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As a commonly used traditional Chinese medicine formula for treating rheumatoid arthritis (RA), Sishen Decoction (SSD) has anti-inflammatory, analgesic and swelling relief effects. However, at present, the pharmacodynamic basis of SSD and its mechanism of treating RA have not been clarified, and further research is needed. Analyzing the pharmacological basis of SSD was the aim of our study and further elucidate its therapeutic mechanism and potential targets for treating RA. LC‒MS was used to identify the high content and characteristic chemical components of SSD. On this basis, a network of pharmacological analysis was established between the chemical structure and RA. According to the predicted possible pathways and targets, in vivo pharmacodynamic experiments and related pathway analysis were conducted. Finally, the possible targets and mechanisms of SSD in treating RA were analyzed. Identified 78 compounds from SSD by LC-MS, including 23 flavonoids, 19 phenolic acids, 9 monoterpenoids and 26 other compounds. Network pharmacological analysis based on pharmacodynamic substances revealed that the most likely interaction pathway between SSD and RA was the PI3K/AKT/mTOR pathway. Foot swelling and inflammatory factors (IL-6, IL-10, IL-18, TGF, TNF-α, VEGF) in model mice were shown to be significantly improved in vivo. WB and qPCR experiments proved that SSD could significantly regulate the pathway of PI3K/AKT/mTOR. The interaction between SSD and AKT target was further analyzed by multispectroscopy. This study revealed that SSD alleviates RA by regulating the pathway of PI3K/AKT/mTOR and preliminarily revealed the pharmacodynamic mechanism of SSD for the first time.

Rotundic acid (RA), an ursane-type pentacyclic triterpene acid isolated from the dried barks of Ilex rotunda Thunb. (Aquifoliaceae), possesses diverse bioactivities. To further study its pharmacokinetics, a simple and sensitive liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS/MS) method was developed and validated to quantify RA concentration in rat plasma and tissue using etofesalamide as an internal standard (IS). Plasma and tissue samples were subjected to one-step protein precipitation. Chromatographic separation was achieved on a ZORBAX Eclipse XDB-C18 column (4.6 mm × 50 mm, 5 μm) under gradient conditions with eluents of methanol:acetonitrile (1:1, V/V) and 5 mM ammonium formate:methanol (9:1, V/V) at 0.5 mL/min. Multiple reaction monitoring transitions were performed at m/z 487.30 → 437.30 for RA and m/z 256.10 → 227.10 for IS in the negative mode. The developed LC-QqQ-MS/MS method exhibited good linearity (2–500 ng/mL) and was fully validated in accordance with U.S. Food and Drug Administration bioanalytical guidelines. Dose proportionality and bioavailability in rats were determined by comparing pharmacokinetic data after single oral (10, 20, and 40 mg/kg) and intravenous (10 mg/kg) administration of RA. Tissue distribution was studied following oral administration at 20 mg/kg. The results showed that the absolute bioavailability of RA after administration at different doses ranged from 16.1% to 19.4%. RA showed good dose proportionality over a dose range of 10–40 mg/kg. RA was rapidly absorbed in a dose-dependent manner and highly distributed in the liver. In conclusion, this study is the first to systematically elucidate the absorption and distribution characteristics of RA in rats, which can provide additional information for further development and evaluation of RA in drug metabolism and pharmacokinetic studies.

Deoxyglycychloxazol (TY501) is a glycyrrhetinic acid derivative which exhibits high anti-inflammatory activity and reduced pseudoaldosteronism compared to glycyrrhetinic acid. In this study, a sensitive and rapid liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was established for the quantitation of TY501 in rat plasma. Plasma samples were treated by precipitating protein with methanol and supernatants were separated by a Symmetry C8 column with the mobile phase consisting of methanol and 10 mM ammonium formate (containing 0.1% of formic acid) (90:10, v/v). The selected reaction monitoring (SRM) transitions were performed at m/z 647.4→191.2 for TY501 and m/z 473.3→143.3 for astragaloside aglycone (IS) in the positive ion mode with atmospheric pressure chemical ionization (APCI) source. Calibration curve was linear over the concentration range of 5–5000 ng/mL. The lower limit of quantification was 5 ng/mL. The mean recovery was over 88%. The intra- and inter-day precisions were lower than 6.0% and 12.8%, respectively, and the accuracy was within ±1.3%. TY501 was stable under usual storage conditions and handling procedure. The validated method has been successfully applied to a pharmacokinetic study after oral administration of TY501 to rats at a dosage of 10 mg/kg.

Surrounding rocks of underground engineering are subjected to long-term seepage pressure, which can deteriorate the mechanical properties and cause serious disasters. In order to understand the impact of seepage pressure on the mechanical property of sandstone, uniaxial compression tests, P-wave velocity measurements, and nuclear magnetic resonance (NMR) tests were conducted on saturated sandstone samples with varied seepage pressures (i.e. 0 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa). The results demonstrate that the mechanical parameters (uniaxial compressive strength, peak strain, elastic modulus, and brittleness index), total energy, elastic strain energy, as well as elastic strain energy ratio, decrease with increasing seepage pressure, while the dissipation energy and dissipation energy ratio increase. Moreover, as seepage pressure increases, the micro-pores gradually transform into meso-pores and macro-pores. This increases the cumulative porosity of sandstone and decreases P-wave velocity. The numerical results indicate that as seepage pressure rises, the number of tensile cracks increases progressively, the angle range of microcracks is basically from 50°-120° to 80°-100°, and as a result, the failure mode transforms to the tensile-shear mixed failure mode. Finally, the effects of seepage pressure on mechanical properties were discussed. The results show that decrease in the effective stress and cohesion under the action of seepage pressure could lead to deterioration of strength behaviors of sandstone.

The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering. The shear strength and failure mechanisms of layered rock are significantly affected by the foliation angles. Direct shear tests were conducted on cubic slate samples with foliation angles of 0°, 30°, 45°, 60°, and 90°. The effect of foliation angles on failure patterns, acoustic emission (AE) characteristics, and shear strength parameters was analyzed. Based on AE characteristics, the slate failure process could be divided into four stages: quiet period, step-like increasing period, dramatic increasing period, and remission period. A new empirical expression of cohesion for layered rock was proposed, which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous experiments. The comparative analysis demonstrated that the new expression has better prediction ability than other expressions. The proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method (FDEM), and it was found to align well with the experimental results. Considering both computational efficiency and accuracy, it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear simulations. To balance the relationship between the number of elements and the simulation results in the direct shear simulations, the recommended element size is 1 mm.

The flow and diffusion of grout within rock fractures, as well as the shear behavior of the grout-rock interface, are notably influenced by grouting conditions, encompassing grouting parameters and geological considerations. Regrettably, owing to constraints imposed by prevailing testing techniques, there exists a scarcity of reports investigating the shear mechanical properties of the grout-rock interface across diverse grouting conditions. This study used a low-field nuclear magnetic resonance (LF-NMR) testing system to conduct permeation grouting tests on fractured sandstones under various grouting conditions, followed by direct shear mechanical tests on the post-grouted samples. The influences of grouting pressure, temperature and confining pressure on the shear mechanical properties of the bonding interface were analyzed. Results showed that higher grouting pressure and temperature conditions led to ductile shear failures due to shear-friction action. An increase in grouting pressure (from 0.5 MPa to 1.3 MPa) increased the peak shear strength and residual shear strength of the post-grouted sample. However, increasing the temperature (from 20 °C to 50 °C) and confining pressure (from 5 MPa to 15 MPa) decreased the peak shear strength and residual shear strength. Meanwhile, with increasing the temperature, both the internal friction angle and cohesion linearly decline, while an increase in confining pressure decreased the internal friction angle but increased cohesion. A shear mechanical model was developed for the bonded interface that accounted for the influences of temperature and confining pressure. Additionally, SEM and XRD examinations yielded valuable insights into the grout filling patterns across various grouting parameters. The findings in this study shed light on the intricacies of grouting performance influenced by grouting conditions, and provide essential guidance for grouting operations in practical engineering.

When shield TBM tunnelling in abrasive sandy ground, the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling efficiency. However, the influence mechanism of cutter parameters on scraper wear remains unclear due to the lack of a reliable test method. Geometry and material optimisation are often based on subjective experience, which is unfavourable for improving scraper geological adaptability. In the present study, the newly developed WHU-SAT soil abrasion test was used to evaluate the variation in scraper wear with cutter geometry, material and hardness. The influence mechanism of cutter parameters on scraper wear has been revealed according to the scratch characteristics of the scraper surface. Cutter geometry and material parameters have been optimised to reduce scraper wear. The results indicate that the variation in scraper wear with cutter geometry is related to the cutting resistance, frictional resistance and stress distribution. An appropriate increase in the front angle (or back angle) reduces the cutting resistance (or frictional resistance), while an excessive increase in the front angle (or back angle) reduces the edge angle and causes stress concentration. The optimal front angle, back angle and edge angle for quartz sand samples are α = 25°, β = 10° and γ = 55°, respectively. The wear resistance of the modelled scrapers made of different metal materials is related to the chemical elements and microstructure. The wear resistances of the modelled scrapers made of 45#, 06Cr19Ni10, 42CrMo4 and 40CrNiMoA are 0.569, 0.661, 0.691 and 0.728 times those made of WC-Co, respectively. When the alloy hardness is less than 47 HRC (or greater than 58 HRC), scraper wear decreases slowly with increasing alloy hardness as the scratch depth of the particle asperity on the metal surface stabilizes at a high (or low) level. However, when the alloy hardness is between 47 HRC and 58 HRC, scraper wear decreases rapidly with increasing alloy hardness as the scratch depth transitions from high to low levels. The sensitive hardness interval and recommended hardness interval for quartz sand are [47, 58] and [58, 62], respectively. The present study provides a reference for optimising scraper parameters and improving cutterhead adaptability in abrasive sandy ground tunnelling.

Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones, and its reinforcement effectiveness is highly affected by geostress. In this study, a numerical manifold method (NMM) based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation. To develop this simulator, a detection technique for identifying slurry migration channels and an improved fluid-solid coupling (F–S) framework, which considers the influence of fracture properties and geostress states, is developed and incorporated into a zero-thickness cohesive element (ZE) based NMM (Co-NMM) for simulating tunnel excavation. Additionally, to simulate coagulation of injected slurry, a bonding repair algorithm is further proposed based on the ZE model. To verify the accuracy of the proposed simulator, a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced, and the results align well with analytical and laboratory test results. Furthermore, these numerical results show that neglecting the influence of geostress condition can lead to a serious overestimation of slurry migration range and reinforcement effectiveness. After validations, a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted. Based on these simulations, the influence of geostress conditions and the optimization of grouting schemes are discussed.

An earthquake is usually followed by a considerable number of aftershocks that play a significant role in earthquake-induced landslides. During the aftershock, the cracking process in rocks becomes more complex because of the formation of faults. In order to investigate the effects of seismic loading on the cracking processes in a specimen containing a single flaw, a numerical approach based on the bonded-particle model (BPM) was adopted to study the seismic loading applied in two orthogonal directions. The results reveal that no transmission and reflection phenomena were observable in the small specimens (76 mm × 152 mm) because they were considerably smaller than the wavelength of the P-wave. Furthermore, under seismic loading, the induced crack was solely tensile in nature. Repeated axial seismic loading did not induce crack propagation after the first axial seismic loading. Cracks began to propagate only when the seismic loading direction was changed from axial to lateral, and then back to axial, ultimately resulting in the failure of the specimen.

Based on data from the Jilin Water Diversion Tunnels from the Songhua River (China), an improved and real-time prediction method optimized by multi-algorithm for tunnel boring machine (TBM) cutter-head torque is presented. Firstly, a function excluding invalid and abnormal data is established to distinguish TBM operating state, and a feature selection method based on the SelectKBest algorithm is proposed. Accordingly, ten features that are most closely related to the cutter-head torque are selected as input variables, which, in descending order of influence, include the sum of motor torque, cutter-head power, sum of motor power, sum of motor current, advance rate, cutter-head pressure, total thrust force, penetration rate, cutter-head rotational velocity, and field penetration index. Secondly, a real-time cutter-head torque prediction model's structure is developed, based on the bidirectional long short-term memory (BLSTM) network integrating the dropout algorithm to prevent overfitting. Then, an algorithm to optimize hyperparameters of model based on Bayesian and cross-validation is proposed. Early stopping and checkpoint algorithms are integrated to optimize the training process. Finally, a BLSTM-based real-time cutter-head torque prediction model is developed, which fully utilizes the previous time-series tunneling information. The mean absolute percentage error (MAPE) of the model in the verification section is 7.3%, implying that the presented model is suitable for real-time cutter-head torque prediction. Furthermore, an incremental learning method based on the above base model is introduced to improve the adaptability of the model during the TBM tunneling. Comparison of the prediction performance between the base and incremental learning models in the same tunneling section shows that: (1) the MAPE of the predicted results of the BLSTM-based real-time cutter-head torque prediction model remains below 10%, and both the coefficient of determination (R2) and correlation coefficient (r) between measured and predicted values exceed 0.95; and (2) the incremental learning method is suitable for real-time cutter-head torque prediction and can effectively improve the prediction accuracy and generalization capacity of the model during the excavation process.

The radiated seismic energy is an important index for the intensity assessment of microseismic (MS) events and the early warning of dynamic disasters. However, the energy of MS signals is significantly attenuated due to the heterogeneity and viscous damping of rock media. Therefore, the study on attenuation characteristics of MS signals in underground engineering has practical significance for the accurately estimation of radiated seismic energy. Based on a pendulum impact test facility and MS monitoring system, an in situ investigation was carried out to explore attenuation characteristics at a deep tunnel. The results show that the seismic energy and peak particle velocity (PPV) attenuation are exponentially related to the propagation distance. The attenuation coefficient of energy is larger than that of PPV. With the increase in the input impact-energy, the seismic energy attenuation coefficient decreases as a power function. An empirical relationship between energy attenuation coefficient and wave impedance of rock mass was established in this scenario. Moreover, the time-frequency characteristics and energy distribution laws of impact-induced signals were investigated by the continuous wavelet transform (CWT) and wavelet packet analyses, respectively. The dominant frequency of signals decreases gradually as the propagation distance increases. Based on the energy attenuation characteristics, a new method was proposed to calculate the released source energy of MS events in the field. This study can provide an insight into energy attenuation characteristics of seismic waves and references for attenuation correction in seismic energy calculation.

Real-time perception of rock mass information is of great importance to efficient tunneling and hazard prevention in tunnel boring machines (TBMs). In this study, a TBM–rock mutual feedback perception method based on data mining (DM) is proposed, which takes 10 tunneling parameters related to surrounding rock conditions as input features. For implementation, first, the database of TBM tunneling parameters was established, in which 10,807 tunneling cycles from the Songhua River water conveyance tunnel were accommodated. Then, the spectral clustering (SC) algorithm based on graph theory was introduced to cluster the TBM tunneling data. According to the clustering results and rock mass boreability index, the rock mass conditions were classified into four classes, and the reasonable distribution intervals of the main tunneling parameters corresponding to each class were presented. Meanwhile, based on the deep neural network (DNN), the real-time prediction model regarding different rock conditions was established. Finally, the rationality and adaptability of the proposed method were validated via analyzing the tunneling specific energy, feature importance, and training dataset size. The proposed TBM–rock mutual feedback perception method enables the automatic identification of rock mass conditions and the dynamic adjustment of tunneling parameters during TBM driving. Furthermore, in terms of the prediction performance, the method can predict the rock mass conditions ahead of the tunnel face in real time more accurately than the traditional machine learning prediction methods.

Active matrix (AM) MiniLED backlight units (BLU) on glass substrate is developed to solve severe problems of MiniLED on PCB including insufficient heat dissipation and worse swelling and shrinking performance, as well as limited zone number. However, the MiniLED on glass is observed to possess a weak ability of anti-electrostatic discharge (ESD). The MiniLEDs on glass developed by us (short for MLED) are demonstrated to have a powerful ability of anti-ESD by the means of optimization of peripheral circuit design and metal and dielectric materials, also by the improvements of surroundings of module assembly factory. Consequently, the failure ratio of reliability analysis of MLED is observed to be decreased drastically after the improvements of the ability of anti-ESD.

The significant differences between hard rocks (more brittle) and soft rocks (more ductile) may suggest the use of different failure criteria. A strength criterion for soft rocks that includes intermediate principal stress was proposed. The new criterion includes two independent parameters: the uniaxial compressive strength (σci), which can be obtained from common laboratory tests or indirectly estimated by alternative index tests in the laboratory or field; and f(joint), which is used to characterize the rock mass quality and can be easily estimated. The authors compared the predictive capabilities of the new criterion with other criteria using the database of soft rocks under two conditions: with and without triaxial data. For the estimation of triaxial and true-triaxial strengths, the new criterion generally produced a better fit. The proposed criterion is practical for an approximate first estimation of rock mass strength, even without triaxial data, as it balances accuracy (lower prediction error) and simplicity (fewer independent parameters).

The work presents a novel pixel circuit which breaks the constraint that the PWM driving method combined with internal compensating is unable to achieve a high-bit display. By adding another TFT to transform the equal division of PWM to unequally divided subfields, the bit of a 240 Hz 10-row panel is improved from 3 bits to 8 bits, which is a great breakthrough for bits improving in the fields of PWM driving and internal compensating. Furthermore, simulation results of the original 6T1C circuit and revised 7T1C circuit demonstrate that the current error ratio is almost the same, indicating that this revising 7T1C circuit is suitable for bits improving without sacrificing the circuit margin.

In the current study, the Rossby waves envelope near the equator is studied starting from a potential vorticity equation with the horizontal component of Coriolis parameter. Based on the equation, we first establish the amplitude evolution equation of the Rossby waves with complete Coriolis parameter and obtain rational function solutions by means of the subsidiary ordinary differential equation method with the help of chirp-free hypothesis. Then the 1-, 2-, 3-and N-soliton solutions are also obtained by the Hirota method. For these obtained solutions, they are rarely mentioned in fluid mechanics of ocean and atmospheric motion. On the other hand, these three-dimensional stereograms of the 1-, 2-soliton solutions are depicted with the physical parameter changing. The influence of each parameter on wave amplitude, the peak position and propagation direction of Rossby waves are discussed. The results show that the horizontal Coriolis parameter only alter the phase shift of the Rossby waves amplitude for the 1-soliton and 2-soliton solution. These results are of great significance for further theoretical research in geophysical fluid.

Water-bearing rocks exposed to freezing temperature can be subjected to freeze–thaw cycles leading to crack initiation and propagation, which are the main causes of frost damage to rocks. Based on the Griffith theory of brittle fracture mechanics, the crack initiation criterion, propagation direction, and crack length under freezing pressure and far-field stress are analyzed. Furthermore, a calculation method is proposed for the stress intensity factor (SIF) of the crack tip under non-uniformly distributed freezing pressure. The formulae for the crack/fracture propagation direction and length of the wing crack under freezing pressure are obtained, and the mechanism for coalescence of adjacent cracks is investigated. In addition, the necessary conditions for different coalescence modes of cracks are studied. Using the topology theory, a new algorithm for frost crack propagation is proposed, which has the capability to define the crack growth path and identify and update the cracked elements. A model that incorporates multiple cracks is built by ANSYS and then imported into FLAC3D. The SIFs are then calculated using a FISH procedure, and the growth path of the freezing cracks after several calculation steps is demonstrated using the new algorithm. The proposed method can be applied to rocks containing fillings such as detritus and slurry.