Integrated Simulation and Experimental Test of the Residual Stress Field for Large-sized Straight Welded Pipe Processed with JCOE Technology

Junting Luo,Yahong Xue,Ke Chen,Yanpeng Shang,Chunxiang Zhang 한국강구조학회 2017 International Journal of Steel Structures Vol.17 No.1

Continuous integrated simulation of JCO forming, reducing gap, welding, and mechanical expanding processes of large-sized straight welded pipe is conducted using Marc software. Taking expanding ratio as variable, the residual stress distribution of weld bead and the influence rule of the expanding ratio are investigated before and after expansion. In thickness direction, in the bonding zone of pre-welding and outside weld, as well as at the bottom of the inside weld, the residual stress is large before expanding. The residual stress in the outside weld is large after expanding. The peak value of residual stress is decreased by about 61 to 78%. The expanding ratio is higher, the peak clipping effect becomes more evident, and residual stress becomes more uniform. The simulation results agrees with the test results, thus confirm that integrated simulation can achieve the visualization of residual stress evolution in the production process of large-sized straight welded pipe.

Cluster Analysis on Research Front of Climate Change and International Trade

Chen Yongguo,Yan Junting 한중경제문화학회 2020 한중경제문화연구 Vol.15 No.-

MicroRNA-186 targets SKP2 to induce p27^Kip1-mediated pituitary tumor cell cycle deregulation and modulate cell proliferation

He, Zongze,Chen, Longyi,Wang, Qi,Yin, Cheng,Hu, Junting,Hu, Xiao,Fei, Fan,Tang, Jian The Korean Society of Pharmacology 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.3

Pituitary tumors are usually benign but can occasionally exhibit hormonal and proliferative behaviors. Dysregulation of the G1/S restriction point largely contributes to the over-proliferation of pituitary tumor cells. F-box protein S-phase kinase-interacting protein-2 (SKP2) reportedly targets and inhibits the expression of $p27^{Kip1}$, a well-known negative regulator of G1 cell cycle progression. In this study, SKP2 expression was found to be upregulated while $p27^{Kip1}$ expression was determined to be downregulated in rat and human pituitary tumor cells. Furthermore, SKP2 knockdown induced upregulation of $p27^{Kip1}$ and cell growth inhibition in rat and human pituitary tumor cells, while SKP2overexpression elicited opposite effects on $p27^{Kip1}$ expression and cell growth. The expression of microRNA-186 (miR-186) was reported to be reduced in pituitary tumors. Online tools predicted SKP2 to be a direct downstream target of miR-186, which was further confirmed by luciferase reporter gene assays. Moreover, miR-186 could modulate the cell proliferation and $p27^{Kip1}$-mediated cell cycle alternation of rat and human pituitary tumor cells through SKP2. As further confirmation of these findings, miR-186 and $p27^{Kip1}$ expression were downregulated, while SKP2 expression was upregulated in human pituitary tumor tissue samples; thus, SKP2 expression negatively correlated with miR-186 and $p27^{Kip1}$ expression. In contrast, miR-186 expression positively associated with $p27^{Kip1}$ expression. Taken together, we discovered a novel mechanism by which miR-186/SKP2 axis modulates pituitary tumor cell proliferation through $p27^{Kip1}$-mediated cell cycle alternation.

Short-term Power Load Forecasting Based on Phase Space Reconstruction and EMD-ELM

Zou Hongbo,Yang Qinhe,Chen Junting,Chai Yanhui 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

With the increasing complexity of the world energy structure, the uncertainty of the power system increases significantly, and the accuracy of the short-term power load forecasting is of great significance to the safe, economical and reliable operation of the power system. In order to further improve the accuracy of short-term power load forecasting, this paper innovatively combines the theories such as phase space reconstruction, empirical mode decomposition, and extreme learning machine to establish a new short-term power load forecasting model based on phase space reconstruction and EMD-ELM. The prediction results show that the root means square error, average relative error and global maximum relative error of the short-term power load forecasting model based on phase space reconstruction and EMD-ELM are much smaller than other forecasting models, which verifies the correctness and effectiveness of the short-term load forecasting method.

Finite Element Analysis on the Mechanical Properties of Self-lubricating Fabric Liners Based on Periodic Boundary Conditions

Yahong Xue,Jigang Chen,Xin Shi,Jichuan Yao,Junting Luo 한국섬유공학회 2018 Fibers and polymers Vol.19 No.3

A new parameterized finite element model was established for self-lubricating fabric liners in different weaving patterns. This model precisely simulated the spatial configuration of woven yarns with consideration of the cross-section deformation as well as the anisotropic material characteristics of yarns by converting the principal material direction along the yarn-path. Moreover, a set of simple and universal periodic boundary equations was proposed to solve the problem of the overabundance restriction in the boundary surfaces. To verify the validation of the finite element method proposed in this paper, an experimental prediction on elastic constants of self-lubricating fabric liners was carried out. The results indicate that the finite element model can successfully predict the macro mechanical properties of self-lubricating fabric liners with periodical structures. Based on the finite element model, the distributions of stress and strain, as well as the effects of weaving type and weaving density on the elastic modulus of fabric liners were investigated in details.

MicroRNA-186 targets SKP2 to induce p27Kip1-mediated pituitary tumor cell cycle deregulation and modulate cell proliferation

Zongze He,Longyi Chen,Qi Wang,Cheng Yin,Junting Hu,Xiao Hu,Fan Fei,Jian Tang 대한약리학회 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.3

Pituitary tumors are usually benign but can occasionally exhibit hormonal and proliferative behaviors. Dysregulation of the G1/S restriction point largely contributes to the over-proliferation of pituitary tumor cells. F-box protein S-phase kinase-interacting protein-2 (SKP2) reportedly targets and inhibits the expression of p27Kip1, a well-known negative regulator of G1 cell cycle progression. In this study, SKP2 expression was found to be upregulated while p27Kip1 expression was determined to be downregulated in rat and human pituitary tumor cells. Furthermore, SKP2 knockdown induced upregulation of p27Kip1 and cell growth inhibition in rat and human pituitary tumor cells, while SKP2overexpression elicited opposite effects on p27Kip1 expression and cell growth. The expression of microRNA-186 (miR-186) was reported to be reduced in pituitary tumors. Online tools predicted SKP2 to be a direct downstream target of miR-186, which was further confirmed by luciferase reporter gene assays. Moreover, miR-186 could modulate the cell proliferation and p27Kip1-mediated cell cycle alternation of rat and human pituitary tumor cells through SKP2. As further confirmation of these findings, miR-186 and p27Kip1 expression were downregulated, while SKP2 expression was upregulated in human pituitary tumor tissue samples; thus, SKP2 expression negatively correlated with miR-186 and p27Kip1 expression. In contrast, miR-186 expression positively associated with p27Kip1 expression. Taken together, we discovered a novel mechanism by which miR-186/SKP2 axis modulates pituitary tumor cell proliferation through p27Kip1-mediated cell cycle alternation.

Fertility and prognosis assessment between bleomycin/etoposide/cisplatin and paclitaxel/carboplatin chemotherapy regimens in the conservative treatment of malignant ovarian germ cell tumors: a multicenter and retrospective study

Ran Chu,Penglin Liu,Jingying Chen,Xiaodong Cheng,Kezhen Li,Yanci Che,Jianliu Wang,Li Li,Xi Zhang,Shu Yao,Li Song,Ying Zhao,Changzhen Huang,Ying Xue,Xiyu Pan,Junting Li,Zhongshao Chen,Jie Jiang,Beihua 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.2

Objective: To evaluate the impact of bleomycin/etoposide/cisplatin (BEP) and paclitaxel/carboplatin (PC) chemotherapy regimens on the fertility and prognostic outcomes in malignant ovarian germ cell tumor (MOGCT) patients who underwent fertility-sparing surgery (FSS). Methods: A propensity score matching algorithm was performed between the BEP and PC groups. The χ2 test and the Kaplan-Meier method were used to compare the fertility outcome, disease-free survival (DFS) and overall survival (OS). The Cox proportional hazards regression analysis was used to identify risk factor of DFS. Results: We included 213 patients, 185 (86.9%) underwent BEP chemotherapy, and 28 (13.1%) underwent PC chemotherapy. The median age was 22 years (range, 8–44 years), and the median follow-up period was 63 months (range, 2–191 months). Fifty-one (29.3%) patients had a pregnancy plan, and 35 (85.4%) delivered successfully. In the before and after propensity score matching cohorts, there were no significant differences in spontaneous abortion, selective termination of pregnancy, during-pregnancy status, and live birth between the BEP and PC groups (p>0.05). Fourteen (6.6%) patients experienced recurrence, including 11 (5.9%) in the BEP group and 3 (10.7%) in the PC group. Four (1.9%) patients in the BEP group died. Kaplan-Meier analysis revealed no significant differences in DFS (p=0.328) and OS (p=0.446) between the BEP and PC groups, and the same survival results were observed in the after matching cohort. Conclusion: The PC regimen is as safe as the BEP regimen for MOGCT patients with fertility preservation treatment, and no differences were observed in fertility and clinical prognosis.

Epitaxial growth of <010>-oriented MoO2 nanorods on m-sapphire

Jinxin Liu,Jiao Shi,Di Wu,Xiaoming Zheng,Fengming Chen,Junting Xiao,Youzhen Li,Fei Song,Yongli Gao,Han Huang 한국물리학회 2020 Current Applied Physics Vol.20 No.10

Molybdenum dioxide (MoO2) materials have attracted considerable interests due to their superduper properties and potential applications, relating to the growth directions and exposed surfaces. Here, we reported as the substrate changes from c-to m-sapphire, the growth direction of epitaxial MoO2 nanorods via an atmospheric pressure chemical vapor deposition approach changes along from <001> to <010> of bulk monoclinic MoO2 accompanied by exposing different surfaces. Optical microscopy (OM), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cross-sectional scanning electron microscopy (SEM), highresolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) measurements reveal these MoO2 nanorods are epitaxially grown on m-sapphire substrates with the orientation of MoO2 (101)//sapphire (1010) and MoO2 <010> in line with sapphire <0001>. The electrical conductivity significantly depends on the crystallographic direction of MoO2 nanorods. The method to control the growth directions of 1D MoO2 nanorods has potential applications in nanoelectronic devices.