摘要： By re-analzying public metagenomic data from 101 patients infected with influenza A virus during the 2007-2012 H1N1 flu seasons in France, we identified 22 samples with SARS-CoV sequences. In 3 of them, the SARS genome sequences could be fully assembled out of each. These sequences are highly similar (99.99% and 99.7%) to the artificially constructed recombinant 5 SARS-CoV (SARSr-CoV) strains generated by the J. Craig Venter Institute in USA. Moreover, samples from different flu seasons have different SARS-CoV strains, and the divergence between these strains cannot be explained by natural evolution. Our study also shows that retrospective studies using public metagenomic data from past major epidemic outbreaks serves as a genomic strategy for the research of origins or spread of infectious diseases.
摘要： 新冠病毒的起源仍不清楚。了解新冠病毒如何、何时以及在何处从其天然宿主传播给人类对于预防未来由冠状病毒引发的疫情至关重要。 从与病原体无休止的战斗中吸取教训，结合目前已知的关于新冠病毒起源和中间宿主的研究数据，我们提出全球多个地点都有可能是新冠病毒的起源地。
摘要： In the comparison with SARS-CoV of 2003, SARS-CoV-2 is extremely well adapted to the human populations and its adaptive shift from the animal host to humans must have been even more extensive. By the blind watchmaker argument, such an adaptive shift can only happen prior to the onset of the current pandemic and with the aid of step-by-step selection. In this view, SARS-CoV-2 could not have possibly evolved in an animal market in a big city and even less likely in a laboratory. Discussions of the origin of SARS-CoV-2 need to factor in the long process of adaptive shift and some models have indeed advanced in that direction.
摘要：We study the dipion transitions (4S) → (nS)π+π− (n = 1, 2). In particular, we consider the effects of the two intermediate bottomoniumlike exotic states Zb(10610) and Zb(10650) as well as bottom meson loops. The strong pion–pion final-state interactions, especially including channel coupling to K ¯K in the S-wave, are taken into account modelindependently by using dispersion theory. Based on a nonrelativistic effective field theory we find that the contribution from the bottom meson loops is comparable to those from the chiral contact terms and the Zb-exchange terms. For the (4S) → (2S)π+π− decay, the result shows that including the effects of the Zb-exchange and the bottom meson loops can naturally reproduce the two-hump behavior of the ππ mass spectra. Future angular distribution data are decisive for the identification of different production mechanisms. For the (4S) → (1S)π+π− decay, we show that there is a narrow dip around 1GeV in the ππ invariant mass distribution, caused by the final-state interactions. The distribution is clearly different from that in similar transitions from lower states, and needs to be verified by future data with high statistics. Also we predict the decay width and the dikaon mass distribution of the (4S) → (1S)K+K− process.
摘要：Within the framework of dispersion theory, we analyze the dipion transitions between the lightest Υ states, Υ(nS)→Υ(mS)ππ with m