A comprehensive energy-saving sail (CES) has been proposed in order to promote energy saving and emission reduction from shipping. Wind energy is harvested for propulsion and electrical generator at the same time by a...A comprehensive energy-saving sail (CES) has been proposed in order to promote energy saving and emission reduction from shipping. Wind energy is harvested for propulsion and electrical generator at the same time by a unique structure of CES. A CFD (Computational Fluid Dynamics) code is verified by a case of arc wind sail, and it is used to simulate the pressure and velocity around the CES. The results show that the outlet velocity of air tunnel V<sub>o</sub> and wind velocity V<sub>i</sub> serve as an equation V<sub>o</sub> ≈ 1.31V<sub>i</sub>, which means the CES can effectively improve the conversion efficiency. In addition, it is found that V<sub>o</sub> increases with the tunnel diameter to some extend over which it will keep almost constant.展开更多
Background:Red-cell transfusion is critical for surgery during the peri-operative period;however,the transfusion threshold remains controversial mainly owing to the diversity among patients.The patient’s medical stat...Background:Red-cell transfusion is critical for surgery during the peri-operative period;however,the transfusion threshold remains controversial mainly owing to the diversity among patients.The patient’s medical status should be evaluated before making a transfusion decision.Herein,we developed an individualized transfusion strategy using the West-China-Liu’s Score based on the physiology of oxygen delivery/consumption balance and designed an open-label,multicenter,randomized clinical trial to verify whether it reduced red cell requirement as compared with that associated with restrictive and liberal strategies safely and effectively,providing valid evidence for peri-operative transfusion.Methods:Patients aged>14 years undergoing elective non-cardiac surgery with estimated blood loss>1000 mL or 20%blood volume and hemoglobin concentration<10 g/dL were randomly assigned to an individualized strategy,a restrictive strategy following China’s guideline or a liberal strategy with a transfusion threshold of hemoglobin concentration<9.5 g/dL.We evaluated two primary outcomes:the proportion of patients who received red blood cells(superiority test)and a composite of in-hospital complications and all-cause mortality by day 30(non-inferiority test).Results:We enrolled 1182 patients:379,419,and 384 received individualized,restrictive,and liberal strategies,respectively.Approximately 30.6%(116/379)of patients in the individualized strategy received a red-cell transfusion,less than 62.5%(262/419)in the restrictive strategy(absolute risk difference,31.92%;97.5%confidence interval[CI]:24.42-39.42%;odds ratio,3.78%;97.5%CI:2.70-5.30%;P<0.001),and 89.8%(345/384)in the liberal strategy(absolute risk difference,59.24%;97.5%CI:52.91-65.57%;odds ratio,20.06;97.5%CI:12.74-31.57;P<0.001).No statistically significant differences were found in the composite of in-hospital complications and mortality by day 30 among the three strategies.Conclusion:The individualized red-cell transfusion strategy using the West-China-Liu’s Score reduced red-cell transfusion without increasing in-hospital complications and mortality by day 30 when compared with restrictive and liberal strategies in elective non-cardiac surgeries.Trial registration:ClinicalTrials.gov,NCT01597232.展开更多
文摘A comprehensive energy-saving sail (CES) has been proposed in order to promote energy saving and emission reduction from shipping. Wind energy is harvested for propulsion and electrical generator at the same time by a unique structure of CES. A CFD (Computational Fluid Dynamics) code is verified by a case of arc wind sail, and it is used to simulate the pressure and velocity around the CES. The results show that the outlet velocity of air tunnel V<sub>o</sub> and wind velocity V<sub>i</sub> serve as an equation V<sub>o</sub> ≈ 1.31V<sub>i</sub>, which means the CES can effectively improve the conversion efficiency. In addition, it is found that V<sub>o</sub> increases with the tunnel diameter to some extend over which it will keep almost constant.
基金supported by grants from the National Key Research and Development Program of China(No.2018YFC2001800)the 1-3-5 Project for disciplines of excellence,West China Hospital,and Sichuan University Education Foundation.
文摘Background:Red-cell transfusion is critical for surgery during the peri-operative period;however,the transfusion threshold remains controversial mainly owing to the diversity among patients.The patient’s medical status should be evaluated before making a transfusion decision.Herein,we developed an individualized transfusion strategy using the West-China-Liu’s Score based on the physiology of oxygen delivery/consumption balance and designed an open-label,multicenter,randomized clinical trial to verify whether it reduced red cell requirement as compared with that associated with restrictive and liberal strategies safely and effectively,providing valid evidence for peri-operative transfusion.Methods:Patients aged>14 years undergoing elective non-cardiac surgery with estimated blood loss>1000 mL or 20%blood volume and hemoglobin concentration<10 g/dL were randomly assigned to an individualized strategy,a restrictive strategy following China’s guideline or a liberal strategy with a transfusion threshold of hemoglobin concentration<9.5 g/dL.We evaluated two primary outcomes:the proportion of patients who received red blood cells(superiority test)and a composite of in-hospital complications and all-cause mortality by day 30(non-inferiority test).Results:We enrolled 1182 patients:379,419,and 384 received individualized,restrictive,and liberal strategies,respectively.Approximately 30.6%(116/379)of patients in the individualized strategy received a red-cell transfusion,less than 62.5%(262/419)in the restrictive strategy(absolute risk difference,31.92%;97.5%confidence interval[CI]:24.42-39.42%;odds ratio,3.78%;97.5%CI:2.70-5.30%;P<0.001),and 89.8%(345/384)in the liberal strategy(absolute risk difference,59.24%;97.5%CI:52.91-65.57%;odds ratio,20.06;97.5%CI:12.74-31.57;P<0.001).No statistically significant differences were found in the composite of in-hospital complications and mortality by day 30 among the three strategies.Conclusion:The individualized red-cell transfusion strategy using the West-China-Liu’s Score reduced red-cell transfusion without increasing in-hospital complications and mortality by day 30 when compared with restrictive and liberal strategies in elective non-cardiac surgeries.Trial registration:ClinicalTrials.gov,NCT01597232.
