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Late Oligocene fossil acorns and nuts of Quercus section Cyclobalanopsis from the Nanning Basin,Guangxi,South China被引量:1
2023年
Quercus is the largest genus within the Fagaceae and has a rich fossil record.Most of the fossil material is attributed to the subgenus Quercus based on leaves,pollen or rarely acorns and nuts.Fossil records of Q.section Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are scant.In this study,we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts:Q.paleodisciformis X.Y.Liu et J.H.Jin sp.nov.,Q.paleohui X.Y.Liu et J.H.Jin sp.nov.,Q.nanningensis X.Y.Liu et J.H.Jin sp.nov.and Q.yongningensis X.Y.Liu et J.H.Jin sp.nov.These species closely resemble the extant species Q.disciformis,Q.hui,Q.kerrii,and Q.dinghuensis.The occurrence of Q.section Cyclobalanopsis in the Oligocene stratum of Guangxi,South China,suggests that the section has diversified within its extant distribution center since the Oligocene.By combining records from other areas,we propose that the section first appeared in the middle Eocene of East Asia(Sino-Japan),has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene,respectively,and finally became restricted in East Asia since the Pleistocene.This indicates that the section originated and diversified in East Asia,before spreading into West Asia no later than the Oligocene and into southern Europe by the Pliocene.Subsequently it disappeared from South Europe and West Asia due to the appearance of the(summer dry)Mediterranean climate and widespread cooling during the Pleistocene.
Xiao-Yan LiuHan-Zhang SongXin-Kai WuJia-Rong HuWei-Ye HuangCheng QuanJian-Hua Jin
关键词:GUANGXI
橡实不同极性萃取物对α-淀粉酶和α-葡萄糖苷酶抑制作用研究被引量:3
2022年
探索橡实不同极性萃取物对α-淀粉酶和α-葡萄糖苷酶的抑制作用。采用40%乙醇和纤维素酶组合提取,石油醚、乙酸乙酯依次萃取分离,获得橡实粗提物、石油醚相、乙酸乙酯相、萃余水相。通过测定酶抑制作用,研究各极性萃取物的体外降糖活性,并利用高效液相色谱(HPLC)和分子对接实验验证各提取物可能的活性成分。结果表明:橡实不同极性萃取物对α-淀粉酶和α-葡萄糖苷酶均有明显的抑制作用,其中乙酸乙酯相抑制效果最佳,其对α-淀粉酶和α-葡萄糖苷酶IC_(50)分别为1.590±0.073 mg/g、3.927±0.019(×10^(-3) mg/g);通过HPLC含量测定发现乙酸乙酯相中6种活性成含量最高,鞣花酸含量为500.75±6.93 mg/g,高于其他组分10~50倍;分子对接结果表明只有鞣花酸与α-淀粉酶和α-葡萄糖苷酶有良好的结合活性。以上结果表明,鞣花酸可能是橡实乙酸乙酯萃取物抑制α-淀粉酶和α-葡萄糖苷酶的主要活性成分。
于聪聪姚玉阳耿雪营苗启明郭俊霞张艳贞米生权
关键词:橡实Α-淀粉酶Α-葡萄糖苷酶HPLC
栎实象超寄生与橡子物理性状的关系被引量:2
2021年
栎实象是栎属植物最为重要的种实害虫,橡子品质的优劣与栎实象寄生密切相关。为探究栎实象"超寄生"危害与栎属植物果实特征的关系,并揭示其产卵策略及对后代的影响,进而为栎实象高效防控和抗性树种选育提供理论依据,本研究选取了5种常见栎属植物,分析每种植物种子的果长、果径、体积、壳厚、果形指数及虫口密度与栎实象产卵选择的关系。通过单因素方差分析比较正常果、单寄生果和超寄生果之间的大小差异,使用独立样本t检验比较橡子内单寄生幼虫及超寄生幼虫重量差异性,并用线性回归拟合分析栎属植物果实特征对栎实象产卵偏好的影响。结果表明:5种栎属植物正常果壳平均厚度显著大于栎实象为害果的壳厚(P<0.05);线性回归模型表明超寄生率与栎属植物果长、果径、体积存在显著相关性(P<0.05),并且单寄生与超寄生及超寄生橡子前后逸出的二斑栎实象幼虫重量差异均不显著(P>0.05);二斑栎实象雌虫优先选择个体较大、果皮较薄的橡子进行取食和产卵,虽然超寄生增加了单个橡子中的幼虫数量,但其后代质量并未受到显著影响,说明雌性象甲对大橡子的产卵偏好可降低超寄生带来的不利影响。超寄生是栎实象应对不同寄主果实特征的一种行为适应策略。
刘亚宁李志红方林鑫王毅张威舒金平耿显胜王浩杰
关键词:栎属橡子
栗子刺皮、橡子中单宁抗氧化性的研究被引量:3
2019年
试验以栗子刺皮和橡子为原料,研究两种原料中单宁提取物的抗氧化活性。通过有机溶剂浸提法提取原料中的单宁,并测定两种单宁提取物对羟自由基和超氧阴离子的清除率,根据清除率的大小判断其抗氧化性的强弱。栗子刺皮和橡子单宁提取物对羟自由基最高清除率分别为86.35%和93.74%;对超氧阴离子自由基的清除率最高为90.55%和94.93%。结果表明,栗子刺皮和橡子单宁提取物对羟自由基和超氧阴离子自由基都有较强的清除能力,两种原料单宁提取物具有较强的抗氧化性。
刘婷婷杨新宇夏雪茹陈宝江
关键词:橡子抗氧化性
橡子色素对羊毛织物的染色工艺被引量:4
2019年
为挖掘羊毛织物传统染色工艺,拓宽现代植物染色的色彩内涵和色域范围,提高毛织物附加价值,使用皂矾为媒染剂,采用水煎法萃取橡子色素,对毛织物进行媒染,确定最佳染色工艺,不同染色工艺影响因素的显色规律,以及颜色特征值L~﹡、a~﹡、b~﹡、c~﹡值范围。实验结果表明:橡子色素羊毛织物后媒染可以染黑灰色调,染色效果为后媒染>前媒染>同媒染。最佳染液橡子色素质量分数为100%,最佳皂矾媒染剂质量浓度为5 g/L,最佳pH值6,最多染色次数为4次。复原了黑色和大黑色毡罽工艺,织物耐皂洗和耐摩擦色牢度均可达到3级以上,达到国家服用标准。证实了橡子色素可以染较深黑色,具有较大的开发价值。
毛选波
关键词:毛织物染色工艺植物染色橡子色谱
Acorn size and tolerance to seed predators:the multiple roles of acorns as food for seed predators,fruit for dispersal and fuel for growth被引量:2
2018年
Fitness of parents and offspring is affected by offspring size.In oaks(Quercus spp.),acorns vary considerably in size across,and within,species.Seed size influences dispersal and establishment of oaks,but it is not known whether size imparts tolerance to seed predators.Here,we examine the relative extent to which cotyledon size serves as both a means for sustaining partial consumption and energy reserves for developing seedlings during early stages of establishment.Acorns of 6 oak species were damaged to simulate acorn predation by vertebrate and invertebrate seed predators.Seedling germination/emergence and growth rates were used to assess seedling performance.We predicted that if cotyledons are important for dispersal,acorns should show tolerance to partial seed consumption.Alternatively,if the cotyledon functions primarily as an energy reserve,damage should significantly influence seedling performance.Acorns of each species germinated and produced seedlings even after removing>50%of the cotyledon.Seed mass explained only some of the variation in performance.Within species,larger acorns performed better than smaller acorns when damaged.Undamaged acorns performed as well or better than damaged acorns.There was no pattern among individual species with increasing amounts of damage.In some species,simulated invertebrate damage resulted in the poorest performance,suggesting alternative strategies of oaks to sustain damage.Large cotyledons in acorns may be important for attracting seed dispersers and sustaining partial damage,while also providing energy to young seedlings.Success of oak establishment may follow from the resilience of acorns to sustain damage at an early stage.
Andrew W.BARTLOWSalvatore JAGOSTARachel CURTISXianfeng YIMichael ASTEELE
关键词:ACORNSQUERCUS
Spatially biased dispersal of acorns by a scatter-hoarding corvid may accelerate passive restoration of oak habitat on California's largest island
2017年
Scatter hoarding by corvids (crows, jays, magpies, and nutcrackers) provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of habitat restoration, such disproportional storing of seeds in areas suitable for germin- ation and establishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub jays Aphelocoma insularis during scatter hoarding of acorns (Quercus spp.) on Santa Cruz Island. We use a large behavioral data set on the birds' behavior in combination with seedling surveys and spatial analysis to determine whether 1) island scrub jays disproportionally cache seeds in specific habitat types, and 2) whether the preferred habitat type is suitable for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub disproportionally while avoiding open and grassy areas. The areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island's oak habitat since the 1980s.
Mario B. PESENDORFERT. Scott SILLETTScott A. MORRISON
Habitat fragmentation alters predator satiation of acorns被引量:3
2017年
Aims Acorn weevils(Curculio spp.),endoparasitic granivorous insects,impede recruitment of fagaceous trees,and in turn affect community structure and ecosystem functioning.Previous studies have made considerable progress in elucidating local factors that contribute to seed predation by acorn weevils,but it is still not clear how habitat configurations interplay with local factors in influencing Curculio predation.In this study,we assessed the roles of crop size,landscape configurations(area and isolation)and their interactions on the predation rate of seeds by acorn weevils.Methods We studied acorn weevils feeding on the seeds of Castanopsis sclerophylla(Fagaceae)on two peninsulas and nine islands with varying areas and isolation levels in the Thousand-island Lake in Chun’an County,Zhejiang Province of China.Overall,crop size was estimated for 130 trees and predation status was assessed for 26207 seeds from these trees during two years.Generalized linear mixed models were performed to clarify how island area and isolation interplayed with crop size to determine predation rate on a single tree.Important Findings A negative relationship was detected between crop size and seed predation rate,indicating predator satiation at the tree level.This suggests that acorn weevils tend to stay sedentary once they have arrived at a suitable habitat.Habitat fragmentation had significant effects on seed predation such that predation rate was higher on larger,less isolated islands.Furthermore,the relationship between crop size and predation rate was significantly changed by both island area and isolation.This finding highlighted that the effects of habitat isolation might be overlooked relative to those of habitat loss.
Xin TongYu-Xuan ZhangRong WangMoshe InbarXiao-Yong Chen
关键词:CURCULIOISOLATION
麻栎橡子单宁脱除工艺优化及抗氧化性被引量:12
2017年
为探索高效可行的麻栎橡子单宁脱除工艺,实现其综合开发,以桥山林区麻栎橡子为原料,采用超声辅助乙醇法对影响单宁脱除率的因素进行单因素试验,选择影响显著的4个因素进行响应面分析,并测定单宁对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和羟自由基(·OH)的清除率,以探索麻栎橡子单宁的抗氧化活性。结果表明,液料比、乙醇体积分数、脱除温度、超声功率对单宁脱除率影响显著,模型拟合效果显著。最优脱除工艺为液料比42∶1(mL/g)、乙醇体积分数53%、脱除温度65℃、超声功率240 W,单宁脱除率为37.27%。麻栎橡子单宁抗氧化性与其质量浓度呈线性正相关,质量浓度为80 mg/L时,其对DPPH自由基的清除率可达75.56%,对·OH的清除率可达62.74%,可作为新型抗氧化剂。
薛文艳张文辉杨斌叶权平
关键词:BOX-BEHNKEN试验设计抗氧化活性
Production of micro-cuttings from acorns to test the plasticity of response to contrasting soil water regimes
2016年
We collected acorns from selected Quercus robur and Quercus petraea mother trees growing at sta- tions with different depths to the water table. We produced pairs of micro-cuttings from these single acorns. The obtained pairs of cuttings represented phenotypes of high similarity according to photosynthetic parameters. These pairs of cuttings were used to test the plasticity of response to contrasting water regimes. For each pair, one cutting was submitted to drought and the other was submitted to waterlogging. Drought response was recorded according to gas exchange traits (stomatal closure and water use effi- ciency). The response to waterlogging was recorded according to the capacity to form hypertrophied lenticels and to maintain the CO2 assimilation rate. Intermediary phenotypes presenting both high water use efficiency and the capacity to develop hypertrophied lenticels were expected.
julien parellesara belabbesfabienne tatin-froux
关键词:ACORNS

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