查看更多>>摘要：Abstract Living cells actively deform and move by their force generations in three-dimensional (3D) space. These 3D cell dynamics occur over a long-term time scale, ranging from tens of minutes to days. On such a time scale, turnover of cell membrane constituents due to endocytosis and exocytosis cannot be ignored, i.e., the surface membrane dynamically deforms without mass conservation. Although membrane turnover is essential for large deformation of cells, there is no computational framework yet to simulate long-term cell dynamics with a non-conservative fluidic membrane. In this paper, we proposed a computational framework for simulating the long-term dynamics of a cell membrane in 3D space. For this purpose, in the proposed framework, the cell surface membrane is treated as a viscous fluid membrane without mass conservation. Cell shape is discretized by a triangular mesh, and its dynamics are expressed by effective energy and dissipation function. The mesh structure, distorted by membrane motion, is dynamically optimized by introducing a modified dynamic remeshing method. To validate the proposed framework, numerical simulations were performed, showing that the membrane flow is reproduced in a physically consistent manner and that the artificial effects of the remeshing method were negligible. To further demonstrate the applicability of the proposed framework, numerical simulations of cell migration induced by a mechanism similar to the Marangoni effect, i.e., the polarized surface tension actively generated by the cell, were performed. The observed cell behaviors agreed with existing analytical solutions, indicating that the proposed computational framework can quantitatively reproduce long-term active cell dynamics with membrane turnover. Based on the simple description of cell membrane dynamics, this framework provides a useful basis for analyzing various cell shaping and movement.Graphical abstract
查看更多>>摘要：Abstract The report presents experimental results, which can be considered as the reference for innovative generations of supercritical fluids (SCF), liquid–liquid (LL), and liquid (L) extraction technologies. They are related to implementations of Critical Phenomena Physics, for such applications not considered so far. For the gas–liquid critical point, the shift SuperCritical Fluids (SCF) ? SubCritical Fluids, due to the additional exogenic impact of ultrasounds, is indicated. For LL technology, the possibility of increasing process effectiveness when operating near the critical consolute under pressure is indicated. Finally, the discovery of long-range precritical-type changes of dielectric constant in linseed oil, standing even 50?K above the melting temperature, is presented. It suggests that extraction processes linking ‘SCF’ and ‘L’ technologies features and exploring the natural carrier, such as linseed oil, are possible. The report recalls the fundamental base for extraction processes via Kirkwood and Noyes–Whitney relations and presents their implementations to ‘critical conditions,’ including pressure. Graphical abstract
查看更多>>摘要：Abstract We compute the roughness exponent of the averaged contact line width of a liquid on heterogeneous substrates with randomly distributed dilute defects in statics. We study the case of circular “mesa”-type defects placed on homogeneous base. The shape of the liquid meniscus and the contact line are obtained numerically, using the full capillary model when a vertical solid plate, partially dipped in a tank of liquid, is slowly withdrawing from the liquid. The obtained results imply that the contact line roughness exponent depends on the contact angle θ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\theta $$\end{document}, which the liquid meniscus forms with the solid homogeneous base. The roughness exponent grows when |θ-90°|\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ |\theta - 90^{\circ } |$$\end{document} decreases, and it changes from 0.5 at |θ-90°|=70°\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$|\theta - 90^{\circ } |= 70^{\circ }$$\end{document} to 0.67 at |θ-90°|=0°\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$|\theta - 90^{\circ } |= 0^{\circ }$$\end{document}. A wide range of contact angles (60°\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$60^{\circ }$$\end{document}–107.5°\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$107.5^{\circ }$$\end{document}) is present, where the roughness exponent is practically constant, equal to previously obtained experimental results on the magnitude of the roughness exponent and its dependence on θ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\theta $$\end{document}.Graphic abstract
Szpakiewicz-Szatan AleksanderRzoska Sylwester J.Drozd-Rzoska Aleksandra
5页
查看更多>>摘要：Abstract Melting/freezing are canonical examples of discontinuous phase transitions, for which no pretransitional effects in the liquid phase are expected. For the solid phase, weak premelting effects are evidenced. This report shows long-range, critical-like, pretransitional effects in liquid thymol detected in electrooptic Kerr effect (EKE) studies. Notably is the negative sign of EKE pretransitional anomaly. Studies are supplemented by the high-resolution dielectric constant temperature-related scan, which revealed a weak premelting effect in the solid phase. Both EKE and dielectric constant show a ‘crossover’ change in the liquid phase, ca, 10?K above the freezing temperature. It can be recognized as the hallmark of the challenging liquid–liquid transition phenomenon.Graphical abstract
查看更多>>摘要：Abstract Focusing on non-ergodic macroscopic systems, we reconsider the variances δO2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\delta \mathcal{O}^2$$\end{document} of time averages O[x]\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathcal{O}[\mathbf {x}]$$\end{document} of time-series x\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathbf {x}$$\end{document}. The total variance δOtot2=δOint2+δOext2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\delta \mathcal{O}^2_{\mathrm {tot}}= \delta \mathcal{O}^2_{\mathrm {int}}+ \delta \mathcal{O}^2_{\mathrm {ext}}$$\end{document} (direct average over all time series) is known to be the sum of an internal variance δOint2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\delta \mathcal{O}^2_{\mathrm {int}}$$\end{document} (fluctuations within the meta-basins) and an external variance δOext2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\delta \mathcal{O}^2_{\mathrm {ext}}$$\end{document} (fluctuations between meta-basins). It is shown that whenever O[x]\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathcal{O}[\mathbf {x}]$$\end{document} can be expressed as a volume average of a local field Or\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathcal{O}_{\mathbf{r}}$$\end{document} the three variances can be written as volume averages of correlation functions Ctot(r)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$C_{\mathrm {tot}}(\mathbf{r})$$\end{document}, Cint(r)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$C_{\mathrm {int}}(\mathbf{r})$$\end{document} and Cext(r)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$C_{\mathrm {ext}}(\mathbf{r})$$\end{document} with Ctot(r)=Cint(r)+Cext(r)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$C_{\mathrm {tot}}(\mathbf{r}) = C_{\mathrm {int}}(\mathbf{r}) + C_{\mathrm {ext}}(\mathbf{r})$$\end{do
查看更多>>摘要：Abstract The ongoing coronavirus disease 2019 (COVID-19) pandemic poses a major threat to the worldwide health care. In this context, epidemic modelling is an integral part of containment strategies. Compartmental models are typically used for this purpose. Analytical solutions of the two distinct but connected Susceptible-Infectious-Recovered-Deceased (SIRD) and Susceptible-Infectious-Quarantine-Recovered (SIQR) models are presented in this study. Furthermore, the behaviour at the start of a disease outbreak is derived. This analysis shows that a combination of transmission, recovery and isolation rates dominates the behaviour at the start of an epidemic. In addition, the loss occurring due to quarantine and lockdown measures is investigated, where it can be observed that quarantine procedures lead to a smaller loss in comparison with lockdown regulations. Within this framework, optimized strategies that lead to a constant epidemic peak or a minimized loss are presented.
查看更多>>摘要：Abstract The tendency to crystallize was studied in the selected monohydroxy alcohols: 1-chloro-2-methyl-2-propanol, 1-chloro-2-propanol, 3-chloro-1-propanol, and 8-chloro-1-octanol. Performed calorimetric measurements have proved that the differences in structures of tested alcohols influence the tendency to crystallization. At a sufficiently fast heating rate, no crystallization was observed in the case of 1-chloro-2-propanol and 3-chloro-1-propanol, contrary to other two alcohols. The obtained results suggest that elongation of the alkyl chain or adding a methyl group to the hydrocarbon backbone increases the susceptibility to crystallization.Graphical abstract
查看更多>>摘要：Abstract We consider history-dependent behavior in domain-type configurations in orientational order that are formed in configurations reached via continuous symmetry-breaking phase transitions. In equilibrium, these systems exhibit in absence of impurities a spatially homogeneous order. We focus on cases where domains are formed via (i) Kibble-Zurek mechanism in fast enough quenches or by (ii) Kibble mechanism in strongly supercooled phases. In both cases, domains could be arrested due to pinned topological defects that are formed at domain walls. In systems exhibiting polar or quadrupolar order, point and line defects (disclinations) dominate, respectively. In particular, the disclinations could form complex entangled structures and are more efficient in stabilizing domains. Domain patterns formed by fast quenches could be arrested by impurities imposing a strong enough random-field type disorder, as suggested by the Imry-Ma theorem. On the other hand, domains formed in supercooled systems could be also formed if large enough energy barriers arresting domains are established due to large enough systems’ stiffness. The resulting effective interactions in established domain-type patterns could be described by random matrices. The resulting eigenvectors reveal expected structural excitations formed in such structures. The most important role is commonly played by the random matrix largest eigenvector. Qualitatively different behavior is expected if this eigenvector exhibits a localized or extended character. In the former case, one expects a gradual, non-critical-type transition into a glass-type structure. However, in the latter case, a critical-like phase behavior could be observed.Graphical abstract
NSTL
Springer Nature