349 research outputs found

    Understanding Impact of Angle in Urban Transportation

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    Traffic congestion at urban-scale levels occurs when road network supply is insufficient compared with demand. Therefore, the relationship between supply and demand has been extensively investigated in the literature. Especially the impact of a network's topology (i.e., connectivity) on traffic congestion has been widely studied. On the other hand, only a few studies analyze the relationship between the physical shape of the road network (i.e., morphology), demand, and congestion. For example, angular indicators associated with links and trips can be utilized to characterize such morphology. However, statistical analysis of angular indicators requires a specialized methodology called Directional Statistics, and how to apply Directional Statistics to traffic data is not obvious. Here, this study develops a descriptive model of traffic congestion based on Directional Statistics. It describes direction-dependent congestion levels using angular distributions that characterize the shape of road network and travel demand. Specifically, the shape of road network is characterized by the distribution of angles of each road link in a specific region. Likewise, the travel demand is characterized by the distribution of angles of each trip in the region. Then, a statistical model that describes travel time for a trip with arbitrary direction by these two angular distribution is constructed by paying special attention to the fact that roads and demands from all angles would affect congestion. A simple estimation method for the proposed model is also presented. Finally, the model was estimated using actual data in Tokyo, and the relationship between the characteristics of the shape of the road network, the direction of demand, and congestion is analyzed from the new perspective of angles

    A Macro-Micro Approach to Reconstructing Vehicle Trajectories on Multi-Lane Freeways with Lane Changing

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    Vehicle trajectories can offer the most precise and detailed depiction of traffic flow and serve as a critical component in traffic management and control applications. Various technologies have been applied to reconstruct vehicle trajectories from sparse fixed and mobile detection data. However, existing methods predominantly concentrate on single-lane scenarios and neglect lane-changing (LC) behaviors that occur across multiple lanes, which limit their applicability in practical traffic systems. To address this research gap, we propose a macro-micro approach for reconstructing complete vehicle trajectories on multi-lane freeways, wherein the macro traffic state information and micro driving models are integrated to overcome the restrictions imposed by lane boundary. Particularly, the macroscopic velocity contour maps are established for each lane to regulate the movement of vehicle platoons, meanwhile the velocity difference between adjacent lanes provide valuable criteria for guiding LC behaviors. Simultaneously, the car-following models are extended from micro perspective to supply lane-based candidate trajectories and define the plausible range for LC positions. Later, a two-stage trajectory fusion algorithm is proposed to jointly infer both the car-following and LC behaviors, in which the optimal LC positions is identified and candidate trajectories are adjusted according to their weights. The proposed framework was evaluated using NGSIM dataset, and the results indicated a remarkable enhancement in both the accuracy and smoothness of reconstructed trajectories, with performance indicators reduced by over 30% compared to two representative reconstruction methods. Furthermore, the reconstruction process effectively reproduced LC behaviors across contiguous lanes, adding to the framework's comprehensiveness and realism

    Monocyte/macrophage response to β2-microglobulin modified with advanced glycation end products

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    Monocyte/macrophage response to β2-microglobulin modified with advanced glycation end products. We recently found that acidic β2-microglobulin (β2m), a major isoform of β2m in amyloid fibrils of patients with dialysis-related amyloidosis (DRA), contained early Amadori products and advanced glycation end products (AGEs) formed nonenzymatically between sugar and protein. Further analysis revealed that acidic β2m induces monocyte chemotaxis and macrophage secretion of bone-resorbing cytokines, suggesting the involvement of acidic β2m in the pathogenesis of DRA. Acidic β2m, however, is a mixture of heterogeneous molecular adducts due to various types of modification. In the present study, we investigated the modification responsible for the biological activity of acidic β2m toward monocytes/macrophages. The presence of a fair amount of β2m species with deamidation was detected in acidic β2m isolated from urine of non-diabetic long-term hemodialysis patients, but deamidated β2m had no biological activity. In contrast, normal β2m acquired the activity upon incubation with glucose in vitro. Among the glycated β2m, the pigmented and fluorescent β2m that formed after a long incubation period, that is, AGE-modified β2m, exhibited biological activity, whereas β2m modified with Amadori products, major Maillard products in acidic β2m, had no such activity. These findings suggest that AGEs, although only a minor constituent of acidic β2m, are responsible for monocyte chemotaxis and macrophage secretion of cytokines, implicating the contribution of AGEs to bone and joint destruction in DRA

    Vestibule-Middle Ear Dehiscence Tested With Perilymph-Specific Protein Cochlin-Tomoprotein (CTP) Detection Test

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    An 8-year-old boy was referred to the ENT department for further evaluation of right-sided conductive hearing loss. A small cyst anterior to the oval window and fixation of the stapes footplate were observed during an exploratory tympanotomy. The concentration of a perilymph-specific protein, cochlin-tomoprotein (CTP), in the middle ear lavage fluid was measured with an ELISA-based CTP detection kit. The level of CTP in the middle ear lavage fluid before fenestration of the cyst was 0.26 ng/ml (negative), and its level after fenestration was 2.98 ng/ml (positive), confirming the presence of perilymph in the cyst. A small bone dehiscence, considered to be the fissula ante fenestram, was observed anterior to the stapes footplate after removal of the cyst. The CTP detection test results allowed us to confirm that the small bone dehiscence was connected to the inner ear

    CORRELATION BETWEEN THROWING MOTION AND MAXIMUM ELBOW VARUS TORQUE IN FEMALE PROFESSIONAL BASEBALL PITCHERS

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    The purpose of this study was to identify the correlation between throwing motion and maximum elbow varus torque (MEV) in female professional baseball pitchers. Twelve pitchers without pre-existing pain were recruited. Ball velocity and pitching motion were measured. Ball velocity and, kinematic and kinetic data from each joint during the pitch were extracted to evaluate the correlation with MEV. There was no correlation between the fastest ball velocity and MEV. Sixteen kinematic and kinetic parameters were found to have significant correlations with MEV. Particularly, as trunk rotation angle to the non-throwing direction before lead foot contact (FC) increased, the MEV decreased. Rotating the trunk in the non-throwing direction before FC and immediately in the throwing direction after FC could be a key component of the throwing motion

    Pain following COVID-19 vaccination

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    Pain at the injection site is the most frequent reaction among COVID-19 vaccine recipients, but its characteristics were not fully described yet. The purpose of this study was to investigate multiple domains of pain following BNT162b2 mRNA vaccination. We included 107 subjects undergoing primary shot of the vaccination twice into deltoid muscle with a 3-week interval. They completed 6 sessions of pain assessments, one before the first and second dose (1-0, 2-0), and 1st / 7th day after the first and second dose (1-1 / 1-7, 2-1 / 2-7). Pain visual analog scale (VAS), pain distribution, and pressure pain threshold (PPT) on deltoid muscle were evaluated in each session. The mean VAS (at rest / shoulder motion) was 6.0 / 27.6 mm at 1-1, and 12.8 / 34.0 mm at 2-1. Approximately, 90% of recipients showed localized pain within the upper arm. Percentage change of PPTs at 1-1 and 2-1 was bilaterally (ipsilateral / contralateral) decreased to 87.4 / 89.4% and 80.6 / 91.0%, which was recovered to the baseline level at 1-7 and 2-7. Temporary, mild-to-moderate intensity, localized distribution, concomitant with bilateral mechanical hyperalgesia on the deltoid muscle, were typical pain characteristics following this vaccination. These findings provide a rationale that will be informative for future recipients

    Impact of Coronary Plaque Composition on Cardiac Troponin Elevation After Percutaneous Coronary Intervention in Stable Angina Pectoris : A Computed Tomography Analysis

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    ObjectivesThe authors used multidetector computed tomography (MDCT) to study the relation between culprit plaque characteristics and cardiac troponin T (cTnT) elevation after percutaneous coronary intervention (PCI).BackgroundPercutaneous coronary intervention is often complicated by post-procedural myocardial necrosis manifested by elevated cardiac biomarkers.MethodsStable angina patients (n = 107) with normal pre-PCI cTnT levels underwent 64-slice MDCT before PCI to evaluate plaque characteristics of culprit lesions. Patients were divided into 2 groups according to presence (group I, n = 36) or absence (group II, n = 71) of post-PCI cTnT elevation ≥3 times the upper limit of normal (0.010 ng/ml) at 24 h after PCI.ResultsComputed tomography attenuation values were significantly lower in group I than in group II (43.0 [26.5 to 75.7] HU vs. 94.0 [65.0 to 109.0] HU, p 1.05; odds ratio: 4.54; 95% confidence interval: 1.36 to 15.9; p = 0.014) and spotty calcification (odds ratio: 4.27; 95% confidence interval: 1.30 to 14.8; p = 0.016) were statistically significant independent predictors for cTnT elevation. For prediction of cTnT elevation, the presence of all 3 variables (CT attenuation value 1.05, and spotty calcification) showed a high positive predictive value of 94%, and their absence showed a high negative predictive value of 90%.ConclusionsMDCT may be useful in detecting which lesions are at high risk for myocardial necrosis after PCI
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