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This study investigated the regulation effect of magnetic field combined with low temperature storage on postharvest quality and cell wall pectic-polysaccharide degradation of wampee stored for 15 d at 4 °C and 15 °C. Results showed that magnetic field combined with low temperature storage reduced browning rate of fruit after 15 d storage, but its effect on weight loss rate and total soluble solids (TSS) did not surpass that of storage temperature. Interestingly, contents of flavonoid, total phenols and malondialdehyde (MDA) were also lowered at varying degrees by combined treatment. Furthermore, molecular weight distribution and monosaccharide compositions of cell wall pectic-polysaccharides were also affected, which resulted from the coordinated action of cell wall pectin-degrading enzymes. The activities of these enzymes during storage, including polygalacturonase (PG), pectin methylesterase (PME) and β-galactosidase (β-Gal) in treated wampee decreased. These findings suggested that magnetic field combined with low temperature storage was an effective technology and had great potential in preservation of postharvest wampee in future.

Micro-milling, widely employed across various fields, faces significant challenges due to the small diameter and limited stiffness of its tools, making the process highly susceptible to cutting chatter and premature tool breakage. Ensuring stable and safe cutting processes necessitates the prediction of chatter by considering the tool breakage. Crucially, the modal parameters of the spindle–holder–tool system are important prerequisites for such stability prediction. In this paper, the frequency response functions (FRFs) of the micro-milling tool are calculated by direct FRFs of the micro-milling cutter and cross FRFs between a point on the shank and one on the tool tip. Additionally, by utilizing a cutting force model specific to micro-milling, the bending stress experienced by the tool is computed, and the tool breakage curve is subsequently determined based on the material’s permissible maximum allowable stress. The FRFs of the micro-milling tool, alongside the tool breakage curve, are then integrated to generate the final stability lobe diagrams (SLDs). The effectiveness and reliability of the proposed methodology are confirmed through a comprehensive series of numerical and experimental validations.

Abstract Background Neutropenic children with hematological diseases were associated with higher morbidity of carbapenem-resistant enterobacteriaceae (CRE) blood-stream infection (BSI) or colonization. But it was still murky regarding clinical characteristics, antimicrobial susceptibility, and outcomes of CRE-BSI in these patients. We aimed to identify the potential risk factors for subsequent bacteremia and clinical outcome caused by CRE-BSI. Methods Between 2008 and 2020, 2,465 consecutive neutropenic children were enrolled. The incidence and characteristics of CRE-BSI were explored in CRE-colonizers versus non-colonizers. Survival analysis was performed and risk factors for CRE-BSI and 30-day mortality were evaluated. Results CRE-carriers were identified in 59/2465 (2.39%) neutropenic children and19/59 (32.2%) developed CRE-BSI, while 12/2406 (0.5%) of non-carriers developed CRE-BSI (P

In this study, alkali-soluble polysaccharide from wampee (ASP-W) was prepared and its effect on chitosan-based composite film was investigated. Preliminary characterization of ASP-W showed it was a kind of typical homogeneous polysaccharide, with a molecular weight of 1.5 × 103 KDa. Infrared spectroscopy proved the successful combination of ASP-W with chitosan. Meanwhile, composite film exhibited increased thickness, water solubility percentage, and swelling ratio and decreased moisture content. In terms of optical transmittance, composite films showed excellent UV barrier capability below 400 nm. Mechanical tests demonstrated tensile strength up to 24.84 MPa at ASP-W 1.5% and elongation at break up to 27.93% at ASP-W 4.5%. Composite films also possessed better barrier properties. Differential scanning calorimeter (DSC) results also indicated better thermostability of composite films. DPPH radical scavenging reached 46.84% at ASP-W 1.5% and hydroxyl radical scavenging peaked at 97.16% at ASP-W 3%. In summary, ASP-W can improve optical, mechanical, barrier, and thermal stability and antioxidant properties of chitosan film, which provided a certain reference for the development and utilization of polysaccharide in edible packaging film.

This paper proposes a novel unsupervised clustering framework to identify driving style not in terms of the discrete features of driving behavior data, but rather the time-varying patterns of driving maneuver intensity. This framework can describe the dynamic decision-making process of driving behavior and the continuity of driving data, and driving maneuver intensity is the basic of this paper. Therefore, detection, feature analysis and clustered on intensity of driving maneuvers are carried out using a threshold-based approach, hierarchical feature extraction, and k-means clustering. Then, to analyze fine-grained driving style, dynamic time windows are determined according to road alignment. In dynamic time windows, this paper constructs time-varying patterns based on driving maneuver intensity, which consider the intensity and frequency of driving behavior and preserve the time-varying characteristics of time-series data. However, not all dynamic time windows are equal in maneuvers’ duration and number, which means the time-varying patterns of driving maneuver intensity are curves with various lengths. So that, for clustering time-varying patterns, this paper proposes a novel curve clustering algorithm named Similarity-Based Clustering with Dynamic Time Warping (SBC-DTW) that can cluster curves with various lengths. The empirical results based on real driving data demonstrate that the proposed framework can classify driving style more accurately than the classical method. Moreover, according to this framework, we can have an in-depth understanding of dynamic driving behavior and the composition of drivers’ long-term driving styles.

The trajectory prediction of surrounding vehicles is the basis for reasonable decision-making of autonomous vehicles (AV), which is helpful for improving their safety and comfort. Aiming to predict lane-changing trajectories, we propose a behavior-based method of predicting diverse lane-changing trajectories of surrounding vehicles, which includes two parts: lane-changing behavior recognition and diverse lane-changing trajectory prediction. Firstly, a lane-changing behavior recognition model based on the Continuous Hidden Markov Model (CHMM) is established to identify the lane-changing behavior of surrounding vehicles. Secondly, considering the driving styles will lead to diverse lane-changing patterns, a diverse lane-changing trajectory prediction method based on LSTM is proposed to predict three lane-changing trajectories when the driving style is unknown, which is composed of three LSTM trajectory generators representing three lane-changing patterns. Finally, the Next Generation Simulation (NGSIM) dataset is used to train, validate and test the behavior recognition model and the trajectory prediction model. The results show good accuracy and anticipative ability of the behavior recognition model. The average accuracy of surrounding vehicle behavior detection is 98.98%, the accuracy of surrounding vehicle behavior detection in 2s before lane change point is above 95%, the average anticipation time of left and right lane-changing behavior recognition is 3.24s and 3.71s, the average proportion of anticipation time in the lane-changing duration time is 46.78% and 55.54%. In the trajectory prediction section, with considering the diversity of lane changing trajectory caused by driving style, the proposed method for predicting diverse lane-changing trajectories reduces the error between the predicted and actual trajectories. The Root Mean Square Error (RMSE) and the Final Displacement Error (FDE) of the longitudinal and lateral positions are reduced by more than 21% over a 5s time horizon. In conclusion, the diverse trajectory prediction method based on the early detection of lane-changing behavior can provide AV with future trajectory of other vehicle under different driving styles, which is conducive to a more comprehensive and accurate driving risk assessment.

The eyes are the first channel used by humans to obtain various types of visual information from the outside world and, especially when driving, 80-90% of information is received through the eyes. Eye movement behaviors are generally divided into six types, but attention is often paid to fixation, saccade, and smooth pursuit. Due to their importance, it is essential to classify eye movement behaviors accurately. The classification of eye movements should be a complete process, including the three steps of pre-processing, classification, and post-processing. However, it is very uncommon for all of these steps to be included in the eye-tracking literature when eye movement classification is discussed. Therefore, first, this paper proposes a refined eye movement data pre-processing framework and an improved method consisting of three steps is introduced. Second, an eye movement classification algorithm based on an improved decision tree that is independent of the threshold setting and application environment is proposed, and a post-processing consisting of merging adjacent fixations and discarding short fixations is described. Finally, the application of the classified eye movement behavior in the driving field is described, including the estimation of preview time using fixation and the estimation of time-to-collision using smooth pursuit. Two important results are obtained in this paper. One concerns the classification accuracy of eye movement behavior, the F1-scores of fixation, saccade, and smooth pursuit being respectively 92.63%, 93.46%, and 65.29%, which are higher than the scores of other algorithms. The other relates to the application to driving. On the one hand, the preview time calculated by fixation is mostly distributed around 1-6s, which is closer to reality than the traditional setting of 1s. At the same time, the regression relationship between the preview time and the road turning radius is also quantitatively analyzed and their regression function is obtained. On the other hand, the average estimated error of time-to-collision used by smooth pursuit is 7.37%. These results can play an important role in the development of ADAS and the improvement of traffic safety.

BackgroundApproximately 10–40% of people with human immunodeficiency virus (HIV) infection are unable to obtain successful improvements in immune function after antiretroviral therapy (ART). These patients are at greater risk of developing non-acquired immunodeficiency syndrome (AIDS)-related conditions, with the accompanying increased morbidity and mortality. Discovering predictive biomarkers can help to identify patients with a poor immune response earlier and provide new insights into the mechanisms of this condition.MethodsA total of 307 people with HIV were enrolled, including 110 immune non-responders (INRs) and 197 immune responders (IRs). Plasma samples were taken before ART, and quantities of plasma microRNAs (miRNAs) were determined using reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). Candidate biomarkers were established through four phases: discovery, training, validation, and blinded test. Binary logistic regression was used to analyze the combined predictive capacity of the identified miRNAs. The effect of one miRNA, miR-16-5p, on T cell function was assessed in vitro.ResultsExpression of five miRNAs (miR-580, miR-627, miR-138-5p, miR-16-5p, and miR-323-3p) was upregulated in the plasma of INRs compared with that in IRs. Expression of these miRNAs was negatively correlated with both CD4+ T cell counts and the increase in the proportion of CD4+ T cells after one year of ART. These five miRNAs were combined in a predictive model, which could effectively identify INRs or IRs. Furthermore, we found that miR-16-5p inhibits CD4+ T cell proliferation by regulating calcium flux.ConclusionWe established a five-miRNA panel in plasma that accurately predicts poor immune response after ART, which could inform strategies to reduce the incidence of this phenomenon and improve the clinical management of these patients.

Fluorescent supramolecular coordination complexes are of interest for chemical sensing and optical devices. Here the authors synthesize nine organoplatinum metallacycles with high quantum yields, whose fluorescence wavelengths are tuned through manipulation of their photoinduced electron transfer and intramolecular charge transfer properties.

The design of heat exchanger structure relies more on experience and lacks a guiding method. In view of this, this paper takes existing heat exchanger design structure as the research object minimizing mean square error of velocity at the outlet of coal pyrolysis heat exchanger. Optimization parameters are selected according to characteristics of model structure, and a three-dimensional model is established for each parameter value. The CFD numerical simulation method is used for trial calculation, and simulation results were numerically analyzed. The optimization parameters are taken as independent variables, numerical analysis results of mean square error are used as dependent variables to fit function curve and obtain function equation. Taguchi method is used to design an orthogonal experiment to obtain the weights of optimization parameters on objective function. Then the function equation is weighted to obtain a weighting function. Finally, genetic algorithm program is developed to find the optimal solution. Qualitative and quantitative analysis show that optimal solution results in a 36% reduction in the mean squared velocity at outlet of heat exchanger. The research results have a great significance to the design of heat exchangers.

Aromatic Chinese herbs have been used to prevent plagues since ancient times. Traditional Chinese medicine has unique advantages in the prevention and treatment of epidemic diseases. According to the traditional Chinese medicine treatment plan in the National COVID-19 Diagnosis and Treatment Plan (Trial Seventh Edition) of the National Health Commission, Chinese patent medicines or prescriptions rich in aromatic Chinese herbs are selected for prevention and treatment during the period of medical observation, clinical treatment, and recovery of confirmed COVID-19 patients. Some local health committees or traditional Chinese medicine administrations recommend a variety of other ways of using traditional aromatic Chinese herbs to prevent and cure COVID-19. These involve external fumigation, use of moxibustion, and wearing of sachet. The efficacy of aromatic Chinese herbs plays a decisive role in the prevention and treatment of COVID-19. The unique properties, chemical composition, and mechanism of action of aromatic Chinese herbs are worthy of extensive and in-depth experimental and clinical research. The findings are expected to provide a reference for follow-up treatment of novel coronavirus and the development of corresponding drugs. In 2003, Dayuan-Yin produced excellent results in the treatment of the SARS virus. Individually, 112 confirmed cases were administered this drug between January and April 2003, and more than 93.7% of the patients showed noticeable mitigation of the symptoms, as well as recovery. Dayuan-Yin also was selected as one of the nationally recommended prescriptions for the COVID-19. Based on the national recommendation of Dayuan-Yin prescription, this review discusses the role of volatile components in the prevention and treatment of COVID-19, and speculates the possible mechanism of action, so as to provide a basis for the prevention and treatment of COVID-19.

Performance evaluation is a necessary stage in development of tracking control strategy of autonomous vehicle system, which determines the scope of application and promotes further improvement. At present, most of the tracking control strategies include performance evaluation. However, performance evaluation criteria differ from work to work, lacking comprehensive evaluation system. This article proposes a multidimensional integrated tracking control evaluation system based on subjective and objective weighting, taking into account the tracking accuracy, driving stability, and ride comfort. Through the co-simulation of CarSim and Simulink, qualitative analysis and quantitative analysis based on multidimensional evaluation system of five coupled longitudinal and lateral control strategies (lateral: pure pursuit feedforward control, dynamic-model-based optimal curvature control (dynamic feedforward control), Stanley feedback control, kinematics feedback control, and dynamic feedback control; longitudinal: the incremental proportion–integration–differentiation control) under typical operating conditions are carried out to analyze the operating range and robustness of each tracking control strategy. The results show that the Stanley tracking control strategy and the dynamic feedback tracking control strategy have a wide range of applications and robustness. The consistency of qualitative analysis results and the quantitative analysis results verify the validity and feasibility of the evaluation system.

Lectin from loach skin mucus plays an important role in pathogen defense. However, hardly can any paper relevant to the character of lectin from loach skin mucus be found in recent years. In this study, a kind of new lectin (LML), with a high hemagglutination activity of 166.23 × 103 HU/mg, was successfully isolated and purified from loach skin mucus. LML was a kind of glycoprotein with a molecular weight of 245 kDa. Also, the monosaccharide composition suggested that its carbohydrate chain was composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose with a molar ratio of 2.02 : 11.66 : 2.06 : 1.00 : 14.09 : 6.00. Besides, LML depended on Ca2+ to induce hemagglutination and was strongly inhibited by D-lactose. The lectin exhibited powerful resistance to alkali and kept about 30% hemagglutination activity at pH 14.0, whereas its capacity of acid resistance was weak. The maximum hemagglutination activity of LML maintained at a temperature range from 20°C to 50°C. Moreover, the structure of LML was preliminarily studied, indicating it contained abundant glutamic acid, histidine, and serine, and its secondary structure contained α-helix (4.97%), β-sheet (27.55%), turns structure (49.78%), and unordered structure (17.70%).

High sampling frequency of eye-trackers introduces noise in raw eye movement data. Furthermore, the unstable sampling frequency of devices generates fluctuating time interval between samples, which has negative influence on the quality of raw eye movement data. Therefore, the article aims to propose a valid and universal procedure on raw eye movement data processing. The procedure will be suitable for eye movement data collected by most types of eye-trackers. Characteristics of raw eye movement data were analyzed, and a comprehensive data processing procedure was proposed. Steps in this procedure include preliminary inspection of raw data, the checking and correction of actual sampling frequency, the selection of eye movement data, small gaps filled-in, data filtering, and fixation identification. By this procedure, raw eye movement data collected by eye-trackers can be used to identify types of eye movements and obtain fixation points in eye-tracking experiment. In the end, a paradigm test was designed to examine the correctness of data processing flow, and the application of eye movement data was also discussed.

Tank vehicles have quite poor roll stability in driving. Therefore, the purpose of this article is to investigate tankers’ roll stability by vehicle dynamic modeling. As a fluid–solid coupling multi-body system, tank vehicle’s dynamic modeling must take liquid sloshing into account. The conventional solution on liquid sloshing by hydrodynamics is difficult and time-consuming, and the modeling of tankers obtained by this method was a distributed parameter system with infinite degree of freedoms. It was quite difficult and complicated to analyze tankers’ dynamic features and to design active control system by the distributed parameter system. Therefore, three different methods to describe liquid sloshing effects in partially filled tanks with elliptical cross sections were proposed in this article, which are the estimation of liquid sloshing, the improved estimation of liquid sloshing, and the modeling of equivalent mechanical model for liquid sloshing. Then, the dynamic modeling of tank vehicles was commenced based on that. It was found out that the roll stability performance of tank vehicles obtained by different models differs with each other. The quasi-static model obtained by the estimation of liquid sloshing could get an estimation on tanker’s rollover threshold quickly and easily, but it is with poor accuracy. The improved quasi-static model obtianed by the improved estimation of liquid sloshing could give a more accurate result on tanker’s rollover threshold, the solution is also easily and quickly. Rollover analysis based on equivalent mechanical model of liquid sloshing could reflect vehicle’s dynamics and is with high accuracy, but the process is of great complexity.

Background/AimsInfectious mononucleosis (IM) is the clinical presentation of primary infection with Epstein-Barr virus. Although the literature contains a massive amount of information on IM, most of this is related specifically to only children or adults separately. In order to distinguish any differences between preschool children and youth patients, we retrospectively analyzed their demographic and clinical features.MethodsRecords of patients hospitalized from December 2001 to September 2011 with a diagnosis of IM were retrieved from Peking University First Hospital, which is a tertiary teaching hospital in Beijing. The demographic data and clinical characteristics were collected.ResultsIM was diagnosed in 287 patients during this 10-year period, with incidence peaks among preschool children (≤7 years old, 130/287, 45.3%) and youth patients (>15 and

To investigate drivers’ visual strategies and the distribution of fixation points, much work had been done and salient conclusions had been drawn. However, there is still no consensus on what the gaze target is and what functional significance the point might have. To improve theories on this subject, research was done to investigate drivers’ visual characteristics. On-road experiment was carried out, and drivers’ eye-movement and vehicle driving parameters were registered when driving around left- and right-hand curves. The results showed that drivers’ gaze direction fluctuates around the reference axis, and the fixation points are distributed in the region centered on the horizontal gaze position rather than a particular point that has geographical meanings. With the consideration of the traffic rules in China, we suggest here that there is no particular point on which drivers concentrate. Any point or position that could indicate the bend’s curvature could be the so-called target point. Drivers just want to operate their vehicle so as to pass through bends safely in a comfortable and labor-saving way.

To explore the relation between drivers' eye movements and vehicle steering performance, 25 participants were employed to drive a test vehicle on appointed tortuous routes. The drivers' visual behavior was measured while they were driving, and experiment data collected on motorway on-ramps and interchanges were used to analyze the drivers' visual characteristics. The distribution density of the fixation points showed that the drivers paid attention to the inner road edge when turning left and the outer road edge when turning right. Meanwhile, the heights of the gaze targets hardly changed. Therefore, a further investigation discovered that the gaze trajectory was parallel to the vehicle's driving trajectory on one-way curves. Then, six types of gaze trajectories were derived, and models for each type were established. Combining these models with the fact that gaze points are always distributed along the nearby road edge, it was deduced that the starting point of the gaze trajectory when driving on curves has a salient influence on the driver's gaze trajectory.

With the rapid development of urban transport and the sharp increase in vehicle population, traffic accidents form one of the most important causes of urban traffic congestion other than the imbalance between traffic supply and demand. Traffic congestion causes severe problems, such as environment contamination and energy dissipation. Therefore, it would be useful to analyze the congestion propagation characteristics after traffic accidents. Numerical analysis and computer simulation were two of the typical methods used at present to study the traffic congestion propagation properties. The latter was more widespread as it is more consistent with the actual traffic flow and more visual than the former. In this paper, an improved cellular automata (CA) model was presented to analyze traffic congestion propagation properties and to evaluate control strategies. In order to apply them to urban traffic flow simulation, the CA models have been improved and expanded on. Computer simulations were built for congestion not only extending to the upstream intersection, but also the upstream intersection and the entire road network, respectively. Congestion propagation characteristics after road traffic accidents were obtained, and controls of different severities and durations were analyzed. The results provide the theoretical foundation and practical means for the control of congestion.

Plenty of experiments and data analysis of vehicle track type in road curved section show that the deviation and the crossing characteristics of vehicle track paths are directly related to the driving stability and security. In this paper, the concept of driving dangerous area in curved section was proposed based on the vehicle track characteristics according to driving behavior decision making and accident probability. Taking the observation data of passenger cars as the representative, the vehicle track paths deviation regularity per measurement direction were analyzed by SPSS under the condition of different radius and different road cross section. The distribution probability of different track type and the accident probability calculation methods and results between opposite direction vehicles were given based on the track characteristics. Keywords: Vehicle Track Type; Track Deviation; SPSS Analysis, Accident probability; Driving Decision Making, Driving Dangerous Area.