Search results for "Interactions"
showing 10 items of 1963 documents
Study of the benzene⋅N2 intermolecular potential-energy surface
2003
The intermolecular potential-energy surface pertaining to the interaction between benzene and N2 is investigated theoretically and experimentally. Accurate intermolecular interaction energies are evaluated for the benzene–N2 van der Waals complex using the coupled cluster singles and doubles including connected triples [CCSD(T)] method and the aug-cc-pVDZ basis set extended with a set of 3s3p2d1f1g midbond functions. After fitting the energies to an analytic function, the intermolecular Schrödinger equation is solved to yield energies, rotational constants, and Raman-scattering coefficients for the lowest intermolecular levels of several benzene–N2 isotopomers. Experimentally, intermolecula…
Intra-specific variability and biological relevance of P3N-PIPO protein length in potyviruses
2013
Background:Pipo was recently described as a new ORF encoded within the genome of the Potyviridae family members (PNAS 105:5897-5902, 2008). It is embedded within the P3 cistron and is translated in the +2 reading frame relative to the potyviral long ORF as the P3N-PIPO fusion protein. In this work, we first collected pipo nucleotide sequences available for different isolates of 48 Potyvirus species. Second, to determine the biological implications of variation in pipo length, we measured infectivity, viral accumulation, cell-to-cell and systemic movements for two Turnip mosaic virus (TuMV) variants with pipo alleles of different length in three different susceptible host species, and tested…
The poetry of the web : online ethnography of ordinary poets
2021
Through the observation of blogs, online reviews and accounts and profiles on Facebook and Twitter, this research is devoted to the online poetic activities of French-speaking poets (Belgium, France, Quebec, Switzerland). This research work is guided by a simple and general question: how do poets invent their own ways of making poetry with the web? I was interested in poetry being done empirically by focusing on observation, data collection and encounters with poets in an approach inspired by ethnographyGoing beyond the separation between amateurs and professionals, the analysis follows the interactions between these ordinary poets and the tools of the web. During learning, settling into th…
Anxiété et manipulation parasitaire chez un invertébré aquatique : approches évolutive et mécanistique
2020
Trophically transmitted parasites induce changes in their host’s phenotype. These changes are supposed to increase transmission probability to definitive hosts through the predation of intermediate hosts. This phenomenon is known as ‘parasite manipulation’ has been hypothesized to be an adaptive trait of parasites for a long time. As manipulation involves predator-prey interactions, it is therefore necessary to understand how antipredatory behaviours are modulated by exogenous (predation pressure) and endogenous (infection, emotional state) factors. We tried to go into this phenomenon in depth, in amphipods, by responding toseveral questions : (1) what is the extent of the multidimensionali…
Dynamiques de classe et efficacité scolaire
2003
The present research aims at describing the efficiency of teaching practices involved in dynamic "teaching-training" processes. Our main approach consisted in relating in-class-monitoring to the results of knowledge-acquisition by pupils so as to better explain through what means the pupils’ knowledge and competence are acquired. At a theoretical level this implies combining the "process-product" paradigm along with the "ecological" paradigm [ 1]. Results obtained indicate that bringing together the analysis of teaching practices with the evaluation of their impact "which are still limited to an exploratory stage" are a method well-worth pursuing. [ 1] See above the general introduction to …
Interspecific attraction between ground-nesting songbirds and ants: the role of nest-site selection
2021
Abstract Background Interspecific interactions within ecological networks can influence animal fitness and behaviour, including nest-site selection of birds and ants. Previous studies revealed that nesting birds and ants may benefit from cohabitation, with interspecific attraction through their nest-site choice, but mutual interactions have not yet been tested. We explored a previously undescribed ecological link between ground-nesting birds and ants raising their own broods (larvae and pupae) within the birds’ nests in a temperate primeval forest of lowland Europe. We tested whether the occurrence of ant broods within bird nests resulted from a mutual or one-sided interspecific attraction …
Modeling and 'smart' prototyping human-in-the-loop interactions for AmI environments
2021
[EN] Autonomous capabilities are required in AmI environments in order to adapt systems to new environmental conditions and situations. However, keeping the human in the loop and in control of such systems is still necessary because of the diversity of systems, domains, environments, context situations, and social and legal constraints, which makes full autonomy a utopia within the short or medium term. Human-system integration introduces an important number of challenges and problems that have to be solved. On the one hand, humans should interact with systems even in those situations where their attentional, cognitive, and physical resources are limited in order to perform the interaction.…
Spanish validation of the PICCOLO (Parenting Interactions With Children: Checklist of Observations Linked to Outcomes)
2019
Background/Objective: The aim of this study was to explore the psychometric properties of the Spanish version of the Parenting Interactions with Children: Checklist of Observations Linked to Outcomes (PICCOLO; Roggman et al., 2013a). This observational measure is composed of 29 items that assess the quality of four domains of parenting interactions that promote child development: affection, responsiveness, encouragement, and teaching. Methods: The sample included 203 mother-child dyads who had been video-recorded playing together. Fifty-six percent of the children were male, and 44% were female, aged from 10 to 47 months. Video-recorded observations were rated using PICCOLO items. Results: …
µ-Calpain conversion of antiapoptotic Bfl-1 (BCL2A1) into a prodeath factor reveals two distinct alpha-helices inducing mitochondria-mediated apoptos…
2011
Anti-apoptotic Bfl-1 and pro-apoptotic Bax, two members of the Bcl-2 family sharing a similar structural fold, are classically viewed as antagonist regulators of apoptosis. However, both proteins were reported to be death inducers following cleavage by the cysteine protease µ-calpain. Here we demonstrate that calpain-mediated cleavage of full-length Bfl-1 induces the release of C-terminal membrane active α-helices that are responsible for its conversion into a pro-apoptotic factor. A careful comparison of the different membrane-active regions present in the Bfl-1 truncated fragments with homologous domains of Bax show that helix α5, but not α6, of Bfl-1 induces cell death and cytochrome c r…
The role of biotic interactions in a prey-predator system : the case of predation and regulation of weed seeds by carabids.
2020
For the transition towards agricultural production systems that are less dependent on herbicides, the use of weed regulation by seed-eating carabids is of great interest. Weed seed predation by carabids is variable and occurs within a complex context of many biotic interactions. This complexity partly explains our current inability to predict levels of in-field weed regulation. In this thesis, I analysed variations in the levels of predation and biological regulation of weeds and determined how they respond to two classes of biotic interactions: 1) the availability of alternative prey; and, 2) intra- and inter-specific interactions between the carabids themselves. Field measurements carried…