1,447 research outputs found

    The difficulty in the decay constants and spectra of DsJD^{*}_{sJ}

    Full text link
    We examine the compatibility in predicted masses and the decay constants of DsJD^{*}_{sJ} mesons in terms of two-quark contents. We find that the results of a specific model, which is governed by heavy quark limit, will encounter a challenge to fit both spectra and decay constants simultaneously.Comment: 4 pages, 1 figure, Revtex4, to appear in Mod. Phys. Lett.

    Decay Constants of Pseudoscalar DD-mesons in Lattice QCD with Domain-Wall Fermion

    Get PDF
    We present the first study of the masses and decay constants of the pseudoscalar D D mesons in two flavors lattice QCD with domain-wall fermion. The gauge ensembles are generated on the 243×4824^3 \times 48 lattice with the extent Ns=16 N_s = 16 in the fifth dimension, and the plaquette gauge action at β=6.10 \beta = 6.10 , for three sea-quark masses with corresponding pion masses in the range 260475260-475 MeV. We compute the point-to-point quark propagators, and measure the time-correlation functions of the pseudoscalar and vector mesons. The inverse lattice spacing is determined by the Wilson flow, while the strange and the charm quark masses by the masses of the vector mesons ϕ(1020) \phi(1020) and J/ψ(3097) J/\psi(3097) respectively. Using heavy meson chiral perturbation theory (HMChPT) to extrapolate to the physical pion mass, we obtain fD=202.3(2.2)(2.6) f_D = 202.3(2.2)(2.6) MeV and fDs=258.7(1.1)(2.9) f_{D_s} = 258.7(1.1)(2.9) MeV.Comment: 15 pages, 3 figures. v2: the statistics of ensemble (A) with m_sea = 0.005 has been increased, more details on the systematic error, to appear in Phys. Lett.

    Unraveling implicit human behavioral effects on dynamic characteristics of Covid-19 daily infection rates in Taiwan

    Full text link
    We study Covid-19 spreading dynamics underlying 84 curves of daily Covid-19 infection rates pertaining to 84 districts belonging to the largest seven cities in Taiwan during her pristine surge period. Our computational developments begin with selecting and extracting 18 features from each smoothed district-specific curve. This step of computing effort allows unstructured data to be converted into structured data, with which we then demonstrate asymmetric growth and decline dynamics among all involved curves. Specifically, based on Theoretical Information measurements of conditional entropy and mutual information, we compute major factors of order-1 and order-2 that reveal significant effects on affecting the curves' peak value and curvature at peak, which are two essential features characterizing all the curves. Further, we investigate and demonstrate major factors determining the geographic and social-economic induced behavioral effects by encoding each of these 84 districts with two binary characteristics: North-vs-South and Unban-vs-suburban. Furthermore, based on this data-driven knowledge on the district scale, we go on to study fine-scale behavioral effects on infectious disease spreading through similarity among 96 age-group-specific curves of daily infection rate within 12 urban districts of Taipei and 12 suburban districts of New Taipei City, which counts for almost one-quarter of the island nation's total population. We conclude that human living, traveling, and working behaviors do implicitly affect the spreading dynamics of Covid-19 across Taiwan profoundly

    The Switching Message Estimator for Network-Based Motion Control Systems

    Get PDF
    Missing commands from the interpolator caused by the dropout effect of network transmission will cause motion error in motion plants implemented on network-based control systems (NCSs). Dropout data can be properly recovered by applying different message estimators to improve motion contouring accuracy. This study shows that the dropout rate and the distribution of missing commands dominate the motion error, and that more centralized missing commands result in a higher maximum contouring error. The short-window dropout quantity (SDQ) is proposed in this paper to estimate the network quality based on the dropout rate and its distribution of the missing data. Furthermore, according to the condition of missing data based on the SDQ, the switching least-square estimator (LSE) is proposed to compensate for missing motion commands. Simulation and experimental results on the two-axis AC servo motor NCS indicate that motion contouring accuracy is greatly improved by applying the proposed estimator

    The Aqueous Soluble Polyphenolic Fraction of Psidium guajava Leaves Exhibits Potent Anti-Angiogenesis and Anti-Migration Actions on DU145 Cells

    Get PDF
    The aqueous extract of Psidium guajava budding leaves (PE) bears an extremely high content of polyphenolic and isoflavonoids. Whether it could be used as an anti-tumor chemopreventive in view of anti-angiogenesis and anti-migration, we performed the assay methods including the MTT assay to examine the cell viability; the ELISA assay to test the expressions of VEGF, IL-6 and IL-8; the western blot analysis to detect TIMP-2; the gelatinolytic zymography to follow the expression of MMPs; the wound scratch assay to examine the migration capability; and the chicken chorioallantoic membrane assay to detect the suppressive angiogenesis. Results indicated that the IC50 of PE for DU145 cells was ∼0.57 mg ml−1. In addition, PE effectively inhibited the expressions of VEGF, IL-6 and IL-8 cytokines, and MMP-2 and MMP-9, and simultaneously activated TIMP-2 and suppressed the cell migration and the angiogenesis. Conclusively, PE potentially possesses a strong anti-DU145 effect. Thus, clinically it owns the potential to be used as an effective adjuvant anti-cancer chemopreventive

    Lexical Retrieval Hypothesis in Multimodal Context

    Full text link
    Multimodal corpora have become an essential language resource for language science and grounded natural language processing (NLP) systems due to the growing need to understand and interpret human communication across various channels. In this paper, we first present our efforts in building the first Multimodal Corpus for Languages in Taiwan (MultiMoco). Based on the corpus, we conduct a case study investigating the Lexical Retrieval Hypothesis (LRH), specifically examining whether the hand gestures co-occurring with speech constants facilitate lexical retrieval or serve other discourse functions. With detailed annotations on eight parliamentary interpellations in Taiwan Mandarin, we explore the co-occurrence between speech constants and non-verbal features (i.e., head movement, face movement, hand gesture, and function of hand gesture). Our findings suggest that while hand gestures do serve as facilitators for lexical retrieval in some cases, they also serve the purpose of information emphasis. This study highlights the potential of the MultiMoco Corpus to provide an important resource for in-depth analysis and further research in multimodal communication studies

    Exploring Affordance and Situated Meaning in Image Captions: A Multimodal Analysis

    Full text link
    This paper explores the grounding issue regarding multimodal semantic representation from a computational cognitive-linguistic view. We annotate images from the Flickr30k dataset with five perceptual properties: Affordance, Perceptual Salience, Object Number, Gaze Cueing, and Ecological Niche Association (ENA), and examine their association with textual elements in the image captions. Our findings reveal that images with Gibsonian affordance show a higher frequency of captions containing 'holding-verbs' and 'container-nouns' compared to images displaying telic affordance. Perceptual Salience, Object Number, and ENA are also associated with the choice of linguistic expressions. Our study demonstrates that comprehensive understanding of objects or events requires cognitive attention, semantic nuances in language, and integration across multiple modalities. We highlight the vital importance of situated meaning and affordance grounding in natural language understanding, with the potential to advance human-like interpretation in various scenarios.Comment: 10 pages, 9 figure
    corecore