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Printed transistors have a wide range of applications, but the limited resolution of printing techniques (10-30 µm) has been a barrier to their utility and scalability. Previous works have relied on chemical processes or tedious post-processing to realize printed submicron channel lengths, limiting their applicability. Here, we show that capillary flow printing can create as-printed submicron carbon nanotube thin-film transistors (CNT-TFTs) without chemical modification or physical manipulation post-printing. We show that the approach can be used to print conducting, semiconducting, and insulating inks on different types of substrates (silicon, Kapton, and paper), and can be used to fabricate various TFT device architectures. Printed CNT-TFTs yielded on-currents of 1.12 mA/mm when back gated on Si/SiO2, and 490 µA/mm when side gated through ion gel on Kapton. Mechanical bending and sweep rate resilience of devices on Kapton show the wide utility of these printed devices for flexible applications. 

Predicting arbovirus re-emergence remains challenging in regions with limited off-season transmission and intermittent epidemics. Current mathematical models treat the depletion and replenishment of susceptible (non-immune) hosts as the principal drivers of re-emergence, based on established understanding of highly transmissible childhood diseases with frequent epidemics. We extend an analytical approach to determine the number of ‘skip’ years preceding re-emergence for diseases with continuous seasonal transmission, population growth and under-reporting. Re-emergence times are shown to be highly sensitive to small changes in low R0 (secondary cases produced from a primary infection in a fully susceptible population). We then fit a stochastic SIR (Susceptible-Infected-Recovered) model to observed case data for the emergence of dengue serotype DENV1 in Rio de Janeiro. This aggregated city-level model substantially over-estimates observed re-emergence times either in terms of skips or outbreak probability under forward simulation. The inability of susceptible depletion and replenishment to explain re-emergence under ‘well-mixed’ conditions at a city-wide scale demonstrates a key limitation of SIR aggregated models including those applied to other arboviruses. The predictive uncertainty and high skip sensitivity to epidemiological parameters suggest a need to investigate the relevant spatial scales of susceptible depletion and the scaling of microscale transmission dynamics to formulate simpler models that apply at coarse resolutions. Introduction: