417 research outputs found

    On the evaluation of some three-body variational integrals

    Get PDF
    Stable recursive relations are presented for the numerical computation of the integrals ∫dr1dr2r1l−1r2m−1r12n−1exp⁥{−αr1−ÎČr2−γr12}\int d{\bf r}_1 d{\bf r}_2 r_1^{l-1} r_2^{m-1} r_{12}^{n-1} \exp{\{-\alpha r_1 -\beta r_2 -\gamma r_{12}\}} (ll, mm and nn integer, α\alpha, ÎČ\beta and Îł\gamma real) when the indices ll, mm or nn are negative. Useful formulas are given for particular values of the parameters α\alpha, ÎČ\beta and Îł\gamma.Comment: 12 pages, 1 figure (PS) and 3 tables. Old figures 2 and 3 replaced by Tables I and III. A further table added. Paper enlarged giving some tips on the convergence of quadrature

    Characterizing and Detecting Hateful Users on Twitter

    Full text link
    Most current approaches to characterize and detect hate speech focus on \textit{content} posted in Online Social Networks. They face shortcomings to collect and annotate hateful speech due to the incompleteness and noisiness of OSN text and the subjectivity of hate speech. These limitations are often aided with constraints that oversimplify the problem, such as considering only tweets containing hate-related words. In this work we partially address these issues by shifting the focus towards \textit{users}. We develop and employ a robust methodology to collect and annotate hateful users which does not depend directly on lexicon and where the users are annotated given their entire profile. This results in a sample of Twitter's retweet graph containing 100,386100,386 users, out of which 4,9724,972 were annotated. We also collect the users who were banned in the three months that followed the data collection. We show that hateful users differ from normal ones in terms of their activity patterns, word usage and as well as network structure. We obtain similar results comparing the neighbors of hateful vs. neighbors of normal users and also suspended users vs. active users, increasing the robustness of our analysis. We observe that hateful users are densely connected, and thus formulate the hate speech detection problem as a task of semi-supervised learning over a graph, exploiting the network of connections on Twitter. We find that a node embedding algorithm, which exploits the graph structure, outperforms content-based approaches for the detection of both hateful (95%95\% AUC vs 88%88\% AUC) and suspended users (93%93\% AUC vs 88%88\% AUC). Altogether, we present a user-centric view of hate speech, paving the way for better detection and understanding of this relevant and challenging issue.Comment: This is an extended version of the homonymous short paper to be presented at ICWSM-18. arXiv admin note: text overlap with arXiv:1801.0031

    The HIF1A Functional Genetic Polymorphism at Locus +1772 Associates with Progression to Metastatic Prostate Cancer and Refractoriness to Hormonal Castration

    Get PDF
    The hypoxia inducible factor 1 alpha (HIF1a) is a key regulator of tumour cell response to hypoxia, orchestrating mechanisms known to be involved in cancer aggressiveness and metastatic behaviour. In this study we sought to evaluate the association of a functional genetic polymorphism in HIF1A with overall and metastatic prostate cancer (PCa) risk and with response to androgen deprivation therapy (ADT). The HIF1A +1772 C>T (rs11549465) polymorphism was genotyped, using DNA isolated from peripheral blood, in 1490 male subjects (754 with prostate cancer and 736 controls cancer-free) through Real-Time PCR. A nested group of cancer patients who were eligible for androgen deprivation therapy was followed up. Univariate and multivariate models were used to analyse the response to hormonal treatment and the risk for developing distant metastasis. Age-adjusted odds ratios were calculated to evaluate prostate cancer risk. Our results showed that patients under ADT carrying the HIF1A +1772 T-allele have increased risk for developing distant metastasis (OR, 2.0; 95%CI, 1.1-3.9) and an independent 6-fold increased risk for resistance to ADT after multivariate analysis (OR, 6.0; 95%CI, 2.2-16.8). This polymorphism was not associated with increased risk for being diagnosed with prostate cancer (OR, 0.9; 95%CI, 0.7-1.2). The HIF1A +1772 genetic polymorphism predicts a more aggressive prostate cancer behaviour, supporting the involvement of HIF1a in prostate cancer biological progression and ADT resistance. Molecular profiles using hypoxia markers may help predict clinically relevant prostate cancer and response to ADT

    Current deformation in Central Afar and triple junction kinematics deduced from GPS and InSAR measurements

    Get PDF
    Kinematics of divergent boundaries and Rift-Rift-Rift junctions are classically studied using long-term geodetic observations. Since significant magma-related displacements are expected, short-term deformation provides important constraints on the crustal mechanisms involved both in active rifting and in transfer of extensional deformation between spreading axes. Using InSAR and GPS data, we analyse the surface deformation in the whole Central Afar region in detail, focusing on both the extensional deformation across the Quaternary magmato-tectonic rift segments, and on the zones of deformation transfer between active segments and spreading axes. The largest deformation occurs across the two recently activated Asal-Ghoubbet (AG) and Manda Hararo-Dabbahu (MH-D) magmato-tectonic segments with very high strain rates, whereas the other Quaternary active segments do not concentrate any large strain, suggesting that these rifts are either sealed during interdyking periods or not mature enough to remain a plate boundary. Outside of these segments, the GPS horizontal velocity field shows a regular gradient following a clockwise rotation of the displacements from the Southeast to the East of Afar, with respect to Nubia. Very few shallow creeping structures can be identified as well in the InSAR data. However, using these data together with the strain rate tensor and the rotations rates deduced from GPS baselines, the present-day strain field over Central Afar is consistent with the main tectonic structures, and therefore with the long-term deformation. We investigate the current kinematics of the triple junction included in our GPS data set by building simple block models. The deformation in Central Afar can be described by adding a central microblock evolving separately from the three surrounding plates. In this model, the northern block boundary corresponds to a deep EW-trending trans-tensional dislocation, locked from the surface to 10–13 km and joining at depth the active spreading axes of the Red Sea and the Aden Ridge, from AG to MH-D rift segments. Over the long-term, this plate configuration could explain the presence of the en-Ă©chelon magmatic basins and subrifts. However, the transient behaviour of the spreading axes implies that the deformation in Central Afar evolves depending on the availability of magma supply within the well-established segments

    Gemcitabine as a Therapeutic Alternative during Shortage of BCG: The CHLC (Hospital S. José) Experience

    Get PDF
    Introdução: Os tumores nĂŁo mĂșsculo invasivos da bexiga devem ser estratificados em grupos de risco de forma a adequar o tratamento apĂłs cirurgia a cada doente. Nos tumores de alto risco deve ser realizada terapĂȘutica adjuvante com bacilo de Calmette-GuĂ©rin (BCG) intravesical durante 1 a 3 anos. TĂȘm sido reportadas roturas de stock de BCG intravesical, tendo sido o Centro Hospitalar de Lisboa Central (CHLC) afectado nos anos 2014 e 2015, o que obrigou a uma reformulação no tratamento dos doentes que tinham indicação para realização desta terapĂȘutica. A gencitabina poderĂĄ ser uma alternativa vĂĄlida, dado que alguns estudos mostram que poderĂĄ ter um papel nos doentes de risco intermĂ©dio, como alternativa Ă  mitomicina C, e nos de alto risco, refractĂĄrios Ă  BCG, com um perfil de toxicidade mais favorĂĄvel. Material e MĂ©todos: Trata-se de um estudo retrospectivo descritivo que incluiu doentes com tumores da bexiga nĂŁo musculo-invasivos de alto risco, com inĂ­cio da doença em 2013/2014, afectados pelo perĂ­odo de escassez de BCG no Centro Hospitalar. Resultados: No CHLC, 11 doentes com tumores de alto risco foram submetidos a terapĂȘutica com gencitabina, apenas dois exclusivamente, os restantes sequencialmente com BCG. Apenas dois doentes, tratados com BCG e gencitabina, apresentaram recidiva tumoral. No entanto, um nĂșmero significativo (6 em 11) sofreram efeitos adversos, dois dos quais que levaram Ă  interrupção da terapĂȘutica. ConclusĂŁo: Aparentemente, a gencitabina foi uma boa alternativa de terapĂȘutica adjuvante na ausĂȘncia do tratamento gold standard (BCG), dada a existĂȘncia de baixo nĂșmero de recidivais tumorais, apesar do elevado nĂșmero de efeitos adversos reportados.info:eu-repo/semantics/publishedVersio

    GPS network monitor the Western Alps deformation over a five year period: 1993-1998

    Get PDF
    GPS surveys in the Western Alps, performed in the time span 1993-2003, estimated the current crustal deformation of this area.Published63-763.2. Tettonica attivaJCR Journalreserve
    • 

    corecore