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This paper presents an overall optimization procedure and the electrical performances of 1.2 kV/10 A 4H-SiC junction barrier Schottky (JBS) diodes with high current density. To achieve high current density, the epi-layer, the design parameters for active region including p-grid width and cell pitch, and the field limiting ring for edge termination were optimized with analytic calculation to estimate forward electrical performances and with Silvaco atlas™ simulator to estimate reverse electrical performances. Based on the systematic design, the JBS diodes were fabricated and electrically characterized. The experimental results showed that the breakdown voltage (BV) of JBS diode was significantly sensitive to field limiting ring (FLR) space and that the JBS diode with the ratio of pure Schottky contact area to total active area of 0.75 and the FLR space of 1.25 μm had optimum electrical performances such as a forward current density of 370 A/cm2, a reverse leakage current below 20 μA at the reverse anode voltage of 1.2 kV, and the BV of 1400 V. These were in coincidence with the simulation results within 10% error.

A dynamic model of surface-mounted permanent magnet synchronous motors (SPMSMs) is constructed to include the dead-time disturbance voltage of the voltage-source inverter and SPMSM parameter uncertainty. The constructed model reveals that both the disturbance voltage and the parameter uncertainty degrade the SPMSM stator current control performance. Based on this notion, a nonlinear damping compensator is designed to simultaneously compensate for the dead-time disturbance voltage and parameter uncertainty in a unified structure. The designed compensator is advantageous because it is implemented with only the static feedback of available system variables with a low computational load, which enables the compensation signal to be calculated within one sampling period without requiring a specific calculation cycle. A rigorous analysis using a Lyapunov function shows that the designed compensator achieves the global exponential ultimate boundedness of the stator current errors with arbitrarily small bounds and fast decay rates in the presence of both the dead-time disturbance voltage and parameter uncertainty. The designed compensator performance is demonstrated by performing experiments using a 750-W laboratory SPMSM drive and comparing the experimental results with those of a conventional proportional-integral controller with a feedforward compensator.

Korean J Gastroenterol < Volume 76(6); 2020 < Articles Korean J Gastroenterol 2020; 76(6): 275-281 https://doi.org/10.4166/kjg.2020.160 Inflammatory Bowel Disease and Vitamin D Ki Bae Kim, Hyoung Woo Kim, Jun Su Lee, Soon Man Yoon Department of Internal Medicine, Chungbuk National University Hospital, Chungbuk National University College of Medicine, Cheongju, Korea Correspondence to: Soon Man Yoon, Department of Internal Medicine, Chungbuk National University Hospital, Chungbuk National University College of Medicine, 776 1Sunhwan-ro, Seowon-gu, Cheongju 28644, Korea. Tel: +82-43-269-7241, Fax: +82-43-269-6354, E-mail: smyoon@chungbuk.ac.kr, ORCID: https://orcid.org/0000-0003-3885-6763 Received: November 22, 2020; Revised: December 19, 2020; Accepted: December 21, 2020; Published online: December 25, 2020. © The Korean Journal of Gastroenterology. All rights reserved. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Other Sections Abstract Vitamin D contributes to bone metabolism and acts as an immune modulator for both innate and adaptive immunity. The serum level of vitamin D has been associated with inflammatory diseases, such as inflammatory bowel disease (IBD). In epidemiologic studies, IBD patients have been shown to have low levels of vitamin D. The suboptimal circulating levels of vitamin D in IBD patients may be caused by low exposure to sunlight, dietary malabsorption, and the impaired conversion of active metabolites (1,25[OH]2D). Recent studies have demonstrated that vitamin D deficiency in IBD can increase the chance of disease recurrence, IBD-related hospitalization or surgery, and deterioration of quality of life. Supplementation with vitamin D is therefore thought to reduce the risk of flare-ups and the improvement of the quality of life in IBD patients. This review aims to summarize the latest knowledge on the effects of vitamin D deficiency on IBD and the possible benefits of vitamin D supplementation in IBD patients.

The use of SiO2/4H–SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) can be problematic due to high interface state density (Dit) and low field-effect mobility (μfe). Here, we present a tetra-ethyl-ortho-silicate (TEOS)-based low-pressure chemical vapor deposition (LPCVD) method for fabricating the gate oxide of 4H–SiC MOSFETs using nitric oxide post-deposition annealing. SiO2/4H–SiC MOS capacitors and MOSFETs were fabricated using conventional wet and TEOS oxides. The measured effective oxide charge density (Qeff) and Dit of the TEOS-based LPCVD SiO2/4H–SiC MOS capacitor with nitridation were 4.27 × 1011 cm−2 and 2.99 × 1011 cm−2eV−1, respectively. We propose that the oxide breakdown field and barrier height were dependent on the effective Qeff. The measured μfe values of the SiO2/4H–SiC MOSFETs with wet and TEOS oxides after nitridation were, respectively, 11.0 and 17.8 cm2/V due to the stable nitrided interface between SiO2 and 4H–SiC. The proposed gate stack is suitable for 4H–SiC power MOSFETs.

The clinical pathway (CP) protocols simplified a systematic process from hospitalization to discharge, and were conducted to achieve standardization of the treatment process as well as improve outcomes. Thus, we investigated the optimal procedure-related hospitalization period following gastric endoscopic submucosal dissection (ESD) by comparing the rate of delayed bleeding (DB) and perforation according to CP protocols. We retrospectively enrolled 630 patients who underwent ESD for gastric dysplasia or early gastric cancer (EGC); Group A (368 patients) followed Protocol A for a hospital stay of a single night; Group B (262 patients) followed Protocol B for a hospital stay of two nights. The patient characteristics were comparable between the two groups, except for pathologic diagnosis (42.1% in Group A vs. 32.1% in Group B for EGC). DB occurred in 21 patients, and there was no significant difference in the overall DB rates between Group A (12/368 = 3.3%) and Group B (9/262 = 3.4%) (P = 0.904). The DB rates were 2.5% (8/315) and 7.5% (4/53) in Group A, and 2.7% (6/223) and 7.7% (3/39) in Group B, without and with the use of antiplatelets, respectively, and 33.3% (1/3) in Group A and 50.0% (1/2) in Group B with the use of dual antiplatelets. DB developed at various intervals post-discharge from 2 to 17 days, and was successfully controlled by endoscopic hemostasis in most cases. There were no deaths or surgeries required as a result of uncontrolled DB and no postoperative delayed perforation occurred. The CP protocols with a one-night hospitalization following gastric ESD decreased the hospital stay and did not influence postoperative complications compared to those with two-night hospitalizations.

Background Indigo naturalis is a Chinese herbal medicine that has currently been used to treat various inflammatory diseases, including ulcerative colitis. Recently, there are several reports concerning severe adverse events associated with indigo naturalis. Case presentation We described a case of a 44-year-old female with ulcerative colitis who presented with lower abdominal pain and hematochezia. She stopped taking her medicine for ulcerative colitis and started oral indigo naturalis 3 months before admission. Computed tomography showed segmental edematous wall thickening of the descending and sigmoid colon. Colonoscopy findings revealed erythema, edema, and submucosal hemorrhage, the surface of which presented a dark blue pigmentation. The histologic finding was consistent with ischemic colitis. We therefore considered an ischemic colitis induced by indigo naturalis, and the patient improved after supportive care and withdrawal of indigo naturalis. Conclusion Indigo naturalis has currently been used in the patients with ulcerative colitis as an alternative therapy. However, physicians should be aware of possible severe adverse events such as ischemic colitis.

Cell-to-cell interactions between the immune and nervous systems are increasingly recognized for their importance in health and disease. Assessment of cellular neuro-immune interactions can be aided by co-culture of two (or more) cells in an in vitro model system that preserves the morphology of neuronal cells. Here we describe methods to investigate the cytotoxic effector functions of natural killer cells on sensory neurons isolated from syngeneic embryonic and adult mice. We present methods for the morphological analysis of axon fragmentation (pruning) and dynamic cell function via live confocal calcium imaging. These techniques can easily be adapted to study interactions between other combinations of immune cell subsets and neuronal populations.

The authors propose a parameter identification method for sequential identification of electrical and mechanical parameters of surface-mounted permanent magnet synchronous motors (SPMSMs). Two normalised least mean square (NLMS) adaptive filters (AFs) are designed for identifying the electrical parameters, where the first AF identifies the stator inductance and the second AF identifies the stator resistance and rotor flux linkage. The NLMS AFs achieve faster transient responses than recursive least squares (RLS) AFs owing to lower computing load and smaller memory size. Regarding mechanical parameters, an extended sliding-mode mechanical parameter observer (ESMMPO) is employed to estimate the system disturbance and angular velocity, from which the rotational inertia, viscous damping coefficient, and load torque are identified. The rotor flux linkage identified from the second NLMS AF is used for estimating the real-time system disturbance of the ESMMPO, which enables the identification of mechanical parameters with higher accuracy. The proposed method effectively integrates the NLMS AFs and ESMMPO into a single framework to identify both electrical and mechanical parameters of the SPMSMs. The experimental results of the proposed method are compared with those of RLS AFs and the conventional ESMMPO, which demonstrates the faster response and less steady-state parameter errors of the proposed method.

The nature of ultra-wide energy bandgap (UWBG) semiconductors enables transistors to withstand large voltage swings, ensuring stable high-power and high-efficiency operation. The potential of UWBG β-Ga2O3 nano-field effect transistors (nano-FETs) has not been fully explored due to premature avalanche breakdown in these devices, despite their extremely high critical breakdown field. An exfoliated β-Ga2O3 nano-layer was fabricated into a depletion-mode nano-FET integrated with dual field-modulating layers to redistribute the electric field crowded around the drain edge of the gate electrode. A stepped-gate field-plate and a source-grounded field-modulating electrode were integrated into the planar β-Ga2O3 nano-FETs. Excellent output and transfer characteristics were demonstrated, i.e. a low subthreshold swing (95.0 mV dec−1) and high on/off ratio (∼1010), achieving an ultra-high off-state three-terminal breakdown voltage of 412 V. The experimental results were compared with numerical simulations, confirming the efficacy of the dual-field plate structure. The introduction of multiple field-modulating plates into the UWBG β-Ga2O3 nano-FETs greatly increased the voltage swings to over 400 V, suggesting the possibility for small footprint power electronics.

Using the national disability registration linked to the cancer screening database in Korea, we examined (1) trends in the gastric cancer screening rate among people with disabilities over time, and (2) whether gastric cancer screening participation and modalities differed according to presence, severity, and type of disability. We examined gastric cancer screening participation rates among individuals with registered disability, from 2006 to 2015. The age- and sex-adjusted rate for gastric cancer screening in people with disabilities increased from 25.9% in 2006 to 51.9% in 2015 (change: + 26.0%). During the same period, screening rates among people without disability improved from 24.7 to 56.5% (change: + 31.8%). Disability was associated with a screening rate [adjusted odds ratio (aOR) 0.89, 95% confidence interval (CI), 0.88–0.89]. Screening rates were markedly lower among people with severe disabilities (aOR 0.58, 95% CI 0.57–0.58) and people with autism (aOR 0.36, 95% CI 0.25–0.52), renal failure (aOR 0.39, 95% CI 0.38–0.39), brain injury (aOR 0.41, 95% CI 0.40–0.41), ostomy problems (aOR 0.53, 95% CI 0.51–0.55), intellectual disabilities (aOR 0.54, 95% CI 0.53–0.54), or mental disorders (aOR 0.55, 95% CI 0.54–0.56). The use of gastroscopy as the initial screening modality in people with disabilities was lower than in people without a disability. In spite of the availability of national gastric cancer screening program, we found significant disparities in gastric cancer screening participation, especially among people with severe disabilities and those with renal failure or brain-related/mental disabilities.

Microglia activation following peripheral nerve injury has been shown to contribute to central sensitization of the spinal cord for the development of neuropathic pain. In a recent study, we reported that the amount of nerve damage does not necessarily correlate with chronic pain development. Here we compared the response of spinal microglia, using immunohistochemistry as a surrogate of microglial activation, in mice with two different types of crush injury of the sciatic nerve. We confirmed that incomplete crush of the sciatic nerve (partial crush injury, PCI) resulted in tactile hypersensitivity after the recovery of sensory function (15 days after surgery), whereas the hypersensitivity was not observed after the complete crush (full crush injury, FCI). We observed that immunoreactivity for Iba-1, a microglial marker, was greater in the ipsilateral dorsal horn of lumbar (L4) spinal cord of mice 2 days after FCI compared to PCI, positively correlating with the intensity of crush injury. Ipsilateral Iba-1 reactivity was comparable between injuries at 7 days with a significant increase compared to the contralateral side. By day 15 after injury, ipsilateral Iba-1 immunoreactivity was much reduced compared to day 7 and was not different between the groups. Our results suggest that the magnitude of the early microgliosis is dependent on injury severity, but does not necessarily correlate with the long-term development of chronic pain-like hypersensitivity after peripheral nerve injury.

BackgroundRecent studies have found that muscle depletion may be a prognostic predictor in patients with pancreatic cancer (PC). However, in these studies, limited data were used to assess the relationship between the serial change in body composition and outcomes after PC resection. Hence, we evaluated the changes in body composition during the perioperative period in patients with PC and their association with the overall survival (OS).MethodsA total of 89 patients with PC who received surgery with curative intent between 2006 and 2015 were included in this study retrospectively. These patients underwent serial computed tomography (CT) scans: preoperatively, immediately after surgery (4 weeks), and 12 and 24 weeks after resection. The muscle and visceral fat areas were measured at the third lumbar vertebra level on cross-sectional CT images using sliceOmatic V5.0 program (TomoVision, Canada). The body composition ratio was determined by dividing the post-resection body composition at each point (4, 12, and 24 weeks) by the pre-resection body composition. Patients were divided into two groups-higher and lower groups-based on this body composition ratio (skeletal muscle mass ratio [SMR], visceral fat mass ratio [VFR]). The OS was compared between the two groups using the log-rank test.ResultsThe median age of patients was 63 (27-84) years, and the baseline body mass index was 23.0 (17.0-35.8) kg/m2. In the comparison of the SMR, there was no significant difference in the OS between the two groups at 4 and 12 weeks (4 weeks, P = 0.488; 12 weeks, P = 0.397). However, the higher group showed a longer OS than the lower group at 24 weeks (39 vs. 20 months, P = 0.008). Similarly, in the VFR, there was no significant difference in the OS between the two groups at 4 and 12 weeks (4 weeks, P = 0.732; 12 weeks, P = 0.060). However, the OS was longer in the higher group at 24 weeks (35 vs. 22 months, P = 0.023). When we analyzed the effect of muscle restoration at 24 weeks after resection on the OS by gender, there was no significant difference between the OS and SMR in the male group (P = 0.213), but a significant difference was noted in the female group (P = 0.002). In the multivariate Cox regression analysis, the SMR at 24 weeks after resection was significantly associated with the OS (P = 0.023) but not VFR at 24 weeks. In 69 patients without recurrence at 6 months, the SMR at 24 weeks was related to longer OS but without statistical significance (P = 0.07).ConclusionsThis study suggests that the restoration of muscle mass at 24 weeks after resection may be an independent prognostic factor for survival in patients with resected PC.

It remains unknown whether individuals with a family history (FH) of gastric cancer (GC) are associated with aberrant DNA methylation. The aim of this study was to investigate the association between aberrant DNA methylation and FH of GC.Using quantitative MethyLight assay, MOS, miR124a-3, NKX6-1, EMX1, CDH1, and TWIST1 methylation levels in the noncancerous gastric mucosa was compared between subjects with and without FH based on GC and Helicobacter pylori (Hp) infection. Changes in the methylation levels were evaluated over time after Hp eradication.In Hp-positive GC patients, MOS (P 0.001), CDH1 (P 0.001), and TWIST1 (P = 0.004) methylation were decreased in subjects with FH (n = 64) than in those without FH (n = 58). In Hp-positive controls, MOS methylation was lower in subjects with FH (n = 73) than in those without FH (n = 50) (P = 0.042), while miR124a-3 (P = 0.006), NKX6-1 (P 0.001), and CDH1 (P 0.001) methylation were higher in subjects with FH. CDH1 methylation constantly decreased from 2 years in GC patients and 3-4 years in controls after Hp eradication (all P 0.001). A persistent decrease in methylation over time was not observed in other genes after eradication.The methylation of MOS and CDH1 provided an association between aberrant DNA methylation and gastric carcinogenesis in FH of GC, a useful marker for GC risk in individuals with FH. Furthermore, CDH1 methylation decreased after Hp eradication.

본 논문에서는 낮은 전력 소모, 빠른 연산 능력과 다양한 입출력 장치를 지원하는 TI 사의 AM3359 MPU 기반으로 각종 센서 데이터 정보를 수집하고, 다수의 장치를 제어하며 산업용 통신이 가능한 산업용 임베디드 제어시스템을 개발한다. 개발된 산업용 제어시스템은 패스트 이더넷을 지원하여 이더넷 기반 산업용 통신이 가능하고, ADC와 DAC를 통한 아날로그 입출력뿐만 아니라 DIO를 지원하여 빠른 데이터 수집 및 처리가 가능하며 소규모 공장에서 저비용으로 효율적 운용이 가능하다. 소프트웨어 개발 환경을 TI RTOS를 기반으로 구축하고 개발된 제어시스템의 성능 평가를 위한 시험용 프로그램을 작성하고 실제 실험을 통해 개발된 제어시스템의 Modbus/TCP를 포함한 모든 입출력 장치의 동작 완료 시간이 1ms 이내로 달성되는 성능을 검증한다.

In this paper, gate drive IC for SiC power MOSFETs using soft-switching technique gate drive method is designed and implemented. Designed IC is suitable for driving silicon carbide (SiC) power MOSFET. The gate drive IC using soft-switching gate drive method, which is composed of high side and low side soft-switching controller, reduce the overshoot and switching loss of the SiC power MOSFET during the turn-on period effectively. The gate drive IC using soft-switching gate drive method reduces the switching loss by 14% without increasing the overshoot magnitude. To verify the electrical characteristics of the designed IC, simulations and experiments were performed.

The narrow voltage swing of a nanoelectronic device limits its implementations in electronic circuits. Nanolayer β-Ga2O3 has a superior breakdown field of approximately 8 MV cm−1, making it an ideal candidate for a next-generation power device nanomaterial. In this study, a field modulating plate was introduced into a β-Ga2O3 nano-field-effect transistor (nanoFET) to engineer the distribution of electric fields, wherein the off-state three-terminal breakdown voltage was reported to be 314 V. β-Ga2O3 flakes were separated from a single-crystal bulk substrate using a mechanical exfoliation method. The layout of the field modulating plate was optimized through a device simulation to effectively distribute the peak electric fields. The field-plated β-Ga2O3 nanoFETs exhibited n-type behaviors with a high output current saturation, exhibiting excellent switching characteristics with a threshold voltage of −3.8 V, a subthreshold swing of 101.3 mV dec−1, and an on/off ratio greater than 107. The β-Ga2O3 nanoFETs with a high breakdown voltage of over 300 V could pave a way for downsizing power electronic devices, enabling the economization of power systems.

Background Despite many reports on the diagnostic yield of cytology from endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), inter-slide differences are unknown. This prospective study aimed to compare diagnostic yield and cellular characteristics of bottom slides (BS) and top slides (TS) from EUS-FNA cytology performed without an on-site cytopathologist. Methods In patients with suspected pancreatic cancer on previous imaging explorations, a single endoscopist performed EUS-FNA and obtained 2 sets of cytology slide (8 BS and 8 TS), 1 cellblock slide, and 1 biopsy slide. Both slide sets were randomly assigned. A cytopathologist with more than 10 years of expertise in pancreatic cytopathology blindly inspected and compared two slide sets. Results In total, 73 specimens [42 head (57.5%), 16 body (21.9%), and 15 tail (20.5%)] were acquired for final analysis. Seventy-one cases were finally diagnosed with pancreatic cancer. The sensitivity and specificity of BS were 80.3% and 100.0%; and of TS 78.9% and 100.0%, respectively. In analyzing inter-slide difference, 66 cases (90.4%) showed consistent results between BS and TS. However, seven (9.6%) were positive only in one slide sets (4 BS and 3 TS). The proportions of specimens more than moderate and high cellularity were 75.3% and 60.3% in both slide sets (P> 0.99), and the proportion of artifact-free sets were 50.7%, and 52.1% for the BS and TS, respectively (P= 0.869). Conclusions Although BS and TS exhibited highly consistent diagnostic yields in cytologic smears from EUS-FNA, the proportion of inter-slide discordance is clinically considerable. Both slide sets need to be examined if there is no on-site cytopathologist.

OBJECTIVE Decompensated liver cirrhosis (LC) can negatively affect the outcome of endoscopic retrograde cholangiopancreatography (ERCP). We aimed to compare the efficacy and safety of ERCP in patients with clinically defined compensated and decompensated LC. METHODS In a single tertiary hospital, 146 endoscopic sphincterotomy-naive patients with LC who underwent ERCP between 2005 and 2016 were reviewed. Patients with LC who had experienced variceal bleeding, ascites or hepatic encephalopathy were included in the decompensated LC group. Cannulation, technical and clinical successes, and major post-ERCP adverse events including bleeding, pancreatitis, cholangitis and perforation were compared between the two groups. RESULTS Patients were divided into compensated and decompensated LC groups. Their baseline characteristics were not different, except for comorbid malignancy (22.3 % vs 38.5%, P = 0.038) and preprocedural transfusion (7.4% vs 36.5%, P < 0.001). The cannulation (97,9% vs 94.2%, P = 0.348) and technical (95.7% vs 88.5%, P = 0.167) success rates were not different. The clinical success rate was lower in the decompensated LC group (95.7% and 78.8%, P = 0.003), mainly due to comorbid hepatobiliary malignancy. Post-ERCP pancreatitis (6.4% vs 30.8%, P = 0.008) and cholangitis (18.1% vs 32.7%, P = 0.046) rates were higher in the decompensated LC group. CONCLUSIONS Despite lower clinical success rates due to comorbid hepatobiliary malignancy, ERCP in patients with decompensated LC is technically feasible. Because postprocedural cholangitis and pancreatitis are more frequent in patients with decompensated LC, greater procedural precautions are needed in these patients.

We report a low knee voltage and high breakdown voltage 4H-SiC TSBS employing poly-Si/Ni dual Schottky contacts. A knee voltage was significantly improved from 0.75 to 0.48 V by utilizing an alternative low work-function material of poly-Si as an anode electrode. Also, reverse breakdown voltage was successfully improved from 901 to 1154 V due to a shrunk low-work-function Schottky region by a proposed self-align etching process between poly-Si and SiC. SiC TSBS with poly-Si/Ni dual Schottky scheme is a suitable structure for high-efficiency rectification and high-voltage blocking operation.

Background/Aims: Gastric juice plays a crucial role in the physiology of the stomach. The aim of this study is to evalu ate associations among the pH of gastric juice, atrophic gastritis (AG), intestinal metaplasia (IM), pepsinogen, and Helicobacter pylori infection. Methods: Gastric biopsies and juice were collected from 46 subjects who underwent endoscopies at Seoul National University Bundang Hospital between November 2011 and March 2013. H. pylori, AG and IM were evaluated, and pepsinogen I or II, I/II ratio, and interleukin (IL)-1β levels were measured. Results: The mean pH of gastric juice was higher in the H. pylori-positive group (n=17) than that in the H. pylori-negative group (n=29) (4.54 vs 2.46, p=0.002). When patients were divided into pH

Background Studies on gut microbiota regarding colorectal carcinogenesis, including sessile serrated adenoma (SSA), have been scarce. The aim of this study is to investigate the role of mucosa-associated gut microbiota in the colorectal carcinogenesis. Methods We collected biopsy samples of normal rectal mucosa during colonoscopy from healthy control and patients with conventional adenoma, SSA, and colorectal cancer (CRC), respectively (n = 6). Pyrosequencing for 16S rRNA gene of bacteria was performed to compare gut microbiota. Results The most abundant phylum in total samples was Proteobacteria (55.6%), followed by Firmicutes (27.4%) and Bacteroidetes (11.6%). There was no significant difference in relative abundance of the phylum level among the four groups. Fusobacterium nucleatum, known to be frequently detected during colorectal carcinogenesis, was found in only one sample of patient with SSA. The rarefaction curves showed that the diversity of mucosal communities of patients with CRC is the lowest among the four groups and the diversity of mucosal communities of patients with SSA is higher than that of healthy control. Among the four groups, Shannon's and Simpson's index for diversity was the lowest and the highest in the patients with CRC, respectively; it did not reach statistical significance. The proportion of genus Pseudomonas was very high in the samples of patients with stage II-IV CRC compared with those with stage I CRC (59.3% vs. 0.3%, P = 0.064). Conclusions Our study suggests no significant role of mucosa-associated gut microbiota in the colorectal carcinogenesis. Further study for many samples or using fecal material could be helpful.

Background FOLFIRINOX has increased efficacy but also toxicity. Despite various modified FOLFIRINOX regimens, how much reduction is acceptable remains unclear. This study aimed to find the optimal relative dose intensity (RDI, %) of FOLFIRINOX that preserves tumour responses in patients with advanced pancreatic cancer (PC). Methods We reviewed 201 patients with PC treated with first-line FOLFIRINOX during 2012–2015. We established a modified Hryniuk model ( http://www.rdicalc.com ) and defined cumulative RDI (cRDI, %). The optimal cRDI thresholds for response rate (RR) and disease control rate (DCR) were assessed using receiver operating characteristic (ROC) analysis. Relationships between cRDI and haematologic toxicities (neutropenia and febrile neutropenia [FN]) were also analysed according to use of granulocyte colony-stimulating factor (G-CSF). Results Among 156 eligible patients, 133 (48 locally advanced PC and 85 metastatic PC) completed initial treatment plan prior to the first radiological evaluation (median 58 days; 71.8% cRDI). For optimal cRDI thresholds, ROC curves showed a 71.2% cRDI for RR (83.3% sensitivity, 64.7% specificity, and 0.746 area under the curve [AUC]) and a 55.3% cRDI for DCR (93.6% sensitivity, 62.5% specificity and 0.805 AUC). Among 96 patients who did not receive prophylactic G-CSF, cRDI ≥80.1% was a significant predictor for frequent FN (73.7% sensitivity, 72.7% specificity and 0.793 AUC). There was no correlation between cRDI and haematologic toxicities in patients receiving prophylactic G-CSF. Conclusion To preserve optimal RR and DCR in advanced PC, cRDI values for FOLFIRINOX >70% and >55%, respectively, are recommended. If cRDI is >80%, primary G-CSF prophylaxis is needed.

Background and Aims Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) has been proposed as an alternative management strategy for acute cholecystitis caused by malignant cystic duct obstruction in patients for whom surgery is not an option. This study aimed to compare the results of EUS-GBD with those of percutaneous transhepatic gallbladder drainage (PTGBD) for palliative management of malignant cystic duct obstruction with acute cholecystitis or symptomatic gallbladder hydrops. Methods Between November 2013 and November 2015, 14 patients with acute cholecystitis or symptomatic gallbladder hydrops as a result of malignant cystic duct obstruction underwent EUS-GBD with covered metal stents. Nineteen patients with acute cholecystitis as a result of malignant cystic duct obstruction who received PTGBD served as a control group. Patients' medical records were reviewed retrospectively. Results The technical and clinical success rates of EUS-GBD were 85.7% (12/14) and 91.7% (11/12) and of PTGBD were 100% (19/19) and 86.4% (17/19), respectively. The groups had similar adverse event rates (28.5% and 21.1%, respectively). The average duration of stent patency in patients with EUS-GBD was 130.3 ± 35.3 days, and no patient required an additional procedure before death. In 6 of 17 patients (35.3%) with clinically successful PTGBD, the catheter was not removed until the end stage of life. Conclusions EUS-GBD is a feasible, safe, and effective modality for the treatment of malignant cystic duct obstruction in patients who are not indicated for surgery. It enables improved long-term quality of life in patients with advanced-stage cancer.

A robust backstepping controller with nonlinear damping is designed for the grid-side converter (GSC) of a grid-connected doubly fed induction generator (DFIG) in wind energy conversion systems (WECSs). The designed controller achieves the exponential ultimate boundedness of both the DC-link voltage and GSC current errors with an arbitrarily fast decay rate and an arbitrarily small bound in the presence of both model uncertainties and time-varying external disturbances. A desirable feature that distinguishes the proposed controller from other existing controllers is that the control input of GSC is constructed only by the static feedback of the measurable states. As a result, the control input becomes smooth and easy to implement without requiring differentiation or switching operations. The exponential boundedness and performance of the designed controller are demonstrated by simulation using a 1.5-MW DFIG-based WECS model built in MATLAB/SimPowerSystems and compared with a standard proportional-integral controller. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.