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Comparing the carbon emission efficiency (CEE) of resource and non-resource-based cities in the Yellow River Basin (YRB) can guide their synergistic development and low-carbon transition. This study used the super-efficiency slacks-based measure (super-SBM) model to measure the CEE of cities in the YRB. Kernel density estimation and Theil index decomposition methods were used to explore the spatiotemporal evolutionary patterns, and a panel regression model was established to analyze the influencing factors of CEE. The research results showed that the CEE of the two types of cities have an overall upward trend in time, with a widening regional gap. Resource-based cities mainly displayed the characteristics of decentralized regional agglomeration, while non-resource-based cities mainly showed the characteristics of convergent regional agglomeration. Panel regression results showed that the levels of economic development, indus-trial structure, and population density are significantly positively correlated with CEE in the YRB, while foreign direct investment and resource endowment are significantly negatively correlated with CEE. Except for economic development and industrial structure, there is some variability in the contribution of the remaining influencing factors to the CEE of the resource and non-resource-based cities. The research results suggest developing classification measures for low-carbon transition in the YRB.

Urban agglomerations have become the core areas for carbon reduction in China since they account for around 75% of its total emissions. Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), and the Pearl River Delta (PRD), which are its most important poles of regional development and technological innovation, are key to achieving China's carbon peak emissions target. Based on the panel data of these three major urban agglomerations from 2003 to 2017, this study estimated the carbon emission efficiency (CEE) by the super-efficiency slacks-based measure (super-SBM) model and analyzed its spatiotemporal distribution pattern. The Dagum Gini coefficient was used to evaluate the difference in CEE between the three major agglomerations, while panel data models were established to analyze the impact of technological innovation on the three agglomerations. The overall CEE showed an upward trend during the study period, with significant spatial and temporal variations. Additionally, the main source of urban agglomeration difference in CEE evolved from inter-regional net differences to intensity of transvariation. While technological innovations are expected to significantly improve CEE, their effect varies among urban agglomerations. These results provide policymakers with insights on the collaborative planning of urban agglomerations and the low-carbon economy.

In recent years, with the public paying more and more attention to the problem of air pollution, the impact of air quality on migration has gradually become a growing concern. However, in the current context of cities' efforts to "attract talent" in China, research on the impact of air pollution on the flow or dwelling willingness of young talent is relatively limited. Based on the theory of planned behavior and from the perspective of subjective perception, this paper uses a regulated model to explore the impact mechanism of air pollution perception on young talent urban settlement intentions. Taking Hangzhou as a case, this study surveyed 987 individuals who were classified as young talent to explore the impact of air pollution perception on urban settlement intentions in China. The research shows that air pollution perception has a significant impact on young talent urban settlement intentions, and this impact is achieved through the intermediary effect of residential satisfaction. Place attachment of young talent to cities cannot significantly regulate the impact of air pollution perception on residential satisfaction, but it can significantly regulate the relationship between residential satisfaction and urban settlement intentions. That is to say, although place attachment cannot reduce the decline in residential satisfaction brought by air pollution perception, it can weaken the negative impact of air pollution perception on dwelling willingness through a decline in residential satisfaction. This paper contributes to a deeper understanding of the relationship between air quality and young talent settlement intentions.

Background: Previous studies indicate that migrant integration is associated with migrants' characteristics as well as restrictions and opportunities in receiving cities. However, the effect of receiving cities and the relationship between migrants and receiving cities have not been fully explored due to the lack of large samples from cities. The objective of this study is to examine the effects of receiving cities alone and their regulating role in the interaction with individual characteristics., Methods: Cross-city data on 154,044 Chinese domestic migrants above 15 years old in 289 cities from the 2017 China Migrants Dynamic Survey are used. Migrant integration is assessed by a four-dimensional model proposed by Esser, which is slightly adjusted according to the characteristics of Chinese migrants. A hierarchical linear model is used to measure the proportion of effects of city factors in migrant integration as well as the effects when city factors are considered alone and in interaction with individual factors., Results: The individual-level and city-level factors are responsible for 69.81% and 30.19% of the effect on migrant integration, respectively. City political factors do not affect migrant integration directly, and cities with larger sizes and higher wages can directly and significantly improve integration, while higher housing prices will directly inhibit integration. From the cross-level interaction of city and individual, different social, economic and political factors at the city level have an indirect impact on migrant integration by inhibiting or strengthening the effect of individual-level factors on migrant integration., Conclusion: This study is one of the first to show the effect of cities and the relationship between receiving cities and migrants on migrant integration by keeping the national context constant. It is necessary to weaken the social and economic privileges associated with a city's administrative level and reduce the negative impact of cities' social and economic conditions by implementing city agglomeration, developing advantageous industries and optimizing the industrial structure. It is also essential to improve migrants' socioeconomic capital through social support, occupation training and contiguous education., Competing Interests: The authors have declared that no competing interests exist.

Background: This study aimed to evaluate the discriminative abilities of glycosylated hemoglobin (HbA1c) and to examine the optimal HbA1c cutoff values for diabetes and prediabetes in Chinese adults., Methods: Data of a population-based cohort of Chinese adults aged ≥40 years living in Jiading District in Shanghai were used. At baseline, 9389 and 7241 participants were included to identify the optimal HbA1c cutoff values for diabetes and prediabetes, respectively using the 1999 World Health Organization criteria as reference. In addition, the follow-up data on incident diabetes of 4538 participants were used to determine the HbA1c cutoff value for prediabetes using the development of diabetes as reference. The discriminative abilities of HbA1c were evaluated using receiver operating characteristic (ROC) curves, and the optimal cutoff values were determined by Youden's index., Results: The areas under the ROC curves were 0.849 for diabetes, 0.614 for prediabetes using baseline data, and 0.648 for prediabetes using follow-up data. An HbA1c cutoff value of 6.0% had the largest Youden's index to diagnose diabetes with a sensitivity of 70.2% and a specificity of 87.4%. An HbA1c cutoff value of 5.6% was indicated for prediabetes using both baseline and follow-up data. However, the sensitivity and specificity were both low (55.4% and 61.1% using an oral glucose tolerance test as reference, 64.6% and 57.1% using incident diabetes as reference)., Conclusions: An HbA1c value ≥6.0% could be used to detect diabetes in Chinese adults aged ≥40 years. However, although an HbA1c value of 5.6% to 5.9% was indicated in this study, the overall discrimination of HbA1c for prediabetes was poor., (© 2020 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.)

Pollution with total petroleum hydrocarbons (TPHs) is a global concern and particularly in coastal environments. Polycyclic aromatic hydrocarbons (PAHs) are regarded as the most toxic components of TPHs and they can also be derived from other sources. Fangcheng Port is considered as a representative emerging coastal city in China, but the status, sources, and hazards to organisms and humans with respect to contamination with PAHs and TPHs are unknown in the coastal regions of this area. Therefore, in this study, we cloned cytochrome P450 family genes (CYP1A1, CYP3A, and CYP4) and heat shock protein 70 gene (HSP70) in the clam Meretrix meretrix as well as optimizing the method for measuring the 7-ethoxyresorufin O-deethylase activity. These molecular indicators and four specific physiological indexes were found to be appropriate biomarkers for indicating the harmful effects of PAHs and TPHs on clams after exposure to the crude oil water-soluble fraction. In field monitoring surveys, we found that the 2- and 3-ring PAHs were dominant in the clams whereas the 4- to 6-ring PAHs were dominant in the sediments at each site. The PAH levels (3.63-12.77 ng/g wet weight) in wild clams were lower, whereas the TPH levels (13.25-70.50 μg/g wet weight) were higher compared with those determined previous in China and elsewhere. The concentrations of PAHs and TPHs in the sediments (19.20-4215.76 ng/g and 3.65-866.40 μg/g dry weight) were moderate compared with those in other global regions. Diagnostic ratio analysis demonstrated that the PAHs were derived mainly from pyrogenic sources. The TPHs may have come primarily from industrial effluents, land and maritime transportation, or fishing activities. The Integrated Biomarker Response version 2 indexes indicated that the clams collected from site S5 exhibited the most harmful effects due to contamination by PAHs and TPHs. Human health risk assessments demonstrated that the risks due to PAHs and TPHs following the consumption of clams can be considered acceptable. Our results suggest that continuous monitoring of contamination by PAHs and TPHs is recommended in this emerging coastal city as well as assessing their human health risks., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The study was to investigate the prevalence of metabolic health in subjects with obesity in the Chinese population and to identify the determinants related to metabolic abnormality in obese individuals., Methods: 5013 subjects were recruited from seven provincial capitals in China. The obesity and metabolic status were classified based on body mass index (BMI) and the number of abnormalities in common components of metabolic syndrome., Results: 27.9% of individuals with obesity were metabolically healthy. The prevalence of the metabolically healthy obese (MHO) phenotype was significantly decreased with age in women (p trend < 0.001), but not significantly in men (p trend = 0.349). Central obesity (odds ratio [OR] = 4.07, 95% confidence interval [CI] = 1.93-8.59), longer sedentary time (OR = 1.97, 95%CI = 1.27-3.06), and with a family history of obesity related diseases (hypertension, diabetes, dyslipidemia) (OR = 1.85, 95%CI = 1.26-2.71) were significantly associated with having metabolic abnormality in obese individuals. Higher levels of physical activity and more fruit/vegetable intake had decreased ORs of 0.67 (95%CI = 0.45-0.98) and 0.44 (95%CI = 0.28-0.70), respectively., Conclusion: 27.9% of obese participants are in metabolic health. Central obesity, physical activity, sedentary time, fruits/vegetables intake and family history of diseases are the determinants associated with metabolic status in obesity.