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11.
Delia V?rg? Petru Lucian Cur?eu Lauren?iu Maricu?oiu Florin A. Sava Irina Macsinga Silvia M?gurean 《PloS one》2014,9(11)
This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members'' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models. 相似文献
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Protein domains are conspicuous structural units in globular proteins, and their identification has been a topic of intense biochemical interest dating back to the earlier crystal structures. Numerous disparate domain identification algorithms have been proposed, all involving some combination of visual intuition and/or structure-based decomposition. Instead, we present a rigorous thermodynamically based approach that redefines domains as cooperative chain segments. In greater detail, most small proteins fold with high cooperativity, meaning that the equilibrium population is dominated by completely folded and unfolded molecules, with a negligible subpopulation of partially folded intermediates. Here, domains are equated to chain segments that retain full cooperativity when excised from their parent structures. Implementing this approach computationally, the domains in a large representative set of proteins were identified; all exhibit consistency with experimental findings. Our reframed interpretation of a protein domain transforms an indeterminate structural phenomenon into a quantifiable molecular property, grounded in solution thermodynamics. 相似文献
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The use of plantations to manage extensive tracks of deforested lands in the tropics is a conservation strategy that has recently received considerable attention. Plantation trees can promote seed dispersal by attracting dispersers and creating favorable site conditions, leading to increased germination and establishment of indigenous trees. Subsequently, plantation trees can be harvested for profit or left to senesce, leaving a native tree community. We evaluated the effect of vine, grass, and shrub cutting (weeding) over a 3‐year period on regeneration of indigenous trees subsequent to the removal of plantation softwoods in Kibale National Park, Uganda. Counter to what would be expected if weeding released trees from competition, we found no difference in the total number of stems or in the stems greater than 10 cm diameter at breast height between control and weeded plots; there were more stems greater than 1 cm diameter at breast height in the control plots. For species found in both control and weeded plots, the maximum size of individuals did not differ. At the end of the study, 61 species were found in the control plots and 43 species were found in the weeded plots, and in both types of plots the three most abundant species were the same. The number of species and stems classified as early or middle successional species did not differ between weeded and control plots. The fact that weeding did not promote regeneration of indigenous trees after the removal of plantation trees illustrates the importance of evaluating and field‐testing potential management options. 相似文献
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Three anaerobic fluidized bed reactors at 37 degrees C were utilized to observe the effects of startup and operational procedures on biomass attachment. Using a meat-based synthetic waste and stepped-loading regime, the influences of synthetic polymer addition and maintenance of anaerobiosis during startup were investigated. Subsequently, increasing bed expansions were applied to assess shear effects. Synthetic polymer addition enhanced biomass retention but did not improve process performance. Maintenance of a reduced environment ameliorated fluctuating process parameters during start up and aided biomass retention and substrate removal. A bed expansion of 5% was detrimental to biomass attachment and COD removal but system stability was maintained at expansions between 10% and 30%. Startup was achieved in 56 days. Anaerobiosis appeared to enhance the initial evolution of a stable, well-adapted microbial population, whereas polymer addition interfered with this. Moderate bed expansions had negligible effects on attachment and performance. 相似文献
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Identification of protein kinase C and its potential substrate in Entamoeba histolytica 总被引:1,自引:0,他引:1
F De Meester D Mirelman T Stolarsky D S Lester 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,97(4):707-711
1. Protein kinase C (PKC) activity has been identified in various strains of the human parasite, Entamoeba histolytica. 2. An amoebic protein of mol. wt 78,000 was recognized by polyclonal antibodies raised against the 82,000 mol. wt rat brain protein kinase C. 3. A partially purified PKC preparation from E. histolytica phosphorylated histone I in the presence of calcium, phospholipids and diacylglycerol, and specifically bound tritiated phorbol ester at an apparent KD of 9 nM. 4. A relocalization of the amoebic PKC activity from the cytosol to the membrane fraction was observed when trophozoites were actively phagocytising bacteria. Under these conditions, a labelled phosphoprotein of mol. wt 68,000 was identified. 5. Similar to what was found during macrophage activation, a myristoylated mol. wt 68,000 protein was detected in amoebae grown in the absence of bacteria, but not in amoebae which were active in phagocytosis. 相似文献
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Morphological and seed protein analyses of 26 species of the generaLolium, Festuca andVulpia confirmed their close systematic affinities. Six inflorescence characters readily differentiatedFestuca fromLolium. Protein similarities betweenFestuca of sect.Bovinae and cross-pollinated species ofLolium, coupled with cytogenetic and crossability data, substantiate that they should be united into one genus.Vulpia had phenetic similarities with sect.Scariosae, Montanae andOvinae ofFestuca. Lolium, Festuca, andVulpia are most likely derived from a common ancestral form which was close toFestuca pratensis andLolium perenne. 相似文献