He X., Ren Z., An B., 2017. The tree-species-specific effect of forest bathing on perceived anxiety alleviation of young-adults in urban forests. Ann. For. Res. 60(2): 327-341.Abstract. Forest bathing, i.e. spending time in a forest to walk, view and breathe in a forest, can alleviate the mental depression of visitors, but the tree-species-specific effect of this function by the urban forest is unknown. In this study, sixty-nine university students (aged 19-22, male ratio: 38%) were recruited as participants to visit urban forests dominated by birch (Betula platyphylla Suk.), maple (Acer triflorum Komarov) and oak (Quercus mongolica Fisch. ex Ledeb) trees in a park at the center of Changchun City, Northeast China. In the maple forest only the anxiety from study interest was decreased, while the anxiety from employment pressure was alleviated to the most extent in the birch forest. Participants perceived more anxiety from lesson declined in the oak forest than in the birch forest. Body parameters of weight and age were correlated with the anti-anxiety scores. In the oak forest, female participants can perceive more anxiety alleviation than male participants. For university students, forest bathing in our study can promote their study interest. Forest bathing can be more effective to alleviate the anxiety of young adults with greater weight. The birch forest was recommended to be visited by students to alleviate the pressure of employment worry, and the oak forest was recommended to be visited by girls.

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In this study, we investigated the mechanism of photosynthesis and physiological function of blueberry leaves under low temperature stress (4-6°C) by exogenous hydrogen sulfide (H 2 S) by spraying leaves with 0.5 mmol·L -1 NaHS (H 2 S donor) and 200 mmol·L -1 hypotaurine (Hypotaurine, H 2 S scavenger). The results showed that chlorophyll and carotenoid content in blueberry leaves decreased under low temperature stress, and the photochemical activities of photosystem II (PSII) and photosystem I (PSI) were also inhibited. Low temperature stress can reduce photosynthetic carbon assimilation capacity by inhibiting stomatal conductance (G s ) of blueberry leaves, and non-stomatal factors also play a limiting role at the 5 th day of low temperature stress. Low temperature stress leads to the accumulation of Pro and H 2 O 2 in blueberry leaves and increases membrane peroxidation. Spraying leaves with NaHS, a donor of exogenous H 2 S, could alleviate the degradation of chlorophyll and carotenoids in blueberry leaves caused by low temperature and reduce the photoinhibition of PSII and PSI. The main reason for the enhancement of photochemical activity of PSII was that exogenous H 2 S promoted the electron transfer from Q A to Q B on PSII acceptor side under low temperature stress. In addition, it promoted the accumulation of osmotic regulator proline under low temperature stress and significantly alleviated membrane peroxidation. H 2 S scavengers (Hypotaurine) aggravated photoinhibition and the degree of oxidative damage under low temperature stress. Improving photosynthetic capacity as well as alleviating photosynthetic inhibition and oxidative stress with exogenous H 2 S is possible in blueberry seedlings under low temperature stress.

Tang & Baiyi An (2019) Increased CO 2 concentrations increasing water use efficiency and improvement PSII function of mulberry seedling leaves under drought stress,

CYP82E4, a cytochrome P450 monooxygenase, has nicotine N-demethylase (NND) activity, which mediates the bioconversion of nicotine into nornicotine in senescing tobacco leaves. Nornicotine is a precursor of the carcinogen, tobacco-specific nitrosamine. CYP82E3 is an ortholog of CYP82E4 with 95% sequence identity, but it lacks NND activity. A recent site-directed mutagenesis study revealed that a single amino acid substitution, i.e., cysteine to tryptophan at the 330 position in the middle of protein, restores the NND activity of CYP82E3 entirely. However, the same amino acid change caused the loss of the NND activity of CYP82E4. To determine the mechanism of the functional turnover of the two molecules, four 3D structures, i.e., the two molecules and their corresponding cys–trp mutants were modeled. The resulting structures exhibited that the mutation site is far from the active site, which suggests that no direct interaction occurs between the two sites. Simulation studies in different biological scenarios revealed that the mutation introduces a conformation drift with the largest change at the F-G loop. The dynamics trajectories analysis using principal component analysis and covariance analysis suggests that the single amino acid change causes the opening and closing of the transfer channels of the substrates, products, and water by altering the motion of the F-G and B-C loops. The motion of helix I is also correlated with the motion of both the F-G loop and the B-C loop and; the single amino acid mutation resulted in the curvature of helix I. These results suggest that the single amino acid mutation outside the active site region may have indirectly mediated the flexibility of the F-G and B-C loops through helix I, causing a functional turnover of the P450 monooxygenase.