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We present a cost-effective metabarcoding approach, aMPlex Torrent, which relies on an improved multiplex PCR adapted to highly degraded DNA, combining barcoding and next-generation sequencing to simultaneously analyse many heterogeneous samples. We demonstrate the strength of these improvements by generating a phylochronology through the genotyping of ancient rodent remains from a Moroccan cave whose stratigraphy covers the last 120 000 years. Rodents are important for epidemiology, agronomy and ecological investigations and can act as bioindicators for human- and/or climate-induced environmental changes. Efficient and reliable genotyping of ancient rodent remains has the potential to deliver valuable phylogenetic and paleoecological information. The analysis of multiple ancient skeletal remains of very small size with poor DNA preservation, however, requires a sensitive high-throughput method to generate sufficient data. We show this approach to be particularly adapted at accessing this otherwise difficult taxonomic and genetic resource. As a highly scalable, lower cost and less labour-intensive alternative to targeted sequence capture approaches, we propose the aMPlex Torrent strategy to be a useful tool for the genetic analysis of multiple degraded samples in studies involving ecology, archaeology, conservation and evolutionary biology. [ABSTRACT FROM AUTHOR]

A comprehensive experimental investigation of helicopter blunt fuselage drag reduction using active flow control is being carried out within the Clean Sky project. The objective is to demonstrate the capability of several active technologies to decrease fuselage drag by alleviating the flow separation occurring in the backdoor area of some helicopters (with pronounced ramp for backdoor loading). The work is performed on a simplified blunt fuselage at model scale. Several active flow control actuators are considered for evaluation: steady blowing, unsteady blowing (or pulsed jets), and zero-net-massflux blowing (or synthetic jets). Laboratory tests of each individual actuator are first performed to assess their performance and properties. The fuselage model is then equipped with these actuators distributed in eight slots forming a U-shape on the fuselage backdoor. This paper addresses the promising results obtained during the wind tunnel campaign, since significant drag reductions are achieved for a wide range of fuselage angles of attack. Moreover, a flow control strategy depending on the fuselage attitude is proposed. The link between the best actuation scheme for this attitude and the corresponding flow topology of the backdoor separation is also discussed. [ABSTRACT FROM AUTHOR]

Theophylline extended-release spheres were prepared by extrusion–spheronization of matrix granulations previously obtained by incorporation of the drug in melted Gelucire 50/02 or Gelucire 55/18. Hydrophobic Gelucire 50/02 behaved as an inert matrix and released theophylline very slowly compared with hydrodispersible Gelucire 55/18, which acted as a hydrophilic matrix. Extrusion–spheronization was more easily accomplished with Gelucire 50/02. The use of ethanol as a wetting fluid increased the rate of drug release noticeably with Gelucire 50/02 and less so with Gelucire 55/18. The use of castor oil, in conjunction with ethanol to slow down the solvent evaporation, improved extrusion and spheronization. Castor oil decreased the drug release rate with Gelucire 50/02 and increased it with Gelucire 55/18. These phenomena were explained by the different solubilities of theophylline, Gelucire 50/02, and Gelucire 55/18 in ethanol and castor oil. When microcrystalline cellulose (Avicel® CL 611) was used in the granulation matrix, extrusion was improved. The best formulation was obtained with Gelucire 55/18 and Avicel CL 611 and was wetted by a mixture of ethanol and castor oil. Regardless of the formulation, the mechanism of theophylline release appeared to be via Fickian diffusion. [ABSTRACT FROM AUTHOR]