Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading. The elastic response of the vessel may become larger in a later stage compared to its response during the initial stag...Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading. The elastic response of the vessel may become larger in a later stage compared to its response during the initial stage. The dynamic responses of infinitely long cylindrical containment vessels subjected to uniformly-distributed internal blast loading are studied using LS-DYNA. The development of bending modes and the interaction between the breathing mode and bending modes are observed. The methodology developed for dynamic elastic buckling analysis is employed to study the strain growth phenomenon in explosion containment vessels. It is shown that the dynamic instable vibration of a containment vessel is the basic mechanism of strain growth.展开更多
Backround N-terminal pro-brain natriuretic peptide （NT-proBNP） is a reliable predictor in acute coronary artery disease （CAD）. Little is known about patients with stable CAD, especially Chinese patients with CAD. ...Backround N-terminal pro-brain natriuretic peptide （NT-proBNP） is a reliable predictor in acute coronary artery disease （CAD）. Little is known about patients with stable CAD, especially Chinese patients with CAD. The aim of the present study was to investigate the association of NT-proBNP levels with the severity of CAD in patients with normal left ventricular ejection fraction. Methods A total of 658 consecutive patients were divided into two groups based on angiograms： CAD group （n=484） and angiographic normal control group （n=174）. The severity of CAD was evaluated by modified Gensini score, and its relationship with NT-proBNP was analyzed. Results The prevalence of risk factors such as age, male gender, diabetes mellitus （DM）, dyslipidemia, smoking, and family history of CAD in the CAD group were higher than that in the control group. In multivariate regression model analysis, age, gender, and DM were determinants of the presence of CAD. NT-pro BNP was found to be an independent predictor for CAD （OR：1.66 （95% CI： 1.06-2.61）, P 〈0.05）. In a receiver operating characteristic （ROC）curve analysis, an NT-proBNP value of 641.15 pmol/L was identified as a cut-off value in the diagnosis or exclusion of CAD （area under curve （AUC）=0.56, 95% CI： 0.51-0.61）. Furthermore, NT-proBNP was positively correlated with Gensini score （r=0.14, P 〈0.001） in patients with CAD. Conclusion NT-proBNP was an independent predictor for Chinese patients with CAD, suggesting that the NT-proBNP level might be associated with the presence and the severity of CAD.展开更多
文摘Strain growth is a phenomenon observed in containment vessels subjected to internal blast loading. The elastic response of the vessel may become larger in a later stage compared to its response during the initial stage. The dynamic responses of infinitely long cylindrical containment vessels subjected to uniformly-distributed internal blast loading are studied using LS-DYNA. The development of bending modes and the interaction between the breathing mode and bending modes are observed. The methodology developed for dynamic elastic buckling analysis is employed to study the strain growth phenomenon in explosion containment vessels. It is shown that the dynamic instable vibration of a containment vessel is the basic mechanism of strain growth.
基金Wu Naqiong and Ma Fenglian contributed equally to this study. This work is partly supported by grants from National Natural Scientific Foundation of China （No. 81070171 and No. 81241121）, Specialized Research Fund for the Doctoral Program of Higher Education of China （No. 20111106110013）, Capital Special Foundation of Clinical Application Research （No. Z121107001012015）, Capital Health Development Fund （No. 2011400302）, and Beijing Natural Science Foundation （No. 7131014） No conflict of interest needs to be declared.
文摘Backround N-terminal pro-brain natriuretic peptide （NT-proBNP） is a reliable predictor in acute coronary artery disease （CAD）. Little is known about patients with stable CAD, especially Chinese patients with CAD. The aim of the present study was to investigate the association of NT-proBNP levels with the severity of CAD in patients with normal left ventricular ejection fraction. Methods A total of 658 consecutive patients were divided into two groups based on angiograms： CAD group （n=484） and angiographic normal control group （n=174）. The severity of CAD was evaluated by modified Gensini score, and its relationship with NT-proBNP was analyzed. Results The prevalence of risk factors such as age, male gender, diabetes mellitus （DM）, dyslipidemia, smoking, and family history of CAD in the CAD group were higher than that in the control group. In multivariate regression model analysis, age, gender, and DM were determinants of the presence of CAD. NT-pro BNP was found to be an independent predictor for CAD （OR：1.66 （95% CI： 1.06-2.61）, P 〈0.05）. In a receiver operating characteristic （ROC）curve analysis, an NT-proBNP value of 641.15 pmol/L was identified as a cut-off value in the diagnosis or exclusion of CAD （area under curve （AUC）=0.56, 95% CI： 0.51-0.61）. Furthermore, NT-proBNP was positively correlated with Gensini score （r=0.14, P 〈0.001） in patients with CAD. Conclusion NT-proBNP was an independent predictor for Chinese patients with CAD, suggesting that the NT-proBNP level might be associated with the presence and the severity of CAD.
