Intertwine

These fibers, intertwined in directions somewhat parallel to the surface of the skin, vary in size and shape and may be 0.01 mm in diameter. The length of these fibers vary but may be several centimeters long. The fibers are the ultimate in nonwoven stmcture that give leather its remarkable strength and flexibihty. 

Both of these areas, the mathematical and the statistical, are intimately intertwined when applied to any given situation. The methods of one are often combined with the other. And both in order to be successfully used must result in the numerical answer to a problem—that is, they constitute the means to an end. Increasingly the numerical answer is being obtained from the mathematics with the aid of computers. 

While these responsibilities seem straightforward, there are numerous responsibilities that are intertwined and discrete. Both parties need to understand their individual responsibilities especially regarding process hazards, environmental concerns, communication, and technology/knowledge transfer. 

Figure 3.1 Schematic diagram of the coiled-coil structure. Two a helices are intertwined and gradually coil around each other.

Figure S.21 The hemaggiutinin moiecuie is formed from three subunits. Each of these subunits Is anchored In the membrane of the influenza vims. The globular heads contain the receptor sites that bind to sialic acid residues on the surface of eukaryotic cells. A major part of the subunit interface is formed by the three long intertwining helices, one from each subunit. (Adapted from I. Wilson et al.. Nature 289 366-373, 1981.)...

The number of helical turns in these structures is larger than those found so far in two-sheet p helices. The pectate lyase p helix consists of seven complete turns and is 34 A long and 17-27 A in diameter (Figure 5.30) while the p-helix part of the bacteriophage P22 tailspike protein has 13 complete turns. Both these proteins have other stmctural elements in addition to the P-helix moiety. The complete tailspike protein contains three intertwined, identical subunits each with the three-sheet p helix and is about 200 A long and 60 A wide. Six of these trimers are attached to each phage at the base of the icosahedral capsid. 

The helices at the N-terminal regions of the two polypeptide chains are intertwined and make extensive contacts in the central part of the molecule to form a stable core. This core supports two "heads", each comprising the last three helices from one polypeptide chain. Alpha helix 3 in the middle of the subunit chain is quite long and forms the main link between the core and the head. 

Fibrous proteins can serve as structural materials for the same reason that other polymers do they are long-chain molecules. By cross-linking, interleaving and intertwining the proper combination of individual long-chain molecules, bulk properties are obtained that can serve many different functions. Fibrous proteins are usually divided in three different groups dependent on the secondary structure of the individual molecules coiled-coil a helices present in keratin and myosin, the triple helix in collagen, and P sheets in amyloid fibers and silks. 

The asymmetric unit contains one copy each of the subunits VPl, VP2, VP3, and VP4. VP4 is buried inside the shell and does not reach the surface. The arrangement of VPl, VP2, and VP3 on the surface of the capsid is shown in Figure 16.12a. These three different polypeptide chains build up the virus shell in a way that is analogous to that of the three different conformations A, C, and B of the same polypeptide chain in tomato bushy stunt virus. The viral coat assembles from 12 compact aggregates, or pen tamers, which contain five of each of the coat proteins. The contours of the outward-facing surfaces of the subunits give to each pentamer the shape of a molecular mountain the VPl subunits, which correspond to the A subunits in T = 3 plant viruses, cluster at the peak of the mountain VP2 and VP3 alternate around the foot and VP4 provides the foundation. The amino termini of the five VP3 subunits of the pentamer intertwine around the fivefold axis in the interior of the virion to form a p stmcture that stabilizes the pentamer and in addition interacts with VP4. 

In shock-compression science the scientific interest is not so much in the study of waves themselves but in the use of the waves as a means to probe solid materials. As inertial responses to the loading, the waves contain detailed information describing the mechanical, physical, and chemical properties and processes in the unusual states encountered. Physical and chemical changes may be probed further with optical, electrical, or magnetic measurements, but the behaviors are intimately intertwined with the mechanical aspects of the waves. 

It is indeed a distressing prospect to contemplate the complications introduced by chemical changes into an otherwise orderly physical description. The chemical complications are intimately intertwined with the mechanical and physical effects, which are already understood to be more complex than present theory indicates. As the questions addressed in solid state chemistry are quite different from those addressed in prior work, new approaches are required to develop a scientific understanding of the field. 

Shock-induced solid state chemistry represents the most complex fundamental problem ever encountered in shock-compression science. All the mechanical and physical complications of other work are present, yet the additional chemical complications are added. Indeed, all mechanical, physical, and chemical aspects of the problem are intimately intertwined. Chemical investigations promise to provide a description of shock compression that differs considerably from that to which we have become accustomed. Nevertheless, a full description of the process requires contributions from a number... 

The basic parameter characterizing supercoiled DNA is the linking number (L). This is the number of times the two strands are intertwined, and, provided both strands remain covalently intact, L cannot change. In a relaxed circular... 

H bonding also vitally influences the conformation and detailed structure of the polypeptide chains of protein molecules and the complementary intertwined polynucleotide chains which form the double helix in nucleic acids.Thus, proteins are built up from polypeptide chains of the type shown at the top of the next column. 

DNA is made up ot two intertwined strands. A sugar-phosphate chain makes up the backbone of each, and the two strands are joined by way of hydrogen bonds betwen parrs of nucleotide bases, adenine, thymine, guanine and cytosine. Adenine may only pair with thymine and guanine with cytosine. The molecule adopts a helical structure (actually, a double helical stnrcture or double helix ). 

The developmental histories of artificial life and cellular automata have been intertwined ever since von Neumann hrst showed how to construct a self-reproducing automaton ([voiiN66] see section 11.7). A brief historical overview of artificial life appears in chapter 11. 

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