Conservatoire national des arts et métiers

About: Conservatoire national des arts et métiers is a education organization based out in Paris, France. It is known for research contribution in the topics: Population & Orthogonal frequency-division multiplexing. The organization has 3573 authors who have published 7127 publications receiving 141430 citations. The organization is also known as: CNAM & Conservatoire des arts et métiers.

5,10-methylenetetrahydrofolate reductase common mutations, folate status and plasma homocysteine in healthy French adults of the Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) cohort.

Abstract: The 677cytosine mutation identified in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been frequently associated with an elevated plasma homocysteine concentration. The aim of the present study was to determine the impact of this MTHFR common mutation on plasma and erythrocyte folate (RCF) and plasma total homocysteine (tHcy) concentrations in healthy French adults. A cohort of 291 subjects living in the Paris area and participating in the Supplementation en Vitamines et Mineraux Antioxydants (SU.VI.MAX) study were analysed to assess the impact of MTHFR polymorphism 677C-->T on folate status and plasma tHcy concentration. The frequency of the mutant homozygote for 677C-->T polymorphism (677TT genotype) in the present cohort was 16.8%. There were significant differences in plasma tHcy between 677CC, 677CT and 677TT genotype groups. The RCF concentrations were significantly different between each genotype, the lowest levels being associated with the 677TT genotype. When segregated by gender, no differences in tHcy between homozygous 677TT, heterozygous 677CT and wild-type 677CC genotype groups in women were observed. The fasting tHcy in women was unrelated to the 677C-->T mutation. However, tHcy was significantly increased in men with the homozygous 677TT genotype. We also analysed the possible implication of a second new MTHFR polymorphism (1298A-->C) in subjects with mild hyperhomocysteinaemia (4th quartile of homocysteinaemia; tHcy >11.1 micromol/l). The polymorphism 1298A-->C did not have a notable effect on tHcy or on the RCF levels. Our observations confirm a relatively high frequency of the 677TT genotype in the French population. Women with this genotype did not show the same increase in tHcy observed in men. In the present study dietary folate intake was not measured. Thus, the interaction of dietary folate with the MTHFR genotype in the French population needs further study.

A highly selective fluorescent molecular sensor for potassium based on a calix[4]bisazacrown bearing boron-dipyrromethene fluorophores

Abstract: The synthesis of a ditopic fluorescent sensor for cations associating a 1,3 alternate calix[4]bisazacrown-5 as an ionophore and substituted boron-dipyrromethene dyes as fluorophores is reported. Photophysical studies revealed that in medium and high polarity solvents an efficient charge transfer (CT) reaction occurs in the excited state leading to a dual emission and a strong quenching of fluorescence. This CT process is either totally suppressed by amino group protonation or hampered by cation complexation; in both cases, a strong fluorescence enhancement is observed. This “switching-on” of the emission is more pronounced when two cations are coordinated. The stability constants of complexes with sodium, potassium, caesium, calcium and barium cations were measured in acetonitrile and ethanol. The system shows a high sensitivity and selectivity for potassium over other metal ions. A test under physiological conditions was successfully achieved.

Temperature Swing Adsorption Process with Indirect Cooling and Heating

Abstract: Experimental results for a new TSA process including a rapid heat exchanger for indirect cooling and heating are presented. Experiments were performed for the removal and recovery of ethane from a nitrogen stream (simulating a VOC in air). In addition, a simplified one-dimensional nonisothermal nonequilibrium model of the process was developed. As temperature swing is the driving force in the process, specific efforts were made to evaluate the heat-transfer coefficient between the heating or cooling medium and the gas stream. From the combination of the experimental and numerical results, the influence of some parameters (e.g., regeneration temperature, initial feed composition) on the process efficiency, analyzed in terms of both recovered mass and energy consumption, was determined.

International Accounting Standardisation: Is Politics Back?

Abstract: In the absence of political legitimacy, international accounting standardisation is founded on procedural and substantial legitimacies, which have been challenged by the current financial crisis. This paper represents a critique of this built up legitimacy. It demonstrates in particular that whilst due process is admittedly a transparent procedure, it is one in which only those players with major financial and intellectual resources can participate. It also highlights the weakness of the theoretical foundation, in particular agency theory and the theory of efficient markets, on which the conceptual framework of the IASB rests. This critical study of the foundations of the legitimacy of the IASC/IASB enables us to understand the extent of recent political intervention in a field that had previously been abandoned. Whilst international accounting standards did not trigger the crisis, some observers have said that they accelerated and even amplified it, mainly as a result of their pro-cyclical nature. This e...

Finite element modelling of hybrid active–passive vibration damping of multilayer piezoelectric sandwich beams—part I: Formulation

Abstract: This work, in two parts, proposes, in this first part, an electromechanically coupled finite element model to handle active–passive damped multilayer sandwich beams, consisting of a viscoelastic core sandwiched between layered piezoelectric faces. The latter are modelled using the classical laminate theory, whereas the face/core/face system is modelled using classical three-layers sandwich theory, assuming Euler–Bernoulli thin faces and a Timoshenko relatively thick core. The frequency-dependence of the viscoelastic material is handled through the anelastic displacement fields (ADF) model. To make the control system feasible, a modal reduction is applied to the resulting ADF augmented system. Validation of the approach developed in this part is presented in Part 2 of the paper together with the hybrid damping performance analysis of a cantilever beam. Copyright © 2001 John Wiley & Sons, Ltd.