In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by c...In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by considering different parameters,such as horizontal and vertical seismic acceleration coefficients,ratio of reinforcement length to wall height,back fill friction angle,foundation soil friction angle,soil reinforcement interface friction angle and surcharge.The parametric study shows that the seismic safety factor increases by 24-fold when the foundation soil friction angle varies from 25°to 45°,and increases by 2-fold when the soil reinforcement interface friction angle varies from 0 to 30°.That is to say,the bigger values the foundation soil and/or soil reinforcement interface friction angles have,the safer the reinforced soil walls become in the seismic design.The results were also compared with those obtained from pseudo-static method.It is found that there is a higher value of the safety factor by the present work.展开更多
Background Heart failure (HF) is an increasing problem for the aging population, specifically among women. The etiology of HF influences both the selection and outcome of the treatment. There are variations between ...Background Heart failure (HF) is an increasing problem for the aging population, specifically among women. The etiology of HF influences both the selection and outcome of the treatment. There are variations between genders in morbidity and mortality in different studies, possibly reflecting etiology. The objective of this study was to examine the strength of evidence available for gender differences in the etiology of chronic heart failure. Methods Computer-assisted searches from 1980-2009 for gender differences in the etiology of heart failure were performed (Medline, EMBASE and PubMed). From 2347 abstracts reviewed based on inclusion criteria, 35 original articles were chosen for review. Data extraction was based on observational studies (prospective/retrospective cohort or cross sectional) with a mean follow up of 3 months. There was no interrater variability between the 2 reviewers on data-extraction. Results Ventricular systolic dysfunction being more associated with male sex, but female sex was more reported to be associated with preserved left ventricular function. Ischemic etiology and associated coronary heart disease were strongly correlated with male sex. The risk for HF was dramatically more elevated for women with systolic hypertension but the association for diabetes mellitus as the etiology of HF was somewhat equal between males and females. Conclusions One of the limitations in reaching conclusions about gender differences in cardiovascular disease is that many major clinical trials do not include a gender analysis nor they are powered to do so as women are under-represented in most of the HF studies. The need remains for a well designed prospective study of sufficient numbers of male and female patients with and without heart failure and analyzing etiology and risk factors based on the sex differences.展开更多
文摘In order to evaluate the seismic stability of reinforced soil walls against bearing capacity failure,the seismic safety factor of reinforced soil walls was determined by using pseudo-dynamic method,and calculated by considering different parameters,such as horizontal and vertical seismic acceleration coefficients,ratio of reinforcement length to wall height,back fill friction angle,foundation soil friction angle,soil reinforcement interface friction angle and surcharge.The parametric study shows that the seismic safety factor increases by 24-fold when the foundation soil friction angle varies from 25°to 45°,and increases by 2-fold when the soil reinforcement interface friction angle varies from 0 to 30°.That is to say,the bigger values the foundation soil and/or soil reinforcement interface friction angles have,the safer the reinforced soil walls become in the seismic design.The results were also compared with those obtained from pseudo-static method.It is found that there is a higher value of the safety factor by the present work.
文摘Background Heart failure (HF) is an increasing problem for the aging population, specifically among women. The etiology of HF influences both the selection and outcome of the treatment. There are variations between genders in morbidity and mortality in different studies, possibly reflecting etiology. The objective of this study was to examine the strength of evidence available for gender differences in the etiology of chronic heart failure. Methods Computer-assisted searches from 1980-2009 for gender differences in the etiology of heart failure were performed (Medline, EMBASE and PubMed). From 2347 abstracts reviewed based on inclusion criteria, 35 original articles were chosen for review. Data extraction was based on observational studies (prospective/retrospective cohort or cross sectional) with a mean follow up of 3 months. There was no interrater variability between the 2 reviewers on data-extraction. Results Ventricular systolic dysfunction being more associated with male sex, but female sex was more reported to be associated with preserved left ventricular function. Ischemic etiology and associated coronary heart disease were strongly correlated with male sex. The risk for HF was dramatically more elevated for women with systolic hypertension but the association for diabetes mellitus as the etiology of HF was somewhat equal between males and females. Conclusions One of the limitations in reaching conclusions about gender differences in cardiovascular disease is that many major clinical trials do not include a gender analysis nor they are powered to do so as women are under-represented in most of the HF studies. The need remains for a well designed prospective study of sufficient numbers of male and female patients with and without heart failure and analyzing etiology and risk factors based on the sex differences.