Characteristics of vertical type polymer light emitting transistor using dimethyldicyanoquinonediimine as a N-type buffer layer.

Contact resistance between a metal electrode and an organic active layer is one of the most critical issues in the research and development of organic electronic devices. In the present work, we have fabricated vertical type organic light emitting transistor (OLET) using P3HT as a organic active semiconductor and DMDCNQI as a charge transfer material. The device configuration is ITO/PEDOT:PSS/P3HT/Al gate/P3HT/DMDCNQI/Al. The characteristics of OLET were investigated from the measurement of current-radiance voltage characteristics The needle form of highly conducting DMDCNQI-Al charge transfer complex was obtained, which resulted in the improvement of device performance due to the low organic-metal contact resistance and the high electron transport ability.

The learning curve for laparoscopic totally extraperitoneal herniorrhaphy by moving average.

PURPOSE: Laparoscopic totally extraperitoneal (TEP) herniorrhaphy has been recognized as a treatment option for inguinal hernia. The objective of this study was to clarify the learning curve for laparoscopic TEP herniorrhaphy using the moving average method. METHODS: A total of 90 patients underwent laparoscopic TEP herniorrhaphy by a single surgeon between March 2009 and March 2011. We analyzed medical records including the demographic data, operating time, hospital stay, and postoperative complications. RESULTS: The mean operating time of the initial 30 cases (learning period group) was 66.3 minutes. After the initial 30 cases were performed, the time decreased to 52.8 minutes in the later 60 cases (experienced period group, P = 0.015). This represents the operating time becoming stabilized and then decreasing as the number of performed cases accumulates. Hospital stay was shorter and frequency of pain control, and complication rate were lower in the experienced period, however, there was no statistical significance. CONCLUSION: We suggest that number of patients needed for the learning curve for laparoscopic TEP herniorrhaphy should be 30 cases. The operating time for laparoscopic TEP herniorrhaphy stabilizes after 40 cases in moving average analysis.

Mesenteric pseudocyst of the small bowel in gastric cancer patient: a case report.

Mesenteric pseudocyst is rare. This term is used to describe the abdominal cystic mass, without the origin of abdominal organ. We presented a case of mesenteric pseudocyst of the small bowel in a 70-year-old man. Esophago-gastro-duodenoscopy showed a 3.5 cm sized excavated lesion on the posterior wall of angle. Endocopic biopsy confirmed a histologic diagnosis of the poorly differentiated adenocarcinoma, which includes the signet ring cell component. Abdominal computed tomography scan showed a focal mucosal enhancement in the posterior wall of angle of the stomach, a 2.4 cm sized enhancing mass on the distal small bowel loop, without distant metastases or ascites in rectal shelf, and multiple gallbladder stones. The patient underwent subtotal gastrectomy with gastroduodenostomy, segmental resection of the small bowel, and cholecystectomy. The final pathological diagnosis was mesenteric pseudocyst. This is the first case report describing incidentally detected mesenteric pseudocyst of the small bowel in gastric cancer patients.

The peak-standardized uptake value (P-SUV) by preoperative positron emission tomography-computed tomography (PET-CT) is a useful indicator of lymph node metastasis in gastric cancer.

BACKGROUND AND OBJECTIVES: Little data is currently available on the usefulness of peak-standardized uptake value (P-SUV) by positron emission tomography-computed tomography (PET-CT) in gastric cancer. The purpose of the present study was to evaluate the value of PET-CT for the preoperative evaluation of patients with gastric cancer. The aim of this study was to assess the relation of between primary tumor P-SUV, as determined by preoperative PET-CT, and lymph node metastasis in gastric cancer. METHODS: From December 2007 to March 2010, we analyzed the PET-CT of 147 patients that underwent gastrectomy for gastric cancer. P-SUV in PET-CT were measured by single nuclear medicine physician. Statistical analysis was performed to determine relations between clinicopathologic parameters including P-SUV and lymph node metastasis using the chi-square test, the independent t-test, and using logistic regression analysis. RESULTS: Age, tumor depth, tumor size, and lymph node metastasis were found to be associated with primary tumor P-SUV by PET-CT (P=0.009, <0.001, <0.001, and <0.001, respectively). No association was found between P-SUV and tumor histology or tumor location (P=0.099). Advanced gastric cancer was found to have a higher P-SUV than early gastric cancer, and a higher P-SUV was found to be associated with lymph node metastases by both univariate and multivariate analysis. CONCLUSIONS: P-SUV of primary tumor could be an independent indicator of lymph node metastasis in gastric cancer. Gastric surgeons should pay more attention to the dissection of lymph nodes when primary tumors have higher P-SUV values by PET-CT.

Characteristics and fabrication of vertical type organic light emitting transistor using dimethyldicyanoquinonediimine (DMDCNQI) as a n-type active layer and light emitting polymer.

We have investigated electrical properties of vertical type organic transistor using dimethyldicyanoquinonediimine (DMDCNQI) as a n-type active layer. And also, the contact resistance Ro for charge injection from a metal electrode to an organic semiconductor layer was studied by transfer line method. The radiance of organic light emitting transistor (OLET) consisting of glass/ITO (drain)/PEDOT:PSS/MEH-PPV/DMDCNQI/Al (gate)/DMDCNQI/Au (source) can be effectively controlled by applying gate voltage like depletion mode.

Comparison of Bile Drainage Methods after Laparoscopic CBD Exploration.

PURPOSE: T-tube is a major procedure that prevents complication by biliary decompression, but which is accompanied by complications. Therefore, several procedures such as ENBD, PTBD, and antegrade biliary stent have been attempted, but with controversies as to which procedure is superior. Also, there are no standard procedures after laparoscopic CBD exploration. We performed this study to ascertain the most appropriate biliary drainage procedure after laparoscopic CBD exploration. METHODS: From March 2001 to December 2009, 121 patients who underwent Laparoscopic CBD exploration in Gunyang University were included for retrospective analysis. The patients were divided to 4 groups according to type of procedure, and we compared clinical parameters including age and gender, operation time, hospital stay, start of post-operative diet, and complications. RESULTS: There was no difference in age, gender, mean operation time, postoperative diet between the 4 groups. Hospital stay in the Stent group was shorter than T-tube group. There were 10 (7%) complications that occurred. Two 2 occurred in the T-tube, 3 in PTBD, and 5 in the Antegrade stent group. There were more complications in Stent group but no significant statistical difference. In 5 cases with remnant CBD stone, a total of 4 (3 PTBD, 1 Stent) was performed by endoscopic CBD stone removal. One T-tube case was removed easily by choledochoscopy through the T-tube. Three migrated and the impacted stents were removed by additional endoscopy. Perioperative biliary leakage (1) and peritonitis (1) post t-tube removal were resolved by conservative treatment. CONCLUSION: T-tube appears to be an appropriate method to patients who are suspected to have remnant CBD stones. Multiple procedures may be performed on a case by case basis such as performing PTBD first in a suspected cholangitis patient.