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Aramid fiber is commonly used for ballistic vests because of its excellent mechanical properties. However, it has a drawback in that the fiber force deteriorates under ultraviolet (UV) irradiation. It is proposed in this paper to grow ZnO nanowires on aramid fabric through the hydrothermal method for improving its UV aging properties. Fourier transform infrared spectroscopy analyses illustrate that there is some damage to the N-H and C-N chemical bonds for bare aramid fabric after UV irradiation, although no significant damage is shown by scanning electron microscopy observation. For fabrics subject to 120 h UV irradiation, the warp and weft tensile force of bare fabric decrease by 38.44% and 18.15%, respectively. However, the warp and weft tensile force of fabric with ZnO nanowires increase by 275.52% and 164.84%, respectively, and remain at 241.67% and 197.13% after UV irradiation, respectively. In addition, the burst force of bare fabric decreases over by 50% due to the UV irradiation. Nevertheless, with ZnO nanowires, the burst force of aramid fabric increases dramatically and the increase percentage is over 200%. Even after the UV irradiation, the burst force of fabric with nanowires still retains almost 30% over the bare fabric.

To study the effect of Jiawei Huangqi Guizhi Decoction on gastrointestinal hormones and TGF-β3 signal pathways in rats with chronic atrophic gastritis (CAG). The model was created by methylnitrosoguanidine (MNNG) comprehensive method. After successful modeling, it was divided into three groups: model group (MC group), frolic acid group (AC group), modified Huangqi Guizhi Decoction high dose group (HH group), modified Huangqi Guizhi Decoction middle dose group (HM group), and modified Huangqi Guizhi Decoction low dose group (HL group). Gastric pathology was observed by HE staining. The levels of gastrin (GAS) and motilin (MTL) in rat serum were detected by ELISA assay. After HE staining, the histopathological sections were analyzed. Inflammatory factors infiltration and disorder of mucosal epithelial cells were found in the model group, which were improved to some extent after administration. According to the pathological chart analysis and score of rats in each group, compared with the model group, the gastric tissue damage of rats in each administration group has been improved in different degrees, among which the pathological scores of HH and HM groups were lower, and the corresponding damage degree was smaller. According to the test results of ELISA, Jiawei Huangqi Guizhi Decoction could reduce the contents of GAS, TGF-β3, and increase MTL abundance in the serum of rats, thus accelerating the apoptosis of tumor cells and inhibiting cancer. Jiawei Huangqi Guizhi Decoction played a positive role in preventing the occurrence of gastric cancer through reducing the concentrations of GAS and TGF-β3 in serum, and increasing the concentration of MLT in serum. This results provided a new treatment idea for CAG.

Predicting Stick-Slips in Sheared Granular Faults Using Machine Learning Optimized Dense Fault Dynamics Data Weihan Huang, Ke Gao, Yu Feng Key Points · LightGBM model is trained using densely distributed fault dynamics data to predict laboratory earthquakes in a sheared granular fault system · The dense fault dynamics data contain sufficient information for prediction; the prediction accuracy can be improved via data optimization · The SHAP value analysis of input data has the potential to unveil the complex underlying fault physics in sheared granular fault The laboratory data simulation used in this study are publicly available in this site. The FDEM simulation datasets are saved as file 'p28_data.bin'. The python program of machine learning algorithm to train and test the data is saved as 'submission_lgbm_model.py'. Besides, the basic parameters setting and functions using in the program are saved as 'submission_setting.py' and 'submission_function_define.py'.

Predicting Stick-Slips in Sheared Granular Faults Using Machine Learning Optimized Dense Fault Dynamics Data Weihan Huang, Ke Gao, Yu Feng Key Points · LightGBM model is trained using densely distributed fault dynamics data to predict laboratory earthquakes in a sheared granular fault system · The dense fault dynamics data contain sufficient information for prediction; the prediction accuracy can be improved via data optimization · The SHAP value analysis of input data has the potential to unveil the complex underlying fault physics in sheared granular fault The laboratory data simulation used in this study are publicly available in this site. The FDEM simulation datasets are saved as file 'p28_data.bin'. The python program of machine learning algorithm to train and test the data is saved as 'submission_lgbm_model.py'. Besides, the basic parameters setting and functions using in the program are saved as 'submission_setting.py' and 'submission_function_define.py'.

In this study, ZnO nanoparticles were prepared by a hydrothermal method with varying the reaction times, material ratios and reaction temperatures. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray Diffraction (XRD) and Fourier infrared spectroscopy (FTIR). It was shown that the material ratio significantly affected the structure and morphology of the synthesized ZnO nanoparticles, and then the uneven nano-octahedral structure, uniform nano-octahedral structure, nano-tubular structure, and nano-sheet structure could be obtained successively. The synthesized ZnO nanoparticles as mordant were used for the dyeing of silk fabrics with different natural dyes (tea polyphenols and hematoxylin). Moreover, they could improve the dyeing properties and fastness (wash and light) on silk fabrics to a certain extent.

Adding surfactants in fracturing fluids is a practical method for enhancing spontaneous imbibition of shale oil reservoirs. However, both positive and negative observations are found in the field practice. The mechanisms of different types of surfactants for enhancing spontaneous imbibition still need further investigation. In this work, we applied the nuclear magnetic resonance technique to measure the fluid distributions in shale pores during the spontaneous imbibition process. We found that surfactants mainly recover oil in the macropores but have less impact on the production of oil in the micropores. Combining with scanning electron microscopy, high-pressure mercury intrusion, and X-ray diffraction experiments, the pore structure and mineral composition of shales are carefully analyzed. We observed that the surfaces of large pores are mostly quartz and feldspars, while the surfaces of small pores are organic matter and clay. The wettability of a shale rock is a key factor affecting spontaneous imbibi...

Background Based on 122 cases reported in China, data mining indicated that Sini Powder (SNP) and the Zuojin Pill (ZJP) are both widely used as the basic recipe for treating Gastroesophageal Reflux Disease (GERD). Objectives To evaluate the intervention effects of Sini Zuojin Decoction (SNZJD) in patients with GERD. Methods A comprehensive collection of randomized controlled trials (RCTs) using SNZJD in patients with GERD that were published in domestic and foreign journals was made by computer retrieval. RevMan 5.3 software was used for meta-analysis and bias risk assessment, Stata 14.0 software was used for sensitivity analysis, GRADE profiler 3.6 was used to evaluate the level of evidence, and trial sequential analysis (TSA), employed to control for random errors, was performed to assess the main outcomes. Network pharmacology analysis was applied to preliminarily study the mechanisms of action of SNZJD on GERD. Results Thirteen articles were eventually included, covering a total of 966 patients. Meta-analysis indicated that: ① the SNZJD plus traditional stomach medicines (SPTSM) group was more effective than the traditional stomach medicines (TSM) group (RR = 1.16, 95% CI [1.04, 1.29], P = 0.009); ② the experimental group with SNZJD was significantly better than TSM controls in improving heartburn, substernal chest pain, acid regurgitation, and food regurgitation symptoms (P < 0.0001); ③ SPTSM could significantly decrease total symptom scores with substantial effectiveness (P < 0.00001). The recurrence rate and adverse effects of SNZJD treatment were significantly reduced (P < 0.05). TSA showed that the effective rate of meta-analysis might be reliable, but the recurrence and safety results were still uncertain. According to the evaluation by the GRADE method, the quality of evidence was low. Besides, SNZJD might treat GERD by acting on related targets and pathways such as inflammation, hormone regulation, and so on. Conclusions SNZJD might be useful in the treatment of GERD, but its long-term effects and specific clinical mechanisms are unclear. Due to the poor quality of the evidence, more samples and high-quality clinical studies should be tested and verified in the future.

This paper introduces a nonlinear, magnetically charged, singularity-free black hole model. The Ricci scalar, Kretschmann scalar, horizon, energy conditions, and Hawking radiation corresponding to the singularity-free metric are presented, and the asymptotic behavior and quantum correction of the model are examined. The model was constructed by coupling a mass function with the regular black hole solution under nonlinear electrodynamics in general relativity. Aside from resolving the problem of singularities in Einstein’s theory of general relativity, the model asymptotically meets the quantum correction under an effective field theory. This obviates the need for additional correction terms; in this regard, the model outperforms the black hole models developed by Bardeen and Hayward. Regarding the nonlinear magnetic monopole source of the gravitational field of the black hole, the energy–momentum tensors fulfill weak energy conditions. The model constitutes a novel, spherically symmetric solution to regular black holes.

Tight sand gas is an important unconventional natural gas. Liquid filtration plays a main role in the formation damage. Flowback rate is closely related to the formation permeability recovery. Usually, the more flowback rate is, the better the permeability recovery is. In order to research the factors that influence the liquid flowback, the tight sand characteristics and gas displacement have been investigated. Some experiments were carried out, including porosity, permeability, XRD, casting thin section, SEM, stress sensitivity, rock expansion, and gas displacement. The results are shown as follows. Taiyuan formation has average high clay content than H8 formation. Illite is the main clay in Taiyuan formation; chlorite is the main clay in H8 formation. From the casting thin section, the rock has strong compression. Taiyuan formation has large pore. However, H8 formation mainly has small cracks. Through the SEM, there are many micro- to nanocracks as well as some pores in these two formations. In some cases, cracks penetrate the clays. From the permeability stress sensitivity, these tight sands have strong stress sensitivity. Permeability decreases quickly with increasing confining pressure. In the rock expansion experiment, the tight sand has less expansion rate compared with shale gas rock and volcanic gas rock. Rock expansion rate has positive relationship with clay content. In the gas displacement experiment, usually the higher the clay content, the lesser the liquid flowback. Some samples have high clay content. However, it has high flowback rate, which may account for good pore connection. Through the above study, the flowback rate has negative relationship with clay content and positive relationship with pore size, pore connection, and displacement pressure. In order to increase tight gas production in the study area, the formation should have high flowback rate and less liquid retention. Therefore, clay expansion preventing additives should be added into the fracturing liquid to reduce the liquid retention. The quick flowback should be implemented after hydraulic fracturing for reducing the interaction between liquid and rock. At the same time, the drawdown pressure should keep in a certain value to reduce stress sensitivity.