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The blasting vibration signal obtained from tunnel construction monitoring is affected by the external environment, which contains a lot of noise that causes distortion during signal processing. To analyse the blasting vibration signal and determine the appropriate water seal blasting charge structure for construction, combined with wavelet threshold denoising method and HHT transformation, the blasting vibration signals of the four charge structures of conventional charge, water interval charge at both ends, water interval charge at the orifice, and water interval charge at the hole bottom are denoised and HHT is analysed. The results show that the wavelet threshold method can effectively eliminate high-frequency noise in the blasting vibration signals and retain information carried by the vibration signal itself. The frequency and energy of the blasting vibration signals of the water interval charge at both ends are densely distributed in the range of 0 s to 0.9 s and below 100 Hz. The frequency and energy of the blasting signals of the other three charging structures are reduced within the same range, sparse areas appear, and the instantaneous total energy is smaller than that with a water interval charge at both ends, which shows that the water interval charge at both ends can effectively apply explosive energy to the surrounding rock and reduce energy loss in the explosive. The blasting vibration signal energy of the water interval charge at both ends is mainly concentrated in components IMF2 to IMF5, and the corresponding frequencies are concentrated at 6 Hz to 11 Hz and 20 Hz to 70 Hz, while the blasting vibration signal energy of other three charge structures is mainly distributed in components IMF2 to IMF4, corresponding frequencies are concentrated within 20 Hz to 70 Hz, and the distribution at low frequencies is not obvious. Therefore, when using the water interval charge at both ends, it is necessary to increase the main vibration frequency of the original vibration signals by reducing the single section charge and using frequency shift technology to avoid the natural frequency of the structure and reduce resonance-induced damage.

Based on Huolangyu tunnel of Mixing road, this paper researches the monitoring of ground surface vibration and the technology of controlled blasting. Monitoring and analysis results show: The ground surface vibration decline from constructed position to un-constructed position along tunnel excavation direction. The maximum ground surface vibration locates at the shallow position along tunnel cross section. The surface vibration velocity main vibration frequency has more than one advantage frequency, main vibration frequency concentration distribution in 20～40Hz low frequency band. Tunnel driving, the emphasis of the blasting vibration should focus on control of tunnel excavation area has the upper, lining structure and shallow buried in the influence of the surrounding rock; Tunnel through the surface buildings, cannot ignore already forming of blasting seismic effects of tunnel amplification and resonance effect.

The blasting effect is an important factor to influence the stability of the slope blasting construction, understanding the reasons of the slope instability under blasting construction, taking reasonable effective protective measures, which can greatly reduce slope instability phenomena during the construction. Combining with the 111 national highway (Tanghekou ~Beijing boundary) reconstruction project, through numerical simulation, using strength reduction fem for time history analysis, discuss under blast loads slope's the stress field, displacement field and the spread rule of vibration wave, systematically analysis blasting excavation impact on slope stability summarizing in construction process the question should be pay attention ,which can be a guidance for relevant similar engineering design and construction.

The impact of blasting effect is an important factor of dynamic stability in the excavation of rock slope. Based on the sub-grade engineering in Jin-hai Lake of the New Countryside Construction Project, this paper sets up a finite element analysis model for the dynamic response of the cutting slope under the blasting loading. It discusses the stress field, displacement field and the propagation law of the blasting seismic wave, and analyzes the security evaluation criteria of the dynamic stability of cutting slope. What’s more, it makes a systematic analysis on the effects of blasting excavation on the stability of the cutting slope according to blasting vibration monitoring. The research provides referential value to form a correct understanding towards slope damage caused by blasting excavation.

Based on the practice of Huolang-yu tunnel of Mixing road reconstruction, this paper studies the monitoring of ground surface vibration and the technology of controlled blasting. The results show: (1) the ground surface vibration declines from constructed position to non-excavated areas along tunnel excavation direction. (2) The vibration control of wedge cutting holes blasting is the key to reduce or eliminate shallow tunnel vibrating calamity. And the replacement of the multi-stage small wedge cutting holes to the big wedge cutting holes ameliorates blasting vibration and rock fragmentation. (3) The overall monitoring of shallow tunnel blasting vibration and the effects, and optimum of the blasting design not only reduce blasting vibration but also ensure large circulation footage.

The methods of controlling Highway semi-rigid base asphalt pavement cracks and other diseases are always hot fields of road engineering and academic circles. The existing methods are on some degree efficient on delaying the formation and extension of cracks, but the effect is limited with different methods and various mechanisms of preventing cracks. Base on force analysis of pavement, this article presents a new technology of crack controlling which uses intelligent composite materials interlayer. By adding a stress absorbing layer between the asphalt surface layers or the semi-rigid base layers with low modulus, good toughness, self-adaptability and self-control ability, the intelligent composite materials interlayer has a good effect on controlling cracks which has been proved by the theoretical calculations and experimental analysis. As a result, the intelligent composite materials interlayer could efficiently prevent and delay the formation and extension of cracks, the safety and comfort of highway could be improved significantly while the cost of construction and maintenance decreasing. And the service level and social image of the road could also be improved effectively. This research has important academic and application value.

In dividing embryos, a localized elevation in intracellular Ca2+ ([Ca2+]i) at the cleavage furrow has been shown to be essential for cytokinesis. However, the underlying mechanisms for generating and maintaining these [Ca2+]i gradients throughout cytokinesis are not fully understood. In the present study, we analyzed the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) and endoplasmic reticulum (ER) distribution in determining the intracellular Ca2+ gradients in early zebrafish blastomeres. Application of the injected Ca2+ indicator, Indo-1, showed that during the first cell division a standing Ca2+ gradient was formed ∼35 min after fertilization, with the [Ca2+]i spatially decaying from 500–600 nmol/L at the cleavage furrow to 100–200 nmol/L around the nucleus. While the IP3R immunohistochemical fluorescence was relatively concentrated in the peri-furrow region, ER labeling was relatively enriched in both peri-furrow and peri-nuclear regions. Numeric simulation suggested that a divergence in the spatial distribution of IP3R and the locations of Ca2+ uptake within the ER was essential for the formation of a standing Ca2+ gradient, and the Ca2+ gradient could only be well-established under an optimal stoichiometry of Ca2+ uptake and release. Indeed, while inhibition of IP3R Ca2+ release blocked the generation of the Ca2+ gradient at a lower [Ca2+]i level, both Ca2+ release stimulation by inositol 1,4,5-trisphosphate (IP3) injection and ER Ca2+ pump inhibition by cyclopiazonic acid also eliminated the Ca2+ gradients at higher [Ca2+]i levels. Our results suggest a dynamic relationship between ER-mediated Ca2+ release and uptake that underlies the maintenance of the perifurrow Ca2+ gradient and is essential for cytokinesis of zebrafish embryos.

To study the target of benzimidazole carbamate drugs against Cysticerci cellulosae and give a theoretical basis for type evolution and new drug design, the changes of key enzyme activities and metabolite contents in the pathway of energy metabolism in C. cellulosae in vitro and in vivo were tested with albendazole and oxfendazole, respectively. Both albendazole and oxfendazole inhibited the pathways of anaerobic glycolysis, partial inversed tricarboxylic acid cycle of Taenia Solium oncosphere, immature and mature Cysticerci in vitro, and immature and mature Cysticerci in vivo to a certain degree, and enhanced fat decomposing, amino acid decomposing, xanthine decomposing metabolism, and on the other hand, the absorption of glucose was hindered; furthermore, both albendazole and oxfendazole inhibited the activities of the fumaric reductase (FR) complex noncompetently in vitro. Benzimidazole carbamate drugs could inhibit the activities of FR complex noncompetently and hinder the absorption of glucose.

Mitogen-activated protein kinase (MAPK) becomes activated during the meiotic maturation of pig oocytes, but its physiological substrate is unknown. The 90-kDa ribosome S6 protein kinase (p90rsk) is the best known MAPK substrate in Xenopus and mouse oocytes. The present study was designed to investigate the expression, phosphorylation, subcellular localization, and possible roles of p90rsk in porcine oocytes during meiotic maturation, fertilization, and parthenogenetic activation. This kinase was partially phosphorylated in oocytes at germinal vesicle (GV) stage through a MAPK-independent mechanism, but its full phosphorylation is dependent on MAPK activity. After fertilization or electrical activation, p90rsk was dephosphorylated shortly before pronucleus formation, which coincided with the inactivation of MAPK. A protein phosphatase inhibitor, okadaic acid, accelerated the phosphorylation of p90rsk during meiotic maturation and induced its rephosphorylation in activated eggs. MAPK kinase (MAPKK or MEK) inhibitor U0126 inhibited the activation of MAPK and p90rsk in both cumulus-enclosed and denuded pig oocytes, but prevented GV breakdown (GVBD) only in cumulus-enclosed oocytes. Active MAPK and p90rsk were detected in pig cumulus cells, and U0126 induced their dephosphorylation. In meiosis II arrested eggs, U0126 led to the inactivation of MAPK and p90rsk, as well as the interphase transition of the eggs. P90rsk was distributed evenly in GV oocytes, but it accumulated in the nucleus before GVBD. It was localized to the meiotic spindle after GVBD and concentrated in the spindle mid zone during emission of the polar bodies. All these results suggest that p90rsk is downstream of MAPK and plays functional roles in the regulation of nuclear status and microtubule organization. Although MAPK and p90rsk activity are not essential for the spontaneous meiotic resumption in denuded oocytes, activation of this cascade in cumulus cells is indispensable for the gonadotropin-induced meiotic resumption of pig oocytes.

The limit equilibrium method is usually used in stability analysis of reinforced roadbed. It considers the function of reinforcing material as equivalent tension and neglects Interaction betweens oil and reinforcing material. Based on the roadbed engineering construction of phase III engineering in Beijing-Chengde Highway, a grid-soil contact element has been constructed to research the application of geogrid in semi-filling and semi-excavating roadbed, and the failure mode and stability of roadbed according to the numerical simulation result is also discussed in this study. We put forward the optimization scheme of reinforcement of using geogrid in semi-filling and semi-excavating roadbed engineering.

Blasting action plays a very important role in slope stability and the effect of rock fragmentation in stonework cutting excavation. Based on engineering practices, this paper applies dynamic finite element method and conducts a numerical simulation of the cutting excavation process. It have conducted researches on the stress field inside rocks in millisecond delay blasting, Von-Mises and other domino effects, as well as the propagation rules for particle vibration velocity. Results show that based on the numerical simulation of the engineering practice, this paper largely represents the real physical mechanical process of the rock fragmentation and can hence serve as a guide for both design and conduction of cutting blasting.

It is well known that MAPK plays pivotal roles in oocyte maturation, but the function of MEK (MAPK kinase) remains unknown. We have studied the expression, subcellular localization and functional roles of MEK during meiotic maturation of mouse oocytes. Firstly, we found that MEK1/2 phoshorylation (p-MEK1/2, indicative of MEK activation) was low in GV (germinal vesicle) stage, increased 2h after GVBD (germinal vesicle breakdown), and reached the maximum at metaphase II. Secondly, we found that P-MEK1/2 was restricted in the GV prior to GVBD. In prometaphase I and metaphase I, P-MEK1/2 was mainly associated with the spindle, especially with the spindle poles. At anaphase I and telophase I, p-MEK1/2 became diffusely distributed in the region between the separating chromosomes, and then became associated with the midbody. The association of p-MEK1/2 with spindle poles was further confirmed by its colocalization with the centrosomal proteins, gamma-tubulin and NuMA. Thirdly, we have investigated the possible functional role of MEK1/2 activation by intravenous administration and intrabursal injection of a specific MEK inhibitor, U0126, and by microinjection of MEK siRNA into oocytes. All these manipulations cause disorganized spindle poles and spindle structure, misaligned chromosomes and larger than normal polar bodies. Our results suggest that MEK1/2 may function as a centrosomal protein and may have roles in microtubule organization, spindle pole tethering and asymmetric division during mouse oocyte maturation.

Mitogen-activated protein kinase (MAPK) becomes activated during the meiotic maturation of pig oocytes, but its physiological substrate is unknown. The 90-kDa ribosome S6 protein kinase (p90rsk) is the best known MAPK substrate in Xenopus and mouse oocytes. The present study was designed to investigate the expression, phosphorylation, subcellular localization, and possible roles of p90rsk in porcine oocytes during meiotic maturation, fertilization, and parthenogenetic activation. This kinase was partially phosphorylated in oocytes at germinal vesicle (GV) stage through a MAPK-independent mechanism, but its full phosphorylation is dependent on MAPK activity. After fertilization or electrical activation, p90rsk was dephosphorylated shortly before pronucleus formation, which coincided with the inactivation of MAPK. A protein phosphatase inhibitor, okadaic acid, accelerated the phosphorylation of p90rsk during meiotic maturation and induced its rephosphorylation in activated eggs. MAPK kinase (MAPKK or MEK) inhibitor U0126 inhibited the activation of MAPK and p90rsk in both cumulus-enclosed and denuded pig oocytes, but prevented GV breakdown (GVBD) only in cumulus-enclosed oocytes. Active MAPK and p90rsk were detected in pig cumulus cells, and U0126 induced their dephosphorylation. In meiosis II arrested eggs, U0126 led to the inactivation of MAPK and p90rsk, as well as the interphase transition of the eggs. P90rsk was distributed evenly in GV oocytes, but it accumulated in the nucleus before GVBD. It was localized to the meiotic spindle after GVBD and concentrated in the spindle mid zone during emission of the polar bodies. All these results suggest that p90rsk is downstream of MAPK and plays functional roles in the regulation of nuclear status and microtubule organization. Although MAPK and p90rsk activity are not essential for the spontaneous meiotic resumption in denuded oocytes, activation of this cascade in cumulus cells is indispensable for the gonadotropin-induced meiotic resumption of pig oocytes.