Long-term stable excitons, bound pairs of electrons and holes, in van der Waals materials were found to be handled at room temperature, paving the way to develop optoelectronic/photonic devices for future high-speed communication technology. To miniaturize and integrate such functions to achieve highly efficient excitonic devices, understanding and manipulation of exciton dynamics in the nanoscale structures is absolutely essential. Since the spatial resolution of the optical techniques, which have been mainly used in the research of this field, is limited to μm to several tens of nm, the introduction of new technology is strongly desired. Here, we demonstrate a method to probe and visualize neutral excitons using the laser-combined multiprobe scanning tunneling microscopy (STM) system. Ultrafast dynamics of excitons in the nanostructures produced in an in-plane WS2/WSe2 heterostructure, such as dynamics in the ps region of many-body effects under high density and spatial variation in the effect of local defects on lifetime, was successfully revealed with a spatial resolution of 1 nm order. This method is expected to accelerate research on exciton dynamics and the development of applications directly based on the experimental results of nanoscale.

Introduction:In rectal surgery, double-stapled anastomosis is one of the most common techniques. However, the crossing of the staple line is considered a weakness of this method and could lead to anastomotic leakage (AL), which is one of the major complications of rectal cancer surgery. Aim: To investigate the usefulness of laparoscopic intracorporeal reinforcement suturing for preventing AL in laparoscopic rectal surgery. Material and methods: A total of 153 patients with rectal cancer underwent laparoscopic rectal resection with anastomosis using the double-stapling technique between January 2015 and December 2018. Patient characteristics, surgical data, and outcomes were recorded and retrospectively analysed. Patients who received intracorporeal reinforcing sutures (n = 72) were compared with those who did not receive the reinforcing sutures (n = 81). Results: AL was observed in 11 (7.2%) cases overall and in only 1 case in the group with intracorporeal reinforcing sutures. There were no associations between clinicopathological factors and the use of reinforcing sutures. Multivariate analysis revealed that a distance from the anal verge of less than 6.5 cm, diabetes mellitus, and the non-use of reinforcing sutures were independent risk factors for AL. Conclusions: Laparoscopic intracorporeal reinforcing sutures reduced the incidence of AL. Therefore, laparoscopic reinforcing sutures for double-stapled anastomoses seem useful for the prevention of AL.

Highlights Diaphragm disease is a rare NSAIDs-induced injury of the small intestine. Diaphragm disease is mostly surgically treated. Diagnosis with double-balloon enteroscopy can be considered for diaphragm disease.

Background: Colostomy via the intraperitoneal route is often performed during laparoscopic Hartmann's operation or abdominoperineal resection. Internal hernia of the small intestine often occurs after colostomy. This report shows a rare case of internal hernia of the stomach associated with sigmoid colostomy after laparoscopic abdominoperineal resection for rectal cancer. Case presentation: The patient was a 79-year-old woman with a sigmoid colostomy. Computed tomography scan showed a markedly distended stomach in the space between the lifted sigmoid colon and the lateral abdominal wall. Laparoscopy revealed that the body of the stomach had passed through a hernia orifice located between the lifted sigmoid colon and the left lateral abdominal wall. The dislocated stomach was restored to its normal position, and the lateral defect was closed with the lateral peritoneum and the lifted sigmoid colon laparoscopically. Conclusions: Internal hernia associated with colostomy can lead to not only obstruction of the small intestine, but also obstruction of the stomach. We reported a successful case of the suture repair for the internal hernia of the stomach associated with colostomy.

Background: Super-elderly patients with colorectal cancer are being encountered with increasing frequency in Japan. Laparoscopic surgery is considered a less invasive surgery in these patients; however, it is difficult to conduct controlled clinical trials in this super-elderly population. This study assessed the feasibility and safety of laparoscopic colorectal surgery in patients over 85 years old.Materials and Methods: Open and laparoscopic surgeries for colorectal cancer in super-elderly patients (aged 85 y and older) were performed under general anesthesia in a single medical center. Records were retrospectively reviewed, and the clinicopathologic features of each patient and the surgical time and outcomes were recorded and analyzed.Results: Records of colorectal surgery were reviewed for 108 super-elderly patients. Twenty-six open surgeries and 82 laparoscopic surgeries were performed. The mean operation times were 215 and 228 minutes in open and laparoscopic surgeries, respectively. Intraoperative bleeding in laparoscopic surgery was lesser than that in open surgery. There were 2 cases with major postoperative complications in open surgery, and mortality occurred in one case within 1 month after surgery. No major complications were observed in laparoscopic surgery. In survival analysis, disease-free survival did not differ between the 2 groups. The oldest patient was a man aged 102 years and 6 months who underwent laparoscopic anterior resection with lymph node dissection. Conclusion:Laparoscopic surgery in super-elderly patients with colon cancer is feasible and safe. The authors report the success of laparoscopic colectomy for rectosigmoid colon cancer in the oldest known patient and the positive outcomes of laparoscopic colectomy in super-elderly patients.