Exploring new type of synapse–like electronic devices with fusion of computing and memory is a promising strategy to fundamentally approach to intelligent machines. Herein, organic thin film ...memristors (OTFMs) are achieved, functioning as electrically programmable and erasable analog memory with continuous and nonvolatile device states. The memristive characteristics of OTFMs stem from the asymmetric electrode configuration and the cumulative charge trapping/detrapping in a polymer electret layer, which enables the state–dependent current modulation analogous to the synaptic weight change in biological synapses. OTFMs are demonstrated to successfully emulate the essential synaptic functions, including the reversible potentiation and depression, and the short‐term plasticity such as the paired‐pulse facilitation and the long‐term plasticity such as the spike–timing dependent plasticity.
Organic thin film memristors are achieved based on asymmetric electrode configuration and cumulative charge trapping/detrapping in a polymer electret layer, which function as electrically editable and preservable analog memory. Organic thin film memristors are demonstrated to be capable of emulating both short‐term and long‐term synaptic plasticity, such as the paired‐pulse facilitation and spike‐timing‐dependent plasticity.
With the rapid development of conductive polymers, they have shown great potential in room-temperature chemical gas detection, as their electrical conductivity can be changed upon exposure to ...oxidative or reductive gas molecules at room temperature. However, due to their relatively low conductivity and high affinity toward volatile organic compounds and water molecules, they always exhibit low sensitivity, poor stability, and gas selectivity, which hinder their practical gas sensor applications. In addition, inorganic sensitive materials show totally different advantages in gas sensors, such as high sensitivity, fast response to low concentration analytes, high surface area, and versatile surface chemistry, which could complement the conducting polymers in terms of the sensing characteristics. It seems to be a win-win choice to combine inorganic sensitive materials with polymers for gas detection due to their synergistic effects, which has attracted extensive interests in gas-sensing applications. In this review, we summarize the recent development in polymer-inorganic nanocomposite based gas sensors. The roles of inorganic nanomaterials in improving the gas-sensing performances of conducting polymers are introduced and the progress of conducting polymer-inorganic nanocomposites including metal oxides, metal, carbon (carbon nanotube, graphene), and ternary composites are presented. Finally, a conclusion and a perspective in the field of gas sensors incorporating conducting polymer-inorganic nanocomposite are summarized.
Cardiovascular disease (CVD) is highly prevalent in an ageing society. The increased incidence and mortality rates of CVD are global issues endangering human health. There is an urgent requirement ...for understanding the aetiology and pathogenesis of CVD and developing possible interventions for preventing CVD in ageing hearts. It is necessary to select appropriate models and treatment methods. The D‐galactose‐induced cardiac ageing model possesses the advantages of low mortality, short time and low cost and has been increasingly used in the study of cardiovascular diseases in recent years. Therefore, understanding the latest progress in D‐galactose‐induced cardiac ageing is valuable. This review highlights the recent progress and potential therapeutic interventions used in D‐galactose‐induced cardiac ageing in recent years by providing a comprehensive summary of D‐galactose‐induced cardiac ageing in vivo and in vitro. This review may serve as reference literature for future research on age‐related heart diseases.
Transparent flexible energy storage devices are limited by the trade‐off among flexibility, transparency, and charge storage capability of their electrode materials. Conductive polymers are ...intrinsically flexible, but limited by small capacitance. Pseudocapacitive MXene provides high capacitance, yet their opaque and brittle nature hinders their flexibility and transparency. Herein, the development of synergistically interacting conductive polymer Ti3C2Tx MXene/PEDOT:PSS composites is reported for transparent flexible all‐solid‐state supercapacitors, with an outstanding areal capacitance of 3.1 mF cm−2, a high optical transparency of 61.6%, and excellent flexibility and durability. The high capacitance and high transparency of the devices stem from the uniform and thorough blending of PEDOT:PSS and Ti3C2Tx, which is associated with the formation of O─H…O H‐bonds in the composites. The conductive MXene/polymer composite electrodes demonstrate a rational means to achieve high‐capacity, transparent and flexible supercapacitors in an easy and scalable manner.
The synergistically interacting Ti3C2Tx/PEDOT:PSS composite is reported for all‐solid‐state transparent flexible symmetric supercapacitors with an outstanding areal capacitance of 3.1 mF cm−2, a high optical transparency of 61.6%, and excellent flexibility and durability, which hold significant promise for wearable and portable energy storage applications.
Methoprene‐tolerant (Met) as an intracellular receptor of juvenile hormone (JH) and the Krüppel‐homolog 1 (Kr‐h1) as a JH‐inducible transcription factor had been proved to contribute to insect ...reproduction. Their functions vary in different insect orders, however, they are not clear in Psocoptera. In this study, LeMet and LeKr‐h1 were identified and their roles in vitellogenesis and ovarian development were investigated in Liposcelis entomophila (Enderlein). Treatment with exogenous JH III significantly induced the expression of LeKr‐h1, LeVg, and LeVgR. Furthermore, silencing LeMet and LeKr‐h1 remarkably reduced the transcription of LeVg and LeVgR, disrupted the production of Vg in fat body and the uptake of Vg by oocytes, and ultimately led to a decline in fecundity. The results indicated that the JH signaling pathway was essential to the reproductive process of this species. Interestingly, knockdown of LeMet or LeKr‐h1 also resulted in fluctuations in the expression of FoxO, indicating the complex regulatory interactions between different hormone factors. Besides, knockdown of both LeMet and LeKr‐h1 significantly increased L. entomophila mortality. Our study provides initial insight into the roles of JH signaling in the female reproduction of psocids and provided evidence that RNAi‐mediated knockdown of Met or Kr‐h1 is a potential pest control strategy.
Highlights
LeMet and LeKr‐h1 were identified in a Psocoptera insect.
Juvenile hormone (JH) signaling pathway significantly affected vitellogenesis of female Liposcelis entomophila.
Methoprene‐tolerant (Met) and Krüppel‐homolog 1 (Kr‐h1) could act as potential targets for RNAi‐mediated psocid control.
A graphical summary of this study and a model of the role of juvenile hormone (JH) signaling in the reproduction of Liposcelis entomophila. JH signaling induces reproduction by enhancing the expression of Vg through Met and Kr‐h1. Blocking JH signaling by knockdown with Met and Kr‐h1, which inhibits Vg expression and affects reproduction, can provide technical support for its control.
Highly structured RNA molecules usually interact with each other, and associate with various RNA-binding proteins, to regulate critical biological processes. However, RNA structures and interactions ...in intact cells remain largely unknown. Here, by coupling proximity ligation mediated by RNA-binding proteins with deep sequencing, we report an RNA in situ conformation sequencing (RIC-seq) technology for the global profiling of intra- and intermolecular RNA-RNA interactions. This technique not only recapitulates known RNA secondary structures and tertiary interactions, but also facilitates the generation of three-dimensional (3D) interaction maps of RNA in human cells. Using these maps, we identify noncoding RNA targets globally, and discern RNA topological domains and trans-interacting hubs. We reveal that the functional connectivity of enhancers and promoters can be assigned using their pairwise-interacting RNAs. Furthermore, we show that CCAT1-5L-a super-enhancer hub RNA-interacts with the RNA-binding protein hnRNPK, as well as RNA derived from the MYC promoter and enhancer, to boost MYC transcription by modulating chromatin looping. Our study demonstrates the power and applicability of RIC-seq in discovering the 3D structures, interactions and regulatory roles of RNA.
Minimizing reverse bias dark current density (Jdark) while retaining high external quantum efficiency is crucial for promising applications of perovskite photodiodes, and it remains challenging to ...elucidate the ultimate origin of Jdark. It is demonstrated in this study that the surface defects induced by iodine vacancies are the main cause of Jdark in perovskite photodiodes. In a targeted way, the surface defects are thoroughly passivated through a simple treatment with butylamine hydroiodide to form ultrathin 2D perovskite on its 3D bulk. In the passivated perovskite photodiodes, Jdark as low as 3.78 × 10‐10 A cm‐2 at ‐0.1 V is achieved, and the photoresponse is also enhanced, especially at low light intensities. A combination of the two improvements realizes high specific detectivity up to 1.46 × 1012 Jones in the devices. It is clarified that the trap states induced by the surface defects can not only raise the generation‐recombination current density associated with the Shockley–Read–Hall mechanisms in the dark (increasing Jdark), but also provide additional carrier recombination paths under light illumination (decreasing photocurrent). The critical role of surface defects on Jdark of perovskite photodiodes suggests that making trap‐free perovskite thin films, for example, by fine preparation and/or surface engineering, is a top priority for high‐performance perovskite photodiodes.
This work demonstrates that the trap states induced by surface iodine vacancies significantly contribute to the generation‐recombination current in the dark and thus to the reverse bias dark current of perovskite photodiodes. The insights into the ultimate origin of the dark current in perovskite photodiodes will be of great interest in perovskite electronics and optoelectronics.
Zinc oxide (ZnO) nanowires have attracted extensive interests in ultraviolet photodetection fields owing to their outstanding optoelectronic properties. The detectivity of ZnO nanowire photodetectors ...is often limited by large dark current due to a number of defect‐induced carriers. Herein, a thin layer of poly(2‐vinyl naphthalene) (PVN) is introduced between the ZnO nanowire and gate dielectric to deplete defect‐induced carriers with the help of the electrostatic field generated by trapped electrons in the PVN layer. The dark current is successfully reduced from 2.2 × 10−9 to 1.6 × 10−14 A. Particularly, ZnO nanowire photodetectors with a large Ilight/Idark ratio (>107), high photoresponsivity (>106 A W−1), and ultrahigh detectivity (>1018 Jones) are achieved, which are among the best performance in reported ZnO‐based photodetectors. The present simple scheme offers a new strategy to suppress dark current in semiconducting nanomaterials for ultrasensitive photodetection applications.
For minimizing the dark current of ZnO nanowire photodetectors, a thin layer of polymer electret, poly(2‐vinyl naphthalene), is inserted between the ZnO nanowire and gate dielectric to deplete defect‐induced carriers in the channel. Through this strategy, the dark current of the ZnO nanowire photodetectors can be significantly reduced (<10−13 A) and ultrahigh detectivity (>1018 Jones) is achieved.
Abstract
For the next generation of human‐machine interaction (HMI) systems, the development of a tactile interaction unit with multimodal, high sensitivity, and real‐time perception and recognition ...is the key. Herein, an artificial tactile near‐sensor computing (ATNSC) unit based on a triboelectric tactile sensor and an organic synaptic transistor is reported. By introducing multi‐peak microstructures, the mechanical performance of the tactile sensor is optimized, showing a high sensitivity of 0.98 V kPa
−1
in the pressure range of 0–10 kPa and maintaining 0.11 V kPa
−1
at high pressures up to 350 kPa. Additionally, by designing stripe‐like convex structures on the top surface, the sensor is capable of bimodal perception in both pressure and sliding sensations. Furthermore, the organic synaptic transistor, which can be driven by tactile sensing stimuli in a variety of circumstances, is achieved utilizing an ion‐rich gelatin dielectric covered by a hydrophobic polymer coating layer. The ATNSC unit well demonstrates the stimuli‐dependent short‐term memory effect, and it enables tactile near‐sensor computing for feature action recognition in an HMI system, laying a solid foundation for the construction of intelligent interaction devices.
A method for the copper‐catalyzed thioannulation of propynamides with sodium sulfide was developed for the synthesis of isothiazol‐3‐ones. The reaction involves a nucleophilic addition and an ...intramolecular cross‐dehydrogenative coupling reaction. The thioannulation features the use of an inexpensive and odorless sulfur source and easily prepared propynamides with excellent functional group tolerance.
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