109,563 research outputs found

    Convergence and generalization of a recursion equation for primes

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    The main result is a generalization of Keller's recursion equation for finding a prime number given the previous primes. We also examine the convergence of the limit in Keller's equation and the convergence of the limit in the general equation. The latter is dependent on the choice of L-function

    Heated element fluid flow sensor Patent

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    Heated element sensor for fluid flow detection in thermal conductive conduit with adaptive means to determine flow rate and directio

    Engaged Leadership: New Concept or Evolutionary in Nature?

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    Mr. Woods provides a critique and a book review of Clint Swindall‘s Engaged Leadership. His accolades relate primarily to Swindell‘s communication of connecting the dynamics of a work environment and the applications of engaged leadership in fable format. He decries, however, the author‘s missed opportunities to further associate engaged leadership to an established theory of management and to use polling data which attempts to ascertain any cost savings associated with engaged leadership

    Executive Privilege in the Federal Courts

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    Apoptosis is one type of programmed cell death, important during tissue development and to maintain the tissue homeostasis. Apoptosis comprises a complex network of internal signaling pathways, and an important part of this signaling network is the action of voltage‐gated ion channels. The aim of this thesis was to explore the role of ion channels and the role of intracellular metal ions during apoptosis in Xenopus laevis oocytes. The reasons for using these oocytes are that they are large, robust, easy to handle, and easy to study electrophysiologically. Apoptosis was induced either chemically by incubation of the oocytes in staurosporine (STS) or mechanically by centrifugation of the oocytes. Ion currents were measured by a two‐electrode voltage clamp technique, intracellular ion concentrations were measured either directly by in‐house developed K+‐selective microelectrodes or indirectly by the electrophysiological technique, and apoptosis was measured by caspase‐3 activation. Paper I describes that the intracellular K+ concentration was reduced by about 30 % during STS‐induced apoptosis. However, this reduction was prevented by excessive expression of exogenous ion channels. Despite the magnitude of the intracellular K+ concentration, either normal or reduced level, the oocytes displayed normal signs of apoptosis, suggesting that the intracellular K+ reduction was not required for the apoptotic process. Because the intracellular K+ concentration was not critical for apoptosis we searched for other ion fluxes by exploring the electrophysiological properties of X. laevis oocytes. Paper II, describes a non‐inactivating Na+ current activated at positive membrane voltages that was upregulated by a factor of five during STS‐induced apoptosis. By preventing influx of Na+, the apoptotic signaling network involving capsase‐3 was prevented. To molecularly identify this voltage‐gated Na channel, the X. tropicalis genome and conserved regions of the human SCNA genes were used as a map. Paper III, shows that the voltage‐gated Na channel corresponds to the SCN2A gene ortholog and that supression of this SCN2A ortholog using miRNA prevented cell death. In conclusion, this thesis work demonstrated that a voltage‐gated Na channel is critical for the apoptotic process in X. laevis oocytes by increasing the intracellular Na+ concentration
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