525,703 research outputs found

    User Participation in Value Creation

    Get PDF
    This article examines HM Treasury’s proposal to account for the active participation of users in value creation in certain digital platforms. The first key question is whether there is any reason to believe, as HM Treasury suggests, that users only meaningfully or actively contribute to value creation in the context of certain digital platforms. The article accordingly explores the factors HM Treasury sets out for the attribution of income to active user participation, including features such as network effects, multisided business models, and a lack of physical presence in the jurisdiction of the user. It concludes that if a user participation concept were adopted into international tax norms, it is unlikely to be limited to digital businesses or to the business models particularly highlighted in the proposal issued by HM Treasury. The analysis proceeds by considering the factors set out by HM Treasury for the attribution of income to active user participation in the context of pharmaceuticals and biologics, the financial sector, and the “internet of things”. For example, the article concludes that under HM Treasury’s user participation theory, returns from certain London-based financial intermediation businesses would need to be reallocated to other jurisdictions. Moreover, as the internet of things develops, one would expect the range of business affected by the active user participation concept to constantly expand

    Molecular basis of gap junctional communication in the CNS of the leech Hirudo medicinalis

    Get PDF
    Gap junctions are intercellular channels that allow the passage of ions and small molecules between cells. In the nervous system, gap junctions mediate electrical coupling between neurons. Despite sharing a common topology and similar physiology, two unrelated gap junction protein families exist in the animal kingdom. Vertebrate gap junctions are formed by members of the connexin family, whereas invertebrate gap junctions are composed of innexin proteins. Here we report the cloning of two innexins from the leech Hirudo medicinalis. These innexins show a differential expression in the leech CNS: Hm-inx1 is expressed by every neuron in the CNS but not in glia, whereas Hm-inx2 is expressed in glia but not neurons. Heterologous expression in the paired Xenopus oocyte system demonstrated that both innexins are able to form functional homotypic gap junctions. Hm-inx1 forms channels that are not strongly gated. In contrast, Hm-inx2 forms channels that are highly voltage-dependent; these channels demonstrate properties resembling those of a double rectifier. In addition, Hm-inx1 and Hm-inx2 are able to cooperate to form heterotypic gap junctions in Xenopus oocytes. The behavior of these channels is primarily that predicted from the properties of the constituent hemichannels but also demonstrates evidence of an interaction between the two. This work represents the first demonstration of a functional gap junction protein from a Lophotrochozoan animal and supports the hypothesis that connexin-based communication is restricted to the deuterostome clade