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Automatic concrete spalling detection has become an important issue for metro tunnel examinations and maintenance. This paper focuses on concrete spalling detection research with surface roughness analysis based on point clouds produced by 3D mobile laser scanning (MLS) system. In the proposed method, at first, the points on ancillary facilities attached to tunnel surface are considered as outliers and removed via circular scan-line fitting and large residual error filtering. Then, a roughness descriptor for the metro tunnel surface is designed based on the triangulated grid derived from point clouds. The roughness descriptor is generally defined as the ratio of surface area to the projected area for a unit, which works well in identifying high rough areas on the tunnel surface, such as bolt holes, segment seams, and spalling patches. Finally, rough area classification based on Hough transformation and similarity analysis is performed on the identified areas to accurately label patches belonging to segment seams and bolt holes. After removing the patches of bolt holes and segment seams, the remaining patches are considered as belonging to concrete spalling. The experiment was conducted on a real tunnel interval in Shanghai. The result of concrete spalling detection revealed the validity and feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

The house property tax pilot policy (HPTPP) introduced in 2011 has resulted in the redistribution of R&D resources. However, few studies have focused on the impacts of this policy. In this paper, we use the heterogeneous stochastic frontier analysis method to measure the R&D total factor productivity (TFP) growth rate of Chinese universities. Then, the difference-in-differences (DID) method is employed to examine the impact of the HPTPP on R&D performance. Furthermore, a series of robustness tests are conducted on the estimated results, including: a parallel trend test, by advancing the introduced time of policy; a reduction of the self-selection bias, by adopting the propensity score matching (PSM); and an interference elimination of the house-purchasing restriction policy. Finally, based on the extensive margin and the intensive margin, we investigate the mechanisms of the HPTPP on R&D performance. The results show that the R&D TFP of Chinese universities displays a downward trend. After reducing self-selection bias, the HPTPP exerts no significant effect on R&D TFP growth rate of Shanghai's universities, but the HPTPP does reduce the R&D TFP growth rate of universities located in Chongqing. This conclusion remains robust after changing the matching ratio of the PSM strategy and eliminating the interference of the house-purchasing restriction policy. For Shanghai's universities, the effects of the HPTPP on extensive margin (i.e., factor input scale) and intensive margin (quantity of efficient factors) are not clear, resulting in an uncertain impact on R&D TFP growth rate. However, for Chongqing, the negative effect on the scale of factor input leads to a decline in R&D TFP growth rate of universities. Therefore, when restraining housing prices, the government should prevent the negative effect on R&D investment and attract high-end talent through preferential conditions. • We use the heterogeneous SFA method to calculate the R&D TFP. • We explore the effect of the HPTPP on R&D performance of universities. • We conduct a series of robustness tests and investigate the influential mechanism. • The HPTPP exerts no effect on R&D TFP in Shanghai but reduce R&D TTP in Chongqing. • The HPTPP reduce the R&D capital input of Chongqing's universities. [ABSTRACT FROM AUTHOR]

This study applies the concentration-index methodology to adult respondents of a unique household survey recently conducted in Shanghai to quantify income-related inequality in self-assessed health status and its avoidable component. Clustered random sampling was used to produce a citywide representative sample. A continuous measure of latent health was generated based on the predicted values from an ordinal probit model with the categorical response of self-assessed health status as the dependent variable. The concentration index is estimated as 0.06 and the percentage of its avoidable component is roughly 72 percent. Hence there is room for social welfare programs to intervene and reduce income-related health inequalities in Shanghai. [ABSTRACT FROM AUTHOR]

PURPOSE: To identify the vascular endothelial growth factor receptors (VEGFRs) expression in the rabbit synoviums with temporomandibular joint (TMJ) internal derangement (ID). METHODS: Real-time PCR was used to detect VEGF receptor expression in synovium, after establishing the rabbit TMJ ID model for 1, 2, 3, or 4 weeks. VEGFRs mRNA expression was normalized by comparing VEGFRs mRNA with internal control GAPDH. SPSS13.0 software package was used for comparison of the differences between the two groups. RESULTS: In the first and fourth week, significant difference was observed in VEGFR-2 mRNA expression between the experimental group and control group; however, no statistical difference was found in VEGFR-1 and VEGFR-3 mRNA expression between the experimental group and control group. In the second and third week, there were no statistical differences in VEGFR-1, VEGFR-2, and VEGFR-3 mRNA expression between the experimental group and control group. CONCLUSION: VEGFR-2 may play an important role in TMJ ID and adhesion formation. Specific VEGFR-2 inhibitors may be used to prevent adhesion formation in TMJ ID. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (Grant No. 08DZ2271100), Grant of Shanghai Leading Academic Discipline Project (Grant No.S30206), Grant of Shanghai Municipal Bureau of Health (Grant No.2008160), Grant from Shanghai "Phosphor" Science Foundation (Grant No.04QMH1415), Grant from Ph.D. Creative Foundation of Shanghai Jiao Tong University School of Medicine (Grant No.BXJ0926), and Research Fund of Medicine and Engineering of Shanghai Jiao Tong University (Grant No.YG2009MS42). [ABSTRACT FROM AUTHOR]