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Pulse shaping of bright-dark vector soliton pair
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作者 周延 李月锋 +3 位作者 李夏 廖梅松 侯京山 房永征 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期235-242,共8页
We simulate pulse shaping of bright-dark vector soliton pair in an optical fiber system.Through changing input pulse parameters(amplitude ratio,projection angle,time delay,and phase difference),different kinds of puls... We simulate pulse shaping of bright-dark vector soliton pair in an optical fiber system.Through changing input pulse parameters(amplitude ratio,projection angle,time delay,and phase difference),different kinds of pulse shapes and spectra can be generated.For input bright-dark vector soliton pair with the same central wavelength,“2+1”-and“2+2”-type pseudo-high-order bright-dark vector soliton pairs are achieved.While for the case of different central wavelengths,bright-dark vector soliton pairs with multiple pulse peaks/dips are demonstrated with appropriate pulse parameter setting. 展开更多
关键词 bright-dark vector soliton birefringence polarization-locking group-velocity-locking
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太阳紫外辐照度影响东亚冬季气候的研究进展 被引量:1
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作者 钟琦 李跃凤 +2 位作者 赵亮 董仕 胡宜昌 《地球科学前沿(汉斯)》 2018年第2期422-430,共9页
特定区域气候系统对太阳分光谱辐射的响应和放大机制是当代气候和气候变化研究的热点科学问题之一。本文聚焦太阳紫外辐射和东亚地区,阐述近年来太阳紫外辐射的卫星观测和数据重建进展,总结太阳紫外辐射影响东亚冬季气候的途径和关键环... 特定区域气候系统对太阳分光谱辐射的响应和放大机制是当代气候和气候变化研究的热点科学问题之一。本文聚焦太阳紫外辐射和东亚地区,阐述近年来太阳紫外辐射的卫星观测和数据重建进展,总结太阳紫外辐射影响东亚冬季气候的途径和关键环节,即太阳紫外辐射直接作用于平流层臭氧,通过改变臭氧分布影响平流层大气的温度和环流场,进而通过平流层–对流层的耦合作用将太阳活动信号向对流层和极地传播,并通过调制北极涛动等大气遥相关型的位相影响东亚大气环流,实现对东亚冬季气候的间接作用。目前的研究认为太阳紫外辐射增强(减弱)常易激发正位相(负位相)北极涛动,对应东亚冬季暖冬(寒潮低温)。最后,展望了该领域未来的研究重点,即基于大气–海洋–化学耦合的气候系统模式开展太阳紫外辐射影响东亚冬季气候的量化评估和研究。 展开更多
关键词 太阳紫外辐射 东亚 冬季气候 北极涛动 平流层-对流层相互作用
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Study of the relationship between sphenoid sinus volume and protrusions in the sphenoid sinus
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作者 yuefeng li Jiaqi Sun +4 位作者 Xiwen Zhu Chenhao Zhao Jin Xu Ping Jiang Xinkang Tong 《Forensic Medicine and Anatomy Research》 2014年第1期2-7,共6页
The relationship between the volume of sphenoid sinus (SS) and the prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusions in the SS was studied by using high-resolution CT imaging. The ICA and ON... The relationship between the volume of sphenoid sinus (SS) and the prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusions in the SS was studied by using high-resolution CT imaging. The ICA and ON protrusions in SS were observed in randomly selected normal head CT scanning images from 350 adult subjects. Ac-cording to the incidence of ICA protrusion, three groups were divided into no ICA protrusion (70.75%), unilateral protrusion (8.68%) and bi-lateral protrusions (20.57%). The ON protrusion accounted for 16% in 350 subjects and accom-panied absolutely with ICA protrusion, but ICA protrusion appeared without accompanying with ON protrusion. The SS volume depended upon the protrusions in it and showed statistical dif-ferences, without ICA protrusion, the smallest size (11.16 ± 1.60) cm3;the unilateral protrusion, medium size (14.20 ± 1.80) cm3 and the bilateral protrusion, the largest size (25.03 ± 2.21) cm3. By observing 3D reconstructed models of ON and SS, we found ON was adjacent to SS (46%) and to posterior ethmoid sinuses (44%). The current study indicates that SS volume is varied with numbers of the protrusions and that ON location varies with the pneumatization of SS. Our results provide an anatomical basis to the surgeries for SS and its surrounding structures. 展开更多
关键词 SPHENOID SINUS VOLUME PROTRUSION of Internal CAROTID ARTERY CT Imaging
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Discovery of a highly specific ^(18)F-labeled PET ligand for phosphodiesterase 10A enabled by novel spirocyclic iodonium ylide radiofluorination
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作者 Zhiwei Xiao Huiyi Wei +19 位作者 Yi Xu Ahmed Haider Junjie Wei Shiyu Yuan Jian Rong Chunyu Zhao Guocong li Weibin Zhang Huangcan Chen yuefeng li lingling Zhang Jiyun Sun Shaojuan Zhang Hai-Bin Luo Sen Yan Qijun Cai Lu Hou Chao Che Steven H.liang Lu Wang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第4期1963-1975,共13页
As a member of cyclic nucleotide phosphodiesterase(PDE)enzyme family,PDE10A is in charge of the degradation of cyclic adenosine(cAMP)and guanosine monophosphates(cGMP).While PDE10A is primarily expressed in the medium... As a member of cyclic nucleotide phosphodiesterase(PDE)enzyme family,PDE10A is in charge of the degradation of cyclic adenosine(cAMP)and guanosine monophosphates(cGMP).While PDE10A is primarily expressed in the medium spiny neurons of the striatum,it has been implicated in a variety of neurological disorders.Indeed,inhibition of PDE10A has proven to be of potential use for the treatment of central nervous system(CNS)pathologies caused by dysfunction of the basal ganglia–of which the striatum constitutes the largest component.A PDE10A-targeted positron emission tomography(PET)radioligand would enable a better assessment of the pathophysiologic role of PDE10A,as well as confirm the relationship between target occupancy and administrated dose of a given drug candidate,thus accelerating the development of effective PDE10A inhibitors.In this study,we designed and synthesized a novel ^(18)F-aryl PDE10A PET radioligand,codenamed[^(18)F]P10A-1910([^(18)F]9),in high radiochemical yield and molar activity via spirocyclic iodonium ylide-mediated radiofluorination.[^(18)F]9 possessed good in vitro binding affinity(IC_(50)=2.1 nmol/L)and selectivity towards PDE10A.Further,[^(18)F]9 exhibited reasonable lipophilicity(logD=3.50)and brain permeability(P_(app)>10×10^(−6) cm/s in MDCK-MDR1 cells).PET imaging studies of[^(18)F]9 revealed high striatal uptake and excellent in vivo specificity with reversible tracer kinetics.Preclinical studies in rodents revealed an improved plasma and brain stability of[^(18)F]9 when compared to the current reference standard for PDE10A-targeted PET,[^(18)F]MNI659.Further,dose–response experiments with a series of escalating doses of PDE10A inhibitor 1 in rhesus monkey brains confirmed the utility of[^(18)F]9 for evaluating target occupancy in vivo in higher species.In conclusion,our results indicated that[^(18)F]9 is a promising PDE10A PET radioligand for clinical translation. 展开更多
关键词 Phosphodiesterase 10A PET radioligand 18F Spirocyclic iodonium ylide Nonhuman primate Target occupancy
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Interannual variations in length of day and atmospheric angular momentum, and their seasonal associations with El Ni^o/Southern Oscillation-like sea surface temperature patterns
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作者 yuefeng li Ziniu XIAO +3 位作者 Wenjing SHI Qi ZHONG Qiguang WANG Huanlian li 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2017年第4期751-764,共14页
This study examines the seasonal connections between the interannual variations in LOD (length of day)/ AAMglobe (the relative atmospheric angular momentum for the whole globe) and the ENSO-like SST (El Nifio/ So... This study examines the seasonal connections between the interannual variations in LOD (length of day)/ AAMglobe (the relative atmospheric angular momentum for the whole globe) and the ENSO-like SST (El Nifio/ Southern Oscillation-like sea surface temperature) pattern and corresponding zonal and vertical circulations. Consistent with previous studies, the ENSO-like SST impact the following season LOD/AAMglobe, with the strongest correlations in DJF (December, January, and February), when it is likely to be the peak E1 Nino/La Nifia period. Lag correlations between the interannual variations in LOD/AAMglobe and surface temperature, and the interannual variations in LOD and both zonal circulation and vertical airflow around the equator, consistently indicate that the LOD/AAMglobe reflect the potential impacts of variations in the Earth's rotation rate on the following season's sea surface temperatures (SST) over the tropical central and eastern pattern is located). Pacific (where the ENSO-like SST Moreover, the centers of strongest variation in the AAMcolumn (the relative atmospheric angular momentum for an air column and the unit mass over a square meter) are located over the mid-latitudinal North Pacific in DJF and MAM (March, April, and May), and over the mid-latitudinal South Pacific in JJA (June, July, and August) and SON (September, October, and November). This suggests that the AAMcolumn over the mid-latitudinal Pacific around 30°N (30~S) dominate the modulation of Earth's rotation rate, and then impact the variations in LOD during DJF and MAM (JJA and SON). 展开更多
关键词 four season features interannual variation length of day atmospheric angular momentum ENSO-likeSST pattern
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Effect of Sini San Freeze-dried powder on sleep-waking cycle in insomnia rats 被引量:4
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作者 Xingke Yan Zeguo Zhang +4 位作者 Fuju Xu yuefeng li Tiantian Zhu Chongbing Ma Anguo liu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第5期572-575,共4页
OBJECTIVE: To investigate the effects of the Sini San at different doses on each sleeping state[slow-wave sleep 1(SWS1), slow-wave sleep 2(SWS2), rapid-eye-movement(REM), wakefulness(W)] in insomnia rats and to identi... OBJECTIVE: To investigate the effects of the Sini San at different doses on each sleeping state[slow-wave sleep 1(SWS1), slow-wave sleep 2(SWS2), rapid-eye-movement(REM), wakefulness(W)] in insomnia rats and to identify its mode of ac-tion for improving sleep.METHODS: The insomnia rats were randomly divided into a high-, medium- or low-dose group of Sini San(equal to crude drug 8.8, 4.4, or 2.2 g/kg, respectively) for seven consecutive days.RESULTS: Compared with pre-administration,SWS2 was significantly increased after administration of the low dose. Compared with pre-administration, W was significantly decreased and SWS1,SWS2, and the total sleeping time(TST) were markedly increased after administration of the medium dose. Compared with pre-administration, W was significantly decreased and SWS1, SWS2, rapid-eye-movement sleep, and TST were significantly longer after administration of the high dose. The effects of Sini San on sleep-wake cycle are dose-dependent.CONCLUSION: The results suggest that Sini San extends SWS1 and SWS2, which increases the total sleeping time. 展开更多
关键词 睡眠状态 四逆散 大鼠 周期 冻干粉 慢波睡眠 睡眠时间 低剂量
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Sedative and hypnotic effect of freeze-dried paeoniflorin and Sini San freeze-dried powder in pentobarbital sodium-induced mice 被引量:3
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作者 yuefeng li Pingan Wu +4 位作者 Yanmei Ning Xingke Yan Tiantian Zhu Chongbing Ma Anguo liu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第2期184-187,共4页
OBJECTIVE: To investigate the sedative and hypnotic activity of paeoniflorin and freeze-dried Sini San powder on mice and provide a reliable method for determining the pharmacodynamic material basis of Sini San.METHOD... OBJECTIVE: To investigate the sedative and hypnotic activity of paeoniflorin and freeze-dried Sini San powder on mice and provide a reliable method for determining the pharmacodynamic material basis of Sini San.METHODS: Male adult mice weighing 20-22 g were used in this study. Three experiments were carried out. Synergism with pentobarbital was used as an index for hypnotic effect. Loss of the righting reflex was used to determine the start of sleep.Sleep latency and sleeping time were recorded in each experiment.RESULTS: The coefficient of variation of the suprathreshold dose(55 mg/kg) was significantly lower than that of the threshold dose. The sleep latency of mice was significantly decreased, and the sleeping time of mice was significantly prolonged. The effects of paeoniflorin and Sini San on prolonging the sleeping time of mice induced by pentobarbital sodium were significantly stronger than those in the control group.CONCLUSION: Paeoniflorin produces significant sedative and hypnotic effects, and there is an obvious dose-effect relationship. 展开更多
关键词 戊巴比妥钠 成年小鼠 芍药苷 四逆散 镇静剂 冻干粉 催眠 冷冻干燥
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The behaviors of ultra-low-gold-loaded catalysts (Au/ Ce02) for CO oxidation in the presence of water on the catalysts 被引量:2
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作者 Qiaoling li Wei Xie +3 位作者 Guoqin Chen yuefeng li Yanjun Huang Xiaodong Chen 《Nano Research》 SCIE EI CAS CSCD 2015年第9期3075-3084,共10页
The catalytic behavior of ultra-low-gold-loaded Au/CeO2 during CO oxidation was studied using HRTEM, TGA, in-situ FTIR, CO--TPD, O2-TPD, and O2-TPO. Herein, water, which facilitates CO oxidation, is present on the cat... The catalytic behavior of ultra-low-gold-loaded Au/CeO2 during CO oxidation was studied using HRTEM, TGA, in-situ FTIR, CO--TPD, O2-TPD, and O2-TPO. Herein, water, which facilitates CO oxidation, is present on the catalyst rather than obtained from the reactant gas. The experimental results show that the presence of water on the catalyst enhances the adsorption and activation of 02 to produce Oact on the catalyst surface, resulting in excellent catalytic activity. Different reaction pathways for CO oxidation over Au/CeO2 may be present; however, the dominant pathway is influenced by the species on the catalyst surface. 展开更多
关键词 ultra-low-gold catalysts water addition on thecatalysts hydroxyl and carbonate-like species reaction pathways
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