The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. W...The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny.展开更多
A new triterpenoid saponin, namely pomatoside A (3) 13beta, 28-epoxy-16-oleananone-3-O-[alpha-L-rhamnopyranosyl-(1 -->6)-O-beta-D-glucopyranosyl-(1 -->4)-O-beta-D-glucopyranosyl-(1 -->6)-O-beta-D-glucopyranos...A new triterpenoid saponin, namely pomatoside A (3) 13beta, 28-epoxy-16-oleananone-3-O-[alpha-L-rhamnopyranosyl-(1 -->6)-O-beta-D-glucopyranosyl-(1 -->4)-O-beta-D-glucopyranosyl-(1 -->6)-O-beta-D-glucopyranosyl-(1 -->2)]-beta-D-glucopyranoside, together with twelve known compounds, was isolated for the first time from Pomatosace filicula Maxim., a monotypic endemic plant, grown in the Qinghai-Xizang Plateau of China. Their structures were elucidated by spectroscopic analyses and chemical methods, especially 2D-NMR.展开更多
The potential predictability and skill of Eurasian spring snow water equivalent(SWE)are explored by using a suite of ensemble hindcast experiments with the fourth-generation IAP AGCM(IAP AGCM4)and observations for the...The potential predictability and skill of Eurasian spring snow water equivalent(SWE)are explored by using a suite of ensemble hindcast experiments with the fourth-generation IAP AGCM(IAP AGCM4)and observations for the period 1982–2012.IAP AGCM4 is generally capable of reproducing the spatial distribution of Eurasian spring SWE;nevertheless,the model overestimates the SWE over Eurasia,possibly because of positive precipitation biases in wintertime.IAP AGCM4 can successfully capture the long-term trend and leading pattern of Eurasian spring SWE.Additionally,the spring SWE anomalies are generally predictable in many regions over Eurasia,especially at high latitudes;moreover,IAP AGCM4 exhibits a remarkable prediction skill for spring SWE anomalies over Eurasia in many years during 1982 to 2012.In order to reveal the relative impacts of SST anomalies and atmospheric initial conditions on the seasonal predictability of Eurasian spring SWE,two additional sets of experiments are carried out.Overall,atmospheric initial anomalies have a dominant role,though the impact of SSTs is not negligible.This study highlights the importance of atmospheric initialization in seasonal climate forecasts of spring SWE anomalies,especially at high latitudes.展开更多
Recent studies have revealed that two boreal spring sea surface temperature （SST） indices have potential to predict the number of western North Pacific （WNP） tropical cyclones （TCs） in the following peak typhoon...Recent studies have revealed that two boreal spring sea surface temperature （SST） indices have potential to predict the number of western North Pacific （WNP） tropical cyclones （TCs） in the following peak typhoon season （June-October）： the northern tropical Atlantic （NTA） SST, and the SST gradient （SSTG） between the southwestern Pacific and western Pacic warm pool. The interannua[ and interdecadal variations of NTA SST and SSTG and their relationships to the number ofWNP TCs during 1950-2013 were compared. On the interdecadal timescale, SSTG showed better correlation with the number of WNP TCs than NTA SST. The interdecadal variation of NTA SST was closely associated with the Atlantic Multidecadal Oscillation, while that of SSTG was anti-correlated with the Central Pacific （CP） El Nino index at the interdecadal timescale. On the interannual timescale, both NTA SST and SSTG were modulated by two types of El Nino. The NTA SST revealed significant correlations with the number of WNPTCs beginning from the early 1960s; by contrast, SSTG showed significant correlations after the mid-1970s. Co-variability of NTA SST and SSTG existed after the late 1980s, induced by modulation from CP El Nino.The co-variability of these two spring SST predictors increased their prediction skill after the late 1980s, with enhanced correlation between the number of WNPTCs and the two predictors.展开更多
文摘The circumscriptions of sections Auganthus Pax ex Balf. f. and Ranunculoides Chen et C. M. Hu in the genus Primula L. have been controversial, due to the different treatments of P. filchnerae Knuth. We conducted a phylogenetic analysis using sequences from the ITS region of nuclear ribosomal DNA. All five species of these two sections and some representatives of other related sections were sampled. The ITS trees show that P. filchnerae could be convincingly placed in sect. Auganthus , together with P. sinensis Sabine ex Lindl. and P. rupestris Balf. f. et Farrer, whereas sect. Ranunculoides contains two species: P. cicutariifolia Pax and P. merrilliana Schltr. These two sections are distantly related and their association with other sections needs further studies. This study also demonstrated that ITS sequences would be a suitable marker for the reconstruction of Primula phylogeny.
文摘A new triterpenoid saponin, namely pomatoside A (3) 13beta, 28-epoxy-16-oleananone-3-O-[alpha-L-rhamnopyranosyl-(1 -->6)-O-beta-D-glucopyranosyl-(1 -->4)-O-beta-D-glucopyranosyl-(1 -->6)-O-beta-D-glucopyranosyl-(1 -->2)]-beta-D-glucopyranoside, together with twelve known compounds, was isolated for the first time from Pomatosace filicula Maxim., a monotypic endemic plant, grown in the Qinghai-Xizang Plateau of China. Their structures were elucidated by spectroscopic analyses and chemical methods, especially 2D-NMR.
基金This work was jointly supported by the Strategic Priority Research Program of the Chinese Academy of Sciences[grant number XDA19030403]the National Natural Science Foundation of China[grant number 41575080].
文摘The potential predictability and skill of Eurasian spring snow water equivalent(SWE)are explored by using a suite of ensemble hindcast experiments with the fourth-generation IAP AGCM(IAP AGCM4)and observations for the period 1982–2012.IAP AGCM4 is generally capable of reproducing the spatial distribution of Eurasian spring SWE;nevertheless,the model overestimates the SWE over Eurasia,possibly because of positive precipitation biases in wintertime.IAP AGCM4 can successfully capture the long-term trend and leading pattern of Eurasian spring SWE.Additionally,the spring SWE anomalies are generally predictable in many regions over Eurasia,especially at high latitudes;moreover,IAP AGCM4 exhibits a remarkable prediction skill for spring SWE anomalies over Eurasia in many years during 1982 to 2012.In order to reveal the relative impacts of SST anomalies and atmospheric initial conditions on the seasonal predictability of Eurasian spring SWE,two additional sets of experiments are carried out.Overall,atmospheric initial anomalies have a dominant role,though the impact of SSTs is not negligible.This study highlights the importance of atmospheric initialization in seasonal climate forecasts of spring SWE anomalies,especially at high latitudes.
基金funded by the Guangdong Natural Science Foundation[grant number 2015A030313796]the National Natural Science Foundation of China[grant numbers 41205026,41476009,41476010]+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences[grant number Xd A11010104]the National Program on Global Change and Air-Sea interaction[grant number GASi-i POVAi-04]the Knowledge innovation Program of the Chinese Academy of Sciences[grant number SQ201208]
文摘Recent studies have revealed that two boreal spring sea surface temperature （SST） indices have potential to predict the number of western North Pacific （WNP） tropical cyclones （TCs） in the following peak typhoon season （June-October）： the northern tropical Atlantic （NTA） SST, and the SST gradient （SSTG） between the southwestern Pacific and western Pacic warm pool. The interannua[ and interdecadal variations of NTA SST and SSTG and their relationships to the number ofWNP TCs during 1950-2013 were compared. On the interdecadal timescale, SSTG showed better correlation with the number of WNP TCs than NTA SST. The interdecadal variation of NTA SST was closely associated with the Atlantic Multidecadal Oscillation, while that of SSTG was anti-correlated with the Central Pacific （CP） El Nino index at the interdecadal timescale. On the interannual timescale, both NTA SST and SSTG were modulated by two types of El Nino. The NTA SST revealed significant correlations with the number of WNPTCs beginning from the early 1960s; by contrast, SSTG showed significant correlations after the mid-1970s. Co-variability of NTA SST and SSTG existed after the late 1980s, induced by modulation from CP El Nino.The co-variability of these two spring SST predictors increased their prediction skill after the late 1980s, with enhanced correlation between the number of WNPTCs and the two predictors.
