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Abstract Carbon dots represent a rapidly advancing and expanding research field, with a large number of literature reports on their potential technological applications including those relevant to food safety. In this article, the dot samples prepared by the deliberate chemical functionalization of preexisting small carbon nanoparticles or by thermal carbonization of various organic precursors under different processing conditions are highlighted and critiqued for their similarities and differences in sample structure-morphology and properties, especially antimicrobial properties for their food safety–related uses. Also highlighted and discussed are representative recent examples for the use of dot samples to inactivate foodborne pathogens, disrupt biofilms or prevent their formation, and extend the shelf life of food products, which involve different antibacterial mechanisms. Some perspectives on the further development of the carbon dots–based/derived antimicrobial platform and related excellent application opportunities in food safety are provided. 

Carbon dots (CDots) are classically defined as small carbon nanoparticles with effective surface passivation, which, in the classical synthesis, has been accomplished by surface organic functionalization. CDot-like nanostructures could also be produced by the thermal carbonization processing of selected organic precursors, in which the non-molecular nanocarbons resulting from the carbonization are embedded in the remaining organic species, which may provide the passivation function for the nanocarbons. In this work, a mixture of oligomeric polyethylenimine and citric acid in the solid state was used for efficient thermal carbonization processing with microwave irradiation under various conditions to produce dot samples with different nanocarbon content. The samples were characterized in terms of their structural and morphological features regarding their similarity or equivalency to those of the classical CDots, along with their significant divergences. Also evaluated were their optical spectroscopic properties and their photoinduced antimicrobial activity against selected bacterial species. The advantages and disadvantages of the thermal carbonization processing method and the resulting dot samples with various features and properties mimicking those of classically synthesized CDots are discussed. 

The goal of this project is to argue for ethics as a necessary component of the institutional health. The authors offer an epidemiology of ethics for a large, metropolitan, very-high-research-activity (R1) university in the U.S. Where epidemiology of a pandemic looks at quantifiable data on infection and exposure rates, control, and broad implications for public health, an epidemiology of ethics looks to parallel data on those same themes. Their hypothesis is that knowing more about how undergraduates are exposed to ethics will help us understand to what extent they are infected with interest in ethics literacy, and potentially what immunity they develop against unethical and unprofessional conduct. These data also tell a story about the ethical health of institutions: to what extent its members are empowered to cultivate a culture of ethics and inoculated against ethical missteps. The authors argue that pro-ethics inoculation at research institutions is shaped by issues of complexity (space given to “hard” vs. “soft” skills within curricula), connotation (differences in meaning of “ethics” among and within disciplines), and collaboration (tensions between Ethics-Across-the-Curriculum and Ethics-In-the-Disciplines approaches to ethics). These issues make assessment of where ethics is taught all the more difficult. The methodology used in this project can readily be taken up by other institutions, with much to be learned from inter-institutional comparisons about the distribution of ethics across the curriculum and within the disciplines.