Morphological hierarchy

Fig.8 Schematic drawing of the morphological hierarchy of a polyethylene spherulite...

Figure 9.2 Illustration of the morphological hierarchy at different length scales in the polyester-clay nanocomposites [4]. Reproduced with permission from Elsevier.

Abstract This chapter gives an overview of the research on the self-assembly of amorphous block copolymers at different levels of hierarchy. Besides the influence of composition and topology on the morphologies of block copolymers with linear, cyclic and branched topologies blends of block copolymers with low molecular weight components, other polymers or block copolymers and nanoparticles will also be presented. 

Since the chain regularity is an attribute of a development of higher levels of structural hierarchy, namely crystalline domains, stereoisomerism affects greatly the morphology and, thus, the mechanical properties of semicrystalline thermoplastics. 

As with many enzymes the role of AMP aminohydrolase in the hierarchy of metabolic catalysts is not clearly understood. Enzymic activity in muscle is markedly reduced in the dystrophic mouse (161, 162), in humans suffering from Duchanne type muscular dystrophy (163), in hypokaliemic periodic paralysis (164), and upon denervation of normal and dystrophic mouse gastronemii (165). Activity is reported to increase in both transplanted and primary hepatomas (151) and in precancerous livers prior to the onset of neoplasia induced by feeding or by intraabdominal injections of the potent carcinogen 3 -methyl-4-dimethyl-aminoazobenzene (166). The weak carcinogen, 4 -methyl-4-dimethyl-aminoazobenzene was not effective (166). Increases in enzyme activity concomitant with altered nuclear-nucleolar morphology, nuclear RNA content, and nuclear RNA biosynthesis were also observed after injections of thioacetamide, a hepatocarcinogen (167, 168). 

Ghiselin, M. T., Summary of our current knowledge of metazoan phylogeny, in The hierarchy of life molecules and morphology in phylogenetic analysis, Fernholm, B., Bremer, K., and Jomvall, H., Eds., Exerpta Medica, Amsterdam, 1989, 261. 

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