578 research outputs found

    Episodic Multi-Task Learning with Heterogeneous Neural Processes

    Full text link
    This paper focuses on the data-insufficiency problem in multi-task learning within an episodic training setup. Specifically, we explore the potential of heterogeneous information across tasks and meta-knowledge among episodes to effectively tackle each task with limited data. Existing meta-learning methods often fail to take advantage of crucial heterogeneous information in a single episode, while multi-task learning models neglect reusing experience from earlier episodes. To address the problem of insufficient data, we develop Heterogeneous Neural Processes (HNPs) for the episodic multi-task setup. Within the framework of hierarchical Bayes, HNPs effectively capitalize on prior experiences as meta-knowledge and capture task-relatedness among heterogeneous tasks, mitigating data-insufficiency. Meanwhile, transformer-structured inference modules are designed to enable efficient inferences toward meta-knowledge and task-relatedness. In this way, HNPs can learn more powerful functional priors for adapting to novel heterogeneous tasks in each meta-test episode. Experimental results show the superior performance of the proposed HNPs over typical baselines, and ablation studies verify the effectiveness of the designed inference modules.Comment: 28 pages, spotlight of NeurIPS 202

    Light absorption properties of brown carbon over the southeastern Tibetan Plateau

    Get PDF
    We present a study of the light-absorbing properties of water-soluble brown carbon (WS-BrC) and methanolsoluble brown carbon (MeS-BrC) at a remote site (Lulang, 3326 m above sea level) in the southeastern Tibetan Plateau during the period 2015-2016. The light absorption coefficients at 365 nm (b(abs365)) of WS-BrC and MeS-BrC were the highest during winter and the lowest during monsoon season. MeS-BrC absorbs about 1.5 times higher at 365 nm compared to WS-BrC. The absorption at 550 nm appears lower compared to that of 365 nm for WS-BrC and MeS-BrC, respectively. Higher average value of the absorption Angstrom exponent (AAE, 365-550 nm) was obtained for MeS-BrC (8.2) than that for WS-BrC (6.9). The values of the mass absorption cross section at 365 nm (MAC(365)) indicated that BrC in winter absorbs UV-visible light more efficiently than in monsoon. The results confirm the importance of BrC in contributing to light-absorbing aerosols in this region. The understanding of the light absorption properties of BrC is of great importance, especially in modeling studies for the climate effects and transport of BrC in the Tibetan Plateau. (c) 2017 Elsevier B.V. All rights reserved

    Simultaneous Ni Doping at Atom Scale in Ceria and Assembling into Well-Defined Lotuslike Structure for Enhanced Catalytic Performance

    Get PDF
    Oxide materials with redox capability have attracted worldwide attentions in many applications. Introducing defects into crystal lattice is an effective method to modify and optimize redox capability of oxides as well as their catalytic performance. However, the relationship between intrinsic characteristics of defects and properties of oxides has been rarely reported. Herein, we report a facile strategy to introduce defects by doping a small amount of Ni atoms (∼1.8 at. %) into ceria lattice at atomic level through the effect of microstructure of crystal on the redox property of ceria. Amazingly, a small amount of single Ni atom-doped ceria has formed a homogeneous solid solution with uniform lotuslike morphology. It performs an outstanding catalytic performance of a reduced T50 of CO oxidation at 230 °C, which is 135 °C lower than that of pure CeO2 (365 °C). This is largely attributed to defects such as lattice distortion, crystal defects and elastic strain induced by Ni dopants. The DFT calculation has revealed that the electron density distribution of oxygen ions near Ni dopant, the reduced formation energy of oxygen vacancy originated from local chemical effect caused by local distortion after Ni doping. These differences have a great effect on increasing the concentration of oxygen vacancies and enhancing the migration of lattice oxygen from bulk to a surface which is closely related to optimized redox properties. As a result, oxygen storage capacity and the associated catalytic reactivity has been largely increased. We have clearly demonstrated the change of crystal lattice and the charge distribution effectively modify its chemical and physical properties at the atomic scale

    Elasticity evaluation of the plantar fascia: A shear wave elastography study involving 33 early-stage plantar fasciopathy subjects

    Get PDF
    Background: Plantar fasciopathy, the most common foot condition seen in elderly and athletic populations, can be diagnosed and differentially diagnosed with imaging modalities such as ultrasound shear wave elastography (SWE). However, standard guidelines for ultrasound elastography of the plantar fascia are lacking. The purpose of this study was to determine the impact of the region of interest (ROI) on the evaluation of the plantar fascia elasticity and confirm the screening accuracy of SWE in the early-stage of plantar fasciopathy.Methods: This was an observational case‒control study involving 50 feet of 33 early-stage plantar fasciopathy subjects (the plantar fasciopathy group) and 96 asymptomatic feet of 48 healthy volunteers (the non-pain group). Clinical information, including age, gender, height, weight, visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Scale score (AOFAS), and the symptom duration, were recorded. All participants underwent both conventional ultrasound and SWE evaluation. The plantar fascia elastic parameters included SWEsingle-point, calculated with a single-point ROI set at the greatest thickness of the plantar fascia, and SWEmulti-point, calculated by multipoint ROIs set continuously from the origin at the calcaneus to about 2 cm from the calcaneal origin.Results: The plantar fasciopathy group presented a higher VAS score (median [IQR), 4.00 (3.00) vs. 0.00 (0.00), p < 0.001] and lower AOFAS score [median (IQR), 79.50 (3.00) vs. 100.00 (10.00), p < 0.001] than the non-pain group. The median plantar fascia thickness of the plantar fasciopathy group was significantly greater than that of the non-pain group [median (IQR), 3.95 (1.37) mm vs 2.40 (0.60) mm, p < 0.001]. Abnormal ultrasound features, including echogenicity, border irregularities, and blood flow signals, were more prominent in the plantar fasciopathy group than in the non-pain group (29% vs. 0%, p < 0.001; 26% vs. 1%, p < 0.001; 12% vs. 0%, p < 0.001, respectively). Quantitative analysis of the plantar fascia elasticity revealed that the difference between the value of SWEsingle-point and SWEmultipoint was significant [median (IQR), 65.76 (58.58) vs. 57.42 (35.52) kPa, p = 0.02). There was a moderate and significant correlation between the value of SWEsingle-point and heel pain. However, there was no correlation between the value of SWEmultipoint and heel pain. Finally, we utilized the results of SWEsingle-point as the best elastic parameter reflecting clinical heel pain and found that SWEsingle-point could provide additional value in screening early-stage plantar fasciopathy, with an increase in sensitivity from 76% to 92% over conventional ultrasound alone. Additionally, compared with conventional ultrasound and SWE, the use of both improved the accuracy of screening for plantar fasciopathy. Although there were no significant differences in the negative predictive value of conventional ultrasound, SWE, and their combination, the positive predictive value when using both (90.20%) was significantly greater than that when using conventional ultrasound (74.50%) or SWE alone (76.50%).Conclusion: The plantar fascia elastic parameter calculated with single-point ROIs set at the greatest thickness of the plantar fascia is positively correlated with fascia feel pain. Single-point analysis is sufficient for the screening of the early-stage plantar fasciopathy using SWE. SWEsingle-point may provide additional valuable information for assessing the severity of plantar fasciopathy

    Atherosclerosis and Helminths Infection

    Get PDF
    Atherosclerosis is a chronic disease that causes various cardiovascular complications. Plaque formation in atherosclerosis is considered similar to the pathogenesis of other autoimmune diseases; thus, immunomodulation and immunosuppression may present strategies for the treatment and prevention of these diseases. Interestingly helminth infection was found to inhibit T helper 1-mediated autoimmune diseases and T helper 2-mediated allergy and asthma, indicating significant potential for clinical application. Some study even found that therapeutic efficacy of the viable tapeworm was superior to dexamethasone treatment. Recently, some studies have shown an inverse association between helminth infections and inflammatory diseases, including diabetes mellitus, lipid abnormality, and atherosclerosis. Will the underlying mechanism bring us a new idea on the treatment for these diseases? We tried to find an answer by reviewing recent articles

    Research on Corn Ears’ Storage by Rectangle Small-scale Farm Bin with Steel Framework in Jizhou

    Get PDF
    The moisture of most newly harvested corn ears could be as high as 30% in Jizhou, and the method of air-drying on sides of roads, which is weather-sensitive, is mostly adopted in rural areas.Considering the small-scale farm bin has been used widely in the northeast of China, it is meaningful to explore its applicability and optimal thickness in Jizhou. In this study, JSWD-120 (4×1.5×2 m) is chosen and modified into tree small-scale bins with the thickness of 0.8 m, 1.0 m and 1.2 m. The newly harvest corn ears are stored from the middle October to early April and different quality index are analyzed timely. Results show that corn ears stored in the bin with the thickness of 1.2 m show good quality in terms of moisture of 14.05%±0.001%, lower fatty acid values of (51.59±0.007) mgKOH/100g, crude starch content of (68.66±0.171) g/100g and amylose content of 20.65%. Moreover, mycotoxins, such as deoxynivalenol and ochratoxin A, are not detected. Based on the experiment results, it is reasonable to consider wider utilization of JSWD farm bins to the south of Chin

    TMRT observations of 26 pulsars at 8.6 GHz

    Full text link
    Integrated pulse profiles at 8.6~GHz obtained with the Shanghai Tian Ma Radio Telescope (TMRT) are presented for a sample of 26 pulsars. Mean flux densities and pulse width parameters of these pulsars are estimated. For eleven pulsars these are the first high-frequency observations and for a further four, our observations have a better signal-to-noise ratio than previous observations. For one (PSR J0742-2822) the 8.6~GHz profiles differs from previously observed profiles. A comparison of 19 profiles with those at other frequencies shows that in nine cases the separation between the outmost leading and trailing components decreases with frequency, roughly in agreement with radius-to-frequency mapping, whereas in the other ten the separation is nearly constant. Different spectral indices of profile components lead to the variation of integrated pulse profile shapes with frequency. In seven pulsars with multi-component profiles, the spectral indices of the central components are steeper than those of the outer components. For the 12 pulsars with multi-component profiles in the high-frequency sample, we estimate the core width using gaussian fitting and discuss the width-period relationship.Comment: 33 pages, 49 figures, 5 Tables; accepted by Ap
    corecore