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Data-driven methods have now been widely used in structural health monitoring of civil infrastructures thanks to the rapid development of sensor technologies with massive structural and operational condition data. One main issue of data-driven methods is that the computational time increases with the number of monitoring data used, which limits their applications for online structural condition assessment. Focusing on bridge structural health monitoring, this paper proposes a representative data selection strategy for online performance assessment based on Gaussian process models. The proposed method can effectively reduce the required monitoring data size for training, allowing the bridge performance assessment to be conducted in a real-time manner. The method is developed in a probabilistic manner, allowing associated uncertainty of bridge monitoring data to be rigorously considered. A probabilistic warning index is proposed for bridge condition assessment and anomaly detection. The proposed method is validated using synthetic data and applied to structural condition assessment of two full-scale bridges, illustrating the feasibility for real implementations. [ABSTRACT FROM AUTHOR]

We retrospectively evaluated the clinical outcome of penile prosthesis implantation (PPI) in Chinese patients with severe erectile dysfunction (SED). From July 2000 to December 2011, 224 patients (mean age: 35.9±11.8 years, range: 20-75 years) with SED underwent PPI by experienced surgeon according to standard PPI procedure at our centre. A malleable prosthesis (AMS 650) was implanted in 45 cases (20.1%), and a three-piece inflatable prosthesis (AMS 700 CXM or AMS 700 CXR) was implanted in 179 cases (79.9%). Surgical outcomes, including postoperative complications, clinical efficacy and couple satisfaction, were evaluated over than 6 months postoperatively using medical record abstraction, IIEF-5, quality of life (QoL) scores, and the patient/partner sexual satisfaction score proposed by Bhojwani et al. Of the 224 patients eligible for the study, 201 subjects (89.7%) completed follow-up. All of patients could perform sexual intercourse post PPI with the mean postoperative IIEF-5 and QoL scores were 20.02±2.32 and 5.28±0.76, respectively, which were significantly improved compared with the preoperative scores (6.29±1.5 and 2.13±0.84, P

Resonant metamaterials have attracted significant research interest in mechanical and acoustic engineering with applications in the fields of sound and vibration control thanks to their integrated tuned mass dampers. One prevailing issue regarding industrial application of such structures is the high probability of local damage for their resonating parts. Accurate and efficient health state estimation methods for resonant metamaterials are therefore urgently required. In particular, the quantification and localization of damaged resonators represent key pieces of information for the operator of a structural asset. This work presents for the first time an investigation into quantifying and identifying damaged oscillators in a resonant metamaterial based on the measured frequency response function (FRF) data. Both data-driven and physics-based methods are implemented and corresponding results are exhibited. Manufacturing-induced structural uncertainty is quantified through physical measurements and taken into account in this work. It is demonstrated that such uncertainty may have a rather significant impact on the response of 3D printed resonant metamaterials, leading to difficulties vis-a-vis damage quantification. The proposed theoretical developments are able to properly account for such uncertainties, providing probabilistic estimation indices for the existing damage level and location. Both simulated and experimental case studies are presented to validate the two proposed methodologies and comparisons are also exhibited and discussed. [ABSTRACT FROM AUTHOR]

Photodegradation of pollutions by TiO2 under irradiation of weak UV and visible lights was one of the key points to expand the application of heterogeneous photocatalysis. Based on the adsorption phase synthesis, N doping and co-doping with N and Fe2O3 were employed to prepare TiO2 multi composite photocatalysts. The activity of these photocatalyts was evaluated by photodegradation of methyl-orange illuminated under weak UV and visible lights. Via UV-Vis diffuse reflectance spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and photoluminescence spectra, the effects on the light absorption and visible response expansion of catalysts caused by different conditions were explored, such as sintering temperature, doping content of N and co-doping. Followed that, the changes in the photocatalytic activities were studied under the irradiation of weak light. The results showed that, N doping could enhance the light absorption of the catalysts, thus significantly enhanced their photocatalytic activity illuminated under UV weak light. All N-doped photocatalysts had a higher activity than the commercial available P25 photocatalyst. The visible response of catalysts was expanded little caused by N doping, thereby most catalysts doped by single N element had no activity illuminated by weak visible light. Only the catalyst doped with 5% of N element showed a weak activity after calcined at 900 degrees C . Due to the synergy effects between N doping and Fe2O3 coupling, co-doping did not only enhance the light absorption of the catalysts, but also significantly expanded the visible response of catalysts. So, co-doped catalysts showed a good catalytic activity when excited by weak visible light.

Objective: To discuss the necessity of prophylactic contralateral nephroureterectomy in renal transplantation patients with upper urinary tract transitional cell carcinoma (TCC)., Methods: In our study 15 renal transplantation patients with upper urinary tract TCC were involved from Dec.2006 to May 2013. All the patients received prophylactic contralateral nephroureterectomy 3 months after their last nephroureterectomy. A retrospective analysis was performed., Results: TCC of upper urinary tract was confirmed by postoperative pathology in all the 15 cases .Similarly, TCC of contralateral upper urinary tract was detected in 7 of these cases (46.7%), and 13 survived after 36 months' follow-up (86.7%)., Conclusion: In the renal transplantation patient with unilateral upper urinary tract TCC, the possibility of contralateral upper urinary tract TCC is high, thus the necessity of prophylactic contratateral nephroureterectomy is certain.

Objective: To investigate the clinical efficacy and patient and partner's satisfaction with penile prosthesis implantation (PPI) for treating Chinese patients with severe erectile dysfunction (SED)., Methods: One hundred and sixty-eight SED patients were successfully treated by PPI from July 2000 to June 2010. Of the 146 (86.9%) patients who had been followed up over 6 months post-operation, 36 (24.7%) had been implanted with one piece malleable prosthesis (AMS650) and 110 (75.3%) with three piece inflatable prosthesis (AMS700CXM).All the patients had been followed up by using international index of erectile dysfunction (IIEF5), Quality of Life Score (QOL) for evaluating clinical efficacy and using Visual Analogue Scale (VAS) for evaluating patient and partner's satisfaction and the duration of the follow-up was 6 to 119 months., Results: The mean age of patients was 35.9+/-12.1 years(20 to 75 years), All the operations were successful and sexual intercourse with PPI was performed post 4 to 6 weeks without severe complications like infection and erosion. The prosthesis survive rate and frequent sexual intercourse rate were 98.6% and 87.7% respectively. IIEF5 scores pre and post PPI were 6.3+/- 1.7 and 21.3+/-1.6 respectively,the QOL scores pre and post PPI were 5.1+/-0.9 and 1.5+/-0.5 respectively, and both of them showed significant improvement (P<0.01). As for VAS, the patient and partner's overall satisfaction rates were 92.5% and 90.4% respectively. Moreover, better satisfaction was showed with AMS700CXM as compared with AMS650 (P<0.05) in patients with SED., Conclusion: PPI is the safe and effective treatment option for Chinese patients with SED. The AMS700CXM penile prosthesis is better than AMS650 for patients' overall satisfaction.