We investigate the underlying tribological mechanisms and running-in process of a semi-crystalline polymer using molecular-dynamics simulations. We subject a slab of simulated polyvinyl alcohol to a sliding contact asperity resembling a friction force microscope tip. We study the viscoelastic response of the polymer to the sliding and show both plastic and elastic contributions to the deformation, with their relative strength dependent on the temperature. As expected, the elastic deformation penetrates deeper into the surface than the plastic deformation. Directly under the tip, the polymer has a tendency to co-axially align and form a layered structure. Over time, the plastic deformation on and near the surface builds up, the friction decreases, and the polymers in the top layer align with each other in the sliding direction (conditioning).

Self‐medication (SM) is a common practice perceived by patients as harmless which can, however, entail health risks. The aim of the study was to identify drug–drug interactions (DDIs) involving SM drugs leading to adverse drug reactions (ADRs) in the National French Pharmacovigilance Database. All ADR reports from 1 January 1985 to 31 July 312018, coded as ‘interaction’ and ‘self‐medication’, were selected and studied. Patient characteristics, the level and type of interaction, and the therapeutic classes of the drugs were examined. Adverse drug reactions were analysed and classified according to the system organ classes of the Medical Dictionary for Regulatory Activities. One hundred and three reports totalling 158 ADRs (71% severe cases) were included; 153 DDIs (59.5% pharmacodynamic) involving 234 drugs were identified. The latter included 119 SM drugs (51% available on prescription), mainly analgaesics, anti‐inflammatory drugs, dietary supplements and antibiotics. Haemostasis disorders and renal failure were the most frequently reported ADRs. The analysis of reference documents raised concerns on the lack of information provided by package leaflets. In conclusion, the present study highlights the risks of medically unapproved re‐use of prescription drugs or the consumption of dietary supplements without monitoring possible interactions and ADRs. Patient awareness could be improved by more regular updates of medication package inserts.

a b s t r a c tThe full procedure for material characterisation of filament wound composite pipe is reported. Two different typologies of composite were used in order to evaluate the performance of the developed test methodology. Test samples were produced with glass/ vinylester and carbon/epoxy in tubular section by filament winding. Split disk and biaxial tests were used to evaluate the basic in plane material properties. A new design for the biaxial test was developed. The end tabs and fixture were made in order to reduce the stress concentration at the edges of the samples and to remove any possibility of sample misalignment. The influence of the sample length as well as the sample preparation was investigated and the best solution reported. Moreover, an innovative optical method was developed for the evaluation of the void content of the produced material.In addition to the basic strength data, the complete failure envelopes in the plane s 2 À t 12 were also evaluated for both materials by the use of the biaxial test procedure here developed. The experimental failure envelopes were also compared with the prediction made with some of the most common failure theories currently available. The results clearly showed the ability of the Puck criterion to accurately predict the failure envelope (especially when torsion plus axial compressive loads were applied to the samples).

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