Bundle nucleus

It is interesting to clarify what kind of molecular structure of end surface of polymer crystals corresponds to small and large <7eS of nano-nucleus and macro-crystal of polymers, respectively. However, the size of also affects the end structures. Figure 4.7 shows that the nano-nucleus will form a loosely folded or bundle nucleus as Price predicted [12], In the case of a loosely folded or bundle type nano-nucleus (small N), the chain density on the end surface is small and not overcrowded. In the case of a fold type nano-nucleus, the energy required to form sharp folds is very large because one fold of PE has to have three gauche bonds [28]. Therefore, (Te (loose fold or bundle) is much smaller than... 

Figure 4.7 Schematic illustration of against N. The nano-nucleus should form a loose fold or bundle nucleus as Price showed [12] because the energy to form sharp folds is very large. The macro-crystal tends to form sharp folds [29]. Therefore, cTe(expected) shows the size dependence of expected a. (See color insert.)...

Fig. 9.36 Schematic representation of Gibbs type nucleus of long chain molecules, (a) Bundle nucleus, f is thickness of nucleus (b) regularly folded chain, adjacent re-entry nucleus. I is thickness of nucleus.

In the bundle-like nucleation, there are two possibilities one is the attachment of a whole molecule to the crystal substrate and the other is the attachment of part of a molecule to the substrate. For long molecules, the former situation is unfavorable because of the high free energy created on forming a thick nucleus. It would be reasonable to consider that each molecule is partially incorporated into the crystal substrate. This bundle-like nucleation can be expressed by the model shown in Fig. 14. 

Figure 13 Schematic diagram of the dependence of <7 on pressure. (F) Denotes folded-chain nucleus, (B) denotes bundle-like nucleus and (B ) denotes addition of ethyl cellulose liquid crystal polymer. (From Refs. 104, 110, 111, and 117.)...

Figure 14 Model of monomolecular growth of bundle-like nucleus. (From Refs. 104, 110, and 111.)...

According to Flory [121], Mandelkern [122], and Price [123], the free energy change in the formation of a bundle-like nucleus shown in Fig. 14 can be expressed as ... 

In Eq. (12), the fourth term results from the increased volume available to the ends of the polymer chains on melting and the fifth term results mainly from the requirement that the ends of the molecules should stay out of the crystallites. Both terms are entropy terms giving the molecular weight dependence of the formation of bundle-like nucleus. Thus, the net transition rate J can be determined by the following equations ... 

Figure 7.1 Dopamine neuronal pathways. AMYG, amygdala CN, caudate nucleus MFB, medial forebrain bundle NcA, nucleus accumbers OT, olfactory tubercle PUT, putamen SN, substantia nigra. For full details see text and Moore and Bloom (1978) and Lindvall and Bjorkland (1978)...

An extra-bulbar olfactory pathway (EBOP) is present in teleosts and in some non-teleost genera. Olfactory fibres run within the medial forebrain bundle, and can be traced (by SBA lectin binding) beyond the olfactory bulb into areas such as the ventral telencephalon, and/or the preoptic nucleus (Hofmann and Meyer, 1995). The projection of the EBOP fibres is similar in the sturgeon, but in other non-teleosts the primary olfactory fibres reach diencephalic target nuclei. 

The nucleus contains bundles of a fibrous material known as chromatin, which is made up of mixed proteins and deoxyribonucleic acid (DNA), the substance that carries the genetic information of the living organism of which the cell is a component. All cells replicate by division. When a cell replicates, DNA in the chromatin of the nucleus passes the genetic information from one generation to the next one. As the cell divides, the chromatin clusters into rodlike structures known as chromo-... 

Fig. 11.5 (a) Confocal microscope image of HMMs exposed to AgI SWNT at 3 days confirming inclusion of SWNT bundles inside the nucleus (blue), (b) HAADF-STEM image of PbO SWNTs crossing the nuclear membrane into the nucleus (inset from boxed region A) (40 nm thick section, unstained) (See Color Plates)... 

Fig. 16.2 Schematic representation of cellular and artificial membrane nanotubes. (A) Two cells are connected by a tunneling nanotube (arrowhead) containing a bundle of filamentous actin (red line). N (grey), nucleus M (purple), mitochondrium ER (green), endoplasmic reticulum G (blue), Golgi apparatus. (B) Lipid nanotube connecting two lipid vesicles formed by pulling a membrane tether. (C) Membrane tether pulled from the plasma membrane of a cell (see Color Plates)...

Forehmin frontal cortex olfactory nucleus nucleus accumbens septal area amygdala hypothalamus entorhinal cortex caudate nucleus entopeduncular nucleus hippocampus ventral and medial thalamus median forebrain bundle dorsal noradrenergic bundle... 

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