Evaluation and consideration of local specimen material properties in lifetime prediction of short fibre reinforced PA6T/6I

To exploit the full material potential of short fibre reinforced PA6T/6I, specific component calculations including aniso- tropic material behaviour is necessary. For this, different failure criteria and fatigue models are used to describe the behaviour during a component service life. This paper deals with the determination and consideration of fibre orientations for failure criteria and fatigue calculations. Therefore, a novel method to determine fibre orientation (FO) distributions across injection moulded plates, is proposed. The developed method allows a forecast of FOs for different specimen extraction positions and angles on injection moulded plates by using only a few measured reference points. As a result, fatigue models can be calibrated with the strength values and the corresponding FO, calculated for fracture position. The performed tests show a non-negligible influence of failure positions, due to fibre orientation distributions along the specimens. So, the FO determination method delivers an improvement in strength values estimation.

Application of a Temporary Ileostomy via Median Specimen Extraction Site in Laparoscopic Low Anterior Resection

Objective: To evaluate the feasibility and safety of temporary ileostomy via median specimen extraction site in the lower abdomen. Methods: Twenty-two patients who underwent laparoscopic radical resection for rectal cancer and needed temporary ileostomy were prospectively enrolled. Temporary ileostomy was placed on the median specimen extraction site of the lower abdomen. Intraoperative and postoperative conditions, stoma-related complications and ileostomy reversal surgery were observed. d. Results: Among the 22 patients, there were 14 female patients and 8 male patients: the average age was 56 ±14 years; the average body mass index was 22.0 ±3.4 kg/m2; the average tumour size was 4.4 ±2.2 cm; the average distance between the tumour and the dentate line was 5.9 ±2.3 cm; the average time of laparoscopic low anterior resection was 221 ±56 minutes; the average blood loss was 168 ±91 ml; and the average postoperative hospital stay was 9.9 ±3.9 days. The average ileostomy reversal surgery time was 72 ±15 minutes, the average blood loss was 50 ±27 ml, and the average postoperative hospital stay was 5.9 ±1.0 days. Stoma-related complications occurred in 5 patients, of which one was treated by emergency surgery. Conclusion: In laparoscopic low anterior resection, patients with temporary ileostomy via the median specimen extraction site did not have serious complications that required surgical intervention during hospitalization, and there was no mortality during the perioperative period. It is safe and feasible to perform temporary ileostomies via the median specimen extraction site in the lower abdomen, but for permanent ileostomies, the median site in the lower abdomen should be carefully selected as the ileostomy site.