Poster Sessions

The emergence and spread of antibiotic resistance (AR) are one of the greatest global public health issues of the 21st century. AR challenges therapeutic potential against pathogens of humans and animals. Antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are the indicators of AR status in environmental settings. The environment has been implicated in the widespread of AR in clinical settings. ARB and ARGs have been observed in rivers, wastewater treatment plants (WWTPs) effluent and drinking water distribution systems. WWTPs are identified as reservoirs and sources for the release of ARB and ARGs into water sources. Conventional chlorination and ultraviolet (UV) irradiation considerably inactivate ARB but ARGs are not effectively degraded. For successful mitigation of AR proliferation, the inactivation of ARB without the degradation of AR determinants (e.g., gene cassettes, plasmids, integrons, or transposons) is not enough. Intact AR determinants within cell debris in the environment can confer resistance to bacterial populations downstream via horizontal gene transfer (HGT). Advanced oxidation processes (AOPs) that utilize the strong oxidizing power of hydroxyl radical ({HO}^.) and sulphate radical (S{O_4}^{.-}) are promising technologies for ARGs degradation. This lab-scale study determined the fundamental kinetic parameters of ARGs degradation during {HO}^. and S{O_4}^{.-} water treatments. S{O_4}^{.-} and {HO}^. were generated in a collimated low-pressure lamp UV apparatus with an average irradiance of 1.3 mW/cm2 using H2O2 and S2O82-. The degradation kinetics of intracellular and extracellular plasmid-encoded ARGs was examined. The degradation of tetA, ampR and sul1 ARGs were quantified using qPCR following exposure to UV, UV/H2O2 and UV/ S2O82-. Results indicate that extracellular ARGs degradation is at least 2-fold higher than intracellular ARGs degradation. Also, the nucleotides compositions of the target ARG amplicons influence the observed ARG degradation kinetics with higher degradation recorded for higher AT composition in qPCR amplicon. S{O_4}^{.-} resulted in higher ARGs degradation than {HO}^. and conventional UV at pH 7.4. Further analysis compared {HO}^. and S{O_4}^{.-} efficiencies for ARGs degradation under various water physicochemical parameters and elucidates the influence of pH on ARG degradation kinetics. Results here in show that {HO}^. and SO_4^{.-}AOPs can potentially serve as a barrier against AR dissemination in water environments. SO_4^{.-}AOP resulted in higher ARGs degradation than {HO}^. AOP. {HO}^. and SO_4^{.-}AOPs outperform conventional UV treatment in ARG degradation. This study provides useful information for reactor designs and setting operating conditions for the effective ARGs degradation during {HO}^. and S{O_4}^{.-} water treatments.

Recently, there has been a growing interest in color-changing materials for use in smart windows, displays, wearable devices, biosensors, chemical sensors, and energy storage. This includes materials that change color with exposure to electricity (electrochromism) or light (photochromism) and change in fluorescence intensity with the application of a voltage (electrofluorochromism). Although many materials and devices show one or two of these properties, there have been few that possess all three for truly multifunctional applications, for example, windows that can automatically darken with light exposure, or controlled with a low applied voltage during the day, while also controllably fluorescent at night. This is ideal to reduce solar heat gain and maintain occupant comfort in buildings while also useful for displays or lighting in the very same window device. Here, we aim to make such a device out of inexpensive and easily made materials. Dipyridinium thiazolothiazole (TTz) molecules have previously been used in organic solvents, which showed high color change contrast electrochromism and electrofluorochromism, however, these devices were not very reversible, used toxic solvents, and only showed one color change. TTz’s are rigid, highly conjugated, organic molecules synthesized via two-step reactions from inexpensive starting materials and are environmentally stable, while also able to reversibly gain two electrons, which cause color and fluorescence change. To reduce toxicity and possible leaks, we use water-based hydrogels that are inexpensive. In the hydrogels, the TTz’s show two color changes, a high fluorescence contrast, and photochromism, which can all be seen with the human eye, however, we use UV-vis and fluorescence spectroscopies to determine reversibility, stability, and exact color contrasts. A computer controlled potentiostat is employed to apply specific voltages to the hydrogel devices, which causes the color and fluorescence changes. By applying different voltages and monitoring color change, we determined the voltage needed to change the yellow device to purple or blue. Using those voltages, reversibility and durability studies were performed by cycling the device on/off while monitoring the color change using a UV-vis spectrometer or fluorometer. After 250 on/off cycles, the TTz hydrogel devices only lose 6% color contrast, which shows high contrast, high reversibility and stability. The devices also show strong electrofluorochromism, where fluorescence can be reversibly turned off with over 90% contrast. Although we have developed highly reversible, stable, large contrast, easily synthesized chromogenic dyes that are electrochromic, photochromic, and electrofluorochromic in simple, low-cost, aqueous hydrogel devices, we continue to make more reversible devices that can retain their colors after thousands of cycles and prolonged use. We have already fully characterized these devices for color changing, however, they also may have potential for applications like sensors, biosensors, energy production/storage, and wearable devices.

Background: Osteomyelitis is a serious bacterial infection of bone that is associated with progressive inflammatory tissue damage. Staphylococcus aureus is the principal causative agent of osteomyelitis and can enter bone following injury or surgery resulting in disease where treatment is often refractory. The increasing incidence of infections associated with antibiotic resistant strains of S. aureus has made defining the pathogenesis of staphylococcal osteomyelitis urgent. Resident bone cells, including bone-forming osteoblasts, are important for initiating and maintaining the progressive inflammation associated with osteomyelitis. Bacterially-challenged osteoblasts have been demonstrated to release inflammatory mediators that promote osteoclastogenesis and further drive inflammation through the recruitment of leukocytes such as neutrophils. Neutrophils are typically the first leukocytes recruited to sites of infection and possess various antimicrobial abilities including, phagocytosis, production of reactive oxygen and nitrogen species (ROS and RNS), neutrophil extracellular trap release, and synthesis of antimicrobial proteins. However, activated neutrophil accumulation can exacerbate the inflammatory bone loss associated with osteomyelitis by recruiting other leukocytes and by promoting osteoclastogenesis. Furthermore, neutrophils can inadvertently mediate host tissue destruction via excessive ROS and RNS production following bacterial phagocytosis, and may even serve as an intracellular reservoir for S. aureus. In the present study, we hypothesize that osteoblasts release chemokines that activate and recruit neutrophils, which may perpetuate host-mediated inflammatory damage in staphylococcal osteomyelitis. Methodology: In this study, we have assessed the expression of the neutrophil recruiting chemokines, CXCL1, CXCL2, CXCL3, CXCL5, CCL3, and CCL7, at the level of mRNA expression via RNAseq analysis and protein production via specific capture ELISAs in isolated primary murine osteoblasts following challenge with a clinical S. aureus isolate (strain UAMS-1) and in a mouse model of staphylococcal osteomyelitis that reproduces human disease. In addition, we utilized human promyeloblast leukemia-60 cell (HL-60s) line to assess osteoblast-mediated neutrophil migration via transwell migration assays and myeloperoxidase (MPO) levels were utilized as a marker for neutrophil activation. Results: We have found that protein levels of the neutrophil chemoattractants, CXCL3, CXCL5, and CCL7, are significantly elevated in infected bone tissue. Interestingly, isolated osteoblasts show marked increases in the mRNA encoding CXCL1, CXCL2, CXCL3, CXCL5, CCL3, and CCL7 following in vitro S. aureus challenge. Consistent with previous studies, we have shown dose-dependent production of CXCL2 and CCL3 by SA-infected osteoblast. Furthermore, we have shown the first demonstration of dose and time-dependent production CXCL3, CXCL5, CCL7, and CXCL1 by osteoblasts following in vitro S. aureus challenge. Importantly, we have determined that neutrophil-like cells express CCR1, a receptor for CCL3 and CCL7 necessary for neutrophil chemotaxis, and demonstrated osteoblast-mediated neutrophil activation and migration. Conclusions: The ability of S. aureus-infected osteoblasts to produce an array of chemokines that act via neutrophil chemokine receptors including CCR1 provides another potential mechanism by which bone cells can contribute to host responses following bacterial infection. However, it remains to be determined whether osteoblast-dependent neutrophil recruitment serves to limit bacterial burden or exacerbate the inflammatory damage associated with staphylococcal osteomyelitis.

Across the globe, numerous languages are in jeopardy and approximately 37% of the world’s languages are no longer sustainably passed from one generation to the next. Indigenous languages in the United States are also in jeopardy. The situation dire among the Eastern Band of the Cherokee Nation in western North Carolina, where less than two percent (250) of the 13,000-member Eastern Band are fluent Cherokee speakers. Efforts to revitalize Cherokee in both North Carolina and Oklahoma have included offering Cherokee language instruction at the university-level, in local community centers and churches, and in K-12 classrooms. These efforts, however, have been hampered by the lack of qualified teachers. Many Cherokee teachers are neither fluent in the language, nor trained in language teaching pedagogy. Exacerbating the challenge of finding qualified teachers is the lack of preparation programs. Only Northeastern State University (2020) in Oklahoma offers a bachelor's degree in Cherokee Education and the University of North Carolina at Charlotte (2020) recently launched a graduate certificate program that leads to a K-12 license to teach Cherokee. While these efforts represent significant steps in revitalizing the language, little is known about these programs and the extent they prepare teachers to teach such a unique language. In response, we are conducting a year-long case study, involving multiple data sources, to chronicle the experiences of a Cherokee teacher in North Carolina as he completes his teacher licensure program in a graduate program aimed at supporting Cherokee language renewal via the preparation of qualified teachers. This approach will help us understand the extent to which a graduate program designed to prepare teachers of a variety of different modern and widely spoken languages (e.g., Spanish, Chinese, French) is able to prepare someone to teach an endangered language spoken by very few people. The first interview occurred in Spring 2021, while the participant was completing coursework, in an effort to better understand the extent the program meets the needs of this Cherokee teacher. The second, (Fall 2021) coincided with his student teaching internship and explored the extent program coursework prepared him for this culminating student teaching experience and the high-stakes licensure assessments that come with it. The final interview will take place after completion of the licensure program and while the participant is serving as a licensed Cherokee teacher to investigate the extent the program prepared him. We are especially interested in the candidate’s view on how the program prepared him pedagogically, and how it could better support future Cherokee teachers. The interviews will be complemented by other data, such as three classroom teaching observations and candidate assessments. Specifically, we will analyze the Cherokee teacher’s performance on a performance-based assessment that is spreading across the country and required of all new teachers in North Carolina (edTPA) as well as his performance on a valid, reliable, and widely used classroom observation instrument (C-PAST).

Frost action (heaving and thawing) is a perennial problem encountered in the design, construction, and management of civil engineering structures, particularly road pavements in cold regions and areas that experience seasonal sub-freezing temperatures. Nationally, this leads to recurrent annual maintenance costs estimated at over 2 billion dollars, as well as additional economic impacts because of related vehicle damage, road closures, and weight restrictions. Studies identify three basic requirements for frost action; freezing temperatures, availability of water, and frost-susceptible soils. While advances have been made in the design for freezing temperatures and providing for groundwater separation, very little progress has been made in terms of in-situ soil improvement. A cost and labor-intensive approach is to undercut and replace unsuitable frost-susceptible soils. As an alternative, this presentation will describe Engineered Water Repellency (EWR), a process in which soils are made hydrophobic. This is achieved by combining soils with cost-effective and environmentally compatible polymers and other complex organic molecules. This study proposes an innovative approach for mitigating frost action through engineered water repellency. A frost-susceptible soil was collected from a test plot at the Charlotte Douglas International Airport and treated with a commercially available organosilane. Using the standard proctor test method, changes in density and corresponding water content were obtained. Data on water content, soil temperature, suction, and electrical conductivity were collected every ten minutes using Teros 12 and 21 sensors in both untreated and treated soil samples to monitor water infiltration. Preliminary results indicate an increase in the maximum dry density from 17.54kN/m3 to 17.66kN/m3 and a decrease in the optimum moisture content from 17.36% to 11.75% after treatment. Data obtained from performance tests carried out under sub-freezing weather conditions indicated that the treatment was effective in limiting the infiltration and migration of water into the soil matrix when compared with the untreated soil. As such, engineered water repellency may be a viable solution for Airports and Departments of Transportation seeking methods to mitigate frost action.

When proteins are made in the cell, their forms are reminiscent of an unwound ball of string. To become active, they must be wound up into specific shapes (“active conformation”). This winding and folding function is performed by “chaperone” proteins such as Hsp70. These proteins are present in all organisms from bacteria to yeast, frogs, mice and humans. Proteins can become unfolded throughout their lifespan at which point Hsp70 can rebind and refold them. Cells must be able to respond rapidly to changes in their surrounding temperature (heat shock). The response to heat is mediated by molecular chaperones such as Hsp70 that refold denatured proteins. Hsp70 function can be altered through the addition and removal of phosphate groups (known as phosphorylation). These modifications are added after protein is synthesized (translation) thus called as post-translational modifications. We liken Hsp70 to a piano with each phosphorylation being a key on that piano. By pressing the keys in combination (adding a specific pattern of phosphorylation) produces a particular song (a unique function on Hsp70). There are a total of 85 phosphorylation sites on Hsp70 currently reported that can be phosphorylated. The role of post-translational modifications (PTMs) on Hsp70 under heat shock are poorly understood. To understand how heat shock impacts Hsp70 PTMs, we performed quantitative mass spectrometry on yeast Hsp70 isolated from untreated and heat shocked cells. Interestingly, the only PTM site up-regulated on Hsp70 was phosphorylation at threonine T492 (T492), a result that was confirmed via Western Blotting with a phospho-specific T492 antibody. T492 phosphorylation was activated rapidly (<5mins) by heat and by other cell-wall damaging agents and was dependent on proteins in the cell-wall integrity pathway. Mutation of T492 to alanine (phospho-mutant) resulted in yeast unable to survive exposure to heat stress or cell wall damaging agents. T492A yeast were not impacted for survival to genotoxic stresses, suggesting a fine-tuning rather than abolishing of chaperone function. The T492 phospho-mutant was unable to activate the heat shock response (HSR) confirming the importance of T492 phosphorylation for survival at high temperature. Taken together we believe that T492 phosphorylation of Hsp70 is an initiating event in the heat shock response, a process which may be universally conserved in all organisms.

As populations grow and vehicle density increases, traffic accidents become more common. Bicycle lanes have been proven to reduce these accidents, improving safety for vulnerable road users such as bicyclists and motorcyclists. However, bicycle lanes are expensive to implement and increase road congestion as they’re built. Therefore, city officials need to decide which roads need the most upgrades. To evaluate which roads would benefit cyclists more with the construction of a bicycle lane, we propose a system that collects traffic data to detect which routes are used more and create the most congestion. Our goal is to collect audio, magnetic, and location data from cyclists’ smartphones, which are then analyzed to determine which roads get more congested when cyclists are riding. Audio and magnetic sensors consume low energy and are unaffected by weather and visual disruption. Having this data collected via smartphones means we can collect data from multiple roads from local cyclists without the need to install multiple devices and disrupt traffic. We evaluated various machine learning (ML) models, such as CNN and LSTM, to assess which is most effective at detecting a vehicle passing by the recording device. Models were trained on (1) publicly available traffic datasets and (2) our own recorded roadside data, showing that vehicles can be detected with an estimated accuracy of around ~84%. Published work by other researchers and our own collected data show the potential for magnetic sensor data to determine if a vehicle detected in the audio data is in the same lane as the cyclist, increasing the result's reliability. With the proposed system, local cyclists can help provide essential traffic data to aid government decision-making. This information can be used to help determine which roads are more dangerous and may need a bicycle lane most. Not only is the data collected without road interruptions, but they are collected from users who travel these roads regularly and would be benefited directly from road upgrades.

Redox flow batteries (RFBs) are promising energy storage devices that play a pivotal role in mitigating the gap between grid scale energy demand and utilization. Conventional RFBs rely on acidic electrolytes (H2SO4) and expensive vanadium-based salts. Aqueous organic RFBs that operate at neutral pH are particularly attractive from a safety and cost standpoint. However, very few organic compounds function as efficient redox couples at pH 7. Our group has been studying substituted [3]radialene molecules as catholytes for aqueous organic RFBs. Here, we describe the synthesis and characterization of a series of cyanoacetamide-functionalized [3]radialenes. Specifically, mono-cyanoacetamide-tetracyano[3]radialene supports multielectron transfer in acetonitrile and reversible electrochemistry at neutral pH. We also prepared a highly soluble sulfonoacetamide-functionalized [3]radialene from inexpensive precursors that exhibits higher voltage oxidation in solutions of NaCl. Electrochemical analysis, also presented in this report.