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A Fusion Based Particle Filter TBD Algorithm for Dim Targets

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Chinese Journal of Electronics 2015年第3期24卷 590-595页

作者： YU Hongbo WANG Guohong cao Qian SUN yun Institute of Information Fusion Naval Aeronautical and Astronautical University Library Naval Aeronautical and Astronautical University

A Fusion based particle filter track-beforedetect algorithm(FPF-TBD) is proposed for dealing with dim targets, in which the importance density function of the Particle filter(PF) is generated by means of a fusion algorithm. In order to construct an accurate approximation to the true proposal distribution, the state at each time scan is predicted according to the Extended Kalman filter algorithm(EKF) and the Unscented Kalman filter(UKF) simultaneously. The information, based on the recursion of the weights, is gathered over multiple scans, and the detection decision is made based on tracking results at the end of the processing chain. By making best use of the recent measurements, this new proposed method can obtain an accurate approximation to the system and as a result, improve the track accuracy and detection performance. Simulation results illustrate the effectiveness of this approach.

关键词： Particle filter Track-before-detect Dim targets Importance density function Fusion algorithm

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： ling-ling Chen Ren-Fei cao Hua Ke Zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization

Adiabatic approximation in PT-symmetric quantum mechanics

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Science China(Physics,Mechanics & Astronomy) 2014年第10期57卷 1835-1839页

作者： GUO ZhiHua cao HuaiXin LU ling College of Mathematics and Information Science Shaanxi Normal University Section of Military Operation Research Xi'an Military Academy

In this paper, we present a quantitative sufficient condition for adiabatic approximation in PT-symmetric quantum mechanics,which yields that a state of the PT-symmetric quantum system at any time will remain approximately in the m-th eigenstate up to a multiplicative phase factor whenever it is initially in the m-th eigenstate of the Hamiltonian. In addition, we estimate the approximation errors by the distance and the fidelity between the exact solution and the adiabatic approximate solution to the time evolution equation, respectively.

关键词： PT-symmetry time evolution equation adiabatic approximation error estimation

Targeting synaptic pathology in Alzheimer’s disease

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Zoological Research 2024年第4期45卷 875-876页

作者： Jing cao yun-Wu Zhang Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by memory and cognitive *** two primary pathological hallmarks of AD include the accumulation ofβ-amyloid(Aβ)plaques and formation of neurofibrillary tangles(NFTs)composed predominantly of hyperphosphorylated tau protein(Zhang et al.,2023).Moreover,synaptic dysfunction is considered another crucial factor in AD pathogenesis and is closely associated with cognitive ***,synaptic damage,loss,and dysfunction manifest earlier than the pathological features of Aβplaques and NFTs(Knopman et al.,2021).Therefore,understanding the mechanisms underlying synaptic dysfunction in AD is vital for providing insights into disease mechanisms and developing novel therapeutic strategies.

关键词： Alzheimer Aβ tau

Inhibition Effect of shRNA on VEGF-C in Breast Cancer Cells

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Chinese Journal of Cancer Research 2009年第3期21卷 202-206页

作者： Xi-ling Gu You-de cao Department of Pathology Chongqing Medical University Chongqing 400016 China

Objective： To investigate the effect of RNA interfering on VEGF-C in MDA-MB-231 cells. Methods： Three small interfering RNAs （siRNAa, siRNAb, siRNAc） were prepared. The most efficient one was screened and short hairpin （shRNA） was designed, the recombinant plasmid pGenesil-1/VEGF-C was constructed, and transfeeted into MDA-MB-231 cells by Lipofectamine TM 2000. RT-PCR, Western-blot an immunohistochemical methods were performed to detect the expression of VEGF-C. Results： RT-PCR results showed that siRNAa, siRNAb, siRNAc could inhibit the growth of MDA-MB-231 cells, among which, siRNAa was the most significant, with an inhibition rate of 72.1%. The recombinant plasmid pGenesil-1/VEGF-C was successfully constructed using shRNA and pGenesil-1. VEGF-C expression was significantly inhibited as determined by RT-PCR, immunocytochemistry staining and Western blot （P〈0.05）. Conclusion： shRNA RNAi technology could silence the expression of VEGF-C in MDA-MB-231 cells, which suggested that the technology may be one of the effective methods for inhibiting lymphangiogenesis in breast cancer.

关键词： siRNA shRNA MDA-MB-231 Cells VEGF-C pGenesil-1

High Pressure Treatment Changes Spoilage Characteristics and Shelf Life of Pacific Oysters(Crassostrea gigas)During Refrigerated Storage

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Journal of Ocean University of China 2017年第2期16卷 351-355页

作者： cao Rong ZHAO ling LIU Qi Department of Food Engineering and Nutrition Yellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071P.R.China

The effects of high pressure(HP) treatment on spoilage characteristic and shelf life extension of Pacific oysters(Crassostrea gigas) during refrigerated storage were *** showed that HP treatment of 275 MPa for 3 min or 300 MPa for 2 min could achieve 100% full release of oyster adductor muscle,pressures higher than 350 MPa caused excessive release as the shells of oysters were broken,thus use of higher pressures should be cautious in oyster processing industry because of its adverse impact on the appearance of *** treatment(300 MPa,2 min) was proper for the shucking of Pacific oyster(Crassostrea gigas) in *** treatment caused no organoleptic ***,HP treatment resulted in obvious differences in biochemical spoilage indicators(p H,TVB-N and TBARS) changes and volatile compounds profile determined by electronic nose during *** treatment(300 MPa,2 min) also led to a reduction of aerobic bacterial count(APC) by 1.27 log ***,the APC values of oysters treated by HP were always lower than those of the control samples during *** on the organoleptic,biochemical and microbiological indicators,shelf life of 6-8 d for control and 12 d for HP-treated oysters could be *** treatment showed great potential in oyster processing and preservation.

关键词： high pressure processing oyster spoilage E-nose shelf life

A clinical study to determine the threshold of bronchodilator response for diagnosing asthma in Chinese children

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World Journal of Pediatrics 2019年第6期15卷 559-564页

作者： Xiao-Hui Kang Wan Wang ling cao Children's Hospital Affiliated to the Capital Institute of Pediatrics No.2 Ya bao RoadChaoyang DistrictBeijingChina Shanxi Provincial Children's Hospital TaiyuanChina

Background There is few objective,clinically feasible and inexpensive test for diagnosing childhood *** want to find an ideal way to solve *** The control group was 301 non-asthmatic children,and the asthma group was 286 asthmatic *** asthmatic children were divided into three groups according to the severity of their ***-and post-bronchodilator spirometer tests were performed,and the main spirometer parameters were *** bronchodilator response(BDR)[BDR is used to determine the reversibility of airway obstruction by measuring the changes of forced expiratory volume in the first second(FEV1)before and after inhalation of bronchodilators]was then determined,and the optimal threshold of BDR for diagnosing childhood asthma was *** 301 non-asthmatic children and 286 asthmatic children participated in the study,the demographics were *** 1 for pre-bronchodilator of asthmatic children was significantly lower than that of non-asthmatic children(P≤0.01).BDR of non-asthmatic children was 3.30±3.85%.BDR of asthmatic children was 9.45±9.15%.There was no significant difference in BDR for patients with different severities of asthma within the *** had no statistical correlation with gender,age,height,weight in neither non-asthmatic children nor asthmatic *** the receiver-operating characteristic curve,a BDR threshold of≥7.5%offered an optimal balance in asthma diagnosis with a sensitivity rate of 50.7%and specificity rate of 87.7%.Meanwhile,with a BDR threshold of≥12%,the sensitivity rate was 28.7%and the specificity rate was 96.3%.Conclusion A BDR threshold of≥7.5%has more value in childhood asthma diagnosis as compared to≥12%.

关键词： Asthma diagnosis Bronchodilator response Threshold

A Novel CCA-NMF Whitening Method for Practical Machine Learning Based Underwater Direction of Arrival Estimation

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Journal of Beijing Institute of Technology 2024年第2期33卷 163-174页

作者： yun Wu Xinting Li Zhimin cao School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China

Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical *** to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based DOA estimation methods trained on simulated Gaussian noised array data cannot be directly applied to actual underwater DOA estimation *** order to deal with this problem,environmental data with no target echoes can be employed to analyze the non-Gaussian ***,the obtained information about non-Gaussian components can be used to whiten the array *** on these considerations,a novel practical sonar array whitening method was ***,based on a weak assumption that the non-Gaussian components in adjacent patches with and without target echoes are almost the same,canonical cor-relation analysis(CCA)and non-negative matrix factorization(NMF)techniques are employed for whitening the array *** the whitened array data,machine learning based DOA estimation models trained on simulated Gaussian noised datasets can be used to perform underwater DOA estimation *** results illustrated that,using actual underwater datasets for testing with known machine learning based DOA estimation models,accurate and robust DOA estimation performance can be achieved by using the proposed whitening method in different underwater con-ditions.

关键词： direction of arrival(DOA) sonar array data underwater disturbance machine learn-ing canonical correlation analysis(CCA) non-negative matrix factorization(NMF)

Effective DOA Estimation Under Low Signal-to-Noise Ratio Based on Multi-Source Information Meta Fusion

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Journal of Beijing Institute of Technology 2021年第4期30卷 377-396页

作者： yun Wu Xiukun Li Zhimin cao Acoustic Science and Technology Laboratory and the College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechniqueHarbin 150001China School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318HeilongjiangChina

Efficiently performing high-resolution direction of arrival(DOA)estimation under low signal-to-noise ratio(SNR)conditions has always been a challenge task in the ***-ously,in order to address this problem,the key is how to mine or reveal as much DOA related in-formation as possible from the degraded array ***,it is certain that there is no per-fect solution for low SNR DOA estimation designed in the way of ***,this paper proposes to explore in depth the complementary DOA related information that exists in spa-tial spectrums acquired by different basic DOA ***,these basic spatial spec-trums are employed as the input of multi-source information fusion *** the multi-source in-formation fusion model is composed of three heterogeneous meta learning machines,namely neural networks(NN),support vector machine(SVM),and random forests(RF).The final meta-spec-trum can be obtained by performing a final decision-making *** results illus-trate that the proposed information fusion based DOA estimation method can really make full use of the complementary information in the spatial spectrums obtained by different basic DOA *** under low SNR conditions,promising DOA estimation performance can be achieved.

关键词： direction of arrival(DOA) signal-to-noise ratio(SNR) information fusion meta-learn-ing spatial spectrum