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The use of native vegetation in the coastal regions of Australia has become increasingly popular for stabilising railway corridors built over expansive clays and compressive soft soils. The tree roots provide three stabilising functions: (a) they reinforce the soil; (b) they dissipate excess pore pressures; and (c) they establish sufficient matric suction to increase the shear strength. The matric suction generated within the tree root zone propagates radially into the soil matrix, as a function of the moisture content change. Considering soil conditions, the type of vegetation and atmospheric conditions, a mathematical model for the rate of root water uptake is developed. A conical shape is considered to represent the geometry of the tree root zone. Based on this model for the rate of root water uptake, the pore water pressure distribution and the movement of the ground adjacent to the tree are numerically analysed. Field measurements taken from the previously published literature are compared with the authors' numerical predictions. It is found that, given the approximation of the assumed model parameters, the agreement between the predicted results and field data is still promising. The study indicates that native vegetation improves the shear strength of the soil by increasing the matric suction, and also curtails soil movements. [ABSTRACT FROM AUTHOR]

Background: Anencephaly is a fatal congenital anomaly characterized by the absence of brain hemispheres and cranial arch. Timely preventive measures can be taken by knowing the exact prevalence of this common neural tube defect; thus, carried out through systematic review and meta-analysis, the present study was conducted to determine the worldwide prevalence, incidence and mortality of anencephaly., Methods: Cochran's seven-step instructions were used as the guideline. Having determined the research question and inclusion and exclusion criteria, we studied MagIran, SID, Science Direct, WoS, Web of Science, Medline (PubMed), Scopus, and Google Scholar databases. Moreover, the search strategy in each database included using all possible keyword combinations with the help of "AND" and "OR" operators with no time limit to 2021. The I 2 test was used to calculate study heterogeneity, and Begg and Mazumdar rank correlation tests were employed to assess the publication bias. Data were analyzed by Comprehensive Meta-Analysis software (Version 2)., Results: In this study, the statements of Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) were used. In the first stage, 1141 articles were found, of which 330 duplicate studies were omitted. 371 articles were deleted based on the inclusion and exclusion criteria by reviewing the title and abstract of the study. 58 articles were removed by reviewing the full text of the article because it was not relevant to the research. 360 studies with a sample size of 207,639,132 people were considered for the meta-analysis. Overall estimate of the prevalence, incidence and attenuation of anencephaly worldwide were 5.1 per ten thousand births (95% confidence interval 4.7-5.5 per ten thousand births), 8.3 per ten thousand births (95% confidence interval 5.5-9.9 per ten thousand births), 5.5 per ten thousand births (95% confidence interval 1.8-15 per ten thousand births) respectively the highest of which according to the subgroup analysis, belonged to the Australian continent with 8.6 per ten thousand births (95% confidence interval 7.7-9.5 per ten thousand births)., Conclusion: The overall prevalence of anencephaly in the world is significant, indicating the urgent need for preventive and treating measures., (© 2022. The Author(s).)