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Modeling Study of Aerosol Indirect Effectson Global Climate with an AGCM 被引量:4
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作者 王志立 张华 +2 位作者 沈学顺 龚山陵 张小曳 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1064-1077,共14页
Aerosol indirect effects (AIEs) on global climate were quantitatively investigated by introducing aerosol–cloud interaction parameterizations for water stratus clouds into an AGCM (BCC AGCM2.0.1), which was devel... Aerosol indirect effects (AIEs) on global climate were quantitatively investigated by introducing aerosol–cloud interaction parameterizations for water stratus clouds into an AGCM (BCC AGCM2.0.1), which was developed by the National Climate Center of the China Meteorological Administration. The study yielded a global annual mean of -1.14 W m^-2 for the first indirect radiative forcing (IRF), with an obvious seasonal change. In summer, large forcing mainly occurred in mid to high latitudes of the Northern Hemisphere, whereas in winter, large values were found at 60°S. The second indirect effect led to global annual mean changes in net shortwave flux of -1.03 W m^-2 at the top of the atmosphere (TOA), which was relatively significant in mid-latitude regions of both hemispheres. The total AIE reduced the global annual means of net shortwave flux at the TOA and of surface temperature by 1.93 W m^-2 and 0.12 K, respectively. Change in surface temperature induced by the total AIE was clearly larger in the Northern Hemisphere (-0.23 K) than in the Southern Hemisphere, where changes were negligible. The interhemispheric asymmetry in surface cooling resulted in significant differences in changes of the interhemispheric annual mean precipitation rate, which could lead to a tendency for the ITCZ to broaden. The total AIE decreased the global annual mean precipitation rate by 0.055 mm df^-1. 展开更多
关键词 AEROSOL CLOUD RADIATION indirect effect
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First Surface-based Estimation of the Aerosol Indirect Effect over a Site in Southeastern China 被引量:2
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作者 Jianjun LIU Zhanqing LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第2期169-181,共13页
The deployment of the U.S. Atmospheric Radiation Measurement mobile facility in Shouxian from May to December 2008 amassed the most comprehensive set of measurements of atmospheric, surface, aerosol, and cloud variabl... The deployment of the U.S. Atmospheric Radiation Measurement mobile facility in Shouxian from May to December 2008 amassed the most comprehensive set of measurements of atmospheric, surface, aerosol, and cloud variables in China. This deployment provided a unique opportunity to investigate the aerosol-cloud interactions, which are most challenging and, to date, have not been examined to any great degree in China. The relationship between cloud droplet effective radius (CER) and aerosol index (AI) is very weak in summer because the cloud droplet growth is least affected by the competition for water vapor. Mean cloud liquid water path (LWP) and cloud optical depth (COD) significantly increase with increasing AI in fall. The sensitivities of CER and LWP to aerosol loading increases are not significantly different under different air mass conditions. There is a significant correlation between the changes in hourly mean AI and the changes in hourly mean CER, LWP, and COD. The aerosol first indirect effect (FIE) is estimated in terms of relative changes in both CER (FIEcER) and COD (FIEcoD) with changes in AI for different seasons and air masses. FIEcoD and FIEcER are similar in magnitude and close to the typical FIE value of - 0.23, and do not change much between summer and fall or between the two different air mass conditions. Similar analyses were done using spaceborne Moderate Resolution Imaging Spectroradiometer data. The satellite-derived FIE is contrary to the FIE estimated from surface retrievals and may have large uncertainties due to some inherent limitations. 展开更多
关键词 ground-based measurements aerosol indirect effect southeastern China
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Modeling of the Second Indirect Effect of Anthropogenic Aerosols in East Asia 被引量:2
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作者 WU Peng-Ping HAN Zhi-Wei 《Atmospheric and Oceanic Science Letters》 2011年第6期316-323,共8页
This study investigated the second indirect climatic effect of anthropogenic aerosols,including sulfate,organic carbon(OC) ,and black carbon(BC) ,over East Asia.The seasonal variation of the climatic response to the s... This study investigated the second indirect climatic effect of anthropogenic aerosols,including sulfate,organic carbon(OC) ,and black carbon(BC) ,over East Asia.The seasonal variation of the climatic response to the second indirect effect was also characterized.The simulation period for this study was 2006.Due to a decrease in autoconversion rate from cloud water to rain as a result of aerosols,the cloud liquid water path(LWP) ,and radiative flux(RF) at the top of the atmosphere(TOA) changed dramatically,increasing by 14.3 g m-2 and decreasing by-4.1 W m-2 in terms of domain and annual average.Both LWP and RF changed most in autumn. There were strong decreases in ground temperature in Southwest China,the middle reaches of the Yangtze River in spring and autumn,while maximum cooling of up to-1.5 K occurred in the Chongqing district.The regional and annual mean change in ground temperature reached-0.2 K over eastern China.In all seasons except summer,precipitation generally decreased in most areas north of the Yangtze River,whereas precipitation changed little in South China.Precipitation changed most in summer,with alternating bands of increasing(~40 mm) and decreasing(~40 mm) precipitation appearing in eastern China.Precipitation decreased by 1.5-40 mm over large areas of Northeast China and the Huabei Plain.The domain and annual mean change in precipitation was approximately-0.3 mm over eastern China.The maximum reduction in precipitation occurred in summer,with mean absolute and relative changes of-1.2 mm and-3.8%over eastern China.This study revealed considerable climate responses to the second indirect effect of aerosols over specific regions of China. 展开更多
关键词 AEROSOLS second indirect effect autoconversion liquid water path model simulation
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Aerosol Indirect Effects on Warm Clouds in the Grid-Point Atmospheric Model of IAP LASG(GAMIL) 被引量:7
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作者 Shi Xiang-Jun Wang Bin +3 位作者 Liu Xiao-Hong Wang Ming-Huai Li Li-Juan Dong Li 《Atmospheric and Oceanic Science Letters》 2010年第4期237-241,共5页
Aerosol indirect effects on warm clouds are estimated in the Grid-point Atmospheric Model of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmosphe... Aerosol indirect effects on warm clouds are estimated in the Grid-point Atmospheric Model of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics(IAP LASG)(GAMIL) with a new two-moment cloud microphysics scheme using two different physically-based aerosol activation parameterizations:Abdul-Razzak and Ghan,and Nenes and Seinfeld.The annual global mean changes in shortwave cloud forcing from preindustrial times to present day(a measure of the aerosol indirect effects) estimated from these two parameterizations are remarkably similar:0.76 W m?2 with the Abdul-Razzak and Ghan parameterization,and 0.78 W m?2 with the Nenes and Seinfeld parameterization.Physically-based parameterizations can provide robust representations of aerosol effects on droplet nucleation,meaning that aerosol activation is no longer the most uncertain factor in modeling aerosol indirect effects. 展开更多
关键词 aerosol indirect effect droplet nucleation atmospheric model GAMIL
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Indirect effects among biodiversity loss of mutualistic ecosystems
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作者 Guangwei Wang Xueming Liu +1 位作者 Guanrong Chen Hai-Tao Zhang 《National Science Open》 2022年第2期1-11,共11页
Drastic reduction in biodiversity has been a severe threat to ecosystems,which is exacerbated when losing few species leads to disastrous and even irreparable consequences.Therefore,revealing the mechanism underlying ... Drastic reduction in biodiversity has been a severe threat to ecosystems,which is exacerbated when losing few species leads to disastrous and even irreparable consequences.Therefore,revealing the mechanism underlying biodiversity loss is of uttermost importance.In this study,we show that abundant indirect interactions among mutualistic ecosystems are critical in determining species’status.Combining topological and ecological characteristics,we propose an indicator derived from a dynamic model to identify keystone species and quantify their influence,which outperforms widely-used indicators like degree in realistic and simulated networks.Furthermore,we demonstrate that networks with high modularity,heterogeneity,biodiversity,and less intimate interactions tend to have larger indirect effects,which are more amenable in predicting decline of biodiversity with the proposed indicator.These findings shed some light onto the influence of apposite biodiversities,paving the way from complex network theory to ecosystem protection and restoration. 展开更多
关键词 BIODIVERSITY indirect effect complex network MUTUALISM
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Indirect effects among biodiversity loss of mutualistic ecosystems
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作者 Guangwei Wang Xueming Liu +1 位作者 Guanrong Chen Hai-Tao Zhang 《National Science Open》 2022年第1期8-18,共11页
Drastic reduction in biodiversity has been a severe threat to ecosystems,which is exacerbated when losing few species leads to disastrous and even irreparable consequences.Therefore,revealing the mechanism underlying ... Drastic reduction in biodiversity has been a severe threat to ecosystems,which is exacerbated when losing few species leads to disastrous and even irreparable consequences.Therefore,revealing the mechanism underlying biodiversity loss is of uttermost importance.In this study,we show that abundant indirect interactions among mutualistic ecosystems are critical in determining species’status.Combining topological and ecological characteristics,we propose an indicator derived from a dynamic model to identify keystone species and quantify their influence,which outperforms widely-used indicators like degree in realistic and simulated networks.Furthermore,we demonstrate that networks with high modularity,heterogeneity,biodiversity,and less intimate interactions tend to have larger indirect effects,which are more amenable in predicting decline of biodiversity with the proposed indicator.These findings shed some light onto the influence of apposite biodiversities,paving the way from complex network theory to ecosystem protection and restoration. 展开更多
关键词 BIODIVERSITY indirect effect complex network MUTUALISM
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Indirect Radiative Forcing and Climatic Effect of the Anthropogenic Nitrate Aerosol on Regional Climate of China 被引量:14
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作者 李树 王体健 +1 位作者 庄炳亮 韩永 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第3期543-552,共10页
The regional climate model (RegCM3) and a tropospheric atmosphere chemistry model (TACM) were coupled, thus a regional climate chemistry modeling system (RegCCMS) was constructed, which was applied to investigat... The regional climate model (RegCM3) and a tropospheric atmosphere chemistry model (TACM) were coupled, thus a regional climate chemistry modeling system (RegCCMS) was constructed, which was applied to investigate the spatial distribution of anthropogenic nitrate aerosols, indirect radiative forcing, as well as its climatic effect over China. TACM includes the thermodynamic equilibrium model ISORROPIA and a condensed gas-phase chemistry model. Investigations show that the concentration of nitrate aerosols is relatively high over North and East China with a maximum of 29μg m-3 in January and 8 μg m-3 in July. Due to the influence of air temperature on thermodynamic equilibrium, wet scavenging of precipitation and the monsoon climate, there are obvious seasonal differences in nitrate concentrations. The average indirect radiative forcing at the tropopause due to nitrate aerosols is -1.63 W m 2 in January and -2.65 W m 2 in July, respectively. In some areas, indirect radiative forcing reaches -10 W m-2. Sensitivity tests show that nitrate aerosols make the surface air temperature drop and the precipitation reduce on the national level. The mean changes in surface air temperature and precipitation are 0.13 K and -0.01 mm d-1 in January and -0.09 K and -0.11 mm d-1 in July, respectively, showing significant differences in different regions. 展开更多
关键词 nitrate aerosol indirect radiative forcing indirect climate effect regional climate atmosphericchemistry
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Analytical Studies of the Cloud Droplet Spectral Dispersion Influence on the First Indirect Aerosol Effect 被引量:5
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作者 解小宁 刘晓东 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第5期1313-1319,共7页
Atmospheric aerosols (acting as cloud condensation nuclei) can enhance the cloud droplet number concentration and reduce the cloud droplet size, and in turn affect the cloud optical depth, as well as the cloud albed... Atmospheric aerosols (acting as cloud condensation nuclei) can enhance the cloud droplet number concentration and reduce the cloud droplet size, and in turn affect the cloud optical depth, as well as the cloud albedo, and thereby exert a radiative influence on climate (the first indirect aerosol effect). In this paper, based on various relationships between cloud droplet spectral dispersion (c) and cloud droplet number concentration (Nc), we analytically derive the corresponding expressions of the cloud radiative forcing induced by changes in the cloud droplet number concentration. Further quantitative evaluation indicates that the cloud radiative forcing induced by aerosols for the different ^-Nc relationships varies from -29.1% to 25.2%, compared to the case without considering spectral dispersion (e = 0). Our results suggest that an accurate description of e - Nc relationships helps to reduce the uncertainty of the first indirect aerosol effect and advances our scientific understanding of aerosol-cloud-radiation interactions. 展开更多
关键词 spectral dispersion cloud radiative forcing the first indirect aerosol effect
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An improved recommendation algorithm via weakening indirect linkage effect 被引量:1
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作者 陈光 邱天 沈小泉 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期606-611,共6页
We propose an indirect-link-weakened mass diffusion method(IMD), by considering the indirect linkage and the source object heterogeneity effect in the mass diffusion(MD) recommendation method. Experimental results... We propose an indirect-link-weakened mass diffusion method(IMD), by considering the indirect linkage and the source object heterogeneity effect in the mass diffusion(MD) recommendation method. Experimental results on the MovieLens, Netflix, and RYM datasets show that, the IMD method greatly improves both the recommendation accuracy and diversity, compared with a heterogeneity-weakened MD method(HMD), which only considers the source object heterogeneity. Moreover, the recommendation accuracy of the cold objects is also better elevated in the IMD than the HMD method. It suggests that eliminating the redundancy induced by the indirect linkages could have a prominent effect on the recommendation efficiency in the MD method. 展开更多
关键词 bipartite network mass diffusion recommender system indirect linkage effect
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On the parameters for electrocaloric effect predicted by indirect method
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作者 刘宏波 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期486-488,共3页
The influences of specific heat capacity CP, temperature step ?T, electric field step ?E, and initial electric field E1 on predicted electrocaloric(EC) temperature ?T of monodomain Ba TiO3 are examined by combini... The influences of specific heat capacity CP, temperature step ?T, electric field step ?E, and initial electric field E1 on predicted electrocaloric(EC) temperature ?T of monodomain Ba TiO3 are examined by combining the Maxwell equation and phenomenological theory. Since the procedure is similar to indirect measurement of the EC effect, the results can serve as a reference for experiments. The results suggest that(i) it is reasonable to use zero-field CP,(ii) optimized ?T should be 2 K,(iii) it is better to keep △E 〈 EC, and(iv) E1〈 EC. Here, EC is the coercive field of material. 展开更多
关键词 electrocaloric effect indirect method BaTiO3
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梯级水电开发的局地气候影响及累积生态效应研究进展
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作者 汪东川 刘云绮 +3 位作者 赵爽 俞长锦 曾孔鹏 张万恒 《生态环境学报》 北大核心 2025年第3期484-498,共15页
梯级水电开发是指在同一河流或流域内呈阶梯状修建一系列水利工程,以系统地利用水资源的开发方式,实现水资源的充分利用和有序调配。为了满足梯级水电开发生态保护和功能修复的需求,需要深入研究梯级水库群对局地气候、生态效应的集群... 梯级水电开发是指在同一河流或流域内呈阶梯状修建一系列水利工程,以系统地利用水资源的开发方式,实现水资源的充分利用和有序调配。为了满足梯级水电开发生态保护和功能修复的需求,需要深入研究梯级水库群对局地气候、生态效应的集群累积效应及其时空分异规律。该文梳理了近年来水电开发局地气候影响与生态效应及梯级水电开发累积效应的前沿进展,并针对金沙江干热河谷这一生态脆弱区水电开发的局地气候影响和生态效应进行了深入探讨。结果表明,水电开发对局地气候湿度、温度、降雨等气候因素产生有季节差异的显著影响。生态效应方面,水生生态表现为水文条件的改变和对水生生物生命活动的影响;陆生生态表现为水电开发不仅直接干扰动植物栖息地影响陆生生态,还通过改变河流水文特征、土壤、局地气候等因素,对陆生生态产生间接影响。此外,相比于单一水电站,梯级水电开发对整个流域局地气候和生态的累积效应尤为显著,呈现出系统叠加性、阻断差异性、潜在滞后性和要素选择性。金沙江干热河谷水库尺度上的气候变化是全球气候变化和水库局地气候影响共同作用下产生的综合性变化,并对陆生生态产生了间接影响,促进了库区植被的恢复和更新。通过融合多学科技术的形式对典型水电开发区域的局地气候、生态效应展开研究,剔除水库气候效应中的全球气候变化影响,分析陆生生态对气候变化的响应机制,探明两者的时空分异规律及累积效应,以期破解梯级水电开发生态环境保护难题,有助于统筹推进“碳达峰、碳中和”中提出的“生态优先”这一重要原则。 展开更多
关键词 梯级水电 局地气候 生态效应 间接影响 流域累积 金沙江干热河谷
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The ethics of theft:Reevaluating the impacts of floral larceny on plant reproductive success
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作者 Jin-Ru Zhong Xiao-Fang Jin +6 位作者 Michael C.Orr Xiao-Qing Li Yong-Deng He Sheng-Wei Wang Qing-Feng Wang Chun-Feng Yang Zhong-Ming Ye 《Plant Diversity》 2025年第1期148-158,共11页
Plants and their interaction partners offer unparalleled views of evolutionary ecology.Nectar larceny,entailing nectar extraction without pollinating,is thought to be an example of a harmful,antagonistic behavior,but ... Plants and their interaction partners offer unparalleled views of evolutionary ecology.Nectar larceny,entailing nectar extraction without pollinating,is thought to be an example of a harmful,antagonistic behavior,but the precise consequences of floral larceny on plant reproductive success remain contentious.We conducted a comprehensive meta-analysis of 153 studies across 120 plant species,using 14 moderators to assess the effects of floral larceny on plant reproductive success and examine the key moderators.We found that floral larceny negatively impacts flower traits,pollinator visitation,pollen deposition,and fruit set,while having a neutral effect on critical female fitness indicators,such as seed set and seed quality,as well as on male fitness.By altering pollinator behavior,floral larceny may reduce geitonogamy,potentially enhancing genetic diversity.Additionally,factors such as pollinator type,plant mating system,and pollen limitation were identified as key moderators of these effects.Our analysis reveals an ultimately neutral effect of floral larceny on plant reproductive success,with potential benefits in certain contexts.These findings suggest that floral larceny plays a complex and multifaceted role within plant-pollinator interactions,facilitating the evolutionary stability and coexistence of floral larcenists and host plants. 展开更多
关键词 Floral larceny Nectar robbing Nectar thief Plant-pollinator interactions Plant reproductive success indirect effects
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基于间接预应力的复杂曲面大跨度混凝土空间结构设计
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作者 苏朝阳 石硕 +1 位作者 贾水钟 李亚明 《建筑施工》 2025年第10期1543-1547,1557,共6页
复杂曲面混凝土空间结构中壳体由于受力大,采用一般的增大壳体厚度等方法已无法满足规范要求,因此提出基于间接预应力的复杂曲面大跨度混凝土空间结构设计。考虑预应力的效应、预应力大小、环梁的设置、环梁的尺寸,以及环梁的属性,采用... 复杂曲面混凝土空间结构中壳体由于受力大,采用一般的增大壳体厚度等方法已无法满足规范要求,因此提出基于间接预应力的复杂曲面大跨度混凝土空间结构设计。考虑预应力的效应、预应力大小、环梁的设置、环梁的尺寸,以及环梁的属性,采用有限元分析对结构性能进行分析。结果表明,施加预应力等措施后壳体应力的应力大为减小,预应力起到的作用非常明显;环梁中增设预应力筋后,无论是壳体的应力还是结构的位移都得到了大幅度的改善;增加环梁预应力,对结构更加有利;间接预应力构件的截面尺寸变化,对壳体的应力和变形影响的幅度不超过10%;环梁位置的改变对悬挑区域的应力分布产生了较大影响,导致这些区域的抗裂性能下降。总的来说,间接预应力的设置对结构起到了良好的空间效应,不仅能有效降低板壳的应力,提高结构的承载能力,还能为悬挑梁提供支撑,改善悬挑梁的受力性能。 展开更多
关键词 间接预应力 空间效应 复杂曲面大跨度混凝土空间结构 有限元分析 环梁
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论纪检监察机关参与民营企业廉洁合规治理的路径:基于限度和效力的考量
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作者 李蓉 侯天豪 《成都理工大学学报(社会科学版)》 2025年第4期56-68,共13页
民营企业廉洁合规作为新兴的预防性合规模式,是“治未病”的生动体现,其旨在通过内部治理、风险防控,主动消除腐败风险。然而,民企廉洁合规面临内生动力不足及外部督导缺乏等现实困境。纪检监察机关借助政策导向、法律指引及自身独特优... 民营企业廉洁合规作为新兴的预防性合规模式,是“治未病”的生动体现,其旨在通过内部治理、风险防控,主动消除腐败风险。然而,民企廉洁合规面临内生动力不足及外部督导缺乏等现实困境。纪检监察机关借助政策导向、法律指引及自身独特优势,可以有效助推该合规机制的建设。在纪监协同、“间接介入”的限度下,纪检监察机关通过“法律督导—信息互通—文化激励”的三维治理进路,实施穿透式监督、廉洁信息大数据共享、分类分级介入以及廉洁文化建设等措施,可以充分发挥其作为党内监督机关及国家监察专责机关的独特效力,在维护市场活力与防控腐败风险之间实现动态平衡,为民营企业廉洁合规建设提供理论支撑和实践路径。 展开更多
关键词 民营企业 廉洁合规 纪检监察 间接介入 限度和效力
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隔物灸联合小儿推拿治疗消化不良性腹泻的疗效观察
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作者 王伟平 杨明娟 +2 位作者 刘蕾 夏爱燕 徐惠卿 《中国现代药物应用》 2025年第14期14-17,共4页
目的观察隔物灸联合小儿推拿治疗消化不良性腹泻的疗效。方法选取200例消化不良性腹泻患儿,按照1∶1随机数字法分为观察组和对照组,每组100例。对照组接受常规西医治疗,观察组在对照组基础上接受隔物灸联合小儿推拿治疗。比较两组患儿... 目的观察隔物灸联合小儿推拿治疗消化不良性腹泻的疗效。方法选取200例消化不良性腹泻患儿,按照1∶1随机数字法分为观察组和对照组,每组100例。对照组接受常规西医治疗,观察组在对照组基础上接受隔物灸联合小儿推拿治疗。比较两组患儿的临床疗效、症状缓解时间、症状积分、不良反应发生情况及家属满意度评分。结果观察组总有效率为93.00%,高于对照组的76.00%(P<0.05)。观察组腹胀腹痛、腹泻、大便性状缓解时间分别为(1.24±0.41)、(2.09±0.54)、(2.16±0.48)d,均短于对照组的(2.16±0.53)、(3.15±0.87)、(2.71±0.56)d(P<0.05)。治疗后,两组患儿腹部胀满、腹部胀痛、易饱纳差积分均有下降,且观察组均低于对照组(P<0.05)。观察组不良反应发生率为4.00%,与对照组的8.00%比较无统计学差异(P>0.05)。观察组家属满意度评分为(6.14±1.03)分,高于对照组的(5.61±1.21)分(P<0.05)。结论隔物灸联合小儿推拿可有效提高消化不良性腹泻患儿的临床疗效,缩短临床症状缓解时间,降低症状积分,且具安全性。 展开更多
关键词 隔物灸 小儿推拿 消化不良性腹泻 疗效评价
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酶替代疗法在中国法布雷病患者肾脏并发症中的成本效用分析 被引量:1
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作者 陈登云 郑斌 刘茂柏 《中国医院药学杂志》 北大核心 2025年第5期503-509,共7页
目的:比较中国人群中酶替代疗法(enzyme replacement therapy,ERT)与常规对症治疗在法布雷病患者肾脏并发症中的经济性。方法:从中国医疗卫生体系角度,基于中国人群回顾性队列研究的个体患者数据,采用匹配调整间接比较法调整患者基线特... 目的:比较中国人群中酶替代疗法(enzyme replacement therapy,ERT)与常规对症治疗在法布雷病患者肾脏并发症中的经济性。方法:从中国医疗卫生体系角度,基于中国人群回顾性队列研究的个体患者数据,采用匹配调整间接比较法调整患者基线特征,间接比较两种方案的临床疗效。通过构建Markov模型,模拟10年内法布雷病患者的肾病健康状况变化,转移概率数据基于中国人群的个体随访数据,效用值数据来源于文献,成本数据参考相关文献和中国某省省属公立医疗机构收费标准,主要的结果指标是终末期肾损伤,以2023年3倍国内生产总值作为意愿支付(willingness to pay,WTP)阈值进行成本效用分析,同时进行单因素敏感性分析、概率敏感性分析和情境分析来验证结果的稳健性。结果:相比常规对症治疗,ERT组患者获得的质量调整生命年(quality-adjusted life-years,QALYs)为0.7,增量成本为2311405.4元,增量成本效用比为3314875.70元/QALY,显著高于WTP阈值(268074元/QALY)。当阿加糖酶α的药品价格下降至37891.266元时,得到ICER≤WTP,则认为ERT具有经济性。单因素敏感性分析、概率敏感性分析和情境分析验证了结果的稳健性。结论:该研究强调了优化ERT治疗策略和降低治疗成本的重要性,并为医保决策提供参考依据,以制定更合理的医疗保障政策。 展开更多
关键词 法布雷病 酶替代疗法 匹配调整间接比较 成本效用分析
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农村电商持续赋能间接参与农户的增收机制 被引量:2
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作者 关昕 胡志全 《中国流通经济》 北大核心 2025年第8期50-61,共12页
共同富裕是社会主义的本质要求,是中国式现代化的重要特征。作为数字经济的重要载体,农村电商对促进农户增收、实现共同富裕具有重要意义。基于间接参与电商视角,利用陕西、贵州、江苏、山东、河北、安徽6省609个农户的微观调研数据,采... 共同富裕是社会主义的本质要求,是中国式现代化的重要特征。作为数字经济的重要载体,农村电商对促进农户增收、实现共同富裕具有重要意义。基于间接参与电商视角,利用陕西、贵州、江苏、山东、河北、安徽6省609个农户的微观调研数据,采用基准回归、中介效应两步法,检验农村电商对未通过电商销售产品的农户是否具有溢出效应,探究农村电商助推间接参与电商农户的增收机制。研究结果显示,农村电商对间接参与农户仍有显著的溢出效应。具体而言,不具备电商销售技能的农户可通过与农村电商经营主体缔结合作关系的方式间接参与电商,进而享受数字红利。机制分析表明,农村电商通过规模化经营,推动土地资源整合、促进非农就业与降低滞销风险三种方式,提升间接参与电商的农户家庭收入。按区域看,间接参与电商的增收效应具有显著的区域差异,在河北省、山东省等传统农区尤为显著,对河北省农户的增收效应最强,对江苏省和陕西省农户没有直接影响。按收入类型看,间接参与电商对不同类型的收入均具有显著正向影响,其中对工资性收入提升效果最明显,对农业经营性收入的提升效果最弱。鉴于此,为推动农村电商发展与农户增收,需强化政策扶持,完善辐射带动机制,推动农产品标准化品牌化;完善农业规模化经营制度,保障土地流转,提升电商服务能力;实施区域适配政策,优化农产品利润分配;激活财产性收入提升潜力,提高非农就业能力,优化多元收入增长机制;通过技能培训、资金扶持与示范引领,建立农户电商转型赋能机制,助力间接参与农户转型。 展开更多
关键词 农村电商 间接参与 溢出效应 增收机制
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基于FEM-IBIEM的河谷坝址地震动输入方法及地震动场模拟研究
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作者 王飞 刘云贺 +3 位作者 李虎 薛炳 牟猷 宋志强 《振动与冲击》 北大核心 2025年第6期244-253,共10页
地震动输入是大坝抗震安全分析的基础,然而目前地震动输入尚未合理考虑河谷散射效应对大坝动力响应的影响。将河谷场地总运动场分解为平坦半空间自由场和河谷散射场分别求解,采用间接边界积分方程法求解河谷场地散射场,将其与平坦半空... 地震动输入是大坝抗震安全分析的基础,然而目前地震动输入尚未合理考虑河谷散射效应对大坝动力响应的影响。将河谷场地总运动场分解为平坦半空间自由场和河谷散射场分别求解,采用间接边界积分方程法求解河谷场地散射场,将其与平坦半空间自由场叠加获得河谷场地总运动场(地震动场),通过封闭解验证了间接边界积分方程法的精度。进而,采用有限元法模拟河谷场地内部,同时将河谷地基截断边界处总运动场转换为等效地震输入荷载,建立了总运动场结合黏弹性人工边界的波动输入方法。应用基于有限元法-间接边界积分方程法建立地震波动输入方法,数值求解了梯形河谷场地地震动场,分析了自由场波动输入和总运动场波动输入下河谷动力响应的差异。结果表明:自由场波动输入下河谷关键位置位移峰值、波形与精确解存在较大偏差,水平和竖向位移最大误差分别达15.6%、29.3%;总运动场波动输入下位移峰值、波形与精确解拟合良好。该研究建立的波动输入方法计算精度高,合理考虑了河谷散射效应,为更准确地预测河谷上大坝动力响应提供了基础。 展开更多
关键词 河谷 散射效应 间接边界积分方程法 地震动输入 总运动场
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基于效应量法的车桥耦合简支桥梁损伤识别研究
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作者 郭毅航 王江飞 +5 位作者 伍妍妮 梁春雨 徐建国 黄亮 周奇 寇磊 《世界地震工程》 北大核心 2025年第3期1-15,共15页
目前广泛采用的直接检测法存在传感器布置繁琐、人力物力投资大、需要封闭交通等弊端,亟需研究新型的桥梁健康检测方法以提升检测效率。提出了一种新型的桥梁损伤识别方法,该方法基于Cohen’s d效应量指标,通过车桥耦合振动分析,在关键... 目前广泛采用的直接检测法存在传感器布置繁琐、人力物力投资大、需要封闭交通等弊端,亟需研究新型的桥梁健康检测方法以提升检测效率。提出了一种新型的桥梁损伤识别方法,该方法基于Cohen’s d效应量指标,通过车桥耦合振动分析,在关键位置布置少量加速度传感器,并结合信号处理技术增强噪声滤除效果,实现了对桥梁损伤的准确识别。此外,还引入了边界细分法,以提高对边界损伤的识别精度。为验证所提方法的有效性,构建了不同损伤状态(包括无损、跨中损伤、1/4跨及3/4跨损伤)的桥梁数值模型,验证了效应量作为损伤指标的有效性与准确性。通过进行基于间接测量技术的实桥试验,利用东华DH5907G无线传感器进行模态测试和数据采集,通过样条插值法对数据进行预处理,成功提取了桥梁的自振频率,降低成本的同时提高了数据的准确性,并分析了随机车流对桥梁损伤识别结果的影响。结果表明:简支梁桥的振动因受到随机车流的影响而加强,有助于提高损伤识别的准确性。提出的方法为桥梁健康监测提供了一种新的量化工具,能够在不干扰交通的情况下,快速准确地识别桥梁损伤,对桥梁维护和安全评估有重要的实际应用价值。 展开更多
关键词 车桥耦合系统 间接检测 损伤识别 效应量法 桥梁模态振型
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农村电商对农民增收的作用机制分析
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作者 薛茗豪 王志强 《智慧农业导刊》 2025年第21期5-8,共4页
农村电商作为数字经济与乡村振兴战略深度融合的产物,能够有效调度市场、技术、组织和人力等资源,重构传统的农业生产关系。农村电商对农民增收还形成明显的长尾效应,电商平台突破地域限制,能够精准对接农村供应与市场需求,借助数字化... 农村电商作为数字经济与乡村振兴战略深度融合的产物,能够有效调度市场、技术、组织和人力等资源,重构传统的农业生产关系。农村电商对农民增收还形成明显的长尾效应,电商平台突破地域限制,能够精准对接农村供应与市场需求,借助数字化的工具,进一步降低农产品对外交易的成本。电商发展所带来的现代分配关系及人力资源管理方式,还能够为农村的发展提供持续动能。为进一步发挥农村电商对农民增收的作用,各地政府应加强冷链物流建设,完善5G移动网络。为农民提供电商发展的相关培训,形成政策创新协同体系,促进农民增收与农业现代化发展,形成良性循环。 展开更多
关键词 农村电商 农民增收 新农人 直接效应 间接效应
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