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It is essential to research into the supporting and repairing technologies for ensuring the difficult roadways safety. Based on the widely field investigation including the surrounding environments and supporting technologies of the rock and coal roadways with large deformation, such as in Tangkou, Liuzhuang, Huajiahu, Xinzhi coal mine, etc, the preliminary combining supporting styles and the corresponding effect for the rock roadways are analyzed and concluded. The corresponding supporting technologies for the difficult roadways, such as the roadways with large cross section, soft surrounding rock, intensively dynamic pressure, compound roof, high ground stress, water seepage in the roof or two sides and the influence of the roadways nearby, are studied theoretically and also concluded. Finally, some subsidiary contents are brought forward to control the roadway deformation, which include concrete parameters, the quality of supporting materials, the building of monitoring system.

Background Processed Chuanwu (PCW), the mother root of Aconitum carmichaeliiDebeauxv, has been widely used as a classic Traditional Chinese Medicine for pain relieve for over two millennia clinically. However, its action on chronic inflammatory pain has not been clarified. Here, we investigated the antinociceptive effect of PCW in complete freund’s adjuvant (CFA)-induced mice and its possible mechanisms associated with opioid system and TRPV1 ion channel. Methods Male ICR mice were intraplantarly injected with CFA. PCW (0.34, 0.68 and 1.35 g/kg) was orally given to mice once a day for 7 days. Von frey hairs and planter test were assessed to evaluate the antinociceptive effect of PCW. To investigate the participation of dynorphin/opioid system in PCW antinociception, subtype-specific opioid receptor antagonists or anti-dynorphin A antiserum were used. To eliminate other central mechanisms that contribute to PCW antinociception, hot plate (50 °C) test were performed. Further, involvements of TRPV1 in PCW antinociception were evaluated in CFA-induced TRPV1−/− and TRPV1+/+ C57BL/6 male mice, and in capsaicin-induced nociception ICR naive mice pretreated with nor-BNI. Meanwhile, calcium imaging was performed in HEK293T-TRPV1 cells. Finally, rotarod, open-field tests and body temperature measurement were carried out to assess side effects of PCW. Results PCW dose-dependently attenuated mechanical and heat hypersensitivities with no tolerance, which could be partially attenuated by coadministration of k-opioid receptor antagonist nor-binaltorphimine (nor-BNI) or anti-dynorphin A (1–13) antiserum. And PCW antinociception was totally erased by pretreatment with nor-BNI in the hot plate test. In addition, PCW antinociception was decreased in TRPV1−/− mice compared to TRPV1+/+ group. And PCW still manifested inhibitory effects in capsaicin-induced nociception with nor-BNI pretreatment. PCW significantly inhibited capsaicin-induced calcium influx in HEK293T-TRPV1 cells. Finally, no detectable side effects were found in naive mice treated with PCW. Conclusions This study shows PCW’s potent antinociceptive effect in inflammatory conditions without obvious side effects. This effect may result from the activation of κ-opioid receptor via dynorpin release and the inhibition of TRPV1. These findings indicate that PCW might be a potential agent for the management of chronic inflammatory pain.

Most of the previous research on concrete-filled steel tube is restricted to a deterministic approach. To gain clear insight into the random properties of circular concrete-filled steel tube, reliability analysis is carried out in the present study. To obtain the structural nonlinear response and ultimate resistance capacity, material and geometrical nonlinear analysis of circular concrete-filled steel tube is performed with a three-dimensional degenerated beam element. Then we investigate the reliability of concrete-filled steel tube using the first-order reliability method combined with nonlinear finite element analysis. The influences of such parameters as material strength, slenderness, initial geometrical imperfection, etc. on the reliability of circular concrete-filled steel tube column are studied. It can be concluded that inevitable random fluctuation of those parameters has significant influence on structural reliability, and that stochastic or reliability methods can provide a more rational and subjective evaluation on the safety of CFT structures than a deterministic approach.