Validity, of conclusions

A few comments are in order on the probable validity of conclusions based on this equivalent circuit to real cells. Quite simply stated, real cells that are properly designed will have the same properties as dummy cells of the same values of Rs, Ru, and Cdl. Important design features of a cell are (1) equal resistance between all points on the surface of the working electrode and the auxiliary electrode (2) low-impedance reference electrode and (3) low stray capacitance between electrodes, between leads, and to shields. Spherical symmetry is a good, but somewhat inconvenient, method of meeting the first requirement a parallel arrangement also works with planar electrodes. At the very... 

It should be emphasized that the validity of conclusion (iii) rests on our assumptions (a) that the distance of closest approach of X atoms of different vertex-sharing octahedra (x in Fig. 5.3(c)) may not be less than the distance X-X within an octahedron, and (b) that the octahedra are regular. Structures in which three octahedra share a common vertex but no edges or faces contravene (a) and/or (b). 

To assess the validity of conclusion 2 above, Brimblecomb (211) compared the trimethylammonium quaternary moiety with the 1-pyr-rolidino group in a series of compounds (Table 2.3). 

Statistical conclusion validity. Statistical conclusion validity refers to the validity of conclusions about whether the observed covariation between variables is due to change. In other words, it refers to the confidence with which one can say that there is a real difference in Y scores between X cases and X cases. 

The validity of conclusions based on induction is less clear than those based on deduction. Since no investigation can test every possible application of a theory or hypothesis, the conclusions made based upon that theory or hypothesis must be evaluated in a tentative or probabilistic sense. Conclusions based on a theory that has withstood a long period of empirical scrutiny with unmitigated success may be judged to be more valid than those based on a theory with fewer scientific credentials. Thus, the validity of a conclusion must be judged based on logic and the relative weight of the evidence that supports it. 

A.H. Robins began to market the contraceptive device in the United States in January 1971 despite questions among the fro s medical staff about the validity of conclusions drawn from the single effectiveness study (288). 

Two, apparently conflicting, requirements dominate the inference paradigm considerations in the real-time domains. One is the need for truth maintenance. With thousands of data changing rapidly, the validity of conclusions at all levels of inference are in question. The other requirement is for real-time performance, where real-time means fast enough to advise the human operator and/or control the robot or other process. 

Equations (10) and (11) require a precise knowledge of the relaxation time, which, typically, is obtained from the same trajectory. Nevertheless, these treatments provide reasonable estimates of statistical error that are essential for assessing the validity of conclusions from a simulation study. 

The method was applied for determination of the quality of the detection media on test pieces following the type testing of the European standard [4] in order to check the validity of the method. The other application was the determination of the visibility in dependance of the variations of the inspection parameters (application of the detection medium, magnetization, inclination, viewing conditions) in a range which may appear in the practical inspections. The results leads to conclusions on the visibility level which is a measure of the probability of recognition for the indication that means of the reliability of the method. 

It is possible that much of the inspection in future years will be focused on areas identified from databases which collate corrosion and damage history in similar ships. The validity of any conclusions derived from assessment programmes or databases can only be accepted if the quality of the original product is known. This would suggest that the NDE inspection programmes applied by some yards will have to be expanded. 

The two possible initiations for the free-radical reaction are step lb or the combination of steps la and 2a from Table 1. The role of the initiation step lb in the reaction scheme is an important consideration in minimising the concentration of atomic fluorine (27). As indicated in Table 1, this process is spontaneous at room temperature [AG25 = —24.4 kJ/mol (—5.84 kcal/mol) ] although the enthalpy is slightly positive. The validity of this step has not yet been conclusively estabUshed by spectroscopic methods which makes it an unsolved problem of prime importance. Furthermore, the fact that fluorine reacts at a significant rate with some hydrocarbons in the dark at temperatures below —78° C indicates that step lb is important and may have Httie or no activation energy at RT. At extremely low temperatures (ca 10 K) there is no reaction between gaseous fluorine and CH or 2 6... 

Using the test results, draw conclusions as to the validity of the theory... 

Although in vitro models clearly show that MDR transporters can protect tumor cells, their relevance in clinical oncology remains controver sial. As is the case for most potentially useful cancer biomarkers, no universally embraced guidelines for analytical or clinical validation of MDR transporters exist. Evidence linking ABCB1 Pgp/MDRl expression with poor clinical outcome is most conclusive for breast cancer, sarcoma, and certain types of leukemia. The relevance of the other MDR transporters in clinical MDR is still unclear. The prognostic implication of ABCCl/ MRPl remains controversial and very little is known clinically about ABCG2. 

It was of course not possible to introduce the deuterium atoms closer than three bonds away from the center of reaction , but the attenuation of the inductive effect with distance was not expected to affect the validity of the conclusions, especially considering the work of Streit-wieser and Klein (1964), who found that the isotope effect per deuterium in the solvolysis of benzhydryl chloride only decreased from 1 9% for deuterium in the ortho positions to l-5% for deuterium in the meta positions. 

CICADs are concise documents that provide summaries of the relevant scientific information concerning the potential effects of chemicals upon human health and/or the environment. They are usually based on selected national or regional evaluation documents or on existing EHCs. Before acceptance for publication as CICADs by IPCS, these documents undergo extensive peer review by internationally selected experts to ensure their completeness, accuracy in the way in which the original data are represented, and the validity of the conclusions drawn. 

The validity of pharmacoeconomic data is invariably diminished by two important factors a failure to account for all direct and indirect cost outcomes, and the difficulty of assigning costs to human experiences. In schizophrenia, validity is further reduced by the near-impossibility of conducting trials over several years, or even decades, so as to approach the reality of what is usually a lifelong illness. Given these observations, it would be imprudent to act on the minutiae of data generated in even the best-conducted trials, but it may well be appropriate to draw broad conclusions. 

Comparative Toxicokinetics. In humans, the targets for trichloroethylene toxicity are the liver, kidney, cardiovascular system, and nervous system. Experimental animal studies support this conclusion, although the susceptibilities of some targets, such as the liver, appear to differ between rats and mice. The fact that these two species could exhibit such different effects allows us to question which species is an appropriate model for humans. A similar situation occurred in the cancer studies, where results in rats and mice had different outcomes. The critical issue appears to be differences in metabolism of trichloroethylene across species (Andersen et al. 1980 Buben and O Flaherty 1985 Filser and Bolt 1979 Prout et al. 1985 Stott et al. 1982). Further studies relating the metabolism of humans to those of rats and mice are needed to confirm the basis for differences in species and sex susceptibility to trichloroethylene s toxic effects and in estimating human heath effects from animal data. Development and validation of PBPK models is one approach to interspecies comparisons of data. 

In this phase of the risk assessment, the validity and reliability of conclusions and advice to risk managers depend on the quality, reliability, and relevance of available exposure data. Therefore it is necessary to (1) critically review the facts from food composition tables and the reasons for differences reported by and within countries, (2) consider the way foods are categorized and thus made comparable (or not) in food consumption surveys, and (3) explore how to refine assessments as more information becomes available. ... 

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