No abstract

Field-effect transistors (FETs) are solid-state electrical devices featuring current sources, current drains and semiconductor channels through which charge carriers migrate. FETs can be inexpensive, detect analyte without label, exhibit exponential responses to surface potential changes mediated by analyte binding, require limited sample preparation and operate in real time. ImmunoFETs for protein sensing deploy bioaffinity elements on their channels (antibodies), analyte binding to which modulates immunoFET electrical properties. Historically, immunoFETs were assessed infeasible owing to ion shielding in physiological environments. We demonstrate reliable immunoFET sensing of chemokines by relatively ion-impermeable III-nitride immunoHFETs (heterojunction FETs) in physiological buffers. Data show that the specificity of detection follows the specificity of the antibodies used as receptors, allowing us to discriminate between individual highly related protein species (human and murine CXCL9) as well as mixed samples of analytes (native and biotinylated CXCL9). These capabilities demonstrate that immunoHFETs can be feasible, contrary to classical FET-sensing assessment. FET protein sensors may lead to point-of-care diagnostics that are faster and cheaper than immunoassay in clinical, biotechnological and environmental applications.

This Work-in-Progress (WIP) research paper investigates the decisions of first-year engineering students as they select, and on occasion, switch their intended engineering major. This work provides useful initial insight into their decision making to better inform our practices for recruitment and retention of engineering students. In order to better understand the choices that first-year engineering students make concerning their intended major, this paper aims to examine how these students shift their intended engineering discipline throughout an academic year. This paper will discuss results from an examination of initial major choice and possible major switch during the first year of an engineering program. Three surveys were administered (at the beginning, middle, and end of academic year) which asked students about their perceptions of engineering, what major they were currently enrolled in, and their confidence in this major discipline selection. Results from these surveys showed several trends, including patterns related to students who switch majors throughout their first year. Examination of these trends may aid in knowledge of student interests, motivations, and ultimately decision-making in engineering major selection. Retention of first-year engineering students is of critical importance to the health of an engineering program, and a better understanding of students' disciplinary choices during their first year of study may allow educators and advisor to better address issues of attrition.