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The strategy of combining different semiconductor materials is adjudged an effective approach to improve the sensing performances of semiconductor materials. However, the specific synergistic mechanism for the excellent gas‐sensitive performances of composite materials has not been elucidated. Herein, a facile solvothermal method is employed to synthesize SnXTi1‐XO2‐TiXSn1‐XO2 core–shell heterostructures using SnCl4•5H2O and tetrabutyl titanate (TBOT) as raw materials. When the molar ratio of SnCl4•5H2O/TBOT is 1.8/3.0, the afforded composite exhibited the highest gas sensing performances compared with other composites prepared with other molar ratios. The enhanced sensing performance is attributed to the simultaneous incorporation of Sn and Ti ions into each other's lattice, leading to an increase in the density of unsaturated Sn and Ti atoms on the surface. Ultimately, more oxygen vacancies are formed by the unsaturated Sn and Ti atoms, which benefits electron capture and the redox reaction of adsorbed gases. Thus, the concept of increased unsaturated metal atoms and oxygen vacancy resulting from the doping of different metal ions into each other's lattice has deepened the understanding of gas sensing and the catalytic reaction mechanisms. The lattice synergy of different metals provides a pathway for the design of advanced gas‐sensing materials and catalysts. [ABSTRACT FROM AUTHOR]

Summary: Upland cotton (Gossypium hirsutum) is the world's largest source of natural fibre and dominates the global textile industry. Hybrid cotton varieties exhibit strong heterosis that confers high fibre yields, yet the genome‐wide effects of artificial selection that have influenced Upland cotton during its breeding history are poorly understood. Here, we resequenced Upland cotton genomes and constructed a variation map of an intact breeding pedigree comprising seven elite and 19 backbone parents. Compared to wild accessions, the 26 pedigree accessions underwent strong artificial selection during domestication that has resulted in reduced genetic diversity but stronger linkage disequilibrium and higher extents of selective sweeps. In contrast to the backbone parents, the elite parents have acquired significantly improved agronomic traits, with an especially pronounced increase in the lint percentage. Notably, identify by descent (IBD) tracking revealed that the elite parents inherited abundant beneficial trait segments and loci from the backbone parents and our combined analyses led to the identification of a core genomic segment which was inherited in the elite lines from the parents Zhong 7263 and Ejing 1 and that was strongly associated with lint percentage. Additionally, SNP correlation analysis of this core segment showed that a non‐synonymous SNP (A‐to‐G) site in a gene encoding the cell wall‐associated receptor‐like kinase 3 (GhWAKL3) protein was highly correlated with increased lint percentage. Our results substantially increase the valuable genomics resources available for future genetic and functional genomics studies of cotton and reveal insights that will facilitate yield increases in the molecular breeding of cotton. [ABSTRACT FROM AUTHOR]

Na2Ti3O7/C nanofibers are successfully synthesized through an electrospinning process followed by hydrothermal treatment. The unique structure of these one‐dimensional nanofibers with two‐dimensional nanosheets on the surface is presumed to significantly shorten the diffusion routes for both electrons and ions. Meanwhile, the carbon matrix with a certain degree of graphitization can dramatically improve the overall conductivity. As a result, the Na2Ti3O7/C nanofiber electrode reveals an impressive electrochemical capability as the anode material of sodium‐ion batteries. It demonstrates a reversible capacity of 110 mA h g−1 after 500 cycles at a rate of 1 C. Moreover, with almost no capacity degradation, the discharge capacity of the Na2Ti3O7/C nanofiber electrode remains at 58 mA h g−1 after 1500 cycles at the high rate of 50 C. This superior electrochemical performance places the Na2Ti3O7/C nanofibers as an anode material with great promise for sodium‐ion batteries that could be applied in large‐scale energy storage. The unique structure of these one‐dimensional nanofibers with two‐dimensional nanosheets on the surface is successfully synthesized. Large specific surface area can greatly shorten the diffusion routes for both electrons and ions. Besides, the carbon matrix can dramatically improve the overall conductivity. As a result, the anode exhibits excellent electrochemical capability for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Aim: DNA barcoding has been widely applied to species diversity assessment in various ecosystems, including temperate forests, subtropical forests, and tropical rain forests. However, tropical coral islands have never been barcoded before due to the difficulties in field exploring. This study aims at barcoding the flowering plants from a unique ecosystem of the tropical coral islands in the Pacific Ocean and supplying valuable evolutionary information for better understanding plant community assembly of those particular islands in the future. Location: Xisha Islands, China. Methods: This study built a DNA barcode database for 155 plant species from the Xisha Islands using three DNA markers (ITS, rbcL, and matK). We applied the sequence similarity method and a phylogenetic‐based method to assess the barcoding resolution. Results: All the three DNA barcodes showed high levels of PCR success (96%–99%) and sequencing success (98%–100%). ITS performed the highest rate of species resolution (>95%) among the three markers, while plastid markers delivered a relatively poor species resolution (85%–90%). Our analyses obtained a marginal increase in species resolution when combining the three DNA barcodes. Main conclusions: This study provides the first plant DNA barcode data for the unique ecosystem of tropical coral islands and considerably supplements the DNA barcode library for the flowering plants on the oceanic islands. Based on the PCR and sequencing success rates, and the discriminatory power of the three DNA regions, we recommend ITS as the most successful DNA barcode to identify the flowering plants from Xisha Islands. Due to its high sequence variation and low fungal contamination, ITS could be a preferable candidate of DNA barcode for plants from other tropical coral islands as well. Our results also shed lights on the importance of biodiversity conservation of tropical coral islands. Xisha Islands (or Paracel Islands) is a group of tropical oceanic coral islands in South China Sea. These islands host unique flora elements and vegetation comparing to those of the mainland China, the continental islands, and the volcanic islands in the Pacific. Here, we provide the first plant DNA barcode data for this unique ecosystem. Our results strongly suggested that ITS is more powerful in identifying species than other two plastid markers or their combinations. The PCR and sequencing of ITS are more successful in these coral islands than in previous studies of other ecosystems due to lower endophytic fungi contamination in plants from Xisha Islands. The study could be of interests for botanists, island biogeographers, and ecologists. [ABSTRACT FROM AUTHOR]