The computational fluid dynamics (CFD) method is used to investigate the aerodynamic characteristics of the seat/occupant with windblast protection devices. The upwind Osher scheme is used for the spatial discretisa...The computational fluid dynamics (CFD) method is used to investigate the aerodynamic characteristics of the seat/occupant with windblast protection devices. The upwind Osher scheme is used for the spatial discretisation. The detached-eddy simulation (DES) based on the Spalart-Allmaras one-equation turbulence model is ap- plied to the detached viscous flow simulation behind the seat/occupant, with Mach numbers 0.6 and 1.2 at attack angles between --10 and 30°, and at two sideslip angles of 0 and 15°, respectively. The aerodynamic characteristics of seat/occupants with and without windblast protection devices are calculated in cases of the freestream Mach numbers 0. 8 and 1.6, attack angles from 5 to 30°, and three sideslip angles of 0, --20 and --50°, respectively. Results show that simulation results agree well with experimental data. And the occupant is efficiently protected by windblast protection devices.展开更多
AIM:The evidence for an association between Helicobacter pylori (H pylori) and gastroesophageal reflux disease,either in non-erosive (NERD) or erosive esophagitis (ERD) remains uncertain.The available data on the hist...AIM:The evidence for an association between Helicobacter pylori (H pylori) and gastroesophageal reflux disease,either in non-erosive (NERD) or erosive esophagitis (ERD) remains uncertain.The available data on the histological changes in NERD and the effect on Hpyloriinfection on them are elusive. The aim of this study therefore was to prospectively evaluate the histological findings and the impact of Hpyloriinfection on a group of symptomatic patients with NERD. METHODS:Fifty consecutive patients were prospectively evaluated for symptoms compatible with GORD.In all cases, routine endoscopy and lugol directed biopsies were performed and assessed histologically in a blinded manner. RESULTS:The overall prevalence of Hpyloriinfection was 70%.Twenty-nine patients out of 50 (58%) were NERD patients.No statistical significance was observed between the H pyloristatus and NERD.The remaining 21 (42%) were diagnosed as follows:13 (26%),6 (12%),2(4%) with esophagitis grade A,B and C respectively.A statistically significant correlation was observed between the Hpylori+ and esophagitis grade A,as well as between Hpylori-and grade B.Biopsies from 2 patients were not included because of insufficient materials.Histologically,a basal zone hyperplasia was found in 47 (97.91%) patients,alterations of glycogen content in 47 (97.91%),papillae elongation in 33 (68.75%), blood vessels dilatation in 35(72.91%),chronic inflammation in 21 (43.75%),infiltration with eosinophils,neutophils and T-lymphocytes in 4 (8.33%),6 (12.5%) and 39 (81.25%) respectively.No correlation was observed between the Hpyloristatus and the histological parameters studied either in NERD or GERD. CONCLUSION:Histological assessment can not differentiate symptomatic patients with erosive versus non-erosive reflux disease.Moreover,Hpyloriinfection may not act as an important factor in patients with NERD.展开更多
基金Supported by the Aeronautical Science Foundation of China(2008ZC52039)~~
文摘The computational fluid dynamics (CFD) method is used to investigate the aerodynamic characteristics of the seat/occupant with windblast protection devices. The upwind Osher scheme is used for the spatial discretisation. The detached-eddy simulation (DES) based on the Spalart-Allmaras one-equation turbulence model is ap- plied to the detached viscous flow simulation behind the seat/occupant, with Mach numbers 0.6 and 1.2 at attack angles between --10 and 30°, and at two sideslip angles of 0 and 15°, respectively. The aerodynamic characteristics of seat/occupants with and without windblast protection devices are calculated in cases of the freestream Mach numbers 0. 8 and 1.6, attack angles from 5 to 30°, and three sideslip angles of 0, --20 and --50°, respectively. Results show that simulation results agree well with experimental data. And the occupant is efficiently protected by windblast protection devices.
文摘AIM:The evidence for an association between Helicobacter pylori (H pylori) and gastroesophageal reflux disease,either in non-erosive (NERD) or erosive esophagitis (ERD) remains uncertain.The available data on the histological changes in NERD and the effect on Hpyloriinfection on them are elusive. The aim of this study therefore was to prospectively evaluate the histological findings and the impact of Hpyloriinfection on a group of symptomatic patients with NERD. METHODS:Fifty consecutive patients were prospectively evaluated for symptoms compatible with GORD.In all cases, routine endoscopy and lugol directed biopsies were performed and assessed histologically in a blinded manner. RESULTS:The overall prevalence of Hpyloriinfection was 70%.Twenty-nine patients out of 50 (58%) were NERD patients.No statistical significance was observed between the H pyloristatus and NERD.The remaining 21 (42%) were diagnosed as follows:13 (26%),6 (12%),2(4%) with esophagitis grade A,B and C respectively.A statistically significant correlation was observed between the Hpylori+ and esophagitis grade A,as well as between Hpylori-and grade B.Biopsies from 2 patients were not included because of insufficient materials.Histologically,a basal zone hyperplasia was found in 47 (97.91%) patients,alterations of glycogen content in 47 (97.91%),papillae elongation in 33 (68.75%), blood vessels dilatation in 35(72.91%),chronic inflammation in 21 (43.75%),infiltration with eosinophils,neutophils and T-lymphocytes in 4 (8.33%),6 (12.5%) and 39 (81.25%) respectively.No correlation was observed between the Hpyloristatus and the histological parameters studied either in NERD or GERD. CONCLUSION:Histological assessment can not differentiate symptomatic patients with erosive versus non-erosive reflux disease.Moreover,Hpyloriinfection may not act as an important factor in patients with NERD.