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Time Slice Analysis Method Based on OTCA Used in fMRI Weak Signal Function Extraction
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作者 罗森林 黎力 +1 位作者 张新丽 张铁梅 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期443-447,共5页
The original temporal clustering analysis (OTCA) is an effective technique for obtaining brain activation maps when the timing and location of the activation are completely unknown, but its deficiency of sensitivity i... The original temporal clustering analysis (OTCA) is an effective technique for obtaining brain activation maps when the timing and location of the activation are completely unknown, but its deficiency of sensitivity is exposed in processing brain activation signal which is relatively weak. The time slice analysis method based on OTCA is proposed considering the weakness of the functional magnetic resonance imaging (fMRI) signal of the rat model. By dividing the stimulation period into several time slices and analyzing each slice to detect the activated pixels respectively after the background removal, the sensitivity is significantly improved. The inhibitory response in the hypothalamus after glucose loading is detected successfully with this method in the experiment on rat. Combined with the OTCA method, the time slice analysis method based on OTCA is effective on detecting when, where and which type of response will happen after stimulation, even if the fMRI signal is weak. 展开更多
关键词 functional magnetic resonance imaging (fMRI) time cluster analysis (TCA) original temporal clustering analysis (OTCA) time slice analysis method
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Analysis of the medication rules of the national patent compound for the treatment of functional dyspepsia 被引量:2
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作者 Shan-Shan Yang Xue-Zhi Zhang +3 位作者 Hui Ye Shao-Dong Hao Xin Deng Hui-Xia Xiao 《Journal of Hainan Medical University》 2021年第3期52-58,共7页
Objective:Based on data mining software,applying frequent itemsets,association rules,hierarchical clustering,complex networks and other data mining methods to analyze the usage and compatibility of traditional Chinese... Objective:Based on data mining software,applying frequent itemsets,association rules,hierarchical clustering,complex networks and other data mining methods to analyze the usage and compatibility of traditional Chinese medicine(TCM)patent compound for functional dyspepsia.Method:Use the Chinese patent database to search the compound for the treatment of functional dyspepsia,exclude traditional Chinese medicine extracts,single drugs,combined use of Chinese and Western medicines,etc.,screen the patented compound of TCM,establish an Excel data table,and apply data mining software to The data is subjected to frequency statistics,association rules,cluster analysis and complex network analysis.Result:A total of 238 prescriptions for functional dyspepsia were screened.The four qi of the drugs were mainly warm and calm,the five flavors were mainly sweet and spicy,and the spleen and stomach were the main meridians.The top 10 Chinese medicines with higher frequency are Shanzha、Chenpi、Gancao、Maiya、Jineijin、Fuling、Baizhu、Shenqu、Houpo、Banxia;frequent itemsets show that the drugs are mainly compatible with qi and spleen,qi and digestion;association rules The analysis shows that the common drug pairs used in the treatment of functional dyspepsia include Chenpi-Shanzha、Maiya-Shanzha、Jineijin-Shanzha,etc.;cluster analysis found that there are 4 types of drugs for functional dyspepsia,mainly including drugs for regulating qi-flowing for harmonizing stomach,drugs for soothing liver and promoting Qi,drugs for eliminating food and resolving accumulation,drugs for benefiting qi and strengthening spleen;the 22-flavor Chinese medicine in the core drug network,the core compatibility is mainly to eliminate stagnation and spleen.Conclusion:Data mining research provides a reference for the clinical treatment of functional dyspepsia and the development of TCM formulas;Clinical treatment of functional dyspepsia should grasp the basic principles of strengthening vital energy and eliminating pathogenic factors to benefit qi,strengthen the spleen,and eliminate food.It is a basic treatment method,taking into account the methods of regulating qi-flowing for harmonizing stomach,soothing the liver and relieving depression,relieving dampness and dampness,and combining the specific conditions of patients with syndrome differentiation and treatment. 展开更多
关键词 functional dyspepsia Aata mining Association rules cluster analysis Core network
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Unsupervised Functional Data Clustering Based on Adaptive Weights
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作者 Yutong Gao Shuang Chen 《Open Journal of Statistics》 2023年第2期212-221,共10页
In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be direc... In recent years, functional data has been widely used in finance, medicine, biology and other fields. The current clustering analysis can solve the problems in finite-dimensional space, but it is difficult to be directly used for the clustering of functional data. In this paper, we propose a new unsupervised clustering algorithm based on adaptive weights. In the absence of initialization parameter, we use entropy-type penalty terms and fuzzy partition matrix to find the optimal number of clusters. At the same time, we introduce a measure based on adaptive weights to reflect the difference in information content between different clustering metrics. Simulation experiments show that the proposed algorithm has higher purity than some algorithms. 展开更多
关键词 functional Data Unsupervised Learning clustering functional Principal Component analysis Adaptive Weight
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基于加权Ripley's K-function的多尺度景观格局分析——以江苏盐城滨海湿地为例 被引量:13
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作者 张东菊 左平 邹欣庆 《生态学报》 CAS CSCD 北大核心 2015年第8期2703-2711,共9页
以1987,1992,1997,2002,2007年的遥感影像为例,首次尝试使用加权Ripley's K-function的多尺度格局分析方法,计算了20年来景观异质性在江苏盐城滨海湿地的时间变化和空间分布趋势。通过对研究区的样带划分以及景观类型的点状化处理,... 以1987,1992,1997,2002,2007年的遥感影像为例,首次尝试使用加权Ripley's K-function的多尺度格局分析方法,计算了20年来景观异质性在江苏盐城滨海湿地的时间变化和空间分布趋势。通过对研究区的样带划分以及景观类型的点状化处理,建立滨海湿地样带图层和1987—2007年间各类型景观的点格局数据库,从而分析滨海湿地不同类型景观的空间聚集特征变化。基于加权Ripley's K-function的计算表明,在各级空间尺度和时间变化上,各类型湿地的斑块都呈现出空间聚集分布状态,且1987年以来,不同湿地类型的聚集空间特征尺度和空间分布强度均出现了大幅的增减变化,除互花米草滩之外的自然湿地的聚集空间特征尺度和强度都有明显下降甚至少到无法被检测到,而人工湿地却呈现聚集特征尺度和强度的双增长,且该聚集程度有逐渐增强的趋势。分析表明,既考虑样点的空间位置信息又考虑样点分布范围的加权Ripley's K-function方法能很好地表征湿地景观在多尺度上的变异,且与传统空间景观指数等分析方法的结论在一定程度上保持一致。 展开更多
关键词 盐城滨海湿地 景观空间格局 多尺度空间聚集分析 加权Ripley’s K-function 空间特征尺度 空间分布强度
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Derringer desirability and kinetic plot LC-column comparison approach for MS-compatible lipopeptide analysis 被引量:1
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作者 Matthias D’Hondt Frederick Verbeke +3 位作者 Sofie Stalmans Bert Gevaert Evelien Wynendaele Bart De Spiegeleer 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第3期173-182,共10页
Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antit... Lipopeptides are currently re-emerging as an interesting subgroup in the peptide research field, having historical applications as antibacterial and antifungal agents and new potential applications as antiviral, antitumor, immune-modulating and cell-penetrating compounds. However, due to their specific structure, chromatographic analysis often requires special buffer systems or the use of trifluoroacetic acid, limiting mass spectrometry detection. Therefore, we used a traditional aqueous/acetonitrile based gradient system, containing 0.1% (m/v) formic acid, to separate four pharmaceutically relevant lipopeptides (polymyxin B1, caspofungin, daptomycin and gramicidin A1), which were selected based upon hierarchical cluster analysis (HCA) and principal component analysis (PCA).In total, the performance of four different C18 columns, including one UPLC column, were evaluated using two parallel approaches. First, a Derringer desirability function was used, whereby six single and multiple chromatographic response values were rescaled into one overall D-value per column. Using this approach, the YMC Pack Pro C18 column was ranked as the best column for general MS-compatible lipopeptide separation. Secondly, the kinetic plot approach was used to compare the different columns at different flow rate ranges. As the optimal kinetic column performance is obtained at its maximal pressure, the length elongation factor λ(Pmax/Pexp) was used to transform the obtained experimental data (retention times and peak capacities) and construct kinetic performance limit (KPL) curves, allowing a direct visual and unbiased comparison of the selected columns, whereby the YMC Triart C18 UPLC and ACE C18 columns performed as best. Finally, differences in column performance and the (dis)advantages of both approaches are discussed. 展开更多
关键词 LIPOPEPTIDE Hierarchical cluster analysis (HCA) Principal component analysis (PCA) LC-MS Kinetic plot Derringer desirability function
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Ant colony ATTA clustering algorithm of rock mass structural plane in groups 被引量:9
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作者 李夕兵 王泽伟 +1 位作者 彭康 刘志祥 《Journal of Central South University》 SCIE EI CAS 2014年第2期709-714,共6页
Based on structural surface normal vector spherical distance and the pole stereographic projection Euclidean distance,two distance functions were established.The cluster analysis of structure surface was conducted by ... Based on structural surface normal vector spherical distance and the pole stereographic projection Euclidean distance,two distance functions were established.The cluster analysis of structure surface was conducted by the use of ATTA clustering methods based on ant colony piles,and Silhouette index was introduced to evaluate the clustering effect.The clustering analysis of the measured data of Sanshandao Gold Mine shows that ant colony ATTA-based clustering method does better than K-mean clustering analysis.Meanwhile,clustering results of ATTA method based on pole Euclidean distance and ATTA method based on normal vector spherical distance have a great consistence.The clustering results are most close to the pole isopycnic graph.It can efficiently realize grouping of structural plane and determination of the dominant structural surface direction.It is made up for the defects of subjectivity and inaccuracy in icon measurement approach and has great engineering value. 展开更多
关键词 rock mass discontinuity cluster analysis ant colony ATTA algorithm distance function Silhouette index
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Urban Economic Cluster Template and Its Dynamics of Beijing,China 被引量:3
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作者 YANG Zhenshan LIANG Jinshe CAI Jianming 《Chinese Geographical Science》 SCIE CSCD 2014年第6期740-750,共11页
Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well de... Economic clusters have been a central focus of current urban and regional research, policies and practices. However, a methodology to identify and analyze policy-relevant economic cluster dynamics is still not well developed. Based on input-output(I-O) data of 1987, 1992, 1997, 2002 and 2007 of Beijing, this article presents an adapted principle component analysis for identifying the evolution of local economic cluster patterns. This research addresses the changes of economic interaction of industries with complementary and common activities over time. The identified clusters provide an insight into the reality of economic development in a diversifying urban economy: the increasing importance of services and the growing interaction between service and manufacturing industries. Our method therefore provides the analysts with a better understanding of the emergence, disappearance and development of economic clusters citywide. The results could be used to assist monitoring urban economic development and designing more practical urban economic strategies. 展开更多
关键词 economic clusters industrial linkages urban economic dynamics functional analysis INPUT-OUTPUT BEIJING China
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Bioinformatics Analysis of Genes and Pathways of CD11b^(+)/Ly6C^(intermediate)Macrophages after Renal Ischemia-Reperfusion Injury 被引量:2
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作者 Dong SUN Xin WAN +5 位作者 Bin-bin PAN Qing SUN Xiao-bing JI Feng ZHANG Hao ZHANG Chang-chun CAO 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2018年第1期70-77,共8页
Renal ischemia-reperfusion injury(IRI)is a major cause of acute kidney injury(AKI),which could induce the poor prognosis.The purpose of this study was to characterize the molecular mechanism of the functional changes ... Renal ischemia-reperfusion injury(IRI)is a major cause of acute kidney injury(AKI),which could induce the poor prognosis.The purpose of this study was to characterize the molecular mechanism of the functional changes of CD11 b^(+)/Ly6 C^(intermediate)macrophages after renal IRI.The gene expression profiles of CD11 b^(+)/Ly6 C^(intermediate)macrophages of the sham surgery mice,and the mice 4 h,24 h and 9 days after renal IRI were downloaded from the Gene Expression Omnibus database.Analysis of m RNA expression profiles was conducted to identify differentially expressed genes(DEGs),biological processes and pathways by the series test of cluster.Protein-protein interaction network was constructed and analysed to discover the key genes.A total of 6738 DEGs were identified and assigned to 20 model profiles.DEGs in profile 13 were one of the predominant expression profiles,which are involved in immune cell chemotaxis and proliferation.Signet analysis showed that Atp5 a1,Atp5 o,Cox4 i,Cdc42,Rac2 and Nhp2 were the key genes involved in oxidation-reduction,apoptosis,migration,M1-M2 differentiation,and proliferation of macrophages.RPS18 may be an appreciate reference gene as it was stable in macrophages.The identified DEGs and their enriched pathways investigate factors that may participate in the functional changes of CD11 b^(+)/Ly6 C^(intermediate)macrophages after renal IRI.Moreover,the vital gene Nhp2 may involve the polarization of macrophages,which may be a new target to affect the process of AKI. 展开更多
关键词 renal ischemia-reperfusion injury MACROPHAGE differentially expressed genes series test of cluster functional enrichment analysis protein-protein interaction
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Displacement reconstruction and strain refinement of clustering-based homogenization 被引量:1
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作者 Lei Zhang Shaoqiang Tang 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第6期343-349,共7页
Recently proposed clustering-based methods provide an efficient way for homogenizing heterogeneous materials,yet without concerning the detailed distribution of the mechanical responses.With coarse fields of the clust... Recently proposed clustering-based methods provide an efficient way for homogenizing heterogeneous materials,yet without concerning the detailed distribution of the mechanical responses.With coarse fields of the clustering-based methods as an initial guess,we develop an iteration strategy to fastly and accurately resolve the displacement,strain and stress based on the Lippmann-Schwinger equation,thereby benefiting the local mechanical analysis such as the detection of the stress concentration.From a simple elastic case,we explore the convergence of the method and give an instruction for the selection of the reference material.Numerical tests show the efficiency and fast convergence of the reconstruction method in both elastic and hyper-elastic materials. 展开更多
关键词 HOMOGENIZATION Self-consistent clustering analysis Lippmann-Schwinger equation Green’s function
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Development of slope mass rating system using K-means and fuzzy c-means clustering algorithms 被引量:1
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作者 Jalali Zakaria 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期959-966,共8页
Classification systems such as Slope Mass Rating(SMR) are currently being used to undertake slope stability analysis. In SMR classification system, data is allocated to certain classes based on linguistic and experien... Classification systems such as Slope Mass Rating(SMR) are currently being used to undertake slope stability analysis. In SMR classification system, data is allocated to certain classes based on linguistic and experience-based criteria. In order to eliminate linguistic criteria resulted from experience-based judgments and account for uncertainties in determining class boundaries developed by SMR system,the system classification results were corrected using two clustering algorithms, namely K-means and fuzzy c-means(FCM), for the ratings obtained via continuous and discrete functions. By applying clustering algorithms in SMR classification system, no in-advance experience-based judgment was made on the number of extracted classes in this system, and it was only after all steps of the clustering algorithms were accomplished that new classification scheme was proposed for SMR system under different failure modes based on the ratings obtained via continuous and discrete functions. The results of this study showed that, engineers can achieve more reliable and objective evaluations over slope stability by using SMR system based on the ratings calculated via continuous and discrete functions. 展开更多
关键词 SMR based on continuous functions Slope stability analysis K-means and FCM clustering algorithms Validation of clustering algorithms Sangan iron ore mines
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44份西瓜种质资源苗期耐盐性综合评价 被引量:6
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作者 马肖静 刘勇鹏 +5 位作者 尚文凯 高宁宁 张涛 朴凤植 王永 赵卫星 《中国瓜菜》 CAS 北大核心 2024年第3期45-53,共9页
以44份西瓜种质为试验材料,设置0(CK)和150 mmol·L^(-1)NaCl 2个处理水平,测定不同西瓜种质幼苗的15项指标。以15项指标的耐盐系数作为耐盐性评价依据,运用相关性分析、主成分分析、隶属函数值法、聚类分析等多元分析方法进行综合... 以44份西瓜种质为试验材料,设置0(CK)和150 mmol·L^(-1)NaCl 2个处理水平,测定不同西瓜种质幼苗的15项指标。以15项指标的耐盐系数作为耐盐性评价依据,运用相关性分析、主成分分析、隶属函数值法、聚类分析等多元分析方法进行综合评价。通过主成分分析将15个单项指标转换为4个相互独立的综合指标,累计贡献率为71.10%;以耐盐系数为基础进行聚类分析,筛选出10个高度耐盐、21个中度耐盐、13个弱耐盐西瓜种质资源。采用隶属函数法进行综合评价,排名前5的种质分别是HY-91、DQ-308、W19-15、HY-73、W19-10,归为聚类分析中的第一类,属于强耐盐性品种。 展开更多
关键词 西瓜 苗期 耐盐性 隶属函数 聚类分析
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Human wetland dependency and socio-economic evaluation of wetland functions through participatory approach in rural India
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作者 Malabika BISWAS Nihar R.SAMAL +1 位作者 Pankaj K.ROY Asis MAZUMDAR 《Water Science and Engineering》 EI CAS 2010年第4期467-479,共13页
Wetlands are an important source of natural resources upon which rural economies depend. They have increasingly been valuable for their goods and services, and the intrinsic ecological value they provide to local popu... Wetlands are an important source of natural resources upon which rural economies depend. They have increasingly been valuable for their goods and services, and the intrinsic ecological value they provide to local populations, as well as people living outside the periphery of the wetlands. Stakeholders' participation is essential to the protection and preservation of wetlands because it plays a very important role economically as well as ecologically in the wetland system. The objective of this study was to determine whether gender, educational status, mouzas (which are constituents of a block according to the land reform of the West Bengal Government in India), and wetland functions have any influence on the annual income of the local community. Considering a floodplain wetland in rural India, the focus was extended to recognize the pattern of wetland functions according to the nature of people's involvement through cluster analysis of the male and female populations. Using the statistical software R-2.8.1, an ANOVA (analysis of variance) table was constructed. Since the p value (significance level) was lower than 0.05 for each case, it can be concluded that gender, educational status, mouzas, and wetland functions have a significant influence on annual income. However, S-PLUS-2000 was applied to obtain a complete scenario of the pattern of wetland functions, in terms of involvement of males and females, through cluster analysis. The main conclusion is that gender, educational status, mouzas, and wetland functions have significant impacts on annual income, while the pattern of occupation of the local community based on wetland functions is completely different for the male and female populations. 展开更多
关键词 wetland dependency socio-economic evaluation wetland functions rural India cluster analysis
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THE CLASSIFICATION OF INDUSTRIAL FUNCTION OF CHINESE CITIES (INCLUDING ATTACHED COUNTIES)
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作者 Zhou Yixing Roy Bradshaw 《Journal of Geographical Sciences》 SCIE CSCD 1990年第2期12-33,共22页
Represents the first attempt to classify all of China’s295 cities in terms of industrial functions,using 1984 data.Within the framework of economic base theory of urban development,three elements are defined as speci... Represents the first attempt to classify all of China’s295 cities in terms of industrial functions,using 1984 data.Within the framework of economic base theory of urban development,three elements are defined as specialized branch,functional intensity and functional scale.The method used here is based on a combination of the three elements.A number of techniques tried made it possible to base the classification on a composite measure,consisting of the Ward’s Error Method of hierarchical cluster analysis and a supplementary application of Nelson measure.The 295 cities have been grouped into three categories with 19 subcategories and 54 functional groups.The distribution of cities in most of the subcategories are displayed on 8 maps. 展开更多
关键词 INDUSTRY urban functional classification cluster analysis
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大凉山地区不同马铃薯品种产量和营养品质的综合评价 被引量:1
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作者 汤云川 张庆沛 +9 位作者 冯焱 淳俊 王暄 陈汉 樊红柱 袁星 李倩 杨洪 邓海艳 陈涛 《中国蔬菜》 北大核心 2024年第6期89-100,共12页
为筛选出适宜四川大凉山地区种植的马铃薯品种,对14个马铃薯品种的12个产量与营养品质指标进行测定,并结合主成分分析、隶属函数法、系统聚类分析对马铃薯产量和品质表现进行综合评价。结果表明,单株结薯数、单薯鲜质量、单株块茎鲜质... 为筛选出适宜四川大凉山地区种植的马铃薯品种,对14个马铃薯品种的12个产量与营养品质指标进行测定,并结合主成分分析、隶属函数法、系统聚类分析对马铃薯产量和品质表现进行综合评价。结果表明,单株结薯数、单薯鲜质量、单株块茎鲜质量、单产、还原糖含量的变异系数均超过30%;单株块茎鲜质量与单薯鲜质量、单产和蛋白质含量呈极显著正相关,干物质含量与淀粉含量、蛋白质含量呈极显著正相关,单薯鲜质量与VC含量、锌含量呈显著负相关,蛋白质含量与钾含量呈极显著负相关;主成分分析结果表明,12个指标可用4个主成分来表示,方差累积贡献率达到86.040%。进一步采用隶属函数法和系统聚类分析将14个品种分为3类,筛选出6个综合表现较优的品种,分别为川凉薯10号、青薯9号、川芋50、川凉芋13、云薯108、川芋22号。 展开更多
关键词 大凉山地区 马铃薯 主成分分析 隶属函数法 聚类分析
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Relation between Family Functioning and Quality of Life among Family Caregivers of Patients with Terminal Cancer Hospitalized in General Wards
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作者 Miki Morishita-Kawahara Takuya Kawahara Kiyoko Kamibeppu 《Open Journal of Nursing》 2020年第12期1233-1240,共8页
Caring for a patient with terminal cancer poses difficulties for family caregivers. Although families of patients with cancer have been classified by type, little is known about the relation between family functioning... Caring for a patient with terminal cancer poses difficulties for family caregivers. Although families of patients with cancer have been classified by type, little is known about the relation between family functioning and quality of life (QOL) in family caregivers. This study aimed to develop a typology of family functioning in family caregivers of patients with terminal cancer and then examine the relation between the family functioning and QOL of family caregivers. From December 2013 to August 2014, fifty-one family caregivers of patients with terminal cancer were recruited at three hospitals in Tokyo, Japan. Perceptions of family functioning were assessed with the Family Relationship Index, and its three subscores were classified into three groups by cluster analysis. Caregivers’ QOL was measured with the Caregiver Quality of Life Index-Cancer. The average total FRI score among 51 caregivers was 8.5 (SD = 2.8). Family functioning was categorized into three clusters: supportive (n = 12), communicative (n = 30), or conflictive (n = 8). Their QOL was categorized into two groups: the communicative group, with relatively high confliction, showed high QOL comparable to the supportive group. Family functioning in the families of patients with terminal cancer hospitalized in general wards was not good. For improving the QOL of family caregivers, it may be important for the family members to express their feelings and distress if they have conflicts. 展开更多
关键词 cluster analysis Family Caregivers of Terminal Cancer Patients Family functioning General Wards Quality of Life
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青海高原栽培羊肚菌营养和氨基酸特征分析及综合评价 被引量:2
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作者 陈万超 李文 +5 位作者 陈辉 张津京 唐利华 吴迪 张忠 杨焱 《食用菌学报》 CSCD 北大核心 2024年第2期64-75,共12页
为探究高原地区栽培羊肚菌(Morchella spp.)的营养品质,以海拔3 570 m栽培的3个六妹羊肚菌(M. sextelata)品种(M6、HB-8和HB-5)子实体(高原栽培羊肚菌)为主,对比同地域野生样品及湖北栽培的相同品种样品(平原栽培羊肚菌),分析粗蛋白、... 为探究高原地区栽培羊肚菌(Morchella spp.)的营养品质,以海拔3 570 m栽培的3个六妹羊肚菌(M. sextelata)品种(M6、HB-8和HB-5)子实体(高原栽培羊肚菌)为主,对比同地域野生样品及湖北栽培的相同品种样品(平原栽培羊肚菌),分析粗蛋白、粗脂肪、粗多糖、灰分、粗纤维、矿质元素、维生素和氨基酸等营养成分的差异。结果显示:当品种相同时,与平原栽培羊肚菌相比,高原栽培羊肚菌的粗蛋白、粗脂肪含量显著上升,灰分含量显著下降,粗纤维含量显著降低(除M6外);K和Fe含量均显著降低;维生素B6、维生素B2、维生素B9、维生素D、维生素E含量显著降低,维生素B1含量显著升高;总氨基酸含量、总必需氨基酸含量及总必需氨基酸占总氨基酸含量均显著上升。高原栽培羊肚菌的必需氨基酸指数(IAAI)明显高于平原栽培羊肚菌,更接近于FAO/WHO标准蛋白,且其生物价(BV)更高。关联性分析表明,羊肚菌中维生素B6、维生素B9(叶酸)、维生素D和维生素E含量与总必需氨基酸含量呈极显著负相关,维生素B6与粗多糖含量存在显著正相关。热图-聚类分析结果表明,高原栽培羊肚菌蛋白营养价值突出,而平原栽培羊肚菌矿质元素含量较高。营养品质综合评价结果表明,高原栽培羊肚菌样品评分结果明显均优于相同品种的平原栽培样品。 展开更多
关键词 羊肚菌 高原 营养评价 氨基酸评价 主成分分析 隶属函数
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芦竹属菌草腋芽萌发期耐盐性评价
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作者 蔡杨星 林冬梅 +5 位作者 曹秀明 刘斌 林辉 罗海凌 刘凤山 林占熺 《福建农林大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期541-548,共8页
【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜... 【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜质量、发芽势、发芽率、发芽指数和活力指数)进行测定。利用模糊隶属函数法和聚类分析法对供试品种的耐盐性进行综合评价。【结果】与对照组相比,在150 mmol·L^(-1) NaCl胁迫下,所有供试品种的发芽势均降低,芽长、根长、芽鲜质量和根鲜质量都减小;除LZ_NO.1、LZ_NO.3和LZ_NO.7外,其他品种的发芽率均下降;活力指数受盐胁迫的影响最大。基于各指标耐盐系数隶属函数值的临近度对12个品种进行聚类分析,结果表明:LZ_NO.1、LZ_NO.3和LZ_NO.7为一类,属高耐盐型;LZ_NO.2、LZ_NO.4和LZ_NO.6为一类,属盐敏感型。【结论】腋芽萌发期耐盐性较强的芦竹属菌草品种为LZ_NO.1、LZ_NO.3和LZ_NO.7;根据活力指数可判定芦竹属菌草品种的质量优劣。 展开更多
关键词 芦竹属菌草 腋芽萌发 耐盐性 隶属函数分析法 聚类分析
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50份加工型辣椒DH系苗期耐低温弱光综合评价
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作者 王春萍 李怡斐 +5 位作者 张世才 杨小苗 段敏杰 雷开荣 黄启中 黄任中 《中国蔬菜》 北大核心 2024年第6期48-54,共7页
以前期利用花药培养技术创制的50份加工型辣椒DH系为试验材料,以SPAD值、F_(v)/F_(m)、根系直径、茎叶干质量、根系干质量、整株干质量和根冠比7个指标的耐低温弱光指数为评价指标,采用模糊隶属函数和聚类分析法对其进行耐低温弱光综合... 以前期利用花药培养技术创制的50份加工型辣椒DH系为试验材料,以SPAD值、F_(v)/F_(m)、根系直径、茎叶干质量、根系干质量、整株干质量和根冠比7个指标的耐低温弱光指数为评价指标,采用模糊隶属函数和聚类分析法对其进行耐低温弱光综合评价。结果表明:50份DH系的耐低温弱光模糊隶属函数综合指数范围在0.20~0.76之间,聚类分析可将其分为两大类,根据耐低温弱光指数特点和模糊隶属函数综合指数可确定第Ⅱ类有7份DH系为耐低温弱光材料,即H201605-8、H201604-4-1、H201612-4-1、H201605-7、H201612-4、H201605-34和H201604-18。50份加工型辣椒DH系间耐低温弱光性差异较大,可作为相关机理研究的试验材料;筛选出的7份耐低温弱光DH系为培育适合设施栽培的优良辣椒新品种提供了材料基础,也为定向培育抗非生物逆境辣椒种质新材料提供了参考。 展开更多
关键词 辣椒 DH系 低温弱光 模糊隶属函数分析 聚类分析
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11个柠檬砧木种质对淹水胁迫的生理响应及耐涝性评价
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作者 余智城 林秀香 +2 位作者 林秋金 谢晓清 陈振东 《中国南方果树》 北大核心 2024年第5期18-23,共6页
探究不同砧木种质植株对淹水胁迫的生理响应及耐涝性,可为柠檬耐涝砧木选育及抗涝机理研究提供理论依据。以11个柠檬砧木种质当年生实生苗为供试材料,设置正常水分管理(对照)和持续淹水处理,通过测定相对电导率、叶绿素、可溶性蛋白、... 探究不同砧木种质植株对淹水胁迫的生理响应及耐涝性,可为柠檬耐涝砧木选育及抗涝机理研究提供理论依据。以11个柠檬砧木种质当年生实生苗为供试材料,设置正常水分管理(对照)和持续淹水处理,通过测定相对电导率、叶绿素、可溶性蛋白、可溶性糖、丙二醛含量和过氧化氢酶活性等指标研究各种质对淹水胁迫的生理响应,进一步通过主成分分析和隶属函数法对各种质的耐涝性进行综合评价,最后根据综合评价值对砧木种质进行聚类分析。结果表明,淹水胁迫后,不同砧木种质的相对电导率均增加,叶绿素和可溶性蛋白含量均降低,可溶性糖、丙二醛含量和过氧化氢活性在不同种质中呈现升高或降低的变化趋势。在供试种质中,白[木黎]檬1号、酸橙和香橙强耐涝,泰国香橼和白[木黎]檬2号较强耐涝,大果红[木黎]檬、酸柚、酸桔和小青柠中等耐涝,红柠檬和粗柠檬不耐涝。 展开更多
关键词 柠檬 砧木 耐涝性 主成分分析 隶属函数法 综合评价
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基于模糊评判的无线传感器网络簇间数据转发算法
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作者 周海飞 芦翔 胡春芬 《传感技术学报》 CAS CSCD 北大核心 2024年第6期1067-1072,共6页
由于无线传感器网络在簇间数据转发过程中消耗能量较大、转发效率低,导致数据在转发过程中容易失效。为此,提出基于模糊评判的无线传感器网络簇间数据转发算法。建立无线传感器网络模型和通信模型,明确节点的运行方式和转发数据所消耗... 由于无线传感器网络在簇间数据转发过程中消耗能量较大、转发效率低,导致数据在转发过程中容易失效。为此,提出基于模糊评判的无线传感器网络簇间数据转发算法。建立无线传感器网络模型和通信模型,明确节点的运行方式和转发数据所消耗的能量,构建模糊综合评判模型,选取梯形隶属度函数计算传感器节点的相似度和活跃度,找出最佳转发节点,完成数据转发任务。仿真结果表明,所提算法的第一个节点死亡轮数和网络失效轮数最高为167和178,在仿真轮数达到1000轮时,该算法剩余的网络能量和节点平均能量分别为4 J和0.01 J,证明所提算法在数据转发过程中可消耗最少的能量,高效率地完成数据转发任务。 展开更多
关键词 无线传感器网络 簇间数据转发 模糊评判 梯形隶属度函数 节点活跃度
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