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This study employed fiber and geopolymer to enhance the engineering performance of coarse-grained fillers. By conducting a series of comparative mechanical tests, the ideal mass mixing ratio design of geopolymer and fiber was investigated first. Then, the influence of rock block content on the mechanical properties of coarse-grained fillers stabilized with fiber and geopolymer was explored. The deformation damage characteristics of fiber- and geopolymer-stabilized coarse-grained fillers with different rock block contents were also discussed in the final test. The results show that the ideal mass mixing ratio of geopolymer for coarse-grained filler stabilization was 15% of dry fine-grained soil in weight and the ideal dosage and length of fiber was 0.4% of dry fine-grained soil in weight and 1.2 × 10−2 m. The compressive strength of fiber- and geopolymer-stabilized coarse-grained fillers shows a tendency to increase first, then decrease, and then re-increase with the increase in rock block contents. The best compressive strength and resistance to deformation were achieved when the rock block content was 30%. The failure mode of fiber- and geopolymer-stabilized coarse-grained fillers translated from shearing slip to vertical splitting as the rock block content increased. This study can provide a reference and support for the engineering application of coarse-grained fillers stabilized with fiber and geopolymer. [ABSTRACT FROM AUTHOR]

Objective: To explore the genetic characteristics of three fetuses with regions of homozygosity (ROH)., Methods: Three fetuses with ROH diagnosed at Nanjing Drum Tower Hospital on December 2, 2020, March 19, 2021, and May 27, 2022, respectively were selected as the study subjects. Clinical data of the fetuses were collected. Chromosomal microarray analysis (CMA) was used to detect the ROH, and tandem repeat sequences (STR)-based multiplex PCR assay was used to identify the mosaicism status in fetus 1., Results: Partial maternal isodisomy (iUPD) (16) was found in fetus 1, for which trisomy rescue may be accountable. Meanwhile, the fetus also has confined placental mosaicism (CPM) but not true mosaicism. The formation mechanism of ROH for fetus 2 was identity by descent. Partial maternal iUPD (7) was found in fetus 3, which may be due to gametic recombination., Conclusion: The ROH of the three fetuses were inherited from both parents or the mother. Above findings suggested that it is justified to detect ROH on imprinting disorder-related chromosomes when potential uniparental disomy is suspected.

Objective: To explore the clinical manifestations of two fetuses harboring heterozygous deletions of the SHOX gene., Methods: Two pregnant women who had presented at the Prenatal Diagnosis Center of Nanjing Drum Tower Hospital respectively on June 24, 2022 and July 27, 2022 were selected as the study subjects. In case 1, prenatal ultrasonography had shown short femur and intrauterine growth retardation of the fetus. Case 2 had a history of spontaneous abortions due to structural chromosomal aberrations. Fetus 1 had undergone a test for the FGFR3 gene, and both fetuses were subjected to single nucleotide polymorphism-based microarray (SNP array) analysis., Results: After excluding the influence of FGFR3 gene variant, fetus 1 was found to harbor a heterozygous 883 kb deletion at Xpter or Ypter, whilst fetus 2 was found to harbor a 5.75 Mb deletion in the Xpter region. Both deletions have encompassed the SHOX gene. The origin of the deletion in fetus 1 was unknown, whilst that in fetus 2 was inherited from its mother. Fetus 1 has been delivered at term with a normal phenotype, and fetus 2 was not born yet., Conclusion: The intrauterine and postnatal phenotypes of fetuses may be predicted by combining the ultrasound finding, parental phenotype and results of CMA, and the results can facilitate genetic counseling and decision making over the pregnancy.