Tolerance species differences

Formation of stable chelates with phytosiderophores occurs with Fe but also with Zn, Cu, Co, and Mn (Fig. 8) (39,207,208) and can mediate the extraction of considerable amounts of Zn, Mn, Cu, and even Cd in calcareous soils (204,209). There is increasing evidence that PS release in graminaceous plants is also stimulated in response to Zn deficiency (210-212), but possibly also under Mn and Cu deficiency (213). Similar to Fe deficiency, the tolerance of different graminaceous plant species to Zn deficiency was found to be related to the amount of released PS (211,212), but correlation within cultivars of the same species seems to be low (214). It is, however, still a matter of debate as to what extent PS release is a specific response to deficiencies of the various inicronutrients. Cries et al. (213) reported that exudation of PS in Fe-deficient barley was about 15-30 times greater than PS release in response to Zn, Mn, and Cu deficiency. In contrast, PS exudation in Zn-deficient bread wheat was in a similar range as PS... 

The temperature effect on the decay rate of H202 in unfiltered Sharpes Bay water was determined by allowing samples to equilibrate at several temperatures (Figure 6). H202 was spiked in all samples, and the decay was followed for several half-lives. With lower water temperatures the decay rate constants were lower. As yet this has not been verified over a season. As water temperatures change the relationship may differ for cold-tolerant species. H202 decay studies have also been conducted in waters from the... 

The kinetics of the excretion of various silver compounds are well characterized in animals and limited human data exist for inhalation and oral exposure. Further study into (1) the underlying basis for observed species differences (2) quantitation of the elimination of dermally absorbed silver compounds and (3) the basis for observed interpersonal differences in tolerance would aid in identification of human subpopulations with varying susceptibilities to the toxic effects of silver. 

Taylor, L.N., Wood, C.M. and McDonald, D.G. (2003) An evaluation of sodium loss and gill metal binding properties in rainbow trout and yellow perch to explain species differences in copper tolerance, Environmental Toxicology and Chemistry 22 (9), 2159-2166. 

Greenway, H. and C.B. Osmond (1972). Salt responses of enzymes from species differing in salt tolerance. Plant Physiol. 49 256-259. 

Species differ enormously in the range of body temperatures they can tolerate, as well as in the absolute temperatures at which they can live. 

Different copper compounds mainly replaced TBT as the active component in anti-fouling products (Dahl and Blanck 1996 Yebra et al. 2004). However, several algal species showed tolerance to copper and to achieve protection against these tolerant species, a number of so-called booster biocides, e.g. zinc pyrithione, irgarol... 

Heating of the N,N-diarylamines with palladium(II) acetate in acetic acid at reflux results in smooth oxidative cyclization to the corresponding carbazole derivatives. A variety of substituents are tolerated in different positions. Thus, this procedure has found many applications in organic syntheses [30,55]. However, the drawback is that stoichiometric amounts of palladium(II) are required, as one equivalent of palla-dium(O) is formed in the final reductive elimination step. In the Wacker process, regeneration of the catalytically active palladium(II) species is achieved by oxidation of palladium(O) to palladium(II) with a copper(II) salt [57]. We were the first to demonstrate that oxidative regeneration of the catalytically active palladium(II)... 

Walters M. B. and Reich P. B. (1999) Low-light carbon balance and shade tolerance in the seedlings of woody plants do winter deciduous and broad-leaved evergreen species differ New Phytol. 143, 143-154. 

Tropinone is stereospecifically reduced to yield both tropine (3a-hydroxytropine), which led to the formation of tropane alkaloids, and pseudotropine (3p-hydroxytropine), the precursor of calystegines. These stereospecific reductions are catalyzed by two different tropinone reductases, tropinone reductase I and II (TRI and TRII). Both enzymes have been isolated from many Solanaceous species. Thus, TR I and TR II were isolated from D. innoxia roots and the crude extract favoured the production of pseudotropine over tropine [151]. Also, from transformed root cultures of D. stramonium two different tropinone reductases were obtained. In this species, TRI showed about 5-fold larger activity than TRII, and TRI displayed a pronounced pH-dependency, while TRII was more tolerant to different pH values [152]. Moreover, two tropinone reductases were also isolated from H. niger root cultures. TRI-reduction was reversible, whereas TRII-reduction was essentially irreversible [153]. In subsequent studies it was found that the accumulation of both TRs was the highest in the lateral roots of H. niger throughout development, with different cell-specific patterns [154]. 

From the number of different species of fauna (diversity) and an appreciation of their relative sensitivity to pollutants, much can be learned about the condition of fresh or marine waters and sediments [57, 58]. Field experiments to determine the presence or absence of pollution-sensitive species of plants relative to the abundance of tolerant species can also be used [59]. They can also help to determine the bioavailability and acute toxicity of pollutants in bottom sediments. 

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