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This study was performed to observe the effects of water on photosynthesis and water-related physiology in dominant shrubs in shell sand habitats. Four-year-old Periploca sepium seedlings were used as model species. A gradient of 12 water levels was established by artificially supplying the shell sand with water up to saturation and then allowing natural evapotranspiration to occur. The photosynthetic, chlorophyll fluorescence and stem sap flow parameters of P. sepium were measured under a range of water conditions. The different soil water conditions were classified according to the responses of these parameters. (1) With the increase in the relative water content (RWC) of the shell sand, the parameters of leaf photosynthesis, chlorophyll fluorescence and water-related physiology in P. sepium showed significant critical responses. The net photosynthetic rate (Pn), transpiration rate (Tr), instantaneous water use efficiency (WUE), potential water use efficiency (WUEi), maximum photochemical efficiency (Fv/Fm), actual photochemical efficiency (ΦPSII) and daily accumulation of stem sap flow all increased first and then decreased with increasing RWC, but the corresponding water conditions associated with their maximum values were not the same. An RWC of 69.40% was determined to be the optimal water condition for photosynthesis and water-related physiological activity in P. sepium. At an RWC of 36.61%, the mechanism of photosynthetic inhibition in P. sepium changed from stomatal limitation to nonstomatal limitation; this was also the minimum water requirement for maintaining normal photosynthetic processes. An RWC of 50.27% resulted in the highest WUE in P. sepium, indicating that moderate drought stress increased WUE. (2) Based on the quantitative relationship between the photosynthetic parameters of P. sepium and the shell sand water gradient, the soil water availability was classified into 6 water grades. The RWC range for maintaining strong photosynthesis and high WUE in P. sepium was 63.22–69.98%. (3) Gas exchange in P. sepium was inhibited under drought and waterlogging stresses. Under these conditions, the photosynthetic electron transport chain was blocked, and the dissipation of light energy as heat increased, which ultimately led to a decline in photosynthetic productivity; moreover, transpiration and dissipation were aggravated, and water transmission and utilization processes in P. sepium were hindered. A significant negative feedback regulation mechanism in the photosynthetic and water-related physiological processes of P. sepium was observed; this mechanism allowed P. sepium growing in shell sand to be highly adaptable to water stress. [ABSTRACT FROM AUTHOR]

Most mental health problems develop during childhood and adolescence, so identifying the mental health needs and care pathways of adolescents is crucial to improving prevention. This study aimed to understand the characteristics of adolescent patients with mental disorders receiving psychotherapy in China. Data were collected retrospectively from the psychotherapy records of 116 patients at the Weifang Mental Health Centre. Information collected included demographics, stressors, duration of psychotherapy, and clinical diagnosis. Chi-square tests and negative binomial regression models were used to explore the relationship between demographic and clinical variables. The results showed that depression was the most common diagnosis, followed by anxiety and stress-related disorders and bipolar and related disorders. Rural patients were more likely to report family stress, while urban patients were more likely to report school stress. Female patients were more likely to report family stress and to be diagnosed with depression. Family stress, social stress, school stress, patient origin and economic conditions were all significant predictors of the duration of psychological treatment. This study helps to understand the characteristics and psychotherapeutic needs of adolescents with mental disorders who receive psychotherapy in China so that the positive role of psychotherapy in the prevention, treatment and rehabilitation of mental disorders can be better utilised. [ABSTRACT FROM AUTHOR]

Plant-derived allelochemicals have the potential to be used as eco-friendly measures for control of Microcystis aeruginosa blooms. However, the susceptibility of M. aeruginosa to plant allelochemicals under a range of environmental factors, such as alkalinity, is not clear. This study investigated the effects of different alkalinity treatments on 1,2,3-trihydroxybenzene (pyrogallol) toxicity to a toxic strain of the cyanobacterium, M. aeruginosa (FACHB 905). Pyrogallol toxicity to M. aeruginosa cultures, both pre-adapted to a range of alkalinity levels and un-adapted, increased when alkalinity was increased from 0.09 to 1.51 meq L−1. The mean inhibition ratios calculated according to OD650, cell concentration, Chl a, and carotenoid concentrations of M. aeruginosa cultures were highest in the highest alkalinity treatment (1.51 meq L−1), i.e., up to 74%, 80%, 73%, and 87% for alkalinity-adapted cells on day 3. The lowest cell concentrations and photosynthesis pigment concentrations were found in the highest alkalinity treatment (1.51 meq L−1) for un-adapted cells in 12-day bioassays. This trend was more obvious over time. Pyrogallol and TPC (total phenolic compounds) concentrations measured immediately after pyrogallol addition into the culture medium decreased more rapidly in higher alkalinity treatments. In contrast, faster oxygen consumption and higher production of quinone end products occurred within the first 30 min after pyrogallol addition at higher alkalinity levels. Quinones and oxygen radicals have been shown previously to be more toxic to cyanobacteria than pyrogallol itself. This provides a potential explanation for the enhanced pyrogallol toxicity to M. aeruginosa under higher alkalinity. Therefore, it is important to take alkalinity into account when considering pyrogallol as a potential biocide. [ABSTRACT FROM AUTHOR]

The chemical constituents of fistular onion stalk obtained by supercritical CO2 extraction were separated and purified by silica gel and sephadex LH-20 gel column chromatography and the preparative TLC method and four flavonoids were obtained. On the basis of the spectral data, they were structurally identified as (+)-catechin, (−)-epicatechin, astragalin, and 3-O-β-D(2-O-β-D-glucopyranosyl)-glucopyranosides of kaempferol. [ABSTRACT FROM AUTHOR]

In the first paragraph, this sentence was cited incorrectly. The cited work was done by Nogita et al. Importantly, the density changes with the structural evolutions. It may be catastrophic to the intrinsically brittle IMC as reported by Nogita et al. that more cracks were observed at the interface of Sn-Cu/Cu if no Ni was added to inhibit the transformation.4 The correct citation is as follows: Importantly, the density changes with the structural evolutions. It may be catastrophic to the intrinsically brittle IMC as reported by Nogita et al. that more cracks were observed at the interface of Sn-Cu/Cu if no Ni was added to inhibit the transformation.8 The publisher regrets the error. [ABSTRACT FROM AUTHOR]