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The metastable polar orthorhombic phase is believed to be the origin of the ferroelectricity of hafnia-based films. The adjustment of stain, oxygen vacancies and dopant during film deposition and the wake-up electric cycling are common strategies to induce the ferroelectricity in hafnia. However, none of them could independently render the ferroelectric phase to be the most stable phase from the theoretical calculation results. The exact external conditions to stabilize orthorhombic phase still remain elusive. In this paper, we investigate the effects of the type, distribution, concentration, and charge state characteristics of oxygen vacancies and the uniaxial strain on the crystal' energy, dielectric constant and spontaneous polarization (Ps); In addition, the impact of the applied electric field parallel to the Ps on the crystal' energy is explored by first-principles calculations. It is challenging to independently stabilize the ferroelectric phase of hafnia-based films by a single component owing to the rather strict conditions. Surprisingly, the ferroelectricity can be easily obtained when simultaneously considering the effects of oxygen vacancies, uniaxial strain, and applied electric fields, suggesting the extremely important mechanical-electrical-chemical coupling effects. This work provides an explanation for the typical wake-up phenomenon in hafnia and a guidance for film applications. [ABSTRACT FROM AUTHOR]

The von Neumann bottleneck has long been a significant obstacle to the advancement of the era of intelligent computing. Neuromorphic devices are considered a promising solution to overcome this bottleneck. These devices draw inspiration from the information processing and computing capabilities of neurons in the human brain. Nevertheless, biomimetic synaptic devices used in neural network computing encounter significant challenges, including high nonlinearity in regulation, limited abundance of state conductance, and restrictions in unidirectional plasticity. Here, a memristor synaptic device is reported that utilizes the ion migration properties of MoTe2/MoS2−xOx heterojunction interface. This device demonstrates remarkable exceptional linearity, extensive dynamic regulation, and bidirectional independently controllable synaptic plasticity when subjected to bimodal regulation using electrical and optical signals. In addition, it shows significant paired‐pulse facilitation, empirical learning, and spike‐timing‐dependent properties. Furthermore, a deep learning framework is constructed to evaluate the reliability of devices in neuromorphic computation. The electronic synapses achieve high accuracy rates of 99.3% and 96.5% in recognizing digits and floral graphics, while photonic synapses achieve 95.3% and 91.5%. These findings emphasize the superior performance of photonic synapses in synaptic computation and provide a potential methodology for integrating multimodal neuromorphic hardware with artificial intelligence computing systems. [ABSTRACT FROM AUTHOR]

An amount of 100 dpa Si2+ irradiation was used to study the effect of transmutation rhenium content on irradiated microscopic defects and hardening in W-xRe (x = 0, 1, 3, 5 and 10 wt.%) alloys at 550 °C. The increase in Re content could significantly refine the grain in the W-xRe alloys, and no obvious surface topography change could be found after high-dose irradiation via the scanning electron microscope (SEM). The micro defects induced by high-dose irradiation in W and W-3Re alloys were observed using a transmission electron microscope (TEM). Dislocation loops with a size larger than 10 nm could be found in both W and W-3Re alloy, but the distribution of them was different. The distribution of the dislocation loops was more uniform in pure W, while they seemed to be clustered around some locations in W-3Re alloy. Voids (~2.4 nm) were observed in W-3Re alloy, while no void was investigated in W. High-dose irradiation induced obvious hardening with the hardening rate between 75% and 155% in all W-xRe alloys, but W-3Re alloy had the lowest hardening rate (75%). The main reasons might be related to the smallest grain size in W-3Re alloy, which suppressed the formation of defect clusters and induced smaller hardening than that in other samples. [ABSTRACT FROM AUTHOR]

In this paper, the impulsive multiple-bipartite consensus problem is discussed for networked second-order multi-agent systems (MASs) over directed network topology with acyclic partition. The definition of the multiple-bipartite consensus is introduced into second-order MASs by effectively combining the characteristics of bipartite consensus and group consensus based on the unique structure of network topology with acyclic and structural balance. By thoroughly exploring the coupling state between agents, a distributed impulsive multiple-bipartite consensus control protocol is designed for each agent by only measuring the relative information of its neighbors. Some sufficient conditions that guarantee realizing multiple-bipartite consensus are given, and the corresponding stability analysis is based on an improved Laplacian matrix associated with the network topology. Finally, some simulation examples are presented to verify the theoretical results. [ABSTRACT FROM AUTHOR]

Ferroelectric materials with the typical perovskite structure are widely used in capacitors, ultrasonic devices, oil drilling, transducers, and other fields. Lead-lanthanum-zirconium-titanate ceramics co-doped with Sn and Ba, have been widely investigated. However, there is little attention has been focused on the dielectric properties of barium-lanthanum-zirconium-titanate. Thus, in this work, Sn doped Ba0.955La0.03Zr0.02Ti0.98O3 ferroelectric ceramics were prepared via a classical high-temperature solid state reaction. Scanning Electron Microscopy (SEM) was used to observe the surface appearance of ceramics. The X-ray diffraction (XRD) patterns at room temperature, indicate that the ceramics are well crystallized. Impedance properties and dielectric properties reflect the characteristic of typical high temperature dielectric relaxation behavior. The conductive activation energy and the relaxation activation energy are obtained through the calculation of the Arrhenius law. The fitting results show that the dielectric relaxation behavior at high-temperature, was related to the oxygen defect. The electrical modulus verified the partial short-range carrier migration, also contribute to the high-temperature dielectric properties. [ABSTRACT FROM AUTHOR]

The Ba0.985La0.015Ti0.9Sn0.1O3 ceramic has been prepared by a cost-effective solid-state reaction method. Preliminary room-temperature X-ray diffraction indicates that the crystallization of the ceramic is good. Field Emission Scanning Electron Microscopy was used to study the microstructure of ceramic. X-ray photoelectron spectroscopy was used to characterize the oxygen vacancies. Dielectric properties and impedance spectroscopy reflected the characteristic of relaxor-type behavior. Modified Curie–Weiss law was used to evaluate the relaxor behavior. The fitting result of the relaxation parameter λ = 1.4, which verifies their relaxor property. Jonscher's power law was used to analyze the behavior of alternating current conductivity. The Arrhenius law was used to calculate the relaxor activation-energy (Ea) and the conduction activation-energy (Ec). The fitting results show that the Ea and Ec are 1.1 and 1. 13 eV, respectively. These values demonstrate that the high-temperature relaxor behavior was attributed to the double ionized oxygen vacancies. The electric field versus polarization curve reflects the energy-storage property of it. The maximum recoverable energy-storage density is 2.14 J/cm3, and the energy-storage efficiency is 67.65%. [ABSTRACT FROM AUTHOR]

The structural phase transitions for the hcp, bcc, dhcp, and fcc of magnesium at hydrostatic pressures larger than about 200 GPa at zero temperature are studied by first-principles total energy calculations. The plane-wave basis pseudopotential method has been adopted, in which the generalized gradient approximation implanted in the CASTEP code is employed. By comparing the enthalpy differences of the hcp structure with other three structures under different pressures, it can be seen that when the pressure becomes higher than about 65, 130, and 190 GPa, the bcc, dhcp, and fcc structures become more stable relative to the hcp structure, respectively. Due to the lowest enthalpy value of the bcc structure above 65 GPa, it can be deduced that magnesium may transform to the bcc structure from the ground state hcp structure around 65 GPa, but no further phase transitions occur without additionally applying high temperature. In addition, the equation of state of magnesium is calculated, indicating that bcc structure is the softest phase. [ABSTRACT FROM AUTHOR]

Key message: Overexpressing miR529a can enhance oxidative stress resistance by targeting OsSPL2 and OsSPL14 genes that can regulate the expression of their downstream SOD and POD related genes. Abstract: MicroRNAs are involved in the regulation of plant developmental and physiological processes, and their expression can be altered when plants suffered environment stresses, including salt, oxidative, drought and Cadmium. The expression of microRNA529 (miR529) can be induced under oxidative stress. However, its biological function under abiotic stress responses is still unclear. In this study, miR529a was overexpressed to investigate the function of miR529a under oxidative stress in rice. Our results demonstrated that the expression of miR529a can be induced by exogenous HO, and overexpressing miR529a can increase plant tolerance to high level of HO, resulting in increased seed germination rate, root tip cell viability, reduced leaf rolling rate and chlorophyll retention. The expression of oxidative stress responsive genes and the activities of superoxide dismutase (SOD) and peroxidase (POD) were increased in miR529a overexpression plant, which could help to reduce redundant reactive oxygen species (ROS). Furthermore, only OsSPL2 and OsSPL14 were targeted by miR529a in rice seedlings, repressing their expression in miR529aOE plants could lead to strengthen plant tolerance to oxidation stress. Our study provided the evidence that overexpression of miR529a could strengthen oxidation resistance, and its target genes OsSPL2 and OsSPL14 were responsible for oxidative tolerance, implied the manipulation of miR529a and its target genes regulation on HO related response genes could improve oxidative stress tolerance in rice. [ABSTRACT FROM AUTHOR]

Objectives The purpose of this study was to compare transvaginal 4-dimensional hysterosalpingo-contrast sonography with laparoscopic chromopertubation and evaluate the former's clinical value in assessing fallopian tubal patency and peritubal adhesion. Methods Fifty-six patients visiting infertility clinics were included in the study and underwent surgery by their own choice in 1 month. In total, 112 fallopian tubes were assessed. Twenty-five were primarily infertile, and the rest were secondarily infertile. Laparoscopic chromopertubation was taken as the reference standard. Results In a comparison of fallopian tubal patency between transvaginal hysterosalpingo-contrast sonography and laparoscopic chromopertubation, the sensitivity, specify, positive predictive value, and negative predictive value of hysterosalpingo-contrast sonography for diagnosing blocked fallopian tubes were 88.4%, 85.2%, 90.5%, and 82.1% respectively. In a comparison of spray at the fimbrial end between the no-peritubal adhesion and peritubal adhesion groups, the spray score at the fimbrial end in the no-peritubal adhesion group was significantly lower than that in the peritubal adhesion group. In a comparison of periovarian diffusion between the no-peritubal adhesion and peritubal adhesion groups, the periovarian diffusion score in the no-peritubal adhesion group was significantly lower than that in the peritubal adhesion group. In a comparison of periovarian diffusion between the patent-tube and blocked groups confirmed by chromopertubation, the periovarian diffusion score in the patent group was significantly lower than that in the blocked group. Conclusions Transvaginal hysterosalpingo-contrast sonography is a method with high sensitivity and specificity for screening fallopian tubal patency and peritubal adhesion. [ABSTRACT FROM AUTHOR]

In the spin-valve Co/Pt/[Co/Pt] multilayers with perpendicular magnetic anisotropy, it has been found that magnetoresistance, anomalous Hall resistivity, and longitudinal resistivity demonstrate oscillatory behaviors with the increase in Pt spacer thickness. Moreover, the parameter b oscillates as a function of Pt spacer thickness, which is experimentally determined by fitting the equation $\rho _{AH} =a^{\prime }\rho _{xx0} +b\rho _{xx}^{2} $ ( ρ is the residual resistivity, a is the skew scattering parameter, and b consists of the side jump and the intrinsic contributions) via the temperature dependence of the resistivity. These observed oscillatory behaviors can be mainly ascribed to the polarization of Pt spacer, while the polarization in the Co/Pt multilayers depends on the Pt spacer thickness. [ABSTRACT FROM AUTHOR]

The success of gene transfer has been demonstrated in many of vertebrate species, whereas the efficiency of producing transgenic animals remains pretty low due to the random integration of foreign genes into a recipient genome. The Sleeping Beauty (SB) transposon is able to improve the efficiency of gene transfer in zebrafish and mouse, but its activity in tilapia ( Oreochromis niloticus) has yet to be characterized. Herein, we demonstrate the potential of using the SB transposon system as an effective tool for gene transfer and insertional mutagenesis in tilapia. A transgenic construct pT2/tiHsp70-SB11 was generated by subcloning the promoter of tilapia heat shock protein 70 (tiHsp70) gene, the SB11 transposase gene and the carp β-actin gene polyadenylation signal into the second generation of SB transposon. Transgenic tilapia was produced by microinjection of this construct with in vitro synthesized capped SB11 mRNA. SB11 transposon was detected in 28.89 % of founders, 12.9 % of F1 and 43.75 % of F2. Analysis of genomic sequences flanking integrated transposons indicates that this transgenic tilapia line carries two copies of SB transposon, which landed into two different endogenous genes. Induced expression of SB11 gene after heat shock was detected using reverse transcription PCR in F2 transgenic individuals. In addition, the Cre/loxP system was introduced to delete the SB11 cassette for stabilization of gene interruption and bio-safety. These findings suggest that the SB transposon system is active and can be used for efficient gene transfer and insertional mutagenesis in tilapia. [ABSTRACT FROM AUTHOR]

We investigate the onset of chaotic phase synchronization of bursting oscillators in a modular neuronal network of small-world subnetworks. A transition to mutual phase synchronization takes place on the bursting time scale of coupled oscillators, while on the spiking time scale, they behave asynchronously. It is shown that this bursting synchronization transition can be induced not only by the variations of inter- and intra-coupling strengths but also by changing the probability of random links between different subnetworks. We also analyze the effect of external chaotic phase synchronization of bursting behavior in this clustered network by an external time-periodic signal applied to a single neuron. Simulation results demonstrate a frequency locking tongue in the driving parameter plane, where bursting synchronization is maintained, even with the external driving. The width of this synchronization region increases with the signal amplitude and the number of driven neurons but decreases rapidly with the network size. Considering that the synchronization of bursting neurons is thought to play a key role in some pathological conditions, the presented results could have important implications for the role of externally applied driving signal in controlling bursting activity in neuronal ensembles. [ABSTRACT FROM AUTHOR]

Carbon soot containing fullerene was continuously produced in volume by pyrolyzing acetylene in thermal HF-Plasma. The characteristics of the carbon soot and C60 were analyzed by thtransmission electron microscopy, UV/visible, IR and Raman spectroscopy. The results show that the main ingredients of the carbon soot with size of about 25 nm are amorphous carbon, graphite and fullerene. The fullerene yield in carbon soot is about 2.5 g·h−. Compared with the graphite arc discharge method, the acetylene thermal plasma method is a preferential one for synthesis of fullerene. [ABSTRACT FROM AUTHOR]

Microstructure and irradiation hardening of V-4Cr-4Ti alloys with different yttrium (Y) contents were studied by self-ion irradiation at 550 °C via TEM and nano-indentation test technology. The peak damage of the V-4Cr-4Ti-xY alloy (x = 0, 0.1, 0.5, and 1, wt.%) irradiated by 2.5 MeV self-ion (V2+) is 8 dpa. Dense dislocation loops were observed in all vanadium alloy samples after irradiation. With the increase of Y content, both average size and number density of dislocation loops using g = <110> near the pole [001] decreased, while the irradiation hardness increment first decreased and then increased. In order to better reduce the irradiation hardening, it is considered that the addition of 0.1 wt.% Y in V-4Cr-4Ti alloy is reasonable. [ABSTRACT FROM AUTHOR]