Analytical solution of problem of shielding low-frequency magnetic field by thin-walled cylindrical screen in presence of cylinder

The analytical solution of boundary value problem describing the process of penetration of low-frequency magnetic field through thin-walled cylindrical screen with cylindrical inclusion is constructed by use of approximate boundary conditions. The source of the field is a thin thread of infinitely small length with an infinitely small cross-section where current circulates. Thread is located in a plane which is perpendicular to axis of cylindrical screen, in outer region with respect to a screen. Initially the potential of initial magnetic field is represented as spherical harmonic functions, then using addition theorems connecting spherical and cylindrical harmonic functions, it became as cylindrical harmonic functions superposition. Secondary potentials of magnetic field are also presented as superposition of cylindrical harmonic functions in three-dimensional space. It is shown that the solution of formulated boundary value problem is reduced to the solution of linear algebraic equations system for coefficients included in the representation of secondary fields. The influence of some aspects of the problem on the value of the screening coefficient of an external magnetic field when passing through a cylindrical copper screen in the presence of a cylindrical inclusion is studied numerically. Calculation results are presented in graphs form. Obtained results can be used to shield technical devices and biological objects against the effects of magnetic fields to provide ecological surrounding of operating electrical installations and devices.

Scattering of SH Waves by a Partially Debonded Cylindrical Inclusion in the Covering Layer

This article presents analytical solutions to the problem of dynamic stress concentration and the surface displacement of a partially debonded cylindrical inclusion in the covering layer under the action of a steady-state horizontally polarized shear wave (SH wave); these solutions are using the complex function method and wave function expansion method. By applying the large-arc assumption method, the straight line boundary of the half-space covering layer is transformed into a curved boundary. The wave field of the debonded inclusion is constructed utilizing a Fourier series and boundary conditions of continuity. The impact of debonding upon the dynamic stress concentration and surface displacement around the cylindrical concrete or steel inclusion is analyzed through numerical examples of the SH waves that are incident at normal angles, from a harder medium to a softer medium and from a softer medium to a harder medium. The examples show that various factors (including the medium parameters of the soil layers and the inclusion, the frequency of the incident waves, and the debonding situations) jointly affect the dynamic stress concentration factor and the surface displacement around the structure.

Cylindrical Inclusion Protein of Wheat Yellow Mosaic Virus Is Involved in Differential Infection of Wheat Cultivars

Wheat yellow mosaic virus (WYMV) belongs to the genus Bymovirus in the family Potyviridae and has a bipartite genome (RNA1 and RNA2). WYMV in Japan is classified into three pathotypes (I to III) based on its pathogenicity to wheat cultivars. Among these three, pathotypes I and II are discriminated by their pathogenicity to the wheat cultivar Fukuho; pathotype I infects Fukuho but pathotype II does not. In the present study, the genomic regions that are involved in such pathogenicity were examined using infectious viral cDNA clones of pathotypes I and II. Reassortant experiments between viral RNA1 and RNA2 revealed the presence of a viral factor related to pathogenicity in RNA1. A chimeric pathotype II virus harboring a cylindrical inclusion (CI) cistron from pathotype I facilitated systemic infection of Fukuho, indicating that CI protein is involved in pathogenicity. Furthermore, analysis of chimeric and site-directed mutants revealed that three amino acids at the N-terminal region of CI protein were involved in pathogenicity to Fukuho. On the other hand, at the single-cell level, pathotype II replicated in protoplasts of Fukuho similar to that of pathotype I virus. These data suggest that differential pathogenicity between pathotypes I and II was considered to depend on the ability of cell-to-cell or long-distance viral movement, in which CI protein is involved. To the best of our knowledge, this is the first report to show the involvement of the bymoviral CI protein in pathogenicity.

Green’s Function and Eshelby’s Tensor Based on Mindlin’s 2nd Gradient Model: An Explicit Study of Cylindrical Inclusion Case

Based on Mindlin’s 2nd gradient model that involves two length-scale parameters, Green’s function, Eshelby tensor and Eshelby-like tensor for an inclusion of arbitrary shape are derived. It is proved that the Eshelby tensor consists of two parts: the classical Eshelby tensor and a gradient part including the length-scale parameters, which enable the interpretation of the size effect. When the strain gradient is not taken into account, the obtained Green’s function and Eshelby tensor reduce to its analogue based on the classical elasticity. For the cylindrical inclusion case, the Eshelby tensor in and outside the inclusion, the volume average of the gradient part and the Eshelby-like tensor are explicitly obtained. Unlike the classical Eshelby tensor, the results show that the components of the new Eshelby tensor vary with the position and the inclusion dimensions. It is demonstrated that the contribution of the gradient part should not be neglected.