The neural crest (NC) is a major contributor to the vertebrate craniofacial skeleton, detailed in model organisms through embryological and genetic approaches, most notably in chick and mouse. Despite many similarities between these rather distant species, there are also distinct differences in the contribution of the NC, particularly to the calvariae of the skull. Lack of information about other vertebrate groups precludes an understanding of the evolutionary significance of these differences. Study of zebrafish craniofacial development has contributed substantially to understanding of cartilage and bone formation in teleosts, but there is currently little information on NC contribution to the zebrafish skeleton. Here, we employ a two–transgene system based on Cre recombinase to genetically label NC in the zebrafish. We demonstrate NC contribution to cells in the cranial ganglia and peripheral nervous system known to be NC–derived, as well as to a subset of myocardial cells. The indelible labeling also enables us to determine NC contribution to late–forming bones, including the calvariae. We confirm suspected NC origin of cartilage and bones of the viscerocranium, including cartilages such as the hyosymplectic and its replacement bones (hymandibula and symplectic) and membranous bones such as the opercle. The cleithrum develops at the border of NC and mesoderm, and as an ancestral component of the pectoral girdle was predicted to be a hybrid bone composed of both NC and mesoderm tissues. However, we find no evidence of a NC contribution to the cleithrum. Similarly, in the vault of the skull, the parietal bones and the caudal portion of the frontal bones show no evidence of NC contribution. We also determine a NC origin for caudal fin lepidotrichia; the presumption is that these are derived from trunk NC, demonstrating that these cells have the ability to form bone during normal vertebrate development.

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This paper considers how online, distance students enact the space of 'the university', in the context of the rise of distance education within a traditional, 'elite' institution. Aiming to provide insight into how students translate into distance the space of a university which has traditionally had its basis in conventional on-campus education, it locates itself within the 'new mobilities' paradigm (Urry 2007), drawing on four different kinds of social space delineated by Mol and Law (1994, 2001) in order to analyse narrative and visual data generated with distance students at the University of Edinburgh. The paper shows that the material campus continues to be symbolically and materially significant for a group of students who may never physically attend that campus. Distance students, we find, need their own version of the 'spatial certainties' of bounded, campus space. Yet, in exploring the 'new proximities' of online distance education, we also argue that to define institutional and academic authenticity solely in terms of this bounded, 'regional' space is inadequate in the face of the other topologies which also come into play throughout distance students' accounts of what it means to be 'at' university.

<p>In this paper, we look at how the massive open online course (MOOC) format developed by connectivist researchers and enthusiasts can help analyze the complexity, emergence, and chaos at work in the field of education today. We do this through the prism of a MobiMOOC, a six-week course focusing on mLearning that ran from April to May 2011. MobiMOOC embraced the core MOOC components of self-organization, connectedness, openness, complexity, and the resulting chaos, and, as such, serves as an interesting paradigm for new educational orders that are currently emerging in the field. We discuss the nature of participation in MobiMOOC, the use of mobile technology and social media, and how these factors contributed to a chaotic learning environment with emerging phenomena. These emerging phenomena resulted in a transformative educational paradigm. <br /><br /></p>

In this paper, the authors suggest the merger of the Massively Open Online Course (MOOC) format and mobile learning (mLearning) based on mutual affordances of both contemporary learning/teaching formats to investigate learner interactions and dialogues in an open online course. The paper presents a case study of how MobiMOOC, a course created using the MOOC format, demonstrates the synergistic characteristics between the MOOC format and mLearning, making a combination of both fields ideal for contemporary, digital, collaborative learning, and knowledge construction based on learner interactions and dialogue. MobiMOOC was a six-week online course focusing on mLearning that ran in April and May 2011. An end-of-course survey provides insight that supports the synergies between MOOCs and mLearning: collaboration, informal and lifelong learning, and dialogue.