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PURPOSE Adjuvant chemotherapy after D2 gastrectomy is standard for resectable locally advanced gastric cancer (LAGC) in Asia. Based on positive findings for perioperative chemotherapy in European phase III studies, the phase III PRODIGY study (ClinicalTrials.gov identifier: NCT01515748 ) investigated whether neoadjuvant docetaxel, oxaliplatin, and S-1 (DOS) followed by surgery and adjuvant S-1 could improve outcomes versus standard treatment in Korean patients with resectable LAGC. PATIENTS AND METHODS Patients 20-75 years of age, with Eastern Cooperative Oncology Group performance status 0-1, and with histologically confirmed primary gastric or gastroesophageal junction adenocarcinoma (clinical TNM staging: T2-3N+ or T4Nany) were randomly assigned to D2 surgery followed by adjuvant S-1 (40-60 mg orally twice a day, days 1-28 every 6 weeks for eight cycles; SC group) or neoadjuvant DOS (docetaxel 50 mg/m2, oxaliplatin 100 mg/m2 intravenously day 1, S-1 40 mg/m2 orally twice a day, days 1-14 every 3 weeks for three cycles) before D2 surgery, followed by adjuvant S-1 (CSC group). The primary objective was progression-free survival (PFS) with CSC versus SC. Two sensitivity analyses were performed: intent-to-treat and landmark PFS analysis. RESULTS Between January 18, 2012, and January 2, 2017, 266 patients were randomly assigned to CSC and 264 to SC at 18 Korean study sites; 238 and 246 patients, respectively, were treated (full analysis set). Follow-up was ongoing in 176 patients at data cutoff (January 21, 2019; median follow-up 38.6 months [interquartile range, 23.5-62.1]). CSC improved PFS versus SC (adjusted hazard ratio, 0.70; 95% CI, 0.52 to 0.95; stratified log-rank P = .023). Sensitivity analyses confirmed these findings. Treatments were well tolerated. Two grade 5 adverse events (febrile neutropenia and dyspnea) occurred during neoadjuvant treatment. CONCLUSION PRODIGY showed that neoadjuvant DOS chemotherapy, as part of perioperative chemotherapy, is effective and tolerable in Korean patients with LAGC.

A ZnMgO and ZnO double-layered structure was prepared to create a stepwise interfacial electronic structure to improve the electron-injection and electron-transport behaviors in quantum-dot light-emitting diodes (QLEDs). The current density of the electron-only device (EOD) with ZnMgO/ZnO was higher than that of the EOD with only ZnMgO. The detailed QLED interfacial electronic structure was measured using X-ray and ultraviolet photoelectron spectroscopy. A stepwise interfacial electronic structure for electron injection and electron transport was observed connecting the aluminum cathode to the ZnMgO conduction band minimum (CBM) via the ZnO CBM. The QLEDs with the ZnMgO/ZnO double electron transport layer showed an improved performance, with a maximum luminance and current efficiency of 90,892 cd m−2 and 19.2 cd A−1, respectively. Moreover, the turn-on voltage of the device was significantly reduced to 2.6 V due to the stepwise interfacial electronic structure between the aluminum cathode and ZnMgO CBM. This research provides a useful method for developing highly efficient and low turn-on voltage QLEDs using a ZnMgO/ZnO double ETL for next-generation display.

BACKGROUND Although several methods of totally laparoscopic total gastrectomy (TLTG) have been reported. The best anastomosis technique for LTG has not been established. AIM To investigate the effectiveness and surgical outcomes of TLTG using the modified overlap method compared with open total gastrectomy (OTG) using the circular stapled method. METHODS We performed 151 and 131 surgeries using TLTG with the modified overlap method and OTG for gastric cancer between March 2012 and December 2018. Surgical and oncological outcomes were compared between groups using propensity score matching. In addition, we analyzed the risk factors associated with postoperative complications. RESULTS Patients who underwent TLTG were discharged earlier than those who underwent OTG [TLTG (9.62 ± 5.32) vs OTG (13.51 ± 10.67), P < 0.05]. Time to first flatus and soft diet were significantly shorter in TLTG group. The pain scores at all postoperative periods and administration of opioids were significantly lower in the TLTG group than in the OTG group. No significant difference in early, late and esophagojejunostomy (EJ)-related complications or 5-year recurrence free and overall survival between groups. Multivariate analysis demonstrated that body mass index [odds ratio (OR), 1.824; 95% confidence interval (CI): 1.029-3.234, P = 0.040] and American Society of Anaesthesiologists (ASA) score (OR, 3.154; 95%CI: 1.084-9.174, P = 0.035) were independent risk factors of early complications. Additionally, age was associated with ≥ 3 Clavien-Dindo classification and EJ-related complications. CONCLUSION Although TLTG with the modified overlap method showed similar complication rate and oncological outcome with OTG, it yields lower pain score, earlier bowel recovery, and discharge. Surgeons should perform total gastrectomy cautiously and delicately in patients with obesity, high ASA scores, and older ages.

Background Gastric neuroendocrine carcinomas (NECs), consisting of both large- and small-cell NECs, and mixed adenoneuroendocrine carcinomas (MANECs), including mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs), are a group of high-grade malignancies. Few studies to date have reported clinical outcomes, including prognosis, in patients with these tumors. This study therefore evaluated the clinicopathologic outcomes and prognosis in patients with NECs and MANECs. Methods This study included 36 patients diagnosed with gastric NECs, including 23 with large-cell and 13 with small-cell NECs, and 85 with MiNENs, including 70 with high-grade and 15 with intermediate-grade MiNENs. Clinical outcomes, including overall survival (OS) and disease-free survival (DFS), were assessed. Results DFS was significantly poorer in patients with NEC than in patients with intermediate-grade MiNEN ( P < .05), whereas both OS and DFS were similar in patients with NEC and high-grade MiNEN ( P > .05). Patients with large-cell NEC were more likely to undergo aggressive surgery than patients with high-grade MiNEN ( P < .05). Lymphovascular invasion was more frequent and DFS poorer in patients with large-cell than small-cell NECs ( P < .05 each). Conclusion DFS is significantly poorer in patients with NEC than in patients with intermediate-grade MiNEN and significantly lower in patients with large-cell than small-cell NECs.

In recent years, there are an increase in the mortality rate due to Chronic obstructive pulmonary disease (COPD) patients and it is estimated that it will increase in the coming years. Traditional methods take a long time to identify these diseases because a lot of clinical tests has to be performed for getting the confirmation, however with the advent of intelligent techniques as well as looking at the potential of the powerful techniques for predicting other critical diseases, it is believed that it would help to detect the chronic diseases at an early stage in a precise manner. In this paper, an attempt has been made to detect COPD patients and at the same time, it could distinguish the stages such as the early stage of chronic obstructive pulmonary disease patients (ESCP) and the Advanced stage of COPD patients (ASCP). We have used the Recursive Feature Elimination, Cross-Validated (RFECV) feature selection method to select features and then we consult the doctors, those are expert in the field to recommend the features among the features selected using RFECV method. The features selected using the doctor recommendation called features reduction with doctor recommendation (FRDR). After selecting two groups of features, we have used different machine learning algorithms to compare the performance of the algorithms as well as the importance of the features. It was found that the features selected using the RFECV method could able to provide accuracy of 96%, whereas the features selected with doctor recommendation name FRDR could able to provide accuracy of 90%. Although there is a difference of result in both the methods but overall, both set of features produces a good result. So, it is recommended that this approach would help distinguish different stages in real-life situations.

Background The conventional guidelines to obtain a safe proximal resection margin (PRM) of 5-6 cm during advanced gastric cancer (AGC) surgery are still applied by many surgeons across the world. Several recent studies have raised questions regarding the need for such extensive resection, but without reaching consensus. This study was designed to prove that the PRM distance does not affect the prognosis of patients who undergo gastrectomy for AGC. Aim To investigate the influence of the PRM distance on the prognosis of patients who underwent gastrectomy for AGC. Methods Electronic medical records of 1518 patients who underwent curative gastrectomy for AGC between June 2004 and December 2007 at Asan Medical Center, a tertiary care center in Korea, were reviewed retrospectively for the study. The demographics and clinicopathologic outcomes were compared between patients who underwent surgery with different PRM distances using one-way ANOVA and Fisher's exact test for continuous and categorical variables, respectively. The influence of PRM on recurrence-free survival and overall survival were analyzed using Kaplan-Meier survival analysis and Cox proportional hazard analysis. Results The median PRM distance was 4.8 cm and 3.5 cm in the distal gastrectomy (DG) and total gastrectomy (TG) groups, respectively. Patient cohorts in the DG and TG groups were subdivided into different groups according to the PRM distance; ≤ 1.0 cm, 1.1-3.0 cm, 3.1-5.0 cm and > 5.0 cm. The DG and TG groups showed no statistical difference in recurrence rate (23.5% vs 30.6% vs 24.0% vs 24.7%, P = 0.765) or local recurrence rate (5.9% vs 6.5% vs 8.4% vs 6.2%, P = 0.727) according to the distance of PRM. In both groups, Kalpan-Meier analysis showed no statistical difference in recurrence-free survival (P = 0.467 in DG group; P = 0.155 in TG group) or overall survival (P = 0.503 in DG group; P = 0.155 in TG group) according to the PRM distance. Multivariate analysis using Cox proportional hazard model revealed that in both groups, there was no significant difference in recurrence-free survival according to the PRM distance. Conclusion The distance of PRM is not a prognostic factor for patients who undergo curative gastrectomy for AGC.

Purpose Mucin 1 (MUC1) was identified as a gastric cancer (GC) susceptibility gene by genome-wide association studies in Asians and candidate gene studies in Europeans. This study aimed to investigate the association between the MUC1 rs4072037 polymorphism and GC in terms of the Lauren classification and long-term clinical outcomes. Materials and Methods A total of 803 patients with GC and 816 unrelated healthy controls were enrolled in the study. The association between the MUC1 rs4072037 variant and GC histological types and clinical outcomes, including tumor recurrence and prognosis was investigated. Results The major A allele of rs4072037 was associated with increased GC risk (P0.05). Cox proportional hazards analysis revealed the heterozygote AG rs4072037 allele as an independent risk factor influencing tumor recurrence and disease-related death in diffuse-type GC (P0.05). Conclusions The exonic single nucleotide polymorphism rs4072037 in MUC1 was associated with diffuse-type GC and was an independent risk factor influencing tumor recurrence and disease-related death in diffuse-type GC.

Conventional visible-light phototransistors based on the heterostructure of wide band gap zinc oxide (ZnO) and colloidal quantum dots (CdSe/ZnS QDs) have been studied. However, it is found that there are various deteriorated characteristics for their photoelectric behavior. Here, the phototransistors of an additional thin layer of TiO2 deposited onto the ZnO/QDs film using atomic layer deposition are developed for improving the performance of phototransistors. Small band gap QDs can absorb low-energy visible light and generate photoexcited charge carriers, which can be injected into the conduction band of wide band gap ZnO. Subsequently, the photoexcited charge carriers can be injected into the conduction band of TiO2 owing to the low injection barrier. Therefore, the ZnO/QDs phototransistor with the TiO2 layer can generate a larger photocurrent from visible light compared to a device without the TiO2 top layer. Moreover, the inorganic TiO2 layer improved the stability of the device. Under illumination with light at a wavelength of 520 nm, the maximum photosensitivity of the device was 4.2 × 106 and the transition rate was 0.728 ns−1, which is high enough to reduce the persistent photocurrent effect. This work offers a useful method to enhance the performance of visible-light phototransistors based on a heterostructure of oxide semiconductors and QDs.

Prior research has reported that the device characteristics of amorphous indium–gallium–zinc-oxide (a-IGZO) thin-film transistors (TFTs) have been changed by instabilities due to electrical stress. Because positive bias stress and high current stress produce a positive threshold voltage shift, if the digital logic circuit is designed using a-IGZO TFTs, there is a high possibility that the circuit suffers from malfunction. In this letter, the dynamic and the static logic circuits using n-type a-IGZO TFTs are compared in terms of stability for electrical stress. In order to compare the stability of the two circuits, DC and AC signals are applied. The measurement results suggest that the dynamic logic circuit is much more stable than the static logic circuit regarding electrical stress.

This paper introduces a new hole-filling method using extrapolated spatio-temporal background information to obtain a synthesized free-view. New temporal background modeling is proposed, which incorporates stationary temporal information in the hole-filling process and preserves the temporal consistency of synthesized views. A background codebook is distinguished from a non-overlapped patch-based codebook, which contributes to extracting reliable temporal background information. Furthermore, a depth-map driven spatial local background estimation is also addressed to discriminate the background holes in each disocclusion and to define two spatial BG constraints that represent the lower and upper bounds of a background candidate. Holes are filled by comparing the similarities between the temporal background information and the spatial background constraints. In addition, a depth map-based ghost removal filter is described to solve the problem of the non-fit between a color image and the corresponding depth map of a virtual view. Finally, an exemplar-based inpainting is applied to fill in the remaining holes with a priority function that includes a new depth term. The experimental results demonstrated that the proposed method led to results that promised subjective and objective improvement over state-of-the-art methods.

Summary: Background: Laparoscopic antireflux surgery is a standard surgical treatment method for gastroesophageal reflux disease (GERD) in Western countries. However, the procedure has not been actively carried out in Korea because of concerns regarding surgical complications. Here, we conducted this study to evaluate short-term surgical outcomes of laparoscopic Nissen fundoplication (LNF) performed at a single institution. Methods: From January 2010 to August 2016, totally 29 patients underwent LNF for GERD performed by three surgeons at Asan Medical Center, Korea. All patients participated in a telephonic survey including the presence of symptoms and the status of quality of life (QOL). Results: The median age at operation and BMI were 54 years and 23.8 kg/m2, respectively. Preoperatively, 27 patients (93.1%) underwent PPI therapy. All patients had typical or atypical GERD symptoms. One patient (3.4%) required reoperation because of total gastroesophageal junction obstruction. 24 patients (82.8%) reported complete or partial resolution of symptoms, whereas 21 (72.4%) reported partial or complete improvement in quality of life. In patients with reflux esophagitis, GERD symptoms were significantly relieved after LNF (P = 0.005). LNF responders tended to perceive an improvement in quality of life post operation (P

ROS(Robot Operating System) 메타운영체제는 다양한 운영체체 상에 설치하여 로봇 개발을 쉽게 하는 개발환경을 제공한다. ROS는 로봇을 구성하는 다양한 하드웨어 모듈에 대한 드라이버 프로그램들을 제공하고, 또한 로봇 동작에 필요한 다중 프로세스들 간에 TCP-IP 소켓 메시지 통신을 통해 연동할 수 있도록 한다. Ubuntu 16.04 버전의 OS에 ROS Kinetic Kame 버전을 설치해서 음성 인식된 목적지로 이동하는 서빙 이동로봇을 구현했다. 먼저 ROS에서 지원하는 SLAM(Simultaneous Localization And Mapping)에 의한 지도 작성 프로세스를 구동하여 로봇을 이동시키면서 위치 및 LiDAR 센서로 주변 장애물들에 대한 거리를 측정함으로써 지도를 작성한다. 이 지도를 토대로 ROS에서 지원하는 자율주행 프로세스를 구동하고, 음성인식에 의한 목적지를 설정하는 파이썬 프로그램에 의해 출발지로부터 목적지까지의 경로를 설정하고 Kobuki 이동체의 2개 구륜모터를 제어함으로써 목적지까지 자율주행하게 된다.

The long‐term effects of tyrosine kinase inhibitors (TKIs), including imatinib, and surgical intervention on advanced gastrointestinal stromal tumor (GIST) were evaluated. All 379 patients had metastatic or recurrent GIST and started 400 mg/d imatinib at the Asan Medical Center in periods 1 and 2 [2001‐2007 (33.2%) and 2008‐2014 (66.8%), respectively]. Men constituted 60.4%; median patient age and tumor size at the initiation of imatinib were 58.6 (14.6‐85.5) years and 51 (0‐324) mm, respectively, without differences between periods except for older age and less preimatinib surgery in period 2. Response and disease control rates with imatinib in measurable GIST were 63.1% and 94.3%, respectively, without differences between periods. More patients in period 2 underwent surgical resection for TKI‐responsive diseases within the first 2 years (24.9%, P = 0.006). With a median follow‐up of 6.1 years (2.5‐16.0) in survivors, median progression‐free survival (PFS) was 5.4 years [95% confidence interval (CI), 4.0‐6.9]. Subsequent sunitinib (P = 0.066) and regorafenib (P = 0.003) were more commonly administered in period 2. Median overall survival (OS) was 8.8 years (95% CI, 7.8‐9.7). PFS with imatinib (P = 0.002) and OS (P = 0.019) were significantly longer in period 2. Young age, smaller tumor size at the initiation of imatinib, KIT exon 11 mutation, surgical intervention, and period 2 were favorable factors for PFS and OS. Patients with advanced GIST showed better prognosis with the optimal use of imatinib, along with active surgical intervention and more common use of subsequent TKIs in period 2.

Objective: To investigate the prevalence of obesity with low muscle mass and its impact on physical function, quality of life (QOL) and pain in patients with end-stage knee osteoarthritis over 65 years old. Methods: In this cross-sectional study, we assessed a total of 562 patients. After separating the group into males and females, we divided patients into 4 further groups: normal BMI with normal muscle mass, obesity with normal muscle mass, normal BMI with low muscle mass and obesity with low muscle mass. All patients completed stair climbing test (SCT), 6-minute walk test, timed up and go test (TUG), instrumental gait analysis, Western Ontario McMaster Universities Osteoarthritis Index, VAS, and EuroQOL 5 dimensions questionnaire. Results: Obesity with low muscle mass was diagnosed in 6 males subjects (7.8%) and 9 female subjects (1.9%). Patients with obesity and low muscle mass performed the SCT-ascent and descent significantly slower than other body composition groups in both males and females. TUG in males and gait speed in females were also significantly slower in the obesity with low muscle mass group. Stepwise multiple linear regression analysis revealed that in males, obesity with low muscle mass was significantly predictive of SCT ascent (β = 0.409, p < 0.001), SCT-descent (β = 0.405, p < 0.001), and TUG (β = 0.283, p = 0.009), and in females, obesity with low muscle mass was significantly predictive of SCT-ascent (β = 0.231, p < 0.001), SCT-descent (β = 0.183, p < 0.001), and gait speed (β=-0.129, p = 0.004). Conclusions: This study confirms that the combination of obesity and low muscle mass is associated with impaired physical function in patients with end-stage knee osteoarthritis.

OBJECTIVE The aim of the study was to determine the effect of comorbidities on physical function and quality of life of patients at 3 mos after total knee arthroplasty. DESIGN Data from 140 patients who underwent a primary unilateral total knee arthroplasty were examined retrospectively. Comorbidities were osteoporosis, presarcopenia, degenerative spine disease, diabetes, and hypertension. All patients completed the following: range of motion, stair climbing test, 6-min walk test, Timed Up and Go Test, peak torque of the knee extensor and flexor, instrumental gait analysis, Western Ontario McMaster Universities Osteoarthritis Index, and EuroQoL five-dimension questionnaire. RESULTS Univariate analyses revealed that osteoporosis led to a significantly longer time to complete the stair climbing test-ascent, stair climbing test-descent, and Timed Up and Go Test and to lower scores for the 6-min walk test and peak torque of the knee extensor. Patients with degenerative spine disease showed significant negative scores for knee extension range of motion. Diabetes showed a negative correlation with peak torque of the knee extensor and knee flexion range of motion, as well as a higher Western Ontario McMaster Universities Osteoarthritis Index-stiffness score. Multivariable linear regression analysis showed that Western Ontario McMaster Universities Osteoarthritis Index-stiffness remained independently associated with diabetes. Six-minute walk test, Timed Up and Go Test, stair climbing test-ascent, and peak torque of the knee extensors showed a significant association with osteoporosis. CONCLUSIONS Comorbidities, particularly osteoporosis and diabetes, affect short-term functional outcomes 3 mos after total knee arthroplasty.

Dual-functional quantum-dots light emitting diodes (QLEDs) have been fabricated using solution processable vanadium oxide (V2O5) hole injection layer to control the carrier transport behavior. The device shows selectable functionalities of photo-detecting and light-emitting behaviors according to the different operating voltage conditions. The device emitted a bright green light at the wavelength of 536 nm, and with the maximum luminance of 31,668 cd/m2 in a forward bias of 8.6 V. Meanwhile, the device could operate as a photodetector in a reverse bias condition. The device was perfectly turned off in a reverse bias, while an increase of photocurrent was observed during the illumination of 520 nm wavelength light on the device. The interfacial electronic structure of the device prepared with different concentration V2O5 solution was measured in detail using x-ray and ultraviolet photoelectron spectroscopy. Both the highest occupied molecular orbital and the gap state levels were moved closer to the Fermi level, according to increase the concentration of V2O5 solution. The change of gap state position enables to fabricate a dual-functional QLEDs. Therefore, the device could operate both as a photodetector and as a light-emitting diode with different applied bias. The result suggests that QLEDs can be used as a photosensor and as a light-emitting diode for the future display industry.

Background Since its introduction in the early 1960s, the multiple cannulated screw fixation method has been developed for use in femoral neck fractures (FNFs); however, the parallelism of screws remains controversial. Materials and methods MEDLINE, Embase, and the Cochrane Library were systematically searched for studies published before June 2, 2020, that compared the use of parallel and non-parallel screw fixation for the treatment of FNF. The pooled analysis was designed to identify differences between the two groups and focused on postoperative complications, including fracture nonunion and osteonecrosis of the femoral head (ONFH). Results Over four studies, we enrolled 445 patients, including 195 patients with fixed FNF with parallel trajectory screws and 250 patients with fixed FNF with non-parallel screws. The pooled analysis showed no difference in the nonunion rates (odds ratio (OR) = 0.91; 95% confidence interval (CI), 0.24–3.44; p = 0.89) and no significant difference in the incidence of ONFH between parallel and non-parallel screw fixation (OR = 0.74; 95% CI: 0.21–2.63; p = 0.64). Conclusions The results of this meta-analysis reveal that screw parallelism in multiple cannulated screw fixation of FNF has no relationship with either the fracture nonunion rate or the incidence of postoperative ONFH. Level of evidence III; meta-analysis.

Purpose This study aimed to compare the surgical outcomes of total laparoscopic total gastrectomy without mesentery division (LTG without MD) and conventional total laparoscopic total gastrectomy (CLTG), as well as evaluate the appropriate method for esophagojejunostomy (EJ) reconstruction after total laparoscopic total gastrectomy (TLTG). Materials and methods We retrospectively analyzed data from 301 consecutive patients who underwent TLTG for upper or middle third gastric cancer between January 2016 and May 2019. After propensity score matching, 95 patients who underwent LTG without MD and 95 who underwent CLTG were assessed. Data on clinical characteristics and surgical outcomes, including operation time, length of postoperative hospital stay, pathological findings, and postoperative complications were analyzed. Results The LTG without MD group showed a shorter time to first flatus (3.26±0.80 vs. 3.62±0.81 days, P=0.003) and a shorter time to soft diet (2.80±2.09 vs. 3.52±2.20 days, P=0.002). The total EJ-related complications in the LTG without MD group were comparable to those in the CLTG group (9.47% vs. 3.16%, P=0.083). EJ-related leakage (6.32% vs. 3.16%, P=0.317) and EJ-related stricture (3.16% vs. 1.05%, P=0.317) rates were not significantly different between the LTG without MD and CLTG groups. No significant differences were found between the two groups in terms of other early surgical outcomes such as early complications, late complications, hospital stay, and readmission rate. Conclusions LTG without MD is a safe surgical treatment for upper or middle third gastric cancer. LTG without MD may be an alternative procedure for EJ anastomosis during TLTG.

In wireless body area networks (WBANs), the routing layer has a unique challenge that needs to be addressed by novel temperature-aware routing mechanisms to minimize the increase in body temperature. However, existing temperatureaware routing studies do not consider the compatibility with the core functions of the MAC layer for routing support, such as a two-hop star topology extension or two-hop scheduled resource allocation. The lack of interaction with the MAC layer can lead to a poor performance or inaccurate performance evaluation. To solve this problem, in this paper, we outline the key functions for routing support defined in the IEEE 802.15.6 and design the new upper-layer components required for temperature-aware routing. Subsequently, we implement a simple temperature-aware routing protocol to compare the performance with previous studies. The simulation results prove that our approach can derive a practical routing performance in terms of delay, packet delivery ratio, and power consumption, among other factors.

IEEE 802.15.6, which is the standard for wireless body area networks (WBANs), defines a unique link allocation interval called the managed access phase to meet the QoS requirements of medical applications. The hub grants an uplink allocation interval to the node according to predetermined scheduling policies; however, the IEEE 802.15.6 standard does not consider user priorities in the uplink scheduling. To address this problem, many priority-based link scheduling algorithms have been proposed; however, these algorithms ignore the unique characteristics of WBANs, such as changes in body posture and damage to body tissue, thereby leading to a waste of resources. To overcome these limitations, in this study, we propose three scheduling parameters that are suitable for WBANs, and logically determine the relationship between the proposed parameters using the multi-criteria decision making (MCDM) method. Furthermore, a priority-based dynamic link scheduling algorithm is proposed, which is based on the results of the MCDM. The simulation results prove that our proposed approach can balance the resource allocation, while maintaining the performance of high-priority nodes in terms of throughput, delay, and power consumption.

Introduction Totally laparoscopic total gastrectomy (TLTG) for advanced gastric cancer (AGC) has not been conclusively substantiated. Aim To evaluate TLTG treatment of AGC by comparing its effectiveness and surgical outcomes to those of TLTG treatment of early gastric cancer (EGC). Material and methods We performed TLTG with the (modified) overlap method for 149 gastric cancer cases between March 2012 and December 2018. We evaluated clinicopathologic characteristics, complications (including esophagojejunostomy site complications), and surgical outcomes. We also evaluated these variables in terms of their associations with EGC and AGC. Results Ninety-two males and 57 females, with a mean age of 60.7 years, were included. The mean operation time was 147.7 min. The mean number of harvested lymph nodes was 39.6. Thirteen (8.7%) patients experienced early complications, and 6 (4.0%) experienced late complications (Clavien-Dindo classification ≥ III). Eight (5.4%) patients underwent reoperation, and 8 (5.4%) were readmitted due to complications. There were no statistically significant differences in operation time, hospital stay, or surgical mortality between EGC and AGC. However, there were significant differences in early complications, late complications, rate of reoperation, and rate of readmission between EGC and AGC. Conclusions Although it has some limitations, TLTG with the (modified) overlap method for AGC treatment is feasible, safe, and associated with favorable outcomes.

Introduction Proximal gastrectomy is an alternative treatment modality for gastric cancer in the upper third of the stomach. Though several reconstruction methods have been introduced, there is no standardization. We investigated the outcomes of laparoscopic proximal gastrectomy with double tract reconstruction (LPG-DTR). Aim To investigate the outcomes of LPG-DTR. Material and methods We evaluated 37 patients who underwent curative LPG with DTR between December 2013 and December 2018. Less than half of the proximal stomach was laparoscopically resected. We performed LPG-DTR after resection. Results A total of 37 patients were included in this study, 25 (70%) of whom were male and 12 (30%) of whom were female. Overall, 31 (83.7%) patients were diagnosed with gastric cancer, 5 (13.5%) with gastrointestinal stromal tumors, and 1 (2.8%) with leiomyoma. There were 3 (9.6%) complications. However, there were no complications of grade 3 or above. We did not observe postoperative mortality or recurrence after surgery. All patients underwent postoperative endoscopic surveillance successfully. None of the patients had postoperative reflux esophagitis or stenosis. The body weight and hemoglobin levels of the patients were lowest 12 months after surgery and gradually increased thereafter. Similarly, their vitamin B12 levels were lowest 6 months after surgery. However, iron been increased after surgery until 24 months after surgery. Conclusions LPG-DTR is a favorable treatment modality for gastric cancer in the upper third of the stomach.

The aim of this work is to optimize the healthcare network for improving service delivery by allocation and deallocation of healthcare resources as per need. The extrapolation of the need for facility and resources is the most challenging part of this work which requires knowledge of the population of various geographic regions/areas. The population is also looked at from the perspective of age-group, economy, the average fraction of population requiring healthcare and also keeping in mind any history of diseases or such prone areas. Speculating the thumb rule of the healthcare worker to patient ratio i.e. 1:2808 in order to make work smooth and patient care more robust for the staff members. The proposed efforts are to help the Washington State health ministry to amend, develop and improve the staff and resources in existing facilities

In this paper, we present a new scheme to adjust Hello_timer and Neighbor_Hold_timer interval to improve the performance of routing protocol. Unlike the dynamic timer schemes, the proposed scheme decides Neighbor_Hold_timer first according to expected link duration. Subsequently, the Hello_timer is set to minimum the expected link duration among neighbor nodes. The simulation results in the AODV protocol are given to demonstrate that the packet delivery ratio, end-to-end delay and control overhead are improved rather than existing dynamic timer scheme.

Background Since its introduction in the early 1960s, the multiple cannulated screw fixation method has been developed for use in femoral neck fractures (FNFs); however, the parallelism of screws remains controversial. Materials and Methods MEDLINE, Embase, and the Cochrane Library were systematically searched for studies published before June 2, 2020, that compared the use of parallel and non-parallel screw fixation for the treatment of FNF. The pooled analysis was designed to identify differences between the two groups and focused on postoperative complications, including fracture nonunion and osteonecrosis of the femoral head (ONFH). Results Over four studies, we enrolled 445 patients, including 195 patients with fixed FNF with parallel trajectory screws and 250 patients with fixed FNF with non-parallel screws. The pooled analysis showed no difference in the nonunion rates (odds ratio (OR) = 0.91; 95 % confidence interval (CI), 0.24–3.44; P = 0.89) and no significant difference in the incidence of ONFH between parallel and non-parallel screw fixation (OR = 0.74; 95 % CI: 0.21–2.63; P = 0.64). Conclusions The results of this meta-analysis reveal that screw parallelism in multiple cannulated screw fixation of FNF has no relationship with either the fracture nonunion rate or the incidence of postoperative ONFH. Level of evidence III; meta-analysis.

Objectives The purpose of this study was to evaluate the performance of half-dose chest CT using an iterative reconstruction technique in patients with lung malignancies. Methods The Dual-source CT scans were obtained and half-dose datasets were reconstructed with 5 different strengths in 38 adults with lung malignancies. Two radiologists graded subjective image quality; noise, contrast and sharpness at the central/peripheral lung, mediastinum and chest wall of the reconstructed half-dose images, compared with those of standard-dose images, using a three-point scale. A lesion assessment; lesion conspicuity and diagnostic confidence, was also performed. The quantitative image noises; contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were measured and compared with those of standard-dose images. Results The subjective image noise in the half-dose images was less than that of the standard-dose images. The contrast in strengths 2 to 5 was superior, the sharpness of the lung parenchyma in strengths 3 to 5 was inferior, and the CNR/SNR in all strengths were higher than those of standard-dose images ( P < 0.05). The improvement of subjective image noise and contrast, the decrease in sharpness, were correlated with strength level ( P < 0.05). The lesion conspicuity in half-dose images of strengths 4 and 5 was decreased. The diagnostic confidence of the half-dose images of all strengths was comparable to that of the standard-dose images ( P < 0.05). Conclusions Half-dose chest CT images using an iterative reconstruction technique show decreased image noise, increased contrast, and diagnostic confidence comparable to standard-dose images. Images reconstructed with strength 2 and 3 appear to be the optimal choice in clinical practice.

Generally, various traffic requirements in wireless sensor network are mostly dependent on specific application types, that is, event-driven, continuous, and query-driven types. In these applications, real-time delivery is one of the important research challenges. However, due to harsh networking environment around a node, many researchers usually take different approach from conventional networks. In order to discuss and analyze the advantage or disadvantage of these approaches, some comprehensive survey literatures were published; however they are either out of date or compiled for communication protocols on single layer. Based on this deficiency, in this paper, we present the up-to-date research approaches and discuss the important features related to real-time communications in wireless sensor networks. As for grouping, we categorize the approaches into hard, soft, and firm real-time model. Furthermore, in all these categories, research has been focused on MAC and scheduling and routing according to research area or objective in second level. Finally, the article also suggests potential directions for future research in the field.

Endoscopic submucosal dissection (ESD) has become accepted as the standard treatment for early gastric cancer. However, comparative outcomes of ESD and surgery have not been evaluated for adenocarcinoma in the esophagogastric junction (EGJ). We investigated the long-term outcomes of ESD compared with those of surgery for adenocarcinoma in the EGJ. Patients who underwent ESD or surgery for Siewert type II adenocarcinoma between 2005 and 2010 and who met the absolute and expanded criteria for endoscopic resection were eligible. Clinical features and treatment outcomes were retrospectively reviewed using medical records. Of the 79 patients included, 40 underwent ESD and 39 underwent surgery. During the median follow-up period of 60.9 months (range, 13.1–125.4 months), the 5-year overall survival rates were 93.9% and 97.3% for the ESD and surgery groups, respectively (p = 0.376). There were no gastric cancer-related deaths in either group. Adverse events occurred in 11 patients (13.9%) overall, and the incidence of treatment-related adverse events was similar between the two groups (10.0% vs. 17.9%, p = 0.308). ESD may be an effective alternative to surgery for the treatment of early gastric cancer in the EGJ based on the comparable long-term outcomes.

Background: Few studies have compared early gastric cancer (EGC) outcomes according to sex and age. Methods: We retrospectively reviewed 2085 patients who underwent curative gastrectomy for EGC between 1989 and 2000. Prognosis and risk factors for nodal involvement were evaluated according to sex and age. Results: Male sex and age were independent prognostic factors for overall survival (OS) but not relapse-free survival (RFS). In young (⩽55 years) patients, there were no significant differences in RFS and OS between men and women. However, older (>55 years) men had a poorer OS and older women had a poorer RFS. Young female patients had a higher proportion of gastric cancer-related death than young male patients. Female sex was an independent risk factor for nodal involvement in younger patients. Conclusions: Young women with EGC should be more intensively treated and monitored than other patient groups and should not be treated by endoscopic resection.

To improve the packet delivery ratio in wireless sensor networks, many approaches such as multipath, opportunistic, and learning-based routing protocols have been proposed. However, the performance of the existing protocols are degraded under long-hop wireless sensor networks because the additional overhead is proportional to the number of hops. To deal with the overhead, we propose an opportunistic multipath routing that forecasts the required number of paths, as well as bifurcation based on opportunistic routing according to the reliability requirement. In the proposed scheme, an intermediate node is able to select a different node for each transmission and to handle path failure adaptively. Through a performance evaluation, we demonstrate that the proposed scheme achieves a higher packet delivery ratio and reduces the energy consumption by at least approximately 33% and up to approximately 65% compared with existing routing protocols, under the condition of an 80% link success ratio in the long-hop sensor network.

In wireless body area networks, temperature-aware routing plays an important role in preventing damage of surrounding body tissues caused by the temperature rise of the nodes. However, existing temperature-aware routing protocols tend to choose the next hop according to the temperature metric without considering transmission delay and data loss caused by human posture. To address this problem, multiple research efforts exploit different metrics such as temperature, hop count and link quality. Because their approaches are fundamentally based on simple computation through weighted factor for each metric, it is rarely feasible to obtain reasonable weight value through experiments. To solve this problem, we propose an enhanced mobility and temperature-aware routing protocol based on the multi-criteria decision making method. The proposed protocol adopts the analytical hierarchy process and simple additive weighting method to assign suitable weight factors and choose the next hop while considering multiple routing criteria. Simulation results are presented to demonstrate that the proposed protocol can efficiently improve transmission delay and data loss better than existing protocols by preventing the temperature rise on the node.

In this paper, we present a new spectrum aware routing protocol that is based on the number of available channels obtained by prediction algorithm and number of hops to reduce the end-to-end delay in cognitive radio ad hoc networks. Simulation results are given to demonstrate the shorten end-to-end delay in the aspects of mobility speed and varying number of channels.

In this paper, we present dynamic clustering scheme and hierarchical routing for Unmanned Aerial Vehicle (UAV) relayed tactical ad hoc networks. The simulation results are given to prove the higher packet deliver ratio and shorter end-to-end delay through the proposed scheme than typical routing protocol in tactical ad hoc networks.

This paper presents an efficient and stable green inverted organic light emitting diode (IOLED) using multifunctional and strong nucleophilic quality electron transport material (1,3-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (m-bPPhenB)) with silver (Ag) as an n-dopant. By the energy level alignment study using in-situ ultraviolet photoelectron spectroscopy measurement, negligible electron injection barrier between indium tin oxide (ITO) and Ag-doped m-bPPhenB (Φe ≈ 0.03 eV) is observed and the electrons can be easily tunneled from ITO into Ag-doped m-bPPhenB layer. Also, Ag dopant forms coordination bonds with phenanthroline based unit, which improves electron injection from ITO. Fabricated IOLED devices using an Ag-doped m-bPPhenB have an extremely low driving voltage of 3.6 V and external quantum efficiency of 29.0%. Such good performances of IOLED are attributed to negligible electron injection barrier at the interface between ITO and Ag-doped m-bPPhenB. The Ag-doped IOLED device also shows a good air stability owing to the stable Ag n-dopant. The doping of Ag into special electron transport layer in the IOLED structure could be applicable to various displays and lighting applications.

BACKGROUND In South Korea, which has a high incidence of gastric cancer, the most common de novo malignancy associated with liver transplantation is gastric cancer. This study sought to identify clinicopathologic characteristics in gastric cancer patients after liver transplantation, and to help manage these cases. MATERIAL AND METHODS We investigated gastric cancer patients after liver transplantation at Asan Medical Center. We analyzed sex, age, cause of liver transplantation, initiating immunosuppressant, pre-transplantation gastric fibroscopy findings, time interval between transplantation and gastric cancer occurrence, follow-up period, existence of gastric cancer screening, Helicobacter pylori infection, family cancer history, gastric cancer treatment, cancer location, size of tumor, macroscopic gross type, WHO histologic type, Lauren's classification, TNM stage, and survival. RESULTS Of 2968 adult liver transplantation patients at our hospital, 19 were diagnosed with gastric cancer. The mean age at the time of gastric cancer diagnosis was 60.2±6.8 (46-71) years and mean time interval between liver transplantation and diagnosis of gastric cancer was 56.0±30.7 (3.20-113) months. Endoscopic submucosal dissection was done for 10 patients, 4 of whom underwent surgical resection. Surgical resection as an initial treatment was done in 8 patients. One patient received chemotherapy first. The standard incidence ratio of gastric cancer in these patients was 1036 per 100 000 persons (95% CI, 623.7-1,619) in men and 318.9 per 100 000 (95% CI, 4.170-1,774) in women. CONCLUSIONS For long-term survival of liver transplant patients, early detection of de novo cancer is necessary. Therefore, annual screening for gastric cancer after liver transplantation is needed, especially in areas where the incidence of gastric cancer is high, such as South Korea.

Even though some velocity based routing protocols for (m,k)-firm stream have been recently proposed in multimedia wireless sensor networks, there are still many perspective parameters to be considered for forwarding procedure. Moreover, since they are not correlated with each other, multi-criteria system for forwarding is desirable to select next hop. However, current existing protocols apply these parameters sequentially without any prioritization. To address this issue, in this paper, we propose two (m,k)-firm specific routing protocols based on fuzzy interference system and analytical hierarchical process in conjunction with the gray relational analysis. In each protocol, delivery ratio, energy, speed, (m,k)-firm stream requirement as well as current stream status are used to select the best appropriate next hop while considering given node's constraints. Through the simulation results, we demonstrate that the proposed scheme gracefully maintains (m,k)-firm requirement while extending the network lifetime. Finally, superiority of the proposed approach to existing velocity based routing protocols is also proven through diverse simulation scenarios.

The importance of pathologic features of metastatic lymph nodes (LNs), such as size, number, and extranodal extension, has been recently emphasized in patients with papillary thyroid carcinoma (PTC). We evaluated the characteristics of metastatic LNs identified after prophylactic central neck dissection (CND) in patients with PTC. We performed a retrospective review of 1,046 patients who underwent unilateral or bilateral thyroidectomy with ipsilateral prophylactic CND. We reviewed the characteristics of the metastatic LNs and analyzed their correlation to the clinicopathologic characteristics of the primary tumor. Cervical LN metastasis after prophylactic CND was identified in 280 out of 1046 patients (26.8 %). The size of metastatic foci (≥2 mm) was independently correlated with primary tumor size (≥1 cm) (p = 0.016, OR = 1.88). Primary tumor size (≥1 cm) was also correlated to the number of metastatic LNs (≥5) (p = 0.004, OR = 3.14) and extranodal extension (p = 0.021, OR = 2.41) in univariate analysis. The size of the primary tumor affects pathologic features of subclinical LN metastasis in patients with PTC. Patients with primary tumors ≥1 cm have an increased risk of larger LN metastases (≥2 mm), an increased number of LN metastases (≥5), and a higher incidence of ENE, which should be considered in decision for prophylactic CND.

In this paper, the IES file was measured by applying a secondary optical lens to a 21 W LED engine, and the lighting calculation software RELUX was used to perform simulations with the data file of this measurement. For two-lane (two way) concrete paved roads, six LED engine are applied to each streetlight and simulation results show that Uo (uniformity) 0.56, UI (longitudinal uniformity) 0.86 and TI (threshold iIncrement) 9% which satisfies the required standards. RELUX was also used to LED streetlights by designing them in three dimensions, that is of the arm length of 2.8 m standardized by the road lighting standards of the Korea Expressway Corporation. Comparative analysis was carried out on adjustments were made in increments of 0.1 m that Uo, UI, and TI values in the range of arm lengths from 2.1 m~3.5 m. For the arm length range of 2.1 m~2.4 m, Uo was high, whereas UI was low. Therefore, we present the optimal light distribution values designed for an arm length of 2.5 m.

Oral fluoropyrimidine S-1 contains tegafur, which is metabolized to 5-fluorouracil by cytochrome P450 2A6 (CYP2A6). We here examined associations between CYP2A6 polymorphisms and treatment outcomes of adjuvant S-1 in gastric cancer patients. Patients received adjuvant S-1 (40 mg/m2 twice daily, days 1–28, every 6 weeks for eight cycles) after curative surgery for pathological stage II–III gastric cancer. We analyzed the wild-type allele (W) (CYP2A6*1) and four variant alleles (V) (CYP2A6*4, *7, *9, *10) that abolish or reduce this enzyme activity. Patients (n = 200) were enrolled between November 2007 and July 2013 with the following clinical characteristics: median age, 57 years (range, 32–83 years); 128 men, 72 women. With a median follow-up of 46.4 months, the 3-year relapse-free survival (RFS) and overall survival (OS) rates were 83.1 % (95 % CI, 77.7–88.5 %) and 94.8 % (95 % CI, 91.6–98.0 %), respectively. Genotype distributions were as follows: W/W (n = 49, 24.5 %), W/V (n = 94, 47.0 %), and V/V (n = 57, 28.5 %). Overall toxicity did not differ according to genotype for any grade (p = 0.612) or grade ≥3 (p = 0.143). However, RFS differed significantly according to CYP2A6 genotype. The 3-year RFS rates were 95.9 % for W/W, 83.1 % for W/V, and 72.5 % for V/V (p = 0.032). Carriers of W/V and V/V genotypes had a poorer RFS with a hazard ratio of 3.41 (95 % CI, 1.01–11.52; p = 0.049) and 4.03 (95 % CI, 1.16–13.93; p = 0.028), respectively, compared with the W/W genotype. CYP2A6 polymorphisms are not associated with toxicity of S-1 chemotherapy, but correlate with the efficacy of S-1 in the adjuvant setting for gastric cancer.

Clear-cell sarcoma (CCS) is a rare soft tissue sarcoma that usually develops in the lower extremities of young adults. CCS of the gastrointestinal tract is extremely rare. We report here the first case of CCS of the stomach in Korea. A 28-year-old female developed a large tumor of the stomach that was initially considered Ewing sarcoma, based on the results of a needle biopsy. She had paraneoplastic syndrome; fever, anemia, and hyperglycemia. Follow-up abdominal computed tomography after four-cycles of chemotherapy with vincristine–doxorubicin–cyclophosphamide or ifosfamide–etoposide showed no tumor shrinkage and revealed a fistula between the tumor and the gastric lumen. The infected tumor prompted debulking surgery, which resulted in improvement of her symptoms. The pathologic findings were consistent with CCS, and fluorescence in situ hybridization for EWS gene rearrangement was positive, confirming the diagnosis. This case highlights the importance of clinical suspicion for CCS in chemotherapy-refractory Ewing sarcoma. (Korean J Med 2015;89:465-469)

Various simulation studies for wireless body area networks (WBANs) based on the IEEE 802.15.6 standard have recently been carried out. However, most of these studies have applied a simplified model without using any major components specific to IEEE 802.15.6, such as connection-oriented link allocations, inter-WBAN interference mitigation, or a two-hop star topology extension. Thus, such deficiencies can lead to an inaccurate performance analysis. To solve these problems, in this study, we conducted a comprehensive review of the major components of the IEEE 802.15.6 standard and herein present modeling strategies for implementing IEEE 802.15.6 MAC on an NS-3 simulator. In addition, we configured realistic network scenarios for a performance evaluation in terms of throughput, average delay, and power consumption. The simulation results prove that our simulation system provides acceptable levels of performance for various types of medical applications, and can support the latest research topics regarding the dynamic resource allocation, inter-WBAN interference mitigation, and intra-WBAN routing.

Since the traditional geographical routing protocol and its variants use only single metric in routing process, they cannot handle with several problems such as congestion, network holes and link loss. To solve these problems, multi-metric geographical routing protocol have been proposed, however, most of them cannot adaptively change their forwarding policy according to network conditions because they fail to define the relationship or priorities between multiple metrics. To address this limitations, in this paper, we apply multi-criteria decision making (MCDM) method to the geographical routing protocol to accommodate multiple metrics in a logical way. In addition, we propose a new dynamic priority scheme to select the most suitable next hop by differentiating the priorities based on the network environment. Simulation results prove that our approach can achieve better performance than existing geographical routing protocols in the aspects of packet delivery ratio, end-to-end delay and routing overhead.

Many applications are able to obtain enriched information by employing a wireless multimedia sensor network (WMSN) in industrial environments, which consists of nodes that are capable of processing multimedia data. However, as many aspects of WMSNs still need to be refined, this remains a potential research area. An efficient application needs the ability to capture and store the latest information about an object or event, which requires real-time multimedia data to be delivered to the sink timely. Motivated to achieve this goal, we developed a new adaptive QoS routing protocol based on the (m,k)-firm model. The proposed model processes captured information by employing a multimedia stream in the (m,k)-firm format. In addition, the model includes a new adaptive real-time protocol and traffic handling scheme to transmit event information by selecting the next hop according to the flow status as well as the requirement of the (m,k)-firm model. Different from the previous approach, two level adjustment in routing protocol and traffic management are able to increase the number of successful packets within the deadline as well as path setup schemes along the previous route is able to reduce the packet loss until a new path is established. Our simulation results demonstrate that the proposed schemes are able to improve the stream dynamic success ratio and network lifetime compared to previous work by meeting the requirement of the (m,k)-firm model regardless of the amount of traffic.

In this paper, we propose a new enhanced temperature aware routing protocol to assign the temperature of node by considering current temperature and expected rise caused by the packets in the buffer. Also, two hops ahead algorithm is employed to ensure further packet forwarding to the sink. The simulation results are shown to prove that the proposed scheme is able to increase packet delivery ratio and network lifetime.

Due to high dynamics of nodes, network partitioning happens frequently in tactical ad hoc networks. To avoid this problem, relay node is one of possible solutions by connecting the partitioned networks and providing alternative backup path temporarily. Even though a vehicle and personal solider may work as relay node, unmanned aerial vehicle (UAV) is the most appropriate in the point of coverage and rapid action. However, there are some important research challenges to deploy UAV relay node such as load balancing and congestion on UAV. Thus, in the paper, we present a new routing protocol to implement UVA relay function in tactical ad hoc networks. The path via UAV relay node is controlled according to type of communications, service, and source and destination pair. The simulation results are given to prove the higher packet deliver ratio and shorter end-to-end delay through the proposed scheme than typical geographical routing protocol in tactical ad hoc networks.