Sampling nested approach

The nested packed reactor (Fig. 5A0d) allows sample pretreatment prior to injection by means of solid oxidants, reductants, ion exchangers, immobilized enzymes, or suitable surface-active sorbents. The potential of this approach is largely unexploited, since so far such sample pretreatment has been used only to remove unwanted matrix, which is not retained on the column, for sample preconcentration, and for analyte conversion in connection with AAS and ICP (cf. Chapter 4.7). 

The blot overlay assay is a powerful method used to study protein-protein interactions and provides an especially useful means by which to identify potential protein ligands. In this approach, a radiolabeled protein probe is used to overlay protein samples immobilized on nitrocellulose. Because this assay allows detection of protein-protein interactions within the context of a complex mixture of proteins, this method is also useful to investigate the specificity of an interaction between two ligands. The blot overlay assay may also be used to define specific domains of a ligand involved in protein-protein interactions for example, proteolytic fragments of proteins or nested deletion fragments may be probed to determine which portion of a molecule contains the interactive site (Crawford ei al., 1992 Gilmore et al., 1992). In addition, the blot overlay procedure may be modified to probe cDNA libraries to identify bacterially expressed proteins that interact with labeled probes (Cicchetti et al., 1992 Blanar and Rutter, 1992). 

Nested case-control study A type of epidemiological research design which investigates the causal association between a risk factor and disease. Both case subjects (people who develop a disease) and control subjects (those who do not develop the disease) are selected from among a defined cohort in which the bio-sample or data of the individuals have been collected at the beginning of the study. Detailed exposure information, such as via the use of biomarkers, is analysed for cases and controls only, not for the entire cohort. The advantages of this design are that it is prospective and is less expensive than the full cohort approach. 

Like with continuous aleatory uncertainties, the influence of epistemic uncertainties is considered by Monte Carlo (MC) simulation (see chapter 2). The approach applied to account for both types of uncertainties is a double loop nested MC simulation Sets of values of the parameters subjected to epistemic uncertainty (epistemic variables) are sampled in the outer loop. For each of these sets, different sets of values for the continuous aleatory variables are sampled and contribute to the generation of different Dynamic Event Trees... 

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