Shape transform

Wang Z L ef a/1998 Shape transformations and surface melting of cubic and tetrahedral platinum nanocrystals J. Phys. Chem. B 102 6145... 

In line with the results described so far is a report on the shape transformation of dendrimers that were adsorbed on gold [98]. A transformation from an oblate to a prolate configuration was affected by competitive adsorption of al-kanetiols that reduced the surface area available per dendrimer (Fig. 15). 

All eucaryotic cells contain various proteins in their cytoplasm that interact to form mechanically stabilizing structures. The amounts of these proteins differ with cell type, and the structural elements - collectively referred to as the cytoskeleton -can be very labile. Labile transformations of cytoskeletal networks are involved in such essential biological phenomena as chromosome movement and cell division, intracellular material transport, shape changes relating to tissue development, and amoeboid-like locomotion (1-3). A great deal of work in recent years has led to the biochemical characterization of numerous cytoskeletal proteins(A) and the elucidation of their spatial localization within a cell(2). However, few quantifiable models yet exist that are appropriate for incorporating that information into notions of shape transformation and cell movement(5-8). 

In other words, the desired property is obtained by multiplying each structure factor in the conventional summation by the Fourier transform of the operator, integrated over the volume element of interest. For the net charge, the operator 0=1, and the integral is referred to as the shape transform of the volume of integration. 

For the higher moments, s, depends on the location of the subunit i. But in the case of the net charge, all s, are equal, provided the subunits have identical shape. When the subunits are parallelepipeds with edges of length 2dx, 25y, and 2dz parallel to the crystallographic axes, as in Fig. 6.4, the shape transform of the subunit, s0(H), is of a particularly simple form (Weiss 1966, Coppens and Hamilton 1968) ... 

Voxel-Based Morphometric Analysis Using Shape Transformations Christos Davatzikos... 

Since the electron density distributions in the different spaces separated by the membranes are similar across the very different membrane topologies, there is little doubt that shape transformations of the membrane occur through intersection-free membrane folding. The work by G.W. Anderson and... 

Crystallite shape transformations, due to adsorbed reactants, may affect the steady-state kinetics of catalytic reactions. Such effects can be studied phenomenologically by employing the Wulff rule [39] in order to find the optimum crystallite shape. The use of this rule implies that the crystallite reshaping time scale is shorter than the experimental time scale. The latter can be very long in practical systems. 

Peterlin, P., Arrigler, V., Kogej, K., Svetina, S., and Walde, P. (2009) Growth and shape transformations of giant phospholipid vesicles upon interaction with an aqueous oleic acid suspension. Chemistry and Physics of Lipids, 159 (2), 67-76. 

Figure 4. Spherical shape transformation of granular minerals in hot gas streams A, illite B, muscovite C, native quartz D, chlorite. Reproduced with permission from reference 2. Copyright 1985 Itemisphere Publishing Corp.

Sprandel U. Temperature-induced shape transformation of carrier erythrocytes. Res Exp Med 1990 190 267-275. 

Unfortunately, there are only few data available describing the effects of ethanol on conventional liposomes composed of molecules with mixed-chain fatty acids, such as POPC. The few permeability studies seem to demonstrate that the effect of ethanol on such liposomes might be low. And with GVs, there is (to the best of my knowledge) only one study that has been published demonstrating the effect of ethanol on the GV bilayers. In this study it was shown that high concentrations of ethanol induce shape transformations of GV formed by electroformation and it was assumed that the stability of these GVs might be negatively influenced. 

Angelova, M.I. et al.. Shape transformations of giant unilamellar vesicles induced by ethanol and... 

Besides issues related to the accuracy of force fields in spatially inhomogeneous systems comprising many chemically distinct components, the basic restriction related to the chemically detailed models is the rather small length and time scales that they can access. This limitation imposes severe restrictions for considering collective phenomena in amphiphilic vesicles, i.e., processes that involve large particle numbers. Typical examples include vesicle assembly, vesicle fusion, phase separation and shape transformations of multicomponent amphiphilic vesicles. For many of these processes, it is expected that the underlying atomistic details of the molecular constituents can be captured by a small number of relevant characteristics and universality classes, comprised of systems with a rather different atomistic structure, can be identified. These phenomena can be successfully investigated via minimal... 

We have only dealt with the main chain nematic networks so far. Actually many liquid crystalline networks are formed by crosslinking the backbones of side chain liquid crystalline polymers. The side chain nematic polymers have three nematic phases and their backbones have either prolate or oblate conformations, depending on their phase. It is expected that the rubber elasticity of a side chain nematic polymer network is more complex. For instance, the stress-induced Ni-Nm phase transition is predicted as the network shape transforms from oblate to prolate. Liquid crystalline networks have a bright potential in industry. 

It should also be mentioned, that crystallite shape transformations due to adsorbed reactants may affect the steady-state kinetics of catalytic reactions. 

The Ge deposition was carried out at tenqieratures of 550 and 600 °C. The choice of such temperatures was guided by the fact that in this temperature range the islands in a single layer exhibit a dome shape, a point which is crucial for the study of the island shape transformation and will be discussed below. The Ge growth rate is about 1.5 monolayers (ML) per min. The Si deposition was carried out at 600 °C with a growth rate of about 2.5 nm per min. 

Shape Transformations of Giant Vesicles Extreme Sensitivity to Bilayer Asymmetry. 

Similarly to the case of non-ionic micelles, micelles with a charged corona can demonstrate shape transformations. The physical origin of these morphology... 

We next cut out the lenticular primordial material from the large external sheet and set it aside, leaving the sheet with an elliptical cavity having the same shape as depicted in Fig. 11.7, and then let it undergo an extensional shape transformation in the y direction equal to the extension ratio of the craze matter for it to acquire a shape... 

Hu M, de Jong DH, Marrink SJ, Desemo M (2013) Gaussian curvature elasticity determined from global shape transformations and local stress distributions a comparative study using the MARTINI model. Farad Discuss 161 365-382... 

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