Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(...Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(AMI).Methods Two hundred and eight patients with AMI episoded within 12 hours, male 159, female 49, age 58.9 ±11.9 (34～88)years, were randomly divided into transradial artery access for primary PCI (TRA pPCI) group of 106 cases and transfemoral artery access for PCI (TFA pPCI) group of 102 cases during Sept, 2000 to Aug, 2002. The protocols of the manipulation duration and the effect for TRA pPCI and TFA pPCI procedures were respectively compared, including the time of transradial artery puncture and the rate of puncture success at first time ; the time of guiding catheter engaging into target coronary ostium; the rate of patence in infarct related artery (IRA); total duration of manipulation and the successful rate.The incidence of complications such as bleeding, vessel injury,thrombi and embolism as well as the average stay of hospitalization between two groups was compared. The status and the incidance of vessel spasm were observed and the effect of medicine administration to prevent from and relieve the vascular spasm was evaluated. The time of Allen’s test before and after TRA pPCI , the inner diameter and the peak of blood velocity of the right and left radial artery were investigated with color Doppler vessel echography as well as the complications of radial artery were followed up 1 month after TRA pPCI procedure. Results Two cases in every TRA pPCI and TFA pPCI groups were crossed over each other because procedure of the transradial or transfemoral access was failure. One handred and six vessels (48 vessels in LAD,22 vessels in LCX and 36 vessels in RCA) associated with 28 vessels of total occlusion in TRA pPCI group and 102 vessels (51 vessels in LAD,18 veesles in LCX and 33 vessels in RCA) with 24 vessels in total occlusion in TFA pPCI group were angioplasticized . The successful rates of the first time puncture in access artery, the re patence IRA and pPCI were similar in TRA pPCI and TFA pPCI groups ( 93.4% vs 96.1% ;100% vs 100%; 96.2% vs 97.1% , P >0.05 ). There were no significant diffierence in the average time of puncture time of access artery ,engaging in target vessels of guiding catheters and the total procedure of PCI between the two groups ( 1.3 ±0.3s vs 1.2 ±0.3s ; 6.0 ±1.6min vs 5.8 ±0.9min ; 49.2 ±24.1min vs 46.5 ± 26.4min , P >0.05 ). The access artery complications such as bleeding ,hematoma and embolism as well the veneous thrombosis in TFA pPCI group were much more than those in TRA pPCI group(p< 0.01 ). Although slight artery spasm of 4.7% cases in TRA pPCI group was happened during the procedure of PCI , the procedure had being continued after administration of medicine to release the spasm. The time of Allen’s test ,diameter and the systolic velocity of blood in daul radial arteries were no significant change before and after pPCI.Conclusions The duration and effect by TRA pPCI for AMI with stable hemodynamics was similar to TFA pPCI. The complications such as of bleeding,vessel injury, thrombi and embolism by TRA pPCI were few, and it was unnecessary to discontinue the anticoagulation medicine. TRA pPCI might be selected as a access vessel for pPCI in AMI patients with stable hemodynamics.展开更多
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com...Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE＇s theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE＇s theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.展开更多
Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate c...Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate changes. Three empirical orthogonal function(EOF) techniques are discussed and applied to decades of sea-ice concentration(SIC) dataset in Arctic area for identifying independent patterns. It was found that: 1) discrepancies exist in magnitude and scope for each EOF pattern, however, the first two leading EOFs of variability possess high similarities in structure and shape; 2) Even though there are somewhat differences in amplitude of each PC mode, the first two leading PC modes maintain consistent in overall trend and periodicity; 3) There are significant discrepancies and inconsistencies in the third and fourth leading EOF and PC modes. The accuracies of three techniques are further validated in representing the physical phenomena of SIC anomaly patterns.展开更多
文摘Objective Comparative study on the feasibility,safety and outcome of transradial artery and transfemoral artery access for primary percutaneous coronary intervention (PCI) in patients with acute myocardial infarction(AMI).Methods Two hundred and eight patients with AMI episoded within 12 hours, male 159, female 49, age 58.9 ±11.9 (34～88)years, were randomly divided into transradial artery access for primary PCI (TRA pPCI) group of 106 cases and transfemoral artery access for PCI (TFA pPCI) group of 102 cases during Sept, 2000 to Aug, 2002. The protocols of the manipulation duration and the effect for TRA pPCI and TFA pPCI procedures were respectively compared, including the time of transradial artery puncture and the rate of puncture success at first time ; the time of guiding catheter engaging into target coronary ostium; the rate of patence in infarct related artery (IRA); total duration of manipulation and the successful rate.The incidence of complications such as bleeding, vessel injury,thrombi and embolism as well as the average stay of hospitalization between two groups was compared. The status and the incidance of vessel spasm were observed and the effect of medicine administration to prevent from and relieve the vascular spasm was evaluated. The time of Allen’s test before and after TRA pPCI , the inner diameter and the peak of blood velocity of the right and left radial artery were investigated with color Doppler vessel echography as well as the complications of radial artery were followed up 1 month after TRA pPCI procedure. Results Two cases in every TRA pPCI and TFA pPCI groups were crossed over each other because procedure of the transradial or transfemoral access was failure. One handred and six vessels (48 vessels in LAD,22 vessels in LCX and 36 vessels in RCA) associated with 28 vessels of total occlusion in TRA pPCI group and 102 vessels (51 vessels in LAD,18 veesles in LCX and 33 vessels in RCA) with 24 vessels in total occlusion in TFA pPCI group were angioplasticized . The successful rates of the first time puncture in access artery, the re patence IRA and pPCI were similar in TRA pPCI and TFA pPCI groups ( 93.4% vs 96.1% ;100% vs 100%; 96.2% vs 97.1% , P >0.05 ). There were no significant diffierence in the average time of puncture time of access artery ,engaging in target vessels of guiding catheters and the total procedure of PCI between the two groups ( 1.3 ±0.3s vs 1.2 ±0.3s ; 6.0 ±1.6min vs 5.8 ±0.9min ; 49.2 ±24.1min vs 46.5 ± 26.4min , P >0.05 ). The access artery complications such as bleeding ,hematoma and embolism as well the veneous thrombosis in TFA pPCI group were much more than those in TRA pPCI group(p< 0.01 ). Although slight artery spasm of 4.7% cases in TRA pPCI group was happened during the procedure of PCI , the procedure had being continued after administration of medicine to release the spasm. The time of Allen’s test ,diameter and the systolic velocity of blood in daul radial arteries were no significant change before and after pPCI.Conclusions The duration and effect by TRA pPCI for AMI with stable hemodynamics was similar to TFA pPCI. The complications such as of bleeding,vessel injury, thrombi and embolism by TRA pPCI were few, and it was unnecessary to discontinue the anticoagulation medicine. TRA pPCI might be selected as a access vessel for pPCI in AMI patients with stable hemodynamics.
基金Project(RG086/10AET) supported by the Institute of Research Management and Monitoring,University of Malaya,Malaysia
文摘Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE＇s theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE＇s theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design.
基金Project(41301420)supported by the National Natural Science Foundation of ChinaProject(12JJB005)supported by the Hunan Provincial Natural Science Foundation of China+1 种基金Project(2014VGE03)supported by the Key Lab of Virtual Geographic Environment from Ministry of Education,ChinaProject(LEND2013B04)supported by the NASA Key Laboratory of Land Environment and Disaster Monitoring,USA
文摘Change in Arctic sea ice extent is one of the indicators of global climate changes. Spatio-temporal change and change patterns can be identified using various methods to facilitate human understanding global climate changes. Three empirical orthogonal function(EOF) techniques are discussed and applied to decades of sea-ice concentration(SIC) dataset in Arctic area for identifying independent patterns. It was found that: 1) discrepancies exist in magnitude and scope for each EOF pattern, however, the first two leading EOFs of variability possess high similarities in structure and shape; 2) Even though there are somewhat differences in amplitude of each PC mode, the first two leading PC modes maintain consistent in overall trend and periodicity; 3) There are significant discrepancies and inconsistencies in the third and fourth leading EOF and PC modes. The accuracies of three techniques are further validated in representing the physical phenomena of SIC anomaly patterns.
