Entwicklungslinien und Perspektiven der New Urban Tourism-Forschung

Stadttourismus und städtischer Alltag prägen einander vielfältig, bisweilen auf regelrecht konstitutive Art und Weise. Es scheint offensichtlich, dass Tourismus im Alltag einer Stadtbevölkerung in vielerlei Form präsent werden kann. Gleichwohl hält sich die tradierte Vorstellung von Stadt als Destination, welche einerseits von Bewohner*innen bewohnt und andererseits von Besucher*innen besucht wird. Daher gilt es nach wie vor zu versuchen, (Stadt-)Tourismus weniger isoliert und stärker als integriertes Momentum des Städtischen zu denken. Der vorliegende Beitrag widmet sich dieser engen Verflechtung von Stadt und Tourismus und zielt darauf, ihre vielfältigen Wechselwirkungen analytisch zu fassen. Dazu werden zunächst vier empirische Beobachtungen aufgespannt, die den Kontext der New Urban Tourism-Forschung thesenartig illustrieren. Daran anschließend erfolgt ein Abriss konzeptioneller Anknüpfungspunkte, welche die New Urban Tourism-Forschung informieren. Diese theoretischen Bezüge bilden gleichzeitig die Grundlage für die folgenden drei analytischen Dimensionen, die wir als Vorschläge zur Systematisierung der Forschungsstrecke verstehen: (1) Faszination für das Alltägliche, (2) Begegnungen und Erschließung neuer Orte des Zusammentreffens und (3) Ko-Produktion des Städtischen. Der Beitrag schließt mit einer kritischen Reflexion der Grenzen der aktuellen New Urban Tourism-Forschung sowie mit einigen Überlegungen zu zukünftigen Arbeitsfeldern

Lypd6 Enhances Wnt/β-Catenin Signaling by Promoting Lrp6 Phosphorylation in Raft Plasma Membrane Domains

Wnt/beta-catenin signaling plays critical roles during embryogenesis, tissue homeostasis, and regeneration. How Wnt-receptor complex activity is regulated is not yet fully understood. Here, we identify the Ly6 family protein LY6/PLAUR domain-containing 6 (Lypd6) as a positive feedback regulator of Wnt/beta-catenin signaling. lypd6 enhances Wnt signaling in zebrafish and Xenopus embryos and in mammalian cells, and it is required for wnt8-mediated patterning of the mesoderm and neuroectoderm during zebrafish gastrulation. Lypd6 is GPI anchored to the plasma membrane and physically interacts with the Wnt receptor Frizzled8 and the coreceptor Lrp6. Biophysical and biochemical evidence indicates that Lypd6 preferentially localizes to raft membrane domains, where Lrp6 is phosphorylated upon Wnt stimulation. lypd6 knockdown or mislocalization of the Lypd6 protein to nonraft membrane domains shifts Lrp6 phosphorylation to these domains and inhibits Wnt signaling. Thus, Lypd6 appears to control Lrp6 activation specifically in membrane rafts, which is essential for downstream signaling.The GenBank accession number for the partial Xenopus laevis lypd6 complementary DNA reported in this paper is KF042353

A fully automated high-throughput workflow for 3D-based chemical screening in human midbrain organoids

Three-dimensional (3D) culture systems have fueled hopes to bring about the next generation of more physiologically relevant high-throughput screens (HTS). However, current protocols yield either complex but highly heterogeneous aggregates ('organoids') or 3D structures with less physiological relevance ('spheroids'). Here, we present a scalable, HTS-compatible workflow for the automated generation, maintenance, and optical analysis of human midbrain organoids in standard 96-well-plates. The resulting organoids possess a highly homogeneous morphology, size, global gene expression, cellular composition, and structure. They present significant features of the human midbrain and display spontaneous aggregate-wide synchronized neural activity. By automating the entire workflow from generation to analysis, we enhance the intra- and inter-batch reproducibility as demonstrated via RNA sequencing and quantitative whole mount high-content imaging. This allows assessing drug effects at the single-cell level within a complex 3D cell environment in a fully automated HTS workflow

Dynamic association with donor cell filopodia and lipid-modification are essential features of Wnt8a during patterning of the zebrafish neuroectoderm

BACKGROUND: Wnt proteins are conserved signaling molecules that regulate pattern formation during animal development. Many Wnt proteins are post-translationally modified by addition of lipid adducts. Wnt8a provides a crucial signal for patterning the anteroposterior axis of the developing neural plate in vertebrates. However, it is not clear how this protein propagates from its source, the blastoderm margin, to the target cells in the prospective neural plate, and how lipid-modifications might influence Wnt8a propagation and activity. RESULTS: We have dynamically imaged biologically active, fluorescently tagged Wnt8a in living zebrafish embryos. We find that Wnt8a localizes to membrane-associated, punctate structures in live tissue. In Wnt8a expressing cells, these puncta are found on filopodial cellular processes, from where the protein can be released. In addition, Wnt8a is found colocalized with Frizzled receptor-containing clusters on signal receiving cells. Combining in vitro and in vivo assays, we compare the roles of conserved Wnt8a residues in cell and non-cell-autonomous signaling activity and secretion. Non-signaling Wnt8 variants show these residues can regulate Wnt8a distribution in producing cell membranes and filopodia as well as in the receiving tissue. CONCLUSIONS: Together, our results show that Wnt8a forms dynamic clusters found on filopodial donor cell and on signal receiving cell membranes. Moreover, they demonstrate a differential requirement of conserved residues in Wnt8a protein for distribution in producing cells and receiving tissue and signaling activity during neuroectoderm patterning

Author response

Despite the critical role of endothelial Wnt/β-catenin signaling during central nervous system (CNS) vascularization, how endothelial cells sense and respond to specific Wnt ligands and what aspects of the multistep process of intra-cerebral blood vessel morphogenesis are controlled by these angiogenic signals remain poorly understood. We addressed these questions at single-cell resolution in zebrafish embryos. We identify the GPI-anchored MMP inhibitor Reck and the adhesion GPCR Gpr124 as integral components of a Wnt7a/Wnt7b-specific signaling complex required for brain angiogenesis and dorsal root ganglia neurogenesis. We further show that this atypical Wnt/ β-catenin signaling pathway selectively controls endothelial tip cell function and hence, that mosaic restoration of single wild-type tip cells in Wnt/β-catenin-deficient perineural vessels is sufficient to initiate the formation of CNS vessels. Our results identify molecular determinants of ligand specificity of Wnt/β-catenin signaling and provide evidence for organ-specific control of vascular invasion through tight modulation of tip cell function.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Mobility in a Globalised World 2016

The term mobility has different meanings in the following science disciplines. In economics, mobility is the ability of an individual or a group to improve their economic status in relation to income and wealth within their lifetime or between generations. In information systems and computer science, mobility is used for the concept of mobile computing, in which a computer is transported by a person during normal use. Logistics creates by the design of logistics networks the infrastructure for the mobility of people and goods. Electric mobility is one of today’s solutions from engineering perspective to reduce the need of energy resources and environmental impact. Moreover, for urban planning, mobility is the crunch question about how to optimise the different needs for mobility and how to link different transportation systems. In this publication we collected the ideas of practitioners, researchers, and government officials regarding the different modes of mobility in a globalised world, focusing on both domestic and international issues

Wnt signaling controls pro-regenerative Collagen XII in functional spinal cord regeneration in zebrafish

The inhibitory extracellular matrix in a spinal lesion site is a major impediment to axonal regeneration in mammals. In contrast, the extracellular matrix in zebrafish allows substantial axon re-growth, leading to recovery of movement. However, little is known about regulation and composition of the growth-promoting extracellular matrix. Here we demonstrate that activity of the Wnt/beta-catenin pathway in fibroblast-like cells in the lesion site is pivotal for axon re-growth and functional recovery. Wnt/beta-catenin signaling induces expression of col12a1a/b and deposition of Collagen XII, which is necessary for axons to actively navigate the non-neural lesion site environment. Overexpression of col12a1a rescues the effects of Wnt/beta-catenin pathway inhibition and is sufficient to accelerate regeneration. We demonstrate that in a vertebrate of high regenerative capacity, Wnt/beta-catenin signaling controls the composition of the lesion site extracellular matrix and we identify Collagen XII as a promoter of axonal regeneration. These findings imply that the Wnt/beta-catenin pathway and Collagen XII may be targets for extracellular matrix manipulations in non-regenerating species

Remigration Nador II: Der tertiaere Sektor im laendlichen Raum der Provinz Nador (Marokko) unter dem Einfluss der Arbeitsmigration: 14 Tabellen

SIGLEAvailable from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel C 196315 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Key factors for successful leisure and tourism public transport provision

In the second half of the 20th century, the main focus of transport policy and transport studies was on the reduction of the use of motorised, individual transport, in particular with regard to daily commuter traffic. The main concepts concentrated on creating an attractive public transport supply and, where possible, improving the infrastructure for non-motorized traffic in order to open up alternative forms of travel. Although these concepts produced noticeable effects on everyday travel, they could not cope with steadily rising problems in the field of leisure traffic. Therefore, primarily supply oriented, autocratic desktop transport policies cannot be seen as a promising approach within the leisure context. Consequently, the article focuses on the necessary key factors for successful leisure and tourism public transport provision. It stresses the need for rethinking transport policy by choosing a demand oriented approach and realising the importance of additional accompanying efforts in the areas of marketing, transparency and quality. Focusing on the demand side, with its individual attitudes and preferences, leads to a new understanding of traffic planning by adopting a bottom up, rather than a top down approach