Zobrazení zdroje stránky Hjortgottlieb5994

We show that the mixing of organic solvents with pure water leads to the spontaneous formation of suspended nano-entities which exhibit long-term stability on the scale of months. A wide range of solvents representing different functional groups are studied methanol, ethanol, propanol, acetone, DMSO and formamide. We use various physical and chemical analytical techniques to provide compounded evidence that the nano-entities observed in all these aqueous solvent solutions must be gas-filled nanobubbles as they cannot be attributed to solvent nanodroplets, impurities or contamination. The nanobubble suspensions are characterized in terms of their bubble size distribution, bubble number density and zeta potential. The bubble number density achieved is a function of the type of solvent. It increases sharply with solvent content, reaching a maximum at an intermediate solvent concentration, before falling off to zero. We show that, whilst bulk nanobubbles can exist in pure water, they cannot exist in pure organic solvents and they disappear at some organic solvent-water ratio depending on the type of solvent. The gas solubility of the solvent relative to water as well as the molecular structure of the solvent are determining factors in the formation and stability of bulk nanobubbles. These phenomena are discussed and interpreted in the light of the experimental results obtained.Lead is a heavy metal which has long been known to have toxic effects on the body. However, much remains to be learnt about the labile lead pool and cellular uptake of lead. [https://www.selleckchem.com/products/fti-277-hcl.html FTI277] We report here RPb1 that undergoes a 100-fold increase in fluorescence emission in the presence of Pb2+, and which can be applied to study the labile lead pool within cells. We demonstrate the capacity of RPb1 for investigating labile lead pool in DLD-1 cells and changes in labile lead during differentiation of K562 cells.Correction for 'Deformability-induced lift force in spiral microchannels for cell separation' by Ewa Guzniczak et al., Lab Chip, 2020, 20, 614-625.BACKGROUND Previous studies have shown that fasting produces a potential effect in the prevention and treatment of many diseases. However, the role of fasting in people with overweight or obesity remains controversial. The aim of this study was to assess the intervention of fasting in the regulation of anthropometric and metabolic parameters of subjects with overweight or obesity. METHODS The PubMed, Cochrane library, Web of science and EMBASE databases were searched from the inception dates to October 2019, identifying published literature evaluating the effect of fasting intervention on the people with overweight or obesity. RESULTS Twenty-five studies with 1358 participants with overweight or obesity were included in the meta-analysis. Fasting was associated with the significant reduction of body weight, body mass index (BMI), fat free mass (FEM), fat mass (FM), waist circumference (WC), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), systolic blood pressure (SBP) and diastolic blood pressure (DBP). However, there was no significant difference in the variations in the total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), blood glucose and insulin concentrations. CONCLUSION Our meta-analysis found that fasting was associated with a significant effect on the regulation of anthropometric (body weight, BMI, FEM, FM and WC) and metabolic parameters (LDL-C, TG, SBP and DBP) in people with overweight or obesity. Considering some limitations found in this study, additional data from large clinical trials are needed.Since the emergence of transition metal dichalcogenide (TMDC) based van der Waals (vdW) structures, interlayer charge transport has become an important issue towards the application of these novel materials. Due to the unique layered structure of these materials, charge transport across the vdW gaps via tunneling is governed by individual valleys with different interlayer coupling strengths. On the other hand, the omnipresent point defects in TMDCs could possibly cause intervalley scattering between these valleys. In this article, we investigate the influence of point defect induced intervalley scattering on the interlayer charge transport of the MoS2 homojunction by first principles calculation. We find that S vacancies and Mo-S antisite defects enhance the electron interlayer transport by intervalley scattering that divert the electrons from the non-interlayer coupling K valley to the strong interlayer coupling Q valley. The interlayer charge transport enhancement caused by such an intervalley scattering mechanism could pave the way towards understanding the interlayer charge transport in TMDC based vdW structures.C60 fullerene has been utilized in various applications, including low friction and wear coatings, due to its unique molecular structure. In this work, molecular dynamics simulations were conducted to assess the nano-mechanical behaviour of a single C60 fullerene and its crystallized structure. A single C60 model and a model of a face-centred cubic structured C60 crystal with a one-unit-cell thickness were prepared for compression and unloading simulations based on the adaptive intermolecular reactive empirical bond-order potential for carbon. Force-displacement curves and molecule-averaged virial stresses were obtained during the simulation. The models applied during the compression and unloading processes were visualized to confirm the deformation behaviour. Both the single and crystal C60 models showed a perfectly reversible deformation before the point of force decrease that occurred during compression. In particular, the face-centred cubic structure of the crystal C60 model was severely altered during compression before the individual C60 molecules experienced permanent deformation. The maximum values of the normal virial stress in the compression direction before the permanent deformation of the molecules were almost same for both the single and crystallized models.In this paper, we revisit the concepts of the reactivity map and the reactivity bands as an alternative to the use of perturbation theory for the determination of the phase space geometry of chemical reactions. We introduce a reformulated metric, called the asymptotic trajectory indicator, and an efficient algorithm to obtain reactivity boundaries. We demonstrate that this method has sufficient accuracy to reproduce phase space structures such as turnstiles for a 1D model of the isomerization of ketene in an external field. The asymptotic trajectory indicator can be applied to higher dimensional systems coupled to Langevin baths as we demonstrate for a 3D model of the isomerization of ketene.