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Extracellular vesicles (EVs) are cell-derived membrane-enclosed structures that deliver biomolecules for intercellular communication. Developing visualization methods to elucidate the spatiotemporal dynamics of EVs' behaviors will facilitate their understanding and translation. With a quantum dot (QD) labeling strategy, a single particle tracking (SPT) platform is proposed here for dissecting the dynamic behaviors of EVs. The interplays between tumor cell-derived small EVs (T-sEVs) and endothelial cells (ECs) are specifically investigated based on this platform. It is revealed that, following a clathrin-mediated endocytosis by ECs, T-sEVs are transported to the perinuclear region in a typical three-stage pattern. Importantly, T-sEVs frequently interact with and finally enter lysosomes, followed by quick release of their carried miRNAs. This study, for the first time, reports the entire process and detailed dynamics of T-sEV transportation and cargo-release in ECs, leading to better understanding of their proangiogenic functions. Additionally, the QD-based SPT technique will help uncover more secrets of sEV-mediated cell-cell communication.

A patch-based method for detecting vehicle logos using prior knowledge is proposed. By representing the coarse region of the logo with the weight matrix of patch intensity and position, the proposed method is robust to bad and complex environmental conditions. The bounding-box of the logo is extracted by a thershloding approach. Experimental results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions, indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications.

The pore water pressure of tailings dam has a very great influence on the stability of tailings dam. Based on the assumption of one-dimensional consolidation and small strain, the partial differential equation of pore water pressure is deduced. The obtained differential equation can be simplified based on the parameters which are constants. According to the characteristics of the tailings dam, the pore water pressure of the tailings dam can be divided into the slope dam segment, dry beach segment, and artificial lake segment. The pore water pressure is obtained through solving the partial differential equation by separation variable method. On this basis, the dissipation and accumulation of pore water pressure of the upstream tailings dam are analyzed. The example of typical tailings is introduced to elaborate the applicability of the analytic solution. What is more, the application of pore water pressure in tailings dam is discussed. The research results have important scientific and engineering application value for the stability of tailings dam.

Chamber earth pressure is one of the significant parameters during the Earth Pressure Balance (EPB) shield construction processing. The soil arching effect is existence when the tunnel depth is enough. It is significant to consider the influence of arching effect to analyze the pressure in soil chamber in shield tunneling. In this paper, the influence of arching effect is considered to calculate the chamber earth pressure. Firstly, the soil is supposed as loose media, and the necessary buried depth of producing arching affects is deduced according to the loose media theory. Then, based on the characteristic of proper arching axis, the equation and the height of proper arch are obtained. At last, the calculation formula of minimum chamber earth pressure of EPB shield tunnel is deduced which can consider the effect of arching effect.

Area cost estimation model is important for accurate measurement of area on reconfigurable processor. However, in the process of CI (Custom Instruction), traditional model can’t accurately estimate area cost of CI candidates. In the paper, we propose a novel strategy of area cost estimation. According to island-style FPGA (Field Programmable Gate Array) structure, the strategy firstly enumerated all BCs (Basic Cells) from data-path of CI candidates. Then checked all the validity of BCs enumerated, and selected the unique BC set to overlap original data-paths. We lastly used the effective estimation model based on BC to accurately measure area cost of candidates. Experimental results show that novel strategy can accurately estimate area cost of CI candidates, which is very close to actual result from a HLS (High Level Synthesis) tool, and deviation is less than 6%.

the effect of dynamic change activities of enzymatic in Sugarcane field with different coating material was studied With three kinds of coated compound fertilizer as raw materials. Results show that the soil enzymatic activities of catalase,sucrase and urease increased first and then decreased at different sugarcane growth stage; By comparing the Coated compound fertilizer of coated materials ofIdesia polycarpavar.vestitawith CK, we realized the quantity of soil catalase increased 0.03mol/L、that of soil sucrase increased 0.91 mg/g、that of soil urease increased 0.05 mg/g and that of the production increased 23.7%. That was beneficial to the improvement of soil enzyme activity of coated compound fertilizer as raw materials oil ofIdesia polycarpa var.vestita.

The shear stress transfer of prestressed anchor is the key for anchor performance and engineering design. The interface bonding strength between soil and induration has a very important role in supporting capacity of the soil anchor. It is presumed that the deformation between the soil layer rod and induration is compatible after the sliding section. Based on the Mindlin solution of a force act on the interior of a semi-infinite solid, a theory solution for the shear load of anchorage section is solved by considering the part of slip characteristics of interface in the loading process. On this basis, the shear stress of anchorage section is tested from anchor pullout test on site. Contrasted with the tests result, it is proved that the theoretical analysis is consistent with the tests. Theoretically, the research of shear stress transfer will enrich and develop anchor cable theory.

Fulvic acid solution whose the pH value is at 2.9 and 3.5 is adopted to conduct immersion test of three days cured red clay-cemented soil composite mass. Through monitoring the acid consumption and specimen appearance, the corrosivity and mechanism of red clay-cemented soil composite mass while under the fulvic acid circumstances is studied. It is showed that fulvic acid has some corrosivity to the composite mass. The smaller pH value is, and the more severe corrosivity is. The erosion process can be divided into quick response and stable stages, where the former stage is the primary and the latter is weak.

The soil layers around the tunnel were equal to cohesionless homogenate mass by introducing the concept of equivalent internal frictionangle in this paper. Based on the Terzarghi unconsolidated mass theory, the soil arching effect of existing open trench tunnels under ground asymmetric load is discussed. Furthermore, the critical embedded depth formula of soil arching effect is given. Finally, it is concluded that both the size and distribution of the ground asymmetric load have influence on soil arching effect of existing open trench tunnel.

In order to study the soil nail optimization of foundation pit and obtain the global optimal solution, this paper establishes the predictive model of response surface by combining uniform test design(UD) and the support vector machine(SVM) technology. In order to avoid the disadvantages of large amount of calculation and low efficiency in heuristic algorithm, and to gain the optimal model of the explicitly analytical function in gradient algorithm, based on the predictive model of response surface under the constraint conditions, the foundation pit soil nailing is optimized through the application of enumerative algorithm. Through an engineering example, it is showed that is a time-saving method and don't need explicitly analytical model. Meanwhile, it can obtain the global optimal solution.

foundation pit, pile-anchor support, optimization design, uniform test, SVM response surface

Traditional analysis methods of reliability in the foundation pit engineering have larger error and larger amount of calculation. Therefore, the response surface method has attracted much attention because it can effectively use the finite element analysis method (FEAM) and reduce the number of the numerical simulation. This paper combines uniform design (UD) with support vector machine (SVM). On this base, a reliability analysis method of the foundation pit is put forward based on the response surface of support vector machine (RSSVM). The UD structures random samples and the FEAM is used to obtain corresponding response parameters including the lateral displacement of wall, settlement of ground, safety factor of overall stability and safety factor of against overturning. Then, SVM trains the above random samples and corresponding response parameters to get response surface (RS) respectively. The probability density distribution of each response parameter is obtained by combining the Monte Carlo method with RSSVM. The instance analysis shows that the method has high computing efficiency and less amount of calculation, and the result is reasonable. It provides an effective way for the reliability analysis of the foundation pit engineering.

The double-row piles retaining structure (DRPRS) is widely applied in the excavation engineering, but its calculation theory is immature and in appropriate. Based on the theory of earth pressure distribution, the distribution characteristics of earth pressure is analyzed to different layout form, and the general formula of earth pressure is derived. From the perspectives of the morphology of slip surface, linear slip surface morphology and broken-line slip surface morphology are proposed based on the feature of the DRPRS. A new calculation model is proposed combining the earth pressure and slip surface morphology. On this basis, one example is used to analyze the force and deformation mechanism of the DRPRS in detail. The research results can guide the engineering practices and promote the development of calculation theory for the DRPRS.

Sensitivity analysis of double-row piles is often obtained by changing the value of single influencing factor and doesn’t considering the interaction of influencing factors. So, a new sensitivity analysis method is proposed which can consider the interaction of influencing factors. In this method, uniform design (UD) and alternating conditional expectations regression (ACE) are used. The embedded depth of the forward pile, row space, length of the back pile, equivalent thickness of forward pile, equivalent thickness of coupling beam, and equivalent thickness of back pile are six input parameters called influencing factors. The maximum horizontal displacement of the pile head (MDP), maximum bending moment of forward pile (MMF), maximum ground settlement (GS), and coefficient of global stabilization (CGS) are four outputs as target parameters. The sensitivity can be obtained in this geological condition, excavation depth and surrounding environment. It is showed that the stiffness of back pile is the critical influence factor to MDP, the stiffness of forward pile is the critical influence factor to MMF and GS, and the length of back pile is the critical influence factor to CGS.

The bedding high rock slope is most likely to failure in the rock slopes. It is the sliding and bending deformation model (buckling failure) according to deformation characteristic of the north wing slope at the open-pit mine. Considering the influence of rocky self-weight, seismic force and groundwater, the failure mechanism of bedding high rock slope by energy method is researched on the basis of stability theory for elastic plane. And the critical length is obtained. Finally, the influences of model geometry on the critical length, such as the rock stratum dip angle, thickness and width length ratio, is analyzed.

The tailings dam is a very important component part in mine production facilities. Meanwhile, it is a potential major risk source with high potential energy. Through collecting many accidents of the tailings dam, it is showed that accident type of the tailings dam mainly is dam-break, damage of drainage system, leakage of tailings, etc. On the basis of this analysis, the main causes of dam-break are slope instability, breaking construction rule, unusual rainfall, etc. The automatic safety monitoring and management system of the tailings reservoir (ASMMS) is a powerful measure for mine safety production. The basic frame of the ASMMS is proposed. The main contents and key problems of the ASMMS are also analyzed. It can provide a strong theoretical and technical basis for the safety and management of the tailings dam.