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Though aboveground biomass (AGB) has an important contribution to the global carbon cycle, the information about storage and climatic effects of AGB is scare in Three-River Source Region (TRSR) shrub ecosystems. This study investigated AGB storage and its climatic controls in the TRSR alpine shrub ecosystems using data collected from 23 sites on the Tibetan Plateau from 2011 to 2013. We estimated the AGB storage (both shrub layer biomass and grass layer biomass) in the alpine shrubs as 37.49 Tg, with an average density of 1447.31 g m<sup>-2</sup>. Biomass was primarily accumulated in the shrub layer, which accounted for 92% of AGB, while the grass layer accounted for only 8%. AGB significantly increased with the mean annual temperature (<i>P</i> < 0.05). The effects of the mean annual precipitation on AGB were not significant. These results suggest that temperature, rather than precipitation, has significantly effects on of aboveground vegetation growth in the TRSR alpine shrub ecosystems. The actual and potential increase in AGB density was different due to global warming varies among different regions of the TRSR. We conclude that long-term monitoring of dynamic changes is necessary to improve the accuracy estimations of potential AGB carbon sequestration across the TRSR alpine shrub ecosystems.
Five days of integrative body-mind training (IBMT) improves attention and self-regulation in comparison with the same amount of relaxation training. This paper explores the underlying mechanisms of this finding. We measured the physiological and brain changes at rest before, during, and after 5 days of IBMT and relaxation training. During and after training, the IBMT group showed significantly better physiological reactions in heart rate, respiratory amplitude and rate, and skin conductance response (SCR) than the relaxation control. Differences in heart rate variability (HRV) and EEG power suggested greater involvement of the autonomic nervous system (ANS) in the IBMT group during and after training. Imaging data demonstrated stronger subgenual and adjacent ventral anterior cingulate cortex (ACC) activity in the IBMT group. Frontal midline ACC theta was correlated with highfrequency HRV, suggesting control by the ACC over parasympathetic activity. These results indicate that after 5 days of training, the IBMT group shows better regulation of the ANS by a ventral midfrontal brain system than does the relaxation group. This changed state probably reflects training in the coordination of body and mind given in the IBMT but not in the control group. These results could be useful in the design of further specific interventions.
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Swertia mussotii Franch. and Swertia chirayita Buch.-Ham. have been commonly used under the same name "Zangyinchen" for the treatment of liver and gallbladder diseases in traditional Tibetan medicine. Detailed characterization and comparison of the complete set of metabolites of these two species are critical for their objective identification and quality control. In this study, a rapid, simple and comprehensive (1)H NMR-based metabolomics method was first developed to differentiate the two species. A broad range of metabolites, including iridoid glycosides, xanthones, triterpenoids, flavonoids, carbohydrates, and amino acids, were identified. Statistical analysis showed evident differences between the two species, and the major markers responsible for the differences were screened. In addition, quantitative (1)H NMR method (qHNMR) was used for the target analysis of the discriminating metabolites. The results showed that S. mussotii had significantly higher contents of gentiopicrin, isoorientin, glucose, loganic acid, and choline, whereas S. chirayita exhibited higher levels of swertiamarin, oleanolic acid, valine, and fatty acids. These findings indicate that (1)H NMR-based metabolomics is a reliable and effective method for the metabolic profiling and discrimination of the two Swertia species, and can be used to verify the genuine origin of Zangyinchen.
Swertia mussotii Franch. and Swertia chirayita Buch.-Ham. have been commonly used under the same name 'Zangyinchen' for the treatment of liver and gallbladder diseases in traditional Tibetan medicine. Detailed characterization and comparison of the complete set of metabolites of these two species are critical for their objective identification and quality control. In this study, a rapid, simple and comprehensive H-1 NMR-based metabolomics method was first developed to differentiate the two species. A broad range of metabolites, including iridoid glycosides, xanthones, triterpenoids, flavonoids, carbohydrates, and amino acids, were identified. Statistical analysis showed evident differences between the two species, and the major markers responsible for the differences were screened. In addition, quantitative H-1 NMR method (qHNMR) was used for the target analysis of the discriminating metabolites. The results showed that S. mussotii had significantly higher contents of gentiopicrin, isoorientin, glucose, loganic acid, and choline, whereas S. chirayita exhibited higher levels of swertiamarin, oleanolic acid, valine, and fatty acids. These findings indicate that H-1 NMR-based metabolomics is a reliable and effective method for the metabolic profiling and discrimination of the two Swertia species, and can be used to verify the genuine origin of Zangyinchen. (C) 2014 Elsevier B.V. All rights reserved.
<br>• A 1H NMR-based method is first developed to differentiate two <b>Swertia</b> species. • The two <b>Swertia</b> species exhibit significant differences in their metabolic profiling. • Nine metabolic markers responsible for the differences are screened out. • A qHNMR method is used for quantitative analysis of the discriminating metabolites. • The proposed 1H NMR-based metabolomics method is rapid, reliable and effective.<br><b>Swertia mussotii</b> Franch. and <b>Swertia chirayita</b> Buch.-Ham. have been commonly used under the same name “Zangyinchen” for the treatment of liver and gallbladder diseases in traditional Tibetan medicine. Detailed characterization and comparison of the complete set of metabolites of these two species are critical for their objective identification and quality control. In this study, a rapid, simple and comprehensive 1H NMR-based metabolomics method was first developed to differentiate the two species. A broad range of metabolites, including iridoid glycosides, xanthones, triterpenoids, flavonoids, carbohydrates, and amino acids, were identified. Statistical analysis showed evident differences between the two species, and the major markers responsible for the differences were screened. In addition, quantitative 1H NMR method (qHNMR) was used for the target analysis of the discriminating metabolites. The results showed that <b>S. mussotii</b> had significantly higher contents of gentiopicrin, isoorientin, glucose, loganic acid, and choline, whereas <b>S. chirayita</b> exhibited higher levels of swertiamarin, oleanolic acid, valine, and fatty acids. These findings indicate that 1H NMR-based metabolomics is a reliable and effective method for the metabolic profiling and discrimination of the two <b>Swertia</b> species, and can be used to verify the genuine origin of Zangyinchen.