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Variaiton in the composition of small molecule compounds in the egg yolks of Asian Short-toed Larks between early and late broods
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作者 Shiyun Ding Na Zhu Shuping Zhang 《Avian Research》 SCIE CSCD 2023年第4期671-678,共8页
The egg yolks of birds contain most of the maternally derived materials required for embryo development and are an important factor influencing embryo development and offspring viability.Individual variation in egg-la... The egg yolks of birds contain most of the maternally derived materials required for embryo development and are an important factor influencing embryo development and offspring viability.Individual variation in egg-laying date frequently occurs in passerines inhabiting highly seasonal environments.Females laying in early and late stages of the breeding season encounter different environment temperatures and food conditions,which can affect the levels of metabolities in their bodies,thereby altering the transmission of these materials to the eggs.We test a hypothesis that yolk small molecule compounds of Asian Short-toed Lark(Alaudala cheleensis)could vary between early(mid-May)and late(mid-June)broods.Using the UHPLC-MS/MS method,683 compounds belonging to 21 compound groups are detected in the yolks.The contents of 18 compounds are significantly different between early and late broods.Ten differential compounds are significantly higher in the early laid eggs,among whichγ-aminobutyric acid,creatine,prostaglandins,palmitoleic acid,linoleic acid,and trans linoleic acid are related to low environment temperature response.The eggs laid in late stage exhibit significantly higher levels of 5-L-glutamyl-L-alanine andγ-glutamate-leucine,1,3-dimethyluric acid and mannose,which may be attributed to females in the late group consuming more insects.We suggest conducting a comprehensive investigation to reveal the yolk small molecule compounds mediated maternal effects on offspring phenotypes under varying ecological conditions. 展开更多
关键词 Asian Short-toed Lark Egg laying date Small molecule compounds Variation YOLK
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Mild spring temperature rising affects the anti-oxidation and immune functions of Asian Short-toed Larks
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作者 Na Zhu Tingting Liu +2 位作者 Fei Wang Wei Liang Shuping Zhang 《Avian Research》 CSCD 2020年第2期115-121,共7页
Background:Predicting the possibility of severe effects of global warming on animals is important for understanding the ecological consequences of climate change on ecosystem.Spring is the season during which birds ha... Background:Predicting the possibility of severe effects of global warming on animals is important for understanding the ecological consequences of climate change on ecosystem.Spring is the season during which birds have to physiologically prepare for the subsequent breeding period,and unusual spring temperature rising probably becomes a heat stress to the birds which have adapted to the low spring temperature.Therefore,it is necessary to understand the physiological effect of spring warming on the temperate birds.Methods:Using the activities of blood anti-oxidative enzymes(SOD,CAT,GPx)and the concentrations of serum immunogloblins(IgA,IgY,IgM)as indicators,we compared the anti-oxidative and immune functions of Asian Shorttoed Larks(Calandrella cheleensis)captured between 10 and 15 March,2015 and housed under conditions of 21°C and 16°C.Results:The SOD activities of birds in 21°C group were significantly lower than those in 16°C group on all the treatment days.The CAT activities of the birds in 21°C group were significantly lower than those in 16°C group on the 1 st,5 th,13 th,17 treatment days.The GPx activities of the birds in 21°C group were signifthicantly lower than those in 16°C group on the 1 st,13 th and 17 th,but significantly higher on the 21 st treatment day.The IgA,IgY and IgM concentrations of birds in 21°C group were significantly lower than those in 16°C group on all the treatment days.Conclusions:This study shows that spring temperature rising negatively influences antioxibative and humoral immune functions,which indicates that spring climate warming might reduce the fitness of the temperate passerine birds which have adapted to the low spring temperature. 展开更多
关键词 Mild temperature rising Anti-oxidant capacity Immunity Asian Short-toed larks Spring
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Systematics of the avian family Alaudidae using multilocus and genomic data
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作者 Per Alstrom Zeinolabedin Mohammadi +9 位作者 Erik D.Enbody Martin Irestedt Derek Engelbrecht Pierre-Andre Crochet Alban Guillaumet Loïs Rancilhac B.Irene Tieleman Urban Olsson Paul F.Donald Martin Stervander 《Avian Research》 SCIE CSCD 2023年第2期137-152,共16页
The family Alaudidae,larks,comprises 93-100 species(depending on taxonomy)that are widely distributed across Africa and Eurasia,with single species extending their ranges to North and northernmost South America and Au... The family Alaudidae,larks,comprises 93-100 species(depending on taxonomy)that are widely distributed across Africa and Eurasia,with single species extending their ranges to North and northernmost South America and Australia.A decade-old molecular phylogeny,comprising~80%of the species,revealed multiple cases of parallel evolution and large variation in rates of morphological evolution,which had misled taxonomists into creating many non-monophyletic genera.Here,we reconstruct the phylogeny of the larks,using a dataset covering one mitochondrial and 16 nuclear loci and comprising all except one of the currently recognised species as well as several recently proposed new species(in total 133 taxa;not all loci available for all species).We provide additional support using genome-wide markers to infer a genus-level phylogeny based on near-complete generic sampling(in total 51 samples of 44 taxa across 40 species).Our results confirm the previous findings of rampant morphological convergence and divergence,and reveal new cases of paraphyletic genera.We propose a new subfamily classification,and also that the genus Mirafra is divided into four genera to produce a more balanced generic classification of the Alaudidae.Our study supports recently proposed species splits as well as some recent lumps,while also questioning some of the latter.This comprehensive phylogeny will form an important basis for future studies,such as comparative studies of lark natural history,ecology,evolution and conservation. 展开更多
关键词 Phylogeny PHYLOGENOMICS Multispecies coalescent Lark PARAPHYLY Taxonomy Subfamily description
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基于自适应LARK特征的图像显著性检测算法
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作者 相入喜 朱锡芳 +1 位作者 吴峰 李辉 《常州工学院学报》 2017年第4期23-27,共5页
为了有效检测自然场景中的显著区域,提出一种简单高效的基于自适应LARK特征的图像显著性检测方法。首先自适应选取若干个有效的LARK特征分量,然后计算基于该特征的像素显著性值。为进一步增强图像像素的显著性,通过经典的超像素分割方... 为了有效检测自然场景中的显著区域,提出一种简单高效的基于自适应LARK特征的图像显著性检测方法。首先自适应选取若干个有效的LARK特征分量,然后计算基于该特征的像素显著性值。为进一步增强图像像素的显著性,通过经典的超像素分割方法计算图像的超像素颜色奇异性值。最后将这两者线性融合,形成自然场景中像素的最终显著性值。在国际通用数据集上测试,结果表明,该方法优于其他视觉显著区域检测计算方法,并且可以产生均匀突出的显著性图谱,在正确率和召回率上都有明显提高。 展开更多
关键词 显著性检测 LARK特征 颜色奇异性
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威廉·厄内斯特·亨利诗歌评析(英文)
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作者 彭素强 《海外英语》 2011年第9X期307-308,共2页
William Ernest Henley is a famous poet and suffers from tuberculosis seriously.In A Late Lark Twitters,he draws a comparison between the description of a scenery at sunset which is accompanied by the singing of a lark... William Ernest Henley is a famous poet and suffers from tuberculosis seriously.In A Late Lark Twitters,he draws a comparison between the description of a scenery at sunset which is accompanied by the singing of a lark and the then formulated wish to die in the very same way,to leave the earth at the end of life like the sun at the end of day. 展开更多
关键词 Lark DEATH free VERSE IMAGE
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基于LARK特征提取的AdaBoost人脸检测系统 被引量:3
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作者 王寅 《电子科技》 2014年第7期137-140,共4页
由于图像易受到外部条件及图像背景的影响,AdaBoost人脸检测方法在特征分类的过程中,单个分类器存在将人脸图像误判为非人脸图像的情况,致使分类器在检测过程中存在误差。文中通过研究AdaBoost人脸检测方法,并将LARK特征提取方法应用到... 由于图像易受到外部条件及图像背景的影响,AdaBoost人脸检测方法在特征分类的过程中,单个分类器存在将人脸图像误判为非人脸图像的情况,致使分类器在检测过程中存在误差。文中通过研究AdaBoost人脸检测方法,并将LARK特征提取方法应用到特征分类当中,使原有的方法上得到改进,从而有效提高了人脸检测的准确度。 展开更多
关键词 人脸检测 特征提取 LARK 特征分类 ADABOOST算法
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基于LARK特征提取的人脸检测方法
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作者 王寅 谭晓阳 《电子科技》 2012年第6期1-3,共3页
通过研究LARK特征提取方法,发现该方法可以对人脸图像的脸部信息进行有效的收集,并应用到人脸检测中。在检测时,先将检测的图像转换为灰度图像再进行检测,这样既可以完整地表示人脸的各部分特征,同时更易于处理,还可以减少计算量。
关键词 人脸检测 特征提取 LARK 核回归
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Endocrine response of early-hatching Asian Short-toed Lark nestlings exposed to cold temperature in a high-latitude grassland habitat 被引量:1
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作者 Jing Shang Liang Zhang +1 位作者 Xinyu Li Shuping Zhang 《Avian Research》 SCIE CSCD 2021年第4期750-758,共9页
Background:In high latitude grassland habitats,altricial nestlings hatching in open-cup nests early in the breeding season must cope with cold temperature challenges.Thyroid hormones(triiodothyronine,T_(3)and thyroxin... Background:In high latitude grassland habitats,altricial nestlings hatching in open-cup nests early in the breeding season must cope with cold temperature challenges.Thyroid hormones(triiodothyronine,T_(3)and thyroxine,T_(4))and corticosterone play a crucial role in avian thermoregulation response to cold.Investigating the endocrine response of altricial nestlings to temperature variation is important for understanding the adaptive mechanisms of individual variation in the timing of breeding in birds.Methods:We compared nest temperature,ambient temperature,body temperature,plasma T_(3),T_(4)and corticosterone levels in Asian Short-toed Lark(Alaudala cheleensis)nestlings hatching in the early-,middle-,and late-stages of the breeding season in Hulunbuir grassland,northeast China.Results:Mean nest temperature in the early-,middle-and late-stage groups was-1.85,3.81 and 10.23℃,respectively,for the 3-day-old nestlings,and 6.83,10.41 and 11.81℃,respectively,for the 6-day-old nestlings.The nest temperature significantly correlated with body temperature,plasma T_(3),T_(4)and corticosterone concentrations of nestlings.Body temperature of 3-day-old nestlings in the early and middle groups was significantly lower than that of the late group,but there was no significant difference between the nestlings in the early and middle groups.The T_(4)and T_(3)concentrations and the ratio of T_(3)/T_(4)of both 3-and 6-day-old nestlings in the early-stage group were significantly higher compared to the middle and late groups.The corticosterone levels of 3-day-old nestlings were significantly higher in the early-stage group compared to the middle-and late-stage groups.Conclusion:Nestlings hatching early responded to cold temperature by increasing thyroid hormones and corticosterone levels even in the early days of post hatching development when the endothermy has not been established.These hormones may play a physiological role in neonatal nestlings coping with cold temperature challenges. 展开更多
关键词 Endocrine response of early-hatching Asian Short-toed Lark nestlings exposed to cold temperature in a high-latitude grassland habitat
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An Interpretation of The Song of the Lark From the Marxist Feminism
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作者 杜平 《海外英语》 2019年第10期217-218,共2页
The Song of the Lark tells the story of young girl Thea who doesn’t give up and achieves her wish when faced with all sorts of setbacks. Based on the Marxist feminism, this paper is going to study the differences tha... The Song of the Lark tells the story of young girl Thea who doesn’t give up and achieves her wish when faced with all sorts of setbacks. Based on the Marxist feminism, this paper is going to study the differences that the female and male characters have experienced both in family and society in order to find out the root of females’oppressed status and reveal Cather’s writing in? tention—provide a possible way of improving the dilemma of women caused by capitalist ideology and the patriarchal ideology. 展开更多
关键词 The SONG of the Lark Sexual DIVISION of LABOR ALIENATION CAPITALISM PATRIARCHY
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Differential cell stress responses to food availability by the nestlings of Asian Short-toed Lark(Calandrella cheleensis)
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作者 Liang Zhang Lidan Zhao +2 位作者 Xinjie Zhang Wei Liang Shuping Zhang 《Avian Research》 CSCD 2019年第4期478-484,共7页
Background:Timing of breeding season of temperate passerines has been considered to be adjusted to their food availability.There is little work to reveal the cell stress responses of the nestlings hatched asynchronize... Background:Timing of breeding season of temperate passerines has been considered to be adjusted to their food availability.There is little work to reveal the cell stress responses of the nestlings hatched asynchronized with the food abundance peak,which is important for understanding the physiological link between the timing of breeding and the fitness of offspring.Methods:Using gene expression level of blood HSP70 and HSP90 as indicators,we compared the cell stress response of Asian Short-toed Lark(Calandrella cheleensis)nestlings hatched under conditions of low,mid or high food(grasshopper nymph)availability in 2017.Results:Nymph biomass,sample time and interaction of these two factors significantly influenced the blood gene expression level of HSP70 and HSP90 of Asian Short-toed Lark nestlings.HSP70 and HSP90 gene expression levels of the nestlings at 14:00 were significantly higher than those at 5:00.At either 5:00 or 14:00,the gene expression levels of HSP70 and HSP90 increase with the decrease of nymph biomass.Conclusions:These results indicate that food availability is an important environment factor inducing cellular stress of Asian Short-toed Lark nestlings.The interactive effect of the nymph abundance and sample time on the HSPs response may be related with the daily temperature variation of the grassland.Over cell stress response may be one of physiological factor mediating the effect of food availability and the nestling’s fitness. 展开更多
关键词 Asian Short-toed Lark nestling Cell stress Food availability HSP70 HSP90
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基于FPGA的特征降维算法实现
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作者 周晓 黄德湖 郑晓亮 《数字制造科学》 2021年第2期91-95,共5页
针对图像LARK(局部自适应回归核)特征提取过程中存在的信息冗余问题,利用PCA(主成分分析)技术对图像LARK特征进行降维处理,并且提出了相应的硬件架构。设计的硬件架构主要包括协方差矩阵运算模块、SVD分解模块和重映射模块。通过实验验... 针对图像LARK(局部自适应回归核)特征提取过程中存在的信息冗余问题,利用PCA(主成分分析)技术对图像LARK特征进行降维处理,并且提出了相应的硬件架构。设计的硬件架构主要包括协方差矩阵运算模块、SVD分解模块和重映射模块。通过实验验证,在保证精度的前提下,提出的架构能满足实时性要求。 展开更多
关键词 FPGA 降维 LARK特征 PCA
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Annoying neighbors: Multi-scale distribution determinants of two sympatric sibling species of birds
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作者 Alban GUILLAUMET Guillaume LEOTARD 《Current Zoology》 SCIE CAS CSCD 2015年第1期10-22,共13页
We tested the role of interspecific competition in driving species distribution at multiple spatial scales using two sibl- ing species of Galerida larks (G cristata and G. theklae) in Morocco (sympatry), Balearic ... We tested the role of interspecific competition in driving species distribution at multiple spatial scales using two sibl- ing species of Galerida larks (G cristata and G. theklae) in Morocco (sympatry), Balearic islands (G theklae only) and Israel (G cristata only). We first investigated regional-scale determinants by contrasting allopatric versus sympatric patterns in five distinct habitat types. We next focused on a single habitat used by both species, the coastal sand dunes. Dune quadrats were established along the Moroccan coast and completed by a quadrat in the nearest distinct landscape habitat. Poisson regressions were used to model Galerida counts together with ecological predictors as concerns the climate, topography, vegetation structure and soil gra- nulometry. At the local scale, both species preferred grey dunes over white sand dunes, and both were negatively affected by the abundance of the congeneric species in the dune. However, we found that G theklae tended to replace G. cristata in more arid sand dunes, even if the transition was not strictly clinal. Instead, the transition occurred when the surrounding landscape changed from coastal wetlands to bathas (grasslands with shrubs), highlighting the importance of habitat composition at the landscape scale. The fact that G cristata used bathas in allopatry, but not in sympatry, suggested that the competitive environment contri- buted to determine sand dune occupancy. We suggest that landscape-level effects may be pivotal in explaining species distribu- tion not only at the local scale, by affecting the pool of potential immigrants, but also at the regional scale, by contributing to species' range limit [Current Zoology 61 (1): 10-22, 2015]. 展开更多
关键词 ALLOPATRY Ecological release Galerida lark Interspecific competition Landscape Range limit
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LARK号线操纵特技模型飞机
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作者 戴小鹏 《航空模型》 2004年第3期9-14,共6页
这架模型飞机发动机汽缸工作容积比较大,模型尺寸也比较大;具有85公里/小时的较高线速度和5.3秒/360°的较低角速度;完成特技飞行动作质量与小模型相比有质的飞跃。制作和操纵过P2B-0、P2B—1等初级线操纵特技模型飞机的航模... 这架模型飞机发动机汽缸工作容积比较大,模型尺寸也比较大;具有85公里/小时的较高线速度和5.3秒/360°的较低角速度;完成特技飞行动作质量与小模型相比有质的飞跃。制作和操纵过P2B-0、P2B—1等初级线操纵特技模型飞机的航模爱好者,参照本文的插图,若成功做出这架大模型飞机,会向航模“实力派”更靠近一步。 展开更多
关键词 LARK号线操纵模型飞机 特技飞行 动作质量 模型尺寸
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