Joint effects

It should be emphasized that the value of tf resulting from use of (1.49) or (1.50) applies to a particular value of n,. Because of the joint effects of the energetic non-uniformity of the adsorbent surface and the interaction of adsorbate molecules in the adsorbed film itself, the heat of adsorption in general varies significantly with the amount adsorbed. It is therefore essential to repeat the calculation of (f for a succession of values of n, and thereby obtain the curve of against n,. 

Criteria stipulate conditions of exposure and may refer to sensitive population groups or to the joint effects of several pollutants. Air quality criteria are descriptive. They describe effects that can be expected to occur wherever the ambient air level of a pollutant reaches or exceeds a specific concentration for a particular time period. Criteria will change as new information becomes available. 

In some cases, the ventilation process in the room can be simplified and mechanisms of air and contaminant movement under the influence of each of the above factors can be described using simplified theoretical principles of fluid mechanics, empirical data, and observations from numerous research studies. In general, the ventilation process in a room is complex and different factors have a joint effect on airflow patterns and characteristics, in continued spaces and in industrial buildings particularly. 

Synergism, where the joint effect is greater than the sum of the effects of each dmg acting alone. 

HONG w K and wu x (2000) Dietary intake of isothiocyanates evidence of a joint effect with glutathione S-transferase polymorphisms in lung cancer risk . Cancer Epidemiol Biomarkers Prev, 9 1017-20. 

The kinetic equations describing the joint effects of activation and concentration polarization are very complex and we shall consider only the the case of a simple first-order reaction of the type (6.2) proceeding in the presence in the solntion of an excess of a foreign electrolyte. To simplify the appearance of these equations (which even in this case are very cnmbersome), in this section we use a more compact notation that contains two new kinetic parameters ... 

Alex Rosenberg We all recognise, I think, that correlation is not causation and is at most a symptom for either a causal relation, or for joint causes, or joint effects of a common cause, and the inference from correlation to causation is always an inductive one. 

If the odds ratio for pattern 1 (joint effect of genotype and drug) is significantly greater than the product of odds ratios for patterns 2 (independent effect of genotype) and pattern 3 (independent effect of drug), then there is evidence for statistical (multiplicative) interaction. This analysis can be carried out in the context of multiple regression analysis by the inclusion of an interaction term. 

We can see that due to joint effects of aridity and soil texture, the dust emission rates increase from east to west by as much as 5 orders. The maximum emission rate is 1.5 ton/ha/yr. The total dust emission amount of the Gobi desert is estimated as 25 x 106 tons per year and that in spring is 15 x 106 tons per year. The seasonal dust emission amounts in summer, autumn and winter are 1.4 x 106, 5.7 x 106 and 2.9 x 106 tons, correspondingly. 

An effect is simply a name for a transition between two states. We can define joint effects just as we define localized effects in Section 3.8.3. 

Effects can also be used when responsibilities of objects (or groups of objects, in the case of joint effects) are decided but their interfaces and interaction protocols are not yet known. You can then express actions in a factored form without choosing interfaces or protocols. 

Keywords. Organic pollutants, PAHs, PCBs, Aqueous-solid phase environment, QSAR, QSPR, multicomponent joint effect, Modeling... 

The study of joint toxic effects originated with the analysis of the effect of two compounds in binary mixtures. Plackett and Hewlett [344] identified four types of joint effects as follows ... 

According to this scheme, when Al = 0, components are simply additive if Al > 0, then they are more than additive, and if Al < 0, they are less than additive. Lewis and Perry [347] applied this scheme to analyze the joint effects of equi-toxic mixtures of three compounds on bluegills and found that Al value ranged from 0.30 to -1.23. Even though several Al values in that study deviated significantly from 0, they concluded that the compounds acted by simple addition, based on the average Al of 0.05. 

In this scheme, MTI = 1 implies simply additive, MTI = 0 implies independent action, MTI < 0 implies antagonism, MTI > 1 implies supra-addition, and 1 >MTI > 0 implies partial addition. Broderius and Kahl [349] used this scheme to analyze joint effects of several equitoxic 7-, 14-, and 21-component mixtures, and concluded simple additivity with MTI values ranging from 0.93 to 1.06. Hermens et al. [350] evaluated the joint effects of 14 miscellaneous compounds to Daphnia magna and concluded simple addition, with an average MTI of 0.95. 

In summary, the different joint effect models of multicomponent pollutant mixtures (i.e., the toxic unit, additive and mixture toxicity indices) were presented. Using such models to analyze the joint effect of a group of toxic and carcinogenic organic compounds such as polycyclic aromatic hydrocarbons will be presented and evaluated in Sect. 3.2. 

Genin VA, Medvedovskiy AG, Voronin VM. 1975. [Increased carcinogenic activity during joint effect of hydrobenzene (sic) and benzidine sulfate.] Gig Tr Prof Zabol 6 28-31. (Russian)... 

The word electrokinetic implies the joint effects of motion and electrical phenomena. We are interested in the electrokinetic phenomena that originate the motion of a liqnid within a capillary tube and the migration of charged species within the liquid that surrounds them. In the first case, the electrokinetic phenomenon is called electroosmosis whereas the motion of charged species within the solution where they are dissolved is called electrophoresis. This section provides a brief illns-tration of the basic principles of these electrokinetic phenomena, based on text books on physical chemistry [7-9] and specialized articles and books [10-12] to which a reader interested to stndy in deep the mentioned theoretical aspects should refer to. 

The joint effect of substituents and of temperature is clearly evident in imino-Reformatsky reactions of zinc dienolates197. At —78 °C, imines 194a-d react with crotonate derived zinc-dienolate 195, affording the products listed in Table 4. Imine substituents play a fundamental role in controlling the reaction regiochemistry. 

Multiple correlation coefficient an index which measures the joint effect of several variables on some response. 

The dihydroxyammonia has not been isolated, and it may or may not be an ephemeral intermediate product. W. R. Dunstan and T. 8. Dymond consider that the nitrogen formed in the reduction is the joint effect of hydroxylamine and dihydroxyammonia NH20H+NH(0H)2->N2+3H20. The relative proportions of the reduction products vary greatly within well-defined limits from a maximum down to almost zero. 

The amount of adsorbed hydrogen decreases in the presence of halide ions [395, 396]. This is due to a decrease in the M-H adsorption energy induced by ion-specific adsorption with partial charge transfer. The decrease in M-H bond strength results in an increase of overpotential. The effect is lower for Cl and higher for I -. However two joint effects are operative one due to electronic modifications, and the other one of an electrostatic nature related to a change in the local electric potential... 

The effect of the calcium/molybdenum combination was studied with the molybdenum line their joint effect was virtually identical to the sum of their separate effects (95% at the 1000 pg/ml level and 99% at the 4000 pg/ml level). These results agree with those of Maessen et al. [ 167]. A background correction is necessary in the determination of molybdenum when aluminium is present in the samples because of the enhancement of the background. 

To provide a comparative assessment on the effects caused by the severity of operational conditions in acid-catalyzed media, the joint effects of temperature, reaction time and catalyst have been interpreted in terms of the parameter CS (30). For isothermal conditions,... 

Zheng SL, Zheng W, Chang BL, Shu XO, Cai Q, Yu H, Dai Q, Xu J, Gao YT. Joint effect of estrogen receptor beta sequence variants and endogenous estrogen exposure on breast cancer risk in Chinese women. Cancer Res 2003 63 7624-7629. 

Many CYP3A substrates are also subject to efflux transport by P-gp at the intestinal mucosa (88-90). As discussed above, P-gp is inducible via activation of nuclear orphan receptors by the same inducers of CYP enzymes (91). Accordingly, for those drugs which are substrates of both CYP and P-gp, reduction in intestinal availability following treatment with known microsomal enzyme inducers could reflect the joint effects of increased mucosal metabolism and apical efflux. 

Description of joint effect Joint effects assessment... 

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