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Resolving global problems (e.g., climate change) requires decision-makers who can see problems through an intersection of disciplines and perspectives, and identify the root causes of disparate and inequitable outcomes between groups. As such, there is an urgent need to develop systems-thinking skills in learners so that they are able to address the interdisciplinarity and intersectionality fundamental to complex socio- scientific challenges when acting as decision-makers. This session highlights how storytelling can be used as a pedagogical approach to building systems-thinking and collaboration skills in informal learning environments. Research presented include examples of how podcasts, graphic novels, and theatre can be used as storytelling approaches. This interactive session brings together scholars who work in community- based partnerships around North America, India, and Bhutan. 

Super resolution microscopy (SRM) brings the advantages of optical microscopy to the imaging of nanostructured soft matter, and in colloidal microgels, promises to quantify variations of crosslink densities at unprecedented length scales. However, the distribution of all crosslinks does not coincide with that of dye-tagged crosslinks, and density quantification in SRM is not guaranteed due to over/under-counting dye molecules. Here we demonstrate that SRM images of microgels encode reaction rate constants of functional cross linkers, which hold the key to correlating these distributions. Combined with evolution of microgel particle radii, the functional cross linker distributions predict consumption versus time with high fidelity. Using a Bayesian regression approach, we extract reaction rate constants for homo and cross propagation of the functional crosslinker, which should be widely useful for predicting spatial variations in crosslink density of gels. 

Highly parallelized optical super-resolution lithography techniques are key for realizing bulk volume nanopatterning in materials. The majority of demonstrated STED-inspired lithography schemes are serial writing techniques. Here we use a recently developed model spirothiopyran monolayer photoresist to study the non-equilibrium kinetics of STED-inspired lithography systems to achieve large area interference lithography with super-resolved feature dimensions. The linewidth is predicted to increase with exposure time and the contrast is predicted to go through a maximum, resulting in a narrow window of optimum exposure. Experimental results are found to match with high quantitative accuracy. The low photoinhibition saturation threshold of the spirothiopyran renders it especially conducive for parallelized large area nanopatterning. Lines with 56 and 92 nm FWHM were obtained using serial and parallel patterning, respectively. Functionalization of surfaces with heterobifunctional PEGs enables diverse patterning of any desired chemical functionality on these monolayers. These results provide important insight prior to realizing a highly parallelized volume nanofabrication technique. 

To fulfill the insatiable demand for high data-rates, the millimeter-wave (mmW) 5G communication standard will extensively use high-order complex-modulation schemes (e.g., QAM) with high peak-to-average power ratios (PAPRs) and large RF bandwidths. High-efficiency integrated CMOS power amplifiers (PA) are highly desirable for portable devices for improved battery life, reduced form factor, and low cost. To meet simultaneous requirements for high efficiency and reasonable linearity, PAs intended for use with complex modulation are often operated in Class-AB mode [1,2]. For small input amplitude in Class-AB, the device is turned-on and has an input capacitance (Cgs) of ~(2/3)WLCox. As the input amplitude becomes large, the device turns-off for part of the RF cycle, thus reducing its effective input capacitance. This input capacitance-modulation effect creates an input-amplitude-dependent phase shift in Class-AB mode resulting in an amplitude-modulation to phase-modulation (AM-PM) distortion [2]. Consequently, it degrades linearity metrics (e.g., error vector magnitude (EVM), adjacent channel power ratio (ACPR)) in complex-modulation systems. External linearization techniques (e.g., digital pre-distortion) are often used in transmitters to meet linearity requirements, but they are complex in nature and expensive to implement. Apart from these, few works at low-GHz frequencies are reported to improve the PA's intrinsic linearity using a varactor-or PMOS-based AM-PM correction methods [1,2]. These works reduce the design overhead of external linearization systems; however, the inclusion of additional capacitive element to correct AM-PM degrades gain and efficiency, which is not optimal for mmW frequencies 

Twenty-four centrifuge model tests have been conducted at nine different geotechnical centrifuge facilities around the world as part of the international LEAP effort (liquefaction experiments and analysis projects). All of the centrifuge models represent a 4 m deep 5 degree sloping submerged sand deposit. The mean effective PGA of the input motion for all of the experiments was approximately 0.15 g and the mean relative density was approximately 65%, but the effective PGA’s varied between about 0.07 g and 0.3 g, and the relative densities varied between about 40% and 75%. The test matrix was designed to enable experimental quantification of not only the median response but also the trend and sensitivity of the model response to density and shaking intensity. Quantification of the sensitivity of the response to initial conditions is a prerequisite for objective evaluation of the quality of the model test data. In other words, a discrepancy between two experiments should be evaluated after accounting for the uncertainty in the initial conditions and the sensitivity of the response to initial conditions. For the first time, a sufficient number of experiments has been performed on a similar problem to provide meaningful quantitative evaluation of the trend between PGA, density, and displacement. The sensitivity is quantified by the gradient of the trend and the uncertainty of the trend is quantified from the residuals between the fitting data and the trend. 

The majority of gels exhibit nanoscale spatial variations in crosslink density. We present the first 3D super-resolution microscopy images of dye tagged cross-link distributions in microgels and hydrogels. The morphology of nanoscale features never imaged previously in microgels, are revealed.