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Skin lacerations are not fatal but constitute one of the most common injuries in daily life. There is a need, therefore, for measures to prevent skin lacerations caused by accidents; however, since only a few engineering studies have been undertaken, the threshold of skin laceration is still unclear. In this study, the thresholds of skin laceration under moderate loading rate are proposed according to the results of penetration tests on porcine skin using a knife or blunt blade. In the tests, a sharp blade (knife) and blunt blade with an edge having a small radius of curvature were applied to the external surfaces of dorsal and ventral porcine skin specimens. Penetration tests using sharp blades showed that the average rupture load was 39.0N for dorsal skin and 36.0N for ventral skin. On the other hand, the results of the penetration tests using the blunt blade were statistically analyzed by ordinal logistic regression, because the rupture load could not be defined precisely based on the load sequence data. The regression curves show that the rupture loads for a 50% probability were within the range of 123.7N to 214.4N for dorsal region skin and 80.1N to 160.0N for ventral region skin.

Tissue Optical Clearing Devices (TOCDs) have been shown to increase light transmission through mechanically compressed regions of naturally turbid biological tissues. We hypothesize that zones of high compressive strain induced by TOCD pins produce localized water displacement and reversible changes in tissue optical properties. In this paper, we demonstrate a novel combined mechanical finite element model and optical Monte Carlo model which simulates TOCD pin compression of an ex vivo porcine skin sample and modified spatial photon fluence distributions within the tissue. Results of this simulation qualitatively suggest that light transmission through the skin can be significantly affected by changes in compressed tissue geometry as well as concurrent changes in tissue optical properties. The development of a comprehensive multi-domain model of TOCD application to tissues such as skin could ultimately be used as a framework for optimizing future design of TOCDs.

One of the major challenges in imaging biological tissues using optical techniques, such as optical coherence tomography (OCT), is the lack of light penetration due to highly turbid structures within the tissue. Optical clearing techniques enable the biological samples to be more optically homogeneous, allowing for deeper penetration of light into the tissue. This study investigates the effect of optical clearing utilizing various concentrations of glucose solution (10%, 30%, and 50%) on porcine skin. A gold-plated mirror was imaged beneath the tissue and percentage clearing was determined by monitoring the change in reflected light intensity from the mirror over time. The ratio of percentage clearing per tissue thickness for 10%, 30% and 50% glucose was determined to be 4.7 ±1.6% mm^-1 (n = 6), 10.6 ±2.0% mm^-1 (n = 7) and 21.8 ±2.2% mm^-1 (n = 5), respectively. It was concluded that while higher glucose concentration has the highest optical clearing effect, a suitable concentration should be chosen for the purpose of clearing, considering the osmotic stress on the tissue sample.