941 resultados para HARD TICK


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Unprecedented basin-scale ecological changes are occurring in our seas. As temperature and carbon dioxide concentrations increase, the extent of sea ice is decreasing, stratification and nutrient regimes are changing, and pH is decreasing. These unparalleled changes present new challenges for managing our seas as we are only just beginning to understand the ecological manifestations of these climate alterations. The Marine Strategy Framework Directive requires all European Member States to achieve Good Environmental Status (GES) in their seas by 2020; this means management toward GES will take place against a background of climate-driven macroecological change. Each Member State must set environmental targets to achieve GES; however, in order to do so an understanding of large-scale ecological change in the marine ecosystem is necessary. Much of our knowledge of macroecological change in the North Atlantic is a result of research using data gathered by the Continuous Plankton Recorder (CPR) survey, a near-surface plankton monitoring program which has been sampling in the North Atlantic since 1931. CPR data indicate that North Atlantic and North Sea plankton dynamics are responding to both climate and human-induced changes, presenting challenges to the development of pelagic targets for achievement of GES in European seas. Thus the continuation of long-term ecological time-series such as the CPR is crucial for informing and supporting the sustainable management of European seas through policy mechanisms.

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We report on the successful fabrication of arrays of switchable nanocapacitors made by harnessing the self-assembly of materials. The structures are composed of arrays of 20-40 nm diameter Pt nanowires, spaced 50-100 nm apart, electrodeposited through nanoporous alumina onto a thin film lower electrode on a silicon wafer. A thin film ferroelectric (both barium titanate (BTO) and lead zirconium titanate (PZT)) has been deposited on top of the nanowire array, followed by the deposition of thin film upper electrodes. The PZT nanocapacitors exhibit hysteresis loops with substantial remnant polarizations, while although the switching performance was inferior, the low-field characteristics of the BTO nanocapacitors show dielectric behavior comparable to conventional thin film heterostructures. While registration is not sufficient for commercial RAM production, this is nevertheless an embryonic form of the highest density hard-wired FRAM capacitor array reported to date and compares favorably with atomic force microscopy read-write densities.

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It is ten years since the publication of three papers describing the cloning of a new proto-oncogene serine/threonine kinase termed protein kinase B (PKB)/Akt. Key roles for this protein kinase in cellular processes such as glucose metabolism, cell proliferation, apoptosis, transcription and cell migration are now well established. The explosion of publications involving PKB/Akt in the past three years emphasizes the high level of current interest in this signalling molecule. This review focuses on tracing the characterization of this kinase, through the elucidation of its mechanism of regulation, to its role in regulating physiological and pathophysiological processes,to our current understanding of the biology of PKB/Akt, and prospects for the future.

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Although Sloutsky agrees with our interpretation of our data, he argues that the totality of the evidence supports his claim that children make inductive generalisations on the basis of similarity. Here we take issue with his characterisation of the alternative hypotheses in his informal analysis of the data, and suggest that a thorough Bayesian analysis, although practically very difficult, is likely to result in a more finely balanced outcome than he suggests. (c) 2008 Elsevier B.V. All rights reserved.

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Suppressors of cytokine signaling (SOCS) proteins are a family of proteins that are able to act in a classic negative feedback loop to regulate cytokine signal transduction. The regulation of the immune response by SOCS proteins may contribute to persistent infection or even a fatal outcome. In this study, we have investigated the induction of SOCS 1-3 after peripheral infection with West Nile virus (WNV) or tick-borne encephalitis virus (TBEV) in the murine model. We have shown that the cytokine response after infection of mice with WNV or TBEV induces an upregulation in the brain of mRNA transcripts for SOCS 1 and SOCS 3, but not SOCS 2. We hypothesize that SOCS proteins may play a role in limiting cytokine responses in the brain as a neuroprotective mechanism, which may actually enhance the ability of neuroinvasive viruses such as WNV and TBEV to spread and cause disease.