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Using Normal Form of Idempotent Matrices over Finite Local Ring Z/p^kZ to Construct Cartesian Authentication Codes 被引量:1
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作者 赵辉芳 南基洙 《Northeastern Mathematical Journal》 CSCD 2007年第2期123-131,共9页
In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probab... In this paper, we determine the normal forms of idempotent matrices for similarity over finite local rings Z/p^kZ, from which we construct a Cartesian authentication code and compute its size parameters and the probabilities of successful impersonation and substitution attack under the hypothesis that the cecoding rules are chosen according to a uniform probability distribution. 展开更多
关键词 idempotent matrix finite local ring Cartesian authentication code
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Linear Maps Preserving Idempotency of Products of Matrices on Upper Triangular Matrix Algebras
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作者 QI JING Ji GUO-XING 《Communications in Mathematical Research》 CSCD 2009年第3期253-264,共12页
Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple ... Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple Jordan products of two matrices. 展开更多
关键词 linear map matrix idempotent product of two matrices triple Jordan product of two matrices
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稀疏L型阵中基于压缩感知的角度估计方法
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作者 苏龙 谷绍湖 邓桂萍 《太赫兹科学与电子信息学报》 2024年第3期345-352,共8页
利用二级Nested阵来构建稀疏L型阵列,针对此阵列,提出了基于压缩感知的角度估计方法。该方法通过计算接收数据的自相关协方差矩阵并向量化,然后进行重排序和去冗余,得到虚拟阵列的入射角信息。该虚拟阵列的长度远远大于实际物理阵列的长... 利用二级Nested阵来构建稀疏L型阵列,针对此阵列,提出了基于压缩感知的角度估计方法。该方法通过计算接收数据的自相关协方差矩阵并向量化,然后进行重排序和去冗余,得到虚拟阵列的入射角信息。该虚拟阵列的长度远远大于实际物理阵列的长度,因而相比同物理阵元的均匀L型阵,阵列孔径和自由度明显增大。最后利用正交匹配追踪技术对虚拟阵列的l1范数约束问题进行求解,并完成二维角度的配对。计算机仿真表明,所提算法具有更高的信源分辨力,并且在高信噪比、高快拍数、大角度间隔条件下,具有更好的估计性能。 展开更多
关键词 稀疏l型阵 虚拟阵列 压缩感知 正交匹配追踪算法
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严格对角占优L-矩阵的预条件Jacobi迭代法
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作者 许云霞 雷学红 《高师理科学刊》 2024年第1期1-4,共4页
讨论了一种预条件Jacobi迭代法,理论上证明了系数矩阵为严格对角占优L-矩阵时,所给预条件子加快了Jacobi迭代法的收敛速度.通过三个数值实例验证了系数为严格对角占优L-矩阵预条件Jacobi迭代法的有效性.
关键词 预条件 JACOBI迭代法 严格对角占优l-矩阵 谱半径
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Effects of the Syzygium aromaticum L. extract on antioxidation and inhibition of matrix metalloproteinase in human dermal fibroblast 被引量:1
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作者 Da Eun Kim Yeon Sil Hwang +3 位作者 Bo Yoon Chang Dae Sung Kim Hyoung Kwon Cho Sung Yeon Kim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2019年第2期53-59,共7页
Objective: To investigate cosmetic potential of Syzygium aromaticum L.(S. aromaticum L.) and to determine its antioxidant and anti-wrinkling effects. Methods: Using highperformance liquid chromatography, eugenol compo... Objective: To investigate cosmetic potential of Syzygium aromaticum L.(S. aromaticum L.) and to determine its antioxidant and anti-wrinkling effects. Methods: Using highperformance liquid chromatography, eugenol component was quantitated. The antioxidant activity of S. aromaticum L. was analyzed by 2,2-diphenyl-1-picrylhydrazyl radical scavenging and superoxide dismutase like activities. To determine cell viability, elastase and matrix metalloproteinase-1(MMP-1) activity, human dermal fibroblasts(HS68) were treated with S. aromaticum L. The inhibitory effect of S. aromaticum L. on tumor necrosis factor alpha induced MMPs expression in HS68 was analyzed by realtime-PCR. Results: The eugenol content was confirmed in S. aromaticum L. S. aromaticum L. was observed to have high 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and superoxide dismutase like activity. S. aromaticum L. had no cytotoxicity against the HS68 and dose-dependently increased elastase inhibition. Moreover, S. aromaticum L. significantly decreased MMP-1 content and inhibited gene levels of MMP-1, MMP-2, MMP-3 and MMP-9. Conclusions: The findings suggest that S. aromaticum L. has great potential as a cosmeceutical ingredient with antioxidant and antiwrinkling effects. 展开更多
关键词 SYZYGIUM aromaticum l Antioxidant ANTI-AGING ElASTASE matrix metalloproteinase-1
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Minimum Cycle of Row Vector of a Generalized Circulant Fuzzy Matrix
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作者 冼国荣 陈卓荣 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第1期104-110, ,共7页
In this paper,we intreduce the concept and discuss the properties of minimum cycle of row vector in a generalized circulant Fuzzy matrix. We present a new expression for circulant Fuzzy matrix,and discuss some propert... In this paper,we intreduce the concept and discuss the properties of minimum cycle of row vector in a generalized circulant Fuzzy matrix. We present a new expression for circulant Fuzzy matrix,and discuss some properties of the idempotent elements of the semigroup of generalized circulant Fuzzy matrixes in connection with minimum cycle of row vector. 展开更多
关键词 generalized circulant Fuzzy matrix SEMIGROUP VECTOR CYClE idempotent element
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重型颅脑损伤病人血清NF-L和TIMP-2水平变化及临床意义 被引量:1
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作者 鲍彤 李静 +2 位作者 孔为园 杨磊 王鹏飞 《中国临床神经外科杂志》 2023年第5期307-310,共4页
目的探讨重型颅脑损伤(TBI)病人血清神经丝蛋白轻链多肽(NF-L)、组织基质金属蛋白酶抑制因子-2(TIMP-2的水平变化及临床意义。方法2019年8月~2021年8月前瞻性收集重型TBI共122例,采用酶联免疫吸附试验检查入院血清NF-1和TIMP-2水平;伤后... 目的探讨重型颅脑损伤(TBI)病人血清神经丝蛋白轻链多肽(NF-L)、组织基质金属蛋白酶抑制因子-2(TIMP-2的水平变化及临床意义。方法2019年8月~2021年8月前瞻性收集重型TBI共122例,采用酶联免疫吸附试验检查入院血清NF-1和TIMP-2水平;伤后6个月,应用GOS评分评估预后,其中4~5分为预后良好,1~3分为预后不良。结果伤后6个月,预后良好72例,预后不良50例。预后不良组血清NF-L以及TIMP-2水平明显高于预后良好组(P<0.05)。入院血清NF-L水平(r=-0.585)、TIMP-2水平(r=-0.542)与入院GCS评分呈明显负相关(P<0.05)。多因素Cox回归分析显示,血清NF-L、TIMP-2水平增高是重型TBI伤后6个月预后不良的独立危险因素(P<0.05)。ROC曲线分析显示血清NF-L1≥54.60 pg/ml联合血清TIMP-2≥42.59 ng/ml预测重型TBI伤后6个月预后不良的曲线下面积为0.854(95%CI 0.789~0.919),灵敏度为82.0%,特异度为70.8。结论重型TBI病人血清NF-L、TIMP-2水平明显增高,是伤后6个月预后不良的危险因素;两者联合应用对病人预后具有较高的预测价值。 展开更多
关键词 重型颅脑损伤 神经丝蛋白轻链多肽(NF-l) 组织基质金属蛋白酶抑制因子-2(TIMP-2) 血清 预后
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Dynamic culture of a thermosensitive collagen hydrogel as an extracellular matrix improves the construction of tissue-engineered peripheral nerve 被引量:3
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作者 Lanfeng Huang Rui Li +5 位作者 Wanguo Liu Jin Dai Zhenwu Du Xiaonan Wang Jianchao Ma Jinsong Zhao 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第14期1371-1378,共8页
Tissue engineering technologies offer new treatment strategies for the repair of peripheral nerve injury, hut cell loss between seeding and adhesion to the scaffold remains inevitable. A thermosensitive collagen hydro... Tissue engineering technologies offer new treatment strategies for the repair of peripheral nerve injury, hut cell loss between seeding and adhesion to the scaffold remains inevitable. A thermosensitive collagen hydrogel was used as an extracellular matrix in this study and combined with bone marrow mesenchymal stem cells to construct tissue-engineered peripheral nerve composites in vitro. Dynamic culture was performed at an oscillating frequency of 0.5 Hz and 35° swing angle above and below the horizontal plane. The results demonstrated that bone marrow mesenchymal stem cells formed membrane-like structures around the poly-L-lactic acid scaffolds and exhibited regular alignment on the composite surface. Collagen was used to fill in the pores, and seeded cells adhered onto the poly-L-lactic acid fibers. The DNA content of the bone marrow mesenchymal stem cells was higher in the composites constructed with a thermosensitive collagen hydrogel compared with that in collagen I scaffold controls. The cellular DNA content was also higher in the thermosensitive collagen hydrogel composites constructed with the thermosensitive collagen hydrogel in dynamic culture than that in static culture. These results indicate that tissue-engineered composites formed with thermosensitive collagen hydrogel in dynamic culture can maintain larger numbers of seeded cells by avoiding cell loss during the initial adhe-sion stage. Moreover, seeded cells were distributed throughout the material. 展开更多
关键词 nerve regeneration peripheral nerve biomaterials extracellular matrix TISSUEENGINEERING nerve scaffold bone marrow mesenchymal stem cells thermosensitive collagen hydrogel poly-l-lactic acid dynamic culture NSFC grant neural regeneration
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含缺陷陶瓷基复合材料L形构件承载性能及破坏过程
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作者 周俊辰 耿谦 +1 位作者 段玉斌 王栋梁 《复合材料科学与工程》 CAS 北大核心 2023年第6期37-43,共7页
本文基于图像重构技术,构建了陶瓷基复合材料代表性体积单胞及L形构件的有限元模型,预测了陶瓷基复合材料的弹性模量。通过试验和数值仿真,研究了强制拉伸位移作用下L形构件的承载性能及破坏过程。结果表明,在缺陷对构件承载性能的影响... 本文基于图像重构技术,构建了陶瓷基复合材料代表性体积单胞及L形构件的有限元模型,预测了陶瓷基复合材料的弹性模量。通过试验和数值仿真,研究了强制拉伸位移作用下L形构件的承载性能及破坏过程。结果表明,在缺陷对构件承载性能的影响规律方面,仿真结果与试验结果一致性较好,两者相差约10%。L形构件内侧圆角区域主要承受拉伸作用,外侧主要承受压缩作用。内侧缺陷影响试样的承载性能,承载性能随缺陷面积的增大而降低;而外侧缺陷会影响试样的破坏过程,微观缺陷会扩展为宏观破坏,以材料脱层为主。本文的研究方法与结果可为陶瓷基复合材料典型构件承载性能的测试与分析提供参考。 展开更多
关键词 陶瓷基复合材料 l形构件 承载性能 破坏过程 强度分析 准静态加载
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THE CHARACTERISTIC POLYNOMIAL ANDEIGENVALUES OF FINILE RIODAN MATRIXTHE CHARACTERISTIC POLYNOMIAL ANDEIGENVALUES OF FINILE RIODAN MATRIX
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作者 周持中 《岳阳师范学院学报(自然科学版)》 2000年第3期1-6,共6页
In this paper we deal with the characteristic polynomial of finite Riodan matix. We giveseveral forms of its explicit expressions. Its applications to combinatorial identities, specially to F-Lidentities, are stated.
关键词 riodan matrix CHARACTERISTIC POlYNOMIAl F-l IDENTITY
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Improvement of foreign gene expression in transgenic rice(Oryza sativa L.)by matrix attachment regions(MARs)
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作者 MA Bingtian, Li Xugang , Li Ping, ZHU Zhen , and ZHOU Kaida , Rice Res Inst, Sichuan Agri Univ, Wenjiang 611130 Sichuan Agri Biotechnology Engineering Res Center, Wenjiang 611130 Inst of Genetics & Developmental Biology, the Chinese Academy of Sciences, Beijing 100101, China 《Chinese Rice Research Newsletter》 2002年第3期7-7,共1页
Matrix attachment regions or matrix associated regions (MARs) were special DNA sequences in chromatin of eukaryotic cells that tightly associated with the nuclear matrix or scaffold in vitro after a combination of nuc... Matrix attachment regions or matrix associated regions (MARs) were special DNA sequences in chromatin of eukaryotic cells that tightly associated with the nuclear matrix or scaffold in vitro after a combination of nuclease digestion and extraction. They were also called scaffold attachment regions(SARs) . It was found that MARs could improve the expression level and the stability of foreign genes in transgenic plants. The reason might be that a transgene flanked by MARs was transmitted into the plant cells, the MARs would attach the nuclear 展开更多
关键词 by matrix attachment regions Improvement of foreign gene expression in transgenic rice MARS Oryza sativa l GENE
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A novel procedure for identifying a hybrid QTL-allele system for hybrid-vigor improvement, with a case study in soybean(Glycine max)yield
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作者 Jinshe Wang Jianbo He +1 位作者 Jiayin Yang Junyi Gai 《The Crop Journal》 SCIE CSCD 2023年第1期177-188,共12页
“Breeding by design” for pure lines may be achieved by construction of an additive QTL-allele matrix in a germplasm panel or breeding population, but this option is not available for hybrids, where both additive and... “Breeding by design” for pure lines may be achieved by construction of an additive QTL-allele matrix in a germplasm panel or breeding population, but this option is not available for hybrids, where both additive and dominance QTL-allele matrices must be constructed. In this study, a hybrid-QTL identification approach, designated PLSRGA, using partial least squares regression(PLSR) for model fitting integrated with a genetic algorithm(GA) for variable selection based on a multi-locus, multi-allele model is described for additive and dominance QTL-allele detection in a diallel hybrid population(DHP). The PLSRGA was shown by simulation experiments to be superior to single-marker analysis and was then used for QTL-allele identification in a soybean DPH yield experiment with eight parents. Twenty-eight main-effect QTL with 138 alleles and nine QTL × environment QTL with 46 alleles were identified, with respective contributions of 61.8% and 23.5% of phenotypic variation. Main-effect additive and dominance QTL-allele matrices were established as a compact form of the DHP genetic structure. The mechanism of heterosis superior-to-parents(or superior-to-parents heterosis, SPH) was explored and might be explained by a complementary locus-set composed of OD+(showing positive over-dominance, most often), PD+(showing positive partial-to-complete dominance, less often) and HA+(showing positive homozygous additivity, occasionally) loci, depending on the parental materials. Any locus-type, whether OD+, PD + and HA+, could be the best genotype of a locus. All hybrids showed various numbers of better or best genotypes at many but not necessarily all loci, indicating further SPH improvement. Based on the additive/dominance QTL-allele matrices, the best hybrid genotype was predicted, and a hybrid improvement approach is suggested. PLSRGA is powerful for hybrid QTL-allele detection and cross-SPH improvement. 展开更多
关键词 Breeding by design Diallel hybrid population PlSRGA(partial least squares regression via genetic algorithm) QTl-allele matrix of additive/dominance effect Simulation experiment Soybean[Glycine max(l.)Merr.]
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糖尿病性心肌病患者血清PDK4,DECR1和MMP1表达水平及临床价值研究
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作者 马美娟 宋荟琴 +1 位作者 张国安 黄晓燕 《现代检验医学杂志》 CAS 2024年第5期130-134,共5页
目的探讨血清丙酮酸脱氢酶激酶同工酶4(pyruvate dehydrogenase kinase isoenzyme 4,PDK4),2,4-二烯酰辅酶A还原酶1(2,4-dienoyl coenzyme A reductase 1,DECR1)及基质金属蛋白酶1(matrix metalloproteinase 1,MMP1)的联合检测在糖尿病... 目的探讨血清丙酮酸脱氢酶激酶同工酶4(pyruvate dehydrogenase kinase isoenzyme 4,PDK4),2,4-二烯酰辅酶A还原酶1(2,4-dienoyl coenzyme A reductase 1,DECR1)及基质金属蛋白酶1(matrix metalloproteinase 1,MMP1)的联合检测在糖尿病性心肌病(diabetic cardiomyopathy,DCM)诊断、临床分级和病情预后中的应用价值。方法选取2021年10月~2023年10月陕西省人民医院收治的126例糖尿病性心肌病(DCM组)患者及120例单纯糖尿病非心肌病患者(对照组),采用酶联免疫吸附法(ELISA)测定血清中PDK4,DECR1及MMP1蛋白表达水平,评估这三个检测指标在DCM中的诊断、临床分级和病情预后中的应用价值。结果DCM组患者血清PDK4(131.38±10.20 pg/ml),DECR1(152.06±12.57 pg/ml)及MMP1(40.27±4.02μg/ml)蛋白表达水平与对照组(82.69±8.17 pg/ml,86.14±9.55 pg/ml,17.77±0.98μg/ml)相比均明显升高,差异具有统计学意义(t=36.24,47.63,12.29,均P<0.001)。DCM组患者血清PDK4,DECR1及MMP1蛋白表达水平与NYHA心功能分级相关,随等级升高其蛋白表达水平均明显升高,差异具有统计学意义(F=24.12,30.04,12.66,均P<0.001);DCM组中重度组患者与轻度组患者比较,血清PDK4(164.92±1.35pg/ml vs 122.48±8.78pg/ml),DECR1(192.17±9.11pg/ml vs124.36±10.83pg/ml)及MMP1(84.44±7.38μg/ml vs 39.41±3.05μg/ml)蛋白表达水平均显著增高,差异具有统计学意义(t=26.33,47.12,15.41,均P<0.001)。血清PDK4,DECR1及MMP1三项联合检测DCM准确度(χ^(2)=18.23,21.37,22.07)、特异度(χ^(2)=9.72,13.43,15.12)、灵敏度(χ^(2)=12.07,16.07,17.55)与单项检测对比均明显升高,差异具有统计学意义(均P<0.05),且ROC曲线分析结果显示联合检测的AUC高达0.955,明显高于单项检测(Z=16.67,17.09,20.44,均P<0.05)。结论血清PDK4,DECR1及MMP1与DCM诊断、临床分级及病情预后有一定关联,三者联合检测有助于DCM的鉴别诊断。 展开更多
关键词 糖尿病性心肌病 丙酮酸脱氢酶激酶同工酶4 2 4-二烯酰辅酶A还原酶1 基质金属蛋白酶1
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广义m对合矩阵和(m,l)幂等矩阵的充要条件及应用 被引量:3
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作者 吕洪斌 杨忠鹏 +2 位作者 冯晓霞 陈梅香 黄丽琴 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2012年第6期1069-1074,共6页
由矩阵多项式的秩性质,给出广义m对合矩阵与(m,l)幂等矩阵的充要条件,推广并改进了m对合矩阵和m幂等矩阵的相应结论.
关键词 广义m对合矩阵 (m l)幂等矩阵 矩阵秩 充要条件
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胃癌中幽门螺杆菌L型感染与MIF、MMP9、VEGF表达的关系 被引量:46
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作者 欧玉荣 康敏 +3 位作者 周蕾 承泽农 唐素兰 于东红 《南方医科大学学报》 CAS CSCD 北大核心 2014年第2期180-187,共8页
目的探讨胃癌组织中幽门螺杆菌L型(Hp-L)感染与巨噬细胞移动抑制因子(MIF)、基质金属蛋白酶-9(MMP-9)和血管内皮生长因子(VEGF)表达之间的相互关系及临床意义。方法应用免疫组织化学染色法及革兰染色检测80例胃癌组织及50例癌旁正常组织... 目的探讨胃癌组织中幽门螺杆菌L型(Hp-L)感染与巨噬细胞移动抑制因子(MIF)、基质金属蛋白酶-9(MMP-9)和血管内皮生长因子(VEGF)表达之间的相互关系及临床意义。方法应用免疫组织化学染色法及革兰染色检测80例胃癌组织及50例癌旁正常组织中Hp-L感染情况,同时检测上述组织中MIF、MMP9、VEGF蛋白的表达;运用RT-PCR及Western blotting法检测30例新鲜胃癌组织及相应切缘组织中MIFmRNA及MIF、MMP9、VEGF蛋白的表达。结果 80例胃癌组织中经免疫组化和革兰染色同时阳性病例有57例,与对照组相比具有显著性差异(71.25%vs 14%,P<0.05);胃癌组织中Hp-L阳性组中MIF、MMP9、VEGF蛋白表达阳性率高于Hp-L阴性组(P<0.05),且Hp-L感染与MIF、MMP9和VEGF表达均呈正相关关系(r=0.598,r=0.292,r=0.341,P<0.05)。30例胃癌新鲜组织中MIF-mRNA表达(1.583±0.177)高于对照组(1.407±0.078),两者差异具有显著性(t=3.729,P=0.001);Western blotting法检测MIF、MMP9、VEGF蛋白在胃癌组织中的表达显著高于癌旁正常组织;胃癌组织中MIF、MMP9均与肿瘤浸润深度及淋巴结转移有关,VEGF蛋白表达与肿瘤浸润深度有关(P<0.05)。结论 Hp-L型感染是促进胃癌的侵袭与转移的重要因素之一,其机制与上调胃癌组织中MIF、MMP9、VEGF表达有关。 展开更多
关键词 胃癌 幽门螺杆菌 细菌l 巨噬细胞移动抑制因子 基质金属蛋白酶-9 血管内皮生长因子 matrix METAllOPROTEINASE 9
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(m,l)幂等矩阵的代数等价与正交的一些性质 被引量:5
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作者 陈梅香 林维 杨忠鹏 《数学研究》 CSCD 2012年第1期58-65,共8页
应用数域上(m,l)幂等矩阵与m幂等矩阵的关系,得到了数域上(m,l)幂等矩阵的l次方幂的代数等价、相似和特征多项式相等是互为确定的结论,由此推广改进了数域上m幂等矩阵的代数等价与正交性的相应结果.
关键词 (m l)幂等矩阵 代数等价 矩阵相似 特征多项式
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本质(m,l)幂等矩阵的特征研究 被引量:4
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作者 杨忠鹏 陈梅香 郭文静 《数学研究》 CSCD 2011年第1期86-94,共9页
若有最小正整数m使当m>l时A^m=A^l成立,称A为本质(m,l)幂等矩阵.本文讨论了本质(m,l)幂等矩阵的特征.作为应用,给出了本质m对合、本质m幂等矩阵的等价刻画,讨论了最小多项式与本质(m,l)幂等矩阵的一些关系.
关键词 本质(m l)幂等矩阵 矩阵秩 JORDAN标准形 最小多项式
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一类单圈图的Laplacian谱刻画 被引量:6
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作者 卢鹏丽 王旭柱 陈作汉 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2012年第7期851-854,共4页
针对哪些图可由它们的谱刻画这一问题,在lollipop图和图H(n;q,n1,n2)的基础上定义了一类新的图类,符号表示为H(n;q,n1,n2,n3),它是通过在圈Cq的同一个顶点上连接3条悬挂路Pn1、Pn2、Pn3而得到的顶点数为n的单圈图.首先,证明了此图类中,... 针对哪些图可由它们的谱刻画这一问题,在lollipop图和图H(n;q,n1,n2)的基础上定义了一类新的图类,符号表示为H(n;q,n1,n2,n3),它是通过在圈Cq的同一个顶点上连接3条悬挂路Pn1、Pn2、Pn3而得到的顶点数为n的单圈图.首先,证明了此图类中,如果2个图形不同构,那么它们必定具有不同的Laplacian谱.在此结论的基础上,证明了图H(n;q,n1,n2,n3)可由它的Laplacian谱刻画. 展开更多
关键词 lAPlACIAN矩阵 laplacian特征多项式 l-同谱 l-谱
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Clifford矩阵半群 被引量:5
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作者 陈大亮 朱用文 《烟台大学学报(自然科学与工程版)》 CAS 北大核心 2010年第4期251-255,共5页
运用Clifford半群中格林关系的特殊性,结合一些矩阵在一定条件下可同时对角化的方法,研究了任意数域上的矩阵构成的Clifford半群的结构,给出了Clifford矩阵半群中格林D类的一些一般刻画,并完全刻画了低阶矩阵构成的Clifford矩阵半群的结... 运用Clifford半群中格林关系的特殊性,结合一些矩阵在一定条件下可同时对角化的方法,研究了任意数域上的矩阵构成的Clifford半群的结构,给出了Clifford矩阵半群中格林D类的一些一般刻画,并完全刻画了低阶矩阵构成的Clifford矩阵半群的结构,最后从已知的Clifford矩阵半群出发构造了一类新的Clifford矩阵半群. 展开更多
关键词 ClIFFORD半群 矩阵半群 格林关系 幂等元 特征值
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基于L曲线法的电容层析成像正则化参数优化 被引量:18
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作者 王化祥 何永勃 朱学明 《天津大学学报》 EI CAS CSCD 北大核心 2006年第3期306-309,共4页
电容层析成像(ECT)系统的不适定性问题严重影响重建图像质量,为此必须减小灵敏度矩阵的条件数.以Tikhonov正则化和后验策略为基础,从灵敏度矩阵广义逆的角度阐述了L曲线法并设置滤波函数,建立极小化泛函及L曲线图,最终确定正则参数.... 电容层析成像(ECT)系统的不适定性问题严重影响重建图像质量,为此必须减小灵敏度矩阵的条件数.以Tikhonov正则化和后验策略为基础,从灵敏度矩阵广义逆的角度阐述了L曲线法并设置滤波函数,建立极小化泛函及L曲线图,最终确定正则参数.仿真实验表明,L曲线法具有较强的抗噪声性能和较快的收敛速度,明显改善了ECT系统的重构图像质量. 展开更多
关键词 电容层析成像 不适定性 正则化 l曲线法 灵敏度矩阵
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