We present the result of an experimental search for a heavy neutrino admixture in the electron capture process.The 95%confidence level upper limits from 0.02 to 0.04 are set for the mixing strength of heavy neutrinos ...We present the result of an experimental search for a heavy neutrino admixture in the electron capture process.The 95%confidence level upper limits from 0.02 to 0.04 are set for the mixing strength of heavy neutrinos in the neutrino mass range of 30keV to 90keV.展开更多
β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less of...β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less often.In the present study,we investigated the interaction and toxicity of Aβ1-42 and copper in the Aβ1-42 transgenic Caenorhabditis elegans worm model CL2006.Our data show that the paralysis behavior of CL2006 worms significantly deteriorated after exposure to 10-3 mol L-1 copper ions.However,the paralysis behavior was dramatically attenuated with exposure to 10-4 mol L-1 copper ions.The exogenous copper treatment also partially changed the homeostatic balance of zinc,manganese,and iron.Our data suggest that the accumulation of reactive oxygen species (ROS) was responsible for the paralysis induced by Aβ and copper in CL2006.The ROS generation induced by Aβ and copper appear to be through sod-1,prdx-2,skn-1,hsp-60 and hsp-16.2 genes.展开更多
The FY-3 satellite is a second-generation Chinese polar-orbit meteorological satellite.The Solar Backscatter Ultraviolet Sounder (SBUS),one of the main payloads on the FY-3 satellite,is the first Chinese ozone-monitor...The FY-3 satellite is a second-generation Chinese polar-orbit meteorological satellite.The Solar Backscatter Ultraviolet Sounder (SBUS),one of the main payloads on the FY-3 satellite,is the first Chinese ozone-monitoring instrument on a meteorological satellite.As part of the in-orbit validation of FY-3,we carried out a retrieval trial using measurements from SBUS during the period of 17-30 July,2008,and compared those data with measurements and retrieved profiles from the National Oceanic and Atmospheric Administration (NOAA) satellite SBUV/2.The results show that the precision of the measurements and retrieved profiles are quite good.The averaged relative difference percentages of the ozone profiles retrieved from SBUS and those from SBUV/2 are within ±7%.展开更多
The purpose of this study was to investigate compositional changes in human enamel irradiated with the free electron laser (FEL). The exposure on dental enamel at the wavelength of 9.64 μm was observed with the Beiji...The purpose of this study was to investigate compositional changes in human enamel irradiated with the free electron laser (FEL). The exposure on dental enamel at the wavelength of 9.64 μm was observed with the Beijing free electron laser. The distribution of elements in the irradiated or non-irradiated enamel was measured by scanning electron microscope (SEM) with energy-dispersive spectroscopy and synchrotron radiation X-ray fluorescence (SRXRF) in Beijing Synchrotron Radiation Facility (BSRF). The results showed that the P/Ca ratio in the ablation region of enamel at the maximum wavelength of infrared absorption was obviously smaller than that at the non-maximum wavelength. In the ablation region the ratios of P/Ca and Ca/Sr were smaller than those in the non-ablation region. The distributions of P, Ca and Sr in the ablation region were heterogeneous due to the element change caused by FEL irradiation.展开更多
文摘We present the result of an experimental search for a heavy neutrino admixture in the electron capture process.The 95%confidence level upper limits from 0.02 to 0.04 are set for the mixing strength of heavy neutrinos in the neutrino mass range of 30keV to 90keV.
基金supported by the National Natural Science Foundation of China (Grant No. 30870578)the National Basic Research Program of China (Grant No. 2006CB500700)funded by the US National Institutes of Health for providing nematode strains used in this work
文摘β-amyloid (Aβ) and copper play important roles in the pathogenesis of Alzheimer’s disease (AD).However,the behavioral correlativity and molecular mechanisms of Aβ and copper toxicity have been investigated less often.In the present study,we investigated the interaction and toxicity of Aβ1-42 and copper in the Aβ1-42 transgenic Caenorhabditis elegans worm model CL2006.Our data show that the paralysis behavior of CL2006 worms significantly deteriorated after exposure to 10-3 mol L-1 copper ions.However,the paralysis behavior was dramatically attenuated with exposure to 10-4 mol L-1 copper ions.The exogenous copper treatment also partially changed the homeostatic balance of zinc,manganese,and iron.Our data suggest that the accumulation of reactive oxygen species (ROS) was responsible for the paralysis induced by Aβ and copper in CL2006.The ROS generation induced by Aβ and copper appear to be through sod-1,prdx-2,skn-1,hsp-60 and hsp-16.2 genes.
基金supported by the National Natural Science Foundation of China (Grant No.40775024)National Basic Research Program of China (Grant No.2005CB422202)the 2nd ESA-MOST "Drag-Star" Program (Grant No.5253)
文摘The FY-3 satellite is a second-generation Chinese polar-orbit meteorological satellite.The Solar Backscatter Ultraviolet Sounder (SBUS),one of the main payloads on the FY-3 satellite,is the first Chinese ozone-monitoring instrument on a meteorological satellite.As part of the in-orbit validation of FY-3,we carried out a retrieval trial using measurements from SBUS during the period of 17-30 July,2008,and compared those data with measurements and retrieved profiles from the National Oceanic and Atmospheric Administration (NOAA) satellite SBUV/2.The results show that the precision of the measurements and retrieved profiles are quite good.The averaged relative difference percentages of the ozone profiles retrieved from SBUS and those from SBUV/2 are within ±7%.
基金This work was jointly supported by the National High Technology Laser Technology Field Foundation (Grant No. 863-410) the National Natural Science Foundation of China (Grant No. 19975055).
文摘The purpose of this study was to investigate compositional changes in human enamel irradiated with the free electron laser (FEL). The exposure on dental enamel at the wavelength of 9.64 μm was observed with the Beijing free electron laser. The distribution of elements in the irradiated or non-irradiated enamel was measured by scanning electron microscope (SEM) with energy-dispersive spectroscopy and synchrotron radiation X-ray fluorescence (SRXRF) in Beijing Synchrotron Radiation Facility (BSRF). The results showed that the P/Ca ratio in the ablation region of enamel at the maximum wavelength of infrared absorption was obviously smaller than that at the non-maximum wavelength. In the ablation region the ratios of P/Ca and Ca/Sr were smaller than those in the non-ablation region. The distributions of P, Ca and Sr in the ablation region were heterogeneous due to the element change caused by FEL irradiation.
