About one percent of giants[1] are detected to have anomalously high lithium (Li) abundances in their atmospheres, conflicting directly with the prediction of the standard stellar evolution models [2] , and making the production and evolution of Li more intriguing, not only in the sense of the Big Bang nucleosynthesis [3,4] or the Galactic medium [5] , but also the evolution of stars. [6,7,8] , yet the origins of Li-rich giants are still being debated. Here we report the discovery of the most Li-rich giant known to date, with a super-high Li abundance of 4.51. This rare phenomenon was snapshotted together with another short-term event that the star is experiencing its luminosity bump on the red giant branch. Such high Li abundance indicates that the star might be at the very beginning of its Li-rich phase, which provides a great opportunity to investigate the origin and evolution of Li in the Galaxy. A detailed nuclear simulation is presented with up-to-date reaction rates to recreate the Li enriching process in this star. Our results provide tight constraints on both observational and theoretical points of view, suggesting that low-mass giants can produce Li inside themselves to a super high level via 7 Be transportation during the red giant phase. Decades of efforts have been put into explaining why such outliers existLithium is too fragile to survive in deeper layers of a stellar atmosphere due to the high temperature. Thus the first dredge up (FDU) process can sharply dilute the surface Li abundance in red giants. That explains why the first discovery [9] of a Li-rich giant evoked great interests on exploring and understanding the Li-rich objects. However, only about 150 Li-rich giants have been found [1,10,11,12,13,14] in the past three decades, and ∼ 20 of them were found to be super Li-rich with Li abundances higher than 3.3. Considering the NLTE corrections, three [12,15,16] stars were found to be at a level of A(Li) > 4.0. Such rare objects could provide a great opportunity to reveal the nature of the phenomenon of Li-richness because high Li abundance cannot be maintained for a long time due to frequent convection activity. Taking advantage of the powerful ability for spectral collection with the Large Sky Area Multi-Object * sjr@nao.cas.cn † gzhao@nao.cas.cn 1 Fiber Spectroscopy Telescope (LAMOST), we have obtained a large sample of Li-rich candidates by measuring the equivalent width of the Li I line at λ = 6707.8 Å. One of our candidates, TYC 429-2097-1, has a super strong Li absorption line (see Fig. 1, panel a). We then made a follow-up high-resolution observation with the 2.4-m Automated Planet Finder Telescope (APF) located at Lick Observatory on June 23, 2015. The spectrum covers a wavelength range of 374 nm − 970 nm with a resolution of ∼ 80, 000. The total integration time was 1.5 hours and was divided into three single exposures (30 minutes each) for a better subtraction of cosmic-rays. The spectrum of TYC 429-2097-1 obtained from APF is presented in Fig. 1, panels (b) and (e), where the spec...

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The meadow moth, Loxostege sticticalis, is a typical agricultural pest that uses sex pheromones to mediate mating behavior; however, the mechanism underlying the selectivity of its pheromone-binding proteins (PBPs) remains unknown. In this study, LstiPBP1 and LstiPBP3 were cloned, expressed, and purified, and the fluorescence binding assay showed that LstiPBP1 binds to the major sex pheromone component, E-11-tetradecenol (E11-14:OH), with high affinity; moreover, E11-14:OH could evoke a significant antennal electrophysiological response and attract L. sticticalis males. After LstiPBP1 was silenced, both the antennal response and attractiveness of E11-14:OH decreased significantly. Molecular docking predicted that a hydrogen bonding site, Leu37, played key role in the binding of LstiPBP1 to E11-14:OH. After Leu37 was mutated, the E11-14:OH-binding affinity decreased drastically. These results suggest that LstiPBP1 participates in E11-14:OH recognition and could be used as a target gene to disturb the mating behavior of L. sticticalis and develop new odorants for pest control.

The radiative capture reaction plays an important role in nuclear astrophysics. We have indirectly measured the astrophysical S(E) factors for some proton capture reactions and reaction rates for several neutron capture reactions with one nucleon transfer reactions at HI-13 tandem accelerator in recent years. Some of them are compiled into IAEA EXFOR database and JINA REACLIB project, and used in the network calculations of Big Bang nucleosynthesis and type-I X-ray bursts.