Overgrowth

Actual crystal planes tend to be incomplete and imperfect in many ways. Nonequilibrium surface stresses may be relieved by surface imperfections such as overgrowths, incomplete planes, steps, and dislocations (see below) as illustrated in Fig. VII-5 [98, 99]. The distribution of such features depends on the past history of the material, including the presence of adsorbing impurities [100]. Finally, for sufficiently small crystals (1-10 nm in dimension), quantum-mechanical effects may alter various physical (e.g., optical) properties [101]. 

The oriented overgrowth of a crystalline phase on the surface of a substrate that is also crystalline is called epitaxial growth [104]. Usually it is required that the lattices of the two crystalline phases match, and it can be a rather complicated process [105]. Some new applications enlist amorphous substrates or grow new phases on a surface with a rather poor lattice match. 

Oriented ultrathin overgrowth of a polymer on a non-polymeric substrate is the latest combination of materials to show epitaxy. The most recent, remarkable form of this phenomenon is the formation of an array of parallel polymer chains on a substrate by depositing monomers and then polymerising them in situ. The Japanese discoverer of this phenomenon (Sano 1996) has called it polymerisation-induced... 

PTEN Cowden disease, Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, Lhermitte-Duclos disease overgrowths of various organs, hamartomas of the skin, mucosa, cerebellar cortex high risk of developing several types of cancer. Spontaneous pten mutations found frequently in human cancers... 

Intuitively it might be supposed that a poljrmer with a hydrophilic surface might be more biocompatible than one with a ("foreign ) hydrophobic surface. This simple interpretation is not always correct. Nevertheless, the study of hydrophilic polymers, especially those that promote endothelial tissue overgrowth or ingrowth, is an area of great interest. 

The zeohte overgrowth has been reported for FAU on EMT zeohte [44] and MCM-41 on FAU zeohte [45]. On the other hand, in this study, zeohte layers were grown on the zeohte with the same framework structure, resulting in high coverage of ZSM-5 crystals with silicalite layers and high para-selectivity. The zeohte crystals with oriented thin layer on their external surface are expected to form a new class of shape-selective catalysts. 

The most serious and life-threatening complication is recurrent pulmonary infections due to overgrowth of various pathogens in the viscous secretions of the respi-... 

Delays of more than two hours after the collection is completed may lead to markedly erroneous results. Urines with bacterial overgrowth, hemolyzed blood, or those obtained following any type of instrumental examination of the urinary tract may also lead to erroneous results, and should not be used for assays of enzyme activities. The stability of some clinically important enzymes in the various body fluids is given in Table IV. 

Terry, T.L. (1942). Extreme prematurity and fibroblastic overgrowth of persistent vascular sheath behind each crystalline lens. 1. Preliminary reports. Am J. Ophthalmol. 25, 203-243. 

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