26 resultados para Altoviti, Bindo, 1491-1556.
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A polymeric metal-organic gel is described, which acts as a template in the preparation of macroporous polymethylmethacrylate, and can be easily removed post polymerisation.
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OBJECTIVE: To determine the effect of dietary supplementation with omega-3 fish oils with or without copper on disease activity in systemic lupus erythematosus (SLE). Fish oil supplementation has a beneficial effect on murine models of SLE, while exogenous copper can decrease the formation of lupus erythematosus cells in rats with a hydralazine-induced collagen disease. METHODS: A double blind, double placebo controlled factorial trial was performed on 52 patients with SLE. Patients were randomly assigned to 4 treatment groups. Physiological doses of omega-3 fish oils and copper readily obtainable by dietary means were used. One group received 3 g MaxEPA and 3 mg copper, another 3 g MaxEPA and placebo copper, another 3 mg copper and placebo fish oil, and the fourth group received both placebo capsules. Serial measurements of disease activity using the revised Systemic Lupus Activity Measure (SLAM-R) and peripheral blood samples for routine hematological, biochemical, and immunological indices were taken at baseline, 6, 12, and 24 weeks. RESULTS: There was a significant decline in SLAM-R score from 6.12 to 4.69 (p <0.05) in those subjects taking fish oil compared to placebo. No significant effect on SLAM-R was observed in subjects taking copper. Laboratory variables were unaffected by either intervention. CONCLUSION: In the management of SLE, dietary supplementation with fish oil may be beneficial in modifying symptomatic disease activity.
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In this theoretical paper, the analysis of the effect that ON-state active-device resistance has on the performance of a Class-E tuned power amplifier using a shunt inductor topology is presented. The work is focused on the relatively unexplored area of design facilitation of Class-E tuned amplifiers where intrinsically low-output-capacitance monolithic microwave integrated circuit switching devices such as pseudomorphic high electron mobility transistors are used. In the paper, the switching voltage and current waveforms in the presence of ON-resistance are analyzed in order to provide insight into circuit properties such as RF output power, drain efficiency, and power-output capability. For a given amplifier specification, a design procedure is illustrated whereby it is possible to compute optimal circuit component values which account for prescribed switch resistance loss. Furthermore, insight into how ON-resistance affects transistor selection in terms of peak switch voltage and current requirements is described. Finally, a design example is given in order to validate the theoretical analysis against numerical simulation.
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2,5,-Dimethoxy-4-bromoamphetamine (DOB) is of particular interest among the various
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3-Phosphoinositide-dependent protein kinase-1 (PDK1) appears to play a central regulatory role in many cell signalings between phosphoinositide-3 kinase and various intracellular serine/threonine kinases. In resting cells, PDK1 is known to be constitutively active and is further activated by tyrosine phosphorylation (Tyr(9) and Tyr(373/376)) following the treatment of the cell with insulin or pervanadate. However, little is known about the mechanisms for this additional activation of PDK1. Here, we report that the SH2 domain of Src, Crk, and GAP recognized tyrosine-phosphorylated PDK1 in vitro. Destabilization of PDK1 induced by geldanamycin (a Hsp90 inhibitor) was partially blocked in HEK 293 cells expressing PDK1- Y9F. Co-expression of Hsp90 enhanced PDK1-Src complex formation and led to further increased PDK1 activity toward PKB and SGK. Immunohistochemical analysis with anti- phospho-Tyr9 antibodies showed that the level of Tyr9 phosphorylation was markedly increased in tumor samples compared with normal. Taken together, these data suggest that phosphorylation of PDK1 on Tyr9, distinct from Tyr373/376, is important for PDK1/Src complex formation, leading to PDK1 activation. Furthermore, Tyr9 phosphorylation is critical for the stabilization of both PDK1 and the PDK1/Src complex via Hsp90-mediated protection of PDK1 degradation.
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Differential gene expression in two established initiation and promotion skin carcinogenesis models during promotion and tumor formation was determined by microarray technology with the purpose of distinguishing the genes more associated with neoplastic transformation from those linked with proliferation and differentiation. The first model utilized dimethylbenz[a]anthracene initiation and 12-O-tetradecanoylphorbol 13-acetate (TPA) promotion in the FVB/N mouse, and the second TPA promotion of the Tg.Ac mouse, which is endogenously initiated by virtue of an activated Ha-ras transgene. Comparison of gene expression profiles across the two models identified genes whose altered expression was associated with papilloma formation rather than TPA-induced proliferation and differentiation. DMBA suppressed TPA-induced differentiation which allowed identification of those genes associated more specifically with differentiation rather than proliferation. EASE (Expression Analysis Systemic Explorer) indicated a correlation between muscle-associated genes and skin differentiation, whereas genes involved with protein biosynthesis were strongly correlated with proliferation. For verification the altered expression of selected genes were confirmed by RT-PCR; Carbonic anhydrase 2, Thioredoxin 1 and Glutathione S-transferase omega 1 associated with papilloma formation and Enolase 3, Cystatin 6 and Filaggrin associated with TPA-induced proliferation and differentiation. In situ analysis located the papillomas Glutathione S-transferase omega 1 expression to the proliferating areas of the papillomas. Thus we have identified profiles of differential gene expression associated with the tumorigenesis and promotion stages for skin carcinogenesis in the mouse.
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1. We collated information from the literature on life history traits of the roach (a generalist freshwater fish), and analysed variation in absolute fecundity, von Bertalanffy parameters, and reproductive lifespan in relation to latitude, using both linear and non-linear regression models. We hypothesized that because most life history traits are dependent on growth rate, and growth rate is non-linearly related with temperature, it was likely that when analysed over the whole distribution range of roach, variation in key life history traits would show non-linear patterns with latitude.
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.The design of a 6T SRAM cell with 20 nm junctionless (JL) MOSFETs is reported. It is shown that a 6T SRAM cell designed with JL MOSFETs achieves a high static noise margin (SNM) of 185 mV, retention noise or hold margin (RNM) of 381 mV and writability current (IWR) of 33 mA along with a low leakage current of 2 pA at a supply voltage (VDD) of 0.9 V for cell and pullup ratios of 1. Results offer a new opportunity to design future SRAM cells with nanoscale JL MOSFETs.
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Flow maldistribution of the exhaust gas entering a Diesel Particulate Filter (DPF) can cause uneven soot distribution during loading and excessive temperature gradients during the regeneration phase. Minimising the magnitude of this maldistribution is therefore an important consideration in the design of the inlet pipe and diffuser, particularly in situations where packaging constraints dictate bends in the inlet pipe close to the filter, or a sharp diffuser angle. This paper describes the use of Particle Image Velocimetry (PIV) to validate a Computational Fluid Dynamic (CFD) model of the flow within the inlet diffuser of a DPF so that CFD can be used with confidence as a tool to minimise this flow maldistribution. PIV is used to study the flow of gas into a DPF over a range of steady state flow conditions. The distribution of flow approaching the front face of the substrate was of particular interest to this study. Optically clear diffusing cones were designed and placed between pipe and substrate to allow PIV analysis to take place. Stereoscopic PIV was used to eliminate any error produced by the optical aberrations caused by looking through the curved wall of the inlet cone. In parallel to the experiments, numerical analysis was carried out using a CFD program with an incorporated DPF model. Boundary conditions for the CFD simulations were taken from the experimental data, allowing an experimental validation of the numerical results. The CFD model incorporated a DPF model, the cement layers seen in segmented filters and the intumescent matting that is commonly used to pack the filter into a metal casing. The mesh contained approximately 580,000 cells and used the realizable ?-e turbulence model. The CFD simulation predicted both pressure drop across the DPF and the velocity field within the cone and at the DPF face with reasonable accuracy, providing confidence in the use the CFD in future work to design new, more efficient cones.