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To alleviate the difficulty in detecting and recognizing erect rail barricades, a forward-looking three-dimensional(3D) imaging sonar is used to improve the effectiveness of erect rail barricade recognition, and a single shot detector(SSD)-based 3D point cloud(PCSSD) target recognition method is proposed. First, the original beam domain data are processed using a threshold filter and pass-through filter. Next, forward projection of the filtered 3D point cloud data is performed, and the grayscale depth image and pseudo color depth image are obtained. The SSD was then used to recognize the targets from the pseudo color depth image. Subsequently, the depth range of the selected targets is calculated based on the characteristics of the targets recognized from the grayscale depth image. Finally, erect rail barricades in the form of 3D point clouds were detected by combining the two-dimensional detection results and the corresponding depth range. A feature extraction block based on the multi-scale attention mechanism was proposed, and a novel target detector SSD-MV3ME was used for the design. On the 3D point cloud erect rail barricades dataset GTZ, under the condition of the same detection time, the detection accuracy of SSD-MV3ME was higher than that of the lightweight target detection model SSD-MV3 by 1.05%, and the model parameters had less than 2 482 kB. The results show that the PCSSD based on SSD-MV3ME is more suitable for erect rail barricade recognition tasks.

By using nuclear magnetic resonance (NMR) and CT scanning technologies, hydration experiments have been conducted on shale samples from the Lower Silurian Longmaxi Formation in Zhaotong area in North Yunnan and Guizhou Provinces under the confining pressure of 10 MPa to study the effect of hydration on the propagation of pores and natural fractures in shale formation. The results show that the hydration not only offsets the permeability drop caused by confining pressure, but makes the fracture network more complicated, the connection between fractures and pores better with larger volume, and permeability higher by facilitating the dilation, propagation and cross-connection of primary pores, natural fractures, and newly created micro-fractures; hydration damage mainly occurs along the bedding plane or the direction of primary fractures; samples with better-developed primary pores and fractures are most affected by hydration, samples with best-developed primary pores and natural fractures are less affected by hydration, samples with only pores are least affected by hydration; and the hydration intensity of shale plugs is affected by the development of primary pores and fractures, clay content, brittleness index, confining pressure and the hydration duration jointly. Therefore, in shale reservoir stimulation, it is suggested that the pumping schedule, shut-in operation or clean-up with small choke during early flow-back process be considered according to the features of shale reservoir to enhance the complexity and connection of facture network and improve the stimulation effect. Key words: shale reservoir, stimulation, flow-back process, hydration, NMR, CT scanning, pores and natural fractures

Objective: To observe the effect of acupoint catgut embedding on the expression of nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) inflammasome, interleukin (IL)-1β and IL-18 in the uterine tissue of primary dysmenorrhea (PD) rats, so as to explore its underlying mechanisms in improving PD., Methods: Forty female SD rats were randomly divided into control, model, acupoint catgut embedding and medication groups ( n ＝10 in each group). The PD model was established by subcutaneous injection of Estradiol Benzoate (0.5 mg/rat on the 1 st and 10 th day, and 0.2 mg/rat from 2 nd to 9 th day) and Oxytocin (2 U/rat, i．p.). The catgut embedding was applied to bilateral "Sanyinjiao" (SP6) and "Guanyuan" (CV4) on the 1 st and 5 th day after modeling. Rats of the medication group were treated by intragastric perfusion of Fenbid (0.8 mL/rat, 125 mg/100 mL) once daily for 10 days. The body writhing times in 30 min were recorded. The histopathological changes of the uterine were observed by H．E. staining. Western blot was used to detect the expression of NLRP 3, caspase-1, IL-1β and IL-18 in uterine tissues., Results: The body writhing times were notably more in the model group than in the control group ( P <0.01), and obviously fewer in both medication and catgut embedding groups than in the model group ( P <0.05, P <0.01). After modeling, the rats' endometrium was extensively exfoliated and got swelling, the histopathological score and the expression levels of NLRP3, caspase-1, IL-1β and IL-18 proteins in the uterus tissue were evidently increased in the model group relevant to the control group ( P <0.01). Following the treatment, the degree of endometrial exfoliation and edema of the uterus tissue was lightened, the pathological score was significantly reduced ( P <0.01), and the expression levels of caspase-1, IL-1β and IL-18 protein in uterus tissue were markedly decreased in both acupoint catgut embedding and medication groups ( P <0.01, P <0.05). The NLRP3 protein expression was significantly decreased in the acupoint catgut embedding group compared with that in the model group ( P <0.01). The therapeutic effect of acupoint catgut embedding was significantly superior to that of medication in reducing writhing times and down-regulating expression of NLPR3 protein ( P <0.01). No significant differences were found between catgut embedding and medication in histopathological score, and expression levels of caspase-1, IL-1β and IL-18 proteins ( P >0.05)., Conclusion: The acupoint catgut embedding can significantly alleviate the symptoms and pathological damage in PD rats, which may be related to its effect in inhibiting the activation of NLRP3 inflammasome in the uterine tissue.

Smoke water and distillation liquid were used to treat the seeds of Trichosathes kirilowii and to study the effects of smoke water and distillation liquid on the seed germination and seedling growth of T. kirilowii. The results showed that germination rate, germination index and germination vigor of T. kirilowii all were significantly improved with the treatment of SW and DL treatment. The activity of α-amylase were significantly increased with the treatment of SW and DL at 1:2,000. SW and DL treatment showed no significant effects on the activity of SOD. The activity of POD were markedly enhanced under the treatment of SW (1:000) and DL (1:2,000). CAT activity were increased with the treatment of SW and DL at 1:2,000 while were inhibited by SW and DL at 1:500. Seedling height and root length were increased with the treatment of SW and DL (1:1,000, 1:2,000). SW and DL treaments improved the content of chlorophyll, and moreover with the concentration of SW and DL, the stimulatory were also increased. This work demonstrated that smoke water and diatillation liquid at 1:2,000 could stimulate the seed germination and seedling growth of T. kirilowii, and it provided the references for the study of seed germination technology.