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This paper addresses the social issue of misinformation in six European countries by investigating how intangible factors associated with the collective evaluation of political-institutional behaviors and judgments regarding media practices and uses of online communication channels are related to citizens’ concerns about misinformation.

Based on a quantitative approach (data analysis), the study relies on data from the Eurobarometer 98.2 (2023), the official public opinion survey of European institutions. The analysis encompasses six European countries representing the pluralist-polarized (Spain, Italy and Greece) and democratic-corporatist models (Germany, Denmark and Sweden). With a multiple linear regression model, the research explores how independent variables help explain citizens' concerns regarding misinformation in each country.

The paper emphasizes three main findings: (1) for citizens in five out of six countries, the main factor associated with an increased misinformation concern is the distrust of political information on social network sites. (2) for citizens, how they evaluate the performance of traditional media relates to misinformation concerns and (3) this holds for countries categorized in pluralist-polarized and democratic-corporatist media system models.

Media managers and policymakers can leverage the insights from this research to address the social concern of misinformation.

This article adds value to existing misinformation studies by underscoring the significance of understanding how citizens’ assessments of political-institutional behaviors, journalism practices and the political use of online communication channels interconnect with the misinformation concern in both pluralist-polarized and democratic-corporatist models.

Polyamide 12 (PA12) properties meet specific requirements for various applications in the automotive and aerospace industries. Bulk specimens made of PA12 and processed via the additive manufacturing technique such as selective laser sintering (SLS) present a layered structure. In case of structural applications, the fatigue performance of SLS PA12 parts is of vital importance and fatigue response studies in these type of materials are still scarce. Therefore, the purpose of this paper is to analyse the effect of the applied load orientation on the fatigue crack propagation behaviour of the layered structure of SLS PA12.

With the aim of understanding the effect of the applied load with respect to the layer orientation on the fatigue crack growth of SLS PA12, fatigue crack growth tests were carried out at two orientations. The specimens called PARA were orientated in such a way that the applied force direction belongs to the layer plane while in the group called PERP, the tensile force direction is coincident with the build direction, that is, perpendicular to the slice. Besides, special attention has been paid to the analysis of the fracture surfaces of the specimens, linking the micromechanisms of failure with the microstructure of the material.

The SLS PA12 specimens tested with the load applied parallel to the layered structure show a little better fatigue response than those tested at perpendicular orientation. The fracture surfaces of the specimens tested at perpendicular orientation are slightly smoother than those tested at parallel orientation. Crazes are the main micromechanism of failure with a crater size of 50 microns, which coincide with the spherulite size. This indicates that the void nucleation of the crazes takes places between lamellae inside the spherulites, and consequently, the craze growth and rupture occurs mainly in a transspherulitic mode.

PA12 parts manufactured via SLS are becoming more valuable in structural elements in the automative and aeronatical fields. In such applications, fatigue performance is vital for design. Fatigue studies are scarce in literature and even more when dealing with fatigue crack growth behaviour. The value of this work is the analysis of the fatigue crack growth response of these materials taking into account the anisotropic microstructure and to get a better understanding, this behaviour is explained taking into account the micromechanisms of failure and the microstructure of the material.

Polyamide 12 (PA12) processed by the additive manufacturing technique of selective laser sintering (SLS) is acquiring a leading role in cutting-edge technological sectors pertaining to transport and biomedical among others. In many of these applications, design requirements must ensure fatigue structural integrity. One of the characteristic features of these SLS PA12 is the layer-wise structure that may influence the mechanical response. Therefore, this paper aims to assess the fatigue life behavior of PA12, focusing on the effect of the load direction with respect to the load orientation.

With the aim of analyzing the effect of the load direction with respect to the layer wise structure, fatigue tests on plain samples of SLS PA12 were carried out with the load applied parallel and perpendicular to the layer planes. The S-N stress life curves and the fatigue limit at 106 cycles were determined at room temperature and at a stress ratio of 0.1. The fracture surfaces were inspected to evaluate the damage evolution, modeled via the fracture mechanics methodology to obtain the fracture parameters.

The fatigue resistance was better when the load was applied parallel than when was applied perpendicularly to the layered structure. The analysis of the postmortem specimens evidenced three regions. The inspection of the fatigue macro crack growth region revealed that crazing was the mechanism responsible of nucleation and growth of damage till a macroscopic crack was generated, as well as of the consequent crack advancement. The calculated fracture parameters computed from the application of the fracture mechanics approach were similar to those obtained from standardized fracture tests, except when the stress levels were close to the yield strength.

The fatigue knowledge of polymers, and especially of polymers processed via additive manufacturing techniques, is still scarce. Therefore, the value of this investigation is not only to obtain fatigue data that could be used for structural design with SLS PA12 materials but also to advance in the knowledge of damage evolution during the fatigue process.

Legitimacy is the perceived appropriateness of an organisation to a social system in terms of values, norms and definitions. This research analyses how customer reviews, news media and experts’ opinions influence the legitimacy perception of high-end restaurants. The aim is to understand how collective evaluators’ opinions impact the individual legitimacy perception, linking the micro and macro levels of legitimacy. This study measures and analyses the relationships and impacts of individual (customers) and collective (experts and news media) judgments to rationalise these differences in legitimacy perceptions.

This research was conducted through a combined analysis of the reviews published in news media, online customer review platforms and experts’ publications. This study elaborates a theoretical model using partial least squares structural equation modelling analysing 246 Michelin-starred restaurants in Spain.

Our findings indicate that individual legitimacy judgments are impacted by news media but not by experts. On the contrary, experts’ evaluations positively impact news media’s evaluations. The individual legitimacy perception of the Haute Cuisine restaurant is influenced by the collective judgments of news media.

The novelty of this research states the application of the multi-level legitimacy theory to analyse the relationship between news media, online customer reviews and expert evaluations, thus the individual and collective legitimacy perceptions of Haute Cuisine restaurants. Additionally, this study adds to legitimacy theory by revealing the relationships of legitimacy judgments on micro and macro levels and analysing which and how audiences perceive organisational legitimacy.