944 research outputs found

    A 2.4 - 12 microns spectrophotometric study with ISO of Cygnus X-3 in quiescence

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    We present mid-infrared spectrophotometric results obtained with the ISO on the peculiar X-ray binary Cygnus X-3 in quiescence, at orbital phases 0.83 to 1.04. The 2.4-12 microns continuum radiation observed with ISOPHOT-S can be explained by thermal free-free emission in an expanding wind with, above 6.5 microns, a possible additional black-body component with temperature T ~ 250 K and radius R ~ 5000 solar radii at 10 kpc, likely due to thermal emission by circumstellar dust. The observed brightness and continuum spectrum closely match that of the Wolf-Rayet star WR 147, a WN8+B0.5 binary system, when rescaled at the same 10 kpc distance as Cygnus X-3. A rough mass loss estimate assuming a WN wind gives ~ 1.2 10^{-4} M(sun)/yr. A line at ~ 4.3 microns with a more than 4.3 sigma detection level, and with a dereddened flux of 126 mJy, is interpreted as the expected He I 3p-3s line at 4.295 microns, a prominent line in the WR 147 spectrum. These results are consistent with a Wolf-Rayet-like companion to the compact object in Cygnus X-3 of WN8 type, a later type than suggested by earlier works.Comment: 8 pages, 10 figures ; Accepted in A&

    The spiral galaxy M33 mapped in the FIR by ISOPHOT: A spatially resolved study of the warm and cold dust

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    The Sc galaxy M33 has been mapped with ISOPHOT in the far-infrared, at 60, 100, and 170mue. The spatial resolution of these FIR maps allows the separation of spiral arms and interarm regions and the isolation of a large number of star-forming regions. The spectral energy distribution in the FIR indicates a superposition of two components, a warm one originating from dust at ~45K, and a cold one, at ~16K. The warm component is concentrated towards the spiral arms and the star-forming regions, and is likely heated by the UV radiation from OB stars. The cold component is more smoothly distributed over the disk, and heated by the diffuse interstellar radiation. For the about 60 star-forming regions detected the H-alpha/FIR flux ratio increases significantly with the distance from the galaxy center, probably due to decreasing extinction. An anti-correlation of F_Ha/F_60 with F_170 suggests the intrinsic extinction to be related to the cold dust surface brightness according to A_V/S_170~0.03mag/MJy*sr. For the total galaxy the star formation rate (SFR) derived from the FIR is in agreement with that derived from the de-extincted H-alpha emission. For individual star-forming regions, a consistency between SFRs derived from the optical and from the FIR requires only a fraction of the UV radiation to be absorbed locally. The individual star-forming regions also show a local radio-FIR correlation. This local correlation is, however, due to quite different components than to those that lead to the well-known global radio-FIR correlation for entire galaxies.Comment: 10 pages, 9 figures; the full resolution images of Fig.1 can be obtained by anonymous ftp from ftp.mpia.de /pub/iso-arc

    Anti-myeloma efficacy of CAR-iNKT is enhanced with a long-acting IL-7, rhIL-7-hyFc

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    Multiple myeloma (MM), a malignancy of mature plasma cells, remains incurable. B-cell maturation antigen (BCMA) is the lead protein target for chimeric antigen receptor (CAR) therapy because of its high expression in most MM, with limited expression in other cell types, resulting in favorable on-target, off tumor toxicity. The response rate to autologous BCMA CAR-T therapy is high; however, it is not curative and is associated with risks of cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome. Outcomes in patients treated with BCMA CAR-T cells (CAR-Ts) may improve with allogeneic CAR T-cell therapy, which offer higher cell fitness and reduced time to treatment. However, to prevent the risk of graft-versus-host disease (GVHD), allogenic BCMA CAR-Ts require genetic deletion of the T-cell receptor (TCR), which has potential for unexpected functional or phenotype changes. Invariant natural killer T cells (iNKTs) have an invariant TCR that does not cause GVHD and, as a result, can be used in an allogeneic setting without the need for TCR gene editing. We demonstrate significant anti-myeloma activity of BCMA CAR-iNKTs in a xenograft mouse model of myeloma. We found that a long-acting interleukin-7 (IL-7), rhIL-7-hyFc, significantly prolonged survival and reduced tumor burden in BCMA CAR-iNKT-treated mice in both primary and re-challenge settings. Furthermore, in CRS in vitro assays, CAR-iNKTs induced less IL-6 than CAR-Ts, suggesting a reduced likelihood of CAR-iNKT therapy to induce CRS in patients. These data suggest that BCMA CAR-iNKTs are potentially a safer, effective alternative to BCMA CAR-Ts and that BCMA CAR-iNKT efficacy is further potentiated with rhIL-7-hyFc

    CS1 CAR-T targeting the distal domain of CS1 (SLAMF7) shows efficacy in high tumor burden myeloma model despite fratricide of CD8+CS1 expressing CAR-T cells

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    Despite improvement in treatment options for myeloma patients, including targeted immunotherapies, multiple myeloma remains a mostly incurable malignancy. High CS1 (SLAMF7) expression on myeloma cells and limited expression on normal cells makes it a promising target for CAR-T therapy. The CS1 protein has two extracellular domains - the distal Variable (V) domain and the proximal Constant 2 (C2) domain. We generated and tested CS1-CAR-T targeting the V domain of CS1 (Luc90-CS1-CAR-T) and demonstrated anti-myeloma killing in vitro and in vivo using two mouse models. Since fratricide of CD8 + cells occurred during production, we generated fratricide resistant CS1 deficient Luc90- CS1- CAR-T (ΔCS1-Luc90- CS1- CAR-T). This led to protection of CD8 + cells in the CAR-T cultures, but had no impact on efficacy. Our data demonstrate targeting the distal V domain of CS1 could be an effective CAR-T treatment for myeloma patients and deletion of CS1 in clinical production did not provide an added benefit using in vivo immunodeficient NSG preclinical models

    A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)

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    We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb−1{\rm fb}^{-1} recorded at the ΄(4S)\Upsilon(4S) resonance and 3.9 fb−1{\rm fb}^{-1} off-resonance. One of the neutral B mesons, which are produced in pairs at the ΄(4S)\Upsilon(4S), is fully reconstructed in the CP decay modes J/ψKS0J/\psi K^0_S, ψ(2S)KS0\psi(2S) K^0_S, χc1KS0\chi_{c1} K^0_S, J/ψK∗0J/\psi K^{*0} (K∗0→KS0π0K^{*0}\to K^0_S\pi^0) and J/ψKL0J/\psi K^0_L, or in flavor-eigenstate modes involving D(∗)π/ρ/a1D^{(*)}\pi/\rho/a_1 and J/ψK∗0J/\psi K^{*0} (K∗0→K+π−K^{*0}\to K^+\pi^-). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample finds Δmd=0.516±0.016(stat)±0.010(syst)ps−1\Delta m_d = 0.516\pm 0.016 {\rm (stat)} \pm 0.010 {\rm (syst)} {\rm ps}^{-1}. The value of the asymmetry amplitude sin⁥2ÎČ\sin2\beta is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B0B^0 decays in the CP-eigenstate modes. We find sin⁥2ÎČ=0.59±0.14(stat)±0.05(syst)\sin2\beta=0.59\pm 0.14 {\rm (stat)} \pm 0.05 {\rm (syst)}, demonstrating that CP violation exists in the neutral B meson system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review

    Evaluation of Geostationary Lightning Mapper (GLM) Navigation Performance with the INR Performance Assessment Toolset (IPATS)

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    The GOES-R flight project has developed the Image Navigation and Registration (INR) Performance Assessment Tool Set (IPATS) to perform independent INR evaluations of the optical instruments on the GOES-R series spacecraft. In this presentation, we document the development of navigation (NAV) evaluation capabilities within IPATS for the Geostationary Lightning Mapper (GLM). We also discuss the post-processing quality filtering developed for GLM NAV, and present example results for several GLM background image datasets. Initial results suggest that GOES-16 GLM is compliant with navigation requirements

    Measurement of the branching fraction and CP content for the decay B(0) -> D(*+)D(*-)

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    This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APS.We report a measurement of the branching fraction of the decay B0→D*+D*- and of the CP-odd component of its final state using the BABAR detector. With data corresponding to an integrated luminosity of 20.4  fb-1 collected at the ΄(4S) resonance during 1999–2000, we have reconstructed 38 candidate signal events in the mode B0→D*+D*- with an estimated background of 6.2±0.5 events. From these events, we determine the branching fraction to be B(B0→D*+D*-)=[8.3±1.6(stat)±1.2(syst)]×10-4. The measured CP-odd fraction of the final state is 0.22±0.18(stat)±0.03(syst).This work is supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the A.P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation

    Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events

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    The B0B^0-Bˉ0\bar B^0 oscillation frequency has been measured with a sample of 23 million \B\bar B pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we select events in which both B mesons decay semileptonically and use the charge of the leptons to identify the flavor of each B meson. A simultaneous fit to the decay time difference distributions for opposite- and same-sign dilepton events gives Δmd=0.493±0.012(stat)±0.009(syst)\Delta m_d = 0.493 \pm 0.012{(stat)}\pm 0.009{(syst)} ps−1^{-1}.Comment: 7 pages, 1 figure, submitted to Physical Review Letter

    Measurement of D-s(+) and D-s(*+) production in B meson decays and from continuum e(+)e(-) annihilation at √s=10.6 GeV

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    This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APSNew measurements of Ds+ and Ds*+ meson production rates from B decays and from qq̅ continuum events near the ΄(4S) resonance are presented. Using 20.8 fb-1 of data on the ΄(4S) resonance and 2.6 fb-1 off-resonance, we find the inclusive branching fractions B(B⃗Ds+X)=(10.93±0.19±0.58±2.73)% and B(B⃗Ds*+X)=(7.9±0.8±0.7±2.0)%, where the first error is statistical, the second is systematic, and the third is due to the Ds+→φπ+ branching fraction uncertainty. The production cross sections σ(e+e-→Ds+X)×B(Ds+→φπ+)=7.55±0.20±0.34pb and σ(e+e-→Ds*±X)×B(Ds+→φπ+)=5.8±0.7±0.5pb are measured at center-of-mass energies about 40 MeV below the ΄(4S) mass. The branching fractions ÎŁB(B⃗Ds(*)+D(*))=(5.07±0.14±0.30±1.27)% and ÎŁB(B⃗Ds*+D(*))=(4.1±0.2±0.4±1.0)% are determined from the Ds(*)+ momentum spectra. The mass difference m(Ds+)-m(D+)=98.4±0.1±0.3MeV/c2 is also measured.This work was supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the Swiss NSF, A. P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation
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