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BackgroundPancreatic cancer (PC) is a malignant tumour with poor prognosis and high mortality, and high fasting plasma glucose (HFPG) is considered to be one of its important risk factors.MethodsPC disease burden data were obtained from the Global Burden of Disease Study 2021 (GBD 2021) database. Annual percent change (APC), average APC (AAPC), and 95% confidence interval (95% CI) were analysed using joinpoint linkpoint regression models to assess the trend of PC burden of disease between 1990 and 2021. An age-period-cohort model was used to estimate the independent effects of age, period, and cohort on PC burden, and data on PC mortality attributable to HFPG in China from 2022 to 2032 were analysed on the basis of a Bayesian age-period-cohort model projection.ResultsThe number of Pc deaths due to HFPG continue to rise in China from 1990 to 2021, with age-standardised mortality (ASMR) and age-standardised disability-adjusted life-year rates with increasing AAPC values of 1.12% (95% CI, 0.73–1.52) and 1.00% (95% CI, 0.63–1.37), respectively. Throughout the study, we found that the overall level of PC disease burden was significantly higher in men than that in women. In age-period-cohort analyses, the age effect of PC showed an increasing and then decreasing trend, the period effect showed an overall increasing trend during the study period, and the cohort effect showed an overall slow decreasing trend. In addition, the BAPC model predicted that ASMR is expected to decline significantly in both men and women from 2022 to 2032.ConclusionsIt was found that PC attributable to HFPG was generally on the rise in China from 1990 to 2021 and has been on the decline in recent years, and projections suggest that the country’s future PC disease burden will continue to show a downward trend. Age and period of birth are the main factors affecting the disease burden, especially in men and older age groups. Early prevention, regular screening, and research into the pathogenesis of PC have, therefore, become particularly important.

The pavement bending deformation resistance of the existing macadam base structure is poor. The geogrid-reinforced macadam base can effectively strengthen the bending resistance of the pavement, but no international consensus has been reached at present over bending failure laws of reinforced macadam base structure. Discrete element models of semi-rigid base pavement structure, macadam base pavement structure, and geogrid-reinforced macadam base pavement structure were built based on MATDEM discrete element simulation program; loading calculation of the three models was conducted by taking their centers as loading positions; and model displacement nephogram, strain nephogram, and effects of different spans on their bending deformation were analyzed to reveal bending failure laws of reinforced macadam base and improvement effect of the geogrid on the anti-bending performance of the macadam structural layer. Finally, bending deformation laws of the three pavement structures and improvement effect of geogrid reinforcement on bending properties of the macadam base structure were established. The results show that under bending deformation of semi-rigid base, the vertical strain at the contract surface between the baseplate and soil base and horizontal strain at midspan position reach the maximum, which can easily lead to fracture and shear failure, and the macadam base layer can effectively isolate the tensile strain transmitted from bottom up. Through their own deformation, grids can transform surface pressure load into frictional resistance at the geogrid/soil interface and partial kinetic energy in the system into their own elastic potential energy to reduce the kinetic energy at the subbase layer. Geogrid reinforcement can improve the nonlinearity of macadam materials, reduce the fluctuation amplitude of the strain curve and displacement curve, lengthen the service life of the macadam base pavement structure, and improve its structural soundness under bending deformation. This study can provide a theoretical reference for numerical simulation of bending failure of geogrid-reinforced macadam base.

Existing macadam base structures have poor resistance to bending deformation of pavement. The structural layer is challenged with serious cracking due to the long-term dynamic loads. Despite these issues, however, studies on reinforcement techniques for macadam base structure have been scarce. No reasonable and feasible method on how to improve the bending resistance of flexible base structures (e.g. macadam base structure) and prolong their bending fatigue life has yet been reported. Thus, this study proposed a method for reinforcing macadam base structures with geogrids to strengthen bending performance, anti-fatigue performance and dynamic stability of flexible base structures under different loading levels. The reinforced macadam base structure was investigated through a laboratory test of flexural-tensile strength and a three-point fatigue bending test. A cyclic loading test of reinforced and non-reinforced girder specimens was carried out under five stress levels. The effect of such a new reinforcement method in improving the bending fatigue properties of macadam base structures was analyzed by comparing the yield curves and fatigue lives of reinforced and non-reinforced specimens under different loading levels. Results demonstrate that the non-reinforced macadam base has poor bending resistance. The yield curve and fatigue life of non-reinforced specimens attenuated quickly as it approached the ultimate loading level. Non-reinforced specimens have low-cycle fatigue failures when the loads reach the 0.8 stress level and the ultimate displacement at failure is relatively small, accompanied by obvious failure surface. After geogrids are added, the fatigue life of specimens improved significantly. The yield curve shows no significant attenuation at a high loading level. The reinforced specimens can still maintain high-cycle fatigue failure under the 0.8 stress level and avoid the occurrence of low-cycle fatigue failures. Moreover, reinforced specimens can inhibit transmission of reflection cracks at midspan of cement-stabilized macadam base, delay the propagation of oblique shearing fractures close to the support, and strengthen the dynamic stability and durability of pavement structure with a macadam base. The conclusions of this study provide theoretical references to practical engineering applications of such new reinforcement technology for macadam bases.

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The cold recycling of asphalt pavement has gradually become an important tool for maintenance and reconstruction of old roads because of its economic and environmental characteristics, but it's difficult to evaluate the practical application effect of cold recycling technology due to the lack of macro-level analysis of the performance of the cold recycled pavement. To comprehensively analyze the condition of road network-level cold recycled asphalt pavement (RAP) and evaluate the value of cold recycling technology promotion, in this study the performance indexes of cold recycling technology for asphalt pavement were comprehensively analyzed, the performance and change law of cold RAP were macroscopically predicted, the evaluation index (CRPI) and road network-level fuzzy prediction evaluation system of cold recycled pavement were proposed, and the pavement surface condition index(PCI), riding quality index(RQI), rutting depth index(RDI), and pavement structural strength index (PSSI) were selected as macroscopic evaluation indexes of road network-level cold recycling pavements. Combined with the improved analytic hierarchy process, the weight of the selected index was assigned, and the evaluation levels were divided into three standards: superior, medium, and poor. Finally, based on the C# programming language, combined with grey prediction model and integral algorithm, a fuzzy prediction and evaluation system for the performance of road network-level cold RAP was developed, and the reliability of the prediction was verified based on the actual measurement data. Results show that in the network-level fuzzy prediction and evaluation system of cold RAP technology, the weights of PCI, RQI, QDI, and PSSI are assigned as 0.20, 0.07, 0.20, and 0.53. The predicted value of the performance prediction system for cold RAP has a good correlation with the actual test value, and the relative error is small. The system can obtain the evaluation curve of each index and calculate the comprehensive performance score, and realize the prediction of the overall development trend of cold RAP performance. It shows that the system can analyze and predict the performance of cold RAP at the macro-level. Conclusions of this study provide index system and system support for the macroscopic analysis of cold RAP performance, and also provide reference for related research work. [ABSTRACT FROM AUTHOR]

Cold central-plant recycling (CCPR) is a technical method for the repair and maintenance of old asphalt pavement. However, this method lacks a complete evaluation system. In this study, various influencing factors were investigated and analyzed to establish a comprehensive and systematic evaluation system for CCPR pavement. A full-life staged evaluation system for CCPR pavement was established from perspectives of old pavement investigation and design, construction technology, management, and pavement performance and benefits. This evaluation system covered 5 level-1 indexes, 19 level-2 indexes, and 30 level-3 indexes, which were introduced in the present study. Weights of different indexes were determined by combining various evaluation methods, such as improved analytic hierarchy process and fuzzy comprehensive evaluation, and mutual influences of indexes. The CCPR pavement was evaluated based on the G316 repair and maintenance projects in Hanzhong of Shaanxi Province of China in 2017. Results demonstrate that the performance and benefits of CCPR pavement have the highest weight. Three level-1 indexes, namely, old pavement investigation and design, construction technology, and pavement performance, are evaluated to be good, while benefits and management are excellent. The overall evaluation score is 84.8, and the overall grade is good. The evaluation results conform to practical engineering situations. The proposed evaluation system can provide references to evaluate CCPR pavement. [ABSTRACT FROM AUTHOR]