Evolution of the Critically Endangered Green Sawfish Pristis zijsron (Rhinopristiformes, Pristidae), Inferred from the Whole Mitochondrial Genome.

The green sawfish Pristis zijsron (Bleeker, 1851), a species of sawfish in the family Pristidae (Rhinopristiformes), mainly inhabits the Indo-West Pacific region. In this study, the complete mitochondrial genome of the critically endangered green sawfish is first described. The length of the genome is 16,804 bp, with a nucleotide composition of 32.0% A, 24.8% C, 13.1% G, and 30.0% T. It contains 37 genes in the typical gene order of fish. Two start (GTG and ATG) and two stop (TAG and TAA/T-) codons are found in the thirteen protein-coding genes. The 22 tRNA genes range from 67 bp (tRNA-Ser) to 75 bp (tRNA-Leu). The ratio of nonsynonymous substitution (Ka) and synonymous substitution (Ks) indicates that the family Pristidae are suffering a purifying selection. The reconstruction of Bayesian inference and the maximum likelihood phylogenetic tree show the same topological structure, and the family Pristidae is a monophyletic group with strong posterior probability. Pristis zijsron and P. pectinata form a sister group in the terminal clade. And the divergence time of Rhinopristiformes show that P. zijsron and P. pectinata diverged as two separate species in about Paleogene 31.53 Mya. Complete mitochondrial genomes of all five sawfishes have been published and phylogenetic relationships have been analyzed. The results of our study will provide base molecular information for subsequent research (e.g., distribution, conservation, phylogenetics, etc.) on this endangered group.

Ultrafast Strategy to Fabricate Sulfur Cathodes for High-Performance Lithium-Sulfur Batteries.

Based on the different dielectric properties of materials and the selective heating property of microwaves, the ultrafast (30 s) preparation of S-NiS2@SP@Bitu as a cathode material for lithium-sulfur batteries was achieved using bitumen, sulfur, Super P, and nickel naphthenate as raw materials for the first time, under microwave treatment. NiS2@SP@Bitu forms Li-N, Li-O, Li-S, and Ni-S bonds with polysulfide, which contributes to promoting the adsorption of polysulfide, reducing the precipitation and decomposition energy barrier of Li2S, and accelerating the catalytic conversion of polysulfide, as result of inhibiting the "shuttle effect" and improving the electrochemical performance. S-NiS2@SP@Bitu as the sulfur cathode material demonstrates outstanding rate performance (518.6 mAh g-1 at 4C), and stable cycling performance. The lithium-sulfur battery with a sulfur loading of 4.8 mg cm-2 shows an areal capacity of 4.6 mAh cm-2. Based on the advantages of microwave selective and rapid heating, this method creatively realized that the sulfur carrier material was prepared and sulfur was fixed in it at the same time. Therefore, this method would have implications for the preparation of sulfur cathode materials.

Comparative Analysis of Four Complete Mitochondrial Genomes of Epinephelidae (Perciformes).

Groupers are commercial, mainly reef-associated fishes, classified in the family Epinephelidae (Perciformes). This study first sequenced the complete mitogenomes of Cephalopholis leopardus, Cephalopholis spiloparaea, Epinephelus amblycephalus, and Epinephelus hexagonatus. The lengths of the four Epinephelidae mitogenomes ranged from 16,585 base pair (bp) to 16,872 bp with the typical gene order. All tRNA genes had a typical cloverleaf structure, except the tRNA-Ser (AGY) gene which was lacking the entire dihydrouridine arm. The ratio of nonsynonymous substitution (Ka) and synonymous substitution (Ks) indicated that four groupers were suffering a purifying selection. Phylogenetic relationships were reconstructed by Bayesian inference (BI) and maximum likelihood (ML) methods based on all mitogenomic data of 41 groupers and 2 outgroups. The identical topologies result with high support values showed that Cephalopholis and Epinephelus are not monophyletic genera. Anyperodon and Cromileptes clustered to Epinephelus. Aethaloperca rogaa and Cephalopholis argus assembled a clad. Cephalopholis leopardus, C. spiloparaea, and Cephalopholis miniata are also in a clade. Epinephelushexagonatus is close to Epinephelus tauvina and Epinephelus merra, and E. amblycephalus is a sister group with Epinephelus stictus. More mitogenomic data from Epinephelidae species are essential to understand its taxonomic status with the family Serranidae.

Novel duplication remnant in the first complete mitogenome of Hemitriakis japanica and the unique phylogenetic position of family Triakidae.

In this study, we firstly determined the complete mitogenome of the Japanese topeshark (Hemitriakis japonica), which belong to the family Triakidae and was assessed as Endangered A2d on the IUCN Red List in 2021. The mitogenome is 17,301 bp long, has a high AT content (60.0%), and contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, a control region and specially a 594 bp-long non-coding region between Cytb gene and tRNA-Thr gene. The novel non-coding region share high sequence similarity with segments of the former and latter genes, so it was recognized as a duplication remnant. In addition, the Cytb gene and tRNA-Thr gene tandemly duplicated twice while accompanied by being deleted once at least. This is the first report of mitogenomic gene-arrangement in Triakidae. The phylogenetic trees were constructed using Bayesian inference (BI) and maximum likelihood (ML) methods based on the mitogenomic data of 51 shark species and two outgroups. In summary, basing on a novel type of gene rearrangements in houndshark mitogenome, the possibly rearranged process was analyzed and contributed further insight of shark mitogenomes evolution and phylogeny.

A prospective material for the highly selective extraction of lithium ions based on a photochromic crowned spirobenzopyran.

The recovery of lithium from salt lake brines with a high Mg/Li ratio continues to be a challenge due to the very similar ionic properties of Li+ and Mg2+ in aqueous solutions. Here we develop a novel strategy to extract Li+ based on a sensitive photochromic crowned spiropyran probe with the control of UV light. The probe presents high selectivity for Li+ complexation even in solutions with a high Mg/Li ratio up to 1000. On this basis, a high-stability "spiropyran-crown ether" polymer composite membrane material for the visualization and efficient extraction of trace lithium ions in the complicated system of salt lake brines with high ionic strengths will be constructed in the future.