We investigate the short-time decoherence of a solid-state qubit under Ohmic noise at optimal operation points. The decoherence is analyzed by maximum norm of the deviation density operator. It is shown that at the te...We investigate the short-time decoherence of a solid-state qubit under Ohmic noise at optimal operation points. The decoherence is analyzed by maximum norm of the deviation density operator. It is shown that at the temperature T = 3 mK, the loss of the fidelity due to decoherence is much smaller than the DiVincenzo low decoherence criterion, which means that the mode/may be an optimal candidate of qubit for quantum computation.展开更多
This paper presents an analysis of the fire trends in southern European countries, where forest fires are a major hazard. Data on number of fires and burned area size from 1985 until 2009 were retrieved from the Europ...This paper presents an analysis of the fire trends in southern European countries, where forest fires are a major hazard. Data on number of fires and burned area size from 1985 until 2009 were retrieved from the European Fire Database in the European Forest Fire Information System and used to study the temporal and spatial variability of fire occurrence at three different spatial scales： the whole European Mediterranean region, country level and province level （NUTS3）. The temporal trends were assessed with the Mann-Kendall test and Sen＇s slope in the period 1985-2009. At regional （supranational） level, our results suggest a significant decreasing trend in the burned area for the whole study period. At country level, the trends vary by country, although there is a general increase in number of fires, mainly in Portugal, and a decrease in bumed areas, as is the case of Spain. A similar behavior was found at NUTS3 level, with an increase of number of fires in the Spanish and Portuguese provinces and a generalized decrease of the burned area in most provinces of the region. These results provide an important insight into the spatial distribution and temporal evolution of fires, a crucial step to investigate the underlying causes and impacts of fire occurrence in this region.展开更多
Mancozeb is a multi-site fungicide used to control late blight （Phytophthora infestans） and early blight （Alternaria solani） in potatoes, and is currently due for re-approval as part of the EU Sustainable Use Dire...Mancozeb is a multi-site fungicide used to control late blight （Phytophthora infestans） and early blight （Alternaria solani） in potatoes, and is currently due for re-approval as part of the EU Sustainable Use Directive---Authorisation of Plant Protection Products Regulation （EC） No 1107/2009. In order to understand its value to the EU potato industry, a stakeholder survey was conducted to understand the implications for P. infestans control and the impact on EU potato production if mancozeb was not available. In total, 319 growers and advisers were surveyed in 8 countries： France, Germany, Ireland, Netherlands, Greece, Italy, Spain and the UK, to determine how they use mancozeb, potential alternative control strategies and the implications of withdrawal. This study demonstrates that mancozeb is a widely used and cost-effective multisite active ingredient, which is a highly valued means of control for P. infestans. Based on the survey results, a loss of mancozeb would lead to a reduction in gross margin for potato producers in these countries of 787 million to 507 million depending on the level of P. infestans pressure. The combined impact of high cost of production and increased risks is likely to lead to reductions in the availability of EU potatoes and increased costs to consumers. In addition, an assessment was completed to determine the impact of mancozeb withdrawal on fungicide resistance development to single-site acting fungicides, finding that the loss of a multi-site active ingredient like mancozeb would severely compromise fungicide resistance management.展开更多
We give estimates of the remainder terms for several conformally-invariant Sobolev-type inequalities on the Heisenberg group. By considering the variations of associated functionals, we give a stability for two dual i...We give estimates of the remainder terms for several conformally-invariant Sobolev-type inequalities on the Heisenberg group. By considering the variations of associated functionals, we give a stability for two dual inequalities: The fractional Sobolev(FS) and Hardy-Littlewood-Sobolev(HLS) inequalities, in terms of distance to the submanifold of extremizers. Then we compare their remainder terms to improve the inequalities in another way. We also compare, in the limit case, the remainder terms of Beckner-Onofri(BO) inequality and its dual logarithmic Hardy-Littlewood-Sobolev(Log-HLS) inequality. Besides, we also list without proof some results for other groups of Iwasawa-type. Our results generalize earlier works on Euclidean spaces of Chen et al.(2013) and Dolbeault and Jankowiak(2014) onto some groups of Heisenberg-type. We worked for "almost"all fractions especially for comparing results, and the stability of HLS is also absolutely new, even for Euclidean case.展开更多
文摘We investigate the short-time decoherence of a solid-state qubit under Ohmic noise at optimal operation points. The decoherence is analyzed by maximum norm of the deviation density operator. It is shown that at the temperature T = 3 mK, the loss of the fidelity due to decoherence is much smaller than the DiVincenzo low decoherence criterion, which means that the mode/may be an optimal candidate of qubit for quantum computation.
文摘This paper presents an analysis of the fire trends in southern European countries, where forest fires are a major hazard. Data on number of fires and burned area size from 1985 until 2009 were retrieved from the European Fire Database in the European Forest Fire Information System and used to study the temporal and spatial variability of fire occurrence at three different spatial scales： the whole European Mediterranean region, country level and province level （NUTS3）. The temporal trends were assessed with the Mann-Kendall test and Sen＇s slope in the period 1985-2009. At regional （supranational） level, our results suggest a significant decreasing trend in the burned area for the whole study period. At country level, the trends vary by country, although there is a general increase in number of fires, mainly in Portugal, and a decrease in bumed areas, as is the case of Spain. A similar behavior was found at NUTS3 level, with an increase of number of fires in the Spanish and Portuguese provinces and a generalized decrease of the burned area in most provinces of the region. These results provide an important insight into the spatial distribution and temporal evolution of fires, a crucial step to investigate the underlying causes and impacts of fire occurrence in this region.
文摘Mancozeb is a multi-site fungicide used to control late blight （Phytophthora infestans） and early blight （Alternaria solani） in potatoes, and is currently due for re-approval as part of the EU Sustainable Use Directive---Authorisation of Plant Protection Products Regulation （EC） No 1107/2009. In order to understand its value to the EU potato industry, a stakeholder survey was conducted to understand the implications for P. infestans control and the impact on EU potato production if mancozeb was not available. In total, 319 growers and advisers were surveyed in 8 countries： France, Germany, Ireland, Netherlands, Greece, Italy, Spain and the UK, to determine how they use mancozeb, potential alternative control strategies and the implications of withdrawal. This study demonstrates that mancozeb is a widely used and cost-effective multisite active ingredient, which is a highly valued means of control for P. infestans. Based on the survey results, a loss of mancozeb would lead to a reduction in gross margin for potato producers in these countries of 787 million to 507 million depending on the level of P. infestans pressure. The combined impact of high cost of production and increased risks is likely to lead to reductions in the availability of EU potatoes and increased costs to consumers. In addition, an assessment was completed to determine the impact of mancozeb withdrawal on fungicide resistance development to single-site acting fungicides, finding that the loss of a multi-site active ingredient like mancozeb would severely compromise fungicide resistance management.
基金supported by National Natural Science Foundation of China(Grant No.11371036)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.2012000110059)China Scholarship Council(Grant No.201306010009)
文摘We give estimates of the remainder terms for several conformally-invariant Sobolev-type inequalities on the Heisenberg group. By considering the variations of associated functionals, we give a stability for two dual inequalities: The fractional Sobolev(FS) and Hardy-Littlewood-Sobolev(HLS) inequalities, in terms of distance to the submanifold of extremizers. Then we compare their remainder terms to improve the inequalities in another way. We also compare, in the limit case, the remainder terms of Beckner-Onofri(BO) inequality and its dual logarithmic Hardy-Littlewood-Sobolev(Log-HLS) inequality. Besides, we also list without proof some results for other groups of Iwasawa-type. Our results generalize earlier works on Euclidean spaces of Chen et al.(2013) and Dolbeault and Jankowiak(2014) onto some groups of Heisenberg-type. We worked for "almost"all fractions especially for comparing results, and the stability of HLS is also absolutely new, even for Euclidean case.
