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RNA viruses are diverse components of global ecosystems. The metagenomic identification of RNA viruses is currently limited to those with sequence similarity to known viruses, such that highly divergent viruses that comprise the "dark matter" of the virosphere remain challenging to detect. We developed a deep learning algorithm – LucaProt – to search for highly divergent RNA-dependent RNA polymerase (RdRP) sequences in 10,487 global meta-transcriptomes. LucaProt integrates both sequence and structural information to accurately and efficiently detect RdRP sequences. With this approach we identified 180,571 RNA viral species and 180 superclades (viral phyla/classes). This is the broadest diversity of RNA viruses described to date, including many viruses undetectable using BLAST or HMM approaches. The newly identified RNA viruses were present in diverse ecological niches, including the air, hot springs and hydrothermal vents, and both virus diversity and abundance varied substantially among ecological types. We also identified the longest RNA virus genome (nido-like) observed so far, at 47,250 nucleotides, and expanded the diversity of RNA bacteriophage to more than ten phyla/classes. This study marks the beginning of a new era of virus discovery, with the potential to redefine our understanding of the global virosphere and reshape our understanding of virus evolutionary history.

The surface modification strategy is widely used to solve the problems of low stability, agglomeration, surface oxidation and photoluminescence quenching of quantum dots (QDs) in practical applications. However this method can easily destroys the surface ligands of QDs, increases defects even leads to a huge loss of fluorescence. In order to improve the stability of QDs, a new synthesis method of QD-silica hybrid nanospheres was proposed in this study. These QD-silica hybrid nanospheres are characterized by using mesoporous silica spheres (MSSs) as template, adsorbing QDs as one shell, and then coating a silica layer as another shell (named SQS). The template MSSs were functionalized by (3-mercaptopropyl) trimethoxysilane (MPTMS) in order to connect MSSs and QDs. After that, the QD-adsorbed silica spheres were coated with silica as the encapsulation layer by Stober method. The structure and morphology of SQS were analyzed by TEM. The effects of different contents of MPTMS and tetraethoxysilane(TEOS) were experimentally compared. Finally, it was found that the optimal contents of MPTMS and TEOS was 250μL and 1.5mL, respectively. The luminescence intensity of SQS samples could reach 2 times higher than that of pure QD solution. Meanwhile, SQS hybrid nanospheres could avoid the tiny spots inside the microstructure caused by QD aggregation and play a better role in dispersion.

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