174 research outputs found

    Empirical Study of Travel Time Estimation and Reliability

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    This paper explores the travel time distribution of different types of urban roads, the link and path average travel time, and variance estimation methods by analyzing the large-scale travel time dataset detected from automatic number plate readers installed throughout Beijing. The results show that the best-fitting travel time distribution for different road links in 15 min time intervals differs for different traffic congestion levels. The average travel time for all links on all days can be estimated with acceptable precision by using normal distribution. However, this distribution is not suitable to estimate travel time variance under some types of traffic conditions. Path travel time can be estimated with high precision by summing the travel time of the links that constitute the path. In addition, the path travel time variance can be estimated by the travel time variance of the links, provided that the travel times on all the links along a given path are generated by statistically independent distributions. These findings can be used to develop and validate microscopic simulations or online travel time estimation and prediction systems

    Let Segment Anything Help Image Dehaze

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    The large language model and high-level vision model have achieved impressive performance improvements with large datasets and model sizes. However, low-level computer vision tasks, such as image dehaze and blur removal, still rely on a small number of datasets and small-sized models, which generally leads to overfitting and local optima. Therefore, we propose a framework to integrate large-model prior into low-level computer vision tasks. Just as with the task of image segmentation, the degradation of haze is also texture-related. So we propose to detect gray-scale coding, network channel expansion, and pre-dehaze structures to integrate large-model prior knowledge into any low-level dehazing network. We demonstrate the effectiveness and applicability of large models in guiding low-level visual tasks through different datasets and algorithms comparison experiments. Finally, we demonstrate the effect of grayscale coding, network channel expansion, and recurrent network structures through ablation experiments. Under the conditions where additional data and training resources are not required, we successfully prove that the integration of large-model prior knowledge will improve the dehaze performance and save training time for low-level visual tasks

    A Comprehensive Study on Knowledge Graph Embedding over Relational Patterns Based on Rule Learning

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    Knowledge Graph Embedding (KGE) has proven to be an effective approach to solving the Knowledge Graph Completion (KGC) task. Relational patterns which refer to relations with specific semantics exhibiting graph patterns are an important factor in the performance of KGE models. Though KGE models' capabilities are analyzed over different relational patterns in theory and a rough connection between better relational patterns modeling and better performance of KGC has been built, a comprehensive quantitative analysis on KGE models over relational patterns remains absent so it is uncertain how the theoretical support of KGE to a relational pattern contributes to the performance of triples associated to such a relational pattern. To address this challenge, we evaluate the performance of 7 KGE models over 4 common relational patterns on 2 benchmarks, then conduct an analysis in theory, entity frequency, and part-to-whole three aspects and get some counterintuitive conclusions. Finally, we introduce a training-free method Score-based Patterns Adaptation (SPA) to enhance KGE models' performance over various relational patterns. This approach is simple yet effective and can be applied to KGE models without additional training. Our experimental results demonstrate that our method generally enhances performance over specific relational patterns. Our source code is available from GitHub at https://github.com/zjukg/Comprehensive-Study-over-Relational-Patterns.Comment: This paper is accepted by ISWC 202

    Hepcidin Plays a Key Role in 6-OHDA Induced Iron Overload and Apoptotic Cell Death in a Cell Culture Model of Parkinson’s Disease

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    Background. Elevated brain iron levels have been implicated in the pathogenesis of Parkinson’s disease (PD). However, the precise mechanism underlying abnormal iron accumulation in PD is not clear. Hepcidin, a hormone primarily produced by hepatocytes, acts as a key regulator in both systemic and cellular iron homeostasis. Objective. We investigated the role of hepcidin in 6-hydroxydopamine (6-OHDA) induced apoptosis in a cell culture model of PD. Methods. We downregulated hepcidin using siRNA interference in N27 dopaminergic neuronal cells and made a comparison with control siRNA transfected cells to investigate the role of hepcidin in 6-OHDA induced neurodegeneration. Results. Hepcidin knockdown (32.3%, P\u3c0.0001) upregulated ferroportin 1 expression and significantly (P\u3c0.05) decreased intracellular iron by 25%. Hepcidin knockdown also reduced 6-OHDA induced caspase-3 activity by 42% (P\u3c0.05) and DNA fragmentation by 29% (P=0.086) and increased cell viability by 22% (P\u3c0.05). In addition, hepcidin knockdown significantly attenuated 6-OHDA induced protein carbonyls by 52% (P\u3c0.05) and intracellular iron by 28% (P\u3c0.01), indicating the role of hepcidin in oxidative stress. Conclusions. Our results demonstrate that hepcidin knockdown protected N27 cells from 6-OHDA induced apoptosis and that hepcidin plays a major role in reducing cellular iron burden and oxidative damage by possibly regulating cellular iron export mediated by ferroportin 1

    Toward Real Flare Removal: A Comprehensive Pipeline and A New Benchmark

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    Photographing in the under-illuminated scenes, the presence of complex light sources often leave strong flare artifacts in images, where the intensity, the spectrum, the reflection, and the aberration altogether contribute the deterioration. Besides the image quality, it also influence the performance of down-stream visual applications. Thus, removing the lens flare and ghosts is a challenge issue especially in low-light environment. However, existing methods for flare removal mainly restricted to the problems of inadequate simulation and real-world capture, where the categories of scattered flares are singular and the reflected ghosts are unavailable. Therefore, a comprehensive deterioration procedure is crucial for constructing the dataset of flare removal. Based on the theoretical analysis and real-world evaluation, we propose a well-developed methodology for generating the data-pairs with flare deterioration. The procedure is comprehensive, where the similarity of scattered flares and the symmetric effect of reflected ghosts are realized. Moreover, we also construct a real-shot pipeline that respectively processes the effects of scattering and reflective flares, aiming to directly generate the data for end-to-end methods. Experimental results show that the proposed methodology add diversity to the existing flare datasets and construct a comprehensive mapping procedure for flare data pairs. And our method facilities the data-driven model to realize better restoration in flare images and proposes a better evaluation system based on real shots, resulting promote progress in the area of real flare removal

    Fermentation Products of Paenibacillus bovis sp. nov. BD3526 Alleviates the Symptoms of Type 2 Diabetes Mellitus in GK Rats

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    Gut microbiota is closely related to type 2 diabetes mellitus (T2DM). The gut microbiota of patients with T2DM is significantly different from that of healthy subjects in terms of bacterial composition and diversity. Here, we used the fermentation products of Paenibacillus bovis sp. nov. BD3526 to study the disease progression of T2DM in Goto-kakisaki (GK) rats. We found that the symptoms in GK rats fed the fermentation products of BD3526 were significantly improved. The 16S rRNA sequencing showed that the fermentation products of BD3526 had strong effects on the gut microbiota by increasing the content of Akkermansia. In addition, the interaction of the genus in the gut of the BD3526 group also significantly changed. Additional cytokine detection revealed that the fermentation products of BD3526 can reduce the inflammatory factors in the intestinal mucus of GK rats and thereby inhibit the inflammatory response and ameliorate the symptoms of T2DM

    Mechanical and Electrical Properties of a CFETR CSMC Conductor under Transverse Mechanical Loadings

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    The central solenoid model coil (CSMC) project of the China Fusion Engineering Test Reactor was launched in 2014 to verify the technological feasibility of a large-scale superconducting magnet at the Institute of Plasma and Physics Chinese Academy of Sciences. The short twist pitch design recommended by CEA is chosen for the CSMC Nb3Sn cable-in-conduit conductors. In order to better understand the evolution of transport properties and coupling losses related to the effect of electromagnetic load cycles, the mechanical and electrical properties were measured and investigated employing a special cryogenic press facility for the transverse mechanical loadings. The results show that the transverse compression (dy) versus applied load force (Fy ) is different from first to subsequent loading cycles. This mechanical behavior can be interpreted by the combination of strands bending between the crossovers and strands deformation at the crossovers. The fitting relations of dy versus Fy are also presented. The evolution of interstrand contact resistance (Rc) in the cabling stages with cyclic history and pressure effects are discussed. In addition, a fitting relation of Rc versus Fy is presented based on a combination of strand's microsliding and copper matrix resistivity. A clear correlation between intrapetal resistance Rc and coupling loss is also found

    The Sphingosine-1-Phosphate/Sphingosine-1-Phosphate Receptor 2 Axis in Intestinal Epithelial Cells Regulates Intestinal Barrier Function During Intestinal Epithelial Cells–CD4+T-Cell Interactions

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    Background/Aims: Epithelial cells line the intestinal mucosa and form an important barrier for maintaining host health. This study aimed to explore the mechanism of the Sphingosine-1-phosphate (S1P)/Sphingosine-1-phosphate receptor 2 (S1PR2) pathway in intestinal epithelial cells (IECs) that participate in the intestinal barrier function. Methods: In this study, we constructed a knockout of the S1PR2 gene in mice, and Dextra sulfate sodium (DSS) was used to induce colitis. We isolated IECs from wild type (WT) and S1PR2–/– mice, and the endogenous expression of S1PR2 and Zonula occludens 1 (ZO-1) in IEC were detected by Western blot. Next, the major histocompatibility complex II (MHC-II) expression was analyzed by reverse transcription quantitative real-time (RT-qPCR) and flow cytometry. The in vivo and in vitro intestinal permeability were evaluated by serum fluorescein isothiocyanate (FITC) concentration. The tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interferon-γ (IFN-γ) levels in cell suspension were analyzed by enzyme-linked immuno sorbent assay (ELISA). A carboxyfluorescein diacetate succinimidyl ester (CFSE) assay was used to detect the T-cell proliferation in a co-culture system. Results: The intestinal mucosal barrier damage in S1PR2–/– mice was more severe than in the WT mice, and there were more CD4+T-cells in the colon tissue of DSS-treated S1PR2–/– mice. Either the mouse colon carcinoma cell line (CT26. WT) or the IECs upregulated MHC-II expression, which then promoted CD4+T-cell proliferation. The S1P/S1PR2 pathway controlled MHC-II expression to regulate CD4+T-cell proliferation via the extracellular signal-regulated kinase (ERK) pathway. In addition, the IFN-γ that was secreted by CD4+T-cells increased DSS-induced damage of intestinal epithelial cell barrier function. ZO-1 expression was increased by S1P in CT26.WT cells, while S1PR2 antagonist JTE-013 expression was downregulated. However, in CT26.WTsi-S1PR2 cells, S1P had no effect on ZO-1 expression. Conclusions: The S1P/S1PR2 axis in IECs mediated CD4+T-cell activation via the ERK pathway and MHC-II expression to regulate intestinal barrier function

    Nanoneuromedicines for degenerative, inflammatory, and infectious nervous system diseases

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    Interest in nanoneuromedicine has grown rapidly due to the immediate need for improved biomarkers and therapies for psychiatric, developmental, traumatic, inflammatory, infectious and degenerative nervous system disorders. These, in whole or in part, are a significant societal burden due to growth in numbers of affected people and in disease severity. Lost productivity of the patient and his or her caregiver, and the emotional and financial burden cannot be overstated. The need for improved health care, treatment and diagnostics is immediate. A means to such an end is nanotechnology. Indeed, recent developments of health-care enabling nanotechnologies and nanomedicines range from biomarker discovery including neuroimaging to therapeutic applications for degenerative, inflammatory and infectious disorders of the nervous system. This review focuses on the current and future potential of the field to positively affect clinical outcomes. From the Clinical Editor Many nervous system disorders remain unresolved clinical problems. In many cases, drug agents simply cannot cross the blood-brain barrier (BBB) into the nervous system. The advent of nanomedicines can enhance the delivery of biologically active molecules for targeted therapy and imaging. This review focused on the use of nanotechnology for degenerative, inflammatory, and infectious diseases in the nervous system
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