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| 1 | Leaf choice in black-and-white snub-nosed monkeys Rhinopithecus bieti is related to the physical and chemical properties of leaves显示文摘To understand the effects of the chemical and physical properties of plant leaves on food choice in Rhinopithecus bieti,we collected mature leaves of nine food and five non-food plant species at the southernmost part of the species's range.Chemical properties such as fat, ash, crude protein (CP), total phenolics (TP), and fiber content including neutral detergent fiber(NDF), acid detergent fiber (ADF), lignin, celluloses and hemicelluloses, and physical toughness were measured. R. bieti tendedto choose leaves with lower fiber content, higher ash, a higher ratio of CP/ADF, and lower toughness. No difference was foundfor fat, crude protein, total phenolics, hemicelluloses and lignin between food and non-food leaves. Even though the ratio ofCP/ADF is generally regarded as a good indicator for colobine food choice, the difference in the ratio of CP/ADF between foodand non-food leaves was only the result of differences in ADF. Since positive correlations were found between ADF and toughnessfrom all leaves (both food and non-food species), and toughness of leaves was likely easier for R. bieti to sense than fibercontent via mastication, the toughness of leaves may function as a predictor of food choice in this species. | Zhipang HUANG Sheng HUO Shuguo YANG Liangwei CUI Wen XIAO | 2010 | Current Zoology2010，56，6： | 6 |
| 2 | Broadband transmission-type 1-bit coding metasurface for electromagnetic beam forming and scanning显示文摘Coding metasurfaces make it possible to manipulate electromagnetic(EM)waves digitally by means of several discrete particles.Hence,there have been rapid advances in this field recently.Here we propose a novel design of a broadband transmission-type coding metasurface,which is valid to both x-and y-polarized EM incidences from 8.1-12.5 GHz while satisfies the requirements of 1-bit coding without changing the polarization.Two types of multi-layer coding particles with different geometrical parameters are adopted to represent the digital states'0'and'1',which are easily promoted to terahertz and optics through modifying the size scale.To verify the ability to manipulate the EM waves,we first adopt the coding metasurface to achieve broadband beam forming by converting spherical waves to plane waves and realize high-directivity pencil beam in far field with low side lobes.We further arrange the particles according to the coding sequence 010101…to steer two symmetrical beams in different directions controlled by frequencies with the maximum range of the scanning angle of 30°-50.5°.The good agreements between the simulated and measured results validate the proposed broadband coding metasurface,indicating its huge potential in communication and radar imaging systems. | RuiYuan Wu Lei Bao LiangWei Wu TieJun Cui | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，8： | 5 |
| 3 | Long-term variations of X-ray pulse profiles for the Crab pulsar:data analysis and modeling显示文摘The pulse profiles of the Crab pulsar(as well as some other pulsars)vary with time.They can lead to a major source of intrinsic timing noise,which lacks a detailed physical model.The phase separation?between the first left peak(P1)and the second right peak(P2)is a key parameter that shows the variations of pulse profiles for the Crab pulsar.It was found that the evolution of?has a tendency with increasing rates of 0.82?±0.25?,0.80?±0.54?,and 0.77?±0.28?per century for the 2-6,6-15,and15-60 ke V bands,respectively.Furthermore,the flux ratios(P2/P1)of X-ray pulse profiles in the three bands were calculated,and the derived flux ratios were consistent with the radio and X-ray measurements of the Insight-HXMT.In addition to discovering the physical origin of the pulse changes,the high-SNR X-ray pulse profiles were simulated in the annular gap model,and two model parameters(e.g.,the maximum emission heights of the two peaks)were observed to slightly affect the variations of peak separation.We fitted the long-term variations of emission heights of the two peaks and discovered that the emission heights showed increasing tendencies with time.Variations of these emission heights induced a characteristic period derivative,and a complete formula for both the magnetic dipole radiation and wind-particle-induced variations of the moment of inertia was used for the pulsar’s spin-down to obtain the variation rate˙αof the magnetic inclination angle,which was-1.60?per century.Intrinsic timing noise is observed to be mainly induced by the variations of pulse profiles,which might correlate with a characteristic spin period derivative arising from the fluctuations of the emission regions.This work will lay a foundation for understanding the origin of intrinsic timing noise and making high-precision timing models in the future. | LunHua Shang YuanJie Du XiangQun Cui ShiJun Dang JiGuang Lu JunTao Bai QiJun Zhi YouLi Tuo LinLi Yan LiangWei Huang XinYuan Zhang XiaoMin Bei QingQing Lin GuoJun Qiao Hua Shen RiHong Zhu | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，10： | 2 |
| 4 | Winter pairs of ruddy shelducks at Lashihai Lake,southwest China显示文摘It has been suggested that pairing behavior during winter in migratory ducks represents a trade-off between costs(defense of the female)and benefits(early access to females).To investigate the benefits and costs for both sexes in wintering pairs of ruddy shelducks(Tadorna ferruginea),we compared time budgets for paired males and females,and surveyed the sex ratio of the birds wintering at Lashihai Lake,southwest China.The behavior of the paired ruddy shelducks was monitored for 5 activity types:feeding,resting(including sleeping),preening,drinking and warning.Feeding was the most dominant activity.The feeding time of both sexes increased as the winter season progressed.However,the paired females always spent significantly more time feeding and less time warning than the paired males.Paired ruddy shelducks had access to better feeding grounds than unpaired individuals,resulting in a food benefit for paired individuals over single individuals.Because the sex ratio of the wintering population was strongly male biased(M:F=1.44:1.00),the paired male also gained the benefit of accessing a female in advance of the breeding season. | Ruichang QUAN Liangwei CUI | 2013 | Integrative Zoology2013，8，1： | 0 |
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