The dengue virus （DENV） is a vital global public health issue. The 2014 dengue epidemic in Guangzhou, China, caused approximately 40,000 cases of infection and five deaths. We carried out a comprehensive investigati...The dengue virus （DENV） is a vital global public health issue. The 2014 dengue epidemic in Guangzhou, China, caused approximately 40,000 cases of infection and five deaths. We carried out a comprehensive investigation aimed at identifying the transmission sources in this dengue epidemic. To analyze the phylogenetics of the 2014 dengue strains, the envelope （E） gene sequences from 17 viral strains isolated from 168 dengue patient serum samples were sequenced and a phylogenetic tree was reconstructed. All 17 strains were serotype I strains, including 8 genotype I and 9 genotype V strains. Additionally, 6 genotype I strains that were probably introduced to China from Thailand before 2009 were widely transmitted in the 2013 and 2014 epidemics, and they continued to circulate until 2015, with one affinis strain being found in Singapore. The other 2 genotype I strains were introduced from the Malaya Peninsula in 2014. The transmission source of the 9 genotype V strains was from Malaysia in 2014. DENVs of different serotypes and genotypes co-circulated in the 2014 dengue outbreak in Guangzhou. Moreover, not only had DENV been imported to Guangzhou, but it had also been gradually exported, as the viruses exhibited an enzootic transmission cycle in Guangzhou.展开更多
Intramedullary schwannoma of the upper cervical spinal cord is rarely reported in forensic medicine.We herein report a case involving a patient who died of compression from an intramedullary schwannoma in the upper ce...Intramedullary schwannoma of the upper cervical spinal cord is rarely reported in forensic medicine.We herein report a case involving a patient who died of compression from an intramedullary schwannoma in the upper cervical spinal cord.A 30-year-old man initially presented with a five-day history of pain in the left chest that progressed to weakening in the left arm.Although the patient was treated with analgesic poultices,he developed inspiratory dyspnoea and died while working the next day without having undergone any medical imaging examination or surgical treatment.Anatomical and histopathological examinations revealed an intramedullary schwannoma in the left cervical spinal cord(C_(3)-C_(5))underneath the spinal nerve root.The cause of death might have been asphyxia secondary to the tumour,which interfered with the nerve function in the respiratory muscles.This finding suggests that an autopsy is essential for pathologists and medicolegists to comprehensively undertake their due obligation to obtain“the first evidence”,especially when there is a lack of directly related evidence.As part of the central nervous system,the spinal cord could be systematically included in a routine pathological autopsy in some cases.展开更多
YSZ:Eu powder was prepared by sol spray pyrolysis method.Thermal barrier coatings(TBCs)composed of Eu^(3+)-doped pure tetragonal yttrium-stabilized zirconia(namely,YSZ:Eu)were fabricated by air-plasma spraying techniq...YSZ:Eu powder was prepared by sol spray pyrolysis method.Thermal barrier coatings(TBCs)composed of Eu^(3+)-doped pure tetragonal yttrium-stabilized zirconia(namely,YSZ:Eu)were fabricated by air-plasma spraying technique.Crystal structure and fluorescence intensity of YSZ:Eu coating were investigated after aging at 1200℃for 5-100 h.X-ray diffraction(XRD)indicates that tetragonal phase in YSZ:Eu coating had high resistance to degradation over a wide range of time periods and temperatures.Luminescence results indicate that asymmetry ratios of the fluorescence emission spectra were stable in a range of 1.2±0.2.Relationships between phase structure and lattice distortion were further studied by fluorescence spectroscopy measurement using I_(606)/I_(590)intensity ratio.The fluorescence results were consistent with those drawn by XRD,where the high stability of YSZ:Eu coating was confirmed.Excellent thermal stability,in terms of both the phase structure and luminescence intensity,of YSZ:Eu coating indicates that the present preparation method is suitable for phosphor powder applications.展开更多
基金supported by the Guangdong Natural Science Foundation (No. S2012030006598)the Science & Technology Planning Project of Guangdong Province of China (No. 2013A020229007)the Innovative Program of the State Key Laboratory of Virology (No. 2016KF001)
文摘The dengue virus （DENV） is a vital global public health issue. The 2014 dengue epidemic in Guangzhou, China, caused approximately 40,000 cases of infection and five deaths. We carried out a comprehensive investigation aimed at identifying the transmission sources in this dengue epidemic. To analyze the phylogenetics of the 2014 dengue strains, the envelope （E） gene sequences from 17 viral strains isolated from 168 dengue patient serum samples were sequenced and a phylogenetic tree was reconstructed. All 17 strains were serotype I strains, including 8 genotype I and 9 genotype V strains. Additionally, 6 genotype I strains that were probably introduced to China from Thailand before 2009 were widely transmitted in the 2013 and 2014 epidemics, and they continued to circulate until 2015, with one affinis strain being found in Singapore. The other 2 genotype I strains were introduced from the Malaya Peninsula in 2014. The transmission source of the 9 genotype V strains was from Malaysia in 2014. DENVs of different serotypes and genotypes co-circulated in the 2014 dengue outbreak in Guangzhou. Moreover, not only had DENV been imported to Guangzhou, but it had also been gradually exported, as the viruses exhibited an enzootic transmission cycle in Guangzhou.
文摘Intramedullary schwannoma of the upper cervical spinal cord is rarely reported in forensic medicine.We herein report a case involving a patient who died of compression from an intramedullary schwannoma in the upper cervical spinal cord.A 30-year-old man initially presented with a five-day history of pain in the left chest that progressed to weakening in the left arm.Although the patient was treated with analgesic poultices,he developed inspiratory dyspnoea and died while working the next day without having undergone any medical imaging examination or surgical treatment.Anatomical and histopathological examinations revealed an intramedullary schwannoma in the left cervical spinal cord(C_(3)-C_(5))underneath the spinal nerve root.The cause of death might have been asphyxia secondary to the tumour,which interfered with the nerve function in the respiratory muscles.This finding suggests that an autopsy is essential for pathologists and medicolegists to comprehensively undertake their due obligation to obtain“the first evidence”,especially when there is a lack of directly related evidence.As part of the central nervous system,the spinal cord could be systematically included in a routine pathological autopsy in some cases.
基金financially supported by the Project of Defense Industrial Technology Development Program(No.JCKY2020404B001)the Science Center for Gas Turbine Project(No.P2021-A-IV-002-001)
文摘YSZ:Eu powder was prepared by sol spray pyrolysis method.Thermal barrier coatings(TBCs)composed of Eu^(3+)-doped pure tetragonal yttrium-stabilized zirconia(namely,YSZ:Eu)were fabricated by air-plasma spraying technique.Crystal structure and fluorescence intensity of YSZ:Eu coating were investigated after aging at 1200℃for 5-100 h.X-ray diffraction(XRD)indicates that tetragonal phase in YSZ:Eu coating had high resistance to degradation over a wide range of time periods and temperatures.Luminescence results indicate that asymmetry ratios of the fluorescence emission spectra were stable in a range of 1.2±0.2.Relationships between phase structure and lattice distortion were further studied by fluorescence spectroscopy measurement using I_(606)/I_(590)intensity ratio.The fluorescence results were consistent with those drawn by XRD,where the high stability of YSZ:Eu coating was confirmed.Excellent thermal stability,in terms of both the phase structure and luminescence intensity,of YSZ:Eu coating indicates that the present preparation method is suitable for phosphor powder applications.
