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Abundant coal and oil shale resources are developed in the coal-bearing member of the Shimengou Formation (J2sh1) in the northern Qaidam Basin, NW China. A better understanding of the formation mechanism of these oil shales is of great significance for the exploration of potential unconventional oil and gas resources, and the co-development of coal and oil shale resources. In this study, the geochemistry of 16 samples from drilling cores was used to determine paleoclimate, paleosalinity, redox conditions, chemical weathering intensity, provenance, and tectonic setting. The results show that the geochemical characteristics of the samples are similar to the composition of the upper continental crust, with a warm and humid paleoclimate, a freshwater to brackish paleosalinity condition, a generally anoxic condition, and intense weathering during the Middle Jurassic. The provenance was mainly felsic igneous rocks, and the prevailing tectonic setting was passive margin. During the Middle Jurassic, the warm and humid climate, caused by the low paleolatitude and water vapor from the Tethys Ocean, made the provenance mainly from Hercynian intrusive rocks, which underwent intense weathering and entered the northern Qaidam Basin along with plant material. During water regression periods, abundant terrestrial plants formed coal, while during flooding periods, the increasing water depth and the input of nutrients from terrestrial debris promoted the development of lake algae. Algae and other lake organisms, as well as terrestrial plants, provided the material basis for the formation of organic matter. The anoxic preservation conditions enabled the preservation of organic matter, resulting in the formation of oil shale. This study helps to understand the formation mechanism of the J2sh1 oil shale and promotes the utilization of oil shale in the studied area.

In the cascaded H-bridge inverter (CHBI) with supercapacitor and dc-dc stage, inherent second-order harmonic power flows through each submodule (SM), causing fluctuations in both the dc-link voltage and the dc-dc current. There exist limitations in handling these fluctuations at variable output frequencies when employing proportional-integral (PI) control to the dc-dc stage. This paper aims to coordinately control these second-order harmonic voltage and current fluctuations in the CHBI. The presented method configures a specific second-order harmonic voltage reference, equipped with a maximum voltage fluctuation constraint and a suitable phase, for the dc-dc stage. A PI-resonant controller is used to track the configured reference. This allows for regulating the second-order harmonic fluctuation in the average dc-link voltage among the SMs within a certain value. Importantly, the second-order harmonic fluctuation in the dc-dc current can also be reduced. Simulation and experimental results demonstrate the effectiveness of the presented method.

Abiotic and biotic stressors adversely affect plant survival, biomass generation, and crop yields. As the global availability of arable land declines and the impacts of global warming intensify, such stressors may have increasingly pronounced effects on agricultural productivity. Currently, researchers face the overarching challenge of comprehensively enhancing plant resilience to abiotic and biotic stressors. The secondary cell wall plays a crucial role in bolstering the stress resistance of plants. To increase plant resistance to stress through genetic manipulation of the secondary cell wall, we cloned a cell wall protein designated glycine-rich protein-like (GhGRPL) from cotton fibers, and found that it is specifically expressed during the period of secondary cell wall biosynthesis. Notably, this protein differs from its Arabidopsis homolog, AtGRP, since its glycine-rich domain is deficient in glycine residues. GhGRPL is involved in secondary cell wall deposition. Upregulation of GhGRPL enhances lignin accumulation and, consequently, the thickness of the secondary cell walls, thereby increasing the plant's resistance to abiotic stressors, such as drought and salinity, and biotic threats, including Verticillium dahliae infection. Conversely, interference with GhGRPL expression in cotton reduces lignin accumulation and compromises that resistance. Taken together, our findings elucidate the role of GhGRPL in regulating secondary cell wall development through its influence on lignin deposition, which, in turn, reinforces cell wall robustness and impermeability. These findings highlight the promising near-future prospect of adopting GhGRPL as a viable, effective approach for enhancing plant resilience to abiotic and biotic stress factors.

Cascaded H-bridge inverter (CHBI) with supercapacitors (SCs) and dc-dc stage shows significant promise for medium to high voltage energy storage applications. This paper investigates the voltage balance of capacitors within the CHBI, including both the dc-link capacitors and SCs. Balance control over the dc-link capacitor voltages is realized by the dc-dc stage in each submodule (SM), while a hybrid modulation strategy (HMS) is implemented in the H-bridge to balance the SC voltages among the SMs. Meanwhile, the dc-link voltage fluctuations are analyzed under the HMS. A virtual voltage variable is introduced to coordinate the balancing of dc-link capacitor voltages and SC voltages. Compared to the balancing method that solely considers the SC voltages, the presented method reduces the dc-link voltage fluctuations without affecting the voltage balance of SCS. Finally, both simulation and experimental results verify the effectiveness of the presented method.

Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results.

Skin, as the outermost protective barrier of the body, becomes damaged with age and exposure to external stimuli. Dermal fibroblasts age and undergo apoptosis, which decreases collagen, collagen fibers, elastic fibers, hyaluronic acid, etc., leading skin to loss of elasticity and appearance of wrinkles. Skin aging is complex, involving several biological reactions，and various treatment methods are used to treat it. This review focuses on the importance of autophagy and cell proliferation in skin anti-aging, summarizes research progress on skin anti-aging by regulating autophagy and promoting the proliferation of dermal fibroblasts, and discusses future directions on skin anti-aging research.

As a global metabolic disease, the control and treatment of diabetes have always been the focus of medical research. α-Glucosidase is a key enzyme in regulating blood glucose levels and has important applications in the treatment of diabetes. This review aims to explore the enzyme activity of α-glucosidase and its inhibition mechanism and evaluate the efficacy and limitations of existing inhibitor screening methods. First, the chemical structure, biological activity, and influencing factors of α-glucosidase on diabetes are discussed in detail. Then, the various methods that have been used to screen α-glucosidase inhibitors in recent years are reviewed, including in vivo animal experiments, in vitro experiments, and virtual molecular docking. The experimental principles, advantages, and limitations of each method and their application in discovering new inhibitors are also discussed. Finally, this review emphasizes the importance of developing efficient and safe α-glucosidase inhibitors, summarizes the advantages and disadvantages of various screening models, and proposes future research directions. This review comprehensively examines the enzyme activity of α-glucosidase and the screening methods for α-glucosidase inhibitors, provides an important perspective in the field of diabetes drug discovery and development, and provides a reference for future research.

Abstract Transarterial chemoembolisation (TACE) is a standard therapy for hepatocellular carcinoma (HCC). However, adverse events, including abdominal pain, are common. This study aimed to investigate and verify the feasibility of a nomogram model to predict severe abdominal pain after first conventional TACE (cTACE) among patients with HCC. Patients with HCC treated with cTACE between October 28, 2019, and August 5, 2022, at a single centre were enrolled (n = 216). Patients were divided into training and validation cohorts (ratio, 7:3). A visual analogue scale score between 7 and 10 was considered severe abdominal pain. A total of 127 (58.8%) patients complained of severe abdominal pain after first cTACE treatment. The nomogram considered age and tumour number and size. The nomogram demonstrated good discrimination, with a C-index of 0.749 (95% confidence interval [CI], 0.617, 0.881). Further, the C-index in the validation cohort reached 0.728 (95% CI 0.592, 0.864). The calibration curves showed ideal agreement between the prediction and real observations, and the nomogram decision curve analysis performed well. The nomogram model can provide an accurate prediction of severe abdominal pain in patients with HCC after first cTACE, aiding in the personalization of pain management and providing novel insights into hospital nursing.

Abstract Titanium (Ti) dental implants face risks of early failure due to bacterial adhesion and biofilm formation. It is thus necessary to endow the implant surface with antibacterial ability. In this study, magnesium oxide (MgO) coatings were prepared on Ti by combining micro-arc oxidation (MAO) and electrophoretic deposition (EPD). The MgO nanoparticles homogeneously deposited on the microporous surface of MAO-treated Ti, yielding increasing coverage with the EPD time increased to 15 to 60 s. After co-culture with Porphyromonas gingivalis (P. gingivalis) for 24 h, 48 h, and 72 h, the coatings produced antibacterial rates of 4–53 %, 27–71 %, and 39–79 %, respectively, in a dose-dependent manner. Overall, EPD for 45 s offered satisfactory comprehensive performance, with an antibacterial rate 79 % at 72 h and a relative cell viability 85 % at 5 d. Electron and fluorescence microscopies revealed that, both the density of adherent bacterial adhesion on the surface and the proportion of viable bacteria decreased with the EPD time. The morphology of cells on the surface of each group was intact and there was no significant difference among the groups. These results show that, the MgO coating deposited on MAO-treated Ti by EPD had reasonably good in vitro antibacterial properties and cytocompatibility.

To enable unmanned aerial vehicles to generate coverage paths that balance inspection quality and efficiency when performing three-dimensional inspection tasks, we propose a quality and efficiency coupled iterative coverage path planning (QECI-CPP) method. First, starting from a cleaned and refined mesh model, this was segmented into narrow and normal spaces, each with distinct constraint settings. During the initialization phase of viewpoint generation, factors such as image resolution and orthogonality degree were considered to enhance the inspection quality along the path. Then, the optimization objective was designed to simultaneously consider inspection quality and efficiency, with the relative importance of these factors adjustable according to specific task requirements. Through iterative adjustments and optimizations, the coverage path was continuously refined. In numerical simulations, the proposed method was compared with three other classic methods, evaluated across five aspects: image resolution, orthogonality degree, path distance, computation time, and total path cost. The comparative simulation results show that the QECI-CPP achieves maximum image resolution and orthogonality degree while maintaining inspection efficiency within a moderate computation time, demonstrating the effectiveness of the proposed method. Additionally, the flexibility of the planned path is validated by adjusting the weight coefficient in the optimized objective function.

Cotton fiber is a raw material for the global textile industry and fiber quality is essential to its industrial application. Carotenoids are plant secondary metabolites that may serve as dietary components, regulate light harvesting, and scavenge reactive oxygen species. Although carotenoids accumulate predominantly in rapidly elongating cotton fibers, their roles in cotton fiber development remain poorly understood. In this study, a fiber-specific promoter proSCFP was applied to drive the expression of GhOR1Del, a positive regulator of carotenoid accumulation, to upregulate the carotenoid level in cotton fiber in planta. Fiber length, strength, and fineness were increased in proSCFP:GhOR1Del transgenic cotton and abscisic acid (ABA) and ethylene contents were increased in elongating fibers. The ABA downstream regulator GhbZIP27a stimulated the expression of the ethylene synthase gene GhACO3 by binding to its promoter, suggesting that ABA promoted fiber elongation by increasing ethylene production. These findings suggest the involvement of carotenoids and ABA signaling in promoting cotton fiber elongation and provide a strategy for improving cotton fiber quality.

To clarify the influence of the serpentine nozzle configurations on the flow characteristics and aerodynamic performance of aircraft, the flow features and aerodynamic performances of the double-ducted serpentine nozzles with different aspect ratios (AR), length–diameter ratios (LDR) and shielding ratios (SR) are numerically investigated. The results show that the asymmetric nozzle flow occurs due to the curved profile of serpentine nozzles, and a local accelerating effect exists at the S-bend, causing the increase in wall shear stress. The unilateral unsymmetrical expansion of the tail jet in the upward direction interacts with the separated external flow of the afterbody, forming an obvious cross-shock wave and shear layer structure. The surface pressure of the afterbody increases along the external flow direction, and decreases sharply in the separation point of the boundary layer. With the increase in AR and LDR, the local accelerating effect of the nozzle flow weakens, while with the increase in SR, the accelerating effect increases. The total pressure recovery coefficient, flow coefficient and axial thrust coefficient all decrease with the increase in AR, LDR, and SR. The thrust vector angle decreases with the increase in AR but is less affected by LDR and SR.

At present, there are many methods to construct a vehicle driving cycle, such as the micro-trip-based method and the Markov chain method. Different methods have different advantages and disadvantages. To compare these methods, this paper uses the micro-trip-based method, the Markov chain method, and the method combining micro-trips and Markov chains to construct the representative driving cycle of a Xi’an urban bus based on the driving data of the Xi’an No.2 bus. Firstly, the driving data is collected and preprocessed. Then, representative driving cycles are constructed based on different methods. Finally, different driving cycles based on different methods are compared. By calculating and comparing characteristic parameters, velocity distributions, acceleration distributions, and vehicle-specific power distributions between different representative driving cycles, this paper shows the advantages and disadvantages of different construction methods.

Article Highlights 1. We propose a Bayesian MCMC procedure for surface-based TEM data inversion and apply it successfully both in synthetic data and field data. 2. We use the modified Gaussian proposal distribution to improve the sampling efficiency and deep resistivity resolution. 3. The results of Bayesian can provide uncertainty information on parameters and judge the reliability of inversion results.

Distribution characteristics, organic matter development characteristics, gas-bearing characteristics, reservoir characteristics, and preservation conditions of the Shahezi Formation shale of Lower Cretaceous in the Lishu fault depression, Songliao Basin, NE China, are analyzed using organic geochemical, whole rock, and SEM analysis data, and CO2 and N2 adsorption and high-pressure mercury injection experiment data in combination with the tectonic and sedimentation evolution of the region to reveal the geological conditions for enrichment and resource potential of continental shale gas. The organic-rich shale in the Lower Cretaceous of the Lishu fault depression is mainly developed in the lower submember of the second member of the Shahezi Formation (K1sh21 Fm.) and is thick and stable in distribution. The shale has high TOC, mainly types II1 and II2 organic matter, and is in the mature to the over-mature stage. The volcanic activity, salinization, and reduction of the water environment are conducive to the formation of the organic-rich shale. The shale reservoirs have mainly clay mineral intergranular pores, organic matter pores, carbonate mineral dissolution pores, and foliated microfractures as storage space. The pores are in the mesopore range of 10–50 nm, and the microfractures are mostly 5–10 μm wide. Massive argillaceous rocks of lowland and highstand domains are deposited above and below the gas-bearing shale separately in the lower submember of the K1sh21 Fm., act as the natural roof and floor in the process of shale gas accumulation and preservation, and control the shale gas enrichment. Based on the above understandings, the first shale gas exploration well in Shahezi Formation was drilled in the Lishu fault depression of Songliao Basin. After fracturing, the well tested a daily gas production of 7.6×104 m3 marking a breakthrough in continental shale gas exploration in the Shahezi Formation (K1sh Fm.) of the Lishu fault depression in Songliao Basin. The exploration practice has reference significance for the exploration of continental shale gas in the Lower Cretaceous of Songliao Basin and its periphery.

The procoagulant effect of microparticles (MPs) contributes to hypercoagulability-induced thrombosis. We provide preliminary findings of the MPs-Activated Clotting Time (MPs-ACT) assay to determine the procoagulant activity of MPs. MPs-rich plasma was obtained and recalcified. Changes in plasma viscoelasticity were evaluated and the time to the peak viscoelastic changes was defined as the MPs-ACT. MPs concentration was measured by flow cytometry. Coagulation products produced during plasma clotting were identified by fibrin and fibrinopeptide A. MPs were prepared in vitro and added to standard plasma to simulate pathological samples. In addition, reproducibility and sensitivity were evaluated. We confirmed the linear relationship between MPs-ACT and MP concentrations. Dynamic changes in fibrin production were depicted. We simulated the correlation between MPs-ACT and standard plasma containing MPs prepared in vitro. The reproducibility of high-value and low-value samples was 6.0% and 10.8%, respectively. MPs-ACT sensitively detected hypercoagulable samples from patients with pre-eclampsia, hip fractures, and lung tumors. MPs-ACT largely reflects the procoagulant effect of MPs. MPs-ACT sensitively and rapidly detects hypercoagulability with MPs-rich plasma. It may be promising for the diagnosis of hypercoagulable states induced by MPs.

Abstract Spin squeezing is a key resource in quantum metrology, allowing improvements of measurement signal-to-noise ratio. Its generation is a challenging task because the experimental realization of the required squeezing interaction remains difficult. Here, we propose a generic scheme to synthesize spin squeezing in non-squeezing systems. By using periodical rotation pulses, the original non-squeezing interaction can be transformed into squeezing interaction, with significantly enhanced interaction strength. The sign of the interaction coefficient is also flippable, facilitating time-reversal readout protocol for nonlinear interferometers. The generated spin squeezing is capable of achieving the Heisenberg limit with measurement precision ∝ 1/N for N particles and its robustness to noises of pulse areas and separations has been verified as well. This work offers a path to extending the scope of Heisenberg-limited quantum precision measurements in non-squeezing systems.

When an intelligent vehicle changes lanes, the state of other vehicles may change, which increases the risk of collision. Therefore, real-time local path replanning is needed at this time. Based on model predictive control (MPC), a lane-change trajectory replanning strategy was proposed, which was divided into a lane-change trajectory correction strategy, a lane-change switchback strategy and forward active collision avoidance strategy according to collision risk. Based on the collision risk function of the rectangular safety neighborhood, the objective functions were designed according to the specific requirements of different strategies. The vehicle lateral controller based on MPC and the vehicle longitudinal motion controller were established. The longitudinal velocity was taken as the joint point to establish the lateral and longitudinal integrated controller. The trajectory planning module, trajectory replanning module and trajectory tracking module were integrated in layers, and the three trajectory replanning strategies of lane-change trajectory correction, lane-change switchback and forward active collision avoidance were respectively simulated and verified. The simulation results showed the trajectory replanning strategy achieves collision avoidance under different scenarios and ensures the vehicle’s driving stability. The trajectory tracking layer achieves accurate tracking of the conventional lane-change trajectory and has good driving stability and comfort.

Aiming at the problem of fixed candidate voltage vector (VV) in conventional finite-control-set (FCS) model predictive torque control (MPTC) of permanent magnet synchronous motor (PMSM), fuzzy control is use to determine dynamic candidate VVs based on effects of the value and angle of applying VV on stator flux and torque. The inputs of fuzzy controller are errors of stator flux and torque and outputs are 3 candidate VVs. Simulation results show compared with conventional FCS-MPTC, the proposed strategy can decrease stator flux and torque’s ripples and calculation burden of MPTC, but it will increase average switching frequency. In order to decrease average switching frequency, zero VV is also used as candidate VV, but it will decrease dynamic torque response. Thus the method that zero VV is used only at steady state is given. Simulation results show the control performance of the system remains basically unchanged and the average switching frequency is reduced.

Aiming at the problem of bad real-time performance caused by the large calculation of the finite control set model predictive torque control(MPTC), a data-driven method for MPTC of the permanent magnet synchronous motor(PMSM) is proposed. The data produced by PMSM-MPTC system are used to train DNN to learn its selective laws and then replace it to select the optimal voltage vector. This paper also analyzes the data-driven out-of-control problems caused by the difference between the steady data and dynamic data of the MPTC and solves the above issue by extending and balancing the data set, which further proves the feasibility of the data-driven MPTC. The simulation experiments show that the torque ripple, stator flux ripple and the system switching frequency of the data-driven MPTC are further reduced, indicating has certain superiority.

Simplified models to calculate the change of stator flux and torque of permanent magnet synchronous motor (PMSM) on stator flux coordinate system are proposed. In order to solve high torque ripples of PMSM direct torque control (DTC) system, dead-beat (DB) control of stator flux and torque is proposed. The calculation of ideal voltage vector (VV) for the DB control of stator flux and torque using simplified models are given, and a simplified VV selecting method is used to implement the DB control. In order to improve control performances, a novel way to expand VVs based on both angle and amplitude is proposed. The angle and amplitude of ideal VV are used to determine the angle and amplitude of output VV and the look-up table is used to generate output VVs. Simulation results show this novel method can decrease stator flux and torque ripples dramatically, but increase switching frequency.

Aiming at reducing computational complexity in the multi-step model predictive torque control (MPTC), a novel simplified multi-step MPTC algorithm (P-MPTC) was proposed. Firstly, a multi-step MPTC model was established, and the computational burden of the traditional MPTC (T-MPTC) was discussed. Secondly, based on the MPTC with simplified voltage set (S-MPTC), a simplified MPTC with voltage holding approach (P-MPTC) was proposed, which avoided enumerating all the voltage vectors in candidate set to simplify the computation. Finally, the proposed MPTC algorithm was compared with T-MPTC and S-MPTC to analyze the differences of control performance and computational burden. The result shows that, the proposed simplified algorithm can greatly reduce the computational complexity of multi-step MPTC while the control performance almost not change. For example, in the six-step MPTC, the computational burden in the proposed simplified algorithm is only 0.02% of that in the traditional algorithm, which verifies the effectiveness of the proposed algorithm.

Pure shales in the first member of Qingshankou Formation (simplified as Qing 1 Member) in the southern Songliao Basin, i.e., the semi-deep and deep lacustrine shales, are characterized by a high content of clay minerals and poor hydrocarbon mobility, making the development of shale oil difficult. According to the drilling and testing results, the shale of Qing 1 Member can be classified into 3 lithofacies, i.e., bedded argillaceous shale, laminated diamictite shale, and interbedded felsic shale. The TOC and brittle minerals control the enrichment of shale oil, of them, TOC controls the total oil content, in other words, the total oil content increases with the increase of TOC; while the laminae made up of brittle minerals contain a large number of bigger intergranular pores which are favorable enrichment space for movable shale oil. In consideration of the origins of the 3 lithofacies, two shale oil enrichment models are classified, i.e., the deep lacustrine high-TOC bedded argillaceous shale (Model-I) and the semi-deep lacustrine moderate-high-TOC laminated diamictite shale (Model-II). In the Model-I, the shale is characterized by high hydrocarbon generation ability, high total oil content, abundant horizontal bedding fractures, and vertical and high angle fractures locally; the complex fracture network formed by horizontal bedding fractures and vertical fractures improve the storage capacity and permeability of the shale reservoir, increase the enrichment space for movable oil. In the Model-II, the shale is characterized by good hydrocarbon generation ability and fairly high total oil content, and as the brittle laminae contain large intergranular pores, the shale has a higher movable oil content. Based on the two models, shale oil sweet-spot areas of 2880 km2 in the southern Songliao Basin are favorable for further exploration. Aimed at the difficulties in reservoir fracturing of the lacustrine shale with a high content of clay minerals, the composite fracturing technology with supercritical carbon dioxide was used in the shale oil reservoir for the first time, realizing large-scale volume fracturing in shale with a high content of clay minerals and strong heterogeneity, marking a breakthrough of oil exploration in continental shale with a high content of clay minerals in China.