Double-strand chain

The native sample E (Fig. 3) contains a relatively large amount of aggregated structures. Most of them appear to rearrange into perfectly matched double-stranded chains after incubation at 80 °C for 2 months (27). This rearrangement is reported to result in a fivefold increase in the apparent viscosity at a shear rate of 1 s-1 (27). A similar rearrangement of xanthan assemblies is also observed in a unpasteurized fermentation broth after exposure of the sample... 

Single or double-stranded chains of nucleic acids ... 

Double-strand chain consisting of an uninterrupted sequence of rings, with adjacent rings having only one atom in common. 

Note A spiro chain is a double-strand chain with adjacent constitutional units joined to each other through three atoms, two on one side and one on the other side of each constitutional unit. 

Both single- and double-stranded chains are found. The most important members of single chains are the pyroxenes including diopside. The most important double-chained minerals are the amphiboles. Some of these contain hydroxyl and fluoride ions, bonded directly to the metal cation and not to the silicon atom. 

LADDER POLYMER. An ordered molecular network of double-stranded chains connected by hydrogen or chemical honds located at regular inicrvals along the chains. Many complex proteins, including DNA. arc of this nature. 

The presence of defects caused by incomplete reaction in the particles has been found while comparing intra- and intermolecular reaction rates in polycomplexes obtained by mixing polymer solutions, and by matrix polymerization 461. In the latter case a polycomplex is formed simultaneously with the chain growth which is connected with the complementary macromolecule, the matrix. This process of polycomplex formation is closer to the equilibrium one — in any case there are considerably fewer obstacles here for forming an uninterrupted sequence of intermolecular bonds. That is why the rate and conversion of thermochemical reactions (which are connected with the presence or absence of defects — loops or tension in double-stranded chains of the polycomplex) depend on how the polycomplex have been obtained. After its destruction and reconstruction (e.g., by increasing and then decreasing of pH in the case of p.c. (PMA — PVPD)) the matrix polycomplex does not differ from the one obtained by mixing 46). 

DNA (deoxyribonucleic acid) The basic genetic material found in all living cells (and some viruses), providing the blueprint (i.e. genes) for construction of proteins. DNA is composed of sugars, phosphates, and bases arranged in a double helix, a double stranded, chain-like molecules composed of nucleotide base pairs. 

Double-stranded chain. This topology is found in [H2N(CH2)2NH2][FeF3S04], II, comprising strictly alternating... 

Up to now, only two one-dimensional zirconium phosphates have been reported. One is [enH2][Zr(HP04)3] [16], and the other is zirconium phosphate fluoride [enH2]i.5[Zr(P04)(HP04)F2] [13] with double-stranded chains. The simple models of one-dimensional chain inorganic polymers are shown schematically in Figure 2. ZrPO-3 has a chain- structure similar to the one-dimensional aluminum phosphate, [A1P208H]2 [29]. 

An alternative approach would generate precursor macromolecules with some disorder of the rigid geometry. A possible way of achieving this is the generation of polymers that have structural units which cause an angular shape of the double-stranded chain. Such precursor polymers then have to be converted into the final ladder macromolecules by means of an elimination or rearrangement step [2, 5]. 

Following recent advances in antibody engineering, it is now possible to s)mthesize humanized antibodies [35]. Because of clinical applicability, antibody-based medicines are one of the biopharmaceutical categories that have attracted close attention in recent years [36]. IgG has been most frequently used for the prevention and treatment of various diseases. The CH2 region of IgG has A-linked carbohydrates (usually complex type double stranded chains) in diverse manners (O Scheme 14). It has recently been revealed that differences in the carbohydrate structure affect the effecter activity of antibodies such as antibody-dependent cellular cytotoxicity (ADCC) and their half-life in blood, inviting close attention from the viewpoint of improving the responses to antibody-based medicines [37,38,39]. 

NH4)6[AuCl4]3[Ag2Cl5] 0.11 Two of the AUCI4 ions stack alternately with the bridged Ag2Cls anion to form a double-stranded chain structure k... 

Fig. I (a). Strands of ZEN2O4 octahedra and SO4 tetrahedra forming wire like chains in [Zn(S04)(H20)2(2,2 -bpy)], I, from ref. 13. (b) Double stranded chains of [FeF3(S04)] " in H, from ref. 17. (c) Krdhnkite-type chain motif of [(V0)2(0H)2(S04)2] " in III, from ref. 15. (d) View of the [Zn(S04)2) " units along the i-axis showing the chains of comer sharing 4-ring built from Zn04 and SO4 tetrahedra in IV, from ref.l3. (e) Linerite- type chain of (CdCl2(S04)] " in V, redrawn from ref. 10.

The bases in a double-stranded chain are partially hidden from the light beam of a spectrophotometer by the other bases in close proximity, as though they were in the shadow of the other bases. When the strands unwind, these bases become exposed to the light and absorb it therefore,... 

Figure 6 The double-stranded chain of AgSCMeEt, in which the zigzag strands of alternating Ag and S atoms are intertwined but not bonded note the small outward displacements of opposing Ag atoms on different strands, consistent with a weak repulsive interaction. Reproduced with permission from Inorg. Chem., 22, 3785 (1983)...

Fig. 3 Double-stranded chain structure in the halogen-bonded co-crystal 5 between 2-mercapto-l-methylimidazole (1) and 1,4-diiodotetrafluorobenzene (2). Halogen-bonding distances S-. 1=3.314(1) A. 3.342(1) A. Colors are as follows black 70%—nitrogen black 50%—iodine black 30%—fluorine and hydrogen black 10%—sulfur and carbon. Dashed lines represent intermolecular halogen and hydrogen bondings. (View this art in color at www.dekker.com)...

Because a plasmid is circular, cleaving it this way produces a double-stranded chain with two ends (see I Figure 11.24). These are called sticky ends because each has one strand in which several bases are unpaired and ready to pair up with a complementary section if available. 

The study of optico-mechanical properties of one of ladder polyphenyIsesquioxanes in bulk has revealed the complex nature of the photoelasticity effect in the films of this polymer. Ladder polymers are characterized by high equilibrium rigidity of double stranded chains. ... 

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