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2.
J Environ Manage ; 250: 109527, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521919

RESUMO

This paper argues for an efficient pollution tax rate system that reflects the differentiation of marginal health damages of the individual emission sources. Although China is the first country in the world to launch a regionally differentiated pollution tax rate program, due to the absence of marginal damage estimation, whether this policy is efficient and equitable remains unknown. In this paper, we build an Integrated Assessment Model to measure the marginal damage of SO2, NOx and PM2.5 emitted from 38 coal-fired power plants in the Beijing-Tianjin-Hebei region, and evaluate the policy performance of tax rate systems with different differentiation magnitudes. Results show that the spatial variations are huge, the range of marginal health damages of coal-fired power plants in the BTH region between the lowest and highest emission source is $2375 to $33245 per ton for SO2, $307 to $4984 per ton for NOx, and $11513 - $163126 per ton for PM2.5. Shifting from the uniform tax rate system to the current partially differentiated tax rate system will increase the total health benefits by 51.6% but with some regions worse-off than the uniform tax rate system. If we incorporate the source-specific variations of marginal health damages into the tax rate system, such a fully differentiated tax rate system will further increase the total health benefits of current partially differentiated tax rate system by 43.1% with every region better-off. Furthermore, even though the policy benefits of both differentiated tax rate systems are much more unequally distributed than uniform tax rates, their impacts on environmental inequalities are better than the uniform tax rate system. Because uniform tax rate systems do not offset the original inequalities of environmental health burdens while differentiated tax rate systems achieve this buy efficiently allocate mitigation targets among regions with different burdens.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Pequim , China , Monitoramento Ambiental , Material Particulado
3.
Nature ; 567(7749): 516-520, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30818324

RESUMO

The nitrogen cycle has been radically changed by human activities1. China consumes nearly one third of the world's nitrogen fertilizers. The excessive application of fertilizers2,3 and increased nitrogen discharge from livestock, domestic and industrial sources have resulted in pervasive water pollution. Quantifying a nitrogen 'boundary'4 in heterogeneous environments is important for the effective management of local water quality. Here we use a combination of water-quality observations and simulated nitrogen discharge from agricultural and other sources to estimate spatial patterns of nitrogen discharge into water bodies across China from 1955 to 2014. We find that the critical surface-water quality standard (1.0 milligrams of nitrogen per litre) was being exceeded in most provinces by the mid-1980s, and that current rates of anthropogenic nitrogen discharge (14.5 ± 3.1 megatonnes of nitrogen per year) to fresh water are about 2.7 times the estimated 'safe' nitrogen discharge threshold (5.2 ± 0.7 megatonnes of nitrogen per year). Current efforts to reduce pollution through wastewater treatment and by improving cropland nitrogen management can partially remedy this situation. Domestic wastewater treatment has helped to reduce net discharge by 0.7 ± 0.1 megatonnes in 2014, but at high monetary and energy costs. Improved cropland nitrogen management could remove another 2.3 ± 0.3 megatonnes of nitrogen per year-about 25 per cent of the excess discharge to fresh water. Successfully restoring a clean water environment in China will further require transformational changes to boost the national nutrient recycling rate from its current average of 36 per cent to about 87 per cent, which is a level typical of traditional Chinese agriculture. Although ambitious, such a high level of nitrogen recycling is technologically achievable at an estimated capital cost of approximately 100 billion US dollars and operating costs of 18-29 billion US dollars per year, and could provide co-benefits such as recycled wastewater for crop irrigation and improved environmental quality and ecosystem services.


Assuntos
Agricultura/métodos , Fertilizantes/análise , Fertilizantes/provisão & distribução , Ciclo do Nitrogênio , Nitrogênio/análise , Nitrogênio/provisão & distribução , Qualidade da Água/normas , Agricultura/estatística & dados numéricos , Animais , China , Ecossistema , Monitoramento Ambiental , Abastecimento de Alimentos/métodos , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Poluentes Químicos da Água/análise , Poluição da Água/análise
4.
Nat Med ; 25(3): 433-438, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30742121

RESUMO

Artificial intelligence (AI)-based methods have emerged as powerful tools to transform medical care. Although machine learning classifiers (MLCs) have already demonstrated strong performance in image-based diagnoses, analysis of diverse and massive electronic health record (EHR) data remains challenging. Here, we show that MLCs can query EHRs in a manner similar to the hypothetico-deductive reasoning used by physicians and unearth associations that previous statistical methods have not found. Our model applies an automated natural language processing system using deep learning techniques to extract clinically relevant information from EHRs. In total, 101.6 million data points from 1,362,559 pediatric patient visits presenting to a major referral center were analyzed to train and validate the framework. Our model demonstrates high diagnostic accuracy across multiple organ systems and is comparable to experienced pediatricians in diagnosing common childhood diseases. Our study provides a proof of concept for implementing an AI-based system as a means to aid physicians in tackling large amounts of data, augmenting diagnostic evaluations, and to provide clinical decision support in cases of diagnostic uncertainty or complexity. Although this impact may be most evident in areas where healthcare providers are in relative shortage, the benefits of such an AI system are likely to be universal.


Assuntos
Aprendizado Profundo , Diagnóstico por Computador , Registros Eletrônicos de Saúde , Processamento de Linguagem Natural , Pediatria , Adolescente , Inteligência Artificial , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Recém-Nascido , Aprendizado de Máquina , Masculino , Estudo de Prova de Conceito , Reprodutibilidade dos Testes , Estudos Retrospectivos
6.
J Environ Manage ; 219: 208-217, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29738936

RESUMO

Low-carbon transition in the non-electric energy sector, which includes transport and heating energy, is necessary for achieving the 2 °C target. Meanwhile, as non-electric energy accounts for over 60% of total water consumption in the energy supply sector, it is vital to understand future water trends in the context of decarbonization. However, few studies have focused on life-cycle water impacts for non-electric energy; besides, applying conventional LCA methodology to assess non-electric energy has limitations. In this paper, a Multi-Regional Hybrid Life-Cycle Assessment (MRHLCA) model is built to assess total CO2 emissions and water consumption of 6 non-electric energy technologies - transport energy from biofuel and gasoline, heat supply from natural gas, biogas, coal, and residual biomass, within 7 major emitting economies. We find that a shift to natural gas and residual biomass heating can help economies reduce 14-65% CO2 and save more than 21% water. However, developed and developing economies should take differentiated technical strategies. Then we apply scenarios from IMAGE model to demonstrate that if economies take cost-effective 2 °C pathways, the water conservation synergy for the whole energy supply sector, including electricity, can also be achieved.


Assuntos
Conservação dos Recursos Hídricos , Abastecimento de Água , Carbono , Carvão Mineral , Eletricidade , Gás Natural
7.
Lancet Planet Health ; 2(4): e151-e161, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29615216

RESUMO

BACKGROUND: Except for comparing the implementation costs of the Paris Agreement with potential health benefits at the national levels, previous studies have not explored the health impacts of the nationally determined contributions (NDCs) by countries and in regional details. In this Lancet Countdown study, we aimed to estimate and monetise the health benefits of China's NDCs in the electric power generation sector, and then compare them with the implementation costs, both at the national and regional levels. METHODS: In this modelling study, we linked the Multi-regional model for Energy Supply system and their Environmental ImpaCts, the Multi-resolution Emission Inventory for China model, the offline-coupled Weather Research and Forecasting model, the Community Multiscale Air Quality model, and the Integrated Health Impact Assessment model with a time scope from 2010 to 2050. We calculated the PM2·5 concentrations and compared the health impacts and implementation costs between two scenarios that reflect CO2 and air pollutant emissions-the reference (REF) scenario (no climate policy) and the NDC scenario (100% realisation of NDC targets: CO2 emission intensity needs to be about 40% below 2010 emissions by 2030 [roughly 35% below 2030 emissions in REF], and about 90% below 2010 emissions by 2050 [roughly 96% below 2050 emissions in REF]). FINDINGS: Under a comparatively optimistic health benefits valuation condition, at the national level, 18-62% of implementation costs could be covered by the health benefits in 2030. In 2050, the overall health benefits would substantially increase to 3-9 times of the implementation costs. However, northwest China would require the highest implementation costs and will also have more premature deaths because of a more carbon-intensive energy structure than business as usual. By 2030, people in northwest China (especially in Gansu, Shaanxi, and Xinjiang provinces) would need to bear worse air quality, and 10 083 (95% CI 3419-16 138) more premature deaths annually. This undesirable situation would diminish by about 2050. A solution that assumes no growth in air pollutant emissions in 2030 at the regional level is technically feasible, but would not be cost-effective. INTERPRETATION: Our results suggest that cost-benefit analysis of climate policy that omits regional air pollution could greatly underestimate benefits. A compensation mechanism for inter-regional interests (including financial, technological, and knowledge support) should be established for regions that give up their human health benefits for the sake of the whole nation to realise the climate change targets. FUNDING: National Natural Science Foundation of China and Cyrus Tang Foundation.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Dióxido de Carbono/análise , Mudança Climática , Recuperação e Remediação Ambiental/métodos , Material Particulado/análise , Centrais Elétricas , China , Humanos , Modelos Teóricos , Tamanho da Partícula
10.
Cell ; 172(5): 1122-1131.e9, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29474911

RESUMO

The implementation of clinical-decision support algorithms for medical imaging faces challenges with reliability and interpretability. Here, we establish a diagnostic tool based on a deep-learning framework for the screening of patients with common treatable blinding retinal diseases. Our framework utilizes transfer learning, which trains a neural network with a fraction of the data of conventional approaches. Applying this approach to a dataset of optical coherence tomography images, we demonstrate performance comparable to that of human experts in classifying age-related macular degeneration and diabetic macular edema. We also provide a more transparent and interpretable diagnosis by highlighting the regions recognized by the neural network. We further demonstrate the general applicability of our AI system for diagnosis of pediatric pneumonia using chest X-ray images. This tool may ultimately aid in expediting the diagnosis and referral of these treatable conditions, thereby facilitating earlier treatment, resulting in improved clinical outcomes. VIDEO ABSTRACT.


Assuntos
Aprendizado Profundo , Diagnóstico por Imagem , Pneumonia/diagnóstico , Criança , Humanos , Pneumonia/diagnóstico por imagem , Curva ROC , Reprodutibilidade dos Testes , Tomografia de Coerência Óptica
11.
Lancet ; 391(10120): 581-630, 2018 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-29096948
12.
J Mol Cell Biol ; 9(4): 289-301, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28655163

RESUMO

Mesenchymal stem cells (MSCs) have been demonstrated to have promising therapeutic benefits for a variety of neurological diseases; however, the underlying mechanisms are poorly understood. Here, we showed that intravitreal infusion of MSCs promoted retinal ganglion cell (RGC) survival in a mouse model of acute glaucoma, with significant inhibition of microglial activation, production of TNF-α, IL-1ß, and reactive oxygen species, as well as caspase-8 and caspase-3 activation. In vitro, MSCs inhibited both caspase-8-mediated RGC apoptosis and microglial activation, partly via the action of stanniocalcin 1 (STC1). Furthermore, we found that microRNA-21a-5p (miR-21) and its target, PDCD4, were essential for STC1 production and the neuroprotective property of MSCs in vitro and in vivo. Importantly, miR-21 overexpression or PDCD4 knockdown augmented MSC-mediated neuroprotective effects on acute glaucoma. These data highlight a previously unrecognized neuroprotective mechanism by which the miR-21/PDCD4 axis induces MSCs to secrete STC1 and other factors that exert neuroprotective effects. Therefore, modulating the miR-21/PDCD4 axis might be a promising strategy for clinical treatment of acute glaucoma and other neurological diseases.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Glaucoma/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Células Ganglionares da Retina/citologia , Transdução de Sinais , Doença Aguda , Animais , Proteínas Reguladoras de Apoptose/genética , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Glaucoma/genética , Glaucoma/metabolismo , Glaucoma/patologia , Injeções Intravítreas , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neuroproteção , Proteínas de Ligação a RNA/genética , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Regulação para Cima
13.
Environ Sci Technol ; 49(24): 13921-8, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26561867

RESUMO

This paper has changed the vague understanding that "the short-lived buildings have huge environmental footprints (EF)" into a concrete one. By estimating the annual floor space of buildings demolished and calibrating the average building lifetime in China, this paper compared the EF under various assumptive extended buildings' lifetime scenarios based on time-series environmental-extended input-output model. Results show that if the average buildings' lifetime in China can be extended from the current 23.2 years to their designed life expectancy, 50 years, in 2011, China can reduce 5.8 Gt of water withdrawal, 127.1 Mtce of energy consumption, and 426.0 Mt of carbon emissions, each of which is equivalent to the corresponding annual EF of Belgium, Mexico, and Italy. These findings will urge China to extend the lifetime of existing and new buildings, in order to reduce the EF from further urbanization. This paper also verifies that the lifetime of a product or the replacement rate of a sector is a very important factor that influences the cumulative EF. When making policies to reduce the EF, adjusting people's behaviors to extend the lifetime of products or reduce the replacement rate of sectors may be a very simple and cost-effective option.


Assuntos
Dióxido de Carbono/análise , Meio Ambiente , Habitação , Bélgica , China , Conservação dos Recursos Naturais , Fontes Geradoras de Energia , Habitação/estatística & dados numéricos , Itália , México , Modelos Teóricos , Urbanização , Água
15.
Materials (Basel) ; 7(3): 2340-2355, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-28788570

RESUMO

A series of nickel-containing mesoporous silica samples (Ni-SiO2) with different nickel content (3.1%-13.2%) were synthesized by the evaporation-induced self-assembly method. Their catalytic activity was tested in carbon dioxide reforming of methane. The characterization results revealed that the catalysts, e.g., 6.7%Ni-SiO2, with highly dispersed small nickel particles, exhibited excellent catalytic activity and long-term stability. The metallic nickel particle size was significantly affected by the metal anchoring effect between metallic nickel particles and unreduced nickel ions in the silica matrix. A strong anchoring effect was suggested to account for the remaining of small Ni particle size and the improved catalytic performance.

16.
Environ Sci Technol ; 47(8): 3590-7, 2013 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-23461797

RESUMO

Drawing lessons from the clean development mechanism (CDM), this paper developed a combined margin methodology to quantify baseline emission factors of air pollutants in China's regional power grids. The simple average of baseline emission factors of SO2, NOX, and PM2.5 in China's six power grids in 2010 were respectively 1.91 kg/MWh, 1.83 kg/MWh and 0.32 kg/MWh. Several low-efficient mitigation technologies, such as low nitrogen oxide burner (LNB), were suggested to be replaced or used together with other technologies in order to virtually decrease the grid's emission factor. The synergies between GHG and air pollution mitigation in China's power sector was also notable. It is estimated that in 2010, that every 1% CO2 reduction in China's power generation sector resulted in the respective coreduction of 1.1%, 0.5%, and 0.8% of SO2, NOX, and PM2.5. Wind is the best technology to achieve the largest amount of coabatement in most parts of China. This methodology is recommended to be used in making comprehensive air pollution control strategies and in cobenefits analysis in future CDM approval processes.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Eletricidade , Dióxido de Carbono/análise , China , Geografia , Nitratos/análise , Nitritos/análise , Material Particulado/análise , Dióxido de Enxofre/análise
17.
Bioconjug Chem ; 23(4): 796-804, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22455451

RESUMO

Identification of endogenous angiogenesis inhibitors has led to development of an increasingly attractive strategy for cancer therapy and other angiogenesis-driven diseases. Vascular endothelial growth inhibitor (VEGI), a potent and relatively nontoxic endogenous angiogenesis inhibitor, has been intensively studied, and this work shed new light on developing promising anti-angiogenic strategies. It is well-documented that the RGD (Arg-Gly-Asp) motif exhibits high binding affinity to integrin α(v)ß(3), which is abundantly expressed in cancer cells and specifically associated with angiogenesis on tumors. Here, we designed a fusion protein containing the special RGD-4C motif sequence and VEGI-192, aimed at offering more effective multiple targeting to tumor cells and tumor vasculature, and higher anti-angiogenic and antitumor efficacy. Functional tests demonstrated that the purified recombinant human RGD-VEGI-192 protein (rhRGD-VEGI-192) potently inhibited endothelial growth in vitro and suppressed neovascularization in chicken chorioallantoic membrane in vivo, to a higher degree as compared with rhVEGI-192 protein. More importantly, rhRGD-VEGI-192, but not rhVEGI-192 protein, could potentially target MDA-MB-435 breast tumor cells, significantly inhibiting growth of MDA-MB-435 cells in vitro, triggered apoptosis in MDA-MB-435 cells by activation of caspase-8 as well as caspase-3, which was mediated by activating the JNK signaling associated with upregulation of pro-apoptotic protein Puma, and consequently led to the observed significant antitumor effect in vivo against a human breast cancer xenograft. Our study indicated that the RGD-VEGI-192 fusion protein might represent a novel anti-angiogenic and antitumor strategy.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/farmacologia , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais/efeitos dos fármacos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
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