Ten coumarins were isolated from the root of Angelica dahurica by repeated silica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, oxypeucedanin hydrate acetonide (7) was isolated for the first time from this plant. Cytotoxicity of coumarins isolated were determined in vitro against L1210, HL-60, K562, and B16F10 tumor cell lines by MTT method. Pangelin (5) and oxypeucedanin hydrate acetonide (7) showed a potent cytotoxic activity with the IC50 values of 8.6 to 14.6 microg/mL against four kinds of tumor cell lines. Other compounds showed the moderate cytotoxic activity or no activity against the tumor cell lines.

Background: There are limited psychometric reports of construct validity following adaptation of the Bayley Scales of Infant and Toddler Development 3rd edition (Bayley III). This paper aims to demonstrate a process of assessing reliability, validity, and gender equivalence of the adapted tool for Vietnamese children. Methods: We evaluated cognitive, fine motor, gross motor, expressive communication and receptive communication subtests of the adapted tool in 267 healthy urban Vietnamese children. Subsets of participants were used to evaluate inter-observer and test-retest reliability. Confirmatory factor analysis (CFA) was carried out to evaluate construct validity and measurement invariance between genders. Results: The adaptation demonstrated good inter-observer and test-retest reliability. CFA indicated that a construct representing a single underlying factor showed the best fit, although relationships between the observed scores and the latent traits underlying the scores varied between age groups. Within age groups, relationships between observed scores and these factors were not significantly influenced by gender. Conclusions: The Vietnamese Bayley III demonstrated good internal consistency and reliability. A latent structure with one general factor and additional residual correlations that change with age is supported by the theoretical understanding of child development. This is the first study to demonstrate gender invariance by age group. This adaptation is suitable for further research studies in urban Vietnamese children, but further work is needed to extend its applicability more broadly across Vietnam.

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Vibro-acoustic analysis of a finite orthotropic laminated double-composite plate with enclosed air cavity on an infinite acoustic rigid baffle is investigated analytically. Using the acoustic velocity potential to describe the acoustic vibration performance of a simple supported structure, the sound transmission loss (STL) is calculated from the ratio of incident to transmitted acoustic powers. Specifically, the focus is placed on the effects of several key system parameters on sound transmission including the plate dimensions, the laminate configurations, the boundary conditions and the composite materials are systematically examined.