No abstract

Resistance forces from the surface of snow acting on an alpine ski-skier system make the turning motion of the system possible. When the system has high velocity, the snow impacting force is predominant, while at low velocity, the snow cutting force plays a more important role. Using compact snow, we measure the three-dimensional compact snow cutting forces, apply multiple regression analysis to determine the empirical equations of these forces, and then use the resultant equations to simulate the turning motion of skis.

Background and study aims: We examined the efficacy of a novel endoscopic ligation technique with O-ring closure (E-LOC) to prevent bleeding after gastric endoscopic submucosal dissection (ESD). Patients and methods: This single-center prospective study involved consecutive patients who underwent gastric ESD with antithrombotic agents. E-LOC was performed by anchoring the nylon loop with hemoclips on both defect edges and/or the exposed muscle layer and using the O-ring band ligation around these deployed clips. The primary outcome was the post-ESD bleeding rate. The secondary outcomes were the complete closure rate, procedure time, sustained closure rate, and complications. Results: Forty-eight patients were finally analyzed. The post-ESD bleeding rate was 0%, the complete closure rate was 97.9%, and the mean closure time was 29.9 minutes. The sustained closure rate was 95.8% on postoperative day 2–3 and 33.3% on postoperative day 10–11. No complications occurred. Conclusions: E-LOC may be an effective option for closing mucosal defect after gastric ESD. However, the preventive effect on post-ESD bleeding should be further investigated in the high risk groups.

The primary photochemical process of Si2H6 at 193 nm has been studied by using time-resolved mass spectrometry and laser-induced fluorescence (LIF) techniques. Si2H2 was confirmed as a primary photoproduct, but no signal due to SiH3, Si2H3, Si2H4, and Si2H5 in 193 nm photolysis has been detected. SiH2 was observed in a pump-and-probe experiment by the LIF method, which rapidly reacts with the Si2H6 parent molecule to form Si3H8. The quantum yield of Si3H8 produced in the reaction of SiH2 + Si2H6 was estimated to be 0.13 ± 0.02 by using electron impact mass spectrometry. It was concluded that SiH2 produced by the photolysis exclusively reacted with Si2H6 and thus the quantum yield of SiH2 was equal to that of Si3H8, i.e., 0.13. The quantum yield of H atom was estimated to be 0.09 ± 0.01 by using vacuum ultraviolet (VUV) LIF. On the basis of the existing data and present results, it was suggested that the H2 molecule production channels are dominant in 193 nm photolysis of Si2H6.

Background and study aims Exposed endoscopic full-thickness resection (EFTR) enables the operator to obtain a sufficient surgical margin. However, insufflation leakage and secure endoscopic full-thickness closure (EFTC) remain problematic. This study aimed to evaluate the safety and feasibility of a new exposed EFTR. Patients and methods Exposed EFTR was performed for 2-cm virtual lesions in different locations of the upper stomach in four dogs. EFTR mainly involved half-circumferential EFTR of the endpoint and clip-line traction. Pulley traction was applied with the forward approach for the greater curvature. EFTC involved endoscopic ligation with O-ring closure to diminish insufflation leakage, followed by over-the-scope clip closure. Results Complete resection and technical success were achieved in all four cases. One case of intraoperative bleeding was endoscopically managed. No postoperative complications occurred in any cases. The median maximum resected size was 27.5 mm. The median procedure time of the total operation, EFTR, and EFTC was 76, 37, and 35.5 minutes, respectively. The 1-month survival rate was 100 %. Conclusions This therapeutic strategy may lead to the establishment of exposed EFTR.