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The impact of farmers’ assessments of risk management strategies on their adoption willingness

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Journal of Integrative Agriculture 2021年第12期20卷 3323-3338页

作者： shang yan XIONG Tao College of Economics and Management Huazhong Agricultural UniversityWuhan 430070P.R.China

Farmers'assessments of risk management strategies and how the assessments influence their willingness to adopt these strategies are poorly understood.This study conducts a structured survey of 469 farmers to investigate how farmers assess both crop insurance and crop price insurance,the impact of the assessments on their adoption willingness,and in particular,the differences in assessments and adoption willingness between crop insurance and crop price insurance.Empirical results show that farmers’assessments on crop insurance can be significantly improved through communication and experience.The most effective way to improve farmers'assessments on crop price insurance is providing adequate information about the insurance products.Furthermore,farmers'adoption willingness would be enhanced by improved assessment of both crop yield and crop price insurance.This study provides the first empirical evidence that farmers have limited information to assess insurance,which significantly influences their willingness to adopt.This finding reflects that the dissemination of insurance policies,the effectiveness of insurance,and the availability of insurance services significantly enable farmers'ability to assess risk management strategies,which potentially increases farmers'willingness to adopt insurance.

关键词： assessments adoption willingness crop insurance crop price insurance protection motivation theory(PMT)

Expression and significance of netrin-1 and its receptor UNC5C in precocious puberty female rat hypothalamus

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Asian Pacific Journal of Tropical Medicine 2015年第3期8卷 234-238页

作者： yan-Chao shang Jie Zhang yan-Qiu shang Maternal and Children Health Hospital Affiliated Hospital of Hebei United University

Objective:To study expressions of netrin-1 and its receptor UNC5 C in female precocious puberty rat hypothalamus,and explore its effect on precocious puberty process.Methods:Forty female one-week-old SD rats were randomly divided into four groups:experimental group A(precocious puberty early youth),experimental group B(precocious puberty medium youth),group A(normal pre-puberty).group B(normal early youth) with 10 rats in each group.Precocious puberty experimental rats were induced with Danazol and rals in control group were injected with saline.Uterus and ovaries were removed,specimens were weighed,litems index and ovarian index were calculated,and amount of luteinizing hormone(LH) and follicle-stimulating hormone(FSH) were detected from the blood by ELISA.Real-time PCR was used to delect netrin-1 and its receptor UNC5 C.as well as hypothalamic gonadolropinreleasing hormone(GnRH) mRNA expression in hypothalamus tissues:and then,a coimmunoprecipitation study of interactions between netrin-1 and its receptor UNC5 C was carried out.Results:Relative target gene expression levels of control group A,control group B.experimental group A,and experimental group B(with,3-actin as an internal control for normalization) were as follows:Netrin-1:3.5±0.9,5.4±0.***.4.9±1.***.5.3±0.3:UNC5C:0.8±0.***.1.7±0.***.1.82±0.***.1.58±0.4:GnRH:1.2±0.***.2.7±0.***.2.4±0.***.3.2±0.4.Conclusions:LH and FSH concentrations,netrin-1 and its receptor expression are increased in precocious puberty animal models.

关键词： Netrin-1 UNC5C Central precocious puberty

超临界CO_(2)管道瞬态输送工艺研究进展及方向

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大庆石油地质与开发 2024年第1期43卷 22-32页

作者：李欣泽袁亮张超王梓丞邢晓凯熊小琴陈晓玲尚妍张文辉陈潜中国石油大学(北京)克拉玛依校区工学院新疆克拉玛依834000 中国石油新疆油田公司开发公司新疆克拉玛依834000 中国石油新疆油田公司基本建设工程处新疆克拉玛依834000 中国石油新疆油田公司工程技术研究院新疆克拉玛依834000 长江大学石油工程学院湖北武汉430100

长距离超临界CO_(2)管道瞬态输送的核心技术还有待突破,相关模型和方法亟需工业规模示范工程的验证及修正。以成就型综述法,对超临界CO_(2)管道输送过程中停输、水击、泄漏和放空工况下形成的CO_(2)瞬态流加以描述、成果比较和综合评价... 详细信息

长距离超临界CO_(2)管道瞬态输送的核心技术还有待突破,相关模型和方法亟需工业规模示范工程的验证及修正。以成就型综述法,对超临界CO_(2)管道输送过程中停输、水击、泄漏和放空工况下形成的CO_(2)瞬态流加以描述、成果比较和综合评价。结果表明:超临界CO_(2)瞬态流的关键因素是温度、压力、相态变化、协同作用;超临界CO_(2)管道安全停输时间可定义为从停输开始至管内任一点流体即将进入气液共存区的时间;CO_(2)发生相变首先造成流速突变,进而是压力的突变,产生水击现象,引起新的瞬变流动;站场放空系统的设计目标是在放空过程不出现冰堵、材料冷脆、噪声污染、放空系统激振等问题的前提下,放空时间尽量短;埋地管道泄漏规律涉及到土壤渗流场、温度场、浓度场等多场耦合问题。研究结果可为超临界CO_(2)管道流动安全保障提供参考。

关键词： CO_(2)管输瞬变特性停输再启动水击放空泄漏相变

2022年某国产儿童四价流感病毒裂解疫苗质量检测分析

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现代疾病预防控制 2024年第1期35卷 43-46页

作者：张勇朝韩斌董洁尚艳潘若文安文珏孙伟华兰生物疫苗股份有限公司河南新乡453003 河南省生物医药产业研究院

目的回顾评估某国产儿童四价流感病毒裂解疫苗关键质量指标,分析疫苗的有效性、安全性和批间一致性。方法以某国产公司生产的14批儿童四价流感病毒裂解疫苗为研究样品,检测样品血凝素含量、总蛋白含量、总蛋白/血凝素比值、卵清蛋白含... 详细信息

目的回顾评估某国产儿童四价流感病毒裂解疫苗关键质量指标,分析疫苗的有效性、安全性和批间一致性。方法以某国产公司生产的14批儿童四价流感病毒裂解疫苗为研究样品,检测样品血凝素含量、总蛋白含量、总蛋白/血凝素比值、卵清蛋白含量、细菌内毒素含量、游离甲醛含量,和企业注册标准、中国药典标准及WHO标准比较,同时计算标准差(s),评价产品质量。结果 14批儿童四价流感病毒裂解疫苗血凝素含量为31.9~35.9μg/m L(s 0.6~1.2)、总蛋白含量223.4~256.0μg/mL(s 9.0)、总蛋白/血凝素比值1.7~1.8(s 0.06)、卵清蛋白含量0.84~2.32 ng/mL(s 0.47)、细菌内毒素含量0.03~0.04 EU/mL(s 0.004)、游离甲醛含量2.05~2.70μg/mL(s 0.23),检测符合标准要求。结论该国产儿童四价流感病毒裂解疫苗14批产品检测结果均符合企业注册标准、中国药典标准及WHO标准,批间一致性好,产品具有良好的安全性和有效性。

关键词：儿童四价流感病毒裂解疫苗卵清蛋白细菌内毒素游离甲醛血凝素总蛋白

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大跨度混凝土钢筋框架梁挠度超限研究

建筑技术 2024年第3期55卷 322-324页

作者：张玉明尚彦宾边广生陈国斌山东建筑大学土木工程学院济南250101 山东建筑大学工程鉴定加固研究院有限公司济南250014 中铁十局集团城建工程有限公司山东烟台265500

根据大量的工程实践,大跨度钢筋混凝土框架梁由于设计不合理引起大跨度梁超限的工程案例很少,大多数是施工原因导致挠度超限。以某工程挠度超限的大跨度钢筋混凝土梁为例,根据设计资料和现场检测资料,从设计和施工两方面,利用数值计算... 详细信息

根据大量的工程实践,大跨度钢筋混凝土框架梁由于设计不合理引起大跨度梁超限的工程案例很少,大多数是施工原因导致挠度超限。以某工程挠度超限的大跨度钢筋混凝土梁为例,根据设计资料和现场检测资料,从设计和施工两方面,利用数值计算和有限元模拟,验证分析大跨度钢筋混凝土框架梁挠度超限的原因。验证分析表明,梁板混凝土实际浇筑厚度超限与梁模板起拱高度不足可能引起梁挠度增加。当梁下立杆稳定承载力不足时,梁也易随立杆屈曲变形产生较大挠度。

关键词：梁挠度模板起拱高度稳定承载力立杆屈曲

Application of Isogeometric Analysis Method in Three-Dimensional Gear Contact Analysis

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 817-846页

作者： Long Chen yan Yu yanpeng shang Zhonghou Wang Jing Zhang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai200093China Zhejiang Fine-Motion Robot Joint Technology Co. Ltd.Taizhou317600China

Gears are pivotal in mechanical drives,and gear contact analysis is a typically difficult problem to solve.Emerging isogeometric analysis(IGA)methods have developed new ideas to solve this problem.In this paper,a threedimensional body parametric gear model of IGA is established,and a theoretical formula is derived to realize single-tooth contact analysis.Results were benchmarked against those obtained from commercial software utilizing the finite element analysis(FEA)method to validate the accuracy of our approach.Our findings indicate that the IGA-based contact algorithmsuccessfullymet theHertz contact test.When juxtaposed with the FEA approach,the IGAmethod demonstrated fewer node degrees of freedomand reduced computational units,all whilemaintaining comparable accuracy.Notably,the IGA method appeared to exhibit consistency in analysis accuracy irrespective of computational unit density,and also significantlymitigated non-physical oscillations in contact stress across the tooth width.This underscores the prowess of IGA in contact analysis.In conclusion,IGA emerges as a potent tool for addressing contact analysis challenges and holds significant promise for 3D gear modeling,simulation,and optimization of various mechanical components.

关键词： Contact analysis involute gear isogeometric analysis finite element analysis

基于网络药理学探讨麻射安金丸治疗慢性阻塞性肺疾病的作用机制

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世界中西医结合杂志 2024年第3期19卷 542-549页

作者：尚艳花邓敬华张晓阳马真王玉栋衡水市中医医院河北衡水053000

目的基于网络药理学分析麻射安金丸治疗慢性阻塞性肺疾病(Chronic obstructive pulmonary disease,COPD)的潜在机制。方法应用TCMSP中药系统药理学数据库及相关文献资料等检索麻射安金丸中的生物活性成分,筛选出作用靶点,构建麻射安金... 详细信息

目的基于网络药理学分析麻射安金丸治疗慢性阻塞性肺疾病(Chronic obstructive pulmonary disease,COPD)的潜在机制。方法应用TCMSP中药系统药理学数据库及相关文献资料等检索麻射安金丸中的生物活性成分,筛选出作用靶点,构建麻射安金丸的药物-有效成分-作用靶点网络。根据Drugbank和Genecards等数据库建立其与COPD的相关疾病靶点,并与麻射安金丸的有效成分靶点相匹配获得潜在治疗靶点。基于Metascape数据库和DAVID数据库对潜在治疗靶点进行GO生物过程、KEGG信号通路分析,并分析蛋白质-蛋白质相互作用(Protein-protein interaction,PPI),用Cytoscape软件对PPI网络进行拓扑分析。结果麻射安金丸中有效化学成分有1525种,包括半夏22种、赤芍18种、川芎22种、甘草95种、僵蚕3种、苦杏仁26种、麻黄43种、牡蛎1种、木香29种、砂仁23种、射干12种和浙贝母5种,有效成分作用靶点基因298个。在药物-有效成分-靶点网络内重要性前10的有效成分中,来源自麻黄6种,赤芍、苦杏仁、僵蚕3种,射干、甘草、半夏、川芎、砂仁2种,浙贝母1种。KEGG富集分析显示,在得出的全部20调信号通路中,得到10条靠前的信号通路。GO功能富集分析显示,前10个生物过程包括酶结合、DNA依赖的转录正调控等;前10个分子功能包括核质、细胞质等;前10个细胞定位包括蛋白质变性调节、蛋白质代谢调节等。PPI网络经提取后获得了包含21个节点的核心网络,其中JUN、MAPK1、MAPK3、TNF、RELA、MYC、STAT3、TP53、AKT1、MAPK8、EGFR、MAPK14和PRKCA基因是核心靶点。动物实验显示:模型组和对照组大鼠血清IL-1β、IL-6和TNF-α均高于空白组,差异有统计学意义(P<0.05);模型组大鼠血清IL-1β、IL-6和TNF-α均低于对照组,差异有统计学意义(P<0.05)。模型组和对照组大鼠MAPK1、MAPK3、MYC的mRNA表达水平均高于空白组,差异有统计学意义(P<0.05);模型组大鼠MAPK1、MAPK3、MYC的mRNA表达水平均低于对照组,差异有统计学意义(P<0.05)。结论麻射安金丸通过多成分、多靶点和多通路治疗COPD,其中麻射安金丸的潜在有效成分主要来源于麻黄、射干、柴胡、白芍、白术和甘草,麻射安金丸治疗作用的核心靶点主要有JUN、MAPK1、MAPK3等基因。

关键词：麻射安金丸慢性阻塞性肺疾病网络药理学基因核心靶点

High-precision parallel computing model of solute transport based on GPU acceleration

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Journal of Hydrodynamics 2024年第1期36卷 202-212页

作者： shang-hong Zhang Rong-qi Zhang Wen-da Li Xi-yan yang yang Zhou School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing102206China Hubei Key Laboratory of Intelligent yangtze and Hydroelectric Science China Yangtze Power Co.Ltd.Yichang443133China

The scenario simulation analysis of water environmental emergencies is very important for risk prevention and control,and emergency response.To quickly and accurately simulate the transport and diffusion process of high-intensity pollutants during sudden environmental water pollution events,in this study,a high-precision pollution transport and diffusion model for unstructured grids based on Compute Unified Device Architecture(CUDA)is proposed.The finite volume method of a total variation diminishing limiter with the Kong proposed r-factor is used to reduce numerical diffusion and oscillation errors in the simulation of pollutants under sharp concentration conditions,and graphics processing unit acceleration technology is used to improve computational efficiency.The advection diffusion process of the model is verified numerically using two benchmark cases,and the efficiency of the model is evaluated using an engineering example.The results demonstrate that the model perform well in the simulation of material transport in the presence of sharp concentration.Additionally,it has high computational efficiency.The acceleration ratio is 46 times the single-thread acceleration effect of the original model.The efficiency of the accelerated model meet the requirements of an engineering application,and the rapid early warning and assessment of water pollution accidents is achieved.

关键词： Pollution transport and diffusion model parallel computing Compute Unified Device Architecture(CUDA) pollution event

Large-scale synthesis of low-cost 2D metal–organic frameworks for highly selective photocatalytic CO_(2)reduction

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Nano Research 2023年第5期16卷 7756-7760页

作者： Ning-Yu Huang Zhen-Yu Chen Fei-Long Hu Chun-yan shang Wenjuan Wang Jia-Run Huang Chuan Zhou Lei Li Qiang Xu Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) Southern University of Science and TechnologyShenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL) Southern University of Science and TechnologyShenzhen 518055China Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275China

Two-dimensional metal–organic frameworks(2D MOFs),as a new type of 2D materials,have been widely applied in various applications because of their unique structures and exposed active sites.Herein,we reported two low-cost 2D MOFs constructed by a raw chemical succinic acid(SA),M-SA(M=Ni or Co),which served as efficient photocatalysts for the reduction of CO_(2)to CO.Taking advantage of the thinness and open metal sites,the ultrathin Ni-SA nanosheets(ca.3.6 nm)exhibited excellent CO production of 6.96(7)mmol·g^(−1)·h^(−1)and CO selectivity of 96.6%.Photoelectrochemical tests and theoretical calculations further confirmed the higher charge transfer efficiency and unsaturated metal sites for promoting photocatalytic performances.More importantly,Ni-SA can also be synthesized in large-scale by an energy-saving method under room temperature,strongly suggesting its promising future and potential for practical applications.

关键词： two-dimensional metal–organic framework low-cost photocatalysis CO_(2)reduction large-scale synthesis