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SUMMARY: Sinapis alba and Sinapis arvensis are mustard crops within the Brassiceae tribe of the Brassicaceae family, and represent an important genetic resource for crop improvement. We performed the de novo assembly of Brassica nigra, S. alba, and S. arvensis, and conducted comparative genomics to investigate the pattern of genomic evolution since an ancient whole‐genome triplication event. Both Sinapis species retained evidence of the Brassiceae whole‐genome triplication approximately 20.5 million years ago (Mya), with subgenome dominance observed in gene density, gene expression, and selective constraint. While S. alba diverged from the ancestor of Brassica and Raphanus at approximately 12.5 Mya, the divergence time of S. arvensis and B. nigra was approximately 6.5 Mya. S. arvensis and B. nigra had greater collinearity compared with their relationship to either Brassica rapa or Brassica oleracea. Two chromosomes of S. alba (Sal03 and Sal08) were completely collinear with two ancestral chromosomes proposed in the Ancestral Crucifer Karyotype (ACK) genomic block model, the first time this has been observed in the Brassiceae. These results are consistent with S. alba representing a relatively ancient lineage of the species evolved from the common ancestor of tribe Brassiceae, and suggest that the phylogeny of the Brassica and Sinapis genera requires some revision. Our study provides new insights into the genome evolution and phylogenetic relationships of Brassiceae and provides genomic information for genetic improvement of these plants. Significance Statement: The genomes of Brassica and Sinapis share evidence of the ancestral whole‐genome triplication event that distinguishes tribe Brassiceae from other lineages within the family Brassicaceae. This is validated through high‐quality genome assemblies of Brassica nigra, Sinapis alba and Sinapis arvensis that also reveal that Sinapis may represent the more ancient lineage. [ABSTRACT FROM AUTHOR]

Key message: Different digenomic Brassica autoallohexaploids were produced from the crosses of three allotetraploids and ancestral diploids and characterized for the cytological behavior of two subgenomes with two and four copies. Interspecific hybridization and allopolyploidization present an important pathway for plant evolution and breeding. In this study, different types of digenomic autoallohexaploids with two or four copies of two subgenomes (AAAACC, AACCCC, AAAABB, BBBBCC, BBCCCC) were synthesized by the crosses between three Brassica allotetraploids and their diploid progenitors and the chromosome doubling, and their meiotic behaviors were analyzed by fluorescence in situ hybridization (FISH). These autoallohexaploids showed some variations in pollen fertility and seed-sets and produced both euploid and aneuploid progenies with some chromosomes lost. Two subgenomes in these autoallohexaploids showed some aberrant pairings and segregations, and the degrees of meiotic regularity were negatively associated with the genome affinities. The chromosomes of the subgenome with four copies formed few quadrivalents with the average number < 2, and mainly paired as bivalents, and majority of the chromosomes from the subgenome with two copies gave the expected bivalents. The different extents of the equal and unequal segregations corresponded to the chromosome pairings. The development and cytological investigation of these autoallohexaploids provide not only the new germplasm for genetic research and breeding but also the new clues for the genome behavior and interplay between these subgenomes with different copies. [ABSTRACT FROM AUTHOR]

Abstract: A novel lanthanide metal-organic framework (MOF), (bpy) [Eu (ip)1.5(H2O)4] (bpy = 4,4′-bipyridine, ip=isophthalate) (1) has been synthesized via hydrothermal method. Single-crystal X-ray analysis reveals that the three-dimensional (3D) network is formed by one-dimensional (1D) chains through hydrogen bonds. The channel regions of the framework are host to neutral 4,4′-bipyridine molecules which serve as guest-templates. These 4,4′-bipyridine molecules do not coordinate to the metal centers but rather show hydrogen bond participation with metal-bound water molecules. The emission spectra show that 1 emits intense sharp red light when it is excited by different wavelength light of the absorption band. [Copyright &y& Elsevier]

• The Ni 2 P/CTF photocatalyst prepared by solid state chemical reduction method. • The H 2 evolution rate for 2.8%Ni 2 P/CTF is almost the same as that of 3.0%Pt/CTF. • The Ni 2 P cocatalysts act as active centers for H 2 evolution of CTF photocatalyst. [Display omitted] The covalent triazine frameworks (CTFs) have recently become a new generation of organic semiconductor for photocatalytic hydrogen production from water splitting because of their great application potentials. However, the CTFs need to be combined with noble-metal-cocatalysts to achieve photocatalytic water splitting. Herein, we reported the noble-metal-free Ni 2 P/CTF composites as an efficient catalyst for photocatalytic hydrogen evolution. With increasing the Ni 2 P alloy loading on the surface of CTF, the photocatalytic activity increases obviously and then decreases gradually, and the highest photocatalytic H 2 evolution rate is achieved for 2.8%Ni 2 P/CTF, which is almost the same as that of 3.0%Pt/CTF photocatalyst. It has been revealed that the Ni 2 P alloy act as a cocatalyst for effectively suppressing the recombination of photogenerated electrons and holes, promoting the separation and migration of the charge carriers, thereby improving the efficiency of photocatalytic H 2 evolution. This work provides a promising strategy for preparation of cheap and stable photocatalytic system based on CTF for efficient photocatalytic hydrogen evolution under visible-light irradiation. [ABSTRACT FROM AUTHOR]

• Brassica rapa and B. oleracea show asymmetrical effects of autopolyploidization on organ size and gene expression. • Genes expression changes in autotetraploid B. rapa and B. oleracea did not show association with genome heterozygosity. • Genes involved in cell wall biosynthesis were significantly changed in enlarged siliques of autoteraploid B. rapa. Autopolyploidization usually accompanied with the enlargement of single organs or even the whole plant. The potential mechanism is still unclear. Here, we investigated the genome heterozygosity and compared the effect of polyploidization on organ size and global gene expression of two Brassica diploids, B. rapa and B. oleracea. Both vegetative and reproductive organs of enlarged size were observed for the aotutetraploid of B. rapa. In sharp contrast, the B. oleracea aotutetraploid did not show increased organ size except for the seeds. Transcriptome analysis in young silique wall revealed significant more differentially expressed genes (DEGs) between autotetraploid and diploid in B. rapa than those in B. oleracea. These DEGs were distributed randomly on chromosomes and did not show association with those heterozygosity regions. Several genes involved in cell wall biosynthesis were significantly up-regulated in aotutetraploid B. rapa which was well consist with the enlarged siliques. Interestingly, two significantly down-regulated FLOWERING LOCUS T (FT) genes were found in silique wall of autotetraploid B. oleracea. These findings indicated autopolyploidization consequence on organ size and gene expression in Brassica was species-specific and organ-specific which might be under genetic control related to the genome structure and composition. [ABSTRACT FROM AUTHOR]

Abstract: A new series of lanthanide metal–organic frameworks, namely, [Ln (L) (bpdc)0.5 (phen)]∞ (Ln=Eu (1), Gd (2), Tb (3), Dy (4); L =4,4′-bis(2-sulfonatostyryl)biphenyl; bpdc=4,4′-biphenyldicarboxylate; phen=1,10-phenanthroline), has been synthesized hydrothermally from the self-assembly of the lanthanide ions (Ln3+) with the fluorescent whitener disodium 4,4′-bis(2-sulfonatostyryl)biphenyl (Na2 L), the 4,4′-biphenyldicarboxylic acid (H2bpdc) and 1,10-phenanthroline. All of them were characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis and single-crystal X-ray diffraction. To the best of our knowledge, this is the first time to use the Na2 L to synthesize LMOFs in coordination bonds binding fashion. Structural analyses reveal that all four complexes have isostructural three-dimensional (3D) net-structures. Complexes 1–4 display intriguing fluorescent properties and the photoluminescent properties of 1 were discussed in detail. [Copyright &y& Elsevier]

As the first legally binding global agreement on climate change, the Paris Agreement aims to limit long-term global warming to less than 2 °C, preferably below 1.5 °C compared to pre-industrial levels. Road transport, as one of the primary sources of energy consumption and carbon emissions, has great potential for energy conservation and emission reduction in achieving the climate goals. However, current approaches cannot efficiently reduce road travel, making it challenging to decarbonize in the transport sector. Therefore, in this paper, we propose STRICTs, a blockchain-enabled motor vehicle restrictive and trading system based on the carbon emissions cap. STRICTs allows automated carbon emission auditing and carbon emission violation punishment without relying on third-party escrow. Through a decentralized enforcer, STRICTs also enables carbon permit trading reliably and transparently. Finally, we implement a proof-of-concept prototype of the system based on Hyperledger Fabric and conduct experiments for comprehensive performance evaluation through CO2 Emission by Vehicles dataset. The experiment results show the practically affordable performance of STRICTs. [Display omitted] • Carbon emission calculation and carbon emission permit allocation method is developed. • Vehicle data chain is built to guarantee the reliability and correctness of collected vehicle data. • Restrictions on carbon emission allowance is presented to reduce carbon emissions. • A smart-contract-based decentralized enforcer is proposed to audit user's carbon emission behavior. [ABSTRACT FROM AUTHOR]