113 research outputs found

    Causes and classification of EMD mode mixing

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    At present, the lack of insight into the problem of mode mixing in Empirical Mode Decomposition (EMD) hinders the development of solutions to the problem. Starting with the phenomenon that the EMD decomposition cannot be accomplished when the number of signal extrema is abnormal, the causes of mode mixing were investigated and the conclusion was reached that there are only two basic types of mode mixing. In light of this finding, the mechanisms of the three typical mode mixing solutions and their limitations were analyzed. It was found from the analysis process and results that the findings of this study regarding the causes and types of mode mixing were correct

    Modeling Lane-Changing Behavior in Freeway Off-Ramp Areas from the Shanghai Naturalistic Driving Study

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    The objective of this study is to investigate lane-changing characteristics in freeway off-ramp areas using Shanghai Naturalistic Driving Study (SH-NDS) data, considering a four-lane freeway stretch in various traffic conditions. In SH-NDS, the behavior of drivers is observed unobtrusively in a natural setting for a long period of time. We identified 433 lane-changing events with valid time series data from the whole dataset. Based on the logit model developed to analyze the choice of target lanes, a likelihood analysis of lane-changing behavior was graphed with respect to three traffic conditions: free flow, medium flow, and heavy flow. The results suggested that lane-changing behavior of exiting vehicles is the consequence of the balance between route plan (mandatory incentive) and expectation to improve driving condition (discretionary incentive). In higher traffic density, the latter seems to play a significant role. Furthermore, we found that lane-change from the slow lane to the fast lane would lead to higher speed variance value, which indicates a higher crash risk. The findings contribute to a better understanding on drivers’ natural driving behavior in freeway off-ramp areas and can provide important insight into road network design and safety management strategies

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    *These authors contributed equally to this study

    Efficient Health Data Transmission Method in a Wireless Body Area Network for Rural Elderly

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    The wireless body area network (WBAN) can monitor human physiological information for a long time and alleviate problems such as the imbalance of medical resources distribution and population aging. The complex human media may make data transmission unstable in wireless body area networks. A delay-tolerant WBAN opportunity transmission method based on human data priority was studied. In this method, the historical states between links are recorded by a sliding window. Then, the link stability is measured by a prediction function. At the same time, considering the heterogeneity of the data in the body area network, transmission priority is assigned to different health data. Combined with residual energy, link stability, and distance, the transmission cost of the candidate set is calculated, and the node with the lowest expected transmission cost is selected as the next hop to improve the reliability of data transmission. The experimental results showed that this method includes the characteristics of opportunity routing and WBAN to transmit health data with lower delay and higher efficiency than previous methods

    What’s on a prophage: analysis of Salmonella spp. prophages identifies a diverse range of cargo with multiple virulence- and metabolism-associated functions

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    ABSTRACT The gain of mobile elements, such as prophages, can introduce cargo to the recipient bacterium that could facilitate its persistence in or expansion to a new environment, such as a host. While previous studies have focused on identifying and characterizing the genetic diversity of prophages, analyses characterizing the cargo that prophages carry have not been extensively explored. We characterized prophage regions from 303 Salmonella spp. genomes (representing 254 unique serovars) to assess the distribution of prophages in diverse Salmonella. On average, prophages accounted for 3.7% (0.1%–8.8%) of the total genomic content of each isolate. Prophage regions annotated as Gifsy 1 and Salmon Fels 1 were the most commonly identified intact prophages, suggesting that they are common throughout the Salmonella genus. Among 21,687 total coding sequences (CDSs) from intact prophage regions in subsp. enterica genomes, 7.5% (median; range: 1.1%–47.6%) were categorized as having a function not related to prophage integration or phage structure, some of which could potentially provide a functional attribute to the host Salmonella cell. These predicted functions could be broadly categorized into CDSs involved in: (i) modification of cell surface structures (i.e., glycosyltransferases); (ii) modulation of host responses (e.g., SodC/SodA, SopE, ArtAB, and typhoid toxin); (iii) conferring resistance to heavy metals and antimicrobials; (iv) metabolism of carbohydrates, amino acids, and nucleotides; and (v) DNA replication, repair, and regulation. Overall, our systematic analysis of prophage cargo highlights a broader role for prophage cargo in influencing the metabolic, virulence, and resistance characteristics of Salmonella.IMPORTANCELysogenic bacteriophages (phages) can integrate their genome into a bacterial host's genome, potentially introducing genetic elements that can affect the fitness of the host bacterium. The functions of prophage-encoded genes are important to understand as these genes could be mobilized and transferred to a new host. Using a large genomic dataset representing >300 isolates from all known subspecies and species of Salmonella, our study contributes important new findings on the distribution of prophages and the types of cargo that diverse Salmonella prophages carry. We identified a number of coding sequences (CDSs) annotated as having cell surface-modifying attributes, suggesting that prophages may have played an important role in shaping Salmonella's diverse surface antigen repertoire. Furthermore, our characterization of prophages suggests that they play a broader role in facilitating the acquisition and transfer of CDSs associated with metabolism, DNA replication and repair, virulence factors, and to a lesser extent, antimicrobial resistance

    Efficient Health Data Transmission Method in a Wireless Body Area Network for Rural Elderly

    No full text
    The wireless body area network (WBAN) can monitor human physiological information for a long time and alleviate problems such as the imbalance of medical resources distribution and population aging. The complex human media may make data transmission unstable in wireless body area networks. A delay-tolerant WBAN opportunity transmission method based on human data priority was studied. In this method, the historical states between links are recorded by a sliding window. Then, the link stability is measured by a prediction function. At the same time, considering the heterogeneity of the data in the body area network, transmission priority is assigned to different health data. Combined with residual energy, link stability, and distance, the transmission cost of the candidate set is calculated, and the node with the lowest expected transmission cost is selected as the next hop to improve the reliability of data transmission. The experimental results showed that this method includes the characteristics of opportunity routing and WBAN to transmit health data with lower delay and higher efficiency than previous methods

    Modeling Lane-Changing Behavior in Freeway Off-Ramp Areas from the Shanghai Naturalistic Driving Study

    No full text
    The objective of this study is to investigate lane-changing characteristics in freeway off-ramp areas using Shanghai Naturalistic Driving Study (SH-NDS) data, considering a four-lane freeway stretch in various traffic conditions. In SH-NDS, the behavior of drivers is observed unobtrusively in a natural setting for a long period of time. We identified 433 lane-changing events with valid time series data from the whole dataset. Based on the logit model developed to analyze the choice of target lanes, a likelihood analysis of lane-changing behavior was graphed with respect to three traffic conditions: free flow, medium flow, and heavy flow. The results suggested that lane-changing behavior of exiting vehicles is the consequence of the balance between route plan (mandatory incentive) and expectation to improve driving condition (discretionary incentive). In higher traffic density, the latter seems to play a significant role. Furthermore, we found that lane-change from the slow lane to the fast lane would lead to higher speed variance value, which indicates a higher crash risk. The findings contribute to a better understanding on drivers’ natural driving behavior in freeway off-ramp areas and can provide important insight into road network design and safety management strategies

    MitoEVs: A new player in multiple disease pathology and treatment

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    Abstract Mitochondrial damage plays vital roles in the pathology of many diseases, such as cancers, neurodegenerative diseases, aging, metabolic diseases and many types of organ injury. However, the regulatory mechanism of mitochondrial functions among different cells or organs in vivo is still unclear, and efficient therapies for attenuating mitochondrial damage are urgently needed. Extracellular vesicles (EVs) are cell‐derived nanovesicles that can deliver bioactive cargoes among cells or organs. Interestingly, recent evidence shows that diverse mitochondrial contents are enriched in certain EV subpopulations, and such mitoEVs can deliver mitochondrial components to affect the functions of recipient cells under different conditions, which has emerged as a hot topic in this field. However, the overview and many essential questions with respect to this event remain elusive. In this review, we provide a global view of mitoEVs biology and mainly focus on the detailed sorting mechanisms, functional mitochondrial contents, and diverse biological effects of mitoEVs. We also discuss the pathogenic or therapeutic roles of mitoEVs in different diseases and highlight their potential as disease biomarkers or therapies in clinical translation. This review will provide insights into the pathology and drug development for various mitochondrial injury‐related diseases
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