The accuracy and repeatability of computer aided cervical vertebra landmarking (CACVL) were investigated in cephalogram. 120 adolescents (60 boys, 60 girls) aged from 9.1 to 17.2 years old were randomly selected. Twenty-seven landmarks from the second to fifth cervical vertebrae on the lateral cephalogram were identified. In this study, the system of CACVL was developed and used to identify and calculate the landmarks by fast marching method and parabolic curve fitting. The accuracy and repeatability in CACVL group were compared with those in two manual landmarking groups [orthodontic experts (OE) group and orthodontic novices (ON) group]. The results showed that, as for the accuracy, there was no significant difference between CACVL group and OE group no matter in x-axis or y-axis (P>0.05), but there was significant difference between CACVL group and ON group, as well as OE group and ON group in both axes (P<0.05). As for the repeatability, CACVL group was more reliable than OE group and ON group in both axes. It is concluded that CACVL has the same or higher accuracy, better repeatability and less workload than manual landmarking methods. It's reliable for cervical parameters identification on the lateral cephalogram and cervical vertebral maturation prediction in orthodontic practice and research.

The accuracy and repeatability of computer aided cervical vertebra landmarking (CACVL) were investigated in cephalogram.120 adolescents (60 boys,60 girls) aged from 9.1 to 17.2 years old were randomly selected.Twenty-seven landmarks from the second to fifth cervical vertebrae on the lateral cephalogram.were identified.In this study,the system of CACVL was developed and used to identify and calculate the landmarks by fast marching method and parabolic curve fitting.The accuracy and repeatability in CACVL group were compared with those in two manual landmarking groups [orthodontic experts (OE) group and orthodontic novices (ON) group].The results showed that,as for the accu racy,there was no significant difference between CACVL group and OE group no matter in x-axis or y-axis (P＞0.05),but there was significant difference between CACVL group and ON group,as well as OE group and ON group in both axes (P＜0.05).As for the repeatability,CACVL group was more reliable than OE group and ON group in both axes.It is concluded that CACVL has the same or higher accuracy,better repeatability and less workload than manual landmarking methods.It's reliable for cervical parameters identification on the lateral cephalogram and cervical vertebral maturation prediction in orthodontic practice and research.

Objective:To investigate the epidemiological and clinical characteristics of a case infected with avian influenza A (H5N6) virus associated with exposure to aerosol and provide evidence for the prevention and control of human infection with avian influenza virus.Methods:Epidemiological investigation was conducted to identify the history of exposure, infection route, and disease progression. Real-time fluorescent quantitative RT-PCR was used to test the samples collected from the case, close contacts, environment and poultry market.Results:The case had no history of exposure to live poultry and poultry market. But before the onset the case had a history of exposure to the live poultry placed in a car with doors and windows closed. The samples collected from the case’s lower respiratory tract and the remaining frozen chicken meat were all influenza A (H5N6) virus positive.Conclusions:The source of infection was the live poultry, and the infection route might be the exposure to aerosol in a car with doors and windows closed, where the poultry were temporarily stored. It is necessary to promote centralized poultry slaughtering, cold chain distribution and fresh poultry sale, as well as strengthen health education and establish the concept of consuming fresh poultry.

Objective To analyze the evaluation indicators of pre-hospital first aid for adult patients with acute severe trauma to provide the evidence-based basis for the initiation of "zero channel" in first aid work.Methods The literatures such as expert consensus,clinical research,guideline and systematic review were retrieved from PubMed,Medline,Embase,Cochrane Central Register of Controlled Trials,and China Knowledge Network by computer.The retrieval time was from January 2013 to November 2023.After screen-ing the literatures according to the standard,the quality evaluation and evidence grading were conducted by a-dopting different tools.Results A total of 8 literatures were included,including 4 clinical studies,2 expert consensus and 2 systematic reviews.Finally,10 evidence-based evidences for the initiation of "zero channel" in adult patients with acute severe trauma were summarized.Conclusion This study summarizes the relevant in-dicators of "zero channel" initiation in the adult patients with acute severe trauma,which is helpful for clinical medical staff to start the first aid "zero channel" in time and increase the success rate of rescue.