29 research outputs found

    Syncope in Elderly People: A Threatening Presentation of Pulmonary Embolism: A Case Report

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    age. Its prognosis is largely unpredictable, pending the origin of the sudden loss of consciousness. We report a case of an old woman affected by severe chronic heart failure, who died soon after the development of an episode of syncope, which was eventually attributed to pulmonary embolism. Anticoagulant therapy, promptly instituted, was ineffective. In the differential diagnoses of syncope, pulmonary embolism should always be considered, especially in old patients with risk factors for venous thromboembolism such as a severe heart failure. In patients with high risk of death according to the widely adopted risk stratifications score, aggressive therapy may be considered also in elderly people to prevent unfavourable outcomes

    Improving elevation perception with a tool for image-guided head-related transfer function selection

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    This paper proposes an image-guided HRTF selection procedure that exploits the relation between features of the pinna shape and HRTF notches. Using a 2D image of a subject's pinna, the procedure selects from a database the HRTF set that best fits the anthropometry of that subject. The proposed procedure is designed to be quickly applied and easy to use for a user without previous knowledge on binaural audio technologies. The entire process is evaluated by means of an auditory model for sound localization in the mid-sagittal plane available from previous literature. Using virtual subjects from a HRTF database, a virtual experiment is implemented to assess the vertical localization performance of the database subjects when they are provided with HRTF sets selected by the proposed procedure. Results report a statistically significant improvement in predictions of localization performance for selected HRTFs compared to KEMAR HRTF which is a commercial standard in many binaural audio solutions; moreover, the proposed analysis provides useful indications to refine the perceptually-motivated metrics that guides the selection

    Endothelial dysfunction in patients with spontaneous venous thromboembolism

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    Background and Objectives A high incidence of atherosclerotic lesions and cardiovascular events has been reported in patients with spontaneous venous thromboembolism. Endothelial dysfunction is an early marker of atherosclerosis and has predictive value for ischemic events. We have evaluated endothelial function in patients with a history of spontaneous venous thromboembolism.Design and Methods Patients with a history of symptomatic, objectively confirmed, spontaneous venous thromboembolism were included in a case-control study. Exclusion criteria were any known risk factors for cardiovascular diseases, other conditions associated with endothelial dysfunction, estro-progestinic therapy or pregnancy. Controls were age-(±5 years) and sex-matched subjects with the same exclusion criteria but without previous venous thromboembolism. Endothelial function was evaluated by the non-invasive measurement of flow-mediated vasodilation of the brachial artery and of plasma markers of endothelium activation; platelet activation parameters were also measured.Results Twenty-eight cases (8 females; mean age 59±15 years) and 28 controls (8 females; mean age 58±15) were studied. Flow-mediated vasodilation was 3.5±0.6% in cases (95% CIs: 2.2 to 4.8) and 5.7±0.6% (4.2 to 6.8) in controls (p=0.015). Brachial artery blood flow and hyperemic blood flow did not differ between the two groups. Plasma von Willebrand factor and soluble P-selectin levels were significantly higher in patients with venous thromboembolism, while plasma soluble CD40 ligand and urinary 11-dehydro-TxB2 levels were similar in cases and controls.Interpretation and Conclusions Patients with spontaneous venous thromboembolism have endothelial dysfunction, unlike age- and sex- matched controls. This finding suggests that spontaneous venous thromboembolism may be a condition associated with an enhanced risk of atherosclerosis

    X-ray properties and obscured fraction of AGN in the J1030 Chandra field

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    The 500ks Chandra ACIS-I observation of the field around the z=6.31z=6.31 quasar SDSS J1030+0524 is currently the 5th deepest extragalactic X-ray survey. The rich multi-band coverage of the field allowed for an effective identification and redshift determination of the X-ray source counterparts: to date a catalog of 243 extragalactic X-ray sources with either a spectroscopic or photometric redshift estimate in the range z06z\approx0-6 is available over a 355 arcmin2^2 area. Given its depth and the multi-band information, this catalog is an excellent resource to investigate X-ray spectral properties of distant Active Galactic Nuclei (AGN) and derive the redshift evolution of their obscuration. We performed a thorough X-ray spectral analysis for each object in the sample, measuring its nuclear column density NHN_{\rm H} and intrinsic (de-absorbed) 2-10 keV rest-frame luminosity, L210L_{2-10}. Whenever possible, we also used the presence of the Fe Kα_\alpha emission line to improve the photometric redshift estimates. We measured the fractions of AGN hidden by column densities in excess of 102210^{22} and 102310^{23}cm2^{-2} (f22f_{22} and f23f_{23}, respectively) as a function of L210L_{2-10} and redshift, and corrected for selection effects to recover the intrinsic obscured fractions. At z1.2z\sim 1.2, we found f220.70.8f_{22}\sim0.7-0.8 and f230.50.6f_{23}\sim0.5-0.6, respectively, in broad agreement with the results from other X-ray surveys. No significant variations with X-ray luminosity were found within the limited luminosity range probed by our sample (logL21042.844.3L_{2-10}\sim 42.8-44.3). When focusing on luminous AGN with logL21044L_{2-10}\sim44 to maximize the sample completeness up to large cosmological distances, we did not observe any significant change in f22f_{22} or f23f_{23} over the redshift range z0.83z\sim0.8-3. Nonetheless, the obscured fractions we measure are significantly higher than ...Comment: A&A, in pres

    LBT-MODS spectroscopy of high-redshift candidates in the Chandra J1030 field. A newly discovered z\sim2.8 large scale structure

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    We present the results of a spectroscopic campaign with the Multi-Object Double Spectrograph (MODS) instrument mounted on the Large Binocular Telescope (LBT), aimed at obtaining a spectroscopic redshift for seven Chandra J1030 sources with a photometric redshift >=2.7 and optical magnitude r_AB=[24.5-26.5]. We obtained a spectroscopic redshift for five out of seven targets: all of them have z_spec>=2.5, thus probing the reliability of the Chandra J1030 photometric redshifts. The spectroscopic campaign led to the serendipitous discovery of a z~2.78 large scale structure (LSS) in the J1030 field: the structure contains four X-ray sources (three of which were targeted in the LBT-MODS campaign) and two non-X-ray detected galaxies for which a VLT-MUSE spectrum was already available. The X-ray members of the LSS are hosted in galaxies that are significantly more massive (log(M_*/M_sun)=[10.0-11.1]) than those hosting the two MUSE-detected sources (log(M_*/M_sun)<10). Both observations and simulations show that massive galaxies, and particularly objects having log(M_*/M_sun)>10, are among the best tracers of large scale structures and filaments in the cosmic web. Consequently, our result can explain why X-ray-detected AGN have also been shown to be efficient tracers of large scale structures.Comment: 16 pages, 9 Figures. Accepted for publication in Astronomy and Astrophysic

    The web of the Giant: spectroscopic confirmation of a Large Scale Structure around the z=6.31 quasar SDSS J1030+0524

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    We report on the spectroscopic confirmation of a large scale structure around the luminous, z=6.31 QSO SDSS~J1030+0524, that is powered by a billion solar mass black hole. The structure is populated by at least six members, four Lyman Break Galaxies (LBGs) and two Lyman Alpha Emitters (LAEs). The four LBGs have been identified among a sample of 21 i-band dropouts with z{AB}<25.5 selected up to projected separations of 5 physical Mpc (15 arcmin) from the QSO. Their redshifts have been determined through up to 8hr-long multi-object spectroscopic observations at 8-10m class telescopes. The two LAEs have been identified in a 6hr VLT/MUSE observation centered on the QSO. The redshifts of the six galaxies cover the range 6.129-6.355. Assuming that peculiar velocities are negligible, this range corresponds to radial separations of +/-5 physical Mpc from the QSO, that is comparable to the projected scale of the observed LBG distribution on the sky. We conservatively estimate that this structure is significant at >3.5 sigma level, and that the level of the galaxy overdensity is at least 1.5-2 within the large volume sampled (~780 physical Mpc^3). The spectral properties of the six member galaxies (Lyalpha strength and UV luminosity) are similar to those of field galaxies at similar redshifts. This is the first spectroscopic identification of a galaxy overdensity around a super-massive black hole in the first billion years of the Universe. Our finding lends support to the idea that the most distant and massive black holes form and grow within massive (>10^{12} Msun) dark matter halos in large scale structures, and that the absence of earlier detections of such systems was likely due to observational limitations.Comment: 8 pages including Appendix, 5 figures, accepted as a letter on Astronomy & Astrophysics. v2: minor changes in Table 1 caption and Figs. 2 & 3 label

    Redshift identification of X-ray selected active galactic nuclei in the J1030 field: searching for large-scale structures and high-redshift sources

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    We publicly release the spectroscopic and photometric redshift catalog of the sources detected with Chandra in the field of the zz=6.3 quasar SDSS J1030+0525. This is currently the fifth deepest X-ray field, and reaches a 0.5-2 keV flux limit f0.52f_{\rm 0.5-2}=6×\times1017^{-17} erg s1^{-1} cm2^{-2}. By using two independent methods, we measure a photometric redshift for 243 objects, while 123 (51%) sources also have a spectroscopic redshift, 110 of which coming from an INAF-Large Binocular Telescope (LBT) Strategic Program. We use the spectroscopic redshifts to determine the quality of the photometric ones, and find it in agreement with that of other X-ray surveys which used a similar number of photometric data-points. In particular, we measure a sample normalized median absolute deviation σNMAD\sigma_{NMAD}=1.48||zphotz_{phot}-zspecz_{spec}||/(1+zspecz_{spec})=0.065. We use these new spectroscopic and photometric redshifts to study the properties of the Chandra J1030 field. We observe several peaks in our spectroscopic redshift distribution between zz=0.15 and zz=1.5, and find that the sources in each peak are often distributed across the whole Chandra field of view. This evidence confirms that X-ray selected AGN can efficiently track large-scale structures over physical scales of several Mpc. Finally, we computed the Chandra J1030 z>z>3 number counts: while the spectroscopic completeness at high-redshift of our sample is limited, our results point towards a potential source excess at zz\geq4, which we plan to either confirm or reject in the near future with dedicated spectroscopic campaigns

    The LOFT mission concept: a status update

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    The Large Observatory For x-ray Timing (LOFT) is a mission concept which was proposed to ESA as M3 and M4 candidate in the framework of the Cosmic Vision 2015-2025 program. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument and the uniquely large field of view of its wide field monitor, LOFT will be able to study the behaviour of matter in extreme conditions such as the strong gravitational field in the innermost regions close to black holes and neutron stars and the supra-nuclear densities in the interiors of neutron stars. The science payload is based on a Large Area Detector (LAD, >8m2 effective area, 2-30 keV, 240 eV spectral resolution, 1 degree collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g., GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the current technical and programmatic status of the mission

    An unusual finding of massive pulmonary embolism in a patient during treatment with high-dose ibuprofen

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    Non-steroidal anti-inflammatory drugs have been associated with an increased risk of venous thromboembolism. We report for the first time, the case of a patient who developed massive pulmonary embolism after a long period of treatment with high doses of ibuprofen. A 65-year-old woman was admitted with severe dyspnea while on treatment with high doses of ibuprofen for diffuse spine pain due to arthrosis. A spiral computed tomography showed a massive pulmonary embolism. No other explanation for the thromboembolic disorder was found. She was successfully treated with therapeutic doses of lowmolecular- weight heparin followed by rivaroxaban. Ibuprofen was discontinued and replaced by tramadol. High-dose ibuprofen is likely to have accounted for the life-threatening thromboembolic disorder

    Radial MV networks voltage regulation with distribution management system coordinated controller

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    The connection of a great number of distributed generation (DG) plants may cause a critical voltage regulation problem in actual medium voltage (MV) radial distribution networks. After a synthetic survey of different strategies reported in literature to solve this problem, a proposal for an active management of the distribution system which makes use of an innovative controller that coordinates the on load tap changer (OLTC) action with the regulation of reactive exchanges between DG plants and feeders, is presented. In order to test the effectiveness of the proposed regulation, the distribution management system coordinated controller (DMSCC) is applied to a realistic radial structure distribution network and its behaviour simulated in managing the MV system during its worst foreseeable working conditions
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