Intrinsic hypothesis

Intrinsic Hypothesis. The assumption of second order stationarity assumes that the variance exists (i.e., it is not equal to infinity). This assumption is still stronger than necessary. A random function is said to be intrinsic (i.e., satisfies the intrinsic hypothesis) when for every ... 

It is assumed that the intrinsic hypothesis holds within the limited neighborhood that is used in calculating the kriging estimates. That is, eight measurements will be used by the kriging estimator and within the limited neighborhood (with a radius of approximately 1000 feet) that these measurements occur it is assumed that there is no drift or systematic trend. 

The theoretical basis of the kriging method is the so-called intrinsic hypothesis. A random function Z(x) accomplishes this hypothesis if two assumptions are fulfilled ... 

Since equatorial attack is roughly antiperiplanar to two C-C bonds of the cyclic ketone, an extended hypothesis of antiperiplanar attack was proposed39. Since the incipient bond is intrinsically electron deficient, the attack of a nucleophile occurs anti to the best electron-donor bond, with the electron-donor order C—S > C —H > C —C > C—N > C—O. The transition state-stabilizing donor- acceptor interactions are assumed to be more important for the stereochemical outcome of nucleophilic addition reactions than the torsional and steric effects suggested by Felkin. 

Following the hypothesis of electron spin by Uhlenbeck and Goudsmit, P. A. M. Dirac (1928) developed a quantum mechanics based on the theory of relativity rather than on Newtonian mechanics and applied it to the electron. He found that the spin angular momentum and the spin magnetic moment of the electron are obtained automatically from the solution of his relativistic wave equation without any further postulates. Thus, spin angular momentum is an intrinsic property of an electron (and of other elementary particles as well) just as are the charge and rest mass. 

Intrinsic Permeability, Permeability-pH Profiles, Unstirred Water Layers (UWL), and the pH Partition Hypothesis... 

Intrinsic disorder might not be encoded by the sequence, but rather might be the result of the absence of suitable tertiary interactions. If this were the general cause of intrinsic disorder, any subset of ordered sequences and any subset of disordered sequences would likely be the same within the statistical uncertainty of the sampling. On the other hand, if intrinsic disorder were encoded by the amino acid sequence, any subset of disordered sequences would likely differ significantly from samples of ordered protein sequences. Thus, to test the hypothesis that disorder is encoded by the sequence, we collected examples of intrinsically ordered and intrinsically disordered proteins, then determined whether and how their sequences were distinguishable. 

Frisk et al. have compared the three basic methods on the same polyfpropylene terephthalate) (PPT) sample [56]. It appears that the assumption of a cylindrical Raman tensor may be too crude in some cases. Unless the hypothesis of a cylindrical tensor has been ascertained, the two other methods should be used. The "general" method is intrinsically the most accurate one but it... 

One of the original concepts governing oral absorption of organic molecules is the pH partition hypothesis . This hypothesis states that only the nonionized form of the drug is able to permeate the membranes of epithelial cells lining the GI tract [26], According to the classical pH-partition theory, permeability is expected to correlate not with the intrinsic partition coefficient but with the so-called distribution coefficient D of the solute [27], where D is defined as ... 

Such an arrangement is intrinsically associated with a downfield shift of the signals of the hydrogen-bearing carbon atoms. The physical meaning of this interaction, however, was not specified (146). On the basis of this reinterpretation steric crowding appears to cause downfield rather than upfield shifts (146), a hypothesis that is confirmed by the yg-SCS(Br) reductions cited in Tables 13 and 14 and by the appearance of a downfield-shifting 8M-SCS(X) (cf. Section III-E) (184). 

Klemmer et al. make the following conclusion Almost all studies reach the conclusion that enviromnent innovations are the result of a more complex than one-dimensional sample of effects, which is formed by both intrinsic motivations and also by state incentives, characterised by numerous feedbacks and is largely dependent on the overall social environment partly dictated by the design of the study, it is demonstrated using the example of selected sectors and/or groups of actors for the one part, and different environment policy problems for the other part, that there is no instrament to be favoured a priori or to be rejected generally and that only the interaction of individual motivations, political action and social enviromnent leads to environmental iimovations (multi-impulse hypothesis) (Klemmer ). 

The hypothesis of stereochemical control linked to catalyst chirality was recently confirmed by Ewen (410) who used a soluble chiral catalyst of known configuration. Ethylenebis(l-indenyl)titanium dichloride exists in two diaste-reoisomeric forms with (meso, 103) and C2 (104) symmetry, both active as catalysts in the presence of methylalumoxanes and trimethylaluminum. Polymerization was carried out with a mixture of the two isomers in a 44/56 ratio. The polymer consists of two fractions, their formation being ascribed to the two catalysts a pentane-soluble fraction, which is atactic and derives from the meso catalyst, and an insoluble crystalline fraction, obtained from the racemic catalyst, which is isotactic and contains a defect distribution analogous to that observed in conventional polypropylenes obtained with heterogeneous catalysts. The failure of the meso catalyst in controlling the polymer stereochemistry was attributed to its mirror symmetry in its turn, the racemic compound is able to exert an asymmetric induction on the growing chains due to its intrinsic chirality. 

For ease of solution, it is assumed that the spherical shape of the pellet is maintained throughout reaction and that the densities of the solid product and solid reactant are equal. Adopting the pseudo-steady state hypothesis implies that the intrinsic chemical reaction rate is very much greater than diffusional processes in the product layer and consequently the reaction is confined to a gradually receding interface between reactant core and product ash. Under these circumstances, the problem can be formulated in terms of pseudo-steady state diffusion through the product layer. The conservation equation for this zone will simply reflect that (in the pseudo-steady state) there will be no net change in diffusive flux so... 

The starting point is the hypothesis that the intrinsic viscosity is a direct function of the number of carbon atoms in the backbone chain. This addresses the first of the above considerations and is consistent with the homopolymer case and with the approach of Kruse and Padwa( ). The specific form of the functional dependence of intrinsic viscosity on the number of backbone carbon atoms is given by... 

Epilepsy is an example of excessive neural signaling in the central nervous system. Relative cellular and extracellular space (ECS) volume has been demonstrated to play an important role in the propensity for epileptic seizures. For example, reducing ECS volume by exposure to hypotonic medium produces hyperexcitability and enhanced epileptiform activity, whereas hyperosmolar medium reduces excitability. The hypothesis that AQP4-dependent water transport in astrocytes might modulate intrinsic brain excitability was tested by seizure susceptibility in response to the GABAa antagonist convulsant pentylenetetrazol... 

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