Objective:To analysis effectiveness of the "14 plus 7 day quarantine" and "nucleic acid plus total antibody testing" strategy (combined screening strategy) for screenin the imported patients with COVID-19 in Xiamen.Methods:The study populations were overseas travelers arriving in Xiamen from March 17 to December 31, 2020, and overseas travelers who had quarantine outside Xiamen for less than 21 days from July 18 to December 31, 2020. Data were collected and analyzed on the timing of detection, pathways, and test results of the imported patients with COVID-19 after implementing combined screening strategy.Results:A total of 304 imported patients with COVID-19 were found from 174 628 overseas travelers and 943 overseas travelers from other cities. A total of 163 cases (53.6%) were diagnosed by multitime, multisite intensive nucleic acid testing after positive finding in total antibody testing. Among them, 27 (8.9%) were first positive for nucleic acid in 14 plus 7 day quarantine and 136 were first positive for nucleic acid in 14-day quarantine. Only 8 of these individuals were tested positive for nucleic acid after positive total antibody testing. The other 128 individuals were tested positive for nucleic acid after being negative for average 2.3 times (maximum of 6 times). Aditional 155 cases might be detected by using the combined "14 plus 7 day quarantine" and " nucleic acid plus total antibody testing" strategy compared with "14-day quarantine and nucleic acid testing" strategy, accounting for 51.0% of the total inbound infections. So the combined screening strategy doubled the detection rate for imported patients with COVID-19. No second-generation case caused by overseas travelers had been reported in Xiamen as of February 26, 2021.Conclusions:Xiamen's combined screening strategy can effectively screen the imported patients with COVID-19 who were first positive for nucleic acid after 14 day quarantine. Compared with "14 day quarantine and nucleic acid testing", the combined screening strategy improved detection rate and further reduced the risk of the secondary transmission caused by the imported patients with COVID-19.

Objective To reduce flight accidents and ensure aviation safety by comparing the combination effects of three attitude directional indicator (ADI ) designs and two reference frames [moving horizon (MH) and moving aircraft (MA)] on the operation of aircraft unusual attitude recovery. Methods The simulated recovery experiments were carried out by E-prime programming the interactively matched pictures that were presented by the regular perspective-view aircraft symbol (PAS) under unusual flight altitude and two reference frames that referenced MH and MA.The subjects were 34 male college students in the full-time military academy ,with average age of (22.43 ± 1.32) years old.The experiment was done based on 2×3×4 intra-test design.The combination of 2 reference frames and 3 ADI styles produced six displays and each of them corresponded to 8 rotation altitudes.Totally 48 pictures were displayed.During learning phase , the usual or unusual flight altitude pictures were presented to the subjects and the recovery operation was instructed to press the＂F＂key for the recovery to the left and the ＂J＂ key to the right.During training phase ,4 unusual flight altitude pictures were presented to the subjects.When the subjects were able to correctly judge these 4 pictures they were thought to be ready for the formal experiment.In formal experiment ,48 pictures were randomly presented to the subjects and the reaction time and the number of correct recovery were recorded. Results The intra-group variance analysis with reaction time as the dependent variable indicated that the effect of the interaction between ADI style and reference frame on subjects′reaction time was statistically significant ,[F(2 ,66)＝6.267 , P＝0.003 ,η2 ＝0.160].The combination of conventional ADI format and PAS format with MA reference frame showed better matched effect.The intra-group analysis of the variance with correct rate as the dependent variable indicated that the effect of interaction between the ADI style and the reference frame on subjects′correct rate was statistically significant [F(2 ,66)＝ 12.018 , P ＜ 0.001 ,η2 ＝ 0.267].The MH reference frame matched with 3 ADI formats showed better results than the CMD-MA display and the CON-MA display.PAS-MA design also showed good performance. Conclusions ① Two new ADI formats (CMD ,PAS) show certain advantages that traditional and conventional ADI format (CON) does not have.②The M H reference frame has the advantage on overall correct recovery rate.③The study theoretically recommends the PAS-MA display design.

Objective To reduce flight accidents and ensure aviation safety by comparing the combination effects of three attitude directional indicator (ADI ) designs and two reference frames [moving horizon (MH) and moving aircraft (MA)] on the operation of aircraft unusual attitude recovery. Methods The simulated recovery experiments were carried out by E-prime programming the interactively matched pictures that were presented by the regular perspective-view aircraft symbol (PAS) under unusual flight altitude and two reference frames that referenced MH and MA.The subjects were 34 male college students in the full-time military academy ,with average age of (22.43 ± 1.32) years old.The experiment was done based on 2×3×4 intra-test design.The combination of 2 reference frames and 3 ADI styles produced six displays and each of them corresponded to 8 rotation altitudes.Totally 48 pictures were displayed.During learning phase , the usual or unusual flight altitude pictures were presented to the subjects and the recovery operation was instructed to press the＂F＂key for the recovery to the left and the ＂J＂ key to the right.During training phase ,4 unusual flight altitude pictures were presented to the subjects.When the subjects were able to correctly judge these 4 pictures they were thought to be ready for the formal experiment.In formal experiment ,48 pictures were randomly presented to the subjects and the reaction time and the number of correct recovery were recorded. Results The intra-group variance analysis with reaction time as the dependent variable indicated that the effect of the interaction between ADI style and reference frame on subjects′reaction time was statistically significant ,[F(2 ,66)＝6.267 , P＝0.003 ,η2 ＝0.160].The combination of conventional ADI format and PAS format with MA reference frame showed better matched effect.The intra-group analysis of the variance with correct rate as the dependent variable indicated that the effect of interaction between the ADI style and the reference frame on subjects′correct rate was statistically significant [F(2 ,66)＝ 12.018 , P ＜ 0.001 ,η2 ＝ 0.267].The MH reference frame matched with 3 ADI formats showed better results than the CMD-MA display and the CON-MA display.PAS-MA design also showed good performance. Conclusions ① Two new ADI formats (CMD ,PAS) show certain advantages that traditional and conventional ADI format (CON) does not have.②The M H reference frame has the advantage on overall correct recovery rate.③The study theoretically recommends the PAS-MA display design.

Objective To investigate the mechanism of motor recovery in hemiplegic patients after ischemic stroke using acupuncture-induced blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) and diffusion tensor imaging (DTI).Methods A total of 20 patients with left hemiplegia after ischemic stroke were enrolled in the study. DTI raw data was used to reconstruct three dimensional image of pyramidal tract through post-processing of workstation,and the damage and recovery of the pyramidal tract were observed. SPM8 and other software were used to compare and analyze the acupuncture-induced BOLD-fMRI data, and the distribution differences in the brain activation areas were compared. Results The muscle strength grade and the Fugl-Meyer scale score at 6 months were significantly higher than those during 3-6 weeks after stroke onset. DTI showed that the right pyramidal tract had different degrees of damage, interrupt, compression, and displacement during 3-6 weeks after onset, and there were different degrees of repair, remodeling at 6 months after onset. Acupuncture-induced BOLD-fMRI showed that compared with 3-6 weeks after onset, the positive activated brain regions were mainly located in the motor related brain regions in bilateral frontal cortex and the left cerebellum, and the negative activated brain regions were mainly located in the limbic system, such as bilateral anterior cingulate cortex and parahippocampal gyrus. Conclusions The mechanism of motor recovery in hemiplegic patients after ischemic stroke may be mainly related to the regulation and compensation of motor related brain regions,as well as the regulation of muscular tension through the extrapyramidal system. The repair and reorganization of the damaged motor pathway may also be the mechanism of motor recovery in hemiplegic patients after ischemic stroke.

Objective To obtain the 3D shape data and features of 50th percentile posterior neck length in Chinese pilots.Methods The posterior neck length was measured in 150 fighter pilots by developed probe array and then 32 fighter pilots who were in accordance with 50th percentile posterior neck length were selected based on these 3D digitized posterior neck measurements.Results The method of digitized measurement was established.The range of posterior neck length was from 81 mm to 168 mm,the mean length was 127.3 mm in 150 pilots.In 32 fighter pilots with 50th percentile posterior neck length,the length range was from 120 mm to 123 mm,the mean length was 121.4 mm.The least square fitting curve was got then and 3D model was established.Conclusions The developed equipment and method are practical and effective.The results can be applied to the 3D analysis of posterior neck shape features and to the design of the neck support and head rest of ejection seat.

Objective To obtain the 3D shape data and features of 50th percentile posterior neck length in Chinese pilots.Methods The posterior neck length was measured in 150 fighter pilots by developed probe array and then 32 fighter pilots who were in accordance with 50th percentile posterior neck length were selected based on these 3D digitized posterior neck measurements.Results The method of digitized measurement was established.The range of posterior neck length was from 81 mm to 168 mm,the mean length was 127.3 mm in 150 pilots.In 32 fighter pilots with 50th percentile posterior neck length,the length range was from 120 mm to 123 mm,the mean length was 121.4 mm.The least square fitting curve was got then and 3D model was established.Conclusions The developed equipment and method are practical and effective.The results can be applied to the 3D analysis of posterior neck shape features and to the design of the neck support and head rest of ejection seat.

The purpose of the present study was to investigate Norovirus infection status among patients with virus diarrhea in Xiamen city and provide evidence for exploring the prevalence characteristics and constituting appropriate control strategy.From April 2007 to July 2008,323 fecal samples of virus diarrhea cases collected from 3 surveillance hospitals in Xiamen were detected for antigen and RNA by ELISA and Real-Time RT-PCR respectively.The RdPd genes from some samples were furtherly amplified and sequenced for genogroup identification when the Real-Time RT-PCR detection results were positive.In the 323 fecal specimens,68 (21.05%) were positive for Norovirus antigen by ELISA and 107 (31.13%) were positive for Norovirus RNA by Real-Time RT-PCR.The overall positive prevalence rate of Norovirus in Xiamen was 38.08%.107 positive specimens were detected by Real-Time RT-PCR and results showed that 80 strains were Norovirus GGⅡ(74.77%),2 strains were GGⅠ(1.87%) and 25 strains (23.36%)were unidentified.It's indicated that Norovirus infection in Xiamen district was mainly caused by Norovirus GGⅡ,and Norovirus was also the main cause for virus diarrhea.