Factors influencing structure

Possible changes of main external governing factors influencing structure and regime of the river mouths of the Black Sea and the Sea of Azov region are the following ... 

Cassel, J. C., Kelche, C., Majchrzak, M., and Will, B. E., Factors influencing structure and function of intracerebral grafts in the mammalian brain a review, Restor. Neurol. Neurosci., 4, 65, 1992. 

Factors Influencing Structural and Chemical Properties of Catalysts Derived from Glassy Metals... 

Related topics Element structures (D2) Binary compounds factors influencing structure (D4)... 

A recent study by Beyer et al. (1979) has greatly illuminated the factors influencing structure in mucin oligosaccharides and it is discussed in detail below. 

The general list of factors influencing the uncertainty in the gross rock volume included the shape of structure, dip of flanks, position of bounding faults, position of internal faults, and depth of fluid contacts (in this case the OWC). In the above example, the owe is penetrated by two wells, and the dip of the structure can be determined from the measurements made in the wells which in turn will allow calibration of fhe 3D seismic. 

Once a reaction has been performed, we have to establish whether the reaction took the desired course, and whether we obtained the desired structure. For our knowledge of chemical reactions is stiU too cursory there are so many factors influencing the course of a chemical reaction that we are not always able to predict which products will be obtained, whether we also shall obtain side reactions, or whether the reaction will take a completely different course than expected. Thus we have to establish the structure of the reaction product (Figure 1-4). A similar problem arises when the degradation of a xenobiotic in the environment, or in a living organism, has to be established. 

Many of the spinel-type compounds mentioned above do not have the normal structure in which A are in tetrahedral sites (t) and B are in octahedral sites (o) instead they adopt the inverse spinel structure in which half the B cations occupy the tetrahedral sites whilst the other half of the B cations and all the A cations are distributed on the octahedral sites, i.e. (B)t[AB]o04. The occupancy of the octahedral sites may be random or ordered. Several factors influence whether a given spinel will adopt the normal or inverse structure, including (a) the relative sizes of A and B, (b) the Madelung constants for the normal and inverse structures, (c) ligand-field stabilization energies (p. 1131) of cations on tetrahedral and octahedral sites, and (d) polarization or covalency effects. ... 

Stcric and electronic factors influencing the structure of nickel(II) complexes. E. Uhlig, Coord. Chem. Rev., 1973,10, 227-264 (152). 

The Fluorite and Rutile Structures.—Compounds of the type MXS also have their choice of two ionic structures, but the factors influencing them... 

The 2 -chloro and 2 -bromo congeners of either 748 (FIAC) or 758 (FMAU) are more cytotoxic than FIAC and FMAU, suggesting that these chloro and bromo nucleosides, in contrast to the 2 -fluoro compounds, are comparatively better substrates for deoxycytidine kinase of human lymphocytes than the substrates for viral-specific thymidine kinase. The disposition of the 2 -fluoro group may also be important from the biological viewpoint. It should be noted that the structural difference between RNA and DNA is at the 2 -position. The ribo type of analog (738) of FIAC is 10 times less effective in suppression of HSV replication than is FIAC. Thus Fox, and Watanabe and coworkers concluded that the 2 - up fluorine disposition and the species of the substituent at C-5 are the two important factors influencing antiviral activity. Nevertheless, the mechanism of action of 2 -deoxy-2 -fluorocytidine (737) on certain herpes viruses, including HSV-1... 

One of the first applications of the HPLC method was the investigation of differences in toxin profiles between shellfish species from various localities ( ). It became apparent immediately that there were vast differences in these toxin profiles even among shellfish from the same beach. There were subtle differences between the various shellfish species, and butter clams had a completely different suite of toxins than the other clams and mussels. It was presumed that all of the shellfish fed on the same dinoflagellate population, so there must have been other factors influencing toxin profiles such as differences in toxin uptake, release, or metabolism. These presumptions were strengthened when toxin profiles in the littleneck clam (Prototheca Staminea) were examined. It was found that, in this species, none of the toxin peaks in the HPLC chromatogram had retention times that matched the normal PSP toxins. It was evident that some alteration in toxin structure had occurred that was unique in this particular shellfish species. 

The structure I might form a five-membered cyclic structure on Pd metal and then the structure would be adsorbed at the less bulky side of the molecule. On the other hand, structure II might not form such a cyclic structure because of the steric hindrance. The difference in the ease of formation of the cyclic complex between structure I and II might be an important factor why structure I is a major conformation in the reaction. It is assumed that the adsorpted state of reactants as structure I or II may be influenced by the reaction conditions such as the Pd metal size, resulting in the different enantioselectivity. 

Considerable studies have been done on the effects of the most important chemical and physical factors involved in the degradation of anthocyanins (temperature, light, pH, SO2, metal, sugar, and oxygen) in model systems and food extracts. In addition, anthocyanin concentrations, its chemical structures, and media compositions are fundamental factors influencing stability. 

The maximum absorption wavelengths in different solvents of many carotenoids can be found in the literature, and the % III/II values are also available for some carotenoids. It is common to find variations of 1 to 3 nm in for the same carotenoid in the same solvent cited in different publications. No identification based simply on the matching of recorded UV-Vis spectra with tabulated data can be done without considering the relationships of structures and the factors influencing light absorption. The principal factors that influence carotenoid UV-Vis absorption spectra are discussed below. 

Many factors influence how a policy is implemented and whether it achieves its objectives effectively. Experience in policy implementation in many areas indicate the importance of good organization. A number of organizational attributes, such as a sound structure, efficient procedures, well-trained personnel and adequate financial resources, are considered cmcial for effective policy execution (18, 19, 20, 21). 

This approach of using 2D and 3D monodisperse nanoparticles in catalytic reaction studies ushers in a new era that will permit the identification of the molecular and structural features of selectivity [4,9]. Metal particle size, nanoparticle surface-structure, oxide-metal interface sites, selective site blocking, and hydrogen pressure have been implicated as important factors influencing reaction selectivity. We believe additional molecular ingredients of selectivity will be uncovered by coupling the synthesis of monodisperse nanoparticles with simultaneous studies of catalytic reaction selectivity as a function of the structural properties of these model nanoparticle catalyst systems. 

Investigation of the differences in crystal packing between (431) and (426) from comparison of their respective X-ray structures, revealed that (431) was more tightly packed than (442), reflected in their respective melting points of 235 and 170 °C. It was postulated that the absence of in vivo activity for (431) may be explained by the resultant reduction in water solubility and dissolution rate compared with (426). The comparatively high calculated polar surface area of (431) (122.5A ) compared with (426) (89.3 A ) was also proposed as a factor influencing the marked difference in bioavailability between the two related compounds. Compound (426) (SLV-319) is currently being developed with Bristol-Myers Squibb for the potential treatment of obesity and other metabolic disorders. Phase I trials for obesity were started in April 2004. Earlier Phase I clinical trials for the treatment of schizophrenia and psychosis, which commenced in April 2002, appear to have been abandoned. 

Evans (1951) described land potential and measured it in terms of sustained yield of oats. The determining factors influencing yield were, as we have seen, soil type and climate, particularly rainfall. He then went on to calculate whether a particular farmer was achieving the optimal output, or whether he was under-achieving, or exploiting his land by over-production in the one case he was making less money than he could have and in the other case productivity would have quickly fallen as the soil lost both structure and nutrients. 

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