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In consideration of the severe hazards of radioactive uranium pollution, the rapid assessment of uranium in field and in vivo are urgently needed. In this work a novel biocompatible and sensitive visual fluorescent sensor based on aggregation-induced emission (AIE) was designed for onsite detection of UO

Soybean mosaic virus (SMV) is widely recognized as a highly damaging pathogen of soybean, and various strains/isolates have been reported to date. However, the pathogenic differences and phylogenetic relationships of these SMV strains/isolates have not been extensively studied. In the present work, by first obtaining 18 new genomic sequences of Chinese SMV strains/isolates and further compiling these with available data, we have explored the evolution of SMV from multiple aspects. First, as in other potyviruses, recombination has occurred frequently during SMV evolution, and a total of 32 independent events were detected. Second, using a maximum-likelihood method and removing recombinant fragments, a phylogeny covering 83 SMV sequences sampled from all over the world was reconstructed and the results showed four separate SMV clades, with clade I and II recovered for the first time. Third, the population structure analysis of SMV revealed significant genetic differentiations between China and two other countries (Korea and U.S.A.). Fourth, certain SMV-encoded genes, such as P1, HC-Pro and P3, exhibited higher non-synonymous substitution rate (dN) than synonymous substitution rate (dS), indicating that positive selection has influenced these genes. Finally, four Chinese SMV strains/isolates were selected for inoculation of both USA and Chinese differential soybean cultivars, and their pathogenic phenotypes were significantly different from that of the American strains. Overall, these findings have further broadened our understanding on SMV evolution, which would assist researchers to better deal with this harmful virus.

Widely known as a severe pathogen of bean plants, the bean common mosaic virus (BCMV) has been reported to infect soybeans only sporadically and the involved strains were all found in China regions. To explore variations among soybean-infecting BCMV strains, hundreds of soybean mosaic leave samples were collected throughout China, with a total of 30 BCMV isolates detected and their genomes sequenced. These newly obtained genomes, together with 16 other BCMV genomes available in GenBank were examined from multiple aspects to characterize BCMV evolutionary processes. Phylogenetic analysis showed that both soybean-infecting BCMVs (group I) and peanut-infecting BCMVs (group II) are distantly related to other BCMVs, suggesting ancestral differentiation and host adaptation. Genetic variation analysis showed that P1, P3 and 6K2 genes and the beginning portion of CP gene showed higher levels of variation relative to other genes. Moreover, selection analyses further confirmed that a number of sites within the P1 and P3 genes have suffered positive selection. These obtained BCMV sequences also exhibit high recombination frequencies, indicating a more dynamic evolutionary history. Finally, 12 different soybean cultivars were challenged with two BCMV isolates (DXH015 and HZZB011), with most of the cultivars successfully infected. These findings suggest that BCMV is indeed a potential threat to soybean production.

The present research project was undertaken to determine heavy metal (Pb, Co, Cd, Cr, Cu, Fe, Mn and Zn) concentrations in intensive aquaculture and wild white shrimp tissues (muscle, shell and liver), and to inform aquatic shrimp food safety. The aquaculture samples were obtained from ten intensive farms and wild animals from one station in Zhanjiang Harbour Bay. Heavy metal concentrations (mg kg−1, dry weight; means ± S.D.) in aquaculture white shrimp muscle, shell and liver tissues were, respectively: Cr – 20.86 ± 5.27, 28.70 ± 8.34 and 18.91 ± 5.50, Cu – 24.26 ± 8.36, 30.86 ± 9.84 and 126.42 ± 90.9, Fe – 61.35 ± 30.76, 55.07 ± 17.72 and 124.04 ± 56.15, Mn – 5.33 ± 2.5, 10.72 ± 4.34 and 8.79 ± 5.29, Zn – 171.56 ± 118.74, 51.84 ± 10.94 and 111.74 ± 84.67. Cadmium was observed only in liver tissue at 3.30 ± 1.29 mg kg−1. Lead could not be detected, and cobalt was detected only in wild shrimp liver tissue. Chromium and manganese mean concentrations in shell tissue were significantly higher than levels in muscle tissue (P