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The western edge fault of the Maoyaba Basin, a branch of the Litang fault zone in western Sichuan, is the western boundary fault controlling the Great Maoyaba Basin. There have been no reports on its geometric distribution and deep structure. This article uses high-density electrical method and shallow seismic exploration technology to conduct geophysical exploration on the northern and southern sections of the western edge fault of the Maoyaba Basin, respectively. The response characteristics of the western edge fault of the Maoyaba Basin revealed by the high-density electrical method and shallow seismic exploration profiles are analyzed. The western edge fault of the Maoyaba Basin shows lateral displacement of the marker layer on the shallow seismic reflection profile, with the presence of fault diffraction waves and other phenomena. The tomographic inversion velocity profile reflects significant changes in the lateral velocity on both sides of the fault, suggesting that the depth of the upper breakpoint is shallower than 15 m. The low resistance strip characteristics on the apparent resistivity profile inverted by the high-density electrical method are preliminarily determined by combining field investigation and regional geological data to determine the production of the fault, shape, geometric structure, and planar layout. Advantages, disadvantages, and application prerequisites of the two geophysical methods in active fault detection are also explored in this article. Based on similar cases domestically and internationally, a combination of multiple methods is proposed to more effectively detect fault structures.

Abstract Backgroud Intrauterine Adhesions (IUA) is a common gynecological disease which is seriously endangers the reproductive function of women without any ideal treatment. Some researchers found Menstrual Blood-derived Mesenchymal Stem Cells (MenSCs) can repair of damaged endometrium, however, has not been fully clarified. This study aims to evaluate the therapeutic effects of MenSCs in IUA and the repair mechanism in vivo. Methods This study is Laboratory-based study. To evaluate the therapeutic effects of MenSCs in IUA, We cultivated MenSCs, established mouse endometrial injury model, observed the uterine morphology and degree of endometrial fibrosis and compared the expression of CXC chemokine ligand-13 (CXCL13)、CXC chemokine receptor-5 (CXCR5)、Plasmin Activating Inhibitor-1(Pai-1), Transforming Growth Faction-β1(TGF- β1) and Matrix Metalloproteinase-9 (Mmp-9) among each groups. GraphPad Prism 8.0 was used for statistical processing. Data were expressed as mean ± SD. Statistical comparisons among groups were performed with one-way ANOVA. P

Objective The prediction of abnormal formation pressure is a challenging issue in oil and gas development. With the continuous development of unconventional reservoirs such as shale gas and tight sandstone gas, the complexity of geopressure systems has increased. The coexistence of overpressure and underpressure in the same area often occurs, making it important to accurately characterize complex pressure systems. Methods In this work, two sets of overpressure systems and one set of underpressure systems formed in the Jurassic shale gas reservoir and tight sandstone reservoir in the Fuxing area were analysed. The geophysical responses and sensitive elastic parameters of overpressure and underpressure were analysed. The bulk modulus of the mudstone formation was strongly correlated with the formation pressure over the underpressure-overpressure interval. Based on this, an integrated prediction method for overpressure and underpressure based on the bulk modulus of mudstone was proposed and applied in this area by using well log and seismic data. The key of this method is to use the mudstone of overpressure and underpressure formations for integrated pressure prediction, reducing the influence of lithological changes. Second, the bulk modulus, which is directly related to the physical mechanism of abnormal pressure, was selected as the input parameter to improve the accuracy. Results According to the results of pressure prediction in the study area, the preservation conditions of the strong overpressure system in the Dongyuemiao Member are good, the pressure structure is stable, and the maximum pressure coefficient is approximately 2.0. The preservation conditions of the overpressure system in the Lianggaoshan Formation are relatively poor, with large lateral differences in pressure structure characteristics, and the maximum pressure coefficient is approximately 1.65; the pressure coefficient of the underpressure system in the Lianggaoshan Formation is approximately 0.5 to 1.0, and it has a certain coupling effect with the underlying overpressure system. Conclusion The predictions of overpressure and underpressure using well logs and seismic data in the study area both achieved high agreement with the measured data.

As the wind power generation becomes increasingly popular, the conventional inverter control methods may lead to power grid instability due to the reduction of inertia and susceptibility to parameter variations. In order to address this problem, a virtual synchronous generation (VSG) technology is combined with the quasi Z-source inverter (qZSI), which has the built-in boost function. To begin with, a finite switch sequence control strategy and an unconstrained optimization model predictive control (MPC) strategy are introduced to achieve multi-objective optimal control of the qZSI-VSG system. The average switching frequency of the inverter is reduced, the ability of the system to mitigate fluctuations in wind turbine output is enhanced, and the current harmonics are minimized. In addition, the computational complexity of the algorithm is simplified by eliminating the need for weight coefficients to be directly added to the cost function. Finally, the correctness and effectiveness of the proposed control strategy are verified by theoretical analysis and experimental results. Overall, this approach offers a promising solution to the challenges posed by the increasing integration of wind power into the power grid.

Abstract The physical mechanism of leader formation and development is not well understood. In this study, we present experimental and simulation results obtained with a 10 m long air gap discharge. A 10 m outdoor discharge experiment is carried out to obtain the current, voltage, and optical image during the leader discharge process. Four different impulse voltages were applied to the rod‐plane gap. The measured current is used as an input for a plasma model, then the temperature and electric field could be calculated. The simulation results show that the temperature of the streamer stem during the dark period may exceed 2000 K. In addition, the critical charge required for leader initiation can be as low as 0.27 μC for a 10 m air gap. The channel temperature is relatively stable in the process of leader development, which is maintained at about 4500 K. The electron density is about 0.5–3 × 1020 m−3, and the discharge channel conductivity fluctuates in the range of 1–10 S/m for the leader current between 1 and 2 A. A long dark period is tended to be associated with a higher injected charge by the first streamer. It is inferred that the voltage increments during the dark period play an important role in promoting streamer‐to‐leader transition, except for temperature and the injected charge.

Abstract Background Congenital antithrombin deficiency is an autosomal dominant disease that results in deep venous thrombosis and pulmonary embolism, which is mainly caused by mutations in the antithrombin gene (SERPINC1). Since SERPINC1 is highly susceptible to alterations, severe structural and functional changes that promote thrombosis may occur. Clinical presentations vary from different alterations. We report a pregnant case with novel mutation in SERPINC1 presenting transient antithrombin deficiency and multiple venous thromboembolisms. Case presentation We report a case of a 36-year-old pregnant patient who was diagnosed with congenital antithrombin deficiency for carrying a novel heterozygous mutation, NM_000488:exon5:c.T9 38 C:p. M313T in SERPINC1 presenting transient antithrombin deficiency and multiple venous thromboembolisms. Thrombolytic with alteplase and anticoagulant therapies with low-molecular-weight heparin and warfarin were administrated. After confirming the genetic analysis and the termination of pregnancy, rivaroxaban was administrated, and the thrombosis reduced. Conclusions Our study enriched the mutation database of SERPINC1 gene, provided some new theoretical basis for gene diagnosis and genetic counseling of patients with transient antithrombin deficiency. While it still needs for subsequent exploration of molecular pathogenesis.

This study aims to explore the role and regulatory mechanism of Yes-associated protein 1 (YAP1) in the development of Epstein-Barr virus-associated gastric cancer (EBVaGC). Here we showed that EBV can upregulate the expression and activity of YAP1 protein through its encoded latent products EBV-encoded small RNA 1 (EBER1) and latent membrane protein 2A (LMP2A), enhancing the malignant characteristics of EBVaGC cells. In addition, we also showed that overexpression of YAP1 induced the expression of EBV encoding latent and lytic phase genes and proteins in the epithelial cell line AGS-EBV infected with EBV, and increased the copy number of the EBV genome, while loss of YAP1 expression reduced the aforementioned indicators. Moreover, we found that YAP1 enhanced EBV lytic reactivation induced by two known activators, 12-O-tetradecanoylhorbol-13-acetate (TPA) and sodium butyrate (NaB). These results indicated a bidirectional regulatory mechanism between EBV and YAP1 proteins, providing new experimental evidence for further understanding the regulation of EBV infection patterns and carcinogenic mechanisms in gastric cancer.

Abstract A switching‐angle‐based hybrid modulation method of full wind speed and low carrier wave ratio for direct‐drive permanent‐magnet wind power generation system is proposed here, which order to improve the control performance of wind turbines in the full wind speed range. The combination manner of the proposed method is based on the harmonic distortion rate of the stator current, a modulation mode with a higher carrier wave ratio is adopted within the maximum switching frequency allowed by the system, the switching angle from optimized synchronous modulation also is introduced. In order to solve the problem of current impact caused by switching different modulation modes, the switching strategy between different modulation modes is developed from the perspective of harmonic current. And the sectors are redivided for the problem of sudden change in carrier wave ratio during switching, which improve the control effect of permanent‐magnet synchronous wind generator when changing the modulations modes. Finally, the feasibility and correctness of the proposed method are verified by theoretical analysis and simulation.

Abstract Aiming at the output current distortion problem in the low frequency operation of permanent magnet synchronous motor (PMSM) drive system of modular multilevel converter (MMC), the essential relationship between the output current distortion and the injected components is analyzed in this paper. A current harmonic suppression method combining feedforward and feedback compensation is proposed. Firstly, the feedback control method is applied to transform the MMC three‐phase output current into the dq rotating coordinate system at fundamental frequency ω. The harmonics of the AC terms to be suppressed are filtered out. The dominant fundamental frequency component turned into the DC term is retained. Then combined with feedforward control, the control performance of the system is improved. Secondly, the deadbeat predictive current control is improved by introducing an integral link in it. System disturbances caused by parameter changes can be compensated in real time. The design of the control system is simplified and the static error is reduced. Meanwhile, the system has the advantages of small torque pulsation and fast speed response. Finally, the PMSM drive system model of the 11‐level MMC is built in MATLAB/Simulink. The correctness and effectiveness of the proposed suppression method are verified.

Abstract As the core equipment of transmission and distribution hubs, the operational status of gas‐insulated switchgear (GIS) is closely linked to the safety of the power system. Recently, X‐ray digital imaging technology has been extensively used in GIS equipment fault detection. However, the X‐ray image of GIS is blurred, which is not conducive to the detection of tiny defects. Thus, a super‐resolution method for GIS X‐ray images based on multi‐scale context transformers is proposed in this study, namely MCTSR. Firstly, a second‐order image degradation model is introduced to generate GIS X‐ray low‐resolution images that more closely resemble the real world. Secondly, a contextual transformer gate module is constructed to improve attention to tiny defects in GIS X‐ray images. Thirdly, a U‐Net discriminator network based on multi‐scale contextual transformers is intended to enrich the information of the generated images. Finally, the proposed discriminator is combined with the existing generator to compose a super‐resolution method applicable to GIS X‐ray images. The experimental results demonstrate that the method outperforms other methods in peak signal‐to‐noise ratio and structural similarity on the constructed GIS X‐ray image dataset. In addition, the output image of the proposed method facilitates the subsequent defect detection.

Abstract Background The purpose of current retrospective study was to review the surgical methods and to evaluate the clinical efficacy of supporting plate for the treatment of vertical medial malleolus fractures on the basis of stable fixation of ipsilateral fibula. Methods This retrospective study included a total of 191 patients with vertical medial malleolus fractures. Patients enrolled were divided into simple vertical medial malleolus fractures and complex types of fractures. General demographic information and surgical information, including age, sex, surgical procedure and postoperative complications, were collected. The functional prognosis of patients was evaluated by American Orthopedic Foot and Ankle Society Ankle-Hindfoot Score (AOFAS) and Visual Analog Scale (VAS). Result Among patients with simple vertical fractures, the respective incidence of internal fixation failure in screw group, buttress plate group, and screw combined buttress plate fixation group (combined fixation group) was 10/61 (16.4%),1/54 (7.4%) and 1 (1.9%), and the difference was statistically significant (P = 0.024). The incidence of abnormal fracture growth and healing in screw group, buttress plate group and combined fixation group was, respectively, 13/61 (21.3%), 6/54 (12.5%) and 2 (3.85%), with statistically significant difference (P = 0.019). In the patients with complex types of fractures, after 2 years of postoperative follow-up, the AOFAS score and VAS score of the following subgroups had good results: 91.18 ± 6.05 and 2.18 ± 1.08 in patients with joint surface collapse, and 92.50 ± 4.80 and 2.50 ± 1.29 in patients with tibial fractures, with 100% excellent and good rate. Conclusion For simple and complex vertical medial malleolus fractures, buttress plate showed excellent fixation. Despite poor wound healing and extensive soft tissue dissection with this approach, buttress plate may provide a novel insight into medial malleolar fractures, especially for extremely unstable medial malleolar fractures.

Abstract Quasi‐Z source inverters (qZSI) can overcome the disadvantages of conventional wind power systems, because of achieving the balanced DC‐link voltage by using its boost ability. The majority of currently used control methods for conventional inverters are susceptible to parameter changes, and the qZSI are controlled by finite switching sequence model predictive control (FSS‐MPC). In this paper, a Variable weight coefficient Model Predictive Control (V‐MPC) strategy is proposed. First, based on the optimal scheduling algorithm, according to the priority of the controlled object. The proportioning weights of the global feasible solution and the local optimal solution in the algorithm are coordinated. Then, using the equality‐constraints quadratic programming method, according to the relationship between the system frequency and the reference value, increase the weight of the qZSI algorithm or increase the proportion of VSG control to improve the ability to suppress frequency fluctuations. It can give full play to the short‐term power support role of the virtual synchronous wind turbine. The modeling and testing findings validate the suggested control strategy. When compared to the conventional finite control set model predictive control (FCS‐MPC), the V‐MPC can minimize the big store inductance current ripple and have lower THD in the load currents waveform.

Abstract The SWISS rectifier is a three‐phase BUCK type Power Factor Correction rectifier with the advantages of adjustable output full voltage range, low voltage stress in the back stage devices, and high efficiency. However, because the voltage ripple of the input filter capacitor will cause the input current deviation, the input current of the SWISS rectifier will produce distortion at the sector boundary, which will affect the system performance. To this end, a multi‐stage predictive model method based on the spherical algorithm is presented. By predicting the grid‐side capacitor voltage and the input current state of the rectifier, the harmonic injection network switching tube is controlled in advance to supplement the grid‐side capacitor voltage, so that the grid‐side capacitor voltage approximately tracks the input voltage. Meanwhile, considering the current step that may be generated after the current distortion returns to normal, which leads to the resonance problem with the pre‐stage filter, this problem is incorporated into the value function and damping is optimized according to the feedback value. Finally, a 10‐kW SWISS rectifier on the SIMULINK platform is used to verify the feasibility of the new control method.

With the continuous deepening of ocean exploration, submersibles have become essential tools that have garnered considerable attention in the academia. As of the 2020s, driven by advancements in materials and various disciplines, the development of submersibles has undergone important transformations compared to their initial state. In this paper, we provide a comprehensive review of the developments in submersible technology from a historical point of view. In particular, we emphasize the emergence of the robotic fish-type submersibles. This process is characterized by the fusion of biomimicry and advanced technologies, and represents the future direction of submersible developments. Thus, we also emphasize the key technological challenges that robotic fish-type submersibles should focus on. Finally, we outline a general procedure for developing biomimetic robotic fish-type submersibles by drawing insights from a recent 2,000-m biomimicry prototype study. We hope to pave a smoother path for the future advancement of submersibles.

Southeast Tibet in China is rich in clean energy such as water energy, light energy, and wind energy. As the key means of large-scale clean energy transmission in southeast Tibet, the ultra-high voltage (UHV) power transmission projects will be constructed at an altitude of nearly 4000 m. To accurately acquire the external insulation strength of electrical equipment operating at different altitudes, the standard positive switching impulse voltages were applied to a rod electrode and a 1.1 m diameter shielding sphere at the altitude of 3400, 2100, and 80 m. The switching impulse discharge characterization and altitude correction factors of the 1.1 m diameter shielding sphere-plate gap under different clearances at different altitudes were obtained. The discharge voltage of the rod-plate gap at the altitude of 80 m was corrected to the altitude of 3400 m using altitude correction methods recommended by GB 311.1, GB/T 16927.1, and DL/T 2305. Further comparison was made between the calculation results using the three altitude correction methods mentioned above and the test results at an altitude of 3400 m. The discharge characterization and the minimum clearance of the end fittings of the electrical equipment in the valve hall at the altitude of 3800 and 4500 m were obtained by fitting and extrapolating the test data. The research results provide important reference significance for the external insulation configuration of UHV converter stations constructed in areas with an altitude of 3000 m and above.

Abstract To address the unsatisfactory performance of particle swarm optimization (PSO), a novel multi‐strategy self‐optimizing simulated annealing particle swarm optimization (SOSAPSO) method for permanent magnet synchronous motor (PMSM) parameter identification is proposed. The full‐rank mathematical model and the fitness function are developed. In SOSAPSO, the velocity term of the PSO is simplified and dynamic opposition‐based learning (DOBL) is introduced in the inertia weight update process to avoid population monotonicity. Moreover, A Cauchy–Gaussian hybrid variation strategy based on similarity and density is devised to achieve self‐learning in deep regions. Meanwhile, the simulated annealing (SA) with a memory and tempering mechanism is introduced into SOSAPSO, and the greedy optimization algorithm (GOA) is used to enhance local fine‐exploitation capabilities when SOSAPSO evolution is stalled. The test results indicate the proposed method can effectively avoid local convergence problems and has better robustness and convergence speed.

The main technical challenge of the medium-voltage Permanent Magnet Synchronous Motor (PMSM) drives with Modular Multilevel Converter (MMC) is the serious low-frequency fluctuation on the capacitor voltages. Therefore, a Hybrid Low Capacitance MMC (HLC-MMC) topology based on horizontal sub-module (SM) interconnection is proposed in this paper. Based on the three-phase symmetry of the input fluctuation currents of the sub-modules of the HLC-MMC, a fluctuation current coupling channel is established between the sub-modules with the same horizontal position of the three phases. The fluctuation currents are coupled and cancelled in the interconnection channel, and the amplitude of the fluctuation currents flowing into the sub-module capacitors is reduced. A switch tube in series with the DC bus is turned on and off at a regular frequency. The average DC voltage component in the bridge arm voltage is reduced and the voltage ripple of the capacitor is reduced. Then, a new control method is proposed for the HLC-MMC topology, where the energy is equalized between the upper and lower bridge arms of each stage by adjusting the fundamental frequency current components. The switching frequency of the series switches on the DC bus is controlled by duty cycle, and the measured average voltage of the control sub-module capacitors is equal to the reference voltage value. The overall energy of the system is balanced and the sub-module capacitor voltage ripple is further reduced. The correctness and effectiveness of the topology and the proposed control method are verified by simulation.

Through the analysis of logging, field outcrops, cores and geochemical data, and based on the study of the relationships between sea level changes, sequence filling, paleo-geomorphy and lithofacies, the sequence lithofacies paleo-geography and evolution process of the Lower Permian Liangshan-Qixia Formation (Qixia Stage for short) in Sichuan Basin and its surrounding areas are restored. The Qixia Stage can be divided into three third-order sequences, in which SQ0, SQ1 and SQ2 are developed in the depression area, and SQ1 and SQ2 are only developed in other areas. The paleo-geomorphy reflected by the thickness of each sequence indicates that before the deposition of the Qixia Stage in the Early Permian, the areas surrounding the Sichuan Basin are characterized by “four uplifts and four depressions”, namely, four paleo-uplifts/paleo-lands of Kangdian, Hannan, Shennongjia and Xuefeng Mountain, and four depressions of Chengdu-Mianyang, Kangdian front, Jiangkou and Yichang; while the interior of the basin is characterized by “secondary uplifts, secondary depressions and alternating convex-concave”. SQ2 is the main shoal forming period of the Qixia Formation, and the high-energy mound shoal facies mainly developed in the highs of sedimentary paleo-geomorphy and the relative slope break zones. The distribution of dolomitic reservoirs (dolomite, limy dolomite and dolomitic limestone) has a good correlation with the sedimentary geomorphic highs and slope break zones. The favorable mound-shoal and dolomitic reservoirs are distributed around depressions at platform-margin and along highs and around sags in the basin. It is pointed out that the platform-margin area in western Sichuan Basin is still the key area for exploration at present; while areas around Chengdu-Mianyang depression and Guangwang secondary depression inside the platform and areas around sags in central Sichuan-southern Sichuan are favorable exploration areas for dolomitic reservoirs of the Qixia Formation in the next step.

Federated ML (FL) provides an alternative to train accurate and generalizable ML models, by only sharing numerical model updates. Here, the authors present the largest FL study to-date to generate an automatic tumor boundary detector for glioblastoma.

In order to evaluate the ablation state of the SF6 circuit breaker contacts, simulated ablation tests were carried out on the circuit breaker, and the dynamic resistance curve as a function of contact travel was measured with three levels of injected current. The results showed that the increasing of test current value can reduce the fluctuation of the dynamic resistance curve as a function of contact travel. In addition to the ablation effect of current, the loosening of the operating mechanism will affect the accuracy of opening and closing action of the contact, resulting in the continuous reduction of the main contact travel in the dynamic resistance curve as a function of contact travel. Based on the measurement results, a BP neural network evaluation model was built to evaluate the ablation state of the contact. Seven parameters were extracted from the dynamic resistance curve as a function of contact travel as model inputs, and mean impact value algorithm was used to optimize the model. After the optimization, the average relative error of the evaluation to the verification set is less than 10.4%.

The anti-pollution flashover characteristic of composite insulators is the main indicators to evaluate their electrical performance, and the pollution flashover voltage can directly characterize the anti-pollution flashover characteristics of the insulators. This paper proposed an on-line detection method for the pollution flashover voltage of composite insulators. Samples of composite insulator shed with different hydrophobicity were prepared by using NaOH solution with pH value of 13 and temperature of 80 °C. According to the distribution of water droplets on the surface of the sample, the characteristic parameter of the number of water droplets was proposed. The samples with different characteristic parameters were smear-stained and used for the pollution flashover voltage test. The relationships between the number of water droplets on the sample surface and the pollution flashover voltage and leakage current were obtained, which can provide guidance for the evaluation of the operation state of composite insulators.

Abstract This paper aims at the problems of the traditional modular model predictive control (MPC) of modular multilevel converter (MMC) with huge computational complexity and high equivalent switching frequency. In this paper, a model predictive control method based on fixed switch state set (FSS‐MPC) is proposed. In this method, two cost functions are used to control phase current and circulating current. Meanwhile, the number of the upper and lower on‐state sub‐modules (SM) is obtained by cost functions. In order to obtain the optimal switching sequence of SM, FSS‐MPC adopts a SM capacitive voltage balancing strategy which has low sorting frequency. Under the control of the FSS‐MPC, the amount of switch combination and sorting computation are greatly reduced. In addition, the switching frequency is extremely low. Finally, to verify the effectiveness and feasibility of the proposed control strategy, a simulation system of 11‐level MMC for offshore wind power has built on the MATLAB/Simulink platform.

The evaluation of post-mature source rocks gradually invalidates by traditional organic geochemical parameters due to the decreasing of organic matter abundance. However, the inorganic elements in source rocks are not easily affected by thermal evolution. In order to explore the application of inorganic geochemical methods in the evaluation of post-mature source rocks, this paper takes the Sinian-Cambrian source rocks in the Sichuan Basin as an example to conduct an evaluation based on the inorganic (major, trace and rare earth elements) geochemistry method with three controlling factors of source rock development (paleoproductivity, sedimentary environment and sedimentary rate). The concentration of Ba and Ni, MoEF and UEF and Ce anomaly, and TiO2/Al2O3 ratio could be correlated with paleoproducitvity, sedimentary environment and sedimentary rate, respectively. The results showed that the enrichment of organic matter was mainly controlled by sedimentary environment and paleoproductivity, but are barely effected by sedimentary rate. Source rocks in the Lower Cambrian Qiongzhusi Formation in the central Sichuan and Weiyuan-Ziyang areas have high paleoproductivity and the most reduced environment and thus are one of the best quality source rocks. Therefore, inorganic geochemistry method is an effective way to evaluate postmature source rocks.

The cutting part planet carrier is the key part of the shearer，and its time-varying reliability has an important influence on the comprehensive performance of shearer. Rigid-flexible coupling model of shearer with planetary carrier as modal neutral file is established based on Pro/E，and weak areas and dynamic stress of the cutting part planet carrier are obtained by studying the dynamics performance of the planetary carrier. The probability density function of the three-parameter Weibull distribution in the weak region of the cutting part's planet carrier is obtained by Matlab and the rationality of its fitting is verified with Kstest function. According to the fatigue life reliability theory，the fatigue life reliability model of planetary carrier is established. By calculation，the time-varying reliability of multiple weak areas of planetary carrier based on Copula function is to degrade exponentially from 0.936 2 until the failure of the planetary carrier. Combined with reliability sensitivity design theory，the influence of multiple weak areas design variables on the time-varying reliability of the cutting part planet carrier is analyzed. This provides theoretical basis and accurate data support for related research on the planet carrier.

ABSTRACT Epstein-Barr virus-associated gastric carcinoma (EBVaGC) is one of the four subtypes of gastric carcinoma and its unique clinicopathological mechanism is unclear. Herein, the expression of endothelin-1 (ET-1) in EBVaGC was lower than of Epstein-Barr virus-negative gastric carcinoma (EBVnGC) and associated with a low frequency of lymph node metastasis of EBVaGC. Functional studies showed that the activation of ET-1/endothelin receptor type A (ETAR) axis could promote cell growth, migration, and antiapoptosis. The expression of the ET-1 gene was unrelated to methylation of its promoter region and miRNAs (-1, -125a, -125b). After being treated with MEK1/2 inhibitor (PD0325901), the inactivation of ERK1/2 pathway resulted in downregulation of ET-1 and forkhead box O1 (FOXO1) expression. Further, FOXO1 knockdown decreased the ET-1 expression. These findings indicated that ET-1 could be involved in development of gastric cancer and EBV could suppress the expression of ET-1 via the regulation of the transcription factor FOXO1 through the MAPK/ERK pathway. IMPORTANCE The relationship between Epstein-Barr virus and gastric cancer has been relatively clear. However, there are still many unresolved mechanisms of the virus in tumorigenesis. In recent years, activation of the endothelin-1 signaling axis has been found to play an important role in tumorigenesis, which is involved in tumor angiogenesis and epithelial-mesenchymal transition. EBV genes. In our study, we found that ET-1 was low-expressed in EBV-positive gastric cancer cells, which was due to the inhibition of ERK signaling by EBNA1 through the repression of FOXO1 expression. The low expression of ET-1 limits the proliferation, migration, and anti-apoptotic ability of tumor cells. These findings contribute to further understanding of the role of EBV in EBV-associated gastric cancer.

Abstract: In view of the problems of large volume, high energy consumption and difficult maintenance of electric field measurement sensors in existing power systems, non-contact miniature electric field sensors have become a hot topic in current research. In this paper, a MEMS miniature electric field measurement sensor model based on the principle of piezoelectric-piezoresistive coupling is constructed, and the sensor structure is optimized by analyzing the steady-state characteristics of the piezoelectric material and semiconductor membrane of the sensor. The input and output characteristics of the sensor were tested. The test results show that the sensor has excellent mechanical strain capacity, and the output voltage of the sensor has a linear relationship with the electric field strength, thus verifying the feasibility of the sensor measurement in the electric field. The research results will provide some reference for the development of contactless coupled sensors.

Abstract To comprehensively reuse copper ore tailings (COT), the fabrication of glass‐ceramics by the direct sintering method was investigated, where the residues after sulfur release and iron recovery from copper ore tailings were used as raw materials. The effect of the CaO added on the fabrication of glass‐ceramics was emphasized. After analysis of chemical composition and thermodynamics, crystallization kinetics were analyzed by Differential Scanning Calorimetry (DSC) and fitted to the Kissinger equation. The crystal phase and microstructure of sintered glass‐ceramics heated between 1080 °C and 1100 °C were estimated by X‐Ray diffraction analysis (XRD) and Scanning Electron Microscopy (SEM), respectively. Furthermore, the effects of the addition of CaO on the properties of the sintered glass‐ceramics have been discussed. The results showed that the magnetic glass‐ceramics were sintered by the residues successfully, the color of which was lighter than that of glass‐ceramics sintered by raw materials before iron recovery. According to the XRD analysis, hedenbergite, wollastonite and sekaninaite were formed with traces of maghemite and quartz. In terms of crystallization kinetics and sintering results, a decrease in the activation energies of crystallization and in sintering temperature were observed for an increase in the addition of CaO of up to 10 wt.%. Moreover, the properties of the sintered glass‐ceramics, including bulk density, linear shrinkage and flexural strength, were enhanced, while water absorption and true density were reduced with the increase of the amount of CaO added.

Abstract Background Osteoarthritis (OA) is the most prevalent chronic joint disease, and is hard to be cured at present. Cytokine receptor-like factor 1 (CRLF1) has been identified as an upregulated gene in OA cartilage. However, the precise identities and functions of CRLF1 in OA progression have remained to be fully elucidated. Methods We used a murine model of injury-induced OA (destabilization of medial meniscus, DMM) and BMSCs to investigate the specific biological functions and mechanisms of CRLF1. Results We found that CRLF1 was significantly increased in the DMM surgery-induced OA model and was down-regulated during chondrogenic differentiation of BMSCs. Luciferase reporter assays showed that CRLF1 was a direct target of miR-320 in BMSCs. miR-320 can reverse the effect of CRLF1 on cell proliferation, apoptosis and chondrogenic differentiation of BMSCs. Furthermore, knockdown of CRLF1 or over-expression of miR-320 can inhibit the apoptosis of primary chondrocytes. Conclusion Suppression of CRLF1 promotes the chondrogenic differentiation of BMSCs and protects cartilage tissue from damage in osteoarthritis via activation of miR-320.

BackgroundThough immunotherapy has become one of the standard therapies for colon cancer, the overall effective rate of immunotherapy is very low. Constructing an immune-related genes prognostic index (IRGPI) model may help to predict the response to immunotherapy and clinical outcomes.MethodsDifferentially expressed immune-related genes (DEIRGs) between normal tissues and colon cancer tissues were identified and used to construct the co-expression network. Genes in the module with the most significant differences were further analyzed. Independent prognostic immune-related genes (IRGs) were identified by univariate and multivariate cox regression analysis. Independent prognostic IRGs were used to construct the IRGPI model using the multivariate cox proportional hazards regression model, and the IRGPI model was validated by independent dataset. ROC curves were plotted and AUCs were calculated to estimate the predictive power of the IRGPI model to prognosis. Gene set enrichment analysis (GSEA) was performed to screen the enriched KEGG pathways in the high-risk and low-risk phenotype. Correlations between IRGPI and clinical characteristic, immune checkpoint expression, TMB, immune cell infiltration, immune function, immune dysfunction, immune exclusion, immune subtype were analyzed.ResultsTotally 680 DEIRGs were identified. Three independent IRGs,NR5A2, PPARGC1A and LGALS4, were independently related to survival. NR5A2, PPARGC1A and LGALS4 were used to establish the IRGPI model. Survival analysis showed that patients with high-risk showed worse survival than patients in the low-risk group. The AUC of the IRGPI model for 1-year, 3-year and 5-year were 0.584, 0.608 and 0.697, respectively. Univariate analysis and multivariate cox regression analysis indicated that IRGPI were independent prognostic factors for survival. Stratified survival analysis showed that patients with IRGPI low-risk and low TMB had the best survival, which suggested that combination of TMB and IRGPI can better predict clinical outcome. Immune cell infiltration, immune function, immune checkpoint expression and immune exclusion were different between IRGPI high-risk and low-risk patients.ConclusionAn immune-related genes prognostic index (IRGPI) was constructed and validated in the current study and the IRGPI maybe a potential biomarker for evaluating response to immunotherapy and clinical outcome for colon cancer patients.

Knowledge graphs (KGs) serve as a crucial resource for numerous artificial intelligence tasks, significantly contributing to the advancement of the AI field. However, the incompleteness of existing KGs hinders their effectiveness in practical applications. Consequently, researchers have proposed the task of KG completion. Currently, embedding-based techniques dominate the field as they leverage the structural information within KGs to infer and complete missing parts. Nonetheless, these methods exhibit limitations. They are limited by the quality and quantity of structural information and are unable to handle the missing entities in the original KG. To overcome these challenges, researchers have attempted to integrate pretrained language models and textual data to perform KG completion. This approach utilizes the definition statements and description text of entities within KGs. The goal is to compensate for the latent connections that are difficult for traditional methods to obtain. However, text-based methods still lag behind embedding-based models in terms of performance. Our analysis reveals that the critical issue lies in the selection process of negative samples. In order to enhance the performance of the text-based methods, various types of negative sampling methods are employed in this study. We introduced prompt learning to fill the gap between the pre-training language model and the knowledge graph completion task, and to improve the model reasoning level. Simultaneously, a ranking strategy based on KG structural information is proposed to utilize KG structured data to assist reasoning. The experiment results demonstrate that our model exhibits strong competitiveness and outstanding inference speed. By fully exploiting the internal structural information of KGs and external relevant descriptive text resources, we successfully elevate the performance levels of KG completion tasks across various metrics.

In the design and manufacturing of epoxy resin insulation components, complex structures can be achieved through multiple pours, thereby forming the structure of interface of laminated epoxy resin. This type of interface structure is often considered a weak link in performance which can easily accumulate charges and cause electric field distortion. However, research on the interlayer interface of epoxy resin has received little attention. In this study, epoxy samples with and without interlayer interfaces were prepared, and the space charge accumulation characteristics and trap characteristics of the samples were analyzed via pulsed electro-acoustic (PEA) and thermally stimulated depolarization current (TSDC) methods. The experimental results indicate that the Maxwell–Wagner interface polarization model cannot fully explain the charge accumulation at the interface. Due to the influence of the secondary curing, the functional groups in the post-curing epoxy resin can move and react with the partially reacted functional groups in the prefabricated epoxy resin layer, resulting in a weak cross-linking network at the interface. With the increase in temperature, the molecular chain segments in the weak cross-linked region of the interface become more active and introduce deep traps at the interface, thereby exacerbating the accumulation of interface charges. In addition, due to the influence of interface polarization and weak cross-linking, the ability of the interface charges to cause field strength distortions decreases with the increase in applied field strength. This research study can provide a theoretical reference for the interfacial space charge transport characteristics of epoxy-cured cross-linked layers and provide ideas for regulating interfacial cross-linking to suppress interfacial charge accumulation.

The marine facies highly mature natural gas system with the Lower Cambrian Qiongzhusi Formation as the source rock in the Sichuan Basin is a global model in this field. To deepen the geological understanding of high quality source rocks and the natural gas exploration areas in the Sichuan Basin, taking two hot exploration blocks in the central and northeastern parts of Sichuan Basin as examples, the differential mechanisms of organic matter accumulation in source rocks of the Qiongzhusi Formation were studied, and some gas exploration areas were identified by the means of geochemical methods from three perspectives, including paleoproductivity, redox conditions and input of terristral organic matters. The TOC of source rocks within deep-water shelf in the intracratonic rift sampled from the Gaoshi 17 and Zhongjiang 2 wells in the central Sichuan were higher than that of source rocks within the shallow-water shelf sampled from the Xiaoyangba outcrop, northeastern Sichuan. The organic matter accumulations of both sample sets were mainly controlled by redox condition, but in comparison, the source rocks in the central Sichuan Basin were formed in relative anoxic environment, which was more conducive for the preservation of organic matter than the suboxic environment in northeastern Sichuan Basin. In addition, the dilution effection by terrestrial organic matter input was particularly significant during the formation of source rocks in the northeastern Sichuan Basin, leading to poorer source rock quality. The exploration of natural gas system in the Qiongzhusi Formation still needs to be carried out closely around the intracratonic rift and its surrounding margin in the future, and the deep-water shelf area around the basin also deserves attention. Both conventional and unconventional natural gas resources should be considered.

Based on outcrop, drilling, logging, geochemical analysis and seismic data, the karst landform and distribution of Permian volcanic rocks at the end of the sedimentary period of the Maokou Formation in the western Sichuan Basin are examined, and their petroleum geological significance is discussed. Affected by normal faults formed in the early magmatic activities and extension tectonic background in the late sedimentary period of the Maokou Formation, a local karst shallow depression under the background of karst slope came up in the Jianyang area of the western Sichuan Basin, where the residual thickness of the Maokou Formation was thinner. Basic volcanic rocks like pyroclastic rock of eruptive facies, basalt of overflow facies, diabase porphyrite of intrusive facies and sedimentary tuff of volcanic sedimentary facies were formed after karstification. However, under the effects of faulting and karst paleogeomorphology, the volcanic rocks in different areas had different accumulation features. In the Jianyang area, with long eruption time, the volcanic rocks were thick and complex in lithology, and accumulated in the karst depressions. In the Zhongjiang-Santai area located in the karst slope, there’s no fault developed, only thin layers of basalt and sedimentary tuff turned up. The karst landform controls the build-up of thick explosive facies volcanic rocks and also the development of karst reservoirs in the Maokou Formation, and the western Sichuan area has oil and gas exploration potential in volcanic rocks and the Maokou Formation.

ABSTRACT Epstein-Barr virus (EBV), a ubiquitous oncogenic herpesvirus, infects more than 90% of the adult population worldwide. The long noncoding RNA H19 is downregulated in EBV-positive gastric cancer (EBVaGC) and nasopharyngeal cancer (NPC). In this study, we found that loss of H19 is caused by hypermethylation status of the H19 promoter in EBV-positive GC and NPC cell lines. Furthermore, latent membrane protein 1 (LMP1), encoded by EBV, induced H19 promoter hypermethylation and deregulated the expression of H19 by upregulating DNMT1 expression. Transwell assays showed that H19 promoted cell migration. Furthermore, H19 promoted cell proliferation and inhibited apoptosis in CCK-8 and flow cytometry assays, respectively. p53, a well-known tumor suppressor, was upregulated in EBVaGC and NPC cell lines. miR-675-5p derived from H19 inhibited p53 protein expression by targeting the 3′ untranslated region of the gene. Overall, we found that LMP1 induced p53 protein expression via the H19/miR-675-5p axis in EBVaGC and NPC. LMP1 induced H19 promoter hypermethylation, which repressed the expression of H19 and miR-675-5p and caused p53 protein overexpression in EBVaGC and NPC cells. IMPORTANCE Epstein-Barr virus (EBV) is the first virus to be known to have direct association with human cancer and to be considered as an important DNA tumor virus. The EBV life cycle consists of both latent and lytic modes of infection in B lymphocytes and epithelial cells. The persistence of EBV genomes in malignant cells promoted cell growth. p53, acting as a critical gatekeeper tumor suppressor, is involved in multiple virus-mediated tumorigeneses. Overexpression of p53 inhibits the ability of BZLF1 (EBV-encoded immediate early gene) to disrupt viral latency. In our study, we found LMP1 induces H19 promoter hypermethylation, which represses the expression of H19 and miR-675-5p and results in p53 protein overexpression in EBVaGC and NPC cells. These observations suggest a new mechanism of aberrant expression of p53 by LMP1, which facilitates EBV latency.

Based on drilling data of JT1 and CS1, outcrop profiles and seismic data, the sedimentary pattern, space configuration of source-reservoir-cap combinations and paleouplift evolution characteristics of the Cambrian Lower Canglangpu Member in the central Sichuan paleouplift have been investigated to determine the favorable exploration zones. Controlled by Deyang-Anyue rift, the Lower Canglangpu Member features differential characteristics from east to west in sedimentary framework. In the west side of the Deyang-Anyue rift, this member is composed of clastic sediments, while in the east side of the Deyang-Anyue rift, it is fresh water shelf sediments, with grain beaches occurring along edges of the depressions, shelf and lagoon. Among the beaches, the dolomitic ones are mainly distributed around the depression edge and in the north of the lagoon. The beach sediments could become high quality reservoirs under the effect of karstification. Underlying the Lower Canglangpu Member is the widespread source rock of the Qiongzhusi Formation, so oil and gas generated by the Qiongzhusi Formation source rock can directly charge into the beach reservoirs. The sandy mudstone of the Upper Canglangpu Member can serve as the caprock of the Lower Canglangpu Member reservoir. The dolomitic beaches are located at the higher part of the paleo-uplift during the main accumulation period, with good hydrocarbon accumulation elements. Blocks PT1-CS1, HT1-GT2 and east GT2 are favorable exploration zones.

Based on analysis of outcrop, drilling, logging and seismic data, and geotectonic background, the lithofacies paleogeography and paleokarst geomorphology of the Middle Permian Maokou Formation in the northwestern Sichuan Basin were reconstructed, and the petroleum geological significance of the lithofacies paleogeography and paleokarst geomorphology were discussed. The Maokou Formation is divided into 3 long-term cycles, namely LSC1, LSC2 and LSC3, which correspond to the Member 1, Member 2 and Member 3 of the Maokou Formation, respectively. Controlled by the extensional structure caused by opening of the Mianlue Ocean in the north margin of the upper Yangtze blocks and basement faults produced by mantle plume uplifting, the area had tectonic differentiation in NWW and NE, and sedimentary basement took on episodic settlement from north to south, as a result, the sedimentary systems of Member 1 to Member 3 gradually evolved from carbonate platform to platform-slope-continental shelf. According to the residual thickness, paleokarst geomorphologic units such as karst highland, karst slope and karst depression at different stages were reconstructed. The karst geomorphological units were developed successively on the basis of sedimentary geomorphology. Sedimentary facies and paleokarst geomorphology are of great significance for oil and gas accumulation. The Maokou Formation in northwestern Sichuan has two kinds of most favorable reservoir zone combinations: high energy grain shoal and karst monadnock, platform margin slope and karst slope. Based on this understanding, the planar distribution of the two kinds of reservoir zones were predicted by overlapping the favorable reservoir facies belt with paleokarst geomorphology. The study results provide a new idea and reference for the exploration deployment of the Middle Permian Maokou Formation in the Sichuan Basin.

Since the Anyue Gasfield, located in the central Sichuan paleo-uplift of the Sichuan Basin, was discovered, great efforts have been made to work on natural gas exploration and discovery in the Sinian–Lower Paleozoic in the north slope of present paleo-uplift which has similar depositional settings. It is verified by the breakthrough of natural gas exploration in the second Member of Upper Sinian Dengying Formation in the north slope of central Sichuan paleo-uplift by wildcat well PT1 and the new sign of natural gas exploration in the Canglangpu Formation of Lower Cambrian and the fourth Member of Dengying Formation by Well JT1 that there are also favorable conditions for the formation of large-scale gas province in the north slope. In order to determine the natural gas exploration potential of Sinian–Lower Paleozoic in the central Sichuan paleo-uplift and provide the guidance for the following exploration deployment, this paper analyzed the petroleum geological conditions of Sinian–Lower Paleozoic in the north slope. And the following research results were obtained. First, the marginal platform belts in the second and the fourth Member of Sinian Dengying Formation in the north slope are basically separated areally, and they are superior to the Gaoshiti–Moxi area in terms of marginal platform width and sedimentary thickness and are intrinsically advantageous in sedimentation. Second, compared with the Gaoshiti–Moxi area, the reservoirs of Sinian Dengying Formation in the north slope are better in reservoir conditions, and many sets of quality reservoirs are developed vertically in Sinian–Cambrian. Third, hydrocarbon accumulation elements of Sinian Dengying Formation are better allocated in the north slope. Lithological traps are developed with a larger cumulative area. Wells JT1 and PT1 verify that there is gas in the lithological trap of the fourth and the second Member of Dengying Formation and large-scale lithological gas reservoirs are developed in the slope setting. In conclusion, compared with the Gaoshiti–Moxi area, the Sinian–Lower Paleozoic in the north slope is superior in petroleum geological conditions and has the advantage of multi-layer stereoscopic exploration vertically, presenting a great natural gas exploration potential and promising exploration prospects, so it is a new important strategic zone of conventional natural gas exploration in the Sichuan Basin.

Functionally graded materials (FGMs) used in electrical insulation have spatially inhomogeneous dielectric properties (i.e., permittivity or conductivity), which can be applied to relieve localized electric field (E-field) intensification and improve insulation performance. However, previous research shows some limitations in inadequate considerations on the material feasibility, and insufficient universality on material grading type and voltage form. In this study, a material study of silicone rubber (SiR) nanocomposites containing carbon nanotubes (CNTs) is conducted to determine the practical variation range of dielectric properties (both permittivity and conductivity) in joint insulation materials. Then, the optimal design of both multilayer and pointwise FGM joint insulation is investigated under both AC and DC voltage, in which the lower and upper limits of permittivity and conductivity were derived from the experimental results. Experimental results on SiR/CNT nanocomposites indicate that low-amount doping of the CNTs (0-0.5% wt%) can effectively increase the permittivity and conductivity of joint insulation materials. The successive simulation study indicates that compared to uniform joints, cable joints employing optimally designed FGM insulation show a considerable increase in the E-field utilization factor (from 0.08-0.17 to 0.23-0.56), indicating elevated E-field uniformity. Finally, the optimal range of CNT doping ratios is determined to be 0-0.3 wt% from both experimental and simulation results. This study systematically verifies the applicability of FGMs in enhancing the performance of power cable accessories, which can show some guidance to the design and fabrication of advanced power cable systems.

The characteristics, formation time, and origin of the sucrosic dolomite reservoirs in the Permian Qixia Formation of northwestern Sichuan Basin are analyzed. Core and outcrop description and microscopic analysis of the sucrosic dolomite samples are carried out. It is found that the dolomite has typical features different from other kinds of dolomites: (1) This dolomite is generally medium-coarse in crystal size, and often associated with very finely to finely crystalline dolomite and cave-filling dolomite. (2) Typical identification marks of eogenetic karstification are developed at the top of the upward-shallowing sequence. (3) The medium-coarse crystalline sucrosic dolomite is cut by the early diagenetic karst fabric, and is characterized by dolomite with dissolution edge, dolomite vadose silt in pores, and transgression clay filling between the medium-coarse dolomite crystals. The medium-coarse crystalline sucrosic dolomite was formed earlier than the eogenetic karstification. The sucrosic dolomite with occasional cloudy core and clear rim has bright cathodoluminescence, high inclusions temperature, significant negative skewness carbon and oxygen isotopic compositions, and rare-earth element (REE) pattern similar to seawater, indicating it experienced two periods of dolomitization, evaporative concentration reflux-infiltration and penecontemporaneous seawater circulation hydrothermal fluid dolomitization. The study results not only update the understanding on the dolomitization time of Qixia Formation, demonstrate that the sucrosic dolomite can be formed in the penecontemporaneous stage when seawater reflux superimposed with hydrothermal fluid effects, but also show that the taphorogenesis in the Dongwu period began in the Early Permian. Moreover, the dolomite controlled by the grain bank migration and terrain in the slope break appears in bands of large scale, this knowledge provides basis for expanding the exploration field of this type of reservoirs.

Osteoporosis is a common disease that can seriously impair the physical and mental health of the elderly. However, current treatment is unsatisfactory due to the lack of effective therapeutic targets. Abnormal expression and involvement of microRNA‐142 (miR‐142) have been identified in many diseases, including bone‐related diseases. Herein, we explored the effect of miR‐142 on the viability, differentiation and apoptosis of the mouse preosteoblast cell line MC3T3‐E1. We observed that the viability of MC3T3‐E1 cells was significantly inhibited or promoted after transfection of miR‐142 mimic or inhibitor, respectively. The apoptotic rate was dramatically increased by miR‐142 mimic and decreased by inhibitor compared with the negative control group. Bcl‐2 expression was down‐regulated in the miR‐142 mimic group and up‐regulated in the miR‐142 inhibitor group, whereas levels of cleaved caspase‐3 and Bax were increased in the miR‐142 mimic group and reduced in the miR‐142 inhibitor group. Expression changes of Runx2 and Osteocalcin suggest that miR‐142 inhibits the differentiation of osteoblast cells. Moreover, the luciferase reporter assay was used to verify that bone morphogenetic protein 2 (BMP2) is a target of miR‐142. Overexpression of BMP2 repressed the proapoptotic effect of miR‐142 mimic, whereas knockdown of BMP2 abolished the inhibitory effect of miR‐142 inhibitor on the apoptosis of MC3T3‐E1 cells. Furthermore, up‐regulation or down‐regulation of miR‐142 dramatically decreased or increased the ratio of p‐Smad1/5/Smad1 and p‐Smad1/5/Smad5, respectively. Collectively, our results imply that miR‐142 might influence the viability and differentiation of osteoblast cells by regulating BMP2 and BMP/Smad signaling.

As a typical kind of lithologic reservoirs, reef reservoirs are generally featured by their large single-well reservoir thickness, good reservoir physical properties, and high gas well productivity. The Upper Permian Changxing Formation is an important natural gas exploration target in the Sichuan Basin, which hosts a large reef gas reservoir and is mainly distributed along the Kaijiang-Liangping Trough. Comprehensive analyses are implemented to investigate reservoir characteristics and identify controlling factors of reef reservoirs in Changxing Formation in the Eastern Longgang Area, Northeastern Sichuan Basin, including core, logging, and seismic data analyses. Changxing Formation reservoirs in the study area mainly occur in the reef-shoal complex, which are featured by wide distribution, large thickness and generally good physical properties. Reservoir rocks are dominantly composed of bioclastic dolomite and silty-fine dolomite (with grain phantom structure), while the main reservoir space consists of residual intergranular pores, intergranular dissolution pores, and karst vugs. In the seismic profiles, typical mound-shaped chaotic reflections can be clearly seen. It is suggested by the main reservoir development controlling factor analysis that the distributions of reef reservoirs are typically controlled by sedimentary facies belts, while the scale of the reef-shoal complex is determined by the pene-sedimentary micro-paleo-geomorphology. Dolomitization can not only significantly preserve the primary pores but also enhance the permeability of rocks. Moreover, karstification is the key to high-quality reef-shoal reservoirs.

A great breakthrough has been made on oil-gas exploration of the Middle Devonian Guanwushan Formation in Northwest Sichuan Basin. The further exploration shows that the dolomite reservoir is complicated with insufficient investigation. Taking the Middle Devonian Guanwushan Formation as an example, systematic study has been carried out on its reservoir character, mechanism and genesis of dolostone. The field and core data suggest that reservoir types of Guanwushan Formation consist of crystalline dolomite, breccia dolomite and reef dolomite, and reservoir space is characterized by intercrystal (dissolution) pores, residual pores among breccias, intragranular dissolution pores, pockets as well as fractures. Besides, pore structure is of good configuration, showing medium-low porosity and moderate permeability, with average porosity and permeability of 2.23% and 0.44mD respectively, which suggesting fracture-pore and fracture-cavity reservoir. Combined with the previous research, it is suggested that the reservoir of Guanwushan Formation was controlled by facies, dolomitization and two-step karstification, with reef-shoal facies being material base for reservoir development, early dolomitization being key factor for reservoir space preservation, polyphase karstification being foundation for reservoir development and tectogenesis finally finalizing the reservoir.

Domain adaptive object detection aims to build an object detector for the unlabeled target domain by transferring knowledge from a well-labeled source domain, which can alleviate the problem of cumbersome labeling of object detection in cross-scene power transmission line inspection. Remarkable advances are made recently by mitigating distributional shifts via hierarchical domain feature alignment training of detection networks. However, domain adaptive object detection is still limited in learning the invariance representation of multi-scale features. Specifically, the scale of objects varies in the scenes of aerial inspection, which hinders the knowledge transfer from the labeled source domain. In this paper, we propose a multi-scale feature enhanced domain adaptation method for cross-domain object detection of power transmission lines inspection. The proposed method consists of two components: 1) Multi-Scale Fusion Feature Alignment module (MSFA) to strengthen similar representation characteristics of different scales object in domain adaptive by utilizing context information conveyed from other levels; 2) Multi-Scale Consistency Regularization module (MSCR) to jointly optimize the multi-scale feature learning of each level, which promotes domain invariant feature learning at each level. Experimental results demonstrate that our method significantly increases the performance of the object detector in several cross-scene transmission line inspection tasks.

Superpixel segmentation could be of benefit to computer vision tasks due to its perceptually meaningful results with similar appearance and location. To obtain the accurate superpixel segmentation, existing methods introduce geodesic distance to fit the object boundaries. However, conventional geodesic distance easily suffers from error accumulation and excessive time consumption. This paper proposes a fast superpixel segmentation method based on a new geodesic distance, called forgetting geodesic distance. In contrast to the conventional geodesic distance, the forgetting geodesic distance utilizes a forgetting factor to gradually reduce the influence of previous path cost and focuses on the latest pixels’ difference. Intuitively, a pixel with lower difference with respect to the latest path contextual distance will be more similar with the corresponding region. In the new path, the path cost devotes much greater attention to the latest pixels’ difference and could significantly relieve error accumulation. The pixels are also aggregated with less dependence on seeds as the path extends, which avoids the seed updating. The experimental results validate that the proposed method obtains 2 percent and 1 percent gain on average compared with most of the state-of-the-art methods in terms of BSD500 and VOC2012 datasets, respectively.