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Against the background of the variation in populism between countries exposed in the previous chapter by Blassnig et al., this chapter will focus on article, newspaper, and country-level explanatory factors for this variation. Evidence for between-newspaper variation with respect to populist communication has already been presented elsewhere (Manucci & Weber, 2017; Rooduijn, 2014; Wettstein et al., 2018). The role of the press in a political climate of intensifying conflict among European democracies, especially in relation to financial bailouts for EU member states and the EU’s response to migration pressure, to name a few, has been criticized (Sarikakis, 2012). For instance, Tomov and Raycheva (2018) assert that for Bulgaria, populist messages are widely disseminated in the media, especially during the migrant Crisis and periods of instability. They conclude that the media disseminate populist messages without the necessary criticism, not seeking different points of view on the subject. Due to the emergence and establishment of populist parties in the political field of virtually all European democracies, political communicators might cultivate a populist discourse in the public sphere which would then also be reflected in the degree of populism in newspapers. Furthermore, existing theoretical accounts of populism and the media have suggested that we must distinguish between two forms of populist discourse in media coverage: First, populist messages stemming from political actors who communicate through the media thereby using the media as a communication channel for their ideas, and, second, populism voiced by 3 media actors themselves. For the former, Esser, Stepinska and Hopmann (2017) have coined the term “populism through the media”, and for the latter, “populism by the media”. Mazzoleni (2008) has argued that we can speak of “media populism” when journalists create Populist messages themselves – and thus become much more proactive than merely transmitting the populist statements of political actors. The aim of the chapter is to explore the weight of factors that may help us to explain varying levels of populist communication within and between countries and newspapers, such as journalistic culture of a country, editorial mission of a medium, or style of an article. We work with the same content analysis data as already presented in the previous chapter by Blassnig et al. However, we will limit ourselves to the spring 2017 data (and leave aside the spring 2016 data) because we had a slightly larger number of countries in the sample in spring 2017. The following analyses are based on 762 news stories and 632 opinion pieces published in 34 newspapers from ten western and eastern European countries between February and April 2017. For more information on the type of stories and newspapers analyzed, and for more information on our operationalization of populism and exact methodical approach, we refer to the detailed information given in the preceding chapter of this book, by Blassnig et al. more...

International audience; Gesunder humaner Knochen unterliegt einem permanenten Umbau, um sich den mechanischen Anforderungen anzupassen, Mikrofrakturen zu reparieren und das Mineralgleichgewicht zu erhalten. Der Umbauprozess der extrazellulären Matrix wird durch Osteoblasten und Osteoklasten realisiert. Eine bedeutende Rolle bei der Regulierung der Osteoklasten- und Osteoblastenaktivität wird den Osteozyten zugesprochen, welche in einem komplexen Netzwerk von Zelllakunen und Kanalikuli die extrazelluläre Matrix durchsetzen. Auf Phasenkontrast basierende hochauflösende Nano-Computertomografie erlaubt erstmals, sowohl das Zellnetzwerk als auch die direkt angrenzende mineralisierte Matrix in Untersuchungsvolumen, die hinsichtlich ihrer Größe als repräsentativ angesehen werden können, im nativen Zustand (nicht demineralisiert, nicht eingebettet) zu untersuchen.; Healthy human bone tissue undergoes a continuous remodeling process to i) repair microdamages, ii) adapt to mechanical boundary conditions, and iii) maintain a constant serum calcium level. Bone remodeling is realized by specialized bone synthesizing and resorbing cells, i. e. osteoblasts and osteoclasts, respectively. Osteocytes play an important role in the regulation of osteoblast and osteoclast activities. Osteocytes are embedded in the extracellular matrix in a complex porous lacunar-canalicular network (LCN). Recently developed high-fidelity phase-contrast nanotomography with synchrotron radiation x-ray sources enabled for the first time the simultaneous assessment of both, LCN and the adjacent extracellular mineralized matrix in close-to-native sample conditions. more...

International audience; In bone remodeling, maturation of the newly formed osteonal tissue is associated with a rapid primary increase followed by a slower secondary increase of mineralization. This requires supply and precipitation of mineral into the bone matrix. Mineral delivery can occur only from the extracellular fluid via interfaces such as the Haversian system and the osteocyte pore network. We hypothesized that in mineralization, mineral exchange is achieved by the diffusion of mineral from the lacunar-canalicular network (LCN) to the bone matrix, resulting in a gradual change in tissue mineralization with respect to the distance from the pore-matrix interface. We expected to observe alterations in the mass density distribution with tissue age. We further hypothesized that mineral exchange occurs not only at the lacunar but also at the canalicular boundaries. The aim of this study was, therefore, to investigate the spatial distribution of mass density in the perilacunar and pericanalicular bone matrix and to explore how these densities are influenced by tissue aging. This is achieved by analyzing human jawbone specimens originating from four healthy donors and four treated with high-dosage bisphosphonate using synchrotron radiation phase-contrast nano-CT with a 50-nm voxel size. Our results provide the first experimental evidence that mass density in the direct vicinity of both lacunae (p more...

International audience; The architectural properties of the osteocyte cell network provide a valuable basis for understanding the mechanisms of bone remodelling, mineral homeostasis, ageing and pathologies. Recent advances in synchrotron microtomography enable unprecedented three-dimensional imaging of both the bone lacunar network and the extracellular matrix. Here, we investigate the three-dimensional morphological properties of osteocyte lacunae in human healthy and bisphosphonate-related osteonecrotic jaw bone based on synchrotron X-ray computed tomography images, with a spatial isotropic voxel size of 300 nm. Bisphosphonate-related osteonecrosis of the jaw is a relatively new disease with increasing incidence, which remains poorly understood. A step forward in elucidating this malady is to assess whether, and how, the morphology of the osteocyte lacunar network is modified in the affected jaw tissue. We evaluate thousands of cell lacunae from five specimens of which three originate from patients diagnosed with bisphosphonate-associated osteonecrosis. In this exploratory study, we report three-dimensional quantitative results on lacunar volumes (296-502 μm3), shape (approximated by an ellipsoidal shape with principal axes a > b > c, such that a = 2.2b and a = 4c) and spatial distribution (i.e., 50% of the mineralized matrix volume is located within 12 μm to the closest lacunar boundary) at submicron resolution on such specimens. We observe that the average lacunar volumes of the bisphosphonate-related osteonecrotic jaw specimens were within the range of volumes found in the two specimens originating from healthy donors and conclude that lacunar volumes are not the key element in the course of bisphosphonate-related osteonecrotic jaw. In three out of five specimens we observe lacunar volume sizes in segmented osteons to be significantly different compared to lacunar volumes in the adjacent tissue regions. Furthermore, we quantify the number of lacunae containing small dense objects (on average 9%). In contrast to lacunar morphology we report the lacunar density (16 000-50 000 per mm3) to be different in jaw bone tissue compared to what has been reported in femoral sites. more...

International audience; Osteonecrosis of the jaw, in association with bisphosphonates (BRONJ) used for treating osteoporosis or cancer, is a severe and most often irreversible side effect whose underlying pathophysiological mechanisms remain largely unknown. Osteocytes are involved in bone remodeling and mineralization where they orchestrate the delicate equilibrium between osteoclast and osteoblast activity and through the active process called osteocytic osteolysis. Here, we hypothesized that (i) changes of the mineralized tissue matrix play a substantial role in the pathogenesis of BRONJ, and (ii) the osteocyte lacunar morphology is altered in BRONJ. Synchrotron µCT with phase contrast is an appropriate tool for assessing both the 3D morphology of the osteocyte lacunae and the bone matrix mass density. Here, we used this technique to investigate the mass density distribution and 3D osteocyte lacunar properties at the sub-micrometer scale in human bone samples from the jaw, femur and tibia. First, we compared healthy human jaw bone to human tibia and femur in order to assess the specific differences and address potential explanations of why the jaw bone is exclusively targeted by the necrosis as a side effect of BP treatment. Second, we investigated the differences between BRONJ and control jaw bone samples to detect potential differences which could aid an improved understanding of the course of BRONJ. We found that the apparent mass density of jaw bone was significantly smaller compared to that of tibia, consistent with a higher bone turnover in the jaw bone. The variance of the lacunar volume distribution was significantly different depending on the anatomical site. The comparison between BRONJ and control jaw specimens revealed no significant increase in mineralization after BP. We found a significant decrease in osteocyte-lacunar density in the BRONJ group compared to the control jaw. Interestingly, the osteocyte-lacunar volume distribution was not altered after BP treatment. more...

International audience