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The radial variation of rays within the stems of Dahurian larch and Japanese larch growing in Korea was studied to obtain valuable information to identify the two species and determine wood quality. Uniseriate ray height, fusiform ray height, ray number, ray spacing, and epithelial cell number were investigated by optical microscopy. The heights of uniseriate and fusiform rays and epithelial cell numbers in Dahurian larch were lower than those in Japanese larch. Dahurian larch wood had greater ray number and ray spacing than Japanese larch wood. In both species, the heights of uniseriate and fusiform rays and epithelial cell number increased with increasing growth ring number but then stabilized from a certain growth ring number. However, ray number and ray spacing decreased with age but were stable toward the bark. There were significant differences in all ray properties between the two species. Furthermore, in both species, the number and spacing of rays showed a significant negative correlation with uniseriate ray height. The relationships between uniseriate and fusiform ray height, and between ray spacing and ray number were significantly positive. In conclusion, the results from this study provide basic information that can be used to identify these species, and the quality indices from ray properties will improve the effective utilization of the two woody species. [ABSTRACT FROM AUTHOR]

Background: Hypervascular hyperplastic nodules (HHNs) occasionally develop in patients with alcoholic liver cirrhosis (ALC) and show arterial enhancement, thus mimicking hepatocellular carcinoma (HCC). Importantly, HHN as a benign lesion should be distinguished from HCC.Purpose: To evaluate the value of gadoxetic acid-enhanced MRI (Gd-EOB-MRI) and diffusion-weighted imaging (DWI) in distinguishing HHN from small (<3 cm) hypervascular HCC (hHCC) in patients with ALC.Study Type: Retrospective case-control study.Field Strength/sequence: 3.0T/in- and out-of-phase, T1 -weighted, T2 -weighted, diffusion-weighted, apparent diffusion coefficient, and dynamic gadoxetic acid-enhanced images.Population: Among 560 patients with ALC who underwent Gd-EOB-MRI and DWI, 12 patients with 28 HHNs and 22 patients with 29 hHCCs smaller than 3 cm were included.Assessment: The following MRI features were evaluated by three independent radiologists: signal intensity (SI) on T1 -weighted, T2 -weighted, diffusion-weighted, and hepatobiliary phase (HBP) images; shape, homogeneity, and margin on HBP; diffusion restriction; intralesional fat; necrosis; hemorrhage; washout on portal venous phase (PVP) and/or transitional phase (TP); and capsular enhancement. Quantitative analysis was also conducted.Statistical Tests: Univariate and multivariate analyses were performed to determine the significant MRI findings, and their diagnostic performance for the prediction of HHN was analyzed.Results: Lesion size of ≤16 mm (odds ratio [OR], 24.41; P = 0.007), low-to-iso SI on DWI (OR, 26.92; P = 0.007), and absence of washout on PVP and/or TP (OR, 31.84; P = 0.009) were significant independent factors for predicting HHN. When all three criteria were satisfied, the specificity was 100%. Compared with hHCCs, HHNs showed significantly smaller size (mean, 13.8 mm vs. 19.9 mm; P < 0.001) and higher mean SI value (994.0 vs. 669.5) and lesion-to-liver SI ratio (1.045 vs. 0.806) on HBP (P < 0.001, respectively).Data Conclusion: Gd-EOB-MRI and DWI may be helpful in differentiating HHN from small hHCC in patients with ALC.Level Of Evidence: 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:70-80. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the alternating current electrical properties of the heterostructured polymer light-emitting diode. Experimental details; Results and discussion; Conclusions.

Presents information on a study which analyzed the frequency dependent dielectric constant of amorphous ferroelectrics using the Langevin equation. Experimental details; Results and discussion; Conclusions.

Objectives: To assess a correlation between the preoperative diffusion-weighted imaging (DWI) and early recurrence (<2 years) and to determine the best DWI parameters as the risk factor of early recurrence after surgery in single hepatocellular carcinoma (HCC).Methods: The study included 114 patients with surgically resected single HCC (≤5 cm) who underwent preoperative magnetic resonance imaging (MRI) with DWI. Radiologists evaluated the diffusion restriction of the tumours using qualitative assessment and the mean and minimum apparent diffusion coefficient values (ADCmean and ADCmin) of the tumours using quantitative measurement. Clinical and laboratory findings and DWI parameters as a risk factor for early recurrence were identified by using Cox proportional hazards model.Results: No significant difference was observed in early recurrence rates of HCCs between those with and those without diffusion restriction (p = 0.484). Early recurrence rates of HCCs with ADCmean and ADCmin values lower than the optimal cut-offs (1.023 and 0.773 × 10-3 mm2/s, respectively) were significantly higher compared with those with values higher than the optimal cut-offs (p = 0.001 and p < 0.001, respectively). In the multivariable analysis, tumour size [hazard ratio (HR) per centimetre, 2.011; 95% CI, 1.304-3.102; p = 0.002] and ADCmin ≤0.773 × 10-3 mm2/s (HR, 13.339; 95% CI, 4.422-40.240; p < 0.001) were independent risk factors for early HCC recurrence.Conclusions: DWI is a promising imaging tool for early recurrence of HCC. Among qualitative and quantitative assessments of DWI, ADCmin is a significant risk factor for early recurrence after surgery in single HCC.Key Points: • The performance of minimum apparent diffusion coefficient (ADCmin) is significantly better than that of mean apparent diffusion coefficient (ADCmean) for identifying early recurrence. • ADCmin is a significantly independent risk factor of early HCC recurrence after surgery. • ADCmin correlates with early recurrence after curative resection of single HCC, reflecting histopathological features of the tumours including histological grade and microvascular invasion. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the correlation between tumour differentiation or stage of gallbladder cancer (GBC) and the apparent diffusion coefficient (ADC), as well as to assess whether ADC value can predict long-term disease-free survival (DFS) after surgery.Methods: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between March 2008 and June 2016, 79 patients who underwent magnetic resonance (MR) imaging with diffusion-weighted image and subsequent surgery for GBC were included in this study. Correlations between quantitative ADC values and tumour differentiation or stage based on the American Joint Committee on Cancer (AJCC) were assessed using Spearman's correlation analysis. Prognostic factors for DFS were identified with multivariate Cox regression analysis using imaging and clinical characteristics.Results: All patients were classified as having well- (n = 18), moderately (n = 35) or poorly differentiated GBCs (n = 26). The ADC value of GBCs was significantly correlated with tumour differentiation and AJCC stage (p < 0.001 and p < 0.001, respectively). Sixty-nine patients were followed up for 2.0-92.4 months (median, 23.5 months). On multivariate analysis, the significant prognostic factor for DFS was not tumour differentiation or AJCC stage but a binary tumour ADC value (hazard ratio, 4.29; p = 0.009). DFS rates were significantly different according to the classification of tumour ADC value (cut-off value = 1.04 × 10-3 mm2/s; p = 0.004).Conclusion: The ADC value of GBCs was significantly correlated with tumour differentiation as well as AJCC stage. In addition, it predicted long-term outcomes after surgery in patients with GBC.Key Points: • ADC values of GBC and tumour differentiation were negatively correlated. • Lower ADC values of GBC were significantly correlated with higher tumour stage. • Tumour ADC value could be useful for risk stratification of GBC patients. [ABSTRACT FROM AUTHOR]