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Direct analysis in real-time mass spectrometry (DART-MS) is an emerging in-situ ionization mass spectrometry analysis technology in recent years. DART is a non-contact surface desorption ionization technique, which is based on the principle of using helium or nitrogen as the working gas and generating excited high-energy particles by electric discharge. The excited state particles are accelerated by rapid heating and electric force, which instantly ionize the volatile compounds on the surface of the sample to be measured under atmospheric pressure, and then detected by mass spectrometry, thus achieving real-time direct analysis of the sample. DART-MS has the characteristics of simple sample preparation, quick and in-situ analysis. Since DART-MS was reported in 2005, it has become one of the most broadly used direct analysis methods and is extensively applied for the direct analysis of the quality, safety, origin and characteristics of food samples. Besides, it has been widely used in biomedicine, environmental monitoring, public safety, and drug analysis as well. Traditional Chinese medicines (TCMs) have been used for thousands of years in China, which gradually move towards to the world arena. The composition of TCM is very complicated, often containing many different chemical components of different types and properties, such as flavonoids, alkaloids, terpenoids, etc. Therefore, the analysis of the chemical basis of the efficacy and quality evaluation of TCMs are very crucial. In recent years, the development of DART-MS technology has provided many new opportunities for direct and rapid analysis of active ingredients in TCMs. The review was focused on the applications of DART-MS in TCMs, which covered the principle, characteristics, influencing factors and technological progress of DART-MS technology, and systematically summarized the research and application of this technology in TCMs, including qualitative and quantitative analysis. In addition, this review briefly introduced the progress of the application of DART-MS in combination with other techniques, such as thin-layer chromatography, imaging mass spectrometry and solid-phase microextraction in the profiling of TCMs, and provided further perspectives on its application development.

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We have studied the leptonic EDM and the LFV decays relating with the recent data of anomalous magnetic moment of muon, (g - 2) μ in the leptonic dipole operator. We have adopted the successful Γ 2 modular invariant model by Meloni–Parriciatu as the flavor symmetry of leptons. Suppose the anomaly of (g - 2) μ , Δ a μ to be evidence of New Physics (NP), we have related it with the anomalous magnetic moment of the electron Δ a e , the electron EDM d e and the μ → e γ decay. We found that the NP contributions to Δ a e (μ) are proportional to the lepton masses squared likewise the naive scaling Δ a ℓ ∝ m ℓ 2 . The experimental constraint of | d e | is much tight compared with the one from the branching ratio B (μ → e γ) in our framework. Supposing the phase of our model parameter δ α for the electron to be of order one, we have estimated the upper-bound of B (μ → e γ) , which is at most 10 - 21 - 10 - 20 . If some model parameters are real, leptonic EDMs vanish since the CP phase of the modular form due to modulus τ does not contribute to the EDM. However, we can obtain B (μ → e γ) ≃ 10 - 13 with non-vanishing d e in a specific case. The imaginary part of a parameter can lead to d e in the next-to-leading contribution. The predicted electron EDM is below 10 - 32 e cm, while B (μ → e γ) is close to the experimental upper-bound. The branching ratios of τ → e γ and τ → μ γ are also discussed. [ABSTRACT FROM AUTHOR]

Ectropis grisescens Warren is one of the most important pests of tea plants. In this study, data on the development, survival, and fecundity of E. grisescens were collected at 15, 22, and 32 °C and analyzed by using the age-stage, two-sex life table. At 15 °C, the duration of the preadult period of E. grisescens was significantly prolonged (81.06 days), with high mortality (69.0%), and the proportion of emerged female adults was extremely low (7.0%). At 32 °C, the preadult period was significantly shortened (29.12 days), with high preadult mortality (74.0%), and a low proportion of emerged female adults (15.0%). At 22 °C, with low preadult mortality (24.0%), and a high proportion of emerged female adults (26.0%). The overall effects of the shorter preadult duration, higher preadult survival rate, higher proportion of emerged female adults, higher fecundity (F = 350.88 eggs/♀), and higher net reproductive rate (R0 = 91.23 offspring/individual) at 22 °C resulted in the highest values of the intrinsic rate of increase (r = 0.1054 days–1) and finite rate of increase (λ = 1.1112 days–1). Computer simulation showed that E. grisescens populations can increase much faster at 22 °C than at 15 and 32 °C. The weighted population size and cumulative weighted insect-days provided the dynamics necessary for estimating the damage potential of E. grisescens in devising economical pest management programs. Our results demonstrate that populations of E. grisescens were able to develop at a broad range of temperatures and adapt to the high temperatures. These finding can be utilized to improve the management of E. grisescens. Graphical Abstract Age-stage, two-sex life table can reveal the survival and stage differentiation for assessment of differences between temperatures. [ABSTRACT FROM AUTHOR]

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives from α-CF3 alkenes with formate as the carbonyl source was disclosed. The reaction can undergo selective mono- or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer (HAT) catalyst under visible-light-induced conditions at room temperature. Foramte acts as both the C1 source and the reductant through the generation of CO2•− species, which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process. [ABSTRACT FROM AUTHOR]