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Soil has an intricate pore structure, with the macropore structure serving as a pivotal component of gas exchange, liquid flow, and solute transport within the soil matrix. Scientifically understanding the macropore structure is important for the exploration of soil ecological functions. Drawing upon research literature from diverse nations, this study presents a comprehensive summary of past research findings, thoroughly examining the definition and taxonomy of soil macropores. Additionally, we delve into the factors that affect macropore structure, the effects of macropores on soil ecological functions, and the indicators that describe the nature of macropores. Furthermore, the principles, suitability conditions, benefits, and limitations of the widely utilized techniques for characterizing soil macropore structure were outlined, including staining observation, soil water retention curve, mercury intrusion porosimetry, gas adsorption, nuclear magnetic resonance, scanning electron microscopy, and computed tomography (CT). A comparative analysis was conducted to assist scholars in comprehending the theory of soil macropores, facilitating the selection of suitable macropore structure characterization techniques, and enabling the development of collaborative application modes among these techniques. Using the Web of Science core collection database, bibliometric software such as VOSviewer and CiteSpace were employed to explore the research hotspots and trends in CT, which is currently the most popular technique for characterizing soil macropore structure. This analysis offers insights into the future prospects of CT in the field of soil macropore structure characterization techniques. This article is of particular interest to readers engaged in the characterization of soil macropores. [ABSTRACT FROM AUTHOR]

Although studies have reported the modification effect of air pollutants on heat-related health risk, little is known on the modification effect among various particulate matter with different particle size on mortality. We aimed to investigate whether the associations of hot temperatures with daily mortality were modified by different air pollutant levels in Shandong Province, China. Daily data of air pollutants, meteorological factors, and mortality of 1,822 subdistricts in Shandong province from 2013 to 2018 were collected. We used a time-stratified case-crossover model with an interaction term between the cross-basis term for ambient temperature and the linear function of particulate matter ≤1 µm (PM1), PM2.5, nitrogen dioxide (NO2), and ozone to obtain heat-mortality associations during the hot season. Results showed that the cumulative odds ratio of extreme heat on mortality over 0 to 10 days was 3.66 (95% CI: 3.10-4.31). The mortality risk during hot seasons was stronger at high air pollutant levels. The modification effect of particulate matters on heat-related mortality decreased by its aerodynamic diameter. Females and older adults over 75 years were more vulnerable to the modification effect of air pollutants, and significant differences were detected in the association between temperatures and mortality stratified by PM1 and PM2.5. Higher heat-related mortality risks were observed at high NO2 levels, especially for cardiorespiratory disease. The findings suggest that more consideration should be given to the combined effect of very fine particles and NO2 with ambient heat when developing healthcare strategies, and women and older adults should be given priority in health-related settings.

Objective: To investigate the reconstruction of digital three-dimensional (3D) model of normal human placental vascular network based on MRI data in vitro., Methods: Six full term placentas were collected, casted with modified self-curing denture base resin and scanned by T1 e-THRIVE high resolution magnetic resonance imaging. MRI images were imported into Mimics 14.0 software for 3D reconstruction, and the 3D model was compared with placental vascular casting model., Results: (1) The placental vascular network could be obtained on MR 2D images. The 3D model were reconstructed successfully, which showed clear, realistic images. The 3D model could be zoomed and revolved from any direction to observe the branches of arteries and veins. (2) The umbilical vein and 2 umbilical arteries could be seen in the 3D model. In the root of the umbilical cord, the umbilical vein divided into 5-7 branches. While the 2 umbilical arteries anatomoses to form blood sinus and then devided into sub-branches. All the peripheral vessels ended in chorionic plate with abundant sub-branches. (3) When compared with the casting of placental arterial-venous vascular network, the morphology, structure, angle and trend of vessels in 3D model was consistent with the casting network., Conclusions: Reconstruction of digital 3D model of normal human placental vascular network based on MRI in vitro is a new and promising method for the study of placental vasculature. It has better vascular exposure, free rotation, radiation-free. It provides a promising base for the study of placental vasculature in vivo in the future.

Objective: To investigate the distributions of genotypic and allelic frequencies of intercellular adhesion molecule-1 (ICAM-1) gene K469E and platelet endothelial cell adhesion molecule-1 (PECAM-1) gene C373G in patients with preeclampsia., Methods: Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) and DNA sequencing were used for detecting ICAM-1 gene K469E and PECAM-1 gene C373G genotypes in 110 women with preeclampsia and 110 normotensive pregnant women in comparison with their clinical characteristics., Esults: The distributions of observed and expected genotype frequencies were consistent with Hardy-Weinberg equilibrium. No significant differences were found in the genotype and allele frequencies of ICAM-1 gene K469E between the two groups (P>0.05), but the CC and the CG genotype frequencies of PECAM-1 gene C373G were significantly different between them (P<0.05). The relative risk for preeclampsia of CG genotype was 1.959 folds of that in CC genotype carriers (OR=1.959, 95%CI: 1.090-3.520, P=0.024), and this association still existed after adjustment for age, gravidity, parity and BMI in logistic regression models. The C373G allele frequencies showed no significant difference between the two groups (P>0.05)., Conclusions: The CG genotype of PECAM-1 gene C373G genetically predispose the carriers to preeclampsia, while ICAM-1gene K469E polymorphisms is not associated with preeclampsia.