469 research outputs found

    WOMD-LiDAR: Raw Sensor Dataset Benchmark for Motion Forecasting

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    Widely adopted motion forecasting datasets substitute the observed sensory inputs with higher-level abstractions such as 3D boxes and polylines. These sparse shapes are inferred through annotating the original scenes with perception systems' predictions. Such intermediate representations tie the quality of the motion forecasting models to the performance of computer vision models. Moreover, the human-designed explicit interfaces between perception and motion forecasting typically pass only a subset of the semantic information present in the original sensory input. To study the effect of these modular approaches, design new paradigms that mitigate these limitations, and accelerate the development of end-to-end motion forecasting models, we augment the Waymo Open Motion Dataset (WOMD) with large-scale, high-quality, diverse LiDAR data for the motion forecasting task. The new augmented dataset WOMD-LiDAR consists of over 100,000 scenes that each spans 20 seconds, consisting of well-synchronized and calibrated high quality LiDAR point clouds captured across a range of urban and suburban geographies (https://waymo.com/open/data/motion/). Compared to Waymo Open Dataset (WOD), WOMD-LiDAR dataset contains 100x more scenes. Furthermore, we integrate the LiDAR data into the motion forecasting model training and provide a strong baseline. Experiments show that the LiDAR data brings improvement in the motion forecasting task. We hope that WOMD-LiDAR will provide new opportunities for boosting end-to-end motion forecasting models.Comment: Dataset website: https://waymo.com/open/data/motion

    Suppress HBV by therapeutic vaccine

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    乙肝预防性疫苗显著减少了乙肝新发感染,但目前全球仍有约2.5亿慢性乙肝感染者,若未得到有效治疗,可能发展为肝癌、肝硬化等终末期肝病并导致死亡。夏宁邵教授团队研究发展了一种新型的B细胞表位嵌合型类病毒颗粒乙肝治疗性疫苗(治疗性蛋白),在多种模型中证实了其对慢性乙肝感染的治疗潜力,为研发治疗慢性乙肝的原创药物提供了新思路。 我校博士后张天英、博士生郭雪染和博士生巫洋涛为该论文共同第一作者,夏宁邵教授、袁权副教授、张军教授为该论文的共同通讯作者。【Abstract】Objective: This study aimed to develop a novel therapeutic vaccine based on a unique B cell epitope and investigate its therapeutic potential against chronic hepatitis B (CHB) in animal models. Methods: A series of peptides and carrier proteins were evaluated in HBV-tolerant mice to obtain an optimized therapeutic molecule. The immunogenicity,therapeutic efficacy and mechanism of the candidate were investigated systematically. Results: Among the HBsAg-aa119-125-containing peptides evaluated in this study, HBsAg-aa113-135 (SEQ13) exhibited the most striking therapeutic effects. A novel immuno-enhanced virus-like particle carrier (CR-T3) derived from the roundleaf bat HBV core antigen (RBHBcAg) was created and used to display SEQ13, forming candidate molecule CR-T3-SEQ13. Multiple copies of SEQ13 displayed on the surface of this particulate antigen promote the induction of a potent anti-HBs antibody response in mice, rabbits and cynomolgus monkeys. Sera and purified polyclonal IgG from the immunized animals neutralized HBV infection in vitro and mediated efficient HBV/HBsAg clearance in the mice. CR-T3-SEQ13-based vaccination induced long-term suppression of HBsAg and HBV DNA in HBV transgenic mice and eradicated the virus completely in hydrodynamic-based HBV carrier mice. The suppressive effects on HBsAg were strongly correlated with the anti-HBs level after vaccination, suggesting that the main mechanism of CR-T3-SEQ13 vaccination therapy was the induction of a SEQ13-specific antibody response that mediated HBV/HBsAg clearance. Conclusions: The novel particulate protein CR-T3-SEQ13 suppressed HBsAg effectively through induction of a humoral immune response in HBV-tolerant mice. This B cell epitope-based therapeutic vaccine may provide a novel immunotherapeutic agent against chronic HBV infection in humans.This work was supported by the National Scientific and Technological Major project (2017ZX10202203-001), the National Natural Science Foundation of China (31730029, 81672023, 81871316 and 81702006) and the Xiamen University President Fund Project (20720160063). 该研究获得了“艾滋病和病毒性肝炎等重大传染病防治”科技重大专项、国家自然科学基金等资助

    Review on Superconducting Materials

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    Short review of the topical comprehension of the superconductor materials classes Cuprate High-Temperature Superconductors, other oxide superconductors, Iron-based Superconductors, Heavy-Fermion Superconductors, Nitride Superconductors, Organic and other Carbon-based Superconductors and Boride and Borocarbide Superconductors, featuring their present theoretical understanding and their aspects with respect to technical applications.Comment: A previous version of this article has been published in \" Applied Superconductivity: Handbook on Devices and Applications \", Wiley-VCH ISBN: 978-3-527-41209-9. The new extended and updated version will be published in \" Encyclopedia of Applied Physics \", Wiley-VC

    Synthesis and catalysis of chemically reduced metal–metalloid amorphous alloys

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    This is the published version. Copyright 2012 Royal Society of ChemistryAmorphous alloys structurally deviate from crystalline materials in that they possess unique short-range ordered and long-range disordered atomic arrangement. They are important catalytic materials due to their unique chemical and structural properties including broadly adjustable composition, structural homogeneity, and high concentration of coordinatively unsaturated sites. As chemically reduced metal–metalloid amorphous alloys exhibit excellent catalytic performance in applications such as efficient chemical production, energy conversion, and environmental remediation, there is an intense surge in interest in using them as catalytic materials. This critical review summarizes the progress in the study of the metal–metalloid amorphous alloy catalysts, mainly in recent decades, with special focus on their synthetic strategies and catalytic applications in petrochemical, fine chemical, energy, and environmental relevant reactions. The review is intended to be a valuable resource to researchers interested in these exciting catalytic materials. We concluded the review with some perspectives on the challenges and opportunities about the future developments of metal–metalloid amorphous alloy catalysts

    Study of the doubly Cabibbo-suppressed decays Ds+K+K+πD^+_s\to K^+K^+\pi^- and Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0

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    Based on 7.33 fb1^{-1} of e+ee^+e^- collision data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, the experimental studies of the doubly Cabibbo-suppressed decays Ds+K+K+πD^+_s\to K^+K^+\pi^- and Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0 are reported. We determine the absolute branching fraction of Ds+K+K+πD^+_s\to K^+K^+\pi^- to be (1.230.25+0.28(stat)±0.06(syst){1.23^{+0.28}_{-0.25}}({\rm stat})\pm0.06({\rm syst})) ×104\times 10^{-4}. No significant signal of Ds+K+K+ππ0D^+_s\to K^+K^+\pi^-\pi^0 is observed and the upper limit on its decay branching fraction at 90\% confidence level is set to be 1.7×1041.7\times10^{-4}.Comment: 10 pages, 4 figures, 4 table

    Updated measurements of the M1 transition ψ(3686)γηc(2S)\psi(3686) \to \gamma \eta_{c}(2S) with ηc(2S)KKˉπ\eta_{c}(2S) \to K \bar{K} \pi

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    Based on a data sample of (27.08±0.14)×108 ψ(3686)(27.08 \pm 0.14 ) \times 10^8~\psi(3686) events collected with the BESIII detector at the BEPCII collider, the M1 transition ψ(3686)γηc(2S)\psi(3686) \to \gamma \eta_{c}(2S) with ηc(2S)KKˉπ\eta_{c}(2S) \to K\bar{K}\pi is studied, where KKˉπK\bar{K}\pi is K+Kπ0K^{+} K^{-} \pi^{0} or KS0K±πK_{S}^{0}K^{\pm}\pi^{\mp}. The mass and width of the ηc(2S)\eta_{c}(2S) are measured to be (3637.8±0.8(stat)±0.2(syst))(3637.8 \pm 0.8 (\rm {stat}) \pm 0.2 (\rm {syst})) MeV/c2c^{2} and (10.5±1.7(stat)±3.5(syst))(10.5 \pm 1.7 (\rm {stat}) \pm 3.5 (\rm {syst})) MeV, respectively. The product branching fraction B(ψ(3686)γηc(2S))×B(ηc(2S)KKˉπ)\mathcal{B}\left(\psi(3686) \rightarrow \gamma \eta_{c}(2 S)\right) \times \mathcal{B}(\eta_{c}(2 S) \rightarrow K \bar{K} \pi) is determined to be (0.97±0.06(stat)±0.09(syst))×105(0.97 \pm 0.06 (\rm {stat}) \pm 0.09 (\rm {syst})) \times 10^{-5}. Using BR(ηc(2S)KKˉπ)=(1.860.49+0.68)%\mathcal{BR}(\eta_{c}(2S)\to K\bar{K}\pi)=(1.86^{+0.68}_{-0.49})\%, we obtain the branching fraction of the radiative transition to be BR(ψ(3686)γηc(2S))=(5.2±0.3(stat)±0.5(syst)1.4+1.9(extr))×104\mathcal{BR}(\psi(3686) \to \gamma \eta_{c}(2S)) = (5.2 \pm 0.3 (\rm {stat}) \pm 0.5 (\rm {syst}) ^{+1.9}_{-1.4} (extr)) \times 10^{-4}, where the third uncertainty is due to the quoted BR(ηc(2S)KKˉπ)\mathcal{BR}(\eta_{c}(2S) \to K\bar{K}\pi)

    Study of η(1405)/η(1475)\eta(1405)/\eta(1475) in J/ψγKS0KS0π0J/\psi\to\gamma K^{0}_{S} K^{0}_{S}\pi^{0} decay

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    Using a sample of (10.09±0.04)×109(10.09\pm0.04)\times10^{9} J/ψJ/\psi decays collected with the BESIII detector, partial wave analyses of the decay J/ψγKS0KS0π0J/\psi\to\gamma K^{0}_{S} K^{0}_{S}\pi^{0} are performed within the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass region below 1.6 GeV/c2{\textrm{GeV}/c^2}. The covariant tensor amplitude method is used in both mass independent and mass dependent approaches. Both analysis approaches exhibit dominant pseudoscalar and axial vector components, and show good consistency for the other individual components. Furthermore, the mass dependent analysis reveals that the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass spectrum for the pseudoscalar component can be well described with two isoscalar resonant states, i.e.{\it i.e.}, the η(1405)\eta(1405) with a mass of 1391.7±0.70.3+11.31391.7\pm0.7_{-0.3}^{+11.3} MeV/c2\textrm{MeV}/c^2 and a width of 60.8±1.212.0+5.560.8\pm1.2_{-12.0}^{+5.5} MeV\textrm{MeV}, and the η(1475)\eta(1475) with a mass of 1507.6±1.632.2+15.51507.6\pm1.6_{-32.2}^{+15.5} MeV/c2\textrm{MeV}/c^2 and a width of 115.8±2.410.9+14.8115.8\pm2.4_{-10.9}^{+14.8} MeV\textrm{MeV}. The first and second uncertainties are statistical and systematic, respectively. Alternate models for the pseudoscalar component are also tested, but the description of the KS0KS0π0K^{0}_{S} K^{0}_{S}\pi^{0} invariant mass spectrum deteriorates significantly.Comment: 20 pages, 6 figures, 6 table

    Search for hidden-charm tetraquark with strangeness in e+eK+DsD0+c.c.e^{+}e^{-}\rightarrow K^+ D_{s}^{*-} D^{*0}+c.c.

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    We report a search for a heavier partner of the recently observed Zcs(3985)Z_{cs}(3985)^{-} state, denoted as ZcsZ_{cs}^{\prime -}, in the process e+eK+DsD0+c.c.e^{+} e^{-}\rightarrow K^{+}D_{s}^{*-}D^{* 0}+c.c., based on e+ee^+e^- collision data collected at the center-of-mass energies of s=4.661\sqrt{s}=4.661, 4.682 and 4.699 GeV with the BESIII detector. The ZcsZ_{cs}^{\prime -} is of interest as it is expected to be a candidate for a hidden-charm and open-strange tetraquark. A partial-reconstruction technique is used to isolate K+K^+ recoil-mass spectra, which are probed for a potential contribution from ZcsDsD0Z_{cs}^{\prime -}\to D_{s}^{*-}D^{* 0} (c.c.c.c.). We find an excess of ZcsDsD0Z_{cs}^{\prime -}\rightarrow D_{s}^{*-}D^{*0} (c.c.c.c.) candidates with a significance of 2.9σ2.9\sigma, after considering systematic uncertainties, at a mass of (4123.5±0.7stat.±1.1syst.)MeV/c2(4123.5 \pm 0.7_{\mathrm{stat.}} \pm 1.1_{\mathrm{syst.}}) \mathrm{MeV}/c^{2}. As the data set is limited in size, the upper limits are evaluated at the 90% confidence level on the product of the Born cross section and the branching fraction of ZcsDsD0Z_{cs}^{\prime-}\rightarrow D_{s}^{*-}D^{* 0}, σBornB\sigma^{\rm Born}\cdot\mathcal{B} at the three energy points, under different assumptions of the ZcsZ_{cs}^{\prime -} mass from 4.120 to 4.140 MeV and of the width from 10 to 50 MeV. Under various mass and width assumptions, the upper limits of σBornB\sigma^{\rm Born}\cdot\mathcal{B} are found to lie in the range of 262\sim6, 373\sim7 and 363\sim6 pb at s=4.661\sqrt{s}=4.661, 4.682 and 4.699 GeV, respectively. The larger data samples that will be collected in the coming years will allow a clearer picture to emerge concerning the existence and nature of the ZcsZ_{cs}^{\prime -} state.Comment: 17 pages, 7 figure
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