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Complete Independence (complete + independence)
Selected AbstractsEffects of maternal style on infant behavior in Japanese macaques (Macaca fuscata)DEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2002Massimo Bardi Abstract We assessed the association of maternal style and infant behavior of group-living Japanese macaques during the first year of infant development. We tested the hypothesis that different mothering styles were correlated with the behavioral repertoire of infants at three different developmental stages. We expected that infants of rejecting mothers would show a higher level of enterprise and that infants of protective mothers would be less interested in the external environment. We found evidence that maternal style affects infant behavior during the early developmental phase, but this influence becomes smaller as the infant grows older and approaches complete independence. Maternal protectiveness appears to have long-lasting effects on infant exploration as infants of protective mothers tended to be less attracted by the external environment. On the other hand, mater- nal rejection appears to have long-lasting effects on infant interaction with other group members as more rejected infants tended to initiate a significantly higher number of contacts with other juveniles and adults. These results suggest that both maternal rejection and maternal protectiveness play an important role in the independence of the offspring, in opposite directions. That is, rejection promotes independence whereas protectiveness delays it. © 2002 Wiley Periodicals, Inc. Dev Psychobiol 41: 364,372, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/dev.10065 [source] Comparison between the charring rate model and the conductive model of Eurocode 5FIRE AND MATERIALS, Issue 3 2009Paulo B. Cachim Abstract Eurocode 5, Part 1,2, presents several models for the calculation of fire resistance of timber structures. These models are based on the hypothesis that for temperatures above 300°C , wood is no longer able to sustain any stress, which makes the determination of the location of the 300°C isotherm decisive for the result provided by the models. In this paper, the charring rate model and the conductive model presented in Eurocode 5, Part 1,2 are compared regarding the determination of the location of the 300°C isotherm. The main wood parameters investigated are density, moisture content and anisotropy. The almost complete independence of the charring rate model from these parameters leads to some inconsistencies between the models. To reduce these inconsistencies some proposals to improve the conductive and the charring rate models are presented. Copyright © 2008 John Wiley & Sons, Ltd. [source] Spatio-temporal dynamics and local hotspots of initial recruitment in vertebrate-dispersed treesJOURNAL OF ECOLOGY, Issue 4 2008Arndt Hampe Summary 1Initial recruitment, or the arrival and establishment of propagules, is the most variable period in the life cycle of long-lived plants, and the extent to which studies of initial recruitment can be used to predict patterns of regeneration remains unresolved. 2We investigated the spatio-temporal dynamics of initial recruitment across five populations of three fleshy-fruited tree species from contrasting environments. Among-year variation in total seedfall, dispersed seedfall and seedling distributions was examined using analytical approaches that are new to the field and that explicitly incorporate space and allow comparisons among studies. 3Observed patterns ranged from remarkable across-year consistency in seedfall distributions and strong spatial coupling between seed and seedling stages to extensive variation and almost complete independence of stages. Spatial distributions of frugivore-mediated seedfall were markedly more consistent than those of the total seedfall in two of the five populations. Seedling distributions were generally more variable among years than seedfall distributions. 4All populations showed a positive relationship between the long-term mean density of recruitment at a given microsite and its year-to-year consistency. This relationship remained valid when considering only microsites away from fruiting tree canopies (i.e. those receiving actually dispersed seeds), and was virtually independent of their distance to the nearest fruiting tree. 5Synthesis. Our results point to the existence of some general rules behind the idiosyncratic recruitment dynamics of perennial plant populations, which should help with projecting spatial patterns of plant establishment in long-lived species. In particular, those microsites that combine a great intensity with a high year-to-year consistency of recruitment should represent potential regeneration ,hotspots' whose identification and characterization can be of great use for the management and conservation of naturally regenerating tree populations. [source] The molecular architecture of the arachidonate-regulated Ca2+ -selective ARC channel is a pentameric assembly of Orai1 and Orai3 subunitsTHE JOURNAL OF PHYSIOLOGY, Issue 17 2009Olivier Mignen The activation of Ca2+ entry is a critical component of agonist-induced cytosolic Ca2+ signals in non-excitable cells. Although a variety of different channels may be involved in such entry, the recent identification of the STIM and Orai proteins has focused attention on the channels in which these proteins play a key role. To date, two distinct highly Ca2+ -selective STIM1-regulated and Orai-based channels have been identified , the store-operated CRAC channels and the store-independent arachidonic acid activated ARC channels. In contrast to the CRAC channels, where the channel pore is composed of only Orai1 subunits, both Orai1 and Orai3 subunits are essential components of the ARC channel pore. Using an approach involving the co-expression of a dominant-negative Orai1 monomer along with different preassembled concatenated Orai1 constructs, we recently demonstrated that the functional CRAC channel pore is formed by a homotetrameric assembly of Orai1 subunits. Here, we use a similar approach to demonstrate that the functional ARC channel pore is a heteropentameric assembly of three Orai1 subunits and two Orai3 subunits. Expression of concatenated pentameric constructs with this stoichiometry results in the appearance of large currents that display all the key biophysical and pharmacological features of the endogenous ARC channels. They also replicate the essential regulatory characteristics of native ARC channels including specific activation by low concentrations of arachidonic acid, complete independence of store depletion, and an absolute requirement for the pool of STIM1 that constitutively resides in the plasma membrane. [source] | ||||||||||