42 research outputs found

    Steep anomalous dispersion in coherently prepared Rb vapor

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    Steep dispersion of opposite signs in driven degenerate two-level atomic transitions have been predicted and observed on the D2 line of 87Rb in an optically thin vapor cell. The intensity dependence of the anomalous dispersion has been studied. The maximum observed value of anomalous dispersion [dn/dnu ~= -6x10^{-11}Hz^{-1}] corresponds to anegative group velocity V_g ~= -c/23000.Comment: 4 pages, 4 figure

    Development of Gene Expression Markers of Acute Heat-Light Stress in Reef-Building Corals of the Genus Porites

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    Coral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of bleaching risks among individual reef sites. Gene expression analysis based on quantitative PCR (qPCR) can be used as a diagnostic tool to determine coral condition in situ. We evaluated the expression of 13 candidate genes during heat-light stress in a common Caribbean coral Porites astreoides, and observed strong and consistent changes in gene expression in two independent experiments. Furthermore, we found that the apparent return to baseline expression levels during a recovery phase was rapid, despite visible signs of colony bleaching. We show that the response to acute heat-light stress in P. astreoides can be monitored by measuring the difference in expression of only two genes: Hsp16 and actin. We demonstrate that this assay discriminates between corals sampled from two field sites experiencing different temperatures. We also show that the assay is applicable to an Indo-Pacific congener, P. lobata, and therefore could potentially be used to diagnose acute heat-light stress on coral reefs worldwide

    A Parallel VLSI Architecture for 1-Gb/s, 2048-b, Rate-1/2 Turbo Gallager Code Decoder

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    This paper presents a 2048 bit, rate 1/2 soft decision decoder for a new class of codes known as Turbo Gallager Codes. The decoder can support up to 1 Gbit/s code rate and performs up to 48 decoding iteration ensuring at the same time high throughput and good coding gain. In order to evaluate the performance and the gate complexity of the decoder VLSI architecture, it has been synthesized in a 0.18 ÎĽm standard-cell CMOS technology

    Far infrared technology (FIT) therapy patches, protects from inflammation, oxidative stress and promotes cellular vitality

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    Background: It is known from the most recent literature that far-infrared (FIR) radiations promote a broad spectrum of therapeutic benefits for cells and tissues.Objective: To identify molecular mechanisms by which FIT patches. as a far infrared technology, protects against damage caused by inflammatory process and oxidative stress.Methods: Endothelial cells (HUVEC, Human Umbilical Vein Endothelial Cells) were used as in vitro experimen- tal model. HINEC were stimulated with a pro-inflammatory cytokine, TNF-alpha, or hydrogen peroxide (H2O2) to induce oxidative stress. As markers of inflammation were evaluated: VCAM1 (Vascular Cell Adhesion Molecule 1), ICAM1 (Intercellular Adhesion Molecule 1) and E-Selectin by Western Blot analysis. Oxidative stress was assessed by cytofluorimetric analysis. The experiments were performed on control cells (no patch) or in cells treated with the FIT infrared technology applied on the basis of the culture plate.Results: HUVEC stimulated with TNF-alpha and treated with FIT patches had significant reduction of the expression of VCAM1, ICAM1 and E-Selectin (p<0.05). HUVEC stimulated with H2O2 and treated with FIT patches were significantly protected from oxidative stress (p <0.01) when compared to control cells. We measured cell viability and proliferation in HUVEC and HEK-293 (Human embryonic kidney cells) cells by MTT assay. HEK-293 and HUVEC treated with FIT patches showed a significantly higher percentage of basal vitality compared to control cells (p<0.000I for HEK-293, p<0.05 for HUVEC).Conclusion: FIT therapy patches - infrared technology, through these protective mechanisms, could be used in all pathologies where an increase in inflammation, oxidative stress and degenerative state are present
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