Surgical adhesives consist on an attractive alternative to suturing or stapling since they can accomplish other tasks, such as haemostasis and the ability to seal air leakages. The application of adhesives would also reduce the surgeries procedure time since they represent an easier and faster method to establish tissue adhesion. The aim of this work was the development of a biodegradable urethane pre-polymer that presents the capacity of reacting with the amino groups present in the biological molecules. Urethanes based on polycaprolactone diol (PCL) were synthesized by reaction of the molecule either with isophorone diisocyanate (IPD-isocyanate) or hexamethylene diisocyanate (HDI-isocyanate). The characterization of the materials was accomplished by: ATR-FTIR (Attenuated Total Reflectance-Fourier Transform Infrared), determination of swelling capacity, stability of NCO groups in the presence of humidity conditions, reaction with aminated substrates (as a simulation of the living tissues) and determination of surface energy by contact angle measurement. The haemocompatibility of the PU was also evaluated by thrombosis and haemolysis tests.

An experimental programme was carried out on the shear strength behaviour of sandy and clayey soils reinforced with short, randomly distributed, polypropylene (PP) microfibres. The influence of fibre texture, fibre content, fibre length and normal stress level was investigated by means of direct shear tests. The best procedure to mix the soil with the fibres in order to achieve homogeneous and isotropic samples is described. This study shows that fibres increase the shear strength and significantly modify the shear stress displacement behaviour of the tested soils. Shear strength increases with increase in fibre content, fibre length and displacement. No appreciable advantage is achieved by using crimped (texturised) fibres as far as shear strength is concerned. Furthermore, mixture is achieved with greater difficulty when compared with straight fibres. There is an increase in both the apparent cohesion and the angle of shearing resistance of soils, owing to the short PP microfibres. The fibre contribution is especially significant for low normal stress levels. Despite the occurrence of some fibre damage, damaged fibres are still suitable for reinforcement.

Fourth-generation ‘pod’ e-cigarette devices have been driven by technological advances in electronic atomization of the e-liquid. Use of microporous ceramic as a wicking material improves heating efficiency, but how it affects the chemical emissions of these devices is unclear. We assessed the emissions of a pod e-cigarette with innovative ceramic wick-based technology and two flavoured e-liquids containing nicotine lactate and nicotine benzoate (57 and 18 mg mL−1 nicotine, respectively). Among the studied harmful and potentially harmful constituents (HPHCs) listed by the US FDA and/or WHO TobReg, only 5 (acetone, acetaldehyde, formaldehyde, naphthalene and nornicotine) were quantified at levels of 0.14 to 100 ng puff−1. In the combustible cigarette (Kentucky reference 1R6F), levels were from 0.131 to 168 µg puff−1. Nicotine levels ranged 0.10–0.32 mg puff−1 across the 3 study products. From the 19 proposed HPHCs specifically of concern in e-cigarettes, only 3 (glycerol, isoamyl acetate and propylene glycol) were quantified. The low/undetectable levels of HPHCs reflect not only the optimal operating conditions of the e-cigarette, including an efficient supply of e-liquid by the ceramic wick without overheating, but also the potential of the e-cigarettes to be used as an alternative to combustible cigarettes.

Scale models are a powerful means of studying engineering problems; they are versatile because it is easier to make alterations, relatively inexpensive because less space is required, as well as requiring less time for construction, instrumentation, and testing. This paper describes the work carried out in an experimental study on the behaviour of geotextile-reinforced, brick-faced soil retaining walls by means of one-fifth (1/5) scale models under normal gravity (1g) and compares the model results with data from a previous research programme on prototype-scale walls. The modelling was based on the principles of similarity and dimensional analysis. An experimental apparatus was designed and suitable materials were selected taking into account the modelling requirements. Comparisons between the model results and those obtained in previous prototype-scale tests were undertaken. An acceptable degree of agreement was achieved.

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