For open sea conditions the sea surface roughness is described as a function of surface stress and wind speed over sea surface by Charnock relation. The sea surface roughnessn in the North-west Pacific Ocean is derive...For open sea conditions the sea surface roughness is described as a function of surface stress and wind speed over sea surface by Charnock relation. The sea surface roughnessn in the North-west Pacific Ocean is derived successfully using wind speed data estimated by the TOPEX satellite altimeter. From the results we find that： （1） the mean sea surface roughness in winter is greater than in summer; （2） compared with other sea areas, the sea surface roughness in the sea area east of Japan （ N30°- 40°, E135°- 150°） is larger than in other sea areas; （3） sea surface roughness in the South China Sea changes more greatly than that in the Bohai Sea, Yellow Sea and East China Sea.展开更多
Objective: There have been no prospective studies in Spain focused on stroke r ecurrence. The purpose of this work is toestimate the risk of stroke recurrence and mortality in the community of Bajo Arag′on, Spain and...Objective: There have been no prospective studies in Spain focused on stroke r ecurrence. The purpose of this work is toestimate the risk of stroke recurrence and mortality in the community of Bajo Arag′on, Spain and to compare it with pr evious studies conducted in other countries. Methods: A cohort of 425 patients w ith first ever stroke was followed up for a mean period of 4 years (range: 20- 78 months). The mean age was 75.4 years. The survival function for recurrence an d mortality was analysed by means of the actuarial method. Survival comparisons were made for the different vascular risk factors with the Kaplan Meier method. The risk of recurrence and death was adjusted for relevant variables with the C ox proportional hazards model. We also made a separate analysis by stroke subtyp es. Results: At the end of the follow up we found an overall mortality of 38%( 163/425) with 69 patients dying in hospital, and an overall recurrence rate of 1 7.6%(63/356) . The cumulative risk of recurrence was 2.1%at 30 days, 9.5%at 1 year and 26%at 5 years. The cumulative risk of mortality was 16%at 30 days, 30%at 1 year and 48%at 5 years. Only age (Hazard Ratio: 1.05, 95%CI: 1.02-1. 08) and the addition of risk factors (Hazard Ratio: 1.32, 95%CI: 1.12-1.57) we re significant predictors of recurrence. In general, none of the risk factors in dividually predicted stroke recurrence. The highest risk of recurrence was obser ved in large vessel atherothrombotic infarction followed by cardioembolic infar ction. In cardioembolic stroke, the association of atrial fibrillation plus eith er valvular disease or congestive heart failure significantly predicted recurren ce of the same type (Relative Risk: 3.1; 95%CI: 2.2-4.4). Conclusion: The risk of early stroke recurrence in our area was lower than those observed in most st udies, so was the risk of long term mortality. However, the risk of long term recurrence was similar. Age was the main predictor of death and recurrence. The patients with atrial fibrillation plus another heart disease are at increased ri sk of recurrent cardioembolic stroke.展开更多
文摘For open sea conditions the sea surface roughness is described as a function of surface stress and wind speed over sea surface by Charnock relation. The sea surface roughnessn in the North-west Pacific Ocean is derived successfully using wind speed data estimated by the TOPEX satellite altimeter. From the results we find that： （1） the mean sea surface roughness in winter is greater than in summer; （2） compared with other sea areas, the sea surface roughness in the sea area east of Japan （ N30°- 40°, E135°- 150°） is larger than in other sea areas; （3） sea surface roughness in the South China Sea changes more greatly than that in the Bohai Sea, Yellow Sea and East China Sea.
文摘Objective: There have been no prospective studies in Spain focused on stroke r ecurrence. The purpose of this work is toestimate the risk of stroke recurrence and mortality in the community of Bajo Arag′on, Spain and to compare it with pr evious studies conducted in other countries. Methods: A cohort of 425 patients w ith first ever stroke was followed up for a mean period of 4 years (range: 20- 78 months). The mean age was 75.4 years. The survival function for recurrence an d mortality was analysed by means of the actuarial method. Survival comparisons were made for the different vascular risk factors with the Kaplan Meier method. The risk of recurrence and death was adjusted for relevant variables with the C ox proportional hazards model. We also made a separate analysis by stroke subtyp es. Results: At the end of the follow up we found an overall mortality of 38%( 163/425) with 69 patients dying in hospital, and an overall recurrence rate of 1 7.6%(63/356) . The cumulative risk of recurrence was 2.1%at 30 days, 9.5%at 1 year and 26%at 5 years. The cumulative risk of mortality was 16%at 30 days, 30%at 1 year and 48%at 5 years. Only age (Hazard Ratio: 1.05, 95%CI: 1.02-1. 08) and the addition of risk factors (Hazard Ratio: 1.32, 95%CI: 1.12-1.57) we re significant predictors of recurrence. In general, none of the risk factors in dividually predicted stroke recurrence. The highest risk of recurrence was obser ved in large vessel atherothrombotic infarction followed by cardioembolic infar ction. In cardioembolic stroke, the association of atrial fibrillation plus eith er valvular disease or congestive heart failure significantly predicted recurren ce of the same type (Relative Risk: 3.1; 95%CI: 2.2-4.4). Conclusion: The risk of early stroke recurrence in our area was lower than those observed in most st udies, so was the risk of long term mortality. However, the risk of long term recurrence was similar. Age was the main predictor of death and recurrence. The patients with atrial fibrillation plus another heart disease are at increased ri sk of recurrent cardioembolic stroke.
