Search results for "SELE"
showing 10 items of 4721 documents
Food selectivity and pickiness in adulthood: an age and gender-related behaviour?
2013
Food pickiness –or selectivity- is a behavior which may lead to a lack of variety and an unbalanced diet. While this trait has been studied in children, pickiness in adults has been more rarely explored and only recently in French elderly1. The first aim of the present work was to identify if pickiness varies according to age and gender in adults. The second aim was to examine the link between the selectivity score and self-reported degree of pickiness. Four hundred French adults from 25 to 75 years old answered an online survey. Respondents were asked to tick each food they dislike among a list of 71 food items. The selectivity score was the number of disliked food items1. Moreover, partic…
Modelling hydrolysis: Simultaneous versus sequential biodegradation of the hydrolysable fractions
2018
Hydrolysis is considered the limiting step during solid waste anaerobic digestion (including co-digestion of sludge and biosolids). Mechanisms of hydrolysis are mechanistically not well understood with detrimental impact on model predictive capability. The common approach to multiple substrates is to consider simultaneous degradation of the substrates. This may not have the capacity to separate the different kinetics. Sequential degradation of substrates is theoretically supported by microbial capacity and the composite nature of substrates (bioaccessibility concept). However, this has not been experimentally assessed. Sequential chemical fractionation has been successfully used to define i…
The noncovalent dimerization of a G-quadruplex/hemin DNAzyme improves its biocatalytic properties.
2020
While many protein enzymes exert their functions through multimerization, which improves both selectivity and activity, this has not yet been demonstrated for other naturally occurring catalysts. Here, we report a multimerization effect applied to catalytic DNAs (or DNAzymes) and demonstrate that the enzymatic efficiency of G-quadruplexes (GQs) in interaction with the hemin cofactor is remarkably enhanced by homodimerization. The resulting non-covalent dimeric GQ–DNAzyme system provides hemin with a structurally defined active site in which both the cofactor (hemin) and the oxidant (H2O2) are activated. This new biocatalytic system efficiently performs peroxidase- and peroxygenase-type biot…
Darwin et l'après-Darwin : une histoire de l'hypothèse de sélection dans la théorie de l'évolution
1992
Les historiens et les biologistes n'ont pas assez distingué la théorie et l'hypothèse de sélection naturelle. En tant que théorie générale de l'histoire de la vie, la doctrine de la sélection naturelle a sans aucun doute eu un immense retentissement dans la science et dans la culture de son temps. Mais l'hypothèse centrale de cette théorie, dans la forme très contraignante que lui avait donnée Darwin, s'est trouvée très vite exposée à des difficultés internes suffisamment redoutables pour entrer en crise à peine était-elle née. En liant rigidement l'hypothèse de sélection à l'hérédité, Darwin l'a exposée pour au moins cinquante ans à la menace permanente d'une réfutation. La sélection darwi…
Critics and Criticisms of the Modern Synthesis: the Viewpoint of a Philosopher
1990
International audience
Diversité et activités microbiennes dans la rhizosphère: des atouts majeurs en agroécologie
2012
National audience; Les rhizodépôts libérés par les plantes stimulent une microflore abondante et active dans la rhizosphère. La diversité des communautés microbiennes correspondantes est influencée par la nature des rhizodépôts (composition, molécules signal) qui diffère selon les génotypes végétaux. Le coût pour la plante correspondant à la libération de ces rhizodépôts est contrebalancé par le bénéfice issu des effets positifs de certaines populations microbiennes rhizosphériques sur la croissance et la santé de la plante-hôte. La connaissance des traits végétaux impliqués dans la sélection de ces populations bénéfiques, au sein des communautés microbiennes telluriques, représente un enje…
Genetic plasticity of atrazine-degrader: evidence for the deletion of atzABC genes in pseudomonas sp. adp in response to cyanuric acid selection pres…
2010
International audience; Several bacterial strains are known to metabolize s-triazines herbicides among which atrazine reported worldwidel to contaminate soil and water resources. The complete mineralization of atrazine to carbon dioxide and ammonium is catalyzed by 6 hydrolytic enzymes encoded by atzABCDEF genes located on the plasmid pADP1 in Pseudomonas ADP. The atzABC genes code for the upper pathway transforming atrazine to cyanuric acid, while the atzDEF genes code for the lower pathway transforming cyanuric acid to simple compounds. In order to study the genetic plasticity of the atrazine catabolic pathway, we performed an in vitro evolution study consisting in applying a continuous s…
Predicting pesticide biodegradation potential from microbial community composition: new tools for bioremediation
2022
Bioaugmentation is receiving increasing attention as a green technology to treat contaminatedareas by inoculating specific biodegrading microorganisms. However, our understanding of therole of microbial community composition and structure in the expression of contaminantdegradation potential is yet to improve. It could help making wise choice for microorganisms –community or specific strain – to be inoculated in contaminated soils with consideration to theirindigeneous microbiota.Here we tried to predict the microbial degradation of two herbicides, glyphosate andisoproturon by means of penalized regression and machine learning methods routinely used ingenomic selection. To this end, we cond…
Les phytoprotecteurs (« Safeners ») associés aux herbicides jouent-ils un rôle dans la sélection de résistances non liées à la cible ?
2016
Do herbicide-associated "Safeners" play a role in the selection for non-target-site resistances ? To ensure or improve crop selectivity, some herbicide molecules are applied in association with a “safener”. Safeners are compounds that, at the rate applied, enhance herbicide-degrading metabolic pathways supposedly specifically in crop plants. The metabolic pathways enhanced by safeners in crop plants are highly similar to those exacerbated in taxonomically closely related weed species that evolved non-target-site based resistance (NTSR) to herbicides. Herein, we show an enhancing effect of herbicide safeners on NTSR in a major noxious grass weed: rye-grass (Lolium sp.).
Pd-Cu catalysts supported on anion exchange resin for the simultaneous catalytic reduction of nitrate ions and reductive dehalogenation of organochlo…
2019
International audience; The present work proposes the simultaneous removal of these classes of pollutants by a catalytic hydrotreatment processes. For this purpose, bimetallic Pd-Cu catalysts (with mass ratio Pd:Cu of 4:1) supported on macroporous strong base anion resin were prepared by different methods. The catalysts were characterized (by XRD, SEMEDX, XPS, AAS and H-2 chemisorption) and tested in a continuous flow system. The selected catalyst preparation protocol consists in a two-step method, which implies the deposition of palladium by ion exchange and the subsequent deposition of copper by controlled reaction on the surface of the pre-reduced palladium. The effectiveness of the cata…