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Welding deformation reduces the dimensional accuracy of ship hull blocks and decreases productivity due to the correction work. Prediction and minimizing of welding distortion at the design stage will lead to higher quality as well as higher productivity Therefore, the development of an effective method to predict accurately the weld distortion of hull blocks considering the fabrication sequences is required. In the case of hull block welding work in shipyards, the welding process of curved stiffened plates has large amounts of workload. This paper suggests an efficient method for predicting the welding deformation of stiffened curved plates based on the inherent strain theory combined with the finite element method. The equivalent load was determined by integrating inherent strain components which are calculated in the vicinity of heat affected zone using the highest temperature and the degree of restraint. The welding distortion of curved stiffened panels under equivalent load are calculated by elastic analysis and compared with that by intensive elasto-plastic finite element analysis. It is verified that the proposed method has a high efficiency and accuracy. [ABSTRACT FROM AUTHOR]

A long gap structure alternating current plasma display panel (ac PDP) with ignition electrodes is suggested, and its luminous characteristics are investigated. The operation voltages of the long gap structure PDP can be reduced with the help of ignition electrodes. Luminance and luminous efficacy are improved compared with those of an ac PDP with electrodes having the conventional short discharge gap. The luminance and luminous efficacy of the suggested structure can be further improved by applying address auxiliary pulses synchronized with the sustain pulses. The detailed current waveform analysis suggests that the application of address auxiliary pulse changes the discharge current ratio between the long gap electrodes to the ignition electrodes. By increasing the address auxiliary pulse voltage to a certain extent, the luminous efficacy increased along with the discharge current ratio. It has been also observed that when the width of the long gap discharge electrode is increased, the dynamic voltage margin increased accordingly. [ABSTRACT FROM AUTHOR]

The luminous efficiency characteristics of a new alternating current plasma display panel (ac PDP) structure with the segmented electrodes in delta color arrayed subpixels with enclosed barrier ribs (SDE) are investigated. The SDE structure which has a 4:3 horizontal to vertical cell dimension ratio showed higher luminance and luminous efficiency increment characteristics as the Xe partial pressure increased compared to those of the conventional stripe type with 1:3 ratio for a given resolution. The luminance and luminous efficiency increases with the electrode width, which provides a means to change the color temperature for the full color panel without using other method such as the subpixel size change. The driving feasibility of SDE structure panel with various electrode widths is confirmed by demonstrating the existence of sufficient driving voltage margin. [ABSTRACT FROM AUTHOR]

The alternating current plasma display panel (AC I)1)I'} is generally driven by the subfield method to realize the gray ,,ale, and each subfield is composed of reset, address and display period. Therefore, a significant time should be allocated to an address period in high-resolution PDP, which results in a short display period and a reduction of brightness, and so the dual scan method has been widely used to solve this problem. In this case, however the address electrodes need to be physically divided into two parts and driven by different data drive integrated circuits OCs), thereby causing a cost up due to doubling the number of data drive ICs. In this paper, we investigate the factors that could influence the address discharge time lag and, in particular, the electric field effects and priming particle effects are compared in order to achieve high speed addressing. In this regard, the address characteristics of high-Xe content panel are investigated from which it was found that the address discharge time lag was reduced to one half that of the conventional method when the priming particles are provided. [ABSTRACT FROM AUTHOR]

The mechanism of high luminous efficiency discharges with high Xe content in an ac plasma display panel was analyzed by computer simulation using a two-dimensional fluid model. The model has reproduced well the experimental results. The high luminous efficiency with high Xe content is attributed to high electron heating efficiency as well as high excitation efficiency by electron. The electron heating efficiency is increased with increasing the sustaining voltage under high Xe content and this phenomenon was analyzed by investigating the cathode sheath and secondary electron emission characteristics. [ABSTRACT FROM AUTHOR]

A 51-year-old highly fit man presented for dyspnea with strenuous aerobic exercise. The patient was asymptomatic and all tests were normal at rest. With increasing exercise intensity, he suddenly complained of dyspnea and showed a severe exercise-induced hypoxemia with an excessive alveolar-arterial oxygen tension difference. In agitated saline contrast echocardiography at peak exercise, a large amount of left to right shunt was identified after > 5 cardiac cycles, which suggests the presence of exercise-induced intrapulmonary arteriovenous shunt in this patient. [ABSTRACT FROM AUTHOR]

Background/Aims Helicobacter pylori infection may be associated with extra-digestive diseases such as coronary artery disease, nonalcoholic fatty liver disease and autoimmune disease. Many studies used serological tests to diagnose of H. pylori infection, but these methods detected past and current infection. The aim of this study was to determine the correlation between current infection of H. pylori and autoimmune thyroid disease. Methods A retrospective, cross-sectional study was conducted with those who received screening esophagogastroduodenoscopy between January 1, 2010 and December 31, 2018. The subjects were categorized into two groups that were H. pylori infected group and no H. pylori infected group. Anti-thyroid peroxidase (anti-TPO) antibody was compared as the primary outcome between two groups. Also, thyroid-stimulating hormone, free thyroxine, rheumatoid factor (RF) levels and thyroid function were compared. Results A total of 43,321 subjects were included in the analysis. The number of H. pylori positive subjects was 15,927 and H. pylori negative was 27,394. Anti-TPO antibodies positive rate of H. pylori positive group was 8.27% (n=1,317) and H. pylori negative group was 9.47% (n=2,595) in the univariate analysis (p<0.0001). In the multivariate analysis, the positive rate of anti-TPO antibody in the H. pylori positive group was significantly lower (odds ratio, 0.877; 95% confidence limits, 0.818 to 0.941; Pr >chi-square 0.0002) than in the H. pylori negative group and RF positive rate in the H. pylori positive group was significantly lower (odds ratio, 0.898; 95% confidence limits, 0.74 to 0.86; Pr >chi-square <0.0001) than in the H. pylori negative group when age, sex and body mass index were adjusted as covariates. Conclusions Current H. pylori infection had a statistically significant effect on the positive rate of anti-TPO antibody and RF inversely. [ABSTRACT FROM AUTHOR]

Background/Aims Proton-pump inhibitor (PPI) use alters small intestinal bacterial overgrowth and may induce increased portal endotoxins and increase the risk of fatty liver disease, but the association of PPI use with the risk of fatty liver disease has been controversial. Therefore, we evaluated the prospective association between PPI use and the incidence of fatty liver. Methods Cohort study conducted using the Korean National Health Insurance Service-National Sample Cohort, a nationwide population-based representative sample followed-up from January 1, 2003 to December 31, 2013. PPI use was identified from treatment claims and considered as a time-varying variable. Incident fatty liver disease was identified from outpatient visit claims (ICD-10 diagnosis codes K76.0 or K70.0). Results The age-, sex-, body mass index, residential area-, and income percentiles-adjusted hazard ratio (HR) for incident cholangitis comparing use versus no use of PPI was 1.41 (95% confidence interval [CI], 1.33 to 1.49). The association persisted after further adjustment for smoking, alcohol habit, Charlson comorbidity index score, and year of screening exam (HR, 1.35; 95% CI, 1.28 to 1.43). Conclusions In this large cohort, PPI use was associated with an increased risk of fatty liver. Physicians prescribe PPI should consider fatty liver as a potential complication of PPI use. [ABSTRACT FROM AUTHOR]

Background/Aims Obesity is an established risk factor of erosive esophagitis and metabolic unhealthiness has been implicated in the pathogenesis of erosive esophagitis. Yet, the risk of erosive esophagitis among obese individuals without obesity-related metabolic unhealthiness, a condition referred to as metabolically healthy obese (MHO), remains unclear. We examined the association between body mass index (BMI) categories and the development of erosive esophagitis in a cohort of metabolically healthy individuals. Methods We conducted a cohort study of 14,725 asymptomatic adults free of erosive esophagitis and metabolic abnormalities, who underwent repeated health check-ups including screening endoscopy. A metabolically healthy state was defined as having no metabolic syndrome components and a homeostasis model assessment of insulin resistance <2.5. The presence of erosive esophagitis was determined using endoscopy. Results During 81,385.2 person-years of follow-up, 1,865 participants developed erosive esophagitis (incidence rate, 22.9 per 1,000 person-years). The multivariable adjusted hazard ratios (95% confidence intervals) for incident erosive esophagitis comparing overweight (BMI, 23.0-24.9 kg/m2) and obese (≥25 kg/m2) with normal-weight participants (18.5-22.9 kg/m2) were 1.12 (1.00-1.25 kg/m2) and 1.29 (1.14-1.47 kg/m2), respectively. In dose-response analyses, increasing BMI also showed positive association with overall and LA-B grade or higher. The association persisted in MHO individuals without central obesity. The association between waist circumference categories and the development of erosive esophagitis was also evident. Conclusions In a large cohort of strictly defined metabolically healthy men and women, the MHO phenotype was associated with an increased incidence of erosive esophagitis, providing evidence that the MHO phenotype is not protective from gastroesophageal reflux disease. [ABSTRACT FROM AUTHOR]

Background/Aims Previous studies have suggested a link between Helicobacter pylori infection and dyslipidemia, yet large-scale longitudinal studies have not elucidated this association. Therefore, we assessed the longitudinal effects of both H. pylori infection and eradication on lipid profiles in a large cohort of asymptomatic men and women. Methods This cohort study included 18,621 adults without dyslipidemia at baseline, who participated in a repeated, regular health screening examination, which included upper gastrointestinal endoscopy, between January 2009 and December 2018. The primary outcome was incident dyslipidemia at follow-up. Results During the 52,992 person-years follow-up, participants with persistent H. pylori infection had a higher incidence rate (177 per 1,000 person-years) of dyslipidemia than those whose infections had been successfully eradicated (158.2 per 1,000 person-years) and those who were uninfected (157.6 per 1,000 person-years). In a multivariable model adjusted for age, sex, body mass index, smoking status, alcohol intake, and baseline levels of low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and triglyceride, the H. pylori eradication group was associated with a lower risk of dyslipidemia than the persistent group (hazard ratio, 0.89; 95% confidence interval, 0.82 to 0.96; p=0.005). The risk of dyslipidemia in the eradication group was similar to that of participants uninfected with H. pylori (p=0.245). Conclusions Persistent H. pylori infection was significantly associated with the risk of dyslipidemia. H. pylori infection may play a pathophysiologic role in the development of dyslipidemia and H. pylori eradication might decrease the risk of dyslipidemia. [ABSTRACT FROM AUTHOR]

Background/Aims The advancement of therapeutic agent has made it possible to achieve endoscopic remission in inflammatory bowel disease. Consequently, the treatment goal of ulcerative colitis (UC) also has been changed to achieve endoscopic remission (ER). However, there was insufficient clinical evidence to whether a step-up treatment should be performed to achieve ER in clinical remission (CR) without ER. And there is inadequate data on the need to consider the distribution and severity of residual inflammation in UC. This retrospective study aimed to evaluate the prognostic significance (such as step-up therapy, hospitalization, and colectomy) of the distribution and severity of residual inflammation in UC patients with CR. Methods A total of 134 UC patients who underwent endoscopic evaluation in CR and underwent colonoscopy more than three times between January 2000 and December 2018 were retrospectively reviewed. Patients were allocated by endoscopic healing state and distribution of inflammation to an ER (n=33, 24.6%), patch distribution (n=17, 12.7%) or rectal involvement (n=84, 62.7%). We reviewed patient's characteristics, endoscopic findings and ascertain poor outcome-free survival (PFS) until June 2019. Results In UC patient with CR, the PFS was significantly better in ER and patch distribution (p=0.003). ER and patch distribution had similar PFS (p=0.683). The baseline clinical characteristics of the patch distribution and rectal involvement were not significantly different except for the pattern of residual inflammation (p<0.001). Multivariable analysis showed that ER and patch distribution was a good prognostic factor of PFS for UC with CR (hazard ratio, 0.11; p=0.035). Conclusions There was no statistically significant difference in the PFS between ER and patch distribution in the CR state of UC patients. Therefore, we propose selective escalation of treatment modality in CR patients, even if they do not reach ER. [ABSTRACT FROM AUTHOR]

Oral lichen planus (OLP) is a chronic inflammatory disease that is characterized by the infiltration of T cells into the oral mucosa, causing the apoptosis of basal keratinocytes. OLP is a multifactorial disease of unknown etiology and is not solely caused by the malfunction of a single key gene but rather by various intracellular and extracellular factors. Non-coding RNAs play a critical role in immunological homeostasis and inflammatory response and are found in all cell types and bodily fluids, and their expression is closely regulated to preserve normal physiologies. The dysregulation of non-coding RNAs may be highly implicated in the onset and progression of diverse inflammatory disorders, including OLP. This narrative review summarizes the role of non-coding RNAs in molecular and cellular changes in the oral epithelium during OLP pathogenesis.

Abstract Background Prediction of difficult airway is critical in the airway management of trauma patients. A LEMON method which consists of following assessments; Look-Evaluate-Mallampati-Obstruction-Neck mobility is a fast and easy technique to evaluate patients’ airways in the emergency situation. And a modified LEMON method, which excludes the Mallampati classification from the original LEMON score, also can be used clinically. We investigated the relationship between modified LEMON score and intubation difficulty score in adult trauma patients undergoing emergency surgery. Methods We retrospectively reviewed electronic medical records of 114 adult trauma patients who underwent emergency surgery under general anesthesia. All patients’ airways were evaluated according to the modified LEMON method before anesthesia induction and after tracheal intubation; the intubating doctor self-reported the intubation difficulty scale (IDS) score. A difficult intubation group was defined as patients who had IDS scores > 5. Results The modified LEMON score was significantly correlated with the IDS score (P

Glioblastoma is an actively growing and aggressive brain tumor with a high propensity of recurrence. Although the surgical removal of tumor mass is the primary therapeutic option against glioblastoma, supportive pharmacotherapy is highly essential due to incredibly infiltrative characteristic of glioblastoma. Temozolomide, an FDA-approved alkylating agent, has been used as a first-line standard pharmacological approach, but several evident limitations were repeatedly reported. Despite additional therapeutic options suggested, there are no medications that successfully prevent a recurrence of glioblastoma and increase the five-year survival rate. In this study, we tested the possibility that finasteride has the potential to be developed as an anti-glioblastoma drug. Finasteride, an FDA-approved medication for the treatment of benign prostate hyperplasia and androgenic alopecia, is already known to pass through the blood–brain barrier and possess antiproliferative activity of prostate epithelial cells. We showed that finasteride inhibited the maintenance of glioma stem-like cells and repressed the proliferation of glioblastoma. Mechanistically, finasteride lowered intracellular ROS level by upregulating antioxidant genes, which contributed to inefficient β-catenin accumulation. Downregulated β-catenin resulted in the reduction in stemness and cell growth in glioblastoma.

The discovery of novel and critical genes implicated in malignant development is a topic of high interest in cancer research. Intriguingly, a group of genes named “double-agent” genes were reported to have both oncogenic and tumor-suppressive functions. To date, less than 100 “double-agent” genes have been documented. Fubp1 is a master transcriptional regulator of a subset of genes by interacting with a far upstream element (FUSE). Mounting evidence has collectively demonstrated both the oncogenic and tumor suppressive roles of Fubp1 and the debate regarding its roles in tumorigenesis has been around for several years. Therefore, the detailed molecular mechanisms of Fubp1 need to be determined in each context. In the present study, we showed that the Fubp1 protein level was enriched in the S phase and we identified that Fubp1 deficiency altered cell cycle progression, especially in the S phase, by downregulating the mRNA expression levels of Ccna genes encoding cyclin A. Although this Fubp1-cyclin A axis appears to exist in several types of tumors, Fubp1 showed heterogeneous expression patterns among various cancer tissues, suggesting it exhibits multiple and complicated functions in cancer development. In addition, we showed that Fubp1 deficiency confers survival advantages to cells against metabolic stress and anti-cancer drugs, suggesting that Fubp1 may play both positive and negative roles in malignant development.

In the present study, external restraints imposed normal to the plate during the cooling stage were determined to be effective for reduction of the angular distortion of butt-welded or fillet-welded plate. A welding analysis model under external force during the cooling stage was idealized as a prismatic member subjected to pure bending. The external restraint was represented by vertical force on both sides of the work piece and bending stress forms in the transverse direction. The additional bending stress distribution across the plate thickness was reflected in the improved inherent strain model, and a set of inherent strain charts with different levels of bending stress were newly calculated. From an elastic linear FE analysis using the inherent strain values taken from the chart and comparing them with those from a 3D thermal elasto-plastic FE analysis, welding deformation can be calculated.

In the present study, the existing equivalent stain method is improved to make up for its weaknesses. The improved inherent strain model is built considering more sophisticated three dimensional constraints which are embodied by six cubic elements attached on three sides of a core cubic element. From a few case studies, it is found that the inherent strain is mainly affected by the changes in restraints induced by changes of temperature-dependent material properties of the restraining elements. On the other hand, the degree of restraints is identified to be little influential to the inherent strain. Thus, the effect of temperature gradients over plate thickness and plate transverse direction normal to welding is reflected in the calculation of the inherent strain chart. The welding deformation can be calculated by an elastic FE analysis using the inherent strain values taken from the inherent strain chart.

Neural stem cells (NSCs) are undifferentiated, multi-potent cells that can give rise to functional neurons and glial cells. The disruption in NSC homeostasis and/or the impaired neurogenesis lead to diverse neurological diseases, including depression, dementia, and neurodegenerative disorders. Falcarindiol (FAD) is a polyacetylene found in many plants, and FAD shows the cytotoxicity against breast cancers and colon cancers. However, there is no research on the consequence of FAD treatment in normal stem cells. Here, we suggest that FAD has anticancer roles against glioblastoma cells by inducing the differentiation of glioblastoma stem-like cells, as well as activating apoptosis pathway in glioblastoma cells. On the other hand, we also show that FAD has detrimental effects by disrupting the maintenance of normal NSCs and altering the balance between self-renewal and differentiation of NSCs.