d and As both have harmful effects on the growth,development and seed germination of alfalfa, especially in such a condition as the coexistence of Cd and As in soil environment The research using the pot-culture imita...d and As both have harmful effects on the growth,development and seed germination of alfalfa, especially in such a condition as the coexistence of Cd and As in soil environment The research using the pot-culture imitative method first found that if soil was simultaneously polluted by Cd and As,function of alfalfa absorbing Cd from soil may be promoted because of the existence of As,in conversely,Cd may inhibit alfalfa plant from absorbing As It was also found that secon- dary ecological effects were most likely to be brought out due to the coexistence of Cd and As. For example,alfalfa is passive to excessively absorb Cu and Pb .The harmful effects undoubtedly intensi- fy the contamination of alfalfa, The results showed that the mechanism of the interaction among Cd,As,Pb and Cu in soil-alfalfa ecosystems is very complicated.展开更多
The magnetocaloric effect(MCE) of RT Si and RT Al systems with R = Gd–Tm, T = Fe–Cu and Pd, which have been widely investigated in recent years, is reviewed. It is found that these RT X compounds exhibit various c...The magnetocaloric effect(MCE) of RT Si and RT Al systems with R = Gd–Tm, T = Fe–Cu and Pd, which have been widely investigated in recent years, is reviewed. It is found that these RT X compounds exhibit various crystal structures and magnetic properties, which then result in different MCE. Large MCE has been observed not only in the typical ferromagnetic materials but also in the antiferromagnetic materials. The magnetic properties have been studied in detail to discuss the physical mechanism of large MCE in RT X compounds. Particularly, some RT X compounds such as Er Fe Si,Ho Cu Si, Ho Cu Al exhibit large reversible MCE under low magnetic field change, which suggests that these compounds could be promising materials for magnetic refrigeration in a low temperature range.展开更多
Neurodegenerative diseases affect millions of individuals worldwide.It has been estimated that the number of patients affected by neurodegenerative diseases such as Alzheimer’s disease(AD),Parkinson’s disease(PD...Neurodegenerative diseases affect millions of individuals worldwide.It has been estimated that the number of patients affected by neurodegenerative diseases such as Alzheimer’s disease(AD),Parkinson’s disease(PD),Huntington’s disease(HD),展开更多
Atrial fibrillation (AF) is a kind of common arrhythmia, which, besides affecting cardiac function, has another serious outcome, that is, it is easy to form atrial thrombosis and induce thrombus/embolus, especially ce...Atrial fibrillation (AF) is a kind of common arrhythmia, which, besides affecting cardiac function, has another serious outcome, that is, it is easy to form atrial thrombosis and induce thrombus/embolus, especially cerebral embolus. The incidence of left atrial thrombosis ( LAT) could reach 25% - 30%(1) , the incidence of embol-展开更多
The magnetocaloric effect(MCE) in EuCu1.75P2 compound is studied by the magnetization and heat capacity measurements.Magnetization and modified Arrott plots indicate that the compound undergoes a second-order phase ...The magnetocaloric effect(MCE) in EuCu1.75P2 compound is studied by the magnetization and heat capacity measurements.Magnetization and modified Arrott plots indicate that the compound undergoes a second-order phase transition at TC ~ 51 K.A large reversible MCE is observed around TC.The values of maximum magnetic entropy change(-△SxMma) reach 5.6 J·kg^-1·K-1 and 13.3 J·kg^-1·K-1 for the field change of 2 T and 7 T,respectively,with no obvious hysteresis loss in the vicinity of Curie temperature.The corresponding maximum adiabatic temperature changes(△Tadmax) are evaluated to be 2.1 K and 5.0 K.The magnetic transition and the origin of large MCE in EuCu1.75P2 are also discussed.展开更多
Antiperovskite compounds Mn3Ag1-xCoxN (x =0.2, 0.5 and 0.8) are synthesized and the doping effect of the magnetic element Co at the Ag site is investigated. The crystal structure is not changed by the introduction o...Antiperovskite compounds Mn3Ag1-xCoxN (x =0.2, 0.5 and 0.8) are synthesized and the doping effect of the magnetic element Co at the Ag site is investigated. The crystal structure is not changed by the introduction of Co. However, with the increase of the content of Co, the spin reorientation gradually disappears and the antiferromagnetic transition changes to the ferromagnetic transition at the elevated temperature when x = 0.8. In addition, all of the magnetic phase transitions at the elevated temperature are always accompanied by the abnormal thermal expansion behaviors and an entropy change. Moreover, when x = 0.8, the coefficient of linear expansion is -1.89 × 10^-6 K^-1 (290-310K, △T =20 K), which is generally considered as the low thermal expansion.展开更多
The effect of the Chinese herbal compound (CHC) on solid sarcoma 180 (S180) in Swiss mice was studied either alone or in combination with 5-fluorouracil (5FU), cyclophosphamide (CYT) or mitomycin C (MMC). The prelimin...The effect of the Chinese herbal compound (CHC) on solid sarcoma 180 (S180) in Swiss mice was studied either alone or in combination with 5-fluorouracil (5FU), cyclophosphamide (CYT) or mitomycin C (MMC). The preliminary results indicated that combination treatment seemed to possess better antitumor activity than chemotherapy alone. The treatment with CHC alone however had neither an obvious antitumor effect in tumor bearing mice nor toxicity in normal mice. These results show that CHC may stimulate organs of the immune system such as the spleen to be im-munomodulators and enhance the antitumor activity of some chemotherapeutic agents.展开更多
A series of CeMn2(Si1-xGex)2(x = 0.2, 0.4, 0.6, 0.8) compounds are prepared by the arc-melting method. All the samples primarily crystallize in the Th Cr2Si2-type structure. The temperature dependences of zero-fie...A series of CeMn2(Si1-xGex)2(x = 0.2, 0.4, 0.6, 0.8) compounds are prepared by the arc-melting method. All the samples primarily crystallize in the Th Cr2Si2-type structure. The temperature dependences of zero-field-cooled(ZFC) and FC magnetization measurements show a transition from antiferromagnetic(AFM) state to ferromagnetic(FM) state at room temperature with the increase of the Ge concentration. For x = 0.4, the sample exhibits two kinds of phase transitions with increasing temperature: from AFM to FM and from FM to paramagnetic(PM) at around TN-197 K and T C-300 K,respectively. The corresponding Arrott curves indicate that the AFM–FM transition is of first-order character and the FM–PM transition is of second-order character. Meanwhile, the coexistence of positive and negative magnetic entropy changes can be observed, which are corresponding to the AFM–FM and FM–PM transitions, respectively.展开更多
90-09 is a cmpound made with GA3,4PU-30and some trace elements(B ete.).To studythe effects of 90-09 on the leaf senescence ofhybrid rice leaf,the changes of activities ofsome degradation enzyme and the contents ofendo...90-09 is a cmpound made with GA3,4PU-30and some trace elements(B ete.).To studythe effects of 90-09 on the leaf senescence ofhybrid rice leaf,the changes of activities ofsome degradation enzyme and the contents ofendogenous hormones(ABA,ZRs,GAs,andIAA),protein,and nucleic acids were mea-sured during leaf senescence. Shanyou 63,an indica hybrid rice,wasused in this experiment.Rice plants were firstsprayed with 90-09(115 ml/hm~2) solution 10d after heading,followed by two more sprayswith once a week.The controlled plants weresprayed with water only.展开更多
In recent decades,Southwest China(SWC)has suffered from frequent super droughts,leading to severe economic losses and ecological degradation.This study investigates the characteristics of super droughts in SWC during ...In recent decades,Southwest China(SWC)has suffered from frequent super droughts,leading to severe economic losses and ecological degradation.This study investigates the characteristics of super droughts in SWC during 1961-2022,reveals the compounding effect of multiscalar anomalies,and explores the plausible atmospheric circulation mechanisms responsible.The nature of super drought is a compound drought caused by the superposition of extreme drought events across multiple time scales.By contrasting the typical drought cases in 2006 and 2022,the decisive role of multiscalar drought compounding is confirmed.Based on the Comprehensive Multiscalar Index(CMI),multiple super drought events in SWC were identified to be temporally clustered during 2006-2014.Among them,the decadal background of enhanced evaporation and precipitation deficit at long time scales is a necessary condition for shaping the overall pattern of super droughts,while the precipitation and evaporation anomalies at short time scales trigger the outbreak of super droughts,determining the exact timing of occurrence.These events include August-September 2006,November 2009 to May 2010,July-October 2011,April-May 2012,January-April 2013,etc.Statistical results suggest that the contribution of superposed precipitation anomalies to super drought is 2.4 times that of evaporation.As regards the circulation mechanisms affecting multiscalar precipitation,the anomalous spatial patterns at short-term and long-term scales are similar,featuring the cyclonic circulation over the South China Sea and the northeasterly wind anomalies together with the subsidence center over SWC.During 2006-2014,the possible causes for the cross-seasonal persistent precipitation reduction in SWC are the extreme negative phase of the Pacific Decadal Oscillation(PDO)in the North Pacific as well as the pronounced warming of the warm pool in the western Pacific.The key dynamic processes are outlined as follows.On the one hand,the negative PDO phase generates anomalous anticyclonic circulation in the North Pacific,with the northeasterly winds on its southwest flank extending to Southeast Asia,hindering moisture transport into SWC.On the other hand,the warming of the warm pool excites anomalous cyclonic circulation to its northwest,also giving rise to northeasterly wind anomalies over SWC.Meanwhile,the ascending motion over the warm pool region diverges at upper levels with outflows converging aloft over SWC,which further induces compensating downward motion there.The combined effect of the above two remote forcings establishes a climatic background state unfavorable for precipitation over SWC at long time scales,thus constituting a crucial prerequisite for the superimposition of short-term precipitation anomalies to develop into super droughts.展开更多
OBJECTIVE To investigate the cerebralvasorelaxant material basis of Xiaoxuming decoction.METHODS According to the Xiaoxuming decoction herb sources,we retrieved the chemical structure from the literatures and the Chin...OBJECTIVE To investigate the cerebralvasorelaxant material basis of Xiaoxuming decoction.METHODS According to the Xiaoxuming decoction herb sources,we retrieved the chemical structure from the literatures and the Chinese Natural Product Database(http://pharmdata.ncmi.cn).By using microvessel tension system,we checked the vasorelaxanteffects of Xiaoxuming decoction anti-cerebral ischemia effective components group(XXMDECG)and the available composition compounds on pre-contracted basilar artery ring.RESULTS963 compoundsin the decoction,including 81Fangfeng,77 Mahuang,130 Shengjiang,31 Guizhi,91 Huangqin,127 Renshen,73 Chuanxiong,44 Shaoyao,39 Xingren,42 Fangji,62 Fuzi and 166 Gancao were collected.The five largest number classes of compounds in the decoction are volatile oil(32%),flavone(32%),alkaloid(13%),saponin(7%),polyphenol and organic acid(5%).XXMDECG at concentration from 1 to 400μg·mL-1can dilate the KCl(60 mmol·L-1)and ET-1(0.01μmol·L-1)pre-contracted rat basilar artery rings in a dose-dependent manner.There are 6 compounds with vasorelaxant ratio more than 50%at the concentration of 10μmol·L-1.CONCLUSION Xiaoxuming decoction contains abundant chemical structure.It has the material basis of multiple ingredients and multiple targets.The XXMDECG are able to dilate the rat basilar artery rings in a dose-dependent manner.The network interactions between varies of chemical compounds in Xiaoxuming decoction and the vasoconstriction associated targets result in the comprehensive regulation mechanisms of vascular function.展开更多
The structures, the martensitic transformations, and the magnetic properties are studied systematically in Mn50Ni40-xCuxIn10, Mn50-xCuxNi40In10, and Mn50Ni40In10-xCux alloys. The partial substitution of Ni by Cu reduc...The structures, the martensitic transformations, and the magnetic properties are studied systematically in Mn50Ni40-xCuxIn10, Mn50-xCuxNi40In10, and Mn50Ni40In10-xCux alloys. The partial substitution of Ni by Cu reduces the martensitic transformation temperature, but has little influence on the Curie temperature of austenite. Comparatively, the martensitic transformation temperature increases and the Curie temperature of austenite decreases with the partial replacement of Mn or In by Cu. The magnetization difference between the austenite phase and the martensite phase reaches 70 emu/g in Mn50Ni39Cu1In10; a field-induced martensite-to-austenite transition is observed in this alloy.展开更多
With the knowledge on the significant effect of basic site and Ru on the catalytic performance of heterogeneous catalysts in the isomerization of linoleic acid to conjugated linoleic acid,a series of Ru-Mg Alx compoun...With the knowledge on the significant effect of basic site and Ru on the catalytic performance of heterogeneous catalysts in the isomerization of linoleic acid to conjugated linoleic acid,a series of Ru-Mg Alx compounds with different basicity have been prepared by controlling the Mg/Al molar ratio. The results showed the catalysts with different basicity markedly influence the structure,the Ru dispersion,properties and catalytic performances for the isomerization reaction. The strong basic site is conductive to the high yield of CLA products. The strong basic site and the well-dispersion RuO2synergetic catalysis for the isomerization reaction,basic site and the well-dispersion RuO2synergetic effect are possibly via a Mg-O-Ru linkage.展开更多
Understanding the functional effects of genetic variants is crucial in modern genomics and genetics. Transcription factor binding sites (TFBSs) are one of the most important cis-regulatory elements. While multiple t...Understanding the functional effects of genetic variants is crucial in modern genomics and genetics. Transcription factor binding sites (TFBSs) are one of the most important cis-regulatory elements. While multiple tools have been developed to assess functional effects of genetic variants at TFBSs, they usually assume that each variant works in isolation and neglect the potential "interference" among multiple variants within the same TFBS. In this study, we presented COPE-TFBS (Context-Oriented Predictor for variant Effect on Transcription Factor Binding Site), a novel method that considers sequence context to accurately predict variant effects on TFBSs. We systematically re-analyzed the sequencing data from both the 1000 Genomes Project and the Genotype-Tissue Expression (GTEx) Project via COPE-TFBS, and identified numbers of novel TFBSs, transformed TFBSs and discordantly annotated TFBSs resulting from multiple variants, further highlighting the necessity of sequence context in accurately annotating genetic variants.展开更多
Production and characteristics of typical taste and odor (T&O) compounds by Microcystis aeruginosa were investigated. A few terpenoid chemicals, including 2-MIB, β-cyclocitral, and β-ionone, and a few sulfur comp...Production and characteristics of typical taste and odor (T&O) compounds by Microcystis aeruginosa were investigated. A few terpenoid chemicals, including 2-MIB, β-cyclocitral, and β-ionone, and a few sulfur compounds, such as dimethyl sulfide and dimethyl trisulfide, were detected. β-Cyclocitral and β-carotene concentrations were observed to be relevant to the growth phases of Microcystis. During the stable growth phase, 41-865 fg/cell of β-cyclocitral were found in the laboratory culture. β-Cyclocitral concentrations correlated closely with β-carotene concentrations, with the correlation coefficient R2 = 0.96, as it is formed from the cleavage reaction of β-carotene. For dead cell cases, a high concentration of dimethyl trisulfide was detected at 3.48-6.37 fg/cell. Four T&O compounds, including β-cyclocitral, β-ionone, heptanal and dimethyl trisulfide, were tested and found to be able to inhibit and damage Microcystis cells to varying degrees. Among these chemicals, β-cyclocitral has the strongest ability to quickly rupture cells.展开更多
Eighteen carbonyl species in C_1-C_(10) were measured in the dining areas,kitchens and exhaust streams of six different restaurant types in Kaohsiung,southern Taiwan.Measured results in the dining areas show that Ja...Eighteen carbonyl species in C_1-C_(10) were measured in the dining areas,kitchens and exhaust streams of six different restaurant types in Kaohsiung,southern Taiwan.Measured results in the dining areas show that Japanese barbecue(45.06 ppb) had the highest total carbonyl concentrations(sum of 18 compounds),followed by Chinese hotpot(38.21 ppb),Chinese stir-frying(8.99 ppb),Western fast-food(8.22 ppb),Chinese-Western mixed style(7.38 ppb),and Chinese buffet(3.08 ppb),due to their different arrangements for dining and cooking spaces and different cooking methods.On average,low carbon-containing species(C_1-C_4),e.g.,formaldehyde,acetaldehyde,acetone and butyraldehyde were dominant and contributed 55.01%-94.52%of total carbonyls in the dining areas of all restaurants.Meanwhile,Chinese-Western mixed restaurants(45.48 ppb) had high total carbonyl concentrations in kitchens mainly because of its small kitchen and poor ventilation.However,high carbon-containing species(C_5-C_(10)) such as hexaldehyde,heptaldehyde and nonanaldehyde(16.62%-77.00%of total carbonyls) contributed comparatively with low carbon-containing compounds(23.01%-83.39%of total carbonyls) in kitchens.Furthermore,Chinese stir-frying(132.10 ppb),Japanese barbecue(125.62 ppb),Western fast-food(122.67 ppb),and Chinese buffet(119.96 ppb) were the four restaurant types with the highest total carbonyl concentrations in exhaust streams,indicating that stir-frying and grilling are inclined to produce polluted gases.Health risk assessments indicate that Chinese hotpot and Japanese barbecue exceeded the limits of cancer risk(10^(-6)) and hazard index(=1),mainly due to high concentrations of formaldehyde.The other four restaurants were below both limits.展开更多
Green leaf volatiles(GLVs) emitted by plants after stress or damage induction are a major part of biogenic volatile organic compounds(BVOCs). Proton transfer reaction time-of-flight mass spectrometry(PTR-TOF-MS)...Green leaf volatiles(GLVs) emitted by plants after stress or damage induction are a major part of biogenic volatile organic compounds(BVOCs). Proton transfer reaction time-of-flight mass spectrometry(PTR-TOF-MS) is a high-resolution and sensitive technique for in situ GLV analyses, while its performance is dramatically influenced by humidity, electric field,etc. In this study the influence of gas humidity and the effect of reduced field(E/N) were examined in addition to measuring calibration curves for the GLVs. Calibration curves measured for seven of the GLVs in dry air were linear, with sensitivities ranging from 5 to10 ncps/ppbv(normalized counts per second/parts per billion by volume). The sensitivities for most GLV analyses were found to increase by between 20% and 35% when the humidity of the sample gas was raised from 0% to 70% relative humidity(RH) at 21°C, with the exception of(E)-2-hexenol. Product ion branching ratios were also affected by humidity,with the relative abundance of the protonated molecular ions and higher mass fragment ions increasing with humidity. The effect of reduced field(E/N) on the fragmentation of GLVs was examined in the drift tube of the PTR-TOF-MS. The structurally similar GLVs are acutely susceptible to fragmentation following ionization and the fragmentation patterns are highly dependent on E/N. Overall the measured fragmentation patterns contain sufficient information to permit at least partial separation and identification of the isomeric GLVs by looking at differences in their fragmentation patterns at high and low E/N.展开更多
文摘d and As both have harmful effects on the growth,development and seed germination of alfalfa, especially in such a condition as the coexistence of Cd and As in soil environment The research using the pot-culture imitative method first found that if soil was simultaneously polluted by Cd and As,function of alfalfa absorbing Cd from soil may be promoted because of the existence of As,in conversely,Cd may inhibit alfalfa plant from absorbing As It was also found that secon- dary ecological effects were most likely to be brought out due to the coexistence of Cd and As. For example,alfalfa is passive to excessively absorb Cu and Pb .The harmful effects undoubtedly intensi- fy the contamination of alfalfa, The results showed that the mechanism of the interaction among Cd,As,Pb and Cu in soil-alfalfa ecosystems is very complicated.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.5137102611274357+1 种基金and 51327806)the Fundamental Research Funds for the Central Universities(Grant Nos.FRF-TP-14-011A2 and FRF-TP-15-002A3)
文摘The magnetocaloric effect(MCE) of RT Si and RT Al systems with R = Gd–Tm, T = Fe–Cu and Pd, which have been widely investigated in recent years, is reviewed. It is found that these RT X compounds exhibit various crystal structures and magnetic properties, which then result in different MCE. Large MCE has been observed not only in the typical ferromagnetic materials but also in the antiferromagnetic materials. The magnetic properties have been studied in detail to discuss the physical mechanism of large MCE in RT X compounds. Particularly, some RT X compounds such as Er Fe Si,Ho Cu Si, Ho Cu Al exhibit large reversible MCE under low magnetic field change, which suggests that these compounds could be promising materials for magnetic refrigeration in a low temperature range.
文摘Neurodegenerative diseases affect millions of individuals worldwide.It has been estimated that the number of patients affected by neurodegenerative diseases such as Alzheimer’s disease(AD),Parkinson’s disease(PD),Huntington’s disease(HD),
基金This project is supported by Guangdong Provincial Ad-ministration of TCM(No.99592)
文摘Atrial fibrillation (AF) is a kind of common arrhythmia, which, besides affecting cardiac function, has another serious outcome, that is, it is easy to form atrial thrombosis and induce thrombus/embolus, especially cerebral embolus. The incidence of left atrial thrombosis ( LAT) could reach 25% - 30%(1) , the incidence of embol-
基金Project supported by the National Natural Science Foundation of China (Grant No. 11004044)the Natural Science Foundation of Zhejiang Province,China(Grant No. Y4110581)
文摘The magnetocaloric effect(MCE) in EuCu1.75P2 compound is studied by the magnetization and heat capacity measurements.Magnetization and modified Arrott plots indicate that the compound undergoes a second-order phase transition at TC ~ 51 K.A large reversible MCE is observed around TC.The values of maximum magnetic entropy change(-△SxMma) reach 5.6 J·kg^-1·K-1 and 13.3 J·kg^-1·K-1 for the field change of 2 T and 7 T,respectively,with no obvious hysteresis loss in the vicinity of Curie temperature.The corresponding maximum adiabatic temperature changes(△Tadmax) are evaluated to be 2.1 K and 5.0 K.The magnetic transition and the origin of large MCE in EuCu1.75P2 are also discussed.
基金Supported by the National Natural Science Foundation of China under Grant No 51172012the Fundamental Research Funds for the Central Universities
文摘Antiperovskite compounds Mn3Ag1-xCoxN (x =0.2, 0.5 and 0.8) are synthesized and the doping effect of the magnetic element Co at the Ag site is investigated. The crystal structure is not changed by the introduction of Co. However, with the increase of the content of Co, the spin reorientation gradually disappears and the antiferromagnetic transition changes to the ferromagnetic transition at the elevated temperature when x = 0.8. In addition, all of the magnetic phase transitions at the elevated temperature are always accompanied by the abnormal thermal expansion behaviors and an entropy change. Moreover, when x = 0.8, the coefficient of linear expansion is -1.89 × 10^-6 K^-1 (290-310K, △T =20 K), which is generally considered as the low thermal expansion.
文摘The effect of the Chinese herbal compound (CHC) on solid sarcoma 180 (S180) in Swiss mice was studied either alone or in combination with 5-fluorouracil (5FU), cyclophosphamide (CYT) or mitomycin C (MMC). The preliminary results indicated that combination treatment seemed to possess better antitumor activity than chemotherapy alone. The treatment with CHC alone however had neither an obvious antitumor effect in tumor bearing mice nor toxicity in normal mice. These results show that CHC may stimulate organs of the immune system such as the spleen to be im-munomodulators and enhance the antitumor activity of some chemotherapeutic agents.
基金Project supported by the Beijing Natural Science Foundation,China(Grant No.2152034)the National Natural Science Foundation of China(Grant Nos.11274357 and 51271196)
文摘A series of CeMn2(Si1-xGex)2(x = 0.2, 0.4, 0.6, 0.8) compounds are prepared by the arc-melting method. All the samples primarily crystallize in the Th Cr2Si2-type structure. The temperature dependences of zero-field-cooled(ZFC) and FC magnetization measurements show a transition from antiferromagnetic(AFM) state to ferromagnetic(FM) state at room temperature with the increase of the Ge concentration. For x = 0.4, the sample exhibits two kinds of phase transitions with increasing temperature: from AFM to FM and from FM to paramagnetic(PM) at around TN-197 K and T C-300 K,respectively. The corresponding Arrott curves indicate that the AFM–FM transition is of first-order character and the FM–PM transition is of second-order character. Meanwhile, the coexistence of positive and negative magnetic entropy changes can be observed, which are corresponding to the AFM–FM and FM–PM transitions, respectively.
文摘90-09 is a cmpound made with GA3,4PU-30and some trace elements(B ete.).To studythe effects of 90-09 on the leaf senescence ofhybrid rice leaf,the changes of activities ofsome degradation enzyme and the contents ofendogenous hormones(ABA,ZRs,GAs,andIAA),protein,and nucleic acids were mea-sured during leaf senescence. Shanyou 63,an indica hybrid rice,wasused in this experiment.Rice plants were firstsprayed with 90-09(115 ml/hm~2) solution 10d after heading,followed by two more sprayswith once a week.The controlled plants weresprayed with water only.
基金supported by the National Natural Science Foundation of China(Grant Nos.42175041&42230605)the International Partnership Program of Chinese Academy of Sciences for Future Network(Grant No.060GJHZ2022104FN)+1 种基金the Youth Program of the Institute of Atmospheric Physics,Chinese Academy of Sciences during the 14th Five-Year Plan Periodthe Open Research Fund of Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province(Grant No.SZKT202204)。
文摘In recent decades,Southwest China(SWC)has suffered from frequent super droughts,leading to severe economic losses and ecological degradation.This study investigates the characteristics of super droughts in SWC during 1961-2022,reveals the compounding effect of multiscalar anomalies,and explores the plausible atmospheric circulation mechanisms responsible.The nature of super drought is a compound drought caused by the superposition of extreme drought events across multiple time scales.By contrasting the typical drought cases in 2006 and 2022,the decisive role of multiscalar drought compounding is confirmed.Based on the Comprehensive Multiscalar Index(CMI),multiple super drought events in SWC were identified to be temporally clustered during 2006-2014.Among them,the decadal background of enhanced evaporation and precipitation deficit at long time scales is a necessary condition for shaping the overall pattern of super droughts,while the precipitation and evaporation anomalies at short time scales trigger the outbreak of super droughts,determining the exact timing of occurrence.These events include August-September 2006,November 2009 to May 2010,July-October 2011,April-May 2012,January-April 2013,etc.Statistical results suggest that the contribution of superposed precipitation anomalies to super drought is 2.4 times that of evaporation.As regards the circulation mechanisms affecting multiscalar precipitation,the anomalous spatial patterns at short-term and long-term scales are similar,featuring the cyclonic circulation over the South China Sea and the northeasterly wind anomalies together with the subsidence center over SWC.During 2006-2014,the possible causes for the cross-seasonal persistent precipitation reduction in SWC are the extreme negative phase of the Pacific Decadal Oscillation(PDO)in the North Pacific as well as the pronounced warming of the warm pool in the western Pacific.The key dynamic processes are outlined as follows.On the one hand,the negative PDO phase generates anomalous anticyclonic circulation in the North Pacific,with the northeasterly winds on its southwest flank extending to Southeast Asia,hindering moisture transport into SWC.On the other hand,the warming of the warm pool excites anomalous cyclonic circulation to its northwest,also giving rise to northeasterly wind anomalies over SWC.Meanwhile,the ascending motion over the warm pool region diverges at upper levels with outflows converging aloft over SWC,which further induces compensating downward motion there.The combined effect of the above two remote forcings establishes a climatic background state unfavorable for precipitation over SWC at long time scales,thus constituting a crucial prerequisite for the superimposition of short-term precipitation anomalies to develop into super droughts.
基金The project supported by Major Scientific and Technological Special Project for "Significant New Drug Creation"(2013ZX09508104,2013ZX09402203)by Central Public Scientific Research Institution Fundamental Project(2014CX05)
文摘OBJECTIVE To investigate the cerebralvasorelaxant material basis of Xiaoxuming decoction.METHODS According to the Xiaoxuming decoction herb sources,we retrieved the chemical structure from the literatures and the Chinese Natural Product Database(http://pharmdata.ncmi.cn).By using microvessel tension system,we checked the vasorelaxanteffects of Xiaoxuming decoction anti-cerebral ischemia effective components group(XXMDECG)and the available composition compounds on pre-contracted basilar artery ring.RESULTS963 compoundsin the decoction,including 81Fangfeng,77 Mahuang,130 Shengjiang,31 Guizhi,91 Huangqin,127 Renshen,73 Chuanxiong,44 Shaoyao,39 Xingren,42 Fangji,62 Fuzi and 166 Gancao were collected.The five largest number classes of compounds in the decoction are volatile oil(32%),flavone(32%),alkaloid(13%),saponin(7%),polyphenol and organic acid(5%).XXMDECG at concentration from 1 to 400μg·mL-1can dilate the KCl(60 mmol·L-1)and ET-1(0.01μmol·L-1)pre-contracted rat basilar artery rings in a dose-dependent manner.There are 6 compounds with vasorelaxant ratio more than 50%at the concentration of 10μmol·L-1.CONCLUSION Xiaoxuming decoction contains abundant chemical structure.It has the material basis of multiple ingredients and multiple targets.The XXMDECG are able to dilate the rat basilar artery rings in a dose-dependent manner.The network interactions between varies of chemical compounds in Xiaoxuming decoction and the vasoconstriction associated targets result in the comprehensive regulation mechanisms of vascular function.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51001010 and 11174030)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20100006120001)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry of China
文摘The structures, the martensitic transformations, and the magnetic properties are studied systematically in Mn50Ni40-xCuxIn10, Mn50-xCuxNi40In10, and Mn50Ni40In10-xCux alloys. The partial substitution of Ni by Cu reduces the martensitic transformation temperature, but has little influence on the Curie temperature of austenite. Comparatively, the martensitic transformation temperature increases and the Curie temperature of austenite decreases with the partial replacement of Mn or In by Cu. The magnetization difference between the austenite phase and the martensite phase reaches 70 emu/g in Mn50Ni39Cu1In10; a field-induced martensite-to-austenite transition is observed in this alloy.
基金financially supported by the Natural Science Foundation of Fujian Province(No.2014J01032)
文摘With the knowledge on the significant effect of basic site and Ru on the catalytic performance of heterogeneous catalysts in the isomerization of linoleic acid to conjugated linoleic acid,a series of Ru-Mg Alx compounds with different basicity have been prepared by controlling the Mg/Al molar ratio. The results showed the catalysts with different basicity markedly influence the structure,the Ru dispersion,properties and catalytic performances for the isomerization reaction. The strong basic site is conductive to the high yield of CLA products. The strong basic site and the well-dispersion RuO2synergetic catalysis for the isomerization reaction,basic site and the well-dispersion RuO2synergetic effect are possibly via a Mg-O-Ru linkage.
基金supported by funds from the National Key R&D Program of China (2016YFC0901603)the China 863 Program (2015AA020108)+1 种基金the State Key Laboratory of Protein and Plant Gene Researchsupported in part by the National Program for Support of Top-notch Young Professionals
文摘Understanding the functional effects of genetic variants is crucial in modern genomics and genetics. Transcription factor binding sites (TFBSs) are one of the most important cis-regulatory elements. While multiple tools have been developed to assess functional effects of genetic variants at TFBSs, they usually assume that each variant works in isolation and neglect the potential "interference" among multiple variants within the same TFBS. In this study, we presented COPE-TFBS (Context-Oriented Predictor for variant Effect on Transcription Factor Binding Site), a novel method that considers sequence context to accurately predict variant effects on TFBSs. We systematically re-analyzed the sequencing data from both the 1000 Genomes Project and the Genotype-Tissue Expression (GTEx) Project via COPE-TFBS, and identified numbers of novel TFBSs, transformed TFBSs and discordantly annotated TFBSs resulting from multiple variants, further highlighting the necessity of sequence context in accurately annotating genetic variants.
基金supported by the National Natural Science Foundation of China (No.51208456)the Foundation of Key Laboratory of Yangtze River Water Environment, Ministry of Education (Tongji University), China (No.YRWEF201302)+1 种基金the National Major Science and Technology Project of China (No.2008ZX07421-002)the Taiwan National Science Council Project (No.NSC101-2221-E-006-152-MY3)
文摘Production and characteristics of typical taste and odor (T&O) compounds by Microcystis aeruginosa were investigated. A few terpenoid chemicals, including 2-MIB, β-cyclocitral, and β-ionone, and a few sulfur compounds, such as dimethyl sulfide and dimethyl trisulfide, were detected. β-Cyclocitral and β-carotene concentrations were observed to be relevant to the growth phases of Microcystis. During the stable growth phase, 41-865 fg/cell of β-cyclocitral were found in the laboratory culture. β-Cyclocitral concentrations correlated closely with β-carotene concentrations, with the correlation coefficient R2 = 0.96, as it is formed from the cleavage reaction of β-carotene. For dead cell cases, a high concentration of dimethyl trisulfide was detected at 3.48-6.37 fg/cell. Four T&O compounds, including β-cyclocitral, β-ionone, heptanal and dimethyl trisulfide, were tested and found to be able to inhibit and damage Microcystis cells to varying degrees. Among these chemicals, β-cyclocitral has the strongest ability to quickly rupture cells.
基金The "National" Science Council in Taiwan supported this work(No.NSC 101-2211-E-110-057)
文摘Eighteen carbonyl species in C_1-C_(10) were measured in the dining areas,kitchens and exhaust streams of six different restaurant types in Kaohsiung,southern Taiwan.Measured results in the dining areas show that Japanese barbecue(45.06 ppb) had the highest total carbonyl concentrations(sum of 18 compounds),followed by Chinese hotpot(38.21 ppb),Chinese stir-frying(8.99 ppb),Western fast-food(8.22 ppb),Chinese-Western mixed style(7.38 ppb),and Chinese buffet(3.08 ppb),due to their different arrangements for dining and cooking spaces and different cooking methods.On average,low carbon-containing species(C_1-C_4),e.g.,formaldehyde,acetaldehyde,acetone and butyraldehyde were dominant and contributed 55.01%-94.52%of total carbonyls in the dining areas of all restaurants.Meanwhile,Chinese-Western mixed restaurants(45.48 ppb) had high total carbonyl concentrations in kitchens mainly because of its small kitchen and poor ventilation.However,high carbon-containing species(C_5-C_(10)) such as hexaldehyde,heptaldehyde and nonanaldehyde(16.62%-77.00%of total carbonyls) contributed comparatively with low carbon-containing compounds(23.01%-83.39%of total carbonyls) in kitchens.Furthermore,Chinese stir-frying(132.10 ppb),Japanese barbecue(125.62 ppb),Western fast-food(122.67 ppb),and Chinese buffet(119.96 ppb) were the four restaurant types with the highest total carbonyl concentrations in exhaust streams,indicating that stir-frying and grilling are inclined to produce polluted gases.Health risk assessments indicate that Chinese hotpot and Japanese barbecue exceeded the limits of cancer risk(10^(-6)) and hazard index(=1),mainly due to high concentrations of formaldehyde.The other four restaurants were below both limits.
基金supported by the Chinese National Natural Science Foundation (41175110)the funding for the Distinguished Professor of Jiangsu Province
文摘Green leaf volatiles(GLVs) emitted by plants after stress or damage induction are a major part of biogenic volatile organic compounds(BVOCs). Proton transfer reaction time-of-flight mass spectrometry(PTR-TOF-MS) is a high-resolution and sensitive technique for in situ GLV analyses, while its performance is dramatically influenced by humidity, electric field,etc. In this study the influence of gas humidity and the effect of reduced field(E/N) were examined in addition to measuring calibration curves for the GLVs. Calibration curves measured for seven of the GLVs in dry air were linear, with sensitivities ranging from 5 to10 ncps/ppbv(normalized counts per second/parts per billion by volume). The sensitivities for most GLV analyses were found to increase by between 20% and 35% when the humidity of the sample gas was raised from 0% to 70% relative humidity(RH) at 21°C, with the exception of(E)-2-hexenol. Product ion branching ratios were also affected by humidity,with the relative abundance of the protonated molecular ions and higher mass fragment ions increasing with humidity. The effect of reduced field(E/N) on the fragmentation of GLVs was examined in the drift tube of the PTR-TOF-MS. The structurally similar GLVs are acutely susceptible to fragmentation following ionization and the fragmentation patterns are highly dependent on E/N. Overall the measured fragmentation patterns contain sufficient information to permit at least partial separation and identification of the isomeric GLVs by looking at differences in their fragmentation patterns at high and low E/N.