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This study investigates the influence of a place-based, hands-on engineering learning experience on rural middle school students' engineering career aspirations, using Social Cognitive Career Theory (SCCT) as a framework. Employing a mixed-methods approach, we explored how these localized learning experiences shape students' career goals through socio-cognitive factors such as self-efficacy, outcome expectations, goals, and interest. Quantitative analysis of pre- and post-activity surveys revealed significant increases in career aspiration scores, particularly among students from farming backgrounds and female students with initially lower expectations. Path analyses indicated that self-efficacy and interest were the strongest mediators between Place-based learning and engineering career aspirations. Qualitative data from student reflections corroborated these findings, highlighting key engagement factors such as real-time sensor feedback, hands-on interaction, and connections to lived experiences and familiar applications like farming. This experience broadened students' perceptions of engineering's relevance to their lives and potential careers. This study demonstrates the effectiveness of place-based education in nurturing engineering interest and aspirations, especially among rural and underrepresented students. The findings suggest that sustained, contextualized engineering activities play a crucial role in shaping students' understanding of engineering and fostering long-term career aspirations in the field. 

Cell communication via chemical signaling depends on spatial and temporal concentration changes. Nitric oxide (NO), a gaseous signaling molecule, is critical in physiological and pathological processes. However, current NO sensing methods lack the spatiotemporal resolution necessary to study subcellular NO efflux. This study introduces an innovative sensory platform utilizing single‐walled carbon nanotubes (SWNT) as an optical transducer for the spatial and temporal detection of extracellular NO. The platform quantifies NO diffusion gradients produced by human (THP‐1) and murine (RAW 264.7) macrophage cells. The uniform fluorescence distribution of the nanoarray enables precise analysis of NO efflux directionality, both under and surrounding the cell. It is demonstrated that cellular adhesion to the surface of the sensory platform does not affect its fluorescence functionality or sensing response rate. By combining the platform's high spatiotemporal resolution with the advanced analysis methods, the SWNT sensor platform offers a robust tool for studying extracellular NO dynamics within the cellular microenvironment. This work lays the foundation for advanced diagnostic and therapeutic tools elucidating NO cellular communication analysis. 

Progress has been made studying cell-cell signaling communication processes. However, due to limitations of current sensors on time and spatial resolution, the role of many extracellular analytes is still unknown. A single walled carbon nanotube (SWNT) platform was previously developed based on the avidin-biotin immobilization of SWNT to a glass substrate. The SWNT platform provides real time feedback about analyte concentration and has a high concentration of evenly distributed sensors, both of which are essential for the study of extracellular analytes. Unfortunately, this initial SWNT platform is synthesized through unsterile conditions and cannot be sterilized post-production due to the delicate nature of the sensors, making it unsuitable for in vitro work. Herein the multiple-step process for SWNT immobilization is modified and the platform’s biocompatibility is assessed in terms of sterility, cytotoxicity, cell proliferation, and cell morphology through comparison with non-sensors controls. The results demonstrate the SWNT platform’s sterility and lack of toxicity over 72 h. The proliferation rate and morphology profiles for cells growing on the SWNT platform are similar to those grown on tissue culture substrates. This novel nano-sensor platform preserves cell health and cell functionality over time, offering opportunities to study extracellular analytes gradients in cellular communication. 

Single-wall carbon nanotubes (SWNT) have a strong and stable near-infrared (nIR) signal and can interact with target analytes selectively, even at the single molecule level, to alter fluorescence intensity and/or emission peak wavelength. SWNT have been employed as nIR optical sensors for detecting a variety of analytes. However, high cost, long fabrication time, and poor fluorescence yield limit the current methods for immobilizing SWNT sensors on solid substrates. Recently, our group reported a protocol for SWNT immobilization resulting in high fluorescence yield, signal longevity, fluorescence distribution, and quick sensing response time. However, it takes 5 days to fabricate these sensor arrays. We have improved our previously reported protocol to immobilize SWNT sensors with a method that takes only 2 days, results in a platform with similar surface morphology, and has a higher fluorescence intensity than the previous platforms without sacrificing the sensing capabilities.