PubMed | Besancon University Hospital Center, Lyon University Hospital Center, IGR, Nice University Hospital Center and 14 more.
Type: Journal Article | Journal: Cancer medicine | Year: 2016
We have retrospectively compared survivals between acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) patients who received either a clofarabine/busulfan (CloB2A2) or a fludarabine/busulfan (FB2A2) RIC regimen for allogeneic stem cell transplantation. Between 2009 and 2014, 355 allotransplanted cases were identified from the SFGM-TC registry as having received either the FB2A2 (n=316, 56% males, median age: 59.2years, AML 78.5%, first complete remission [CR1] 72%, median follow-up: 20months) or the CloB2A2 (n=39, 62% males, median age: 60.8years, AML 62%, CR1 69%, median follow-up: 22.4months) RIC regimen. In multivariate analysis, FB2A2 was associated with significant lower overall survival (OS, HR: 2.14; 95%CI: 1.05-4.35, P=0.04) and higher relapse incidence (RI, HR: 2.17; 95%CI: 1.02-4.61, P=0.04) and a trend for lower leukemia-free survival (LFS, HR: 1.75; 95%CI: 0.94-3.26, P=0.08). These results were confirmed using a propensity score-matching strategy. However, when considering AML and MDS patients separately, the benefit of the CLOB2A2 regimen was restricted to AML patients (2-year OS FB2A2: 38% [14.5-61.6] vs. CloB2A2: 79.2% [62.9-95.4], P=0.01; 2-year LFS FB2A2: 38% [16-59.9] vs. CloB2A2: 70.8% [52.6-89], P=0.03). The better survivals were due to the lower risk of relapse in this CloB2A2 AML subgroup (2-year RI FB2A2: 41.2% [19-62.4] vs. CloB2A2: 16.7% [5-34.2], P=0.05). This retrospective comparison suggests that the CloB2A2 RIC regimen can likely provide longer survival than that awarded by a FB2A2 RIC regimen and may become a new standard of care RIC regimen for allotransplanted AML patients. A prospective phase 3 randomized study is warranted.
News Article | December 12, 2016
PHILADELPHIA--(BUSINESS WIRE)--The Board of Trustees of the CBRE Clarion Global Real Estate Income Fund (NYSE: IGR) (the “Fund”) has declared a monthly distribution of $0.05 per share for the month of December 2016. The following dates apply: IGR’s current annualized distribution rate is 8.3% based on the closing market price of $7.23 on December 8, 2016, and 6.9% based on a closing NAV of $8.66 as of the same date. Future earnings of the Fund cannot be guaranteed, and the Fund’s distribution policy is subject to change. For more information on the Fund, please visit www.cbreclarion.com. The Fund’s monthly distribution is set by its Board of Trustees. The Board reviews the Fund’s distribution on a quarterly basis in view of its net investment income, realized and unrealized gains, and other net unrealized appreciation or income expected during the remainder of the year. The Fund strives to establish a level monthly distribution that, over the course of the year, will serve to distribute an amount closely approximating the Fund’s net investment income and net realized capital gains during the year. CBRE Clarion Global Real Estate Income Fund is a closed-end fund, which is traded on the New York Stock Exchange and invests primarily in real estate securities. Holdings are subject to change. Past performance is no guarantee of future results. For the current fiscal year (January 1, 2016 to December 31, 2016), the Fund has made or declared twelve (12) regular monthly distributions totaling $0.60 per share. The source of the distributions declared for the current month and fiscal year to date is estimated as follows: The allocations reported in this notice are only estimates and are not provided for tax reporting purposes. The actual allocations will depend on the Fund’s investment experience during the remainder of its fiscal year and will not be finalized until after year-end. In addition, the allocations reported to shareholders for tax reporting purposes will also reflect adjustments required under applicable tax regulations. Some of these tax adjustments are significant, and amounts reported to you for tax reporting may be substantially different than those presented in this notice. SHAREHOLDERS WILL BE SENT A FORM 1099-DIV FOR THE CALENDAR YEAR INDICATING HOW TO REPORT FUND DISTRIBUTIONS FOR FEDERAL INCOME TAX PURPOSES. The estimated allocations presented above are based on the Fund’s monthly calculation of its year-to-date net investment income, capital gains and returns of capital. 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Shareholders should take note of the relationship between the Cumulative Total Return and the Fund’s Cumulative Distribution Rate for 2016, as well as its Current Annualized Distribution Rate. Moreover, the Fund’s Average Annual Total Return for the preceding five-year period (December 1, 2011 through November 30, 2016) is set forth below. Shareholders should take note of the relationship between the Fund’s Average Annual Total Return and its Average Annual Distribution Rate for the preceding five-year period. Please refer to the chart below for information about the Fund’s historical NAVs, change in NAVs, total returns, and distributions paid. Sources: NAV per share amounts and annualized total returns are published in the Fund’s audited annual reports for the respective year. CBRE Clarion Securities is a registered investment advisory firm specializing in the management of global real asset securities for institutional investors. Headquartered near Philadelphia, the firm manages $20.1 billion in assets as of September 30, 2016, and has over 90 employees located in offices in the United States, United Kingdom, Hong Kong, Japan, and Australia. For more information about CBRE Clarion Securities, please visit www.cbreclarion.com. CBRE Clarion Securities is the listed equity management arm of CBRE Global Investors. CBRE Global Investors is a global real estate investment management firm with $87.9 billion in assets under management* as of September 30, 2016. The firm sponsors investment programs across the risk/return spectrum for investors worldwide. CBRE Global Investors is an independently operated affiliate of CBRE Group, Inc. (NYSE:CBG). It harnesses the research, investment sourcing and other resources of the world’s premier, full-service commercial real estate services and investment company for the benefit of its investors. CBRE Group, Inc. has more than 70,000 employees in more than 400 offices (excluding affiliates) worldwide. For more information about CBRE Global Investors, please visit www.cbreglobalinvestors.com. * Assets under management (AUM) refers to the fair market value of real estate-related assets with respect to which CBRE Global Investors provides, on a global basis, oversight, investment management services and other advice, and which generally consist of investments in real estate; equity in funds and joint ventures; securities portfolios; operating companies and real estate-related loans. This AUM is intended principally to reflect the extent of CBRE Global Investors' presence in the global real estate market, and its calculation of AUM may differ from the calculations of other asset managers.
Is quantitative oestrogen receptor expression useful in the evaluation of the clinical prognosis? Analysis of a homogeneous series of 797 patients with prospective determination of the ER status using simultaneous EIA and IHC
Mazouni C.,Institute Gustave Roussy |
Mazouni C.,Laboratoire Of Transfert Biologique Oncologique |
Bonnier P.,Institute Beauregard |
Goubar A.,IGR |
And 2 more authors.
European Journal of Cancer | Year: 2010
Objective: Oestrogen receptor (ER) determination in breast cancer (BC) is a major yardstick for the prognosis and for response to hormonal therapy (HT). As several techniques have been proposed for ER quantification, the purpose of our study was to assess whether the qualitative or quantitative analysis of ER expression might influence the prognosis and response to treatment. Materials and methods: We analysed overall survival (OS) and disease-free survival (DFS) in 797 primary BC cases with ER determination by enzyme immunoassay (EIA) and immunohistochemistry (IHC). The clinical impact according to qualitative or quantitative analysis of ER expression was assessed. Response to HT was evaluated according to quantitative EIA-determined ER expression levels. Results: According to the qualitative analysis of ER expression, patients with EIA-determined and IHC-determined ER-positive tumours had significantly longer OS and DFS (p < 0.001). The analysis stratified on quartiles of ER levels showed significantly different outcomes according to EIA- and IHC-determined subgroups. In the group of patients who received adjuvant treatment, 5-year OS was significantly different between the groups, with a clear benefit for the highest EIA-determined ER quartiles (p < 0.001). Comparatively, in terms of 5-year DFS, a clear separation was noted between groups for adjuvant treatment (p < 0.001). The group with moderate ER+ values was clearly distinct from the ER-negative population. Quantitative ER expression helped to better distinguish the beneficial or detrimental effect of HT within quartiles of ER-expressing tumours. Based on the STEPP analysis which showed a trend towards an ER effect on DFS as a function of HT assignment, we confirm the benefit of HT in patients with a very high EIA-determined ER level and a detrimental impact on negative and weakly positive groups. Conclusion: Quantitative ER expression in BC helps to better discriminate heterogeneity in clinical outcome and response to HT. © 2010 Elsevier Ltd. All rights reserved.
News Article | February 22, 2017
IGR J17062−6143 is an accreting neutron star binary, first observed during an outburst in 2006. Two years later, this object was observed by the RXTE satellite, which acquired important data about its activity. The data provided by RXTE was recently analyzed by Tod Strohmayer and Laurens Keek of NASA's Goddard Space Flight Center in Greenbelt, Maryland, in order to find pulsations of this source. They extracted light curves, spectra, and an estimate of the background spectrum during the observation. The available data allowed them to gather compelling evidence indicating that IGR J17062−6143 harbors an X-ray pulsar. "We present the discovery of 163.65 Hz X-ray pulsations from IGR J17062−6143 in the only observation obtained from the source with the Rossi X-ray Timing Explorer," the paper reads. The pulsations were detected in the 2.0 to 12 keV band. The team searched for pulsations in the frequency range from 10 to 2048 Hz and noticed a strong peak near 163.65 Hz. The discovery makes IGR J17062−6143 the lowest-frequency accreting millisecond X-ray pulsar known to date. All other accreting millisecond X-ray pulsars have spin frequency over 182 Hz. Moreover, the researchers found that the pulse frequency varies with time in a manner consistent with orbital motion of the neutron star. This conclusion was drawn after dynamic power spectra were computed in order to determine if any secular variations in the pulsation frequency could be produced by orbital motion of the neutron star. The team also tried to determine the orbital period of IGR J17062−6143. However, due to the short observation interval, they were not able to precisely calculate it, but only estimated that it should be no shorter than 17 minutes. "We can find acceptable circular orbits with periods longward of about 20 minutes, however, periods shorter than this are disfavored, and we determined a 90 percent confidence lower limit on the orbital period of 17 minutes," the researchers wrote in the paper. Determining the orbital period of this pulsar could be essential for understanding more clearly its accretion geometry. It could also help reveal the composition of the accreted material. That is why the team calls for further studies of the orbital period of IGR J17062−6143. "As we have described, the RXTE/PCA observation was too short to accurately determine the orbital period; therefore, future timing observations are needed, for example, with the Neutron Star Interior Composition Explorer (NICER) which is scheduled for launch in 2017," the scientists concluded. NICER is planned to be attached to the International Space Station, where it will carry out rotation-resolved spectroscopy of the thermal and non-thermal emissions of neutron stars in the soft (0.2 to 12 keV) X-ray band with unprecedented sensitivity. More information: IGR J17062-6143 is an Accreting Millisecond X-ray Pulsar, arXiv:1702.05449 [astro-ph.HE] arxiv.org/abs/1702.05449 Abstract We present the discovery of 163.65 Hz X-ray pulsations from IGR J17062-6143 in the only observation obtained from the source with the Rossi X-ray Timing Explorer. This detection makes IGR J17062-6143 the lowest-frequency accreting millisecond X-ray pulsar presently known. The pulsations are detected in the 2 - 12 keV band with an overall significance of 4.3 sigma, and an observed pulsed amplitude of 5.54 +- 0.67 % (in this band). Both dynamic power spectral and coherent phase timing analysis indicate that the pulsation frequency is decreasing during the 1.2 ks observation in a manner consistent with orbital motion of the neutron star. Because the observation interval is short, we cannot precisely measure the orbital period; however, periods shorter than 17 minutes are excluded at 90 % confidence. For the range of acceptable circular orbits the inferred binary mass function substantially overlaps the observed range for the AMXP population as a whole.
Relationship between a syntectonic granitic intrusion and a shear zone in the Southern Carpathian-Balkan area (Almâj Mountains, Romania): Implications for late Variscan kinematics and Cherbelezu granitoid emplacement
Plissart G.,Roosevelt University |
Plissart G.,CNRS Nantes Laboratory of Planetology and Geodynamics |
Diot H.,CNRS Nantes Laboratory of Planetology and Geodynamics |
Diot H.,University of La Rochelle |
And 3 more authors.
Journal of Structural Geology | Year: 2012
The Carboniferous Cherbelezu batholith (Almâj Mountains, Romania) is a well-preserved but poorly studied intrusion belonging to the Upper Danubian Alpine Nappe. This pluton crops out along a pre-existing major verticalized formation, the Corbu Mylonitic Zone (CMZ). Our study investigates the role of the CMZ on the deformation recorded during the mush emplacement and cooling. A detailed microstructural study of this granitic body, coupled with investigations on both Anisotropy of Magnetic Susceptibility (AMS) and Shape Preferred Orientation (SPO) of biotite subfabric, has been performed. The surrounding rocks preserve evidence that the CMZ has been reactivated as a sinistral strike-slip fault before the pluton emplacement. Microstructural investigations of the granitic facies indicate that the pluton has undergone superimposed deformations during its cooling, from submagmatic to LT conditions. Foliation and lineation patterns obtained by AMS and SPO - both methods giving similar results - reflect either magmatic/submagmatic or solid-state flows. Magmatic flow, preserved in the western and southern parts of the pluton, is characterized by concentric foliation pattern with both divergent and parallel lineations, the latter pointing to an early transcurrent regime. Subsequently, a solid-state deformation, recorded during the pluton cooling and restricted to its eastern and northern parts, argues for the concomitant CMZ activity under a sinistral transpressive regime. This is supported by the P' and . T parameter distributions, especially for SPO results, this technique showing clear advantages for the interpretation of the fabric scalar parameters. © 2012 Elsevier Ltd.
News Article | January 6, 2016
Immediately after the detection by Swift/BAT on June 15.77197 ut, the VSNET collaboration team31 started a worldwide photometric campaign of V404 Cyg. There was also an independent detection by CCD (charge coupled device) photometry on June 16.169 ut32. Time-resolved CCD photometry was carried out at 27 sites using 36 telescopes with apertures of dozens of centimetres (Extended Data Table 2). We also used the public AAVSO data33. We corrected for bias and flat-fielding in the usual manner, and performed standard aperture photometry. The observers, except for TAOS34, used standard filters (B, V, R , I ; we write R and I for R and I in the main text and figures for brevity) and measured magnitudes of V404 Cyg relative to local comparison stars whose magnitudes were measured by A. Henden (sequence 15167RN) from the AAVSO Variable Star Database35. We applied small zero-point corrections to some observers’ measurements. When filtered observations were unavailable, we used unfiltered data to construct the light curve. The exposure times were mostly 2–30 s, with some exceptional cases of 120 s in B band, giving typical time resolution of a few seconds. All of the observation times were converted to BJD. For the Swift/XRT light curves (Fig. 3 and Extended Data Fig. 2), we extracted source events from a region with a 30-pixel radius centred on V404 Cyg. To avoid pile-up effects, we further excluded an inner circular region if the maximum count rate of the XRT raw light curves, binned in 10 s intervals, exceeded 200 counts s−1. The inner radii are set to be 10 and 20 pixels at the maximum raw rate of 1,000 counts s−1 and 2,000 counts s−1, respectively, and those for intermediate count rates were determined via linear interpolation between the two points. The presented light curves were corrected for photon losses due to this exclusion by using the xrtlccorr tool. In addition, from Fig. 3a, c and d, we can see a time delay in the start of a dip in optical light, relative to that in X-rays. The delay time was ~1 min, which is similar to the reported value of 0–50 s (ref. 36). This was determined by cross-correlating the U-band and X-ray (0.3–10 keV) light curves obtained with Swift/UltraViolet and Optical Telescope (UVOT) and Swift/XRT on ut 2015 June 2136. The observations were carried out when the source showed little rapid optical flickering and no extreme flares, and thus the nature of the lag may be different from that in our observations. We also note that the apparent difference between the Swift/UVOT and the ground-based times36 is caused by the drift of the clock on board the satellite, to which we have applied the necessary corrections. In order to examine the possibility that absorption by gas in the line-of-sight causes the observed violent flux variations in the optical and X-ray bands (Fig. 3), we studied intensity-sliced X-ray spectra. A striking example is shown in Extended Data Fig. 3a. The period shown corresponds to that in Fig. 3a when both the X-ray and optical fluxes exhibited a sudden intensity drop towards the latter part of the period. We divided it into five intervals (T1 to T5; Extended Data Fig. 3a), and generated spectra through the tools xrtpipeline and xrtproducts in standard pipeline processing. We excluded the central 60-arcsecond strip from this Windowed Timing (WT) mode data, to avoid the heavy pile-up effect when the raw count rate exceeds ~150 counts s−1. We compared the vF spectra of the five intervals, where the spectra are fitted by a single power-law model multiplied by photoelectric absorption (phabs × pegpwrlw; in the standard X-ray spectral fitting package XSPEC). The absorbed X-ray flux ranges by two orders of magnitude, from 2.1 × 10−9 erg s−1 cm−2 in T5 to 3.0 × 10−7 erg s−1 cm−2 in T3. However, the best-fit column density and photon index were relatively stable over the five intervals, ~(2–6) × 10−21 cm−2 and ~1.0–1.5, respectively. Since the X-ray spectrum does not show a noticeable rise in column density when the X-ray flux sharply dropped, and since there is no stronger iron edge in the latter part of the observation, absorption cannot be the primary cause of the time variation in our data sets that cover the X-ray and optical bands simultaneously. In Extended Data Table 3 we show the list of X-ray binaries that have shown violent short-term variations either in X-rays or in optical wavelengths. IGR J17091−3624 is known as the second black hole X-ray binary whose X-ray light curves showed a variety of patterns, resembling those of GRS 1915 + 10518. The variations observed in the 2011 outburst of this object were classified as ρ (‘heartbeat’), ν (similar to class ρ but with secondary peak after the dips), α (‘rounded-bumps’), β/λ (repetitive short-term oscillations after low-quiet period) and μ (ref. 18). The Rapid Burster (RB or MXB 1730−335), a low-mass X-ray binary (LMXB) containing a neutron star (NS), was discovered by Small Astronomy Satellite (SAS-3) observations37. This object has been recently reported to show cyclic long X-ray bursts with periods of a few seconds resembling class ρ (‘heartbeat’) variations and those with periods of 100–200 s resembling class θ (“M”-shaped light curves) variations of GRS 1915 + 10524. The emission of the Rapid Burster did not reach the Eddington luminosity during these variations38. V4641 Sgr was originally discovered as a variable star39 and was long confused with a different variable star, GM Sgr40. V4641 Sgr is famous for its short and bright outburst in 1999, which reached a optical magnitude of at least 8.8 mag (refs 41, 42, 43, 44). V4641 Sgr showed short-term variations in optical wavelengths during the 2002, 2003 and 2004 outbursts14, 45, 46, 47. It was the first case in which short-term and large-amplitude variations in the optical range during an outburst were detected. V4641 Sgr is classified as a LMXB, and has a long orbital period. Its mass-accretion rate is less than the Eddington rate (except for the 1999 outburst44, 48). These properties are similar to those of V404 Cyg. However, while the short-term variations of V4641 Sgr seemed to be random, those of V404 Cyg showed repetitive patterns; this is the greatest difference between these two objects. There has been a suggestion that V4641 Sgr is a ‘microblazar’49 because the jets observed during the outburst in 1999 were proposed to have the largest bulk Lorentz factor among known galactic sources43. There are also other X-ray transients showing short-term optical variations (for example, XTE J1118+480 and GX 339−4). However, these two sources are quasi-periodic oscillations (QPOs), characterized by very short periods. The periods are much shorter than those of repetitive patterns (tens of seconds to a few hours) that we discuss in this Letter. Furthermore, the amplitudes of their variations are significantly smaller than those observed in V4641 Sgr4, 50 on timescales longer than tens of seconds. Following the method in ref. 15, we estimated the mass stored in the disk at the onset of the outburst. By integrating the X-ray light curve of Swift/BAT and assuming the spectral model C in table 1 in ref. 15, we obtained a value of 5.0 × 1025 g assuming a radiative efficiency of 10% and a distance of 2.4 ± 0.2 kpc (ref. 8). The mass during the 1989 outburst has been updated to 3.0 × 1025 g by using this updated distance. The stored mass in the 2015 outburst was approximately the same as that in the 1989 one. As discussed in ref. 15, these masses are far smaller than the mass of a fully built-up disk, estimated to be 2.0 × 1028 g, if these outbursts were starting at the outermost region. We compare the published optical light curves of the 1989 and 1938 outbursts51, 52 with our data from the 2015 outburst (Extended Data Fig. 4). We can see that these outbursts have different durations. The 1938 outburst was apparently longer than the others, and it may have had different properties from the 1989 and 2015 ones. The fading rates of the 1989 and 2015 outbursts are significantly larger than those of classical X-ray transients6, or of FRED (fast rise and exponential decline)-type outbursts, such as 0.028 mag d−1 in V518 Per = GRO J0422+32 (ref. 53) and 0.015 mag d−1 in V616 Mon = A0620−00 (ref. 54). This supports the hypothesis that the outbursts in 1989 and 2015 are different from typical outbursts of classical X-ray transients and that the stored disk mass was a factor of ~103 smaller in the 1989 and 2015 outbursts than the mass of a fully built up disk. We performed power spectral analyses on BJD 2,457,193, BJD 2,457,196 and BJD 2,457,200. We used the continuous and regularly sampled high-cadence data set obtained by LCO (Extended Data Table 1) with exposure times of 5 s (on BJD 2,457,193) and 2 s (others). The durations of these observations are 1.4, 3.1 and 2.2 h, respectively. Considering the read-out times of 1 s, the Nyquist frequencies of these observations are 0.08 and 0.17 Hz, respectively. The power spectral densities (PSDs) were calculated using powspec software in the FTOOLS Xronos package on magnitude measurements. We did not apply de-trending of the light curve since the durations of the individual observations were shorter than the timescale of the global variation of the outburst. The power spectra are well expressed by a power law (P ∝ f −Γ ) with an index Γ of 1.9 ± 0.1, 1.8 ± 0.1, and 2.3 ± 0.1 on BJD 2,457,193, 2,457,196 and 2,457,200, respectively (Extended Data Fig. 5). Interpretation of the physical origins on the basis of these variations is difficult, because a power law index of ~2 in the PSDs is often observed in natural phenomena. In this region (f < 0.01 Hz), the power originating in the optical variations of V404 Cyg is significantly higher than that of white noise estimated from the observations. We next summarize the other reports on short-term variations of V404 Cyg during the present outburst. On BJD 2,457,191, this object was observed using the Argos photometer on the 2.1m Otto Struve Telescope at McDonald Observatory with an exposure time of 2 s55. They reported that the power spectrum was dominated by steep red noise. Observations on BJD 2,457,193 and BJD 2,457,194 were also performed using the ULTRACAM attached with the 4.2m William Herschel Telescope on La Palma observatory with a high time resolution (466.8 ms)56. They reported that the variations were dominated by timescales longer than tens of seconds. Although large amplitude flares (0.3–0.4 mag) on timescales shorter than 1 s were reported57, these flares may be of different origin. For the variations with timescales longer than 100 s, our results agree with these reports55, 56. The timescale τ of heating/cooling waves in dwarf novae and X-ray transients58 is a function of the mass of the central object (M ) and radius (r) with the form , where α is the viscosity parameter59. Here, we estimate the disk radius of V404 Cyg assuming that the timescale of the final fading reflected a dwarf nova-type cooling wave. Using the Kepler data of V344 Lyr and V1504 Cyg, we measured a fading rate of 1.5 mag d−1 of the normal outbursts immediately preceding superoutbursts. During the outbursts in V344 Lyr and V1504 Cyg60, the disk radius is expected to be very close to the 3:1 resonance radius. Adopting a typical mass of a white dwarf in a cataclysmic variable (M = 0.83M ; ref. 61), we estimated the disk radius of V404 Cyg to be 7.8 × 1010 cm for a black hole mass of 9M . This is much smaller than the radius (1.2 × 1012 cm) expected for a fully built-up disk15. Extended Data Fig. 6a shows the multi-wavelength SED on BJD 2,457,199.431 to 2,457,199.446, when the source was simultaneously observed in the X-ray, ultraviolet (UV) and optical bands. The optical fluxes in the V and I bands are taken from our photometric data averaged over the period. Note that R -band data are also available but not used here, because of the contamination by the continuum strong Hα line62, 63, 64. The X-ray spectrum is extracted from simultaneous Swift/XRT data (ObsID 00031403058) which were taken in the WT mode. The data are processed through the pipeline processing tool xrtpipeline. The events detected within 20 pixels around the source position are removed to mitigate pile-up effects. The U-band flux is obtained from the Swift/UVOT images with the same ObsID as the XRT, through the standard tool uvot2pha provided by the Swift team. A circular region centred at the source position with a radius of 5 arcsec is adopted as the source extraction region of the UVOT data. The optical, UV and X-ray data are corrected for interstellar extinction/absorption by assuming A (interstellar extinction in the V band) = 4 (ref. 65) and using the extinction curve in ref. 66 and the N (hydrogen column density) versus E(B−V) relation in ref. 67. Radio data are from the RATAN-600 observation performed in the same period68. The multi-wavelength SED can be reproduced with the diskir model69, 70, which accounts for the emission from the accretion disk, including the effects of Comptonization in the inner disk and reprocessing in the outer disk. We find that partial covering X-ray absorption (using the pcfabs model implemented in the spectral analysis software XSPEC) improves the quality of the fit significantly. The inner-disk temperature is estimated to be 0.12 ± 0.01 keV, and the electron temperature and photon index of the Comptonization component, the ratio between the luminosity of the Compton tail and disk blackbody (L /L ), and the fraction of the bolometric flux thermalized in the outer disk (f ), are 17.5 ± 0.8 keV, 1.78 ± 0.03, 1.17 ± 0.03, and , respectively (the errors in this section represent 90% confidence ranges for one parameter). The inner radius (R ) is estimated to be (1.5–5.4) × 108 cm, and the outer radius (R ) is (2.5 ± 0.3) × 1012 cm. The derived value of R is comparable to or even larger than the binary separation (~2.2 × 1012 cm). However, it could be smaller due to uncertainties in interstellar/circumbinary extinction71 and/or the contribution of jet emission. For instance, if A is 0.4 mag larger than the assumed value (4.0), R becomes (1.9 ± 0.2) × 1012 cm. The maximum achievable radius of a stable disk for a q (mass ratio) = 0.06 object (Extended Data Table 3) is around 0.62A (radius of the 2:1 resonance) to ~0.7A (tidal limit), where A is the binary separation72. Considering the uncertainties, the result of our analysis (>~ 0.77A) is compatible with this maximum radius. Our result appears to favour a large A value. For the partial covering absorber, the best-fit value of the column density is cm−2 and that of the covering fraction is 64 ± 4%. The radio SED can be approximated by a power-law with a photon index of ~1, as in other black hole binaries in the low/hard state73. This profile is likely to be generated by the optically-thick synchrotron emission from compact jets74. Because an optically-thick synchrotron spectrum often extends up to the millimetre to near-infrared bands75, 76, 77, it may contribute to the optical fluxes, in particular at longer wavelengths. The blackbody emission from the companion, a K3III-type star7 with a radius of ~3 R and a temperature of ~4,320 K, contributes to the SED negligibly. Extended Data Figure 6b plots the simultaneous SED on BJD 2,457,191.519 to 2,457,191.524, which is ~2 orders of magnitude fainter in the X-ray band than that shown in the left panel. The X-ray, UV and optical data are taken from the Swift data (ObsID 00031403038) and our photometric measurements in the same manner as described above. This SED can be reproduced with the irradiated disk model as well, with somewhat smaller photon index and inner-disk temperature (<0.07 keV), and a larger than those on BJD 2,457,199.431 to 2,457,199.446. The bolometric luminosity L of V404 Cyg is evaluated based on the hard X-rays above ~15 keV where the intrinsic spectrum is less affected by an absorption. We processed the Swift/BAT archival survey data via batsurvey in the HEAsoft package to derive count rates with individual exposures of ~300 s. Even within this short exposure, photon statistics are good during bright states (>0.05 counts s−1). Assuming a Crab-like spectrum (1 Crab ≈ 0.039 counts s−1), the BAT count rates R (counts s−1) are then converted into 15–50 keV flux (F ) and luminosity (L ) using F = 3.6 × 10−7R (erg s−1 cm−1) and a fiducial distance of 2.4 kpc, respectively. In Fig. 4, we show L after multiplying by a conversion factor L /L = 7 determined from SED modelling (previous section). We find that this bolometric correction factor lies within the range 2.5–10 by fitting 19 X-ray(XRT)-optical simultaneous SED in different periods between BJD 2,457,192.019 and 2,457,201.011. Since the BAT survey data are rather sparse, in order to catch shorter-term variations, we further overlaid the INTEGRAL IBIS/ISGRI monitoring in the 25–60 keV band available at ref. 78, assuming a conversion parameter of 1 Crab rate to be 172.1 counts s−1 and a bolometric correction factor of L /L = 9.97. The luminosity was highly variable during the outburst, changing by five orders of magnitude. While V404 Cyg sometimes reaches the Eddington luminosity (L ) at the peak of multiple sporadic flares, it also repeatedly dropped below 1–10% of L (Fig. 4). At earlier phases of this outburst, the characteristic oscillation already occurred during a lower luminosity state, as discussed in the main text. No statistical methods were used to predetermine sample size.
News Article | October 13, 2016
Discovered in 2003 by ESA's International Gamma-Ray Astrophysics Laboratory (INTEGRAL) space observatory, IGR J17544-2619 has a quiescent X-ray luminosity and one of the shortest measured orbital periods among SFXTs – about 4.9 days. The source also showcases the most extreme X-ray variability among all other SFXTs. In March 2015, Bozzo's team conducted a multi-wavelength observational campaign of IGR J17544-2619, using ESA's X-ray Multi-Mirror Mission (XMM–Newton) and NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) spacecraft. By observing the source simultaneously with both space observatories, the scientists managed to catch it in an initial faint X-ray state and then while undergoing a bright X-ray outburst. "We report on a 150 ks-long observational campaign performed in the direction of IGR J17544-2619 simultaneously with XMM–Newton and NuSTAR. During these observations, the source remained in a very low quiescent state for most of the time, and then, toward the end of the observations, it underwent a bright outburst comprising three distinct short flares lasting in total about 7 ks," the researchers wrote in the paper. As was noted by the team, IGR J17544-2619 was initially caught by both telescopes during an extended quiescent period, which covered the first 33 hours and 20 minutes of observations. However, this state of quiescence did not deliver the expected crucial information on the nature of the source, as the statistics of the data were too low to carry out a time-resolved spectral analysis. When a bright outburst abruptly interrupted the quiescent period, it enabled the team to obtain invaluable information about the activity of this source. The outburst happened at the end of the X-ray observations and lasted nearly two hours. This violent event consisted of three distinct fast flares, among which the first was the faintest one and the other two achieved a luminosity 1,600 times brighter than quiescence. The second flare allowed the scientists to observe significant spectral variability. The researchers took advantage of the high statistics and good energy resolution of the instruments aboard the two space telescopes to investigate the properties of the source's X-ray emission during the quiescence and outburst periods. "We studied the spectral variability during outburst and quiescence by using a thermal and bulk Comptonization model that is typically adopted to describe the X-ray spectral energy distribution of young pulsars in high mass X-ray binaries," the paper reads. Complementary to the observations carried out with XMM–Newton and NuSTAR, the scientists also used the X-ray Telescope (XRT) aboard NASA's Swift Gamma-Ray Burst Mission to investigate IGR J17544-2619. Data from XRT showed that the source remained in a low emission state for most of the time. These results are consistent with the known property of all SFXTs being significantly sub-luminous compared to other supergiant X-ray binaries. Explore further: New infrared source detected in supernova remnant RCW 103 More information: Multi-wavelength observations of IGR J17544-2619 from quiescence to outburst, arXiv:1610.02648 [astro-ph.HE] arxiv.org/abs/1610.02648 Abstract In this paper we report on a long multi-wavelength observational campaign of the supergiant fast X-ray transient prototype IGR J17544-2619. A 150 ks-long observation was carried out simultaneously with XMM-Newton and NuSTAR, catching the source in an initial faint X-ray state and then undergoing a bright X-ray outburst lasting about 7 ks. We studied the spectral variability during outburst and quiescence by using a thermal and bulk Comptonization model that is typically adopted to describe the X-ray spectral energy distribution of young pulsars in high mass X-ray binaries. Although the statistics of the collected X-ray data were relatively high we could neither confirm the presence of a cyclotron line in the broad-band spectrum of the source (0.5-40 keV), nor detect any of the previously reported tentative detection of the source spin period. The monitoring carried out with Swift/XRT during the same orbit of the system observed by XMM-Newton and NuSTAR revealed that the source remained in a low emission state for most of the time, in agreement with the known property of all supergiant fast X-ray transients being significantly sub-luminous compared to other supergiant X-ray binaries. Optical and infrared observations were carried out for a total of a few thousands of seconds during the quiescence state of the source detected by XMM-Newton and NuSTAR. The measured optical and infrared magnitudes were slightly lower than previous values reported in the literature, but compatible with the known micro-variability of supergiant stars. UV observations obtained with the UVOT telescope on-board Swift did not reveal significant changes in the magnitude of the source in this energy domain compared to previously reported values.
PubMed | IGR
Type: Journal Article | Journal: Journal of clinical oncology : official journal of the American Society of Clinical Oncology | Year: 2016
1545 Background. Malignant transformation of oligodendrogliomas (ODG) is associated with increased angiogenesis (endothelial hyperplasia, vascular proliferation of leaking vessels and tumor necrosis). Our aim was to evaluate the prognostic value of tumor angiogenesis assessed by pathological and radiological examinations on progression-free (PFS) and overall survival (OS) in patient (pts) with ODG.All pts with ODG consecutively treated in our Institution from 1994-2000. Pathological sections were re-evaluated to confirm the diagnosis of ODs and to assess the degree of nuclear atypia, mitosis, endothelial hyperplasia, and necrosis. CT-scan and/or MRI images were re-analyzed to assess contrast enhancement and necrosis. A multivariate analysis was performed including baseline demographic data, histological and radiological factors associated with tumor angiogenesis and treatment.134 pts with histologically confirmed low grade (WHO grade II, n=49) and anaplastic ODG (WHO grade III, n=85) were analyzed. Univariate analysis showed that prognostic factors associated with better PFS and OS were age <55 (p<0.0001), ODG revealed by seizure (p<0.0001), lack of endothelial hyperplasia (p<0.001), lack of contrast enhancement (p=0.02), and lack of histological/radiological evidence of tumor necrosis (p<0.0001). Multivariate analysis identified necrosis, endothelial hyperplasia and/or contrast enhancement, age, and seizures as independent bad-prognostic factors for OS. This enabled us to defined three pts groups (low, intermediate, and high risk ODG) according to NEVA score using the more robust parameters (necrosis, epilepsy, vessel and age).Endothelial hyperplasia, contrast enhancement, and necrosis that reflect a mutli-step development of tumor angiogenesis are independent factors of bad prognosis in pts with ODG. No significant financial relationships to disclose.
News Article | November 11, 2016
PHILADELPHIA--(BUSINESS WIRE)--The Board of Trustees of the CBRE Clarion Global Real Estate Income Fund (NYSE: IGR) (the “Fund”) has declared a monthly distribution of $0.05 per share for the month of November 2016. The following dates apply: Declaration Date Ex-Dividend Date Record Date Payable Date November 2016 11-01-2016 11-17-2016 11-21-2016 11-30-2016 IGR’s current annualized distribution rate is 8.0% based on the closing market price of $7.49 on November 8, 2016, and 6.
News Article | September 1, 2016
FXTs are very difficult to detect because they occur at unpredictable locations and times and their activity is very brief. INTEGRAL is one of the space observatories capable of detecting such elusive X-ray sources. Since 2002, the spacecraft, equipped in an X-ray detector, is constantly scanning the sky simultaneously in gamma rays, X-rays and visible light, searching for powerful explosions in the universe. Now, a team of researchers led by Vito Sguera of the Institute of Space Astrophysics and Cosmic Physics of Bologna, Italy, has analyzed archival INTEGRAL data, looking for interesting FXTs in the galactic plane, still undetected by other X-ray telescopes. "We report on the analysis of archival INTEGRAL data pertaining to observations of specific regions of the galactic plane with the aim of finding new FXTs. As result, we report on the discovery of two new such sources which have not been previously detected by any other X-ray telescope," the paper reads. The newly found FXTs were designated IGR J03346+4414 and IGR J20344+3913. Both sources showcase a remarkable hard X-ray activity above 20 keV, in term of duration, peak-flux and dynamic range. The duration of IGR J03346+4414 is only 15 minutes and it exhibits a fast rise, lasting about three minutes, followed by a slower decay. IGR J20344+3913 lasted 33 minutes and its rise was much slower, as it took the source about 15 minutes to reach its peak activity. "Both are characterized by short and bright outbursts as detected by INTEGRAL," the astronomers wrote in the paper. Presenting the spectral and temporal characteristics of the two FXTs, the scientists also discuss the possible origin of these sources. According to the paper, the most plausible hypotheses that could explain the nature of the two newly detected violent X-ray events include stellar flares, symbiotic X-ray binaries (SyXBs) and blazars behind the galactic plane. Regardless of the nature of these FXTs, the researchers emphasized that their peculiar characteristics make them very interesting targets for astronomers. They also noted that the discovery could be the first step toward revealing a real panoply of X-ray transients. "It seems plausible that other such sources wait to be discovered, further exploitations of the entire INTEGRAL data archive may yield additional discoveries of this kind of interesting X-ray transients," the team concluded. Although a large population of undetected FXTs could be hidden in our galaxy, it will not be easy to discover and characterize new ones due to the very transitory nature and especially the very low duty cycle of such events. While INTEGRAL proved its efficiency as X-ray source hunter, it will continue its scientific mission only till the end of 2018, raising concerns that no tool could replace it in the near future in its search for FXTs. Explore further: Integral sees the Galactic centre playing hide and seek More information: Discovery of two new Fast X-ray Transients with INTEGRAL: IGR J03346+4414 and IGR J20344+3913, arXiv:1608.08071 [astro-ph.HE] arxiv.org/abs/1608.08071 Abstract We report on the discovery of two Fast X-ray Transients (FXTs) from analysis of archival INTEGRAL data. Both are characterized by a remarkable hard X-ray activity above 20 keV, in term of duration (about 15 and 30 minutes, respectively), peak-flux (about 10^-9 erg cm^-2 s^-1) and dynamic range (about 2400 and 1360, respectively). Swift/XRT follow-up observations failed to detect any quiescent or low level soft X-ray emission from either of the two FXTs, providing an upper limit of the order of a few times 10^-12 erg cm^-2 s^-1. The main spectral and temporal IBIS/ISGRI characteristics are presented and discussed with the aim of infering possible hints on their nature.