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Not AvailableFlexible optoelectronic systems face fundamental challenges, including scalable synthesis of uniform, high-performance semiconductors and sensitivity to defects from large-area fabrication. Low-temperature deposition of perovskites, organics, and compound semiconductors promises tunable absorption but introduces structural disorder and sub-gap states that degrade device metrics. Here, we harness electronic disorder in printed sensors via machine learning to decode the photoresponse of three-terminal indium oxysulfide phototransistors fabricated by vacuum-free liquid metal interfacial synthesis. These devices combine wafer-scale uniformity with broadband visible absorption, achieving responsivities >100 A/W and detectivities approaching 7 × 1013 Jones. A cascaded classifier-regressor trained on gate-dependent photocurrent decodes illumination wavelengths (>95% accuracy) and intensities (10 μW/cm2–10 mW/cm2) from a single voltage sweep—without filters or device arrays. To our knowledge, this is the first phototransistor to extract both color and brightness simultaneously. Exploiting disorder to reveal latent information enables low-cost, single-device sensing and multi-parameter detection in flexible electronics. 

Abstract Nanostructured epoxy composite resins have broad usage in adhesives, coatings, composites, and 3D printing. With these materials, careful control of the rheological properties is critical to ensuring that the properties meet their required performance targets. However, it can be difficult to accurately measure the rheological properties. In this work, we establish a method to develop a reliable pre-shear (PS) procedure to repeatably measure the apparent yield stress of the resins, which is critical to ensure the accurate understanding of the material behavior. The resins in this study consisted of an epoxy resin with nanoclay as a shear thinning agent, ionic liquid (1-ethyl-3-methylimidazolium dicyanamide) as a latent curing agent, and poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) block copolymer (BCP) as a nanostructured component. We establish a methodology to evaluate the effectiveness of a pre-shear protocol and evaluate several methods to identify a pre-shear procedure that resulted in repeatable transient creep results on a rheometer. We identified that large amplitude oscillatory shear was the most effective method for these materials, and the optimal magnitude of the shear was dependent on the composition of the epoxy resins. Through the consistent application of this approach, we were able to use transient creep testing to identify the phase boundaries in the epoxy/BCP resins when the BCP micelles undergo an order-order transition from spherical to hexagonal micelles through changes in the yield stress of the material. This work adds to the new growing body of literature demonstrating the importance of establishing rigorous pre-shear conditions to improve the accuracy of structured yield stress fluids. 

Abstract Broader adoption of 4D ultrafast electron microscopy (UEM) for the study of chemical, materials, and quantum systems is being driven by development of new instruments as well as continuous improvement and characterization of existing technologies. Perhaps owing to the still‐high barrier to entry, the full range of capabilities of laser‐driven 4D UEM instruments has yet to be established, particularly when operated at extremely low beam currents (~fA). Accordingly, with an eye on beam stability, we have conducted particle tracing simulations of unconventional off‐axis photoemission geometries in a UEM equipped with a thermionic‐emission gun. Specifically, we have explored the impact of experimentally adjustable parameters on the time‐of‐flight (TOF), the collection efficiency (CE), and the temporal width of ultrashort photoelectron packets. The adjustable parameters include the Wehnelt aperture diameter (D_W), the cathode set‐back position (Z_tip), and the position of the femtosecond laser on the Wehnelt aperture surface relative to the optic axis (R_photo). Notable findings include significant sensitivity of TOF toD_WandZ_tip, as well as non‐intuitive responses of CE and temporal width to varyingR_photo. As a means to improve accessibility, practical implications and recommendations are emphasized wherever possible. 

The nonlinear response of yield stress fluids remains difficult to predict and control. Here, we show that the height of the overshoot in the loss modulus G00, a key characteristic of yielding, depends only on linear viscoelastic properties. Furthermore, the position of this overshoot depends on linear viscoelastic and flow properties, demonstrating the important and enduring role of elasticity in yielding. The physics governing linear viscoelasticity is therefore not only preserved during yielding but also controls two commonly reported yielding metrics. 

Two-dimensional (2D) metal oxide semiconductors offer a superlative combination of high electron mobility and visible-range transparency uniquely suitable for flexible transparent electronics. Synthesis of these ultrathin (<3 nm) semiconductors by Cabrera-Mott oxidation of liquid metals could enable emerging device applications but requires the precise design of their electrostatics at the nanoscale. This study demonstrates sub-nanometer-level control over the thickness of semiconducting 2D antimony-doped indium oxide (AIO) by manipulating the kinetics of Cabrera-Mott oxidation through variable-speed liquid metal printing at plastic-compatible temperatures (175°C). By modulating both the growth kinetics and doping, we engineer the conductivity and crystallinity of AIO for integration in ultrathin channel transistors exhibiting exceptional steep turn-on, on-off ratios > 106 and an outstanding average mobility of 34.7 ± 12.9 cm2/Vs. This result shows the potential for kinetically controlling 2D oxide synthesis for various high-performance optoelectronic device applications. 

ABSTRACT Leaves are critical to plant photosynthesis and the loss of leaf area can have negative consequences for an individual's performance and fitness. Variation in plant defenses plays a large role in protecting their leaves from attack by insect herbivores. However, trade‐offs in allocation among growth, reproduction, and defense may limit the availability of resources for any one aspect of a plant's life‐history strategy, which would lead to greater herbivory in those plants that allocate more resources to growth or reproduction than to defense. Patterns of sex‐biased herbivory in dioecious plants are well documented yet are known to vary in the direction (female or male) of their bias. A greater concentration of conspecifics may also increase herbivore attack through negative density dependence. In order to test the hypothesis that sex‐biased herbivory varies as a function of conspecific density, we measured standing herbivory on 2350 leaves on 302 trees of the dioecious understory treeIryanthera hostmannii(Myristicaceae) situated in a large forest dynamics plot in a lowland tropical rain forest in Ecuador. We found no difference in standing herbivory between the 169 male and 133 female trees, nor for focal trees surrounded by higher densities of conspecifics. The slow‐growing, shade‐tolerant growth patterns ofI. hostmanniimay contribute to suppressed differential expression of secondary sex characters in leaf defenses, leading to similar levels of herbivory between males and females. Considering the factors that most strongly affect herbivory in dioecious species is important in understanding the evolution of sex‐related traits more broadly.