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• Dark induces decrease of chlorophylls and leaf yellowing in cut chrysanthemum flowers. • Chlorophyll degradation in dark is not associated with ethylene production. • Dark may accelerate leaf yellowing markedly compared to ethylene application. Chrysanthemums (Chrysanthemum × morifolium) are the most widely produced cut flowers in Japan. During transportation, the leaves of cut small-flowered chrysanthemums grown in the summer season sometimes turn yellow. The previous study used detached chrysanthemum leaves to clarify the acceleration of leaf yellowing due to warm temperatures and dark conditions. In this study, to clarify the relationship between ethylene and leaf-yellowing senescence induced in cut small-flowered 'Kosuzu' chrysanthemums, ethylene production and sensitivity to ethylene were investigated. Under 24 h of continuous darkness (DD conditions), leaves turned yellow during the experimental period (days 0 to 9), with lightness (L*) and chroma (C*) values of leaves increasing from 35.8 to 53.6 and from 19.1 to 42.8, respectively, and hue values decreasing from 128.0 to 112.9. The concentrations of chlorophyll a and b decreased more under DD conditions than under storage under 12 h light/12 h dark (LD) conditions. Ethylene production by leaves decreased under both light regimes. At days 3 and 4, the leaves of LD flowers produced more ethylene than those of DD flowers. Under both light regimes, treatment with ethylene (10 µL/L for 24 h) did not accelerate leaf-yellowing compared to the control (no ethylene treatment). Hue values of leaves decreased immediately in DD flowers, regardless of ethylene treatment, but there was almost no change in LD flowers during the experimental period. The results suggest that dark conditions induce chlorophyll degradation and leaf-yellowing senescence, chlorophyll degradation under dark conditions is not associated with an increase in endogenous ethylene, and dark conditions may accelerate leaf yellowing markedly compared to exogenous ethylene application in cut small-flowered chrysanthemums. [ABSTRACT FROM AUTHOR]

Background: It is commonly believed that there is serious heterogeneity in the rate of wrinkle progression among individuals. Although several skin characteristics have been shown to influence wrinkle progression, the ability to predict which individuals with skin characteristics are likely to develop wrinkles is still limited., Objectives: The purpose of this study is to develop and validate an effective prediction model for longitudinal changes in wrinkles., Methods: We collected annual wrinkle scores and multiple skin physiological characteristics in 48 Japanese women over a period of 7 years. We developed a multivariable prediction model for predicting future wrinkle status based on the various skin physiological characteristics using a linear mixed-effects model., Results: After variable selection by backwards, the final wrinkle prediction model included age, sebum volume, redness of skin color, lightness of skin color, and an interaction term between sebum volume and redness of skin color. The developed prediction model showed favorable prediction accuracy (R 2  = 87.92%, 95% confidence interval 84.27%-90.68%)., Conclusions: The developed model accurately predicted levels of wrinkles in Japanese women aged 22-60 years. The prediction model is based on age and three practical skin characteristics, which might implicate an essential insight to prevent wrinkle progression in individuals., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)