This study investigates the impact of economic policy uncertainty(EPU)on the volatility of European Union(EU)carbon futures prices and whether it has predictive power for the volatility of carbon futures prices.The GA...This study investigates the impact of economic policy uncertainty(EPU)on the volatility of European Union(EU)carbon futures prices and whether it has predictive power for the volatility of carbon futures prices.The GARCH-MIDAS model is applied for evaluating the impact of different EPU indexes on the price volatility of European Union Allowance(EUA)futures.We then compare the predictive power for the volatility of the two GARCH-MIDAS models based on different EPU indexes and six GARCH-type models.Our empirical results show that the GARCH-MIDAS models,which exhibit superior out-of-sample predictive ability,outperform GARCH-type models.The results also indicate that EPU has noticeable effect on the volatility of EUA futures.Specifically,the forecast accuracy of the EU EPU index is significantly higher than that of the global EPU index.Robustness checks further confirm that the EPU index(especially the EPU index of the EU)has strong predictive power for EUA futures prices.Additionally,using the volatility forecasting methods that GARCH-MIDAS models combine with the EPU index,investors can construct their portfolios to realize economic returns.展开更多
While repurposed drugs came in handy earlier in the wake of the coronavirus disease 2019(COVID-19)pandemic,vaccination has been considered a more sustainable approach.The recent spikes have been linked to“double,”“...While repurposed drugs came in handy earlier in the wake of the coronavirus disease 2019(COVID-19)pandemic,vaccination has been considered a more sustainable approach.The recent spikes have been linked to“double,”“triple,”and even multi-mutant variants,thus renewing calls for deeper structural and functional insights of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)as a lead to rationale design of therapeutics,vaccines,and point-of-care diagnostics.There is a repertoire of findings from the earliest SARS-CoV-2 molecular mimicry to evade host immunity cum host immune responses to the role of the viral glycocalyx in modulating the susceptibility and severity of infection through attraction and repulsive interactions.Recently,molecular studies of some viral components that aid infection in the face of vaccination seem unending.In addition,the wave of infections and the attendant case fatality ratios have necessitated the need for emergency use authorizations for COVID-19 vaccines and in vitro diagnostics.This review provides key updates of SARS-CoV-2,current antigenic and formulation strategies,with emergency use authorizations considerations for future vaccine candidates and diagnostics.We also premise that despite the difficulty in modeling and analyzing glycans,understanding and exploiting their roles in the SARS-CoV-2 architecture is fundamental to glycan-based COVID-19 vaccines devoid of inconsistent clinical outcomes.展开更多
基金supported by the National Natural Science Foundation of China(Nos.71871030,72131011)the Open Fund Project of Key Research Institute of Philosophies and Social Sciences in Hunan University of China(No.20FEFMZ1).
文摘This study investigates the impact of economic policy uncertainty(EPU)on the volatility of European Union(EU)carbon futures prices and whether it has predictive power for the volatility of carbon futures prices.The GARCH-MIDAS model is applied for evaluating the impact of different EPU indexes on the price volatility of European Union Allowance(EUA)futures.We then compare the predictive power for the volatility of the two GARCH-MIDAS models based on different EPU indexes and six GARCH-type models.Our empirical results show that the GARCH-MIDAS models,which exhibit superior out-of-sample predictive ability,outperform GARCH-type models.The results also indicate that EPU has noticeable effect on the volatility of EUA futures.Specifically,the forecast accuracy of the EU EPU index is significantly higher than that of the global EPU index.Robustness checks further confirm that the EPU index(especially the EPU index of the EU)has strong predictive power for EUA futures prices.Additionally,using the volatility forecasting methods that GARCH-MIDAS models combine with the EPU index,investors can construct their portfolios to realize economic returns.
文摘While repurposed drugs came in handy earlier in the wake of the coronavirus disease 2019(COVID-19)pandemic,vaccination has been considered a more sustainable approach.The recent spikes have been linked to“double,”“triple,”and even multi-mutant variants,thus renewing calls for deeper structural and functional insights of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)as a lead to rationale design of therapeutics,vaccines,and point-of-care diagnostics.There is a repertoire of findings from the earliest SARS-CoV-2 molecular mimicry to evade host immunity cum host immune responses to the role of the viral glycocalyx in modulating the susceptibility and severity of infection through attraction and repulsive interactions.Recently,molecular studies of some viral components that aid infection in the face of vaccination seem unending.In addition,the wave of infections and the attendant case fatality ratios have necessitated the need for emergency use authorizations for COVID-19 vaccines and in vitro diagnostics.This review provides key updates of SARS-CoV-2,current antigenic and formulation strategies,with emergency use authorizations considerations for future vaccine candidates and diagnostics.We also premise that despite the difficulty in modeling and analyzing glycans,understanding and exploiting their roles in the SARS-CoV-2 architecture is fundamental to glycan-based COVID-19 vaccines devoid of inconsistent clinical outcomes.
