Cementing failure of the casing-cement-rock interfaces during hydraulic fracturing

Hai Y. Zhu,Jin G. Deng,Jun Zhao,Hu Zhao,Hai L. Liu,Teng Wang 사단법인 한국계산역학회 2014 Computers and Concrete, An International Journal Vol.14 No.1

Using the principle of damage mechanics, zero-thickness pore pressure cohesive elements(PPCE) are used to simulate the casing-cement interface (CCI) and cement-rock interface (CRI). The traction-separation law describes the emergence and propagation of the PPCE. Mohr-coulomb criteria determines the elastic and plastic condition of cement sheath and rock. The finite element model (FEM) of delamination fractures emergence and propagation along the casing-cement-rock (CCR) interfaces during hydraulic fracturing is established, and the emergence and propagation of fractures along the wellbore axial and circumferential direction are simulated. Regadless of the perforation angle (the angle between the perforation and the max. horizontal principle stress), mirco-annulus will be produced alonge the wellbore circumferential direction when the cementation strength of the CCI and the CRI is less than the rock tensile strength; the delamination fractures are hard to propagate along the horizontal wellbore axial direction; emergence and propagation of delamination fractures are most likely produced on the shallow formationwhen the in-situ stresses are lower; the failure mode of cement sheath in the deep well is mainly interfaces seperation and body damange caused by cement expansion and contraction, or pressure testing and well shut-in operations.

Heat transfer and thermal error analysis of micro - macro coaxial driver

Hai Shun Deng,Yongtao Wang,Tian Xie,Bo Xu,Sen Huang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.10

In order to reduce the influence of temperature on the operating performance of the macro and micro drive, a double-wounding circulating water cooling structure is proposed. Based on the law of thermal resistance, the heat transfer model of the macro and micro drive forced convec-tion cooling was established, and the influencing factors of the internal temperature distribution of the macro and micro drive system were analyzed. And the macro to micro drive forced con-vection cooling when the macro dynamic system part of the output force, and the size of the output displacement and micro system of the rise of temperature of the giant magnetostrictive material (GMM) and output displacement simulation and experiment, the results show that when the circulating water flow rate is more than 3 m/s, macro to micro drive internal temperature decreased significantly, the macro dynamic range at around 1 N. The fluctuation range of macrodynamic output displacement is between 0~20 μm. The error of output displacement gen-erated by the micro-motion magnetostrictive rod is less than 1 μm, at this time, the temperature change has little influence on the output force, output displacement and micro output displace-ment of the macro-moving part.

Hydraulic fracturing experiments of highly deviated well with oriented perforation technique

Zhu, Hai Y.,Deng, Jin G.,Liu, Shu J.,Wen, Min,Peng, Cheng Y.,Li, Ji R.,Chen, Zi J.,Hu, Lian B.,Lin, Hai,Guang, Dong Techno-Press 2014 Geomechanics & engineering Vol.6 No.2

In order to investigate the effect of different perforation angles (the angle between the perforation direction and the maximum horizontal principal stress) on the fracture initiation and propagation during hydraulic fracturing of highly deviated well in oil & gas saturated formation, laboratory experiments of the hydraulic fracturing had been carried out on the basis of non-dimensional similar criteria by using 400^3 $mm^3$ cement cubes. A plane fracture can be produced when the perforations are placed in the direction of the maximum horizontal principal stress. When the perforation angle is $45^{\circ}$, the fractures firstly initiate from the perforations at the upper side of the wellbore, and then turn to the maximum horizontal principal stress direction. When the well deviation angle and perforation angle are both between $45^{\circ}$ and $90^{\circ}$, the fractures hardly initiate from the perforations at the lower side of the wellbore. Well azimuth (the angle between the wellbore axis and the maximum horizontal principal stress) has a little influence on the fracture geometries; however it mainly increases the fracture roughness, fracture continuity and the number of secondary fractures, and also increases the fracture initiation and propagation pressure. Oriented perforating technology should be applied in highly deviated well to obtain a single plane fracture. If the well deviation angle is smaller, the fractures may link up.

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.

Anisotropic Patterns of Liver Cancer Prevalence in Guangxi in Southwest China: Is Local Climate a Contributing Factor?

Deng, Wei,Long, Long,Tang, Xian-Yan,Huang, Tian-Ren,Li, Ji-Lin,Rong, Min-Hua,Li, Ke-Zhi,Liu, Hai-Zhou Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Geographic information system (GIS) technology has useful applications for epidemiology, enabling the detection of spatial patterns of disease dispersion and locating geographic areas at increased risk. In this study, we applied GIS technology to characterize the spatial pattern of mortality due to liver cancer in the autonomous region of Guangxi Zhuang in southwest China. A database with liver cancer mortality data for 1971-1973, 1990-1992, and 2004-2005, including geographic locations and climate conditions, was constructed, and the appropriate associations were investigated. It was found that the regions with the highest mortality rates were central Guangxi with Guigang City at the center, and southwest Guangxi centered in Fusui County. Regions with the lowest mortality rates were eastern Guangxi with Pingnan County at the center, and northern Guangxi centered in Sanjiang and Rongshui counties. Regarding climate conditions, in the 1990s the mortality rate of liver cancer positively correlated with average temperature and average minimum temperature, and negatively correlated with average precipitation. In 2004 through 2005, mortality due to liver cancer positively correlated with the average minimum temperature. Regions of high mortality had lower average humidity and higher average barometric pressure than did regions of low mortality. Our results provide information to benefit development of a regional liver cancer prevention program in Guangxi, and provide important information and a reference for exploring causes of liver cancer.

Pan-cancer Analysis of Tumor Mutational Burden and Homologous Recombination DNA Damage Repair Using Targeted Next-Generation Sequencing

Hai-Yun Wang,Ling Deng,Ying-Qing Li,Xiao Zhang,Ya-Kang Long,Xu Zhang,Yan-Fen Feng,Yuan He,Tao Tang,Xin-Hua Yang,Fang Wang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose Current variability in methods for tumor mutational burden (TMB) estimation and reporting demonstrates the urgent need for a homogeneous TMB assessment approach. Here, we compared TMB distributions in different cancer types using two customized targeted panels commonly used in clinical practice. Materials and Methods TMB spectra of 295- and 1021-gene panels in multiple cancer types were compared using targeted next-generation sequencing (NGS). The TMB distributions across a diverse cohort of 2,332 cancer cases were then investigated for their associations with clinical features. Treatment response data were collected for 222 patients who received immune-checkpoint inhibitors (ICIs) and their homologous recombination DNA damage repair (HR-DDR) and programmed death-ligand 1 (PD-L1) expression were additionally assessed and compared with the TMB and response rate. Results The median TMB between gene panels was similar despite a wide range in TMB values. The highest TMB was eight and 10 in patients with squamous cell carcinoma and esophageal carcinoma according to the classification of histopathology and cancer types, respectively. Twenty-three out of 103 patients (22.3%) were HR-DDR–positive and could benefit from ICI therapy; out of those 23 patients, seven patients had high TMB (p=0.004). Additionally, PD-L1 expression was not associated with TMB or treatment response among patients receiving ICIs. Conclusion Targeted NGS assays demonstrated the ability to evaluate TMB in pan-cancer samples as a tool to predict response to ICIs. In addition, TMB integrated with HR-DDR–positive status could be a significant biomarker for predicting ICI response in patients.

Tunicamycin enhances TRAIL-induced apoptosis by inhibition of cyclin D1 and the subsequent downregulation of survivin

Hai-Yan Zhang,Zhen-Xian Du,Bao-Qin Liu,Yan-Yan Gao,Xin Meng,Yifu Guan,Wei-Wei Deng,Hua-Qin Wang 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.5

TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers. TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers.

Perforation optimization of hydraulic fracturing of oil and gas well

Zhu, Hai Yan,Deng, Jin Gen,Chen, Zi Jian,An, Feng Chen,Liu, Shu Jie,Peng, Cheng Yong,Wen, Min,Dong, Guang Techno-Press 2013 Geomechanics & engineering Vol.5 No.5

Considering the influences of fluid penetration, casing, excavation processes of wellbore and perforation tunnels, the seepage-deformation finite element model of oil and gas well coupled with perforating technique is established using the tensile strength failure criterion, in which the user-defined subroutine is developed to investigate the dynamic evolvement of the reservoir porosity and permeability. The results show that the increases of perforation angle and decreases of perforation density lead to a higher fracture initiation pressure, while the changes of the perforation diameter and length have no evident influences on the fracture initiation pressure. As for initiation location for the fracture in wellbore, it is on the wellbore face while considering the presence of the casing. By contrast, the fractures firstly initiate on the root of the tunnels without considering casing. Besides, the initial fracture position is also related with the perforation angle. The fracture initiation position is located in the point far away from the wellbore face, when the perforation angle is around $30^{\circ}$; however, when the perforation angle is increased to $45^{\circ}$, a plane fracture is initiated from the wellbore face in the maximum horizontal stress direction; no fractures was found around perforation tunnels, when the angel is close to $90^{\circ}$. The results have been successfully applied in an oilfield, with the error of only 1.1% comparing the fracture initiation pressure simulated with the one from on-site experiment.

Expression of bcl-2 and p53 in Induction of Esophageal Cancer Cell Apoptosis by ECRG2 in Combination with Cisplatin

Song, Hai-Yan,Deng, Xiao-Hui,Yuan, Guo-Yan,Hou, Xin-Fang,Zhu, Zhen-Dong,Zhou, Li,Ren, Ming-Xin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Aim: To investigate the mechanisms of induction of apoptosis of esophageal cancer cells by esophageal cancer-related gene 2 (ECRG2) in combination with cisplatin (DDP). Methods: Hoechest staining was performed to analyze the effects of single ECRG2 and ECRG2 in combination with DDP on apoptosis of EC9706 cells. The expression levels of p53 and bcl-2 mRNA and protein were determined by RT-PCR and Western blotting, respectively. Results: The number of apoptotic cells after the treatment with ECRG2 in combination with DDP for 24 hours was more than that after the treatment with single ECRG2. RT-PCR and Western blotting showed that the expression levels of bcl-2 mRNA and protein were both down-regulated, while p53 mRNA and protein were both up-regulated in the cells treated with ECRG2 in combination with DDP compared with those given ECRG2 alone. Conclusion: ECRG2 in combination with DDP can enhance the apoptosis of EC9706 cells, possibly by down-regulating bcl-2 expression and up-regulating p53.

New Paradigms of Sport & physical Education in the 21st Century PROCEEDINGS 1 / 8 . Sport Biomecihaics ( Moogunghwa Rm. ) : Evaluation of Nursing technique from the viewpoint of mechanical work

(Tang Hai Peng),(Deng Xiu),(Shintaro Toyoshima) 한국체육학회 2000 The 2000 Seoul International Sport Science Congres Vol.- No.-