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Uncorrected atrial septal defect undergoes right ventricle chronic volume overload which may lead to pulmonary hypertension and Eisenmenger Syndrome. The soluble suppression of tumorigenicity-2 is a left ventricle strain biomarker; however, its role in right ventricle strain is unclear. This study aimed to investigate the implication of serum soluble suppression of tumorigenicity-2 in adult uncorrected atrial septal defect. This was a cross-sectional study. We enrolled 81 adult uncorrected secundum atrial septal defect patients. Clinical and hemodynamic data were collected. Serum samples were withdrawn from the pulmonary artery during right heart catheterization. Serum soluble suppression of tumorigenicity-2 and NT-proBNP levels were measured. Subjects were divided into three groups based on clinical and hemodynamic severity. The correlation of soluble suppression of tumorigenicity-2 with patients' data and comparison among groups were analyzed. A pvalue <0.05 was considered statistically significant. Results showed that, there were significant correlations between serum soluble suppression of tumorigenicity-2 and mean pulmonary artery pressure (r= 0.203, p= 0.035) and right ventricle end-diastolic diameter (r= 0.203, p<0.05). Median serum soluble suppression of tumorigenicity-2 level was incrementally increased from group I (atrial septal defect and no-pulmonary hypertension), group II (left-to-right atrial septal defect and pulmonary hypertension), to group III (Eisenmenger Syndrome): (17.4 ng/mL, 21.8 ng/mL, and 29.4 ng/mL, respectively). A post-hoc analysis showed that serum soluble suppression of tumorigenicity-2 level was significantly different between groups I and III (p= 0.01). Serum N terminal pro brain natriuretic peptide (NT-proBNP) level was consistently associated with worse clinical and hemodynamic parameters. No correlation was found between serum soluble suppression of tumorigenicity-2 and NT-proBNP level. In conclusion, serum soluble suppression of tumorigenicity-2 level had significant positive correlation with mean pulmonary artery pressure and right ventricle end-diastolic diameter in uncorrected secundum atrial septal defect patients. Higher serum soluble suppression of tumorigenicity-2 level was associated with the presence of pulmonary hypertension and Eisenmenger Syndrome in uncorrected secundum atrial septal defect patients.

In electric agricultural machine a reduction gear is needed to convert the high speed rotation motion generated by DC motor to lower speed rotation motion used by the vehicle. The reduction gear consists of several spur gears. Spur gears are the most easily visualized gears that transmit motion between two parallel shafts and easy to produce. The modelling and simulation of spur gears in DC motor reduction gear is important to predict the actual motion behaviour. A pair of spur gear tooth in action is generally subjected to two types of cyclic stress: contact stress and bending stress. The stress may not attain their maximum values at the same point of contact fatigue. These types of failure can be minimized by analysis of the problem during the design stage and creating proper tooth surface profile with proper manufacturing methods. To improve its life expectation in this study modal and stress analysis of reduction gear is simulated using ANSYS workbench based on finite element method (FEM). The modal analysis was done to understand reduction gear deformation behaviour when vibration occurs. FEM static stress analysis is also simulated on reduction gear to simulate the gear teeth bending stress and contact stress behaviour.

A machine such as bean crusher machine is subjected to different loads and vibration. Due to this vibration there will be certain deformations which affect the performance of the machine in adverse manner. This paper proposed a vibration analysis of bean crusher machine using ANSYS. The effect of vibration on the structure was studied in order to ensure the safety using finite element analysis. This research supports the machine designer to create a better product with lower cost and faster development time. To do this, firstly, using Inventor, a CAD model is prepared. Secondly, the analysis is to be carried out using ANSYS 15. The modal analysis and random vibration analysis of the structure was conducted. The analysis shows that the proposed design was successfully shows the minimum deformation when the vibration was applied in normal condition.