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531.
StrainsCandida lipolytica 4-1 andCandida lipolytica K were compared in their growth and dawaxing capacities during batch growth on model gas oil. The model gas oil was composed
of a mixture of even-numbered puren-alkanes (n-decane ton-dotriacontane) dissolved in dewaxed gas oil. The results show that both strains differ in their substrate specificity and
in the sequence of utilization of individualn-alkanes. Strain K, previously used for dewaxing of mineral oil, has its substrate specificity shifted toward the highern-alkanes. 相似文献
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533.
Human males provide facultative paternal investment to their offspring; that is, the male care is not necessary for the survival
of his offspring. It is expected that the degree of male investment (1) increases with growing paternity certainty, (2) increases
when investment increases the survival and later reproductive prospect of offspring and (3) declines when there are opportunities
to mate with multiple females. Using a large sample of adult offspring and their fathers (n = 245), we first investigated the role of two factors possibly involved in the assessment of paternity and subsequently regulating
the level of paternal investment: (a) father–child facial resemblance and (b) assortative mating for eye colour. Second, because
mating opportunities are inversely related to paternal investment, we also investigated how male facial attractiveness (a
cue of mate opportunities) correlates with paternal investment. In line with paternal investment theory, male investment positively
correlated with offspring facial resemblance. However, paternal investment were neither higher among blue-eyed couples, nor
there were preferences of blue-eyed men to marry with blue-eyed women. Moreover, father facial attractiveness was unrelated
to paternal investment. These results indicate that resemblance between offspring and their fathers still plays an important
role in paternal investment decision later in offspring’s life. 相似文献
534.
Tephroseris longifolia subsp. moravica is an endemic endangered taxon of European importance. Within the nine recently known populations it occurs in very specific
site conditions of ecotone habitats. In our contribution, we try to quantify its realized niche with regard to the measured
components of its biotic and abiotic environment. The main aim was to assess the importance of spatial environmental variation
on taxon occurrence and performance and to relate the obtained ecological information to data on taxon abundance and demography.
Possible reasons of taxon rarity are discussed, too. Comparison of plot pairs indicated that plots containing the taxon had
deeper soil and higher soil Na and Mg contents than plots without it. They also contained higher number of species, especially
forbs. Several soil parameters were positively correlated with taxon size and density while light parameters played minor
role. Negative correlations between cover of vascular plants, especially grasses and taxon size and density suggest its reduced
competitive ability. Vascular plant-based ecological indicator values were set for light (6), temperature (5), continentality
(4), moisture (5), soil reaction (7) and nutrients (5). The studied sites differed in topography, soil characteristics (pH,
soil Na, K, Ca, P and NH4) and cover of herb litter. Size of taxon populations was negatively related to their finite rate of increase which varied
between 1.25 and 2.04 and was most sensitive to demographic parameters related to growth. We conclude, that the studied taxon
is not strictly stenotopic as the ranges of several environmental variables were rather wide. We suppose, that the narrow
limits of recent taxon occurrence are consequences of its low competitive ability and demographic processes related to germination
and seedling establishment. The differing requirements of its ontogenetic stages (seedlings and generative individuals) may
define the final limits of its small-scale distribution. 相似文献
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538.
A Prokop 《Molecular biotherapy》1988,1(2):61-73
Engineering and physiologic aspects of growth and production processes associated with encapsulated cells, mostly of anchorage-independent type, are reviewed. They include membrane diffusion characterization, mechanical properties of microcapsules, process limiting phenomena, physiological state of cells, process modeling and product purity and concentration. Finally, application areas are spelled out with an outlook discussion. 相似文献
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