Synergists definition

I was very surprised with the flavor of this beer. The black currant taste and aroma came throu very nicely. The combination of alcohol and caffeine is synergistic. Definitely not for tea-totalers. After about 2-3 weeks in the bottle, the tea flavor decreased dramatically. 

The edible parts of parsnips (Pastimea sativa L.), which have been consumed for centuries by humans without causing any obvious harm, were found to contain a chemical of insecticidal and strong synergistic nature (1). The insecticidal constituent, present at about 200 p.p.m., was isolated and identified as 5-allyl-l-methoxy-2, 3-methylenedioxybenzene or myristicin. Its toxicity to various insects [vinegar flies, houseflies, Mediterranean fruit flies, mosquito larvae, Mexican bean beetles, and pea aphids] was established and compared with pyrethrum and aldrin (Tables I and II). The knockdown effect, although definite, was not as great as that of pyrethrum. In tests... 

These equations do not provide complete definition of the reactions that may be of significance in particular solvent extraction systems. For example, HTTA can exist as a keto, an enol, and a keto-hydrate species. The metal combines with the enol form, which usually is the dominant one in organic solvents (e.g., K = [HTTA]en i/[HTTA]]jet = 6 in wet benzene). The kinetics of the keto -> enol reaction are not fast although it seems to be catalyzed by the presence of a reagent such as TBP or TOPO. Such reagents react with the enol form in drier solvents but cannot compete with water in wetter ones. HTTA TBP and TBP H2O species also are present in these synergistic systems. However, if extraction into only one solvent (e.g., benzene) is considered, these effects are constant and need not be considered in a simple analysis. 

It should be noted that synergism and potentiation may be defined in the reverse way in some texts, and the term insecticide synergists," as defined here, usually reflects potentiation. The definition used here is the same as that used in pharmacology. 

In retrospect, it is likely that for many substances the uncertainties could be considerably greater and probably toward the lower risk side, given the design and intent of the conservative calculation model On the other hand, lack of definitive information on potential synergistic or additive interactions could lead to a reason to take this more conservative approach. 

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. 

The definition of a poison, or toxicant, also involves a qualitative biological aspect because a compound, toxic to one species or genetic strain, may be relatively harmless to another. For example, carbon tetrachloride, a potent hepatotoxicant in many species, is relatively harmless to the chicken. Certain strains of rabbit can eat Belladonna with impunity while others cannot. Compounds may be toxic under some circumstances but not others or, perhaps, toxic in combination with another compound but nontoxic alone. The methylenedioxyphenyl insecticide synergists, such as piperonyl butoxide, are of low toxicity to both insects and mammals when administered alone but are, by virtue of their ability to inhibit xenobiotic-metabolizing enzymes, capable of causing dramatic increases in the toxicity of other compounds. 

The specific choice of treatments to be used in combination with hypothermia could be based on a variety of different approaches. First, there could be a direct synergistic effect between hypothermia and the other proposed treatment modality, presumably as a result of a complementary mode of action. For example, combining hypothermia with thrombolytic therapy might be an appropriate pairing in which the hypothermia prolongs the therapeutic window for subsequent definitive reperfusion. Similarly, hypothermia could be used just after thrombolysis, to prevent reperfusion induced injury and prolonging the viability of injured but not irreversibly damaged tissue. 

A binary solvent mixture exhibits synergistic effects on a physicochemical solute property P if for some mixtures this property P has a value higher or lower than either properties Pi and P2 corresponding to the neat solvents Si and S2 [379]. For example, the empirieally determined solvent polarity of binary mixtures of HBD and HBA solvents is often larger than the polarities of the two neat components. Clearly, the formation of hydrogen-bonded 1 1 complexes between HBD ad HBA solvent molecules leads to a new, more polar medium [124, 249, 377] (see Chapter 7 for a definition of the term solvent polarity). 

MRLs are, by definition (Chou et al. 1998), substance-specific and do not include effects attributable to interaction (whether additive, synergistic, or antagonistic) with other chemicals or environmental substances. Their relevance to the mission of ATSDR is to assist public health officials in the identification of chemicals/elements of potential health concern at hazardous waste sites. The ATSDR MRL is not intended to be used in the regulatory or site clean-up process, but is instead intended to serve as a basis of comparison with actual measured levels of environmental exposure. Further, the role of informed biomedical judgment is crucial in the application of any MRL, or the media-specific health guidance values (HGVs) derived from them, in any given exposure scenario (Risher and De Rosa 1997). MRLs for a particular substance are based upon the most sensitive effect/endpoint in that portion of the human population considered to be most susceptible to injury from exposure to that substance. Thus, the... 

In spile of the recognition that PBO and piperonyl cyclonene were powerful synergists with pyrethrins, they were originally described as new safe insecticides fWachs cr ah. 1950) and the authors claimed they had definite insecticidal properties in themselves ,... 

Synergistic integration (see Sect.. 5..5) is not handled in the PPM up to now. Hence, there is the question, where to place this part of the model. The corresponding specification should not to be included in the application domain model, because the definition of synergy refers to tool functionality. Also, synergy is not easy to be determined on a conceptual realization layer, since different specification formalisms are used in the tool realization case studies (i.e. column (b) on the one and columns (c) and (d) on the other hand). 

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