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Tin oxide is a promising channel material, offering the advantages of being low-cost and environmentally friendly and having a wide band gap. However, despite the high electron mobility of SnO2in bulk, the corresponding thin-film transistors (TFTs) generally exhibit moderate performance, hindering their widespread application. Herein, we proposed a codoping strategy to improve both the electrical property and the stability of SnO2TFTs. A comparative analysis between doped and undoped SnO2was conducted. It is observed that taking advantage of the difference in ionic radii between two dopants (indium and gallium) and the tin ions in the host lattice can effectively reduce impurity-induced strain. Additionally, we investigated the effect of codoping content on SnO2TFTs. The optimal codoped SnO2(TIGO) TFTs demonstrate high performance, featuring a field-effect mobility of 15.9 cm2/V·s, a threshold voltage of 0.2 V, a subthreshold swing of 0.5 V/decade, and an on-to-off current ratio of 2.2 × 107. Furthermore, the devices show high stability under both positive and negative bias stress conditions with a small threshold voltage shift of 1.8 and −1.2 V, respectively. Utilizing the TIGO TFTs, we successfully constructed a resistor-loaded unipolar inverter with a high gain of 10.76. This study highlights the potential of codoped SnO2TFTs for advanced applications in electronic devices.

Acinic cell carcinoma of the salivary gland (AciCC) is a low-grade carcinoma characterized by the overexpression of the transcription factor nuclear receptor subfamily 4 group A member 3 (NR4A3). AciCC has been the subject of a few molecular research projects. This study delves into AciCC’s molecular landscape to identify additional alterations and explore their clinical implications. RNA sequencing and immunohistochemical staining for markers NR4A3/NR4A2, DOG-1, S100, and mammaglobin were utilized on 41 AciCCs and 11 secretory carcinoma (SC) samples. NR4A3 was evident in 35 AciCCs, while the residual 6 were NR4A3-negative and NR4A2-positive; SC samples were consistently NR4A3-negative. A novel fusion, PON3exon 1–LCN1exon 5, was detected in 9/41 (21.9%) AciCCs, exhibiting a classical histologic pattern with serous cell components growing in solid sheets alongside the intercalated duct-like component. Clinical follow-up of 39 patients over a median of 59 months revealed diverse prognostic outcomes: 34 patients exhibited no disease evidence, whereas the remaining 5 experienced poorer prognosis, involving local recurrence, lymph node, and distant metastasis, and disease-associated death, 4 of which harbored the PON3::LCN1fusion. In addition, the HTN3::MSANTD3fusion was recurrently identified in 7/41 AciCC cases. SC patients lacked both fusions. Immunohistochemistry uncovered differential expression of DOG-1, S100, and mammaglobin across samples, providing nuanced insights into their roles in AciCC. This study accentuates PON3::LCN1and HTN3::MSANTD3fusions as recurrent molecular events in AciCC, offering potential diagnostic and prognostic utility and propelling further research into targeted therapeutic strategies.

The relationship between various patterns of mucin-producing salivary adenocarcinomas, including invasive salivary adenocarcinomas with mucinous differentiation, such as colloid and papillary carcinomas, remains unclear. Herein, we aimed to describe the clinicopathologic characteristics, immunophenotypes, molecular underpinnings, and clinical behavior of salivary mucinous adenocarcinomas (MA) to clarify their classification. We described a broad series of colloid and papillary patterns of MAs, indicating that papillary pattern presented papillary cystic proliferation of mucinous columnar cells as salivary intraductal papillary mucinous neoplasms with recurrent AKT1E17K mutations, whereas colloid adenocarcinomas containing large mucinous pools or lakes around the malignant epithelial nests or islands harbored BRAFV600E mutations with worse prognosis. Typical morphologic structures, CK7(+), CK20(–), CDX2(–), p63(–), p40(–), MAML2 fluorescence in situ hybridization (–), AR(–), TTF-1(–), S100(–), mammaglobin(–), or S100/mammaglobin(+) with ETV6 fluorescence in situ hybridization (–) immunophenotype, and recurrent AKT1E17K or BRAFV600E mutations may be defined. To our knowledge, this small series represents the first genetic study on a typical colloid pattern of MA, and our study with the spectrum documentation for MA in clinicopathologic characteristics, histologic and immunophenotypes, molecular features, and clinical behavior will allow for a better understanding of these rare but distinctive tumors.

In this work, particulate matter (PM) emissions from a large two-stroke, low-speed marine diesel engine were investigated when the engine was operated with low-sulfur heavy fuel oil (HFO) at various loads. Particle samples were collected in situ from the engine exhaust to determine the detailed physical and chemical properties. The nanostructure and morphology of the nanoparticles were analyzed using transmission electron microscopy images (TEM). The results show that volatile organic carbon (OC) accounts for more than 80% in the HFO particles and leads to an increase in particle size. The thermodynamic conditions of a low-speed engine favor the behavior of capturing the soluble organic components. A large number of spherical char HFO particles with aerodynamic diameters of 0.2 μm–0.5 μm and a suspected inner metal core were detected. The two peak aerodynamic diameters of the HFO nanoparticles are 15 nm and 86 nm. The morphological differences among the HFO nanoparticles in varied engine conditions represent the formation process from primary nascent particles to mature graphitized particles caused by thermodynamics. The above study will be valuable for understanding the characteristics of PM emissions from low-sulfur HFO to achieve the ship PM emissions reduction target.

A comprehensive understanding of the multifaceted ramifications of the coronavirus disease 2019 (COVID-19) on transit ridership is imperative for the optimization of judicious traffic management policies. The intricate influences of this pandemic exhibit a high degree of complexity, dynamically evolving across spatial and temporal dimensions. At present, a nuanced understanding remains elusive regarding whether disparate influencing factors govern inbound and outbound passenger flows. This study propels the discourse forward by introducing a methodological synthesis that integrates time series anomaly detection, impact inference, and spatiotemporal analysis. This amalgamation establishes an analytical framework instrumental in elucidating the spatiotemporal heterogeneity intrinsic to individual impact events, grounded in extensive time series data. The resulting framework facilitates a nuanced delineation, affording a more precise extraction of the COVID-19 impact on subway ridership. Empirical findings derived from the daily trip data of the Beijing subway in 2020 substantiate the existence of conspicuous spatiotemporal variability in the determinants influencing relative shifts in inbound and outbound ridership. Notably, stations situated in high-risk areas manifest a conspicuous absence of correlation with outbound trips, exhibiting a discernibly negative impact solely on inbound trips. Conversely, stations servicing residential and enterprise locales demonstrate resilience, evincing an absence of significant perturbation induced by the outbreak.

In this study, the aromatic carbon content of epoxy resin (EP) increased via carbon tar pitch (CTP) modification, and the CTP occurred self-polymerization reaction. The carboxyl and hydroxyl groups of CTP and the hydroxyl and carboxyl groups of EP occurred chemical cross-linking reaction. CTP and graphitization treatment promoted EP CF carbon crystal growth. The graphitization degree of pure EP CF and 40 wt% CTP modified EP CF are 8.42% and 44.21%, respectively. With the increase CTP content, the cell size, ligament junction and density of graphitization modified EP CF gradually increased, while the number of pores and cells gradually decreased. The cell size, ligament junction size and density of 40 wt% CTP modified graphitization EP CF increased to 1200 μm, 280 μm and 0.5033 g/cm3, respectively. EP CF exhibits entangling carbon ribbon and isotropic amorphous carbon. The 40 wt% CTP modified EP CF is composed of evenly distributed amorphous resin carbon and graphite domain CTP carbon. The graphitization modified EP CF improved electrical conductivity, and the electrical conductivity of 40 wt% CTP modified EP CF is 126.6 S/m. The compressive strength can be decided by EP carbon strength and its char yield, and graphitization 40 wt% CTP modified EP CF reached 4.9 MPa. This study provides some basis for preparation and application of CTP modified EP CF.

Macrophage-mediated inflammation plays an important role in hypertensive cardiac remodeling, whereas effective pharmacological treatments targeting cardiac inflammation remain unclear. Lipoprotein-associated phospholipase A2 (Lp-PLA2) contributes to vascular inflammation-related diseases by mediating macrophage migration and activation. Darapladib, the most advanced Lp-PLA2 inhibitor, has been evaluated in phase III trials in atherosclerosis patients. However, the role of darapladib in inhibiting hypertensive cardiac fibrosis remains unknown. Using a murine angiotensin II (Ang II) infusion-induced hypertension model, we found that Pla2g7(the gene of Lp-PLA2) was the only upregulated PLA2 gene detected in hypertensive cardiac tissue, and it was primarily localized in heart-infiltrating macrophages. As expected, darapladib significantly prevented Ang II-induced cardiac fibrosis, ventricular hypertrophy, and cardiac dysfunction, with potent abatement of macrophage infiltration and inflammatory response. RNA sequencing revealed that darapladib strongly downregulated the expression of genes and signaling pathways related to inflammation, extracellular matrix, and proliferation. Moreover, darapladib substantially reduced the Ang II infusion-induced expression of nucleotide-binding oligomerization domain-like receptor with pyrin domain 3 (NLRP3) and interleukin (IL)-1β and markedly attenuated caspase-1 activation in cardiac tissues. Furthermore, darapladib ameliorated Ang II-stimulated macrophage migration and IL-1β secretion in macrophages by blocking NLRP3 inflammasome activation. Darapladib also effectively blocked macrophage-mediated transformation of fibroblasts into myofibroblasts by inhibiting the activation of the NLRP3 inflammasome in macrophages. Overall, our study identifies a novel anti-inflammatory and anti-cardiac fibrosis role of darapladib in Lp-PLA2 inhibition, elucidating the protective effects of suppressing NLRP3 inflammasome activation. Lp-PLA2 inhibition by darapladib represents a novel therapeutic strategy for hypertensive cardiac damage treatment.

This article presents a novel silicon piezoresistor on polyimide (SPOP) technique for fabrication of differential pressure sensors (DPSs). Inspired by the bristled wing configuration of tiny wasps, a bristled polyimide (PI) cantilever was designed to detect the differential pressure caused by the aerodynamic loading on the surface of the cantilever. Compared with the conventional silicon-based DPS, the proposed DPS has a wide detection range, due to the large deformation of the flexible bristled cantilever and the enhanced leakage between the bristles. Boron-doped silicon was employed as the sensing material to improve the sensitivity of DPS. Experimental results indicate that the DPS has a high repeatability in the detection range of ±1000 Pa and exhibits sensitivity compression in high-pressure ranges. In addition, the sensitivity and resolution of the DPS are as high as $7.27\times 10^{-{5}}$ Pa $^{-{1}}$ and 0.32 Pa, respectively. Compared to other DPS, the cantilever-based SPOP-DPS exhibits a higher sensitivity in a wide detection range, resulting in promising applications.

The influence mechanism of tensile stress and tensile stress annealing on the strength and residual stress of the C19400 alloy is proved. The results show that after annealing at 100 °C under 35 MPa tensile stress, the tensile strength is 428.2 MPa, and the TD and RD residual stresses are −2 MPa and −8 MPa, respectively, which are 94.4% and 87.9% lower than that of the untreated state. This treatment can significantly reduce the residual stress of the C19400 alloy while maintaining its original tensile strength. The main factor affecting strength is the interaction between the precipitates and dislocations. Interestingly, the tensile stress has not no obvious relationship with the overall texture strength, but is positively related to the volume fraction of Brass texture. In addition, this study find that under the same level of dislocation density, no direct correlation exists between the magnitude of the residual stress and that of dislocation density. The ordered arrangement of dislocations is conducive to reducing the residual stress of the alloy. The results provide a reference for improving the performance of C19400 alloy.

The imbalance between the supply and demand of shared bikes is prominent in many urban rail transit stations, which urgently requires an efficient vehicle deployment strategy. In this paper, we propose an integrated model to optimize the deployment of shared bikes around urban rail transit stations, incorporating a seasonal autoregressive integrated moving average with long short-term memory (SARIMA-LSTM) hybrid model that is used to predict the heterogeneous demand for shared bikes in space and time. The shared bike deployment strategy was formulated based on the actual deployment process and under the principle of cost minimization involving labor and transportation. The model is applied using the big data of shared bikes in Xicheng District, Beijing. Results show that the SARIMA-LSTM hybrid model has great advantages in predicting the demand for shared bikes. The proposed allocation strategy provides a new way to solve the imbalance challenge between the supply and demand of shared bikes and contributes to the development of a sustainable transportation system.

Golden2 (G2), a member of the GARP transcription factor superfamily, regulates several biological processes and phytohormone signaling pathways in plants. In this study, we used a rice codon-optimized maize G2gene (rZmG2) to improve the regeneration efficiency of rice and maize calli for genetic transformation. We isolated a promoter driving strong and callus-specific expression from rice to drive rZmG2transcription from a transgene after transformation of two indicaand two japonicarice cultivars. The resulting rZmG2transgenic calli turned green in advance at the differentiation stage, thus significantly raising the regeneration rates of the transgenic indicaand japonicarice plants relative to control transformations. Similar effect of this gene on improving maize transformation was also observed. Transcriptome sequencing and RT-qPCR analyses showed that many rice genes related to chloroplast development and phytohormones are upregulated in rZmG2-transgenic calli. These results demonstrate that rZmG2 can promote embryogenic callus differentiation and improve regeneration efficiency by activating chloroplast development and phytohormone pathways. We also established a heat-inducible Cre/loxP-based gene-excision system to remove rZmG2and the antibiotic selectable gene after obtaining the transgenic plants. This study provides a useful tool for functional genomics work and biotechnology in plants.

A highly sensitive and specific detection of 2,4,6-trinitrotoluene (TNT), a typical nitrated aromatic explosive, was demonstrated by a silicon nanowire (SiNW) array sensor. The SiNW array devices were self-assembled and functionalized with the anti-TNT peptide to obtain unique sensitivity toward TNT. Also, the effect of the biointerfacing linker's chemistry and Debye screening with varied ionic strength of phosphate buffer solution (PBS) on TNT binding response signals were investigated. The optimization of the peptide-functionalized SiNW array sensor showed high sensitivity for TNT with a detection limit of 0.2 fM, the highest sensitivity reported to date. These initial promising results may help accelerate the development of portable sensors for femtomolar level TNT detection.

Graphical abstract:

Sound velocity errors often lead to distortion of seafloor topography in multibeam bathymetric data processing. The current method of sound velocity profile (SVP) inversion has the problems of small application scope of the inversed equivalent SVP (ESVP) and terrain distortion calculated by inversed SVP under the condition of water depth consistency constraint in overlapping line area. In this article, we propose a method of SVP inversion using the empirical orthogonal function (EOF) and differential evolution (DE) algorithm. First, EOF is used to decompose the SVP matrix. Then, the water depth discrepancy between the check line and the main survey line is used as the objective function instead of the discrepancy of overlapping line area, and DE is used to find the optimal time coefficient. Finally, the SVP is reconstructed to correct the seabed topography. The method was verified by experiments in shallow and mid-deep water, and the mean absolute and standard deviation of the corrected bathymetric discrepancy values are about 50% of those before correction.

Tuberculosis (TB), the second (after COVID-19) deadliest infectious killer, is a chronic infectious disease caused by infection with Mycobacterium tuberculosis(M.T.), where early diagnosis and management are the key to containing the condition. Here, we report a novel biosensor for the detection of M.T. DNA based on magnetic separation, urease catalysis and silicon nanowire field effect transistor (SiNW FET) detection. M.T. DNA is sequence-specifically captured by magnetic nanoparticles and urease-labelled silica nanoparticles simultaneously to form a sandwich complex and urea is catalyzed into ammonium carbonate by urease modified on a sandwich complex. By using SiNW FET, the detection of M.T. DNA is realized indirectly by the detection of ammonium carbonate. The limit of detection (LOD) was determined to be 78.541 fM. The specificity of the biosensor was confirmed by detecting a panel of bacterial species. The utility of the biosensor was demonstrated in real-sample analysis and the recovery study of M.T. DNA was done in the genomic DNA extracted from cultured Mycobacterium tuberculosis. The biosensor holds promise to become a rapid, sensitive and accurate method for clinical diagnosis.

In this article, a data-driven control strategy with prescribed performance is proposed to address the distributed bipartite consensus problem for unknown nonlinear multiagent systems (MASs) undersigned directed graphs. The dynamics of the agents in each topology are completely unknown and the desired trajectory information is only communicated to a subset of agents. First, the unknown nonlinear dynamic of each agent is transformed into an equivalent time-varying linearized model by utilizing the dynamic linearization method. Then, by considering the prescribed performance, a strictly increasing function is given to transform the constrained tracking error condition of the nonlinear MASs into an equivalent unconstrained error condition. Meanwhile, a new control protocol that only uses the input and output data of the agents is designed in the case of fixed or switched topologies. The proposed method can not only guarantee the bipartite consensus but also ensure the bipartite tracking error always converges to the prescribed region. Moreover, the designed control parameters can be adjusted appropriately to obtain better tracking performance. Finally, the convergence of bipartite consensus tracking error is guaranteed through rigorous theoretical analysis. The control scheme is further verified by two examples.

Diesel from direct coal liquefaction (DDCL) is a new type of engine alternative energy. But its hydrocarbon composition and physicochemical properties are quite different from those of Petro diesel. In this study, a premixed constant volume combustion chamber (CVCC) system with soot particle sampling devices was built. The soot particles in the spray flame were sampled and photographed by thermophoresis probe and transmission electron microscope (TEM). An automatic processing code based on Matlab software was developed to process the TEM images and extract the micro morphology parameters of the soot particles. This study has systematically studied the effects of sampling location, injection pressure, ambient density and oxygen concentration on the micro morphology of soot particles. The ambient density refers to the initial gas density in the CVCC. The results showed that various morphologies and sizes of soot particles coexisted in the upstream of the spray flame. During the evolution of soot particles from upstream to downstream in the flame, the size of soot aggregates gradually decreased, while the maturity of soot aggregates increased. With the increase of injection pressure, ambient density and oxygen concentration, the average sizes of soot aggregates and primary soot particles decreased, but the fractal dimensions of soot aggregates increased gradually. Under the same combustion condition and in-flame sampling location, the average projection area, gyration radius and primary soot diameter of soot aggregates produced by DDCL were significantly lower than those of Petro diesel. The structure of soot particles from DDCL was more compact than that of Petro diesel.

The steel turnout is one of the key components in the medium–low-speed maglev line system. However, the vehicle under active control is prone to vehicle–turnout coupled vibration, and thus, it is necessary to identify the vibration characteristics of this coupled system through field tests. To this end, dynamic performance tests were conducted on a vehicle–turnout coupled system in a medium–low-speed maglev test line. Firstly, the dynamic response data of the coupled system under various operating conditions were obtained. Then, the natural vibration characteristics of the turnout were analysed using the free attenuation method and the finite element method, indicating a good agreement between the simulation results and the measured results; the acceleration response characteristics of the coupled system were analysed in detail, and the ride quality of the vehicle was assessed by Sperling index. Finally, the frequency distribution characteristics of the coupled system were discussed. All these test results could provide references for model validation and optimized design of medium–low-speed maglev transport systems.

Tuberculosis (TB) remains a public health problem that cannot be ignored. The portable and efficient detection of Mycobacterium tuberculosis(MTB) is important for the effective control of this disease. However, current detection techniques do not meet the requirements for MTB detection in the actual environment and often require cumbersome detection steps that are time consuming and inflexible. In this study, a portable immunosensor to detect MTB in sputum was prepared and then subjected to interface characterizations, such as scanning electron microscopy, hydrophilic angle test, and fluorescence characterization. The source and gate voltage of the device were optimized and tested using a non-contact photoresponse. The results showed that the sensitivity of the sensor to luminance increases with the decrease in source voltage. The gate voltage can substantially improve the response of the immunosensor to the normalized current of protein and amplify the signal at least 1.6 times. The optimal voltage detection conditions of source voltage (0.3 V) and gate voltage (0.1 V) were also determined. Several common proteins present in simulated saliva were used for anti-interference tests, and the sensor exhibited good specificity. Finally, the dilution gradient of an actual TB sputum sample was optimized. In the absence of preconditioning, a double-blind experiment was used to distinguish between the sputum from patients with TB and healthy individuals to shorten the TB detection time to a few minutes. Compared with the hospital's conventional detection method using cultures, the proposed method can complete the detection in a shorter time. This study provides a new strategy for the portable diagnosis of TB.

Based on the high-resolution Mg/Ca and oxygen isotope ratio (δ18O) of planktonic foraminifera Globigerinoides ruber, sea surface temperature (SST) and salinity (SSS) were reconstructed in Core PC-1 from the northern Okinawa Trough during the last 24 kyr. From the last glacial maximum to Holocene, SST varied from 20.2°C to 24.6°C. Millennial-scale climatic events of the SST during the last glacial, such as the Heinrich events, Bølling-Allerød warming, and Younger Dryas, have been identified, which are synchronous with the climate changes in the North Atlantic, suggesting a teleconnection between the northwestern Pacific and the North Atlantic. During the last 24 kyr, the SSS variation can be divided into three parts: (1) during 21–15.5 ka, there was a significantly low SSS; (2) during 15.5–11.7 ka, the SSS increased obviously; (3) since 11.7 ka, the SSS is relatively stable. In order to discuss the main factors influencing the SSS in the northern Okinawa Trough, the relative abundance of Pulleniatina obliquiloculataand the oxygen isotope difference between the northern and middle Okinawa Trough (Δδ18Osw) have been used to indicate the intensity of the Kuroshio Current and Changjiang freshwater discharge, respectively. The Δδ18Oswresult shows that there is a large amount of Changjiang freshwater emptied into the northern Okinawa Trough during 18–15.5 ka, which is caused by the subtropical monsoon rain band lingering in the lower reaches of the Changjiang River drainage, supporting the Jet Transition Hypothesis. As the Kuroshio Current strengthened since 15.5 ka as indicated by the increased relative abundance of P. obliquiloculata, the variation of Kuroshio Current became the more important contribution to the SSS in the study region. The results of our study indicate that the key factor influencing the SSS in the northern Okinawa Trough is variable during the last 24 kyr.

Surface charges inside a nanopore determine the zeta potential and ion distributions and play a significant role in affecting ion transport and the sensitivity of detecting biomolecules. It is of great importance to study the fluctuation of surface charges with the salt concentration and pH in various applications of nanopores. Herein, we proposed a theoretical model to predict the surface charge density of a Si3N4nanopore, in which both silanol and amine groups were taken into account. It was demonstrated that the surface charge density in the Si3N4nanopore changes not only with pH but also with the salt concentration. The theoretical model could well predict the experimental results with different salt concentrations, pH values, and pore sizes. The effect of surface functional groups on the isopotential point (pHiep) of the Si3N4nanopore was also systematically studied. The results indicated that the silanol groups are major determinants of the surface charge, but the influences of the amine groups should not be ignored because the small number of amine groups can change pHiepdramatically. The pHiepvalue of the Si3N4nanopore was measured as 4.1, and the ratio of amine over silanol was ascertained as 0.013.

Chromatin undergoes extensive reprogramming during immune cell differentiation. Here we report the repression of controlled histone H3 amino terminus proteolytic cleavage (H3ΔN) during monocyte-to-macrophage development. This abundant histone mark in human peripheral blood monocytes is catalyzed by neutrophil serine proteases (NSPs) cathepsin G, neutrophil elastase and proteinase 3. NSPs are repressed as monocytes mature into macrophages. Integrative epigenomic analysis reveals widespread H3ΔN distribution across the genome in a monocytic cell line and primary monocytes, which becomes largely undetectable in fully differentiated macrophages. H3ΔN is enriched at permissive chromatin and actively transcribed genes. Simultaneous NSP depletion in monocytic cells results in H3ΔN loss and further increase in chromatin accessibility, which likely primes the chromatin for gene expression reprogramming. Importantly, H3ΔN is reduced in monocytes from patients with systemic juvenile idiopathic arthritis, an autoinflammatory disease with prominent macrophage involvement. Overall, we uncover an epigenetic mechanism that primes the chromatin to facilitate macrophage development.

ABSTRACTTrain-track-bridge dynamic tests were conducted on the Shanghai Lingang Medium and Low Speed Maglev Test Line. A newly developed levitation bogie with mid-set air spring was used on the test train. The test results show that: the vertical and lateral first-order natural frequencies are 7.50 Hz and 6.00 Hz, respectively; vehicle speed has no significant effect on the vertical dynamic displacement of the bridge; within specific speed ranges, the acceleration of the test train-track-bridge system shows monotonic variation characteristics as vehicle speed changes; the lateral accelerations of the bridge, sleeper, and F-shaped rail are distributed in a wider dominant frequency band compared with the corresponding vertical accelerations; the dominant frequency bands of vibration acceleration of levitation bogie and car body are generally concentrated below 15 Hz; the vertical and lateral Sperling indexes of the test train are less than 2.5, indicating that the test train is superior in ride quality.

This paper proposes an online data splicing power flow analysis method based on sensitivity analysis. Since the step-down transformer in the whole network data is usually equivalent to the 220 kV side, the equipment below 220 kV is not modeled in detail, and the provincial network data is modeled to 110kV and 35 kV voltage level equipment in detail. Different levels of modeling have a greater impact on the accuracy of stability analysis and calculation. Therefore, the purpose of improving data accuracy is achieved by splicing the entire network data (external network) and provincial network data (internal network). This paper is based on the sensitivity analysis method to stabilize the tie-line power by adjusting the output of the external network units, and form the whole network data that can accurately analyze the stability characteristics of the provincial network. The problem of power flow deviation caused by the voltage and angle deviation of the nodes at both ends of the regional tie line during the data splicing process is solved. Through the actual application of splicing the entire network and Hunan Provincial Network data, the effectiveness and necessity of the proposed method have been verified.

Electrically activated soft actuators capable of large deformation are powerful and broadly applicable in multiple fields. However, designing soft actuators that can withstand a high strain, provide a large actuation displacement, and exhibit stable reversibility are still the main challenges toward their practical application. Here, for the first time, we report a two-dimensional (2D) conductive metal–organic framework (MOF) based electrochemical actuator, which consists of vertically oriented and hierarchical Ni-CAT NWAs/CNF electrodes through the use of a facile one-step in situhydrothermal growth method. The soft actuator prepared in this study demonstrated improvements in actuation performance and benefits from both the intrinsically ordered porous architecture and efficient transfer pathways for fast ion and electron transport; furthermore, this actuator facilitated a considerably high diffusion rate and low interfacial resistance. In particular, the actuator demonstrated a rapid response (<19 s) at a 3 V DC input, large actuation displacement (12.1 mm), and a correspondingly high strain of 0.36% under a square-wave AC voltage of ±3 V. Specifically, the actuator achieved a broad-band frequency response (0.1–20 Hz) and long-term cyclability in air (10000 cycles) with a negligible degradation in actuation performance. Our work demonstrates new opportunities for bioinspired artificial actuators and overcomes current limitations in electrode materials for soft robotics and bionics.

In view of the lack of standard gauge for current medium-low speed maglev, the relationship between gauge and vehicle length, vehicle width and basic weight of maglev vehicle is studied in this paper. The effect of gauge increased from 1700 mm to 2000 mm on levitation capacity, anti-rolling capacity, device suspension space and F-rail magnetic-pole-face height difference for curve negotiation are analysed. The result indicates that the size of gauge is generally independent of vehicle length and is positively related to vehicle width and vehicle weight, but the reasonable internal design and layout can effectively control the vehicle weight. With gauge increased, the force of levitation electromagnet vertical force to balance the rolling moment, the rolling angle as well as the maximum vertical height difference between the inner and outer magnetic pole faces of F-rail all decreases. Overall, the vehicle levitation capacity and the anti-rolling ability are both improved. The maximum bending moment of sleeper is increased; and the lateral dimension of device suspension space of motor and longitudinal beam is increased.

Compressed Sensing Magnetic Resonance Imaging (CS-MRI) is an effective technique to reduce MRI data acquisition time. There is currently growing interest in using Alternating Direction Method of Multiplier (ADMM) for CS-MRI reconstruction. In this paper, we propose a flexible plug-and-play framework to incorporate the block matching 3D (BM3D) denoising algorithm as prior into the plug-and-play ADMM reconstruction procedure for CS-MRI reconstruction, termed BM3D Plug-and-play ADMM (BPA) method. We investigated the performance of the proposed BPA method for the construction of highly under-sampled MRI data of two different sampling masks. Compared with other widely used CS-MRI reconstruction methods, such as, PANO, BM3D-IT, BM3D-MRI and BM3D-AMP-MRI, the proposed framework can reconstruct highly under-sampled CS-MRI data with improved gains in Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index Measure (SSIM).

Abstract

Abnormal gas emission, coal and gas outburst may occur on the coal seam whose gas pressure and content are below catastrophe threshold, when the mine is deeply exploited. In order to study this catastrophe mechanism, solidfluid coupling experimental system with single degree of freedom and bidirectional loading is proposed. Gas percolation and catastrophe behaviour are studied through low pressure loading in this experiment, obtaining the following conclusions: 1) gas flow curve of gas-bearing coal shows asymmetric U shape; 2) coal sample suffers catastrophe gas emission after its rupture and instability under low pressure of 0.4 MPa and 0.15 MPa; 3) stress threshold of catastrophe gas-bearing coal sample is negatively related with coal gas pressure; 4) primary fracture of gas-bearing coal sample is consolidated when elastic deformation reaches 50% ~ 60% of elastic process, blocking gas percolation. However, gas percolation channel will be reopened after one yield or several yields. [Received: March 3, 2018; Accepted: November 18, 2018]

Heterostructured metal oxides with large specific surface area are crucial for constructing gas sensors with high performance. However, using slurry-coating and screen-printing methods to fabricate gas sensors cannot result in high uniformity and reproducibility of the sensors. Here, NiO nanowalls decorated by SnO2nanoneedles (NiO@SnO2) were in situ grown on ceramic microchips via a chemical bath deposition method to detect H2S instead of print-coating and slurry-coating methods. The morphologies and compositions of the NiO@SnO2hierarchical nanostructures (HNSs) were well tuned by varying the growth time of the NiO@SnO2HNSs to optimize the sensing performance. The response of the NiO@SnO2HNSs (2 h) to 1 ppm of H2S was over 23-fold higher than that of the pure NiO nanowalls and 17-fold higher than that of the pure SnO2nanosheets. This dramatic enhancement is attributed to the large surface area of the NiO@SnO2HNSs and the p–n heterojunction at the heterointerface of SnO2and NiO. The variation in the depletion layers (WSnO2and WNiO) at the heterointerface of SnO2and NiO greatly depends on the properties of the target gases (e.g., electron-withdrawing property (NO2) or electron-donating property (H2S)).