Rock bridge fracture model and stability analysis of surrounding rock in underground cavern group

Song Yu,Wei-shen Zhu,Wei-min Yang,Dun-fu Zhang,Qing-song Ma 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.3

Many hydropower stations in southwest China are located in regions of brittle rock mass with high geo-stresses. Under these conditions deep fractured zones often occur in the sidewalls of the underground caverns of a power station. The theory and methods of fracture and damage mechanics are therefore adopted to study the phenomena. First a flexibility matrix is developed to describe initial geometric imperfections of a jointed rock mass. This model takes into account the area and orientation of the fracturedsurfaces of multiple joint sets, as well as spacing and density of joints. Using the assumption of the equivalent strain principle, a damage constitutive model is established based on the brittle fracture criterion. In addition the theory of fracture mechanics is applied to analyze the occurrence of secondary cracks duringa cavern excavation. The failure criterion, for rock bridge coalescence and the damage evolution equation, has been derived and a new sub-program integrated into the FLAC-3D software. The model has then beenapplied to the stability analysis of an underground cavern group of a hydropower station in Sichuan province, China. The results of this method are compared with those obtained by using a conventional elasto-plastic model and splitting depth calculated by the splitting failure criterion proposed in a previous study. The results are also compared with the depth of the relaxation and fracture zone in the surrounding rock measured by field monitoring. The distribution of the splitting zone obtained both by the proposed model and by the field monitoring measurements are consistent to the validity of the theory developed herein.

Rock bridge fracture model and stability analysis of surrounding rock in underground cavern group

Yu, Song,Zhu, Wei-Shen,Yang, Wei-Min,Zhang, Dun-Fu,Ma, Qing-Song Techno-Press 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.53 No.3

Many hydropower stations in southwest China are located in regions of brittle rock mass with high geo-stresses. Under these conditions deep fractured zones often occur in the sidewalls of the underground caverns of a power station. The theory and methods of fracture and damage mechanics are therefore adopted to study the phenomena. First a flexibility matrix is developed to describe initial geometric imperfections of a jointed rock mass. This model takes into account the area and orientation of the fractured surfaces of multiple joint sets, as well as spacing and density of joints. Using the assumption of the equivalent strain principle, a damage constitutive model is established based on the brittle fracture criterion. In addition the theory of fracture mechanics is applied to analyze the occurrence of secondary cracks during a cavern excavation. The failure criterion, for rock bridge coalescence and the damage evolution equation, has been derived and a new sub-program integrated into the FLAC-3D software. The model has then been applied to the stability analysis of an underground cavern group of a hydropower station in Sichuan province, China. The results of this method are compared with those obtained by using a conventional elasto-plastic model and splitting depth calculated by the splitting failure criterion proposed in a previous study. The results are also compared with the depth of the relaxation and fracture zone in the surrounding rock measured by field monitoring. The distribution of the splitting zone obtained both by the proposed model and by the field monitoring measurements are consistent to the validity of the theory developed herein.

Esophageal Cancer Mortality during 2004-2009 in Yanting County, China

Song, Qing-Kun,Li, Jun,Jiang, Hai-Dong,He, Yu-Ming,Zhou, Xiao-Qiao,Huang, Cheng-Yu Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

Objective: Yanting County is a high risk area for esophageal cancer (EC) in China. The purpose of this study was to describe the mortality and mortality change of EC from 2004 to 2009 in Yanting County. Methods: EC mortality data from 2004 to 2009 obtained from the Cancer Registry in Yanting were analyzed. Annual percentage changes (APC) were calculated to assess the trends in EC mortality. Age-standardized mortality was calculated based on world standard population of 2000. Results: The average EC mortality was 54.7/$10^5$ in males and 31.6/$10^5$ in females over the 6 years. A decline in EC mortality with time was observed in both genders, with a rate of -8.70% per year (95% CI: -13.23%~-3.93%) in females and -4.11% per year (95%CI: -11.16%~3.50%) in males. Conclusion: EC mortality decreased over the six years in both genders, although it remained high in the Yanting area. There is still a need to carry out studies of risk factors for improved cancer prevention and further reduction in the disease burden.

Prognostic Role of C-reactive Protein in Gastric Cancer: A Meta-analysis

Yu, Qing,Yu, Xiong-Fei,Zhang, Shou-De,Wang, Hao-Hao,Wang, Hai-Yong,Teng, Li-Song Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Background: A number of studies have investigated the association between increased pretreatment serum C-reactive protein (CRP) levels and the prognosis of gastric cancer. However, due to the inconsistent results, whether the serum CRP level can be a prognostic factor in primary gastric cancer remains controversial. Methods: We searched Medline, PubMed, Embase and the Cochrane Central Register of Controlled Trials for relevant high-quality reports. A meta-analysis was carried out using the included studies to assess the association between pretreatment serum CRP level and overall survival (OS) in patients with gastric cancer. Correlation analyses were conducted to evaluate the relationship between serum CRP and tumor characteristics such as tumor node metastasis (TNM) stage and recurrence. Results: Twelve reports involving 2,597 patients with gastric cancer were included. Primary meta-analysis indicated a significant association between elevated CRP level and poor OS (HR 1.77, 95% CI 1.56-2.00). Subgroup analyses showed no single factor could alter the primary results when we divided the included studies by "number of patients", "max follow-up period", "TNM stage", "treatment" and "cut-off value". Correlation analyses showed that serum CRP level was significantly related to TNM stage (OR 2.96, 95% CI 2.22-3.93) and tumor recurrence (OR 1.81, 95% CI 1.21-2.71). Conclusions: We demonstrated that increased pretreatment serum CRP level (${\geq}10mg/L$) was significantly associated with poor prognosis in gastric cancer patients, either in early or advanced stages.

Comparison of Liver Transplantation and Liver Resection for Hepatocellular Carcinoma Patients with Portal Vein Tumor Thrombus Type I and Type II

Jia-Yu Lv,Ning-Ning Zhang,Ya-Wei Du,Ying Wu,Tian-Qiang Song,Ya-Min Zhang,Yan Qu,Yu-Xin Liu,Jie Gu,Ze-Yu Wang,Yi-Bo Qiu,Bing Yang,Da-Zhi Tian,Qing-Jun Guo,Li Zhang,Ji-San Sun,Yan Xie,Zheng-Lu Wang,Xin 연세대학교의과대학 2021 Yonsei medical journal Vol.62 No.1

Purpose: The aim of this study was to compare the efficacy of liver transplantation (LT) and liver resection (LR) for hepatocellularcarcinoma (HCC) patients with portal vein tumor thrombus (PVTT) and to investigate risk factors affecting prognosis. Materials and Methods: A total of 94 HCC patients with PVTT type I (segmental PVTT) and PVTT type II (lobar PVTT) were involvedand divided into LR (n=47) and LT groups (n=47). Recurrence-free survival (RFS) and overall survival (OS) were comparedbefore and after inverse probability of treatment weighting (IPTW). Prognostic factors for RFS and OS were explored. Results: Two treatment groups were well-balanced using IPTW. In the entire cohort, LT provided a better prognosis than LR. Among patients with PVTT type I, RFS was better with LT (p=0.039); OS was not different significantly between LT and LR(p=0.093). In subgroup analysis of PVTT type I patients with α-fetoprotein (AFP) levels >200 ng/mL, LT elicited significantly longermedian RFS (18.0 months vs. 2.1 months, p=0.022) and relatively longer median OS time (23.6 months vs. 9.8 months, p=0.065). Among patients with PVTT type II, no significant differences in RFS and OS were found between LT and LR (p=0.115 and 0.335,respectively). Multivariate analyses showed treatment allocation (LR), tumor size (>5 cm), AFP and aspartate aminotransferase(AST) levels to be risk factors of RFS and treatment allocation (LR), AFP and AST as risk factors for OS. Conclusion: LT appeared to afford a better prognosis for HCC with PVTT type I than LR, especially in patients with AFP levels>200 ng/mL.

Lysinibacillus tabacifolii sp. nov., a Novel Endophytic Bacterium Isolated from Nicotiana tabacum Leaves

Yan-Qing Duan,Song-Tao He,Qing-Qing Li,Ming-Feng Wang,Wen-Yuan Wang,Wei Zhe,Yong-Hong Cao,Ming-He Mo,Yu-Long Zhai,Wen-Jun Li 한국미생물학회 2013 The journal of microbiology Vol.51 No.3

A Gram-positive, catalase- and oxidase-positive, strictly aerobic, endospore-forming rod bacterium, designated K3514T, was isolated from the leaves of Nicotiana tabacum. The strain was able to grow at temperatures of 8–40°C, pH 5.0–10.0 and NaCl concentrations of 0–7%. The predominant quinones (>30%) of this strain were MK-7(H2) and MK-7. Phylogenetic analysis of 16S rRNA gene sequence showed that strain K3514T was affiliated to the genus Lysinibacillus, with its closest relatives being Lysinibacillus mangiferihumi (98.3% sequence similarity), Lysinibacillus sphaericus (97.9% sequence similarity), Lysinibacillus fusiformis (97.4% sequence similarity), and Lysinibacillus xylanilyticus (97.3% sequence similarity). However, low levels of DNA-DNA relatedness values suggested that the isolate was distinct from the other closest Lysinibacillus species. Additionally, based on analysis of morphological, physiological, and biochemical characteristics, the isolate could be differentiated from the closest known relatives. Therefore, based on polyphasic taxonomic data, the novel isolate likely represents a novel species, for which the name Lysinibacillus tabacifolii sp. nov. and the type strain K3514T (=KCTC 33042T =CCTCC AB 2012050T) are proposed.

Comparative Study between ZOOMit and Conventional Intravoxel Incoherent Motion MRI for Assessing Parotid Gland Abnormalities in Patients with Early- or Mid-Stage Sjögren’s Syndrome

Zhou Qing-Qing,Zhang Wei,Yu Yu-Sheng,Li Hong-Yan,Wei Liang,Li Xue-Song,He Zhen-Zhen,Zhang Hong 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.4

Objective: To compare the reproducibility and performance of quantitative metrics between ZOOMit and conventional intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) in the diagnosis of early- and mid-stage Sjögren’s syndrome (SS). Materials and Methods: Twenty-two patients (mean age ± standard deviation, 52.0 ± 10.8 years; male:female, 2:20) with early- or mid-stage SS and 20 healthy controls (46.9 ± 14.6 years; male:female, 7:13) were prospectively enrolled in our study. ZOOMit IVIM and conventional IVIM MRI were performed simultaneously in all individuals using a 3T scanner. Quantitative IVIM parameters - including tissue diffusivity (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) - inter- and intra-observer reproducibility in measuring these parameters, and their ability to distinguish patients with SS from healthy individuals were assessed and compared between ZOOMit IVIM and conventional IVIM methods, appropriately. MR gland nodular grade (MRG) was also examined. Results: Inter- and intra-observer reproducibility was better with ZOOMit imaging than with conventional IVIM imaging (ZOOMit vs. conventional, intraclass correlation coefficient of 0.897–0.941 vs. 0.667–0.782 for inter-observer reproducibility and 0.891–0.968 vs. 0.814–0.853 for intra-observer reproducibility). Significant differences in ZOOMit f, ZOOMit D*, conventional D*, and MRG between patients with SS and healthy individuals (all p < 0.05) were observed. ZOOMit D* outperformed conventional D* in diagnosing early- and mid-stage SS (area under receiver operating curve, 0.867 and 0.658, respectively; p = 0.002). The combination of ZOOMit D*, MRG, and ZOOMit f as a new diagnostic index for SS, increased diagnostic area under the curve to 0.961, which was higher than that of any single parameter (all p < 0.01). Conclusion: Considering its better reproducibility and performance, ZOOMit IVIM may be preferred over conventional IVIM MRI, and may subsequently improve the ability to diagnose early- and mid-stage SS.

Synthesis and Antibacterial Evaluation of (S,Z)-4-methyl-2-(4-oxo-5-((5-substituted phenylfuran-2-yl) methylene)-2-thioxothiazolidin-3-yl)Pentanoic Acids

Song, Ming-Xia,Deng, Xian-Qing,Wei, Zhi-Yu,Zheng, Chang-Ji,Wu, Yan,An, Chang-Shan,Piao, Hu-Ri Shaheed Beheshti University of Medical Sciences 2015 Iranian journal of pharmaceutical research Vol.14 No.1

<P>The microbial resistance has become a global hazard with the irrational use of antibiotics. Infection of drug-resistant bacteria seriously threatens human health. Currently, there is an urgent need for the development of novel antimicrobial agents with new mechanisms and lower levels of toxicity. In this paper, a series of (<I>S</I><I>,Z</I>)-4-methyl-2-(4-oxo-5-((5-substitutedphenylfuran-2-yl) methylene)-2-thioxothiazolidin-3-yl)pentanoic acids via a Knoevenagel condensation were synthesized and evaluated for their antibacterial activity <I>in</I><I>-</I><I>vitro</I>. The synthesized compounds were characterized by IR, <SUP>1</SUP>H NMR and MS. The antibacterial test<I> in</I><I>-</I><I>vitro</I> showed that all of the synthesized compounds had good antibacterial activity against several Gram-positive bacteria (including multidrug-resistant clinical isolates) with minimum inhibitory concentration (MIC) values in the range of 2–4 µg/mL. Especially compounds 4c, 4d, 4e and 4f were the most potent, with MIC values of 2 µg/mL against four multidrug-resistant Gram-positive bacterial strains.</P>

A new compound operation method of the numerical solutions And analytic solution of partial differential equation

Yu-Jie Ren,Yan-Juan Li,Fu-Gui Song,Hong-Qing Zhang 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

In the paper, a new compound operation method of the numerical solutions and analytic solution (if exist) is proposed to constructing explicit solutions for nonlinear partial differential equations based on computation system MATLAB. The validity and reliability of the method is tested by its application to the Toda-Lattice equations in (2+1) dimensions. More new explicit solutions are found. The compound operation method can be also applied to other nonlinear partial differential equations.

A mechanization method on the mixed operation of the numerical solutions, analytic solution, and showing their figures simultaneously for differential equation

Yu-Jie Ren,Fu-Gui Song,Yan-Juan Li,Hong-Qing Zhang 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

In the paper, a new mechanization method on the mixed operation of the numerical solutions, analytic solution (if exist), and showing their figures simultaneously for differential equation and their MATLAB programs are presented. With the aid of computer software MATLAB, Euler's method is chosen to illustrate the validity and advantages of the method. As a result, we can not only see the analytic solution, numerical solutions, and their errors but also observe how step size affects the error of the numerical solutions by a figure. The mechanization method can be also applied to other numerical method.