Van Aelst Research Articles

Dye Analysis of a 17th-Century Mattens Workshop Tapestry Based on Raphael’s Drawing, The Miraculous Draught of Fishes

This paper describes the identification of dyes on fifty yarn samples from a tapestry created by the well-known 17th-century Flemish workshop of the Mattens family. The design of the tapestry is based on the first of ten drawings known as the Acts of the Apostles by the famed 16th-century Italian painter Raphael. The drawings were commissioned by Pope Leo X and translated into tapestries by Pieter van Aelst; these original tapestries are still in the collection of the Vatican Museums. The present work was reproduced over a century later from the original drawing and is one in a possible set of nearly fifty known copies of the original tapestry cycle. Most of the Mattens yarn samples were found to be dyed by weld, indigo, and madder, as well as a few using brazilwood and lichen, but no insect dyes were detected. A significant finding in the present study was the detection of the dye component pseudoindirubin 1, alongside indigotin and indirubin, as well as yarns that only yielded the latter two dyes. The implication of using this new marker as objective evidence of the use of both woad and most likely Asian indigo is explored. The historical and conservation significance of the dyestuffs identified is also discussed.

Non-asymptotic robustness analysis of regression depth median

The maximum depth estimator (aka depth median) (βRD∗) induced from regression depth (RD) of Rousseeuw and Hubert (1999) is one of the most prevailing estimators in regression. It possesses outstanding robustness similar to the univariate location counterpart. Indeed, βRD∗ can, asymptotically, resist up to 33% contamination without breakdown, in contrast to the 0% for the traditional (least squares and least absolute deviations) estimators (see Van Aelst and Rousseeuw (2000)). The results from Van Aelst and Rousseeuw (2000) are pioneering, yet they are limited to regression-symmetric populations (with a strictly positive density), the ϵ-contamination, maximum-bias model, and in asymptotical sense. With a fixed finite-sample size practice, the most prevailing measure of robustness for estimators is the finite-sample breakdown point (FSBP) (Donoho and Huber, 1983). Despite many attempts made in the literature, only sporadic partial results on FSBP for βRD∗ were obtained whereas an exact FSBP for βRD∗ remained open in the last twenty-plus years. Furthermore, is the asymptotic breakdown value 1/3 (the limit of an increasing sequence of finite-sample breakdown values) relevant in the finite-sample practice? (Or what is the difference between the finite-sample and the limit breakdown values?). Such discussions are yet to be given in the literature. This article addresses the above issues, revealing an intrinsic connection between the regression depth of βRD∗ and the newly obtained exact FSBP. It justifies the employment of βRD∗ as a robust alternative to the traditional estimators and demonstrates the necessity and the merit of using the FSBP in finite-sample real practice.

How to paint a bouquet: MA‐XRF analysis of 17th century Netherlandish flower still lifes from the Mauritshuis

AbstractThe Mauritshuis (The Hague, The Netherlands) owns a large collection of 17th‐century still lifes, of which a significant portion depicts floral arrangements. As part of a still life cataloguing project, 19 of the flower still lifes have been examined using a wide range of scientific technologies, including MA‐XRF scanning. This paper will discuss how MA‐XRF analysis has significantly improved our understanding of the way artists prepared their compositions. It became apparent that there are several ways in which artists planned their painted bouquets. Early 17th‐century still life painters such as Baltahasar van der Ast used detailed underdrawings, which they followed during the painting stage. Artists from Antwerp, like Daniël Seghers started their paintings by making ‘abstract’ compositions of coloured circles and ovals. This method was picked up by Jan Davidsz, de Heem, who was working in both Antwerp and Utrecht. De Heem's pupils Abraham Mignon and Maria van Oosterwijck used a similar method, but other still life specialists such as Van Aelst and Rachel Ruysch planned their compositions differently.

Abstract 62: Untangling the connection between stress and metastatic breast cancer

Abstract There is emerging evidence that exposure to chronic stress is associated with increased risk of metastasis and poor survival in cancer patients. However, the underlying molecular and cellular mechanisms responsible for the effects of stress on tumor progression remain unclear. To determine how stress promotes metastasis, we established new mouse models in which multiple chronic stress exposure promoted breast cancer metastasis to the lungs. We found that chronic stress generates a pro-metastatic lung microenvironment with e.g., reduced T cell infiltration and increased extracellular matrix (ECM) deposition and neutrophil infiltration. Among them, neutrophils were required for these changes as their depletion abolished the pro-metastatic effects of stress and normalized the lung tumor microenvironment. Mechanistically, we analyzed neutrophils from chronically stressed mice and identified dramatically altered transcriptomes, including increased expression of several glucocorticoid receptor regulated genes. Phenotypically, neutrophils from stress exposed mice exhibited increased ROS production, and an increased ability to inhibit T cell activation and to form spontaneous neutrophil extracellular traps (NETs). The stress-associated changes to neutrophils were dependent on glucocorticoid receptor (GR) signaling as neutrophil-specific GR knockout mice showed no increase in NET-formation, a normalized lung microenvironment and no increase in lung metastasis upon stress exposure. Among the changes in the neutrophils caused by stress exposure, we found that the formation of pro-metastatic NETs was critical as directly digesting NETs with DNase I prevented stress-induced metastasis and normalized the lung microenvironment. In sum, this work shows that chronic stress exposure causes a glucocorticoid-mediated increase in NET formation and that NETs are critical drivers in the establishment of a stress-induced, metastasis-promoting microenvironment. Targeting NETs could be an important strategy to prevent metastatic recurrence in cancer patients, many of whom will experience stress due to their cancer diagnosis and subsequent treatments. Citation Format: Xue-Yan He, David Ng, Yuan Gao, Evdokia Michalopoulou, Shanu George, Jose M. Adrover, Lijuan Sun, Jean Albrengues, Ledong Wan, Xiao Han, Christopher Vakoc, Linda Van Aelst, Mikala Egeblad. Untangling the connection between stress and metastatic breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 62.

Stepwise photoassisted decomposition of carbohydrates to H2

Stepwise photoassisted decomposition of carbohydrates to H2

People want to see people? Personalization on Facebook as a tool for corporate communications

PurposeSocial networks were created to connect with friends. Therefore, communication in social networks allows addressing individual contacts of each user and is often rather private by nature. Organizations can use this to communicate frequently and personally with their stakeholders. Therefore, this study investigates how organizations use personalization in their social media communication.Design/methodology/approachThis study uses a quantitative content analysis of Facebook posts from ten large companies (N = 500). The posts were analyzed regarding the sub dimensions of personalization, individualization and privatization, as well as type of post, tonality, emotions, user reactions and topics.FindingsCompanies at least partially personalize their communication on Facebook. Overall, 28% of all posts were personalized. Personalized posts were almost always positive regarding tonality and mostly positive regarding emotions. While the personalized posts in this study have fewer user reactions than non-personalized posts, they still have a rather high absolute number of reactions. Regarding personal characteristics, results show that professional competence and appearance were mainly addressed. Concerning privatization, only very few posts showed an individual in a private setting.Originality/valueThe present work gives an overview of how personalized posts differ from non-personalized posts and looks at depicted individuals as well as the use of private elements. By applying the conceptualization of Van Aelst et al. (2012) and by looking at organizations’ use of personalization on the social media platform Facebook, it sheds light on an area that has not been the center of attention so far and helps to expand the current state of personalization research.

Raphael: The Power of Renaissance Images: The Dresden tapestries and their impactApostles in Prussia: The Raphael tapestries of the Bode-MuseumThe Raphael Cartoons

During the Raphael quincentenary, three books appeared on the cartoons and tapestries of the Acts of the Apostles. These are reviewed here by the former senior curator of paintings at the Victoria and Albert Museum, who co-curated an earlier exhibition there on these works (see Mark Evans and Clare Browne, with Arnold Nesselrath (eds.), Raphael: Cartoons and tapestries for the Sistine Chapel (London, 2010)). Raphael was commissioned in 1515 by Pope Leo X to paint ten monumental cartoons in gouache on paper for tapestries of the lives of St Peter and St Paul. Their weighty draped figures were inspired by Masaccio and Filippo Lippi’s frescos at the Brancacci Chapel in Florence. By 1516–18 Raphael’s designs had already been reproduced as prints. The tapestries of wool, silk and gilt-wrapped thread were woven between 1517 and 1521 at the Brussels workshop of Pieter van Aelst. These were displayed on special occasions...

How the European in vitro diagnostic regulation could negatively impact the European response to the next pandemic: an urgent call for action before May 2022

Abstract The Corona Virus Disease 2019 (COVID-19) pandemic has demonstrated that the ability for laboratories to quickly set up and implement labdeveloped tests (LDTs) is essential to respond to an emerging health crisis. The Regulation on in vitro diagnostic medical devices (IVDR) could, however, profoundly impact our ability to respond to a future pandemic since the IVDR could significant restrict the use of LDTs. We address using the example of the current pandemic a number of LDT implementing issues problems which should be addressed. We conclude that the COVID-19 pandemic illustrates that commercial tests cannot cover all patient needs under any given circumstance and that sufficient degrees of freedom for laboratories to ensure their expertise to develop and implement LDTs ultimately benefit European citizens.

Ophn1 regulation of prefrontal inhibition: A mechanism for stress susceptibility in intellectual disability

Wang etal. (2021) characterize the molecular, cellular, and circuit-level role of Oligophrenin-1 in prefrontal parvalbumin interneurons, demonstrating that loss of Ophn1 function in these neurons is a mechanism for increased susceptibility to stress in intellectual disability caused by OPHN1 mutations.

Personalization (Election Campaign Coverage)

Personalization (Election Campaign Coverage)

La Virgen y el Niño en la huida a Egipto de Paul Coecke van Aelst

En este artículo se estudia e identifica un original de La Virgen y el Niño en la huida a Egipto, tradicionalmente atribuido a Pieter Coecke van Aelst, como obra de su hijo Paul Coecke van Aelst, quien solía copiar pinturas de Jan Gossaert incluyendo algunos detalles personales.

The Guthrie Boulder: A Forgotten Monument to Anesthesia in Chicago.

The Guthrie Boulder: A Forgotten Monument to Anesthesia in Chicago.

Generational Patterns of Digital News Consumption

Digital high-choice media environments (Prior, 2007; Van Aelst et al., 2017) lead to fragmented and polarized news consumption. The concept of news repertoires was introduced to analyze media use in a cross-media environment. News repertoires were found to be diverse across countries, to be dependent on age groups, socioeconomic status, and to have effects on political knowledge and participation (Diehl et al., 2018; Edgerly et al., 2018; Strömbäck et al., 2018; Wolfsfeld et al., 2016). The aim of this study is to identify different news repertoires in Croatia and to test the effects of generational belonging and socioeconomic status on the formation of these repertoires. It has been shown over time that age and political interest are more important predictors of increasingly diversified and polarized news consumption (Bergström et al., 2019; Strömbäck et al., 2013). This study discusses the interplay of sociodemographic factors and political interest in driving news consumption across different generations. The analysis is based on data from Reuters Digital News Survey conducted in Croatia in 2018. Latent class analysis is used to identify news repertoires and the covariates which form them. The analysis resulted in identifying five news repertoires: minimalists, digital-born users, traditionalists, commercial media users and eclectics.

Who’s Elite and How the Answer Matters to Politics

In How Political Actors Use the Media, Van Aelst and Walgrave (2017) argue that to understand the role of media in politics, we should look beyond their influence on politics (mediatization) and ex...

A Fresh Perspective on Politicians and the Media

We need to know more about how political actors use the media, so say Peter Van Aelst and Stefaan Walgrave to us—and so say I to them as well!Their book, How Political Actors Use the Media, present...

Zea mays L. hybrids kernels evaluated by image analysis tools

Received: 2018-06-07 | Accepted: 2018-06-19 | Available online: 2018-06-30 https://doi.org/10.15414/afz.2018.21.02.77-83 The aim of this study was to distinguishing between kernels of maize hybrids by the use of image analysis tools. We analyzed 10 registered Zea mays L. hybrids (5 – dent, 2 – semi-flint to flint, and 3 – semi-flint to dent type). Different parameters on ventral, dorsal, corolla side, and lateral side cross section of kernel were measured. Sample per each hybrid comprised 50 maize kernels. Acquired bio-images were processed by software Zeiss AxioVision Rel. 4.8. We analyzed the segmented regions of interest on the kernels. The data for area (mm 2 ), height and width (mm) were gathered from these regions. The hybrid ZE EDOX significantly differed (p < 0.05) from all other hybrids almost in all traits. It is the hybrid with the smallest area of the whole kernel, floury endosperm proportion, and depressed part on corolla. The new trait the area of the depressed part on the kernel corolla was measured. The hybrids with smaller proportion of floury endosperm had smaller area of depressed part, and vice versa. The image analysis methods can usefully contribute to selection of proper hybrids for different types of use. Keywords: maize, Zea mays L., kernel, image analysis References BLASCHKE, T. et al. (2014) Geographic Object-Based Image Analysis – Towards a new paradigm. In ISPRS Journal of Photogrammetry and Remote Sensing, vol. 87, pp. 180–191. https://doi.org/10.1016/j.isprsjprs.2013.09.014 DE CARVALHO, M. L. M., VAN AELST, A. C., VAN ECK, J. W., HOEKSTRA, F. A. (1999) Pre-harvest stress cracks in maize (Zea mays L.) kernels as characterized by visual, X-ray and low temperature scanning electron microscopical analysis: effect on kernel quality. In Seed Science Research, vol. 9, pp. 227–236. DELL´AQUILA, A. (2006) Computerised seed imaging: a new tool to evaluate germination quality. In Communications in Biometry and Crop Science, vol. 1, no. 1, pp. 20–31. ERASMUS, C. (2003) Maize kernel translucency measurement by Image Analysis and its relationship to vitreousness and dry milling performance. PhD thesis. Pretoria: University of Pretoria. FOX, G. and MANLEY, M. (2009) Hardness methods for testing maize kernels. In Journal of Agricultural and Food Chemistry, vol. 57, no. 13, pp. 5647–5657. doi: https://doi.org/10.1021/jf900623w GLASBEY, C. A. and HORGAN, G. W. (2001) Image analysis in agriculture research. In Quantitative Approaches in System Analysis, special issue, vol. 23, pp. 43–54. GUELPA, A., DU PLESIS, A., KIDD, M., MANLEY, M. (2015) Nondestructive estimation of maize (Zea mays L.) kernel hardness by means of an X-ray micro-computed tomography (μCT) density calibration. In Food and Bioprocess Technology, vol. 8, no. 6, pp. 1419–1429. JANDA, J. and MICHALEC, V. (1982) Mayze. Bratislava: Priroda. 408 p. MUTTERER, J. and ZINCK, E. (2013) Quick‐and‐clean article figures with FigureJ. In Journal of Microscopy, vol. 252, pp. 89– 91. doi: https://doi.org/10.1111/jmi.12069 ROBUTTI, J. L., HOSENEY, R. C. and WASSOM, C. E. (1974). Modified opaque-2 corn endosperms. ll. Structure viewed with a scanning electron microscope. In American Association of Cereal Chemists, vol. 51, pp. 173–180. RODRIGUEZ-PULIDO, F. J. et al. (2012) Ripeness estimation of grape berries and seeds by image analysis. In Computers and Electronics in Agriculture, vol. 82, pp. 128–133. SCHINDELIN, J., RUEDEN, C. T., HINER, M. C., ELICEIRI, K. W. (2015) The ImageJ ecosystem: An open platform for biomedical image analysis. In Mol. Reprod. Dev., vol. 82, pp. 518–529. doi: https://doi.org/10.1002/mrd.22489 UCHIDA, S. (2013) Image processing and recognition for biological images. In Development, growth and differentiation, vol. 55, pp. 523–549. doi: https://doi.org/10.1111/dgd.12054 WATSON, S. A. (1987) Structure and composition. In WATSON, S. A. and RAMSTAD, P. E. (Eds.). Corn chemistry and technology. St. Paul: American Association of Cereal Chemists. WIWART M. et al. (2012) Identification of hybrids of spelt and wheat and their parental forms using shape and color descriptors. In Computers and Electronics in Agriculture, vol. 83, pp. 68–76. https://doi.org/10.1016/j.compag.2012.01.015

Chapter 8 – Media reporting of migrants and migration

Chapter 8 – Media reporting of migrants and migration

Henk Schat.

Henk Schat.

At the Interface of Social Media Analytics, Big Data and Social Movements: Research Challenges

Social media is being employed to build support for social, economic, and political justice (Selander et al. 2016; Vaast et al. 2014) in movements such as occupy Wall Street, violence against women's movement and global sustainability movement. These movements have used social media in ways that goes beyond simple communications. As social media allows people to produce and share user generated content, they enable a certain set of affordances of these technologies (Bharati et al 2015; Bharati et al 2014). The social media affordances, available to both collective and individual actors, translate into capabilities afforded to social movements (Tufecki 2014). Research on connective action has examined the effects of digital action repertoires on interaction and engagement such as in the Tea Party and Occupy movements (Agarwal et al. 2014; Selander et al. 2016). Social media can also facilitate mobilization of movement and participation by new volunteers and oftentimes provides a transnational character by diffusing actions beyond the virtual (Van Laer and Van Aelst 2010). Conversation, an essential part of social movements, shapes “social life by altering individual and collective understandings, by creating and transforming social ties, by generating cultural materials that are then available for subsequent social interchange, and by establishing, obliterating, or shifting commitments on the part of participants&x201D; (Tilly 2002, p. 122). In a personal interaction that involves repeated organized interactions between individuals, typically, leads to shared values and trust. The role of social media technologies in furthering this conversation has to be studied and its' influence on social movement ascertained. A few scholars have started to investigate social media affordances and capabilities, especially focused on discourse, during contentious collective action. Still the research has been limited to studying mechanisms of participation, development of a sense of collective identity, creation of community, and framing of political discourse (Farrell 2012; Garrett 2006). Social media data on social movements can involve impersonal “like&x201D; and “share&x201D; to more engaged conversations. Twitter, Instagram, Facebook, and YouTube offer a wide communicative and discourse reach in networks with text, image, audio, and video data. This social media based big data, consisting mostly of unstructured data, comes in the form of social media posts, digital pictures and videos. The symposium will discuss how formal organizational structures and practices might be integrated with social media capabilities to reinforce and enhance social movement organizations as leaders in social change movements. It will explore the characteristics of social media discourse and assess the dynamics of social movements and, subsequent, impact on real-world protests. The symposium will also demonstrate how discourse analysis can be applied visually in order to understand communication patterns. The panel symposium will focus on theoretical and methodological challenges of social media analytics, big data and social movements. Panelists will engage the audience in an interactive discussion on: 1) Theoretical challenges: a. How and why are social movement recruitment and engagement mechanisms being impacted as a result of social media? b. How do we advance theory on social media and social movements when we are overwhelmed with social media based big data? c. What approach should we undertake if big data analysis contradicts most theories on social media and social movements? d. How do we address the issue of generalizability of social media and social movement research when data collection was limited to one social media platform, albeit involving big data? 2) Methodological challenges: a. What methodological approaches have worked in the analysis of social media, big data and social movements? b. How can discourse analysis be applied visually in order to understand communication patterns evident in social media-based big data? c. How can we employ social media analytics to investigate image and video data? d. What combinations of qualitative and quantitative methodologies be employed for big data and social media analytics in the context of social movements? e. What are the limitations of quantitative data analysis techniques, such as structural equation modeling, because of an extremely large sample size? f. What are the limitations of qualitative data analysis techniques as they become extremely labor intensive and, maybe even, impractical because of big data?

Generation Y and the World of Work in the Future

IntroductionEvery generation has its unique defining characteristics, and Generation Y, also known as Digital Natives, Net Generation, Generation@ or Millennials, is the generation which has grown up with the Internet. Generation Y is the term given to the generation succeeding Generation X and preceding Generation Z. Hence, Generation Y refers to a specific generation born from the early 1980s to the mid-1990s. However, experts neither agree on an exact year when the era of Generation Y started nor do they claim a distinct year to mark an endpoint of the era. However, what definitely sets apart Generation Y from their forerunners is the fact that they grew up alongside mediatization and globalization.The definition of a whole generation inevitably inspires passionate debates as individuals are different concerning their social, cultural and economic backgrounds. Some scientists even refuse to accept the concept of generations. In their eyes it is virtually impossible to apply one definition to all as it comprises a range of diverse people. However, according to scientific literature portraying Generation Y, there are some characteristics which individuals of Generation Y obviously have in common and which set them apart from previous generations. Individuals of Generation Y differ in terms of attitudes, values and behavioral patterns from their predecessors. As a consequence, they tend to question strict hierarchies and entrenched structures. Although they are described as ambitious and determined, they appreciate a proper work-life balance. Unlike previous generations they are no longer willing to sacrifice their family lives to their careers. Hence, they expect employers to ensure the reconcilability of family and working life. Having grown up in a multioption society, Generation Y expresses a great need for individualism and flexibility, not only in their private lives, but also in their working environments.As Generation Y ascends the career ladder now and in the years to come, they are already influencing German companies and human resources managers. Especially against the backdrop of an anticipated labor shortage, Generation Y and their attitudes will shape the German economy. This article will contribute to an analysis of Generation Y, not only in terms of their chances and choices, but also by identifying the stumbling blocks which might stand in their way when it comes to making a career.Theoretical frameworkIn recent years, mediatization has emerged as an important concept and theoretical framework for considering the interplay between media, culture and society. Some of the most prevalent researchers in mediatization are noted to be Andreas Hepp, Stig Hjarvard, Friedrich Krote and Knut Lundby (Lunt and Livingstone, 2016). Although the idea of mediatization dates back to the beginning of the 20th century, the current concept was not outlined before the last decade (Ekstrom et al., 2016; Hepp, 2013). However, the researchers have not yet reached a consensus about a comprehensive definition of mediatization (Deacon and Stanyer, 2014; Hepp et al., 2015). On the one hand, there are researchers who consider that the concept is based on the institutionalist tradition. On the other hand, there are those who argue that mediatization is based on the socio-constructivist tradition (Hepp, 2013; Birkner, 2015).If mediatization was based on institutionalism, larger and smaller scale institutions, agencies and organizations would shape and regulate the communicative practices of media and the audience would need to adapt to the media and its objectives (Deacon and Stanyer, 2014; Hepp, 2013; Stromback and Van Aelst, 2013).This understanding is contrasted by disciples of the socio-constructivist tradition. One distinctive feature of the socio-constructivist approach is that it takes into account the change of the audience as well. The media and the media audience are both constantly changing and this approach aims to relate these changes to each other (Hepp, 2013; Hepp et al. …