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1.
Nat Commun ; 11(1): 2096, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350258

RESUMO

Many countries have implemented national climate policies to accomplish pledged Nationally Determined Contributions and to contribute to the temperature objectives of the Paris Agreement on climate change. In 2023, the global stocktake will assess the combined effort of countries. Here, based on a public policy database and a multi-model scenario analysis, we show that implementation of current policies leaves a median emission gap of 22.4 to 28.2 GtCO2eq by 2030 with the optimal pathways to implement the well below 2 °C and 1.5 °C Paris goals. If Nationally Determined Contributions would be fully implemented, this gap would be reduced by a third. Interestingly, the countries evaluated were found to not achieve their pledged contributions with implemented policies (implementation gap), or to have an ambition gap with optimal pathways towards well below 2 °C. This shows that all countries would need to accelerate the implementation of policies for renewable technologies, while efficiency improvements are especially important in emerging countries and fossil-fuel-dependent countries.

2.
Sci Total Environ ; 692: 361-370, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31351280

RESUMO

In 2013, the Chinese government announced its first air quality standard for PM2.5 (particulate matter with a diameter < 2.5 µm) which requires annual mean PM2.5 concentration to achieve the World Health Organization (WHO) interim target 1 of 35 µg/m3 nationwide including the most polluted region of Beijing-Tianjin-Hebei (BTH). Here, we explore the future mitigation pathways for the BTH region to investigate the possibility of air quality attainment by 2030 in that region, by developing two energy scenarios (i.e., baseline energy scenario and enhanced energy scenario) and two end-of-pipe scenarios (i.e., business as usual scenario and best available technology scenario) and simulating future air quality for different scenarios using the WRF/CMAQ model. Results showed that without stringent energy and industrial structure adjustment, even the most advanced end-of-pipe technologies did not allow the BTH region to attain the 35 µg/m3 target. Under the most stringent scenario that coupled the enhanced structure adjustment measures and the best available end-of-pipe measures, the emissions of SO2, NOx, PM2.5 and NMVOCs (nonmethane volatile organic compounds) were estimated to be reduced by 85%, 74%, 82% and 72%, respectively, in 2030 over the BTH region. As a result, the simulated annual mean PM2.5 concentrations in Beijing, Tianjin and Hebei could decline to 23, 28 and 28 µg/m3, respectively, all of which achieved the 35 µg/m3 target by 2030. Our study identified a feasible pathway to achieve the 2030 target and highlighted the importance of reshaping the energy and industrial structure of the BTH region for future air pollution mitigation.

3.
Environ Pollut ; 245: 1095-1106, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30682744

RESUMO

The Beijing, Tianjin and Hebei region (BTH) in China is a highly populated area that has recently experienced frequent haze episodes in winter. With high production capacities, the iron and steel industry (ISI) has long been a key source of air pollutants in BTH and is thus considered responsible for the degradation of local air quality. Here, we conducted a cross-disciplinary research combining the Weather Research and Forecasting with Chemistry (WRF/Chem) model, the multiregional input-output model (MRIO) and the health assessment model to explore the impacts of the ISI on air pollution in the BTH region in January 2012. Our results show large increases in air pollution due to direct ISI emissions, with up to a 90 µg/m3 monthly average of fine particulate matter (PM2.5) and sulfur dioxide (SO2) in eastern Tangshan and western Handan. In addition to direct emissions, the ISI has induced large quantities of indirect emissions from upstream sectors (e.g., the electricity and transportation sectors), leading to PM2.5, SO2 and NOx increases of 2-10 µg/m3 in BTH. Considering the direct and indirect emissions, we estimated that 275 (233-313) PM2.5-related mortalities occurred in January, and approximately 42% of these premature deaths occurred in Tangshan. A high rate of premature deaths also occurred in urban Beijing due to its high population density. Revealing the great health burden caused by the ISI, our results underscore the necessity for the Chinese government to reduce air pollutant emissions from the ISI and its upstream industries in BTH.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Metalurgia , Material Particulado/análise , Dióxido de Enxofre/análise , Pequim , China , Cidades , Humanos , Ferro , Estações do Ano , Aço , Tempo (Meteorologia)
4.
Drug Deliv ; 25(1): 388-397, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29378465

RESUMO

Glioma, one of the most common brain tumors, remains a challenge worldwide. Due to the specific biological barriers such as blood-brain barrier (BBB), cancer stem cells (CSCs), tumor associated macrophages (TAMs), and vasculogenic mimicry channels (VMs), a novel versatile targeting delivery for anti-glioma is in urgent need. Here, we designed a hyaluronic acid (HA) ion-pairing nanoparticle. Then, these nanoparticles were encapsulated in liposomes, termed as DOX-HA-LPs, which showed near-spherical morphology with an average size of 155.8 nm and uniform distribution (PDI = 0.155). HA was proven to specifically bind to CD44 receptor, which is over-expressed on the surface of tumor cells, other associated cells (such as CSCs and TAMs) and VMs. We systematically investigated anti-glioma efficacy and mechanisms in vivo and in vitro. The strong anti-glioma efficacy could attribute to the accumulation in glioma site and the regulation of tumor microenvironment with depletion of TAMs, inhibition of VMs, and elimination of CSCs.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Nanopartículas/administração & dosagem , Microambiente Tumoral/efeitos dos fármacos , Animais , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Ácido Hialurônico/metabolismo , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/metabolismo , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Microambiente Tumoral/fisiologia
5.
J Control Release ; 271: 21-30, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29277681

RESUMO

The chemotherapy of aggressive breast tumor is usually accompanied by a poor prognosis because of the metastasis of tumor cells. Thus, it is important to simultaneously enhance antitumor and anti-metastasis efficacy. Fibronectin and its complexes are expressed on the walls of tumor vessels and in tumor stroma. Moreover, the expression of fibronectin in metastatic sites is even higher than that in primary tumors. Herein, we designed a fibronectin-targeting CREKA-modified liposomal doxorubicin (CREKA-Lipo-Dox) for the therapy of metastatic breast tumor. CREKA-Lipo was uniformly formed with high entrapment efficiency. It exhibited longer blood circulation time compared with free Dox, and there was no significant change compared with PEG-Lipo-Dox. Immunofluorescence results revealed that the CREKA-Lipo-Dox could specifically bind to fibronectin in the tumor vessels and tumor stroma. The antitumor and anti-metastasis efficacy of CREKA-loaded liposome was more obvious than that of free Dox or unmodified Dox-Lipo. Taken together, binding fibronectin by CREKA could be an attractive therapeutic strategy for metastatic breast cancer in the future.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/análogos & derivados , Fibronectinas/metabolismo , Oligopeptídeos/administração & dosagem , Animais , Antibióticos Antineoplásicos/farmacocinética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Feminino , Masculino , Camundongos Endogâmicos BALB C , Oligopeptídeos/farmacocinética , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacocinética , Ratos Sprague-Dawley
6.
Data Brief ; 10: 44-46, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27942567

RESUMO

The data files contain the assumptions and results for the construction of cumulative availability curves for coal, oil and gas for the five Shared Socioeconomic Pathways. The files include the maximum availability (also known as cumulative extraction cost curves) and the assumptions that are applied to construct the SSPs. The data is differentiated into twenty regions. The resulting cumulative availability curves are plotted and the aggregate data as well as cumulative availability curves are compared across SSPs. The methodology, the data sources and the assumptions are documented in a related article (N. Bauer, J. Hilaire, R.J. Brecha, J. Edmonds, K. Jiang, E. Kriegler, H.-H. Rogner, F. Sferra, 2016) [1] under DOI: http://dx.doi.org/10.1016/j.energy.2016.05.088.

7.
Biomaterials ; 108: 44-56, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27619239

RESUMO

Finding effective cures against aggressive malignancy remains a major challenge in cancer chemotherapy. Here, we report a "tadpole"-like peptide by covalently conjugating the alanine-alanine-asparagine "tail" residual to the cyclic tumor homing peptide iRGD (CCRGDKGPDC) to afford nRGD, which significantly enhanced tumoricidal effects of doxorubicin, by either co-administered as a physical mixture or as a targeting ligand covalently conjugated to the liposomal carrier. Given twice at an equivalent dose of 5 mg/kg, doxorubicin loaded liposomes modified with nRGD (nRGD-Lipo-Dox) showed excellent antitumor efficacy in 4T1 breast cancer mice, of which 44.4% remained alive for over 90 days without recurrence during the period of investigation. The dramatic improvement in antitumor efficacy was attributed to nRGD-Lipo-Dox which appeared to specifically interact with tumor vascular endothelial cells to achieve efficient tumor penetration, and modulate tumor microenvironment with depletion of tumor associated macrophages.


Assuntos
Doxorrubicina/administração & dosagem , Sinergismo Farmacológico , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Oligopeptídeos/administração & dosagem , Microambiente Tumoral/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Combinação de Medicamentos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/síntese química , Engenharia de Proteínas/métodos , Resultado do Tratamento
8.
Sci China C Life Sci ; 48 Spec No: 955-64, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16512217

RESUMO

This paper gives a quantitative analysis on the non-CO2 emissions related to energy demand, energy activities and land use change of six scenarios with different development pattern in 2030 and 2050 based on IPAC emission model. The various mitigation technologies and policies are assessed to understand the corresponding non-CO2 emission reduction effect. The research shows that the future non-CO2 emissions of China will grow along with increasing energy demand, in which thermal power and transportation will be the major emission and mitigation sectors. During the cause of future social and economic development, the control and mitigation of non-CO2 emissions is a problem as challenging and pressing as that of CO2 emissions. This study indicates that the energy efficiency improvement, renewable energy, advanced nuclear power generation, fuel cell, coal-fired combined cycle, clean coal and motor vehicle emission control technologies will contribute to non-CO2 emissions control and mitigation.


Assuntos
Poluentes Atmosféricos , Dióxido de Carbono , Fontes Geradoras de Energia , Emissões de Veículos , Poluição do Ar , China , Previsões , Humanos , Modelos Teóricos , Formulação de Políticas
9.
Sci China C Life Sci ; 48 Suppl 2: 955-64, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20549450

RESUMO

This paper gives a quantitative analysis on the non-CO(2) emissions related to energy demand, energy activities and land use change of six scenarios with different development pattern in 2030 and 2050 based on IPAC emission model. The various mitigation technologies and policies are assessed to understand the corresponding non-CO(2) emission reduction effect. The research shows that the future non-CO(2) emissions of China will grow along with increasing energy demand, in which thermal power and transportation will be the major emission and mitigation sectors. During the cause of future social and economic development, the control and mitigation of non-CO(2) emissions is a problem as challenging and pressing as that of CO(2) emissions. This study indicates that the energy efficiency improvement, renewable energy, advanced nuclear power generation, fuel cell, coal-fired combined cycle, clean coal and motor vehicle emission control technologies will contribute to non-CO(2) emissions control and mitigation.


Assuntos
Dióxido de Carbono/química , Conservação dos Recursos Naturais , Nitrogênio/química , Poluentes Atmosféricos/química , Poluição do Ar , China , Mudança Climática , Fontes Geradoras de Energia , Monitoramento Ambiental/métodos , Previsões , Humanos , Modelos Teóricos , Formulação de Políticas , Emissões de Veículos
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