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951.
Chrea C Grandjean D Delplanque S Cayeux I Le Calvé B Aymard L Velazco MI Sander D Scherer KR 《Chemical senses》2009,34(1):49-62
Two studies were conducted to examine the nature of the verbal labels that describe emotional effects elicited by odors. In Study 1, a list of terms selected for their relevance to describe affective feelings induced by odors was assessed while participants were exposed to a set of odorant samples. The data were submitted to a series of exploratory factor analyses to 1) reduce the set of variables to a smaller set of summary scales and 2) get a preliminary sense of the differentiation of affective feelings elicited by odors. The goal of Study 2 was to replicate the findings of Study 1 with a larger sample of odorant samples and participants and to validate the preliminary model obtained in Study 1 by using confirmatory factor analysis. Overall, the findings point to a structure of affective responses to odors that differs from the classical taxonomies of emotion such as posited by discrete or bidimensional emotion theories. These findings suggest that the subjective affective experiences or feelings induced by odors are structured around a small group of dimensions that reflect the role of olfaction in well-being, social interaction, danger prevention, arousal or relaxation sensations, and conscious recollection of emotional memories. 相似文献
952.
953.
Jason Greenwald Mirella Nader Hervé Celia Christelle Gruffaz Valérie Geoffroy Jean-Marie Meyer Isabelle J. Schalk Franc Pattus 《Molecular microbiology》2009,72(5):1246-1259
The first step in the specific uptake of iron via siderophores in Gram-negative bacteria is the recognition and binding of a ferric siderophore by its cognate receptor. We investigated the molecular basis of this event through structural and biochemical approaches. FpvA, the pyoverdine–Fe transporter from Pseudomonas aeruginosa ATCC 15692 (PAO1 strain), is able to transport ferric–pyoverdines originating from other species, whereas most fluorescent pseudomonads are only able to use the one they produce among the more than 100 known different pyoverdines. We solved the structure of FpvA bound to non-cognate pyoverdines of high- or low-affinity and found a close correlation between receptor–ligand structure and the measured affinities. The structure of the first amino acid residues of the pyoverdine chain distinguished the high- and low-affinity binders while the C-terminal portion of the pyoverdines, often cyclic, does not appear to contribute extensively to the interaction between the siderophore and its transporter. The specificity of the ferric–pyoverdine binding site of FpvA is conferred by the structural elements common to all ferric–pyoverdines, i.e. the chromophore, iron, and its chelating groups. 相似文献
954.
Sebastien L'hoste Abderrahmen Chargui Radia Belfodil Christophe Duranton Isabelle Rubera Baharia Mograbi Chantal Poujeol Michel Tauc Philippe Poujeol 《Free radical biology & medicine》2009,46(8):1017-1031
The aim of this study was to characterize the role of CFTR during Cd2+-induced apoptosis. For this purpose primary cultures and cell lines originated from proximal tubules (PCT) of wild-type cftr+/+ and cftr?/? mice were used. In cftr+/+ cells, the application of Cd2+ (5 μM) stimulated within 8 min an ERK1/2-activated CFTR-like Cl? conductance sensitive to CFTRinh-172. Thereafter Cd2+ induced an apoptotic volume decrease (AVD) within 6 h followed by caspase-3 activation and apoptosis. The early increase in CFTR conductance was followed by the activation of volume-sensitive outwardly rectifying (VSOR) Cl? and TASK2 K+ conductances. By contrast, cftr?/? cells exposed to Cd2+ were unable to develop VSOR currents, caspase-3 activity, and AVD process and underwent necrosis. Moreover in cftr+/+ cells, Cd2+ enhanced reactive oxygen species (ROS) production and induced a 50% decrease in total glutathione content (major ROS scavenger in PCT). ROS generation and glutathione decrease depended on the presence of CFTR, since they did not occur in the presence of CFTRinh-172 or in cftr?/? cells. Additionally, Cd2+ exposure accelerates effluxes of fluorescent glutathione S-conjugate in cftr+/+ cells. Our data suggest that CFTR could modulate ROS levels to ensure apoptosis during Cd2+ exposure by modulating the intracellular content of glutathione. 相似文献
955.
956.
Nathalie Sibille Xavier Hanoulle Fanny Bonachera Dries Verdegem Isabelle Landrieu Jean-Michel Wieruszeski Guy Lippens 《Journal of biomolecular NMR》2009,43(4):219-227
Adding the 13C labelled 2-keto-isovalerate and 2-oxobutanoate precursors to a minimal medium composed of 12C labelled glucose instead of the commonly used (2D, 13C) glucose leads not only to the 13C labelling of (I, L, V) methyls but also to the selective 13C labelling of the backbone Cα and CO carbons of the Ile and Val residues. As a result, the backbone (1H, 15N) correlations of the Ile and Val residues and their next neighbours in the (i + 1) position can be selectively identified in HN(CA) and HN(CO) planes. The availability of a selective HSQC spectrum corresponding
to the sole amide resonances of the Ile and Val residues allows connecting them to their corresponding methyls by the intra-residue
NOE effect, and should therefore be applicable to larger systems. 相似文献
957.
The aim of this study was to clarify the importance of the soluble fraction on cell wall decomposition. Wheat plant was chosen as a model and was harvested at three stages of maturity: anthesis (A stage), 20 days after anthesis (B stage) and physiological maturity (PM stage). Wheat third internode (numbered down from the ear) were selected for this study. Internode age influenced the cumulative CO(2) kinetics with internodes from wheat stem harvested at anthesis mineralizing 62.1%+/-2.2 of added residue C whereas those harvested at the B and PM stages mineralized 58.8%+/-1.4 and 51.6%+/-1.7, respectively of the added C. Chemical analyses revealed that maturation of the selected internodes mainly altered residue quality by modifying the proportion of soluble to cell wall fractions rather than the quality of these fractions. The hexose to pentose ratios were good biomarkers of microbial sugars for both soluble and cell wall fractions, as were the uronic acids, which are not commonly determined in soil decomposition studies. This study clearly demonstrated that the contents of the internode soluble fraction did not affect the extent of cell wall C mineralization. Therefore, the soluble content of crop residues would not regulate the soil microbial populations able to mineralize cell wall C. However, this needs to be validated on a broader range of residue types with different nature of cell wall C or soluble compounds. 相似文献
958.
Laurent Mottron Michelle Dawson Isabelle Soulières 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1522):1385-1391
According to the enhanced perceptual functioning (EPF) model, autistic perception is characterized by: enhanced low-level operations; locally oriented processing as a default setting; greater activation of perceptual areas during a range of visuospatial, language, working memory or reasoning tasks; autonomy towards higher processes; and superior involvement in intelligence. EPF has been useful in accounting for autistic relative peaks of ability in the visual and auditory modalities. However, the role played by atypical perceptual mechanisms in the emergence and character of savant abilities remains underdeveloped. We now propose that enhanced detection of patterns, including similarity within and among patterns, is one of the mechanisms responsible for operations on human codes, a type of material with which savants show particular facility. This mechanism would favour an orientation towards material possessing the highest level of internal structure, through the implicit detection of within- and between-code isomorphisms. A second mechanism, related to but exceeding the existing concept of redintegration, involves completion, or filling-in, of missing information in memorized or perceived units or structures. In the context of autistics'' enhanced perception, the nature and extent of these two mechanisms, and their possible contribution to the creativity evident in savant performance, are explored. 相似文献
959.
This article first proposes a reduction strategy of the activated sludge process model with alternated aeration. Initiated with the standard activated sludge model (ASM1), the reduction is based on some biochemical considerations followed by linear approximations of nonlinear terms. Two submodels are then obtained, one for the aerobic phase and one for the anoxic phase, using four state variables related to the organic substrate concentration, the ammonium and nitrate‐nitrite nitrogen, and the oxygen concentration. Then, a two‐step robust estimation strategy is used to estimate both the unmeasured state variables and the unknown inflow ammonium nitrogen concentration. Parameter uncertainty is considered in the dynamics and input matrices of the system. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
960.
An outcome of the photochemistry during oxygenic photosynthesis is the rapid turn over of the D1 protein in the light compared
to the other proteins of the photosystem II (PS II) reaction center. D1 is a major factor of PS II instability and its replacement
a primary event of the PS II repair cycle. D1 also undergoes redox-dependent phosphorylation prior to its degradation. Although
it has been suggested that phosphorylation modulates D1 metabolism, reversible D1 phosphorylation was reported not to be essential
for PS II repair in Arabidopsis. Thus, the involvement of phosphorylation in D1 degradation is controversial. We show here that nitric oxide donors inhibit
in vivo phosphorylation of the D1 protein in Spirodela without inhibiting degradation of the protein. Thus, D1 phosphorylation is not tightly linked to D1 degradation in the intact
plant. 相似文献