An investigation of fat-tailed distributions in fitting the Japanese stock market returns

The Tokyo Stock Exchange (TSE) is the fourth largest stock exchange in the world by aggregate market capitalization of its listed companies and largest in East Asia and Asia. It is of great importance for those in charge of managing risk to understand how its market index returns are distributed. The goal of this paper is to examine how various types of heavy-tailed distribution perform in risk management of the N225 Index returns. We compared these heavy-tailed distributions through a variety of criteria. Our results indicate the generalized hyperbolic distribution has the best goodness of fit and generates most suitable risk measures.peer-reviewe

The International Surface Pressure Databank version 2

The International Surface Pressure Databank (ISPD) is the world's largest collection of global surface and sea-level pressure observations. It was developed by extracting observations from established international archives, through international cooperation with data recovery facilitated by the Atmospheric Circulation Reconstructions over the Earth (ACRE) initiative, and directly by contributing universities, organizations, and countries. The dataset period is currently 1768–2012 and consists of three data components: observations from land stations, marine observing systems, and tropical cyclone best track pressure reports. Version 2 of the ISPD (ISPDv2) was created to be observational input for the Twentieth Century Reanalysis Project (20CR) and contains the quality control and assimilation feedback metadata from the 20CR. Since then, it has been used for various general climate and weather studies, and an updated version 3 (ISPDv3) has been used in the ERA-20C reanalysis in connection with the European Reanalysis of Global Climate Observations project (ERA-CLIM). The focus of this paper is on the ISPDv2 and the inclusion of the 20CR feedback metadata. The Research Data Archive at the National Center for Atmospheric Research provides data collection and access for the ISPDv2, and will provide access to future versions

Lateral lymph node recurrence of rectal cancer with a pathological complete response to chemotherapy confirmed by laparoscopic lateral lymph node dissection : A case report

Lateral lymph node (LLN) metastasis is one of the forms of local recurrence after surgery for lower rectal cancer. We here present a case of LLN recurrence of rectal cancer that was shown by laparoscopic lateral lymph node dissection (LLND) to have a complete pathological response to chemotherapy. A 58-year-old man underwent open low anterior resection for lower rectal cancer. After detection of right LLN recurrence 43 months after the operation, 11 cycles of capecitabine, oxaliplatin, and bevacizumab chemotherapy were administered. Laparoscopic right LLND was performed 55 months after the first operation. Pathological examination revealed no viable tumor cells in the dissected lymph nodes. The patient remains alive without recurrence 61 months after the first surgery and 6 months after laparoscopic LLND. Laparoscopic LLND for LLN recurrence of rectal cancer is feasible and should be considered a valid treatment option

A Study of risk factors of postoperative ileus after laparoscopic colorectal resection

Abstract Aim Postoperative ileus (POI) is a common complication after abdominal surgery. However, the risk factors for POI after laparoscopic colorectal resection are unclear. We therefore investigated the risk factors for POI after laparoscopic colorectal surgery. Methods This retrospective study involved 484 patients who underwent laparoscopic surgery for primary colorectal cancer at Hokkaido University Hospital. We categorized the patients into a POI group (n = 19) and non‐POI group (n = 465). We compared sex, age, smoking, chronic obstructive pulmonary disease (COPD), diabetes mellitus, body mass index (BMI), cardiac disorder, serum albumin, American Society of Anesthesiologists‐physical status, tumor location, tumor stage, operative duration, stoma formation, lymph node dissection, operator, and bleeding as potential risk factors for POI between the POI group and non‐POI group by univariate and multivariate analyses. Results The univariate analysis results showed that the POI group had a higher incidence of male sex (P = 0.036), COPD (P = 0.029), and a BMI of <20 kg/m2 (P = 0.0487) as well as a higher bleeding volume (P = 0.014). The multivariate analysis results showed that male sex (odds ratio [OR], 0.2799; 95% confidence interval [CI], 0.089–0.993; P = 0.0298), COPD (0.2866; 0.095–0.862; P = 0.0262), and a BMI of <20 kg/m2 (0.2985; 0.112–0.794; P = 0.0154) were independent risk factors for POI after laparoscopic colorectal resection. Conclusion Our findings suggest that male sex, COPD, and a BMI of <20 kg/m2 are independent risk factors for POI after laparoscopic colorectal surgery for treatment of colorectal cancer

Combined Laparoscopic and Transperineal Endoscopic Pelvic Tumor Resection with Sacrectomy for Locally Recurrent Rectal Cancer

Pelvic tumor resection with sacrectomy for locally recurrent rectal cancer is a challenging operation with a high complication rate and poor prognosis. We report a case of pelvic tumor resection with sacrectomy by transperineal endoscopy following laparoscopic dissection for locally recurrent rectal cancer. A 70-year-old man underwent laparoscopic abdominoperineal resection for rectal cancer and was diagnosed with local pelvic recurrence on follow-up computed tomography (CT) three years postoperatively. As the recurrence was in contact with the front of the sacrum, we concluded that distal sacrectomy was necessary to ensure a surgical margin. We safely performed combined laparoscopic and transperineal endoscopic pelvic tumor resection with sacrectomy by exposing the surface of the sacrum from both abdominal and transperineal approach. The operative time was 200 minutes, with minimal blood loss. There was no tumor exposure on the surgically dissected surface, and the patient was discharged without complications 14 days postoperatively. Transperineal endoscopy may be useful for pelvic tumor resection with sacrectomy for locally recurrent rectal cancer

Exploration of the advantages of minimally invasive surgery for clinical T4 colorectal cancer compared with open surgery : A matched-pair analysis

The indications of minimally invasive surgery (MIS) for T4 colorectal cancer are controversial because the advantages of MIS are unclear. Therefore, we compared overall survival (OS) and recurrence-free survival (RFS) as the primary endpoint, and short-term outcome, alteration in perioperative laboratory data, and the interval of postoperative chemotherapy from operation as secondary endpoints, between MIS and open surgery (OPEN) using a matched-pair analysis. We explored the advantages of MIS for T4 colorectal cancer. In this retrospective single-institution study, we included 125 patients with clinical T4 colorectal cancer who underwent curative-intent surgery of the primary tumor between October 2010 and September 2019. Conversion cases were excluded. MIS patients were matched to OPEN patients (ratio of 1:2) according to tumor location, clinical T stage, and preoperative treatment. We identified 25 and 50 patients who underwent OPEN and MIS, respectively, including 31 with distant metastasis. Both groups had similar background characteristics. The rate of major morbidities (Clavien-Dindo grade > III) was comparable between the 2 groups (P = .597), and there was no mortality in either group. MIS tended to result in shorter postoperative hospitalization than OPEN (P = .073). Perioperative alterations in laboratory data revealed that MIS suppressed surgical invasiveness better compared to OPEN. Postoperative chemotherapy, especially for patients with distant metastasis who underwent primary tumor resection, tended to be started earlier in the MIS group than in the OPEN group (P = .075). OS and RFS were comparable between the 2 groups (P = .996 and .870, respectively). In the multivariate analyses, MIS was not a significant prognostic factor for poor OS and RFS. MIS was surgically safe and showed similar oncological outcomes to OPEN-with the potential of reduced invasiveness and enhanced recovery from surgery. Therefore, patients undergoing MIS might receive subsequent postoperative treatments earlier

Ischemic proctitis 6 months after laparoscopic sigmoidectomy: a case report

Background Ischemic colitis is a common disease; however, its pathophysiology remains unclear, especially in ischemic proctitis after sigmoidectomy. We present a rare case of ischemic proctitis 6 months after laparoscopic sigmoidectomy. Case presentation The patient was a 60-year-old man with hypertension, type 2 diabetes, and hyperlipidemia. He was a smoker. He underwent laparoscopic sigmoidectomy for pathological stage I sigmoid colon cancer and was followed up without any adjuvant therapy. Six months after his surgery, he complained of lower abdominal discomfort, bloody stools, and tenesmus. Colonoscopy showed extensive rectal ulcers between the anastomotic site and the anal canal, which was particularly severe on the anal side several centimeters beyond the anastomosis. We provided non-surgical management, including hyperbaric oxygen therapy. The rectal ulcers had healed 48 days after the therapeutic intervention. He has not experienced any recurrence for 3.5 years. Conclusions While performing sigmoidectomy, it is important to consider the blood backflow from the anal side of the bowel carefully, especially for patients with risk factors of ischemic proctitis