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How many species of Apodemus and Rattus occur in China? A survey based on mitochondrial cyt b and morphological analyses 被引量:9
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作者 Shao-Ying liu Kai He +5 位作者 Shun-De Chen Wei Jin Robert W.Murphy Ming-Kun Tang Rui liao feng-jun li 《Zoological Research》 SCIE CAS CSCD 2018年第5期309-320,共12页
Apodemus (mice) and Rattus (rats) are the top rodent reservoirs for zoonoses in China,yet little is known about their diversity.We reexamined the alpha diversity of these two genera based on a new collection of sp... Apodemus (mice) and Rattus (rats) are the top rodent reservoirs for zoonoses in China,yet little is known about their diversity.We reexamined the alpha diversity of these two genera based on a new collection of specimens from China and their cyt b sequences in GenBank.We also tested whether species could be identified using external and craniodental measurements exclusively.Measurements from 147 specimens of Apodemus and 233 specimens of Rattus were used for morphological comparisons.We analysed 74 cyt b sequences of Apodemus and 100 cyt b sequences of Rattus to facilitate phylogenetic estimations.Results demonstrated that nine species of Apodemus and seven species of Rattus,plus a new subspecies of Rattus nitidus,are distributed in China.Principal component analysis using external and craniodental measurements revealed that measurements alone could not separate the recognized species.The occurrence of Rattus pyctoris in China remains uncertain. 展开更多
关键词 Alpha diversity APODEMUS DNA-barcoding RATTUS TAXONOMY PHYLOGENIES New subspecies
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Effect of microstructure and mechanical properties on cutting force of different cast irons with similar tensile strength 被引量:1
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作者 Jiang-zhuo Ren Zong-liang li +3 位作者 Yi Xiong feng-jun li Feng-zhang Ren Alex A. Volinsky 《China Foundry》 SCIE 2019年第3期177-183,共7页
Flake graphite iron, compacted graphite iron and spheroidal graphite iron with various tensile strengths were cast. They were selected and grouped according to roughly the same tensile strength, and then the main cutt... Flake graphite iron, compacted graphite iron and spheroidal graphite iron with various tensile strengths were cast. They were selected and grouped according to roughly the same tensile strength, and then the main cutting force in each group was measured and compared. The microstructures of different cast irons were characterized. The relationship between the cutting force and microstructure was established. Results show that the graphite morphology in cast irons determines the strength. In order to obtain the same strength of the cast iron with sharply edged graphite, more or finer pearlite in the matrix is needed. Graphitic cast irons with high pearlite content and smaller pearlite interlamellar spacing have higher hardness. For the cast irons with different graphite morphologies, but almost the same tensile strength, the main cutting force is obviously different, along with the hardness. Harder cast irons have a greater cutting force, but the difference in cutting force is not proportional to hardness. 展开更多
关键词 GRAPHITE CAST irons CUTTING FORCE TENSILE strength microstructure
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Genomics and morphometrics reveal the adaptive evolution of pikas 被引量:1
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作者 Rui-Xiang Tang Jiao Wang +13 位作者 Yi-Fei li Cheng-Ran Zhou Guan-liang Meng feng-jun li Yue Lan Megan Price Lars Podsiadlowski Yan Yu Xu-Ming Wang Yin-Xun liu Bi-Song Yue Shan-lin liu Zhen-Xin Fan Shao-Ying liu 《Zoological Research》 SCIE CAS CSCD 2022年第5期813-826,共14页
Pikas(Lagomorpha: Ochotonidae) are small mouselike lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet) Plateau(QTP), we collected 226 ... Pikas(Lagomorpha: Ochotonidae) are small mouselike lagomorphs. To investigate their adaptation to different ecological environments during their dispersal from the Qinghai-Xizang(Tibet) Plateau(QTP), we collected 226 pikas and measured 20 morphological characteristics and recorded habitat information. We also sequenced the genome of 81specimens, representing 27 putative pika species.The genome-wide tree based on 4?090 coding genes identified five subgenera, i.e., Alienauroa, Conothoa,Lagotona, Ochotona, and Pika, consistent with morphometric data. Morphologically, Alienauroa and Ochotona had similar traits, including smaller size and earlier divergence time compared to other pikas.Consistently, the habitats of Alienauroa and Ochotona differed from those of the remaining subgenera. Phylogenetic signal analysis detected 83 genes significantly related to morphological characteristics, including several visual and hearingrelated genes. Analysis of shared amino acid substitutions and positively selected genes(PSGs) in Alienauroa and Ochotona identified two genes, i.e.,mitochondrial function-related TSFM(p.Q155E) and low-light visual sensitivity-related PROM1(p.H419Y).Functional experiments demonstrated that TSFM-155E significantly enhanced mitochondrial function compared to TSFM-155Q in other pikas, and PROM1-419Y decreased the modeling of dynamic intracellular chloride efflux upon calcium uptake. Alienauroa and Ochotona individuals mostly inhabit different environments(e.g., subtropical forests) than other pikas, suggesting that a shift from the larger ancestral type and changes in sensory acuity and energy enhancement may have been required in their new environments. This study increases our understanding of the evolutionary history of pikas. 展开更多
关键词 Pikas GENOMICS MORPHOMETRICS Adaptive evolution Sensory and energy functions
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A Strong Anti-Jamming Algorithm Based on FPGA for Estimating Loop Delay in Digital Predistortion System
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作者 feng-jun li Jing-Fu Bao +1 位作者 Hong-Yun Huang Shao-Chun Jin 《Journal of Electronic Science and Technology》 CAS 2012年第4期358-362,共5页
At present what are the key points focused in the research of loop-delay estimation for the digital predistorter in the radio frequency (RF) power amplifier system is reducing its complexity of engineering realizati... At present what are the key points focused in the research of loop-delay estimation for the digital predistorter in the radio frequency (RF) power amplifier system is reducing its complexity of engineering realization and improving anti-jamming ability and computational speed. Besides, opening up its application scope should be contained. For these targets, a novel method including integer loop delay estimation and fractional part is proposed. The integer part applies amplitude-difference summation function and the fractional one adopts the method of finite impulse response (FIR) linear interpolation. The algorithm finds wide applications. What is more, strong anti-jamming ability and low complexity are also its merits. Simulation results support the above opinion. Digital predistortion (DPD) system based on this algorithm achieves good performance. 展开更多
关键词 BASEBAND digital predistortion linearinterpolation loop delay estimation power amplifier.
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Mechanism of acupuncture treatment of primary insomnia
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作者 Mei-lin Zhang Yong Tang +4 位作者 Rui li Xi-Yu liu Zhong-Ting Song feng-jun li ZhenGuo Luo 《Journal of Hainan Medical University》 2021年第23期69-72,共4页
Insomnia is one of the most common clinical health problems,which can lead to a variety of complications and seriously affect human physical and mental health.Acupuncture has been used for treating insomnia for thousa... Insomnia is one of the most common clinical health problems,which can lead to a variety of complications and seriously affect human physical and mental health.Acupuncture has been used for treating insomnia for thousands of years,and is currently widely used as an alternative thehere is still a lack of up-to-date and comprehensive understanding of the mechanism of acupuncture for insorapy for insomnia all over the world.However,the mechanism of acupuncture for insomnia is still unclear,the mechanism research is relatively discrete,and tmnia.After summary and analysis in this study,it is found that acupuncture may improve sleeping by adjusting central neurotransmitter,insomnia-related hormone,circadian rhythm,sleep structure,and brain function.How to scientifically explain the scientific mechanism of acupuncture in treating insomnia has great challenges.I hope this study can provide reference for future research on the mechanism of acupuncture for insomnia. 展开更多
关键词 INSOMNIA ACUPUNCTURE Mechanism research
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Inverse-designed Jones matrix metasurfaces for high-performance meta-polarizers
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作者 王志强 李枫竣 +3 位作者 邓倩媚 万舟 李向平 邓子岚 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第2期192-199,共8页
Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve ... Polarizers have always been an important optical component for optical engineering and have played an indispensable part of polarization imaging systems.Metasurface polarizers provide an excellent platform to achieve miniaturization,high resolution,and low cost of polarization imaging systems.Here,we proposed freeform metasurface polarizers derived by adjoint-based inverse design of a full-Jones matrix with gradient-descent optimization.We designed multiple freeform polarizers with different filtered states of polarization(SOPs),including circular polarizers,elliptical polarizers,and linear polarizers that could cover the full Poincarésphere.Note that near-unitary polarization dichroism and the ultrahigh polarization extinction ratio(ER)reaching 50 d B were achieved for optimized circular polarizers.The multiple freeform polarizers with filtered polarization state locating at four vertices of an inscribed regular tetrahedron of the Poincarésphere are designed to form a full-Stokes parameters micropolarizer array.Our work provides a novel approach,we believe,for the design of meta-polarizers that may have potential applications in polarization imaging,polarization detection,and communication. 展开更多
关键词 metasurface inverse design Jones matrix polarization imaging
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