No abstract

Attention has become more attractive in person reidentification (ReID) as it is capable of biasing the allocation of available resources towards the most informative parts of an input signal. However, state-of-the-art works concentrate only on coarse or first-order attention design, e.g. spatial and channels attention, while rarely exploring higher-order attention mechanism. We take a step towards addressing this problem. In this paper, we first propose the High-Order Attention (HOA) module to model and utilize the complex and high-order statistics information in attention mechanism, so as to capture the subtle differences among pedestrians and to produce the discriminative attention proposals. Then, rethinking person ReID as a zero-shot learning problem, we propose the Mixed High-Order Attention Network (MHN) to further enhance the discrimination and richness of attention knowledge in an explicit manner. Extensive experiments have been conducted to validate the superiority of our MHN for person ReID over a wide variety of state-of-the-art methods on three large-scale datasets, including Market-1501, DukeMTMC-ReID and CUHK03-NP. Code is available at

Purpose This study was conducted to explore the clinical value of noninvasive assessment of bedside ultrasound in the diagnosis of lung lesions of Coronavirus Disease-19. Methods In this retrospective study, 30 patients with Coronavirus Disease-19 admitted to our hospital from January 18 to February 5, 2020, were selected as the research subjects. All cases were examined by lung ultrasound and CT. Lung lesions were reviewed by blinded observers, with imaging scores being used to analyze the ultrasound findings of lung lesions in patients with Coronavirus Disease-19 and with chest CT being used as the reference standard. The clinical value of ultrasound in the noninvasive assessment of lung lesions was evaluated. Results Lung ultrasound signs in patients with Coronavirus Disease-19 were mainly manifested as interstitial pulmonary edema (90.0 %, 27/30) and pulmonary consolidations (20.0 %, 6/30). The lung lesions were mainly distributed in the subpleural and peripheral pulmonary zones. The lower lobe and the dorsal region had a greater tendency to be involved. There was moderate agreement (Kappa = 0.529) between the noninvasive assessment of bedside ultrasound for lung lesions in patients with Coronavirus Disease-19 and CT. The ultrasound scores to evaluate mild, moderate and severe lung lesions exhibited sensitivity of 68.8 % (11/16), 77.8 % (7/9), 100.0 % (2/2), specificity of 85.7 % (12/14), 76.2 % (16/21), 92.9 % (26/28), and diagnostic accuracy of 76.7 % (23/30), 76.7 % (23/30), 93.3 % (28/30), respectively. The follow-up dynamic ultrasound examination showed that the condition of all patients worsened gradually, with the ultrasound scores of lung lesions increasing to varying degrees. Conclusion Though the diagnostic efficacy of bedside ultrasound is relatively low for mild to moderate patients, it is high for severe patients. Bedside ultrasound has important clinical significance for noninvasive assessment and dynamic observation of lung lesions in patients with Coronavirus Disease-19, which is worth further consideration.

Insightful understanding of how interfacial structures and properties affect catalytic processes is one of the most challenging issues in heterogeneous catalysis. Here, the essential roles of Pt-Au and Pt-oxide-Au interfaces on the activation of H and the hydrogenation of para-nitrothiophenol (pNTP) were studied at molecular level by in situ surface-enhanced Raman spectroscopy (SERS) and shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). Pt-Au and Pt-oxide-Au interfaces were fabricated through the synthesis of Pt-on-Au and Pt-on-SHINs nanocomposites. Direct spectroscopic evidence demonstrates that the atomic hydrogen species generated on the Pt nanocatalysts can spill over from Pt to Au via the Pt-Au and Pt-TiO-Au interfaces, but would be blocked at the Pt-SiO-Au interfaces, leading to the different reaction pathways and product selectivity on Pt-on-Au and Pt-on-SHINs nanocomposites. Such findings have also been verified by the density functional theory calculation. In addition, it is found that nanocatalysts assembled on pinhole-free shell-isolated nanoparticles (Pt-on-pinhole-free-SHINs) can override the influence of the Au core on the reaction and can be applied as promising platforms for the in situ study of heterogeneous catalysis. This work offers a concrete example of how SERS/SHINERS elucidate details about in situ reaction and helps to dig out the fundamental role of interfaces in catalysis.