Theory-based research, influence

Concerning adherent cells there are few studies in the literature. Some of them deal with the influence of stirrer speed on microcarrier cultures. Most studies using defined forces are from medical research. These studies, as well as those with production cells, use different types of exposure systems based on the parallel plate theory. They investigate the influence of stress on cell morphology and viability which is most important for arteriosclerosis research. 

In a tiny fraction of cases, a quick formula can be used. For most cases, the analysis uses an options tree, with one leaf per possible outcome. However, this falls prey to the curse of dimensionality —the number of leaves on the tree grows exponentially in the number of risk and decision dimensions considered. Thus only a limited, simple set of situations can be optimized in this way because one has to severely limit the decisions and risks that are considered. Tools available to help automate and simplify options analysis, widely used in pharmaceutical project evaluation, include Excel addons such as R1SK [11] and more graphically based solutions such as DPL [12]. Both of these support the creation and evaluation of decision trees and of influence diagrams Figure 11.2 shows a simple example of each of these. A primer in applied decision theory is Clemen s book Making Hard Decisions, other sources may be found in the website of James Vornov, Director of Clinical Research at Guildford Pharmaceuticals, a recent convert to decision theory for options analysis [13]. 

Sometimes these heuristics are an extension of the theory and sometimes they are experience-based rules, with no apparent theoretical justification, but they simply work most of the time. One way of explaining human reasoning that has influenced the expert system research is that these heuristic rules of thumb are... 

The kinetic theory of collisions, which has been so effective in developing the kinetics of vapor-phase reactions, has substantially influenced research on the processes of liquid-phase oxidation and in describing these processes. It has been thought that the lack of laws on which to base liquid-state theory (in contrast to the well-developed kinetic theory of gases) would in principle severely limit the development of a quantitative theory of liquid-phase reactions. At present the characteristics of the liquid state are carefully considered in discussing the mechanism of intermolecular reactions, influence of the medium on reactivity of compounds, etc. 

Based on previous testing of the research subject, the design of the full factorial experiment 23 with one replication to determine experimental error has been chosen. To eliminate the influence of systematic error in doing the experiment, the sequence of doing design point-trials, in accord with theory of design of experiments, has been completely random. The outcomes are given in Table 2.107. 

In any system of instruction - particularly if it is computer-based -the critical issues are often the decisions that must be made prior to or in the early stages of development. In the following description of SPS s instruction, I focus on two types of decisions that influenced the shape of the instructional system those having to do with the mechanics of presenting information or recording responses and those having to do with the way that schema theory is incorporated. Whenever possible, both types of decisions were made on the basis of experimental investigations, either research done in my laboratory or published studies by other researchers. 

A second fundamentally important area of research, in which the influence of temperature was poorly understood, and in which an influence of hydrostatic pressure was unknown, was the physiological and biochemical action of narcotics and other drugs. Quantitative interpretations were attempted through various hypotheses, based for example on correlations between potency of action and solubility of the drug in olive oil, and distribution of the drug between water and olive oil at different temperatures.Other theories were based on partial agreement of quantitative effects with adsorption isotherms or on specific properties of the drug. - ... 

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