The European Physical Journal E最新文献

Molecular descriptors encapsulate the key structural information of molecules, which is crucial for elucidating molecular behaviors. They have proven invaluable in quantitative structure–property relationship (QSPR) analysis. Such studies involve rigorous scientific investigations into the relationship between molecular structure and diverse physicochemical properties, revealing the underlying principles governing structure–property correlations. This facilitates predictive modeling and rational design across a wide range of scientific disciplines. Cancer is a lethal disease characterized by the uncontrolled growth and spread of abnormal cells. This study aims to develop regression models for predicting physicochemical properties of novel anti-cancer drugs targeting blood and skin cancers. Utilizing distance-based indices, we construct models based on the structural properties of drug compounds. Comparative analysis with existing QSPR models employing degree and reverse degree parameters demonstrates significantly enhanced predictive capabilities of our proposed models.

A compact analytical form is derived through an integration approach for the interaction between a sphere and a thin rod of finite and infinite lengths, with each object treated as a continuous medium of material points interacting by the Lennard-Jones 12-6 potential and the total interaction potential as a summation of the pairwise potential between material points on the two objects. Expressions for the resultant force and torque are obtained. Various asymptotic limits of the analytical sphere–rod potential are discussed. The integrated potential is applied to investigate the adhesion between a sphere and a thin rod. When the rod is sufficiently long and the sphere sufficiently large, the equilibrium separation between the two (defined as the distance from the center of the sphere to the axis of the rod) is found to be well approximated as (a+0.787sigma ), where a is the radius of the sphere and (sigma ) is the unit of length of the Lennard–Jones potential. Furthermore, the adhesion between the two is found to scale with (sqrt{a}).

The topical issue titled “Charged Species in Bulk and at Interfaces: Interaction, Mobility, Transport, and Regulation” is based on contributions from speakers at three CECAM workshops held in 2016, 2018, and 2022. In addition, this editorial is also intended to express our sincere appreciation to our senior co-organizers, Prof. Jan K. G. Dhont (FZJ, Germany) and Prof. Gerhard Kahl (TU Wien, Austria), for their invaluable contributions.

This study extends the Lucas–Washburn theory through non-equilibrium thermodynamic analysis to examine fluid absorption in medical foams used for hemorrhage control. As a universal model for capillary flow in porous media, the theory demonstrated strong agreement with experimental results, confirming its semi-quantitative accuracy. Minor deviations, likely due to material heterogeneity, were observed and explained, enhancing the theory’s applicability to real-world conditions. Our findings underscore the universality of the Lucas–Washburn framework and provide valuable insights for optimizing the design of medical foams, ultimately contributing to more effective bleeding control solutions in clinical applications.

In the past years, the amount of research on active matter has grown extremely rapidly, a fact that is reflected in particular by the existence of more than 1000 reviews on this topic. Moreover, the field has become very diverse, ranging from theoretical studies of the statistical mechanics of active particles to applied work on medical applications of microrobots and from biological systems to artificial swimmers. This makes it very difficult to get an overview over the field as a whole. Here, we provide such an overview in the form of a metareview article that surveys the existing review articles and books on active matter. Thereby, this article provides a useful starting point for finding literature about a specific topic.

We analyze the macroscopic dynamics of antiferroelectric smectic (Z_textrm{A}) and antiferromagnetic smectic (Z_textrm{M}) liquid crystals. The smectic (Z_textrm{A}) phase is characterized by antiferroelectric order in one direction in the planes of the smectic layers giving rise to an orthogonal biaxial overall symmetry without polar direction. Thus in sufficiently thick (bulk) samples without externally applied electric fields, globally (D_{2h}) symmetry results. Therefore, the macroscopic dynamics of the smectic (Z_textrm{A}) is isomorphic to that of the McMillan phase and one can take over the corresponding results in the field-free limit. This also applies to the defect structure in the sense that one can expect the appearance of half-integer defects as they have also been observed for the McMillan phase. Based on the fact that ferromagnetic nematic liquid crystals are known for about a decade, it seems natural to investigate the antiferromagnetic analog of the smectic (Z_textrm{A}) phase, which we denote as (Z_textrm{M}) in the present paper. In this phase, one also has an in-plane preferred direction, which is, however, not like a director in an ordinary nematic, but odd under time reversal. It can be characterized by a staggered magnetization, ({varvec{N}}), just as in a solid antiferromagnet like MnO. As additional macroscopic variables when compared to a usual non-polar smectic A phase, we have the in-plane staggered magnetization and the magnetization ({varvec{M}}). As a consequence, we find that spin waves (frequently called anti-magnons in solids) become possible. Therefore, we have for the antiferromagnetic smectic phase, (Z_textrm{M}), three pairs of propagating modes: first and ‘second’ sound as in usual smectic A phases and one pair of spin waves. The coupling between ‘second’ sound and spin waves is also analyzed leading to the possibility to excite spin waves by dynamic layer compressions and, vice versa, to generate ‘second’ sound by temporally varying magnetic fields. We note, however, that without additional mechanical or magnetic deformations, the coupling between spin waves on the one hand and first and second sound on the other is a higher order effect in the wave vector (textbf{q} ). We also analyze the question of antiferroelectricity and antiferromagnetism for nematic liquid crystals.

The inverse sum indeg index of a given graph G is symbolized with ISI and defined by sum of the weights (frac{d_u d_v}{d_u + d_v}) entire links (uvin G). We denote (d_u) (resp. (d_v)) the degree of a vertex u (resp. v) of G. In this paper, we obtained the sharp lower bound of tricyclic graphs with respect to the ISI index of order (ngeqslant 6) with size (n + 2). By using atoms as vertices and chemical bonds as edges, graph theory permits the representation of molecular structures as mathematical entities called graphs. Based on the above concept, we formulated the ISI index of octane isomers (OI) and benzenoid hydrocarbons (BH) and compared the values of ISI index with various degree-based TI’s via their correlations and chemical properties. The structural analysis of octane isomers is an important application of this research, as the ISI index delivers insights into stability designs across various isomeric forms.