Arterial and microvascular supply of cerebral hemispheres in the nude mouse revealed using corrosion casting and scanning electron microscopy

Morphological analyses of cerebral vascularization are not only important for the characterization of the anatomical and physiological relationships between vascular and nervous tissue, but also required to understand structural modifications that occur in many pathological conditions affecting the brain. The aim of this study was to generate a three-dimensional vascular map of the cerebral hemispheres in the nude mouse brain, a widely used animal model for studying tumour biology. We used the corrosion casting (CC) technique to isolate blood vessels from 30 nude mouse brains. All casts were analysed using scanning electron microscopy (SEM), which generated quantitative data regarding vessel length and diameter as well as inter-vascular and inter-branching distances. We identified three different topographical regions: (i) the cortical region, characterized by a superficial wide sheet of vessels giving rise to terminal perforant vessels that penetrate the grey matter; (ii) the inner part of the grey matter, in which dense capillary nets form many flake-like structures extending towards the grey-white matter boundary, where perforant vessels finally change direction and form a well-defined vascular sheet; and (iii) the white matter layer, characterized by a more disorganized vascular architecture. In this study, we demonstrate the accuracy of the CC-SEM method in revealing the 3D-topographical organization of the vascular network of the normal nude mouse brain. These baseline data will serve as a reference for future anatomical investigations of pathological alterations, such as tumour infiltrations, using the nude mouse model

The Adoption and Diffusion of Wearables

Part 1: Technology Adoption, Diffusion and Ubiquitous ComputingInternational audienceAlthough the sales of wearables are increasing in the last few years, it is still unknown how wearables are actually adopted and being used in everyday life by consumers. In this study, we try to identify the adoption and diffusion patterns of wearables by performing a sentiment analysis on 97 semi-structured interviews with wearables owners/users focused on relevance and requirements of and resources and resistance related to wearables. Based on this analysis we conclude that developers and manufacturers of wearables should make their devices more relevant, more reliable and easier to use. They should also address privacy issues and foster habit (using it all and every day) in order to speed up the adoption and diffusion of wearables. The theoretical contribution of this paper is that habit should be studied as a potential dependent variable for intention to use

Production of Manoalide and Its Analogues by the Sponge Luffariella variabilis Is Hardwired

The Great Barrier Reef sponge Luffariella variabilis (Poléjaeff 1884) produces a range of potent anti-inflammatory compounds as its major metabolites. These major metabolites—manoalide monoacetate, manoalide, luffariellin A and seco-manoalide—were monitored temporally and spatially to quantify the potential yield from wild harvest or aquaculture. Production of the major metabolites was hardwired at the population level with little variation in space and time over meters to tens of kilometers in the Palm Islands, Queensland, Australia. Manoalide monoacetate (35 to 70 mg g−1 dry weight of sponge) was consistently the most abundant compound followed by manoalide (15 to 20 mg g−1 dry weight). Luffariellin A and seco-manoalide were 10 to 70 times less abundant and varied between 0 and 3 mg g−1 dry weight. On a larger spatial scale, L. variabilis from Davies Reef and Magnetic Island contained the same rank order and yields of compounds as the Palm Islands, indicating a generality of pattern over at least 100 km. The “hardwiring” of metabolite production at the population level by L. variabilis was also reflected in the lack of any inductive effect on metabolite production. In addition, individually monitored sponges produced fixed ratios of the major metabolites over time (years). However, these ratios varied between individuals, with some individuals consistently producing high levels of manoalide and manoalide monoacetate, providing the potential for selection of high-yielding stocks