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  1. Wastewater surveillance for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging approach to help identify the risk of a coronavirus disease (COVID-19) outbreak. This tool can contribute to public health surveillance at both community (wastewater treatment system) and institutional (e.g., colleges, prisons, and nursing homes) scales. This paper explores the successes, challenges, and lessons learned from initial wastewater surveillance efforts at colleges and university systems to inform future research, development and implementation. We present the experiences of 25 college and university systems in the United States that monitored campus wastewater for SARS-CoV-2 during the fall 2020 academic period. We describe the broad range of approaches, findings, resources, and impacts from these initial efforts. These institutions range in size, social and political geographies, and include both public and private institutions. Our analysis suggests that wastewater monitoring at colleges requires consideration of local information needs, sewage infrastructure, resources for sampling and analysis, college and community dynamics, approaches to interpretation and communication of results, and follow-up actions. Most colleges reported that a learning process of experimentation, evaluation, and adaptation was key to progress. This process requires ongoing collaboration among diverse stakeholders including decision-makers, researchers, faculty, facilities staff, students, and community members. 
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  2. Hot electron transport from single gold nanoantennas to underlying monolayer molybdenum disulfide (MoS2) is examined using electron energy loss spectroscopy (EELS). EELS allows nanometer‐scale resolution and avoids confounding effects of optical excitation. Experimental EELS measures of plasmon bandwidth in the presence and absence of MoS2are compared with calculated bandwidth contributions from radiative, nonradiative, and interfacial damping. Transport of plasmon hot electrons from 80 nm gold nanospheres to underlying MoS2is estimated. A 6 ± 1% hot electron transport quantum efficiency is inferred from a measured 0.08 eV increase in plasmon damping in the presence of MoS2. Hot electron transport can contribute to reported enhancements in catalysis and photodetection of MoS2decorated with gold nanoantennas. Improved understanding of resonant electric interactions between noble metal nanoantennas and transition metal dichalcogenides can benefit emerging optoelectronics.

     
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