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Strain-engineering can be used to increase the activity and selectivity of an electrocatalyst. Tensile strain is known to improve the electrocatalytic activity of palladium electrodes for reduction of carbon dioxide or dioxygen, but determining how strain affects the hydrogen evolution reaction (HER) is complicated by the fact that palladium can absorb hydrogen concurrently with HER. We report here a custom electrochemical cell that applies tensile strain to a flexible working electrode that enabled us to resolve how tensile strain affects hydrogen absorption and HER activity for a thin film palladium electrocatalyst. When the electrodes were subjected to mechanically-applied tensile strain, the amount of hydrogen that absorbed into the palladium decreased, and HER electrocatalytic activity increased. This study showcases how strain can be used to modulate the hydrogen absorption capacity and HER activity of palladium. © 2020 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.The charge density of DNA is a key parameter in strand hybridization and for the interactions occurring between DNA and molecules in biological systems. Due to the intricate structure of DNA, visualization of the surface charge density of DNA nanostructures under physiological conditions was not previously possible. Here, we perform a simultaneous analysis of the topography and surface charge density of DNA nanostructures using atomic force microscopy and scanning ion conductance microscopy. The effect of in situ ion exchange using various alkali metal ions is tested with respect to the adsorption of DNA origami onto mica, and a quantitative study of surface charge density reveals ion exchange phenomena in mica as a key parameter in DNA adsorption. This is important for structure-function studies of DNA nanostructures. The research provides an efficient approach to study surface charge density of DNA origami nanostructures and other biological molecules at a single molecule level. © 2020 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.Asthma is a common chronic disease in pregnancy that affects placental function, fetal growth and associated with cardio-metabolic disorders in the offspring but the mechanisms are unknown. This study explored whether maternal asthma in pregnancy is associated with the development of offspring microvascular structure and if it was related to biomarkers of angiogenesis in utero. Children aged 4 to 6 years, born to either asthmatic mothers (n=38) or healthy controls (n=25) had their retinal microvascular structure examined. Maternal plasma placental growth factor (PlGF) concentrations at 18 and 36 weeks gestation were measured. There was a significant global difference in all retinal microvascular measures between children of asthmatic mothers relative to controls and increased retinal venular tortuosity in children born to asthmatic mothers (7.1 (95% CI 0.7- 13.5); p=0.031). A rise in plasma PlGF from 18 to 36 weeks' gestation was observed in the control population which was significantly lower in the asthma group by 190.9 pg/mL. PlGF concentrations were correlated with microvascular structure including arteriolar branching and venular tortuosity. These exploratory findings indicate that exposure to maternal asthma during pregnancy is associated with persistent changes in microvascular structure in childhood that may be driven by alterations to angiogenic mechanisms in utero. This article is protected by copyright. All rights reserved.Angelico et al. described the impact of the novel coronavirus (COVID-19) outbreak on organ transplantation in Italy (1), where only one center in Milan has limited transplant activity to most urgent cases. The rest of the country continued with the regular allocation policy (1). In Switzerland, which has more COVID-19 cases per capita than Italy (2), we have opted for a stepwise approach. This article is protected by copyright. All rights reserved.In January 2020, Novel Coronavirus Disease 2019 (COVID-19) resulted in a global pandemic, creating uncertainty towards the management of Liver Transplantation (LT) programmes. Lombardy has been the most affected region in Italy The current mortality rate of COVID-19 patients is 18,3% (10022 deaths) (April 10th) with hospitals in Lombardy having to expand the total number of ICU beds from 724 to 1381 to accommodate infected patients. There has been a drastic decrease in liver donors. From February 23rd until April 10th, 17 LTs were performed in Lombardy. Mean donor age was 49 years (range 18-74) whereas mean recipient age was 55 (13-69); mean MELD Score was 12 (6-24). All donors underwent screening for SARS CoV-2 prior to LT. Two patients tested positive after LT, and one patient died for COVID on POD 30. 16 patients are alive after an average of 30 days post LT (range 3-46). 10 patients have been discharged. This study has found no specific reason concerning the safety of recipients, to stop liver transplantation programmes. [https://www.selleckchem.com/products/skf-34288-hydrochloride.html selleck kinase inhibitor] Several Key-lessons from our experience are reported. However, due to the complex circumstances which surround the viral outbreak, the cessation or a reduction in LT activity is a pragmatic requirement. This article is protected by copyright. All rights reserved.OBJECTIVE To investigate the explicitness and variability of the definition of periodontal health in current scientific literature. MATERIAL AND METHODS The authors conducted a systematic literature review using PubMed and CENTRAL (2013-01/2019-05) accoridng to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the guidelines of the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) statement. RESULTS A total of 51 papers met the predefined inclusion criteria. Of these, 13 papers did not report any explicit definitions of periodontal health. Out of the 38 remaining articles, half of them used a reference to support their definition and half of them not. The studies published in periodontics-related journals or those that scored a low risk of bias for the methodical quality presented more explicit and valid definitions. Probing pocket depth was the most frequently used individual parameter for defining periodontal health. However, there were substantial variations in the methods of measurement and cut-off values.