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Anti-detection technology of cat eye target based on decentered field lens 被引量:1
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作者 宋大林 常军 +1 位作者 赵一菲 张泽霞 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期333-337,共5页
Optoelectronic imaging equipment is easy to expose to active laser detection devices because of "cat eye" effect. In this paper, we propose a new structure of optical system to reduce the retroreflector effect of a ... Optoelectronic imaging equipment is easy to expose to active laser detection devices because of "cat eye" effect. In this paper, we propose a new structure of optical system to reduce the retroreflector effect of a cat eye target. Decentered field lens structure is adopted in the design without sacrificing imaging quality and clear aperture. An imaging system with±30° field of view is taken for example. The detailed design and simulation results are presented. The results indicate that this kind of optical system can reduce the retroreflection signal substantially and maintain acceptable imaging performance. 展开更多
关键词 geometric optical design cat eye effect reduction decentered field lens
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Cat's Eye:An Old Comedy
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作者 王莹 《海外英语》 2012年第12X期229-230,共2页
Northrop Frye' s four narrative forms:romance,tragedy,irony,and comedy can help explain the problematic structure of Margaret Atwood' s novel Cat' s Eye,in which the narrative,as well as certain other lite... Northrop Frye' s four narrative forms:romance,tragedy,irony,and comedy can help explain the problematic structure of Margaret Atwood' s novel Cat' s Eye,in which the narrative,as well as certain other literary features,indicates that it is essentially a come dy - a story of how a hero forms a desirable new society in the face of strong opposition.But this comedy is also ironic. 展开更多
关键词 ATWOOD cat’ s eye FRYE COMEDY
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Infrared Absorption Spectra of Serpentine Cat's Eye from Sichuan Province of China
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作者 卢保奇 夏义本 亓利剑 《Journal of Shanghai University(English Edition)》 CAS 2005年第4期365-368,共4页
Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assign... Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat' s eye includes two types: chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained. 展开更多
关键词 serpentine cats eye infrared spectrum absorption band assigned.
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New and Unusual Cat's Eyes and Asteriated Gems
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作者 Martin P.Steinbach Lore Kiefert Jeanette Fiedler 《宝石和宝石学杂志(中英文)》 CAS 2022年第1期1-11,共11页
The article describes 6 types of gemstones which show phenomena such as chatoyancy and asterism.The gemstones have not been described before,either because they come from new sources,or because the phenomenon has not ... The article describes 6 types of gemstones which show phenomena such as chatoyancy and asterism.The gemstones have not been described before,either because they come from new sources,or because the phenomenon has not been seen before in the type of gemstone described.Gems from the new sources are star garnet from the Karelia Province in Russia,and star garnet from the Jiangsu Province in China.Grandidierite usually does not show a cat’s eye effect,but the two described samples display a weak cat’s eye.An unusual white quartz from Brazil with a sharp cat’s eye is described,as well as a star sapphire with two differently coloured stars on each side of the cabochon,as well as a trapiche-type quartz.The stones were tested with gemmological,microscopic,and advanced techniques and the results are presented. 展开更多
关键词 cat’s eye star asterism chatoyancy QUARTZ grandidierite sAPPHIRE GARNET
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Entropy and Irreversibility in Classical and Quantum Mechanics 被引量:1
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作者 V.A.Antonov Boris P.Kondratyev 《Journal of Modern Physics》 2011年第6期519-532,共14页
Review of the irreversibility problem in modern physics with new researches is given. Some characteristics of the Markov chains are specified and the important property of monotonicity of a probability is formulated. ... Review of the irreversibility problem in modern physics with new researches is given. Some characteristics of the Markov chains are specified and the important property of monotonicity of a probability is formulated. Using one thin inequality, the behavior of relative entropy in the classical case is considered. Further we pass to studying of the irreversibility phenomena in quantum problems. By new method is received the Lindblad’s equation and its physical essence is explained. Deep analogy between the classical Markov processes and development described by the Lindblad’s equation is conducted. Using method of comparison of the Lind-blad’s equation with the linear Langevin equation we receive a system of differential equations, which are more general, than the Caldeira-Leggett equation. Here we consider quantum systems without inverse influ-ence on a surrounding background with high temperature. Quantum diffusion of a single particle is consid-ered and possible ways of the permission of the Schr?dinger’s cat paradox and the role of an external world for the phenomena with quantum irreversibility are discussed. In spite of previous opinion we conclude that in the equilibrium environment is not necessary to postulate the processes with collapses of wave functions. Besides, we draw attention to the fact that the Heisenberg’s uncertainty relation does not always mean the restriction is usually the product of the average values of commuting variables. At last, some prospects in the problem of quantum irreversibility are discussed. 展开更多
关键词 Markov Chains Irreversibility in Classical and Quantum Mechanics Lindblad Equation Caldeira-Leggett Equation Quantum Diffusion schrodinger’s cat Paradox Heisenberg’s Uncertainty Relation Collapse of Wave Function effect of sokolov
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Measuring Method of Radius of Curvature Based on Dual-Frequency Laser Interferometer
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作者 Wenlong Zhang Liang Miao Yu Liu 《Optics and Photonics Journal》 2016年第8期209-214,共6页
In order to achieve high-accuracy measurement of radius of curvature of optical sphere, ultra-high accuracy radius of curvature testing device is developed by dual-frequency laser interferometer and Fizeau interferome... In order to achieve high-accuracy measurement of radius of curvature of optical sphere, ultra-high accuracy radius of curvature testing device is developed by dual-frequency laser interferometer and Fizeau interferometer based on cat’s eye and confocal method. Through analyzing the error source models of radius of curvature testing, optical configuration of the testing device has been optimized. Precise environment control and real-time monitoring system is also established to reduce the errors caused by environment. Through the above processes, the radius of curvature measurement relative accuracy is better than 2 ppm. One optical sphere, R88.5 mm, test aperture 59 mm, has been tested. Testing result is 88499.465 ± 0.176 μm, meeting the design requirement. The method has high accuracy and practical advantages. 展开更多
关键词 Radius of Curvature cat’s eye and Confocal Method Dual-Frequency Laser Interferometer
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Adjustable-free and movable Nd:YVO_(4) thin disk laser based on the telecentric cat's eye cavity 被引量:4
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作者 王巍 高勇喜 +3 位作者 孙迪 杜潇 郭洁 梁晓燕 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第11期54-59,共6页
In this paper, we propose and demonstrate an adjustable-free and movable Nd:YVO_(4)thin disk laser based on the telecentric cat’s eye cavity. We design a V-shaped laser cavity containing two reflectors with Nd:YVO_(4... In this paper, we propose and demonstrate an adjustable-free and movable Nd:YVO_(4)thin disk laser based on the telecentric cat’s eye cavity. We design a V-shaped laser cavity containing two reflectors with Nd:YVO_(4)thin disks as the gain medium.The experimental results from the traditional plane-plane cavity, plane-telecentric cat’s eye cavity, and double telecentric cat’s eye cavity are compared. They show that plane-telecentric cat’s eye cavity laser can keep operating at the adjustablefree range of -6° to +6°, which is up to 60 times better than that of traditional plane-plane cavity. In the double telecentric cat’s eye case, the adjustable-free range is improved to-13° to +13°. Additionally, in the case of the double telecentric cat’s eye cavity, the output telecentric cat’s eye can achieve free movement within the horizontal range of ±20 mm. 展开更多
关键词 thin disk laser telecentric cat’s eye adjustable-free laser
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CAT’S EYE
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《男生女生(金版)》 2002年第5期60-63,共4页
关键词 cat’s eye
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“猫眼”效应用于主动式激光侦察的适用条件分析 被引量:32
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作者 蒋治国 谭吉春 +2 位作者 梁晶 曹丁象 张丽强 《激光技术》 CAS CSCD 北大核心 2005年第5期549-551,共3页
阐述了用激光主动扫描法侦察远方(隐蔽的)观察、瞄准仪器的原理及实验技术。以红外物镜为例,运用矩阵光学追迹法对影响“猫眼”效应回波强度的因素作定性、定量分析。研究结果表明,回波强度受光学仪器内部反射面倾斜和离焦的影响较大,... 阐述了用激光主动扫描法侦察远方(隐蔽的)观察、瞄准仪器的原理及实验技术。以红外物镜为例,运用矩阵光学追迹法对影响“猫眼”效应回波强度的因素作定性、定量分析。研究结果表明,回波强度受光学仪器内部反射面倾斜和离焦的影响较大,扫描光束的入射角和物镜相对孔径等因素对回波强度也有一定影响。例如在主动扫描装置距被探测观瞄仪器约1000m、扫描光束的入射角为0.3 rad条件下,反射面离焦及倾斜使得侦察装置接收到的回波能量与发射脉冲能量之比由理想条件下的3.3%分别下降到0.03%和0.016%。 展开更多
关键词 激光探测技术 隐藏光学仪器 反射 “猫眼”效应 矩阵光学
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基于激光主动探测的“猫眼效应”研究 被引量:12
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作者 李旭东 米建军 +6 位作者 茹志兵 张安峰 胡正良 周新妮 李宝珺 张琬琳 刘兵 《应用光学》 CAS CSCD 北大核心 2014年第2期342-347,共6页
针对基于"猫眼效应"的激光主动探测技术在光电对抗中的广泛应用,建立了迎面观瞄光电装置光学系统反光指数数学模型,并结合探测组件建立了探测距离数学模型,模拟了反光指数与内部特性参数间的数值关系及探测距离与迎面观瞄光... 针对基于"猫眼效应"的激光主动探测技术在光电对抗中的广泛应用,建立了迎面观瞄光电装置光学系统反光指数数学模型,并结合探测组件建立了探测距离数学模型,模拟了反光指数与内部特性参数间的数值关系及探测距离与迎面观瞄光电装置主要参数间的数值关系。为了验证建立的数学模型的正确性,利用研制的激光主动探测装置,分别以2.5mm、5.5mm孔径角镜和25mm、35mm、56mm孔径光电观瞄装置为目标,进行了最大探测距离模拟和验证实验,模拟值分别为1 290m、1 656m、866m、1 919m、1 226m,实验值分别达到1 100m、1 500m、800m、1 800m、1 200m。结果表明:最大探测距离模拟值和实验值有很好的一致性。 展开更多
关键词 激光 主动探测 猫眼效应 光电系统
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基于“猫眼效应”的激光主动侦察系统探测距离分析 被引量:14
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作者 董小刚 朱海军 殷刚 《激光与红外》 CAS CSCD 北大核心 2011年第1期67-70,共4页
为满足实战条件下激光主动侦察系统的设计需求,针对光学系统"猫眼效应"的离焦量分析,推导了脉冲激光探测距离的公式,并结合MATLAB数据仿真分析,得出了探测距离与CCD接收灵敏度、激光束散角、激光功率和大气能见度的关系曲线... 为满足实战条件下激光主动侦察系统的设计需求,针对光学系统"猫眼效应"的离焦量分析,推导了脉冲激光探测距离的公式,并结合MATLAB数据仿真分析,得出了探测距离与CCD接收灵敏度、激光束散角、激光功率和大气能见度的关系曲线。该研究对提高和改进系统的作战效能具有十分重要的意义。 展开更多
关键词 脉冲激光 主动侦察 作用距离 数据仿真 猫眼效应
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“猫眼”效应及其应用 被引量:11
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作者 田国周 王江 +1 位作者 钟鸣 吕百达 《激光杂志》 CAS CSCD 北大核心 2006年第4期16-18,共3页
本文对“猫眼”效应的研究进展作了综述,介绍了目前存在的几种“猫眼”效应模型,并推导出由于光敏面的离焦引起的发散角。对“猫眼”回波功率和漫反射小目标回波功率之比的物理意义作了解释。最后对“猫眼”效应应用中的一些问题作了讨论。
关键词 “猫眼”效应 光电侦察 探测距离 发散角
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空间目标识别中的激光探测技术 被引量:15
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作者 黄涛 胡惠灵 +1 位作者 胡以华 赵楠翔 《激光与红外》 CAS CSCD 北大核心 2010年第7期685-689,共5页
空间目标探测与识别技术是空间资源开发、空间安全等方向应用的前提条件,同其他方式相比,激光探测具有其突出的优势。当前传统的空间监视网是以微波雷达和光学望远镜为基础,激光探测与之相比具有系统简单、效费比高、能探测空间目标多... 空间目标探测与识别技术是空间资源开发、空间安全等方向应用的前提条件,同其他方式相比,激光探测具有其突出的优势。当前传统的空间监视网是以微波雷达和光学望远镜为基础,激光探测与之相比具有系统简单、效费比高、能探测空间目标多种特征参数的优点。介绍了激光探测空间目标中的空间目标轨道确定、几何形状估计、对装配的光学设备检测和对空间目标的振动识别等几种目标识别技术。最后分析了激光探测在空间目标识别中存在的问题和发展的方向。 展开更多
关键词 激光探测 空间目标 识别 逆合成孔径 猫眼效应 振动识别
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光电成像系统“猫眼效应”目标回波特征研究 被引量:2
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作者 李旭东 王立平 +1 位作者 米建军 李双全 《激光与红外》 CAS CSCD 北大核心 2022年第4期559-563,共5页
针对基于“猫眼效应”的激光主动探测技术在光电对抗中的广泛应用,对激光主动照明光源波长,被探测光电成像系统“猫眼效应”及探测系统最大探测距离之间的关系进行了分析研究,修正了与入射波长相关的反光指数模型及最大探测距离数学模型... 针对基于“猫眼效应”的激光主动探测技术在光电对抗中的广泛应用,对激光主动照明光源波长,被探测光电成像系统“猫眼效应”及探测系统最大探测距离之间的关系进行了分析研究,修正了与入射波长相关的反光指数模型及最大探测距离数学模型,并模拟了入射波长与最大探测距离间的数值关系。为了验证建立的数学模型的正确性,利用已研制的激光主动探测装置,选用焦距可调的光电成像传感器,进行了光电成像系统实焦与虚焦时最大探测距离验证实验,模拟值分别为1445 m与1751 m,实验值分别达到1230 m与1632 m。结果表明:实焦与虚焦时最大探测距离模拟值与实验值有很好的一致性。 展开更多
关键词 激光主动探测 猫眼效应 光电成像系统
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数字正交检波技术在主动探测中的应用研究 被引量:2
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作者 赵铭军 周彬 +1 位作者 胡永钊 曾晓东 《激光技术》 CAS CSCD 北大核心 2006年第2期212-214,224,共4页
提出基于光学系统的“猫眼”效应,应用单频调制的连续激光,对扫描式红外热成像目标进行有效探测的新方法。分析了光学系统的后向反射特性,针对回波信号特征,提出利用回波信号的相位信息,采用直接采样的数字正交检波技术实现对低信噪比... 提出基于光学系统的“猫眼”效应,应用单频调制的连续激光,对扫描式红外热成像目标进行有效探测的新方法。分析了光学系统的后向反射特性,针对回波信号特征,提出利用回波信号的相位信息,采用直接采样的数字正交检波技术实现对低信噪比回波信号的可靠检测,并在外场试验中应用该方案对实际目标回波信号获得了满意的检测结果。 展开更多
关键词 激光技术 光电对抗 扫描成像系统 红外 “猫眼”效应 正交检波
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减弱光学系统回波实现“猫眼”目标有效隐身 被引量:1
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作者 蒋治国 《激光杂志》 CAS CSCD 北大核心 2013年第4期70-71,共2页
针对主动式激光探测技术的主要原理,提出了一种在有限改变光电设备结构前提下减弱光学系统回波的隐身技术。运用光学追迹法对这种隐身技术作定量分析,并用实验进行验证。实验结果表明:有限改变光电设备结构能有效的减弱光学系统的回波,... 针对主动式激光探测技术的主要原理,提出了一种在有限改变光电设备结构前提下减弱光学系统回波的隐身技术。运用光学追迹法对这种隐身技术作定量分析,并用实验进行验证。实验结果表明:有限改变光电设备结构能有效的减弱光学系统的回波,从而达到隐身目的。 展开更多
关键词 隐身技术 红外望远物镜 回波 “猫眼”效应 矩阵光学
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猫眼效应中离焦量对激光回波发散角的影响 被引量:2
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作者 李会 陈青山 +1 位作者 李晓英 刘力双 《应用光学》 CAS CSCD 北大核心 2016年第1期147-151,共5页
平行光束或者激光束在光轴方向上照射焦平面成像系统时会产生猫眼效应,焦平面探测器安装的正交性与离焦量直接影响猫眼回波的光学特性,进而影响基于猫眼效应的探测系统的性能。针对猫眼效应中离焦量与后向反射光束发散角之间关系,利用... 平行光束或者激光束在光轴方向上照射焦平面成像系统时会产生猫眼效应,焦平面探测器安装的正交性与离焦量直接影响猫眼回波的光学特性,进而影响基于猫眼效应的探测系统的性能。针对猫眼效应中离焦量与后向反射光束发散角之间关系,利用物理光学进行分析,建立理论模型,对焦距为0.18m的焦平面探测成像系统进行数值计算得到:在离焦量为0.16mm时,发散角最小(0.019 mrad)。搭建实验系统,测试离焦量与猫眼回波发散角,测得离焦量在0.15mm附近存在最小的发散角为0.025mrad,与计算结果0.019mrad基本吻合。研究表明:1)负离焦对发散角的影响大于正离焦;2)猫眼回波发散角基本上随着离焦量绝对值的增加而变大,但是变化曲线并不关于零离焦量点对称,而是在某个正离焦处存在一个最小发散角。 展开更多
关键词 猫眼效应 离焦量 发散角 焦平面
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“猫眼”回波功率数值分析模型比较研究 被引量:1
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作者 刘明辉 陈青山 +1 位作者 李晓英 李响 《激光杂志》 北大核心 2017年第6期12-15,共4页
"猫眼"效应现象现已广泛应用于激光主动探测。为了更好地分析基于"猫眼"效应的探测系统的性能,分别采用几何光学与物理光学模型对目标回波功率进行理论分析,建立模型实现数值计算。针对轴上光束在不同传输距离、探... "猫眼"效应现象现已广泛应用于激光主动探测。为了更好地分析基于"猫眼"效应的探测系统的性能,分别采用几何光学与物理光学模型对目标回波功率进行理论分析,建立模型实现数值计算。针对轴上光束在不同传输距离、探测器光敏面分别处在光学系统焦平面和偏离焦平面情况的回波功率做了对比研究,并搭建探测系统进行了实验测试。研究结果表明:探测距离大于100m时,两种模型计算的回波功率吻合较好;小于100m时则存在明显差距;近距离时实验结果与几何模型计算数值更加接近,而远距离时物理光学模型计算结果、几何光学模型计算结果与实测数据非常接近。 展开更多
关键词 “猫眼”效应 回波功率 主动探测
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猫眼逆向调制通信链路信噪比分析 被引量:4
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作者 段帅军 樊桂花 +1 位作者 张来线 刘瑞丰 《激光与红外》 CAS CSCD 北大核心 2020年第11期1384-1388,共5页
猫眼逆向调制激光通信比其他逆向调制通信方式的通信速率更快,其原因是通信链路逆向调制端的猫眼结构可以实现匹配尺寸更小的调制器。本文在柯林斯衍射积分公式的基础上得到经过大气衰减作用的猫眼激光回波接收功率,并进一步结合光电探... 猫眼逆向调制激光通信比其他逆向调制通信方式的通信速率更快,其原因是通信链路逆向调制端的猫眼结构可以实现匹配尺寸更小的调制器。本文在柯林斯衍射积分公式的基础上得到经过大气衰减作用的猫眼激光回波接收功率,并进一步结合光电探测器噪声和大气湍流引起的闪烁效应,仿真分析了通信距离、湍流强度、激光波长、入射角度、猫眼孔径和接收口径对接收端信号信噪比的影响。 展开更多
关键词 逆向调制通信 猫眼效应 大气湍流 信噪比
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Effects of maternal stress induced by predator odors during gestation on behavioral and physiological responses of offspring in Brandt’s vole(Lasiopodomys brandtii)
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作者 Chen GU Wenjia WANG +4 位作者 Xiaoqian DING Shengmei YANG Aiqin WANG Baofa YIN Wanhong WEI 《Integrative Zoology》 SCIE CSCD 2018年第6期723-734,共12页
Maternal effects play a crucial role in regulating populations of small mammals and anti-predator behaviors of offspring.The present study investigated the effects of maternal stress induced by exposure to predator od... Maternal effects play a crucial role in regulating populations of small mammals and anti-predator behaviors of offspring.The present study investigated the effects of maternal stress induced by exposure to predator odors during gestation on the behavioral and physiological responses of offspring in Brandt’s vole(Lasiopodomys brandtii).Effects included changes in growth,behaviors,hormone levels in serum,and fosB/ΔfosB mRNA and FosB/ΔFosB protein expression in the hypothalamus.Our results showed that when pregnant voles were exposed to cat and rabbit urine odors for 18 days(1 h/day),the weight of the female offspring decreased;however,the thymus and ovary indices increased,compared with the control group.Male offspring of voles exposed to cat odor spent more time exploring and foraging,and showed a decrease in corticosterone(CORT)compared with voles in the control group.Both fosB/ΔfosB mRNA and FosB/ΔFosB protein expressions were downregulated in the hypothalamus of male offspring in the cat odor-exposed group compared to that in offspring in the control group.However,the mRNA levels of fosB/ΔfosB in the hypothalamus of female offspring did not decrease in response to cat urine odor.Our findings suggested that maternal stress induced by predator odors during gestation restrained the growth of female offspring and increased the duration of exploring and foraging behaviors of male offspring by regulating the HPA axis,which,in turn,reduced the sensitivity of offspring to unfamiliar environments and increased their probability of becoming prey. 展开更多
关键词 behaviors Brandt’s voles cat urine odor FosB/ΔFosB maternal effect
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