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Soft‐solid photonic crystals (PCs) based on periodically ordered block copolymer (BCP) nanostructures demonstrate stimuli‐adaptive structural colors (SCs) and desirable mechanical properties suitable for reflective‐mode electric‐switching (E‐switching) displays. However, the low electrochemical stability and humidity‐dependent E‐switching performance of hygroscopic ionic salts, often employed for E‐field‐adaptive structural alteration, limit their applications. In this study, a low‐powered capacitive E‐switching BCP SC display with an organohydrogel (OH) humidity controller is proposed, where a bilayer of a BCP and a polymer blend with hygroscopic E‐field‐adaptive ionic salts is sandwiched between Au electrodes. The display reliably exhibits reversible full‐color E‐switching (100 on/off cycles) at operating voltages of +2.5 to −2 V within the ionic salts' electrochemical window at ≈50% humidity. A patchable and reusable OH serves as a water reservoir (with optimized geometries and dimensions) to improve the display's humidity tolerance, providing a target humidity (≈50%). The proposed display performs at ambient humidity lower than 60% for over 10 days because of the long water retention and mechanical integrity properties of OH. Additionally, the topologically micropatterned BCP PC allows lateral diffusion of ionic salts through the sides of the patterned domain under E‐field, facilitating E‐switching speeds of ≈30 s. [ABSTRACT FROM AUTHOR]

Structural color (SC) arising from a periodically ordered self‐assembled block copolymer (BCP) photonic crystal (PC) is useful for reflective‐mode sensing displays owing to its capability of stimuli‐responsive structure alteration. However, a set of PC inks, each providing a precisely addressable SC in the full visible range, has rarely been demonstrated. Here, a strategy for developing BCP PC inks with tunable structures is presented. This involves solution‐blending of two lamellar‐forming BCPs with different molecular weights. By controlling the mixing ratio of the two BCPs, a thin 1D BCP PC film is developed with alternating in‐plane lamellae whose periodicity varies linearly from ≈46 to ≈91 nm. Subsequent preferential swelling of one‐type lamellae with either solvent or non‐volatile ionic liquid causes the photonic band gap of the films to red‐shift, giving rise to full‐visible‐range SC correlated with the pristine nanostructures of the blended films in both liquid and solid states. The BCP PC palette of solution‐blended binary solutions is conveniently employed in various coating processes, allowing facile development of BCP SC on the targeted surface. Furthermore, full‐color SC paintings are realized with their transparent PC inks, facilitating low‐power pattern encryption. [ABSTRACT FROM AUTHOR]

Despite great advances in stimuli‐interactive displays, which can directly visualize pressure, temperature, and humidity, a single interactive display platform capable of quantitatively discriminating the dynamic variation of two stimuli has yet to be developed. Here, a tandem interactive sensing display demonstrates not only direct visualization of both pressure and temperature but also the quantitative de‐convolution of these two simultaneously varied stimuli. The tandem display consists of five polymer layers vertically stacked on a transparent substrate: a temperature‐responsive ionic polymer, field‐induced blue light‐emitting unit (1), conductive polymer electrode with a parallel gap, field‐induced orange‐light‐emitting unit (2), and topologically structured pressure‐responsive layer. Impedance change of the responsive layers upon dynamic temperature and pressure is monitored simultaneously, providing stimuli‐interactive electroluminescence of light‐emitting units (1) and (2), respectively, when an alternating current (AC) field is applied between two polymer electrodes. Dynamic and simultaneous variation of temperature, 30–80 °C, and pressure, 0.5–20 kPa, are conveniently mapped in 3D coordinates of light intensity (z‐axis) and color (x‐y plane), producing a 2D contour surface plot. This provides an efficient and quantitative de‐convolution of unknown combinations of temperature and pressure stimuli. Furthermore, arrays of the tandem interactive displays broaden the versatility of dynamic visualization of multiple stimuli. [ABSTRACT FROM AUTHOR]

Flexible electronics that enable the visualization of thermal energy have significant potential for various applications, such as thermal diagnosis, sensing and imaging, and displays. Thermo‐adaptive flexible electronic devices based on thin 1D block copolymer (BCP) photonic crystal (PC) films with self‐assembled periodic nanostructures are presented. By employing a thermo‐responsive polymer/non‐volatile hygroscopic ionic liquid (IL) blend on a BCP film, full visible structural colors (SCs) are developed because of the temperature‐dependent expansion and contraction of one BCP domain via IL injection and release, respectively, as a function of temperature. Reversible SC control of the bi‐layered BCP/IL polymer blend film from room temperature to 80 °C facilitates the development of various thermo‐adaptive SC flexible electronic devices including pixel arrays of reflective‐mode displays and capacitive sensing display. A flexible diagnostic thermal patch is demonstrated with the bi‐layered BCP/IL polymer blend enabling the visualization of local heat sources from the human body to microelectronic circuits. [ABSTRACT FROM AUTHOR]

Abstract: We cloned a plant gene, Ntcyc07, conferring arsenite tolerance by expressing a tobacco expression library in WT yeast (Y800). Expression of Ntcyc07 increased the tolerance to As(III) and decreased its accumulation, suggesting that the enhanced As(III) tolerance resulted from a reduction of the intracellular arsenic level. Interestingly, expression of Ntcyc07 increased the expression of the As(III) export carrier ACR3, but repressed that of As(III) uptake channel FPS1. Ntcyc07p interacted with Acr1p, which is the transcriptional activator of ACR3, but not with the ACR3 promoter. Taken together, the data indicated that Ntcyc07p promoted As(III) tolerance by decreasing the intracellular level of As(III) via increasing the expression of ACR3 and reducing that of FPS1. [Copyright &y& Elsevier]

Abstract: MSN1 is a putative yeast transcriptional activator involved in chromium (Cr) accumulation. Here we show that overexpression of MSN1 enhances Cr and sulfur accumulation and Cr tolerance in transgenic tobacco. In addition, we found that expression of NtST1 (Nicotiana tabacum sulfate transporter 1) was elevated in MSN1- expressing transgenic tobacco, suggesting that chromate and sulfate are taken up via the sulfate transporter in plants. Supporting this, expression of NtST1 increased levels of Cr and S in Saccharomyces cerevisiae. Our findings suggest that yeast transcriptional activators can be used for developing effective metal remediators, and for improving the nutritional status of plants. [Copyright &y& Elsevier]

Tandem Interactive Sensing Displays: Tandem Interactive Sensing Display De-Convoluting Dynamic Pressure and Temperature (Adv. Funct. Alternating current electroluminescence, de-convolution, pressure, temperature, simultaneous displays, solid-state cathode luminescence, tandem interactive sensing displays Keywords: alternating current electroluminescence; de-convolution, pressure, temperature; simultaneous displays; solid-state cathode luminescence; tandem interactive sensing displays EN alternating current electroluminescence de-convolution, pressure, temperature simultaneous displays solid-state cathode luminescence tandem interactive sensing displays 1 1 1 06/07/21 20210615 NES 210615 In article number 2010492, Cheolmin Park and co-workers develop a tandem stimuli-interactive sensing display, allowing for not only direct visualization of both pressure and temperature but also quantitative de-convolution of the simultaneously varied stimuli, making the simple but multi-mode sensing display platform with a tandem architecture suitable for a variety of human interactive and health monitoring systems. [Extracted from the article]