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Brain-inspired neuromorphic computing systems fueled the emergence of memristor-based artificial synapses, however, conventional silicon-based devices restricted their usage in the wearable field because of their difficulty in bending. To tackle the above challenge, a vertically structured flexible memristor with aluminum-based hydroquinone organic–inorganic hybrid film and Al2O3 as the functional layer, ITO and Pt as the bottom and top electrodes, and PET as the substrate has been developed utilizing molecular/atomic layer deposition to achieve a tradeoff between the resistive transition properties and the flexibility of memristors. The obtained devices combine stable resistive switching behavior and flexibility, showing high switching ratio of 103, better retention (up to 105 s) and endurance properties (up to 104 cycles), and robustness at radius of curvature of 4.5 mm after 104 bending cycles. Furthermore, the presence of multilevel resistive states in these devices ensures that the memristor can emulate synaptic properties such as paired-pulse facilitation, transition from short-term plasticity to long-term plasticity, long-term potentiation and depression, and spike-time-dependent plasticity. The resistive switching mechanism and the role of the bending state on the electrical performance of the device are explored. The fully connected artificial neural network based on the memristor can achieve a recognition accuracy of 90.2% for handwritten digits after training and learning. Flexible memristor will bring feasible advances to the integration of neuromorphic computing and wearable functionality. [ABSTRACT FROM AUTHOR]

After analyzing the main techniques to reduce the peak to average power ratio (PAPR),a partial transmission sequence method (CL-PTS) based on low correlation of chaotic sequences is proposed to solve the problem that the reduction effect is gene-rally not ideal.In this method,several chaotic sequences with low autocorrelation are multiplied by the original signal,and the average instantaneous power of OFDM system is reduced by inverse fast Fourier transform (IFFT).Simulation results show that when the complementary cumulative distribution function (CCDF) is 10－3,the PAPR reduction effect of this method is about 1 dB compared with other similar algorithms,but the algorithm is too complex and consumes more spectrum resources.On this basis,an improved correlation algorithm (CM-PTS) is proposed.This paper analyzes the influence of the number of sub blocks of PTS algorithm on the amount of computation and using the characteristics of IFFT transform,the PAPR can be reduced by changing the insertion position of the sequence in the system.The results show that CM-PTS algorithm can reduce the PAPR value by about 0.5 dB without increasing the BER.

Aiming at the degeneracy problem of discrete chaotic dynamics system in the digital domain, an algorithm that can configure the Lyapunov exponents of the system to be all positive is proposed.The algorithm is based on the principle of chaos anti-control.First, a feedback matrix is introduced.All the parameters in the set are specified carefully, and it is proved from a theore-tical point of view that the algorithm can configure the Lyapunov exponent to be fully positive.Subsequently, the boundedness of the system orbit and the finiteness of the Lyapunov exponent are proved, and the numerical simulation analysis and performance comparison of the configuration are carried out through several examples, so as to verify that the algorithm can produce a discrete chaotic system without degenerate.There are certain advantages in numerical accuracy and algorithm running time.The configured chaotic system is then used to generate the sequence and then quantized.The quantization scheme is to take out the effective digital combination of the sequence.Some dynamic transformation processing on the sequence can enhance the randomness and complexity of the output sequence.We convert the transformed output sequence into a binary sequence, perform a number of randomness and statistical tests, and compare the performance with the general chaotic sequence.The test results show that the sequence has better random characteristics and can be used in a chaotic sequence cipher system.

With the rapid development of electronics and communication technology,UAV (unmanned aerial vehicle) supported by these technologies have attracted the extensive attention of academia and industry.In order to adapt to the increasingly complex tasks and application fields,the UAV secure data link has become an important factor to promote the development of UAV.Focusing on the security issues of UAV data link,this paper discusses a series of advantages of OFDM (orthogonal frequency division multiplexing) technology,such as high spectrum utilization and anti-multipath-fading ability,and explains its application in UAV data link.Combining the long-term unpredictable characteristics of chaotic systems,a CSCM (chaotic sub-carrier modulation) scheme is proposed,which completes the chaotic serial-to-parallel conversion and chaotic disturbance on the data by using the quantized grouped chaotic sequence.This scheme realized the encrypted transmission of UAV data and the judgment on the reliability of the data source.Finally,MATLAB is used to simulate the scheme to verify the feasibility and effectiveness of the proposed scheme.

In the era of transcriptomics, the role of epigenetics in the study of cancers in females has gained increasing recognition. This article explores the impact of epigenetic modifications, such as DNA methylation, histone modification, and non-coding RNA, on cancers in females, including breast, cervical, and ovarian cancers (1). Our findings suggest that these epigenetic markers not only influence tumor onset, progression, and metastasis but also present novel targets for therapeutic intervention. Detailed analyses of DNA methylation patterns have revealed aberrant events in cancer cells, particularly promoter region hypermethylation, which may lead to silencing of tumor suppressor genes. Furthermore, we examined the complex roles of histone modifications and long non-coding RNAs in regulating the expression of cancer-related genes, thereby providing a scientific basis for developing targeted epigenetic therapies. Our research emphasizes the importance of understanding the functions and mechanisms of epigenetics in cancers in females to develop effective treatment strategies. Future therapeutic approaches may include drugs targeting specific epigenetic markers, which could not only improve therapeutic outcomes but also enhance patient survival and quality of life. Through these efforts, we aim to offer new perspectives and hope for the prevention, diagnosis, and treatment of cancers in females. [ABSTRACT FROM AUTHOR]

The inherent balance between dielectric constant and loss restricts the actual usage of dielectric elastomer actuators with high actuation strains, proposing a method that can break this trade‐off has been an urgent query. In this work, silica‐loaded carbon nanotubes (called SiO2@CNT) were prepared as dopants for acrylic resin elastomers (abbreviated as ARE) using the sol–gel method, and the obtained SiO2@CNT/ARE composites reached a dielectric constant of 282.5 at 100 Hz at a filler content of 3.22 vol%, which is 86 times higher than that of the pure ARE, whereas the dielectric loss remains at 0.17. The equilibrium between dielectric constant and loss is broken mainly based on the loading of SiO2 which inhibits the formation of carbon nanotube conductive network and concurrently reinforces the compatibility of the filler with ARE. Such a design offers a generalizable strategy for the subsequent preparation of polymer‐based composite films with excellent dielectric properties. Highlights: Preparation of fillers with excellent dispersibility in the organic phase.The ARE‐based composites exhibit excellent dielectric properties at 100 Hz.The mechanism of increase in dielectric constant is explained using two models. [ABSTRACT FROM AUTHOR]

Thermally conductive polymeric composites with low dielectric constant are highly promising for the packaging materials in the field of modern communication. Therefore, the synergistic improvement of low dielectric constant and high thermal conductivity has become a current research hotspot. In this work, we propose a one‐step alkylation of boron nitride nanosheet (BNNS) with ultrasonic stratification using 1‐hexanol, and then hot press the films to make Alkyl‐BNNSs orient in the fluorinated polyimide (f‐PI). The resulting Alkyl‐BNNS/f‐PI composite successfully realizes the synergistic improvement of thermal property and dielectric properties, exhibiting a high heat conductivity coefficient of 2.36 Wm−1 K−1 with a filler content of 4.99 wt.%. Moreover, the permittivity and dielectric loss of the film are as low as 1.76 and 0.0065 at 1 MHz, respectively. This work provides a facile strategy for breaking the bottleneck of making polyimide composites simultaneously with high thermal conduction and low dielectric performance. Highlights: The composite exhibits a high heat‐conducting coefficient of 2.36 Wm−1 K−1.Ultra‐low dielectric constant of 1.76 was achieved by the modification of film.Excellent breakdown resistance and flexibility were endowed with the composites. [ABSTRACT FROM AUTHOR]

Polyimide (PI) with excellent comprehensive properties has been extensively applied in electronic devices. The miniaturization and integration of electrical equipment put forward more stringent requirements for heat dissipation, so a composite with high thermal conductivity and low dielectric properties has become a critical factor. In this work, fluorinated graphene (FG) and boron nitride nanosheets modified with polydopamine (PDA@BNNS) were filled into the PI matrix as fillers to prepare FG/PDA@BNNS/PI composites. The mixed filling of FG and BNNS synergistically improves the dielectric and thermal conductivity, and this research breaks the balance barrier between dielectric and thermal conductivity. The resulting 4.99 wt % FG/PDA@BNNS/PI composite exhibited excellent comprehensive properties, including ultralow dielectric constant of 1.67, low loss of 0.013 at 1 MHz, and high thermal conductivity of 2.464 W m–1 K–1. In addition, the film also showed standout breakdown resistance (81.22 kV/mm) and mechanical properties such that the tensile strength reached 35.7 MPa. This report can inspire future development of composites for electronic packaging. [ABSTRACT FROM AUTHOR]

To overcome the effect of high actuation voltages causing dielectric elastomer films to breakdown, fabricating films with excellent dielectric properties and high durability is the current focus. Previously reported dielectric elastomer films, nevertheless, still require better dielectric properties and suffer from a lack of self-healing properties, which reduces the service life of the films. In this work, polysulfide polyurethane–urea (PSPU) elastomers with self-healing properties were synthesized through the insertion of dynamic disulfide bonds into the polymer chain segments via hydrogen transfer reactions. In addition, PSPU-based composites were fabricated in which the filler was MXene loaded with CeO2 obtained using a hydrothermal method. Benefiting from dynamic disulfide bonding and multiple hydrogen bonding interactions, PSPU attained a self-healing efficiency of 95%. Moreover, the 5.25 vol% CeO2@MXene/PSPU composite exhibited a dielectric constant of 206 at 100 Hz, maintaining a loss of 0.19 while having a self-healing efficiency of 97.9%. In contrast to PSPU, the dielectric constant of 5.25 vol% CeO2@MXene/PSPU was 34 times higher than that of the former at 100 Hz. These distinctive properties promise to render the films an integral part of the actuator. [ABSTRACT FROM AUTHOR]