993 resultados para voltage-ride through
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Two forms of the activated beta(1)-adrenoceptor exist, one that is stabilized by (-)-noradrenaline and is sensitive to blockade by (-)-propranolol and another which is stabilized by partial agonists such as (-)-pindolol and (-)-CGP 12177 but is relatively insensitive to (-)-propranolol. We investigated the effects of stimulation of the propranolol-resistant PI-adrenoceptor in the human heart. Myocardium from non-failing and failing human hearts were set up to contract at 1 Hz. In right atrium from non-ailing hearts in the presence of 200 nM (-)-propranolol, (-)-CGP 12177 caused concentration-dependent increases in contractile force (-logEC(50)[M] 7.3+/-0.1, E-max 23+/-1% relative to maximal (-)-isoprenaline stimulation of beta(1)- and beta(2)-adrenoceptors, n=86 patients), shortening of the time to reach peak force (-logEC(50)[M] 7.4+/-0.1, E-max 37+/-5%, n=61 patients) and shortening of the time to reach 50% relaxation (t(50%), -logEC(50)[M] 7.3+/-0.1, E-max 33+/-2%, n=61 patients). The potency and maxima of the positive inotropic effects were independent of Ser49Gly- and Gly389Arg-beta(1)-adrenoceptor polymorphisms but were potentiated by the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (-logEC(50)[M] 7.7+/-0.1, E-max 68+/-6%, n=6 patients, P
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Objective To investigate the effect of lipophilicity on the percutaneous penetration of a homologous series of alcohols through canine skin Design Skin harvested from Greyhound thorax was placed in Franz-type diffusion cells and the in vitro passage of radio-labelled (C-14) alcohols (ethanol, butanol, hexanol and octanol (Log P 0.19 - 3.0)) through separate skin sections was measured in replicates of five. Permeability coefficient (k(P), cm/h), maximum flux (J(max), mol/cm(2)/h) and residue remaining within the skin were determined. Results The k(P) increased with increasing lipophilicity (6.2 x 10(-4) +/- 1.6 x 10(-4) cm/h for ethanol to 1.8 x 10(-2) 3.6 x 10(-3) cm/h for octanol). Alcohol residues remaining within each skin sample followed a similar pattern. An exponential decrease in Jmax with increasing lipophilicity was observed. Conclusion Changes in canine skin permeability occur with increasing alcohol lipophilicity. This finding has practical consequences for the design of topical formulations and optimisation of drug delivery through animal skin.
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The purpose of this study was to examine the development of six leader-athletes. In-depth qualitative interviews were used to explore the various activities that leader athletes engaged in from an early age as well as the roles and influences that peers, coaches, and parents played within these activities. Results indicated that leadership development in sport focused on developing four central components: high skill, strong work ethic, enriched cognitive sport knowledge, and good rapport with people. The types of activities engaged in throughout development as well as receiving feedback, acknowledgement, support, cognitive engagement, mature conversations with adults, and physical encounters with older peers are important social influences that can play an instrumental role in the formation of these four central tenets.
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In this report, we investigate the role of the RNA-binding protein HuR during skeletal myogenesis. At the onset of myogenesis in differentiating C2C12 myocytes and in vivo in regenerating mouse muscle, HuR cytoplasmic abundance increased dramatically, returning to a predominantly nuclear presence upon completion of myogenesis. mRNAs encoding key regulators of myogenesis-specific transcription (myogenin and MyoD) and cell cycle withdrawal (p21), bearing AU-rich regions, were found to be targets of HuR in a differentiation-dependent manner. Accordingly, mRNA half-lives were highest during differentiation, declining when differentiation was completed. Importantly, HuR-overexpressing C2C12 cells displayed increased target mRNA expression and half-life and underwent precocious differentiation. Our findings underscore a critical function for HuR during skeletal myogenesis linked to HuR's coordinate regulation of muscle differentiation genes.
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Utiliza-se o método coordenada geradora Hartree-Fock para gerar bases Gaussianas adaptadas para os átomos de Li (Z=3) até Xe (Z=54). Neste método, integram-se as equações de Griffin-Hill-Wheeler-Hartree-Fock através da técnica de discretização integral. Comparam-se as funções de ondas geradas neste trabalho com as funções de ondas Roothaan-Hartree-Fock de Clementi e Roetti (1974) e com outros conjuntos de bases relatados na literatura. Para os átomos estudados aqui, os erros em nossas energias totais relativos aos limites numéricos Hartree-Fock são sempre menores que 7,426 milihartree.
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Poly(vinylidene fluoride-trifluoethylene) electrospun membranes were obtained from a blend of dimethylformamide (DMF) and methylethylketone (MEK) solvents. The inclusion of the MEK to the solvent system promotes a faster solvent evaporation allowing complete polymer crystallization during the jet travelling between the tip and the grounded collector. Several processing parameters were systematically changed to study their influence on fiber dimensions. Applied voltage and inner needle diameter do not have large influence on the electrospun fiber average diameter but in the fiber diameter distribution. On the other hand, the increase of the distance between the needle tip to collector results in fibers with larger average diameter. Independently on the processing conditions, all mats are produced in the electroactive phase of the polymer. Further, MC-3T3-E1cell adhesion was not inhibited by the fiber mats preparation, indicating their potential use for biomedical applications.
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By identifying energy waste streams in vehicles fuel consumption and introducing the concept of lean driving systems, a technological gap for reducing fuel consumption was identified. This paper proposes a solution to overcome this gap, through a modular vehicle architecture aligned with driving patterns. It does not address detailed technological solutions; instead it models the potential effects in fuel consumption through a modular concept of a vehicle and quantifies their dependence on vehicle design parameters (manifesting as the vehicle mass) and user behavior parameters (driving patterns manifesting as the use of a modular car in lighter and heavier mode, in urban and highway cycles). Modularity has been functionally applied in automotive industry as manufacture and assembly management strategies; here it is thought as a product development strategy for flexibility in use, driven by environmental concerns and enabled by social behaviors. The authors argue this concept is a step forward in combining technological solutions and social behavior, of which eco-driving is a vivid example, and potentially evolutionary to a lean, more sustainable, driving culture.
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Many organisations need to extract useful information from huge amounts of movement data. One example is found in maritime transportation, where the automated identification of a diverse range of traffic routes is a key management issue for improving the maintenance of ports and ocean routes, and accelerating ship traffic. This paper addresses, in a first stage, the research challenge of developing an approach for the automated identification of traffic routes based on clustering motion vectors rather than reconstructed trajectories. The immediate benefit of the proposed approach is to avoid the reconstruction of trajectories in terms of their geometric shape of the path, their position in space, their life span, and changes of speed, direction and other attributes over time. For clustering the moving objects, an adapted version of the Shared Nearest Neighbour algorithm is used. The motion vectors, with a position and a direction, are analysed in order to identify clusters of vectors that are moving towards the same direction. These clusters represent traffic routes and the preliminary results have shown to be promising for the automated identification of traffic routes with different shapes and densities, as well as for handling noise data.
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This paper reports on the development of specific slicing techniques for functional programs and their use for the identification of possible coherent components from monolithic code. An associated tool is also introduced. This piece of research is part of a broader project on program understanding and re-engineering of legacy code supported by formal methods