694 research outputs found

    Predictors of mortality in patients with Eisenmenger syndrome and admission to the lung transplantation waiting list

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    Background. Patients with Eisenmenger Syndrome (ES) have very severe irreversible pulmonary hypertension but the criteria for admitting such patients to a lung transplantation waiting list (LTWL) is not clear. Indeed it has been demonstrated that the natural survival of patients with ES is better than the survival achieved through lung transplantation: it follows that no guidelines are available for these patients' admission to an LTWL. The aim of our study was to identify possible predictors of mortality in ES patients in order to reserve admission to the LTWL solely for those patients who would otherwise have the lowest probability of survival. Methods. Since 1991, 57 patients with ES from our rehabilitative centre were admitted to the LTWL of the Division of Cardiac Surgery at San Matteo Hospital, University of Pavia. At the time of the retrospective analysis, patients were divided into a group of non-transplanted survivors (27 patients - 47% of the total) and a group who had died prior to transplantation (16 patients - 28% of the total). The 14 transplanted patients (25% of the total) were not considered in the statistical analysis, considering transplantation as an "external event". Unpaired t tests were used to compare the following factors in the survivors and in those who died: sex, "complexity" of the congenital heart disease underlying the ES, previous cardiac surgery, arterial blood gases, pulmonary function and hemodynamic parameters. Moreover, a stepwise discriminant analysis was performed in order to define a possible set of prognostic factors. Results. PaCO2 was higher in those who subsequently died (36.15±7.42 mmHg) compared with those who survived (32.5±5.33 mmHg), although this difference did not reach a statistical significance (p=0.08). Discriminant analysis defined a model in which a) complexity of the congenital heart disease, b) sex (male) and c) cardiac output were predictive of a higher risk of mortality. Conclusions. This new knowledge can be used in the decision of admission to LTWL in ES patients

    Seroprevalence and incidence of Toxoplasma gondii infection in the Legnano area of Italy

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    ABSTRACTThe decreasing prevalence of anti-Toxoplasma antibodies in Europe has re-opened the question of the appropriateness of serological screening during pregnancy. A study of 3426 pregnant women, resident in the Legnano area of Italy, revealed that the IgG seroprevalence according to ELISA was 21.5%, and that of IgM according to ELISA and enzyme-linked fluorescent assay was 1.2% and 0.9%, respectively. The incidence of infection, estimated on the basis of IgG avidity, was 0.9%. These results confirm a decrease in the prevalence of IgG, but indicate a high incidence of infection, thus suggesting that screening for anti-Toxoplasma antibodies during pregnancy should be maintained

    Non-collaborative Attackers and How and Where to Defend Flawed Security Protocols (Extended Version)

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    Security protocols are often found to be flawed after their deployment. We present an approach that aims at the neutralization or mitigation of the attacks to flawed protocols: it avoids the complete dismissal of the interested protocol and allows honest agents to continue to use it until a corrected version is released. Our approach is based on the knowledge of the network topology, which we model as a graph, and on the consequent possibility of creating an interference to an ongoing attack of a Dolev-Yao attacker, by means of non-collaboration actuated by ad-hoc benign attackers that play the role of network guardians. Such guardians, positioned in strategical points of the network, have the task of monitoring the messages in transit and discovering at runtime, through particular types of inference, whether an attack is ongoing, interrupting the run of the protocol in the positive case. We study not only how but also where we can attempt to defend flawed security protocols: we investigate the different network topologies that make security protocol defense feasible and illustrate our approach by means of concrete examples.Comment: 29 page

    From Display to Labelled Proofs for Tense Logics

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    We introduce an effective translation from proofs in the display calculus to proofs in the labelled calculus in the context of tense logics. We identify the labelled calculus proofs in the image of this translation as those built from labelled sequents whose underlying directed graph possesses certain properties. For the basic normal tense logic Kt, the image is shown to be the set of all proofs in the labelled calculus G3Kt

    Automating Agential Reasoning: Proof-Calculi and Syntactic Decidability for STIT Logics

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    This work provides proof-search algorithms and automated counter-model extraction for a class of STIT logics. With this, we answer an open problem concerning syntactic decision procedures and cut-free calculi for STIT logics. A new class of cut-free complete labelled sequent calculi G3LdmL^m_n, for multi-agent STIT with at most n-many choices, is introduced. We refine the calculi G3LdmL^m_n through the use of propagation rules and demonstrate the admissibility of their structural rules, resulting in auxiliary calculi Ldm^m_nL. In the single-agent case, we show that the refined calculi Ldm^m_nL derive theorems within a restricted class of (forestlike) sequents, allowing us to provide proof-search algorithms that decide single-agent STIT logics. We prove that the proof-search algorithms are correct and terminate

    The X-ray outburst of the Galactic Centre magnetar SGR J1745-2900 during the first 1.5 year

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    In 2013 April a new magnetar, SGR 1745-2900, was discovered as it entered an outburst, at only 2.4 arcsec angular distance from the supermassive black hole at the Centre of the Milky Way, Sagittarius A*. SGR 1745-2900 has a surface dipolar magnetic field of ~ 2x10^{14} G, and it is the neutron star closest to a black hole ever observed. The new source was detected both in the radio and X-ray bands, with a peak X-ray luminosity L_X ~ 5x10^{35} erg s^{-1}. Here we report on the long-term Chandra (25 observations) and XMM-Newton (8 observations) X-ray monitoring campaign of SGR 1745-2900, from the onset of the outburst in April 2013 until September 2014. This unprecedented dataset allows us to refine the timing properties of the source, as well as to study the outburst spectral evolution as a function of time and rotational phase. Our timing analysis confirms the increase in the spin period derivative by a factor of ~2 around June 2013, and reveals that a further increase occurred between 2013 Oct 30 and 2014 Feb 21. We find that the period derivative changed from 6.6x10^{-12} s s^{-1} to 3.3x10^{-11} s s^{-1} in 1.5 yr. On the other hand, this magnetar shows a slow flux decay compared to other magnetars and a rather inefficient surface cooling. In particular, starquake-induced crustal cooling models alone have difficulty in explaining the high luminosity of the source for the first ~200 days of its outburst, and additional heating of the star surface from currents flowing in a twisted magnetic bundle is probably playing an important role in the outburst evolution.Comment: 16 pages, 12 figures; accepted for publication on MNRA

    Searching for small-scale diffuse emission around SGR 1806-20

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    Diffuse radio emission was detected around the soft gamma-ray repeater SGR 1806-20, after its 2004 powerful giant flare. We study the possible extended X-ray emission at small scales around SGR 1806-20, in two observations by the High Resolution Camera Spectrometer (HRC-S) on board of the Chandra X-ray Observatory: in 2005, 115 days after the giant flare, and in 2013, during quiescence. We compare the radial profiles extracted from data images and PSF simulations, carefully considering various issues related with the uncertain calibration of the HRC PSF at sub-arcsecond scales. We do not see statistically significant excesses pointing to an extended emission on scales of arcseconds. As a consequence, SGR 1806-20 is compatible with being point-like in X-rays, months after the giant flare, as well as in quiescence.Comment: Accepted for publication in Journal of High-Energy Astrophysics. 13 pages, 4 figures, 2 table

    Emulation of X-ray Light-Field Cameras

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    X-ray plenoptic cameras acquire multi-view X-ray transmission images in a single exposure (light-field). Their development is challenging: designs have appeared only recently, and they are still affected by important limitations. Concurrently, the lack of available real X-ray light-field data hinders dedicated algorithmic development. Here, we present a physical emulation setup for rapidly exploring the parameter space of both existing and conceptual camera designs. This will assist and accelerate the design of X-ray plenoptic imaging solutions, and provide a tool for generating unlimited real X-ray plenoptic data. We also demonstrate that X-ray light-fields allow for reconstructing sharp spatial structures in three-dimensions (3D) from single-shot data

    Needs, expectations and consequences for the child growing up in a family with a parent with mental illness

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    Parental mental illness is considered one of the strongest risk-factors for development of offspring psychopathology. The lack of pan-European guidelines for empowering children of parents with mental illness led to EU project CAMILLE - Empowerment of Children and Adolescents of Mentally Ill Parents through Training of Professionals working with children and adolescents. The first task in this project, was to analyse needs, expectations and consequences for children, with respect to living with a parent with mental illness. The aim this paper is to report results of these analyses. The qualitative research was conducted in England, Finland, Germany, Italy, Norway, Poland and Scotland (N=96). There were 3 types of focus groups: (1) professionals (doctors, nurses, psychologists, social workers), (2) adult children and partners of a person with mental illness, (3) parents who have experienced mental illness during their parenthood. Framework analysis method was used. Results of the study highlighted that the main consequences for children of parental mental illness were role reversal, emotional and behavioural problems, lack of parent’s attention and stigma. The main needs of these children were emotional support, security and multidisciplinary help. Implications for practice are: (1) professionals working with parents with mental illness should be aware of the specific consequences for the children; (2) to empower children they should focus on them, but not excluding parents from the parental roles; (3) the multi-agency collaboration is necessary; (4) schools should provide counselling and teach staff and students about mental health problems to reduce stigm

    Biological heterogeneity of putative bladder cancer stem-like cell populations from human bladder transitional cell carcinoma samples.

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    Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Emerging evidence has suggested that the capability of a tumor to grow and propagate is dependent on a small subset of cells, the cancer stem-like cells (CSCs) or tumor initiating cells. We report on the isolation and biological characterization of putative bladder CSC populations from primary TCCs. Isolated cells were induced to proliferate in stem cell culture conditions (serum-free medium containing mitogenic growth factors). The proliferating cells formed spheroids (urospheres) and their abilities for extensive proliferation and self-renewal were assayed. Their positivity for several stem cell markers (CD133, Oct-3/4, nestin, and cytokeratins) was also assessed by immunofluorescence tests and they could have the potential to differentiate in the presence of serum. In stem cell culture conditions they gradually showed loss of proliferation, adherence to the substrate, and morphological changes, which might reflect their progressive acquisition of differentiative capacity and loss of self-renewal ability. To evaluate if effective cell selection occurred after isolation, conventional cytogenetic studies on fresh chromosome spreads immediately after isolation and after culture were carried out. In addition, a molecular cytogenetic study by UroVysion assay was carried out on paraffin-embedded tissue sections and on fresh and after culture nuclei preparations. The data collected indicated important karyotype changes and a positive selection for hypo- or near-diploid cells, losing the complexity present in fresh tumors
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