Experimental and numerical investigation on post-earthquake fire behaviour of the circular concrete-filled steel tube columns

Yu-Hang Wang,Qi Tang,Mei-Ni Su,Ji-Ke Tan,Wei-Yong Wang,Yong-Sen Lan,Xiao-Wei Deng,Yong-Tao Bai,Wei Luo,Xiao-Hua Li,Jiu-Lin Bai 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.38 No.1

Post-earthquake fire is a common disaster which causes serious safety issues to infrastructures. This study aims to investigate the residual loading capacities of circular concrete-filled steel tube (CFST) columns under post-earthquake fire experimentally and numerically. The experimental programme contains two loading steps - pre-damage cyclic loading at room temperature and transient state tests with constant compression loads. Three finite element models are developed and validated against the test results. Upon validation, a total of 48 numerical results were generated in the parametric study to investigate the effects of thickness and strengths of steel tube, axial compression ratio and damage degree on the fire resistance of circular CFST columns. Based on the analysis on experimental and numerical results, the loading mechanism of circular CFST columns is discussed. A design method is proposed for the prediction of fire resistance time under different seismic pre-damage and compression loads. The predictions by the new method is compared with the newly generated experimental and numerical results and is found to be accurate and consistent with the mean value close to the unity and a coefficient of variation around 1%.

Mortality of Major Cancers in Guangxi, China: Sex, Age and Geographical Differences from 1971 and 2005

Deng, Wei,Long, Long,Li, Ji-Lin,Zheng, Dan,Yu, Jia-Hua,Zhang, Chun-Yan,Li, Ke-Zhi,Liu, Hai-Zhou,Huang, Tian-Ren Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.4

The incidence and mortality rates of liver and nasopharyngeal cancer in Guangxi province of China have always been among the highest in the world, and cancer is one of the major diseases that pose a threat to the health of residents in Guangxi. However, no systematic study has been performed to evaluate the time trends in the structure of cancer-related deaths and cancer mortality. In this study, we reveal sex, age and geography differences of cancers mortality between three death surveys (1971 to 1973, 1990 to 1992, and 2004 to 2005). The results show that the standardized mortality rate of cancer in Guangxi residents has risen from 43.3/100,000 to 84.2/100,000, the share of cancer deaths in all-cause deaths has increased from 13.3% to 20.7%, and cancer has become the second most common cause of death. The five major cancers, liver cancer, lung cancer, gastric cancer, nasopharyngeal cancer and colorectal cancer, account for 60% of all the cancer deaths. Cancers with growing mortality rates over the past 30 years include lung cancer, colorectal cancer, liver cancer and female breast cancer, of which lung cancer is associated with the sharpest rise in mortality, with a more than 600% rise in both men and women. Cancer death in Guangxi residents occurs mainly in the elderly population above 45 years of age, especially in people over the age of 65. The areas with the highest mortality rates for liver cancer and nasopharyngeal cancer, which feature regional high incidences, include Chongzuo and Wuzhou. Therefore, for major cancers such as liver cancer, lung cancer, gastric cancer, nasopharyngeal cancer and female breast cancer in Guangxi, we can select high-risk age groups as the target population for cancer prevention and control efforts in high-prevalence areas in a bid to achieve the ultimate goal of lowering cancer mortality in Guangxi.

Experimental Investigation on Energy Mechanism of Freezing-Thawing Treated Sandstone under Uniaxial Static Compression

Hongwei Deng,Songtao Yu,Junren Deng,Bo Ke,Feng Bin 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.5

To gain a further understanding of Freeze-Thaw weathering effect on the damage of sandstone from the perspective of energy analysis, uniaxial static compression tests were conducted on sandstone samples that suffered 0, 20, 60, 100 and 140 freezingthawing cycles. Then total input strain energy, releasable elastic strain energy, dissipated energy and freezing-thawing induced damage of samples under uniaxial static compression tests were calculated and analyzed. In the mean time, the energy absorption of sandstone under dynamic loading tests (SHPB (Split-Hopkinson pressure bar) experiments) were cited and made a contrast with the dissipated energy of samples under uniaxial static compression tests. The results show that the tangent modulus, total input strain energy, releasable elastic strain energy and dissipated energy of samples decrease with Freezing-Thawing cycles go on, while the freezing-thawing induced damage grow with freezing-thawing cycles increase. In term of energy used for destroying rock samples in different test modes, less energy is needed for destroying samples in uniaxial static compression tests and it decreases with F-T cycles increase, while more energy is needed for destroying samples in dynamic impact loading and it increases with F-T cycles increase. In addition, the number of fragments of broken sample increase with the F-T cycles both in uniaxial static compression tests and dynamic loading tests, and sample under dynamic loading tests is more broken than sample under uniaxial static compression tests.

Inflammatory Endotypes and Tissue Remodeling Features in Antrochoanal Polyps

Chen Cai-Ling,Wang Yu-Ting,Yao Yin,Pan Li,Guo Bei,Zhu Ke-Zhang,Ma Jin,Wang Nan,Li Xue-Li,Deng Yi-Ke,Liu Zheng 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.6

Purpose: The pathogenic mechanisms of antrochoanal polyps (ACPs) remain largely unknown. This study aimed to characterize inflammatory patterns and tissue remodeling features in ACPs. Methods: Inflammatory cell infiltration and tissue edema severity as well as fibrin deposition in ACPs and bilateral eosinophilic and noneosinophilic nasal polyps (NPs) were studied with immunohistochemical and immunofluorescence staining. Cytokine levels in sinonasal tissues were detected with the Bio-Plex assay. The expression of coagulation and fibrinolytic markers was measured using reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assays. Results: Compared to control tissues and bilateral eosinophilic and noneosinophilic NPs, ACPs had higher levels of neutrophil infiltration and expression of myeloperoxidase (MPO), interleukin (IL)-8 and interferon (IFN)-γ. In total, 94.4% of ACPs demonstrated an eosinophil cationic protein/MPO ratio of < 1, compared to 79.0% of noneosinophilic and 26% of eosinophilic NPs. Principle component and multiple correspondence analyses revealed a neutrophilic and type 1 inflammation pattern in ACPs. Compared to control tissues, edema scores and fibrin deposition were increased, whereas d-dimer and tissue plasminogen activator (tPA) levels were decreased in ACPs and bilateral NPs, with more prominent changes in ACPs even than in eosinophilic NPs. The tPA levels were negatively correlated with IFN-γ, IL-8, and MPO levels in ACPs. Neutrophils were the major cellular source of IFN-γ in ACPs, and the number of IFN-γ+ neutrophils was elevated in ACPs than in control tissues and bilateral eosinophilic and noneosinophilic NPs. Conclusions: ACPs are characterized by the neutrophilic and type 1 inflammation endotype. Neutrophil-derived IFN-γ is associated with reduced tPA production in ACPs.

Finite Element Analysis and Test Study on Restraint of High-energy Pipe Whip in Conventional Island

Ling-yun Peng,Yu-ke Deng,Hua-ting Chen,Ying-jie Kang,Xiang-xiu Li 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.4

The effects of high-energy pipe whipping after rupturing are very important in an AP1000 nuclear power plant's conventional island and restraints of pipe whipping should be considered in the design. It is the first time in the country when reinforced concrete shear walls are used as restraint services. In this paper, the behaviors of walls and restraint services subjected to pipe whipping are analyzed through static and dynamic methods in the finite element software (ABAQUS), in which all kinds of nonlinearities are considered. In addition, a test study on the restraint of pipe whipping is conducted. The results show that the wall and the restraint service can prevent pipe whipping effectively under the design load, and anchor plates arranged around the wall opening can improve the local concrete compression performance of concrete to reduce the damage of concrete. Meanwhile, the study also provides the valuable reference for wall designing to prevent from pipe whipping.

Gastrin stimulates pancreatic cancer cell directional migration by activating the Gα12/13–RhoA–ROCK signaling pathway

Ganggang Mu,Qianshan Ding,Hongyan Li,Li Zhang,Lingli Zhang,Ke He,Lu Wu,Yunchao Deng,Dongmei Yang,Lianlian Wu,Ming Xu,Jie Zhou,Honggang Yu 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

The mechanism by which gastrin promotes pancreatic cancer cell metastasis is unclear. The process of directing polarized cancer cells toward the extracellular matrix is principally required for invasion and distant metastasis; however, whether gastrin can induce this process and its underlying mechanism remain to be elucidated. In this study, we found that gastrin-induced phosphorylation of paxillin at tyrosine 31/118 and RhoA activation as well as promoted the metastasis of PANC-1 cancer cells. Depletion of Gα12 and Gα13 inhibited the phosphorylation of paxillin and downstream activation of GTP-RhoA, blocked the formation and aggregation of focal adhesions and facilitated polarization of actin filaments induced by gastrin. Suppression of RhoA and ROCK also exhibited identical results. Selective inhibition of the CCKBR–Gα12/13–RhoA–ROCK signaling pathway blocked the reoriented localization of the Golgi apparatus at the leading edge of migrated cancer cells. YM022 and Y-27632 significantly suppressed hepatic metastasis of orthotic pancreatic tumors induced by gastrin in vivo. Collectively, we demonstrate that gastrin promotes Golgi reorientation and directional polarization of pancreatic cancer cells by activation of paxillin via the CCKBR–Gα12/13–RhoA–ROCK signal pathway.