Early Miocene Mosses from Weichang, North China, and their Environmental Significance

Twenty-seven moss specimens collected from the Guangfayong section (Early Miocene, 22.1 Ma) of the Weichang District, North China were investigated in the present study. Based on the morphological and anatomical features of gametophytes, all specimens were found to belong to three species: Leptodictyum riparium, Drepanocladus subtrichophyllus sp. nov., and Amblystegium varium, all of which belong to the family Amblystegiaceae. The microhabitats and living environments of fossil mosses were also investigated based on comparison with living mosses. The results suggest that these mosses grew primarily at the edges of rivers, streams, and lakes and favored being submerged in streams or lakes in the Weichang District in the Early Miocene

New Fossil Liverworts from the Lower Cretaceous of Western Liaoning, China

Sixteen liverwort specimens collected from the Lower Cretaceous Yixian Formation of Huangbanjigou Village, Liaoning Province, China are studied in this work. The plants are thalloid and preserved in brown arenaceous mudstone as impressions. Based on examinations, the liverworts are assigned to two new genera and five new species: Riccardiothallus palmata sp. nov., Pallaviciniites stricta sp. nov., Pellites latithallus gen. et sp. nov., Conocephalumites hexagonites gen. et sp. nov. and Metzgerites multifidus sp. nov., belonging to five families and five genera. The fossil research indicates that the divergence of families, Aneuraceae and Metzgeriaceae, Pallaviciniaceae and Hymenophytaceae, Pelliaceae and Fossombroniaceae, was in the Lower Cretaceous (125 Ma). The research provides significant additions to the fossil liverwort records in Western Liaoning and offers fossil evidence for studying the classification and evolution of extant liverworts

Chromosome screening using culture medium of embryos fertilised in vitro: a pilot clinical study

Abstract Background Previous studies from this as well as other research groups suggested that non-invasive chromosome screening (NICS) with embryo culture medium can be used to identify chromosomal ploidy and chromosomal abnormalities. We here report a series of clinical cases utilizing the technology. Methods A total of 45 couples underwent in vitro fertilisation during a period between February 2016 and February 2017. Karyotyping revealed normal chromosomes in both partners in 23 couples, and chromosomal rearrangements in at least one partner in 22 couples. Intracytoplasmic sperm injection (ICSI) was used for fertilization. NICS was carried out using embryo culture medium at the blastocyst stage via multiple annealing and looping-based amplification cycles, whole-genome amplification and next-generation sequencing. Results A total of 413 embryos were obtained; 170 blastocysts were subjected to NICS. The screening showed euploidy in 79 embryos, aneuploidy in 52 embryos, and mosaic ploidy for 33 embryos. The rate of euploidy was comparable in couples with normal karyotype (50.7%; 38/75) vs. chromosomal rearrangement (43.2%; 41/95). A total of 52 euploid embryos (50 oocyte retrieval cycles) were transferred in 43 women. Biochemical pregnancy rate was 72.0% (36/50). Clinical pregnancy rate was 58.0% (29/50). The rate of spontaneous miscarriage was 3/29 (none with chromosomal aneuploidy). A total of 27 healthy babies were delivered. Conclusions NICS could identify embryo chromosomal abnormalities in couples either with or without chromosomal rearrangement, with satisfying clinical outcomes