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Ordovician diorite-quartz diorite mylonite (Saganoseki quartz diorite) was discovered in Sambagawa metamorphic terrane at the northern margin of Saganoseki Peninsula, Kyushu Island, Japan. The LA-ICP-MS zircon U–Pb geochronology revealed that the intrusion age of Saganoseki quartz diorite was 473.3 ​± ​3.6 ​Ma. These rocks show the volcanic arc affinity based on the trace element composition. On the basis of geochronological and geochemical results, Saganoseki quartz diorite is considered to be a member of the Early Paleozoic igneous rocks of the Kurosegawa tectonic zone. Saganoseki quartz diorite is located just south of the Median Tectonic Line (MTL) and is in close contact with the pelitic and psammitic schist without any brittle shear zone. U–Pb ages of detrital zircon grains from two psammitic schists show the estimated sedimentation age of early Late Cretaceous, indicate that these psammitic schists are the member of Sambagawa metamorphic rocks. Together with these results and the mode of occurrence in the field, we argue that the Early Paleozoic igneous rocks of the Kurosegawa tectonic zone existed as an upper structural unit of the Sambagawa terrane. This relationship is the key to reconstruct the Mesozoic tectonics of Japan as a part of East Asia, and its evolution through time. Image 1 • Zircon U–Pb age reveals new discovery of Early Paleozoic rocks at the Kyushu, Japan. • Direct contact of ca. 473 Ma Kurosegawa tectonic zone and Sambagawa schist was found. • Early Paleozoic rocks were widely distributed than the current area of distribution. • New tectonic framework is proposed around Median Tectonic Line from Late Cretaceous. [ABSTRACT FROM AUTHOR]

Although slab-derived fluid significantly affects melt generation and dynamics within subduction zones, its amount and distribution are not sufficiently constrained at present. Herein, we use isotopic systematics of arc volcanic rocks, subducting materials, and intrinsic mantle components prior to metasomatism, to quantify the contribution of the slab-derived fluid that metasomatizes the overlying mantle wedge beneath the entire area of Japan arcs. Simultaneous application of several multivariate statistical analyses (clustering analysis and principal/independent component analyses) to the isotopic data set allows Japan arcs to be broadly divided into eastern and western parts at the first order. Moreover, a clear higher-order inter-arc segmentation is observed, together with some intra-arc variations that possibly correspond to the heterogeneity of incoming plates. Inter-arc segmentation is shown to be primarily controlled by the geometrical parameters of the slab and the arc (e.g., subduction of a single plate or double plates beneath either oceanic or continental crust), which results in differences between mantle wedge and slab thermal conditions. Accordingly, the Kuril and Izu arcs, which have thin arc crusts (~20 km), exhibit the lowest extent of slab-derived fluid addition (0.1 wt%) to the mantle wedge, while the NE Japan arc, with a thicker arc crust (up to 36 km), features a higher value of 0.2 wt%, although the slab thermal parameters for these three arcs are essentially the same. The Central Japan arc shows the highest extent of slab-derived fluid addition (>1.0 wt%) because of the overlapping subduction of Pacific and Philippine Sea slabs, while the SW Japan and Ryukyu arcs feature moderate values of ~0.5 wt%. Moreover, a clear exotic plume zone and spots are observed in SW Japan and the Japan Sea. In addition to the variability of slab-derived fluid composition, the intrinsic mantle composition (before slab-derived fluid–induced metasomatism) shows a clear along-arc variation that is possibly caused by a large-scale mantle flow from the continental side. Thus, slab-derived fluid addition and mantle composition variability equally contribute to inter-arc segmentation, which highlights the importance of both local and regional thermal flow structures of slab-mantle systems. Unlabelled Image • To quantify the contribution of the slab-derived fluid beneath the entire area of Japan arcs. • Multivariate statistical analyses to isotopic data allows Japan arcs to be broadly divided into eastern and western parts. • Inter-arc segmentation is primarily controlled by the slab-arc geometrical parameters, causing different thermal condition. [ABSTRACT FROM AUTHOR]

Background: Therapeutic strategies for flat elevated (0-IIa) lesions in the stomach diagnosed as adenoma by biopsy are currently not established, because some difficulties have previously been reported in the evaluation of vascular patterns alone for the differential diagnosis between adenoma and carcinoma. Objective: We attempted to evaluate the 0-IIa lesions diagnosed as adenoma by using magnifying endoscopy with narrow-band imaging (MENBI) to distinguish them as either adenoma or carcinoma. Setting: Department of Gastroenterology, Fujita Health University. Patients: Fourteen adenomatous lesions (6 adenomas and 8 carcinomas confirmed postoperatively) diagnosed with preoperative biopsies from patients who had undergone endoscopic submucosal dissection were evaluated. Interventions: We selected 5 sites per lesion for MENBI. Selected sites were divided into superficial structures (SSs) and irregular microvascular patterns (IMVPs). Main Outcome Measurements: The rate of SSs and IMVPs in adenoma and carcinoma. Results: Significant SSs were tubular in the adenoma and unclear in the carcinoma. Regarding IMVP subcategories, (1) slight intrastructual irregular microvascular patterns (ISIMVPs) accounted for 97%, (2) severe ISIMVPs accounted for 0%, (3) fine networks accounted for 3%, and (4) corkscrews accounted for 0% of cases in the adenomas. The corresponding proportions in the carcinomas were (1) 40%, (2) 15%, (3) 45%, and (4) 0%. Severe ISIMVPs and fine networks were significant findings for carcinomas. Limitations: The number of cases was limited. Conclusions: Our combined evaluation method using MENBI offers the ability to establish proper therapeutic strategies for lesions that are difficult to identify as adenoma or carcinoma. [Copyright &y& Elsevier]

Background: Magnifying narrow-band imaging (NBI) endoscopy clearly visualizes superficial gastric mucosal patterns and capillary patterns. Objective: To investigate gastric mucosal patterns by using magnifying NBI endoscopy and identify any relationship between those patterns and Helicobacter pylori–induced gastritis. Design: Gastric mucosal patterns seen with magnifying NBI in uninvolved gastric corpus were divided into the following categories: normal—small, round pits with regular subepithelial capillary networks; type 1—slightly enlarged, round pits with unclear or irregular subepithelial capillary networks; type 2—obviously enlarged, oval or prolonged pits with increased density of irregular vessels; and type 3—well-demarcated oval or tubulovillous pits with clearly visible coiled or wavy vessels. Setting: Department of Gastroenterology, Fujita Health University. Patients: This study involved 106 participants undergoing upper endoscopy. Results: H pylori infection–positive ratios of normal and types 1, 2, and 3 patterns were 7.5%, 92.9%, 94.5%, and 66.7%, respectively. Sensitivity and specificity for types 1 + 2 + 3 for detection of H pylori positivity and type 3 for detection of intestinal metaplasia were 95.2%, 82.2%, 73.3%, and 95.6%, respectively. Development of mucosal patterns from normal to types 1, 2, and 3 was correlated with all histological parameters (P < .0001), lower pepsinogen I/II ratios (P < .0001), and degree of endoscopic atrophy (P < .0001). Sensitivity and specificity of type 3 for the prediction of severe histological atrophy was also better than those of serum pepsinogen level and standard endoscopy. Limitations: Only 1 endoscopist performed endoscopic procedures, and interobserver agreement could not be assessed. Conclusions: Magnifying NBI endoscopy is useful for predicting H pylori infection and the histological severity of gastritis and is valuable for predicting gastric atrophy in the entire stomach. [Copyright &y& Elsevier]

Abstract: The objective of this study was to evaluate the performance of handheld XRF analyzers on wood that has been treated with a preservative containing arsenic. Experiments were designed to evaluate precision, detection limit, effective depth of analysis, and accuracy of the XRF arsenic readings. Results showed that the precision of the XRF improved with increased sample concentration and longer analysis times. Reported detection limits decreased with longer analysis times to values of less than 1mg/kg or 18mg/kg, depending on the model used. The effective depth of analysis was within the top 1.2cm and 2.0cm of sample for wood containing natural gradients of chemical preservative and concentration extremes, respectively. XRF results were found to be 1.5–2.3 times higher than measurements from traditional laboratory analysis. Equations can be developed to convert XRF values to results which are consistent with traditional laboratory testing. [Copyright &y& Elsevier]

Background & Aims We aimed to establish a comorbidity index for small bowel vascular diseases (SBVD) associated with small bowel bleeding (SBB) and recurrent bleeding. Methods We performed a retrospective analysis of 404 patients diagnosed with SBB via double-balloon enteroscopy, at 2 hospitals in Japan from June 2003 through July 2016. We collected data on comorbidities, computed Charlson Comorbidity Index and anticoagulation and risk factors in atrial fibrillation (ATRIA) scores, and analyzed associations with SBVD, rebleeding, and overall survival associated with bleeding and/or comorbidities. We used these data to develop a comorbidity index to identify patients at risk for SBVD, rebleeding, and reduced survival time. We validated our findings in a separate, prospective cohort of 88 patients with SBB. Results We developed a weighted index (the Ohmiya index) that identified patients who developed SBVD with an area under the receiver operating characteristic (AUROC) curve of 0.7758; this value was higher than that of the Charlson index score (0.6828; P <.0001) or ATRIA score (0.6728; P <.0001) alone. Among the 51 patients taking oral anticoagulants, there was no significant difference in AUROCs for the Ohmiya score (0.5254) vs the outcomes registry for better informed treatment score (0.5857; P =.4300). In the retrospective cohort, the Ohmiya index identified patients with SBVD with 68% sensitivity (93/137), 84% specificity (223/267), and 78% accuracy (316/404); in the validation cohort, these values were 63% (22/35), 85% (45/53), and 76% (67/88), respectively. Onset age <50 years and index score <2 identified patients with Meckel's diverticulum and Crohn's disease with 53% accuracy. Onset age ≥50 years and index score <2 identified patients with inflammatory diseases, drug-induced injuries, or tumors with 72% accuracy. An index score ≥2 identified patients with SBVD with 68% accuracy, regardless of age. Among patients with Ohmiya index scores ≥2, 33% had rebleeding; among patients with scores <2, 15% had rebleeding (hazard ratio for score ≥2, 1.729; 95% CI, 1.038–2.882; P =.0355). Conclusion We developed an index, based on comorbidities and age of onset of SBB, that identified patients at risk for rebleeding and vascular disease (for example, enteroscopic hemostasis for SBVD, medication for inflammatory diseases, surgery with enteroscopic tattooing for tumors and diverticula). UMIN: 000025693. [ABSTRACT FROM AUTHOR]