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Dynamic reactor operations will gain interest with the increase of intermittent electricity from renewable sources. Periodic operation of catalytic reactors can also be used for kinetic studies with better parameter estimation than steady-state operation. This methodology is exemplified for the case of acetylene hydrogenation over Pd/α-Al2O3 using small amplitude flow oscillations. It allows the evaluation of several elementary kinetic parameters from one set of dynamic data for a reaction mechanism based on a single catalytic site. The optimized transient model is able to reproduce the time-evolution of the reactant and product molar fractions at the outlet of a fixed bed operated with modulations of different amplitudes and frequencies. It further shows that the acetylene conversion is controlled by two steps, the hydrogen adsorption step and the hydrogenation of the surface vinyl intermediate into adsorbed ethylene

APOLT is a suitable technique of liver transplantation in patients with ALF and some types of MLD. Portal venous steal is a problem with this procedure that leads to graft dysfunction and failure. Modulation of the portal flow to the graft and native liver can help in preventing this problem. We discuss the pathophysiology of this complication, review available literature regarding its management, and describe our results using the technique of graded hemiportal banding to achieve adequate perfusion for the graft and native liver.

The present contribution is focused on the measurement of the analytical sensitivity attained in untargeted/targeted MS/MS experiments, performed using flow-modulator comprehensive 2D and 1D GC. The comprehensive 2D experiment was performed by diverting part of the high flow (circa 80%) to flush the accumulation loop (about 28 mL/min) to waste, to reduce the gas flow entering the ion source. 1D analyses were performed through: (i) unmodulated and (ii) single column applications. An equivalent temperature program was applied in the modulated and unmodulated analyses, while a faster one was employed in the single column one. In all application types, the (same) triple quadrupole instrument was operated in the full-scan and multiple reaction monitoring modes. A genuine sweet orange oil and the same sample spiked with 20 phytosanitary compounds were employed to reach the research objective. The results highlight the problems related to the flow modulation-MS combination. Specifically, it was found that sensitivity was on average three to four times higher in unmodulated and optimized single-column applications.

Aim To measure the impact of French national consensus guidelines on the clinical practices of primary care paediatricians and general practitioners. Design Non-randomized intervention study, with a first survey 1 year before the consensus development conference and a second survey 1 year after. Intervention Implementation of bronchiolitis management guidelines through the medical press and the Internet. Subjects Paediatricians and general practitioners treating infants 1 year of age and under consulting for a first-time episode of bronchiolitis. Results Ninety-three doctors and 510 infants were included during the first phase of the study and 96 doctors and 394 infants during the second phase. This study showed a slight increase in adherence to the guidelines for non-validated drugs (6.6% adherence before and 14.3% after), general advice (29.0% adherence before and 57.1% after) and flow modulation respiratory physical therapy (91.9% adherence before and 98.8% after). Increase in adherence to guidelines for other practices, that is, hospitalization, prescribing antibiotics and complementary examinations, was not statistically significant. Adherence to the guidelines on providing general advice increased the most between the two studies. Conclusion The guidelines helped practitioners evolve slightly in their approach to the treatment of bronchiolitis. Non-validated drugs remain frequently used. Additional resources for implementing the guidelines should be provided to improve primary care doctors’ practices.