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61.
Chaima Chammakhi Alexandre Boscari Marie Pacoud Grgoire Aubert Haythem Mhadhbi Renaud Brouquisse 《International journal of molecular sciences》2022,23(21)
Drought is an environmental stress that strongly impacts plants. It affects all stages of growth and induces profound disturbances that influence all cellular functions. Legumes can establish a symbiosis with Rhizobium-type bacteria, whose function is to fix atmospheric nitrogen in organs called nodules and to meet plant nitrogen needs. Symbiotic nitrogen fixation (SNF) is particularly sensitive to drought. We raised the hypothesis that, in drought-stressed nodules, SNF inhibition is partly correlated to hypoxia resulting from nodule structure compaction and an increased O2 diffusion barrier, and that the nodule energy regeneration involves phytoglobin–nitric oxide (Pgb–NO) respiration. To test this hypothesis, we subjected faba bean (Vicia faba L.) plants nodulated with a Rhizobium laguerreae strain to either drought or osmotic stress. We monitored the N2-fixation activity, the energy state (ATP/ADP ratio), the expression of hypoxia marker genes (alcohol dehydrogenase and alanine aminotransferase), and the functioning of the Pgb–NO respiration in the nodules. The collected data confirmed our hypothesis and showed that (1) drought-stressed nodules were subject to more intense hypoxia than control nodules and (2) NO production increased and contributed via Pgb–NO respiration to the maintenance of the energy state of drought-stressed nodules. 相似文献
62.
The present longitudinal study traced the ideal self of 120 adolescents to the ideals that parents hold for themselves and for their children. Ideals were assessed using Q sorts for personality attributes and life goals. After permutation analysis was used to control for random similarity, moderate parent-child ideal-self similarity was evident. Three intermediate transmission steps accounted for this intergenerational similarity: (a) transfer of parents' ideal self to ideals for their children, (b) children's perception, and (c) acceptance of these parental ideals. The last 2 processes related to parenting practices, with parental warmth augmenting parent-child concordance and restrictiveness reducing it. Compared with boys' ideal self, that of girls was more similar to the ideals that parents hold for their children and for themselves. Analyses of patterns over time suggested a growth of ideal-self stability across adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Renaud P. Bouchard S. Proulx R. 《IEEE transactions on information technology in biomedicine》2002,6(3):235-243
Tracking behavior with a virtual spider and a neutral target is compared in fearful and nonfearful subjects. Head-tracking in virtual environments appears to be a scale-free behavior with long-range fractal-like patterns. Moreover, these fractal patterns change according to what the target affords the tracker and the level of behavioral avoidance manifested by the subjects. Results are interpreted in terms of ecological psychology and nonlinear dynamics, and implications for virtual reality (VR) psychology are outlined. 相似文献
64.
Determination of catecholamines by capillary zone electrophoresis with laser-induced fluorescence detection was performed on low-concentration samples, which were derivatized with naphthalene-2,3-dicarboxaldehyde to give highly fluorescent compounds. When the borate concentration in the derivatization medium was decreased from 130 to 13 mM, sensitivity for noradrenaline (NA) and dopamine (DA) was greatly enhanced while resolution between these two compounds decreased. A 50 mM borate concentration in derivatization medium was chosen since it provided maximal resolution between NA and DA, together with a high separation efficiency (3.1 million theoretical plates per meter for DA). The injection of 2.4 nL of a NA and DA solution derivatized at 10(-9) M produced peaks with signal-to-noise ratio of 8:1 and 3:1, respectively, corresponding to 1.8 amol of each catecholamine. The calibration curves were linear when NA and DA solutions were derivatized at concentrations ranging from 10(-6) to 10(-9) M. This method was used to determine NA in brain extracellular fluid: a peak corresponding to a basal level of 5 x 10(-9) M endogeneous NA was observed in microdialysates from the medial frontal cortex of the rat, and its nature was confirmed by both electrophoretic and pharmacological validations. 相似文献
65.
Pediatric anxiety disorders are common illnesses that, if left untreated, may induce academic, family, and interpersonal problems. Cognitive-behavioral techniques and other psychotherapeutic interventions may be adequate for the treatment of most anxiety disorders. For patients with severe symptoms or for whom psychotherapeutic approaches are not adequate, medications are indicated. Among the available medications, the SSRIs are currently the first choice; however, other medications, such as the benzodiazepines and the TCAs, may be used alone or sometimes in combination with the SSRIs. Caution with respect to medication interactions and side effects is indicated. In particular, long-term side effects in these medications have not been well studied. 相似文献
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67.
Separator materials suitable for use in industrial alkaline water electrolysers are surveyed, including both inorganic and organic materials. The properties which make asbestos diaphragms unsuitable for use above 100°C are also reviewed.In summary, potassium titanate and polyantimonic acid separator materials perform well in high-temperature alkali. Oxide-coated metallic diaphragms merit further attention. Polysulfone and polyphenylene sulfide polymers are promising, but will need definite improvement in their wettability. Asbestos stabilization by silicate electrolyte additions may be viable. 相似文献
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70.
Ludovic Apvrille Pierre de Saqui-Sannes Renaud Pacalet Axelle Apvrille 《电信纪事》2006,61(11-12):1347-1368
This paper introduces a new environment for developing distributed systems. It is based on theTurtle uml profile. Analysis and design phases, described in previous papers, have been extended with an additional deployment phase. In this new step,Turtle components are deployed over hardware execution nodes, and nodes are connected together throughout links,Turtle deployment diagrams are given a formal semantics inRt-lotos, therefore following the approach used forTurtle analysis and design diagrams. Moreover, the paper presents a Java code generator which outputs appropriate Java code forTurtle deployment diagrams. This code is automatically deployable on networks because it implements node communication using network protocols such asUdp orRmi. ttool, the turtle toolkit has been extended to support these new diagrams and code generators. The attack of protected data exchanged throughout securedHttp sessions serves as example. 相似文献