Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages an...Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India.展开更多
深松作业存在的主要问题是耕作阻力大。深松机中深松铲作为重要部件，其形状和结构参数直接影响着深松作业的牵引阻力及作业质量等。通过推拉力计测量了鸭掌形铲在不同入土深度时的耕作阻力；通过变换不同铲形的耕作试验，测量了现有凿...深松作业存在的主要问题是耕作阻力大。深松机中深松铲作为重要部件，其形状和结构参数直接影响着深松作业的牵引阻力及作业质量等。通过推拉力计测量了鸭掌形铲在不同入土深度时的耕作阻力；通过变换不同铲形的耕作试验，测量了现有凿形铲、鸭掌形铲、翼形铲在入土深度为35 cm时的耕作阻力。结果表明：牵引阻力随着鸭掌形铲入土深度的增大而增大，因为土壤硬度随着土层深度的增加而增大，所以在10～20 cm 的土层中对深松铲的阻力较小，深松铲在20～30 cm的土层中的阻力有较大增加，在30～40 cm 的土层中阻力增加幅度最大，其规律符合二次曲线。不同铲形耕作试验表明：铲形不同时，铲尖与土壤接触面积不同，导致深松铲与土壤之间的剪切力和挤压力不同，其牵引阻力与铲尖面积满足对数关系。展开更多
文摘Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India.
文摘深松作业存在的主要问题是耕作阻力大。深松机中深松铲作为重要部件，其形状和结构参数直接影响着深松作业的牵引阻力及作业质量等。通过推拉力计测量了鸭掌形铲在不同入土深度时的耕作阻力；通过变换不同铲形的耕作试验，测量了现有凿形铲、鸭掌形铲、翼形铲在入土深度为35 cm时的耕作阻力。结果表明：牵引阻力随着鸭掌形铲入土深度的增大而增大，因为土壤硬度随着土层深度的增加而增大，所以在10～20 cm 的土层中对深松铲的阻力较小，深松铲在20～30 cm的土层中的阻力有较大增加，在30～40 cm 的土层中阻力增加幅度最大，其规律符合二次曲线。不同铲形耕作试验表明：铲形不同时，铲尖与土壤接触面积不同，导致深松铲与土壤之间的剪切力和挤压力不同，其牵引阻力与铲尖面积满足对数关系。
