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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. 

Detailed studies of hot subdwarf B (sdB) stars with red dwarf (dM) or brown dwarf (BD) companions can shed light on the effects of binarity on late stellar evolution. Such systems exhibit a strong, quasi-sinusoidal reflection effect due to irradiation of the cool companion, and some even show primary and secondary eclipses. For this work, we computed Fourier transforms of TESS light curves of sdB+dM/BD binaries and investigate correlations between the relative amplitudes and phases of their harmonics and system parameters. We show that the reflection effect shape strongly depends on the orbital inclination, with nearly face-on systems having much more sinusoidal shapes than nearly edge-on systems. This information is encoded by the relative strength of the first harmonic in the Fourier transform. By comparing observations of solved systems to synthetic light curves generated bylcurve, we find that the inclination of non-eclipsing systems with high signal-to-noise light curves can be determined to within ≈10° simply by measuring their orbital periods and first harmonic strengths. We also discovered a slight asymmetry in the reflection effect shape of sdB+dM/BD binaries using the relative phase of the first harmonic. From our analysis of synthetic light curves, we conclude the asymmetry results from relativistic beaming of both stellar components. This marks the first time Doppler beaming has been detected in sdB+dM/BD systems. Although advanced modeling is necessary to quantify the effects of secondary parameters, such as limb darkening, the temperature ratio, and the radius ratio on the reflection effect shape, our pilot study demonstrates that it might be possible to extract both the inclination angle and cool companion velocity from the light curves of non-eclipsing systems. 

Blind and low-vision (BLV) people rely on GPS-based systems for outdoor navigation. GPS's inaccuracy, however, causes them to veer off track, run into obstacles, and struggle to reach precise destinations. While prior work has made precise navigation possible indoors via hardware installations, enabling this outdoors remains a challenge. Interestingly, many outdoor environments are already instrumented with hardware such as street cameras. In this work, we explore the idea of repurposing *existing* street cameras for outdoor navigation. Our community-driven approach considers both technical and sociotechnical concerns through engagements with various stakeholders: BLV users, residents, business owners, and Community Board leadership. The resulting system, StreetNav, processes a camera's video feed using computer vision and gives BLV pedestrians real-time navigation assistance. Our evaluations show that StreetNav guides users more precisely than GPS, but its technical performance is sensitive to environmental occlusions and distance from the camera. We discuss future implications for deploying such systems at scale. 

X-ray detectors are commonly used for medical, crystallography and space physics applications. Most of the current x-ray detectors use cadmium zinc telluride (CZT) as the active medium. This report investigates high density semiconducting and scintillating glasses as potential alternatives to CZT. For the semiconducting glasses, samples composed of xCuO–((1−x)/2)PbO–((1−x)/2)V2O5 and xFeO–((1−x)/2)PbO–((1−x)/2)V2O5, for the scintillating glasses, samples composed of xGd2O3+yWO3+(1−x−y)2H3BO3, doped with 1–6% Eu3+ or Tb3+, were investigated in this study. The glass-making conditions, density, Raman spectroscopy analysis, photoluminescence excitation and emission spectra, as well as conductivity measurements performed on various samples, are reported. The interaction of x-rays with all the glass samples was simulated using GATE software, and their mass attenuation coefficients were calculated and compared with CZT. 

Blind and low-vision (BLV) people rely on GPS-based systems for outdoor navigation. GPS’s inaccuracy, however, causes them to veer off track, run into obstacles, and struggle to reach precisedestinations. While prior work has made precise navigation possible indoors via hardware installations, enabling this outdoors remains a challenge. Interestingly, many outdoor environments are already instrumented with hardware such as street cameras. In this work, we explore the idea of repurposing existing street cameras for outdoor navigation. Our community-driven approach considers both technical and sociotechnical concerns through engagements with various stakeholders: BLV users, residents, business owners, and Community Board leadership. The resulting system, StreetNav, processes a camera’s video feed using computer vision and gives BLV pedestrians real-time navigation assistance. Our evaluations show that StreetNav guides users more precisely than GPS, but its technical performance is sensitive to environmental occlusions and distance from the camera. We discuss future implications for deploying such systems at scale. 

Although smell influences many daily activities, researchers and practitioners have yet to thoroughly understand smells and the interactions involved in smell mixtures. We present work focused on artificially synthesizing odor mixtures, the evaluation techniques to measure the fidelity of such technologies, and the rich application scenarios that materialize with this capability. We highlight our system implementation and design considerations for an olfactory wearable for odor mixing. Then, we outline an approach to assess odor mixing behavior and efficacy, and finally, we discuss possible studies to contextualize the usefulness of our technology. 

Abstract Neuromorphic sensors have inherently‐fast speeds and low data rates, which potentially make them ideal for the observation of transient sources, such as lightning and sprites. Particularly, for remote observations. In this article, we report the first observations of sprites from the ground with a neuromorphic sensor. These observations are accompanied by measurements with established instruments such as low‐light level and high‐frame rate cameras. We determine that neuromorphic sensors can capture sprites and determine their duration to an accuracy of roughly 6 ms. Average sprite durations were found to be 55 ms within our data set. We have also ascertained that sprites may be too dim for the neuromorphic sensors to resolve the internal spatiotemporal dynamics, at least without the aid of intensifiers.