Growth, asymmetric

Benzylamine Purine. The purine 6-benzylaminopurine [1214-39-7] (13) is an analogue of the natural product adenine, a component of both deoxyribonucleic acid and ribonucleic acid. It is not employed alone, but rather in combination with the natural products GA and GA to improve the size, weight, and thereby, yield per hm of Red DeHcious apples (10,24,25). Compounds with cytokinin activity were reported in 1913 (26) and asymmetric growth in apples was pubHshed in 1968 (27). 

In the second hypothesis there exists a mechanism of asymmetric growth in which, in each propagation step, the conditional probability of a sequence is different from that of its antipode poo Pll)- In this case an asymmetric catalyst (or broadly speaking, a chiral environment) is required whose action persists throughout the whole course of the polymerization. 

There are frequent reports of intrauterine growth retardation, neurobehavioral abnormalities, cerebral injury, and cardiac anomalies in coke babies (SEDA-14,15 SEDA-21,4 SEDA-21, 129) (255,256). Brain hemorrhages (257) and asymmetrical growth retardation (258) associated with maternal cocaine abuse have been discussed. 

In two reports it was suggested that brain hemorrhage (257) and asymmetrical growth retardation (258,270) can occur. 

Little BB, Snell LM. Brain growth among fetuses exposed to cocaine in utero asymmetrical growth retardation. Obstet Gynecol 1991 77(3) 361-4. 

The potential for future asymmetric growth arrest open physis. Because these fractures occur around... 

The detonator bubble sweeping water away from and causing asymmetric growth of the FCI bubble, which would have some undetermined effect on final PAV work. 

Asymmetric Growth and Collapse Periods and Perturbation Area... 

Figure 1.1 Simulation of (a) logistic (symmetrical) and (b) Gompertz (asymmetrical) growth curves. See equations (1.2.5) and (1.2.6), respectively.

The relationship between rotatory power and the degree of polymerization shows that the polymerization initiated by the AlCla-jS-phenylalanine system, which gives the best result, occurs by an asymmetric growth process [199]. Asymmetric induction made possible by the orienting effect of the negative asymmetric counter ion facing the growing end of the polymeric chain and polybenzofuran, can modify, by an autocatalytic behavior. 

The independence of optical rotation of polymer from molecular weight proved the occurrence of asymmetric growth, but in order to determine the extent of asymmetric induction it was necessary to know polymer enantiomeric purity. No detailed investigations have been carried out however, polysorbates and polystyrylacrylate were submitted to oxidative degradation to obtain a conclusive proof of asymmetric induction. Methyl- and phenyl-succinic acid were respectively obtained with optical purity up to 6%... 

Following these theoretical considerations the first asymmetric polymerization of cyclic monomers was performed in the case of benzofuran [71, 72] in the presence of chiral cationic initiators obtained from Lewis acids and optically active Lewis bases (Table XVIII). With AICI3 and j3-phenylalanine the polymer fractions showed essentially constant rotatory power with varying molecular weight, thus indicating an asymmetric growth process. If some polymer is initially present, higher values of asymmetric induction are ob-... 

The preparation of asymmetric nanosilica differs slightly from that of their symmetric counterparts, the main difference being an involvement of templates or anisotropic catalysts [28]. The addition of these materials initiates an asymmetric growth of nanomaterials, thus producing helical nano materials. In the template nanosiUca, a further treatment of as-made silica-like nanomaterials is required to convert them into real siUca nanomaterials. However, in the catalytic growth of heUcal nanomaterials such as nanocoils, no post-synthesis treatment is required. 

Ghostine RA, Markarian MZ, Schlenoff JB (2013) Asymmetric growth in polyelectrolyte multilayers. J Am Chem Soc 135 7636-7646... 

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