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This article is an historical study of the understanding of children's writing through "Language Arts". The author and her research team did a content analysis of articles about writing that appeared in "Language Arts" beginning in 1924 through January, 2010. Analysis shows that a major area of tension throughout the history of the journal has been between conceptualizations of writing as a form of language use for children's thinking and expression and writing as a standardized set of skills and processes. The authors propose that these positions can be traced, through the pages of "Language Arts", to contrasting perspectives on the value of diversity in experience, interest, and language use, and on standardization versus teacher control of curriculum. (Contains 3 footnotes.)

Wuyi rock tea (WRT) is one of the most famous subcategories of oolong tea, exhibiting distinct aroma characteristics with the application of different cultivars. However, a comprehensive comparison of the characteristic volatiles among WRTs with different cultivars has rarely been carried out. In this study, non-targeted analyses of volatile fragrant compounds (VFCs) and targeted aroma-active compounds in WRTs from four different cultivars were performed using chemometrics and gas chromatography olfactometry/mass spectrometry (GC-O/MS). A total of 166, 169, 166, and 169 VFCs were identified for Dahongpao (DHP), Rougui (RG), Shuixian (SX), and Jinfo (JF), respectively; and 40 components were considered as the key differential VFCs among WRTs by multivariate statistical analysis. Furthermore, 56 aroma-active compounds were recognized with predominant performances in "floral & fruity", "green & fresh", "roasted and caramel", "sweet", and "herbal" attributes. The comprehensive analysis of the chemometrics and GC-O/MS results indicated that methyl salicylate, p-cymene, 2,5-dimethylpyrazine, and 1-furfurylpyrrole in DHP; phenylethyl alcohol, phenethyl acetate, indole, and (E)-β-famesene in RG; linalool, phenethyl butyrate, hexyl hexanoate, and dihydroactinidiolide in JF; and naphthalene in SX were the characteristic volatiles for each type of WRT. The obtained results provide a fundamental basis for distinguishing tea cultivars, recombination, and simulation of the WRT aroma. [ABSTRACT FROM AUTHOR]

• A novel approach was established to analyze 23 chiral volatile components in tea. • The racemic form of dihydroactinidiolide was observed in all stored white teas. • Both enantiomeric ratio and content of S-linalool decreased in stored white teas. • The contents of S/R-dihydroactinidiolide obviously increased in stored white teas. Precise identification of the compounds characteristic to stored white teas is urgently needed as these products have unique flavors and health benefits that improve with storage duration. Owing to the potential applications in food quality discrimination, specific regularities between the enantiomeric distributions of 23 volatile lactones and terpenoids and storage durations of white teas were expected and investigated by enantioselective gas chromatography-mass spectrometry (Es-GC-MS) combined with multivariate statistical analysis. High correlation coefficients (−0.853 to 0.695) and significant differences (P < 0.001) between the enantiomeric ratios (ERs) of (2S, 5S)-linalool oxide A, (2S, 5R)-linalool oxide B, (2R, 5S)-theaspirane B, S-linalool, and (1R, 2S)-methyl epijasmonate and the storage durations (0–7 years) were obtained, and the contents of S-linalool and S/R-dihydroactinidiolide significantly decreased and increased, respectively, with the increasing of storage duration. Therefore, the aforementioned lactone and terpenoid enantiomers are potential markers for the reliable differentiation of white teas stored for different time periods. [ABSTRACT FROM AUTHOR]