5,744 research outputs found

    Antiviral treatment alters the frequency of activating and inhibitory receptor-expressing natural killer cells in chronic Hepatitis B virus infected patients

    Get PDF
    Natural killer (NK) cells play a critical role in innate antiviral immunity, but little is known about the impact of antiviral therapy on the frequency of NK cell subsets. To this aim, we performed this longitudinal study to examine the dynamic changes of the frequency of different subsets of NK cells in CHB patients after initiation of tenofovir or adefovir therapy. We found that NK cell numbers and subset distribution differ between CHB patients and normal subjects; furthermore, the association was found between ALT level and CD158b+ NK cell in HBV patients. In tenofovir group, the frequency of NK cells increased during the treatment accompanied by downregulated expression of NKG2A and KIR2DL3. In adefovir group, NK cell numbers did not differ during the treatment, but also accompanied by downregulated expression of NKG2A and KIR2DL3. Our results demonstrate that treatment with tenofovir leads to viral load reduction, and correlated with NK cell frequencies in peripheral blood of chronic hepatitis B virus infection. In addition, treatments with both tenofovir and adefovir in chronic HBV infected patients induce a decrease of the frequency of inhibitory receptor+ NK cells, which may account for the partial restoration of the function of NK cells in peripheral blood following treatment

    Thorium-doping induced superconductivity up to 56 K in Gd1-xThxFeAsO

    Get PDF
    Following the discovery of superconductivity in an iron-based arsenide LaO1-xFxFeAs with a superconducting transition temperature (Tc) of 26 K[1], Tc was pushed up surprisingly to above 40 K by either applying pressure[2] or replacing La with Sm[3], Ce[4], Nd[5] and Pr[6]. The maximum Tc has climbed to 55 K, observed in SmO1-xFxFeAs[7, 8] and SmFeAsO1-x[9]. The value of Tc was found to increase with decreasing lattice parameters in LnFeAsO1-xFx (Ln stands for the lanthanide elements) at an apparently optimal doping level. However, the F- doping in GdFeAsO is particularly difficult[10,11] due to the lattice mismatch between the Gd2O2 layers and Fe2As2 layers. Here we report observation of superconductivity with Tc as high as 56 K by the Th4+ substitution for Gd3+ in GdFeAsO. The incorporation of relatively large Th4+ ions relaxes the lattice mismatch, hence induces the high temperature superconductivity.Comment: 4 pages, 3 figure

    Eye acupuncture for pain conditions: a scoping review of clinical studies.

    Get PDF
    Chinese eye acupuncture, focuses on treating different diseases by applying needle stimulation around the orbit of the eye. Since 1970, it has been used in China for the management of pain-related disorders. This scoping review systematically collected clinical studies on the use of eye acupuncture to treat pain conditions and identify any adverse events. Six databases including PubMed, the Cochrane Library, CNKI, VIP, Wan Fang Data and SinoMed were searched from 1970 to March 2019. Randomized controlled trials (RCTs), clinical controlled trials (CCTs) and case series on eye-acupuncture for pain conditions meeting the inclusion criteria were identified. Data were extracted on patients, interventions, details of eye acupuncture, control treatments and outcomes. Searches identified 81 clinical studies and a trend demonstrating an increasing number of published studies. All studies were conducted in China and published in Chinese. These included, 45 (55.6%) RCTs, 5 (6.2%) CCTs, and 31 (38.3%) case series, treating 7113 patients with 44 different pain-related diseases or symptoms. The most frequently reported conditions were headache (18, 16.2%), acute lumbar pain (7, 6.3%) and lumbar disc herniation (7, 6.3%). Treatment using small needles (φ0.25 × 13 mm), retained ≤30 min, needling the horizontal outer orbital edge and the avoidance of manipulation during treatment were the most frequent descriptions of the interventions used. Eye acupuncture was used alone in about half of the studies and of the remaining studies it was combined with other treatment. All studies suggested some beneficial effects including: pain relief, improved quality of life and mental health, and 18 (22.2%) adverse events. Eye acupuncture, predominantly studied in China, may be a promising intervention for managing diverse pain conditions. However, given the variety of study designs and reported treatment outcomes, conclusions about the evidence for eye acupuncture for specific conditions are not possible at this stage

    A balanced homodyne detector for high-rate Gaussian-modulated coherent-state quantum key distribution

    Full text link
    We discuss excess noise contributions of a practical balanced homodyne detector in Gaussian-modulated coherent-state (GMCS) quantum key distribution (QKD). We point out the key generated from the original realistic model of GMCS QKD may not be secure. In our refined realistic model, we take into account excess noise due to the finite bandwidth of the homodyne detector and the fluctuation of the local oscillator. A high speed balanced homodyne detector suitable for GMCS QKD in the telecommunication wavelength region is built and experimentally tested. The 3dB bandwidth of the balanced homodyne detector is found to be 104MHz and its electronic noise level is 13dB below the shot noise at a local oscillator level of 8.5*10^8 photon per pulse. The secure key rate of a GMCS QKD experiment with this homodyne detector is expected to reach Mbits/s over a few kilometers.Comment: 22 pages, 11 figure

    57Fe Mossbauer spectroscopy and magnetic measurements of oxygen deficient LaFeAsO

    Full text link
    We report on the magnetic behavior of oxygen deficient LaFeAsO1-x (x-0.10) compound, prepared by one-step synthesis, which crystallizes in the tetragonal (S.G. P4/nmm) structure at room temperature. Resistivity measurements show a strong anomaly near 150 K, which is ascribed to the spin density wave (SDW) instability. On the other hand, dc magnetization data shows paramagnetic-like features down to 5 K, with an effective moment of 0.83 mB/Fe. 57Fe Mossbauer studies (MS) have been performed at 95 and 200 K. The spectra at both temperatures are composed of two sub-spectra. At 200 K the major one (88%), is almost a singlet, and corresponds to those Fe nuclei, which have two oxygen ions in their close vicinity. The minor one, with a large quadrupole splitting, corresponds to Fe nuclei, which have vacancies in their immediate neighborhood. The spectrum at 95 K, exhibits a broadened magnetic split major (84%) sub-spectrum and a very small magnetic splitting in the minor subspectrum. The relative intensities of the subspectra facilitate in estimating the actual amount of oxygen vacancies in the compound to be 7.0(5)%, instead of the nominal LaFeAsO0.90. These results, when compared with reported 57Fe MS of non-superconducting LaFeAsO and superconducting LaFeAsO0.9F0.1, confirm that the studied LaFeAsO0.93 is a superconductivity-magnetism crossover compound of the newly discovered Fe based superconducting family.Comment: 7 pages text + Figs : Comments/suggestions welcome ([email protected]

    Transient heat generation in a quantum dot under a step-like pulse bias

    Full text link
    We study the transient heat generation in a quantum dot system driven by a step-like or a square-shaped pulse bias. We find that a periodically oscillating heat generation arises after adding the sudden bias. One particularly surprising result is that there exists a heat absorption from the zero-temperature phonon subsystem. Thus the phonon population in non-equilibrium can be less than that of the equilibrium electron-phonon system. In addition, we also ascertain the optimal conditions for the operation of a quantum dot with the minimum heat generation.Comment: 6 pages, 4 figure
    corecore