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The indications for external beam radiotherapy (RT) in differentiated thyroid carcinomas (DTC) are still undefined. The objective of this study was to synthesize current evidence defining the role of postoperative RT in patients with DTC. A systematic review and meta-analysis were done. Included studies compared oncologic outcomes and toxicity of RT vs no RT in patients with DTC. Nine studies were included, two prospective and seven retrospective cohorts. RT improved 5-year locoregional recurrence-free survival but not overall survival and distant metastasis failure-free survival. The locoregional control benefit was seen in patients at increased risk for recurrence, including those with advanced age, locoregionally advanced disease, gross or microscopic residual tumor, and structural invasion. Serious RT-related acute and late toxicities were rare. Available evidence suggests that postoperative RT can improve locoregional control in high-risk DTC with acceptable toxicity. Further prospective studies are warranted. © 2020 Wiley Periodicals, Inc.PURPOSE To improve the slice profile quality obtained by RF half-pulse excitation for 2D-UTE applications. METHODS The overall first-order and zero-order phase errors along the slice-selection direction were obtained with the help of an optimization task to minimize the out-of-slice signal contamination from the calibration 1-dimenisonal (1D) profile data. The time-phase-error evolution was approximated from the k-space readout data, which were acquired primarily for correction of the readout trajectories during data regridding to the rectilinear grids. The correction of the slice profile was achieved by rephasing gradient pulses applied immediately after the end of excitation. The total prescan calibration typically took less than 2 minutes. RESULTS The improved image quality using the proposed calibration method was demonstrated both on phantoms and on ankle images obtained from healthy volunteers. It was demonstrated that calibration can be performed either as a separate water phantom measurement or directly as a prescan procedure. CONCLUSION The slice-profile distortion from the half-pulse excitation could substantially affect the overall fidelity of 2D-UTE images. The presented experiments proved that the image quality could be substantially increased by application of the proposed slice-correction method. [https://www.selleckchem.com/products/l-arginine-l-glutamate.html L-Arginine ic50] © 2020 International Society for Magnetic Resonance in Medicine.The reaction mechanisms, phase development and kinetics of the hydrothermal synthesis of hexagonal-YMnO3 from Y2O3 and Mn2O3 using in situ X-ray diffraction are reported under different reaction conditions with temperatures ranging from 300 to 350 °C, and using 1, 5 and 10 M KOH, and 5 M NaOH mineraliser. Reactions initiated with Y2O3 hydrating to Y(OH)3, which then dehydrated to YO(OH). Higher temperature and KOH concentration led to faster, more complete dehydrations. However, 1 M KOH led to YO(OH) forming concurrently with Y(OH)3 before Y(OH)3 fully dehydrated, but yielded a very low phase purity of hexagonal-YMnO3. Using NaOH mineraliser, no YO(OH) was observed. Dehydration also initiated at a higher temperature in the absence of Mn2O3. The evolution of Rietveld refined scale factors was used to determine kinetic information and approximate activation energies for the reaction. The described hydrothermal synthesis offers a fast, low temperature method for producing anisometric h-YMnO3 particles. © 2020 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.Shimalactones A and B are neuritogenic polyketides possessing characteristic oxabicyclo[2.2.1]heptane and bicyclo[4.2.0]octadiene ring systems that are produced by the marine fungus Emericella variecolor GF10. We identified a candidate biosynthetic gene cluster and conducted heterologous expression analysis. Expression of ShmA polyketide synthase in Aspergillus oryzae resulted in the production of preshimalactone. Aspergillus oryzae and Saccharomyces cerevisiae transformants expressing ShmA and ShmB produced shimalactones A and B, thus suggesting that the double bicyclo-ring formation reactions proceed non-enzymatically from preshimalactone epoxide. DFT calculations strongly support the idea that oxabicyclo-ring formation and 8π-6π electrocyclization proceed spontaneously after opening of the preshimalactone epoxide ring through protonation. We confirmed the formation of preshimalactone epoxide in vitro, followed by its non-enzymatic conversion to shimalactones in the dark. © 2020 Wiley-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.BACKGROUND AND AIMS The Liver Imaging Reporting and Data System (LI-RADS) category M (LR-M) was introduced to preserve the high specificity of LI-RADS algorithm for diagnosing hepatocellular carcinoma (HCC). We aimed to systematically determine the probability of the LR-M for HCC and non-HCC malignancy, and to determine the sources of heterogeneity between reported results. METHODS Original studies reporting the probability of LR-M for HCC and non-HCC malignancy on magnetic resonance imaging (MRI) were identified in MEDLINE and EMBASE. The meta-analytic pooled percentages of HCC and non-HCC in LR-M were calculated. Meta-regression analysis was performed to explore study heterogeneity. The meta-analytic frequency of each LR-M imaging feature was determined. RESULTS We found 10 studies reporting the diagnostic performance of LR-M (1819 lesions in 1631 patients), and six reporting the frequency of LR-M imaging features. The pooled percentages of HCC and non-HCC malignancy for LR-M were 28.2% (95% confidence interval [CI], 23.8%-33.1%; I2 &nbsp;=&nbsp;83%) and 69.6% (95% CI, 64.6%-74.1%; I2 &nbsp;=&nbsp;83%) respectively. The study type and MRI scanner field strength were significantly associated with study heterogeneity (P&nbsp;≤&nbsp;.04). Of the seven imaging features, rim arterial phase hyperenhancement showed the highest frequency in both non-HCC (48.9%; 95% CI, 43.0%-54.8%) and HCC groups (9.8%; 95% CI, 6.9%-13.6%). CONCLUSIONS The LR-M category most commonly included non-HCC malignancy but also included 28.2% of HCC. Substantial study heterogeneity was noted, and it was significantly associated with study type and MRI scanner field strength. In addition, the frequency of LR-M imaging features was variable. © 2020 John Wiley &amp; Sons A/S. Published by John Wiley &amp; Sons Ltd.