A cyclical switch of gametogenic pathways in hybrids depends on the ploidy level.

The cellular and molecular mechanisms governing sexual reproduction are conserved across eukaryotes. Nevertheless, hybridization can disrupt these mechanisms, leading to asexual reproduction, often accompanied by polyploidy. In this study, we investigate how ploidy level and ratio of parental genomes in hybrids affect their reproductive mode. We analyze the gametogenesis of sexual species and their diploid and triploid hybrids from the freshwater fish family Cobitidae, using newly developed cytogenetic markers. We find that diploid hybrid females possess oogonia and oocytes with original (diploid) and duplicated (tetraploid) ploidy. Diploid oocytes cannot progress beyond pachytene due to aberrant pairing. However, tetraploid oocytes, which emerge after premeiotic genome endoreplication, exhibit normal pairing and result in diploid gametes. Triploid hybrid females possess diploid, triploid, and haploid oogonia and oocytes. Triploid and haploid oocytes cannot progress beyond pachytene checkpoint due to aberrant chromosome pairing, while diploid oocytes have normal pairing in meiosis, resulting in haploid gametes. Diploid oocytes emerge after premeiotic elimination of a single-copied genome. Triploid hybrid males are sterile due to aberrant pairing and the failure of chromosomal segregation during meiotic divisions. Thus, changes in ploidy and genome dosage may lead to cyclical alteration of gametogenic pathways in hybrids.

Hierarchically Nanostructured 1D Conductive Bundle Yarn-Based Triboelectric Nanogenerators.

Wearable 2D textile platforms are the subject of intense focus to promote the creation of outstanding added value for textile-based applications in consumer electronics, energy harvesting, and storage. In particular, 2D textile-based energy harvesters from the living environment of human motions exhibit insufficient geometry deformation and low current density, thereby providing low power generation. Therefore, a unique starting point in this work is the use of 1D conductive bundle yarn (1D CBY) as a generic step for the development of 1D CBY-based energy harvesters through a weaving technology. The performance of 1D CBY-based triboelectric nanogenerators (1D CBY-TENGs) is addressed through contact electrification between the arrays of nanostructured 1D CBYs and 2D conductive fabric serving as tribomaterials. The manipulation of hierarchically nanostructured surfaces on the 1D CBYs by the hydrothermal process represents one of the crucial approaches of enhancing power generation through a large contact surface area. The 1D CBY-TENGs with a variation in the number of 1D CBY and stack configurations are also tested as a simple integration scheme, confirming the expected 1D CBY number and stack dependency in the output performance.