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Support design method for deep soft-rock tunnels in non-hydrostatic high in-situ stress field

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Journal of Central South University 2024年第7期31卷 2431-2445页

作者： zheng Ke-yue SHI Cheng-hua ZHAO Qian-jin LEI Ming-feng JIA Chao-jun PENG Zhu National Engineering Research Center of High-speed Railway Construction Technology Changsha 410075China School of Civil Engineering Central South UniversityChangsha 410075China China Railway Group Co. Ltd.Beijing 100039China

Due to the long-term plate tectonic movements in southwestern China,the in-situ stress field in deep formations is *** passing through deep soft-rock mass under non-hydrostatic high in-situ stress field,tunnels will suffer serious asymmetric *** is no available support design method for tunnels under such a situation in existing studies to clarify the support time and support *** study first analyzed the mechanical behavior of tunnels in non-hydrostatic in-situ stress field and derived the theoretical equations of the ground squeezing curve(GSC)and ground loosening curve(GLC).Then,based on the convergence confinement theory,the support design method of deep soft-rock tunnels under non-hydrostatic high in-situ stress field was established considering both squeezing and loosening *** addition,this method can provide the clear support time and support stiffness of the second layer of initial *** proposed design method was applied to the wanhe tunnel of the China-Laos railway in *** data indicated that the optimal support scheme had a good effect on controlling the tunnel deformation in non-hydrostatic high in-situ stress *** applications showed that the secondary lining could be constructed properly.

关键词： non-hydrostatic stress field high in-situ stress deep soft-rock tunnel squeezing pressure loosening pressure support design method

Comparison of prognosis and postoperative morbidities between standard pancreaticoduodenectomy and the TRIANGLE technique for resectable pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 689-699页

作者： He-Xing Hang zheng-hua Cai Yi-Fei Yang Xu Fu Yu-Dong Qiu Hao Cheng Division of Pancreatic Surgery Department of General SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina

BACKGROUND Radical surgery combined with systemic chemotherapy offers the possibility of long-term survival or even cure for patients with pancreatic ductal adenocar-cinoma(PDAC),although tumor recurrence,especially locally,still inhibits the treatment *** TRIANGLE technique was introduced as an extended dissection procedure to improve the R0 resection rate of borderline resectable or locally advanced ***,there was a lack of studies concerning postoperative complications and long-term outcomes of this procedure on patients with resectable *** Patients with resectable PDAC eligible for PD from our hospital between June 2018 and December 2021 were enrolled in this retrospective cohort *** the patients were divided into PDstandard and PDTRIANGLE groups according to the surgical *** characteristics,surgical data,and postoperative morbidities were *** of the patients were followed up,and the date and location of tumor recurrence,and death were *** Kaplan-Meier method and log-rank test were used for the survival *** There were 93 patients included in the study and 37 underwent the TRIANGLE *** of operation was longer in the PDTRIANGLE group compared with the PDstandard group[440(410-480)min vs 320(265-427)min](P=0.001).Intraoperative blood loss[700(500-1200)mL vs 500(300-800)mL](P=0.009)and blood transfusion[975(0-1250)mL vs 400(0-800)mL](P=0.009)were higher in the PDTRIANGLE *** was a higher incidence of surgical site infection(43.2%vs 12.5%)(P=0.001)and postoperative diarrhea(54.1%vs 12.5%)(P=0.001)in the PDTRIANGLE *** rates of R0 resection and local recurrence,overall survival,and disease-free survival did not differ significantly between the two *** The TRIANGLE technique is safe,with acceptable postoperative morbidities compared with standardized PD,but it does not improve prognosis for patients with resectable PDAC.

关键词： Pancreatic ductal adenocarcinoma TRIANGLE technique Pancreaticoduodenectomy Prognosis Postoperative morbidities

双面键合长波长垂直腔面发射激光器的制备与分析

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红外与激光工程 2010年第4期39卷 618-622页

作者：何国荣渠红伟郑婉华陈良惠深圳信息职业技术学院电子通信技术系广东深圳518029 中国科学院半导体研究所光电子中心．北京100083

研制了双面键合长波长垂直腔面发射激光器(VCSEL),有效克服了传统外延生长方法存在的诸多难题。通过对布拉格反射镜、有源区和光学腔的设计,结合键合技术进行工艺设计,于国内首次研制出双面键合长波长VCSEL,并分别采用光泵浦和电泵浦对... 详细信息

研制了双面键合长波长垂直腔面发射激光器(VCSEL),有效克服了传统外延生长方法存在的诸多难题。通过对布拉格反射镜、有源区和光学腔的设计,结合键合技术进行工艺设计,于国内首次研制出双面键合长波长VCSEL,并分别采用光泵浦和电泵浦对其进行了测试与分析。测试结果表明结构及工艺设计是合理的,两次键合后的界面可以承受腐蚀、剥离、氧化等后工艺,且键合界面光、电性能良好,未对激光器性质造成明显的不良影响。器件激射波长约为1 273.6 nm,脉冲条件下表现出动态单纵模特性,在仪器测试范围内,20μm尺寸的器件常温连续工作条件下的最大输出功率为0.16 mW。但P-I曲线的扭折说明器件仍旧存在着较大的热、电阻,需在后续的材料生长及键合技术中进一步优化。

关键词：垂直腔面发射激光器(VCSEL) 键合布拉格反射镜(DBR)

Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua CHENG School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation

Cardiovascular computed tomography in cardiovascular disease:An overview of its applications from diagnosis to prediction

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Journal of Geriatric Cardiology 2024年第5期21卷 550-576页

作者： Zhong-hua SUN Discipline of Medical Radiation Science Curtin Medical SchoolCurtin UniversityPerthAustralia Curtin Health Innovation Research Institute(CHIRI) Curtin UniversityPerth 6012Australia

Cardiovascular computed tomography angiography(CTA)is a widely used imaging modality in the diagnosis of cardiovascular *** in CT imaging technology have further advanced its applications from high diagnostic value to minimising radiation exposure to *** addition to the standard application of assessing vascular lumen changes,CTA-derived applications including 3D printed personalised models,3D visualisations such as virtual endoscopy,virtual reality,augmented reality and mixed reality,as well as CT-derived hemodynamic flow analysis and fractional flow reserve(FFRCT)greatly enhance the diagnostic performance of CTA in cardiovascular *** widespread application of artificial intelligence in medicine also significantly contributes to the clinical value of CTA in cardiovascular *** value of CTA has extended from the initial diagnosis to identification of vulnerable lesions,and prediction of disease extent,hence improving patient care and *** this review article,as an active researcher in cardiovascular imaging for more than 20 years,I will provide an overview of cardiovascular CTA in cardiovascular *** is expected that this review will provide readers with an update of CTA applications,from the initial lumen assessment to recent developments utilising latest novel imaging and visualisation *** will serve as a useful resource for researchers and clinicians to judiciously use the cardiovascular CT in clinical practice.

关键词： diagnosis cardiovascular prediction

A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China

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Petroleum Science 2024年第3期21卷 1459-1473页

作者： Peng Yang Zhan-Li Ren Jin-hua Fu Hong-Ping Bao Hui Xiao zheng Shi Kun wang Yuan-Yuan Zhang Wen-Hui Liu Wen-Hou Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an710069ShanxiChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Exploration and Development Research Institute of PetroChina Changqing Oilfield CompanyXi'an710018ShaanxiChina Shaanxi Key Lab of Petroleum Accumulation Geology School of Earth Science and EngineeringXi'an Shiyou UniversityXian710065ShaanxiChina Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxi214126JiangsuChina

The southern Ordos Basin has excellent petroleum exploration ***,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are *** this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution *** the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern *** paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source *** vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation *** Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation *** southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and *** event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and *** southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic *** southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the *** str

关键词： Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin

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Chinese Journal of Integrative Medicine 2024年第8期30卷 684-691页

作者： CAO Wei wanG Lu HOU Ting-hui SHI Yun-zhou zheng Qian-hua zheng Hui ZOU Zi-hao QIN Di YANG Qian CHEN Si-jue wanG Hai-yan XIAO Xian-jun LI Ying Department of Acupuncture and Moxibustion Chengdu University of Traditional Chinese MedicineChengdu610000China Acupuncture and Moxibustion School of Health Preservation and Rehabilitation Chengdu University of Traditional Chinese MedicineChengdu610000China

Objective To explore the demographic and disease-related factors associated with acupuncture response in patients with chronic tension-type headache(CTTH).Methods Using data from a randomized clinical trial(218 cases)consisting of 4 weeks of baseline assessment,8 weeks of treatment,and 24 weeks of follow-up,participants were regrouped into responders(at least a 50%reduction in monthly headache days at week 16 compared with baseline)and ***-three demographic and disease-related factors associated with acupuncture response in 183 participants were analyzed by multivariable logistic *** One hundred and nineteen(65.0%)participants were classified as *** factors were significantly independently associated with acupuncture response,including treatment assignment,headache intensity at baseline,and 2 domains[general health(GH)and social functioning(SF)]from the 36-Item Short Form Health Survey quality of life *** assignment was associated with non-response:participants receiving true acupuncture were 3-time more likely to achieve a CTTH response than those receiving superficial acupuncture[odds ratio(OR)0.322,95%confidence interval(CI)0.162 to 0.625,P=0.001].Compared with patients with mild-intensity headache,patients with moderate-intensity headache were twice as likely to respond to acupuncture(OR 2.001,95%CI 1.020 to 4.011,P=0.046).The likelihood of non-response increased by 4.5%with each unit increase in the GH grade(OR 0.955,95%CI 0.917 to 0.993,P=0.024)while decreased by 3.8%with each unit increase in the SF grade(OR 1.038,95%CI 1.009 to 1.069,P=0.011).Conclusions Greater headache intensity,lower GH score,and higher SF score were associated with better acupuncture responses in CTTH *** 3 factors require independent validation as predictors of acupuncture effectiveness in CTTH.

关键词： acupuncture chronic tension-type headache logistic regression quality of life Chinese medicine

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-Jing Han Ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia zheng-Ning Li hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods

Differentiation and immunosuppressive function of CD19^(+)CD24^(hi)CD27^(+) regulatory B cells are regulated through the miR-29a-3p/NFAT5 pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 472-480页

作者： Jin-Yang Li Tian-Shuo Feng Ji Gao Xin-Xiang Yang Xiang-Cheng Li Zhen-hua Deng Yong-Xiang Xia zheng-Shan Wu Hepatobiliary Center the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Liver Transplantation Chinese Academy of Medical SciencesNanjing 210029China NHC Key Laboratory of Living Donor Liver Transplantation Nanjing Medical UniversityNanjing 210029China

Background: Regulatory B cells(Bregs) is an indispensable element in inducing immune tolerance after liver transplantation. As one of the microRNAs(miRNAs), mi R-29a-3p also inhibits translation by degrading the target mRNA, and yet the relationship between Bregs and mi R-29a-3p has not yet been fully explored. This study aimed to investigate the impact of miR-29a-3p on the regulation of differentiation and immunosuppressive functions of memory Bregs(m Bregs) and ultimately provide potentially effective therapies in inducing immune tolerance after liver transplantation. Methods: Flow cytometry was employed to determine the levels of Bregs in peripheral blood mononuclear cells. TaqMan low-density array miRNA assays were used to identify the expression of different miRNAs, electroporation transfection was used to induce mi R-29a-3p overexpression and knockdown, and dual luciferase reporter assay was used to verify the target gene of miR-29a-3p. Results: In patients experiencing acute rejection after liver transplantation, the proportions and immunosuppressive function of m Bregs in the circulating blood were significantly impaired. mi R-29a-3p was found to be a regulator of m Bregs differentiation. Inhibition of miR-29a-3p, which targeted nuclear factor of activated T cells 5(NFAT5), resulted in a conspicuous boost in the differentiation and immunosuppressive function of m Bregs. The inhibition of mi R-29a-3p in CD19~+ B cells was capable of raising the expression levels of NFAT5, thereby promoting B cells to differentiate into m Bregs. In addition, the observed enhancement of differentiation and immunosuppressive function of m Bregs upon mi R-29a-3p inhibition was abolished by the knockdown of NFAT5 in B cells. Conclusions: mi R-29a-3p was found to be a crucial regulator for m Bregs differentiation and immunosuppressive function. Silencing mi R-29a-3p could be a potentially effective therapeutic strategy for inducing immune tolerance after liver transplantation.

关键词： Regulatory B cells miR-29a-3p NFAT5 Liver transplantation