Y-branch structures

Murphy, W. J., Watkins, K. P. and Agabian, N. (1986) Identification of a novel Y branch structure as an intermediate in trypanosome mRNA processing evidence for trans-splicing. Cell 47 517-525. 

To make the above discussion more concrete, consider the example branching structure of Fig. 3. In this structure, we have identified an x and y, which have the same objective function values, and their ancestors, (x, y) which are characterized by the same set of symbols, (i.e., batches). Furthermore, we can see that the children of x,y do indeed satisfy the requirements of Condition-a and Condition-b and hence, (x, y) would be considered as candidates to develop a new equivalence relationship. If we examine the partial schedules (x, y) as depicted in Fig. 6, our knowledge... 

Alternatively, the structural units of the polymer may be connected together in such a manner as to form nonlinear, or branched, structures of one sort or another. Some, at least, of the structural units must then possess a valency greater than two. A typical nonlinear pol3oner structure in which the branching units represented by Y are trivalent may be indicated as follows ... 

If both X and Y are alkyl groups, the reference compound is a singly branched hydrocarbon, and it is converted to a doubly branched structural unit in the hypothetical dehydrogenation process hence... 

Yoshikawa Y, Ofuji N, Imaizumi M, Moteki Y, Fujimaki T (1996) Molecular weight distribution and branched structure of biodegradable aliphatic polyesters determined by s.e.c-MALLS. Polymer 37 1281... 

Sakata, T, Okabe, K. and Kuwahara, Y. (2001). Structure elucidation of twelve novel esters between five fatty acids and three branched new alcohols along with four monoterpenoids from Sancassania shanghaiensis (Acari Acaridae). Bioscience, Biotechnology and Biochemistry 65 919-927. 

Metzger, P., Casadevall, E., Pouet, M. J. and Pouet, Y. (1985). Structures of some botryococcenes branched hydrocarbons from the B-race of the green alga Botryococcus braunii. Phytochemistry, 24,2995-3002. 

Lifshitz-van der Waals portion (/jf). Straight-chain structures improve the chances for intermolecular interactions of the Lifshitz-van der Waals type [13], On the other hand we assume that only one of the two oxygen atoms of the straight-chain trisiloxanyl moiety is sufficiently close to the water surface to influence the donor-acceptor portion. As to expect from the results for pure liquids only donor-acceptor portions fj/ were detected at the interface solid/liquid. The values are identical to those for indicating a common source for the donor-acceptor portions The increased y l value for the branched structure 3 indicates that in this particular case both oxygen atoms are exposed to the perfluorinated surface. 

Macak. P.. Luo. Y., Norman. P.. Agren, H. Electronic and vibronic contributions to two-photon absorption of molecules with multi-branched structures. J. Chem. Phys. 113, 7055-7061 (2000)... 

The results shown in Table III demonstrate that when HTC is irradiated in the molten state both H-links and Y branches as well as cis and trans double bonds are formed. In contrast, irradiation at room temperature produces principally trans double bonds. The linked structures formed during melt irradiation are present in reasonably comparable amounts. The number of saturated end groups, as determined by spectral integration, was not significantly affected by irradiations to 100 Mrad in either the molten or solid state. Finally, it should be pointed out that the radiation yields for structures produced by a 100 Mrad irradiation of HTC are quite low. The G values for the most abundant radiation products are less than one. 

Results of measurements on a sample of NBS 1475 irradiated to 8.0 Mrad in vacuum at 300 K are also shown in Table VI. The spectrum from which these data were obtained is shown in Figure 12. This experiment was the only one performed in this study where the gel dose was exceeded. An attempt was made to dissolve the entire sample in 1,2,4-trichlorobenzene but only a clear swollen gel was the result. The subsequent 13c NMR spectrum indicated that only the mobile, soluble component produced observable resonances. The only significant structural unit identified in the soluble component was trans double bonds a trace amount of long chain Y branches was also observed, but H-links could not be detected in the soluble fraction. 

To complete the specification of the algorithm, we require one additional decision parameter how to select the next problem Y(x), which we will solve, or equivalently, which node in the branching structure to expand. We will define a search function, s, which allows us to select a node from the currently unexpanded nodes for expansion. In this chapter, as in Ibaraki (1978), we consider only best bound search, where we select the node with the minimum g(x) value for expansion. Thus our branch-and-bound algorithm, A, is explicitly specified by... 

Figure 6.2 Formation pathway of the carboxylic branching structure and its characteristic product (compound Y) for the thermally treated FR-PC. Reproduced with permission from K. Fiayashida, Fi. Ohtani, S. Tsuge and K. Nakanishi, Polymer Bulletin, 2002, 48, 483. 2002, Springer [47]...

Zheng, Y. Thurecht, K. J. Wang, W., Polysiloxanes Polymers with Hyper-branched Structure and Multivinyl Functionality. J Polym. Sci Pol Chem 2012, 50(4), 629-637. 

Systematic investigations give evidence that homooligopeptides consisting of amino acids with linear side chains tend to adopt the antiparallel P-structure. Homooligomers with P-branched and aromatic residues, e.g. [L-Phe] and [L-Tyr(Bzl)] predominantly prefer the parallel P-sheet type [L-Leu] with y-branched amino acids was shown to adopt both of these structural variants... 

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