Stage theory

Construct validation follows a three-stage process. The first stage, theory formulation, involves specifying relationships among constructs and their relation to external variables (e.g., etiological factors). Disorder x is created by process y. For example, a theory about the construct panic disorder could specify that it is caused by the catastrophic misinterpretation of benign bodily cues (Clark, 1986) or by a faulty suffocation monitor (Klein, 1993). Internal... 

A 1954 pnblication in the British Journal of Cancer by Peter Armitage and Richard Doll" (whom we mentioned a few pages back) entitled The age distribntion of cancer and a multi-stage theory of carcinogenesis can be seen as a seminal event in the evolution of onr understanding of the way in which cancers develop. Although there have been a nnmber of snccessfnl modifications and refinements of the Armitage-Doll model in the 50 years since its publication, it is still seen as broadly correct. 

Two-Stage Theory of Carcinogenesis. Historically, the induction of skin tumors was accomplished by repeated applications of a potent carcinogen (39). Berenblum (40), however, found that croton oil, when administered together with a carcinogen, led to more tumors than the carcinogen alone. Mottram (41) then reported that after multiple... 

Table I. The Effect of Various Compounds Implicated in the 2-Stage Theory of Carcinogenesis on CMP-NeuAc lactosylceramide Sialyltransferase Activity in Human Epithelial Carcinoma with (KB) Cells...

ARMITAGE, P. and DOLL, R. (1954). The age distribution of cancer and a multi-stage theory of carcinogenesis, Brit. J. Cancer 18, 1—12. 

Armitage P, Doll R. A two-stage theory of carcinogenesis in relation to the age distribution of human cancer. Br / Cancer. 1957 11(2) 161-169. 

Apart from the direct conformational changes in enzymes, which may occur at very high pressures, pressure affects enzymatic reaction rates in SCFs in two ways. First, the reaction rate constant changes with pressure according to transition stage theory and standard thermodynamics. Theoretically, one can predict the effect of pressure on reaction rate if the reaction mechanism, the activation volumes and the compressibility factors are known. Second, the reaction rates may change with the density of SCFs because physical parameters, such... 

Quite generally, however, all these experimental attempts to measure molecular parity violating effects depend on guidance from theory. In the initial stage, theory is needed to identify suitable molecular candidates with favourable properties for an experiment, while at a later stage, theory is needed to analyse and interpret the results of an experiment. In the fom th section, I will describe the methods currently available for the computation of molecular parity violating effects, but first I will outline briefly the way one has to go from the standard model of physics in order to arrive at the final working equations employed in these calculations. 

The mechanism of chemical carcinogenesis has been explained by either a two-stage theory or multi-stage theory which consists of initiation, promotion and progression stages [3]. In these stages, the initiation stage... 

The analysis of experimental results, in terms of HETP from the equilibrium-stage theory, is shown in Figure 9.9. One sees that there is little difference between the trends for the two, thus the separation on this adsorbent is not well-resolved. We will revisit this question of separation efficiency in the Exercises for this ehapter. 

Evaluation of motor skills acquisition is also an integral part of developing and implementing an effective simulation curriculum. Similar to Miller s assessment pyramid [21] (Figure 10.2) and Kopta s three-stage theory [22], Fitts and Posner s theory of motor skiUs learning [17]... 

Following measurement the data must be analysed to take into account the corrections needed for sample size effects (multiple scattering) and resolution broadening, in the case of cross-section measurements. At this stage theory is used. For example, resonance region data are analysed using a standard resonance formalism to obtain the parameters. 

Keywords Engineering Ethics Assessment Instruction Teaching qualifications Stage theory Teaching resources... 

Table 11.2 Five tenets of Piaget s stage theory...

In the prior section we made the case that there is an apparent apprehension among most engineering faculty to teach course content related to ethics. In addition, we noted that based on Kohlberg s stage theory of moral development, the expectation that students can understand the perspective of various individuals associated with a moral dilemma, may in fact be too aspirational. While Kohlberg s theory has been demonstrated as equally applicable across cultures, it is only reasonable to expect that students would have an increased difficulty in understanding a different perspective when the dilemma is set in a culture they are unfamiliar with. 

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