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货币政策传导渠道、宏观经济增长与企业投资效率

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当代财经 2015年第8期 108-119页

作者：张超刘星田梦可重庆大学经济与工商管理学院重庆400033

以我国A股上市公司为样本,研究了在不同的宏观经济增长环境下,两类货币政策传导渠道对企业投资效率的影响。研究发现,在经济增长平稳时期,货币供给与企业投资不足以及过度投资正相关,信贷供给与投资不足负相关、与过度投资正相关;在经... 详细信息

以我国A股上市公司为样本,研究了在不同的宏观经济增长环境下,两类货币政策传导渠道对企业投资效率的影响。研究发现,在经济增长平稳时期,货币供给与企业投资不足以及过度投资正相关,信贷供给与投资不足负相关、与过度投资正相关;在经济增长非平稳时期的信贷渠道作用发生部分反转;在经济增长乏力时期的宽松货币供给提高了企业投资效率。研究还发现,利率是货币渠道的有效替代变量,上述影响在不同产权性质特征和行业特征下具有强度差异。在进一步的研究中,我们发现企业在经济增长乏力时期存在显著的"蛰伏"效应和择机调整行为。

关键词：货币政策货币渠道信贷渠道宏观经济增长企业投资效率

Characteristics and Influencing Factors of PM2.5-O3 Composite Pollution in Henan Province

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Huanjing kexue/Environmental Science 2025年第3期46卷 1285-1301页

作者： Wang, meng-ke Cao, Le Xu, Li-Qiang Wang, Yu-Xi Kong, Hai-Jiang Gao, meng-meng Qin, Yang meng, Kai Zhao, tian-Liang School of Atmospheric Physics Nanjing University of Information Science and Technology Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing210044 China Henan Meteorological Observatory Zhengzhou450003 China Hebi Meteorological Bureau Hebi458000 China Hebei Meteorological Science Research Institute Shijiazhuang050021 China key Laboratory of Meteorology and Ecological Environment in Hebei Province Shijiazhuang050021 China

The PM2.5-O3 composite pollution in Henan Province has notable impacts on the economy,society,and daily life of the region,exhibiting a more complex nature than single pollution. Therefore,this study utilized air quality data,ground - based meteorological data,boundary layer height,CO concentration,emission inventory,and other information from 17 cities in Henan Province to investigate the spatial-temporal distribution,formation causes,and influencing factors of PM2.5-O3 composite pollution from May 2014 to December 2023. The PSCF and CWT methods were used to identify possible source areas of composite pollution. The results showed that:① Due to the government's control of PM2.5 pollution and the impact of the epidemic,the PM2.5-O3composite pollution events in Henan Province from 2014 to 2023 showed an overall downward trend,however,rebounded during the resumption of work and production after the epidemic in 2022. Before 2018,O3 concentration was the major factor determining the occurrence of composite pollution due to severe PM2.5 pollution. After 2018,the decrease in PM2.5 concentration increased its importance,especially the decrease in PM2.5 concentration from May to September in Henan Province,which was the primary reason for the reduction in composite pollution frequency in recent years. ② The monthly distribution of composite pollution showed a bimodal pattern,with peaks in April and October,corresponding to two periods when O3 increased while PM2.5 decreased and O3 decreased while PM2.5 increased,respectively,whereas the rainy season in July and August had a mitigating effect on composite pollution. ③ The severity of composite pollution in Henan Province was in the order of north > central > south and the topography also had a certain impact on the severity of composite pollution. ④ The meteorological conditions during the occurrence of composite pollution were moderate temperature,specific humidity,and CO concentration between PM2.5 pollution and O3 polluti

关键词： Wind

Obesity paradox in patients with community-acquired pneumonia:Have you fully considered the confounding factors?

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World Journal of Clinical Cases 2025年第9期13卷 53-55页

作者： Jin-ke Sun Hui tian Department of Pulmonary and Critical Care Medicine Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan 250000Shandong ProvinceChina Department of Critical Care Medicine Liaocheng People’s HospitalLiaocheng 252000Shandong ProvinceChina

There exists a notion that there is an obesity paradox in the prognosis of community-acquired *** other words,obese individuals with communityacquired pneumonia have a better *** study by Wang et al supports this claim,but we believe that the obesity paradox should not be proposed hastily as it is influenced by numerous subjective and objective confounding factors.

关键词： Community-acquired pneumonia Mortality Body mass index Overweight Obesity paradox

含铀废水中[UO_(2)(OH)_(m)(H_(2)O)_(n)]^(2-m)形态的模拟计算

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核化学与放射化学 2024年第6期46卷 594-604,I0004页

作者：曾秀琳田孟克唐双凌居学海淮南师范学院化学与材料工程学院安徽淮南232038 南京理工大学化学与化工学院环境与生物工程学院江苏南京210094

乏燃料含铀废水既是放射性污染物,也是可回收利用的铀资源。U(Ⅵ)在水溶液中的化学形态对其在环境中的迁移性和溶液的形态转化调控有重要意义。采用密度泛函理论方法计算研究铀酰离子与羟基和水形成配合物的结构和性质,求得优化几何构... 详细信息

乏燃料含铀废水既是放射性污染物,也是可回收利用的铀资源。U(Ⅵ)在水溶液中的化学形态对其在环境中的迁移性和溶液的形态转化调控有重要意义。采用密度泛函理论方法计算研究铀酰离子与羟基和水形成配合物的结构和性质,求得优化几何构型、能量、形成过程和热力学性质。自发生成的6配位配合物中,羟基和水的配位数分别是4和2。直线型铀酰阳离子同羟基和水形成配合物,按Oyl-U-Oyl(Oyl表示酰基氧)角度不同,存在线型和“V”型两种构型。分子式相同时,铀酰基团的U-Oyl,键长随着Oyl-U-Oyl角度的减小而增长。随着OH^(-)和H_(2)O配体数增加,配合物的结构趋于笼状;当OH^(-)配体数为3或4时,倾向于生成“V”型铀酰配合物。逐级生成[UO_(2)(OH)_(m)]^(2-m)配合物时,开始释放出大量的能量,但是随着OH配位数增加,释放的能量急剧减少,直至吸收能量。而逐级生成[UO_(2)(H_(2)O)_(n)]^(2+)配合物时,则持续释放出少量能量;H2O配体数增加时有利于形成稳定配合物。生成[UO_(2)(OH)_(m)]^(2-m)(m<4)配合物的反应能自发进行;而生成[UO_(2)(OH)_(4)]^(2-)配合物的反应,仅线型[UO_(2)(OH)_(3)]^(-)生成“V”型[UO_(2)(OH)_(4)]^(2-)是自发过程。

关键词：乏燃料铀处理铀酰离子密度泛函理论热力学性质

The upper tropospheric-lower stratospheric ozone drives summer precipitation and wildfire changes in West Siberia

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Science Bulletin 2025年第2期70卷 255-262页

作者： Fei Xie Yan Xia Wenshou tian Martyn P.Chipperfield Wuhu Feng ke Gui Yingli Niu Na Liu Yuanyuan Han School of Systems Science Beijing Normal UniversityBeijing 100875China key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China School of Earth and Environment University of LeedsLeedsLS29JTUK National Centre for Earth Observation University of LeedsLeedsLS29JTUK National Centre for Atmospheric Science University of LeedsLeedsLS29PHUK State key Laboratory of Severe Weather&key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China key Laboratory of Textile Chemical Engineering Auxiliaries School of Environmental and Chemical EngineeringXi’an Polytechnic UniversityXi’an 710048China

Siberian wildfires are pivotal in determining the carbon cycle and climate dynamics,exerting a profound impact on the ecosystems of the entire Arctic *** the past few decades,variations in summer precipitation in West Siberia have significantly influenced wildfire *** study analyzed precipitation trends in West Siberia from 1982 to 2021 using observations and transient simulations,uncovering a strong correlation between precipitation variability and ozone concentrations in the upper troposphere-lower stratosphere(UTLS).Heightened UTLS ozone levels warm the upper atmosphere over West Siberia during *** warming modifies the regional polar jet stream,intensifying its southern branch and weakening the northern one,leading to a southward shift in the jet ***,cyclonic circulation anomalies emerge in the upper troposphere,characterized by a barotropic structure with unusual upward movements around 60°*** upward motion triggers corresponding anomalies in zonal winds in the lower troposphere,fostering a low-pressure system at the *** atmospheric shift results in an influx of warm,moist air from the south and cold,dry air from the north into Siberia,enhancing cloud formation and ***,our analysis suggests that the rise in summer precipitation in West Siberia between 1993 and 2010 is linked to increased UTLS ozone concentrations during this ***,the decline in UTLS ozone since 2010 may increase the risk of wildfires by suppressing *** findings underscore the pivotal role of stratospheric chemistry in shaping the regional climate and wildfire behavior.?2024 Science China *** by Elsevier *** Science China *** rights are reserved,including those for text and data mining,AI training,and similar technologies.

关键词： Upper troposphere-lower stratosphere Ozone Radiative effect Precipitation Siberia

Assessing the ecological effects of the World's Largest Forestry Eco-engineering: Three-North Protective Forest Program within the initially scheduled range from 1978 to 2022

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Science China(Life Sciences) 2025年第2期68卷 314-327页

作者： Xiao Zheng Jiaojun Zhu G.Geoff Wang Qiaoling Yan Tao Sun Lining Song tian Gao Yirong Sun Xiufen Li Kai Yang Jinxin Zhang Lizhong Yu ke Qi Lanlin Zhao Deliang Lu Zhanyuan Lu CAS key Laboratory of Forest Ecology and Silviculture Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Qingyuan Forest CERN National Observation and Research StationShenyang 110016China Department of Forestry and Environmental Conservation Clemson UniversityClemson 29634USA Agronomy College Shenyang Agricultural UniversityShenyang 110866China University of Chinese Academy of Sciences Beijing 100049China Inner Mongolia Academy of Agricultural&Animal Husbandry Sciences Hohhot 010031China

China's Three-North Protective Forest Program(TNP) is the world's most ambitious afforestation project(ongoing from 1978 to 2050), which aims to increase forest coverage through afforestation and reforestation, protect agriculture, reduce soil erosion, and control desertification. Although TNP has been ongoing for 45 years, its rationales and effects remain uncertain. Here, we conducted a rangewide assessment of TNP by analyzing data from >10,000 scenes of satellite images and >50,000 field survey plots. The TNP range and definitions of shelterbelts, arboreal forests, and shrublands were changed during the study period, but we used the initial TNP range(4.07 million km2) and the definitions in 1978 for keeping the consistency, comparability, and comprehensiveness. The TNP increased forest coverage from 5.05% in 1978 to 9.69% in 2022, with arboreal forests, shrublands, and shelterbelts increasing by 42.5%, 184.4%,and 53.6%, respectively. However, only 40.1% of the 471,113 km2afforested area was established between 1978 and 2022. The wellestablished shelterbelts improved crop yield by 4.3%-9.5%, but only 10.2% of all the farmlands in TNP regions(TNR) were protected. The total area of soil erosion due to hydraulic forces was reduced by 447,363 km2, with 61% of this reduction attributed to TNP. TNP contributed to the reduction of desertification by 15%, largely due to the low rate of afforestation success and the largely decreased grasslands. The total carbon sequestration from TNP was 1.96 Pg C. Moreover, water storage in TNR showed a decreasing trend, but the contribution rate of TNP was only 7.8%. Our results illustrate that forestry eco-engineering projects are feasible in the management and restoration of arid and semi-arid degraded lands, but attention must be paid to fully considering the ecological carrying capacity of water resources, matching the species to sites, strengthening the post-afforestation management, as well as keeping the balances between composit

关键词： Three-North Program northern China protective forest ecological impacts 45 years

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Anti-programmed death-1 immunotherapy-promising treatment for metastatic colorectal cancer:A case report

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World Journal of Gastrointestinal Oncology 2025年第2期17卷 291-298页

作者： tian-Hao Guo Sheng-Wei Hong Wen-Jian Zhu Yi-Fan Hui Wen-Li Qiu Yan Wu Xuan Li Fei ke Liu Li Hai-Bo Cheng Institute of Health and Regimen Jiangsu Open UniversityNanjing 210036Jiangsu ProvinceChina The First Clinical Medical College Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Radiology Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Oncology Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Pathology Jiangsu Provincial Hospital of Traditional Chinese Medicine(Affiliated Hospital of Nanjing University of Chinese Medicine)Nanjing 210029Jiangsu ProvinceChina

BACKGROUND Colorectal cancer(CRC)is the third most prevalent form of cancer *** patients with CRC,colorectal liver metastasis(CRLM)is the foremost direct contributor to *** recent years,immunotherapy has swiftly risen to prominence as a vital approach for treating a range of solid tumors,including *** present a unique case of a patient suffering from CRLM,with the goal of offering an insightful example and relevant references for the treatment of *** SUMMARY We report a patient who experienced liver metastasis after undergoing successful surgical removal of CRC,with the postoperative pathological stage identified as *** patient has been receiving a combination treatment of Western and Traditional Chinese *** assessments of the patient’s condition have been conducted,encompassing evaluations of serum carcinoembryonic antigen levels,carbohydrate antigen 199,and observations of the tongue complexion and its *** patient achieved clinical remission after anti-programmed death-1 immunotherapy when various systemic therapies *** the diagnosis of CRLM,the patient has survived for more than 6 years,surpassing the expected survival time for those with advanced *** This case illustrates the considerable promise of anti-programmed death-1 immunotherapy in managing CRLM,especially in scenarios of drug resistance and disease progression.

关键词： Colorectal cancer Colorectal liver metastasis Drug resistance Immunotherapy Anti-programmed death-1 Case report

基于蒙特卡洛法的卸胎机械手重复定位精度分析

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机电工程 2017年第10期34卷 1112-1116页

作者：刘瑞仝西萌田仲可青岛科技大学机电工程学院山东青岛266061

针对卸胎机械手的重复定位精度问题,对卸胎机械手进行了在3个铰接部位联合作用下的参数化仿真分析研究,同时对卸胎机械手在有无铰间隙两种条件下对位置、速度、加速度3个方面作了比较。运用Pro/E三维建模建立卸胎机械手的实体模型,通过M... 详细信息

针对卸胎机械手的重复定位精度问题,对卸胎机械手进行了在3个铰接部位联合作用下的参数化仿真分析研究,同时对卸胎机械手在有无铰间隙两种条件下对位置、速度、加速度3个方面作了比较。运用Pro/E三维建模建立卸胎机械手的实体模型,通过Matlab编程得到了卸胎机械手铰间隙的1 000组服从正态分布的随机抽样数据,再将实体模型与得到的参数化数据导入到ADAMS中进行了动力学仿真分析,获得了卸胎机械手在运动过程中的运动变化曲线及位置变化数据。基于蒙特卡洛方法通过计算概率得出了铰间隙大小对卸胎机械手定位精度影响的可靠度。研究结果表明:存在铰间隙的情况下,卸胎机械手在位置、速度和加速度3个方面都有一定的变化,且当许用偏差值-0.25 mm<μ<0.25 mm时,卸胎机械手的定位精度可靠性是可以得到保证的。

关键词：机械手铰间隙蒙特卡洛法 ADAMS 精度

Estimation of Vegetation Carbon Source/sink and Its Response to Land Use Change in the Loess Plateau，A Case Study of Yanhe River Basin

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Huanjing kexue/Environmental Science 2025年第3期46卷 1657-1665页

作者： Guan, Ya-Bing Wang, Jun Tan, Li Yang, Sheng-tian Zhao, Wen-Wu Chen, ke Zhang, Xi-Tong Ministry of Natural Resources Beijing100035 China key Laboratory of Land Consolidation and Rehabilitation Ministry of Natural Resources Beijing100035 China College of Water Science Beijing Normal University Beijing100875 China Institute of Land Surface System and Sustainable Development Faculty of Geographical Science Beijing Normal University Beijing100875 China College of Geography and Tourism Huanggang Normal University Huanggang438000 China

The transformation of ecosystem types caused by land use change plays an extremely important role in the regional carbon cycle. Studying the response of vegetation carbon source/sink systems to land use change is helpful to improve the understanding of the vegetation carbon sink effect in the process of land use change. However,few studies have focused on the response of vegetation carbon sources/sinks to land use change. The CASA model and soil microbial respiration model were combined to estimate the net ecosystem productivity(NEP)of vegetation in the Yanhe River Basin in the Chinese Loess Plateau from 2000 to 2020 based on remote sensing,meteorological,and land use data. The spatiotemporal pattern evolution characteristics of the carbon source/sink and land use were identified using a significance test,univariate linear regression analysis,and land use status transition matrix methods,and the response of the carbon source/sink to land use change was further analyzed. The results showed that from 2000 to 2020,the multi-year average NEP in the Yanhe River Basin showed a spatial distribution pattern of lower in the upstream and higher in the midstream and downstream. The Yanhe River Basin belonged to a weak carbon sink area as a whole,with this type of area accounting for 88.81% of the basin area. The annual NEP of the basin showed a significant increase trend in fluctuations,and the carbon sequestration capacity was gradually improving. The areas with significant and extremely significant increases in annual NEP accounted for 65.78% of the basin area,and the types of annual NEP restoration,basic stability,and degradation accounted for 79.70%,10.15%,and 10.15% of the basin area,respectively. Over the past 20 years,the land use transformation of Yanhe River Basin mainly included five types,that is,cropland was converted into grassland,woodland,and construction land,and grassland was converted into cropland and woodland. The land use in the Yanhe River Basin was mainl

关键词： Regression analysis