Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i...Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.展开更多
Aim To study the chemical constituents from the stems of Xylosma controversum Clos. Methods The constituents were isolated by solvent extraction, repeated chromatography with silica gel, Sephadex LH-20, and RP-18 colu...Aim To study the chemical constituents from the stems of Xylosma controversum Clos. Methods The constituents were isolated by solvent extraction, repeated chromatography with silica gel, Sephadex LH-20, and RP-18 columns. The structures were elucidated by spectral analysis. Results Thirteen compounds were isolated and their structures were identified as （-）-syringaresinol （1）, syringaresinol-4-O-β-D-glucopyranoside （2）, syringaresinol-4,4′-bis-O-β-D-glucopyranoside （3）, （±）-catechin （4）, catechin-3-O- β-D-glucopyranoside （5）, catechin-5-O-β-D-glucopyranoside （6）, 1,3-bis-（4-hydroxy-3,5-dimethoxyphenyl）-1,3-propanediol （7）, （R）-（＋）-chaulmoogric acid （8）, friedelin （9）, uracile （10）, benzoic acid （11）, vaniUic acid （12）, and 4-hydroxybenzoic acid （13）. Conclusion All the compounds described above were isolated from this genus for the first time.展开更多
To investigate changes of functional activation areas of the cerebral cortex and the connectivity of motor cortex networks （MCNs） in stroke patients during the recovery, five patients with the infarct in their left ...To investigate changes of functional activation areas of the cerebral cortex and the connectivity of motor cortex networks （MCNs） in stroke patients during the recovery, five patients with the infarct in their left hemispheres are recruited. Functional magnetic resonance imaging （fMRI） is performed in the second, fourth, eighth, and sixteenth weeks after the stroke. Images are analyzed using the professional software SPM5 to obtain the bilateral activation of the motor cortex in left and right handgrip tests. MCN data are extracted from the active areas, and the structural and functional characteristic parameters are computed to indicate the connectivity of the network. Results show that the ipsilesional hemisphere recruits more areas with less active extent during the handgrip test, compared with the contralesional hemisphere. MCN shows a higher overall degree of statistical independence and more statistical dependence among motor areas with the gradual recovery. It can help physicians understand the recovery mechanism.展开更多
To investigate the chemical components of the barks and twigs ofltoa orientalis. A new linear monoterpene glycoside named itoside O was isolated from the crude extract of Itoa orientalis together with 11 known compoun...To investigate the chemical components of the barks and twigs ofltoa orientalis. A new linear monoterpene glycoside named itoside O was isolated from the crude extract of Itoa orientalis together with 11 known compounds. The new compound was identified to be 3,7-dimethyl-1, 6-octadien-3, 10-dihydroxyl-10-O-α-L-arabinopyranosyl （1 -→6）-O-β-D-glucopyranoside by 1D and 2D NMR analysis, and all known compounds were isolated from this plant for the first time.展开更多
In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes （side window, side window＋roof window） on the t...In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes （side window, side window＋roof window） on the temperature and humidity of plastic greenhouse were studied. The results showed that the ventilation mode of opening side window and roof window could effectively reduce the temperature and humidity at the plant canopy height, which was conducive to the growth of plant in greenhouse.展开更多
Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi＇an. Results indicate that, under similar weather circumstances, different events ...Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi＇an. Results indicate that, under similar weather circumstances, different events evidently exhibit unique vertical structure features. Informational digital diagrams provide a method for transitional weather prediction, a problem for present extrapolative analysis system.展开更多
基金supported by the 2nd Scientific Expedition to the Qinghai–Tibet Plateau[grant number 2019QZKK0102]the National Natural Science Foundation of China[grant number 42275045,41975012]+3 种基金the West Light Foundation of the Chinese Academy of Sciences[grant number xbzg-zdsys-202215]the Science and Technology Research Plan of Gansu Province[grant number 20JR10RA070]the Youth Innovation Promotion Association of the Chinese Academy of Sciences[grant number QCH2019004]iLEAPs(integrated Land Ecosystem–Atmosphere Processes Study).
文摘Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ.
基金Program for Changjiang Scholar and InnovativeTeam in Peking University (Grant number: 985-2-063-112).
文摘Aim To study the chemical constituents from the stems of Xylosma controversum Clos. Methods The constituents were isolated by solvent extraction, repeated chromatography with silica gel, Sephadex LH-20, and RP-18 columns. The structures were elucidated by spectral analysis. Results Thirteen compounds were isolated and their structures were identified as （-）-syringaresinol （1）, syringaresinol-4-O-β-D-glucopyranoside （2）, syringaresinol-4,4′-bis-O-β-D-glucopyranoside （3）, （±）-catechin （4）, catechin-3-O- β-D-glucopyranoside （5）, catechin-5-O-β-D-glucopyranoside （6）, 1,3-bis-（4-hydroxy-3,5-dimethoxyphenyl）-1,3-propanediol （7）, （R）-（＋）-chaulmoogric acid （8）, friedelin （9）, uracile （10）, benzoic acid （11）, vaniUic acid （12）, and 4-hydroxybenzoic acid （13）. Conclusion All the compounds described above were isolated from this genus for the first time.
基金Supported by the National Natural Science Foundation of China (30670543)~~
文摘To investigate changes of functional activation areas of the cerebral cortex and the connectivity of motor cortex networks （MCNs） in stroke patients during the recovery, five patients with the infarct in their left hemispheres are recruited. Functional magnetic resonance imaging （fMRI） is performed in the second, fourth, eighth, and sixteenth weeks after the stroke. Images are analyzed using the professional software SPM5 to obtain the bilateral activation of the motor cortex in left and right handgrip tests. MCN data are extracted from the active areas, and the structural and functional characteristic parameters are computed to indicate the connectivity of the network. Results show that the ipsilesional hemisphere recruits more areas with less active extent during the handgrip test, compared with the contralesional hemisphere. MCN shows a higher overall degree of statistical independence and more statistical dependence among motor areas with the gradual recovery. It can help physicians understand the recovery mechanism.
基金Program for Changjiang Scholar and Innovative Team in University (Grant No. 985-2-063-112)
文摘To investigate the chemical components of the barks and twigs ofltoa orientalis. A new linear monoterpene glycoside named itoside O was isolated from the crude extract of Itoa orientalis together with 11 known compounds. The new compound was identified to be 3,7-dimethyl-1, 6-octadien-3, 10-dihydroxyl-10-O-α-L-arabinopyranosyl （1 -→6）-O-β-D-glucopyranoside by 1D and 2D NMR analysis, and all known compounds were isolated from this plant for the first time.
基金Supported by Jiangsu Agricultural Science and Technology Innovation Fund[CX(14)2112]~~
文摘In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes （side window, side window＋roof window） on the temperature and humidity of plastic greenhouse were studied. The results showed that the ventilation mode of opening side window and roof window could effectively reduce the temperature and humidity at the plant canopy height, which was conducive to the growth of plant in greenhouse.
文摘Using informational digital diagrams, we analyzed the snow event that occurred on Feb 26, 2006 and the sandstorm on Apr 11, 2006 in Xi＇an. Results indicate that, under similar weather circumstances, different events evidently exhibit unique vertical structure features. Informational digital diagrams provide a method for transitional weather prediction, a problem for present extrapolative analysis system.
