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• The correlation between the micro-structure aging mechanisms and macroscopic mechanical properties of GAP-based propellant is studied through mesoscopic simulation calculation and several testing methods. • The aging mechanisms include chain breakage of crosslinking networks, decomposition of plasticizers, and dissolution of CL-20 particles. • The macroscopic mechanical properties are effected by the coupling of elastic modulus of the binder matrix and interface strength. • The elastic modulus of the binder matrix effects the change in the elastic modulus of the propellant.The interface strength mainly causes a decrease in the maximum tensile strength, maximum elongation, and dewetting strain. The correlation between the macroscopic mechanical properties and micro-structure of glycidyl azide polymer (GAP)-based solid propellants during aging has been studied. A typical 60 °C–180 d high-temperature accelerated aging experiment on propellants was conducted. The changes in micro-structure were analyzed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), scanning electron microscope (SEM), and component analysis of the plasticizer and stabilizer. Changes in the macroscopic properties were analyzed through uniaxial tensile tests. The experimental results indicated that the micro-structure aging mechanisms of the propellants were the chain breakage of crosslinking networks, decomposition of plasticizers, and dissolution of CL-20 particles. The macroscopic mechanical properties were characterized by a gradual decrease in the maximum tensile strength, maximum elongation, dewetting strain, and elastic modulus during the aging process. Through mesoscopic simulation methods and correlation analysis, the relationship between the macroscopic mechanical properties and micro-structure was further established. The macroscopic mechanical properties of propellants are effected by the coupling of microscopic aging mechanisms. Chain breakage of the crosslinking networks and decomposition of the plasticizers lead to a decrease in the elastic modulus of the binder matrix. The elastic modulus of the binder matrix effects the change in the elastic modulus of the propellant. The dissolution of the CL-20 particles results in a decrease in the interface strength. The interface strength mainly causes a decrease in the maximum tensile strength, maximum elongation, and dewetting strain. These results are important for developing reliable predictive aging models for GAP-based propellant. [ABSTRACT FROM AUTHOR]

Highlights • Based on tunnel fire analysis, the combustion of different pavements is compared and analyzed. • The flame-retardant mechanism and evaluation method of tunnel asphalt pavement are summarized. • The flame-retardant method of tunnel asphalt pavement is summarized. • The development direction of shotcrete in tunnels in cold regions is forecasted. Abstract Though asphalt pavement is widely used in highway tunnels, the flammability of the asphalt pavement is still one significant topic for an in-depth study due to the serious consequences of the tunnel fire. This paper presents a review of the flame retardancy on highway tunnel asphalt pavement. Firstly, the combustion of asphalt pavement and cement pavement is compared on the basis of highway tunnel fire, the commonly used asphalt flame-retardant evaluation standards are analyzed. Secondly, flame-retardant technologies including flame retardant, component flame-retardant method and porous structure flame-retardant method are summarized. Furthermore, the application of nanotechnology in flame-retardant asphalt is reviewed. Finally, concluding remarks and important future investigation directions are presented, which will be advantageous to future study the flame retardancy on highway tunnel asphalt pavement. [ABSTRACT FROM AUTHOR]

Inherited colorectal cancer syndromes increase the risk of contracting colorectal and other cancers. International guidelines recommend the identification of individuals with hereditary colorectal cancer and the supervision of asymptomatic individuals with a family history. However, detection of hereditary colorectal cancer is suboptimal. The prevalence of genetic counselling and testing for individuals with high genetic risk is low. To identify, characterize and summarize patient-targeted interventions on improving the uptake of colorectal cancer genetic evaluation for at-risk individuals and enhancing their informed decision making. Systematic review. Six electronic databases (PubMed, CINAHL, Web of Science, Embase, PsycINFO, and Cochrane library) were searched to identify eligible clinical trials from each database's inception to March 25, 2020. The reference lists of the included studies and reviews were checked for additional articles. Studies were screened and independently appraised by two reviewers using the standardized critical appraisal checklist for randomized controlled trials and quasi-experimental studies from the Joanna Briggs Institute. The results were tabulated and reported in descriptive format. Based on the inclusion criteria, 8 articles satisfied the inclusion criteria and were included. The studies examined patient-targeted intervention strategies related to risk assessment, education, and decision aids. Outcomes included (1) informed decisions regarding microsatellite instability testing, (2) informed decisions concerning genetic testing, (3) genetic counselling and testing. Most of the included studies revealed that interventions had positive effects on the uptake of colorectal cancer genetic evaluation for at-risk individuals and their informed decision making. There were few studies included in this review, and the results were inconsistent. Based on this review, the conclusion cannot be made that interventions for risk assessment, education, and decision aids have positive effects on the uptake of colorectal cancer genetic evaluation for at-risk individuals and their informed decision making. However, to our knowledge, this is the first systematic review to summarize the effectiveness of patient-targeted interventions to inform decision making and improve uptake of colorectal cancer genetic evaluation for at-risk individuals. This review provides important evidence for related topics. Future studies with rigorous designs are recommended. Nurses have a crucial role in personalized health care. The involvement of nurses in collaboration with all the stakeholders in the development, implementation and evaluation of cancer genetic screening programs to improve genetic referral of individual at risk. [ABSTRACT FROM AUTHOR]

The factors that control arsenic (As) mobilization by dissimilatory iron reduction (DIR) are complicated. The association between As mobilization and extracellular polymeric substance (EPS) of dissimilatory iron reducing bacteria (DIRB) remained unclear. In this study, three DIRB were isolated from high arsenic groundwater to understand the effects of EPS on As mobilization. In the laboratory settings, strain Klebsiella oxytoca IR-ZA released As into aqueous phase from As-bearing ferrihydrite, while strain Shewanella putrefaciens IAR-S1 and S. xiamenensis IR-S2 re-sequestrated As by forming secondary minerals during ferrihydrite reduction. Characterization of EPS contents with Fourier Transform Infrared Spectroscopy and high-performance liquid chromatography suggested that mannan and succinic acid were the main different EPS contents of the DIRB. The biomineralization processes were tightly regulated by EPS compositions. Mannan secreted by IAR-S1 and IR-S2 promoted while succinic acid secreted by IR-ZA suppressed the biomineralization and As immobilization. Energy-dispersive X-ray Spectroscopy mapping indicated that As in the secondary minerals was wrapped with EPS. X-ray diffraction and room temperature Mössbauer spectroscopy showed these secondary minerals were vivianite and magnetite, respectively. The amount of As mobilized into aqueous phase was strongly affected by available anions (H 2 PO 4 − and HCO 3 −). Our results indicated that the EPS of DIRB significantly influenced As mobilization. Unlabelled Image • Three indigeous DIRB were found to release and re-sequestrate As, respectively. • EPS was the key factor that influenced As mobilization. • Mannan secreted by strains IAR-S1 and IR-S2 promoted the As immobilization. • Succinic acid by strain IR-ZA suppressed the As immobilization. [ABSTRACT FROM AUTHOR]