71 research outputs found

    Revisit of cosmic ray antiprotons from dark matter annihilation with updated constraints on the background model from AMS-02 and collider data

    Get PDF
    We study the cosmic ray antiprotons with updated constraints on the propagation, proton injection, and solar modulation parameters based on the newest AMS-02 data near the Earth and Voyager data in the local interstellar space, and on the cross section of antiproton production due to proton-proton collisions based on new collider data. We use a Bayesian approach to properly consider the uncertainties of the model predictions of both the background and the dark matter (DM) annihilation components of antiprotons. We find that including an extra component of antiprotons from the annihilation of DM particles into a pair of quarks can improve the fit to the AMS-02 antiproton data considerably. The favored mass of DM particles is about 60∌10060\sim100 GeV, and the annihilation cross section is just at the level of the thermal production of DM (⟚σv⟩∌O(10−26)\langle\sigma v\rangle \sim O(10^{-26}) cm3^3~s−1^{-1}).Comment: 15 pages, 5 figures and 1 table; JCAP accepted versio

    Visualizing the dynamic behavior of poliovirus plus-strand RNA in living host cells

    Get PDF
    Dynamic analysis of viral nucleic acids in host cells is important for understanding virus–host interaction. By labeling endogenous RNA with molecular beacon, we have realized the direct visualization of viral nucleic acids in living host cells and have studied the dynamic behavior of poliovirus plus-strand RNA. Poliovirus plus-strand RNA was observed to display different distribution patterns in living Vero cells at different post-infection time points. Real-time imaging suggested that the translocation of poliovirus plus-strand RNA is a characteristic rearrangement process requiring intact microtubule network of host cells. Confocal-FRAP measurements showed that 49.4 ± 3.2% of the poliovirus plus-strand RNA molecules diffused freely (with a D-value of 9.6 ± 1.6 × 10(−10) cm(2)/s) within their distribution region, while the remaining (50.5 ± 2.9%) were almost immobile and moved very slowly only with change of the RNA distribution region. Under the electron microscope, it was found that virus-induced membrane rearrangement is microtubule-associated in poliovirus-infected Vero cells. These results reveal an entrapment and diffusion mechanism for the movement of poliovirus plus-strand RNA in living mammalian cells, and demonstrate that the mechanism is mainly associated with microtubules and virus-induced membrane structures

    Inflammatory bowel disease and risk of Parkinson’s disease: evidence from a meta-analysis of 14 studies involving more than 13.4 million individuals

    Get PDF
    BackgroundThe relationship between inflammatory bowel disease (IBD) and the risk of Parkinson’s Disease (PD) has been investigated in several epidemiological studies. However, the results of these studies were inconclusive and inconsistent. We evaluated the potential relationship between IBD and PD risk by a meta-analysis.MethodsSearch the electronic databases PubMed, Embase and Cochrane databases from inception to November 30, 2022, to identify relevant studies that assess the risk of PD in patients with IBD. The cohort, cross-sectional, mendelian randomization and case-control studies that reported risk estimates of PD and IBD were included in our analysis. The random-effect model and fixed-effects model were used to calculate the summary relative risks (RRs) with 95% confidence intervals (CIs).ResultsIn total, 14 studies (nine cohort studies, two cross-sectional studies, two mendelian randomization studies and one case-control study) involving more than 13.4 million individuals were analyzed in our analysis. Our results suggested that the risk of PD in IBD patients is moderately increased, with the pooled RR was 1.17 (95% CI: 1.03–1.33, P = 0.019). Omit of any single study from this analysis had little effect on the combined risk estimate. No evidence of publication bias was found. In the subgroup analysis, the combined RR was 1.04 (95% CI: 0.96, 1.12, P = 0.311) for Crohn’s disease (CD), and 1.18 (95% CI: 1.06, 1.31, P = 0.002) for ulcerative colitis (UC). In addition, a significant association was identified in patients with IBD aged ≄ 60 years (RR = 1.22; 95% CI: 1.06–1.41, P = 0.007), but not in age < 60 years (RR = 1.19; 95% CI: 0.58–2.41, P = 0.639). Meanwhile, the meta-analysis results suggested a protective role for IBD medication use against PD development, with the RR was 0.88 (95% CI: 0.74, 1.04, P = 0.126).ConclusionOur results indicated that patients with IBD had a moderately higher risk of PD compared to non-IBD individuals. Patients with IBD should be aware of the potential risks for PD, especially who were ≄ 60 years old

    Experimental observation of quantum state-independent contextuality under no-signaling conditions

    Get PDF
    Contextuality, the impossibility of assigning context-independent measurement outcomes, is a critical resource for quantum computation and communication. No-signaling betweensuccessivemeasurementsisanessentialrequirementthatshouldbeaccomplishedin anytestofquantumcontextualityandthatisdiïŹƒculttoachieveinpractice.Here,weintroduce anoptimalquantumstate-independentcontextualityinequalityinwhichthedeviationfromthe classicalboundismaximal.Wethenexperimentallytestitusingsinglephotonsgeneratedfrom a defect in a bulk silicon carbide, while satisfying the requirement of no-signaling within the experimental error. Our results shed new light on the study of quantum contextuality under no-signalingconditions

    Protective role for collectin‐11 in rheumatoid arthritis in mice

    Get PDF
    OBJECTIVE. Collectin-11 (CL-11) is a soluble C-type lectin, a mediator of innate immunity. Its role in autoimmune disorders is unknown. The goal of this study was to determine the role of CL-11 in a mouse model of rheumatoid arthritis (RA). METHODS. A murine collagen-induced arthritis (CIA) model, combining both gene deletion of Colec11 and recombinant (rCL-11) treatment approaches were employed. Joint inflammation and tissue destruction, circulating levels of inflammatory cytokines and adaptive immune responses were assessed in CIA mice. Splenic CD11c(+) cells were used to examine the influence of CL-11 on antigen presenting cell (APC) function. Serum levels of CL-11 in RA patients were also examined. RESULTS. Colec11(−/−) mice developed more severe arthritis than WT mice (as determined by disease incidence, clinical arthritis scores and histopathology; P<0.05). Disease severity is associated with significantly enhanced APC activation, Th1/Th17 responses, pathogenic IgG2a production and joint inflammation, as well as elevated circulating levels of inflammatory cytokines. In vitro analysis of CD11c(+) cells revealed that CL-11 is critical for suppression of APC activation and function. Pharmacological treatment of mice with rCL-11 reduced the severity of CIA in mice. Analysis of human blood samples revealed that serum levels of CL-11 was lower in RA patients (n=51) compared to healthy controls (n=53), a serum CL-11 reduction also displays a negative relationship with DAS28, ESR and CRP (P<0.05). CONCLUSION. Our findings demonstrate a novel role for CL-11 in protection against RA, suggesting the underlying mechanism involved suppression of APC activation and subsequent T cell responses

    An Updated Search of Steady TeV γ−\gamma-Ray Point Sources in Northern Hemisphere Using the Tibet Air Shower Array

    Full text link
    Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for TeV γ−\gamma-ray point sources has now been updated by a factor of 2.8 improved statistics. From 0.0∘0.0^{\circ} to 60.0∘60.0^{\circ} in declination (Dec) range, no new TeV γ−\gamma-ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV γ−\gamma-ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits.Comment: This paper has been accepted by hepn
    • 

    corecore