete, but thus far, buckling initiators have proven to decrease the initial peak stress of tested honeycombs. Future directions for the project include testing honeycombs of other materials with buckling initiators, and the implementation of variations of current buckling initiator designs.
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    Influence of Compost Amendment on Shear Properties of Topsoils Used in Highway Slopes
    (2020) Stewartson, Erin; Aydilek, Ahmet
    Erosion of highway slopes is of the utmost importance because it can lead to a decreased quality of the soil underneath, reduced water quality, and exacerbated air quality. Current highway slopes are implemented using compacted inorganic topsoil or occasionally by placing a layer of compost above the existing topsoil layer. The single topsoil layer can be susceptible to erosion but, if blended with compost materials, may potentially yield vegetation that reinforces the strength of the soil. The potential implementation of compost-amended topsoil on highway slopes is a sustainable practice due to larger amounts of compost use in construction but requires additional research to evaluate the geotechnical properties of these systems. A research study was undertaken to evaluate the changes in shear strength of topsoil upon amending with two common composts. Four mixtures were prepared at varying percentages of composts and one topsoil. Direct shear tests were performed on pure topsoil, composts, and the blends. Shape properties of the materials were defined using digital image analysis. The results indicate that the drained friction angle increased from 360 to 440, and the angularity increased from 2608 to 3127 due to addition of the compost material. The shape parameters of Form 2D, flatness, sphericity, elongation, angularity, and texture were compared with the respective friction angles; angularity and Form 2D were found to have the greatest correlation displaying high R^2 values ranging from 0.816 to 0.940, regardless of compost type.