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BackgroundEpidemiological studies have provided inconsistent evidence of the association between parity and metabolic syndrome (MetS) risk. We conducted this first systematic review and meta-analysis to comprehensively and precisely quantify this topic.MethodsComprehensive searches of PubMed, Embase, and the Web of Science databases were conducted to identify observational studies of the association between parity and MetS risk up to 30 January 2022. Study inclusion, data extraction, and quality assessment were checked and reviewed by two investigators independently. Random-effects models were applied to estimate pooled odds ratios (ORs) and 95% CIs. This study has been registered with PROSPERO.ResultsTwo high-quality cohorts and thirteen medium-quality cross-sectional studies involving 62,095 women were finally included. Compared with the nulliparous, the pooled OR of MetS for the ever parity was 1.31 (95% CI = 0.91–1.88, I2 = 72.6%, n = 3). Compared with the lowest parity number, the pooled OR of MetS for the highest parity number was 1.38 (95% CI = 1.22–1.57, I2 = 60.7%, n = 12). For the dose-response analysis, the pooled OR of MetS for each increment of one live birth was 1.12 (95% CI = 1.05–1.19, I2 = 78.6%, n = 6). These findings were robust across subgroups and sensitivity analyses. No evidence of heterogeneity between subgroups was indicated by meta-regression analyses.ConclusionThe findings suggested that parity was associated with an increased risk of MetS. A sufficient number of large prospective cohort studies are required to fully verify our findings.Systematic Review Registration[https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42022307703].

Considered the temperature distress forms and the impacts of temperature on asphalt pavement, three temperature thermoregulations were proposed to solve the asphalt pavement temperature problems initiatively. Based on the properties of phase change thermoregulation agent, thermoregulation types of composite phase change materials (CPCMS) were studied and the values of appropriate phase change temperature were determined by differential scanning calorimetric (DSC) test. Results show that for high temperature thermoregulation, the phase change temperature range is 35–50 °C, in which with the 58# paraffin proportion increasing, the phase change enthalpy increases linearly and the phase change temperature grows exponentially. As for the low temperature thermoregulation, the phase change temperature range is −5 °C to 5 °C, in which with the Tetradecane proportion increasing, the phase change enthalpy grows linearly, while phase change temperature increases exponentially. In terms of the mixing temperature thermoregulation, the phase change temperature range is 5–35 °C, in which when Tetradecane mass ratio are fixed as 30%, 40%, and 50%, with the 58# paraffin proportion increasing, high temperature enthalpy grows and phase change temperature increases linearly; when 58# paraffin mass ratio are fixed as 30%, 40%, and 50%, with the Tetradecane proportion increasing, low temperature enthalpy grows approximate linearly, exothermic (endothermic) high phase change temperature decreases (grows) slight linearly. Finally, this paper recommends composites mass proportion to different thermoregulations types and the corresponding enthalpy values, which intends to solve the worldwide problem of temperature distresses in asphalt pavement in the future.

A phase change material (PCM) has a significant capacity to store thermal energy. Because of the complex and tough environment of a highway such as traffic load, drainage, and ultraviolet light, the recent studies on PCM cannot be directly applied to highway construction. The composite shape-stabilized phase change material (CPCM) was prepared by using a membrane layer to encapsulate the PCM to ensure stability. Preparation of the CPCM in highway construction discussed in this research includes: (a) CPCM material properties, (b) proper proportioning for preparing the CPCM by Scanning Electronic Microscope (SEM), Differential Scanning Calorimetric (DSC) and the orthogonal test. CPCM was developed using Teradecane, silica, Ethyl Cellulose (EC) and a dispersant. Performance of the CPCM due to the influence of EC and a dispersant also studied to determine exact proportions used in the CPCM. The optimized ratio of Teradecane, silica, EC and dispersant is 1:1:0.1:0.1. Phase change enthalpy of the PCM was calculated to be 178 J/g and the phase change temperature was determined to be 5.8 °C.

Using the finite element method, influences of vehicle load, subgrade fillings and compactness on the subgrade work zone were analyzed, of which the traffic load impacts most. Considering the traffic and mechanical character of the subgrade, it is determined that the appropriate subgrade work zone depth of rural highway is 1.0m. As a result, applying proper work zone depth plays an important role in the construction cost of rural highway.

Concrete interlocking block pavement is characterized of preferred durability, easy construction and maintenance and low construction cost. It can be widely applied in the rural highway. Based with the project of rural highway in Tongchuan Shaanxi province, the paper studies the mechanism of interlocking blocks, design of the pavement, and construction technology for field application. After one year service for open traffic, the interlocking block pavement is shown to have fascinating economy and service performance for the rural road.