AIMS The levator-urethra gap (LUG), the distance between the urethral lumen center and levator insertion on the inferior pubic rami, can be used for diagnosing levator avulsion, with a previously suggested cutoff of LUG ≥2.5 cm. The aim of this study is to determine an optimal cutoff value for LUG measurements in a high-risk patient population. METHODS Women followed prospectively after sustaining obstetric anal sphincter injury underwent an interview pelvic examination questionnaires and four-dimensional-transperineal ultrasound examination. Levator avulsion was diagnosed on contraction using tomographic ultrasound imaging. Ultrasound datasets were analyzed offline at a later time blinded to previous data. LUG was measured on each side of the three central slices, yielding six measurements and the highest available value was obtained on each side. Different cutoffs were evaluated using receiver-operating characteristics (ROC) curve analysis and Youden's test. The cutoff was validated against symptoms and signs, and sonographic findings using logistic regression analysis. RESULTS A total of 618 complete datasets were available for analysis, median age 29 years, median body mass index of 23.4 kg/m2 , parity 1, and 26.4% instrumental deliveries. Youden's test and ROC curve analysis gave the best area under the curve of 0.869 for a cutoff of 2.305 (95% confidence interval, 0.839-0.9). Women diagnosed with avulsion based on this cutoff were more symptomatic, whereas using larger cutoffs missed more avulsion defects. CONCLUSION LUG measurement is useful but should be individualized to the population studied, in our case, in a high-risk population, 2.305 cm was the optimal cutoff. Using larger cutoffs may be more specific but is likely to miss more cases. © 2020 Wiley Periodicals, Inc.A simple, fast and sensitive analytical protocol using fabric phase sorptive extraction followed by HPLC-UV has been developed and validated for the extraction of five parabens including methylparaben, ethylparaben, propylparaben, butylparaben and benzylparaben. In the present work, sol-gel polyethylene glycol coated fabric phase sorptive extraction membrane is used for the preconcentration of parabens (polar) from complex matrices. The use of fabric phase sorptive extraction membrane provides a high surface area which offers high sorbent loading, shortened equilibrium time and overall decrease in the sample preparation time. Various factors affecting the performance of fabric phase sorptive extraction including extraction time, eluting solvent, elution time and pH of the sample matrix were optimized. Separation was performed using a mobile phase consisting of water acetonitrile (6337; v/v) at an isocratic elution mode at a flow rate of 0.9 mL/min with wavelength at 254 nm. The calibration curves of the target analytes were prepared with good correlation coefficient values (r2 > 0.9955). The LOD values range from 0.252 to 0.580 ng/mL. Finally, the method was successfully applied to various cosmetics and personal care product samples such as rose water, deodorant, hair serum and cream with extraction recoveries ranged between 88 to 122% with RSD less then 5%. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.Dendrite growth poses a significant problem in the design of modern batteries, as it can lead to capacity loss and short-circuiting. Recently it has been proposed that self-diffusion barriers might be used as a descriptor for the occurrence of  dendrite growth in batteries. As surface strain effects can modify dendritic growth, we present first-principles density functional theory calculations of the dependence of metal self-diffusion barriers on applied surface strain for a number of metals that are used as charge carriers in batteries. Overall we find a rather small strain dependence of the barriers. We mainly attribute this to cancellation effects in the strain dependence of the initial and the transition states in diffusion. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.To investigate divalent metal ion (Me2+ ) requirements in electrophilic biocatalysis, we compared Mg2+ , Mn2+ , Co2+ , Zn2+ , Cu2+ , Ni2+ , Cd2+ , Ca2+ , and Fe2+ activities with 13 enzymes executing nucleotidyl and/or phosphoryl transfer. We find that each Me2+ ion was highly catalytically active with one or more of the related enzymes. This result suggests that features of Me2+ coordination at the active center, and/or the enzyme-mediated presentation of the reactants to the chelated Me2+ , rather than the nature of the Me2+ , determine the ability of the Me2+ to support catalysis. At physiological pH, all the tested Me2+ , with the exception of Mg2+ , produced insoluble complexes with inorganic phosphate (Pi ) and bicarbonate (HCO3 - ). These data suggest that early in the development of life, bioavailability as well as biocompatibility with these abundant cellular metabolites may have been decisive factors in the choice of Mg2+ as major ion for biocatalysis. Taking into account the concentrations of inorganic ions in the ancient environment in which the first cells emerged, as inferred from "chemistry conservation principle", the choice of Mg2+ was predetermined prior to the origin of life. This article is protected by copyright. see more All rights reserved.Although the effective transmission of the H5N1 virus from humans to humans has yet to be further observed, humans are at increased risk of a pandemic caused by H5N1. In order to fully evaluate the seroprevalence and risk factor of highly pathogenic avian influenza A (H5N1) virus infection among in mainland China, we performed a systematic review and meta-analysis. In this review, we searched literature on the seroprevalence of H5N1 infection among humans in mainland China from 1 January 1997 to 20 October 2018 in English and Chinese databases, including PubMed, Google scholar, Cochrane library, Clinical Trial, VIP, CNKI and WanFang database. We made a selection according to the title and the abstract of paper, and then, we excluded duplicated literature, and data incomplete literature according to the exclusion criteria we formulated. Finally, we extracted how many humans have H5N1 infection from the obtained studies to establish the seroprevalence of H5N1 infection among humans in mainland China. A total of 56 studies (including data of 35,159 humans) were compliant with our criteria.