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The pupose of this review was to explore the application of machine learning in the realm of flavor molecule research, particularly in the analysis of the flavor of Jasmine tea. The study of flavor molecules is fundamental to understand and optimize the taste and quality of food, especially tea. The introduction of machine learning technology has opened new horizons for the identification and analysis of flavor molecules. This paper firstly outlined the basic concepts and research methods of flavor molecules, and a detailed discussion on the application of machine learning in deciphering the relationships between molecular structures and flavor characteristics, as well as in the analysis, prediction and optimization of the flavor and intelligent processing of Jasmine tea and other applications, put forward the research prospect. Thereby, this review could enhance the quality of Jasmine tea and provide technical support for the further development of the tea industry.

In this article, Fe–8.5Mn–1.5Al medium‐manganese steel is taken as the research object, and Gleeble 3500 thermal simulation testing machine is used to conduct isothermal compression at different deformation temperatures, strain rates, and strains in its austenite ferrite two‐phase zone. A constitutive model and a dynamic recrystallization volume fraction model for materials are established, and finite‐element method is used to simulate the temperature, equivalent strain, and dynamic recrystallization volume fraction distribution in different regions of the workpiece under different deformation conditions. By comparing and analyzing the microstructure, finite‐element simulation results, and hot working diagrams obtained from the experiment, the microscopic mechanism of dynamic softening of the material when ferrite and austenite coexist is explained; the transformation of the dynamic softening mechanism of the two phases with the hot deformation process is also explained. Early deformation mainly occurs in softer ferrite, which preferentially undergoes continuous dynamic recrystallization. Austenite has a lower stacking fault energy, and discontinuous dynamic recrystallization (DDRX) occurs when the dislocation density reaches a certain critical value. At the same time, when the strain reaches a certain level, the dynamic softening behavior of ferrite will also transform into DDRX. The optimal deformation conditions for Fe–8.5Mn–1.5Al medium‐manganese steel during warm processing in the two‐phase zone are a temperature of 720 °C, a strain rate of 0.01 s−1, and a large deformation zone. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)‐catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all‐carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram‐scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven‐membered nitrogen heterocycles. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)‐catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all‐carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram‐scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven‐membered nitrogen heterocycles. [ABSTRACT FROM AUTHOR]

Enantioselective synthesis of (spiro)cyclobutane derivatives poses significant challenges yet holds promising applications for both synthetic and medicinal chemistry. We report here a nickel-catalyzed asymmetric syn-hydrometalative 4-exo-trig cyclization of alkynones to synthesize alkenyl cyclobutanols with a tetrasubstituted stereocenter. This strategy features a broad substrate scope, delivering a variety of trifluoromethyl-containing rigid (spiro)carbocycle skeletons in good yields and high enantioselectivities (up to 84% yield and 98.5:1.5 er). The synthetic utility is demonstrated through stereospecific transformations into fused spirocycles. Experimental and computational mechanistic studies indicate that the reaction is initiated by an active Ni-H species, with carbonyl-directed hydrometalation as the key for regioselective control. This catalytic method provides a general solution for regioselective hydrofunctionalization of alkynes and represents an efficient reaction pattern for assembling highly strained enantioenriched bioisosteres., (© 2024 Wiley‐VCH GmbH.)

Acupuncture is an effective measure for treating type 2 diabetes mellitus (T2DM). Many studies have shown that acupuncture can reduce blood glucose in patients with T2DM, but its mechanism is still unclear. This review summarized the mechanism of acupuncture on T2DM, the mechanisms of acupuncture in treating T2DM is related to improving insulin resistance, regulating inflammation, promoting insulin secretion, improving lipid metabolism disorders, resisting oxidative stress, improving obesity, controlling intestinal flora, and regulating the nervous system. At the same time, this review also points out the lack of current relevant research and the future research directions to provide a reference for further exploring the mechanism of acupuncture hypoglycemic action.

Objective: To explore the mechanisms of Qianlie Jindan Tablets (QLJD) acting on chronic nonbacterial prostatitis (CNP) in rats based on non-targeted urine metabolomics., Methods: According to the body mass index, we equally randomized 30 eight-week-old male SD rats into a blank control, a CNP model control and a QLJD medication group. We established the CNP model in the latter groups and, from the 4th day of modeling, treated the rats in the blank and model control groups intragastrically with normal saline and those in the QLJD medication group with QLJD suspension, qd, for 30 successive days. Then we detected the changes in the metabolites of the rats by ultra-high-performance liquid chromatography-tandem mass spectrometry, and identified the differential metabolites in different groups by multivariate statistical analysis, followed by functional annotation of the differential metabolites., Results: Eight common metabolites were identified by metabolomics analysis, of which 5 were decreased in the CNP model controls and increased in the QLJD medication group, while the other 3 increased in the former and decreased in the latter group. Creatinine and genistein were important differential metabolites, and the arginine and proline metabolic pathways and isoflavone biosynthesis pathways were the main ones for QLJD acting on CNP. Compared with the blank controls, the model controls showed up-regulated arginine and proline metabolic pathways, increased production of creatinine, down-regulated isoflavone biosynthetic pathway and decreased production of genistein. The above changes in the model controls were all reversed in the QLJD medication group., Conclusion: QLJD acts effectively on CNP in male rats by regulating L-arginine and proline metabolic pathways, as well as the isoflavone biosynthesis pathway and naringenin metabolism.

Microplastic pollution in the soil environment has received extensive attention, but the effects of different land use patterns on the sub-watershed scale on soil microplastic pollution are poorly understood. The Luoshijiang sub-watershed in the north of Erhai Lake was selected as the research object, and the characteristics of microplastic pollution in farmland, riparian zone, grassland, and woodland soils were analyzed. The pollution risks of microplastics in the four types of soil were assessed using the polymer risk index method, and the effects of land use patterns on the distribution and risk of microplastic pollution were further explored. The results showed that:① The abundance of microplastics in the soil of the Luoshijiang sub-watershed ranged from 220 to 1 900 n·kg -1 , and the average abundance was (711 ± 55) n·kg -1 . The main polymer types were polyester (PES, 32.52%) and polyethylene terephthalate (PET, 21.95%). The particle size of microplastics was concentrated in the range of 0.5-2 mm (61.89%). Fiber was the main shape of microplastics (>75%), and the dominant color was transparent (58.50%). ② Land use patterns determined the abundance and pollution characteristics of soil microplastics in the Luoshijiang sub-watershed. A significantly higher abundance of microplastics was found in the soil of farmland[(885 ± 95) n·kg -1 ] and riparian zone[(837 ± 155) n·kg -1 ], which had stronger intensities of human activity, than that in woodland soil[(491 ± 53) n·kg -1 ] ( P <0.05). Film and fragment microplastics mainly occurred in farmland soil, which also had the largest number of polymer types and the most abundant colors. ③ The risk index level of microplastics (Level Ⅲ) in the soil of farmland was higher than that of the other three land use patterns (Level Ⅰ). This research indicated that the higher the intensity of human activities of a sub-watershed was, the more complex the occurrence characteristics of soil microplastics, the richer the types of polymers, and the higher the potential pollution risks would be. Therefore, it is necessary to strengthen the control of soil microplastic pollution in farmland.