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A major disadvantage of polymer-based composite materials is their poor performance when exposed to relatively high heat flux. At temperatures typically above 300–400 °C, the organic matrix decomposes releasing heat, smoke, and toxic volatiles, jeopardising the composite mechanical performances. The heat flux resistance of composites can be improved by integrating protective coatings on their surface. In the present work, graphene nanoplatelet (GNP) films are employed as thermal barrier coatings (TBCs) to mitigate the thermal degradation of Carbon Fibres Reinforced Plastic (CFRP). The films were bonded onto the heat-exposed surface of CFRP laminates. Laser spot heating tests, with different laser power densities (25–150 kW/m2), were adopted to assess the effectiveness of the coating. The effect of the thickness of the protective layer has been tested too, by changing the number of layers (from 1 to 2 layers). From the results, a significant reduction in the temperatures and damages were observed. Moreover, the damage extension and residual mechanical performances of exposed samples have been assessed as a function of the power density and the protection level. A significant improvement of the post-heat flexural moduli and a significant reduction of the damaged areas have been obtained in laminates protected with high-loaded graphene nanoplatelet films.

Il presente lavoro si pone l’obiettivo di ricercare quali siano i differenti livelli di governance impegnati nell’implementazione di pratiche di sostenibilità aziendale e come questi siano influenzati e, allo stesso tempo, influenzino distinti contesti istituzionali. A tal fine, viene offerta una revisione della letteratura interpretando la ricerca con due chiavi di lettura, attinenti rispettivamente agli studi di International Corporate Governance e Institutional Theory. Vengono utilizzate due chiavi di lettura distinte per analizzare come, le multinazionali, coinvolte in strutture di governance multilivello e, operanti in contesti istituzionali caratterizzati da sistemi di capitalismo differenti, possano implementare pratiche sostenibili all’interno delle loro catene di fornitura. In particolar modo, il presente studio investiga fino a che punto i livelli di governance privati e civili possano sostituire o integrare la governance pubblica nelle sfide di sostenibilità globale. La ricerca, ancora in fieri, ha dunque lo scopo di costruire un framework integrativo che metta alla luce le possibili intersezioni concettuali e teoriche dei due flussi di studi e quale sia la loro interazione nel percorso verso la sostenibilità aziendale.

Objectives To test whether Mediterranean-type Diet (MeDi) at age 70 years is associated with longitudinal trajectories of total brain MRI volume over a six-year period from age 73 to 79. Design Cohort study which uses a correlational design. Setting Participants residing in the Lothian region of Scotland and living independently in the community. Participants A relatively healthy Scottish sample drawn from the Lothian Birth Cohort 1936. Measurements Total brain volume measurements were available at ages 73, 76 and 79 (N ranged 332 to 563). Adherence to the MeDi was based on food frequency questionnaire data collected three years before the baseline imaging scans, and was used in growth curve models to predict the trajectory of total brain volume change. Results No association was found (p>.05) between adherence to the MeDi at age 70 and total brain volume change from 73 to 79 years in minimally-adjusted (sex) or fully adjusted models controlling for additional health confounders. Conclusions Variation in adherence to the MeDi was not predictive of total brain atrophy over a six-year period. This suggests that previous findings of dietary associations with brain volume are not long lasting or become less important as ageing-related conditions account for greater variation in brain volume change. More frequent collection of dietary intake data is needed to clarify these findings.

Background Being overweight or obese following breast cancer diagnosis can increase cancer recurrence and mortality, so effective interventions for weight loss in this group could enhance survival. A pilot randomised controlled trial was conducted to assess whether a weight loss programme comprising generic Weight Watchers® referral offered to women treated for breast cancer with or without additional breast cancer-tailored dietetic support is feasible and shows promise for improving weight and quality of life (QoL). Methods Participants were randomly allocated to 3 groups: Weight Watchers® referral (for 12 sessions of meetings and digital tools) plus 5 breast cancer-tailored dietitian-led group support sessions (WW Plus: n = 14), Weight Watchers® referral only (WW: n = 16) or control (Weight Watchers® referral after 3 months, n = 15). Feasibility was assessed based on retention rate, recruitment and randomisation process, meeting attendance, suitability of the setting and outcome measurement tools, unintended consequences, cost and observations of the dietetic sessions. Outcomes were measured at 0, 3 (‘trial exit’) and 12 months post intervention. Results The response rate to the invitation was 43% (140/327) of whom 58 were eligible and 45 (median age 61.0 years; body mass index 30.2 kg/m2) were randomised. Data from 38 (84%) and 30 (67%) participants were available at trial exit and 12 months respectively. Feasibility issues included slow recruitment process, lack of blinding throughout, weighing scales not measuring > 150 kg, lack of clear instructions for completing QoL questionnaire and workload and time pressures in delivering dietetic sessions. Participants had good attendance rate at group meetings and no serious unintended consequences were reported. WW Plus was most expensive to run. Mean (95% CI) weight change at trial exit was − 3.67 kg (− 5.67, − 2.07) in WW Plus, − 6.03 kg (− 7.61, − 4.44) in WW group and + 0.19 kg (− 1.45, + 1.83) in control group. About 40% of the WW Plus, 64% of the WW group and 56% of the control group lost ≥ 5% of their baseline weight by 12 months. All groups showed promise for improving QoL at trial exit but only the WW group maintained significant improvements from baseline at 12 months. Conclusions The trial procedures were feasible, with some modifications. This pilot trial indicates the benefits of providing free WW vouchers for weight loss maintenance and improving QoL but provided no evidence that including additional dietetic support would add any extra value. Further research with WW with long-term follow-up should be undertaken to assess weight loss sustainability and benefit on health outcomes in this patient group. Trial registration ISRCTN-29623418. Electronic supplementary material The online version of this article (10.1186/s40814-019-0405-x) contains supplementary material, which is available to authorized users.