Search results for "bdd"
showing 10 items of 103 documents
Environmental and ontogenetic constraints on developmental stability in the spatangoid sea urchin Echinocardium (Echinoidea).
2006
13 pages; International audience; Spatangoid irregular sea urchins are detritivorous benthic organisms particularly prone to variations of environment, and their mode of growth and plate morphology make them an appropriate model to assess the effects of environmental variations. Two populations of Echinocardium flavescens were sampled in two sites of the Norwegian coast characterized by contrasted environmental conditions. Different morphological descriptors (plate areas, interlandmarks distances, overall size, and shape of the posterior ambulacra) were used to appraise interindividual variations, and fluctuating asymmetry. The comparisons were carried out using classical fluctuating asymme…
Biogenic amine levels, reproduction and social dominance in the queenless ant Streblognathus peetersi
2006
Social harmony often relies on ritualized dominance interactions between society members, particularly in queenless ant societies, where colony members do not have developmentally predetermined castes but have to fight for their status in the reproductive and work hierarchy. In this behavioural plasticity, their social organisation resembles more that of vertebrates than that of the "classic" social insects. The present study investigates the neurochemistry of the queenless ant species, Streblognathus peetersi, to better understand the neural basis of the high behavioural plasticity observed in queenless ants. We report measurements of brain biogenic amines [octopamine, dopamine, serotonin]…
Electrochemical incineration of organic pollutants: effect of the nature of the pollutants and of the operative conditions
2010
Electrochemical incineration of organic pollutants: effect of the nature of the pollutants and of the temperature
2009
The electrochemical oxidation of some organic pollutants, including three carboxylic acids (oxalic, formic and maleic), at boron doped diamond (BDD) and DSA anodes, using galvanostatic alimentation, was investigated in order to study the effect of the temperature and of the nature of the pollutants on the process. In incineration electrolyses, the performances of the process in terms of carboxylic acid conversion and current efficiency dramatically depend on the adopted operative conditions. The abatement of the organic pollutant depends on the nature of the carboxylic acid. Quite interestingly, the opposite effect of the nature of the substrate on the performances of the process was observ…
Electrochemical abatement of chloroethanes in water: Reduction, oxidation and combined processes
2010
An electrochemical route, based on the anodic oxidation to carbon dioxide coupled with the cathodic reduction to de-halogenated hydrocarbons, was proposed for the treatment of waters contaminated by chloroethanes. The electrochemical abatement of two model compounds, namely 1,2-dichloroethane and 1,1,2,2-tetrachloroethane, was carried out by cathodic reduction at silver, anodic oxidation at boron doped diamond (BDD) and combined processes. The anodic oxidation gives rise to a high abatement of the concentration of both these compounds and of COD. The reduction of 1,1,2,2-tetrachloroethane proceeds also with high abatement but with the formation of some halogenated intermediates and final pr…
Electrochemical incineration of oxalic acid at boron doped diamond anodes: Role of operative parameters
2008
The electrochemical incineration of oxalic acid (OA) at boron doped diamond (BDD) anodes was investigated both theoretically and experimentally in order to find the influence of the operative parameters on the performances of the process. Polarization curves and chronoamperometric measurements indicate the probable occurrence of a direct electrochemical oxidation of OA at the surface of the BDD anode at low pH and of a hydroxyl radical-mediated reaction at high pH. When incineration electrolyses are performed at low pH with potentiostatic alimentation, a dramatic influence of the potential is observed. In amperostatic incineration, high CE are obtained when most part of the process was unde…
N-Glycosylation modification of proteins is an early marker of the enterocytic differentiation process of HT-29 cells
1990
International audience; The human colon cancer cell line HT-29 remains totally undifferentiated when glucose is present in the culture medium (HT-29 Glc+), while the same cells may undergo typical enterocytic differentiation after reaching confluence when grown in glucose-deprived medium (HT-29 Glc-). Recently, we demonstrated a deficiency in the overall N-glycan processing in confluent undifferentiated cells, whereas differentiated cells follow a classical pattern of N-glycosylation. The main changes in N-glycosylation observed in confluent undifferentiated cells may be summarised as follows: 1) the conversion of high mannose into complex glycopeptides is greatly decreased; 2) this decreas…
Study of the chlorfenvinphos pesticide removal under different anodic materials and different reactor configuration.
2021
The present manuscript focuses on the study of the electrochemical oxidation of the insecticide Chlorfenvinphos (CVP). The assays were carried out under galvanostatic conditions using boron-doped diamond (BDD) and low-cost tin dioxide doped with antimony (Sb-doped SnO2) as anodes. The influence of the operating variables, such as applied current density, presence or absence of a cation-exchange membrane and concentration of supporting electrolyte, was discussed. The results revealed that the higher applied current density the higher degradation and mineralization of the insecticide for both anodes. The presence of the membrane and the highest concentration of Na2SO4 studied (0.1 M) as a sup…
Electrochemical oxidation of organics in water: Role of operative parameters in the absence and in the presence of NaCl
2008
The electrochemical oxidation of organics in water was investigated theoretically and experimentally to determine the role of several operative parameters on the performances of the process in the presence and in the absence of sodium chloride. Theoretical considerations were used to design the experimental investigation and were confirmed by the results of the electrochemical oxidation of oxalic acid (OA) at boron doped diamond (BDD) or IrO(2)-Ta(2)O(5) (DSA-O(2)) anodes in a continuous batch recirculation reaction system equipped with a parallel plate undivided electrochemical cell. Polarization curves and chronoamperometric measurements indicated that, in the presence of chlorides, the a…
In vivo survival rate of rabbit morulae after vitrification in a medium without serum protein.
2000
The in vivo survival rate of rabbit morulae after vitrification in a mixture of dimethyl sulphoxide and ethylene glycol solution without protein supplement (WPS) was compared with two types of protein supplements: rabbit serum (RS) and bovine serum albumin (BSA). Significant dif- ferences were observed in the percentage of transferable embryos (undamaged embryos after devit- rification, 80.4 % versus 93.2 and 92.1 %, WPS, BSA and RS, respectively, P < 0.05) and live born rate (40.9 % versus 56.1 %, WPS and BSA, respectively, P < 0.05). Non-significant differences were, however, observed in the percentages of implanted embryos at 12 days post-ovulation induc- tion (56.7, 69.7 and 68.6 %), po…