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Go to Editorial ManagerThe assessment of prosthetic aortic valves through echocardiography, a pivotal noninvasive tool, encounters challenges, with discordant findings compared to invasive measurements, particularly in transvalvular gradients. To address these complexities, this comprehensive review article explores diverse methodologies and modalities for assessing prosthetic aortic valve performance. As these life-saving devices advance in complexity, the demand for precise and innovative assessment techniques intensifies. This journey through established and emerging modalities aims to inform clinical practice, foster experimental innovation, and enhance patient care in the realm of aortic valve prosthetic assessment. Ultimately, a profound understanding of the hemodynamic milieu engendered by aortic prosthetic valves serves as the cornerstone for optimizing valve design and clinical utility. The primary objective of this comprehensive review is to elucidate, with utmost precision, the multifaceted methodologies employed in the investigation and evaluation of mechanical prosthetic aortic valve.
This study aims to enhance the compression strength in one type of Pb-Sn-Sb alloys which wellknown by (Babbitt-ASTM B23 Alloy 13). The ?processing doing via equal channel angular extrusion technique. Three casting were implemented to ?manufacture the alloy; Chill Casting (CC), New Rheocasting (NRC) and Gravity Die Casting (GDC). The ?microscope examination shows that the microstructures contain two phases, ?-Pb and cubic shaped ?intermetallic compound (?-SbSn) in a matrix of ternary phases. CC was fine equiaxed as well as NRC, while ?in GDC was a dendrite ?-Pb phase with remaining ?-SbSn phase as a cubic shape. Higher mechanical properties in compression were recorded for Gravity die casting (12.7 %) while the NRC registered the highest value in yield strength (11.7 %). On the other hand, the casting techniques had a slight difference in Young's modulus. The other resulted data like hardness showed that NRC is the first reading (12.55 %) and then gravity casting recorded as second score comparing with other (11.79 %), The results ?showed aslo that increasing forming temperature during angular extrusion has an adverse effect on compression ?strength. The study ?concluded that microstructural change caused by ECAP softens the material due to the break-up the original ? precipitate and accelerate from the dynamic recrystallization.
The purpose of this research is to manufacture and test adjustable sockets for below-knee amputation. This article studies using the pnuematic–pads for adjustable sockets. The manufacturing of an adjustable socket with pneumatic pads goes through several stages: In the theoretical design of the adjustable socket, the suggested materials were studied for the pneumatic pads, tubes, and pneumatic pump which should be suitable for the suggested application. In the experimental work, using composite materials for manufacturing the socket consisting of perlon and resin to achieve the rigid shape and required flexibility for the prosthetic user with the pneumatic pads. After assembling the adjustable socket parts, the pneumatic pads, the pump and the tubes, the socket were tested for several times on the patient. In the last stage, the pressure between the socket and the residual limb was measured using F-socket, and it was found that the results were: anterior (160kPa), lateral (167kPa), posterior (153kPa) and medial (348kPa). By comparing these results with what was previously studied, the pressure between the socket and the residual limb is within the acceptable range. The design provides good suspension and more adaptability to the change in stump volume. A posative feedback was given by the patient who used the prosthetic patient for several days as a trial to measure its safety and comfortablty.