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血清Th1/Th2趋化因子CXCL10、CCL22水平与溃疡性结肠炎患者疾病活动度的关系
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作者 周艳阳 陈立平 +1 位作者 郭海霞 李阳 《海南医学》 CAS 2024年第4期527-531,共5页
目的探讨溃疡性结肠炎(UC)患者血清1型辅助性T细胞(Th1)/2型辅助性T细胞(Th2)趋化因子配体10(CXCL10)、CC类趋化因子22(CCL22)表达水平及其与疾病活动度的关系。方法选择2019年1月至2022年6月河南中医药大学第一附属医院收治的157例UC... 目的探讨溃疡性结肠炎(UC)患者血清1型辅助性T细胞(Th1)/2型辅助性T细胞(Th2)趋化因子配体10(CXCL10)、CC类趋化因子22(CCL22)表达水平及其与疾病活动度的关系。方法选择2019年1月至2022年6月河南中医药大学第一附属医院收治的157例UC患者作为UC组,43例同期健康体检者作为对照组。采用UC内镜下严重程度指数(UCEIS)评分评估UC疾病的活动度,采用改良梅奥(Mayo)评分评估UC病情程度。UC组患者根据疾病活动度分为缓解组90例和活动组67例。比较三组受检者的血清CXCL10、CCL22、红细胞沉降率(ESR)、血清C反应蛋白(CRP)、中性粒细胞计数和白蛋白(Alb)。采用Pearson相关性分析法分析上述各项指标与改良Mayo评分、UCEIS评分的相关性,采用受试者工作特征曲线(ROC)分析血清CXCL10、CCL22对UC疾病活动度的预测价值。结果活动组患者的血清CXCL10、CCL22、ESR、CRP、中性粒细胞计数分别为(64.06±11.57)ng/mL、(189.15±36.11)ng/mL、(10.95±1.42)mm/h、(15.74±2.56)mg/L、(9.71±0.93)×10^(9)/L,明显高于缓解组的(49.05±11.75)ng/mL、(149.27±27.17)ng/mL、(7.61±0.89)mm/h、(11.53±1.45)mg/L、(5.67±0.82)×10^(9)/L,缓解组的上述各项指标明显高于对照组的(21.21±6.21)ng/mL、(138.22±23.72)ng/mL、(4.98±0.65)mm/h、(7.76±1.48)mg/L、(3.81±0.75)×10^(9)/L,但活动组患者的Alb为(7.21±1.42)g/L,明显低于缓解组的(9.39±1.38)g/L和对照组的(13.26±2.43)g/L,且缓解组明显低于对照组,差异均有统计学意义(P<0.05);活动组患者的改良Mayo评分、UCEIS评分分别为(7.06±0.88)分、(4.39±0.47)分,明显高于缓解组的(3.58±0.72)分、(2.17±0.36)分,差异均有统计学意义(P<0.05);经Pearson相关性分析结果显示,UC患者CXCL10、CCL22、ESR、CRP、中性粒细胞计数与改良Mayo评分、UCEIS评分均呈正相关(P<0.05),Alb与改良Mayo评分、UCEIS评分均呈负相关(P<0.05);经ROC分析结果显示,血清CXCL10、CCL22及两者联合检测预测UC疾病活动度的曲线下面积(AUC)分别为0.813、0.810和0.888,联合预测较单一指标预测的准确度更高。结论UC患者血清CXCL10、CCL22水平升高程度与疾病活动度情况具有密切的关系,两者联合检测对UC患者疾病活动度情况具有较高的预测价值。 展开更多
关键词 溃疡性结肠炎 TH1/TH2 趋化因子配体10 cc类趋化因子22 疾病活动度 相关性
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Correlation Study on Grain Size Characteristics and Geotechnical Properties of Surface Sediments in Qingdao Offshore Area
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作者 LI Anlong WANG Panpan +5 位作者 GUO Xijun JI Xiangkun SHEN Kunming LIN Lin YAN Zhichao YUAN Lin 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期721-730,共10页
The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study del... The comprehension of sediment grain size parameters and the corresponding sedimentary environment holds paramount importance in elucidating the engineering geological attributes of the subaqueous seabed.This study delineated the sedimentary environment zoning in the northern sea area of Qingdao through cluster analysis of grain size parameters derived from 123 surface sediment samples.The study analyzed the correlation between sediment geotechnical indices and grain size parameters across diverse sedimentary environments.A correlation equation was established for samples exhibiting a strong correlation.The study found four distinct sedimentary environments in the study area:coastal,transitional,shallow sea,and residual.Within the same sedimentary environment,the average grain size and sorting coefficient exhibit significant correlations with geotechnical indices such as water content,density,shear strength,plastic limit,liquid limit,and plastic index.However,notable disparities in the correlation between grain size parameters and geotechnical indices emerge across different sedimentary environments. 展开更多
关键词 grain size parameters cluster analysis sedimentary environment correlationS geotechnical indexes
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Study on growing correlation length prior to the earthquakes occurred in Gansu Province and its nearby area 被引量:3
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作者 RONG Dai-lu(荣代潞) +3 位作者 LI Ya-rong(李亚荣) LIU Xu-zhou(刘旭宙) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第5期564-570,共8页
The growing correlation length prior to the moderate-great earthquakes occurred in Gansu Province and its nearby area since 1986 has been studied using the method of single-link cluster analysis (SLC). According to di... The growing correlation length prior to the moderate-great earthquakes occurred in Gansu Province and its nearby area since 1986 has been studied using the method of single-link cluster analysis (SLC). According to different conditions in the source area, the circular spatial window centered in the epicenter and the parallelgrammic spatial window along the fault belt have been selected. The results show that the phenomena of growing correlation length have been observed before the earthquakes studied in the paper. 展开更多
关键词 moderate-great earthquake correlation length single-link cluster analysis GANSU
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Spatial correlation-based characterization of acoustic emission signal-cloud in a granite sample by a cube clustering approach 被引量:6
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作者 Dongjie Xue Zepeng Zhang +4 位作者 Cheng Chen Jie Zhou Lan Lu Xiaotong Sun Yintong Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第4期535-551,共17页
To extract more in-depth information of acoustic emission(AE)signal-cloud in rock failure under triaxial compression,the spatial correlation of scattering AE events in a granite sample is effectively described by the ... To extract more in-depth information of acoustic emission(AE)signal-cloud in rock failure under triaxial compression,the spatial correlation of scattering AE events in a granite sample is effectively described by the cube-cluster model.First,the complete connection of the fracture network is regarded as a critical state.Then,according to the Hoshen-Kopelman(HK)algorithm,the real-time estimation of fracture con-nection is effectively made and a dichotomy between cube size and pore fraction is suggested to solve such a challenge of the one-to-one match between complete connection and cluster size.After,the 3D cube clusters are decomposed into orthogonal layer clusters,which are then transformed into the ellip-soid models.Correspondingly,the anisotropy evolution of fracture network could be visualized by three orthogonal ellipsoids and quantitatively described by aspect ratio.Besides,the other three quantities of centroid axis length,porosity,and fracture angle are analyzed to evaluate the evolution of cube cluster.The result shows the sample dilatancy is strongly correlated to four quantities of aspect ratio,centroid axis length,and porosity as well as fracture angle.Besides,the cube cluster model shows a potential pos-sibility to predict the evolution of fracture angle.So,the cube cluster model provides an in-depth view of spatial correlation to describe the AE signal-cloud. 展开更多
关键词 Acoustic emission Triaxial compression Fracture connection Spatial correlation Cube cluster model DILATANCY
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Correlation and Path Coefficient and Chi-square Distance Cluster Analysis for Several Characteristics in Tobacco Germplasm Resource 被引量:1
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作者 LI Wenping ZHU Lieshu +3 位作者 ZHAO Songyi LIANG Qizheng WANG Yuchao TAN Xi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第1期10-15,共6页
Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the ... Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related. 展开更多
关键词 flue-cured tobacco correlation analysis path coefficient analysis cluster analysis
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Study on Evaluation of the Rainstorm Disaster in Fujian Province Based on Spectral Clustering Model with Grey Correlation Analysis 被引量:3
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作者 YE Xiao-ling YAO Zhen-zhen 《Meteorological and Environmental Research》 2012年第6期45-49,共5页
[ Objective] The research aimed to study assessment index system of the rainstorm disaster in Fujian Province based on spectral cluste- ring model with grey correlation analysis. [Method] According to meteorological d... [ Objective] The research aimed to study assessment index system of the rainstorm disaster in Fujian Province based on spectral cluste- ring model with grey correlation analysis. [Method] According to meteorological disaster yearbook in Fujian Province, by comprehensively consider- ing disaster-inducing factor, disaster-inducing environment, disaster-sustaining body and regional disaster-prevention level, evaluation index system of the regional rainstorm disaster in Fujian was established. By spectral clustering model based on grey correlation analysis, dsk zoning of the rain- storm disaster was conducted in each area of Fujian. Finally, effect and application of the clustering model were analyzed by case research. [ Re- sult] In order to dig immanent connection among regional characteristics and improve disaster-preventing linkage performance of the evaluation unit, a spectral clustering model based on grey correlation analysis was used to conduct risk zoning of the rainstorm disaster in Fujian Province. Moreo- ver, combined weight was introduced to judge each evaluation index, so as to adjust clustering model. By case study, rainstorm disaster levels in 67 counties were obtained. Internal characteristics of each type were analyzed, and main correlation factors of each type were extracted. It was compared with statistical result of the rainstorm disaster, verifying validity and feasibility of the model. [ Conclusion] The method was feasible, and its evaluated result had better differentiation and decision accuracv. 展开更多
关键词 Fujian Province Grey correlation Spectral clustering Rainstorm disaster EVALUATION China
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SPATIAL CORRELATION DESCRIPTION OF DEFORMATION OBJECT BASED ON FUZZY CLUSTERING AND GEOLOGICAL ANALYSIS
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作者 YIN HuiYIN Hui,Associate Professor,School of Geo_science and Surveying Engineering,WTUSM,129 Luoyu Road,Wuhan 430079,China 《Geo-Spatial Information Science》 2000年第3期69-72,共4页
The methods of deformation analysis and modeling at single point are realized easily now,but available approaches do not make full use of the information from monitoring points and can not reveal integrated deformatio... The methods of deformation analysis and modeling at single point are realized easily now,but available approaches do not make full use of the information from monitoring points and can not reveal integrated deformation regularity of a deformable body.This paper presents a fuzzy clusetering method to analyze the correlative relations of multiple points in space,and then the spatial model for a practical dangerous rockmass in the area of Three Gorges,Yangtze River is established,in which the correlation of six points in space is analyzed by geological investigation and fuzzy set theory. 展开更多
关键词 fuzzy clustering GEOLOGICAL investigation correlation DESCRIPTION DEFORMATION OBJECT
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Particle Swarm Optimized Optimal Threshold Value Selection for Clustering based on Correlation Fractal Dimension
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作者 Anuradha Yarlagadda J. V. R. Murthy M. H. M. Krishna Prasad 《Applied Mathematics》 2014年第10期1615-1622,共8页
The work on the paper is focused on the use of Fractal Dimension in clustering for evolving data streams. Recently Anuradha et al. proposed a new approach based on Relative Change in Fractal Dimension (RCFD) and dampe... The work on the paper is focused on the use of Fractal Dimension in clustering for evolving data streams. Recently Anuradha et al. proposed a new approach based on Relative Change in Fractal Dimension (RCFD) and damped window model for clustering evolving data streams. Through observations on the aforementioned referred paper, this paper reveals that the formation of quality cluster is heavily predominant on the suitable selection of threshold value. In the above-mentionedpaper Anuradha et al. have used a heuristic approach for fixing the threshold value. Although the outcome of the approach is acceptable, however, the approach is purely based on random selection and has no basis to claim the acceptability in general. In this paper a novel method is proposed to optimally compute threshold value using a population based randomized approach known as particle swarm optimization (PSO). Simulations are done on two huge data sets KDD Cup 1999 data set and the Forest Covertype data set and the results of the cluster quality are compared with the fixed approach. The comparison reveals that the chosen value of threshold by Anuradha et al., is robust and can be used with confidence. 展开更多
关键词 correlation FRACTAL DIMENSION FRACTAL DIMENSION clustering Particle SWARM Optimization Data STREAM clustering
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大规模海上CCS/CCUS 集群项目研究与思考 被引量:2
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作者 于航 刘强 +4 位作者 李彦尊 李林涛 孙丽丽 何庆阳 鲁建荣 《石油科技论坛》 2023年第2期90-95,共6页
全球碳捕集、利用与封存(CCS/CCUS)产业仍处于商业化早期阶段,近年不断加快该领域的投资布局,趋向规模化集群化发展。推动CCS/CCUS集群全产业链示范项目,开展技术、商业、政策可行性研究和评估,对我国推进规模化技术研发、示范和产业化... 全球碳捕集、利用与封存(CCS/CCUS)产业仍处于商业化早期阶段,近年不断加快该领域的投资布局,趋向规模化集群化发展。推动CCS/CCUS集群全产业链示范项目,开展技术、商业、政策可行性研究和评估,对我国推进规模化技术研发、示范和产业化应用,顺利实现碳达峰碳中和目标具有重要意义。与“一对一”的简单模式相比,CCS/CCUS集群项目要面对更加复杂的碳排放源,需要规模更大、可靠性更高的封存场地,这给捕集净化处理及选区评价带来了极大挑战。海上项目受限于空间小、投资高、后期维护困难等因素,CO_(2)输送、封存及监测环节的技术和方案与陆上存在较大不同。现阶段我国CCS/CCUS集群项目发展面临着技术、成本、政策、法规、商业模式等诸多挑战。探讨了我国大规模海上CCS/CCUS集群项目推动过程中的关键问题,指出了碳排放源的复杂性使捕集环节难度增加,满足规模化封存需要的场址选择是关键,全产业链技术方案的可靠性和经济性是保障,推动价值链的实现是项目实施的原动力。 展开更多
关键词 碳捕集、利用与封存(ccS/ccUS) 集群项目 规模化 海上ccS/ccUS 全产业链
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The Use of Fuzzy Clustering and Correlation to Implement an Heart Disease Diagnosing System in FPGA
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作者 Evaldo Renó Faria Cintra Tales Cleber Pimenta Robson Luiz Moreno 《Journal of Software Engineering and Applications》 2011年第8期491-496,共6页
In this paper we present a signal processing method capable of detecting cardiopathies in electrocardiograms that was implemented in FPGA. The adopted procedure is based on fuzzy clustering to reduce the amount of dat... In this paper we present a signal processing method capable of detecting cardiopathies in electrocardiograms that was implemented in FPGA. The adopted procedure is based on fuzzy clustering to reduce the amount of data sampling, and a comparison with samples from a previously established database. By using the correlation method on the samples, it is possible to establish an initial indication of a cardiopathy. The reduced number of samples of the clustering process turns the processing simpler and allows its hardware implementation. According to the tests conducted, the method achieves 91% correct diagnoses. 展开更多
关键词 CARDIOPATHY HEART correlation FUZZY clustering ELECTROCARDIOGRAM
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血清CCL11在阿尔茨海默病患者诊断及治疗中的作用研究
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作者 曾令勇 黄其志 +3 位作者 黎荣 甘受益 虞冬辉 钱冉 《中国现代药物应用》 2023年第6期88-91,共4页
目的分析血清CC修饰趋化因子11(CCL11)在阿尔茨海默病(AD)患者诊断及治疗中的作用。方法选择60例AD患者作为AD组,另选择67例轻度认知障碍患者作为轻度认知障碍组,100例健康受试者作为对照组。对照组采用安慰剂(维生素E)治疗,AD组及轻度... 目的分析血清CC修饰趋化因子11(CCL11)在阿尔茨海默病(AD)患者诊断及治疗中的作用。方法选择60例AD患者作为AD组,另选择67例轻度认知障碍患者作为轻度认知障碍组,100例健康受试者作为对照组。对照组采用安慰剂(维生素E)治疗,AD组及轻度认知障碍组患者均采用多奈哌齐治疗。比较三组治疗前后血清CCL11水平、不同程度AD患者血清CCL11水平,分析AD患者病情严重程度与血清CCL11水平的相关性。结果治疗前1 d及治疗后1 d,对照组血清CCL11分别为(16.29±3.04)、(16.74±3.19)pg/ml,轻度认知障碍组分别为(40.49±6.29)、(17.58±3.47)pg/ml,AD组分别为(71.54±19.74)、(32.87±4.57)pg/ml。治疗前1 d及治疗后1 d,AD组患者血清CCL11水平均高于轻度认知障碍组、对照组,差异均有统计学意义(P<0.05)。治疗前1 d,轻度认知障碍组患者的血清CCL11水平高于对照组,差异具有统计学意义(P<0.05)。治疗后1 d,AD组和轻度认知障碍组患者的血清CCL11水平均低于本组治疗前1 d,差异具有统计学意义(P<0.05)。治疗后1 d,轻度认知障碍组与对照组血清CCL11水平比较差异无统计学意义(P>0.05)。治疗前1 d及治疗后1 d,轻度AD患者血清CCL11分别为(63.67±3.06)、(30.62±4.16)pg/ml,中度AD患者分别为(72.87±5.29)、(32.98±4.19)pg/ml,重度AD患者分别为(96.71±7.06)、(40.64±8.15)pg/ml。治疗前1 d,重度AD患者血清CCL11水平均高于中度、轻度AD患者,中度AD患者血清CCL11水平高于轻度AD患者,差异有统计学意义(P<0.05)。治疗后1 d,重度、中度、轻度AD患者的血清CCL11水平均低于治疗前1 d,重度AD患者血清CCL11水平高于中度、轻度AD患者,差异有统计学意义(P<0.05);中度与轻度AD患者血清CCL11水平比较,差异无统计学意义(P>0.05)。AD患者的病情严重程度与血清CCL11水平呈正相关(r=0.236,P=0.007<0.05)。结论血清CCL11水平可反应AD病情严重程度,并且可成为诊断AD的血清因子。 展开更多
关键词 血清cc修饰趋化因子11 阿尔茨海默病 诊断 治疗 相关性
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Clustering Countries on COVID-19 Data among Different Waves Using K-Means Clustering
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作者 Muhtasim   Md. Abdul Masud 《Journal of Computer and Communications》 2023年第7期1-14,共14页
The COVID-19 pandemic has caused an unprecedented spike in confirmed cases in 230 countries globally. In this work, a set of data from the COVID-19 coronavirus outbreak has been subjected to two well-known unsupervise... The COVID-19 pandemic has caused an unprecedented spike in confirmed cases in 230 countries globally. In this work, a set of data from the COVID-19 coronavirus outbreak has been subjected to two well-known unsupervised learning techniques: K-means clustering and correlation. The COVID-19 virus has infected several nations, and K-means automatically looks for undiscovered clusters of those infections. To examine the spread of COVID-19 before a vaccine becomes widely available, this work has used unsupervised approaches to identify the crucial county-level confirmed cases, death cases, recover cases, total_cases_per_million, and total_deaths_per_million aspects of county-level variables. We combined countries into significant clusters using this feature subspace to assist more in-depth disease analysis efforts. As a result, we used a clustering technique to examine various trends in COVID-19 incidence and mortality across nations. This technique took the key components of a trajectory and incorporates them into a K-means clustering process. We separated the trend lines into measures that characterize various features of a trend. The measurements were first reduced in dimension, then clustered using a K-means algorithm. This method was used to individually calculate the incidence and death rates and then compare them. 展开更多
关键词 COVID-19 Epidemic K-Means clustering correlationS Infection Control SARS-CoV-2 Time Series
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Correlation Analysis of Turbidity and Total Phosphorus in Water Quality Monitoring Data
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作者 Wenwu Tan Jianjun Zhang +7 位作者 Xing Liu Jiang Wu Yifu Sheng Ke Xiao Li Wang Haijun Lin Guang Sun Peng Guo 《Journal on Big Data》 2023年第1期85-97,共13页
At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the p... At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the prediction of total phosphorus in water quality has good research significance.This paper selects the total phosphorus and turbidity data for analysis by crawling the data of the water quality monitoring platform.By constructing the attribute object mapping relationship,the correlation between the two indicators was analyzed and used to predict the future data.Firstly,the monthly mean and daily mean concentrations of total phosphorus and turbidity outliers were calculated after cleaning,and the correlation between them was analyzed.Secondly,the correlation coefficients of different times and frequencies were used to predict the values for the next five days,and the data trend was predicted by python visualization.Finally,the real value was compared with the predicted value data,and the results showed that the correlation between total phosphorus and turbidity was useful in predicting the water quality. 展开更多
关键词 correlation analysis CLUSTER water quality predict water quality monitoring data
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一种CCA-层次聚类的基因聚类算法
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作者 林倩闽 《哈尔滨理工大学学报》 CAS 北大核心 2023年第5期85-90,共6页
针对基因芯片技术带来的海量基因表达数据,为了充分挖掘其蕴含的生物信息和潜在的生物机制,提出一种基于CCA-层次聚类的基因聚类算法(CCA-Hc)。该算法在层次聚类的基础上引入典型相关分析,优化相似性矩阵计算方法。首先,利用典型相关分... 针对基因芯片技术带来的海量基因表达数据,为了充分挖掘其蕴含的生物信息和潜在的生物机制,提出一种基于CCA-层次聚类的基因聚类算法(CCA-Hc)。该算法在层次聚类的基础上引入典型相关分析,优化相似性矩阵计算方法。首先,利用典型相关分析方法结合基因的多个特征信息进行基因相关性度量,得到基因相似性矩阵。然后将该相似性矩阵作为层次聚类的邻近矩阵进行凝聚层次聚类。在Oryza sativa L.(水稻)的基因表达数据集上进行CCA-Hc聚类效果测试实验,结果表明,与采用欧式距离的传统层次聚类算法(EUC-Hc)相比,CCA-Hc的内部稳定性指标和生物功能性指标均优于EUC-Hc,具有更佳的鲁棒性和聚类准确性,更有利于去发现基因间的共表达关系。 展开更多
关键词 基因表达数据 聚类算法 典型相关分析 层次聚类
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COPD患者痰液CCR6、CD83、Th1、Th2表达及临床意义
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作者 张洋 《淮海医药》 CAS 2023年第5期454-458,462,共6页
目的:探究CC趋化因子受体6(CCR6)、CD83及辅助性T细胞(Th)1、Th2相关细胞因子在慢性阻塞性肺疾病(COPD)患者痰液中的表达及临床意义。方法:选取2020年8月—2022年11月某院接受治疗的265例COPD患者,根据疾病严重程度将135例急性发作期COP... 目的:探究CC趋化因子受体6(CCR6)、CD83及辅助性T细胞(Th)1、Th2相关细胞因子在慢性阻塞性肺疾病(COPD)患者痰液中的表达及临床意义。方法:选取2020年8月—2022年11月某院接受治疗的265例COPD患者,根据疾病严重程度将135例急性发作期COPD患者纳入AECOPD组,130例稳定期COPD患者纳入COPD稳定期组,选取同期该院健康体检者100例作为正常对照组。采用流式细胞术和酶联免疫吸附试验(ELISA)法检测各组痰液样本中CD83、CCR6及Th1[干扰素-γ(IFN-γ)、肿瘤坏死因子-α(TNF-α)]、Th2[白细胞介素(IL)-4、IL-6]相关细胞因子表达水平,并分析COPD稳定期组上述因子表达水平与慢性阻塞性肺疾病全球倡议(GOLD)肺功能分级、COPD评估测试(CAT)评分及改良版英国医学研究委员会呼吸问卷(mMRC)分级的关系。结果:AECOPD组患者痰液中CD83/CCR6比值(0.73±0.40)低于COPD稳定期组(1.40±0.53)和正常对照组(2.85±1.86),而IFN-γ[(43.45±14.80)pg/mL]、TNF-α[(59.55±21.48)pg/mL]、IL-4[(16.30±4.62)pg/mL]、IL-6[(38.97±13.41)pg/mL]水平高于COPD稳定期组[(32.53±8.45)pg/mL]、(30.27±13.18)pg/mL、(10.32±4.54)pg/mL、(19.64±7.16)pg/mL]和正常对照组[(25.22±6.31)pg/mL、(20.42±7.61)pg/mL、(5.38±1.14)pg/mL、(8.40±2.27)pg/mL]差异均有统计学意义(P<0.05)。随着稳定期COPD患者GOLD肺功能分级和CAT评分增加,痰液中CD83/CCR6比值逐渐降低,而IFN-γ、TNF-α、IL-4、IL-6水平逐渐升高,差异均有统计学意义(P<0.05)。mMRC分级≥2级组患者痰液中CD83/CCR6比值(1.11±0.34)低于mMRC分级<2级组(1.53±0.55),IFN-γ[(37.04±9.55)pg/mL]、TNF-α[(36.85±12.10)pg/mL]、IL-4[(12.33±4.65)pg/mL]、IL-6[(21.57±7.80)pg/mL]水平高于mMRC分级<2级组[(30.66±7.21)pg/mL、(27.55±12.70)pg/mL、(9.49±4.25)pg/mL、(18.84±6.76)pg/mL],差异有统计学意义(P<0.05)。结论:COPD患者痰CD83/CCR6比值降低,Th1和Th2相关细胞因子水平升高,且与COPD患者肺功能状态、CAT评分及mMRC分级有关,可作为临床评估COPD患者病情程度的参考指标。 展开更多
关键词 肺疾病 慢性阻塞性 cc趋化因子受体6 CD83 辅助性T细胞
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基于相关性的大型救援装备模块划分方法
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作者 赵京 张晓丹 +1 位作者 张自强 苗磊 《北京工业大学学报》 CAS CSCD 北大核心 2024年第3期271-281,共11页
为了解决大型救援装备在灾时转运投用效率低的问题,提出了一种基于相关性的大型救援装备模块划分方法。首先建立了零部件相关性评价数学模型,对救援装备零部件之间的相关性进行评价,得到综合相关性矩阵;然后针对救援装备改进了一种层次... 为了解决大型救援装备在灾时转运投用效率低的问题,提出了一种基于相关性的大型救援装备模块划分方法。首先建立了零部件相关性评价数学模型,对救援装备零部件之间的相关性进行评价,得到综合相关性矩阵;然后针对救援装备改进了一种层次聚类算法,基于综合相关性矩阵对零部件进行聚类,得到层次聚类结构;最后建立了救援装备模块划分方案多目标优化模型,基于遗传算法对其中各步骤进行适应性改造,从而求得救援装备的最优模块划分方案。该方法解决了现有方法在救援装备上无法应用的若干问题,其有效性在YS220液压挖掘机上得到应用验证。 展开更多
关键词 模块化 救援装备 相关性 聚类 挖掘机 多目标优化
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欧洲温室型黄瓜种质资源主要农艺性状遗传多样性分析
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作者 曹守军 姚建刚 +7 位作者 张丽莉 王虹云 张瑞清 张安平 范燕山 韩丽 李涛 张英勇 《中国瓜菜》 CAS 北大核心 2024年第4期56-62,共7页
为了研究欧洲温室型黄瓜农艺性状遗传多样性、亲缘关系,明确种质资源的特征特性,为欧洲温室型黄瓜新品种选育提供参考,对搜集并纯化的41份欧洲温室型黄瓜自交系进行了第一雌花节位、叶长、叶宽等18个农艺性状鉴定,并进行遗传多样性、相... 为了研究欧洲温室型黄瓜农艺性状遗传多样性、亲缘关系,明确种质资源的特征特性,为欧洲温室型黄瓜新品种选育提供参考,对搜集并纯化的41份欧洲温室型黄瓜自交系进行了第一雌花节位、叶长、叶宽等18个农艺性状鉴定,并进行遗传多样性、相关性和聚类分析。18个农艺性状间变异系数在13.36%~76.48%之间,变异系数最大的性状为第一雌花节位,达到76.48%;变异系数最小的性状为植株生长势,为13.36%、平均变异系数为27.78%。单瓜质量和单株产量均与第一雌花节位呈显著正相关;果皮颜色与果皮硬度呈显著正相关,与心腔比呈极显著负相关。在遗传相似系数(GS)为1.86时,分为三大类,第一类含有23份黄瓜种质资源,占供试材料的56%;第二类含有4份黄瓜种质资源;第三类含有14份黄瓜种质资源。41份欧洲温室型黄瓜材料遗传差异较大,有丰富的遗传多样性,具有较大的育种目标选择潜力,为欧洲温室型黄瓜新品种选育提供了优良资源。 展开更多
关键词 黄瓜 欧洲温室型 多样性分析 相关性分析 聚类分析
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秋子梨果实矿质元素含量差异分析
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作者 刘春光 齐丹 +7 位作者 任爱华 杨悦 胡颖慧 刘畅 董航 汤佳翰 顾广军 曹玉芬 《中国果树》 2024年第4期45-54,共10页
以黑龙江省36份秋子梨果实为试材,采用ICP-MS法对果皮和果肉中12种矿质元素含量进行测定并比较分析。结果表明:秋子梨果实中各矿质元素的平均含量依次为K>P>Ca>Mg>Na>Al>Fe>Zn>Cu>Cr>Pb>Cd,不同种质... 以黑龙江省36份秋子梨果实为试材,采用ICP-MS法对果皮和果肉中12种矿质元素含量进行测定并比较分析。结果表明:秋子梨果实中各矿质元素的平均含量依次为K>P>Ca>Mg>Na>Al>Fe>Zn>Cu>Cr>Pb>Cd,不同种质中果皮和果肉各元素的含量差异明显,野生资源的果实矿质元素含量高于选育品种、农家品种和优良品系。相关性分析结果表明,果皮和果肉中的P、K、Fe、Cu和Zn这5种元素之间存在极显著正相关。聚类分析结果表明,根据果皮或果肉的矿质元素含量,36份秋子梨种质可分为2个略有不同的类别。主成分分析表明,S23、S20、S16和S10是果实矿质元素总含量较高的品种,可优先作为功能性品种选育种质材料,为秋子梨果实矿质元素的遗传改良提供更为深入和有价值的依据。 展开更多
关键词 秋子梨 矿质元素 相关性分析 主成分分析 聚类分析
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基于主成分和聚类分析的50份冬小麦材料主要农艺性状评价
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作者 郑彩霞 孙小东 +3 位作者 杨振常 李榕鑫 闫文君 张宗迪 《甘肃农业大学学报》 CAS CSCD 北大核心 2024年第1期102-112,共11页
【目的】了解冬小麦农艺性状间的关系,探究冬小麦农艺性状对产量的影响,从而筛选高产冬小麦品系。【方法】本研究以50份冬小麦品种(系)为研究对象,对其15个农艺性状进行了遗传变异分析、相关分析、主成分分析和聚类分析。【结果】遗传... 【目的】了解冬小麦农艺性状间的关系,探究冬小麦农艺性状对产量的影响,从而筛选高产冬小麦品系。【方法】本研究以50份冬小麦品种(系)为研究对象,对其15个农艺性状进行了遗传变异分析、相关分析、主成分分析和聚类分析。【结果】遗传变异分析表明,供试材料农艺性状存在差异,除生育期变异系数为0.71%外,其他农艺性状变异系数较大,为7.46%~51.68%。产量与穗粒质量(0.935**)、千粒质量(0.740**)、穗粒数(0.616**)呈极显著正相关,与小穗数(0.289*)呈显著正相关,与其他农艺性状相关性不显著。主成分分析结果表明,小穗数、穗粒数、小穗粒数、穗粒质量、千粒质量对冬小麦产量提高有较大的正向作用,株高、不育小穗数对冬小麦产量提高有负作用,有27份参试材料基于15个农艺性状综合表现好。聚类分析结果表明,50份冬小麦供试材料划分为多粒高产型、多粒中产型、少粒低产型3大类群,各类群特征表现明显。【结论】50份冬小麦参试材料在15个农艺性状上具有丰富的多样性,通过综合评价筛选出了21份综合性状表现优良的冬小麦材料,可以从中选育出具有高产潜力的冬小麦新品种,同时为冬小麦杂交选育提供了优良的亲本资源和理论参考。142-3-3-1(D38)、141-1-8-1(D35)和2012Y-01-6-1(D43)3份材料较对照陇麦844综合表现优良,产量高。 展开更多
关键词 冬小麦 农艺性状 相关分析 主成分分析 聚类分析
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匝道合流交通场景下自动驾驶汽车安全性测试评价方法
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作者 李文礼 李中峰 +1 位作者 李超 易帆 《汽车工程学报》 2024年第3期354-362,共9页
针对高速匝道交通场景提出了一种基于自然驾驶数据的自动驾驶汽车安全性评价方法。通过分析合流区冲突特征,建立碰撞时间(Time to Collision,TTC)模型、后侵占时间(Post Encroachment Time,PET)模型、最小安全换道距离(Minimum Safe Spa... 针对高速匝道交通场景提出了一种基于自然驾驶数据的自动驾驶汽车安全性评价方法。通过分析合流区冲突特征,建立碰撞时间(Time to Collision,TTC)模型、后侵占时间(Post Encroachment Time,PET)模型、最小安全换道距离(Minimum Safe Spacing,MSS)交通冲突指标计算模型来确定安全性评价指标,利用模糊聚类自然驾驶指标数据确定指标阈值范围,搭建自动驾驶汽车仿真测试试验,应用层间相关性的重要性准则权重分配方法和灰色关联评分模型,计算得到不同控制算法下自动驾驶汽车安全性的综合评价得分。结果表明,被试车辆驾驶行为与理想驾驶行为在各安全性指标的关联度分布明显,计算总体关联度,得分可以直观说明不同自动驾驶系统的综合安全性能。 展开更多
关键词 自动驾驶汽车 安全性评价 模糊聚类分析 灰色关联度
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