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Objectives: Limited information about the pharmacokinetics of micafungin in the peritoneal cavity is available. The aim of this study was to explore the pharmacokinetics/pharmacodynamics of micafungin in plasma and peritoneal fluid in post-surgical critically ill patients with proven or suspected intra-abdominal fungal infection.Methods: Patients were administered 100 mg/day micafungin. Serial blood and peritoneal fluid samples were collected on day 1 and day 3 (steady-state) of treatment. Concentrations were determined by validated chromatography and were subject to a population pharmacokinetic analysis with Pmetrics(®). Monte Carlo simulations were performed for AUC0-24/MIC ratios in plasma. The PTA was calculated using AUC0-24/MIC cut-offs: 285 for Candida parapsilosis and 3000 for non-parapsilosis Candida spp.Results: Ten patients were included; six were male. The median (range) age, APACHE II score and Mannheim peritonitis index were 72 (43-85) years, 15 (11-36) and 26 (8-37), respectively. On day 1, median (SD) penetration of micafungin into the peritoneal cavity was 30% (30%-40%). A three-compartment model adequately described the data. The mean (SD) estimates for clearance and volume of distribution of the central compartment were 1.27 (0.75) L/h and 9.26 (1.11) L, respectively. In most patients, the PTA in plasma was ≥ 90% for MICs of 0.008-0.016 mg/L for Candida spp. and 0.125-0.25 mg/L for C. parapsilosis.Conclusions: After the first dose, micafungin at 100 mg/day achieves pharmacokinetic/pharmacodynamic targets in plasma for Candida spp. and C. parapsilosis MICs of 0.008-0.016 and 0.125-0.25 mg/L, respectively. [ABSTRACT FROM AUTHOR]

A full thermal experimental assessment of a novel dendritic cooling scheme for highpressure turbine vanes has been conducted and is presented in this paper, including a comparison to the current state-of-the-art cooling arrangement for these components. The dendritic cooling system consists of cooling holes with multiple interna! branches that enhance internal heat transfer and reduce the blowing ratio at hole exit. Three sets of measurements are presented, which describe, first, the local internaI heat transfer coefficient of these structures and, secondly, the cooling flow capacity requirements and overall cooling effectiveness of a highly engine-representative dendritic geometiy. Fullcoverage surface maps of overall cooling effectiveness were acquired for both dendritic and baseline vanes in the Annular Sector Heat Transfer Facility, where scaled nearengine conditions of Mach number, Reynolds number, inlet turbulence intensity, and coolant-to-mainstream pressure ratio (or momentum flux ratio) are achieved. Engine hardware was used, with laser-sintered metal counterparts for the novel cooling geometry (their detailed configuration, design, and manufacture are discussed). The dendritic system will be shown to offer improved overall cooling effectiveness at a reduced cooling mass flow rate due to a more uniform film cooling effectiveness, a decreased tendency for films to lift off in regions of low externa! cross flow, improved through-wall heat transfer and internal cooling efficiency, increased internal wetted surface area of the cooling holes, and the enhanced turbulence induced in them. [ABSTRACT FROM AUTHOR]

A new experimental technique for the accurate measurement of steady-state metal temperature surface distributions of modern heavily film-cooled turbine vanes has been developed and is described in this paper. The technique is analogous to the thermal paint test but has been designed for fundamental research. The experimental facility consists of an annular sector cascade of high pressure (HP) turbine vanes from a current production engine. Flow conditioning is achieved by using an annular sector of deswirl vanes downstream of the test section, being both connected by a three-dimensionally contoured duct. As a result, a transonic and periodic flow, highly representative of the engine aerodynamic field, is established: Inlet turbulence levels, mainstream Mach and Reynolds numbers, and coolant-to-mainstream total pressure ratio are matched. Since the fully three-dimensional nozzle guide vane (NGV) geometry is used, the correct radial pressure gradient and secondary flow development are simulated and the cooling flow redistribution is engine-realistic. To allow heat transfer measurements to be performed, a mainstream-to-coolant temperature difference (up to 33.5°C) is generated by using two steel-wire mesh heaters, operated in series. NGV surface metal temperatures are measured (between 20°C and 40°C) by wide-band thermochromic liquid crystals. These are calibrated in situ and on a per-pixel basis against vane surface thermocouples, in a heating process that spans the entire color play and during which the turbine vanes can be assumed to slowly follow a succession of isothermal states. Experimental surface distributions of overall cooling effectiveness are presented in this paper. By employing resin vanes of the same geometry and cooling configuration (to implement adiabatic wall thermal boundary conditions) and the transient liquid crystal technique, surface distributions of external heat transfer coefficient and film cooling effectiveness can be acquired. By combining these measurements with those from the metal vanes, the results can be scaled to engine conditions with a good level of accuracy. [ABSTRACT FROM AUTHOR]

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Abstract: In this work a predictive mathematical model has been developed to simulate the membrane-based solvent extraction of phenylglycine (PhgH) from alkaline solutions by trioctylmethylammonium chloride (TOMAC) (10%, v/v) in 1-decanol and the simultaneous membrane-based solvent stripping by chloride solutions using hollow fiber contactors. The model allows to predict the time-dependent concentration profiles of the three phases involved in the process, as a function of operating parameters (volumes, concentrations and volumetric flow rates), extraction mechanism parameters (distribution coefficients and equilibrium constants) and mass transfer coefficients. [Copyright &y& Elsevier]