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Objectives: Previous research suggests potential moderating roles of dispositional mindfulness and body image flexibility in the association between body dissatisfaction and disordered eating. However, relevant research is mainly conducted on adult women from Western countries, and limited evidence exists for adolescent samples, especially from non‐Western contexts (e.g., China). Thus, this study aimed to examine the moderating roles of dispositional mindfulness and body image flexibility in the relationship between body dissatisfaction and disordered eating in Chinese adolescents. Method: We recruited 545 Chinese adolescents (53.9% boys, aged 12–16 years) who completed measures of body dissatisfaction, dispositional mindfulness, body image flexibility, and disordered eating. Moderation analyses were examined with PROCESS macro on SPSS. Results: In separate models, both higher dispositional mindfulness and body image flexibility weakened relationships between body dissatisfaction and disordered eating. However, when both dispositional mindfulness and body image flexibility were entered into the same moderation model, only body image flexibility showed a significant moderating effect. Discussion: Both dispositional mindfulness and body image flexibility may weaken the association between body dissatisfaction and disordered eating in adolescents. However, body image flexibility might have a stronger effect than dispositional mindfulness. These findings suggest that interventions aimed at reducing body dissatisfaction to prevent disordered eating in adolescents may pay more attention to adolescents' body image flexibility. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a new method to prove the blowup at $ +\infty $ for the solution of the initial boundary value problem for a class of semilinear parabolic equations with logarithmic nonlinearity at sub-critical initial energy level by contradiction. Moreover, following the idea of contradiction, we obtained a sufficient criterion for the blowup at $ +\infty $ of the solution with arbitrarily positive initial energy by defining a new auxiliary function, in which the location of the initial data concerning the unstable set is not required. [ABSTRACT FROM AUTHOR]

Wood can store carbon and help mitigate global climate change. Carbon density (CD), the basis for measuring and analyzing C storage, is the product of wood density (WD) and C concentration, which are dependent on wood structure, cellulose concentration (CC), hemicellulose concentration (HC), and lignin concentration (LC). However, little attention has been paid to the C concentration of cellulose, hemicellulose, and lignin, which are fundamental factors in C storage and affect the credibility of accurate CD estimates. In order to disentangle the CD drives, WD, C concentration, CC, HC, and LC of the branch, stem, and root were quantified for five Rosaceae species from temperate forests in Northeastern China. The species were Sorbus alnifolia (Sieb.et Zucc.) K. Koch, Pyrus ussuriensis Maxim., Malus baccata (L.) Borkh., Crataegus pinnatifida var. major N. E. Brown, and Padus racemosa (Linn.) Gilib. The WD, CC, HC, and LC differed among species and tree organs, with the highest variability for the HC. The structural carbon concentration (SCC) was lower than the organic carbon concentration (OCC) and even the Intergovernmental Panel on Climate Change (IPCC) default value of 45%, with a maximum deviation of 2.6%. CD differed dramatically among species and tree organs. Based on SCC calculations, the highest CD was found in Sorbus alnifolia root (0.27 × 106 g/m3), while the lowest was found in Padus racemosa branch (0.22 × 106 g/m3). The results suggest that when estimating CD accurately at species level, it is important to consider not only WD but also structural carbohydrates and lignin concentration, providing important information on C fluxes and long-term C sequestration for forests. The study findings provide valuable insights into CD variations among tree species and organs and are valuable for forest management and policy development to improve carbon sequestration. [ABSTRACT FROM AUTHOR]

Leaf nutrient resorption is a critical process in plant nutrient conservation during leaf senescence. However, the ecological mechanisms underlying the large variability in nitrogen (NRE) and phosphorous (PRE) resorption efficiencies among trees remain poorly understood. We conducted a comprehensive study on NRE and PRE variability using 61 tree individuals of 10 temperate broad-leaved tree species. Three potentially interrelated intrinsic ecological mechanisms (i.e., leaf senescence phenology, leaf pigments, and energy residual) were verified. We found that a delayed leaf senescence date, increased degradation of chlorophylls and carotenoids, biosynthesis of anthocyanins, and reduced nonstructural carbohydrates were all positively correlated with NRE and PRE at the individual tree level. The intrinsic factors affecting resorption efficiency were ranked in decreasing order of importance: leaf pigments > energy residual > senescence phenology. These factors explained more variability in NRE than in PRE. Our findings highlight the significance of these three ecological mechanisms in leaf nutrient resorption and have important implications for understanding how nutrient resorption responds to climate change. [ABSTRACT FROM AUTHOR]

In this paper, the initial boundary value problem for a nonlocal semilinear pseudo-parabolic equation is investigated, which was introduced to model phenomena in population dynamics and biological sciences where the total mass of a chemical or an organism is conserved. The existence, uniqueness and asymptotic behavior of the global solution and the blowup phenomena of solution with subcritical initial energy are established. Then these results are extended parallelly to the critical initial energy. Further the blowup phenomena of solution with supercritical initial energy is proved, but the existence, uniqueness and asymptotic behavior of the global solution with supercritical initial energy are still open.

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This paper deals with the initial boundary value problem of a class of fourth order wave equations with nonlinear strain and linear weak damping terms. By establishing the invariance of the unstable set and a delicate auxiliary function, we give a sufficient condition such that the solution blows up in a finite time at high initial energy level. [ABSTRACT FROM AUTHOR]

Optical methods have been widely used to estimate seasonal changes of the leaf area index (LAI) in forest stands because they are convenient and effective; however, their accuracy in deciduous broadleaf forests has rarely been evaluated. We estimate the seasonal changes in the LAI by combining periodic observations of leaf area variation with litter collection ([LAI.sub.dir]) in deciduous broadleaf forests and use these estimates to evaluate the accuracy of optical LAI measurements made using digital hemispherical photography (DHP). We also propose a method to correct DHP-derived LAI ([LAI.sub.DHP]) values for seasonal changes in major factors that influence the determination of LAI, including the woody to total area ratio ([alpha]), the element clumping index ([[OMEGA].sub.E], using three different methods), and the photographic exposure setting (E). Before these corrections were made, [LAI.sub.DHP] underestimates [LAI.sub.dir] by 14%-55% from 21 May to 1 October but overestimates it by 78% on 12 May and by 226% on 11 October. Although pronounced differences are observed between [LAI.sub.dir] and [LAI.sub.DHP], they are significantly correlated ([R.sup.2] = 0.85, RMSE = 0.32, P < 0.001). After considering seasonal changes in [alpha], [[OMEGA].sub.E], and E, the accuracy of [LAI.sub.DHP] improves markedly, with a mean difference between the corrected [LAI.sub.DHP] and [LAI.sub.dir] of Key words: leaf area index, leaf phenology, litter collection, digital hemispherical photography (DHP), seasonal changes. Des methodes optiques ont ete largement utilisees pour estimer les variations saisonnieres de l'indice de surface foliaire (ISF) de peuplements forestiers en raison de leur commodite et de leur efficacite, mais leur precision dans les forets de feuillus decidus a rarement ete evaluee. Les variations saisonnieres de l'ISF ont ete estimees en combinant des observations periodiques de la variation de la surface foliaire a l'aide de recolte de litiere ([ISF.sub.dir]) dans des forets de feuillus decidus et en utilisant ces estimations pour evaluer la precision des mesures optiques de l'ISF faites a partir de photographies hemispheriques digitales (PHD). Nous proposons aussi une methode pour corriger les valeurs de l'ISF provenant de PHD ([ISF.sub.PHD]) en utilisant les changements saisonniers dans les principaux facteurs qui influencent la determination de l'ISF, incluant le rapport entre la surface ligneuse et la surface totale ([alpha]), l'indice d'agglomeration des elements ([[OMEGA].sub.E], selon trois methodes differentes) et le reglage de l'exposition photographique (E). Avant de faire ces corrections, les valeurs de [l'ISF.sub.PHD] sous-estimaient celles de [l'ISF.sub.dir] de 14 % a 55 % entre le 21 mai et le 1 octobre, mais les surestimaient de 78 % le 12 mai et de 226 % le 11 octobre. Bien que des differences importantes soient observees entre l'ISFdir et l'ISFPHD, ces variables sont significativement correlees ([R.sup.2] = 0,85, EMQ = 0,32, p < 0,001). Apres avoir pris en compte les variations saisonnieres de [alpha], [[OMEGA].sub.E] et E, la precision de l'ISFPHD a augmente considerablement; la difference moyenne entre les valeurs corrigees de l'ISFPHD et de [I'ISF.sub.dir] etait inferieure a 17 % pour toutes les periodes. Ces resultats indiquent que la methode proposee pour corriger l'ISFPHD est utile et efficace pour estimer la variation saisonniere de l'ISF dans les forets de feuillus decidus. [Traduit par la Redaction] Mots-cles: indice de surface foliaire, phenologie foliaire, recolte de litiere, photographie hemispherique digitale, changements saisonniers., 1. Introduction The leaf area index (LAI), defined as half the total green leaf area per unit ground surface area (Chen and Black 1992), is a major determinant of gross [...]