Research on Whole‑Process Tensile Behavior of Headed Studs in Steel–Concrete Composite Structures

Liang?Dong Zhuang,Hong?Bing Chen,Yuan Ma,Ran Ding 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.4

The headed studs have been widely applied in steel–concrete composite structures as shear connectors. However, the tensile performance of headed studs is also key to the structural performance in many cases such as the semi-rigid composite joints including steel beam–concrete wall joint and steel column–base joint. Therefore, this study presents experimental and analytical study on the whole-process tensile behavior of headed studs. Tests on a total of 33 pullout specimens are first conducted. The tensile capacity and load–deformation behavior of the anchorage concrete, which dominates the structural performance of headed studs, are thoroughly analyzed. In addition, test data in the literature are collected for quantitatively evaluating the influence of embedment depth, bearing area, boundary conditions, and concrete strength on the tensile behavior of the anchorage concrete. On the basis of the influence evaluation, an analytical model represented by a piecewise function is proposed to describe the whole-process load–deformation behavior of the anchorage concrete and validated through the comparison between the predicted curves and all collected experimental results. Then the proposed model is applied to simulate the rotational behavior of the typical semi-rigid joint anchored by headed studs, which takes the contribution of the anchorage concrete into consideration, and is verified by experimental results. The research findings indicate that tensile behavior of anchorage concrete is crucial to the structural performance of semi-rigid joints, even for headed studs with large embedment depth and bearing area.

The Effects of Electro Slag Welding on Material Properties of Box Column Plates

Cheng-Cheng Chen,Yu-Chen Liang2 한국강구조학회 2011 International Journal of Steel Structures Vol.11 No.2

The effects of electro slag welding (ESW) on the material properties of box column plates, which is ASTM A572 Gr. 50steel, were investigated experimentally and numerically. The material properties of the column plates before and after ESW were evaluated by macro-etching observation, micro-structural observation, and CVN impact tests. The temperature distribution of the column plates, with the ESW heat cycle as the heat input, was simulated by using the ANSYS FEM software. It was found that: (1) The CVN values in the through thickness direction of the base metal can be as low as 14J, 8.1J, and 8.1J at 0oC for plate thicknesses of 32, 40, and 50 mm respectively; (2) During the ESW process, the measured peak temperature for a 25×50 mm column plate surface was as high as 1033, 880 and 744oC for plate thicknesses of 32, 40 and, 50 mm respectively;(3) After the ESW heat cycle, the through thickness CVN value decreased by 68% for the coarse grain heat affected zone (HAZ) of the column pate; (4) The FEM thermal conduction model developed was able to simulate the temperature distribution of the steel plate during the ESW process with reasonable accuracy; (5) To avoid welding penetration due to ESW, a minimum plate thickness is suggested; (6) The impact of ESW heat cycle is more significant for thin column plates compared to thick ones.

Breviscapine Ameliorates Fear Extinction and Anxiety in BALB/cJ Mice

Wei Liang(Wei Liang),Jing Huang(Jing Huang),Shuya Yang(Shuya Yang),Peng Huang(Peng Huang),Jun Chen(Jun Chen),Chen Chen(Chen Chen),Qun Yang(Qun Yang),Fengzhan Li(Fengzhan Li) 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.3

Objective In this research, the influence of breviscapine on anxiety, fear elimination, and aggression and the potential mechanism was investigated. Methods Anxiety and locomotion were analyzed by elevated plus maze and open field test in mice. Bussey-Saksida Mouse Touch Screen Chambers were used to perform fear conditioning. Territorial aggression was assessed by resident intruder test. Protein levels were evaluated by Western blot. Breviscapine improved fear-extinction learning in BALB/cJ mice. Results Breviscapine at 20-100 mg/kg increased center cross number, total distance traveled, and velocity in a dose-dependent manner. On the other hand, breviscapine at 20-100 mg/kg decreased the immobility time in open field test. In addition, breviscapine at 20-100 mg/kg increased the ratio of time on the open arm, time on the distal parts of the open arm, and total distance traveled in elevated plus maze. Breviscapine at 100 mg/kg increased the average attack latency and decreased the number of attacks over the last 3 days of resident intruder test. In hippocampus, protein levels of postsynaptic density protein-95 and synaptophysin were elevated by breviscapine at these three doses. Conclusion The administration of breviscapine alleviates fear extinction, anxiety, and aggression, while increases locomotor in a dose-dependent manner, which might be associated with its influence on synaptic function.

Reports : IGF1 potentiates BMP9-induced osteogenic differentiation in mesenchymal stem cells through the enhancement of BMP/Smad signaling

( Liang Chen ),( Xiang Zou ),( Ran-xi Zhang ),( Chang-jun Pi ),( Nian Wu ),( Liang-jun Yin ),( Zhong-liang Deng ) 생화학분자생물학회(구 한국생화학분자생물학회) 2016 BMB Reports Vol.49 No.2

Engineered bone tissue is thought to be the ideal alternative for bone grafts in the treatment of related bone diseases. BMP9 has been demonstrated as one of the most osteogenic factors, and enhancement of BMP9-induced osteogenesis will greatly accelerate the development of bone tissue engineering. Here, we investigated the effect of insulin-like growth factor 1 (IGF1) on BMP9-induced osteogenic differentiation, and unveiled a possible molecular mechanism underling this process. We found that IGF1 and BMP9 are both detectable in mesenchymal stem cells (MSCs). Exogenous expression of IGF1 potentiates BMP9-induced alkaline phosphatase (ALP), matrix mineralization, and ectopic bone formation. Similarly, IGF1 enhances BMP9-induced endochondral ossification. Mechanistically, we found that IGF1 increases BMP9-induced activation of BMP/Smad signaling in MSCs. Our findings demonstrate that IGF1 can enhance BMP9-induced osteogenic differentiation in MSCs, and that this effect may be mediated by the enhancement of the BMP/Smad signaling transduction triggered by BMP9. [BMB Reports 2016; 49(2): 122-127]

SDC4 Gene Silencing Favors Human Papillary Thyroid Carcinoma Cell Apoptosis and Inhibits Epithelial Mesenchymal Transition via Wnt/β-Catenin Pathway

Liang-Liang Chen,Ge-Xin Gao,Fei-Xia Shen,Xiong Chen,Xiao-Hua Gong,Wen-Jun Wu 한국분자세포생물학회 2018 Molecules and cells Vol.41 No.9

As the most common type of endocrine malignancy, papillary thyroid cancer (PTC) accounts for 85-90% of all thyroid cancers. In this study, we presented the hypothesis that SDC4 gene silencing could effectively attenuate epithelial mesenchymal transition (EMT), and promote cell apoptosis via the Wnt/β-catenin signaling pathway in human PTC cells. Bioinformatics methods were employed to screen the determined differential expression levels of SDC4 in PTC and adjacent normal samples. PTC tissues and adjacent normal tissues were prepared and their respective levels of SDC4 protein positive expression, in addition to the mRNA and protein levels of SDC4, Wnt/β-catenin signaling pathway, EMT and apoptosis related genes were all detected accordingly. Flow cytometry was applied in order to detect cell cycle entry and apoptosis. Finally, analyses of PTC migration and invasion abilities were assessed by using a Transwell assay and scratch test. In PTC tissues, activated Wnt/β-catenin signaling pathway, increased EMT and repressed cell apoptosis were determined. Moreover, the PTC K1 and TPC-1 cell lines exhibiting the highest SDC4 expression were selected for further experiments. In vitro experiments revealed that SDC4 gene silencing could suppress cell migration, invasion and EMT, while acting to promote the apoptosis of PTC cells by inhibiting the activation of the Wnt/β-catenin signaling pathway. Besides, si-β-catenin was observed to inhibit the promotion of PTC cell migration and invasion caused by SDC4 overexpression. Our study revealed that SDC4 gene silencing represses EMT, and enhances cell apoptosis by suppressing the activation of the Wnt/β-catenin signaling pathway in human PTC.

Transparent conducting oxide glass grown with TiO2-nanotube array for dye-sensitized solar cell

Chen-Hon Chen,Keh-Chang Chen,Ju-Liang He 한국물리학회 2010 Current Applied Physics Vol.10 No.2

An arc ion plating (AIP) deposition system was employed to produce metal titanium layer on transparent conducting oxide glass, and followed by anodically oxidizing to form a TiO2-nanotube array electrode. A dye-sensitized solar cell (DSC) was then assembled as ITO glass/[TiO2-nanotube (N3 dye)]/I2 + LiI electrolyte/Pt/ITO glass. Anodizing bath composition was varied, and post-annealing was carried out. Consequent changes in the TiO2-nanotube array microstructure and photovoltaic efficiency of the assembled DSC device were revealed. Experimental results show that a 5-lm thick metal titanium layer can be obtained after 45 min AIP deposition. The metal titanium layer underwent complete conversion into XRD-amorphous TiO2-nanotube array after anodic oxidation for 2 h. The tube can reach 10.7 ㎛ long with tube inner diameter 92 nm. The ammonium fluoride in the anodizing bath accelerates the tube growth rate. Thermal annealing at temperatures over 250 ℃ works best on anatase crystallization of the TiO2-nanotube. An ultimate photovoltaic efficiency 1.88% (active area 1 ㎠) of the assembled DSC device can be obtained for the TiO2-nanotube grown ITO glass annealed at 350 ℃.

SDC4 Gene Silencing Favors Human Papillary Thyroid Carcinoma Cell Apoptosis and Inhibits Epithelial Mesenchymal Transition via Wnt/β-Catenin Pathway

Chen, Liang-Liang,Gao, Ge-Xin,Shen, Fei-Xia,Chen, Xiong,Gong, Xiao-Hua,Wu, Wen-Jun Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.9

As the most common type of endocrine malignancy, papillary thyroid cancer (PTC) accounts for 85-90% of all thyroid cancers. In this study, we presented the hypothesis that SDC4 gene silencing could effectively attenuate epithelial mesenchymal transition (EMT), and promote cell apoptosis via the $Wnt/{\beta}-catenin$ signaling pathway in human PTC cells. Bioinformatics methods were employed to screen the determined differential expression levels of SDC4 in PTC and adjacent normal samples. PTC tissues and adjacent normal tissues were prepared and their respective levels of SDC4 protein positive expression, in addition to the mRNA and protein levels of SDC4, $Wnt/{\beta}-catenin$ signaling pathway, EMT and apoptosis related genes were all detected accordingly. Flow cytometry was applied in order to detect cell cycle entry and apoptosis. Finally, analyses of PTC migration and invasion abilities were assessed by using a Transwell assay and scratch test. In PTC tissues, activated $Wnt/{\beta}-catenin$ signaling pathway, increased EMT and repressed cell apoptosis were determined. Moreover, the PTC K1 and TPC-1 cell lines exhibiting the highest SDC4 expression were selected for further experiments. In vitro experiments revealed that SDC4 gene silencing could suppress cell migration, invasion and EMT, while acting to promote the apoptosis of PTC cells by inhibiting the activation of the $Wnt/{\beta}-catenin$ signaling pathway. Besides, $si-{\beta}-catenin$ was observed to inhibit the promotion of PTC cell migration and invasion caused by SDC4 overexpression. Our study revealed that SDC4 gene silencing represses EMT, and enhances cell apoptosis by suppressing the activation of the $Wnt/{\beta}-catenin$ signaling pathway in human PTC.

Magnetic Flux Leakage Image Enhancement using Bidimensional Empirical Mode Decomposition with Wavelet Transform Method in Oil Pipeline Nondestructive Evaluation

Liang Chen,Jingcheng Li,Yakai Zeng,Yongqiang Chen,Wei Liang 한국자기학회 2019 Journal of Magnetics Vol.24 No.3

The magnetic flux leakage (MFL) method is the most widely used and cost-effective inspection technique for oil pipeline. However, noise is inevitable in the process of data collection; thus, the image enhancement method can be more intuitive to identify the defects in an oil pipeline MFL inspection. In this paper, the bidimensional empirical mode decomposition (BEMD) method has been used to study oil pipeline MFL images. The MFL image is decomposed into a finite number of two-dimensional intrinsic mode functions (BIMF) and a residual component by the BEMD. The wavelet transform (WT) was used to remove the noise in the BIMF. The image was then reconstructed by retaining the basic information and removing the noise. The results show that the noise is effectively removed and the detail of the MFL image is well preserved. Thus, the BEMD with WT method for oil pipeline MFL image enhancement is better than the mean filtering method and the WT method.

Study of the Band-gap Structure of a 1D-photonic Crystal by Using Different Numerical Approaches

Liang-Yao Chen,Jian-Bo Chen,Yue-Rui Chen,Yan Shen,Wei-Xi Zhou,Jiu-Chun Ren,Yu-Xiang Zheng 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.4

Comparative studies between the transfer matrices method (TMM) and plane wave method (PWM) approaches have been performed on 1D photonics crystal under different conditions to show the differences between these two kinds of calculations. TMM is suitable for the design of 1D photonic crystal device with high precision and is in good agreement with experimental results, but is not suitable for the 2D and 3D photonic structures which are limited by the complicated boundary conditions at micro interfaces. The result based on the PWM approach to deal approximately with the photonic structure in approximation has not yet been strictly verified by experiment, not even for 1D photonic crystal structures. More efforts will be required to explore its validation under all physical conditions to enhance its application.

Gastrodia elata Bl. Attenuated Learning Deficits Induced by Forced-Swimming Stress in the Inhibitory Avoidance Task and Morris Water Maze

Pei-Ju Chen,Keng-Chen Liang,Hui-Chen Lin,Ching-Liang Hsieh,Kuan-Pin Su,Mei-Chu Hung,Lee-Yan Sheen 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.6

This study adopted the forced-swimming paradigm to induce depressive symptoms in rats and evaluated the effects on learning and memory processing. Furthermore, the effects of the water extract of Gastrodia elata Bl., a well-known Chinese traditional medicine, on amnesia in rats subjected to the forced-swimming procedure were studied. Rats were subjected to the forced-swimming procedure, and the inhibitory avoidance task and Morris water maze were used to assess learning and memory performance. The acquisition of the two tasks was mostly impaired after the 15-minute forced-swimming procedure. Administration of the water extract of G. elata Bl. for 21 consecutive days at a dosage of 0.5 or 1.0 g/kg of body weight significantly improved retention in the inhibitory avoidance test, and the lower dose showed a better effect than the higher one and the antidepressant fluoxetine (18 mg/kg of body weight). In the Morris water maze, the lower dose of the water extract of G. elata Bl. significantly improved retention by shortening escape latency in the first test session and increasing the time in searching the target zone during the probe test. These findings suggest that water extracts of G. elata Bl. ameliorate the learning and memory deficits induced by forced swimming.