Various Factors on Sensitization

VI. Influence of Various Factors on Sensitization A. Influence of Corticosteroids... 

We compare the effects of various factors on the 02 transfer rate in Figure 18. The 02 transfer rate is most sensitive to fetal arterial p0 (Table I), only slightly less sensitive to the sum of Qm + Qf, followed by fetal and maternal hemoglobin flow. Changes in DP, maternal arterial Po2, and Qm/Qr have little effect in the physiological range. 

Models can also be used for parameter sensitivity analysis. Due to the complexity of reaction networks and hydrodynamics, the effects of various factors on the reactor performance are complex. Model analysis provides a guiding tool for process development. The effects of PCa on the yield of acrylonitrile are shown in Fig. 30. As shown, when Pe is less than 0.05, the yield of acrylonitrile changes marginally with Pea, and the reactor can be considered well mixed. When Pea is greater than 10, the yield of acrylonitrile is almost the same as that in a plug-flow reactor. Model simulation also reveal the existence of a Pea-sensitive range... 

Various investigators have tried to obtain information concerning the reaction mechanism from kinetic studies. However, as is often the case in catalytic studies, the reproducibility of the kinetic measurements proved to be poor. A poor reproducibility can be caused by many factors, including sensitivity of the catalyst to traces of poisons in the reactants and dependence of the catalytic activity on storage conditions, activation procedures, and previous experimental use. Moreover, the activity of the catalyst may not be constant in time because of an induction period or of catalyst decay. Hence, it is often impossible to obtain a catalyst with a constant, reproducible activity and, therefore, kinetic data must be evaluated carefully. 

The IDL is dependent on various factors such as sensitivity of the detector for the analyte of interest and electronic and detector (instrumental) noise of various origins, e.g., thermal noise, shot noise, flicker (1 //) noise, environmenfal noise, efc. Several books and articles have been published on fhe different types of instrumental noise, e.g., Skoog and Leary s Principles of Instrumental Analysis . ... 

It is possible to identify various factors that confer on chemicals the ability to induce skin sensitization and allergic contact dermatitis. These include the capacity to gain access to the viable epidermis across the stratum corneum, to associate stably with host proteins, to provoke a certain degree of proinflammatory cytokine production by skin cells, and to be recognized by specific T lymphocytes. The effectiveness with which these requirements are met, and possibly other properties of the chemical that influence the vigor of induced immune responses, together with the extent of exposure, will dictate the degree to which sensitization is achieved. 

The selection of suitable single species and protocols is not a trivial task and may be dependent on various factors. Some of these include simplicity, low cost, or modest material and equipment demand. However, a higher sensitivity than other species to toxicants may be decisive in this choice in order to serve as warning systems. Table 1 shows the sensitivity in terms of effective concentration (EC50), which is the toxicity endpoint for the organisms (bacteria, crustaceans, algae, and fish) selected for the toxicity bioassays. These toxicity bioassays are usually classified according to the test species involved. 

Sensitivity of interfacial resistance to various factors. For perovskite mixed conductors on some ceria-based electrolytes, workers have reported virtually zero interfacial resistance such that the electrode overpotential is dominated entirely by dissociation of O2 and transport of intermediates to the electrode/ electrolyte interface. As we will see in section 6, this conclusion is not universally true of all materials additional impedance arcs have been observed for perovskites on YSZ and with ceria at lower temperatures or with certain electrolyte dopants. 

Dependence of sensitivity from various factors) (See our text) 9) Andreev Belyaev (I960), 302-11 (On influence on sensitivity of physical characteristics of explosives)... 

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