A Systematic Review of Energy Harvesting from Biomechanical Factors

Conversion of human mechanical energy to usable electrical energy may seem like something from science fiction for the earliest generation of electronical engineers. But owing to the recent scientific advancements, it is no longer just a fiction but a reality. Researchers are working hard-time to improvise this idea by making attractive advancements in the field every day. This particular advancement gets much attention because it seems to be the most likely candidate to limit the usage of batteries, which have become a paradigm in the commercial world. Harvesting human energy can eliminate the limitations of scientific advancements in the portable and implantable devices due to the usage of batteries as their power source. There are several methods by which energy can be harvested from human activities, including but not restricted to thermoelectric generation, piezoelectric generation and triboelectric generation. These biomechanical phenomena can be tamed for commercial electricity usage under various circumstances. This paper provides a detailed review on these methods and the advancements made so far by researchers all around the globe.

Association of Mechanical Properties and Collagen Content With Valve Morphology in Ascending Thoracic Aortic Aneurysmal Tissue

Bicuspid aortic valve (BAV) is the most common congenital heart malformation occurring in 1–2% of the population with a high rate of morbidity [1]. There is a significantly higher rate of dilation of the aortic root in adults with a BAV when compared to the normal population and this condition is often associated with ascending thoracic aortic aneurysm (ATAA). ATAA is characterized as an enlargement of the aorta to twice its normal diameter. If left untreated, ATAA can lead to aortic dissection or rupture. Therefore, ATAA is recommended for prophylactic surgery when its diameter reaches about 5.5 cm. However, in certain high-risk cases, such as patients with BAV, ATAA may rupture when its diameter is less than 5.5 cm. Since ATAA dissection and rupture are biomechanical phenomena, better mechanical models are needed to more accurately predict these events over the predictive capability of diameter alone.

A Novel Bioreactor for the Flexural Stimulation of Tissue Engineered Heart Valve Biomaterials

A novel bioreactor was developed for the purpose of studying the effect of dynamic flexural stimulation on the properties of tissue engineered heart valve (TEHV) scaffolds and constructs. While pulse duplicator and flow loop bioreactors have shown promise in the development of functional tissue engineered cardiovascular constructs [1–3], these devices present several drawbacks when applied to the study of fundamental biomechanical phenomena, including: small sample capacity, anatomical sample geometry, and coupled mechanical stimuli. In contrast, our bioreactor was designed to provide a simple, user-controllable mode of mechanical stimulation; cyclic three-point bending; offer a sufficient sample capacity for statistically significant comparisons at multiple time points, and accommodate a simple sample geometry amenable to mechanical testing. The bioreactor has the capacity to dynamically flex twelve rectangular samples (2.5 × 0.75 × 0.2 cm) under sterile conditions in a humidified cell culture incubator operating at 37 °C and 5% CO2 (Figure 1).