Experimental and analytical study on continuous GFRP concrete decks with steel bars

Zhaojie Tong,Yiyan Chen,Qiao Huang,Xiaodong Song,Bingqing Luo,Xiang Xu 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.6

A hybrid bridge deck is proposed, which includes steel bars, concrete and glass-fiber-reinforced-polymer (GFRP) plates with channel sections. The steel bar in the negative moment region can increase the flexural stiffness, improve the ductility, and reduce the GFRP ratio. Three continuous decks with different steel bar ratios and a simply supported deck were fabricated and tested to study the mechanical performance. The failure mode, deflection, strain distribution, cracks and support reaction were tested and discussed. The steel bar improves the mechanical performance of continuous decks, and a theoretical method is proposed to predict the deformation and the shear capacity. The experimental results show that all specimens failed with shear failure in the positive moment region. The increase of steel bar ratio in the negative moment region can achieve an enhancement in the flexural stiffness and reduce the deflection without increasing GFRP. Moreover, the continuous deck can achieve a yield load, and the negative moment can be carried by GFRP plates after the steel bar yields. Finally, a nonlinear analytical method for the deflection calculation was proposed and verified, with considering the moment redistribution, non-cracked sections and nonlinearity of material. In addition, a simplified calculation method was proposed to predict the shear capacity of GFRP-concrete decks.

A hierarchical semantic segmentation framework for computer vision-based bridge damage detection

Jingxiao Liu,Yujie Wei,Bingqing Chen,Hae Young Noh 국제구조공학회 2023 Smart Structures and Systems, An International Jou Vol.31 No.4

Computer vision-based damage detection enables non-contact, efficient and low-cost bridge health monitoring, which reduces the need for labor-intensive manual inspection or that for a large number of on-site sensing instruments. By leveraging recent semantic segmentation approaches, we can detect regions of critical structural components and identify damages at pixel level on images. However, existing methods perform poorly when detecting small and thin damages (e.g., cracks); the problem is exacerbated by imbalanced samples. To this end, we incorporate domain knowledge to introduce a hierarchical semantic segmentation framework that imposes a hierarchical semantic relationship between component categories and damage types. For instance, certain types of concrete cracks are only present on bridge columns, and therefore the noncolumn region may be masked out when detecting such damages. In this way, the damage detection model focuses on extracting features from relevant structural components and avoid those from irrelevant regions. We also utilize multi-scale augmentation to preserve contextual information of each image, without losing the ability to handle small and/or thin damages. In addition, our framework employs an importance sampling, where images with rare components are sampled more often, to address sample imbalance. We evaluated our framework on a public synthetic dataset that consists of 2,000 railway bridges. Our framework achieves a 0.836 mean intersection over union (IoU) for structural component segmentation and a 0.483 mean IoU for damage segmentation. Our results have in total 5% and 18% improvements for the structural component segmentation and damage segmentation tasks, respectively, compared to the best-performing baseline model.

The Aurora Kinase Inhibitor CYC116 Promotes the Maturation of Cardiomyocytes Derived from Human Pluripotent Stem Cells

Xin Xie,Wanzhi Tu,Chenwen Huang,Ziyang Chen,Xinyue Ren,Bingqing He,Xiaoyan Ding,Yuelei Chen,Xin Xie 한국분자세포생물학회 2022 Molecules and cells Vol.45 No.12

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in applications such as regenerative medicine, cardiac disease modeling, and in vitro drug evaluation. However, hPSC-CMs are immature, which limits their applications. During development, the maturation of CMs is accompanied by a decline in their proliferative capacity. This phenomenon suggests that regulating the cell cycle may facilitate the maturation of hPSC-CMs. Aurora kinases are essential kinases that regulate the cell cycle, the role of which is not well studied in hPSC-CM maturation. Here, we demonstrate that CYC116, an inhibitor of Aurora kinases, significantly promotes the maturation of CMs derived from both human embryonic stem cells (H1 and H9) and iPSCs (induced PSCs) (UC013), resulting in increased expression of genes related to cardiomyocyte function, better organization of the sarcomere, increased sarcomere length, increased number of mitochondria, and enhanced physiological function of the cells. In addition, a number of other Aurora kinase inhibitors have also been found to promote the maturation of hPSC-CMs. Our data suggest that blocking aurora kinase activity and regulating cell cycle progression may promote the maturation of hPSC-CMs.

The Aurora Kinase Inhibitor CYC116 Promotes the Maturation of Cardiomyocytes Derived from Human Pluripotent Stem Cells

Xin Xie,Wanzhi Tu,Chenwen Huang,Ziyang Chen,Xinyue Ren,Bingqing He,Xiaoyan Ding,Yuelei Chen,Xin Xie 한국분자세포생물학회 2022 Molecules and cells Vol.45 No.12

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in applications such as regenerative medicine, cardiac disease modeling, and in vitro drug evaluation. However, hPSC-CMs are immature, which limits their applications. During development, the maturation of CMs is accompanied by a decline in their proliferative capacity. This phenomenon suggests that regulating the cell cycle may facilitate the maturation of hPSC-CMs. Aurora kinases are essential kinases that regulate the cell cycle, the role of which is not well studied in hPSC-CM maturation. Here, we demonstrate that CYC116, an inhibitor of Aurora kinases, significantly promotes the maturation of CMs derived from both human embryonic stem cells (H1 and H9) and iPSCs (induced PSCs) (UC013), resulting in increased expression of genes related to cardiomyocyte function, better organization of the sarcomere, increased sarcomere length, increased number of mitochondria, and enhanced physiological function of the cells. In addition, a number of other Aurora kinase inhibitors have also been found to promote the maturation of hPSC-CMs. Our data suggest that blocking aurora kinase activity and regulating cell cycle progression may promote the maturation of hPSC-CMs.

Assessment of clinical competency among TCM medical students using standardized patients of traditional Chinese medicine: A 5-year prospective randomized study

Zeng Jinhao,Liang Shuang,Zhang Xiaotong,Yan Ran,Chen Chongli,Wen Lijuan,Xia Ting,Li Wenyuan,Lu Bingqing,Nian Qing,Yang Han,Guo Jing 한국한의학연구원 2022 Integrative Medicine Research Vol.11 No.2

Background: Some Western medicine schools in China established standardized patient (SP) programs for medical education. However, SP programs are rarely applied to the education of traditional Chinese medicine (TCM). In this study, we evaluated the effectiveness of using standardized patient traditional Chinese medicine (SP-TCM) to improve clinical competency among TCM medical students. Methods: This study was a prospective, 2-group, parallel-training randomized trial over the course of 5 years. Data were collected from September 2016 to December 2020. Participants in each year were randomly allocated into the traditional-method training group or the SP-TCM training group (1:1) for a 3-month curriculum. Measurement of clinical competency among all trainees was based on a standardized examination composed of scores of medical record documentation, scores of TCM syndrome differentiation and therapeutic regimen, and checklist assessment from both SP-TCMs and TCM professionals. Feedback was collected using semi-constructive questionnaires from both groups. Results: Compared with those assigned to traditional-method training, those assigned to SP-TCM training demonstrated significantly greater post-training improvement in medical record documentation and TCM syndrome differentiation and therapeutic regimen. Moreover, SP-TCM trainees outscored those assigned to traditional training in the assessment for encounter performance given by independent SP-TCMs and TCM professionals. The SP-TCM method gained higher satisfaction of training efficacy and test performance than the traditional method. Conclusion: This SP-TCM program demonstrated great benefits for improving clinical competency among TCM medical students.