Search

Background Nonthermal atmospheric pressure plasma (NTAPP) has recently received attention as a novel tool in medicine. It is thought that plasma components yield plasma effects such as sterilization, blood coagulation, and wound healing. These effects are produced without thermal damage. We investigated the blood coagulation effect of NTAPP by using a multigas plasma jet. Materials and methods Multigas plasma jets can generate NTAPP by several gas species. In this study, argon, oxygen, helium, nitrogen, mock air, and carbon dioxide were used to generate NTAPP, and blood coagulation times were compared with each plasma-treated sample. The NTAPP blood coagulation effects on whole blood with four different anticoagulants were investigated. In addition, in this study, the effects of plasma treatment on porcine tissues and organs were investigated as in vivo experiment. Results A tendency to coagulate later with argon gas plasma than others was shown. There were no significant differences between oxygen, helium, nitrogen, mock air, and carbon dioxide. Whole blood with each anticoagulant demonstrated fast coagulation by NTAPP treatment. Fast control of the bleeding lesions on porcine stomach and liver by plasma treatment was observed, and no tissue damage due to the plasma treatment was detected by optical microscope. Conclusions These experiments suggest the potential of various gas NTAPPs as a novel medical device to control bleeding lesions.

In the medical field, demand for endoscopes has been increasing not only for examination but also for minimally invasive treatment. For endoscopic hemostasis, clips and plasma devices called Argon Plasma Coagulation (APC) are widely used. Although APC has a short hemostasis time, there is a problem with a tissue that is thermally damaged by high plasma temperature. Meanwhile, promotion of blood coagulation by atmospheric low temperature plasma has been reported. Blood points irradiated with the plasma can clot without thermal damage and stop bleeding. Therefore, applying atmospheric low temperature plasma to endoscopic hemostasis can be expected as a minimally invasive hemostatic method. For that purpose, a mini plasma source that can be inserted into a forceps port of endoscope is required. However, conventional plasma source had been manufactured by machining, there was limitation for miniaturization.

The full-filed evaluation of the isoclinic parameter in digital photoelasticity is presented. The proposed method is based on the four-step color phase shifting technique and the phase unwrapping (PU) algorithm. It is experimentally applied to an eccentrically loaded split ring (C-shaped model). Experimental results show that the isoclinic-angle map obtained is almost free from the influence of the isochromatic parameter and the isoclinic values lie in the physical range, −π/2 to +π/2, regardless of the presence of the isotropic point or region.

A phase unwrapping (PU) algorithm for processing fractional fringes photoelastically obtained using an arccosine operator is presented. The PU algorithm works with three primary wavelengths RGB of white light source. The three fractional fringe values at a point are used to generate a plane. One point in the fringe fields is automatically chosen to be the seed point. A set of selected fringe values from fringe candidates is chosen and adjusted with certain conditions. The circular disk under compression demonstrates the performance of the proposed PU algorithm.