5^th Annual College of STEM Science Symposium

Description: This publication is the collection of all abstracts of works presented at the 5^th Annual College of STEM symposium.

Abstract. The update includes the information on the calibration, design, construction and deployment of core modules of DUCK (Detector system of Unusual Cosmic-ray casKades), a cosmic-rays detector system aimed to study the Extensive Air Shower disk thickness as compared to CORSIKA simulations, to join the efforts in the search for the Cosmic Ray Ensembles and to further study the latest advances in the cosmic-rays field, like studying the multi-modal cosmic ray events. The project involves computer simulation activities, design and construction, data acquisition system design, data collection and analysis, allowing participation of students pursuing not only physics but also other STEM fields, such as Chemistry, Engineering and Computer Science.

Abstract. Freshwater environments are recognized reservoirs of environmentally acquired antimicrobial resistance (AMR), presenting risks to public and ecosystem health. In this study, bacterial isolates were collected from Reynolds Nature Preserve, a local freshwater site in Clayton County, Georgia, and characterized using standard microbiological methods including Gram staining, biochemical assays, and Kirby-Bauer disk diffusion susceptibility testing. All three isolates (C1, C2, and D2) were identified as Gram-negative, non-motile, citrate-positive rods consistent with environmental enteric bacteria, with preliminary profiles suggestive of Klebsiella spp. and Escherichia spp. Antibiotic susceptibility testing indicated broad susceptibility across most clinical antibiotics, with the exception of intrinsic erythromycin resistance. Water chemistry analysis revealed soft, slightly acidic freshwater (pH 6.3) with low ionic strength and total dissolved solids, and the presence of total coliforms but no detectable E. coli or fecal coliforms. Future work will include 16S rRNA gene sequencing for definitive species identification and molecular screening for AMR gene determinants. These findings contribute to an emerging understanding of environmental AMR at the community level and underscore the value of integrating undergraduate researchers in active public-health-relevant science.

Abstract. Freshwater quality in the United States is taken for granted compared to many regions worldwide. This study evaluated key water quality parameters in a freshwater stream at Reynolds Nature Preserve in Morrow, Georgia. Using a commercial testing kit, researchers analyzed 17 water quality parameters from four sources (n = 6 replicates/source): stream water from two locations along the stream, distilled water (control), and tap water. Significant differences were detected among treatments in total dissolved solids (P < 0.05). These findings highlight a measurable variation in basic water chemistry across common freshwater sources. Future work will incorporate larger sample sizes to improve analytical robustness and will examine how these chemical parameters correlate with microbiological data collected from the same site.

Abstract. Clean drinking water is a fundamental human right, yet access remains a global public health challenge due not only to unequal distribution but also to the quality of available water sources. Natural freshwater environments can harbor bacteria with pathogenic potential and intrinsic antimicrobial resistance, posing risks to both human and ecological health. In this study, bacterial isolates collected from a freshwater site at Reynolds Nature Preserve were characterized using classical microbiological techniques, including aseptic sampling, streak plating, Gram staining, and biochemical testing. Antibiotic susceptibility was evaluated using the Kirby–Bauer disk diffusion method, and results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Several Gram-negative environmental isolates were identified, exhibiting diverse antimicrobial resistance profiles. These findings suggest that natural freshwater environments may serve as reservoirs of antimicrobial resistance, underscoring the importance of continued environmental surveillance.