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Dynamics of nonstructural carbohydrates in seagrass Thalassia hemprichii and its response to shading 被引量:4
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作者 JIANG Zhijian HUANG Xiaoping ZHANG Jingping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第8期61-67,共7页
A field survey was performed to examine nonstructural carbohydrate (NSC) dynamics in seagrass Thalassia hemprichii at the Xincun Bay in southern China. An indoor experiment to investigate the response of NSC in T. h... A field survey was performed to examine nonstructural carbohydrate (NSC) dynamics in seagrass Thalassia hemprichii at the Xincun Bay in southern China. An indoor experiment to investigate the response of NSC in T. hemprichiito shade was conducted. Belowground tissue of T. hemprichiiwas the dominant site of NSC reserves, and soluble sugar was the primary storage compound. The starch content of belowground tissue was lower in high intertidal areas than in low intertidal areas, indicating that the longer air exposure in high intertidal areas resulted in less NSC synthesis and less accumulation of NSC in T. hemprichii. The lowest level of soluble sugar and its proportion to NSC in belowground tissue were observed near the cage culture area, where the nutrient concentration in water and sediment was the highest; while the highest level of that was observed near the coastal shrimp farm, where salinity was the lowest. Soluble sugar in belowground tis- sue showed the following trend: summer〉spring〉winter〉autumn. This corresponded to seasonal changes in the intensity of light. Leaf sugar accumulated during the autumn-winter period, providing a carbon and energy source for flower bud formation and seed germination. Short-term shading decreased NSC accumu- lation. Collectively, these results suggest that nutrient enrichment, freshwater discharge and exposure to air affect NSC dynamics in T. hemprichii. Light intensity, flower bud formation, and seed germination were all found to induce seasonal variations in NSC in T. hemprichii. 展开更多
关键词 Thalassia hemprichii nonstructural carbohydrates Xincun Bay DYNAMICS SHADE
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Divergent allocations of nonstructural carbohydrates shape growth response to rainfall reduction in two subtropical plantations 被引量:3
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作者 Xinwei Guo Shirong Liu +8 位作者 Hui Wang Zhicheng Chen Jinglei Zhang Lin Chen Xiuqing Nie Lu Zheng Daoxiong Cai Hongyan Jia Baoliang Niu 《Forest Ecosystems》 SCIE CSCD 2022年第2期222-233,共12页
Nonstructural carbohydrates(NSC)are indicators of tree carbon balance and play an important role in regulating plant growth and survival.However,our understanding of the mechanism underlying drought-induced response o... Nonstructural carbohydrates(NSC)are indicators of tree carbon balance and play an important role in regulating plant growth and survival.However,our understanding of the mechanism underlying drought-induced response of NSC reserves remains limited.Here,we conducted a long-term throughfall exclusion(TFE)experiment to investigate the seasonal responses of NSC reserves to manipulative drought in two contrasting tree species(a broadleaved tree Castanopsis hystrix Miq.and a coniferous tree Pinus massoniana Lamb.)of the subtropical China.We found that in the dry season,the two tree species differed in their responses of NSC reserves to TFE at either the whole-tree level or by organs,with significantly depleted total NSC reserves in roots in both species.Under the TFE treatment,there were significant increases in the NSC pools of leaves and branches in C.hystrix,which were accompanied by significant decreases in fine root biomass and radial growth without significant changes in canopy photosynthesis;while P.massoniana exhibited significant increase in fine root biomass without significant changes in radial growth.Our results suggested that under prolonged water limitation,NSC usage for growth in C.hystrix is somewhat impaired,such that the TFE treatment resulted in NSC accumulation in aboveground organs(leaf and branch);whereas P.massoniana is capable of efficiently utilizing NSC reserves to maintain its growth under drought conditions.Our findings revealed divergent NSC allocations under experimental drought between the two contrasting tree species,which are important for better understanding the differential impacts of climate change on varying forest trees and plantation types in subtropical China. 展开更多
关键词 PHOTOSYNTHESIS Carbon balance Tree growth nonstructural carbohydrates Carbon limitation
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Effects of pruning intensity on nonstructural carbohydrates of Populus alba×P.talassica in the arid desert region of Northwest China 被引量:3
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作者 Jun Zhang Liqing Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期823-830,共8页
Although pruning is important to obtain highquality,large-diameter timber,the effects of pruning on nonstructural carbohydrates(NSC)in aboveground organs of many timber species are not well understood.Three intensitie... Although pruning is important to obtain highquality,large-diameter timber,the effects of pruning on nonstructural carbohydrates(NSC)in aboveground organs of many timber species are not well understood.Three intensities of pruning(none,moderate and severe)were tested on poplars(Populus alba×P.talassica)in the arid desert region of northwest China to compare the concentrations of soluble sugar(SS),starch(ST)and total nonstructural carbohydrate(TNC)in leaves,branches and trunks during the growing season.The concentration of NSC components after different pruning intensities varied similarly in seasonal patterns,increasing slowly at the beginning of the growing season,continuously declining in the middle,then gradually recovering by the end of the growing season.The monthly mean NSC concentration in poplar differed significantly among the three pruning intensities(p<0.05).The SS concentration in pruned trees was higher than in unpruned trees(p<0.05).For moderately pruned trees,the concentrations of ST and TNC in trunks and branches were higher than in unpruned and in severely pruned trees(p<0.05).Compared with no pruning,pruning changed the seasonal variation in NSC concentration.The orders of SS and TNC concentrations in aboveground organs were leaf>branch>trunk,while the order of ST concentration was trunk>leaf>branch,which was related to functional differences of plant organs.The annual average growth in height of unpruned,moderately pruned,and severely pruned poplars was 0.21±0.06,0.45±0.09 and 0.24±0.05 m,respectively,and the annual average growth in DBH were 0.92±0.04,1.27±0.06 and 1.02±0.05 cm,respectively.Our results demonstrate that moderate pruning may effectively increase the annual growth in tree height and DBH while avoiding damage caused by excessive pruning to the tree body.Therefore,moderate pruning may increase the NSC storage and improve the growth of timber species. 展开更多
关键词 Pruning intensity nonstructural carbohydrate Populus alba×P.talassica Seasonal pattern
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Allocation patterns of nonstructural carbohydrates in response to CO_(2)elevation and nitrogen deposition in Cunninghamia lanceolata saplings 被引量:2
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作者 Wenhui Zheng Renshan Li +7 位作者 Qingpeng Yang Weidong Zhang Ke Huang Xin Guan Longchi Chen Xin Yu Qingkui Wang Silong Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期87-98,共12页
Stored nonstructural carbohydrates(NSC)indicate a balance between photosynthetic carbon(C)assimilation and growth investment or loss through respiration and root exudation.They play an important role in plant function... Stored nonstructural carbohydrates(NSC)indicate a balance between photosynthetic carbon(C)assimilation and growth investment or loss through respiration and root exudation.They play an important role in plant function and whole-plant level C cycling.CO_(2)elevation and nitrogen(N)deposition,which are two major environmental issues worldwide,aff ect plant photosynthetic C assimilation and C release in forest ecosystems.However,information regarding the eff ect of CO_(2)elevation and N deposition on NSC storage in diff erent organs remains limited,especially regarding the trade-off between growth and NSC reserves.Therefore,here we analyzed the variations in the NSC storage in diff erent organs of Chinese fi r(Cunninghamia lanceolata)under CO_(2)elevation and N addition and found that NSC concentrations and contents in all organs of Chinese fi r saplings increased remarkably under CO_(2)elevation.However,N addition induced diff erential accumulation of NSC among various organs.Specifi cally,N addition decreased the NSC concentrations of needles,branches,stems,and fi ne roots,but increased the NSC contents of branches and coarse roots.The increase in the NSC contents of roots was more pronounced than that in the NSC content of aboveground organs under CO_(2)elevation.The role of N addition in the increase in the structural biomass of aboveground organs was greater than that in the increase in the structural biomass of roots.This result indicated that a diff erent tradeoff between growth and NSC storage occurred to alleviate resource limitations under CO_(2)elevation and N addition and highlights the importance of separating biomass into structural biomass and NSC reserves when investigating the eff ects of environmental change on biomass allocation. 展开更多
关键词 Biomass partition CO_(2)elevation N deposition nonstructural carbohydrates Structural biomass
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Quantifying the effects of short-term heat stress at booting stage on nonstructural carbohydrates remobilization in rice 被引量:11
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作者 Fengxian Zhen Junjie Zhou +7 位作者 Aqib Mahmood Wei Wang Xini Chang Bing Liu Leilei Liu Weixing Cao Yan Zhu Liang Tang 《The Crop Journal》 SCIE CAS CSCD 2020年第2期194-212,共19页
Extreme heat stress events are becoming more frequent under anticipated climate change,which can have devastating impacts on rice growth and yield.To quantify the effects of short-term heat stress at booting stage on ... Extreme heat stress events are becoming more frequent under anticipated climate change,which can have devastating impacts on rice growth and yield.To quantify the effects of short-term heat stress at booting stage on nonstructural carbohydrates(NSC)remobilization in rice,two varieties(Nanjing 41 and Wuyunjing 24)were subjected to 32/22/27°C(maximum/minimum/mean),36/26/31°C,40/30/35°C,and 44/34/39°C for 2,4 and 6 days in phytotrons at booting stage during 2014 and 2015.Yield and yield components,dry matter partitioning index(DMPI),NSC accumulation and translocation were measured and calculated.The results showed that the increase of high-temperature level and duration significantly reduced grain yield by suppressing spikelet number per panicle,seed-setting rate,and grain weight.Heat stress at booting decreased DMPI in panicles,increased DMPI in stems,but had no significant effect on photosynthetic rate.Stem NSC concentration increased whereas panicles NSC concentration,stem NSC translocation efficiency,and contribution of stem NSC to grain yield decreased.Severe heat stress even transformed the stem into a carbohydrate sink during grain filling.The heat-tolerant Wuyunjing 24 showed a higher NSC transport capacity under heat stress than the heat-sensitive Nanjing 41.Heat degree-days(HDD),which combines the effects of the intensity and duration of heat stress,used for quantifying the impacts of heat stress indicates the threshold HDD for the termination of NSC translocation is 9.82°C day.Grain yield was negatively correlated with stem NSC concentration and accumulation at maturity,and yield reduction was tightly related to NSC translocation reduction.The results suggest that heat stress at booting inhibits NSC translocation due to sink size reduction.Therefore,genotypes with higher NSC transport capacity under heat stress could be beneficial for rice yield formation. 展开更多
关键词 Rice(Oryza SATIVA L.) Heat stress Yield components nonstructural carbohydrates TRANSLOCATION
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Polyphosphate Accelerates Transformation of Nonstructural Carbohydrates to Improve Growth of ppk-Expressing Transgenic Rice in Phosphorus Deficiency Culture 被引量:1
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作者 ZHU Jinling WEI Ruping +4 位作者 WANG Xin ZHENG Chaoqun WANG Mengmeng YANG Yicheng YANG Liuyan 《Rice science》 SCIE CSCD 2023年第3期235-246,共12页
Crop yield and quality are often limited by the amount of phosphate fertilizer added to infertile soils,a key limiting factor for sustainable development in modern agriculture.The polyphosphate kinase(ppk)gene-express... Crop yield and quality are often limited by the amount of phosphate fertilizer added to infertile soils,a key limiting factor for sustainable development in modern agriculture.The polyphosphate kinase(ppk)gene-expressing transgenic rice with a single-copy line(ETRS)is constructed to improve phosphate fertilizer utilization efficiency for phosphorus resource conservation.To investigate the potential mechanisms of the increased biomass in ETRS in low phosphate culture,ETRS was cultivated in a low inorganic phosphate(Pi)culture medium(15μmol/L Pi,LP)and a normal Pi culture medium(300μmol/L Pi,CP),respectively.After 89 d of cultivation in different concentrations of phosphate culture media,the total phosphorus,polyphosphate(polyP),biomass,photosynthetic rate,nonstructural carbohydrate(NSC)contents,related enzyme activities,and related gene expression levels were analyzed.The results showed that ETRS had a high polyP amount to promote the photosynthetic rate in LP,and its biomass was almost the same as the wild type(WT)in CP.The NSC content of ETRS in LP was higher than that of WT in LP,but slightly lower than that of WT in CP.PolyP notably promoted the sucrose phosphate synthase activities of ETRS and significantly down-regulated the expression levels of sucrose transporter genes(OsSUT3 and OsSUT4),resulting in inhibiting the transport of sucrose from shoot to root in ETRS.It was concluded that polyP can stimulate the synthesis of NSCs in LP,which improved the growth of ETRS and triggered the biological activities of ETRS to save phosphate fertilizer.Our study provides a new way to improve the utilization rate of phosphate fertilizer in rice production. 展开更多
关键词 POLYPHOSPHATE phosphate fertilizer nonstructural carbohydrate sucrose transporter gene sucrose phosphate synthase
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Interannual dynamics of stemwood nonstructural carbohydrates in temperate forest trees surrounding drought
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作者 Meghan J.Blumstein Morgan E.Furze 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期77-86,共10页
Interactions between water and carbon dynamics underlie drought-related tree mortality.While whole-tree water relations have been shown to play a key role in the response to and recovery from drought,the role of nonst... Interactions between water and carbon dynamics underlie drought-related tree mortality.While whole-tree water relations have been shown to play a key role in the response to and recovery from drought,the role of nonstructural carbohydrates(NSC) and how their storage and allocation changes surrounding drought events deserves further attention and is critical for understanding tree survival.Here,we quantified in situ NSC responses of temperate forest trees to the 2016 drought in the northeastern United States.Sugar and starch concentrations were measured in the stemwood of five tree species from 2014 to 2019,which allowed us to monitor NSCs in relation to climatic conditions before,during,and after the natural drought.We found that immediately following the drought,measured stemwood NSC concentrations decreased.However,NSC concentrations rebounded quickly within three years.Notably,trees allocated proportionally more to starch than to sugars following the 2016 drought.In winter 2017,starch comprised 45% of total stemwood stores,whereas starch made up only 1-2% in other years.Further,we modeled and assessed the climatic drivers of total NSC concentrations in the stem.Variation in total NSC concentrations was significantly predicted by the previous year’s temperature,precipitation,and standardized precipitation-evapotranspiration index(SPEI),with stemwood concentrations decreasing following hotter,drier periods and increasing following cooler,wetter periods.Overall,our work provides insight into the climatic drivers of NSC storage and highlights the important role that a tree’s carbon economy may play in its response and recovery to environmental stress. 展开更多
关键词 DROUGHT nonstructural carbohydrates Starch metabolism Forest trees
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Advances in selective conversion of carbohydrates into 5-hydroxymethylfurfural 被引量:1
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作者 Jie Liang Jianchun Jiang +4 位作者 Tingting Cai Chao Liu Jun Ye Xianhai Zeng Kui Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1384-1406,共23页
Converting carbohydrates into 5-hydroxymethylfurfural(5-HMF) is an attractive and promising route for value-added utilization of agricultural and forestry biomass resource. As an important platform compound, 5-HMF pos... Converting carbohydrates into 5-hydroxymethylfurfural(5-HMF) is an attractive and promising route for value-added utilization of agricultural and forestry biomass resource. As an important platform compound, 5-HMF possesses high active furan structure with hydroxymethyl and aldehyde group for production of various bio-chemicals and materials, meanwhile, which suffer from low stability and poor yield during the industrial biorefinery process. Hence, selective production of 5-HMF with high-yield and low-cost has attracted extensive attention from scientific and industrial researchers. This review sorted and described the latest advanced research on solvent and catalyst system, as well as energy field effect for production of 5-HMF with different feedstock in detail, emphatically discussing the solvent effect and its synergistic effect with other aspects. Besides, the future prospects and challenges for production of 5-HMF from carbohydrates were also presented, which provide a profound insight into industrial 5-HMF process with economic and environmental feature. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL BIOREFINERY SOLVENT SELECTIVITY CARBOHYDRATE
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The storage and utilization of carbohydrates in response to elevation mediated by tree organs in subtropical evergreen broad-leaved forests
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作者 Bin Xu Xueli Jiang +4 位作者 Yingying Zong G.Geoff Wang Fusheng Chen Zhenyu Zhao Xiangmin Fang 《Forest Ecosystems》 SCIE CSCD 2024年第1期52-61,共10页
Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate cl... Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems. 展开更多
关键词 nonstructural carbohydrates Structural carbohydrates ELEVATION Subtropical evergreen broad-leaved forests Tree organs
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT Non-structural carbohydrates C N P stoichiometric characteristics
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Impacts of Defoliation on Morphological Characteristics and Non-Structural Carbohydrates of Populus talassica × Populus euphratica Seedlings
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作者 Mengxu Su Zhanjiang Han +2 位作者 Zhen Zhao Xiaofeng Wu Jiaju Wu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1689-1703,共15页
Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forest... Leaves are important‘source’organs that synthesize organic matter,providing carbon sources for plant growth.Here,we used Populus talassica×Populus euphratica,the dominant species in ecological and timber forests,to simulate carbon limitation through artificial 25%,50%,and 75%defoliation treatments and explore the effects on root,stem,and leaf morphology,biomass accumulation,and carbon allocation strategies.At the 60th d after treat-ment,under 25%defoliation treatment,the plant height,specific leaf weight,root surface area and volume,and concentrations of non-structural carbohydrates in stem and root were significantly increased by 9.13%,20.00%,16.60%,31.95%,5.12%,and 9.34%,respectively,relative to the control.There was no significant change in the growth indicators under 50%defoliation treatment,but the concentrations of non-structural carbohydrates in the leaf and stem significantly decreased,showing mostly a negative correlation between them.The opposite was observed in the root.Under 75%defoliation treatment,the plant height,ground diameter,leaf number,single leaf area,root,stem,and total biomass were significantly reduced by 14.15%,10.24%,14.86%,11.31%,11.56%,21.87%,and 16.82%,respectively,relative to the control.The concentrations of non-structural carbohydrates in various organs were significantly reduced,particularly in the consumption of the starch concentrations in the stem and root.These results indicated that carbon allocation strategies can be adjusted to increase the con-centration of non-structural carbohydrates in root and meet plant growth needs under 25%and 50%defoliation.However,75%defoliation significantly limited the distribution of non-structural carbohydrates to roots and stems,reduced carbon storage,and thus inhibited plant growth.Defoliation-induced carbon limitation altered the carbon allocation pattern of P.talassica×P.euphratica,and the relationship between carbon reserves in roots and tree growth recovery after defoliation was greater.This study provides a theoretical basis for the comprehen-sive management of P.talassica×P.euphratica plantations,as well as a reference for the study of plantation car-bon allocation strategies in the desert and semi-desert regions of Xinjiang under carbon-limitation conditions. 展开更多
关键词 Populus talassica×Populus euphratica DEFOLIATION carbon limitation carbon allocation non-structural carbohydrates
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Study on the Changes of Non-structural Carbohydrates and Nitrogen Contents of Quercus aquifolioides Scrub along Different Elevation Gradient 被引量:2
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作者 黄亚洲 吴杰 +3 位作者 孟玉山 吕俊 王三根 朱万泽 《Agricultural Science & Technology》 CAS 2011年第4期576-580,共5页
[Objective] The aim was to compare the content changes between the non-structural carbohydrates(NSC)and the total nitrogen in various growing seasons,and to explore the response relationship between altitude and the... [Objective] The aim was to compare the content changes between the non-structural carbohydrates(NSC)and the total nitrogen in various growing seasons,and to explore the response relationship between altitude and the contents.[Method] Taking Quercus aquifolioides scrub which widely distributed in Zheduoshan in the west of Sichuan as the experimental objects,the changes between NSC and the toal nitrogen in various growing seasons at different altitude were studied.[Result] The results showed that the content of NSC in Quercus aquifolioides underground increased with the lift of elevation in the dormancy,but decreased in the early germination,growing period and growth stage.The content of NSC in the ground tissue changed non-linearly with increasing elevation.In addition,the total nitrogen of Quercus aquifolioides organizations was decreasing with increasing elevation in the dormant period,which did not change significantly in the other periods.This result implied that the content of NSC in Quercus aquifolioides underground was more sensitive to temperature.[Conclusion] The experiment laid basis for the exploration of the physical and ecological mechanism of underground plants adaptability to highland environment,their response to global climate changes and adjustment to high altitude ecological system. 展开更多
关键词 Quercus aquifolioides Total nitrogen NON-STRUCTURAL carbohydrates ELEVATION
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猪繁殖与呼吸综合征病毒谱系8毒株特异性单克隆抗体研制
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作者 任语馨 张杰 +4 位作者 高雁怩 孙杨杨 张路捷 白娟 姜平 《畜牧与兽医》 CAS 北大核心 2025年第1期111-118,共8页
猪繁殖与呼吸综合征病毒(PRRSV)流行毒株存在多种基因亚型(谱系)和抗原性差异,为了鉴别不同谱系流行毒株,选取PRRSV谱系8毒株BB0907(高致病性毒株)非结构蛋白2(NSP2)高变区基因片段(tNSP2),采用大肠杆菌表达制备获得NSP2重组蛋白,并免疫... 猪繁殖与呼吸综合征病毒(PRRSV)流行毒株存在多种基因亚型(谱系)和抗原性差异,为了鉴别不同谱系流行毒株,选取PRRSV谱系8毒株BB0907(高致病性毒株)非结构蛋白2(NSP2)高变区基因片段(tNSP2),采用大肠杆菌表达制备获得NSP2重组蛋白,并免疫BALB/c小鼠。结果:研制出5株NSP2单克隆抗体(3D6、6B2、6C3、8C2和8H6),小鼠腹水ELISA抗体效价均达1∶216000;5株单抗轻链类型都为Kappa型,3D6、6B2和6C8的重链类型为IgG1,8C2的重链类型为IgG2b,8H6重链类型为IgG2a;通过构建tNSP2蛋白截短体,Western blot鉴定出4个抗原表位,即^(485)GPLNFPTPSE^(494)、^(555)FPLAPSQNMG564、575EVLSEISDIL^(584)和^(585)NDTPAPVS^(593);间接免疫荧光试验结果显示,这些单抗均能与PRRSV谱系8毒株发生特异性反应,但与谱系1和谱系5毒株不反应。本研究为PRRSV分离毒株抗原鉴别诊断和生物学研究提供了有意义的研究材料。 展开更多
关键词 猪繁殖与呼吸综合征病毒 NSP2 单克隆抗体 B细胞表位
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非结构构件抗震韧性技术研究综述
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作者 刘福禄 辛力 +2 位作者 岳焱超 陈杰 张宇航 《山西建筑》 2025年第4期54-58,共5页
建筑非结构构件的抗震破坏程度较大,损失较为严重,但是其投资占比大、功能性强,因此越来越受到相关学者和工程师的重视,文章论述了非结构构件的抗震韧性技术研究进展,介绍了抗震韧性理念与非结构构件的分类,分析了建筑工程常见的非结构... 建筑非结构构件的抗震破坏程度较大,损失较为严重,但是其投资占比大、功能性强,因此越来越受到相关学者和工程师的重视,文章论述了非结构构件的抗震韧性技术研究进展,介绍了抗震韧性理念与非结构构件的分类,分析了建筑工程常见的非结构构件的震害表现与研究现状。结合实际工程经验,总结了国内现行规范中设计及施工方法和合理处理建议,希望能为非结构构件抗震韧性技术的后续发展提供参考。 展开更多
关键词 非结构构件 填充墙 吊顶 抗震支吊架
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穴位埋线联合丹莪妇康煎膏治疗子宫内膜异位症痛经疗效及对患者血清CA125的影响
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作者 刘玲慧 袁滢 +3 位作者 潘玉 张婕 丁天增 张天婵 《陕西中医》 CAS 2025年第1期122-125,共4页
目的:探究采用穴位埋线联合丹莪妇康煎膏疗法对子宫内膜异位症(EMs)痛经患者(气滞血瘀型)的临床治疗效果及其对血清糖类抗原125(CA125)的影响。方法:将66例EMs痛经患者(气滞血瘀型)随机分为两组,各33例。对照组给予丹莪妇康煎膏治疗,观... 目的:探究采用穴位埋线联合丹莪妇康煎膏疗法对子宫内膜异位症(EMs)痛经患者(气滞血瘀型)的临床治疗效果及其对血清糖类抗原125(CA125)的影响。方法:将66例EMs痛经患者(气滞血瘀型)随机分为两组,各33例。对照组给予丹莪妇康煎膏治疗,观察组在此基础上辅以穴位埋线疗法,两组均连续治疗3个月经周期。记录两组患者的临床疗效和不良反应;比较治疗前、治疗3个月经周期后经期视觉模拟评分量表(VAS)评分、痛经症状评分、气滞血瘀型痛经的中医证候积分及血清CA125水平变化。结果:观察组总有效率96.77%高于对照组86.67%(P<0.05);治疗3个月经周期后,两组的经期VAS评分、痛经症状评分、气滞血瘀型痛经中医证候积分及血清CA125水平均较治疗前降低,且在上述指标的改善幅度方面,观察组均显著优于对照组(均P<0.05);两组不良反应率比较差异无统计学意义(P>0.05)。结论:穴位埋线联合丹莪妇康煎膏可有效缓解气滞血瘀型EMs痛经及其伴随症状,改善中医证候,且能降低血清CA125水平、抑制异位内膜进展,提高临床疗效。 展开更多
关键词 子宫内膜异位症 痛经 穴位埋线 丹莪妇康煎膏 气滞血瘀型 血清糖类抗原125
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杂交稻与常规稻产量受干旱影响的Meta分析及干物质分配差异
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作者 毛紫琳 宋国庆 +3 位作者 马云静 牛鑫泽 曹凑贵 李萍 《华中农业大学学报》 北大核心 2025年第1期1-14,共14页
为探究干旱对杂交稻和常规稻干物质分配及产量的影响,通过Meta分析整合了1990-2020年中国境内干旱胁迫-水稻产量的文献结果,量化品种、干旱胁迫程度以及胁迫时期对水稻产量的影响,并于湖北省武汉市开展盆栽试验,以籼型杂交稻扬两优6号... 为探究干旱对杂交稻和常规稻干物质分配及产量的影响,通过Meta分析整合了1990-2020年中国境内干旱胁迫-水稻产量的文献结果,量化品种、干旱胁迫程度以及胁迫时期对水稻产量的影响,并于湖北省武汉市开展盆栽试验,以籼型杂交稻扬两优6号和汕优63、籼型常规稻黄华占和扬稻6号为试验材料,进一步研究干旱[土壤水势(-30±5) kPa]对抽穗开花期水稻的叶片与根系生理指标、干物质积累与分配的影响。Meta分析结果显示,干旱下水稻产量平均降幅为24.0%;与其他生育期相比,营养生长期干旱胁迫下水稻产量降幅最大,达24.4%;籼型杂交稻和籼型常规稻在干旱下的产量降幅分别为19.3%和13.8%,差异显著,表明常规稻在干旱下的产量相对稳定。武汉盆栽试验结果显示,干旱胁迫下水稻叶片水势和叶绿素含量、根系伤流速度、根系吸收面积与活跃吸收面积均显著下降,其中根系伤流速度的降幅最大,杂交稻与常规稻的降幅分别为94.29%和89.03%,而根系活力显著上升。干旱显著降低了水稻各部位干物质量,其中杂交稻叶片的可溶性糖含量与非结构性碳水化合物(non-structural carbohydrates,NSC)含量显著下降,降幅分别为37.73%和25.35%,常规稻叶片的可溶性糖含量与NSC显著上升,增幅分别为21.89%和10.49%。与杂交稻相比,干旱下常规稻的叶片与根系生理指标变幅更小,其叶、穗、根部的NSC含量积累较多,茎部的光合碳含量较高;常规稻的叶、穗、根在抽穗开花期积累的光合碳中NSC含量占比更大。因此,干旱下常规稻可能是通过积累较多的NSC来保证各器官能量代谢的稳定进行,从而维持较稳定的产量。 展开更多
关键词 杂交稻 常规稻 干旱胁迫 干物质分配 根系活力 产量 非结构性碳水化合物 META分析
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Identification of patients with advanced pancreatic cancer who might benefit from third-line chemotherapy
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作者 Bomi Kim Jaihwan Kim +4 位作者 Soomin Yang Jinwoo Ahn Kwangrok Jung Jong-Chan Lee Jin-Hyeok Hwang 《World Journal of Gastrointestinal Oncology》 2025年第2期74-83,共10页
BACKGROUND Survival rates of patients with advanced pancreatic cancer(APC)have been improved with palliative chemotherapy series.The current preferred first-line regimen consists of combination therapy of 5-fluorourac... BACKGROUND Survival rates of patients with advanced pancreatic cancer(APC)have been improved with palliative chemotherapy series.The current preferred first-line regimen consists of combination therapy of 5-fluorouracil(5-FU)/leucovorin(LV),irinotecan,and oxaliplatin(FOLFIRINOX)or gemcitabine plus albumin-bound paclitaxel(GNP).After failure of first-line chemotherapy,there are a few options for subsequent therapy including switch to the unused first-line regimen or nanoliposomal irinotecan and 5-FU/LV.However,there are limited studies on the efficacy of third-line chemotherapy after failure of second-line chemotherapy.AIM To identify patients with APC who might benefit from third-line chemotherapy.METHODS Medical records from a single tertiary hospital were retrospectively reviewed between 2012 and 2021.The study included patients with histologically or cytologically confirmed metastatic or locally APC who underwent first-line FOLFIRINOX or GNP and subsequently received third-line chemotherapy.Overall survival(OS)after diagnosis and OS after third-line chemotherapy(OS3)were defined as the interval from the diagnosis to all-cause death and the time between the initiation of the third-line chemotherapy to all-cause death,respectively.RESULTS A total of 141 patients were enrolled.The median patient age at diagnosis was 61.8 years(36.0-86.0),and 54.9%were male.The first-line regimen was FOLFIRINOX(67.4%)or GNP(32.6%).The second-line regimen was FOLFIRINOX(27.0%),GNP(52.5%),or other(20.6%).The median OS was 19.0 months,and the median OS3 and progression-free survival after third-line treatment were 15.3 and 7.3 weeks,respectively.With regard to the best tumor response during third-line chemotherapy,1.4%had partial response,24.8%had stable disease,and 59.6%had progressive disease.The following clinical factors before third-line chemotherapy affected OS3:Good performance status(PS),serum carbohydrate antigen 19-9(CA19-9)level<1000 U/mL,duration of second-line chemotherapy≥19 weeks,and no peritoneal seeding.CONCLUSION This study identified that patients with good PS,CA19-9<1000 U/mL,second-line chemotherapy≥19 weeks,and no peritoneal seeding before starting third-line treatment may benefit more from third-line chemotherapy. 展开更多
关键词 Pancreatic cancer CHEMOTHERAPY SURVIVAL Performance status Carbohydrate antigen 19-9
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PAK5与卵巢癌临床病理特征的相关性分析
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作者 巩婵婵 吕家盈 +2 位作者 展瑞 姚义兴 万琳琳 《诊断病理学杂志》 2025年第1期3-7,共5页
目的探究PAK5在卵巢癌及癌旁组织中的表达,同时观察PAK5与患者预后生存及临床病理参数之间的相关性。方法使用免疫组化技术评估卵巢肿瘤组织的PAK5、CA125、ER、PR、Ki-67的表达并进行评级,以确定与卵巢癌患者的FIGO分期、瘤体大小、患... 目的探究PAK5在卵巢癌及癌旁组织中的表达,同时观察PAK5与患者预后生存及临床病理参数之间的相关性。方法使用免疫组化技术评估卵巢肿瘤组织的PAK5、CA125、ER、PR、Ki-67的表达并进行评级,以确定与卵巢癌患者的FIGO分期、瘤体大小、患者年龄及是否存在淋巴结转移的关系。结果与卵巢癌周围正常组织相比,PAK5在卵巢癌组织中的表达明显增加,且PAK5的高表达与较大的瘤体、淋巴结转移以及较高的FIGO分期显著相关(P<0.05),同时与患者生存时间短相关(P<0.05)。此外,卵巢癌组织中PAK5的表达与Ki-67、CA125的表达之间存在着明显的正相关性,与ER表达呈负相关(P<0.05)。结论PAK5的表达在卵巢癌组织中明显增加,同时与患者的FIGO分期及不良预后等相关,PAK5有望成为临床中治疗卵巢癌新的作用靶点。 展开更多
关键词 PAK5 卵巢癌 免疫组化 CA125 临床病理
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木质纤维LCC化学键在不同处理过程中的断裂机理研究进展
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作者 朱宇童 李海潮 +2 位作者 胡愈诚 苗国华 许凤 《林业工程学报》 北大核心 2025年第1期1-11,共11页
以木质纤维生物质替代化石资源是解决当今环境问题的重要手段。木质纤维生物质细胞壁主要由纤维素、半纤维素和木质素3种组分通过复杂的相互作用形成,其中,木质素与半纤维素之间复杂的化学键是导致木质纤维原料顽抗性的主要原因之一,同... 以木质纤维生物质替代化石资源是解决当今环境问题的重要手段。木质纤维生物质细胞壁主要由纤维素、半纤维素和木质素3种组分通过复杂的相互作用形成,其中,木质素与半纤维素之间复杂的化学键是导致木质纤维原料顽抗性的主要原因之一,同时也是木质纤维素化学中最有争议的话题之一。目前木质纤维生物质处理和主要组分分离及转化技术已经取得了一定的进步,但总体上难以在保留木质素和半纤维素结构完整的前提下完全断裂木质素⁃碳水化合物复合体(LCC)化学键连接,进而导致大规模生物质精炼生产燃料、生物基化学品和材料仍然较困难。LCC中常见化学键在中性、酸性、碱性等不同的溶剂体系中反应性能不同,因此,需要针对不同的化学键设计绿色高效的处理方法,从而实现其精准选择性断裂,进而阐明LCC化学键选择性断裂机理。笔者综述了当前国内外学者对LCC之间化学键的键合机制及其主要化学键(如LCC醚/酯键、木质素β⁃O⁃4键等)断裂机理,重点介绍了LCC在各种处理过程中的变化,并探讨了不同处理手段存在的优势与不足,为木质纤维原料全组分分离及高效利用奠定理论与技术基础。 展开更多
关键词 木质素⁃碳水化合物复合体(LCC) 键合机制 化学键断裂 生物质转化
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Performance-based seismic design of nonstructural building components:The next frontier of earthquake engineering 被引量:20
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作者 Andre Filiatrault Timothy Sullivan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第S1期17-46,共30页
With the development and implementation of performance-based earthquake engineering,harmonization of performance levels between structural and nonstructural components becomes vital. Even if the structural components ... With the development and implementation of performance-based earthquake engineering,harmonization of performance levels between structural and nonstructural components becomes vital. Even if the structural components of a building achieve a continuous or immediate occupancy performance level after a seismic event,failure of architectural,mechanical or electrical components can lower the performance level of the entire building system. This reduction in performance caused by the vulnerability of nonstructural components has been observed during recent earthquakes worldwide. Moreover,nonstructural damage has limited the functionality of critical facilities,such as hospitals,following major seismic events. The investment in nonstructural components and building contents is far greater than that of structural components and framing. Therefore,it is not surprising that in many past earthquakes,losses from damage to nonstructural components have exceeded losses from structural damage. Furthermore,the failure of nonstructural components can become a safety hazard or can hamper the safe movement of occupants evacuating buildings,or of rescue workers entering buildings. In comparison to structural components and systems,there is relatively limited information on the seismic design of nonstructural components. Basic research work in this area has been sparse,and the available codes and guidelines are usually,for the most part,based on past experiences,engineering judgment and intuition,rather than on objective experimental and analytical results. Often,design engineers are forced to start almost from square one after each earthquake event: to observe what went wrong and to try to prevent repetitions. This is a consequence of the empirical nature of current seismic regulations and guidelines for nonstructural components. This review paper summarizes current knowledge on the seismic design and analysis of nonstructural building components,identifying major knowledge gaps that will need to be filled by future research. Furthermore,considering recent trends in earthquake engineering,the paper explores how performance-based seismic design might be conceived for nonstructural components,drawing on recent developments made in the field of seismic design and hinting at the specific considerations required for nonstructural components. 展开更多
关键词 nonstructural building components performance-based earthquake engineering seismic design and analysis
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