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Regional Factors in Yemen’s Integration Reunification
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作者 XIA Lu 《Asian Journal of Middle Eastern and Islamic Studies》 2010年第4期102-120,I0006,共20页
Among the divided nations after the Second World War,Yemen was the only country which was reunified by integration model.The author believes that this process could be explained not only by the nation's power at t... Among the divided nations after the Second World War,Yemen was the only country which was reunified by integration model.The author believes that this process could be explained not only by the nation's power at the national level and by the international system at the global level,but also in the logic of regional factors at the regional level.This article attempts to analyses two aspects of regional factors in Yemen’s integration reunification.The first one is"hard regional factor"such as Regional Big Power.The Kingdom of Saudi Arabia is the regional big power in this issue.The Second one is"soft regional factor"like Regional Multilateral Organization.In the case of Yemen’s reunification,the League of Arab States(LAS)is the soft regional factor.After analysis,we can draw a conclusion:"Regional factors affect the divided nation's reunification model".(1)As to the hard regional factor,if both of the divided separates had normal diplomatic relationships with regional big power,it would be conducive to nation’s integration reunification.(2)As to the soft regional factor,if both of the divided separates co-operated in a mature regional multilateral organization in Lockean Culture,it would contribute to the integration reunification model.This research will count for China’s reunification studies to some extent. 展开更多
关键词 Divided Nation Integration Reunification Kingdom of Saudi Arabia League of Arab States regional factors Yemen
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Impact of Regional Economy on Internal Migration in Yangtze Delta:Based on Panel Data
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作者 Zhang Yina Ren Yuan 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第4期49-56,共8页
Metropolitan Shanghai, in Yangtze River Delta (YRD), plays undoubtedly the leading role in the economic development in China, and becomes one of the most important population con- gregation areas. It is also widely re... Metropolitan Shanghai, in Yangtze River Delta (YRD), plays undoubtedly the leading role in the economic development in China, and becomes one of the most important population con- gregation areas. It is also widely regarded as the sixth uprising urban agglomeration in the world. Based on the quantitative stud- ies on basic socioeconomic and demographic profile on the num- ber and transition of population, this paper concluded that the migration is the key factor for population dynamics in YRD. Then, what are the regional economic factors affecting the migration of different cities in YRD? The panel data show that the different wage level is the most important factor that affects the immigra- tion in YRD. Moreover, the ratio of industry sector and service sector has an impact on attracting immigration. However, per-capital GDP and the share of foreign direct investment (FDI) to GDP have dual-side impact: not high per-capital GDP and FDI bring the high immigration. 展开更多
关键词 YRD MIGRATION regional economic factors PANELDATA
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Ammonia volatilization losses and ^(15)N balance from urea applied to rice on a paddy soil 被引量:10
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作者 FAN Xiao-hui SONG Yong-sheng +2 位作者 LIN De-xi YANG Lin-zhang LUO Jia-fa 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第2期299-303,共5页
Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^... Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^+-N concentration in the field floodwater affecting ammonia loss were also investigated. Results show that the ammonia loss by volatilization accounted for 18.6%-38.7% of urea applied at different stages, the greatest loss took place when urea was applied at the tillering stage, the smallest at the ear bearing stage, and the intermediate loss at the basal stage. The greatest loss took place within 7 d following the fertilizer application. Ammonia volatilization losses at three fertilization stages were significantly correlated with the ammonium concentration in the field floodwater after the fertilizer was applied. ^15N balance experiment indicated that the use efficiency of urea by rice plants ranged between 24.4% and 28.1%. At the early stage of rice growth, the fertilizer nitrogen use efficiency was rather low, only about 12%. The total amount of nitrogen lost from different fertilization stages in the rice field was 44.1%-54.4%, and the ammonia volatilization loss was 25.4%-33.3%. Reducing ammonia loss is an important treatment for improving N use efficiency. 展开更多
关键词 ammonia volatilization UREA ^15N balance RICE influence factors Taihu region
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Regional differences of urbanization in China and its driving factors 被引量:5
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作者 LIN Wen Qi WU Meng He +6 位作者 ZHANG Yue ZENG Rong Jun ZHENG Xiao Jin SHAO Lei ZHAO Lu Yun LI Shao Xing TANG Yan 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第6期778-791,共14页
After more than 30 years of rapid urbanization, the overall urbanization rate of China reached 56.1% in 2015.However, despite China's rapid increase in its overall rate of urbanization, clear regional differences ... After more than 30 years of rapid urbanization, the overall urbanization rate of China reached 56.1% in 2015.However, despite China's rapid increase in its overall rate of urbanization, clear regional differences can be observed. Furthermore, inadequate research has been devoted to in-depth exploration of the regional differences in China's urbanization from a national perspective, as well as the internal factors that drive these differences. Using prefecture-level administrative units in China as the main research subject, this study illustrates the regional differences in urbanization by categorizing the divisions into four types based on their urbanization ratio and speed(high level: low speed; high level: high speed; low level: high speed; and low level: low speed). Next, we selected seven economic and geographic indicators and applied an ordered logit model to explore the driving factors of the regional differences in urbanization. A multiple linear regression model was then adopted to analyze the different impacts of these driving factors on regions with different urbanization types. The results showed that the regional differences in urbanization were significantly correlated to per capita GDP, industry location quotients, urban-rural income ratio,and time distance to major centers. In addition, with each type of urbanization, these factors were found to have a different driving effect. Specifically, the driving effect of per capita GDP and industry location quotients presented a marginally decreasing trend, while main road density appeared to have a more significant impact on cities with lower urbanization rates. 展开更多
关键词 Urbanization regional differences Driving factor Ordered logit Multiple linear regression
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Measuring Social Vulnerability to Natural Hazards in Beijing-Tianjin-Hebei Region,China 被引量:2
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作者 HUANG Jianyi SU Fei ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2015年第4期472-485,共14页
Social vulnerability in this study represents the differences between the capacity to cope with natural hazards and disaster losses suffered within and between places.The assessment of social vulnerability has been re... Social vulnerability in this study represents the differences between the capacity to cope with natural hazards and disaster losses suffered within and between places.The assessment of social vulnerability has been recognized as a critical step in understanding natural hazard risks and enhancing effective response capabilities.This article presents an initial study of the social vulnerability of the Beijing-Tianjin-Hebei(B-T-H) Region in China.The goal is to replicate and test the applicability of the United States Social Vulnerability Index(So VI) method in a Chinese cultural context.Thirty-nine variables adapted from the So VI were collected in relation to two aspects:socioeconomic vulnerability and built environment vulnerability.Using factor analysis,seven factors were extracted from the variable set:the structure of social development,the level of economic and government financial strength,social justice and poverty,family structure,the intensity of space development,the status of residential housing and transportation,and building structure.Factor scores were summed to get the final So VI scores and the most and least vulnerable units were identified and mapped.The highest social vulnerability is concentrated in the northwest of the study area.The least socially vulnerable areas are mainly distributed in the Beijing,Tianjin and Shijiazhuang core urban peripheral and central city areas of the prefecture-level cities.The results show that this method is a useful tool for revealing places that have a high level of vulnerability,in other words,areas which are more likely to face significant challenges in coping with a large-scale event.These findings could provide a scientific basis for policy making and the implementation of disaster prevention and mitigation in China. 展开更多
关键词 natural hazards social vulnerability factor analysis Beijing-Tianjin-Hebei Region
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Targeting of AUF1 to vascular endothelial cells as a novel anti-aging therapy
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作者 Jian HE Ya-Feng JIANG +7 位作者 Liu LIANG Du-jin WANG Wen-Xin WEI Pan-Pan JI Yao-Chan HUANG Hui SONG Xiao-Ling LU Yong-Xiang ZHAO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第8期515-523,共9页
Background Inhibition of aging of vascular endothelial cells (VECs) may delay aging and prolong life. The goal of this study was to prepare anti-CD31 monoclonal antibody conjugated PEG-modified liposomes containing ... Background Inhibition of aging of vascular endothelial cells (VECs) may delay aging and prolong life. The goal of this study was to prepare anti-CD31 monoclonal antibody conjugated PEG-modified liposomes containing the AU-rich region connecting factor 1 (AUF1) gene (CD31-PILs-AUF1) and to explore the effects of targeting CD31-PILs-AUF1 to aging VECs. Methods The mean particle sizes of various PEGylated immunoliposomes (PILs) were measured using a Zetasizer Nano ZS. Gel retardation assay was used to confirm whether PILs had encapsulated the AUF1 plasmid successfully. Fluorescence microscopy and flow cytometry were used to quantify binding of CD31-PILs-AUF1 to target cells. Flow cytometry was also used to analyze the cell cycles of aging bEnd3 cells treated with CD31-PILs-AUF1. We also developed an aging mouse model by treating mice with D-galactose. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the levels of interleuldn-6 (IL-6) and tumor necrosis factor-or (TNF-ct). The malondialdehyde (MDA) and the superoxide dismutase (SOD) levels were detected by commercial kits. Hematoxylin-eosin (HE) staining was used to determine whether treatment with CD31-PILs-AUF 1 was toxic to the mice. Results CD31-PILs-AUF 1 specifically could targeted bEnd3 VECs and increased the percentage of cells in the S and G2/M phases of aging bEnd3 cells. ELISA showed that content of the IL-6 and TNF-ct decreased in CD31-PILs-AUF1 group. The level of SOD increased, whereas MDA decreased in the CD31-PILs-AUF1 group. Additionally, CD31-PILs-AUF 1 was not toxic to the mice. Conclusion CD31-PILs-AUF 1 targets VECs and may delay their senescence. 展开更多
关键词 Aging AU-rich region connecting factor 1 PEGylated immunoliposomes Vascular endothelial ceils
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Estimation model of winter wheat disease based on meteorological factors and spectral information 被引量:4
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作者 Weiguo Li Yang Liu +1 位作者 Hua Chen Cheng Cheng Zhang 《Food Production, Processing and Nutrition》 2020年第1期41-47,共7页
Wheat scab(WS,Fusarium head blight),one of the most severe diseases of winter wheat in Yangtze-Huaihe river region,whose monitoring and timely forecasting at large scale would help to optimize pesticide spraying and a... Wheat scab(WS,Fusarium head blight),one of the most severe diseases of winter wheat in Yangtze-Huaihe river region,whose monitoring and timely forecasting at large scale would help to optimize pesticide spraying and achieve the purpose of reducing yield loss.In the present study,remote sensing monitoring on WS was conducted in 4 counties in Yangtze-Huaihe river region.Sensitive factors of WS were selected to establish the remote sensing estimation model of winter wheat scab index(WSI)based on interactions between spectral information and meteorological factors.The results showed that:1)Correlations between the daily average temperature(DAT)and daily average relative humidity(DAH)at different time scales and WSI were significant.2)There were positive linear correlations between winter wheat biomass,leaf area index(LAI),leaf chlorophyll content(LCC)and WSI.3)NDVI(normalized difference vegetation index),RVI(ratio vegetation index)and DVI(difference vegetation index)which had a good correlation with LAI,biomass and LCC,respectively,and could be used to replace them in modeling.4)The estimated values of the model were consistent with the measured values(RMSE=5.3%,estimation accuracy=90.46%).Estimation results showed that the model could efficiently estimate WS in Yangtze-Huaihe river region. 展开更多
关键词 Winter wheat scab Spectral information meteorological factor Remote sensing Yangtze-Huaihe river region
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Synergistic impacts of anthropogenic and biogenic emissions on summer surface O_3 in East Asia 被引量:4
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作者 Yu Qu Junling An Jian Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第3期520-530,共11页
A factor separation technique and an improved regional air quality model (RAQM) were applied to calculate synergistic contributions of anthropogenic volatile organic compounds (AVOCs),biogenic volatile organic com... A factor separation technique and an improved regional air quality model (RAQM) were applied to calculate synergistic contributions of anthropogenic volatile organic compounds (AVOCs),biogenic volatile organic compounds (BVOCs) and nitrogen oxides (NOx) to daily maximum surface O3(O3DM) concentrations in East Asia in summer (June to August 2000).The summer averaged synergistic impacts of AVOCs and NOx are dominant in most areas of North China,with a maximum of 60 ppbv,while those of BVOCs and NOx are notable only in some limited areas with high BVOC emissions in South China,with a maximum of 25 ppbv.This result implies that BVOCs contribute much less to summer averaged O3DM concentrations than AVOCs in most areas of East Asia at a coarse spatial resolution (1×1) although global emissions of BVOCs are much greater than those of AVOCs.Daily maximum total contributions of BVOCs can approach 20 ppbv in North China,but they can reach 40 ppbv in South China,approaching or exceeding those in some developed countries in Europe and North America.BVOC emissions in such special areas should be considered when O3 control measures are taken.Synergistic contributions among AVOCs,BVOCs and NOx significantly enhance O3 concentrations in the Beijing-Tianjin-Tangshan region and decrease them in some areas in South China.Thus,the total contributions of BVOCs to O3DM vary significantly from day to day and from location to location.This result suggests that O3 control measures obtained from episodic studies could be limited for long-term applications. 展开更多
关键词 regional air quality model volatile organic compounds O3 factor separation technique synergistic contribution
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