Failure analysis of prestressed concrete containment vessels under internal pressure considering thermomechanical coupling

Wu Yu-Xiao,Fei Zi-Jian,Feng De-Cheng,Song Meng-Yan 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12

After a loss of coolant accident (LOCA) in the prestressed concrete containment vessels (PCCVs) of nuclear power plants, the coupling of temperature and pressure can significantly affect the mechanical properties of the PCCVs. However, there is no consensus on how this coupling affects the failure mechanism of PCCVs. In this paper, a simplified finite element modeling method is proposed to study the effect of temperature and pressure coupling on PCCVs. The experiment results of a 1:4 scale PCCV model tested at Sandia National Laboratory (SNL) are compared with the results obtained from the proposed modeling approach. Seven working conditions are set up by varying the internal and external temperatures to investigate the failure mechanism of the PCCV model under the coupling effect of temperature and pressure. The results of this paper demonstrate that the finite element model established by the simplified finite element method proposed in this paper is highly consistent with the experimental results. Furthermore, the stress-displacement curve of the PCCV during loading can be divided into four stages, each of which corresponds to the damage to the concrete, steel liner, steel rebar, and prestressing tendon. Finally, the failure mechanism of the PCCV is significantly affected by temperature.

Association between Cigarette Smoking and RASSF1A Gene Promoter Hypermethylation in Lung Cancer Patients: a Meta-analysis

Wu, Xiao-Ming,Chen, Yu,Shao, Yang,Zhou, Xiao-Long,Tang, Wen-Ru Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Objectives: Epidemiological studies have shown that molecular mechanisms underlying the development of lung cancers differ between smokers and unsmokers. Aberrant promoter methylation in some tumor suppressor genes is frequent in lung tumors from smokers but rare in those from non-smokers. Recently, many studies have investigated the association between cigarette smoking and RASSF1A gene promoter hypermethylation in lung cancer patients, but a unanimous conclusion could not be reached. We therefore performed this meta-analysis to derive a more precise estimation of any association. Study Design: An electronic search of PubMed and Chinese Biomedicine databases was conducted to select studies. A total of 19 case-control studies were chosen, and odds ratios (ORs) with confidence intervals (CIs) were used to assess the strength of associations. Results: The case-control studies covered 2, 287 lung cancer patients: 63.4%(1449) of the patients were smokers, 36.6% (838) were unsmokers. The overall results suggested that smokers with lung cancer had a 1.297-fold (95% CI: 1.066~1.580, p=0.010, p=0.087) higher risk for RASSF1A gene hypermethylation than the non-smokers. In the stratified analysis, an increased risk of RASSF1A gene hypermethylation in smokers than in non-smokers was found in Asian (OR=1.481, 95%CI: 1.179~1.861, p=0.001, p=0.186). Conclusions: This meta-analysis supports the idea that RASSF1A gene hypermethylation is associated with cigarette smoking-induced lung cancer.

RASSF1A Gene Methylation is Associated with Nasopharyngeal Carcinoma Risk in Chinese

Wu, Kun,Xu, Xiao-Ning,Chen, Yu,Pu, Xiao-Lin,Wang, Bo-Yuan,Tang, Xiao-Dan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

In order to explore the association between RASSF1A methylation and nasopharyngeal carcinoma (NPC) risk of Chinese, we carried out a meta-analysis with searches of PubMed, Web of Science, ProQest and Medline databases. Ultimately, 14 articles were identified and analysised using R Software (R version 3.1.2) including meta packages. Overall, we found a significant relationship between RASSF1A methylation and NPC risk (OR 30.7; 95 % CI, 16.71~56.23; z=11.0591; p<0.0001) in a fixed effects model and (OR 32.1; 95% CI, 14.27~72.01; z=8.3984; p<0.0001) in a random effects model pooled. In tissue and NP brushings groups, similar results were found. Hence, our study identified a strong association between RASSF1A methylation and NPC and highlighted a promising potential for RASSF1A methylation in NPC risk prediction of Chinese.

Cloning and Characterization of a Novel Mannanase from Paenibacillus sp. BME-14

( Xiao Yu Fu ),( Xiao Luo Huang ),( Peng Fu Liu ),( Ling Lin ),( Gao Bing Wu ),( Chan Juan Li ),( Chun Fang Feng ),( Yu Zhi Hong ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.3

근린 주거환경이 노인의 사회적 네트워크 형성에 미치는 영향 - 중국 동북 지역을 중심으로 -

무효우(Wu, Xiao-Yu),이경훈(Lee, Kyung-Hoon) 대한건축학회 2019 대한건축학회논문집 Vol.35 No.8

The purpose of this study was to explore the influence of the topography and the neighborhood facility on the aged people’s social network formation. The paper samples the aged people living in Changchun city located in a flat ground and Tonghua city located in a mountain region. Four selections of dwelling districts from the two cities are based on amount of the facilities maintaining the wealth and living area same to do the questionnaires. One hundred aged people are selected in the each dwelling district to fill out the questionnaires, and 386 valid questionnaires are finally obtained. The data obtained from the questionnaires are used to do some statistic analysis by using SPSS24.0 program. The results are shown as following: In the case of same amount of neighborhood facility for dwelling district, the aged people living in a flat ground use the facility more frequently and communicate more often with their friends and neighbors than the aged people living in a mountain region do, the social network forms more easily as well. In the other case of same topography dwelling districts, the aged people living in an abundant facility dwelling district use the facility more frequently and communicate more with their neighbors and friends than the aged people living in a mountain region do, so the social network forms more easily as well. Thus it can be seen that topography and amount of facility are significant influence factors of the aged social network formation.

Serum Tumor Marker Levels might have Little Significance in Evaluating Neoadjuvant Treatment Response in Locally Advanced Breast Cancer

Wang, Yu-Jie,Huang, Xiao-Yan,Mo, Miao,Li, Jian-Wei,Jia, Xiao-Qing,Shao, Zhi-Min,Shen, Zhen-Zhou,Wu, Jiong,Liu, Guang-Yu Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.11

Background: To determine the potential value of serum tumor markers in predicting pCR (pathological complete response) during neoadjuvant chemotherapy. Materials and Methods: We retrospectively monitored the pro-, mid-, and post-neoadjuvant treatment serum tumor marker concentrations in patients with locally advanced breast cancer (stage II-III) who accepted pre-surgical chemotherapy or chemotherapy in combination with targeted therapy at Fudan University Shanghai Cancer Center between September 2011 and January 2014 and investigated the association of serum tumor marker levels with therapeutic effect. Core needle biopsy samples were assessed using immunohistochemistry (IHC) prior to neoadjuvant treatment to determine hormone receptor, human epidermal growth factor receptor 2(HER2), and proliferation index Ki67 values. In our study, therapeutic response was evaluated by pCR, defined as the disappearance of all invasive cancer cells from excised tissue (including primary lesion and axillary lymph nodes) after completion of chemotherapy. Analysis of variance of repeated measures and receiver operating characteristic (ROC) curves were employed for statistical analysis of the data. Results: A total of 348 patients were recruited in our study after excluding patients with incomplete clinical information. Of these, 106 patients were observed to have acquired pCR status after treatment completion, accounting for approximately 30.5% of study individuals. In addition, 147patients were determined to be Her-2 positive, among whom the pCR rate was 45.6% (69 patients). General linear model analysis (repeated measures analysis of variance) showed that the concentration of cancer antigen (CA) 15-3 increased after neoadjuvant chemotherapy in both pCR and non-pCR groups, and that there were significant differences between the two groups (P=0.008). The areas under the ROC curves (AUCs) of pre-, mid-, and post-treatment CA15-3 concentrations demonstrated low-level predictive value (AUC=0.594, 0.644, 0.621, respectively). No significant differences in carcinoembryonic antigen (CEA) or CA12-5 serum levels were observed between the pCR and non-pCR groups (P=0.196 and 0.693, respectively). No efficient AUC of CEA or CA12-5 concentrations were observed to predict patient response toward neoadjuvant treatment (both less than 0.7), nor were differences between the two groups observed at different time points. We then analyzed the Her-2 positive subset of our cohort. Significant differences in CEA concentrations were identified between the pCR and non-pCR groups (P=0.039), but not in CA15-3 or CA12-5 levels (p=0.092 and 0.89, respectively). None of the ROC curves showed underlying prognostic value, as the AUCs of these three markers were less than 0.7. The ROC-AUCs for the CA12-5 concentrations of inter-and post-neoadjuvant chemotherapy in the estrogen receptor negative HER2 positive subgroup were 0.735 and 0.767, respectively. However, the specificity and sensitivity values were at odds with each other which meant that improving either the sensitivity or specificity would impair the efficiency of the other. Conclusions: Serum tumor markers CA15-3, CA12-5, and CEA might have little clinical significance in predicting neoadjuvant treatment response in locally advanced breast cancer.

Microstructure evolution and effect on deuterium retention in oxide dispersion strengthened tungsten during He⁺ irradiation

Ding, Xiao-Yu,Xu, Qiu,Zhu, Xiao-yong,Luo, Lai-Ma,Huang, Jian-Jun,Yu, Bin,Gao, Xiang,Li, Jian-Gang,Wu, Yu-Cheng Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.12

Oxide dispersion-strengthened materials W-1wt%Pr₂O₃ and W-1wt%La₂O₃ were synthesized by wet chemical method and spark plasma sintering. The field emission scanning electron microscopy (FE-SEM) analysis, XRD and Vickers microhardness measurements were conducted to characterize the samples. The irradiations were carried out with a 5 keV helium ion beam to fluences up to 5.0 × 10²¹ ions/m² under 600 ℃ using the low-energy ion irradiation system. Transmission electron microscopy (TEM) study was performed to investigate the microstructural evolution in W-1wt%Pr₂O₃ and W-1wt%La₂O₃. At 1.0 × 10²⁰ He⁺/m², the average loops size of the W-1wt%Pr₂O₃ was 4.3 nm, much lower than W-1wt% La₂O₃ of 8.5 nm. However, helium bubbles were not observed throughout in both doped W materials. The effects of pre-irradiation with 1.0 × 10²¹ He⁺/m² on trapping of injected deuterium in doped W was studied by thermal desorption spectrometry (TDS) technique using quadrupole mass spectrometer. Compared with the samples without He⁺ pre-irradiation, deuterium (D) retention of doped W materials increased after He⁺ irradiation, whose retention was unsaturated at the damage level of 1.0 × 10²²D₂⁺/m². The present results implied that irradiation effect of He⁺ ions must be taken into account to evaluate the deuterium retention in fusion material applications.

A small hairpin RNA targeting myeloid cell leukemia-1 enhances apoptosis in host macrophages infected with Mycobacterium tuberculosis

Fei-yu Wang,Yu-qing Zhang,Xin-min Wang,Chan Wang,Xiao-fang Wang,Jiang-dong Wu,Fang Wu,Wan-jiang Zhang,Le Zhang 한국미생물학회 2016 The journal of microbiology Vol.54 No.4

Myeloid cell leukemia-1 (Mcl-1) plays an important role in various cell survival pathways. Some studies indicated that the expression of Mcl-1 was upregulated in host cells during infection with the virulent Mycobacterium tuberculosis strain, H37Rv. The present study was designed to investigate the effect of inhibiting Mcl-1 expression both in vivo and in vitro on apoptosis of host macrophages infected with M. tuberculosis using a small hairpin (sh)RNA. Mcl-1 expression was detected by the real time-polymerase chain reaction, western blotting, and immunohistochemistry. Flow cytometry and transmission electron microscopy were used to measure host macrophage apoptosis. We found elevated Mcl-1 levels in host macrophages infected with M. tuberculosis H37Rv. The expression of Mcl-1 was downregulated efficiently in H37Rv-infected host macrophages using shRNA. Knockdown of Mcl-1 enhanced the extent of apoptosis in H37Rv-infected host macrophages significantly. The increased apoptosis correlated with a decrease in M. tuberculosis colony forming units recovered from H37Rv-infected cells that were treated with Mcl-1-shRNA. Reducing Mcl-1 accumulation by shRNA also reduced accumulation of the anti-apoptotic gene, Bcl-2, and increased expression of the pro-apoptotic gene, Bax, in H37Rv-infected host macrophages. Our results showed that specific knockdown of Mcl-1 expression increased apoptosis of host macrophages significantly and decreased the intracellular survival of a virulent strain of M. tuberculosis. These data indicate that interference with Mcl-1 expression may provide a new avenue for tuberculosis therapy.

Effect of Trichostatin A on CNE2 Nasopharyngeal Carcinoma Cells - Genome-wide DNA Methylation Alteration

Yang, Xiao-Li,Zhang, Cheng-Dong,Wu, Hua-Yu,Wu, Yong-Hu,Zhang, Yue-Ning,Qin, Meng-Bin,Wu, Hua,Liu, Xiao-Chun,Lina, Xing,Lu, Shao-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Trichostatin A (TSA) is a histone deacetylase (HDAC) inhibitor. We here investigated its effects on proliferation and apoptosis of the CNE2 carcinoma cell line, and attempted to establish genome-wide DNA methylation alteration due to differentially histone acetylation status. After cells were treated by TSA, the inhibitory rate of cell proliferation was examined with a CCK8 kit, and cell apoptosis was determined by flow cytometry. Compared to control, TSA inhibited CNE2 cell growth and induced apoptosis. Furthermore, TSA was found to induce genome-wide methylation alteration as assessed by genome-wide methylation array. Overall DNA methylation level of cells treated with TSA was higher than in controls. Function and pathway analysis revealed that many genes with methylation alteration were involved in key biological roles, such as apoptosis and cell proliferation. Three genes (DAP3, HSPB1 and CLDN) were independently confirmed by quantitative real-time PCR. Finally, we conclude that TSA inhibits CNE2 cell growth and induces apoptosis in vitro involving genome-wide DNA methylation alteration, so that it has promising application prospects in treatment of NPC in vivo. Although many unreported hypermethylated/hypomethylated genes should be further analyzed and validated, the pointers to new biomarkers and therapeutic strategies in the treatment of NPC should be stressed.

Salivary Pepsin as an Intrinsic Marker for Diagnosis of Sub-types of Gastroesophageal Reflux Disease and Gastroesophageal Reflux Disease-related Disorders

( Yan-jun Wang ),( Xiu-qiong Lang ),( Dan Wu ),( Yu-qin He ),( Chun-hui Lan ),( Xiao-xiao ),( Bin Wang ),( Duo-wu Zou ),( Ji-min Wu ),( Yong-bin Zhao ),( Peter W Dettmar ),( Dong-feng Chen ),( Min Yan 대한소화기 기능성질환·운동학회 2020 Journal of Neurogastroenterology and Motility (JNM Vol.26 No.1

Background/Aims To determine the value of salivary pepsin in discriminating sub-types of gastroesophageal reflux disease (GERD) and GERD-related disorders. Methods Overall, 322 patients with different sub-types of GERD and 45 healthy controls (HC) were studied. All patients took Gastroesophageal Reflux Disease Questionnaire (GerdQ) and underwent endoscopy and 24-hour esophageal pH monitoring and manometry. Salivary pepsin concentration (SPC) was detected by using colloidal gold double-antibody immunological sandwich assay. Oral esomeprazole treatment was administrated in the patients with non-erosive reflux disease (NERD) and extra-esophageal symptoms (EES). Results Compared to HC, patients with erosive esophagitis, NERD, EES, EES plus typical GERD symptoms, or Barrett’s esophagus had a higher prevalence of saliva and SPC (all P < 0.001). There was no significant difference in the positive rate for pepsin in patients with functional heartburn or GERD with anxiety and depression, compared to HC. After esomeprazole treatment, the positive rate and SPC were significantly reduced in NERD (both P < 0.001) and in EES (P = 0.001 and P = 0.002, respectively). Of the 64 NERD patients, 71.9% (n = 46) were positive for salivary pepsin, which was significantly higher than the rate (43.8%, n = 28) of pathological acid reflux as detected by 24-hour esophageal pH monitoring (P = 0.002). Conclusions Salivary pepsin has an important significance for the diagnosis of GERD and GERD-related disorders. Salivary pepsin and 24-hour esophageal pH monitoring may complement with each other to improve the diagnostic efficiency.