Suchergebnisse

The increasing impact due to urban population's food supply causes a series of negative externalities related to food production, transformation and transportation. FAO and other institutions are trying to integrate traditional models of food supply with alternative ones like Urban and Peri-Urban Agriculture (UPA). Defining the drivers that motivate the participation in different types of UPA could be useful to plan more participated and effective UPA development policies. Barcelona (Spain) hosts a number of cases representing different declinations that UPA can assume. This work aims at describing the differences in terms of motivations to enter the various typologies of Urban Agriculture (UA) in Barcelona. Data were collected through semi-structured interviews to 4 groups of users representing 3 of the most widespread models of UA initiatives in Barcelona (Allotment Gardens, Community Gardens, Pla Buits.)The results showed that participation in UA is mainly motivated by relational aspects and knowledge exchange and differences exist among the various UA models. Political reasons are mostly influencing the Community Gardeners while Pla Buits users' mains motivations are related to socialising and Allotment gardeners are mainly motivated by environmental aspects. Differences in the participants' demographic characteristics also emerged. Better targeted public policies contents and communication strategies for UPA development can thus be derived by the results obtained; to this end, recommendations have been provided. Further research should broaden the range of case studies and the sample size, in order to provide a more effective and comprehensive tool for tailoring UPA developing strategies to different contexts.

Abstract
Crystalline silica (CS) is a well-known human carcinogen and freshly fractured CS is strongly held to be more toxic than aged dust. Mechanical fracturing indeed generates on CS surface a specific family of Nearly-Free Silanols (NFS), a moiety that was proved to destabilize cell membranes and initiate inflammation in vivo. During milling, silica nanoparticles are also generated, however their contribution to the overall toxicity of quartz is still largely unexplored. Nanoquartz can be synthetized via bottom-up methods, but the surface chemistry of those crystals strongly differs from nanoparticles resulting from fracturing. We report here a top-down milling procedure to obtain a nanometric quartz that shares with fractured quartz the key surface properties relevant to toxicity. Fracturing procedure was optimized by coupling dry and wet milling steps, using water as a dispersing agent, and varying milling times and rotational speeds. We obtained a set of samples that would be classified as nanomaterials under EU CLP regulation (>50% of particles in number are < 100 nm) and exhibited a strong tendency to form submicrometric agglomerates. Deagglomeration with surfactants or simulated body fluids was negligible. Partial lattice amorphization and bimodal crystallite domain size were observed, as confirmed by the presence of two distinct domains of scattering with nanometric (< 50 nm) and submicrometric (0.8-1 µm) crystallite size. A moderate membranolytic activity, which nicely correlated with the amount of surface NFS, signalled that our nanoquartz may induce inflammation in vivo. Overall, a membranolytic nanoquartz for investigating the toxic activity of nanometric silica was obtained.

The EU Bioeconomy Strategy, updated in 2018, in its Action Plan pledges an EU-wide, internationally coherent monitoring system to track economic, environmental and social progress towards a sustainable bioeconomy. This paper presents the approach taken by the European Commission's (EC) Joint Research Centre (JRC) to develop such a system. To accomplish this, we capitalise on (1) the experiences of existing indicator frameworks; (2) stakeholder knowledge and expectations; and (3) national experiences and expertise. This approach is taken to ensure coherence with other bioeconomy-related European monitoring frameworks, the usefulness for decision-making and consistency with national and international initiatives to monitor the bioeconomy. We develop a conceptual framework, based on the definition of a sustainable bioeconomy as stated in the Strategy, for a holistic analysis of the trends in the bioeconomy sectors, following the three pillars of sustainability (economy, society and environment). From this conceptual framework, we derive an implementation framework that aims to highlight the synergies and trade-offs across the five objectives of the Bioeconomy Strategy in a coherent way. The EU Bioeconomy Monitoring System will be publicly available on the web platform of the EC Knowledge Centre for Bioeconomy.