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New Guinea Impatiens (Impatiens hawkeri W. Bull) is an eye-popping landscaping plant which is of bright and colorful blooms. A highly efficient in vitro plant regeneration system through direct shoot organogenesis was established for the first time from hypocotyl with partial cotyledons of New Guinea Impatiens. The results showed that Explant sterilization method, basic medium type,AgNO3,sucrose and plant growth regulators (PGRs) have greatly influences on in vitro morphogenesis.The regeneration rate in regeneration media that MS supplemented with 0.5mg·L−1 TDZ and 0.1mg·L−1 NAA was acceptable ,the induction rate of 'Violet' was 86.67%, and its proliferation coefficient was 5.27, while the induction rate of 'Scarlet Bronze Leaf' was 83.33%, and its proliferation coefficient was 5.13.PIC was unable to induce clumped sprouts, but it had a better effect on callus induction.We also included a shoot multiplication stage using regeneration New Guinea Impatiens medium that MS supplemented with 0.8mg·L−1 6-BA,0.5mg·L−1 TDZ and 0.05mg ·L−1 NAA.Reducing sucrose concentration to 20g·L−1 or adding 1mg·L−1AgNO3 could alleviate the vitrification phenomenon in the process of tufted bud proliferation.The optimal root culture medium for the regenerated seedlings of 'violet' and 'scarlet bronze leaf' of New Guinea Impatiens was MS supplemented with 0.05mg·L−1IBA, the rooting rate reached 100%.The study examined the micropropagation responses of New Guinea Impatiens in the presence of various growth regulators and provided a simple and more suitable protocol adapted for the mass propagation of clones.

It is important to discover new pesticides with new modes of action because of the increasing evolution of pesticide resistance. In this study, a series of novel pyrimidin-4-amine derivatives containing a 5-(trifluoromethyl)-1,2,4-oxadiazole moiety were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR, and HRMS. Bioassays indicated that the 29 compounds synthesized possessed excellent insecticidal activity against Mythimna separata, Aphis medicagini, and Tetranychus cinnabarinus and fungicidal activity against Pseudoperonospora cubensis. Among these pyrimidin-4-amine compounds, 5-chloro-N-(2-fluoro-4-(5-(trifluoromethyl)-1,2,4-oxadiazol-3-yl)benzyl)-6-(1-fluoroethyl)pyrimidin-4-amine (U7) and 5-bromo-N-(2-fluoro-4-(5-(trifluoromethyl)-1,2,4-oxadiazol-3-yl)benzyl)-6-(1-fluoroethyl) pyrimidin-4-amine(U8) had broad-spectrum insecticidal and fungicidal activity. The LC50 values were 3.57 ± 0.42, 4.22 ± 0.47, and 3.14 ± 0.73 mg/L for U7, U8, and flufenerim against M. separata, respectively. The EC50 values were 24.94 ± 2.13, 30.79 ± 2.21, and 3.18 ± 0.21 mg/L for U7, U8, and azoxystrobin against P. cubensis, respectively. The AChE enzymatic activity testing revealed that the enzyme activities of compounds U7, U8, and flufenerim are 0.215, 0.184, and 0.184 U/mg prot, respectively. The molecular docking results of compounds U7, U8, and flufenerim with the AChE model demonstrated the opposite docking mode between compound U7 or U8 and positive control flufenerim in the active site of AChE. The structure-activity relationships are also discussed. This work provided excellent pesticide for further optimization. Density functional theory analysis can potentially be used to design more active compounds.

Electron transport across the transition-metal dichalcogenide (TMD)/metal interface plays an important role in determining the performance of TMD-based optoelectronic devices. However, the robustness of this process against structural heterogeneities remains unexplored, to the best of our knowledge. Here, we employ a combination of time-resolved photoemission electron microscopy (TR-PEEM) and atomic force microscopy to investigate the spatially resolved hot-electron-transfer dynamics at the monolayer (1L) MoS2/Au interface. A spatially heterogeneous distribution of 1L-MoS2/Au gap distances, along with the sub-80 nm spatial- and sub-60 fs temporal resolution of TR-PEEM, permits the simultaneous measurement of electron-transfer rates across a range of 1L-MoS2/Au distances. These decay exponentially as a function of distance, with an attenuation coefficient β ∼ 0.06 ± 0.01 Å-1, comparable to molecular wires. Ab initio simulations suggest that surface plasmon-like states mediate hot-electron-transfer, hence accounting for its weak distance dependence. The weak distance dependence of the interfacial hot-electron-transfer rate indicates that this process is insensitive to distance fluctuations at the TMD/metal interface, thus motivating further exploration of optoelectronic devices based on hot carriers. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Accepted version We acknowledge financial support from the A*STAR Advanced Optics in Engineering Program (122 360 0008) and the Ministry of Education (MOE2018-T2-1-081 and RG109/18), the National Natural Science Foundation of China (grant no. 21973006), the EU Graphene and Quantum Flagships, ERC grants Hetero2D, GSYNCOR, EPSRC grants EP/L0160871/1, EP/K01711X/1, and EP/K017144/1, and the U.S. National Science Foundation (grant no. CHE1900510).