Molecular characteristics, optimization

Parameters (ii)-(vii) depend on the dielectric, mechanical and optical properties of the mesogens. To optimize a dis compromise between different molecular characteristics is often required and mixtures of liquid crystals are usually commercial displays. 

The two consecutive chemo-RT Phase I-II studies conducted showed that different molecular markers were associated with pathological response The finding supports the hypothesis that different drugs combined with concurrent radiation are effective on different tumor types. If this hypothesis is correct, selecting up-front which patient should be treated with one type of chemo-RT vs the other, based on the molecular characteristics of the tumor, may optimize pathological response rates, thus potentially reflecting on... 

Table 1 shows the aspect ratio values for the geometries of the stereoisomers of dendrimer 5 (G = 1) with Dj and Cj symmetries, obtained by semiempirical AMI optimizations. Other molecular characteristics, like their molar enthalpies of formation, entropies, and dipolar moments, which are relevant for a complete characterization of these isomers, are also given in Table 1. The aspect ratios of both isomers are very low, close to 1.3, indicating therefore spheroidal shapes in both cases. This fact is in complete agreement with the results previously described, suggesting that the first generations of both dendrimer series are close to the limit ones.

In order to verify the molecular and functional characteristics of the protein synthesized by the expression system, a number of molecular tools have been developed. These tools have been optimized over the years to allow efficient verification of the molecular characteristics of recombinant proteins. Some are also used for quality control procedures in the synthesis of recombinant proteins for pharmaceutical use. 

Different localized levels of molecular order can coexist in some pharmaceutical materials, giving rise to the occurrence of partially crystalline (and partially amorphous ) systems. In most cases, the properties of such materials (e.g., density) are intermediate to those of the 100% amorphous and 100% crystalline samples. By deliberately varying the level of crystallinity in such systems, their properties can be customized for a particular purpose. An example of this is with the tableting excipients microcrystalline cellulose and spray-dried lactose, which have had their compression characteristics optimized by manipulating their amorphous content. The properties of partially crystalline materials may be approximated in many instances by making physical mixtures of the totally amorphous and crystalline samples. This is known as the two-state model for partially crystalline systems.However, such experiments should be undertaken with caution as the mixed two-state material can sometimes have significantly different properties from the partially crystalline material that is manufactured directly (the real one-state system). ... 

TMAOase from different fish species have different molecular characteristics. TMAOase from lizardtish kidney has the molecular weight of 128 kDa with the optimal pH and temperature of 7°C and 50°C, respectively. The activation energy is... 

Thus, kinetic parameters of polymerization fast processes (kp, kd) and linear speed of flow V determine geometric sizes (R, L) and optimal configuration of reaction zone. New possibilities and methods of processes control allowing to regulate monomer conversion and molecular characteristics of resulting polymers, in particular by forced change (limitation) of reaction zone geometric parameters were revealed. 

The means by which molecular superposition is used to interpret this type of information varies almost as much as the data to be interpreted. For methods that describe data in terms of molecular characteristics, atoms, functional groups, or physical attributes, molecular superposition is the component common to all techniques. Techniques such as comparative molecular field analysis and 3D similarity are all founded on molecular superposition. Similarities may be used in compound design, compound optimization, and the identification of new compound classes. The resulting superposition sets are often generalized and the consistent spatial information referred to as a pharmacophore. The principal difficulty faced in molecular superposition is one of combinatorics. The number of ways even a pair of molecules may be superimposed is large, making the problem inherently complex. 

Although agreement with experiment is hardly complete, Flory suggests that practically it may be about optimal instead of seeking a theory which is accurate in detail as well as comprehensive in scope, it may be more fruitful to adopt a simpler treatment of reasonable generality at sacrifice of accuracy of representation of individual cases. Departures from such a scheme may then be interpreted. . . with reference to molecular characteristics of the particular components. ... 

To extract the conformational properties of the molecule that is being studied, the conformational ensemble that was sampled and optimized must be analyzed. The analysis may focus on global properties, attempting to characterize features such as overall flexibility or to identify common trends in the conformation set. Alternatively, it may be used to identify a smaller subset of characteristic low energy conformations, which may be used to direct future drug development efforts. It should be stressed that the different conformational analysis tools can be applied to any collection of molecular conformations. These... 

Energy calculations and geometry optimizations ignore the vibrations in molecular systems. In this way, these computations use an idealized view of nuclear position. In reality, the nuclei in molecules are constantly in motion. In equilibrium states, these vibrations are regular and predictable, and molecules can be identified by their characteristic spectra. 

Knowledge of the network parameters is important for understanding gelation processes, and relationships between the molecular structure and hydrogel synthesis conditions. The principles for the optimization of SAH characteristics for various application purposes can also be based on these parameters. 

The use of molecular biology methods, described in Section 5.3 seems to be especially worthwhile as it offers novel possibilities of optimization on process adjustment. Directed evolution leads to the formation of new biocatalysts with improved characteristics (selectivity, activity, stability, etc.). Incorporation ofnon-proteinogenic amino acids makes it possible to reach beyond the repertoire of building blocks used by nature. The prospect of bioconjugate preparation offers the possibility to form functional clusters of enzymes and to perform multiple synthetic steps in one pot. 

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