Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering se...Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering semi-urbanization. Nine types of urban development are presented according to the relations between semi-urbanization and urbanization, and China's urbanization is divided into five stages, namely, high incoordination, incoordination, low coordination, coordination, and high coordination. Results show that China's semi-urbanization rate varies significantly from one area to another; its order in 2010 from the highest to the lowest value was as follows: east, middle, west, and northeast. Urbanization and semi-urbanization rates in inland cities increase much faster than those in coastal cities. In addition, semi-urbanization displays a spatial pattern similar to that of urbanization across China, with the sole exception of the northeastern region. Through a spatial autocorrelation analysis, the spatial concentration of semi-urbanization is determined to be increasing. High-value concentration areas are expanding in the coastal east, whereas low-value concentration areas are growing in the northeast. Lastly, the evolution of China's urbanization model suggests a weakening trend of coordination between urbanization and semi-urbanization over the studied decade. Semi-urbanization can be viewed as a special production of China's hukou system, which restricts the permanent settlement of migrants in cities. As such, China's semi-urbanization trend is expected to exhibit a reversed U-shaped pattern as urbanization and citizenization develop.展开更多
Introduction: Pediatric Acute Kidney Injury (AKI) seems to be a major cause of morbidity and mortality in Subsahara Africa. However, data on its epidemiology are scare and mainly originate from tertiary and urban heal...Introduction: Pediatric Acute Kidney Injury (AKI) seems to be a major cause of morbidity and mortality in Subsahara Africa. However, data on its epidemiology are scare and mainly originate from tertiary and urban health facilities such as large university Teaching hospitals with a nephrology service. Objective: The aim of this study was to compare the epidemiology of pediatric AKI in urban and semi-urban health facility. Patients and method: We conducted a retrospective study of 16 months in a tertiary urban hospital (General Hospital of Douala) and a secondary semi-urban health facility (Region hospital of Buea). Diagnostic of AKI was done using usual criteria. Age, sex distribution, etiologies of AKI, access to dialysis, renal recovery at hospital discharge, at 1 and 3 months and patient survival at hospital discharge was compared. Results: A total of 31 patients were included (GD 17 and RHB 14). Boys were more prevalent in the semi-urban setting (86% Vs 47% p = 0.029). Median age was comparable in the both group although most semi-rural patient were older (6.5 Vs 10 years p = 0.093). Hospital acquired AKI was only found in urban setting and account for 40% of pediatric urban AKI. Malaria related AKI (mainly black water fever) and sepsis were the main etiologies of AKI in urban and semi-urban milieu. Dialysis access was the same but 30% of children could not access to it in urban setting compare to none in semi-urban area. Reasons of non-access to dialysis were lack of pediatric material and financial constraints. In Hospital mortality was the same but was more severe amount patient who could not receive dialysis. Among the survivor, CKD was only found in urban setting. Conclusion: Although mainly due to malaria, pediatric AKI differs from urban tertiary and semi-urban secondary health facility in Cameroon. Hospital acquired AKI is only found in urban setting where children are younger and less boys. AKI in urban setting seems to be more severe with less access to dialysis and more risks of CKD.展开更多
Atmospheric carbonyls were measured at a semi-urban site in Orléans, France, from October 2010to July2011. Formaldehyde, acetaldehyde and acetone were found to be the most abundant carbonyls, with average concent...Atmospheric carbonyls were measured at a semi-urban site in Orléans, France, from October 2010to July2011. Formaldehyde, acetaldehyde and acetone were found to be the most abundant carbonyls, with average concentrations of 3.1, 1.0, 2.0 ppb, respectively in summer, 2.3, 0.7, 2.2 ppb, respectively in autumn, 2.2, 1.0, 2.1 ppb, respectively in spring,and 1.5, 0.7, 1.1 ppb, respectively in winter. Photo-oxidation of volatile organic compounds(VOCs) was found to make a remarkable contribution to atmospheric carbonyls in the semi-urban site based on the distinct seasonal and diurnal variations of the carbonyls, as well as the significantly positive correlations between the carbonyls and ozone. The significantly negative correlations between NO x and O_3 as well as the carbonyls and the positive correlations between wind speed and O_3 as well as the carbonyls implied that the carbonyls and O_3 at the semi-urban site were probably formed during air mass transport from neighboring cities.展开更多
This paper uses empirical research conducted in Shanghai to answer these questions: What are the differences between the new generation of migrant workers and the previous generation of migrant workers? What influen...This paper uses empirical research conducted in Shanghai to answer these questions: What are the differences between the new generation of migrant workers and the previous generation of migrant workers? What influence do they have on China's politics? Surveys have shown that the new generation of migrant workers put a greater emphasis on personal space and quality of life. They also have a greater awareness of their individual rights. Additionally, they have a stronger desire to assimilate into the city. The ratio of remittances in relation to income among the new generation of migrant workers has decreased signiflcandy while their local spending has increased. Overall, the new migrant workers demonstrate a stronger tendency towards permanent migration. Local citizenship based on the hukou (household registration ) system is facing a crisis of legitimacy. The unrest among the new generation of migrant workers is a mixture of Marx-type labor unrest and Polanyi-type labor unrest, but the unrest is ultimately directed towards the state. The result will be a rise in the politics of citizenship in China.展开更多
Introduction:This study aims to examine the uptake and translocation of Cd,Cu,Fe,and Pb in different parts of three roadside plant species grown in the semi-urban of Jengka,Pahang,Malaysia.Methods:Heavy metal concentr...Introduction:This study aims to examine the uptake and translocation of Cd,Cu,Fe,and Pb in different parts of three roadside plant species grown in the semi-urban of Jengka,Pahang,Malaysia.Methods:Heavy metal concentrations were determined from various parts of Athyrium esculentum(AE),Chromolaena odorata(CO),and Lantana camara(LC).The bioconcentration factor(BCF)and translocation ratio of heavy metals from soils to plants were estimated.Results:Fe showed the highest metal concentration determined(<850 mg kg^(−1)),while Cd showed the lowest metal concentration observed(<0.12 mg kg^(−1))in all plants.Heavy metal concentration in the roadside plants was higher than metal determined in the same species from an uncontaminated site.Principal component analysis(PCA)suggests anthropogenic and natural sources of heavy metal.Plant roots slightly enriched by Cd and Pb(BCF<1),while the leaves absorbed and accumulated Cu and Fe(BCF>1).The translocation ratio of four metals suggests that absorption of the three plants had the rank:root>stem>leaves.Conclusion:The metals in the root zone transported weakly to the stem but more strongly mobilized to leaves when available in the stems.A comprehensive study of heavy metal concentration in a variety of roadside plants in the tropical area should be done in the future ensuring the precise source and translocation mechanisms.展开更多
基金National Natural Science Foundation of China,No.41371166
文摘Based on the prefecture-level data of the 2000 and 2010 national censuses, the spatial evolution of China's semi-urbanization is analyzed in this study. The stages of urbanization are re-examined by considering semi-urbanization. Nine types of urban development are presented according to the relations between semi-urbanization and urbanization, and China's urbanization is divided into five stages, namely, high incoordination, incoordination, low coordination, coordination, and high coordination. Results show that China's semi-urbanization rate varies significantly from one area to another; its order in 2010 from the highest to the lowest value was as follows: east, middle, west, and northeast. Urbanization and semi-urbanization rates in inland cities increase much faster than those in coastal cities. In addition, semi-urbanization displays a spatial pattern similar to that of urbanization across China, with the sole exception of the northeastern region. Through a spatial autocorrelation analysis, the spatial concentration of semi-urbanization is determined to be increasing. High-value concentration areas are expanding in the coastal east, whereas low-value concentration areas are growing in the northeast. Lastly, the evolution of China's urbanization model suggests a weakening trend of coordination between urbanization and semi-urbanization over the studied decade. Semi-urbanization can be viewed as a special production of China's hukou system, which restricts the permanent settlement of migrants in cities. As such, China's semi-urbanization trend is expected to exhibit a reversed U-shaped pattern as urbanization and citizenization develop.
文摘Introduction: Pediatric Acute Kidney Injury (AKI) seems to be a major cause of morbidity and mortality in Subsahara Africa. However, data on its epidemiology are scare and mainly originate from tertiary and urban health facilities such as large university Teaching hospitals with a nephrology service. Objective: The aim of this study was to compare the epidemiology of pediatric AKI in urban and semi-urban health facility. Patients and method: We conducted a retrospective study of 16 months in a tertiary urban hospital (General Hospital of Douala) and a secondary semi-urban health facility (Region hospital of Buea). Diagnostic of AKI was done using usual criteria. Age, sex distribution, etiologies of AKI, access to dialysis, renal recovery at hospital discharge, at 1 and 3 months and patient survival at hospital discharge was compared. Results: A total of 31 patients were included (GD 17 and RHB 14). Boys were more prevalent in the semi-urban setting (86% Vs 47% p = 0.029). Median age was comparable in the both group although most semi-rural patient were older (6.5 Vs 10 years p = 0.093). Hospital acquired AKI was only found in urban setting and account for 40% of pediatric urban AKI. Malaria related AKI (mainly black water fever) and sepsis were the main etiologies of AKI in urban and semi-urban milieu. Dialysis access was the same but 30% of children could not access to it in urban setting compare to none in semi-urban area. Reasons of non-access to dialysis were lack of pediatric material and financial constraints. In Hospital mortality was the same but was more severe amount patient who could not receive dialysis. Among the survivor, CKD was only found in urban setting. Conclusion: Although mainly due to malaria, pediatric AKI differs from urban tertiary and semi-urban secondary health facility in Cameroon. Hospital acquired AKI is only found in urban setting where children are younger and less boys. AKI in urban setting seems to be more severe with less access to dialysis and more risks of CKD.
基金supported by the Region Centre of France, the Chinese National Natural Science Foundation (No.21307008)Changsha Science and Technology Project (No.K1403048-31)
文摘Atmospheric carbonyls were measured at a semi-urban site in Orléans, France, from October 2010to July2011. Formaldehyde, acetaldehyde and acetone were found to be the most abundant carbonyls, with average concentrations of 3.1, 1.0, 2.0 ppb, respectively in summer, 2.3, 0.7, 2.2 ppb, respectively in autumn, 2.2, 1.0, 2.1 ppb, respectively in spring,and 1.5, 0.7, 1.1 ppb, respectively in winter. Photo-oxidation of volatile organic compounds(VOCs) was found to make a remarkable contribution to atmospheric carbonyls in the semi-urban site based on the distinct seasonal and diurnal variations of the carbonyls, as well as the significantly positive correlations between the carbonyls and ozone. The significantly negative correlations between NO x and O_3 as well as the carbonyls and the positive correlations between wind speed and O_3 as well as the carbonyls implied that the carbonyls and O_3 at the semi-urban site were probably formed during air mass transport from neighboring cities.
文摘This paper uses empirical research conducted in Shanghai to answer these questions: What are the differences between the new generation of migrant workers and the previous generation of migrant workers? What influence do they have on China's politics? Surveys have shown that the new generation of migrant workers put a greater emphasis on personal space and quality of life. They also have a greater awareness of their individual rights. Additionally, they have a stronger desire to assimilate into the city. The ratio of remittances in relation to income among the new generation of migrant workers has decreased signiflcandy while their local spending has increased. Overall, the new migrant workers demonstrate a stronger tendency towards permanent migration. Local citizenship based on the hukou (household registration ) system is facing a crisis of legitimacy. The unrest among the new generation of migrant workers is a mixture of Marx-type labor unrest and Polanyi-type labor unrest, but the unrest is ultimately directed towards the state. The result will be a rise in the politics of citizenship in China.
基金Funding was provided by the Universiti Teknologi MARA Cawangan Pahang.
文摘Introduction:This study aims to examine the uptake and translocation of Cd,Cu,Fe,and Pb in different parts of three roadside plant species grown in the semi-urban of Jengka,Pahang,Malaysia.Methods:Heavy metal concentrations were determined from various parts of Athyrium esculentum(AE),Chromolaena odorata(CO),and Lantana camara(LC).The bioconcentration factor(BCF)and translocation ratio of heavy metals from soils to plants were estimated.Results:Fe showed the highest metal concentration determined(<850 mg kg^(−1)),while Cd showed the lowest metal concentration observed(<0.12 mg kg^(−1))in all plants.Heavy metal concentration in the roadside plants was higher than metal determined in the same species from an uncontaminated site.Principal component analysis(PCA)suggests anthropogenic and natural sources of heavy metal.Plant roots slightly enriched by Cd and Pb(BCF<1),while the leaves absorbed and accumulated Cu and Fe(BCF>1).The translocation ratio of four metals suggests that absorption of the three plants had the rank:root>stem>leaves.Conclusion:The metals in the root zone transported weakly to the stem but more strongly mobilized to leaves when available in the stems.A comprehensive study of heavy metal concentration in a variety of roadside plants in the tropical area should be done in the future ensuring the precise source and translocation mechanisms.