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Chinese Journal of Cancer 2011年第3期30卷 153-162页

作者： Andrea J. McKinney Sheri L. Holmen Department of Drug and target discovery Nevada Cancer Institute

The increasing incidence and mortality associated with advanced stages of melanoma are cause for concern. Few treatment options are available for advanced melanoma and the 5-year survival rate is less than 15%. targeted therapies may revolutionize melanoma treatment by providing less toxic and more effective strategies. However, maximizing effectiveness requires further understanding of the molecular alterations that drive tumor formation, progression, and maintenance, as well as elucidating the mechanisms of resistance. Several different genetic alterations identified in human melanoma have been recapitulated in mice. This review outlines recent progress made in the development of mouse models of melanoma and summarizes what these findings reveal about the human disease. We begin with a discussion of traditional models and conclude with the recently developed RCAS/TVA somatic cell gene delivery mouse model of melanoma.

关键词：黑色素瘤小鼠模型基因传递人类疾病体细胞快速评估动物模型治疗方案

Joint resource allocation scheme for target tracking in distributed MIMO radar systems

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Journal of Systems Engineering and Electronics 2019年第4期30卷 709-719页

作者： ZHENG Na’e SUN Yang SONG Xiyu CHEN Song Data and target Engineering institute PLA Strategic Support Force Information Engineering University

A joint resource allocation scheme concerned with the sensor subset,power and bandwidth for range-only target tracking in multiple-input multiple-output(MIMO)radar systems is *** selecting an optimal subset of sensors with the predetermined size and implementing the power allocation and bandwidth strategies among them,this algorithm can help achieving a better performance within the same resource ***,the Bayesian Cramer-Rao bound(BCRB)is derived from ***,a criterion for minimizing the BCRB at the target location among all targets tracking in a certain range is ***,the optimization problem involved with three variable vectors is formulated,which can be simplified by deriving the relationship between the optimal power allocation vector and the bandwidth allocation ***,the simplified optimization problem is solved by the cyclic minimization algorithm incorporated with the sequential parametric convex approximation(SPCA)***,the validity of the proposed method is demonstrated with simulation results.

关键词： distributed multiple-input multiple-output(MIMO)radar target tracking joint resource alloction sensor subset selection(SSS) optimal power and bandwidth allocation(OPBA)

Calculations of radioactivity and afterheat in the components of the CSNS target station

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Chinese Physics B 2009年第9期18卷 3815-3818页

作者：于全芝梁天骄殷雯严启伟贾学军王芳卫 CSNS Engineering Center for target Station and Instruments Institute of PhysicsChinese Academy of Sciences

This paper shows the calculations of radioactivity and afterheat in the components of the China Spallation Neutron Source （CSNS） target station, with the Monte Carlo codes LAHET, MCNP4C and the multigroup code CINDER＇90. These calculations provide essential data for the detailed design and maintenance of the CSNS target station.

关键词： Monte Carlo codes radioactivity afterheat CSNS target station

Moving target localization for multistatic passive radar using delay, Doppler and Doppler rate measurements

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Journal of Systems Engineering and Electronics 2020年第5期31卷 939-949页

作者： ZHAO Yongsheng HU Dexiu ZHAO Yongjun LIU Zhixin Data and target Engineering institute PLA Strategic Support Force Information Engineering UniversityZhengzhou 450001China

Time delay and Doppler shift between the echo signal and the reference signal are two most commonly used measurements in target localization for the passive radar. Doppler rate, which can be obtained from the extended cross ambiguity function, offers an opportunity to further enhance the localization accuracy. This paper considers using the measurement Doppler rate in addition to measurements of time delay and Doppler shift to locate a moving target. A closed-form solution is developed to accurately and efficiently estimate the target position and *** proposed solution establishes a pseudolinear set of equations by introducing some additional variables, imposes weighted least squares formulation to yield a rough estimate, and utilizes the function relation among the target location parameters and additional variables to improve the estimation accuracy. Theoretical covariance and Cramer-Rao lower bound(CRLB) are derived and compared, analytically indicating that the proposed solution attains the CRLB. Numerical simulations corroborate this analysis and demonstrate that the proposed solution outperforms existing methods.

关键词： target localization multistatic passive radar time delay Doppler shift Doppler rate

Constrained auxiliary particle filtering for bearings-only maneuvering target tracking

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Journal of Systems Engineering and Electronics 2019年第4期30卷 684-695页

作者： ZHANG Hongwei XIE Weixin Automatic target Recognition Key Laboratory Shenzhen University

To track the nonlinear,non-Gaussian bearings-only maneuvering target accurately online,the constrained auxiliary particle filtering(CAPF)algorithm is *** restrict the samples into the feasible area,the soft measurement constraints are implemented into the update routine via the1 ***,to enhance the sampling diversity and efficiency,the target kinetic features and the latest observations are involved into the *** take advantage of the past and the current measurement information simultaneously,the sub-optimal importance distribution is constructed as a Gaussian mixture consisting of the original and modified priors with the fuzzy weighted *** a result,the corresponding weights are more evenly distributed,and the posterior distribution of interest is approximated well with a heavier *** results demonstrate the validity and superiority of the CAPF algorithm in terms of efficiency and robustness.

关键词： bearings-only maneuvering target tracking soft measurement constraints constrained auxiliary particle filtering(CAPF)

Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing Qiu Mengting Yang Danfeng Gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels

Maneuvering target track-before-detect via multiple-model Bernoulli particle filter

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Journal of Central South University 2015年第10期22卷 3935-3945页

作者：占荣辉刘盛启胡杰民张军 Science and Technology on Automatic target Recognition Laboratory National University of Defense Technology

target tracking using non-threshold raw data with low signal-to-noise ratio is a very difficult task, and the model uncertainty introduced by target's maneuver makes it even more challenging. In this work, a multiple-model based method was proposed to tackle such issues. The method was developed in the framework of Bernoulli filter by integrating the model probability parameter and implemented via sequential Monte Carlo(particle) technique. target detection was accomplished through the estimation of target's existence probability, and the estimate of target state was obtained by combining the outputs of modeldependent filtering. The simulation results show that the proposed method performs better than the TBD method implemented by the conventional multiple-model particle filter.

关键词： Bernoulli filter multiple model target maneuver track-before-detect(TBD) sequential Monte Carlo(SMC) technique

SMC-PHD based multi-target track-before-detect with nonstandard point observations model

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Journal of Central South University 2015年第1期22卷 232-240页

作者：占荣辉高彦钊胡杰民张军 Science and Technology on Automatic target Recognition Laboratory National University of Defense Technology

Detection and tracking of multi-target with unknown and varying number is a challenging issue, especially under the condition of low signal-to-noise ratio(SNR). A modified multi-target track-before-detect(TBD) method was proposed to tackle this issue using a nonstandard point observation model. The method was developed from sequential Monte Carlo(SMC)-based probability hypothesis density(PHD) filter, and it was implemented by modifying the original calculation in update weights of the particles and by adopting an adaptive particle sampling strategy. To efficiently execute the SMC-PHD based TBD method, a fast implementation approach was also presented by partitioning the particles into multiple subsets according to their position coordinates in 2D resolution cells of the sensor. Simulation results show the effectiveness of the proposed method for time-varying multi-target tracking using raw observation data.

关键词： adaptive particle sampling multi-target track-before-detect probability hypothesis density(PHD) filter sequential Monte Carlo(SMC) method

Bistatic weak target detection method using non-cooperative air surveillance radar

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Journal of Systems Engineering and Electronics 2015年第5期26卷 954-963页

作者： Dinghe Wang Qinglong Bao Ruiqi Tian Zengping Chen Science and Technology on Automatic target Recognition Laboratory National University of Defense Technology

At present, most of the passive radar system researches utilize FM radios, TV broadcasts, navigation satellites,etc. as illuminators. The transmitted signals are not specifically designed radar waveforms. In this work, the frequency agile, phased array air surveillance radar(ASR) is used as the illuminator of opportunity to detect the weak target. The phased array technology can help realize beam agility to track targets from different aspects simultaneously. The frequency agility technology is widely employed in radar system design to increase the ability of anti-jamming and increase the detection probability. While the frequency bandwidth of radar signals is usually wide and the range resolution is high, the range cell migration effect is obvious during the long time integration of non-cooperative bistatic radar. In this context, coherent integration methods are not applicable. In this work, a parametric non-coherent integration algorithm based on task de-interweaving is proposed. Numerical experiments verify that this is effective in weak target detection.

关键词： air surveillance radar non-cooperative bistatic task de-interweave

Dual Space SVDD Based Radar target Recognition from HRRP

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Chinese Journal of Electronics 2014年第2期23卷 419-425页

作者： XIAO Huaitie FENG Guoyu ZHU Yongfeng HUANG Mengjun Science and Technology on Automatic target Recognition Laboratory National University of Defense Technology

In radar target recognition based on kernel method, Support vector data description(SVDD) has been applied to High resolution range profiles(HRRPs)recognition. In this paper, first, three distribution models,i.e., Membership model, Cloud model, Gaussian mixture model, are developed to describe distribution characteristics of HRRPs in extended space. Secondly, test HRRPs in multi-target hypersphere spaces are classified, in accordance with their multi-space distributing characteristics,into two types, i.e., shrink sample and slack sample. Determination of the property of a test sample is achieved by using the minimum relative distance for shrink samples and three distribution models for slack samples, respectively. Thus three HRRP recognition methods based on dual space SVDD are formed. The extensive experiment results for HRRPs of four planes show that the proposed methods have better recognition performance than the recognition method based on single space SVDD.

关键词： High resolution range profile Support vector data description Membership model Cloud model Gaussian mixture model