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International audience; A series of four micro- or mesoporous metal-organic frameworks [UiO-66(Zr), UiO-66(Zr)_NH2, MIL-100(Fe), MIL-127(Fe)] were synthesized in powder form and pelletized in the form of spheres by using a polyvinyl-based binder. The effect of pelletization on the adsorption of a series of gasses (N-2, CO, CO2, CH4, C2H6, C3H8, C3H6, C4H10) at 303 K was evidenced in the adsorption isotherms and the enthalpies of adsorption measured by using microcalorimetric analysis. As expected, up-takes of gas per gram of material were lower for the spheres than for the powder. However, taking into account the bulk density, this tendency was inverted, suggesting that the spherical materials are of distinct interest for gas-based applications. Nevertheless, other effects including partial pore restriction and active site "protection" may equally be evidenced for some pelletized materials, suggesting that the polyvinyl binder may play a more complex role.

There has been increasing awareness in the wider biological community of the role of clonal phenotypic heterogeneity in playing key roles in phenomena such as cellular bet-hedging and decision making, as in the case of the phage-λ lysis/lysogeny and B. Subtilis competence/vegetative pathways. Here, we report on the effect of stochasticity in growth rate, cellular memory/intermittency, and its relation to phenotypic heterogeneity. We first present a linear stochastic differential model with finite auto-correlation time, where a randomly fluctuating growth rate with a negative average is shown to result in exponential growth for sufficiently large fluctuations in growth rate. We then present a non-linear stochastic self-regulation model where the loss of coherent self-regulation and an increase in noise can induce a shift from bounded to unbounded growth. An important consequence of these models is that while the average change in phenotype may not differ for various parameter sets, the variance of the resulting distributions may considerably change. This demonstrates the necessity of understanding the influence of variance and heterogeneity within seemingly identical clonal populations, while providing a mechanism for varying functional consequences of such heterogeneity. Our results highlight the importance of a paradigm shift from a deterministic to a probabilistic view of clonality in understanding selection as an optimization problem on noise-driven processes, resulting in a wide range of biological implications, from robustness to environmental stress to the development of drug resistance.

The Be phenomenon, that is the ejection of matter from Be stars into a circumstellar disk, has been a long lasting mystery. In the last few years, the CoRoT (Convection, Rotation and planetary Transits) satellite brought clear evidence that Be outbursts are directly correlated with pulsations. We found that it may be the transport of angular momentum by waves or pulsation modes that brings the already rapid stellar rotation to its critical value at the surface, and allows the star to eject material. The recent discovery of stochastically excited gravito-inertial modes by CoRoT in a hot Be star strengthens this scenario. We present the CoRoT observations and modeling of several Be stars and describe the new picture of the Be phenomenon which arose from these results., Comment: 6 pages, proceedings of a conference held in Hakone, in press

A 200kW pilot scale DFB(dual fluidized bed) gasification system and FT(Fischer-Tropsch) system were investigated for BTL(Biomass to Liquid) process. The DFB gasifier is able to produce a high quality syngas for FT system since it inherently prevents mixing between product gas and combustion gas. In order to meet syngas purification requirement for FT system, high purity syngas cleaning technologies are necessary. In this study, tar, dust and parts of acid gases were removed in a wet scrubbing system and remaining acid gases and contaminants were cleaned by using a chilled-methanol (MeOH) absorption method at a high pressure condition. Syngas from the atmospheric gasifier was compressed more than 20bar and supplied for MeOH absorption tower which is able to remove COS and H2S under ppm level and also a respectable amount of CO2 in syngas. For FT system, iron-based catalyst was used in a fixed bed reactor. The reliability of the integrated BTL system was identified from long-term operation of 500 hours over several runs, and stable operating conditions were achieved. BTL diesel from FT reaction was compared with a commercial diesel fuel., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 872-874

Powder, agglomerates, and tablets of the microporous zirconium(IV) terephthalate metal-organic framework UiO-66 were evaluated for the selective adsorption and separation of xylene isomers in the liquid phase using n-heptane as the eluent. Pulse experiments, performed at 313 K in the presence of n-heptane, revealed the o-xylene preference of this material, which was further confirmed by binary and multicomponent breakthrough experiments in the presence of m- and p-xylene, resulting in selectivities at 313 K of 1.8 and 2.4 with regards to m-xylene and p-xylene, respectively. Additionally, because p-xylene is the less retained isomer, UiO-66 presents a selectivity pattern that is reverse of that of the xylenes' molecular dimension with respect to shape selectivity. The shaping of the material as tablets did not significantly change its selectivity toward the o-xylene isomer or toward p-xylene, which was the less retained isomer, despite a loss in capacity. Finally, the selectivity behavior of UiO-66 in the liquid n-heptane phase makes it a suitable material for o-xylene separation in the extract (heavy product) or p-xylene separation in the raffinate (light product) by simulated moving bed technology.

Fungal infection is prevalent in patients with diabetes mellitus. Thus, we investigated whether a pharmacokinetic interaction occurs between the anti-fungal agent itraconazole and the anti-glycaemic drug metformin, as both drugs are commonly administered together to diabetic patients and are metabolized via hepatic CYP3A subfamily in rats.Itraconazole (20 mg·kg(-1)) and metformin (100 mg·kg(-1)) were simultaneously administered i.v. and p.o. to rats. Concentrations (I) of each drug in the liver and intestine, maximum velocity (V(max)), Michaelis-Menten constant (K(m)) and intrinsic clearance (CL(int) ) for the disappearance of each drug, apparent inhibition constant (K(i) ) and [I]/K(i) ratios of each drug in the liver and intestine were determined. Also the metabolism of each drug in rat and human CYPs was measured in vitro.After simultaneous administration of both drugs, either i.v. or p.o., the total area under the plasma concentration-time curve from time zero to infinity (AUC)s of itraconazole and metformin were significantly greater than that of either drug administered alone. The metabolism of itraconazole and metformin was significantly inhibited by each other via CYP3A1 and 3A2 in rat and 3A4 in human microsomes.The significantly greater AUCs of itraconazole and metformin after i.v. administration of both drugs are probably due to competitive inhibition of the metabolism of each drug by each other via hepatic CYP3A1/2. Whereas after oral administration of both drugs, the significantly greater AUCs of each drug administered together than that of either drug alone is mainly due to competitive inhibition of intestinal metabolism of each drug by each other via intestinal CYP3A1/2.