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Performance analysis and strategy optimization of mechanical defrosting for an Antarctic near-infrared telescope using aperture photometry
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作者 Jiali Chen Zhengyang Li +3 位作者 Zhixu Wu Jia’nan Cong Zichong Zhang Kaiwen Zheng 《Astronomical Techniques and Instruments》 2025年第6期358-365,共8页
Dome A,in Antarctica,offers an exceptional site for ground-based infrared astronomy,with its extremely low atmospheric infrared background noise and excellent seeing conditions.However,deploying near-infrared telescop... Dome A,in Antarctica,offers an exceptional site for ground-based infrared astronomy,with its extremely low atmospheric infrared background noise and excellent seeing conditions.However,deploying near-infrared telescopes in the harsh environment of Antarctica faces the critical challenge of frost accumulation on optical mirrors.While indium tin oxide heating films effectively defrost visible-band Antarctic astronomical telescopes,their thermal radiation at infrared wavelengths introduces significant stray light,severely degrading the signal-to-noise ratio for infrared observations.To address this limitation,we have designed a mechanical snow-removal system capable of efficiently clearing frost from sealing window surfaces at temperatures as low as–80°C.Aperture photometry of target sources,Canopus and HD 2151,revealed that after six days without intervention,floating snow extinction reduced target brightness by up to 3 magnitudes.Following mechanical defrosting,the source flux recovered to stable levels,with measured magnitudes showing rapid initial improvement followed by stabilization.Data analysis indicates that a frost removal strategy operating every 48 h,with each operation consisting of 4–6 cycles,enables efficient removal of frost and snow without introducing additional thermal noise.Future work will focus on optimizing the adaptive control algorithm and exploring novel low-temperature defrosting materials to extend the periods during which Antarctic infrared telescopes can operate unattended. 展开更多
关键词 Dome A Antarctic infrared thermal radiation Mechanical defrosting Aperture photometry
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脑深部电刺激损毁抑制前扣带回脑区改善小鼠抑郁样行为
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作者 杨昊南 袁正巍 +2 位作者 许军鹏 毛之奇 张剑宁 《中国组织工程研究》 北大核心 2026年第17期4366-4376,共11页
背景:前扣带回脑深部电刺激已成为精神类疾病如抑郁症外科治疗新疗法,但目前对电刺激的具体作用效果仍不清楚。前扣带回损伤可以显著改善小鼠抑郁行为,故推测通过脑深部电刺激模拟电消融可以治疗抑郁症。目的:结合光纤钙信号记录与C-fo... 背景:前扣带回脑深部电刺激已成为精神类疾病如抑郁症外科治疗新疗法,但目前对电刺激的具体作用效果仍不清楚。前扣带回损伤可以显著改善小鼠抑郁行为,故推测通过脑深部电刺激模拟电消融可以治疗抑郁症。目的:结合光纤钙信号记录与C-fos免疫组化技术,系统解析前扣带回脑深部刺激的神经调控机制,并对比脑深部电刺激与电消融术对小鼠抑郁样行为的干预效应。方法:①分组与造模:C57BL/6J小鼠随机分为对照组、模型+假刺激组、模型+脑深部电刺激组和模型+电消融组,后3组小鼠通过3.5周慢性束缚应激造模,4组小鼠均在前扣带回植入脑深部电刺激电极;②干预方案:脑深部电刺激组小鼠接受每日2 h时高频电刺激(130 Hz,200μA,50μs,持续1周);模型+假刺激组小鼠仅植入电极无电流刺激;模型+电消融组小鼠接受一次0.5 h的交流电刺激(参数为130 Hz,200μA);③行为学评估:通过强迫游泳实验、悬尾实验量化抑郁样行为;④环路机制解析:实时神经活动监测,光纤记录前扣带回-脑深部电刺激对前扣带回-基底外侧杏仁核环路的激活效应;⑤焦虑行为分析:旷场实验评估干预后小鼠焦虑样行为;⑥全脑激活图谱:C-fos免疫组化染色量化下游脑区神经元活动;⑦电消融验证小鼠抑郁样行为的改善效果。结果与结论:①行为学分析:强迫游泳实验显示,模型+脑深部电刺激组与模型+假刺激组小鼠不动时间显著高于对照组(P<0.05),但组间无差异;模型+电消融组小鼠不动时间显著低于模型+假刺激组(P<0.01);悬尾实验模型+脑深部电刺激组与模型+假刺激组小鼠不动时间无显著差异;旷场实验表明,脑深部电刺激组小鼠中央区停留时间与移动距离显著低于对照组(P<0.05),提示脑深部电刺激可能加剧焦虑样行为;②神经机制:光纤记录证实前扣带回-脑深部电刺激特异性激活前扣带回-基底外侧杏仁核环路;③C-fos染色显示:脑深部电刺激显著增强前扣带回下游脑区神经元活动。上述结果说明,传统高频前扣带回-脑深部电刺激虽能有效激活目标神经环路,但未能改善抑郁样行为,反而可能通过增强边缘系统活动加剧焦虑状态;而前扣带回功能抑制(电消融)表现出显著抗抑郁效应,为优化神经调控策略提供了新方向。 展开更多
关键词 脑深部电刺激 抑郁症 前扣带回 电消融 光纤记录
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Charge coupled devices (CCD) photometry and long-term optical variability of gamma-ray-loud BL Lacertae object Mkn 421 被引量:3
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作者 张雄 郑永刚 +2 位作者 张皓晶 胡绍明 谢照华 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2185-2192,共8页
Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magni... Evidence for the long-term optical curve variability and colour behaviour of the BL Lac object Mkn 421 is presented. Our results show that the amplitude of the optical variations of Mkn 421 is only about △B=4.7 magnitude in the B-band for its photometric history from 1899 to 2002. The results of optical photometric monitoring of the Mkn 421 from April 2000 to Jan 2002 are provided. During our observation, Mkn 421 shows significant rapid variations and exhibits short time variability of 2.42 hours in the B band. A strong correlation between the B - V colour index and the magnitude in the B band is found. Our charge coupled device (CCD) photometry of Mkn 421 shows that the measured results are in good agreement with the predicted optical variability period of about 23 years. 展开更多
关键词 BL Lac object Mkn 421 photometry mass of central black hole colour index
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All-fiber-transmission photometry for simultaneous optogenetic stimulation and multi-color neuronal activity recording 被引量:1
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作者 Zhongyang Qi Qingchun Guo +4 位作者 Shu Wang Mingyue Jia Xinwei Gao Minmin Luo Ling Fu 《Opto-Electronic Advances》 SCIE EI CAS 2022年第12期20-34,F0004,共16页
Manipulating and real-time monitoring of neuronal activities with cell-type specificity and precise spatiotemporal resolution during animal behavior are fundamental technologies for exploring the functional connectivi... Manipulating and real-time monitoring of neuronal activities with cell-type specificity and precise spatiotemporal resolution during animal behavior are fundamental technologies for exploring the functional connectivity, information transmission, and physiological functions of neural circuits in vivo. However, current techniques for optogenetic stimulation and neuronal activity recording mostly operate independently. Here, we report an all-fiber-transmission photometry system for simultaneous optogenetic manipulation and multi-color recording of neuronal activities and the neurotransmitter release in a freely moving animal. We have designed and manufactured a wavelength-independent multi-branch fiber bundle to enable simultaneous optogenetic manipulation and multi-color recording at different wavelengths. Further, we combine a laser of narrow linewidth with the lock-in amplification method to suppress the optogenetic stimulation-induced artifacts and channel crosstalk. We show that the collection efficiency of our system outperforms a traditional epi-fluorescence system. Further, we demonstrate successful recording of dynamic dopamine(DA) responses to unexpected rewards in the nucleus accumbens(NAc) in a freely moving mouse. We also show simultaneous dual-color recording of neuronal Ca2+ signals and DA dynamics in the NAc upon delivering an unexpected reward and the simultaneous optogenetic activating at dopaminergic terminals in the same location. Thus, our multi-function fiber photometry system provides a compatible, efficient, and flexible solution for neuroscientists to study neural circuits and neurological diseases. 展开更多
关键词 fiber photometry all-fiber-transmission multi-color optogenetic NEUROSCIENCE
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In vivo fiber photometry of neural activity in response to optogenetically manipulated inputs in freely moving mice 被引量:1
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作者 Liang Li Yajie Tang +6 位作者 Leqiang Sun Khaista Rahman Kai Huang Weize Xu Jinsong Yu Jinxia Dai Gang Cao 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2017年第5期47-58,共12页
In vito fber photometry is a powerful technique to analyze the dy namics of population neurons during fiunctional study of neuroscience.Here,we introduced a detailed protocol for fiber photometry-based calciun reordin... In vito fber photometry is a powerful technique to analyze the dy namics of population neurons during fiunctional study of neuroscience.Here,we introduced a detailed protocol for fiber photometry-based calciun reording in freely moving mice,covering from virus injection,fiber stub insertion,optogenetical stimulation to data procurement and analysis.Furthemnore,we applied this protocol to explore neuronal activity of mice latenal-posterior(LP)thalaric nucleus in response to optogenetical stimulation of primary visual cortex(V1)neurons,and explore axon clusters activity of optogenetically evoked V1 neurons.Final confirmation of virus-based protein expression in V1 and precise fber insertion indicated that the surgery procedure of this protocol is reliable for functional calcium recording.The scripts for data analysis and some tips in our protocol are provided in details.Together,this protocol is simple,low-cost,and effective for neuronal activity detection by fiber photometry,which will hep neuroscience researchers to carry out fiunctional and behavioral study in vivo. 展开更多
关键词 Fiber photometry surgical operation optogenetical stimulation neural activity freely moving recording
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THE BROAD-BAND CCD PHOTOMETRY AND DUST PRODUCTION RATES OF COMET HALE-BOPP
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作者 Huang Keliang 1 Hu Jingyao 2 Zhou Hongnan 1 (1. Department of Physics, Nanjing Normal University, Nanjing 210097) (2. Beijing Observatory, Chinese Academy of Sciences, Beijing 100080) 《中国科学院上海天文台年刊》 2000年第S1期44-50,共7页
Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp ... Based upon broad-band CCD observation data of comet Hale-Bopp obtained by a 60cm telescope at Xinglong Station of Beijing Astronomical Observatory during March-August, 1996, the photometric results of comet Hale-Bopp are reported. Using the photometric results, the dust production rate, radius and mass of nucleus of comet Hale-Bopp are estimated as follows: dM/dt~1.5×10 5 kgs -1, R n~35.5km, and M n~5.65×10 16kg. 展开更多
关键词 COMET HALE-BOPP - CCD photometry - DUST production rate
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Surface Photometry and Dynamical Properties of Lenticular Galaxies: NGC3245 as Case Study
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作者 Mohamed Adel Sharaf K. Mahmoud +1 位作者 E. Aly A. A. Alshaery 《International Journal of Astronomy and Astrophysics》 2012年第1期39-51,共13页
In this paper, surface photometry and dynamical properties of Lenticular galaxies will be developed and applied to NGC3245. In this respect, we established new relation between the intensity distribution I and the sem... In this paper, surface photometry and dynamical properties of Lenticular galaxies will be developed and applied to NGC3245. In this respect, we established new relation between the intensity distribution I and the semi-major axis a Moreover, some basic statistics of both independent and the dependent variables of the relation are also given. In addition to the I(a) relation , the Sérsic r1/n model is applied for the intensity profile I(r) resulting in an estimation of the effective radius, re, and the surface brightness it encloses, μe. Both relations (I(a) and I(r)) are accurate as judged by the precision criteria which are: the probable errors for the coefficients , the estimated variance of the fit and the Q value (the square distance between the exact solution and the least square estimated solution) where all very satisfactory. Correlation coefficients between some parameters of the isophotes are also computed. Finally as examples of applications of surface photometry we determined the dynamical properties: mass, density, potential distributions, as well as distributions of escape and circular speeds in terms of Sérsic model. 展开更多
关键词 SURFACE photometry DYNAMICAL GALAXIES
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Recovering 3D structural properties of galaxies from SDSS-like photometry
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作者 Elmo Tempel Antti Tamm +1 位作者 Rain Kipper Teeter Tenjes 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第10期1613-1628,共16页
Because of the 3D nature of galaxies, an algorithm for constructing spatial density distribution models of galaxies on the basis of galaxy images has many advan- tages over approximations of the surface density distri... Because of the 3D nature of galaxies, an algorithm for constructing spatial density distribution models of galaxies on the basis of galaxy images has many advan- tages over approximations of the surface density distribution. We present a method for deriving the spatial structure and overall parameters of galaxies from images and estimate its accuracy and derived parameter degeneracies on a sample of idealised model galaxies. The test galaxies consist component with varying proportions and of a disc-like component and a spheroidal properties. Both components are assumed to be axially symmetric and coplanar. We simulate these test galaxies as if they had been observed in the SDSS project through ugriz filters, thus gaining a set of realis- tically imperfect images of galaxies with known intrinsic properties. These artificial SDSS galaxies were thereafter remodelled by approximating the surface brightness distribution with a 2D projection of a bulge+disc spatial distribution model and the restored parameters were compared to the initial ones. Down to the r-band limiting magnitude of 18, errors in the restored integral luminosities and colour indices re- main within 0.05 mag and errors in the luminosities of individual components within 0.2 mag. Accuracy of the restored bulge-to-disc luminosity ratio (B/D) is within 40% in most cases, and becomes worse for galaxies with low B/D, but the general balance between bulges and discs is not shifted systematically. Assuming that the intrinsic disc axial ratio is ≤ 0.3, then the inclination angles can be estimated with errors 〈 5° for most of the galaxies with B/D 〈 2 and with errors 〈 15° up to B/D = 6. Errors in the recovered sizes of the galactic components are below 10% in most cases. The axial ratios and the shape parameter N of Einasto's distribution (similar to the Sersic index) are relatively inaccurate, but can provide statistical estimates for large samples. In general, models of disc components are more accurate than models of spheroidal components for geometrical reasons. 展开更多
关键词 methods: numerical -- galaxies: general -- galaxies: photometry --galaxies: structure
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UBVVI Surface Photometry of the Spiral Galaxy NGC 300 in the Sculptor Group
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作者 Sang Chul Kim Hwankyung Sung +1 位作者 Hong Soo Park Eon-Chang Sung 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2004年第4期299-310,共12页
We present UBVI surface photometry over a 20.5' × 20.5' area of the late-type spiral galaxy NGC 300. We have derived isophotal maps, surface brightness profiles, ellipticity profiles, position angle profi... We present UBVI surface photometry over a 20.5' × 20.5' area of the late-type spiral galaxy NGC 300. We have derived isophotal maps, surface brightness profiles, ellipticity profiles, position angle profiles, and color profiles. By merging our I-band measurements with those of Boker et al. based on Hubble Space Telescope observations, we have obtained combined I-band surface brightness profiles for the region 0.02' < r < 500' and have decomposed the profiles into three components: a nucleus, a bulge, and an exponential disk. 展开更多
关键词 galaxies: spiral - galaxies: photometry - galaxies: individual(NGC 300) - galaxies: nuclei
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Involvement of A5/A7 noradrenergic neurons and B2 serotonergic neurons in nociceptive processing:a fiber photometry study
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作者 Shunpei Moriya Akira Yamashita +6 位作者 Daiki Masukawa Junichi Sakaguchi Yoko Ikoma Yoshimune Sameshima Yuki Kambe Akihiro Yamanaka Tomoyuki Kuwaki 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第4期881-886,共6页
In the central nervous system,the A6 noradrenaline(NA)and the B3 serotonin(5-HT)cell groups are well-recognized players in the descending antinociceptive system,while other NA/5-HT cell groups are not well characteriz... In the central nervous system,the A6 noradrenaline(NA)and the B3 serotonin(5-HT)cell groups are well-recognized players in the descending antinociceptive system,while other NA/5-HT cell groups are not well characterized.A5/A7 NA and B25-HT cells project to the spinal horn and form descending pathways.We recorded G-Ca MP6 green fluorescence signal intensities in the A5/A7 NA and the B25-HT cell groups of awake mice in response to acute tail pinch stimuli,acute heat stimuli,and in the context of a non-noxious control test,using fiber photometry with a calcium imaging system.We first introduced G-Ca MP6 in the A5/A7 NA or B25-HT neuronal soma,using transgenic mice carrying the tetracycline-controlled transactivator transgene under the control of either a dopamineβ-hydroxylase or a tryptophan hydroxylase-2 promoters and by the site-specific injection of adeno-associated virus(AAV-Tet O(3 G)-G-Ca MP6).After confirming the specific expression patterns of G-Ca MP6,we recorded G-Ca MP6 green fluorescence signals in these sites in awake mice in response to acute nociceptive stimuli.G-Ca MP6 fluorescence intensity in the A5,A7,and B2 cell groups was rapidly increased in response to acute nociceptive stimuli and soon after,it returned to baseline fluorescence intensity.This was not observed in the non-noxious control test.The results indicate that acute nociceptive stimuli rapidly increase the activities of A5/A7 NA or B25-HT neurons but the non-noxious stimuli do not.The present study suggests that A5/A7 NA or B25-HT neurons play important roles in nociceptive processing in the central nervous system.We suggest that A5/A7/B2 neurons may be new therapeutic targets.All performed procedures were approved by the Institutional Animal Use Committee of Kagoshima University(MD17105)on February 22,2018. 展开更多
关键词 A5 NA neurons A7 NA neurons B25-HT neurons DBH-tTA mice fiber photometry G-CaMP6 mCherry monoaminergic signaling nociception TPH-t TA mice
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生物酶活性测试技术研究进展 被引量:1
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作者 侯晓妮 刘明东 +3 位作者 吕昊 叶德萍 马丽侠 周李华 《生物技术进展》 2025年第1期58-66,共9页
生物酶在工业、农业、医药、环境保护等领域生产中发挥着巨大的作用。活性作为生物酶的主要性能参数,直接影响着生物酶的质量和应用。随着科学技术的发展,生物酶活性检测也产生了许多新技术新方法。回顾了国内外生物酶活性主流的测试技... 生物酶在工业、农业、医药、环境保护等领域生产中发挥着巨大的作用。活性作为生物酶的主要性能参数,直接影响着生物酶的质量和应用。随着科学技术的发展,生物酶活性检测也产生了许多新技术新方法。回顾了国内外生物酶活性主流的测试技术和方法,包括光谱法、电化学法、色谱法、放射性标记法、质谱法、表面等离子体共振法、表面增强拉曼光谱法,综述了不同方法的基本原理、适用条件及优缺点,并提出了生物酶活性测试结果的准确性和可靠性的建议,以期对生物酶活性检测、方法选取、质量控制和产品应用提供指导。 展开更多
关键词 生物酶 活性 光谱法 电化学法 色谱法 质谱法 表面等离子体共振法 表面增强拉曼光谱法
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小天体建模约束条件下的观测规划方法研究
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作者 王睿 郭良库 +1 位作者 赵巍 刘鹏 《空间控制技术与应用》 北大核心 2025年第5期38-47,共10页
小天体三维模型是深空探测任务获取的重要科学数据之一.由于建模需要大量观测图像数据,且对观测条件和成像质量等要求高,探测器需要较频繁的轨道机动以获取满足要求的观测图像,因此需要协同考虑光照、目标表面观测覆盖率、燃料消耗和数... 小天体三维模型是深空探测任务获取的重要科学数据之一.由于建模需要大量观测图像数据,且对观测条件和成像质量等要求高,探测器需要较频繁的轨道机动以获取满足要求的观测图像,因此需要协同考虑光照、目标表面观测覆盖率、燃料消耗和数据下行传输量等多种因素.本文基于小天体光度学三维建模方法原理,提出了一种面向光度法建模的观测规划方法;在远距离探测建模得到的低分辨率三维模型基础上,使用遗传算法规划探测器近距离详细观测方案.该方法基于建模成像的观测约束条件,给出考虑覆盖率和光照-阴影关系的高效成像策略,有效提升了测绘过程中的观测效率,在满足三维重建精度需求的前提下,减少了探测器轨道机动,降低了图像数据的传输量. 展开更多
关键词 小天体探测 基于光度学的三维建模 遗传算法 观测规划
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CIE光辐射测量研究和标准化进展
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作者 李倩 刘慧 +1 位作者 赵伟强 潘建根 《照明工程学报》 2025年第2期9-13,共5页
国际照明委员会(Commision Internationale de l′Eclairage,简称CIE)是光和照明领域世界权威学术和标准化组织,旨在推动照明科学的研究、标准化与国际间合作。CIE光辐射物理测量分部(D2)致力于研究制定紫外-可见-红外辐射、综合辐射评... 国际照明委员会(Commision Internationale de l′Eclairage,简称CIE)是光和照明领域世界权威学术和标准化组织,旨在推动照明科学的研究、标准化与国际间合作。CIE光辐射物理测量分部(D2)致力于研究制定紫外-可见-红外辐射、综合辐射评估以及材料和光源光学特性的物理测量方法及相关测量设备的计量方法、光学特性和性能评估方法研究。本文介绍了CIE D2的主要职责、最新工作进展及战略规划,并介绍了与照明产业密切相关的已发布或正在研制中的光辐射测量研究和标准化项目。这些项目包括CIE物理光度学系统、光辐射源的空间光谱辐射测量、标准照明体和校准用参考光谱、暂态光调制测量和基于成像测量装置的光环境测量方法等。 展开更多
关键词 光辐射测量 研究战略 光度学 光谱辐射测量
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基于Apollo月壤样品二向反射测量数据的光度学分析
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作者 谷亚亚 杨亚洲 +1 位作者 刘建忠 张莉 《空间科学学报》 北大核心 2025年第2期328-339,共12页
了解不同观测角度下的月壤光散射特征,不仅可以为月表光谱数据的光度校正或解混提供参考依据,还可以帮助解译月壤物质的化学特性或物理性质. Hapke模型被广泛地应用于月表光度学分析中,但不同研究中所选取的模型参数组合不同,导致得到... 了解不同观测角度下的月壤光散射特征,不仅可以为月表光谱数据的光度校正或解混提供参考依据,还可以帮助解译月壤物质的化学特性或物理性质. Hapke模型被广泛地应用于月表光度学分析中,但不同研究中所选取的模型参数组合不同,导致得到的月壤光度参数存在差异,无法进行直接的对比分析.为了更好地理解月壤光度特性,基于6个不同Apollo月壤样品的二向反射测量数据,选用不同参数组合的Hapke模型进行光度学分析,获取了月海和高地月壤的光度参数.同时,对比了二项勒让德形式相函数与Henyey-Greenstein相函数,以及3参数与5参数Hapke模型在月壤光度学分析中的适用性.分析结果可为月壤光谱数据处理过程中的模型选择与后续解译提供参考. 展开更多
关键词 月壤光度 相函数 光度参数 观测几何 Hapke模型
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基于SiPM传感的油中局部放电多光谱检测技术
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作者 贺浩原 潘成 +3 位作者 秦少瑞 姚雨杭 朱庆东 唐炬 《绝缘材料》 北大核心 2025年第10期92-101,共10页
硅光电倍增管(SiPM)具有很高的光学检测灵敏度,应用于电力设备绝缘状态监测和诊断前景广阔。本文对比了变压器油中SiPM传感器与高频电流传感器(HFCT)的局部放电检出特性,并研究了基于SiPM传感的油中局部放电多光谱特性。结果表明:对于... 硅光电倍增管(SiPM)具有很高的光学检测灵敏度,应用于电力设备绝缘状态监测和诊断前景广阔。本文对比了变压器油中SiPM传感器与高频电流传感器(HFCT)的局部放电检出特性,并研究了基于SiPM传感的油中局部放电多光谱特性。结果表明:对于针板放电,检测距离小于50 cm时,SiPM传感器的检测效果优于HFCT;对于悬浮放电,检测距离小于55 cm时,SiPM传感器的检测效果优于HFCT。针板放电下,350~480 nm波段内检测到的放电数量占比最高,480~577 nm波段内检测到的放电数量占比随着电压等级的升高而增加;悬浮放电下,350~480 nm波段内检测到的放电数量占比较少,而480~577 nm波段内检测到的放电数量占比较多。多光谱信息在油中局部放电类型的识别和严重程度诊断方面具备应用潜力。 展开更多
关键词 局部放电 硅光电倍增管 光测法 多光谱
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Impact of Low-Earth Orbit Satellites on the China Space Station Telescope Observations
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作者 Huai-Jin Tang Xiao-Lei Meng +2 位作者 Hu Zhan Xian-Min Meng You-Hua Xu 《Research in Astronomy and Astrophysics》 2025年第11期6-20,共15页
It is projected that more than 100,000 communication satellites will be deployed in Low-Earth Orbit(LEO)over the next decade.These LEO satellites(LEOsats)will be captured frequently by the survey camera onboard the Ch... It is projected that more than 100,000 communication satellites will be deployed in Low-Earth Orbit(LEO)over the next decade.These LEO satellites(LEOsats)will be captured frequently by the survey camera onboard the China Space Station Telescope(CSST),contaminating sources in the images.As such,it is necessary to assess the impact of LEOsats on CSST survey observations.We use the images taken by the Hubble Space Telescope in its F814W band to simulate i-band images for the CSST.The simulation results indicate that LEOsats at higher altitudes cause more contamination than those at lower altitudes.If 100,000 LEOsats are deployed at altitudes between 550 and 1200 km with a 53°orbital inclination,the fraction of contaminated sources in a 150 s exposure image would remain below 0.50%.For slitless spectroscopic images,the contaminated area is expected to be below 1.50%.After removing the LEOsat trails,the residual photon noise contributes to relative photometric errors that exceed one-tenth of the total error budget in approximately 0.10%of all sources.Our investigation shows that even though LEOsats are unavoidable in CSST observations,they only have a minor impact on samples extracted from the CSST survey. 展开更多
关键词 techniques:photometric light pollution methods:data analysis techniques:image processinggalaxies:photometry gravitational lensing:weak
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智能手机数字比色法快速检测不同水样中的磷酸盐 被引量:1
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作者 陈亚 张江群 +4 位作者 常子涵 王涛 胡梦 张艳 龙星宇 《分析测试学报》 北大核心 2025年第7期1426-1432,共7页
针对过量的磷酸盐会导致水体富营养化,对生态环境有着重大威胁且目前磷酸盐检测技术存在成本高、耗时长、不能满足快速检测等问题,该文基于磷钼蓝比色法建立了一种快速测定水体中磷酸盐含量的智能手机数字比色法(SDC)。探究了不同智能... 针对过量的磷酸盐会导致水体富营养化,对生态环境有着重大威胁且目前磷酸盐检测技术存在成本高、耗时长、不能满足快速检测等问题,该文基于磷钼蓝比色法建立了一种快速测定水体中磷酸盐含量的智能手机数字比色法(SDC)。探究了不同智能手机型号、RGB值、拍摄倍数、光源的种类及光强度等因素对数字比色法测定磷酸盐结果的影响。结果表明,以HUAWEI P50e手机、R-通道值作为测定值、3×拍摄倍数、白色光源以及高光强条件下,磷酸盐的Red值(R值)在0~800μg·L^(−1)范围内呈良好的线性关系(r2=0.997 6);方法检出限为1.63μg·L^(−1),定量下限为4.89μg·L^(−1)。在优化条件下,对100、400μg·L^(−1)磷酸盐溶液平行测定10次的相对标准偏差(RSD)分别为0.35%和0.31%,400μg·L^(−1)磷酸盐的日内、日间RSD(n=5)分别为0.38%和0.42%。将该法应用于4种不同实际水体(自来水、雨水、思雅河水、白云湖水)中磷酸盐的检测,加标回收率为96.1%~101%,表明方法可行且结果准确可靠,为实现现场快速测定水环境中磷酸盐提供了新思路。 展开更多
关键词 数字比色法 智能手机 快速检测 磷钼蓝光度法 磷酸盐
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抗体及其免疫复合物表征分析技术研究进展
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作者 蒋婷婷 米薇 申屠旭萍 《分析试验室》 北大核心 2025年第5期794-800,共7页
抗体药物及抗体免疫复合物的表征分析技术不断发展,但现有的分析方法存在固有局限性,限制了抗体及免疫复合物的准确分析。近年来,通过质量光度法、多角度光散射、电喷雾差分电迁移率、非变性质谱等新方法,实现了从不同角度更加完整地表... 抗体药物及抗体免疫复合物的表征分析技术不断发展,但现有的分析方法存在固有局限性,限制了抗体及免疫复合物的准确分析。近年来,通过质量光度法、多角度光散射、电喷雾差分电迁移率、非变性质谱等新方法,实现了从不同角度更加完整地表征抗体及其免疫复合物,并延伸至抗体寡聚化和免疫复合物形成的研究。本文对现有抗原-抗体复合物表征技术检测现状进行了简要阐述,总结了4种新技术在抗体及其免疫复合物中的研究进展,并对这些技术的局限性和未来发展方向进行了分析和展望。 展开更多
关键词 抗体 抗原抗体相互作用 质量光度法 多角度光散射 电喷雾差分电迁移率
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Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior
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作者 Xirong Xu Shoumin Xuan +3 位作者 Shuai Chen Dan Liu Qian Xiao Jie Tu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1721-1734,共14页
The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain functio... The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders. 展开更多
关键词 ANXIETY ASTROCYTES basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry GLUTAMATE LDN-212320 TRANSPORTER
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小鼠脑电图/肌电图与多脑区光纤记录联用及其在癫痫模型中的应用
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作者 高彤彤 陈晨 +3 位作者 叶苇一 邓茂 侯恒浩 陈迁 《解剖学报》 2025年第5期533-540,共8页
目的 开发一种脑电图(EEG)/肌电图(EMG)与多脑区光纤记录联用的方法,以同步捕捉癫痫发作时大脑整体和特定脑区的神经元活动变化。方法 以小鼠颅骨中缝为界,将头部分为左右两个区域,一侧植入EEG电极(EEG/EMG),另一侧在纹状体、海马区、... 目的 开发一种脑电图(EEG)/肌电图(EMG)与多脑区光纤记录联用的方法,以同步捕捉癫痫发作时大脑整体和特定脑区的神经元活动变化。方法 以小鼠颅骨中缝为界,将头部分为左右两个区域,一侧植入EEG电极(EEG/EMG),另一侧在纹状体、海马区、内嗅皮层和丘脑埋植光纤,同步监测脑电、肌电和钙信号动态变化。结果 通过EEG/EMG与多脑区光纤记录联用,观察小鼠不同行为状态下多脑区神经元活动、脑电以及肌电的差异;在海人藻酸(KA)诱导的癫痫模型中,小鼠大脑神经元异常同步化放电伴随纹状体、海马区、内嗅皮层和丘脑的钙信号变化,其中海马区的变化最早出现。结论 成功实现小鼠EEG/EMG与多脑区光纤记录的联用,通过该方法在KA诱导的癫痫模型中同步记录了多脑区钙信号、脑电和肌电信号的异常变化。 展开更多
关键词 电信号 钙信号 癫痫 脑电图 光纤光度法 小鼠
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