2,960 research outputs found

    Intestinal intussusception in an adult caused by helminthic parasitosis

    Get PDF
    Intestinal intussusception is an uncommon acute condition in adults and is most commonly caused by an intestinal tumor mass. Helminthic parasitosis is a widespread infection in Africa, and the load of worms is often high in individuals living in areas with inadequate sanitation. We report a case of intestinal obstruction caused by Ascaris lumbricoides infection, which was complicated by ileo-caecal intussusception and required surgical treatment in a 40-year-old Ugandan woman. This case reinforces the importance of anthelminthic prophylaxis in African rural areas

    Tomography of core-mantle boundary and lowermost mantle coupled by geodynamics

    Get PDF
    We propose an innovative approach to mapping CMB topography from seismic P-wave traveltime inversions: instead of treating mantle velocity and CMB topography as independent parameters, as has been done so far, we account for their coupling by mantle flow, as formulated by Forte & Peltier. This approach rests on the assumption that P data are sufficiently sensitive to thermal heterogeneity, and that compositional heterogeneity, albeit important in localized regions of the mantle (e.g. within the D″ region), is not sufficiently strong to govern the pattern of mantle-wide convection and hence the CMB topography. The resulting tomographic maps of CMB topography are physically sound, and they resolve the known discrepancy between images obtained from classic tomography on the basis of core-reflected and core-refracted seismic phases. Since the coefficients of mantle velocity structure are the only free parameters of the inversion, this joint tomography-geodynamics approach reduces the number of parameters; nevertheless the corresponding mantle models fit the seismic data as well as the purely seismic one

    A horse, a horse, my kingdom for a horse. Saddle thrombosis of carotid bifurcation in acute stroke

    Get PDF
    Background: Saddle thrombosis is less frequently detected in carotid arteries than in peripheral arterial embolism. The clot and the distal vessel patency have to be promptly recognized in these cases, because if the carotid vessel is open distally, chances may arise for successful emergent surgical procedures to remove the thrombus. At conventional static imaging, mobile floating thrombi may be difficult to differentiate from thrombosis on carotid complicated lesions of atherosclerotic origin. High-resolution ultrasound (US), with its unique capability of real-time imaging, adds fundamental data for interpretation of the findings. Methods: Carotid ultrasound has been performed in acute stroke patients with high-resolution probes. Real-time clips are analyzed and imaging is presented. Results: Saddle carotid bifurcation thrombosis of cardiac origin has been identified in 2 patients with acute homolateral ischemic stroke, with prompt successful surgical removal in one case. Moreover, an example of a thrombus attached on the ruptured surface of a complicated atherosclerotic plaque in an acute symptomatic stroke patient that was successfully operated in emergency is presented. Conclusions: Early high-resolution ultrasound with real-time imaging can easily identify peculiar characteristics of carotid vulnerable diseases in acute stroke phase. Different clinical implications result from the early identification of these different conditions, modifying the therapeutical strategies. © 2012 Elsevier GmbH

    Comparação de duas soluções extratoras na resolução de cinco sistemas enzimáticos em folhas jovens de cupuaçuzeiro (Theobroma grandiflorum Schum.).

    Get PDF
    bitstream/item/34527/1/ORIENTAL-CirTec4.pd

    The merger that led to the formation of the Milky Way's inner stellar halo and thick disk

    Get PDF
    The assembly process of our Galaxy can be retrieved using the motions and chemistry of individual stars. Chemo-dynamical studies of the nearby halo have long hinted at the presence of multiple components such as streams, clumps, duality and correlations between the stars' chemical abundances and orbital parameters. More recently, the analysis of two large stellar surveys have revealed the presence of a well-populated chemical elemental abundance sequence, of two distinct sequences in the colour-magnitude diagram, and of a prominent slightly retrograde kinematic structure all in the nearby halo, which may trace an important accretion event experienced by the Galaxy. Here report an analysis of the kinematics, chemistry, age and spatial distribution of stars in a relatively large volume around the Sun that are mainly linked to two major Galactic components, the thick disk and the stellar halo. We demonstrate that the inner halo is dominated by debris from an object which at infall was slightly more massive than the Small Magellanic Cloud, and which we refer to as Gaia-Enceladus. The stars originating in Gaia-Enceladus cover nearly the full sky, their motions reveal the presence of streams and slightly retrograde and elongated trajectories. Hundreds of RR Lyrae stars and thirteen globular clusters following a consistent age-metallicity relation can be associated to Gaia-Enceladus on the basis of their orbits. With an estimated 4:1 mass-ratio, the merger with Gaia-Enceladus must have led to the dynamical heating of the precursor of the Galactic thick disk and therefore contributed to the formation of this component approximately 10 Gyr ago. These findings are in line with simulations of galaxy formation, which predict that the inner stellar halo should be dominated by debris from just a few massive progenitors.Comment: 19 pages, 8 figures. Published in Nature in the issue of Nov. 1st, 2018. This is the authors' version before final edit

    Non invasive analysis of manuscript covers: portable X-ray Fluorescence enlighteningh medieval Jewellery masterpieces

    Get PDF
    AbstractThis paper will present portable X-ray fluorescence (pXRF) analysis applied in situ to three 11th- 12th century manuscripts covers considered as masterpieces of Northern Italy medieval jewellery: Pace di Ariberto (Milano), Liber Evangeliorium of Vercelli and Pace di Chiavenna. These objects show a sumptuous decoration of golden leaves, plates and filigrees, enamels and casted gems. The aim of this research is to obtain information on manufacturing techniques and composition of the artefacts, considering possible analogies and differences that may be useful for art historians’ discussion on manufacture place and artistic connections. XRF analysis was performed in order to determine the composition of the metals and enamels, and quantitative results, obtained using certified standards, undergo data treatment with multivariate analysis. The present paper will present a part of the results obtained on both the metals and glass materials, underlying the potential of pXRF in producing reliable results also when working in non-ideal conditions
    • …
    corecore