446 research outputs found

    Reversing conditional orderings

    Get PDF
    We analyze some specific aspects concerning conditional orderings and relations among them. To this purpose we define a suitable concept of reversed conditional ordering and prove some related results. In particular we aim to compare the univariate stochastic orderings ≤ st, ≤ hr, and ≤ lr in terms of differences among different notions of conditional orderings. Some applications of our result to the analysis of positive dependence will be detailed. We concentrate attention to the case of a pair of scalar random variables X, Y ​. Suitable extensions to multivariate cases are possible

    Detecting Sarcasm in Multimodal Social Platforms

    Full text link
    Sarcasm is a peculiar form of sentiment expression, where the surface sentiment differs from the implied sentiment. The detection of sarcasm in social media platforms has been applied in the past mainly to textual utterances where lexical indicators (such as interjections and intensifiers), linguistic markers, and contextual information (such as user profiles, or past conversations) were used to detect the sarcastic tone. However, modern social media platforms allow to create multimodal messages where audiovisual content is integrated with the text, making the analysis of a mode in isolation partial. In our work, we first study the relationship between the textual and visual aspects in multimodal posts from three major social media platforms, i.e., Instagram, Tumblr and Twitter, and we run a crowdsourcing task to quantify the extent to which images are perceived as necessary by human annotators. Moreover, we propose two different computational frameworks to detect sarcasm that integrate the textual and visual modalities. The first approach exploits visual semantics trained on an external dataset, and concatenates the semantics features with state-of-the-art textual features. The second method adapts a visual neural network initialized with parameters trained on ImageNet to multimodal sarcastic posts. Results show the positive effect of combining modalities for the detection of sarcasm across platforms and methods.Comment: 10 pages, 3 figures, final version published in the Proceedings of ACM Multimedia 201

    TRAIL Coated Genetically Engineered Immunotherapeutic Nano-Ghosts Vesicles Target Human Melanoma-Avoiding the Need for High Effective Therapeutic Concentration of TRAIL

    Get PDF
    Cancer cell therapy using cytotoxic T lymphocytes (CTL) or mesenchymal stem cells (MSC) possesses hurdles due to the cells, susceptibility to host induced changes. Here, versatile inanimate broadly applicable nanovesicles, termed immunotherapeutic-nano-ghosts (iNGs), are armed with inherent surface-associated targeting and therapeutic capabilities in which the promise and benefits of MSC therapy and T cell immunotherapy are combined into one powerful off-the-shelf approach for treating malignant diseases. To mimic the cytotoxic or immunosuppressive functions of T cells, iNG are produced from MSC that were genetically engineered (GE) or metabolically manipulated to express additional membrane-bound proteins, endowing the NGs derived therefrom with additional surface-associated functions such as tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). iNGs from GE-MSCs (GE-iNGs) show superior TRAIL retention and induce apoptosis in different cancer cell lines in vitro. In vivo studies on a human melanoma model demonstrate that a systemic, three-day frequency, administration of GE-iNGs result in tumor inhibition comparable to a six orders of magnitude higher concentration of soluble TRAIL. The iNGs are therefore a promising nanovesicle platform that can affect tumors in a non-immunogenic manner while avoiding the need for a highly effective therapeutic concentration

    An alternative approach for the dynamics of polarons in one dimension

    Full text link
    We developed a new method based on functional integration to treat the dynamics of polarons in one-dimensional systems. We treat the acoustical and the optical case in an unified manner, showing their differences and similarities. The mobility and diffusion coefficients are calculated in the Markovian approximation in the strong coupling limit.Comment: 57 page

    Does survey respondents' immigrant background affect the measurement and prediction of immigration attitudes ? An illustration in two steps

    Get PDF
    While most survey research on immigration attitudes routinely excludes respondents with an immigrant background, empirical justifications for doing so are rarely provided. Yet it is crucial to examine whether respondents with an immigrant background can be included in the analysis, as excluding them with no further consideration would ignore the opinion of a considerable share of multicultural societies. With multigroup analyses on Swiss data we illustrated how to evaluate whether both the measurement and the prediction of immigration attitudes are invariant across natives and individuals with an immigrant background. The slight revealed differences did not justify the exclusion of respondents with an immigrant background. The paper concludes by discussing ways of addressing these differences in measurement and prediction

    A spinor approach to Walker geometry

    Full text link
    A four-dimensional Walker geometry is a four-dimensional manifold M with a neutral metric g and a parallel distribution of totally null two-planes. This distribution has a natural characterization as a projective spinor field subject to a certain constraint. Spinors therefore provide a natural tool for studying Walker geometry, which we exploit to draw together several themes in recent explicit studies of Walker geometry and in other work of Dunajski (2002) and Plebanski (1975) in which Walker geometry is implicit. In addition to studying local Walker geometry, we address a global question raised by the use of spinors.Comment: 41 pages. Typos which persisted into published version corrected, notably at (2.15

    On the Bergman representative coordinates

    Full text link
    We study the set where the so-called Bergman representative coordinates (or Bergman functions) form an immersion. We provide an estimate of the size of a maximal geodesic ball with respect to the Bergman metric, contained in this set. By concrete examples we show that these estimates are the best possible.Comment: 20 page
    corecore