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CINRAD-CD调制分机“调制脉冲过流”故障的检查和排除 被引量:8
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作者 李明元 左经纯 《贵州气象》 2006年第3期35-37,共3页
该文介绍了CINRAD-CD调制分机“调制脉冲过流”故障产生的两种类型共6种情况。分析了各种故障情况的检查部位、排除方法及其注意事项。
关键词 CINRAD-CD 调制分机 过流故障 检查 排除
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毕节CINRAD/CD型天气雷达调制系统典型故障分析与处理 被引量:4
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作者 龚雪鹏 罗红 +1 位作者 陈余明 郭江 《气象水文海洋仪器》 2019年第3期106-108,共3页
文章根据毕节CINRAD/CD型天气雷达调制系统动态分压不均并出现畸变,导致雷达系统运行时单路IGBT承受电压过高造成瞬间被击穿的故障案例,结合该型号天气雷达刚性调制分机的内部布局,对此次故障的诊断、处理过程作了详细介绍,最后对IGBT... 文章根据毕节CINRAD/CD型天气雷达调制系统动态分压不均并出现畸变,导致雷达系统运行时单路IGBT承受电压过高造成瞬间被击穿的故障案例,结合该型号天气雷达刚性调制分机的内部布局,对此次故障的诊断、处理过程作了详细介绍,最后对IGBT调制分机的组成和常见故障的判断方法进行了总结,希望能为同型号雷达保障人员提供一些借鉴和参考。 展开更多
关键词 CINRAD/CD雷达 调制分机 IGBT 动态均压
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Mechanisms of Lung Cancer Caused By Cooking Fumes Exposure: A Minor Review 被引量:5
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作者 王春燕 刘立芳 +2 位作者 刘晓丽 陈文俊 何国平 《Chinese Medical Sciences Journal》 CAS CSCD 2017年第3期193-197,共5页
Cooking fumes (CFs) are mixtures of many toxic components, such as aldehydes, heterocyclic amines, polycyclic aromatic hydrocarbons, fat aerosols and particulate matters. CFs exposure has been proven to be associate... Cooking fumes (CFs) are mixtures of many toxic components, such as aldehydes, heterocyclic amines, polycyclic aromatic hydrocarbons, fat aerosols and particulate matters. CFs exposure has been proven to be associated with many diseases. Lung cancer takes the leading place among the diseases being reported caused by CFs exposure. Molecular and biochemical studies have found that CFs exposure may lead to lung cancer by gene damage, formation of reactive oxygen species, blockage of related proteins’ function, and even cell death. However, reviews about the mechanisms of how CFs exposure leads to lung cancer are still lacking. Elucidation of the mechanisms of lung cancer caused by CFs exposure may provide a new insight into the prevention of lung cancer caused by CFs exposure, as well as laying the foundation for the toxicity study of CFs. In this minor review, the mechanisms of how CFs exposure leads to lung cancer were summarized and discussed. 展开更多
关键词 cooking fumes exposure lung cancer toxic mechanisms
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Electrophoresis Analysis on the Protein Expression in Heteromorphic Leaves of Populus euphratica Oliv. 被引量:1
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作者 岳宁 郑彩霞 Cai-xia 《Agricultural Science & Technology》 CAS 2010年第5期41-45,共5页
[Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-D... [Objective] This study was to elucidate the cellular and molecular mechanism of the development of heteromorphic leaves of Populus euphratica Oliv. [Method] By employing SDS-PAGE and 2-demensional electrophoresis (2-DE) techniques,proteins in various heteromorphic leaves from the same adult tree of P. euphratica were isolated and separated to the electrophoresis technique suitable for the separation and analysis of proteins in leaves of P. euphratica tree. [Results] There were significant differences in the expressions of proteins in various heteromorphic leaves of P. euphratica tree. SDS-PAGE pattern showed that bands of proteins with molecular weight of 57.2,13.2,30.2,23.9 and 33.3 kDa were remarkably different. 2-D electrophoresis pattern presented that proteins in leaves of P. euphratica tree mainly belong to acidic proteins distributed at pH value of 5.0-6.5 and with molecular weight of 20-40 kDa; totally 73 different protein spots were observed,of which 51 were up expressed and other 22 were down expressed in the serrated ovate leaves. [Conclusion] Based on these results,we speculate that regulated gene expression in leaves of P. euphratica tree results in the generation of different shapes of leaves,in order to adapt to the surroundings better. 展开更多
关键词 Populus euphratica Oilv. Heteromorphic leaves SDS-PAGE 2-demensional electrophoresis
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A QoS-Aware Packet Scheduling Mechanism in Cognitive Radio Networks for Smart Grid Applications 被引量:1
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作者 XU Siya WEI Lei +3 位作者 LIU Zhu GUO Shaoyong QIU Xuesong MENG Luoming 《China Communications》 SCIE CSCD 2016年第2期68-78,共11页
Cognitive radio sensor network is applied to facilitate network monitoring and management, and achieves high spectrum efficiencies in smart grid. However, the conventional traffic scheduling mechanisms are hard to pro... Cognitive radio sensor network is applied to facilitate network monitoring and management, and achieves high spectrum efficiencies in smart grid. However, the conventional traffic scheduling mechanisms are hard to provide guaranteed quality of service for the secondary users. It is because that they ignore the influence of diverse transition requirements in heterogeneous traffi c. Therefore, a novel Qo S-aware packet scheduling mechanism is proposed to improve transmission quality for secondary users. In this mechanism, a Qo S-based prioritization model is established to address data classification firstly. And then, channel quality and the effect of channel switch are integrated into priority-based packet scheduling mechanism. At last, the simulation is implemented with MATLAB and OPNET. The results show that the proposed scheduling mechanism improves the transmission quality of high-priority secondary users and increase the whole system utilization by 10%. 展开更多
关键词 smart grid cognitive radio sensornetworks (CRSN) quality of service (QoS) scheduling mechanism
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Improved control of intelligent excavator using proportional-integral-plus gain scheduling 被引量:5
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作者 顾军 D. SEWARD 《Journal of Central South University》 SCIE EI CAS 2012年第2期384-392,共9页
Consider the design and implementation of an electro-hydraulic control system for a robotic excavator, namely the Lancaster University computerized and intelligent excavator (LUCIE). The excavator was developed to aut... Consider the design and implementation of an electro-hydraulic control system for a robotic excavator, namely the Lancaster University computerized and intelligent excavator (LUCIE). The excavator was developed to autonomously dig trenches without human intervention. One stumbling block is the achievement of adequate, accurate, quick and smooth movement under automatic control, which is difficult for traditional control algorithm, e.g. PI/PID. A gain scheduling design, based on the true digital proportional-integral-plus (PIP) control methodology, was utilized to regulate the nonlinear joint dynamics. Simulation and initial field tests both demonstrated the feasibility and robustness of proposed technique to the uncertainties of parameters, time delay and load disturbances, with the excavator arm directed along specified trajectories in a smooth, fast and accurate manner. The tracking error magnitudes for oblique straight line and horizontal straight line are less than 20 mm and 50 mm, respectively, while the velocity reaches 9 m/min. 展开更多
关键词 robotic excavator gain scheduling control proportional-integral-plus ROBUSTNESS
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Social Myths: A New Approach
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作者 Gerard Bouchard 《Journal of Philosophy Study》 2016年第6期356-366,共11页
Nowadays, the study of myths is rather neglected as a field of research in sociology. There is a void that this paper would like to contribute to filling. It outlines a theoretical and empirical sociological approach ... Nowadays, the study of myths is rather neglected as a field of research in sociology. There is a void that this paper would like to contribute to filling. It outlines a theoretical and empirical sociological approach to social myths as a major component of collective imaginaries and a universal sociological mechanism through time and space. The article recalls the major functions performed by myths in every society (modem as well as "primitive"), introduces new concepts, and sets forth an analytical framework designed to account for the emergence, the reproduction, and the decline of myths, as sacralised collective representations. 展开更多
关键词 social myths archemyths mythification process discursive strategies
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CLINICAL APPLICATION OF CILIAO IN ACUPUNCTURE TREATMENT
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作者 钱小燕 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1999年第2期126-128,共3页
Ciliao(UB 32),located at the 2ndposterior sacral foramen,is the point of theBladder Meridian.According to the literature,the indications of Ciliao include low back pain,
关键词 Acupuncture Points Acupuncture Therapy ADULT DYSMENORRHEA Female Humans IMPOTENCE Male MOXIBUSTION
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The Coevolutionary Relationship of Technology, Market and Government Regulation in Telecommunications 被引量:1
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作者 Xuchen Lin Ting-Jie Lv Xia Chen 《China Communications》 SCIE CSCD 2018年第8期152-173,共22页
The telecommunications industry has been undergoing tremendous technological changes, and owning to continuous technological advancement, it has maintained sustained prosperity and development. In this paper, the inte... The telecommunications industry has been undergoing tremendous technological changes, and owning to continuous technological advancement, it has maintained sustained prosperity and development. In this paper, the interplay between technology, market and government in telecommunications is discussed briefly, and then we introduce technology and government into the traditional SCP(Structure – Conduct – Performance) paradigm to develop an industry analysis framework called TGM(SCP)(Technology – Government – Market(Structure – Conduct – Performance)). Based on this framework, we present the spiral coevolution model which elaborates on the interaction mechanism of technological innovation with government regulation and market dynamics from the perspective of industry evolution. Our study indicates that the development of the telecommunications industry is the result of the coevolution of technology, government regulation and market forces, and among the three actors, technology is the fundamental driving force. Relative to the "invisible hand"(market) and "visible hand"(government), we conceptualize technology as the "third hand", which fundamentally drives the development of telecommunications industry in coordination with the other two hands. We also provide several policy implications regarding these findings. 展开更多
关键词 technological innovation government regulation telecommunications evolutionary theory
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The modulation recognition based on decision-making mechanism and neural network integrated classifier
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作者 袁海英 Sun Xun Li Haitao 《High Technology Letters》 EI CAS 2013年第2期132-136,共5页
A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time ... A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time domain by the coordinated rotation digital computer(CORDIC) algorithm based on the extended convergence domain and feature parameters of frequency spectrum and power spectrum are extracted by the time-frequency analysis method.All pattern identification parameters are calculated under the I/Q orthogonal two-channel structure,and constructed into the feature vector set.Next,the classifier is designed according to the modulation pattern and recognition performance of the feature parameter set,the optimum threshold is selected for each feature parameter based on the decision-making mechanism in a single classifier,multi-source information fusion and modulation recognition are realized based on feature parameter judge process in the NNIC.Simulation results show NNIC is competent for all modulation recognitions,8 kinds of digital modulated signals are effectively identified,which shows the recognition rate and anti-interference capability at low SNR are improved greatly,the overall recognition rate can reach 100%when SNR is12dB. 展开更多
关键词 modulation recognition decision-making mechanism neural network integratedclassifier (NNIC) feature extraction
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The 5'-flanking cis-acting elements of the human ε-globin gene associates with the nuclear matrix and binds to the nuclear matrix proteins
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作者 YANZHIJIANG RUOLANQIAN 《Cell Research》 SCIE CAS CSCD 1998年第3期209-218,共10页
The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5’-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has ... The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5’-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has been shown that the positive stage-specific regulatory element (ε-PREII, -446bp-419bp) upstream of this gene could specifically associate with the nuclear matrix from K562 cells, indicating thatε-PREII mad be an erythroidspecilic facultstive MAR. In gel mobility shift assay and Southwestern blotting assal an eothroid-specific nuclear matrix protein (ε-NMPk) in K562 cells has been revealed to bind to this positive regulatory element (E-PREII). Furthermore, we demonstrated that the silencer (-392hp -177bp) uP8tream of the humanε-globin gene could associate with the nuclear matrices from K562, HEL and Raji cells. In addition, the nucleax matrix proteins prepared from these three cell lines could also bind to this silencer, suggesting that this silencer element linght be a constitutive nuclear mains attachment region (constitutive MAR). Our results demonstrated that the nucleax madrid and nuclear mains proteins lxilght play an important role in the regulation of the human 5-globin gene expression. 展开更多
关键词 Human ε-globin gene nuclear matrix attachment regions nuclear matrix proteins K562 cells
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Stochastic Differential Game Model for Decentralized Power Control with Wisdom Regulation Factor in Wearable Audio-Oriented BodyNets
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作者 Chen Yueyun Zhang Long Zhou Xianwei 《China Communications》 SCIE CSCD 2012年第12期117-126,共10页
In this study, aiming at the characteristics of randomness and dynamics in Wearable Audiooriented BodyNets (WA-BodyNets), stochastic differential game theory is applied to the investigation of the problem of transm... In this study, aiming at the characteristics of randomness and dynamics in Wearable Audiooriented BodyNets (WA-BodyNets), stochastic differential game theory is applied to the investigation of the problem of transmitted power control inconsumer electronic devices. First, astochastic differential game model is proposed for non-cooperative decentralized uplink power control with a wisdom regulation factor over WA-BodyNets with a onehop star topology.This model aims to minimize the cost associated with the novel payoff function of a player, for which two cost functions are defined: functions of inherent power radiation and accumulated power radiation darmge. Second, the feedback Nash equilibrium solution of the proposed model and the constraint of the Quality of Service (QoS) requirement of the player based on the SIR threshold are derived by solving the Fleming-Bellman-Isaacs partial differential equations. Furthermore, the Markov property of the optimal feedback strategies in this model is verified.The simulation results show that the proposed game model is effective and feasible for controlling the transmitted power of WA-BodyNets. 展开更多
关键词 stochastic differential game body area networks power control wisdom regulation factor
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The size matters: regulation of lipid storage by lipid droplet dynamics 被引量:13
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作者 Jinhai Yu Peng Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第1期46-56,共11页
Adequate energy storage is essential for sustaining healthy life. Lipid droplet (LD) is the subcellular organelle that stores energy in the form of neutral lipids and releases fatty acids under energy deficient cond... Adequate energy storage is essential for sustaining healthy life. Lipid droplet (LD) is the subcellular organelle that stores energy in the form of neutral lipids and releases fatty acids under energy deficient conditions. Energy storage capacity of LDs is primarily dependent on the sizes of LDs. Enlargement and growth of LDs is controlled by two molecular pathways: neutral lipid synthesis and atypical LD fusion. Shrinkage of LDs is mediated by the degradation of neutral lipids under energy demanding conditions and is controlled by neutral cytosolic lipases and lysosomal acidic lipases. In this review, we summarize recent progress regarding the regulatory pathways and molecular mechanisms that control the sizes and the energy storage capacity of LDs. 展开更多
关键词 lipid storage lipid droplet TAG synthesis atypical LD fusion LIPOLYSIS
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Medullary thymic epithelial cells,the indispensable player in central tolerance 被引量:2
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作者 SHI YaoYao ZHU MingZhao 《Science China(Life Sciences)》 SCIE CAS 2013年第5期392-398,共7页
Crosstalk between thymocytes and thymic epithelial cells is critical for T cell development and the establishment of central tolerance.Medullary thymic epithelial cells(mTECs) play important roles in the late stage of... Crosstalk between thymocytes and thymic epithelial cells is critical for T cell development and the establishment of central tolerance.Medullary thymic epithelial cells(mTECs) play important roles in the late stage of T cell development,especially negative selection and Treg generation.The function of mTECs is highly dependent on their characteristic features such as ectopic expression of peripheral tissue restricted antigens(TRAs) and their master regulator-autoimmune regulator(Aire),expression of various chemokines and cytokines.In this review,we summarize the current understanding of cellular and molecular mechanisms of mTEC development and its functions in T cell development and the establishment of central tolerance.The open questions in this field are also discussed.Understanding the function and underlying mechanisms of mTECs will contribute to the better control of autoimmune diseases and the improvement of immune reconstitution during aging or after infection,chemotherapy or radiotherapy. 展开更多
关键词 mTECs T cell development TREG negative selection AUTOIMMUNITY
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Neomycin biosynthesis is regulated positively by AfsA-g and NeoR in Streptomyces fradiae CGMCC 4.7387 被引量:8
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作者 Xiangxi Meng Wenzhao Wang +9 位作者 Zhoujie Xie Pengwei Li Yue Li Zhengyan Guo Yingjian Lu Jie Yang Kaile Guan Zhaoxin Lu Huarong Tan Yihua Chen 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第9期980-991,共12页
Neomycins are a group of aminoglycoside antibiotics with both clinical and agricultural applications.To elucidate the regulatory mechanism of neomycin biosynthesis,we completed draft genome sequencing of a neomycin pr... Neomycins are a group of aminoglycoside antibiotics with both clinical and agricultural applications.To elucidate the regulatory mechanism of neomycin biosynthesis,we completed draft genome sequencing of a neomycin producer Streptomyces fradiae CGMCC 4.7387 from marine sediments,and the neomycin biosynthesis gene cluster was identified.Inactivation of the afsA-g gene encoding a γ-butyrolactone(GBL) synthase in S.fradiae CGMCC 4.7387 resulted in a significant decrease of neomycin production.Quantitative RT-PCR analysis revealed that the transcriptional level of neoR and the aphA-neoGH operon were reduced in the afsA-g::aac(3)Ⅳ mutant.Interestingly,a conserved binding site of AdpA,a key activator in the GBL regulatory cascade,was discovered upstream of neoR,a putative regulatory gene encoding a protein with an ATPase domain and a tetratricopeptide repeat domain.When neoR was inactivated,the neomycin production was reduced about 40%in comparison with the WT strain.Quantitative RT-PCR analysis revealed that the transcriptional levels of genes in the aphA-neoGH operon were reduced clearly in the neoR::aac(3)Ⅳ mutant.Finally,the titers of neomycin were improved considerably by overexpression of qfsA-gand neoR in S.fradiae CGMCC 4.7387. 展开更多
关键词 NEOMYCIN REGULATION Γ-BUTYROLACTONE STREPTOMYCES
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Aquaporin-4 and traumatic brain edema 被引量:10
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作者 徐妙 苏伟 徐秋萍 《Chinese Journal of Traumatology》 CAS 2010年第2期103-110,共8页
Brain edema leading to an expansion of brain volume has a crucial impact on morbidity and mortality following traumatic brain injury as it increases intracranial pressure, impairs cerebral perfusion and oxygenation, a... Brain edema leading to an expansion of brain volume has a crucial impact on morbidity and mortality following traumatic brain injury as it increases intracranial pressure, impairs cerebral perfusion and oxygenation, and contributes to additional ischemic injuries. Classically, two major types of traumatic brain edema exist: "vasogenic" and "cytotoxic/cellular". However, the cellular and molecular mechanisms contributing to the development/resolution of traumatic brain edema are poorly understood and no effective drugs can be used now. Aquaporin-4 (AQP4) is a water-channel protein expressed strongly in the brain, predominantly in astrocyte foot processes at the borders between the brain parenchyma and major fluid compartments,including cerebrospinal fluid and blood. This distribution suggests that AQP4 controls water fluxes into and out of the brain parenchyma. In cytotoxic edema, AQP4 deletion slows the rate of water entry into brain, whereas in vasogenic edema, AQP4 deletion reduces the rate of water outflow from brain parenchyma. AQP4 has been proposed as a novel drug target in brain edema. These findings suggest that modulation of AQP4 expression or function may be beneficial in traumatic brain edema. 展开更多
关键词 BRAIN EDEMA Wounds and injuries AQUAPORINS
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Cell biology and immunology lessons taught by Legionella pneumophila
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作者 Wenhan Zhu Zhao-Qing Luo 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第1期3-10,共8页
Legionella pneumophila is a facultative intracellular pathogen capable of replicating within a broad range of hosts. One unique feature of this pathogen is the cohort of ca. 300 virulence factors(effectors) delivered ... Legionella pneumophila is a facultative intracellular pathogen capable of replicating within a broad range of hosts. One unique feature of this pathogen is the cohort of ca. 300 virulence factors(effectors) delivered into host cells via its Dot/Icm type IV secretion system. Study of these proteins has produced novel insights into the mechanisms of host function modulation by pathogens, the regulation of essential processes of eukaryotic cells and of immunosurveillance. In this review, we will briefly discuss the roles of some of these effectors in the creation of a niche permissive for bacterial replication in phagocytes and recent advancements in the dissection of the innate immune detection mechanisms by challenging immune cells with L. pneumophila. 展开更多
关键词 Type IV secretion INFLAMMASOME EFFECTORS posttranslational modification vesicle transport
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