Many diseases can produce cardiac overload, of these disease hypertension, valve disease congenital anomaly in addition to many other disease. One of the most common diseases causing left ventricle overload is hypertension. A long term hypertension can cause myocardium hypertrophy leading to changes in the cardiac contractility and reduced efficiency. The investigations were carried out using conventional echocardiography techniques in addition to the tissue Doppler imaging (TDI) from which many noninvasive measurements can be readily obtained. The study has involved the effect of hypertension on the myocardium stiffness index through the measurement of early diastolic filling (E) and the early velocity of lateral mitral annulus (Ea) from which left ventricle filling pressure can be obtained. Our aim was to investigate the changes in the myocardium index of diastolic stiffness using TDI for patients suffering from systemic hypertension. We studied 263 hypertensive patients (105 males and 158 females of average age of 54.07± 12.7) and 166 healthy subjects (age range 40.06± 12.8,53 males and 113 females) as a control group. Measurements were carried out using tissue Doppler imaging (TDI) of the mitral annulus in addition to other echocardiographic measurements for the assessment of left ventricle end diastolic dimension (LVEDD), Doppler peak early (E) and late (A) diastolic filling velocities. Results reveal that mitral annular early diastolic velocity (Ea) measured by TDI, that (Ea) was significantly lower for the hypertensive group in comparison with the control group (Ea 9.81 ± 2.87 cm/s for hypertensive vs. 12.90 ± 2.395 cm/s for control p value <0.001. Hypertensive group also showed a significantly higher mitral annular late diastolic velocity (Aa) in comparison with control group as Aa 11.21 ± 2.504 cm/s for hypertensive vs. 9.787 ±2.201cm/s for control, p value <0.001.. In conclusion, LV myocardial diastolic stiffness index is increased in hypertensive patients.
The insulation system of a machine coil includes several layers made of materials with different characteristics. The effective insulation design of machine coils, especially in the machine end winding, depends upon an accurate model of the stress grading system. This paper proposes a modeling approach to predict the transient overvoltage, electric field, and heat generation in machine coils with a stress grading system, considering the variation of physical properties in the insulation layers. A non-uniform line model is used to divide the coil in different segments based on material properties and lengths: overhang, stress grading and slot. The cascaded connection of chain matrices is used to connect segments for the representation of the
... Show MoreThis paper presents the non-linear finite element method to study the behavior of four reinforced rectangular concrete MD beams with web circular openings tested under two-point load. The numerical finite elements methods have been used in a much more practical way to achieve approximate solutions for more complex problems. The ABAQUS /CAE is chosen to explore the behavior of MD beams. This paper also studies, the effect of both size and shape of the circular apertures of MD beams. The strengthening technique that used in this paper is externally strengthening using CFRP around the opening in the MD beams. The numerical results were compared to the experimental results in terms of ultimate load failure and displace
... Show MoreSpatial data analysis is performed in order to remove the skewness, a measure of the asymmetry of the probablitiy distribution. It also improve the normality, a key concept of statistics from the concept of normal distribution “bell shape”, of the properties like improving the normality porosity, permeability and saturation which can be are visualized by using histograms. Three steps of spatial analysis are involved here; exploratory data analysis, variogram analysis and finally distributing the properties by using geostatistical algorithms for the properties. Mishrif Formation (unit MB1) in Nasiriya Oil Field was chosen to analyze and model the data for the first eight wells. The field is an anticline structure with northwest- south
... Show MoreThe control of prostheses and their complexities is one of the greatest challenges limiting wide amputees’ use of upper limb prostheses. The main challenges include the difficulty of extracting signals for controlling the prostheses, limited number of degrees of freedom (DoF), and cost-prohibitive for complex controlling systems. In this study, a real-time hybrid control system, based on electromyography (EMG) and voice commands (VC) is designed to render the prosthesis more dexterous with the ability to accomplish amputee’s daily activities proficiently. The voice and EMG systems were combined in three proposed hybrid strategies, each strategy had different number of movements depending on the combination protocol between voic
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