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Characteristics of long period microtremor and validation of microtremor array measurements in inland areas of China

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Journal of Mountain Science 2016年第11期13卷 1910-1922页

作者： CHE Ai-lan ZHANG Teng-yu feng shao-kong School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University 800 Dongchuan-Road Shanghai 200240 China

To study the characteristics of long period microtremor and applicability of microtremor survey,we have made microtremor observations using long period seismometers of the China's mainland from coastal cities like Shanghai and Tianjin through Beijing,Xi'an,to the far inland cities of Lanzhou and *** observation shows that the level of power spectrum of long period microtremors reduced rapidly from the coast to the inland ***,the energy of long period microtremors in Beijing,Xi'an,Lanzhou and Tianshui area are only approximately ten-thousandth to thousandth of that in *** at the complexity of the underground structure in the far inland,a series of underground structure models with different distributions were assessed using three-dimensional,dynamic finite element method(FEM) *** results were used to evaluate microtremor survey methods and their limitations with regard to aggregate variability and thickness ***-wave reflections between layers with the change of underground structure distribution occurred,which have significant effect on the performance of the different field *** over a broad spectrum from which velocity-depth profiles were produced via inversion *** the thickness nor the shear waveVelocity V of the subsurface layer inversion results appeared over a large evaluation with increasing slope *** particular,when the angle of the model reached 45°,it could not be accurately evaluated using one-dimensional inversion ***,the array microtremor survey(AMS) was carried out in Shanghai City,*** AMS techniques do not have the layer sensitivity or accuracy(velocity and layer thickness) of borehole techniques,the obtained shear wave velocity structure is especially useful for earthquake disaster prevention and seismic analysis.

关键词： Long period microtremor Array Microtremor survey Power spectrum Inversion S-wave velocity structure

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Paraventricular Thalamus as A Major Thalamic Structure for Wake Control

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Neuroscience Bulletin 2019年第5期35卷 946-948页

作者： yu-feng shao Jian-Sheng Lin Yi-Ping Hou Departments of Neuroscience Anatomy Histology and Embryology Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences Lanzhou University Lanzhou 730000 China Integrative Physiology of the Brain Arousal Systems Lyon Neuroscience Research Center Lyon 69373 France

The thalamus is the gate of the cerebral cortex, the ultimate target for the neural networks controlling behavioral states and cognitive functions. According to the reticular theory initially proposed by Moruzzi and Magoun, excitatory inputs from large reticular zones of the brainstem via widespread intra- and extra-thalamocortical systems finally activate the cerebral cortex to cause generalized cortical activation and wakefulness [1]. This theory proposes a central relay role to the thalamus for cortical activation as supported by early studies using neurodegeneration techniques and by the elegant work of Steriade’s group and other investigators illustrating the electrophysiological mechanisms of the thalamocortical system at the cellular level during wakefulness, rapid eye-movement sleep (REMs) and non-REM sleep (NREMs)[2].

关键词： Paraventricular Thalamus Thalamic Structure Wake Control

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Pre-reinforcement grout in fractured rock masses and numerical simulation for optimizing shrinkage stoping configuration

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Journal of Central South University 2017年第12期24卷 2924-2931页

作者： yu shao-feng WU Ai-xiang WANG Yi-ming LI Tao School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of High-Efficient Mining and Safety of Metal of Ministry of Education University of Science and Technology Beijing Beijing 100083 China

Proper room and pillar sizes are both critical factors for safe mining and high ore recovery rate in shrinkage stoping mining of underground metal mines. The rock masses of Tangdan copper mine of China are fractured, which needs much reinforcement and support prior to mining. Cement-sodium silicate grout technology was selected, then its related parameters such as grout pressure, diffusion radius and time were calculated and proposed. In order to test the effect of the pressured grout in the fractured No.4 ore block, field experiments were conducted. To optimize stoping configuration, three-dimensional numerical simulation with ANSYS and FLAC 3 D softwares was proposed. The results show that the drilling porosity and mechanical properties of the rock masses are increased obviously. After grout, ore recovery rate is increased by 10.2 % employing the newly designed stoping configuration compared with the previous. Last, analyzed from the surface movements, roof subsidence and the maximum principal stress of the pillars, the mining safety is probable of being ensured.

关键词： shrinkage stoping mining cement-sodium silicate grout effect of pressured grout stoping configuration three-dimensional numerical simulation

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Synthesis of a New Asymmetrical Ether Diamine with Aromatic Structure and Related Polyimide

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Chinese Chemical Letters 2006年第5期17卷 635-636页

作者： yu shao Yah feng LI Xiao Long WANG Shu Jiang ZHAN Xin ZHAO Tao MA State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl ether segments was prepared from the resulting diamine with 4,4＇-oxydiphthalic anhydride （ODPA） via a conventional two-step thermal or chemical imidization method. The resulting polyimide exhibits high thermal resistance, excellent solubility, film-forming capability, high mechanical strength and modulus.

关键词： Polyimide asymmetrical ether diamine aromatic polyimide.

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Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing

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Chinese Physics B 2024年第5期33卷 758-763页

作者：严浩然颜家琦俞连春邵玉峰 School of Physical Science and Technology Lanzhou Center for Theoretical PhysicsLanzhou UniversityLanzhou 730000China Key Laboratory of Theoretical Physics of Gansu Province and Key Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China Department of Neuroscience AnatomyHistologyand EmbryologyKey Laboratory of Preclinical Study for New Drugs of Gansu ProvinceSchool of Basic Medical SciencesLanzhou UniversityLanzhou 730000China

The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological *** raises the problem why neurons would favor independent over cooperative channel *** this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy *** of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy *** a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information *** discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases.

关键词： energy efficiency ion channel noise action potential generation neuronal dynamics

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Water Security Problem in North China: Research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-yu JIA shao-feng Key Laboratory of Water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State Key Laboratory of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072（China） Center for Agricultural Resources Research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North China with the aim of highlighting key waterresources management and water security issues for the long-term development of North China. Three key problemsrelated to water resources and security issues in North China in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North China are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth China farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North China’s water security.

关键词： environmental change North China water cycle water resources water security

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Optimization,validation and application of an assay for the activity of HMG-CoA reductase in vitro by LC–MS/MS

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Journal of Pharmaceutical Analysis 2015年第6期5卷 383-388页

作者： Jing Wang Ji-Ye Sun Chun-Jie Sha yu-feng shao Yan-Hong Liu You-Xin Li Zhen-Wen Duan Wan-Hui Liu School of Pharmacy Yantai University State Key Laboratory of Long-acting and Targeting Drug Delivery System Shandong Luye Pharmaceutical Co. Ltd. Peking University WBL Biotech Co. Ltd.

A stable HMG-CoA reductase （HMGR） reaction in vitro was developed by a sensitive, selective and precise liquid chromatography-tandem mass spectrometry （LC-MS/MS） method. The optimized enzyme reaction condition contained 1.5 lag of HMGR, 20 nM of NADPH with 50 rain of reaction time. The method was validated by several intraand inter-day assays. The production transitions of m/z 147.0/59.1 and m/z 154.0/59.1 were used to detect and quantify mevalonolactone （MVAL） and MVAL-DT, respectively. The accuracy and precision of the method were evaluated over the concentration range of 0.005- 1.000 lag/mL for MVAL and 0.010-0.500 lag/mL for lovastatin acid in three validation batch runs. The lower limit of quantitation was found to be 0.005 lag/mL for MVAL and 0.010 lag/mL for lovastatin acid. Intra-day and inter-day precision ranged from 0.95% to 2.39% and 2.26% to 3.38% for MVAL, 1.46% to 3.89% and 0.57% to 5.10% for lovastatin acid, respectively. The results showed that the active ingredients in Xuezhikang capsules were 12.2 and 14.5 mg/g, respectively. This assay method could be successfully anDlied to the oualitv control study of Xuezhikanu caosule for the first time.

关键词： XuezhikangLC-MS/MSHMG-CoA reductaseMevalonolactoneQuality control

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高机动三坐标雷达比幅测高误差分析及修正

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现代雷达 2007年第4期29卷 79-81页

作者：邵余峰南京电子技术研究所南京210013

讨论了比幅测高的基本原理,分析了影响比幅测高精度的各种因素。定量计算了由这些因素引起的误差量。并提出了一种简单易行的修正方法,即根据一次雷达的测高值和二次雷达的测高值计算出天线波束指向的调整量,对天线阵面波束指向进行微调... 详细信息

讨论了比幅测高的基本原理,分析了影响比幅测高精度的各种因素。定量计算了由这些因素引起的误差量。并提出了一种简单易行的修正方法,即根据一次雷达的测高值和二次雷达的测高值计算出天线波束指向的调整量,对天线阵面波束指向进行微调,从而提高了测高精度。由于对天线波束指向的调整在很小的范围内,故对天线的副瓣及波瓣宽度指标的影响可忽略,从而不会影响到雷达系统的其他性能。

关键词：三坐标雷达波束指向比幅测高测高精度

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Novel transmitter of dark RZ signal based on external modulator

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Optoelectronics Letters 2007年第2期3卷 109页

作者： yu-feng, shao Chen, Lin Shuang-chun, Wen Hunan University School of Computer and Communication Changsha China (GRID:grid.67293.39)

A novel transmitter to generate a dark RZ signal with tunable duty cycle and extinction ratio is proposed, by modifying the process of precoding, modulating and coding. A dark RZ signal is generated simply by using one dual-arm Mach-Zehnder LiNbO3 modulator. We demonstrate experimentally that this optical dark RZ signal can be directly measured by a conventional binary intensity modulation direct detection (IM-DD) receiver. When different values of duty cycles at 2.5 Gbit/s are adjusted, the experimental results show different BER curves and eye diagrams of the optical dark RZ signal.

关键词： intensity modulation extinction ratio direct detection duty cycle

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Role of neuropeptide S in sleep-wake regulation

Role of neuropeptide S in sleep-wake regulation

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中国神经科学学会第十届全国学术会议

作者： Yi-Ping HOU Peng ZHAO yu-feng shao Xiang-Pan KONG Department of Neuroscience AnatomyHistology and EmbryologyKey Laboratory of Preclinical Study for New Drugs of Gansu ProvinceSchool of Basic Medical SciencesLanzhou University

Objective Neuropeptide S（NPS） is a newly identified neuromodulator located in the *** selectively binds with high affinity to its receptor（NPSR）,involving in the regulation of multiple central *** NPS-NPSR system is proposed as a new arousal ***,the effects of NPS on the architectures of sleep-waking states and the mechanisms involved remain *** study is to explore the effects and mechanisms of NPS-NPSR system on sleep-wake *** Firstly,the sleep-waking states and related EEG power spectra were defined by the electroencephalogram（EEG） and electromyogram（EMG） signal recordings during light-phrase（8:00-20:00 h） in freely moving rats following intracerebroventricular（i.c.v.） injection of NPS,and ex-vivo Fos immunohistochemistry was made to identify the potential neuronal targets for NPS in the brain involved in ***,according to primary results,the distribution of NPSR mRNA was revealed by quantitative real-time PCR（RT-PCR） and dual-immunofluorescences *** sleep-waking profiles following bilateral microinjections of NPS into the tuberomammillary nucleus（TMN） were studied for comprehensive understanding NPS-NPSR system in regulating sleep-wake ***,the neuropharmacology assays were made to identify whether the antagonists of NPSR,H1R and H2R receptors block the arousal effect of ***（1） Central administration of NPS（0.1-1 nmol）increased significantly wakefulness（W） during the first 2 h,accompanied by an increase in EEG high frequency activities（14.5-60 Hz）.In the meanwhile,slow wave sleep（SWS） and paradoxical sleep（PS） decreased significantly,and accompanied by a suppression in EEG delta（0.5-4 Hz） and theta（4.5-8.5 Hz） *** W-increasing effect was because of a significant increase in the mean duration of wake episode.（2） Fos immunohistochemistry in the posterior hypothalamus revealed that,as compared with saline-treated rats,NPS enhanced c-Fos expression in histaminergic n

关键词： neuropeptide S neuropeptide S receptor sleep-wake states tuberomammillary nucleus histaminergic neurons orexinergic neurons histamine receptor antagonist

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