A predominantly positive view is shown in engagement literature in terms of positive actor engagement (PNE) expressions and outcomes. However, business practices indicate that the understanding of actors being negatively engaged is important. Yet a few studies in marketing, which attempt to conceptualise negative actor engagement (NAE), do not have a consensus as for whether NE and PE are reciprocal or NE is a distinct construct with a different nomological network and process. The purpose of this study is to conceptualise and operationalise NAE. Built on Li et al.’s (2018) conceptualisation of actor engagement valence, this paper follows Churchill’s (1979) methods of scale development and operationalises the construct of NAE. By developing and validating a NAE scale in specific online learning servcie platforms, we address this identified literature gap. Specifically, this study derives four NAE dimensions, including annoyance, anxiety, futitlity and failed expectation, which we proceed to validate within a nomological net of conceptual relationships in relation to the engagement behaviours (learning, sharing and endorsing). We conclude with an overview of key managerial and scholarly implications arising from this research. This marks the first study in the marketing discipline to operationalise NAE.

Laser pyrolysis is a very suitable method for the synthesis of a wide range of nanoparticles. A pilot unit based on this process has been recently developed at CEA. This paper reports results showing the possibility to produce SiC and nanoparticles at rates of respectively 1 and 0.2 kg/h and also the possibility to adjust the mean grain size of the particles and their structure by changing the laser intensity and reactants flow rates. First tests of liquid recovery have been also successfully performed to limit the risks of nanoparticles dissemination in the environement during their recovery.