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In a large underground iron mine (over 2000, 000 t/a) in China, a large volume of mined void could not be filled in time, which posed a threat to the working face. Physical and numerical models were used to investigate the stability of the mined void sandwiched between the backfills. Digital image correlation (DIC) method was employed in the physical model to calculate the deformation field of the roof and backfills. Stress meters and multi-point borehole extensometers were installed in the mine to observe the change of vertical stress and horizontal displacement in real backfills. Principal component analysis (PCA) and cluster analysis were applied to classify the deformation state around mined void. The deformation field was exhibited by the contour and curves of displacement, which was consistent between the physical model and numerical simulation. The contour indicated that highly deformed zones were ellipse-shaped and wedge-shaped in the backfills and roof respectively. The deformation process was classified into three states (stable state, transition state, and unstable state) by using the density-based clustering. The data obtained from the in situ monitoring showed that the vertical stress increased by 60–80 kPa and the horizontal deformation was small in the backfills close to mined void. Classification of deformation states indicated that the mined void (temporary opening) remained stable during production plan.

A prospective resource of pharmacological treatment of ischemic brains stroke is rapid interference using potential neuroprotective materials. Cerium oxide nanoparticles have been shown to defend against blood brain barrier damage in cerebral ischemic brain stroke. While cerium oxide nanoparticles is highly permeable across the blood-brain barrier and also these nanoparticles are effective antioxidants, due to its ability to either donate or obtain electrons with alternative +3 and +4 valence states. This oxidation state of cerium oxide has shown efficiency in neutralizing generated free radicals in biological systems has been explored action for cerebral ischemic brain stroke. The nanoparticles are encapsulated on the poly-(lactide-co-glycolide)-polyethyleneglycol copolymer matrixes as nanoparticulate delivery vehicles and it can be enhanced brain targeted drug delivery. Furthermore, the results of spectroscopic and microscopic analysis confirmed that peripheral PEG-PLGA co-polymer chains provide excellent reactivity with nanoparticles which might improve the interface bonds of the nanocomposite formation. Mainly, neuroprotective properties of prepared CeO2-PEG/PLGA matrixes with and without nanoparticles are comparatively studied by using transient middle cerebral artery occlusion (MCAO) model of brain stroke. The prepared CeO2 nanoparticles combined with effective PEG/PLGA matrixes exhibited greater efficacy resulted in a lessening of focal ischemia by 60% and 78% decrease in brain edema in comparable to the control animals. The results are demonstrated that the neuroprotective efficiency of CeO2 nanoparticles with PEG/PLGA has enhanced and primarily protected the brain cortex areas from ischemic damage.

A series of 3-nitro-5-nitroimino-1,2,4-oxadiazole-based energetic salts were synthesized from 3-nitro-5-nitroimino-1,2,4-oxadiazole anion and nitrogen-rich cations. They were fully characterized by IR, elemental analysis and NMR spectroscopy. The structure of triaminoguanidinium salt ( 1-e ) was confirmed by single crystal X-ray diffraction. All salts showed good thermal stability with decomposed temperature ranging from 155 °C to 258 °C, and positive heats of formation from 226.0 kJ/mol to 554.1 kJ/mol. Thus, the theoretic detonation pressure was predicted from 28.70 GPa to 37.60 GPa and velocities from 8526 m/s to 9354 m/s. Among them, guanidinium salt ( 1-c ) exhibited both high decomposition temperature (258 °C) and detonation velocity (9319 m/s).

To investigate the sedative effect of dexmedetomidine in spinal-epidural anesthesia on hysteromyomectomy a total of 100 hysteromyomectomy patients were randomly divided into the control group and the observation group with 50 in each group. Patients in the control group received the general anesthesia, while those in the observation group received spinal-epidural anesthesia, and intravenous injection of dexmedetomidine. For maintenance of anesthesia, ropivacaine was adopted for both groups. Before anesthesia, at 30 min and 60 min after anesthesia, we measured the heart rate (HR), bispectral index (BIS) and sedative effect. Before anesthesia, HR, BIS and Ramsay scores were compared between two groups, and the results showed that differences had no statistical significance (p0.05); but at 30 min after anesthesia, HR and BIS of patients in the observation group were significantly lower than those in the control group (p0.05), and Ramsay score was higher than the control group (p0.05). No statistical significance was found in differences of the incidence rate of adverse reactions between two groups (p0.05). Application of dexmedetomidine in spinal-epidural anesthesia gains promising sedative effect and safety in hysteromyomectomy, which is worthy of being promoted in clinical treatment.

Methods that can efficiently model the effects of rock joints on rock mass behavior can be beneficial in rock engineering. The suitability of equivalent rock mass (ERM) technique based upon particle methods is investigated. The ERM methodology is first validated by comparing calculated and experimental data of lab triaxial compression test on a set of cylindrical rock mass samples, each containing a single joint oriented in various dip angles. The simulated results are then used to study the stress-strain nonlinearity and failure mechanism as a function of the joint dip angle and confining stress. The anisotropy and size effects are also investigated by using multi-scale cubic ERM models subjected to triaxial compression test. The deformation and failure behavior are found to be influenced by joint degradation, the micro-crack formation in the intact rock, the interaction between two joints, and the interactions of micro-cracks and joints.

Based on the condition of fully mechanized caving face in one mine, two methods of microseismic monitoring and numerical analysis were combined to study the evolution characteristics and development law of floor failure depth in extra-thick coal seam. Microseismic monitoring results show that the number of microseismic events partly reflects the influence of mining disturbance in the roof and floor rock mass. The distribution of microseismic events are intensive near the coal mining face, which show the floor rock mass is seriously damaged during the coal mining. The greatest floor failure depth estimated from mine microseismic monitoring is 31 meters. Numerical analysis indicate that the rock stress around the mine stope is redistributed during the coal mining, due to the effect of mining disturbance. The abutment pressure increases in front of the coal mining face and the stress reduces in the mined areas. The concentration and release of the stress makes contribution to the destroy of the floor rock. The maximum floor failure depth is up to 28 meters calculated from numerical simulation. The consistency of microseismic monitoring results and numerical analysis improve that it is effective and reliable to obtain floor failure depth and considerably possible to predict the water inrush using microseismic monitoring technology with its inherent ability to remotely monitor the progressive failure caused by mining. The research results have great popularization and application values for the similar mine.

Taking BaiYu county Ouqu river basin landslide control in Ganzi state of Sichuan province as an example, study the whole design process of lattice frame anchor structure. Firstly, according to the geological conditions and technical code for design, safety criterion for landslide control is confirmed. Secondly, by making use of the features of lattice frame anchor structure this can protect slope and retain stability of landslide together with its small space between beams and light anchor. Finally, the advice and request for construction is specific ally put forward.

The impact disasters of rock burst and pressure bump are common problems of underground construction and deep mining [1-. This paper selected the typical mine based on the work of field crustal stress measurement, indoor rock mechanical experiment, parameter calculation, numerical analysis and field disaster investigation, etc,. Deeply analysed the basic types and potential laws of possible impact disaster after a mines main tunnel excavation based on the study idea of experimental rock mechanics and computational rock mechanics co-ordination and additional verification.

MicroRNAs (miRNA) are believed to play an important role in glioblastoma multiforme (GBM)chemotherapy. Our study aims to investigate potential miRNA biomarkers in GBM. Sixty GBM patients, which were given temozolomide (TMZ) chemotherapy and recurrent radiotherapy, were recruited. miRNA array was performed in cancerous and in paired normal tissues. Microarray results were further validated by a quantitative real-time PCR in selected tissues and GBM cell lines. TMZ resistance cells were developed and cell proliferation along with colony formation assays was determined. Our study employed H2AX formation and flow cytometry to analyse the role of miRNA in DNA damage and apoptosis. Our study illustrated 16 miRNA in which 9 were up-regulated and 7 down-regulated. and their differential expression were demonstrated in a recurrent GBM tissue. Among them, miRNA-370-3p demonstrated the highest level of down- regulation in tissues and in TMZ resistance cells. miRNA-370-3p mimic increased its expression and sensitivity of GBM cells to TMZ by suppressing the self-reparative ability of tumour cell DNA. O6-methylguanine-DNA methyltransferase (MGMT) was identified as the direct target gene of miR-370-3p, and it was found to be inversely correlated with miR-370-3p expression in tissue samples obtained. Thus, our study demonstrated a critical clinical role of an up-regulated miR-370-3p expression in glioblastoma multiforme chemotherapy sensitivity.

Based on mining area end slope stability evaluation engineer- ing of Pingshuo East open pit coal mine in Shanxi Province, ac- cording to the status quo of the North Slope of the first mining district of the East open pit coal mine as well as engineering g- eological investigation results, this article selected a represen- tative cross-section of the North Slope,adopted processing fu- nctions of finite element analysis software MIDAS/GTS, and re- spectively analyze slope stability under three conditions of the mining area of the initial excavation,backfilling and disposal,a- nd follow-up excavation.The paper concluded that Initial exca- vation caused slope instability; backfill slope is stable after di- sposal; follow-up excavation has essentially no effect on slope stability. The establishment and analysis are much closer to t- he real situation, objectively reflect the distribution of slope s- tability of the East open pit coal mine, and provide a design for open pit production safety.

Using penetration resistance methods detect the wall’s mortar strength to masonry structure where in ecological farm of Sichuan Emei, and then obtain the date of field trial. We have calculated the mortar actual strength according technical specification for testing compressive strength of masonry mortar by penetration resistance method, and compare the calculated results with compression tests result, testing specimen from the engineering project field. So we obtain true mortar strength of engineering and corresponding appraisal conclusion.

The construction time of secondary lining in loess tunnel has been the focus of attention in the tunnel field, but no specific quantitative discriminant index of the construction time of the secondary lining has been applied. Relying on the Wofosi tunnel of Zhangjiakou-Zhuolu highway, based on the deformation characteristics and deformation rate analysis of the crown settlement and surrounding convergence, proposed that the stability of basic rate as the indicators of construction time of secondary lining, determined preliminarily the construction time of secondary lining by optimizing the regression model, combined with the characteristics of the rock pressure and pressure distribution state along the hole to determine the best construction time of secondary lining

Water underground is one of the most important factors which influences the strength of the rock and soil. In this study, we get the governing equation and simulate the process of water transportation in rock. Groundwater flow is modeled by a ground-water flow model and the partial differential equations can be solved by using finite element method.

For the aluminum alloy pipe stable form and buckling capacity, axis compressing test for 4 sections which each specification in three members, total 36 members, thus, we work out the ultimate bearing capacity for a little slenderness ratio alloy round pipe and relation between slenderness ratio and coefficient of stability, to provide test data for drawing pillars curve of the same type member. Through observed aluminum alloy compressing member changing with test process, record test phenomenon, and combined with instruments of test data record, providing the basis for further theoretical analysis.

In this paper, seismic behaviors of the frame-shear wall structure, which are composed of the concrete filled steel tubular (CFST) column, have been studied. Dynamic behaviors and earthquake responses of the CFST under rare earthquake are analyzed. Comparing the calculation results, the earthquake resistant behavior of the CFST structure has been appraised synthetically, which may be referential for structural design.

In order to meeting high-rise building anti-wind，anti-seismic and land for construction more angespannter situation of urban construction need, introduced a type of new structure which has advantages of seismic dissipation, a great use of materials with high strength and fewer floor spacing：the suspended structure system with huge concrete-filled tubular steel lattice column. Introduced its main structure form, member type and decorate situation by referenced to high-rise building and involved suspended structure theory，ant same time，we state fundamental way and connecting format to this structure system. So we can realize its design features，meditation and innovation case，lay a foundation for spread this new type of structure popularization and application.

Architectural physical environment is the most important determined elements of people comfortably using architectural space. This paper firstly analyzes the physical environment's constitution for architectural space; uses analytic hierarchy process(AHP) to establish a kind of comprehensive evaluation model for physical environment of architectural space to divide them into three-level evaluation indexes; then calculated the weight value of each index for scheme layer; at the same time, selects four teaching buildings as evaluation instances and provides the value of each index for physical environment of architectural space by experts' scoring method; at last, weights and composites with the foregoing weigh to obtain the comprehensive scores of each teaching buildings and conducts the comprehensive evaluation.

In the interest of forecasting and alarming system of rainfall landslides, the Boji stones landslide of Three Gorges is taken into researching. On basis of the model, its epitomized model is formed to analyze the landslide mechanism and damage model by taking them into consideration: water-level fluctuation in reservoir, rainfall intensity, rainfall capacity and soil mass mechanical property, and decide current stability, predict its tendency and potential risks through applying the monitoring data and quantitative analysis. The research indicates that Boji stone landslide in flowing reservoir is in stability without any extra dynamic

Due to the applicable installation height, small mass, flexible characteristic, and small damp, the adherent billboard could easily result in vibration with the wind effect. The main factor is the turbulence among the cause effects. Combining the structural dynamic theory, and considering the characteristic of the adherent billboard, a wind effect calculation formula is set up considering the turbulent wind that is resulted by the 1st vibration type. Hope to provide some reference for similar structure designs.

As the concrete filled steel tubular has a higher loading capacity, smaller section, stronger rigidity, better deformation and capacity of absorbing energy, besides of its easier construction without formworks, it has a perfect perspective of landslide treatment engineering, while served for anti-slide pile. This paper introduced concrete filled steel tubular briefly, focused on computing formulas of loading capacity and rigidity, and provides references to design of in landslide treatment.

Due to the applicable installation height, small mass, flexible characteristic, large span, so the unit glass curtain wall (UGCW) could be differ from the glass curtain wall of frame members. Based on the characteristic of UGCW, analysis the load of UGCW and building the formula of static wind load, Earthquake Action, Temperature Function etc. The formula to calculate the load of the unit glass curtain wall (UGCW) is given on the base of analyzing the acting load and the mechanism of force transfer of the UGCW in service condition. Hope to provide some reference for similar designs.

The formula to calculate the stability of the unit glass curtain wall (UGCW) is given on the theory of the structure stability is applied to analyze the whole stability of the frame of the UGCW and the calculation formula is provided. Due to the special structure form of the vertical column of the UGCW the formula is given to calculate the critical moment of the vertical column when torsional and flexural buckling occur, and then, the design basis is provided for reasonable and safe design of the UGCW.

During the tunnel excavation in Zhang-Shi Expressway 2nd-Stage Project, rock burst phenomenon has occurred. Limy dolomite obtained from tunnel rock burst area is used to conduct laboratory loading rock burst test with simulation system of deep rock burst. Simultaneously, based on Particle Flow Theory and PFC3D program, a load-unload code is developed by fish language embedded in PFC3D to carry out simulation of laboratory loading rock burst test. Laboratory test result shows that the rock burst type and intensity of specimen are lagged and severe, respectively; During the test process, a spot of particles eject from the exposed surface; Obvious slabbing phenomenon can be seen on the exposed surface and the separate face of rock slab is parallel to the direction of maximal load σ1 as consistent with the actual phenomenon of engineering rock burst. In the loading rock burst simulation, the load grade, stress-step curve and failure mode of rock burst are almost consistent with the laboratory test. This simulation method describes the failure process actually and subtly, and reveals that the specimen fracture mechanism of loading rock burst is tensile type. Finally, some differences between loading and unloading tests of rock burst are discussed.

The traditional method of calculating soil arch effect was described Firstly, and the inadequacy of traditional methods was analyzed. On the basis of their predecessors, the rectangular cross section of a rational spacing between passive pile was mainly discussed. Based on the mechanical properties of soil between anti-slide piles analysis, a pile of soil conditions of static equilibrium, cross-section strength of the section of the conditions and strength condition of the arch to common control methods to determine the critical pile space were put forward.Relatively reasonable a spacing formula for calculating pile spacing has been obtained. Comparing with rational pile space formula obtained and the traditional formula for the actual project data, the results indicate that, for the cross-section 2.5mx2.5m the pile, formula by rational pile space the calculated results and the calculation method has been compared and analyzed the results, when the landslide thrust 47kN/m2.According to rational pile space formula the results calculated by the situation more in line with the actual project, it is of significance to practical engineering design of anti-slide pile, and there is a greater using and reference value for the similar project via the methods used and the conclusion.

Due to the applicable installation height, small mass, flexible characteristic, large span, and small damp, the unit glass curtain wall (UGCW) could easily result in vibration with the wind effect. The main factor is the turbulence among the cause effects. Combining the structural dynamic theory, and considering the characteristic of the UGCW, a wind effect calculation formula is set up considering the turbulent wind that is resulted by the 1st vibration type. Hope to provide some reference for similar designs.

With the unilateral extending test on 4 teams*12 aluminum alloy round pipes, compressing test on 4 teams*4 pipes and repeating extending/compressing test on 4 teams*4 pipes, get the stress-strain relationship of the aluminum alloy round pipe, and get the elastic modulus f0.1 and f0.2. At the same time, get the conclusion that the damaging type is brittleness. The test result is the foundation for follow-up studies on the loading capacity of the aluminum alloys.

To study the seismic behavior under conventional earthquakes, according to a case of Shifang Telecom Building (STB) under 5.12 earthquake, this paper makes the computation of internal force and deformation of structure; then compares the seismic behavior of two different models with spectrum analysis and time-history analysis. The conclusion shows that STB can approximately meet requirements for fortification against seismic impact under conventional earthquakes; the steel tower on top can amplify the seismic effect indeed and the weakness of numerical simulation tallies with the reality.

Based on integral property of unit glazing curtain wall (UGCW), considering the co-effect of glass and grids, set up the calculating method of cooperation of glass and grids; through the numerical simulation analysis with this method, we can conclude that take the glass’s rigidity into consideration is both reasonable and economical.

The earthquake resistant behavior of buildings with steel tower on top is different from ordinary buildings. In order to investigate the deformations, internal force and damage of structure under rare earthquake, based on a case of Shifang Telecom Building (STB) under 5.12 earthquake, the static elasto-plastic analysis is carried out. This paper compares the seismic behavior of structure under different loading cases, and studies the weakness and plastic hinge of the building. The result shows the structure can meet the requirements of non-collapse under rare earthquake, the top steel tower can amplify the seismic effect, and numerical simulation tallies with the reality.

Based on the pseudo-dynamic and pseudo-static under low-cycle test of 10-storey model building without seams and 6-storey model building with seams, the change of dynamic characteristics, the failure mechanism, the deformation feature and ductility of two type structures are discussed. The result of experimental study proves that the capacity of hollow shear wall is well; In elastic stage, the hollow shear wall and common shear wall are similar: high stiffness and little deformation; In elastic-plastic stage, the deformation is increasing, and the slit hollow shear wall are divided into several little walls, the property of energy dissipation of hollow shear wall structure is good. The seismic behavior of the slit and integral hollow shear walls are used in the multi-story and low high-rise building.

An easy preparation of methoxymethyl ethers of primary and secondary alcohols with dimethoxymethane has been carried out in excellent yield under catalysis of expansive graphite.

Due to the applicable installation height, small mass, flexible characteristic, large span, and small damp, the glass curtain wall could easily result in vibration with the wind effect. The main factor is the turbulence among the cause effects. Combining the structural dynamic theory, and considering the characteristic of the glass curtain wall, a wind effect calculation formula is set up considering the turbulent wind that is resulted by the 1st vibration type. Hope to provide some reference for similar designs.

Tongtai Bridge is the world’s largest suspension curve-girder-skew-arch bridge, which is located in Zhangjiakou, China. The understanding of mechanics characteristics is limited to such complex bridges, so it is necessary to establish reliable health monitoring system to investigate the static and dynamic responses and monitor the safety of the bridge. A comprehensive real-time bridge health monitoring system is establish, which includes four aspects: sensor system, data acquisition and transmission system, data processing and control system, structure early warning and security assessment system. The paper systematically describes the system design principles, sensor layout, and monitoring content, then expounds system integration and function of each subsystem.

We aimed to ascertain the role of microRNAs (miRNAs) in regulating human endometrial cancer stem cells (HuECSCs). The expression level of miRNA-134 (miR-134), a member of the DLK1-DIO3 genomic imprinted miRNA cluster, differed significantly between HuECSCs and human endometrial cancer cells (HuECCs). miR-134 inhibited HuECSCs proliferation and migration by targeting protein O-glucosyltransferase 1 (POGLUT1) expression. Exogenous miR-134 overexpression downregulated POGLUT1 and Notch pathway proteins in HuECSCs in vitro. miR-134 overexpression affected the G2/M phase of HuECSCs and suppressed the growth of xenograft tumours formed. Thus, endogenous miR-134 regulation in HuECSCs may suppress tumourigenesis in human endometrial carcinoma.