The effect of in vivo stimulation of the phagocytic system (neutrophils, monocytes and hepatic Kupffer-cells) by inducing phagocytosis of intravenously administered latex particles on lipid ...peroxidation and aortic intimal proliferation was tested in cholesterol-fed rabbits. Three weeks after starting the diet, aortic intimal proliferation was measured by the intimal to medial ratios and by the incorporation of 3Hthymidine, infused into the circulation for the preceding 14 days. Intimal to medial ratios were increased (0.473 +/- 0.023 vs. 0.282 +/- 0.011, P < 0.01) and aortic 3Hthymidine contents were higher (66.8 +/- 3.5 vs. 27.8 +/- 49 counts/min per mg, P = 0.0001) in latex bead-treated than in control animals. Injection of beads transiently increased plasma lipid peroxide levels. At the end of the 3 week experiment, plasma lipid peroxide levels were still elevated and lipid peroxide contents of the aortic walls were higher in the latex-treated rabbits (82.8 +/- 5.8 vs. 46.4 +/- 4.9 nmol/mg cholesterol, latex-treated vs. controls, P = 0.004). These data suggest a significant acceleration of atherogenesis by the stimulated phagocytic system, the mechanism of which may involve lipid peroxidation.
For the identification of particles in the momentum range 0.5–2.5GeV/c, the ALICE experiment uses a Time Of Flight array consisting of Multigap Resistive Plate Chambers (MRPC) in the form of long ...strips. The design of the detector elements is as follows : double stack MRPCs with glass resistive plates and 5 gas gaps of 250μm per stack. The latest results on the performance of these MRPCs are presented. Typical values of time resolution σ are better than 50ps, with an efficiency of 99.9% and a long, more than 1.5kV, streamer-free plateau.
We report an observation of the decay B{sub s}{sup 0}{yields}D{sub s}{sup -}{pi}{sup +} in pp collisions at {radical}(s)=1.96 TeV using 115 pb{sup -1} of data collected by the CDF II detector at the ...Fermilab Tevatron. We observe 83{+-}11(stat) B{sub s}{sup 0}{yields}D{sub s}{sup -}{pi}{sup +} candidates, representing a large increase in statistics over previous measurements and the first observation of this decay at a pp collider. We present the first measurement of the relative branching fraction B(B{sub s}{sup 0}{yields}D{sub s}{sup -}{pi}{sup +})/B(B{sup 0}{yields}D{sup -}{pi}{sup +})=1.32{+-}0.18(stat){+-}0.38(syst). We also measure B(B{sup +}{yields}D{sup 0}{pi}{sup +})/B(B{sup 0}{yields}D{sup -}{pi}{sup +})=1.97{+-}0.10(stat){+-}0.21(syst), which is consistent with previous measurements.
Symbolic manipulation (REDUCE and SCHOONSCHIP) has been applied to the analytic evaluation of the coefficients in the Taylor series expansion of time-correlation functions. These expressions are ...derived for cylindrically and biaxially symmetric particles reorienting in a uniaxial fluid. The possibility of using computer algebra to determine correlation-function moments should make it applicable to various problems in statistical physics.
In this work, we expand on the XENON1T nuclear recoil searches to study the individual signals of dark matter interactions from operators up to dimension-eight in a Chiral Effective Field Theory ...(ChEFT) and a model of inelastic dark matter (iDM). We analyze data from two science runs of the XENON1T detector totaling 1\,tonne\(\times\)year exposure. For these analyses, we extended the region of interest from 4.9, 40.9\(\,\)keV\(_{\text{NR}}\) to 4.9, 54.4\(\,\)keV\(_{\text{NR}}\) to enhance our sensitivity for signals that peak at nonzero energies. We show that the data is consistent with the background-only hypothesis, with a small background over-fluctuation observed peaking between 20 and 50\(\,\)keV\(_{\text{NR}}\), resulting in a maximum local discovery significance of 1.7\,\(\sigma\) for the Vector\(\otimes\)Vector\(_{\text{strange}}\) (\(VV_s\)) ChEFT channel for a dark matter particle of 70\(\,\)GeV/c\(^2\), and \(1.8\,\sigma\) for an iDM particle of 50\(\,\)GeV/c\(^2\) with a mass splitting of 100\(\,\)keV/c\(^2\). For each model, we report 90\,\% confidence level (CL) upper limits. We also report upper limits on three benchmark models of dark matter interaction using ChEFT where we investigate the effect of isospin-breaking interactions. We observe rate-driven cancellations in regions of the isospin-breaking couplings, leading to up to 6 orders of magnitude weaker upper limits with respect to the isospin-conserving case.
The XENON collaboration has published stringent limits on specific dark matter -nucleon recoil spectra from dark matter recoiling on the liquid xenon detector target. In this paper, we present an ...approximate likelihood for the XENON1T 1 tonne-year nuclear recoil search applicable to any nuclear recoil spectrum. Alongside this paper, we publish data and code to compute upper limits using the method we present. The approximate likelihood is constructed in bins of reconstructed energy, profiled along the signal expectation in each bin. This approach can be used to compute an approximate likelihood and therefore most statistical results for any nuclear recoil spectrum. Computing approximate results with this method is approximately three orders of magnitude faster than the likelihood used in the original publications of XENON1T, where limits were set for specific families of recoil spectra. Using this same method, we include toy Monte Carlo simulation-derived binwise likelihoods for the upcoming XENONnT experiment that can similarly be used to assess the sensitivity to arbitrary nuclear recoil signatures in its eventual 20 tonne-year exposure.
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