Latin screening

Local sensitivity analysis is of limited value when the chemical system is non-linear. In this case global methods, which vary the parameters over the range of their possible values, are preferable. Two global uncertainty methods have been used in this work, a screening method, the so-called Morris One-At-A-Time (MOAT) analysis and a Monte Carlo analysis with Latin Hypercube Sampling (Saltelli et al., 2000 Zador et al., submitted, 20041). The analyses were performed by varying rate parameters, branching ratios and constrained concentrations within their uncertainty interval,... 

In this chapter we explore factorial-based experimental designs in more detail. We will show how these designs can be used in their full factorial form how factorial designs can be taken apart into blocks to minimize the effect of (or, if desired, to estimate the effect of) an additional factor and how only a portion of the full factorial design (a fractional replicate) can be used to screen many potentially useful factors in a very small number of experiments. Finally, we will illustrate the use of a Latin square design, a special type of fractionalized design. 

The fractional factorial designs, including the Latin squares, are generally used for screening possible experimental variables in order to find which are the most important for further study. Their use is subject to some fairly severe assumptions which should be known and taken into consideration when interpreting the data ... 

In a companion paper (Kleijnen et al., 2003), we changed the metamodel in (1) after the screening phase, as follows. For those controllable factors found to be important by sequential bifurcation, we augmented (1) with quadratic effects to form a predictive model for optimization. For those environmental or noise factors identified by sequential bifurcation as important, we created environmental scenarios through Latin hypercube sampling for robustness analysis. 

Bergman s original dissertation, published in Latin in 1775, is nearly identical in the order and in the content with the 1783 version. I am using the English translation of the latter version in 1785 which preserves more of the contemporary wording than Schufle s translation of the 1775 version. I have taken care, however, to compare the two versions to screen out the later additions Bergman, A Dissertation on Elective Attractions (London, 1785) reprinted with an introduction by A. M. Duncan (Cass, 1970). 

Due to the genetically diverse and polymorphous parasite, sensitivity of the prototype assay was assessed with various positive specimens from donors covering many regions of Latin Americas and southern US. 228 out of 228 specimens were detected as reactive or 100% sensitivity. Optimization to further improve the assay performance is in progress. The Abbott PRISM Chagas Assay is potentially a screening test to improve the safety of the blood supply by reducing the risk of T. cruzi transfusion. 

Much more interesting, and bewildering to the alchemist, is the electronic equipment in the room, showing only its screens and dials and not advertising immediately its purpose. Many of these procedures are forms of spectroscoj. The term is derived from the Latin word spectrum, or appearance, and the process of looking at the appearance but looking is now more sophisticated than visual inspection and appearance far removed from its everyday meaning. 

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