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In this paper, a seismic and vibration reduction measure of subway station is developed by setting a segmented isolation layer between the sidewall of structure and the diaphragm wall. The segmented isolation layer consists of a rigid layer and a flexible layer. The rigid layer is installed at the joint section between the structural sidewall and slab, and the flexible layer is installed at the remaining sections. A diaphragm wall-segmented isolation layer-subway station structure system is constructed. Seismic and vibration control performance of the diaphragm wall-segmented isolation layer-subway station structure system is evaluated by the detailed numerical analysis. Firstly, a three-dimensional nonlinear time-history analysis is carried out to study the seismic response of the station structure by considering the effect of different earthquake motions and stiffness of segmented isolation layer. Subsequently, the vibration response of site under training loading is also studied by considering the influence of different train velocities and stiffness of the segmented isolation layer. Numerical results demonstrate that the diaphragm wall-segmented isolation layer-subway station structure system can not only effectively reduce the lateral deformation of station structure, but also reduce the tensile damage of the roof slab. On the other hand, the developed reduction measure can also significantly reduce the vertical peak displacements of site under training loading. [ABSTRACT FROM AUTHOR]

Two thermoplastic polyurethanes (TPUs) based on the same monomers and composition were produced by two different production methods - hand mix batch process and continuous band casting. The soft segment was poly(hydrofuran) (PTHF) with a molar mass of 1000 and the hard segment was made of 1,4-butanediol (BD) and 4,40-methylene diphenyl diisocyanate (MDI). The hard segment content amounted to 42%. The distinctions in crystallization and thermal behavior and mechanical properties of the two TPUs were ascribed to differences in the hard and soft block length distribution caused by the different production methods. Using thermal fractionation - a series of successive self-nucleation and annealing steps - the minor differences in hard block length distribution could be shown and quantified. The length distribution of the hard and soft blocks of the machine-produced sample was narrower than that of the hand-cast sample. The former with the narrow block distribution showed thicker and mechanically and thermally more stable hard domains. The more uniform block length distribution facilitated crystallization and resulted in improved tensile recovery behavior and elasticity. The second with the broader distribution, however, showed the highest tensile strength at break, which was ascribed to an improved strain-induced hardening of the soft phase. [ABSTRACT FROM AUTHOR]

In order to solve the problems of high THD (total harmonic distortion) of air-gap magnetic density, large cogging torque, and low power density of permanent magnet (PM) hub motor, a built-in tangential and radial PM combined-pole hub motor is proposed in this paper. The magnetic field provided by tangential PM is the main magnetic field, and the magnetic field provided by radial PM plays an auxiliary role in regulation, which can effectively improve the air-gap magnetic density of the motor, reduce the THD of back electromotive force (EMF), and weaken the peak value of cogging torque. Based on the equivalent magnetic circuit method, this paper analyzes the magnetic circuit of the motor, deduces the leakage magnetic flux coefficient, and reduces the leakage magnetic flux by optimizing the structure of the motor. Finally, the prototype is manufactured and tested to verify the effectiveness of finite element analysis. The results show that the designed PM hub drive motor has low THD of back EMF and good sinusoidality of waveform under no-load condition, and good output performance. [ABSTRACT FROM AUTHOR]

The direct finite element method is a type commonly used for nonlinear seismic soil-structure interaction (SSI) analysis. This method introduces a truncated boundary referred to as an artificial boundary meant to divide the soil-structure system into finite and infinite domains. An artificial boundary condition is used on a truncated boundary to achieve seismic input and simulate the wave radiation effect of infinite domain. When the soil layer is particularly thick, especially for a three-dimensional problem, the computational efficiency of seismic SSI analysis is very low due to the large size of the finite element model, which contains an whole thick soil layer. In this paper, an accurate and efficient scheme is developed to solve the nonlinear seismic SSI problem regarding thick soil layers. The process consists of nonlinear site response and SSI analysis. The nonlinear site response analysis is still performed for the whole thick soil layer. The artificial boundary at the bottom of the SSI analysis model is subsequently relocated upward from the bottom of the soil layer (bedrock surface) to the location nearest to the structure as possible. Finally, three types of typical sites and underground structures are adopted with seismic SSI analysis to evaluate the accuracy and efficiency of the proposed efficient analysis scheme. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most common cancer worldwide and its treatment remains a challenge. Effective control of cell survival and proliferation is critical in the prevention of oncogenesis and successful treatment of cancer. Long non-coding RNAs (lncRNAs) have emerged as primary regulators of carcinogenesis. Growth arrest specific 5 (GAS5), a lncRNA, is known to be aberrantly expressed in several types of cancer, however, the role of GAS5 in CRC remains unclear. In the present study, GAS5 mRNA expression was measured in CRC and adjacent normal mucosa tissue samples from 53 patients using reverse transcription-quantitative polymerase chain reaction analysis, in addition to seven CRC cell lines. GAS5 mRNA expression was observed to be markedly downregulated in human CRC tissues and cell lines. Decreased GAS5 expression was associated with an increase in tumor diameter [odds ratio (OR), 0.176 (95% CI, 0.053-0.586); P=0.003] and later tumor-node-metastasis stage [OR, 0.261 (95% CI, 0.083-0.819); P=0.019]. Patients with decreased GAS5 expression exhibited decreased overall survival rates compared with patients with increased GAS5 expression (P=0.015). The Cox proportional hazards model demonstrated that downregulated GAS5 expression was an independent prognostic factor for CRC (hazard ratio, 0.236; 95% confidence interval, 0.067-0.827; P=0.024). Functional assays demonstrated that overexpression of GAS5 inhibited cell proliferation and survival, and induced G0/G1 cell cycle arrest and apoptosis; however, knockdown of GAS5 expression enhanced cell proliferation, and reduced G0/G1 arrest and apoptosis. In conclusion, the results of the present study suggest that GAS5 is essential in the control of apoptosis and cell growth in CRC. Therefore, GAS5 may represent a novel prognostic and diagnostic marker of CRC, in addition to being a potential therapeutic target. [ABSTRACT FROM AUTHOR]

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