A comparative analysis of transcription factor expression during metazoan embryonic development

During embryonic development, a complex organism is formed from a single starting cell. These processes of growth and differentiation are driven by large transcriptional changes, which are following the expression and activity of transcription factors (TFs). This study sought to compare TF expression during embryonic development in a diverse group of metazoan animals: representatives of vertebrates (Danio rerio, Xenopus tropicalis), a chordate (Ciona intestinalis) and invertebrate phyla such as insects (Drosophila melanogaster, Anopheles gambiae) and nematodes (Caenorhabditis elegans) were sampled, The different species showed overall very similar TF expression patterns, with TF expression increasing during the initial stages of development. C2H2 zinc finger TFs were over-represented and Homeobox TFs were under-represented in the early stages in all species. We further clustered TFs for each species based on their quantitative temporal expression profiles. This showed very similar TF expression trends in development in vertebrate and insect species. However, analysis of the expression of orthologous pairs between more closely related species showed that expression of most individual TFs is not conserved, following the general model of duplication and diversification. The degree of similarity between TF expression between Xenopus tropicalis and Danio rerio followed the hourglass model, with the greatest similarity occuring during the early tailbud stage in Xenopus tropicalis and the late segmentation stage in Danio rerio. However, for Drosophila melanogaster and Anopheles gambiae there were two periods of high TF transcriptome similarity, one during the Arthropod phylotypic stage at 8-10 hours into Drosophila development and the other later at 16-18 hours into Drosophila development.Comment: ~10 pages, 50 references, 6+3 figures and 5 table

Lagrangian coherent structures and plasma transport processes

A dynamical system framework is used to describe transport processes in plasmas embedded in a magnetic field. For periodic systems with one degree of freedom the Poincar\'e map provides a splitting of the phase space into regions where particles have different kinds of motion: periodic, quasi-periodic or chaotic. The boundaries of these regions are transport barriers; i.e., a trajectory cannot cross such boundaries during the whole evolution of the system. Lagrangian Coherent Structure (LCS) generalize this method to systems with the most general time dependence, splitting the phase space into regions with different qualitative behaviours. This leads to the definition of finite-time transport barriers, i.e. trajectories cannot cross the barrier for a finite amount of time. This methodology can be used to identify fast recirculating regions in the dynamical system and to characterize the transport between them

Relevant market delineation with the use of strategic business information.

In his paper a, overview of methods used in antitrust analysis to delineate relevant markets is provided and shortcomings are pointed out. A practical methodology to delineate relevant geographical and product markets is developed, starting from the theoretical definition of a relevant antitrust market. Based on criteria used by business strategists in segmenting markets, the new methodology makes use of strategic information on the position of a company and its competitors in a specific industry sector to delineate relevant markets. The usefulness of the new methodology is illustrated from the European truck industry.

Grote verhalen en grote gebaren: Nationalisme en de restauraties van de Alte Nationalgalerie en het Rijksmuseum

Dit onderzoek bevraagt de rol van nationalisme in de Alte Nationalgalerie en het Rijksmuseum. Deze musea zijn in de negentiende eeuw gebouwd om nationaal besef bij burgers te versterken. Het onderzoek richt zich dan ook specifiek op wat hiervan teruggehaald is bij de restauraties van respectievelijk 1998-2001 en 2003-2013. Hoe architectuur, inrichting en omgang met de collectie nationaal besef kunnen stimuleren, wordt bestudeerd aan de hand van archiefmateriaal als jaarverslagen, correspondentie en beleidsplannen, maar ook op basis van interviews en bezoeken aan de musea. Dit alles wordt geplaatst binnen een kader van auteurs die de laatste jaren steeds meer aandacht besteden aan de rol van nationalisme in (kunst)geschiedenis. Hieruit blijkt dat de beide musea met een andere visie zijn begonnen aan hun restauraties, maar dat in beide gevallen de negentiende-eeuwse vorm niet teruggehaald kan worden zonder ook iets van het negentiende-eeuwse gedachtegoed te herstellen

Attachment in interaction:A conversation analytic study on dinner conversations with adolescents in family-style group care

Attachment in interaction: a conversation analytic study on dinner conversations with adolescents in family-style group careOut-of-home placed children or adolescents can be placed in family-style group care, a promising alternative youth care setting. It provides children and Professional Foster Parents (PFPs) with the opportunity to create a continuous relationship. This relationship, in turn, is an important factor in building and maintaining attachment. Scientific literature shows that sensitivity and responsivity are crucial interactional elements for building and maintaining an attachment relationship, but little knowledge is available on how those concepts are displayed in mundane interactions. Therefore this dissertation studies dinner conversations between experienced PFPs and adolescents in family-style group care to find out how sensitivity and responsivity unfold in these conversations. The data consist of 300 hours of video-recordings coming from six family-style group care settings. The method of Conversation Analysis was used to analyse the conversations in detail. On the basis of four studies a better understanding is gained into how the dyadic concepts sensitivity and responsivity are displayed in daily interactions between PFPs and adolescents in family-style group care. The analysis of these specific phenomena disclose the PFP-adolescent interaction from different perspectives: the verbal and non-verbal actions of both PFPs and adolescents and how PFPs and adolescents align. In short, this dissertation provides a detailed analysis of interaction and improves the understanding of the dyadic concepts sensitivity and responsivity. It reveals that adolescents are active participants in interactions and shows that PFPs are inventive in their conversations with the adolescents