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土壤潜势氡浓度快速测量方法理论模型的建立与验证

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原子能科学技术 2013年第5期47卷 860-865页

作者：彭俊哲赵桂芝肖德涛傅燕陈泽广符适孙浩南华大学核科学技术学院湖南衡阳421001 深圳市建筑科学研究院有限公司广东深圳518049

与室内氡水平直接相关的是土壤潜势氡浓度(土壤中潜在的最大氡浓度),其直接测量深度通常需数米,测量非常困难,需探索快速获得土壤潜势氡浓度的方法。本工作通过对土壤氡运移规律的深入研究,建立了一个由土壤浅层氡浓度和土壤表面氡析出... 详细信息

与室内氡水平直接相关的是土壤潜势氡浓度(土壤中潜在的最大氡浓度),其直接测量深度通常需数米,测量非常困难,需探索快速获得土壤潜势氡浓度的方法。本工作通过对土壤氡运移规律的深入研究,建立了一个由土壤浅层氡浓度和土壤表面氡析出率确定土壤潜势氡浓度(双源法)的理论模型,并加以实验验证。实验证明了该理论模型的可靠性。该理论模型的建立为土壤潜势氡浓度快速测量方法的进一步研究奠定了基础。

关键词：土壤潜势氡浓度土壤浅层氡浓度土壤表面氡析出率双源法

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新创企业联盟网络的形成机理:一项实证研究

管理科学 2013年第6期26卷 35-47页

作者：彭伟符正平常州大学经济管理学院江苏常州213164 中山大学管理学院广州510275

整合战略行动理论和动态能力理论,以中国转型经济情境下新创企业的联盟实践为研究背景,探讨新创企业创业导向是否以及如何通过影响联盟能力而对其联盟网络嵌入性特征产生影响,揭示新创企业联盟网络的形成机理。利用151家来自广东省惠州... 详细信息

整合战略行动理论和动态能力理论,以中国转型经济情境下新创企业的联盟实践为研究背景,探讨新创企业创业导向是否以及如何通过影响联盟能力而对其联盟网络嵌入性特征产生影响,揭示新创企业联盟网络的形成机理。利用151家来自广东省惠州市仲恺国家级高新技术开发区内新创企业的问卷调查数据,综合运用线性回归分析和结构方程建模等方法对研究假设进行实证检验。研究结果表明,新创企业创业导向对其联盟网络关系强度和中心性位置都具有显著的正向影响,新创企业创业导向对其联盟能力具有显著的促进作用,联盟能力在新创企业创业导向与其联盟网络嵌入性特征关系中发挥中介作用。研究结果对中国新创企业构建联盟网络具有重要的启示意义。

关键词：新创企业创业导向联盟能力联盟网络

常规和倒置A^2/O工艺活性污泥微生物群落结构的比较

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中国环境科学 2017年第3期37卷 1137-1145页

作者：李鹏毕学军王军汝少国山东省环境保护科学研究设计院山东济南250013 中国海洋大学海洋生命学院山东青岛266003 青岛理工大学环境与市政工程学院山东青岛266033

为了探究倒置A^2/O工艺脱氮除磷效果优于常规A^2/O工艺的机理,利用聚合酶链式反应-变形梯度凝胶电泳(PCR-DGGE)技术与纯培养方法分析了2种工艺活性污泥中微生物群落结构.结果显示,2种工艺活性污泥的优势菌群均含有β-变形菌与γ-变形菌... 详细信息

为了探究倒置A^2/O工艺脱氮除磷效果优于常规A^2/O工艺的机理,利用聚合酶链式反应-变形梯度凝胶电泳(PCR-DGGE)技术与纯培养方法分析了2种工艺活性污泥中微生物群落结构.结果显示,2种工艺活性污泥的优势菌群均含有β-变形菌与γ-变形菌;倒置A^2/O工艺活性污泥中检测到大量的亚硝化螺旋菌、红环菌和4种未培养的拟杆菌,而这些菌类在常规A^2/O工艺中含量较少;利用纯培养方法在倒置A^2/O工艺活性污泥检测到的γ-变形菌纲希瓦氏菌属、克雷伯氏菌属和类球红细菌在常规A^2/O工艺样品中未检测到.推测以上菌种的存在可能是倒置A^2/O工艺具有较高脱氮除磷效果的主要原因.此外,扫描电镜结果显示倒置A^2/O工艺活性污泥较为疏松,丝状细菌含量较少,且不存在念珠状细菌.

关键词：活性污泥微生物群落结构 PCR-DGGE 倒置A2/O

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楔环连接结构参数化有限元优化设计

机械强度 2005年第2期27卷 191-195页

作者：黄鹏莫军徐兵中国工程物理研究院

利用APDL语言对ANSYS软件进行二次开发,建立楔环连接结构的参数化有限元模型。为提高该连接结构的强度,文中以楔环尺寸及环腔倒角为设计变量,以结构最大应力比为目标函数,建立优化数学模型,采用梯度法进行求解,优化后的结果表明,拉伸载... 详细信息

利用APDL语言对ANSYS软件进行二次开发,建立楔环连接结构的参数化有限元模型。为提高该连接结构的强度,文中以楔环尺寸及环腔倒角为设计变量,以结构最大应力比为目标函数,建立优化数学模型,采用梯度法进行求解,优化后的结果表明,拉伸载荷下结构的最大等效应力降低26.4%,安全系数由1.08提高到1.46,且结构的刚度得以增强。文中的实践说明,采用非线性有限元法和优化方法对连接结构进行优化能够取得满意的效果。

关键词：楔环连接结构有限元模型优化设计

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香港与大陆上市公司非公允关联交易比较

同济大学学报（自然科学版） 2009年第6期37卷 843-846页

作者：彭俊于雯雯同济大学经济与管理学院上海200092

通过构建六大非公允关联交易的预警指标并结合统计检验分析方法,以2006年度A股和H-A股各41家单位相关数据,对大陆和香港如何规制关联交易进行比较,发现H-A股发生非关联交易的可能性小于A股,主要原因在于香港的法律环境比较优越,上市规... 详细信息

通过构建六大非公允关联交易的预警指标并结合统计检验分析方法,以2006年度A股和H-A股各41家单位相关数据,对大陆和香港如何规制关联交易进行比较,发现H-A股发生非关联交易的可能性小于A股,主要原因在于香港的法律环境比较优越,上市规则比较严格和规范.对关联交易的各项规制比大陆严格,尤其是对关联交易信息披露的要求大大制约了非公允关联交易的发生率.所以,规范上市规则、严格关联交易信息披露是抑制非公允关联交易的有效途径.

关键词：上市公司非公允关联交易法律规制

Daclatasvir plus asunaprevir in treatment-na?ve patients with hepatitis C virus genotype 1b infection

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World Journal of Gastroenterology 2018年第12期24卷 1361-1372页

作者： Lai Wei fu-Sheng Wang Ming-Xiang Zhang Ji-Dong Jia Alexey A Yakovlev Wen Xie Eduard Burnevich jun-Qi Niu Yong Jin jung Xiang-jun Jiang Min Xu Xin-Yue Chen Qing Xie jun Li Jin-Lin Hou Hong Tang Xiao-guang Dou Yash Gandhi Wen-Hua Hu Fiona McPhee Stephanie Noviello Michelle Treitel Ling Mo jun Deng Peking University People’s Hospital and Peking University Hepatology Institute Beijing 100044China Qingdao Municipal Hospital Qingdao 266011Shandong ProvinceChina Guangzhou No.8 People’s Hospital Guangzhou 510060Guangdong ProvinceChina Beijing Youan Hospital Capital Medical UniversityBeijing 100069China Shanghai Ruijin Hospital Jiaotong University School of MedicineShenyang 200025Liaoning ProvinceChina TheFirst Affiliated Hospital with Nanjing Medical University Nanjing 210029Jiangsu ProvinceChina Hepatology Unit Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina West China Hospital Sichuan UniversityChengdu 610041Sichuan ProvinceChina China Medical University Shengjing HospitalShenyang 110004Liaoning ProvinceChina Bristol-Myers Squibb PrincetonNJ 08540United States Bristol-Myers Squibb WallingfordCT 06492United States 302 Military Hospital of China Beijing 100039China Bristol-Myers Squibb Shanghai 200040China the Sixth People’s Hospital of Shenyang Shenyang 110006Liaoning ProvinceChina Beijing Friendship Hospital Capital Medical UniversityBeijing 100050China Saint-Petersburg State Healthcare Institution'Clinical Infectious Hospital n.a.S.P.Botkin’ Saint-Petersburg 191167Russia Beijing Ditan Hospital Capital Medical UniversityBeijing 100015China I.M.Sechenov First Moscow State Medical University Moscow 119991Russia The First Hospital of Jilin University Jilin 1300021Jilin ProvinceChina SMG-SNU Boramae Medical Center Seoul 07061South Korea

AIM To assess daclatasvir plus asunaprevir(d UAL) in treatment-na?ve patients from China's Mainland, Russia and South Korea with hepatitis C virus(HCV) genotype 1 b infection. METHODS Patients were randomly assigned(3:1) to receive 24 wk of treatment with d UAL(daclatasvir 60 mg once daily and asunaprevir 100 mg twice daily) beginning on day 1 of the treatment period(immediate treatment arm) or following 12 wk of matching placebo(placebodeferred treatment arm). The primary endpoint was a comparison of sustained virologic response at posttreatment week 12(SVR12) compared with the historical SVR rate for peg-interferon plus ribavirin(70%) among patients in the immediate treatment arm. The first 12 wk of the study were blinded. Safety was assessed in d UAL-treated patients compared with placebo patients during the first 12 wk(doubleblind phase), and during 24 wk of d UAL in both arms *** In total, 207 patients were randomly assigned to immediate(n = 155) or placebo-deferred(n = 52) treatment. Most patients were Asian(86%), female(59%) and aged < 65 years(90%). Among them, 13% had cirrhosis, 32% had IL28 B non-CC genotypes and 53% had baseline HCV RNA levels of ≥ 6 million IU/m L. Among patients in the immediate treatment arm, SVR12 was achieved by 92%(95% confidence interval: 87.2-96.0), which was significantly higher than the historical comparator rate(70%). SVR12 was largely unaffected by cirrhosis(89%), age ≥ 65 years(92%), male sex(90%), baseline HCV RNA ≥ 6 million(89%) or IL28 B non-CC genotypes(96%), although SVR12 was higher among patients without(96%) than among those with(53%) baseline NS5 A resistanceassociated polymorphisms(at L31 or Y93 H). during the double-blind phase, aminotransferase elevations were more common among placebo recipients than among patients receiving d UAL. during 24 wk of d UAL therapy(combined arms), the most common adverse events(≥ 10%) were elevated alanine aminotransferase and upper respiratory tract infection; emergent

关键词： Asunaprevir Daclatasvir Direct-acting antiviral Chronic hepatitis C Liver disease NS3 NS5A Genotype 1b

Initial Pre-stress Finding and Structural Behaviors Analysis of Cable Net Based on Linear Adjustment Theory

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Journal of Shanghai Jiaotong university(Science) 2008年第2期13卷 155-160页

作者：任涛陈务军付功义 Space Structure Research Center Shanghai Jiaotong University

The tensile cable-strut structure is a self-equilibrate pre-stressed *** initial pre-stress cal- culation is the fundamental structural analysis.A new numerical procedure was *** force density method is the cornerstone of analytical formula,and then introduced into linear adjustment theory;the least square least norm solution,the optimized initial pre-stress,is *** initial pre-stress and structural performances of a particular single-layer saddle-shaped cable-net structure were analyzed with the developed method,which is proved to be efficient and *** modal analyses were performed with respect to various pre-stress ***,the structural performances were investigated comprehensively.

关键词： linear adjustment theory tensile cable-net structure initial pre-stress single-layer saddle-shaped cable net structural performances analysis

Association of Estrogen Receptor Gene Polymorphisms and Primary Biliary Cirrhosis in a Chinese Population： A Case- Control Study

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Chinese Medical Journal 2015年第22期128卷 3008-3014页

作者： Liu Yang Hong Zhang Yan-Fang Jiang Qing-Long Jin peng Zhang Xu Li Pu-jun Gao jun-Qi Niu Department of Hepatology First Hospital Jilin University Changchun Jilin 130021 China National Clinical Research Center of Kidney Diseases Jinling Hospital Nanjing university School of Medicinel Nanjing Jiangsu 210002 China Phase I Clinical Trials Unit First Hospital Jilin University Changchun Jilin 130021 China

Background： Primary biliary cirrhosis （PBC） is a chronic and slowly progressive cholestatic liver disease characterized by destruction of the interlobular bile ducts and a striking female predominance, The aim of this study was to identity associations between estrogen receptor （ESR） gene polymorphisms with the risk of developing PBC and abnormal serum liver tests in a Chinese population. Methods： Thirty-six patients with PBC （case group） and 35 healthy individuals （control group） from the First Hospital of Jilin University were studied. Whole genomic DNA was extracted from all the participants. Three single-nucleotide polymorphisms （rs2234693~ rs2228480, and rs3798577） from ESR1 and two （rs1256030 and rs1048315） from ESR2 were analyzed by a pyrosequencing method. Demographic data and liver biochemical data were collected. Results： Subjects with the T allele at ESR2 rs1256030 had 1.5 times higher risk of developing PBC than those with the C allele （odds ratio [OR] = 2.1277, 95% confidence interval [CI] = 1.1872-4.5517）. Haplotypes TGC of ESRI rs2234693, rs2228480, and rs3798577 were risk thctors for having PBC. The C allele at ESRI rs2234693 was associated with abnormal alkaline phosphatase （OR 5.2469, 95% CI = 1.3704-20.0895） and gamma-glutamyl transferase （OR = 3.4286, 95% CI = 1.0083-13.6578） levels in PBC patients. Conclusions： ESR2 rs1256030 T allele may be a significant risk factor for the development of PBC. Screening for patients with gene polymorphisms may help to make early diagnoses in patients with PBC.

关键词： Estrogen Receptor Gene Polymorphism Primary Biliary Cirrhosis

AaWRKY17, a positive regulator of artemisinin biosynthesis, is involved in resistance to Pseudomonas syringae in Artemisia annua

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Horticulture Research 2021年第1期8卷 2926-2936页

作者： Tiantian Chen Yongpeng Li Lihui Xie Xiaolong Hao Hang Liu Wei Qin Chen Wang Xin Yan Kuanyu Wu-Zhang Xinghao Yao Bowen peng Yaojie Zhang Xueqing fu Ling Li Kexuan Tang Joint International Research Laboratory of Metabolic and Developmental Sciences Frontiers Science Center for Transformative MoleculesPlant Biotechnology Research CenterFudan-SJTU-Nottingham Plant Biotechnology R&D CenterSchool of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China Laboratory of Medicinal Plant Biotechnology College of PharmacyZhejiang Chinese Medical UniversityHangzhou 310053China

Artemisia annua,a traditional Chinese medicinal plant,remains the only plant source for artemisinin production,yet few genes have been identified to be involved in both the response to biotic stresses,such as pathogens,and artemisinin ***,we isolated and identified the WRKY transcription factor(TF)AaWRKY17,which could significantly increase the artemisinin content and resistance to Pseudomonas syringae in *** one-hybrid(Y1H),dual-luciferase(dual-LUC),and electrophoretic mobility shift assay(EMSA)results showed that AaWRKY17 directly bound to the W-box motifs in the promoter region of the artemisinin biosynthetic pathway gene amorpha-4,11-diene synthase(ADS)and promoted its ***-time quantitative PCR(RT-qPCR)analysis revealed that the transcript levels of two defense marker genes,Pathogenesis-Related 5(PR5)and NDR1/HIN1-LIKE 10(NHL10),were greatly increased in AaWRKY17-overexpressing transgenic *** ***,overexpression of AaWRKY17 in *** resulted in decreased susceptibility to *** results indicated that AaWRKY17 acted as a positive regulator in response to *** ***,our findings demonstrated that the novel WRKY transcription factor AaWRKY17 could potentially be used in transgenic breeding to improve the content of artemisinin and pathogen tolerance in ***.

关键词： expression AaW resistance