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A three-dimensional ground-penetrating radar (GPR) captures non-destructively internal pavement distress characteristics. However, interpreting radar images and data analysis pose challenges. To improve the accuracy of distress identification, a three-dimensional digital model of internal pavement distress was established. Firstly, initial electromagnetic signal data were pre-processed to effectively eliminate spurious signals and enhance distress characteristic signals. The distress was located, and GPR images of typical distress were extracted and summarised. Next, the 3D dataset was constructed based on the pre-processed electromagnetic echo signals. A 3D digital model of internal pavement distress was generated using the inverse distance weight and ray-casting methods with trilinear interpolation. Finally, relying on the physical project, cores were extracted to validate the distress model. The method effectively reflects the internal pavement distress, and enables realise the interactive images between the pavement entity and the digital model, which can essentially contribute to the digital twin of pavement systems. [ABSTRACT FROM AUTHOR]

Considering that the decision-making and planning of large-scale highway network under the condition of limited funds, there are some problems such as complex algorithm of feasible solution of maintenance scheme and low efficiency of optimisation process, a heuristic maintenance planning optimisation algorithm based on budget is introduced. This paper focuses on the performance prediction, the determination of treatment measures and the optimisation of the optimal scheme. Firstly, through the analysis of the technical process of prediction and treatment measures, the pavement performance degradation models of pavement condition index, riding quality index and rut depth index based on treatment level are established. Then, based on the characteristics of pavement performance degradation in China, the concept of maintenance benefit based on pavement performance index is proposed, and the cost-benefit optimisation model of highway asphalt pavement is established. A budget-based heuristic algorithm is proposed to solve the optimisation model for maintenance planning with budget constraints. Finally, taking Lian-Xu highway network in a case study, the optimal scheme of treatment measures and fund allocation for the maintenance section of the large-scale highway network is realised under the condition of limited funds, so as to verify the feasibility of the optimisation model. [ABSTRACT FROM AUTHOR]

Porous asphalt concrete (PAC) constitutes large air voids and coarse aggregate, forming a unique aggregate structure. The open pore structure is advantageous in creating space for stormwater runoff to infiltrate into an underground basin and reduce tyre-road noise. However, this aggregate structure compromises the load-carrying capacity and deformation resistance of the mixture. Achieving balance between permeability and bearing capacity of PAC has been a major concern. This study evaluates effects of the aggregate structure on bearing capacity and the deformation resistance of PAC. Gradation-based framework was first applied to examine different gradations of PAC. Discrete-element models of PAC with varying gradations were developed to evaluate its performance and characteristics of aggregate skeleton. A laboratory wheel track test was conducted to validate findings from the DEM analysis. It was found that gradation that meets the interlock check of the framework produced a mixture with optimal performance. More coarse aggregate provides additional strength but lacks sufficient smaller-sized particles to form a new skeleton when it breaks down. More fine aggregate diminishes the load-carrying capacity and deformation resistance of the mixture as no stable skeleton could be formed. [ABSTRACT FROM AUTHOR]

In multiple sclerosis (MS), the imbalance between T helper (Th)-17 cells and regulatory T (Treg) cells are critical in autoimmune central nervous system (CNS) inflammation and demyelination. Experimental autoimmune encephalomyelitis (EAE) is an established mouse MS model and simulates MS at diverse levels. This study aims at investigating the impact of anlotinib on the clinical severity of EAE and CD4+ T cell differentiation. EAE-induced mice were treated with water (control) or 6 mg/kg anlotinib by gavage daily. At the peak of EAE, histopathological examination and flow cytometry analysis of CNS-infiltrating CD4+ T cells were performed. In vitro differentiation of CD4+ T cells under different conditions was detected by flow cytometry and quantitative real-time PCR. Finally, the impacts of anlotinib on the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and the transcription levels of key genes involved in Th17 and Treg differentiation were tested. Anlotinib attenuated the clinical severity of EAE and changed the frequencies of CNS-infiltrating CD4+ T cell subsets. Anlotinib inhibited the differentiation of Th17 cells in vitro, decreased the phosphorylation of STAT3, and reduced the expression of Rorc. Anlotinib promoted the differentiation of Treg cells and upregulated the expression levels of CD39 and CD73. Anlotinib alleviated the symptoms of EAE via inhibiting the Th17 cell differentiation and promoting Treg cell differentiation. Our study provides new opportunities for the exploitation of anlotinib as a therapeutic agent for the treatment of MS. [ABSTRACT FROM AUTHOR]

In this study, we provide a quantitative analysis of prose and verse in the classical Chinese novel, Dream of the Red Chamber (DRC), and discuss the implications for the disputed authorship of the novel. Firstly, we examine the amount of verse in across the chapters of DRC, and compare the style of the verse and prose portions of DRC. Secondly, a Principal Component Analysis (PCA) of DRC is performed based on the prose portions of the novel. Lastly, we discuss the implications of our experimental results for authorship attribution as well as descriptive stylistic analysis of DRC. Our authorial analysis largely confirms the findings of some previous studies that the novel has two authors. Meanwhile, stylistic analyses of the prose portions of the novel yield new and interesting results, which demonstrates that stylometric tools can be used to facilitate descriptive studies of classical Chinese literature. [ABSTRACT FROM AUTHOR]

Polyethylene vinyl acetate (EVA) has been widely investigated and employed as polymeric wax inhibitor (PWI). In this paper, the wax deposition characteristics of synthetic oils with different concentrations of EVA PWI were investigated. The obtained surface and bottom wax deposits were analyzed through differential scanning calorimeter (DSC), polarizing microscope, Fourier transform-infrared spectroscopy (FT-IR) and high-temperature gas chromatography (HTGC). It is found that the EVA PWI could obviously decrease the wax deposition rate and accelerate the aging of wax deposits. Adding the EVA PWI can trigger a novel heterogeneous wax deposit structure, in which the wax appearance temperature and wax content increases continuously from the bottom to the surface layer. Compared to the bottom wax deposit, the surface wax deposit has higher concentrations of both EVA and high carbon number wax molecules (Cn > C25). The formation mechanism of the novel heterogeneous wax deposit structure was explained from two aspects. Firstly, the wax crystal morphology of surface layer is significantly changed from needlelike to diamond-like due to higher temperature and the accumulation of EVA and high carbon number wax molecules in the surface wax deposit, therefore, higher solid wax content is needed for the building of a continuous three-dimensional network structure to resist shearing of pipe flow. Secondly, the lower temperature and larger aspect ratio of wax crystals in the bottom wax deposit are adverse for the diffusion of wax molecules into the bottom wax deposit, thus the aging rate of bottom wax deposit is lower than that of surface layer. [ABSTRACT FROM AUTHOR]

AbstractA micro-rheological integration experiment was conducted on model oils without asphaltene and with 0.05 wt% asphaltene. The study examined the viscosity-temperature characteristics of both model oils under different cooling rates and shear rates. Significant changes were observed in the viscosity-temperature curve of the asphaltene-containing model oil. At low shear rates, a distinct wavelet peak was identified in the temperature range of 37-30 °C, where viscosity initially increased, then decreased, and subsequently increased again. This wavelet peak diminished with the increasing shear rate, eventually forming a “buffer platform”. The underlying mechanism was attributed to asphaltene altering the wax crystal behavior from “uniform precipitation network structure formation” to “formation of unstable large aggregates - dissociation into multiple small stable aggregates - growth into larger stable aggregates.” In addition, the wax precipitation rate remained constant in the model oil without asphaltene, while in the asphaltene-containing model oil, the rate significantly accelerated between 34.5 °C and 32.5 °C. And the asphaltenes promoted the formation of small wax crystal particles but inhibited the growth of wax crystal particles. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the complexity of British culture across the twentieth century. Different from previous studies concerning cultural complexity that used written texts as the experimental data, the present study employed a large data-set of speeches and debates from the British parliament, with the intention of examining the change of British cultural complexity from the perspective of spoken texts. Interestingly, the findings of this study were largely in accordance with those of previous studies that were based on written texts. First, this study confirmed the argument that culture is cumulative in nature. In addition, this study showed that longer N-grams generate higher entropy values. Nonetheless, discrepancies were found in this study, such as the different impacts of crises on the growth of cultural complexity in Britain and America. Furthermore, comparisons with previous studies indicated a lower complexity of British spoken culture than its written counterpart. We have provided possible explanations as well as the implications for future research. [ABSTRACT FROM AUTHOR]

In this study, 20-year and 40-year designs of common pavement types in USA at three traffic levels are examined for their environmental burdens, including hot mix asphalt pavement, jointed plain concrete pavement and continuously reinforced concrete pavement. The study first introduced a previously built life cycle assessment model in pavement engineering and then performed the detailed modelling for each pavement design, with special efforts devoting to the delay estimation of in the congestion module and the usage module (roughness effect on the fuel economy). In the context of this study, regarding the multiple environmental indicators, it is found that 40-year pavement designs do not necessarily carry environmental advantages over their 20-year counterparts, being only possible at ‘high’ traffic volumes. Sensitivity analysis indicates that the influences of stress developing rate, recycling, feedstock energy of asphalt binder and maintenance strategy are less significant compared to that of traffic volume. In the life cycle inventory, material module and usage module are two dominating contributors; share of congestion module due to construction and maintenance activities grows quickly with the increase of traffic volume. [ABSTRACT FROM AUTHOR]

Abstract The precipitation of wax crystals will lead to the formation of gelation structures in waxy crude oils, and the presence of asphaltenes will affect the gelation and flow process of waxy crude oils. In this work, five waxy oils with different asphaltene contents were formulated, and the effect of asphaltene on the gelation and flow behavior of wax-containing simulated oils was investigated. The results show that asphaltenes can improve the low-temperature rheology of wax-containing simulated oils to a certain extent. When the asphaltene contents in wax-containing simulated oils increased from 0 wt% to 0.5 wt%, the pour points decreased from 25 °C to below 0 °C, while the gelation temperatures and storage modulus were also decreased from the initial 29.01 °C to 25.64 °C and 33262 Pa to 5.9 Pa, respectively. The results were due to the fact that the increase of asphaltene contents weakened the gelation network structure strength of wax-containing simulated oils and inhibited gelation process. Meanwhile, in the range of low asphaltene contents, the apparent viscosity of wax-containing simulated oils at 10 °C decreased from 531.5 mPa·s to 7.6 mPa·s with the increase of asphaltene contents. [ABSTRACT FROM AUTHOR]