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Many commercial optical glasses exhibit thermorheologically simple behavior, which allows the application of the time-temperature superposition principle within the temperature range from the glass transition temperature (Tg) to the deformation point (At). However, the molding temperature is set above At in cases involving significant deformation during glass molding press, such as with large-aperture concave meniscus lenses. Additionally, stress relaxation is observed in optical glasses even at temperatures below Tg. Nevertheless, the applicability of the time-temperature superposition principle to optical glasses within the temperature range below Tg and above At has not been thoroughly investigated. Therefore, in this study, uniaxial compression creep tests were conducted over a wide temperature range from approximately Tg - 20 °C to At + 50 °C using three types of commercial optical glasses to evaluate their thermo-viscoelastic properties. The results revealed that when the creep functions at each test temperature were shifted along a logarithmic time axis, they formed a smooth single curve (master curve), indicating the applicability of the time-temperature superposition principle. Moreover, while the shift factors for all glasses exhibited Arrhenius behavior within the temperature range of Tg to At, in two types of glasses, they exhibited a curved change below Tg and above At. Therefore, applying the Williams–Landel–Ferry (WLF) equation to approximate these shift factors revealed that they could be well approximated across the entire test temperature range. However, when applying the WLF equation to optical glass, limiting the temperature to a range higher than Tg - 30 °C was necessary. To express the shift factor over a wide temperature range of several hundred degree Celsius, from room temperature to molding temperature, it was practical to use the multi-linear Narayanaswamy equation, in which the apparent activation energies vary near At.

Abstract Background Previous studies have revealed an association between probiotic use and effectiveness of immune checkpoint inhibitors in renal and lung cancers. However, little is known regarding other cancers, including gastrointestinal cancer. Methods To address this issue, we conducted a multicenter retrospective cohort study and the duration of nivolumab treatment for various cancers was compared between probiotic users and non‐users. Results and Conclusions In total, 488 patients who received nivolumab therapy were included. In all cancers, no significant differences in treatment duration of nivolumab were observed between probiotic users and non‐users (median 62.0 vs. 56.0, hazard ratio = 1.02, p = 0.825), whereas probiotic use, compared with non‐use, in patients with gastric cancer was significantly associated with a longer duration of nivolumab treatment (55.0 vs. 31.0 days, hazard ratio = 0.69, p = 0.039). In conclusion, probiotics may improve the response to nivolumab and potentially prolong progression‐free survival in patients with gastric cancer.

Progressive damage behavior of woven composite structure is simulated, based on decoupled multi-scale damage analysis to consider microscopic woven structure. Since woven composites have complex microstructure, it is difficult to predict their damage behavior by only experimental approaches. Evaluating damage process is important for the assessment of safety, and numerical method of simulating damage behavior is demanded. In this paper, decoupled multi-scale analysis method was adopted. The constitutive law used in analysis of structural member scale (macroscopic scale) was identified by analysis of weave-structure scale (microscopic scale) and two-scale simultaneous analyses are no longer necessary. In microscopic scale, representative unit cell (RUC) of woven structure was considered, and in-plane periodicity was assumed to reflect inhomogeneity caused by woven structure. Microscopic analysis was carried out to identify the constitutive law which is used in the macroscopic analysis. Transverse crack of fiber bundle was modeled using enhanced continuum damage mechanics (ECDM) model. Fiber/matrix interface debonding was also modeled by cohesive zone model (CZM). In the macroscopic scale, structural member was modeled. Macroscopic analysis was carried out to investigate initial damage occurrence location and damage process. Damage progress was modeled by stiffness degradation, using CDM model and microscopic analysis results were reflected to determination of macroscopic damage variables. Four-point bending test of macroscopic specimen was carried out for validation of the analysis. Damage observation showed the macroscopic analysis effectively simulated damage occurrence and propagation. Localization analysis was then carried out to investigate damage behavior of woven structure, reflecting deformation history of macroscopic initial damage occurrence location to microscopic analysis. By comparing the analysis to cross-section observation, initial damage simulation showed good agreements with experiment.

Osimertinib administration has been approved as an adjuvant treatment after complete surgical resection in patients with EGFR-mutated NSCLC. This article presents the first report of life-threatening postoperative osimertinib-induced interstitial lung disease. An 83-year-old male patient underwent right upper lobectomy (pathologic stage IIA) and osimertinib (80 mg/d) was initiated on postoperative day 75. On day 44 of osimertinib administration, chest computed tomography revealed diffuse ground-glass opacities; accordingly, osimertinib-induced interstitial lung disease was diagnosed. Steroid pulse therapy was initiated using a high-flow nasal cannula to treat dyspnea and hypoxemia, rapidly improving the respiratory status and imaging findings; moreover, the patient’s clinical course was excellent. This case report suggests that the postoperative occurrence of severe osimertinib-induced interstitial lung disease is a crucial factor that must be considered in patient decision-making regarding perioperative treatment.

In this study, finite element analyses are conducted for the glass molding press of a large-diameter concave meniscus lens. As press molding may commence in a non-uniform temperature field, thermal-structure two-way coupling simulations are applied to the molding process to understand the sequential changes in the lens shape and temperature distribution. Three types of glass preform, namely, ball model, approximate curvature model, and near net model, are prepared to investigate the effects of preform shape on formability and internal stress. Preforms with a small clearance (shape difference) from the mold shape require less time for complete transfer; however, high internal stresses occur during cooling. The internal stress generated during cooling is thermal stress, caused by the internal temperature difference; it can be reduced by expanding the contact regions between the lens surfaces and molds. Moreover, to improve formability and reduce internal stress when forming using an approximate curvature model, the preform shape and heat input temperature conditions to the upper and lower molds are optimized. In both cases, although the internal stress is slightly higher during the molding process, the entire lens surface is in contact with the mold during cooling, thus resulting in a significant decrease in internal stress.

Key Clinical Message A female in her thirties inserted an Asian traditional hair stick, kanzashi, into her urinary bladder for sexual gratification. We need to know that everyday objects can become bladder foreign bodies and how to manage them properly.

Introduction The COVID‐19 pandemic has been causing delay in patient arrival at hospital and starting surgery. We report a delay in a case of testicular torsion complicated by acute pneumonia during the COVID‐19 pandemic in Japan. Case presentation A 17‐year‐old Japanese boy presented to our emergency room with acute left scrotum pain and fever in January 2021. It took 2.5 h to transfer him. Physical examination and color Doppler ultrasonography revealed left testicular torsion. Chest computed tomography indicated acute pneumonia. He successfully underwent surgical detorsion 7.5 h after symptom onset, with COVID‐19 preventive measures in place. A negative polymerase chain reaction test result for COVID‐19 was revealed after surgery. Conclusion We experienced a rare case of testicular torsion complicated by acute pneumonia during the COVID‐19 pandemic. Special attention should be paid to preventing infection and surgery delay to avoid testicular loss.

Abstract Background and Aim Proton pump inhibitors (PPIs) are a potential cause of gastric carcinogenesis after Helicobacter pylori eradication. Thus, appropriate management including chemoprevention is required. The aim of this study was to evaluate the association between nonsteroidal anti‐inflammatory drugs (NSAIDs) and the incidence of post‐eradication gastric cancer in PPI users. Methods A multicenter retrospective cohort study was conducted. Patients who used a PPI (≥30 days) after H. pylori eradication between 2014 and 2019 were analyzed in nine hospital databases. Gastric cancer incidence was a primary outcome, and their association with NSAIDs use and clinical factors was evaluated. Hazard ratios were adjusted by age, sex, smoking, and Charlson Comorbidity Index. Results During the mean follow‐up period of 2.38 years, 1.13% (31/2431) of all patients developed gastric cancer. The cumulative incidence of gastric cancer in PPI users was 0.25% at 1 year, 0.51% at 3 years, and 1.09% at 5 years in the NSAID users and 0.89% at 1 year, 2.32% at 3 years, and 3.61% at 5 years in nonusers. NSAIDs were associated with a lower gastric cancer risk (adjusted hazard ratio = 0.28, P = 0.005). No gastric cancer was observed in the cyclooxygenase‐2 inhibitor users (n = 256). NSAID use with high dose and long duration was significantly associated with a lower incidence of gastric cancer. Conclusion NSAIDs were associated with a 60% decrease in the gastric cancer incidence in H. pylori‐eradicated PPI users, with dose and duration response effects. NSAIDs may be effective for chemoprevention against PPI‐related gastric cancer.

Background and Aims: It remains unclear whether obesity increases the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C who achieved a sustained virological response (SVR) with antiviral therapy. Methods: In this multicenter cohort study, we enrolled patients with chronic hepatitis C who achieved SVR with interferon (IFN)-based therapy (IFN group) or direct-acting antiviral (DAA) therapy (DAA group) between January 1, 1990, and December 31, 2018. The patients underwent regular surveillance for HCC. Cumulative incidence of and the risk factors for HCC development after SVR were assessed using the Kaplan-Meier method and Cox proportional hazard regression analysis, respectively. Results: Among 2,055 patients (840 in the IFN group and 1,215 in the DAA group), 75 developed HCC (41 in the IFN group and 34 in the DAA group) during the mean observation period of 4.1 years. The incidence rates of HCC at 1, 2, and 3 years were 1.2, 1.9, and 3.0%, respectively. Multivariate analysis revealed that in addition to older age, lower albumin level, lower platelet count, higher alpha-fetoprotein level, and absence of dyslipidemia, obesity (body mass index ≥25 kg/m2) and heavy alcohol consumption (≥60 g/day) were independent risk factors for HCC development, with adjusted hazard ratio (HR) of 2.53 (95% confidence interval [CI]: 1.51–4.25) and 2.56 (95% CI: 1.14–5.75), respectively. The adjusted HR was not significant between the 2 groups (DAA vs. IFN; HR 1.19, 95% CI: 0.61–2.33). Conclusions: Obesity and heavy alcohol consumption increased the risk of HCC development after SVR.

Abstract Background and Aim Although gastric acid suppressants such as proton pump inhibitors (PPIs) and histamine‐2 receptor antagonists (H2RAs) are considered safe, the consequences of hypochlorhydria and hypergastrinemia caused by chronic use are unclear. This study aimed to investigate the association between the chronic use of gastric acid suppressants and high‐risk colorectal polyps, focusing on polyp size. Methods A population‐based, nested case–control study was conducted using data from the Japanese Diagnosis Procedure Combination database between 2014 and 2019. Cumulative PPI or H2RA use prior to polypectomy was evaluated during the study period. Endoscopic polypectomy was categorized as polypectomy 1 year prior to polypectomy. After adjusting for age, gender, and other confounders, a higher prevalence of high‐risk colorectal polyps was noted with PPI (OR: 2.67; 95% confidence interval: 2.37–3.01) and H2RA (OR: 1.86; 95% confidence interval: 1.52–2.26) use. Longer PPI or H2RA use was associated with increased risks of high‐risk colorectal polyps (P for trend

The high-pressure hydrogen tank for fuel cell vehicles is made by the prepreg winding method using carbon fiber reinforced plastics (CFRP). Unexpected destruction may occur in the high-pressure hydrogen tank due to internal pressure if an impact load is applied from the outside of it. Therefore, in this study, failure aspects occurred in the cross-ply and quasi-isotropic CFRP laminates by an impact penetration test and residual tensile strength were evaluated. In the impact penetration test, a steel ball was collided with the CFRP laminate using a gas gun. Then, fiber breakage and splitting failure occurred on the impact and back surfaces of the laminate were observed and interlaminar delamination was investigated by a cross-sectional observation. After the impact test, the CFRP laminate was cut into a strip-shaped specimen, and the residual tensile strength was measured. The residual tensile strength tends to decrease as the impact energy increases, and the strength of the penetrated specimens are about 27% (cross-ply) and 14% (quasi-isotropic) lower than that of the non-impact specimens. Finally, the damage propagation behavior of the penetrated specimens including fiber breakage, splitting failure and interlaminar delamination was analyzed by a finite element method. Damage initiation and propagation behavior of the specimens could be simulated, but the maximum loads obtained from the numerical results were lower than the experimental ones. From the results, the prediction method for residual tensile strength of penetrated CFRP laminates was discussed.

Spontaneous bile duct rupture is a rare condition in adults, with only 70 cases reported. Increased bile duct wall pressure may lead to rupture and biliary peritonitis. In this patient, the bile duct ruptured in the hepatic left triangular ligament. A 91-year-old man underwent endoscopic retrograde cholangiopancreatography for choledocholithiasis and endoscopic retrograde biliary drainage (ERBD) placement. One week later, removal of the ERBD and common bile duct stones and an endoscopic sphincterotomy (EST) were performed. Four days later, the patient had abdominal pain, increased inflammatory reaction, and jaundice. Abdominal computed tomography showed ascites, bile duct dilatation and fluid collection under the liver (10 cm in diameter). Emergency surgery was performed to drain the fluid. On laparotomy, encapsulated biliary ascites was seen. To search for the site of the leak, after cholecystectomy, a tube (C-tube) was inserted into the common bile duct via cystic duct stump. Because of uncontrollable bleeding, after packing with surgical gauze, the operation was temporarily stopped. The next day, reoperation was performed. Intraoperative cholangiography with contrast dye revealed the perforation site in the left triangular ligament and a partial resection was performed. Bile excretion from the C-tube was subsequently observed, but the patient’s jaundice did not improve. Although endoscopic retrograde cholangiopancreatography revealed that the EST site was normal, ERBD was placed again, and the jaundice gradually improved. Although EST was performed in this case, biliary peritonitis resulting from spontaneous bile duct rupture occurred. This case was very informative because biliary perforation may occur even after EST.

In this study, the damage-development behavior of carbon fiber-reinforced plastic (CFRP) laminates considering the nonlinear mechanical properties of a matrix resin was investigated through a numerical simulation based on a homogenization theory and continuum damage mechanics. A scalar damage variable was applied to elasto-viscoplastic constitutive equations, following which, the constitutive equations were introduced into the homogenization theory for elasto-viscoplastic materials. Uniaxial tensile tests including unloading and reloading phases under several strain rates were performed using a specimen made of an epoxy resin. The damage-development behavior of the unidirectional CFRP laminates was then analyzed using the homogenization theory. From the numerical results, viscoplastic behavior was observed in the stress–strain curves, and the stress decreased drastically as the damage of the epoxy resin developed. The microscopic distributions showed that the failure initiated at the epoxy resin around the fibers arranged along the loading direction and progressed by connecting the high damage variable regions of the epoxy resin. Uniaxial tensile tests of the unidirectional CFRP laminates were also performed to validate the numerical results. The experimental fracture stresses were distributed between the maximum and minimum stresses at the failure starting points obtained from the numerical results. Thus, it was confirmed that the proposed numerical method could analyze the damage-development behavior of CFRP laminates.

Metachronous gastric cancer often occurs after endoscopic resection. Appropriate management, including chemoprevention, is required after the procedure. This study was performed to evaluate the association between medication use and the incidence of metachronous gastric cancer after endoscopic resection. This multicenter retrospective cohort study was conducted with data from nine hospital databases on patients who underwent endoscopic resection for gastric cancer between 2014 and 2019. The primary outcome was the incidence of metachronous gastric cancer. We evaluated the associations of metachronous gastric cancer occurrence with medication use and clinical factors. Hazard ratios were adjusted by age and Charlson comorbidity index scores, with and without consideration of sex, smoking status, and receipt of Helicobacter pylori eradication therapy during the study period. During a mean follow-up period of 2.55 years, 10.39% (140/1347) of all patients developed metachronous gastric cancer. The use of antibiotics other than those used for H. pylori eradication was associated with a lower incidence of metachronous gastric cancer than was non-use (adjusted hazard ratio (aHR) 0.56, 95% confidence interval (CI) 0.38–0.85, p = 0.006). Probiotic drug use was also associated with a lower incidence of metachronous gastric cancer compared with non-use (aHR 0.29, 95% CI 0.091–0.91, p = 0.034). In conclusion, the use of antibiotics and probiotic drugs was associated with a decreased risk of metachronous gastric cancer. These findings suggest that the gut microbiome is associated with metachronous gastric cancer development.

Hepatitis E virus (HEV) is a growing public health problem in many countries. In this study, we investigated HEV seroprevalence among the general population in the Siem Reap province, Cambodia, and performed HEV genetic analysis with the aim to develop an HEV prevention strategy. This seroepidemiological cross-sectional study conducted from 2010 to 2014 included 868 participants from four different locations in Siem Reap province, Cambodia. They answered questionnaires and provided blood samples for the analysis of hepatitis virus infections. Among the participants (360 men and 508 women; age range, 7-90 years), the prevalence of anti-HEV IgG was 18.4% (95% confidence interval: 15.9-21.0); HEV RNA was detected in two participants (0.23%) and was classified as genotype 3 and 4. Full-length genome of the genotype 4 isolate, CVS-Sie10, was sequenced; it contained 7,222 nucleotides and three ORFs and demonstrated high sequence identity with the swine China isolates swGX40 (95.57%), SS19 (94.37%), and swDQ (91.94%). Multivariate logistic regression analysis revealed that men, elderly people, and house workers were risk groups significantly associated with the positivity for anti-HEV IgG. This is the first report on the detection of HEV genotype 4 in humans in Cambodia and on the complete genome sequence of HEV genotype 4 from this country. Our study demonstrates that new HEV infection cases occur frequently among the general population in Cambodia, and effective preventive measures are required.