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Argali stands as the largest species among wild sheep in Central and East Asia, with a concerning rate of decline estimated at 30%. The intraspecific taxonomy of argali remains contentious due to limited genomic data and unclear geographic separation. In this study, we constructed a chromosome-level genome assembly and annotation for the Tibetan argali (O. a. hodgsoni), together with population genomic resequencing of 32 individuals representing four subspecies. The contig-level genome was 2.64 Gb in size, with a contig N50 length of 71.69 Mb and an estimated genomic completeness of 96.01%. Using Hi-C sequencing data scaffolding, 99.90% of initially assembled sequences were mapped and oriented onto 28 pseudo-chromosomes except the Y chromosome. Annotation uncovered 21,564 protein-coding genes and 46.38% repeat sequences. The average coverage of the population resequencing data was 23.74 with mean mapping ratio up to of 97.19%. The high-quality genome assembly and annotation of the Tibetan argali, coupled with the high-depth population genomic data, will serve as a valuable genetic resource for studies on the taxonomy and conservation of argali. [ABSTRACT FROM AUTHOR]

The evolutionary direction of gonochorism and hermaphroditism is an intriguing mystery to be solved. The special transient hermaphroditic stage makes the little yellow croaker (Larimichthys polyactis) an appealing model for studying hermaphrodite formation. However, the origin and evolutionary relationship between of L. polyactis and Larimichthys crocea, the most famous commercial fish species in East Asia, remain unclear. Here, we report the sequence of the L. polyactis genome, which we found is ~706 Mb long (contig N50 = 1.21 Mb and scaffold N50 = 4.52 Mb) and contains 25,233 protein‐coding genes. Phylogenomic analysis suggested that L. polyactis diverged from the common ancestor, L. crocea, approximately 25.4 million years ago. Our high‐quality genome assembly enabled comparative genomic analysis, which revealed several within‐chromosome rearrangements and translocations, without major chromosome fission or fusion events between the two species. The dmrt1 gene was identified as the male‐specific gene in L. polyactis. Transcriptome analysis showed that the expression of dmrt1 and its upstream regulatory gene (rnf183) were both sexually dimorphic. Rnf183, unlike its two paralogues rnf223 and rnf225, is only present in Larimichthys and Lates but not in other teleost species, suggesting that it originated from lineage‐specific duplication or was lost in other teleosts. Phylogenetic analysis shows that the hermaphrodite stage in male L. polyactis may be explained by the sequence evolution of dmrt1. Decoding the L. polyactis genome not only provides insight into the genetic underpinnings of hermaphrodite evolution, but also provides valuable information for enhancing fish aquaculture. [ABSTRACT FROM AUTHOR]

The crystal structure, three-dimensional Young's modulus projection and band structure of Ba 2 AsXO 6 (X = V, Nb, Ta). [Display omitted] • The double perovskite oxides basic properties of Ba 2 AsXO 6 (X = V, Nb, Ta) are predicted via first-principles. • The theoretical calculation shows that these materials satisfy the stuctural, thermodynamic and mechanical stability. • The results show that they are potential photoelectric and thermoelectric materials. • This paper can provide a theoretical reference for the further study of Ba 2 AsXO 6 (X = V, Nb, Ta). In this paper, the structural, mechanical, electronic, optical and thermodynamic properties of Ba 2 AsXO 6 (X = V, Nb, Ta) double perovskite oxides have been studied based on the first principles of density functional theory. By calculating some parameters such as Goldsmith's tolerance factor (t G), octahedral factor (µ), Bartel's tolerance factor (τ), formation energy, binding energy and elastic constants, it is found that these double perovskite oxides have the potential for stable existence. In addition, Ba 2 AsXO 6 (X = V, Nb, Ta) is an anisotropic material, in which Ba 2 AsVO 6 is brittle, Ba 2 AsNbO 6 and Ba 2 AsTaO 6 are ductile. The electronic properties of the materials show that Ba 2 AsVO 6 and Ba 2 AsNbO 6 are indirect bandgap semiconductors with a band gap of 1.676 eV and 2.654 eV respectively, while Ba 2 AsTaO 6 is direct bandgap semiconductor with a band gap of 3.252 eV. The optical properties revealed that these perovskites exhibit favorable far-ultraviolet light absorption characteristics. The thermodynamic properties show that the specific heat capacity of these double perovskite oxides reaches the Dulong-Petit limit at around 800 K. These results indicate that Ba 2 AsXO 6 (X = V, Nb, Ta) double perovskite oxides have broad application prospects in the fields of thermoelectricity and optoelectronics. Furthermore, these results also provide a valuable theoretical basis for their future experimental synthesis. [ABSTRACT FROM AUTHOR]

This paper employs first-principles calculations to comprehensively investigate the structural, dynamic, electronic, mechanical, and optical properties of A 2 BH 6 (A = K, Rb; B Ge, Sn) perovskite hydrides. Mechanical, thermodynamic, and dynamic stabilities are confirmed through calculations of elastic constants, formation energies, and phonon dispersion. The B/G ratio, below 1.75, indicates a brittle nature and a preference for covalent bonding. Electronic property analysis reveals that these hydrides are indirect band gap semiconductors with band gap values of 1.897 eV, 2.468 eV, 2.129 eV, and 2.657 eV, respectively. Optical property studies demonstrate high ultraviolet absorption. A key focus of this study is the gravimetric hydrogen storage capacities, which are found to be 3.84 wt% for K 2 GeH 6 , 2.97 wt% for K 2 SnH 6 , 2.48 wt% for Rb 2 GeH 6 , and 2.09 wt% for Rb 2 SnH 6. These findings not only enrich the research on the physical properties of perovskite hydrides but also provide an important theoretical basis and new options for the development of efficient hydrogen storage materials. The crystal structure, hydrogen storage capacity and band gap value of A 2 BH 6 (A = K, Rb; B Ge, Sn). [Display omitted] • A 2 BH 6 (A = K,Rb; B Ge,Sn) perovskite has been investigated using first-principles. • A 2 BH 6 (A = K, Rb; B Ge, Sn) exhibits thermodynamic, mechanical and dynamical stability. • A 2 BH 6 (A = K, Rb; B Ge, Sn) is a medium width indirect band gap semiconductor. • A 2 BH 6 (A = K, Rb; B Ge, Sn) has a hydrogen storage capacity of 2.09 W% to 3.84 W%. • The desorption temperature is found to be 221.1 K for K 2 SnH 6. [ABSTRACT FROM AUTHOR]