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1.
利用扩增片断长度多态性(AFLP)技术分析了鹀属(Emberiza)4种鹀(三道眉草鹀Emberi za cioides, 白头鹀Emberiza leucocephala, 白眉鹀Emberiza tristrami, 灰头鹀Emberiza spodocephala)基因组DNA的多态性. 在选取的39对引物中, 有11对能得到重复性好的多态性扩增条带, 每对引物扩增带数为27~76. 共得到535个标记位点, 其中429个为多态位点, 多态位点 比率达801%; 在UPGMA聚类关系图中, 4种鹀聚成一大类, 三道眉草鹀与白头鹀、 白眉鹀与灰头鹀分别两两相聚. 结果表明, AFLP可用于分析鹀属遗传多样性.  相似文献   

2.
应用扩增片段长度多态性(AFLP)技术研究鹀科8种28只鸟类的亲缘关系及遗传多样性. 28只个体分为两类, A类包括所有鹀属鸟类, B类包括铁爪鹀属和雪鹀属的铁爪鹀和雪鹀. 将A和B类中的不同物种分为不同分支: 栗斑腹鹀与三道眉草鹀和白头鹀为一支, 芦鹀、 红颈苇鹀和苇鹀为一支, 结果表明它们之间具有较近的亲缘关系. 其中雪鹀和铁爪鹀位于分支的最底部, 支持了其应从鹀属中分离的观点.  相似文献   

3.
2014年3-5月,利用计算机声音分析技术对黑鹳(Ciconia nigra)育雏期的鸣声进行了分析和研究.结果表明:黑鹳育雏期的鸣声可分为正常鸣叫声和惊恐声2种类型,二者语句类型大致相同,无明显的差别,均为首音素之后接着出现不定个数的凸型音素,结尾时都是平型音素,总体的趋势都是声音由低到高,再由高到低的一个渐变过程;句子持续时间、句子中音素个数和音素间的时间间隔在正常鸣声与惊恐声间无显著性差异(P0.05);但音素持续时间、最低频率和最高频率差异极显著(P0.01).黑鹳主要通过音素的重复,即改变首音素后的平型音素或凸型音素的个数实现句型的改变,以表达不同的含义.  相似文献   

4.
海豹科动物发声与其生命活动息息相关,记录其声信号并分析信号特征是海豹声学研究的一个重点.对斑海豹(Phoca largha)在空气中的发声及信号特性进行研究,对成年斑海豹与幼仔斑海豹的声信号特征进行比较,并利用Mat-lab R2011a等软件对这些信号进行时域和频域分析.结果表明:成年斑海豹在空气中声信号的持续时间分布在0.6~1.6s,平均值为1.15s,频谱能量集中分布在0.5~2kHz,峰值频率、3dB带宽和10dB带宽分别为(0.99±0.18),(0.22±0.17)和(0.69±0.16)kHz;幼仔斑海豹声信号平均持续时间为2.45s,比成年斑海豹长,频谱能量分布与成年斑海豹类似,峰值频率、3dB带宽和10dB带宽分别为(1.13±0.10),(0.11±0.10)和(0.61±0.44)kHz,其中峰值频率和3dB带宽变化范围均比成年斑海豹小.  相似文献   

5.
为确定雄性鸣禽前脑发声控制核团体积的侧别差异,进而为一侧优势提供形态学依据,以东北常见鸣禽栗鹀(Emberiza rutila)成体为实验材料,采用冰冻连续冠状切片、焦油紫染色、图像分析等方法比较了雄性栗鹀左右侧发声控制核团的体积差异.结果表明:雄性栗鹀前脑发声控制核团的体积有明显的侧别差异,即左侧高级发声中枢(high vocal center,HVC)、古纹状体粗核(nucleus robust archistriatum,RA)、嗅叶X区(Xarea)的体积均比右侧的体积大,分别是右侧同名核团体积的1.14,1.30和1.1倍;而与鸣唱运动无关的核团,如位于延髓的螺旋内核(nucleus spitiformis medialis,SpM)则无明显的侧别差异.说明鸣禽鸣唱运动的高级控制中枢在形态学上存在明显的侧别差异.  相似文献   

6.
厦门海域中华白海豚定位click信号特性   总被引:2,自引:0,他引:2  
对厦门海域中华白海豚的发声及信号特性进行研究,采用高频宽带数据记录系统获取了大量中华白海豚click信号,并利用Matlab软件和Excel 2007对这些信号进行时域和频域分析.结果表明:click信号通常以不同长度的序列形式出现,单个click信号长度分布在(33±4)μs;频谱能量分布广,低频至10kHz,高频达200kHz以上,具有单峰和双峰2种频谱结构,峰值频率、3dB带宽和10dB带宽分别为(113.3±16.3)、(48.3±14.2)和(113.3±16.4)kHz.中华白海豚click信号双峰的频率分布,为其在海底混响严重的浅海环境准确识别目标提供了保障.  相似文献   

7.
比较研究了中国长白山和俄罗斯符拉迪沃斯托克地区大耳蝠 (Plecotus auritus)飞行状态下的回声定位声波.结果表明,二者的回声定位声波均为微弱、不稳定的多谐波宽频带短调频型(modulated frequency).长白山大耳蝠回声定位声波由1~4个谐波组成,主频(45.4±9.6)kHz,能率环(5.1±2.5)%;符拉迪沃斯托克地区大耳蝠的回声定位声波由2~4个谐波组成,主频(48.0±9.7)kHz,能率环(7.0±3.1)%.二者的最高频率、最低频率、带宽、能率环以及声强均有显著差异.这种差异可能是由地理差异或性别差异等因素引起的.  相似文献   

8.
利用PCR方法对雀科9种鸟类11个线粒体基因组中3个主要的tRNA基因簇,即IQM(tRNAIle-tRNAGln-tRNAMet),WANCY(tRNATrp-tlRNAAla-tRNAsn-tRNACyB-tRNATyr)和HSL(tRNAHis-tRNASer(AGY)-tRNALeu(CUN))进行扩增和序列测定,这些tRNA基因序列中可变核苷酸位点占15%,其中59%出现在环区,且存在插入核苷酸;茎区相对保守,其中一些变异如双链的互补性碱基突变,G-u配对等对于维系tRNA二级结构的稳定性非常重要.利用11个线粒体tRNA基因全序列,以鹌鹑为外群构建了雀科9种鸟类的系统发育树,结果表明:黄雀与其它物种关系较远;鹀亚科中灰头鹀与雀亚科关系最近,而小鹀与三道眉草鹀比较特化,这与根据二级结构特征得出的结论相吻合.利用茎区序列构建的NJ树在鹀亚科物种的分类地位上存在分歧,可能是由于核苷酸数目较少,信息量小,在解决近缘物种间的分类地位时受到限制.结合线粒体tRNA基因二级结构特征比较和系统发育分析,初步认为线粒体tRNA基因二级结构特征对于推断雀科属间的分类地位具有较高的置信度.  相似文献   

9.
研究鼠类声行为,对探索鼠害控制的新方法有重要意义。在实验室条件下通过对11只褐家鼠(Rattus nor-vegicus)行为的观察和对860个叫声的分析,初步得知褐家鼠4种明显不同的声行为。单个体见到人时的惊恐叫声呈多谐变频的声谱结构,叫声的持续时间较长,平均在(473±271)ms,通常有3个主要的谐音,MPF为(2 820±258)Hz。当两个体一起发生追打时,势弱个体表现出与其行为相应的3种明显不同的叫声:打斗时的惊叫声频率最高,MPF为(5 091±1 365)Hz,频率范围宽达(9 225±3 292)Hz,大多是多谐结构;面对势强个体的叫声的振幅低,为(0.44±0.25)V,几呈多谐恒频结构,MPF和频宽分别为(2 917±1 463)Hz和(4 360±3 421)Hz;堵挡在通道口的叫声的持续时间长,叫声的频率最低,MPF为(1 384±878)Hz。  相似文献   

10.
本文借助CCD摄像机、高速A/D转换板 (采集速率为 1m/s)、图象采集卡、微型计算机和其它测试仪器 ,在喷油泵试验台上对透明供油系统中的汽泡进行试验研究。采用频谱分析的方法 ,对汽泡以不同方式消失时系统压力波动的频率结构进行研究 ,指出汽泡萎缩消失引起压力波动频率大约在 4kHz~ 1 1kHz,汽泡爆炸破碎造成高频振荡频率大约在 1 1kHz~ 2 0kHz,阐明泵端压力次波的升高率对汽泡的消失方式起决定作用。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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