Structure common architecture

Common architecture of [NiFe] hydrogenase crystal structures... 

Figure 6.9 Common architecture of [NiFe] hydrogenase crystal structures. [FeS] clusters, metal and xenon sites are shown as spheres. Included is also an averaged internal cavity map, calculated with an accessible probe radius of 0.1 nm, of D. gigas and Dm. baculatum hydrogenase.

Lipopolysaccharides form a class of macromolecules unique to Gramnegative bacteria. They are of great compositional and structural diversity, and yet, they are built up according to a common architectural principle. With few exceptions, lipopolysaccharides are biologically highly active substances. Lipopolysaccharides have been called endotoxins because of their toxic properties. Due to the antigenic properties which they confer to the surface of the bacterial cell, they are also termed O antigens. 

The purpose of this chapter is to provide an overview of ceramic materials used for photonic crystals, their synthesis, and macroscopic structures and architectures. Particularly close attention is given to the fabrication of silica colloidal crystals, since these forms are the most commonly studied. Initial efforts into devices are discussed, as are newer ceramic photonic crystal structures, including an overview of work in photonic crystal optical fibers. For completeness, nonoxide and organic photonic crystals also are included briefly. 

Similarities in structure commonly reflect similarities in biogenesis. Consideration of the architectural patterns and structural relationships of natural products enabled Collie, Robinson, Ruzicka and others to discern the biogenetic units from which certain phenolic compounds, alkaloids and terpenes were formed. A survey of the antibiotics indicates that one large collection of these substances can be derived mainly from amino acid residues, another mainly from acetate (or, on occasion, propionate) and a third from simple sugars. Some structures can be dissected into two or more different fragments that are derived from different types of biogenetic unit. 

The shape control of nanoparticles is a very important aspect in nanotechnology, due to the spectacular effects that structural anisotropy may have on many of the material s physical properties. Because of these size- and shape-dependent properties, much effort has been expended in controlling the morphology and assembly of nanoparticles [68-69]. The most common architecture of these nanocrystals is isotropic particles, ranging from spherical to highly faceted particles, such as cubic and octahedral. One-dimensional (1-D) anisotropic nanoparticles include uniform rods and wires, whereas two-dimensional (2-D) nanoparticles consists of nanodiscs, plates and other advanced shapes such as rod-based multipods and nanostars. 

Neuronal networks are nowadays predominantly applied in classification tasks. Here, three kind of networks are tested First the backpropagation network is used, due to the fact that it is the most robust and common network. The other two networks which are considered within this study have special adapted architectures for classification tasks. The Learning Vector Quantization (LVQ) Network consists of a neuronal structure that represents the LVQ learning strategy. The Fuzzy Adaptive Resonance Theory (Fuzzy-ART) network is a sophisticated network with a very complex structure but a high performance on classification tasks. Overviews on this extensive subject are given in [2] and [6]. 

Until Jenike developed the rationale for storage-vessel design, a common criterion was to measure the angle of repose, use this value as the hopper angle, and then fit the bin to whatever space was available. Too often, bins were designed from an architectural or structural-engineering viewpoint rather than from the role they were to play in a process. Economy of space is certainly one vahd criterion in bin design, but others must be considered equally as well. Table 21-14 compares the principal characteristics of mass-flow and funnel-flow bins. 

The following example provides information on designing of plastic structural products to take static loads. It is a structural problem common to a number of different structures to show how the different structural requirements will affect the choice architectural designers has to make. The design problem will be a roof section which may be used for anything from a work shed,... 

Similar residues in the cores of protein structures especially hydrophobic residues at the same positions, are responsible for common folds of homologous proteins. Certain sequence profiles of conserved residue successions have been identified which give rise to a common fold of protein domains. They are organized in the smart database (simple modular architecture research tool) http //smait.embl-heidelberg.de. 

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