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Background The clinical impact of continuing or stopping 5-aminosalicylate (5-ASA) after escalating to treatment with an anti-tumour necrosis factor (TNF) agent in patients with inflammatory bowel disease (IBD) is currently unclear. We aimed to compare the outcomes of IBD patients who stopped or continued 5-ASA after starting anti-TNF therapy. Methods We analysed data obtained from the Korean National Health Insurance claims database between 2007 and 2020. Our analysis included IBD patients already on 5-ASA treatment who started anti-TNF treatment. We compared the prognosis of patients who stopped 5-ASA within 90 days of anti-TNF initiation with those who continued 5-ASA. The primary outcome was any adverse clinical event defined as a composite of intestinal surgery, IBD-related hospitalization, or new corticosteroid use. Kaplan-Meier method and Cox proportional hazards models at landmark time were used to calculate adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). Results Among 62,262 patients diagnosed with IBD during the study period, 7,442 patients were included for analysis. A total of 1,037 (13.9%) patients discontinued 5-ASA within 90 days of starting anti-TNF therapy (Figure 1). Among the included patients, 4,479 (60.2%) had Crohn’s disease, while 2,963 (39.8%) had ulcerative colitis (Table 1). Discontinuation of 5-ASA was not associated with an increased risk of any adverse clinical events, as well as its component outcomes of intestinal surgery, IBD-related hospitalization, and corticosteroid use, with aHRs of 1.011 (95% CI, 0.934 to 1.095), 0.954 (95% CI 0.760 to 1.198), 0.995 (95% CI 0.894 to 1.107), and 0.969 (95% CI, 0.890 to 1.056), respectively (Table 2). In addition, the cumulative incidence of each adverse clinical event, as well as the composite outcome, were not significantly different between the two groups (all, p > 0.05) (Figure 2). Subgroup analysis by sex, IBD type, the timeframe of anti-TNF use, pre-anti-TNF 5-ASA use duration, pre-anti-TNF corticosteroid use, pre-anti-TNF hospitalizations, pre-anti-TNF emergency department visits, and anti-TNF agent type also showed no significant difference in the development of adverse clinical events between the two groups. Conclusion In this nationwide population-based study, we observed that discontinuing 5-ASA after starting anti-TNF therapy was not associated with an increased risk of adverse clinical events.

Background Infliximab (IFX), a monoclonal antibody approved for treating Crohn’s disease (CD), is known to show differing drug clearances in patients according to several clinical factors. However, information on the population pharmacokinetics (PKs) of intravenous (IV) IFX is lacking for Korean patients with CD. Therefore, in this study, we aimed to establish a PK model of IV IFX for this population. Methods We retrospectively analyzed data of CD patients treated with IV IFX at Asan Medical Center, a tertiary university hospital, from April 2019 to March 2022. Serum trough IFX concentration, clinical laboratory values, Crohn’s disease activity index, and demographic data were collected. NONMEM® version 7.5 was used for nonlinear mixed effects modeling. Results Of the one hundred patients included for analysis in this study, 72 were male (72.0%) (Table 1). No patient had detectable antibodies to IFX. [SJ1] A total of 823 serum IFX concentration data were collected and analyzed for fitting according to the minimization of objective function value and weighted residuals. As a result, a one-compartment population PK model with first-order elimination best described the serum trough IFX concentration measurements. Population PK estimates were 0.012 L/h for clearance (CL) (95% confidence interval: 0.012–0.013) and 6.301 L for the volume of distribution (V) (95% confidence interval: 5.932–6.671) (Table 2). Covariate analysis showed that CL and V increased as body weight increased. CL was higher in patients with low serum albumin, high serum C-reactive protein, and older age, with differing coefficients for each covariate (Figure 1). The final covariate model predicted the observed concentration-time profiles of IFX reasonably well (Figure 2). Conclusion We established a population PK model of IV IFX for CD patients in Korea. The final covariate model showed that the CL of IFX was affected by serum albumin and C-reactive protein levels, in addition to body weight and age.

Background We aimed to assess the gene expression profiles of uninflamed small bowels in patients with Crohn’s disease (CD) to identify its accompanying molecular alterations. Methods We performed RNA sequencing of the uninflamed small bowel tissues obtained from 70 patients with ileal CD, and 9 patients with colon cancer (non-CD controls) during bowel resection. Differentially expressed gene (DEG) analyses were performed using DESeq2. Gene set enrichment, correlation, and cell deconvolution analyses were applied to identify modules and functionally enriched transcriptional signatures of CD. Results A comparison of CD patients and non-CD controls revealed that of the 372 DEGs, 49 protein-coding genes and 5 lncRNAs overlapped with the IBD susceptibility loci. The pathways related to immune and inflammatory reactions were upregulated in CD, while metabolic pathways were downregulated in CD. Compared with non-CD controls, CD patients had significantly higher proportions of immune cells, including plasma cells (P=1.15×10-4), and a lower proportion of epithelial cells (P=1.12×10-4). Co-upregulated genes (M14 module) and co-downregulated genes (M9 module) were identified in CD patients. The M14 module was enriched in immune-related genes and significantly associated with the responses to anti-TNF therapy. Intestinal tissue transcriptomic analysis of 3 independent cohorts, identified M14 module upregulation in non-responders at baseline, which was predictive of response with acceptable discrimination ability (area under the curve of 77~83%). Conclusion The differences in gene expression and cellular composition between CD patients and non-CD controls imply significant molecular alterations, which are associated with the response to anti-TNF treatment.

Background Total proctocolectomy has been recommended for patients with ulcerative colitis (UC)-associated dysplasia due to the risk of its progression to colorectal cancer or metachronous recurrence. Recently, endoscopic resection has been considered as a therapeutic option for dysplasia in UC, and endoscopic submucosal dissection (ESD) has been recommended for lesions where endoscopic mucosal resection is unsuitable. We aimed to investigate the long-term outcomes of UC patients who underwent ESD for dysplasia or early colorectal cancer Methods We retrospectively reviewed 47 patients with UC-associated dysplasia/cancer referred for potential ESD to treat non-polypoid or sessile dysplasia between August 2009 and August 2022 at Asan Medical Center, a tertiary hospital in Seoul. Indications for ESD were determined according to the criteria applied for sporadic colorectal neoplasms based on magnifying endoscopy. Results The median age at UC diagnosis was 45 years, and 24 patients (51%) were male. The median duration of UC was 13 years. Colectomy was recommended for 11 patients, and the remaining 36 patients underwent ESD. The en bloc resection rate was 88.9% (32/36), and the histologic complete resection rate was 77.8% (28/36). Five patients underwent colectomy after ESD due to missed adenocarcinoma, deep submucosal cancer, and multiple dysplasia. A total of 31 patients were followed-up after ESD. Their mean (standard deviation) follow-up period was 45.9 (±30.6) months, and the mean number of post-ESD surveillance endoscopies was 3 (±2). Local recurrence of dysplasia occurred in 3 (3/31, 9.6%) patients; metachronous recurrence occurred in 7 patients (7/31, 22.6%). There were no cases of metachronous colorectal cancer. Conclusion ESD for discrete dysplastic lesions in UC patients is feasible and shows favorable outcomes in terms of colorectal cancer prevention. However, surveillance colonoscopy with short intervals is warranted due to the high metachronous recurrence rate.

Background Gut microbial dysbiosis has been suggested to contribute to pathogenesis of inflammatory bowel disease (IBD). Vedolizumab (VDZ), an α4β7 integrin blocker, has been used as an effective agent for patients with IBD. However, effect of VDZ on gut microbiome and its relationship with efficacy outcomes are still unclear. We investigated gut microbial change in patients with ulcerative colitis (UC) during VDZ treatment. Methods Patients with UC were prospectively enrolled and were given a 300 mg infusion of VDZ at weeks 0, 2, and 6 as an induction therapy and then every 8 weeks as a maintenance therapy. In cases of insufficient response, the interval of maintenance therapy was shortened to every 4 week infusion. Faecal samples were collected at weeks 0, 14, and 54 and 16S rRNA gene microbiome profiling analysis was performed. Clinical remission (CREM), clinical response (CRES), endoscopic mucosal healing (MH) and biochemical response (BioRES) were evaluated. Compositional differences in microbiome were analysed according to CREM, CRES, MH, and BioRES at weeks 0, 14, and 54. Results Faecal samples were collected from 27 patients and patients were classified according to their outcomes (Table 1). In the analyses regarding species richness (ACE, Chao1, Jackknife, The number of OTUs) and diversity indices (NPShannon, Shannon, Simpson, Phylogenetic Diversity), no significant difference was observed among groups at weeks 0, 14, and 54. There were no significant changes in microbial composition at week 14 and 54, respectively compared to basal level. However, compared to baseline, relative abundance of genus Prevotella showed significant differences between groups which achieved normalsation of C-reactive protein or not (p=0.0394) (Figure 1). In the linear discriminant analysis effect size (LEfSe) analysis, the genus Actinomyces and the species Actinomyces odontolyticus group increased in patients who had no response at efficacy outcomes (achievement of clinical remission, achievement of clinical response, achievement of endoscopic mucosal healing, normalisation of C-reactive protein, and normalisation of faecal calprotectin) at week 14, compared to week 0 (Fig 2A). The genus Clostridium_g24, the species Paraprevotella_uc and PAC001224_s were also significantly increased in the same patient group at week 54 (Fig 2B). Conclusion In UC patients treated with VDZ, microbial composition showed differences depending on the achievement of efficacy outcomes. Further studies regarding the causal relationship between microbial composition and outcomes are warranted with a larger number of patients.

Background A clinical decision support tool (CDST) has been developed and validated for predicting outcomes of vedolizumab (VDZ) therapy for patients with Crohn’s disease (CD) and ulcerative colitis (UC), respectively. We aimed to validate each CDST for predicting outcomes and need for drug optimisation in patients with inflammatory bowel disease (IBD). Methods We retrospectively analysed 166 patients with IBD (71 with CD, and 95 with UC) treated with VDZ from January 2017 through November 2021 at 6 tertiary referral centres in Korea. We assessed clinical remission (CREM) and response (CRES), corticosteroid-free clinical remission (CfCREM) and response (CfCRES), biochemical response (BioRES), endoscopic healing (EH), and need for drug optimisation by CDST-defined response groups (low vs. intermediate to high probability group with a cut-off of 13 points in CD, Table 1A, and 26 points in UC, Table 2A, respectively). CDST was evaluated by area under the receiver operating characteristics curve (AUC) and test performance. Results Patients were classified as low (27 with CD, and 28 with UC) and intermediate to high probability group (44 with CD, and 67 with UC). Among CD patients, there showed no significant difference in the response rate of any outcomes between CDST-defined groups. Among UC patients, the rates of CREM (41.0 vs. 18.5%, p=0.040) and EH (56.5 vs. 33.3%, p=0.045) at week 14 were higher among intermediate to high probability group. The rate of drug optimisation during maintenance therapy was also higher in low probability group (54.2 vs. 30.2%, p=0.038). At week 26, CDST for CD discriminated CfCREM with an AUC of 0.656 (sensitivity 87.5%, specificity 43.8%) (Table 1B). Meanwhile, CDST for UC identified CREM with an AUC of 0.606 (sensitivity 83.3%, specificity 37.9%) at week 14 (Table 2B). BioRES of FC was identified with an AUC of 0.649 (sensitivity 84.6%, specificity 45.2%) at week 26. BioRES of CRP was identified with an AUC of 0.660 (sensitivity 68.8%, specificity 63.2%) at week 26, and with an AUC of 0.642 (sensitivity 70.0%, specificity 58.3%) at week 54. Drug optimisation during maintenance therapy was identified with an AUC of 0.620 (sensitivity 54.2%, specificity 69.8%). Conclusion Both CDST for CD and UC can be used to help guide VDZ therapy for Korean patients to predict BioRES with a fair discriminant function and moderate sensitivity.

Transient cell current caused by the trapping/detrapping of grain boundary traps in the polycrystalline silicon (poly-Si) channel of a 3-D NAND cell string is comprehensively studied in this paper. This transient has a time constant of $10~\mu \text{s}$ or longer and is strongly dependent on the bias history. It is also affected by the trap distribution as revealed by TCAD simulations. Sensing offset between program verify and read results in “pseudo” charge loss/gain that reduces the sensing margin. The posttreatment of the poly-Si channel is suggested to mitigate this effect.

Background In comparison with the general population, patients with Crohn’s disease (CD) are at higher risk of developing small bowel adenocarcinoma (SBA). However, with low prevalence of SBA, data regarding the impact of CD on survival are lacking. We investigated the impact of CD on survival in patients with SBA. Methods From January 1998 through July 2021, patients with histologically confirmed SBA were retrospectively collected and classified into binary, namely, sporadic SBA and CD-associated SBA groups. Patients with duodenal SBA were excluded. The overall survival (OS) and factors associated with survival were analysed. Results Of 127 patients with SBA, 115 patients were sporadic SBA and 12 were CD-associated SBA (Table 1). Compared to patients with sporadic SBA, poorly differentiated tumour was more common among patients with CD-associated SBA (41.7 vs. 14.8%, p=0.030). Other baseline demographic characteristics including age at the diagnosis of SBA, sex, Charlson morbidity score more than 2 points, smoking history, family history of cancer, location of SBA, initial stage based on American Joint Committee on Cancer (AJCC) staging system, and treatment showed no significant difference. In survival analyses, the 1-year (yr), 2-yr, and 5-yr OS were lower in patients with CD-associated SBA, without statistical significance (1-yr OS; 81.8 vs. 90.5%, 2-yr OS; 61.4 vs. 81.7, 5-yr OS; 61.4 vs. 69.1%, p=0.590) (Fig 1). Factors associated with decreased survival were disease stage (AJCC stage IV) (hazard ratio [HR] 5.485; 95% confidence interval [CI], 2.442–12.279, p Conclusion The OS of patients with CD-associated SBA was not significantly lower than that of patients with sporadic SBA. The independent risk factors for survival were the stage of SBA and type of treatment, not Crohn’s disease.

Background We aimed to investigate the efficacy of oral beclomethasone dipropionate (BDP) as an add-on therapy to concomitant drugs and to clarify the predictive factors for response to oral BDP in Korean patients with ulcerative colitis (UC). Methods Patients with a stable concomitant drug regimen with exposure to oral BDP (5 mg/day) within 30 days before initiation were included. The partial Mayo score (pMS) was used to evaluate response to oral BDP. Clinical remission (CREM) was defined as a posttreatment pMS ≤1 point. Clinical response (CRES) was defined as an at least 2-points decrease in the posttreatment pMS and an at least 30% decrease from the baseline pMS. Patients without CREM or CRES were considered nonresponders (NRs). Results Of total 100 patients, 37 showed CREM, 19 showed CRES, and 44 were NRs (Table 1). The CREM group included more patients with mild disease activity (75.7% vs. 43.2%, P=0.011) than the NR group. In contrast to NR group, responders including CREM and CRES showed significant improvement of posttreatment ESR and CRP (ESR with P=0.001, CRP with P=0.004, respectively). Moreover, initial rectal bleeding subscore (RBS) was significantly different between CREM and CRES, or NR (both with P Conclusion Oral BDP is efficacious as an add-on therapy in Korean UC patients. In case of acute aggravation, patients with mild disease activity, especially low RBS, may be good candidates for oral BDP.

Background Data on the protective immune status against measles, mumps, rubella, varicella zoster virus (VZV), hepatitis A virus (HAV) and Epstein–Barr virus (EBV) infection among inflammatory bowel disease (IBD) patients is still lacking. Therefore, we investigated seropositivity to viral infectious diseases and associated factors in Korean IBD patients. Methods In this retrospective cohort study, serum immunoglobulin G (IgG) antibody positivity against measles virus, mumps virus, rubella virus, VZV, HAV and EBV viral capsid antigen (VCA) were measured in consecutive patients with Crohn’s disease (CD) or ulcerative colitis (UC) who first visited the IBD clinic of Asan Medical Centre, Seoul, Korea. Seropositivities and their associated factors were analysed. Results Of 263 study subjects, one hundred sixty seven (67.3%) were males. Median age at diagnosis of IBD and median age at serologic tests were 28 years (interquartile range [IQR], 20–41) and 30 years (IQR, 22–46), respectively. UC patients were 50.9% (n = 134) and median disease duration at serologic tests were 6 months (IQR, 0–59). One hundred eighty two patients (69.2%) were not under any immunosuppressive therapy. Seropositivity rates were 84.0% for measles, 85.2% for mumps and 66.5% for rubella. IgG anti-VZV positivity rates were 87.4%, but only half (50.0%) were positive for IgG anti-HAV. IgG against EBV VCA was positive in 93.6%. Younger age at IBD diagnosis ( Conclusion Seroprotection rates for common vaccine-preventable diseases and EBV among Korean IBD patients with or without immunosuppressive therapy were similar to those of the general Korean population. In the young age group under 40 years old, immunity to measles, rubella and HAV is needed to be checked together with proper vaccination as needed.

We investigate a hot-carrier injection-induced program disturb in a 3D NAND flash memory. As there exist specific coding patterns, a “down-coupling” region and a “pre-charge” regions are formed during program-verify and the following program phases, respectively, in the inhibit cell strings. A high heating field is built nearby the PGM wordline. Hot carriers may inject into the inhibit cells as Vpgm is applied. Soft ramp-down and pre-turn-on schemes are proposed to mitigate this disturb.

Herein, the synthesis of mimosa pudica leaves shaped a-iron oxide (α-Fe2O3) nanostructures is reported through simple and facile hydrothermal process. The prepared α-Fe2O3 nanostructures were characterized in terms of their morphological, structural, compositional and optical properties through a variety of characterization techniques such as FESEM, EDS, XRD, FTIR and Raman spectroscopy. The detailed characterizations revealed the well-crystallinity and dense growth of mimosa pudica leaf shaped α-Fe2O3 nanostructures. Further, the prepared nanomaterials were used as efficient electron mediator to fabricate sensitive ethanol chemical sensor. The fabricated sensor exhibited a high sensitivity of -30.37 μAmM(-1) cm(-2) and low detection limit of -0.62 μM. The observed linear dynamic range (LDR) was in the range from 10 μM-0.625 μM.

Background The Rutgeerts score (RS) is used to predict postoperative recurrence in Crohn’s disease (CD) patients after ileocolic resection primarily based on endoscopic finding at the neoterminal ileum. However, assessing anastomotic ulcers (AUs) is still a matter of debate. Our aim was to investigate the clinical significance of AUs on endoscopic recurrence in postoperative CD patients. Methods This was a single-centre retrospective study analysing postoperative CD patients with the RS of i0 to i1 at the first ileocolonoscopy within 1 year after ileocolic resection between 2000 and 2016 and those who underwent subsequent ileocolonoscopic follow-up. The study outcome was the clinical significance of AUs predicting endoscopic recurrence (RS ≥ i2b). Results Among 116 patients who were in endoscopic remission at the index postoperative ileocolonoscopy, 84.5% (98/116) underwent subsequent ileocolonoscopies. During the 30.0 months (interquartile ranges, 21.3–53.3) of median follow-up periods after the index ileocolonoscopy, 56.1% (55/98) showed endoscopic recurrence. Furthermore, 65.8% (48/73) with AUs and 75.5% (40/53) with major AUs defined as ulcer occupying ≥ 1/4 of the circumference or ≥ 3 ulcers confined to anastomotic ring, or any ulcers extended to ileocolic mucosa showed endoscopic recurrence. On multivariable analysis, the presence of AUs (adjusted hazard ratio [aHR], 4.33; 95% confidence interval [CI], 1.87–10.0; p < 0.001) and major AUs (aHR, 3.64; 95% CI, 1.95–6.79; p < 0.001) were associated with endoscopic recurrence, respectively. Conclusion AUs are associated with a significantly higher risk of endoscopic recurrence in postoperative CD patient who are in endoscopic remission.

The programme for the powder metallurgy (PM) gear rolling process to predict the densification and deformation behaviours was developed through the finite element method. The compression test was carried out to obtain the material parameters for Shima–Oyane model including six parameters with respect to yield surface and workhardening. Those parameters were employed to analyse the densification behaviour of porous material during the rolling process. The simulation results with respect to the plastic deformation and the densification behaviour of the PM gear were confirmed and verified with the experimental results.

α-Fe2O3 nanoparticles were synthesized by facile hydrothermal process at low-temperature and used as efficient anode material for the fabrication of lithium ion battery. The prepared nanoparticles were characterized in detail by various techniques such as X-ray diffraction pattern, field emission scanning electron microscopy (FESEM) combined with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) equipped with high-resolution TEM, Fourier transform infrared (FTIR) and Raman-scattering spectroscopy. The detailed characterizations revealed that the nanoparticles are synthesized in large quantity and possessing well-crystalline rhombohedral α-Fe2O3 structure. For application point of view, the synthesized nanoparticles were used as an anode material for fabrication of Li-ion battery. A coin cell of type-2032 was assembled using as-synthesized α-Fe2O3 nanoparticles and its charge-discharge profile was analyzed. Interestingly, it was observed that the cell delivered the first-charge capacity of 870 mAh g(-1) and the cell delivered a discharge capacity of 1500 mAh g(-1) during its first cycle.

This work reports a facile and large-scale synthesis of ZnO nanoparticles by simple self-propagating solution combustion method using dextrose as fuel and their effective use as a photocatalyst for photocatalytic degradation of Direct Red-23 (DR-23) dye in an immersion well type photo-reactor. The prepared ZnO nanoparticles were characterized by various analytical tools using field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy and UV-Vis. spectroscopy measurements. The detailed characterizations confirmed that the prepared ZnO nanoparticles are pure, well-crystalline and possessing wurtzite hexagonal phase. Almost complete photo-degradation of the DR-23 was observed in 110 min. under UV irradiation in presence of ZnO nanoparticle photocatalyst. This study reveals that simply prepared ZnO nanomaterials are effective photocatalyst for the photocatalytic degradation of various toxic chemicals and pollutants.

This paper reports the fabrication of highly-sensitive and selective voltammetric/amperometric cholesterol biosensor based on cholesterol oxidase co-immobilized with α -Fe 2 O 3 micro-pine shaped hierarchical structures. The α -Fe 2 O 3 micro-pine shaped hierarchical structures were synthesized by facile hydrothermal process in large quantity and characterized in detail using various techniques. The detailed studies demonstrated that the as-synthesized α -Fe 2 O 3 hierarchical structures are grown in very high density exhibiting well-crystallinity and demonstrating rhombohedral α-Fe 2 O 3 crystal structures. The fabricated cholesterol biosensors based on α -Fe 2 O 3 hierarchical structures exhibited a very high and reproducible sensitivity of 78.56 μA/mMcm 2 and detection limit (based on S/N ratio) of 0.018 mM. The biosensor exhibited a linear dynamic range from 0.1-8.0 mM and correlation coefficient of R = 0.9951. A lower value of apparent Michaelis-Menten constant ( K m app ), of 0.007 mM, exhibited a high affinity between the cholesterol and ChO x immobilized on α -Fe 2 O 3 micro-pine shaped hierarchical structures. To the best of our knowledge, this is the first report in which α -Fe 2 O 3 micro-pine shaped hierarchical structures are used for the fabrication of highly sensitive and selective cholesterol biosensor.

This paper reports the simple and facile synthesis, characterization and chemical sensing properties of iron oxide (-Fe2O3) nanoparticles. Iron oxide nanoparticles were synthesized by a simple hydrothermal process and characterized in details of their morphological, structural and compositional properties. The iron oxide nanoparticles were found to be well-crystalline and grown in very high density which were used as efficient electron mediators for the fabrication of highsensitive phenyl hydrazine sensor. The fabricated hydrazine sensor demonstrated a high sensitivity of 57.88 Am M −1 cm −2 with an experimental detection limit of 97 M. The observed linear dynamic range (LDR) for the fabricated sensor was 97 m−1.56 mM. The presented work demonstrates that iron oxide nanoparticles can be used as a potential electron mediator for the fabrication of efficient chemical sensors.

Vt instability caused by grain-boundary trap (GBT) in the poly-crystalline silicon (poly-Si) channel of a 3D NAND string are comprehensively studied. Experimental results reveal that trapping/detrapping of GBT would cause transient cell current with a time constant of 10us or longer, and this transient is strongly affected by the bias history. Sensing offset between program/erase verify (PV/EV) and read (RD) results in “pseudo” charge loss/gain that reduces the sensing margin. Modified EV, PV, or RD bias schemes are suggested to mitigate this effect.

Herein, the synthesis of mimosa pudica leaves shaped a-iron oxide (α-Fe2O3) nanostructures is reported through simple and facile hydrothermal process. The prepared α-Fe2O3 nanostructures were characterized in terms of their morphological, structural, compositional and optical properties through a variety of characterization techniques such as FESEM, EDS, XRD, FTIR and Raman spectroscopy. The detailed characterizations revealed the well-crystallinity and dense growth of mimosa pudica leaf shaped α-Fe2O3 nanostructures. Further, the prepared nanomaterials were used as efficient electron mediator to fabricate sensitive ethanol chemical sensor. The fabricated sensor exhibited a high sensitivity of -30.37 μAmM(-1) cm(-2) and low detection limit of -0.62 μM. The observed linear dynamic range (LDR) was in the range from 10 μM-0.625 μM.

Background and aims The association between inflammation and left ventricular (LV) diastolic dysfunction in continuous ambulatory peritoneal dialysis (CAPD) and non-CAPD patients is not established. The objective of this study was to test the above association and whether inflammation interacts with CAPD to increase LV diastolic dysfunction risks. Methods and results 120 subjects with normal creatinine levels and 101 CAPD patients were recruited. Echocardiographic parameters were assessed in all patients. The participants were classified as having LV diastolic dysfunction by echocardiographic findings including mitral inflow E / A ratio 220 cm/s, or decreased peak annular early diastolic velocity in tissue Doppler imaging. Blood was sampled at the baseline for measurement of inflammation markers, including tissue necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). Subjects with LV diastolic dysfunction had higher proinflammation cytokines levels in both groups. Inflamed markers correlated significantly with echocardiography parameters for LV diastolic dysfunction in patients receiving CAPD. In a multivariate regression analysis adjusting for all the factors associated with LV diastolic dysfunction, inflammation is still significantly associated with left ventricular diastolic dysfunction (TNF-alpha, OR: 2.6, 95% CI: 2.0–3.35, p p = 0.01). In addition, the interaction of CAPD and inflammation significantly contributed to the development of LV diastolic dysfunction (CAPD∗ TNF-α: OR: 1.45, 95% CI: 1.13–1.79, P = 0.004). Conclusion We found inflammation plays a vital role for LV diastolic dysfunction especially in CAPD patients. A synergistic effect between CAPD and inflammation, especially TNF-α, would further aggravate LV diastolic dysfunction.

Magnesium hydroxide (Mg(OH) 2 ) hexagonal nanodisks were synthesized via a facile microwave-assisted hydrothermal process and used, for the first time , as an efficient electron mediators for the fabrication of efficient ethanol chemical sensor. The synthesized hexagonal nanodisks were characterized in terms of their morphological and structural properties. The detailed morphological and structural investigations reveal that the synthesized Mg(OH) 2 hexagonal nanodisks are grown in high density, and possessing hexagonal crystal structure. Using as-synthesized Mg(OH) 2 hexagonal nanodisks, an efficient and robust ethanol chemical sensor has been fabricated which showed a very high and reproducible sensitivity of ∼6.89 ± 0.01 μA cm −2 mM −1 with a response time of less than 10 s, linear dynamic range from 0.1 μM to 10 mM and a correlation coefficient of R = 0.9957. The limit of detection (LOD) was estimated to be ∼73 nM. This work demonstrates that the simply synthesized Mg(OH) 2 nanostructures can effectively be used for the fabrication of efficient ethanol chemical sensors.

This paper reports a very simple, reliable and facile methodology to fabricate ultra-high sensitive liquid ammonia chemical sensor using well-crystalline hexagonal-shaped ZnO nanopencils as an efficient electron mediator. A low-temperature facile hydrothermal technique was used to synthesize ZnO nanopencils. The synthesized nanopencils were characterized in detail in terms of their morphological, structural and optical properties which confirmed that the synthesized nanomaterial is well-crystalline, possessing wurtzite hexagonal phase and possess very good optical properties. A very high sensitivity of ∼26.58 μA cm −2 mM −1 and detection limit of ∼5 nM with a correlation coefficient ( R ) of 0.9965 and a response time of less than 10 s were observed for the fabricated liquid ammonia by I – V technique. To the best of our knowledge, by comparing the literature, it is confirmed that the fabricated sensor based on ZnO nanopencils exhibits highest sensitivity and lowest detection limit for liquid ammonia. This research opens a way that simply synthesized nanomaterials could be used as efficient electron mediators for the fabrication of efficient liquid ammonia chemical sensors.

Toby died 5 October 2015. [...]

Uniform hexagonal-shaped cobalt oxide (Co3O4) nanodisks were prepared in large scale via facile aqueous solution based hydrothermal process at 110 °C. The detailed structural characterizations confirmed that the synthesized products are hexagonal cobalt oxide nanodisks, possessing very well-crystalline cubic spinel structure. A coin cell of type −2032 was assembled using the synthesized Co3O4 nanodisks and its charge–discharge profile was analyzed between the voltages 0.01 and to 2.5 V vs. Li/Li+ reference electrode. The electrochemical cell composed of Li/Co3O4 delivered an initial lithium insertion capacity of 2039 mAh/g. Although the cell exhibited high irreversible capacity during the first four cycles, the columbic efficiency has been improved upon cycling.

Well-crystalline ZnO nanowires were grown on Si(100) via non-catalytic thermal evaporation process using metallic zinc powder in presence of oxygen. The detailed morphological characterizations by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) confirmed that the synthesized products are nanowires with the typical diameter and lengths of approximately 55 +/- 5 nm and several micrometers, respectively and are grown in high density over the silicon substrate. The detailed structural characterizations by high-resolution TEM and X-ray diffraction confirmed that the synthesized nanowires are well-crystalline and possessing wurtzite hexagonal phase. The presence of Raman-active optical-phonon E2(high) mode at 437 cm(-1) in the Raman-scattering spectrum confirms good crystal quality for the as-grown ZnO nanowires. The electrical transport properties of the as-grown nanowires were explored by fabricating single nanowire based field effect transistors (FETs). The fabricated single ZnO nanowire based FET exhibits carrier concentration and electron mobility of approximately 7.49 x 10(17) cm(-3) and approximately 8.42 cm2V(-1)s(-1), respectively.

In this paper, the high-yield facile synthesis, detailed characterization and photocatalytic application of alpha-Fe2O3 nanoparticles are reported. The synthesis was done via simple hydrothermal process by using aqueous mixtures of iron chloride, hexamethylenediamine and NH3 x H2O at 110 degrees C. The morphologies of the synthesized products were examined by using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) which confirmed that the synthesized structures are almost spherical shaped nanoparticles with the average diameters of -35 +/- 5 nm, and are grown in high yield. The detailed structural characterizations and composition of the as-synthesized nanoparticles were investigated by using X-ray diffraction (XRD), high-resolution TEM (HRTEM), energy dispersive spectroscopy (EDS) attached with FESEM and Fourier transform infrared spectroscopy (FTIR) which substantiated that the as-synthesized nanoparticles are well crystalline and pure alpha-Fe2O3. The UV-Vis absorption spectrum of the synthesized nanoparticles demonstrated the existence of two optical band gaps which correspond to direct and indirect transitions, respectively. The as-synthesized alpha-Fe2O3 nanoparticles exhibit good photocatalytic properties on photocatalytic degradation of methylene blue.

Polyamide 6 (PA 6) and hydrogenated nitrile rubber (H-NBR) were blended with various blend ratios in a brabender plasticoder at 240°C/100 rpm. The processing characteristics with a mixing torque of the blends were investigated. The effect of the blend ratio on physical properties such as tensile strength, Young's modulus, elongation at break, permanent set, hardness, and swelling behavior of blends was analyzed. Most mechanical properties were found to decrease with an addition of H-NBR. The morphology of the blends was observed, and the results show a two phase system where the component with high proportions exists as a continuous phase. A cocontinuous phase was observed in blend ratios of 50/50 and 40/60. Dynamic mechanical properties were observed to study a viscoelastic property of the blends. In addition, the effect of dynamic vulcanization with peroxide on physical properties was studied, and the influence of peroxide on PA 6 was also examined. It was found that the peroxide can have an effect on PA 6 as well as act as a crosslinker to H-NBR. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Well-crystalline sulfur (S) doped ZnO nanowires have been grown via a simple thermal evaporation process on Si substrate using high purity zinc and sulfur powders in presence of oxygen. The as-grown S:ZnO nanowires were characterized in terms of their morphological structural, compositional and optical properties using several techniques such as FESEM, TEM, XRD, EDS and PL. The morphological characterizations revealed that the as-grown nanowires had diameters in the range of 60-100 nm with lengths 5-15 μm. The details structural properties confirmed the well-crystallinity and wurtzite hexagonal phase for the prepared nanowires. Room temperature photoluminescence (PL) spectrum showed a strong green band with a suppressed UV emission. The electrical properties of single S:ZnO nanowire was examined by fabricating single nanowire based field effect transistors (FETs). The detailed electrical transport results showed that S:ZnO nanowires possess n-type semiconducting behavior and exhibited an electron mobility of -67.7 cm2 V(-1) s(-1) and a carrier concentration of 2 x 10(17) cm(-3), respectively.

This paper is aimed to analyze a relationship between the temporal ASF and the temperature in Loran-C signal. Through explanations of the ground-wave propagation model and its application, the relationship between the conductivity and the temperature are explained for understanding the ASF in LORAN signal. To verifying the relationship, the experimental environment is proposed with several assumptions. The relative ASF and the temperature measurements are shown with its analysis results. Also, the temperature compensation results reflecting the analysis results are represented to verify an availability of relationship between the temporal ASF and the temperature in Loran-C signal.

We have investigated the characteristics of InGaN/GaN blue light-emitting diodes (LEDs) with a Si 6-doped GaN contact layer. The Si 6-doping of the GaN contact layer in the devices could enhance the Si doping concentration and improve the lateral conductivity in the GaN:Si contact layer without cracking. The operating voltage and dynamic resistance of LEDs with a Si b-doped GaN contact layer were 3.65 V and 27 Ω at 20 mA, respectively. The operating voltage and dynamic resistance of conventional LEDs with a uniformly doped GaN:Si contact layer were 3.94 V and 32.3 Ω at 20 mA, respectively. Also, the leakage currents at a reverse bias of -10 V were 2.8 μA for 6-doped LEDs and 29 μA for uniformly doped LEDs. However, emission properties such as electroluminescence spectra and output power were not largely affected by utilizing a δ-doped GaN:Si contact layer in the devices.

InGaN/GaN multiple-quantum-well light-emitting diode structures utilizing tunnel contact junctions have been demonstrated. The heavily doped p + /n + GaN tunnel junctions are located in the upper cladding layers of conventional devices allowing n-type GaN instead of p-type GaN as a top contact layer. Accordingly, metal Ohmic contacts are performed at the same time on the upper and the lower contact layers. The reverse-biased thin tunnel contact junction provides lateral electron current spreading along the n + layer without the use of a semi-transparent electrode and spatially uniform luminescence exhibiting an improved radiative efficiency.

In this study, the effects of axial electromagnet, variously configured multidipole permanent magnets and their combinations, on the characteristics of a square shaped (210 mm×210 mm) inductively coupled plasma source were investigated using a single electrostatic probe for Ar plasmas. The use of multidipole magnets mainly changed the uniformity of the plasma without changing the ion density of the plasma greatly. An optimized shape of the permanent magnets increased the uniformity of the plasma, and the uniformity of the ion density less than 6.0% could be obtained when measured from the center of the chamber to 10 mm before the chamber wall at 600 W of inductive power and 2 mTorr of operational pressure. The use of axial electromagnet mainly increased the ion density with the decrease of the uniformity, and ion density up to 7.5×1011 cm−3 could be obtained with 25 G at 600 W of inductive power and 5 mTorr of operational pressure. The addition of the optimized multidipole magnet to the axial electromagne...

An integrated precision inspection system has been developed for manufacturing moulds having CAD defined features. The techniques of precision measurement are implemented for CAD/CAI integration for moulds having sculptured surfaces with some basic features, such as, holes, slots and bosses. Features to be inspected are chosen in the CAD environment, and inspection planning is performed for each feature. The sampling-point strategies are: uniform distribution, curvature dependent distribution, or hybrid distribution of the two depending on the complexity of the sculptured surface. Line and plane features are divided into subintervals, and the measurement points are distributed at random positions in the subinterval. Prime number subintervals are considered for a circle feature, in order to avoid possible periodic distortion of the measurement features. The measurement path planning is performed considering collision avoidance and coordinate matching between the coordinates. The output of the planning is the machine code for a specific CMM having CNC capability. The machine code is downloaded to a specific CMM, and the measurement results are fed back to the computer. A new algorithm, called MINIMAXSURF, is developed to evaluate the form error precisely for sculptured surfaces. The algorithm considers the radius of the touch probe and evaluates the profile tolerance successfully by removing the unavoidable setup errors. The developed measurement system has been applied to real moulds, demonstrating high performance and accuracy.

Summary form only given. A large size chamber with 450 mm and plasma wall-interaction for the nano-scale feature are needed in semiconductor manufacturing industry recently. However, there are difficulties to experiment and simulate a large scale reactor chamber and nano-scale features. In the simulation case, plasma simulation using particle-in-cell (PIC) method shows very high accuracy compared with fluid simulations. However, PIC method has a disadvantage of slow speed caused by individual calculation of lots of computational particles. Recently, new computing method using graphic processing units (GPUs) enables to make a low-cost and low-power personal super computer and there is a study to utilize the GPUs for the parallelization of PIC plasma simulators [1,2]. To overcome the heavy computation problem of a PIC method, we have developed a parallelized PIC code using GPUs. In this work, two-dimensional axisymmetric simulator for a capacitively coupled plasma (CCP) sources is presented with the performance improvement using GPUs. Also, investigated were plasma phenomena with frequency variation as well as dual frequency with phase variation for CCP.

A facile aqueous solution process was used to synthesize well-crystalline ZnO nanocones at 60 degrees C by using zinc nitrate hexahydrate and sodium hydroxide. The morphological, structural and optical properties of the synthesized ZnO nanocones were investigated by using field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) equipped with high-resolution (HRTEM), X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy and UV-Vis. spectroscopy measurements. The structural and optical properties of the as-synthesized nanocones confirmed a pure and well crystalline product possessing wurtzite hexagonal phase. The as-synthesized ZnO nanocones were used as photocatalyst for the efficient photocatalytic degradation of acridine orange. The acridine orange was almost completely degraded within 105 minutes. This research demonstrates that the simply synthesized ZnO nanostructures could be efficient photocatalyst for the photocatalytic degradation of various organic dyes and chemicals.

In this paper, the high-yield facile synthesis, detailed characterization and photocatalytic application of alpha-Fe2O3 nanoparticles are reported. The synthesis was done via simple hydrothermal process by using aqueous mixtures of iron chloride, hexamethylenediamine and NH3 x H2O at 110 degrees C. The morphologies of the synthesized products were examined by using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) which confirmed that the synthesized structures are almost spherical shaped nanoparticles with the average diameters of -35 +/- 5 nm, and are grown in high yield. The detailed structural characterizations and composition of the as-synthesized nanoparticles were investigated by using X-ray diffraction (XRD), high-resolution TEM (HRTEM), energy dispersive spectroscopy (EDS) attached with FESEM and Fourier transform infrared spectroscopy (FTIR) which substantiated that the as-synthesized nanoparticles are well crystalline and pure alpha-Fe2O3. The UV-Vis absorption spectrum of the synthesized nanoparticles demonstrated the existence of two optical band gaps which correspond to direct and indirect transitions, respectively. The as-synthesized alpha-Fe2O3 nanoparticles exhibit good photocatalytic properties on photocatalytic degradation of methylene blue.

Transient receptor potential ion channel vanilloid 3 (TRPV3) is expressed in skin keratinocytes and plays an important role in thermal and chemical nociceptions in the periphery. The presence of TRPV3 inhibitors would improve our understanding of TRPV3 function and help to develop receptor-specific analgesics. However, little is known about physiological substances that specifically inhibit TRPV3 activity. Here, we investigated whether 17(R)-resolvin D1 (17R-RvD1), a naturally occurring pro-resolving lipid specifically affects TRPV3 activity.We examined the effect of 17R-RvD1 on sensory TRP channels using Ca(2+) imaging and whole cell electrophysiology experiments in a HEK cell heterologous expression system, cultured sensory neurons and keratinocytes. We also examined changes in sensory TRP agonist-specific acute licking/flicking or flinching behaviours and mechanical and thermal pain behaviours using Hargreaves, Randall-Selitto and von Frey assay systems in the absence and presence of inflammation.We showed that 17R-RvD1 specifically suppresses TRPV3-mediated activity at nanomolar and micromolar concentrations. The voltage-dependence of TRPV3 activation by camphor was shifted rightwards by 17R-RvD1, which indicates its inhibitory mechanism is as a result of a shift in voltage-dependence. Consistently, TRPV3-specific acute pain behaviours were attenuated by locally injected 17R-RvD1. Moreover, the administration of 17R-RvD1 significantly reversed the thermal hypersensitivity that occurs during an inflammatory response. Knockdown of epidermal TRPV3 blunted these antinociceptive effects of 17R-RvD1.17R-RvD1 is a novel natural inhibitory substance specific for TRPV3. The results of our behavioural studies suggest that 17R-RvD1 has acute analgesic potential via TRPV3-specific mechanisms.

As a result of the development of the plasma-assisted nano-electronics processing, there are lots of efforts that diagnose and analyze the plasma phenomena using computer simulation for the plasma sources as well as the plasma-surface interactions for the nano-scale feature. However, increasing wafer size as well as minimized feature size makes it hard to simulate the whole system. Therefore, there is a study to utilize the graphic processing units (GPUs) for the parallelization of particle-in-cell (PIC) plasma simulators [1]. PIC simulation is accurate but needs heavy calculation as it takes quite long time to calculate the dynamics and collision processes of all the computational particles. Especially, a larger size chamber with 450 mm wafer is more difficult to simulate using PIC method. Recently, heterogeneous computing, which uses graphics processing units or other device with or without CPU for computing, has gradually distributed to various computing fields including physics and fluid dynamics. In this presentation, a two-dimensional axisymmetric simulator for capacitively coupled plasma (CCP) sources is presented with the performance improvement using GPUs. The improvement of speed compared with that of single CPU calculation.