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Evolution Analysis of Societal Risk Events by Risk Maps 被引量:1
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作者 Nuo Xu Xjjin Tang 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2020年第4期454-467,共14页
Event evolution analysis which provides an effective approach to capture the main context of a story from explosive increased news texts has become the critical basis for many real applications,such as crisis and emer... Event evolution analysis which provides an effective approach to capture the main context of a story from explosive increased news texts has become the critical basis for many real applications,such as crisis and emergency management and decision making.Especially,the development of societal risk events which may cause some possible harm to society or individuals has been heavily concerned by both the government and the public.In order to capture the evolution and trends of societal risk events,this paper presents an improved algorithm based on the method of information maps.It contains an event-level cluster generation algorithm and an evaluation algorithm.The main work includes:1)Word embedding representation is adopted and event-level clusters are chosen as nodes of the events evolution chains which may comprehensively present the underlying structure of events.Meanwhile,clusters that consist of risk-labeled events enable to illustrate how events evolve along the time with transitions of risks.2)One real-world case,the event of"Chinese Red Cross",is studied and a series of experiments are conducted.3)An evaluation algorithm is proposed on the basis of indicators of map construction without massive human-annotated dataset.Our approach for event evolution analysis automatically generates a visual evolution of societal risk events,displaying a clear and structural picture of events development. 展开更多
关键词 Risk maps evolution analysis Baidu hot news search words societal risk events
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Insight into the characteristics of an important evolutionary model bird(Geospiza magnirostris)mitochondrial genome through comparison
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作者 ZHENGGANG XU LIANG WU +4 位作者 JIAHAO CHEN YUNLIN ZHAO CHONGXUAN HAN TIAN HUANG GUIYAN YANG 《BIOCELL》 SCIE 2022年第7期1733-1746,共14页
Darwin’s finches are the most classic case of evolution.Early studies on the evolution of this species were mainly based on morphology.Until now,the mitochondrial genome of Geospiza magnirostris has been sequenced an... Darwin’s finches are the most classic case of evolution.Early studies on the evolution of this species were mainly based on morphology.Until now,the mitochondrial genome of Geospiza magnirostris has been sequenced and the study explored the characteristics of the complete genome of G.magnirostris and verified the evolutionary position of it.The 13 PCGs initiated by ATN codons.The stop codons of three PCGs(ND2,COX3 and ND4)were incomplete,with only T-or TA-replacing complete form TAA or TAG.All the tRNA genes expressed a typical cloverleaf secondary structure,except for tRNA^(Ser1)(AGY),whose dihydrouridine(DHU)arm was lack and instead with a simple loop.In the sequence of the control region of G.magnirostris,we found six simple repeat tandem sequences with a total length of 42 bp.Two characteristic conserved overlapping junction(ATGCTAA)and(CAAGAAAG)were observed as reported for eight selected Passeriformes birds.A special conserved overlapping junction(ATCTTACC)involved in mitochondrial transcription termination was found between tRNA^(Tyr) and COX1 in G.magnirostris’s control region.Four most frequently used amino acids in G.magnirostris’s PCGs were Leu1(CUN),Ile,Thr,Ala.The codon usage of G.magnirostris was relatively average,and there was no particular bias.The ratio Ka/Ks results showed that G.magnirostris receives less natural selection pressure.The phylogenetic relationships and cluster analysis of relative codon usage showed that G.magnirostris and Thraupis episcopus clustered in one branch.The phylogenetic position of G.magnirostris was consistent with the traditional taxonomic of Thraupis.The results supported the conclusion that G.magnirostris belongs to the morphological classification of the family Thraupidae. 展开更多
关键词 Geospiza magnirostris Mitochondrial genome Comparative analysis evolution analysis Phylogenetic relationships
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Genetic Analysis of the Entire Genome of a A/duck/Shanghai/Y20/2006 (H4N6) Avian Influenza Virus
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作者 YANG De-quan GE Fei-fei +4 位作者 LIU Jian JU Hou-bin WANG Jian LIU Pei-hong ZHOU Jin-ping 《Animal Husbandry and Feed Science》 CAS 2013年第2期68-72,共5页
[ Objective] This paper aimed to investigate the origin, characteristics and molecular evolution of duck derived H4N6 subtype avian influ- enza virus (DK/SH/Y20/06) and enrich the epidemiologic data of the waterfowl... [ Objective] This paper aimed to investigate the origin, characteristics and molecular evolution of duck derived H4N6 subtype avian influ- enza virus (DK/SH/Y20/06) and enrich the epidemiologic data of the waterfowl origin AIV. [Method] The entire genome of DK/SH/Y20/06 was amplified and subjected to genome sequencing. The molecular software was used for sequence analysis and phylogenetic tree construction of DK/ SH/Y20/06 with some other reference sequences in GenBank. [Result] The results indicated that the amino acid sequence adjacent to HA cleav- age site was PEKASR ↓ GLF, which was the typical characteristics of the LPAIV. The phylogenetic analysis indicated that the HA gene of the isolate was derived from the Eurasian lineage in the eastern hemisphere. The NA gene was at the same branch with A/rnallard/Yan chen/2005( H4N6), sharing 98.3% sequence identity. The PB2, PB1, NP and PA gene of this isolate had genetically close relationships with H6 subtype AIV which is epidemic in China at present. The M gene fell into the same branch with A/environment/Korea/CSM05/2004( H3N1 ). The NS segment had the highest similarity with A/wild duck/Korea/YS44/2004(H1N2). The eight genes were not at the same branch and shared a low similarity with other H4N6 subtype avian influenza viruses isolated in North America. [Condusion] These data showed that DK/SH/Y20/06(H4N6) was possibly a re- combinant virus derived from H4N6 subtype, H6N2, H6N5, H3N1 and H1 N2 subtype AIV by complex gene recombination in duck. 展开更多
关键词 Duck derived avian influenza virus H4N6 subtype Whole genome sequence Gene tic evolution analysis Gene recombination.
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Evolution of Quaternary Depositional Environments in Lop Nor,Xinjiang:Sedimentary Records from LDK01 Drilling
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作者 Lü Fenglin LIU Chenglin +1 位作者 JIAO Pengcheng ZHAO Yanjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期227-228,共2页
Lop Nur is located in the interior of Asian and the lowest part in the eastern Tarim Basin.It is the final destination of major river systems in Tarim Basin and the accumulation center of salt materials(Xia,1987).As
关键词 grain size analysis evolution of salt lake Lop Nur
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Spectral Synthesis via Mean Field approach to Independent Component Analysis
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作者 Ning Hu Shan-Shan Su Xu Kong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第3期51-62,共12页
We apply a new statistical analysis technique, the Mean Field approach to Independent Component Analysis(MF-ICA) in a Bayseian framework, to galaxy spectral analysis. This algorithm can compress a stellar spectral l... We apply a new statistical analysis technique, the Mean Field approach to Independent Component Analysis(MF-ICA) in a Bayseian framework, to galaxy spectral analysis. This algorithm can compress a stellar spectral library into a few Independent Components(ICs), and the galaxy spectrum can be reconstructed by these ICs. Compared to other algorithms which decompose a galaxy spectrum into a combination of several simple stellar populations, the MF-ICA approach offers a large improvement in efficiency. To check the reliability of this spectral analysis method, three different methods are used:(1) parameter recovery for simulated galaxies,(2) comparison with parameters estimated by other methods, and(3) consistency test of parameters derived with galaxies from the Sloan Digital Sky Survey. We find that our MF-ICA method can not only fit the observed galaxy spectra efficiently, but can also accurately recover the physical parameters of galaxies. We also apply our spectral analysis method to the DEEP2 spectroscopic data, and find it can provide excellent fitting results for low signal-to-noise spectra. 展开更多
关键词 methods: data analysis -- methods: statistical -- galaxies: evolution -- galaxies: fundamentalparameters -- galaxies: stellar content
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Expression and contribution of microphthalmia-associated transcription factor to the melanin deposition in Liancheng white ducks
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作者 XIN Qing-wu MIAO Zhong-wei +6 位作者 LIU Zhao-yuan LI Li ZHANG Lin-li ZHU Zhi-ming ZHANG Zhenghong ZHENG Nen-zhu WANG Zheng-chao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第3期800-809,共10页
The present study investigates the expression of microphthalmia-associated transcription factor(MITF) and its contribution to the melanin deposition in Liancheng white ducks.Nested PCR was used to clone the MITF gene ... The present study investigates the expression of microphthalmia-associated transcription factor(MITF) and its contribution to the melanin deposition in Liancheng white ducks.Nested PCR was used to clone the MITF gene sequence from the skin tissue of female Liancheng white ducks.Ultraviolet spectrophotometry was used to detect the melanin deposition.MITF mRNA expression and melanin deposition in different tissues and organs were detected and their correlation was analyzed.The MITF gene(GenBank number: MG516570) was 1 323 bp in length,contains a complete CDS region(34-1 323 bp) and codes 429 amino acids with 100% homology to the MITF of Anas platyrhynchos and over 95% homology to those of Gallus gallus and Coturnix japonica.Genetic evolution analysis reveals a close relationship of Liancheng white ducks with A.platyrhynchos,and also to lesser extents with Anser cygnoides,silky fowl and G.gallus,as well as Sus scrofa,Ovis aries and other mammals.Real-time quantitative PCR(qPCR) analysis demonstrated that MITF was expressed in skin,gizzard,liver,kidney and muscle,and of these tissues,its expression was the highest in the skin tissue(skin>gizzard>liver>kidney>muscle).Ultraviolet spectrophotometry showed that melanin deposition was positively correlated with the MITF expression level in these five tissues and organs(P<0.05).Together,these results demonstrated a tissue-specific pattern of MITF expression and a positive correlation between MITF expression and melanin deposition,indicating that MITF expression may contribute to the melanin deposition in Liancheng white ducks. 展开更多
关键词 microphthalmia-associated transcription factor genetic evolution analysis melanin deposition Liancheng white ducks
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A novel testability model for health management of heading attitude system 被引量:2
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作者 Liu Guanjun Yang Shuming +1 位作者 Qiu Jing Yang Peng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期201-208,共8页
Prognostics and health management (PHM) is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early... Prognostics and health management (PHM) is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early design stage of system early design stage is deemed as a fundamental way to improve PHM performance, and testability model is the base of testability analysis and design. This paper discusses a hierarchical model-based approach to testability modeling and analysis for heading attitude system health management. Quantified directed graph, of which the nodes represent components and tests and the directed edges represent fault propagation paths, is used to describe fault-test dependency, and quantitative testability information is assigned to nodes and directed edges. The fault dependencies between nodes can be obtained by functional fault analysis methodology that captures the physical architecture and material flows such as energy, heat, data, and so on. By incorporating physics of failure models into component, the dynamic process of a failing or degrading component can be projected onto system behavior, i.e., system symptoms. Then, the analysis of extended failure modes, mechanisms and effects is utilized to construct fault evolution-test dependency. Using this integrated model, the designers and system analysts can assess the test suite's fault detectability, fault isolability and fault predictability. And heading attitude system application results show that the proposed model can support testability analysis and design for PHM very well. 展开更多
关键词 Fault evolution Functional fault analysis Physics of failure model Prognostics and health management Quantified directed graph Testability analysis
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