Truly Concomitant and Independently Expressed Short‐ and Long‐Term Plasticity in a Bi2O2Se‐Based Three‐Terminal Memristor

Concomitance of diverse synaptic plasticity across different timescales produces complex cognitive processes. To achieve comparable cognitive complexity in memristive neuromorphic systems, devices that are capable of emulating short‐term (STP) and long‐term plasticity (LTP) concomitantly are essential. In existing memristors, however, STP and LTP can only be induced selectively because of the inability to be decoupled using different loci and mechanisms. In this work, the first demonstration of truly concomitant STP and LTP is reported in a three‐terminal memristor that uses independent physical phenomena to represent each form of plasticity. The emerging layered material Bi₂O₂Se is used for memristors for the first time, opening up the prospects for ultrathin, high‐speed, and low‐power neuromorphic devices. The concerted action of STP and LTP allows full‐range modulation of the transient synaptic efficacy, from depression to facilitation, by stimulus frequency or intensity, providing a versatile device platform for neuromorphic function implementation. A heuristic recurrent neural circuitry model is developed to simulate the intricate “sleep–wake cycle autoregulation” process, in which the concomitance of STP and LTP is posited as a key factor in enabling this neural homeostasis. This work sheds new light on the development of generic memristor platforms for highly dynamic neuromorphic computing.     

X-PLY超强瓦楞纸板动态缓冲特性的试验研究

基于跌落冲击试验,研究X-PLY(A)、X-PLY(B)两种超强瓦楞纸板的动态缓冲性能,获得了动态缓冲特性曲线的经验公式及其特征系数,为X-PLY超强瓦楞纸板在缓冲包装中的推广应用提供了基本数据.结果表明,X-PLY超强瓦楞纸板的动态缓冲特性曲线呈凹谷状,开口向上,只有一个极小值点,冲击加速度波形近似于半正弦波,具有优良的动态缓冲特性,而且X-PLY(A)超强瓦楞纸板的动态缓冲性能比X-PLY(B)超强瓦楞纸板更好.     

聚碳酸亚乙酯多元醇制备湿固化聚氨酯热熔胶及其性能研究

以聚碳酸亚乙酯多元醇(PEC)、二苯基甲烷4,4'-二异氰酸酯(MDI)和1,4-丁二醇(BDO)为主要原料,采用预聚物法合成了一种新型的湿固化聚氨酯热熔胶,并用聚四氢呋喃二醇(PTMG)型和聚己内酯二醇(PCL)型湿固化聚氨酯热熔胶进行性能比较.结果表明,热熔胶中多元醇种类、催化剂及异氰酸根(-NCO)含量对热熔胶的性能有较大的影响.用预聚物法合成的PEC型聚氨酯热熔胶具有较好的拉伸强度、粘接强度、耐水性能和可生物降解性,是一种新型环保粘接材料.     

Self-assembly synthesis of cactuslike Cu2O 3D nanoarchitectures via a low-temperature solution approach

Cu₂O nanocactuses were synthesized via a simple, low-temperature, and no time-consuming wet chemical route. The synthesized products were systematically studied by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the formation of Cu₂O nanocactuses was strongly depended on the addition of CTAB and NaOH. The structural evolution of the cactuslike Cu₂O was found to follow dissolution and recrystallization processes. It is noteworthy that the stepwise synthetic procedure was crucial to the growth of the final nanoarchitectures. UV–vis spectrum was also used to estimate the absorption and photodegradation ability of the nanocactuses.     

Modulating lateral strain in GaN-based epitaxial layers by patterning sapphire substrates with aligned carbon nanotube films

A novel carbon nanotube-patterned sapphire substrate (CPSS) has been utilized for the growth of GaN material and fabrication of a InGaN/GaN light emitting diode (LED) by metal-organic vapor phase epitaxy. Different lateral strain distributions and stress reductions were observed in a GaN thin film on CPSS compared with those on a conventional sapphire substrate. Nanoheteroepitaxy induced by small size nucleation islands of about 50 nm is ascribed to this significant strain modulation. The crystalline quality of the GaN thin film was also improved, as illustrated by X-ray diffraction. Performances of 1 mm × 1 mm LEDs on CPSS were also enhanced, with an operational power increase of 37.5% and higher saturation current.      

FPGA芯片的多路模拟信号源设计

基于国产FPGA芯片FMK50设计了一种多路高精度模拟信号源。设计由FPGA控制14位高精度DAC完成D/A转换,将产生的信号通过高速模拟开关及采样保持电路实现96路输出;采用内部ADC配合上位机设计自检模块对96路输出信号进行回采与标定。测试结果表明,系统在100%国产化的基础上稳定输出可配置的0～5 V电压信号且精度优于0.2%FS,自检模块设计大大提高了系统的输出精度及自动化程度。     

Critical Roles of Circular RNA in Tumor Metastasis via Acting as a Sponge of miRNA/isomiR

Circular RNAs (circRNAs), a class of new endogenous non-coding RNAs (ncRNAs), are closely related to the carcinogenic process and play a critical role in tumor metastasis. CircRNAs can lay the foundation for tumor metastasis via promoting tumor angiogenesis, make tumor cells gain the ability of migration and invasion by regulating epithelial-mesenchymal transition (EMT), interact with immune cells, cytokines, chemokines, and other non-cellular components in the tumor microenvironment, damage the normal immune function or escape the immunosuppressive network, and further promote cell survival and metastasis. Herein, based on the characteristics and biological functions of circRNA, we elaborated on the effect of circRNA via circRNA-associated competing endogenous RNA (ceRNA) network by acting as miRNA/isomiR sponges on tumor angiogenesis, cancer cell migration and invasion, and interaction with the tumor microenvironment (TME), then explored the potential interactions across different RNAs, and finally discussed the potential clinical value and application as a promising biomarker. These results provide a theoretical basis for the further application of metastasis-related circRNAs in cancer treatment. In summary, we briefly summarize the diverse roles of a circRNA-associated ceRNA network in cancer metastasis and the potential clinical application, especially the interaction of circRNA and miRNA/isomiR, which may complicate the RNA regulatory network and which will contribute to a novel insight into circRNA in the future.     

BOPP薄膜市场现状及发展趋势

介绍了我国双向拉伸聚丙烯薄膜的市场现状,并对其发展趋势进行了展望。