The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold ...The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs, The bacterial clones could be classified into Proteobacteria, Acid- obacteria, Deinococci, Sphingobacteria, Flavobacteria, Nitrospirae, Actinobacteria, Gemmatimona- detes, and unclassified-bacteria; and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota. Among the major groups, Proteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries, respectively. The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats, such as snow/ice/soils on high mountains or at high latitude. Especially, the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations. The data presented in this study have impli- cations for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau.展开更多
The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained o...The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained or strengthened in a stable manner.The delivery of accumulated cold air toward southeast was along the northwest airstream before the ridge.Therefore,the ridge of high pressure over Lake Baikal provided access for the cold air southward so that the cold air could continue to decline,resulting in the appearance of low temperature in late April and formation of 'late spring coldness'.The Northeast cold vortex(NECV) occurred frequently in mid May.There was a high possibility for low temperature and pluvial damages over Dalian.Thus the phenomenon of 'late spring coldness' appeared again.展开更多
A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecost...A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecosterigmatocystin(8),arugosin C(9),curvularin(10),3,3'-diindolylmethane(11),austinol(12),austin(13),and dehydroaustin(14),were isolated and identified from the culture extract of Aspergillus nidulans SD-531,a fungus obtained from the deep-sea sediment of cold spring in the South China Sea.Their structures were determined based on detailed interpretation of nuclear magnetic resonance(NMR)spectroscopic and mass spectrometry data analysis.All the isolated compounds were evaluated for antimicrobial activities against human and aquatic bacteria as well as plant pathogenic fungi.Compounds 1–8,10,and 11 exhibited antimicrobial activities against some of the tested strains with minimum inhibitory concentration(MIC)values ranging from^2 to 64μg/mL.Compounds 4 and 6 displayed strongest activities among the tested samples and might be used as promising molecules for the development of natural antimicrobial agents.展开更多
The use of ocean bottom seismometers provides an effective means of studying the process and the dynamic of cold seeps by continuously recording micro-events produced by sub-seafloor fluid migration.We deployed a four...The use of ocean bottom seismometers provides an effective means of studying the process and the dynamic of cold seeps by continuously recording micro-events produced by sub-seafloor fluid migration.We deployed a four-component Ocean Bottom Seismometer(OBS)at an active site of the Haima cold seep from 6 November to 19 November in 2021.Here,we present the results of this short-term OBS monitoring.We first examine the OBS record manually to distinguish(by their distinctive seismographic signatures)four types of events:shipping noises,vibrations from our remotely operated vehicle(ROV)operations,local earthquakes,and short duration events(SDEs).Only the SDEs are further discussed in this work.Such SDEs are similar to those observed in other sea areas and are interpreted to be correlated with sub-seafloor fluid migration.In the OBS data collected during the 14-day monitoring period.We identify five SDEs.Compared to the SDE occurrence rate observed in other cold seep regions,five events is rather low,from which it could be inferred that fluid migration,and subsequent gas seepage,is not very active at the Haima site.This conclusion agrees with multi-beam and chemical observations at that site.Our observations thus provide further constraint on the seepage activity in this location.This is the first time that cold seep-related SDEs have been identified in the South China Sea,expanding the list of sea areas where SDEs are now linked to cold seep fluid migration.展开更多
This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies...This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs.展开更多
Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses o...Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.展开更多
Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because th...Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because that the high geopotential height near Ural Mountains lasted for a long time, while the geopotential height was abnormally low in the east of central Asia. Meanwhile, the Iow-prassure trough in the south of Qinghai -Tibet Plateau was very active and moved towards the east frequently, and subtropical high was strong. Compared with continuous rainy and cold weather in early 2008, during the process of this continuous rainy and cold weather in 2009, the decrease in sea surface temperature of the middle and eastern Pacific Ocean near the equator was weaker; the blocking high pressure was slightly weaker, and the low pressure over Mongolia was strong; subtropical high was stronger and showed zonal distribution; south trough was slightly weaker. Compared with the previous continuous rainy and cold weather, the duration of this continuous rainy and cold weather in 2009 was not the longest, and its sunshine hours were not the least, but its temperature was higher, which might result from obvious increase of temperature in the early days. The research could provide scientific references for the prediction of continuous rainy and cold weather in future.展开更多
Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an an...Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an ancient city known as the Venice of China, famous for its canals and private gardens and home to scholars for more than two millenia.展开更多
The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the confere...The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the conference provide ample opportunity forinformal interactions.Major topics on the conference include:neurogenesis,axon guidance,synapse formation,dendritemorphogenesis,developmental plasticity。展开更多
Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in ...Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.展开更多
Changes in isozymes of peroxidase, catalase, superoxide dismutase, polyphenol oxidase, and esterase and activities of per- oxidase and polyphenol oxidase in two annual Brassica varieties (AS-3 and CON, cold-tolerant ...Changes in isozymes of peroxidase, catalase, superoxide dismutase, polyphenol oxidase, and esterase and activities of per- oxidase and polyphenol oxidase in two annual Brassica varieties (AS-3 and CON, cold-tolerant and cold-sensitive, respectively) after 4℃ treatment were assayed. After the low temperature treatment, PAGE patterns of isozymes of peroxidase, catalase, superoxide dismutase, polyphenol oxidase, and esterase showed that the expressions and activities of these enzymes in the AS-3 variety were higher than the CON variety. Under normal and cold conditions, peroxidase and esterase activities of AS-3 were higher than those of CON. The relative freezing tolerance of these two cultivars was discussed.展开更多
To better understand the dust storm (hereafter DS) inducing circulation in the China-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS...To better understand the dust storm (hereafter DS) inducing circulation in the China-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS area for the majorandminor-DS years have,as a whole (not partly),been analyzed,utilizing the National Centers for Environmental Prediction and the National Center for Atmospheric Research (NCEP/NCAR) reanalyzed gridded data,the observed DS frequency data in the CM area,and the composite analysis method.The main conclusions are as follows:(1) Judging from the differences in the DS-inducing systems,dust origins,paths of invading cold air,and main DS-strike areas,the whole CM DS area is roughly divided into the three subre-gions:the East-,Middleand West-CM subregions (in this paper,referred to as E-,M-,and W-CM).(2) In major DSs during spring over the E-CM,the middleand lower-level troughs or cyclones over the Japan Sea and northeastern China (NEC) domi-nate.The invading cold air along the northeastern (NE) or north by east (NE) path often causes the DS in the E-CM region.But nearly the opposite is true inminor DS during spring in E-CM.(3) In the major DS during spring over the M-CM region,the Mongolian troughs or cyclones are the main DS-inducing systems.The strong invading cold air along the northwestern (NW)or north by west (Nw) path causes the DSs in the M-CM region.(4) In the major DSs during spring over the W-CM region,the South Xinjiang heat lows prevail,the intruding cold air has a western path,and creates the DSs in South Xinjiang.(5) In the past 50 years,the DSs over the M-CM region have had the most severe impact on the preceding three subregions of the CM DS area.Overall,DS activities over all of three regions of the CM area decreased in the past (particularly,over Mand W-CM regions since the mid-1980s.But there existed a short and sudden increasing in E-CM in the years 2000-2002.(6) It is circulation changes and desertification evolutions that cause the yearly and decadal changes of DS in CM area,especially the former.With the backdrop of global warming in the future,perhaps the decreased DS activities over Mand W-CM will persist for some time again,and special attention should be paid to ones over E-CM or to the individual DS events over Mand W-CM.展开更多
Cold seeps spread worldwide along the continental margins,which are closely related to the exploration of gas hydrates.Cold-seep carbonates have been reported to record the nature of seepage,including fluid source,sed...Cold seeps spread worldwide along the continental margins,which are closely related to the exploration of gas hydrates.Cold-seep carbonates have been reported to record the nature of seepage,including fluid source,sedimentary environment,and variation of seepage activity.We investigated the morphology,mineralogy,element compositions,and carbon and oxygen isotopes of 15 cold-seep carbonates collected from the Shenhu area,and compared them with 2 carbonates from the Haima cold seep,the South China Sea(SCS),to promote our knowledge of cold-seep system in SCS.Most of the Shenhu carbonates exhibit crust morphology,and some are in the form of chimneys and blocks.Their absolute(20%–65%)and relative carbonate mineral contents(mainly aragonite and calcite,with minor samples containing dolomite)vary significantly,indicating the multi-stage methane leakage in our study area.Some samples show a slight negative Ce anomaly,suggesting either the mixing of seawater or variation of the redox condition during the precipitation;the cooccurrence of strongly enriched U and Mo demonstrates anoxic condition during precipitation.The mixed genetic methane source was interpreted by δ^(13)C of the Shenhu carbonates to range from-22.34‰to-59.30‰Vienna PeeDee Belemnite(VPDB),and the slight ^(18)O-enrichment imprinted on the carbonates suggests the possible influence from hydrate dissociation.The Haima carbonates,with biogenic methane as the main gas source,were presumably formed in a stronger fluid flux by compared with our Shenhu samples.展开更多
Electrocardiogram(ECG)electrodes are conductive pads applied to the skin to measure cardiac activity.Ag/AgCl electrodes are the commercial product which widely used to obtain ECGs.When monitoring the ECG in a hot spri...Electrocardiogram(ECG)electrodes are conductive pads applied to the skin to measure cardiac activity.Ag/AgCl electrodes are the commercial product which widely used to obtain ECGs.When monitoring the ECG in a hot spring,Ag/AgCl electrodes must be waterproofed;however,this is time-consuming,and the adhesive may tear the skin on removal.For solving the problem,we developed the carbon pencil lead(CPL)electrodes for use in hot springs.Both CPL and Ag/AgCl electrodes were connected to ECG100C’s cables.The Performance was evaluated in three conditions as following:hot spring water with and without bubble,and in cold water.In each environment,the procedure was followed by three different protocols that are recording from the dry condition,hot spring water immersion with and without movement,post hot spring water condition.Under dry and wet conditions,both electrodes can obtain the waveform of the ECG signal in which all PQRST waves were identifiable.Nevertheless,the signal quality of both types of electrodes was different in water immersion with and without movement.The overall morphology obtained by Ag/AgCl electrodes was unstable higher than that of CPL electrodes in immersion without movement condition.The CPL electrodes provided better ECG waveform quality compared to Ag/AgCl electrodes in which the ECG signal had high waveforms distortion in water immersion with movement condition.展开更多
基金supported by grants from National Science Foundation of China(Grant Nos.41030211 and 41002123)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Edncation Ministry,Research Fund for the Doctoral Program of Higher Education of China(Grant No. 20100022120009)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.2010ZY16 and 2011YXL03)the Teaching Laboratory Funds from China University of Geosciences,Beijing
文摘The microbial diversity in Wuli Area, Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses. A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs, The bacterial clones could be classified into Proteobacteria, Acid- obacteria, Deinococci, Sphingobacteria, Flavobacteria, Nitrospirae, Actinobacteria, Gemmatimona- detes, and unclassified-bacteria; and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota. Among the major groups, Proteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries, respectively. The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats, such as snow/ice/soils on high mountains or at high latitude. Especially, the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations. The data presented in this study have impli- cations for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau.
文摘The NCEP data were applied to analyze causes of 'late spring coldness' occurring twice in Dalian in late April and mid May of 2008.The results showed that the 500 hPa Baikal ridge of high pressure maintained or strengthened in a stable manner.The delivery of accumulated cold air toward southeast was along the northwest airstream before the ridge.Therefore,the ridge of high pressure over Lake Baikal provided access for the cold air southward so that the cold air could continue to decline,resulting in the appearance of low temperature in late April and formation of 'late spring coldness'.The Northeast cold vortex(NECV) occurred frequently in mid May.There was a high possibility for low temperature and pluvial damages over Dalian.Thus the phenomenon of 'late spring coldness' appeared again.
基金the National Key R&D Program of China(No.2018YFC0310800)。
文摘A new acyclic peroxide derivative asperoxide A(1),along with 13 known compounds,namely,microperfuranone(2),9-hydroxymicroperfuranone(3),gibellulin A(4),lecanoric acid(5),terrequinone A(6),sterigmatocystin(7),isosecosterigmatocystin(8),arugosin C(9),curvularin(10),3,3'-diindolylmethane(11),austinol(12),austin(13),and dehydroaustin(14),were isolated and identified from the culture extract of Aspergillus nidulans SD-531,a fungus obtained from the deep-sea sediment of cold spring in the South China Sea.Their structures were determined based on detailed interpretation of nuclear magnetic resonance(NMR)spectroscopic and mass spectrometry data analysis.All the isolated compounds were evaluated for antimicrobial activities against human and aquatic bacteria as well as plant pathogenic fungi.Compounds 1–8,10,and 11 exhibited antimicrobial activities against some of the tested strains with minimum inhibitory concentration(MIC)values ranging from^2 to 64μg/mL.Compounds 4 and 6 displayed strongest activities among the tested samples and might be used as promising molecules for the development of natural antimicrobial agents.
基金supported by the Key Research and Development Project of Guangdong Province(Grant:2020B1111510001)supported by the Project of Sanya Yazhou Bay Science and Technology City(Grant No:SCKJ-JYRC-2022-14)the National Natural Science Foundation of China(Grant No:92262304).
文摘The use of ocean bottom seismometers provides an effective means of studying the process and the dynamic of cold seeps by continuously recording micro-events produced by sub-seafloor fluid migration.We deployed a four-component Ocean Bottom Seismometer(OBS)at an active site of the Haima cold seep from 6 November to 19 November in 2021.Here,we present the results of this short-term OBS monitoring.We first examine the OBS record manually to distinguish(by their distinctive seismographic signatures)four types of events:shipping noises,vibrations from our remotely operated vehicle(ROV)operations,local earthquakes,and short duration events(SDEs).Only the SDEs are further discussed in this work.Such SDEs are similar to those observed in other sea areas and are interpreted to be correlated with sub-seafloor fluid migration.In the OBS data collected during the 14-day monitoring period.We identify five SDEs.Compared to the SDE occurrence rate observed in other cold seep regions,five events is rather low,from which it could be inferred that fluid migration,and subsequent gas seepage,is not very active at the Haima site.This conclusion agrees with multi-beam and chemical observations at that site.Our observations thus provide further constraint on the seepage activity in this location.This is the first time that cold seep-related SDEs have been identified in the South China Sea,expanding the list of sea areas where SDEs are now linked to cold seep fluid migration.
基金jointly supported by the National Key R&D Program of China [grant number 2016YFA0600701]the National Natural Science Foundation of China [grant numbers41675083 and 41210007]the CAS–PKU Joint Research Program
文摘This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving processes.During an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily temperatures.In fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the ESCS.The anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ESCS.Then,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North China.In the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an end.The results may prove meaningful for the prediction and early warning of ESCSs.
基金supported by the National Key Research and Development Program of China (2017YFD0300408)the Major Research Projects of Anhui (202003b06020021)the Graduate Innovation Fund of Anhui Agricultural University (2020 ysj-5)。
文摘Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.
文摘Continuous rainy and cold weather in Yiwu in early spring of 2009 was analyzed. The results showed that the continuous rainy and cold weather occurred after temperature increased in early days. It is mainly because that the high geopotential height near Ural Mountains lasted for a long time, while the geopotential height was abnormally low in the east of central Asia. Meanwhile, the Iow-prassure trough in the south of Qinghai -Tibet Plateau was very active and moved towards the east frequently, and subtropical high was strong. Compared with continuous rainy and cold weather in early 2008, during the process of this continuous rainy and cold weather in 2009, the decrease in sea surface temperature of the middle and eastern Pacific Ocean near the equator was weaker; the blocking high pressure was slightly weaker, and the low pressure over Mongolia was strong; subtropical high was stronger and showed zonal distribution; south trough was slightly weaker. Compared with the previous continuous rainy and cold weather, the duration of this continuous rainy and cold weather in 2009 was not the longest, and its sunshine hours were not the least, but its temperature was higher, which might result from obvious increase of temperature in the early days. The research could provide scientific references for the prediction of continuous rainy and cold weather in future.
文摘Overview Cold Spring Harbor Asia conferences will be held at Suzhou Dushu Lake Conference Center in Suzhou, China, sixty miles west of Shanghai and in easy reach of international and domestic airports. Suzhou is an ancient city known as the Venice of China, famous for its canals and private gardens and home to scholars for more than two millenia.
文摘The conference will include eight oral sessions and one poster session.Many talks will be selected from the openly submittedabstracts on the basis of scientific merit and relevance.Social events throughout the conference provide ample opportunity forinformal interactions.Major topics on the conference include:neurogenesis,axon guidance,synapse formation,dendritemorphogenesis,developmental plasticity。
基金Supported by the Key Research and Development Project of Guangdong Province(No.2020B1111510001)the National Natural Science Foundation of China(No.U2244224)+1 种基金the PI Project of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2020GD0802)the Guangdong Special Support Team Program(No.2019BT02H594)。
文摘Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.
文摘Changes in isozymes of peroxidase, catalase, superoxide dismutase, polyphenol oxidase, and esterase and activities of per- oxidase and polyphenol oxidase in two annual Brassica varieties (AS-3 and CON, cold-tolerant and cold-sensitive, respectively) after 4℃ treatment were assayed. After the low temperature treatment, PAGE patterns of isozymes of peroxidase, catalase, superoxide dismutase, polyphenol oxidase, and esterase showed that the expressions and activities of these enzymes in the AS-3 variety were higher than the CON variety. Under normal and cold conditions, peroxidase and esterase activities of AS-3 were higher than those of CON. The relative freezing tolerance of these two cultivars was discussed.
基金under the auspices of National Natural Science Foundation of China (Grant No.40825015 and No.40810059006)
文摘To better understand the dust storm (hereafter DS) inducing circulation in the China-Mongolia (CM) DS activity area,the spring mean circulation features and differences on lower levels in three subregions of the CM DS area for the majorandminor-DS years have,as a whole (not partly),been analyzed,utilizing the National Centers for Environmental Prediction and the National Center for Atmospheric Research (NCEP/NCAR) reanalyzed gridded data,the observed DS frequency data in the CM area,and the composite analysis method.The main conclusions are as follows:(1) Judging from the differences in the DS-inducing systems,dust origins,paths of invading cold air,and main DS-strike areas,the whole CM DS area is roughly divided into the three subre-gions:the East-,Middleand West-CM subregions (in this paper,referred to as E-,M-,and W-CM).(2) In major DSs during spring over the E-CM,the middleand lower-level troughs or cyclones over the Japan Sea and northeastern China (NEC) domi-nate.The invading cold air along the northeastern (NE) or north by east (NE) path often causes the DS in the E-CM region.But nearly the opposite is true inminor DS during spring in E-CM.(3) In the major DS during spring over the M-CM region,the Mongolian troughs or cyclones are the main DS-inducing systems.The strong invading cold air along the northwestern (NW)or north by west (Nw) path causes the DSs in the M-CM region.(4) In the major DSs during spring over the W-CM region,the South Xinjiang heat lows prevail,the intruding cold air has a western path,and creates the DSs in South Xinjiang.(5) In the past 50 years,the DSs over the M-CM region have had the most severe impact on the preceding three subregions of the CM DS area.Overall,DS activities over all of three regions of the CM area decreased in the past (particularly,over Mand W-CM regions since the mid-1980s.But there existed a short and sudden increasing in E-CM in the years 2000-2002.(6) It is circulation changes and desertification evolutions that cause the yearly and decadal changes of DS in CM area,especially the former.With the backdrop of global warming in the future,perhaps the decreased DS activities over Mand W-CM will persist for some time again,and special attention should be paid to ones over E-CM or to the individual DS events over Mand W-CM.
基金Supported by the Guangdong Province Marine Economic Development(Six Major Marine Industries)Special Fund Project(No.[2021]No.58)the National Key R&D Program of China(No.2018YFC0310000)the National Natural Science Foundation of China(Nos.41776056,42076054)。
文摘Cold seeps spread worldwide along the continental margins,which are closely related to the exploration of gas hydrates.Cold-seep carbonates have been reported to record the nature of seepage,including fluid source,sedimentary environment,and variation of seepage activity.We investigated the morphology,mineralogy,element compositions,and carbon and oxygen isotopes of 15 cold-seep carbonates collected from the Shenhu area,and compared them with 2 carbonates from the Haima cold seep,the South China Sea(SCS),to promote our knowledge of cold-seep system in SCS.Most of the Shenhu carbonates exhibit crust morphology,and some are in the form of chimneys and blocks.Their absolute(20%–65%)and relative carbonate mineral contents(mainly aragonite and calcite,with minor samples containing dolomite)vary significantly,indicating the multi-stage methane leakage in our study area.Some samples show a slight negative Ce anomaly,suggesting either the mixing of seawater or variation of the redox condition during the precipitation;the cooccurrence of strongly enriched U and Mo demonstrates anoxic condition during precipitation.The mixed genetic methane source was interpreted by δ^(13)C of the Shenhu carbonates to range from-22.34‰to-59.30‰Vienna PeeDee Belemnite(VPDB),and the slight ^(18)O-enrichment imprinted on the carbonates suggests the possible influence from hydrate dissociation.The Haima carbonates,with biogenic methane as the main gas source,were presumably formed in a stronger fluid flux by compared with our Shenhu samples.
基金Korea Institute for Advancement of Technology(KIAT)grant funded by the Korea Government(MOTIE)(P0012724,The Competency Development Program for Industry Specialist)and the Soonchunhyang University Research Fund.
文摘Electrocardiogram(ECG)electrodes are conductive pads applied to the skin to measure cardiac activity.Ag/AgCl electrodes are the commercial product which widely used to obtain ECGs.When monitoring the ECG in a hot spring,Ag/AgCl electrodes must be waterproofed;however,this is time-consuming,and the adhesive may tear the skin on removal.For solving the problem,we developed the carbon pencil lead(CPL)electrodes for use in hot springs.Both CPL and Ag/AgCl electrodes were connected to ECG100C’s cables.The Performance was evaluated in three conditions as following:hot spring water with and without bubble,and in cold water.In each environment,the procedure was followed by three different protocols that are recording from the dry condition,hot spring water immersion with and without movement,post hot spring water condition.Under dry and wet conditions,both electrodes can obtain the waveform of the ECG signal in which all PQRST waves were identifiable.Nevertheless,the signal quality of both types of electrodes was different in water immersion with and without movement.The overall morphology obtained by Ag/AgCl electrodes was unstable higher than that of CPL electrodes in immersion without movement condition.The CPL electrodes provided better ECG waveform quality compared to Ag/AgCl electrodes in which the ECG signal had high waveforms distortion in water immersion with movement condition.