Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(6): 1082-1088, 2022 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-36575076

RESUMO

Epilepsy is a neurological disease with disordered brain network connectivity. It is important to analyze the brain network mechanism of epileptic seizure from the perspective of directed functional connectivity. In this paper, causal brain networks were constructed for different sub-bands of epileptic electroencephalogram (EEG) signals in interictal, preictal and ictal phases by directional transfer function method, and the information transmission pathway and dynamic change process of brain network under different conditions were analyzed. Finally, the dynamic changes of characteristic attributes of brain networks with different rhythms were analyzed. The results show that the topology of brain network changes from stochastic network to rule network during the three stage and the node connections of the whole brain network show a trend of gradual decline. The number of pathway connections between internal nodes of frontal, temporal and occipital regions increase. There are a lot of hub nodes with information outflow in the lesion region. The global efficiency in ictal stage of α, ß and γ waves are significantly higher than in the interictal and the preictal stage. The clustering coefficients in preictal stage are higher than in the ictal stage and the clustering coefficients in ictal stage are higher than in the interictal stage. The clustering coefficients of frontal, temporal and parietal lobes are significantly increased. The results of this study indicate that the topological structure and characteristic properties of epileptic causal brain network can reflect the dynamic process of epileptic seizures. In the future, this study has important research value in the localization of epileptic focus and prediction of epileptic seizure.


Assuntos
Epilepsia , Humanos , Encéfalo , Convulsões , Eletroencefalografia , Lobo Occipital
2.
Environ Sci Technol ; 56(22): 16082-16093, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36321829

RESUMO

Although widely recognized as the key to climate goals, coal "phase down" has long been argued for its side effects on energy security and social development. Retrofitting coal power units with biomass and coal co-firing with a carbon capture and storage approach provides an alternative way to avoid these side effects and make deep carbon dioxide emission cuts or even achieve negative emission. However, there is a lack of clear answers to how much the maximum emission reduction potential this approach can unlock, which is the key information to promote this technology on a large scale. Here, we focus on helping China's 4536 coal power units make differentiated retrofit choices based on unit-level heterogeneity information and resource spatial matching results. We found that China's coal power units have the potential to achieve 0.4 Gt of negative CO2 emission in 2025, and the cumulative negative CO2 emission would reach 10.32 Gt by 2060. To achieve negative CO2 emission, the biomass resource amount should be 1.65 times the existing agricultural and forestry residues, and the biomass and coal co-firing ratio should exceed 70%. Coal power units should grasp their time window; otherwise, the maximum negative potential would decrease at a rate of 0.35 Gt per year.


Assuntos
Dióxido de Carbono , Carvão Mineral , Dióxido de Carbono/análise , Biomassa , Clima , Tecnologia , China , Centrais Elétricas
3.
Proc Natl Acad Sci U S A ; 119(18): e2105006119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35467985

RESUMO

The world has committed trillions in fiscal expenditures to reboot the economy in the post­COVID-19 era. However, the effectiveness and the equity impacts of current fiscal stimuli are not fully understood. Using an extended adaptive regional input­output model, we assess the short-term impacts (2020 through 2022) of feasible stimuli on the global economy and the labor market. Our findings show that the stimuli pledged by 26 countries, i.e., 2.4 trillion euros in total, are effective in keeping the recession short and shallow by saving 53 million to 57 million jobs (compared to the no-stimulus scenario). However, the stimuli exacerbate income inequity at the global scale if we define "equity" as those who suffer more from the pandemic should receive more assistance. Low-skilled workers in these countries, who suffer more from the pandemic than high-skilled workers, benefit 38 to 41% less from the job-creation effects of the current fiscal stimuli. As an alternative, low-carbon stimuli can achieve a balance between effectiveness and equity at the global level. Low-carbon stimuli save 55 million to 58 million jobs and decrease income inequality by 2 to 3% globally compared to the currently pledged stimuli. Country-level situations are more complicated, as modifying the current stimuli to achieve more "greenness" brings win­win in effectiveness and equity in some countries, while in the others, more greenness and equity are at the expense of less job savings. Our findings underscore the need to consider the overlooked trade-offs between effectiveness, equity, and greenness, both globally and nationally, when designing further postpandemic fiscal stimuli.


Assuntos
Emprego , Renda , Mudança Climática , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...