期刊文献+
共找到2,874篇文章
< 1 2 144 >
每页显示 20 50 100
Research on the Reform and Practice of Basic Nursing Teaching Model Based on the OBE Concept
1
作者 Qi Mai 《Journal of Contemporary Educational Research》 2025年第1期86-91,共6页
In response to current issues in basic nursing course instruction,this article proposes a teaching model reform based on the OBE(outcome-based education)concept.By resetting course objectives,innovating teaching metho... In response to current issues in basic nursing course instruction,this article proposes a teaching model reform based on the OBE(outcome-based education)concept.By resetting course objectives,innovating teaching methods and content,reforming the assessment and evaluation system,as well as conducting practical explorations and case studies,the aim is to enhance teaching quality and cultivate students’practical abilities and comprehensive qualities.The article elaborates on the application of the OBE concept in nursing education and its effectiveness evaluation,providing a valuable reference for nursing education reform. 展开更多
关键词 OBE concept basic nursing course Teaching model reform Practical ability Comprehensive quality
在线阅读 下载PDF
A Study on the Work Process-Based Practical Training Model for Basic Nursing Skills in Vocational Colleges
2
作者 Dan Li Huan Wei 《Journal of Clinical and Nursing Research》 2024年第9期128-132,共5页
Objective:To explore and analyze the work process-based practical training teaching model for basic nursing skills in vocational colleges and its implementation effects.Methods:A total of 82 nursing students from our ... Objective:To explore and analyze the work process-based practical training teaching model for basic nursing skills in vocational colleges and its implementation effects.Methods:A total of 82 nursing students from our school were selected for the study,which was conducted from April 2023 to April 2024.Using a random number table method,the students were divided into an observation group and a control group,each with 41 students.The control group received conventional practical training teaching,while the observation group followed the work process-based practical training model for basic nursing skills.The assessment scores and teaching satisfaction of the two groups were compared.Results:The comparison of assessment scores showed that the observation group performed significantly better than the control group(P<0.05).The comparison of teaching satisfaction also indicated that the observation group had significantly higher satisfaction than the control group(P<0.05).Conclusion:The work process-based practical training teaching model for basic nursing skills in vocational colleges can improve students’assessment scores and enhance teaching satisfaction,demonstrating its value for wider application. 展开更多
关键词 Work processes Vocational colleges basic nursing skills Practical training teaching model
在线阅读 下载PDF
A Reaction-Diffusion SIR Model with Saturated Incidence Rate and Vaccination
3
作者 Shaoyi Geng Xiaolin Lin +1 位作者 Danfeng Pang Guoqing Li 《Journal of Applied Mathematics and Physics》 2025年第2期400-418,共19页
In this paper, we establish an SIR reaction-diffusion infectious disease model with saturated incidence rate and vaccination. Firstly, we prove the uniform boundedness of the solution of this model. Secondly, we estab... In this paper, we establish an SIR reaction-diffusion infectious disease model with saturated incidence rate and vaccination. Firstly, we prove the uniform boundedness of the solution of this model. Secondly, we establish the threshold dynamic behavior of the model based on the basic reproduction number R0, specifically, we prove the globally asymptotic stability of the disease-free equilibrium and the uniform persistence of the model. Thirdly, we show the existence and stability of the endemic equilibrium of the homogeneous system and obtain different cases of positive solution. Fourthly, we investigate the effects of vaccination rate and saturated incidence rate on the basic reproduction number. The results indicate that increasing vaccination rate and saturation rate can effectively control the transmission of the disease. Finally, we conduct numerical simulations to verify the aforementioned conclusions. 展开更多
关键词 Reaction-Diffusion model Saturated Incidence Rate basic Reproduction Number Threshold Dynamics Asymptotic Profile
在线阅读 下载PDF
Basic Soil Productivity of Spring Maize in Black Soil Under Long-Term Fertilization Based on DSSAT Model 被引量:26
4
作者 ZHA Yan WU Xue-ping +5 位作者 HE Xin-hua ZHANG Hui-min GONG Fu-fei CAI Dian-xiong ZHU Ping GAO Hong-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期577-587,共11页
Increasing basic farmland soil productivity has significance in reducing fertilizer application and maintaining high yield of crops. In this study, we defined that the basic soil productivity (BSP) is the production... Increasing basic farmland soil productivity has significance in reducing fertilizer application and maintaining high yield of crops. In this study, we defined that the basic soil productivity (BSP) is the production capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local environment and field management. Based on 22-yr (1990-2011) long-term experimental data on black soil (Typic hapludoll) in Gongzhuling, Jilin Province, Northeast China, the decision support system for an agro-technology transfer (DSSAT)-CERES-Maize model was applied to simulate the yield by BSP of spring maize (Zea mays L.) to examine the effects of long-term fertilization on changes of BSP and explore the mechanisms of BSP increasing. Five treatments were examined: (1) no-fertilization control (control); (2) chemical nitrogen, phosphorus, and potassium (NPK); (3) NPK plus farmyard manure (NPKM); (4) 1.5 time of NPKM (1.5NPKM) and (5) NPK plus straw (NPKS). Results showed that after 22-yr fertilization, the yield by BSP of spring maize significantly increased 78.0, 101.2, and 69.4% under the NPKM, 1.5NPKM and NPKS, respectively, compared to the initial value (in 1992), but not significant under NPK (26.9% increase) and the control (8.9% decrease). The contribution percentage of BSP showed a significant rising trend (P〈0.05) under 1.5NPKM. The average contribution percentage of BSP among fertilizations ranged from 74.4 to 84.7%, and ranked as 1.5NPKM〉NPKM〉NPK〉NPKS, indicating that organic manure combined with chemical fertilizers (I.5NPKM and NPKM) could more effectively increase BSP compared with the inorganic fertilizer application alone (NPK) in the black soil. This study showed that soil organic matter (SOM) was the key factor among various fertility factors that could affect BSP in the black soil, and total N, total P and/or available P also played important role in BSP increasing. Compared with the chemical fertilization, a balanced chemical plus manure or straw fertilization (NPKM or NPKS) not only increased the concentrations of soil nutrient, but also improved the soil physical properties, and structure and diversity of soil microbial population, resulting in an iincrease of BSP. We recommend that a balanced chemical plus manure or straw fertilization (NPKM or NPKS) should be the fertilization practices to enhance spring maize yield and improve BSP in the black soil of Northeast China. 展开更多
关键词 spring maize long-term fertilization basic soil productivity black soil DSSAT model
在线阅读 下载PDF
LAGFD-WAM numerical wave model-Ⅰ. Basic physical model 被引量:48
5
作者 Yuan Yeli, Hua Feng, Pan Zengdi Sun Letao First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第4期483-488,共6页
The LAGFD-WAM wave model is a third generation wave model. In the present paper the physical aspect of the model was shown in great detail including energy spectrum balance equation, complicated characteristics equati... The LAGFD-WAM wave model is a third generation wave model. In the present paper the physical aspect of the model was shown in great detail including energy spectrum balance equation, complicated characteristics equations and source functions. 展开更多
关键词 WAVE LAGFD-WAM numerical wave model basic physical model WAM
在线阅读 下载PDF
The effect of basic fibroblast growth factor on regeneration in a surgical wound model of rat submandibular glands 被引量:4
6
作者 Fumitaka Kobayashi Kenichi Matsuzaka Takashi Inoue 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第1期16-23,共8页
This study developed an animal model of surgically wounded submandibular glands (SMGs) and investigated the effects of collagen gel with basic fibroblast growth factor (bFGF) on tissue regeneration of surgically w... This study developed an animal model of surgically wounded submandibular glands (SMGs) and investigated the effects of collagen gel with basic fibroblast growth factor (bFGF) on tissue regeneration of surgically wounded SMGs in vivo. The animal model was produced by creating a surgical wound using a 3-mm diameter biopsy punch in SMGs. The wound was filled with collagen gel with bFGF (bFGF group) or without bFGF (control group). In the animal model of surgically wounded SMGs, salivary glands without scar tissue around the wound area were observed with smaller areas of collagen gel. Small round and spindle-shape cells invaded the collagen gel in both groups after operation day (AOD) 5, and this invasion dramatically increased at AOD 7. Host tissue completely replaced the collagen gel at AOD 21. The invading immune cells in the group treated with collagen gel with bFGF were positive for vimentin, g-smooth muscle actin (αSMA), CD49f, c-kit and AQP5 at AOD 7. Similarly, the mRNA expression of vimentin, αSMA, CD49f, keratin 19 and AQP5 was also increased. This study suggests that the use of collagen gels with bFGF improves salivary gland regeneration. 展开更多
关键词 animal model basic fibroblast growth factor COLLAGEN IMMUNOHISTOCHEMISTRY salivary gland wound healing
在线阅读 下载PDF
A model for estimating the rate constant between CO_2-CO gas and molten slag containing iron oxides using optical basicity 被引量:1
7
作者 Teng Zhang Xiao-jun Hu +1 位作者 Qi-feng Shu Kuo-Chih Chou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第8期685-688,共4页
A simple model for estimating the rate constant between CO2-CO gas and molten slag containing iron oxides was developed using optical basicity only. In this model, the temperature dependence of the rate constant can b... A simple model for estimating the rate constant between CO2-CO gas and molten slag containing iron oxides was developed using optical basicity only. In this model, the temperature dependence of the rate constant can be described by the Arrhenius law, and the activation energy can be expressed with a linear function of the slag's optical basicity. The model was applied to some molten slag systems, such as FeO, FeO-CaO, FeO-SiO2, FeO-Na2O, FeO-CaO-SiO2, FeO-SiO2-P2O5, FeO-SiOE-Na2O, and FeO-CaO-SiOE-P2O5. A comparison between the predicted results and measured data showed that the model worked well. 展开更多
关键词 SMELTING rate constants SLAG iron oxides optical basicity modelS
在线阅读 下载PDF
SEIHCRD Model for COVID-19 Spread Scenarios,Disease Predictions and Estimates the Basic Reproduction Number,Case Fatality Rate,Hospital,and ICU Beds Requirement 被引量:1
8
作者 Avaneesh Singh Manish Kumar Bajpai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第12期991-1031,共41页
We have proposed a new mathematical method,the SEIHCRD model,which has an excellent potential to predict the incidence of COVID-19 diseases.Our proposed SEIHCRD model is an extension of the SEIR model.Three-compartmen... We have proposed a new mathematical method,the SEIHCRD model,which has an excellent potential to predict the incidence of COVID-19 diseases.Our proposed SEIHCRD model is an extension of the SEIR model.Three-compartments have added death,hospitalized,and critical,which improves the basic understanding of disease spread and results.We have studiedCOVID-19 cases of six countries,where the impact of this disease in the highest are Brazil,India,Italy,Spain,the United Kingdom,and the United States.After estimating model parameters based on available clinical data,the modelwill propagate and forecast dynamic evolution.Themodel calculates the Basic reproduction number over time using logistic regression and the Case fatality rate based on the selected countries’age-category scenario.Themodel calculates two types of Case fatality rate one is CFR daily,and the other is total CFR.The proposed model estimates the approximate time when the disease is at its peak and the approximate time when death cases rarely occur and calculate how much hospital beds and ICU beds will be needed in the peak days of infection.The SEIHCRD model outperforms the classic ARXmodel and the ARIMA model.RMSE,MAPE,andRsquaredmatrices are used to evaluate results and are graphically represented using Taylor and Target diagrams.The result shows RMSE has improved by 56%–74%,and MAPE has a 53%–89%improvement in prediction accuracy. 展开更多
关键词 COVID-19 CORONAVIRUS SIER model SEIHCRD model parameter estimation mathematical model India Brazil United Kingdom United States Spain Italy hospital beds ICU beds basic reproduction number case fatality rate
在线阅读 下载PDF
Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network 被引量:4
9
作者 Xin Shao Qing Liu +3 位作者 Zicheng Xin Jiangshan Zhang Tao Zhou Shaoshuai Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期106-117,共12页
The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based ... The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter. 展开更多
关键词 basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model
在线阅读 下载PDF
NONLINEAR SATURATION OF BAROCLINIC INSTABILITY IN THE GENERALIZED PHILLIPS MODEL(Ⅱ)- THE LOWER BOUND ON THE DISTURBANCE ENERGY AND POTENTIAL ENSTROPHY TO THE NONLINEARLY UNSTABLE BASIC FLOW
10
作者 ZHANG Gui(张瑰) +1 位作者 XIANG Jie(项杰) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1339-1347,共9页
On the basis of the nonlinear stability theorem in the context of Arnol'd's second theorem for the generalized Phillips model,nonlinear saturation of baroclinic instability in the generalized Phillips model is... On the basis of the nonlinear stability theorem in the context of Arnol'd's second theorem for the generalized Phillips model,nonlinear saturation of baroclinic instability in the generalized Phillips model is investigatedThe lower bound on the disturbance energy and potential enstrophy to the nonlinearly unstable basic flow in the generalized Phillips model is presented,which indicates that there may exist an allocation between a nonlinearly unstable basic flow and a growing disturbance 展开更多
关键词 nonlinear saturation baroclinic instability generalized Phillips model basic flow
在线阅读 下载PDF
AN ADSORB MODEL OF ORGANIC ACID ON BASIC ZEOLITE NAX
11
作者 Ming SU Ke Yi TAO +1 位作者 Ling Ping ZHOU He Xuan LI(Department of Chemistry, Nankai University, Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第8期743-744,共2页
The adsorb model of formic acid on NaX derived from TPD was discussed. It was showed that the adsorb sites were various exposed framework O2- centers bearing different basic intensity and spatial resistance. The h-pea... The adsorb model of formic acid on NaX derived from TPD was discussed. It was showed that the adsorb sites were various exposed framework O2- centers bearing different basic intensity and spatial resistance. The h-peak was attributed to O2- near S-III in supercage and l-peak to O2- near S-II in beta-cage of faujusite zeolite. The model can explain the experimental results. Meanwhile, a relative standard of basic intensity based on TPD of formic acid was founded. 展开更多
关键词 ACID basic AN ADSORB model OF ORGANIC ACID ON basic ZEOLITE NAX
在线阅读 下载PDF
Research on the Education Model of "Curriculum Ideological and Political Theory" in Basic Courses
12
作者 LIJinkui 《外文科技期刊数据库(文摘版)教育科学》 2022年第3期146-150,共5页
Speeding up the promotion of the basic course "Curriculum Ideological and Political Theory" is a kind of teaching idea and practical innovation to implement the important speech spirit of General Secretary X... Speeding up the promotion of the basic course "Curriculum Ideological and Political Theory" is a kind of teaching idea and practical innovation to implement the important speech spirit of General Secretary Xi Jinping on strengthening ideological and political education. This paper analyzes the main and difficult problems existing in the current teaching reform of "course ideological and political theory" in basic courses, and combines with the teaching practice of "basic courses" in our school to promote the course ideological and political theory, digs deep into the ideological and political elements contained in basic courses, and constructs two "five in one" ideological and political education modes. 展开更多
关键词 basic courses ideological and political theory of the course educational model
在线阅读 下载PDF
基于CNCSCOLOR的色相-色调感性模型构建
13
作者 薛媛 白圆圆 姜茸凡 《丝绸》 CAS 北大核心 2025年第1期1-10,共10页
中国应用色彩体系(CNCSCOLOR)基于中国人眼视觉实验所开发,但在国外色彩体系的早期市场占有下没有得到广泛应用。本研究尝试开发一套易于学习推广的模型,以促进其普及和应用。首先通过对三维色彩体系的研究分析,借鉴日本PCCS色彩体系,... 中国应用色彩体系(CNCSCOLOR)基于中国人眼视觉实验所开发,但在国外色彩体系的早期市场占有下没有得到广泛应用。本研究尝试开发一套易于学习推广的模型,以促进其普及和应用。首先通过对三维色彩体系的研究分析,借鉴日本PCCS色彩体系,构建了简化的二维色相-色调基本模型,其中色调融合了色彩属性明度和彩度。模型用直角坐标定位,水平轴为彩度,垂直轴为明度,5种无彩色将明度轴分为四段,12个20色色相环即12种有彩色色调,按照明度与彩度的大小有序分布于平面内。确定构成基本模型的240种有彩色和5种无彩色的选色规则,选出色彩,组合完善基本模型。其次,研究确定12种有彩色色调的感性,得到色相-色调感性模型。通过主观调查初步分析得到有彩色色调的感性,再实施客观眼动实验进一步验证调查结果,最终确定12个有彩色色调的感性分别是鲜明的、明快的、强烈的、浑厚的、清新的、淡雅的、浑浊的、厚重的、浅淡的、暗淡的、灰暗的、黑暗的。研究得到的色相-色调模型包含的色彩数量少,采用二维的平面布局,使初学者易懂易记,便于普及应用;且色调命名符合中国人的情感特征,将用于后续的感性配色模型构建,便于设计师和消费者快速进行精准的产品色彩搭配,对中国本土色彩体系的发展和色彩设计水平的提升具有实际的应用价值。 展开更多
关键词 CNCSCOLOR PCCS色彩体系 色相-色调基本模型 色相-色调感性模型 主观调查 眼动实验
在线阅读 下载PDF
Global Stability and Bifurcation Analysis of a Cholera Transmission Model
14
作者 Liu Qiumei Liu Lingling Xu Fang 《数学理论与应用》 2024年第4期70-87,共18页
This paper investigates the stability and bifurcation phenomena of a cholera transmission model in which individuals who have recovered from the disease may become susceptible again.The threshold for determining disea... This paper investigates the stability and bifurcation phenomena of a cholera transmission model in which individuals who have recovered from the disease may become susceptible again.The threshold for determining disease prevalence is established,and the parameter conditions for the existence of equilibria are discussed.The Routh-Hurwitz criterion is applied to demonstrate the local asymptotic stability of equilibria.By utilizing composite matrices and geometric techniques,the global dynamic behavior of the endemic equilibrium is investigated,and the sufficient conditions for its global asymptotic stability are derived.Furthermore,the disease-free equilibrium is a saddle-node when the basic reproductive number is 1,and tthe transcritical bifurcation in this case is discussed. 展开更多
关键词 Cholera model basic reproductive number Global asymptotic stability Saddle-node Transcritical bifurcation
在线阅读 下载PDF
基于人工智能模拟的社区公园布局基础要素对空间公平的影响研究
15
作者 刘志强 诸逸凡 +1 位作者 洪亘伟 余慧 《中国园林》 北大核心 2025年第2期48-54,共7页
社区公园是与居民联系最为紧密的社区级公共绿色空间,实现其布局空间公平是推进基本公共服务均等化的重要需求。基于人工智能方法,从整体差异、区域间差异和分配差异选取评价指标,构筑数量、区位和面积的组合模式,量化分析三基础要素及... 社区公园是与居民联系最为紧密的社区级公共绿色空间,实现其布局空间公平是推进基本公共服务均等化的重要需求。基于人工智能方法,从整体差异、区域间差异和分配差异选取评价指标,构筑数量、区位和面积的组合模式,量化分析三基础要素及其组合对社区公园布局空间公平的影响,经由姑苏区案例验证模拟结果。结果表明,社区公园布局由“少而大”转为“多而小”,3种要素在不同的空间公平层级产生影响:1)数量要素关联社区公园覆盖率以影响整体差异,整体差异共降低57.60%;2)区位要素改变居民与社区公园空间关系以影响区域间差异,区域间差异共降低59.41%;3)面积要素调整供需关系以影响分配差异,分配差异共降低44.32%;4)姑苏区社区公园布局的基础要素对空间公平的影响遵循上述模拟规律,但整体差异与分配差异变化更显著,而区域间差异变化则相对较小。揭示了社区公园布局基础要素对空间公平的影响规律,为落实社区公园布局空间公平理念提供支撑,为其规划优化提供精准化指引。 展开更多
关键词 风景园林 社区公园布局 基础要素 空间公平 人工智能模拟
在线阅读 下载PDF
人工智能大模型对档案学基础理论的挑战及其回应
16
作者 徐拥军 陈晓婷 闫静 《图书情报知识》 北大核心 2025年第1期57-69,共13页
[目的/意义]人工智能大模型对档案学基础理论带来挑战和变革,亟需探讨其如何推动档案学基础理论的创新与发展。[研究设计/方法]通过对比传统时代和人工智能时代档案学基础理论的内容要点,阐述档案学基础理论对大模型挑战的回应,进一步... [目的/意义]人工智能大模型对档案学基础理论带来挑战和变革,亟需探讨其如何推动档案学基础理论的创新与发展。[研究设计/方法]通过对比传统时代和人工智能时代档案学基础理论的内容要点,阐述档案学基础理论对大模型挑战的回应,进一步解释“大模型如何影响档案学基础理论?而档案学基础理论又应当如何回应大模型发起的挑战?”[结论/发现]大模型对档案学基础理论提出了来源原则概念狭窄,文件生命周期延伸、档案价值转化,档案鉴定理论缺失可信性、销而不毁,档案记忆观的建构主体危机等挑战。为回应这些挑战,档案学基础理论需进行自我调适和创新:新来源观概念与背景的再发现,强调文件生命周期的动态连续性,关注档案鉴定理论的可信度检测与被遗忘权,规范算法权力和掌握记忆话语权。[创新/价值]从理论层面重新审视大模型对档案学基础理论的挑战,以及档案学基础理论应如何进行自我修正以做出恰当回应,切实为人工智能时代的档案工作提供理论指导。 展开更多
关键词 人工智能 大模型 档案学基础理论 档案工作
在线阅读 下载PDF
基于动物模型的系统评价大柴胡汤对胆汁淤积的效果及作用机制
17
作者 姜德龙 张展 +1 位作者 王庆谚 许斌 《世界中医药》 北大核心 2025年第2期259-265,共7页
目的:综合评价大柴胡汤(DCHD)对不同类型胆汁淤积动物模型的效果及作用机制。方法:系统检索Pubmed、Cochrane Library、Embase、国家知识基础设施数据库(CNKI)、中国学术期刊数据库(CSPD)、中文科技期刊数据库(CCD)等数据库,检索时限为... 目的:综合评价大柴胡汤(DCHD)对不同类型胆汁淤积动物模型的效果及作用机制。方法:系统检索Pubmed、Cochrane Library、Embase、国家知识基础设施数据库(CNKI)、中国学术期刊数据库(CSPD)、中文科技期刊数据库(CCD)等数据库,检索时限为建库至2023年4月30日,纳入已公开发表的DCHD干预胆汁淤积的动物研究文献;由2名研究员独立筛选报告和相关数据提取,并应用动物实验偏倚评估量表(SYRLE)和定性研究证据的质量评价与分级量表(GRADE-CERQual)评估纳入研究的偏倚风险和证据质量。结果:纳入15项动物实验研究。除1项研究报告了DCHD不能缓解肝外胆道结扎(BDL)所致胆汁淤积,其余研究均报告了DCHD作用于不同类型胆汁淤积模型的有效性,且肝外模型的动物基础研究中的证据支持高于肝内模型;在整合DCHD作用机制过程中,“炎症”质量评级为高级,“胆汁酸稳态”和“凋亡”质量评级为中级,“氧化应激”“肠黏膜屏障”“内质网应激”为质量评级为低级。结论:DCHD在不同类型的胆汁淤积动物模型中具有减轻肝损伤和缓解胆汁淤积的作用,在肝外模型的作用证据支撑相对较高;在机制方面,改善炎症的质量等级相对较高,而在调控胆汁酸稳态、凋亡、氧化应激、肠黏膜损伤及内质网应激方面的质量评级相对较低。 展开更多
关键词 胆汁淤积 大柴胡汤 动物模型 机制研究 系统综述 质量评价 基础研究 定性研究
在线阅读 下载PDF
数据要素价值释放机制与框架
18
作者 奉国和 邱婧 《深圳社会科学》 2025年第1期47-62,共16页
科学合理的数据要素价值释放体系是推进数字经济、数字中国与数字社会发展,提升新质生产力的基础。基于DIKW模型从数据、信息、知识和智慧的演变逻辑,厘清数据要素价值释放内在机理及难点,围绕“释放数据要素价值,助力新质生产力发展”... 科学合理的数据要素价值释放体系是推进数字经济、数字中国与数字社会发展,提升新质生产力的基础。基于DIKW模型从数据、信息、知识和智慧的演变逻辑,厘清数据要素价值释放内在机理及难点,围绕“释放数据要素价值,助力新质生产力发展”核心目标,提出“两基础”“三驱动”“四保障”“五途径”基本体系,构建数据要素价值释放多层次框架。其中,“两基础”指数据要素制度体系和数据要素系统设施;“三驱动”涉及供给侧、场内外交易和需求侧;“四保障”强调提升数据质量、加强安全监管、保护数据权益、促进数据流通交易;“五途径”指从数据资源化、数据资产化、数据资本化、数据普惠化到数据均等化,展示数据价值释放的多元路径。通过DIKW模型,数据在从数据到信息、再到知识与智慧的转化过程中,不仅实现价值创造,还通过系统的治理与分析机制,推动价值实现与价值倍增。最终,通过一个核心、两大基础、三大驱动、四维保障和五条途径的多层次框架,实现数据要素价值的高效释放。框架从支撑体系、动力体系、保障体系及转化体系等维度体现数据要素价值释放的作用与机制,保障数据要素价值有效释放,有助于推动新质生产力的发展,为数字经济、数字中国与数字社会长远发展奠定坚实基础。 展开更多
关键词 数据要素 DIKW模型 价值释放 新质生产力 基本框架
在线阅读 下载PDF
一类具有隔离和消毒剂影响的霍乱模型研究
19
作者 刘慧 乔志琴 《中北大学学报(自然科学版)》 2025年第2期261-270,共10页
本文建立了一个考虑隔离和消毒剂影响的霍乱传染病模型,探究了这些因素对霍乱传播动态的影响。运用微分方程理论描述了模型的传播动力学,使用下一代矩阵法对模型的基本再生数进行了计算。在此基础上,详细阐述了无病平衡点和地方病平衡... 本文建立了一个考虑隔离和消毒剂影响的霍乱传染病模型,探究了这些因素对霍乱传播动态的影响。运用微分方程理论描述了模型的传播动力学,使用下一代矩阵法对模型的基本再生数进行了计算。在此基础上,详细阐述了无病平衡点和地方病平衡点的存在性和局部渐近稳定性,并对各平衡点处的全局渐近稳定性进行了深入讨论。结果显示,当基本再生数R_(0)<1时,模型的无病平衡点具有全局渐近稳定性;而当基本再生数R_(0)>1时,得出了地方病平衡点全局渐近稳定的充分条件。此外,采用PRCC法进行了敏感性分析,模拟隔离率和消毒剂对感染者和霍乱弧菌密度的影响,使用数值模拟验证了理论结果的正确性。对具有隔离和消毒剂双重控制策略影响下的霍乱传染病模型的研究表明,多重控制策略能够更加有效地抑制霍乱的传播。 展开更多
关键词 霍乱模型 基本再生数 稳定性 平衡点
在线阅读 下载PDF
PSR模型在青海省生态安全评价中的应用
20
作者 李小玲 刘逸瑞 +1 位作者 王成 保长佩 《安全与环境学报》 北大核心 2025年第2期757-766,共10页
为了对青海省的生态安全水平进行定量评价,分析并认识青海省生态状况及其影响因素,进而为生态工作提供相应方向和措施,研究基于“压力-状态-响应”(Pressure-State-Response,PSR)模型构建青海省生态安全评价体系,采用熵权法计算指标权重... 为了对青海省的生态安全水平进行定量评价,分析并认识青海省生态状况及其影响因素,进而为生态工作提供相应方向和措施,研究基于“压力-状态-响应”(Pressure-State-Response,PSR)模型构建青海省生态安全评价体系,采用熵权法计算指标权重,运用综合指数法评价分析青海省生态安全的状况,并采用灰色关联度法和障碍度模型,分析影响青海省生态安全的关键因素。结果显示:(1)青海省生态安全指数整体呈现“波浪式”上升趋势,安全等级由较不安全等级逐年上升至较安全等级。(2)从关联度来看,在子系统中,状态子系统占主要地位。在各评价指标中,影响青海省生态安全的因素主要集中于经济和环境维度。(3)从障碍度来看,目前阻碍青海省生态安全发展的障碍因子主要为造林面积、治理废气项目完成投资、二氧化硫排放量等要素。在2005—2020年,青海省生态安全水平显著提高,但仍有提升空间。政府需积极落实政策,发展绿色产业,保护生态环境,实现走可持续发展道路。 展开更多
关键词 环境科学技术基础学科 生态安全 综合指数法 灰色协调度法 障碍度模型
在线阅读 下载PDF
上一页 1 2 144 下一页 到第
使用帮助 返回顶部