Analytical approach for collective diffusion: One-dimensional homogeneous lattice

2014 ◽  
Vol 141 (3) ◽  
pp. 034117 ◽  
Author(s):  
Alexander Tarasenko
Author(s):  
Emilio Acerbi ◽  
Domenico Mucci

We consider the total curvature of graphs of curves in high-codimension Euclidean space. We introduce the corresponding relaxed energy functional and prove an explicit representation formula. In the case of continuous Cartesian curves, i.e. of graphs cu of continuous functions u on an interval, we show that the relaxed energy is finite if and only if the curve cu has bounded variation and finite total curvature. In this case, moreover, the total curvature does not depend on the Cantor part of the derivative of u. We treat the wider class of graphs of one-dimensional functions of bounded variation, and we prove that the relaxed energy is given by the sum of the length and total curvature of the new curve obtained by closing the holes in cu generated by jumps of u with vertical segments.


2011 ◽  
Vol 97 (5) ◽  
pp. 717-727 ◽  
Author(s):  
T. Valier-Brasier ◽  
C. Potel ◽  
M. Bruneau ◽  
D. Leduc ◽  
B. Morvan ◽  
...  

A model, presented in a previous paper [J. App. Phys. 108 (2010) 074910], describing the modes coupling due to scattering on small one-dimensional irregularities (parallel ridges) of the surface of isotropic solid plates, when shear horizontal waves polarized along the ridges propagate perpendicularly to them, appears to be a convenient tool to tackle the effects of the shape profile of the ridges (including the depth and the slope). Being concerned by the use of this analytical approach not utilised until now, several results, yet typical of applications, are presented below and compared with some experimental and numerical results, even analytical results (from an alternative analytical model for particular cases). These comparisons permit to highlight the effects of spatial periodicities of the ridges and show that the method could provide information on geometrical parameters characterising the profile of the roughness, which could be of interest when other methods like optical methods cannot be used.


1987 ◽  
Vol 36 (6) ◽  
pp. 3002-3006 ◽  
Author(s):  
Dar̆o Castello ◽  
Alfredo Caro ◽  
Arturo López

1999 ◽  
Vol 337 (3) ◽  
pp. 453-460 ◽  
Author(s):  
Jérôme NIGOU ◽  
Martine GILLERON ◽  
Germain PUZO

Lipoarabinomannans, which exhibit a large spectrum of immunological activities, emerge as the major antigens of mycobacterial envelopes. The lipoarabinomannan structure is based on a phosphatidyl-myo-inositol anchor whose integrity has been shown to be crucial for lipoarabinomannan biological activity and particularly for presentation to CD4/CD8 double-negative αβT cells by CD1 molecules. In this report, an analytical approach was developed for high-resolution 31P-NMR analysis of native, i.e. multiacylated, lipoarabinomannans. The one-dimensional 31P spectrum of cellular lipoarabinomannans, from Mycobacterium bovis Bacillus Calmette–Guérin, exhibited four 31P resonances typifying four types of lipoarabinomannans. Two-dimensional 1H-31P heteronuclear multiple-quantum-correlation/homonuclear Hartmann–Hahn analysis of the native molecules showed that these four types of lipoarabinomannan differed in the number and localization of fatty acids (from 1 to 4) esterifying the anchor. Besides the three acylation sites previously described, i.e. positions 1 and 2 of glycerol and 6 of the mannosyl unit linked to the C-2 of myo-inositol, we demonstrate the existence of a fourth acylation position at the C-3 of myo-inositol. We report here the first structural study of native multiacylated lipoarabinomannans, establishing the structure of the intact phosphatidyl-myo-inositol anchor. Our findings would help gain more understanding of the molecular basis of lipoarabinomannan discrimination in the binding process to CD1 molecules.


Meccanica ◽  
2015 ◽  
Vol 50 (8) ◽  
pp. 1935-1948 ◽  
Author(s):  
Nikita Begun ◽  
Sergey Kryzhevich

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