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1.
Front Psychol ; 13: 738982, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386905

RESUMO

This study investigated the internal mechanism of the relationship between primary school students' peer relationships and their performance in the Chinese language and literature. We constructed a chain mediation model, focused on the mediation effects of parental involvement and the sense of autonomy, on the correlation between peer relationships and performance in Chinese language scores. A questionnaire survey was conducted among 1,503 students in grades 4-6, and their parents, in three cities in Jiangsu Province. The result indicated the following: (1) there was a significant positive correlation between primary school students' peer relationships, parental involvement, sense of autonomy, and the level of Chinese language scores; (2) parental involvement and the sense of autonomy, respectively, mediate the relationship between peer relationships and Chinese language scores; (3) primary school students' parental involvement and sense of autonomy play a chain-like mediating role in the relationship between their peer relationships and Chinese language scores. The research results provide a reference for exploring the educational strategies of primary school students' Chinese literacy.

2.
J Food Sci ; 79(11): M2308-14, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25296711

RESUMO

Methanol, often generated in brewed wine, is highly toxic for human health. To decrease the methanol content of the brewed wine, atmospheric and room-temperature plasma (ARTP) was used as a new mutagenesis tool to generate a mutant of Saccharomyces cerevisiae with lower methanol content. Headspace gas chromatography was used to determine the identity and concentration of methanol with butyl acetate as internal standard in brewed wine. With 47.4% higher and 26.3% positive mutation rates were obtained, the ARTP jet exhibited a strong effect on mutation breeding of S. cerevisiae. The mutant S. cerevisiae S12 exhibited the lowest methanol content, which was decreased by 72.54% compared with that of the wild-type strain. Subsequently, the mutant S. cerevisiae S12 was used to ferment different combinations of malt and adjuncts for lower methanol content and higher alcoholic content. It was shown that the culture 6#, which was 60% malt, 20% wheat, and 20% corn, was the best combinations of malt and adjuncts, with the lowest methanol content (104.8 mg/L), and a relatively higher alcoholic content (15.3%, v/v). The optimal malt-adjunct culture 6#, treated with the glucoamylase dose of 0.04 U/mg of grain released the highest reducing sugars (201.6 mg/mL). It was indicated that the variation in reducing sugars among the combinations of malt and different adjuncts could be due to the dose of exogenous enzymes.


Assuntos
Fermentação , Metanol/análise , Temperatura , Vinho/análise , Cromatografia Gasosa , Meios de Cultura/química , Mutagênese , Mutação , Gases em Plasma/química , Saccharomyces cerevisiae/metabolismo , Triticum/química , Zea mays/química
3.
Zhongguo Zhong Yao Za Zhi ; 39(11): 2029-33, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25272836

RESUMO

Ten compounds were isolated from the barks of Jasminum giraldii by means of various of chromatographic techniques such as silica gel, Sephadex LH-20 and Rp-HPLC. Their structures were identified by spectroscopic data analysis as (+)-medioresinol (1), (+) -syringaresinol (2), syringaresinol-4'-O-beta-D-glucopyranoside (3), oleanic acid (4), 3-methoxy-4-hydroxy-trans-cinnamaldehyde (5), trans-sinapaldehyde (6), syringaldehyde (7), 1-(4-methoxy -phenyl) -ethanol (8), trans-cinnamic acid (9), and 4-(1-methoxyethyl) -phenol (10). Among them, compounds 1-3, 5-8 and 10 were isolated from the J. genus for the first time and compounds 4 and 9 were obtained from J. giraldii for the first time. In the DPPH free radical scavenging assay, compound 1 exhibited significant activity (IC50 55.1 micromol x L(-1)), compared with vitamin C(IC50 59.9 micromol x L(-1)); and compound 2 showed moderate activity (IC50 79.0 micromol x L(-1)), compared with 2, 6-di-tert-butyl4-methylphenol (IC50 236 micromol x L(-1)).


Assuntos
Antioxidantes/química , Medicamentos de Ervas Chinesas/química , Jasminum/química , Antioxidantes/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
4.
Zhongguo Zhong Yao Za Zhi ; 39(9): 1635-8, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095375

RESUMO

Seven compounds were isolated from the leaves of Panax japonicus var. major by chromatographic methods including silica gel, Sephadex LH-20, ODS and semi-preparative HPLC. Their structures were elucidated by their physical and chemical properties and spectral data analysis as 5, 7-dihydroxy-8-methoxyl flavone (1), ginsenoside Rs2 (2), quinquenoside R1 (3), ginsenoside Rs1 (4), notoginsenoside Fe (5), ginsenoside Rd2 (6) and gypenosiden IX (7). Among them, compound 1 was obtained from the Panax genus for the first time, and compounds 2-7 were isolated from this plant for the first time.


Assuntos
Flavonas/análise , Ginsenosídeos/análise , Panax/química , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão , Flavonas/química , Flavonas/isolamento & purificação , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
5.
Zhongguo Zhong Yao Za Zhi ; 39(8): 1445-9, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25039180

RESUMO

Ten compounds were isolated from the leaf of Eucommia ulmoides by means of recrystallization and chromatographic techniques such as D-101 macroporous resin, MCI resin, ODS gel, Sephadex LH-20 and Rp-HPLC. Their structures were identified by NMR spectral analyses as kaempferide 3-O-beta-D-glucoside (1), quercetin-3-O-beta-D-glucoside (2), quercetin (3), quercetin-3-O-beta-D-xylosyl-(1-->2)-beta-D-galactoside (4), kaempferol-3-O-alpha-L-rhamnosyl-(1-->6)-beta-D-glucoside (5), (2S,3S)-taxifolin 3-O-beta-D-glucoside (6) ,4-hydroxy cinnamic acid (7), (+)-cycloolivil (8), pinoresinol beta-D-glucoside (9), squalene (10). Among them compounds 1,5-7,10 were isolated from the Eucommia genus for the first time. In the DPPH free radical scavenging assay, compound 2 exhibited significant activity (IC50 13.7 micromol x L(-1)), compared with vitamin C (IC50 59.9 micromol x L(-1)); compounds 1, 3 and 9 showed moderate activity (IC50 161,137, 214 micromol x L(-1)), compared with 2,6-di-tert-butyl-4-methylphenol (IC50 236 micromol x L(-1)); compound 4 and 6 showed weak activity (IC50 264, 299 micromol x L(-1)).


Assuntos
Medicamentos de Ervas Chinesas/química , Eucommiaceae/química , Folhas de Planta/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Estrutura Molecular
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