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The development of a reliable optoelectronic memristor is crucial for the success of neuromorphic vision systems, but current devices are limited by stochastic resistance switching and uncontrollable ion dynamics. To address these challenges, a core–shell nanosphere composite was synthesized using CsPbBr3 quantum dots and block copolymer polystyrene-poly2-vinyl pyridine. This memristor exhibits both negative differential resistance and resistive switching memory behavior and has demonstrated exceptional stability, withstanding over 5000 cycles and remaining stable for over 5 million seconds. It is also tunable by light irradiation, making it ideal for optoelectronic logic operations and multi-derivative state applications. The memory behavior is attributed to an electrochemical metalization mechanism involving the formation and annihilation of pyridine groups, conductive metal filaments, and bromide ion vacancies in S2VP filaments. This work presents an effective method for fabricating robust multi-derivative perovskite optoelectronic devices for neuromorphic computing systems. Additionally, machine learning algorithms have demonstrated accurate digital image classification and recognition using photoelectric pulse-driven neuromorphic computation with an accuracy of over 97%. [ABSTRACT FROM AUTHOR]

According to Moore's Law's development law, traditional floating gate memory is constrained by charge tunneling, and its size is approaching the physical limit, which is insufficient to meet the requirements of large data storage. The introduction of new information storage devices may be the key to overcoming the bottleneck. Resistive random access memory (RRAM) has garnered interest due to its fast switching speed, low power consumption, and high integration density. The resistive switching (RS) behaviors can be demonstrated in many materials, including transition metal oxides, perovskite oxides and organic matter, etc. Among these materials, graphene oxide (GO) with its unique physical, chemical properties and excellent mechanical properties is attracting significant attention for use in RRAM owing to its RS operation and potential for integration with other graphene-based electronics. However, there is unacceptable variability in RS reliability, including retention and endurance, which is the key factor that affects the development of memristors. In addition, the RS mechanism of GO-based RRAM has not been systematically discussed. In this article, we discuss systematically several typical models of the switching mechanism of GO-based RRAM and a summary of methods for improving the device's RS performance. This article concludes by discussing the applications of GO-RRAM in artificial neural networks, flexible devices, and biological monitoring. [ABSTRACT FROM AUTHOR]

Current resistive access memories (RRAM) suffer from severe resistive switching variability issues due to the large stochasticity in the formation and disruption process of conductive filaments. Here, a material strategy is applied in designing an RRAM device that can substantially improve the switching uniformity by utilizing a silver imidazole complex as the switching medium. In the silver imidazole, Ag species has a moderate reduction Gibbs energy which can participate in the redox reaction to change the resistance state of the device. Moreover, as a resistive layer, the migration range of silver ions is limited in the grain of silver imidazole, which shortens the migration distance of silver ions and reduces the randomness caused by silver ion migration, thus improving the uniformity and stability of the device. Through this facile material engineering strategy, the RRAM exhibits enhanced performance with low spatial variation of 7.86%, low temporal variation of 1.78% and low operation voltage of 0.50 V. The high switching uniformity of silver imidazole RRAM allows us to employ them as building blocks for logic gates with high yield. The self‐reduction and grain boundary confinement effect of switching materials for RRAM design may open the way to the development of large‐scale circuits for non‐volatile computing and machine learning. [ABSTRACT FROM AUTHOR]

[Objective] Observe effects of Didang Qigui decoction on crystalline lens, lens epithelial cells and the level of HSP70 in rats with streptozotocin induced diabetic cataract. [Methods] 10 SD rats were randomly selected as the blank control group, and the rest of rats were injected 60 mg/kg of streptozotocin(STZ) into the enterocoelia at one time to reproduce diabetic rats models. 55 of the model animals were selected and randomly divided into model group, diamicron group, Didang Qigui decoction group, Didang Qigui decoction high dose group, Didang Qigui decoction and diamicron group, and corresponding interference was given to each group respectively. Turbidity of the lens was examined under the slit lamp respectively at 2, 4, 6, 8 week; after 8 weeks, morphologic changes of crystalline lens were observed under the microscope, and the expressions of HSP70 in lens epithelial cells(LEC) were detected. [Results] Crystalline lens of rats in the blank control group were always transparent and complete. Those of rats in the model group were gradually changed until becoming complete turbid. The rest of treatment groups with turbidity degree of rats' lens from heavy to light were Didang Qigui decoction high dose group, Didang Qigui decoction group, diamicron group, and Didang Qigui decoction and diamicron group. Forms of HE staining lens epithelial cells were also changed. If rats in the blank control group were taken as standards, expressions of HSP70 in LEC of crystalline lens in the model group gradually rose. In the treatment groups, the rate of HSP70 positive expression of rats in the Didang Qigui decoction high dose group was higher than that rate in diamicron group, idang Qigui decoction group, and Didang Qigui decoction and diamicron group. The discrepancy was very obvious (P < 0. 05). [Conclusions] By reducing blood glucose, gathering of sugar metabolites and osmotic pressure in crystalline lens, Didang Qigui decoction can effectively protect lens injury in experimental diabetic rats and inhibit the occurrence and development of cataract in diabetic rats, so it exerts certain preventive and therapeutic effects on early diabetic cataract in rats. [ABSTRACT FROM AUTHOR]

As one key issue of resistive switching (RS) memory, the cycling endurance is poorly understood in hybrid perovskite‐based memory devices. Here, the cycling failure and the corresponding cycling‐induced degradation of CH3NH3PbI3‐based resistive random access memory devices are discussed. The high resistance state clearly decreases with the number of operation cycles, finally triggering irreversible failure in the collapse of switching window. By monitoring the I–V curves for all cycles, a negative set event is observed to be the critical turning point that considerably accelerates the cycling degradation rate. The decrease of |Vset| and |Vreset| indicates a reduction of the migration barrier of iodine vacancies (VI), which accounts for the appearance of a negative set after cycling. The understanding of RS cycling degradation can promote the optimization of device endurance by slowing the defect accumulation rate. The endurance degradation of CH3NH3PbI3‐based RRAM is attributed to the excessive defect accumulation during cycling operation. During the reset process, a negative set event is observed to accelerate the endurance degradation rate. Moreover, the decrease of transition voltages suggests a reduction of the migration barrier of iodine vacancies with cycling operation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression of nephrin mRNA in adriamycin-induced nephropathy (AN) in rats, and to explore the effect of Qufengtongluo recipe on proteinuria in AN rats and on the expression of nephrin mRNA., Methods: Adriamycin nephropathy was induced by a single tail intravenous injection of adriamycin. We randomly divided 140 rats into a normal control group (n=32) and a nephropathy model group (n=108). Three weeks later, 90 AN rats were randomly divided into 5 groups: a model group, a qufeng group, a qufeng and prednisone group, a prednisone group, and a benazepri group (18 rats in each group). They were treated respectively, and renal tissue samples were collected at week 0, 3, 5, and 7, respectively. The distribution and expression of nephrin mRNA were examined by indirect immunofluorescence and semi-quantity RT-PCR., Results: In the AN rats, the diffuse fusion and effacement of foot processes were observed at week 3. The fluorescence intensity of nephrin and the expression of nephrin mRNA significantly increased in the qufeng group and the prednisone group compared with the model group at the week 7 (P<0.01)., Conclusion: Abnormal expression of nephrin is the important molecular mechanism that leads to the occurrence and development of proteinuria in AN rats. Qufengtongluo recipe has effect on nephrotic syndrome through altering the expression and distribution of nephrin in glomerulus.