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1.
BMC Public Health ; 24(1): 1234, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704550

RESUMO

"National Civilized City" (NCC) is regarded as China's highest honorary title and most valuable city brand. To win and maintain the "golden city" title, municipal governments must pay close attention to various key appraisal indicators, mainly environmental ones. In this study we verify whether cities with the title are more likely to mitigate SO2 pollution. We adopt the spatial Durbin difference-in-differences (DID) model and use panel data of 283 Chinese cities from 2003 to 2018 to analyze the local (direct) and spillover effects (indirect) of the NCC policy on SO2 pollution. We find that SO2 pollution in Chinese cities is not randomly distributed in geography, suggesting the existence of spatial spillovers and possible biased estimates. Our study treats the NCC policy as a quasi-experiment and incorporates spatial spillovers of NCC policy into a classical DID model to verify this assumption. Our findings show: (1) The spatial distribution of SO2 pollution represents strong spatial spillovers, with the most highly polluted regions mainly situated in the North China Plain. (2) The Moran's I test results confirms significant spatial autocorrelation. (3) Results of the spatial Durbin DID models reveal that the civilized cities have indeed significantly mitigated SO2 pollution, indicating that cities with the honorary title are acutely aware of the environment in their bid to maintain the golden city brand. As importantly, we notice that the spatial DID term is also significant and negative, implying that neighboring civilized cities have also mitigated their own SO2 pollution. Due to demonstration and competition effects, neighboring cities that won the title ostensibly motivates local officials to adopt stringent policies and measures for lowering SO2 pollution and protecting the environment in competition for the golden title. The spatial autoregressive coefficient was significant and positive, indicating that SO2 pollution of local cities has been deeply affected by neighbors. A series of robustness check tests also confirms our conclusions. Policy recommendations based on the findings for protecting the environment and promoting sustainable development are proposed.


Assuntos
Poluição do Ar , Cidades , Análise Espacial , Dióxido de Enxofre , China , Poluição do Ar/prevenção & controle , Poluição do Ar/legislação & jurisprudência , Poluição do Ar/análise , Humanos , Dióxido de Enxofre/análise , Política Ambiental/legislação & jurisprudência , Poluentes Atmosféricos/análise
2.
Animals (Basel) ; 14(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38672292

RESUMO

Eggshell gloss is an important characteristic for the manifestation of eggshell appearance. However, no study has yet identified potential candidate genes for eggshell gloss between high-gloss (HG) and low-gloss (LG) chickens. The aim of this study was to perform a preliminary investigation into the formation mechanism of eggshell gloss and to identify potential genes. The eggshell gloss of 300-day-old Rhode Island Red hens was measured from three aspects. Uterine tissues of the selected HG and LG (n = 5) hens were collected for RNA-seq. Blood samples were also collected for whole-genome resequencing (WGRS). RNA-seq analysis showed that 150 differentially expressed genes (DEGs) were identified in the uterine tissues of HG and LG hens. These DEGs were mainly enriched in the calcium signaling pathway and the neuroactive ligand-receptor interaction pathway. Importantly, these two pathways were also significantly enriched in the WGRS analysis results. Further joint analysis of WGRS and RNA-seq data revealed that 5-hydroxytryptamine receptor 1F (HTR1F), zinc finger protein 536 (ZNF536), NEDD8 ubiquitin-like modifier (NEDD8), nerve growth factor (NGF) and calmodulin 1 (CALM1) are potential candidate genes for eggshell gloss. In summary, our research provides a reference for the study of eggshell gloss and lays a foundation for improving egg glossiness in layer breeding.

3.
Inorg Chem ; 61(48): 19543-19551, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36413484

RESUMO

A series of conformationally rigid (Zn-salphen)2 complexes with a planar bridging component (xanthene or dibenzofuran) are described. Conformational changes for these assemblies are essentially limited to the axial rotation of the Zn-salphen moieties; however, such geometric constraints crucially permit the subtle tuning of the intermetallic separation and geometry to potentially enhance catalytic activity (and cooperative effects). The complexes have been investigated as catalysts in conjunction with nBu4NI for the coupling of CO2 with epoxides. Selected dibenzofuran derivatives are significantly more active for the production of cyclic carbonate than their mononuclear analogues under identical conditions and concentrations of Zn sites. High initial turnover frequencies (up to 29 000 h-1; 14 500 h-1 per Zn, using 10 bar of CO2 at 95 °C) and excellent efficiencies under mild conditions (1 bar of CO2 at 55 °C) have been achieved. Kinetic studies using in situ (ReactIR) spectroscopy and density functional theory calculations have been performed, which reveal the existence of an intramolecular rate component and a preference for the cooperative pathway as well as transition states that depict the Zn sites operating in tandem. Taken together, these results provide strong evidence of cooperative reactivity in these Zn2 catalysts.

4.
Environ Sci Pollut Res Int ; 28(16): 20393-20407, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33405127

RESUMO

To recover the global economy, China in 2013 called for a new global strategy, namely, "One Belt and One Road Initiative" (BRI), which aims at reinforcing regional economic cooperation, enhancing regional collaboration of economic policy, and realizing the goal of rapid economic development of member countries. Accelerating industrialization not only has been recognized as an effective way to stimulate economic development, but also lead to the serious issue of environmental pollution, which challenges the environmental sustainability. In this study, we focus on the industrializing region as a study area to investigate the driving factors of environmental pollution. Technically, we utilized satellite observation technique to obtain NO2 columns data to denote environmental pollution and then applied dynamic spatial panel data models to evaluate what affects NO2 pollution levels. The findings are the following. (1) NO2 pollution exhibits significant and positive spatial autocorrelation, indicating spatial spillovers of NO2 pollution. (2) Lebanon, Bangladesh, Kyrgyzstan, and India experienced the largest increase of NO2 pollution while NO2 pollution in Singapore, Hungary, Greece, and Ukraine was substantially reduced. (3) The results of the dynamic spatial panel data models show that both the time dynamics effects and the spatial spillover effects are found to be significant and positive. In other words, both effects should be considered. Population is the foremost contributor to increase NO2 pollution while urbanization is an effective way to reduce pollution. An EKC relationship between NO2 pollution and per capita income was verified. Besides, industrialization, foreign direct investment, and trade openness have positive impacts on NO2 pollution.


Assuntos
Análise de Dados , Dióxido de Nitrogênio , Bangladesh , China , Desenvolvimento Econômico , Poluição Ambiental , Grécia , Hungria , Índia , Quirguistão , Líbano , Singapura , Análise Espacial , Ucrânia
5.
Environ Sci Pollut Res Int ; 27(27): 33951-33964, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32542567

RESUMO

China has suffered from extensive and serious SO2 pollution. The central and provincial governments have reinforced environmental awareness by increasing fiscal expenditure for environmental protection for years. This paper extended an environmental Kuznets curve (EKC) framework to evaluate the direct and indirect spillover effects of environmental awareness of provincial governments on SO2 emissions, applying spatial econometric models. The empirical findings are as follows. (1) There exists an inverted U-shaped curve. Of 30 Chinese provinces, only 9 provinces, namely, 8 eastern provinces and Inner Mongolia, have passed the turning point at about 53,000 Yuan while the rest 21 provinces have not yet. (2) Expenditure for environmental protection is negatively correlated with SO2 pollution. In other words, environmental awareness of governments contributes to substantially reducing SO2 emissions. Besides, significant and negative spillover effects of environmental awareness are found, implying that provinces follow suit if neighboring provinces enhance environmental awareness by increasing spending on environmental protection, thereby reducing SO2 emissions. (3) The SO2 reduction policy implemented by the central government is found to have a negative impact on SO2 emissions, implying that the policy effectively works. To conclude, the central and provincial governments play pivotal roles in addressing the problem of SO2 pollution in China. Hence, more expenditure for environmental protection cannot be overstated for China's environmental quality improvements and sustainable development.


Assuntos
Gastos de Capital , Poluição Ambiental/análise , China , Governo , Modelos Econométricos
6.
J Environ Manage ; 268: 110667, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32383661

RESUMO

The research on SO2 pollution in China has been hotly debated over the past decades. Different from the existing studies, this work employs satellite observed SO2 columns from 2005 to 2016 and applies a spatial econometric approach to investigate the socio-economic influencing factors of SO2 pollution of 270 prefecture-level cities in China. The findings are as follows. (1) SO2 pollution over China exhibits a significant and positive spatial autocorrelation. (2) The most polluted area is concentrated on the North China Plain. However, SO2 pollution over China has been reduced gradually during the sample period, implying that overall environmental quality in China has been substantially improved. (3) Besides, the results of spatial econometric models are not in support of "pollution haven hypothesis". On the contrary, the pollution halo effect of foreign direct investment works well and contributes to reducing SO2 pollution in China. Moreover, we find that urban economic levels and innovative capability are negatively correlated with SO2 pollution, indicating that economic growth and an increase in innovation can help improve environmental quality. On contrast, the share of the secondary industry, urbanization and transportation are found to have positive impacts, indicating that they are three main contributors to SO2 pollution in China.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , China , Cidades , Monitoramento Ambiental , Poluição Ambiental , Material Particulado , Fatores Socioeconômicos , Análise Espacial
7.
Inorg Chem ; 56(19): 11990-11997, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28933542

RESUMO

Metastable rocksalt structured Ge2Sb2Te5 is the most widely used phase-change material for data storage, yet the atomic arrangements of which are still under debate. In this work, we have proposed metastable stacking-polymorphism in cubic Ge2Sb2Te5 based on first-principles calculations. Our results show that cubic Ge2Sb2Te5 is actually polymorphic, varying from randomly distributed vacancies to highly ordered vacancy layers; consequently, the electrical property varies between metallic and semiconducting. These different atomic stackings of cubic Ge2Sb2Te5 can be obtained at different experimental synthetic conditions. The concept of stacking-polymorphic Ge2Sb2Te5 provides important fundamentals for metastable Ge2Sb2Te5 and is useful for tuning the performance of the phase-change materials.

8.
Chem Commun (Camb) ; 52(5): 1017-20, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26594031

RESUMO

By adopting a shape-persistent bimetallic design approach, high initial molecular turnover frequencies (up to 14,800 h(-1)) for coupling of CO2 with epoxides in conjunction with (n)Bu4NI, plus excellent yields under mild conditions (1 bar of CO2, 45 °C) have been achieved for catalysts containing cofacial Zn-salphen units.

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