3,171 research outputs found

    Rare-earth doped transparent ceramics for spectral filtering and quantum information processing

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    Homogeneous linewidths below 10 kHz are reported for the first time in high-quality Eu3+ doped Y 2O3 transparent ceramics. This result is obtained on the 7F0→5D0 transition in Eu3+ doped Y 2O3 ceramics and corresponds to an improvement of nearly one order of magnitude compared to previously reported values in transparent ceramics. Furthermore, we observed spectral hole lifetimes of ∼15 min that are long enough to enable efficient optical pumping of the nuclear hyperfine levels. Additionally, different Eu3+ concentrations (up to 1.0%) were studied, resulting in an increase of up to a factor of three in the peak absorption coefficient. These results suggest that transparent ceramics can be useful in applications where narrow and deep spectral holes can be burned into highly absorbing lines, such as quantum information processing and spectral filteringThis work was supported by the ANR projects RAMACO (No. 12-BS08-0015-01) and DISCRYS (No. 14-CE26-0037-01), Idex No. ANR-10-IDEX-0001-02 PSL⋆, and Nano’K project RECTUS. C.W.T. and R.L.C. acknowledge support from National Science Foundation (NSF) Award Nos. CHE-1416454 and PHY-1415628 and M.O.R. and L.E.B. from Project No. MAT2013- 43301-R of the Spanish Ministry of Economy and Competitiveness (MINECO) and Comunidad Autónoma de Madrid under Grant No. S2013/MIT-274

    Cervicovaginal fluid and semen block the microbicidal activity of hydrogen peroxide produced by vaginal lactobacilli

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    BACKGROUND: H(2)O(2 )produced by vaginal lactobacilli is believed to protect against infection, and H(2)O(2)-producing lactobacilli inactivate pathogens in vitro in protein-free salt solution. However, cervicovaginal fluid (CVF) and semen have significant H(2)O(2)-blocking activity. METHODS: We measured the H(2)O(2 )concentration of CVF and the H(2)O(2)-blocking activity of CVF and semen using fluorescence and in vitro bacterial-exposure experiments. RESULTS: The mean H(2)O(2 )measured in fully aerobic CVF was 23 ± 5 μM; however, 50 μM H(2)O(2 )in salt solution showed no in vitro inactivation of HSV-2, Neisseria gonorrhoeae, Hemophilus ducreyii, or any of six BV-associated bacteria. CVF reduced 1 mM added H(2)O(2 )to an undetectable level, while semen reduced 10 mM added H(2)O(2 )to undetectable. Moreover, the addition of just 1% CVF supernatant abolished in vitro pathogen-inactivation by H(2)O(2)-producing lactobacilli. CONCLUSIONS: Given the H(2)O(2)-blocking activity of CVF and semen, it is implausible that H(2)O(2)-production by vaginal lactobacilli is a significant mechanism of protection in vivo

    Narrow inhomogeneous and homogeneous optical linewidths in a rare earth doped transparent ceramic

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    Inhomogeneous and homogeneous linewidth are reported in a Eu3+ doped transparent Y2O3 ceramic for the 7F 0-5D0 transition, using high-resolution coherent spectroscopy. The 8.7-GHz inhomogeneous linewidth is close to that of single crystals, as is the 59-kHz homogeneous linewidth at 3 K (T2 = 5.4 μs). The homogeneous linewidth exhibits a temperature dependence that is typical of a crystalline environment, and additional dephasing observed in the ceramic is attributed to magnetic impurities or defects introduced during the synthesis process. The absence of Eu3+segregation at the grain boundaries, evidenced through confocal microfluorescence, further indicates that the majority of Eu3+ions in the ceramic experience an environment comparable to a single crystal. The obtained results suggest that ceramic materials can be competitive with single crystals for applications in quantum information and spectral hole burning devices, beyond their current applications in lasers and scintillatorsThis work was supported by National Science Foundation under award No. PHY-1212462, the European Union FP7 project QuRep (247743), the Spanish Ministry of Economy and Competitiveness (MAT2010-17443) and Comunidad de Madrid (S-2009/MAT-1756

    The effects of pioglitazone, a PPARγ receptor agonist, on the abuse liability of oxycodone among nondependent opioid users

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    Aims: Activation of PPARγ by pioglitazone (PIO) has shown some efficacy in attenuating addictive-like responses in laboratory animals. The ability of PIO to alter the effects of opioids in humans has not been characterized in a controlled laboratory setting. The proposed investigation sought to examine the effects of PIO on the subjective, analgesic, physiological and cognitive effects of oxycodone (OXY). Methods: During this investigation, nondependent prescription opioid abusers (N = 17 completers) were maintained for 2-3 weeks on ascending daily doses of PIO (0 mg, 15 mg, 45 mg) prior to completing a laboratory session assessing the aforementioned effects of OXY [using a within-session cumulative dosing procedure (0, 10, and 20 mg, cumulative dose = 30 mg)]. Results: OXY produced typical mu opioid agonist effects: miosis, decreased pain perception, and decreased respiratory rate. OXY also produced dose-dependent increases in positive subjective responses. Yet, ratings such as: drug "liking," "high," and "good drug effect," were not significantly altered as a function of PIO maintenance dose. Discussion: These data suggest that PIO may not be useful for reducing the abuse liability of OXY. These data were obtained with a sample of nondependent opioid users and therefore may not be applicable to dependent populations or to other opioids. Although PIO failed to alter the abuse liability of OXY, the interaction between glia and opioid receptors is not well understood so the possibility remains that medications that interact with glia in other ways may show more promise

    Perchance to Dream: Art, Mathematics, and Shakespeare

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    Visual representation of textual works has often aided in the understanding of sophisticated concepts. In the Digital Age this is particularly true, given the advent of natural language processing, the ubiquity of general programming languages, and the maturation of digital visualization. In this article, we eschew the traditional disciplinary boundaries to view and analyze Shakespeare’s works in various ways. Our point of departure is Hamlet, where we first examine the play as a unity — both graphically and analytically. We then focus on Act III, Scene 1, where we analyze one of the most famous passages in English Literature: Hamlet’s famous “To be or not to be” soliloquy. We study this passage with a sequence of progressively sophisticated content analysis software packages, each of which renders a useful artistic visual representation of the text. In these studies, we have gathered preliminary sets of context-free content data which allow us to give illustrations of a wide range of analytic tools. Throughout our explorations, we use new modes of linguistic exploration, synthesized from elements of philosophy, literature, mathematics, computer science, psychology, and the arts. Many of the methods, which help to form these new modes of exploration, may appear individually as Cartesian in nature, yet when collectively synthesized into a holism, form a fundamentally phenomenological study of human creativity

    The Courts, the Public, and the Law Explosion

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    The Courts, the Public, and the Law Explosion

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