Synergistic effect, analysis

A relatively new methodology caEed aroma dEution analysis (ada), which combines aroma dEution and gas chromatography-olfactometry to gain a better understanding of the relative importance of aroma compounds, was recently done for coffee. In a roasted Colombian coffee brew, 41 impact compounds were found with flavor dEution threshold factors (FD) greater than 25, and 26 compounds had FD factors of 100 or above. WhEe the technique permits assessment of the impact of individual compounds, it does not evaluate synergistic effects among compounds (13). 

W.C. Strahle J.C. Handley, Synergistic Effects and Deflagration Analysis In Composite Solid Propellant Combustion , Final Report, Contract N00014-75-C-0332... 

This form of approach is probably the only way to deal with multiple agents, for example where contaminants are added to the normal weathering factors of light, heat and water, and it can be extended to include synergistic effects. However, this quickly becomes very complicated and attempts at such analysis are not common. 

The morphology of the monoliths is closely related to their porous properties, and is also a direct consequence of the quality of the porogenic solvent as well as the percentage of crosslinking monomer and the ratio between the monomer and porogen phases. The presence of synergistic effects of these reaction conditions was verified using multivariate analysis [65]. 

Delavirdine mesylate is a member of the /7w(heteroaryl)piperazine (BHAP) class of nonnucleoside HIV-1 reverse transcriptase inhibitors (Adams et al., 1998 Romero et al., 1993 Romero, 1994). This class of compounds was discovered by Upjohn scientists from a computer-directed dissimilarity analysis of the Pharmacia Upjohn chemical library to select compounds for screening against HIV-1 RT. The result of the in vitro assay (Deibel et al., 1990) is an IC50 of 0.260 p,M, which is comparable to AZT. In accordance with the previous NNRTIs, delavirdine is a noncompetitive inhibitor of reverse transcriptase, and has a synergistic effect with nucleoside transcriptase and protease inhibitors (Chong et al., 1994). 

While an analysis of individual components in morama beans (above) can give a good lead to their possible beneficial and negative effects, it is the sum total, antagonistic or synergistic effects of the various component combinations which determine their overall effect on health. It is the high content of amino acids, and some fatty acids, complemented with minor... 

The principal impediment to effective process design and analysis is the limited understanding of synergistic effects due to ion, photon, and electron bombardment of solid surfaces during etching and deposition. Fundamental relationships must be established between the gas-phase chemistry the surface chemistry as modified by radiation and etch profiles, rates, selec-tivities, and film properties. 

In this equation, Wq and W[r are weighting factors that express the importance of the residuals obtained in the calorimetric and infrared determinations, respectively. The definition of these weightings is crucial for the results that are obtained, but is not at all straightforward. Recently, an approach to this problem based on an automated sensitivity analysis has been reported [17]. Besides tackling this problem of mathematically combining the evaluation of two different signals measured for the same experiment, we shall demonstrate in Section 8.3 that the application of both measurement techniques in parallel has synergistic effects for the clarification of the physical and chemical processes that are involved in the one experiment. 

Two-way analysis of variance (and higher classifications) leads to the presence of interactions. If, for example, an additive A is added to a lube oil stock to improve its resistance to oxidation and another additive, B, is added to inhibit corrosion by the stock under load or stress, it is entirely possible that the performance of the lube oil in a standard ball-and-socket wear test will be different from that expected if only one additive has present. In other words, the presence of one additive may adversely or helpfully affect the action of the other additive in modifying the properties of the lube oil. The same phenomenon is clearly evident in a composite rocket propellant where the catalyst effect on burning rate of the propellant drastically depends on the influence of fine oxidizer particles. These are termed antagonistic and synergistic effects, respectively. It is important to consider the presence of such interactions in any treatment of multiply classified data. To do this, the two-way analysis of variance table is set up as shown in Table 1.24. 

The use of phosphorus-based flame retardants in combination with other, better established, flame retardants is most effective in situations in which the combination proves synergistic. However, as yet our understanding of such synergistic effects is far from complete and more fundamental work is required in this area Work in which the gaseous and solid products of combustion, with and without the presence of flame retardants, are carefully analyzed. Such analyses can now be undertaken more readily than in the past, owing to the relatively recent development of techniques such as gas-phase FT-infrared spectroscopy and laser-pyrolysis time-of-flight mass spectrometry for the identification of volatiles, and solid-state NMR spectroscopy and x-ray photoelectron spectroscopy for the analysis of chars. 

Barten MJ, Streit F, Boeger M, et al. Synergistic effects of sirolimus with cyclosporine and tacrolimus analysis of immunosuppression on lymphocyte proliferation and activation in rat whole blood. Transplantation 2004 77(8) 1154-62. 

Tools should be developed to support the identification of mixture exposure situations that may cause unexpectedly high risks compared to the standard null models of CA and RA, for example, based on an analysis of food consumption and behavioral patterns, and the occurrence of common mixture combinations that cause synergistic effects. 

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