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Study on Selection and Application of New Matrixes for Floating Tobacco Seedlings 被引量:2
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作者 黄石旺 刘正日 +13 位作者 高春洋 周向平 杨全柳 王锡春 张芳 袁芳 肖小波 朱军 莫凯明 吴亮亮 胡述泉 石江波 魏丽丽 许剑波 《Agricultural Science & Technology》 CAS 2013年第9期1271-1279,共9页
[Objective] This study aimed to verify the effects of new matrixes on tobacco seedlings on floating platform or field, and their effects on tobacco leaf yield and quality. [Method] The ratio of peat: carbonized rice ... [Objective] This study aimed to verify the effects of new matrixes on tobacco seedlings on floating platform or field, and their effects on tobacco leaf yield and quality. [Method] The ratio of peat: carbonized rice hull: perlite: sand in the four new matrixes was 10∶40∶30∶20, 20∶40∶10∶30, 20∶40∶30∶10 and 20∶50∶10∶20, marked as T1, T2, T3 and T4, respectively. The ratio in control matrix was 35∶40∶25∶0. [Result]In formulas T1, T2, T3 and T4, the peat consumption was reduced by 70.1%,41.5%, 41.5%, and 41.5% respectively, which saved 12.5%, 23.1%, 8.2% and 12.8%of the cost. The new matrixes can effectively increase the seedling emergence rate of tobacco. The quality and duration of seedlings in float system with new matrixes showed no difference from those of control matrix. The values of output using the new matrixes were 323.10, 92.25, 39.30 and 2 250.60 Yuan/hm2higher than that of the control. Besides, the proportion of the first- and second-rate tobacco leaves was also improved. [Conclusion] These four new matrixes can be widely applied to raise seedling in a float system, and T4 is the best choice. 展开更多
关键词 TOBACCO Seedling in a float system New matrixes
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Risks Matrixes Risks Assessment Tools of Small and Medium-Sized Enterprises: The Case of Latvia
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作者 Inga Jansone Irina Voronova 《Journal of Modern Accounting and Auditing》 2014年第5期575-582,共8页
The enterprises need to assess the risk dynamic of financial instability and its impact on small and medium-sized enterprises' development, because it is important for enterprises to extend commercial activity and to... The enterprises need to assess the risk dynamic of financial instability and its impact on small and medium-sized enterprises' development, because it is important for enterprises to extend commercial activity and to open a new structural subdivision. We have researched types of risks, their identification, classification, and assessment possibilities in activities of small and medium-sized enterprises. We have used our own algorithm of identification, classification, and assessment of enterprises' risks. The goal of this research is to study the economic and financial risks' impact on small and medium-sized enterprises' development in Latvia. For study purpose, we have carried out the questionnaire of representative small and medium-sized enterprises about the economic and financial risks' impact on enterprises' development in Latvia. We have created classification of Latvian services sectors' economic and financial risks in the period from 2011 to 2012. Those risks have been included in the questionnaire. The risks matrix is a quantitative assessment tool of risks. We have created Latvian service sector economic and financial risks matrix. We have arranged risks by their sizes of possible losses for enterprises. For each risk has been assessed its probability of realization. We have created Latvian accommodations (hotel) and food services technological process risks map. Several parts of the risk map (segments) make it possible to assess each type of the risk separately in its segment. Risks matrix can be used to choose enterprises' strategy of risk management. Enterprise's strategy of risk management is developed by analysing zones of risk level. 展开更多
关键词 classification of risks risks assessment risks matrixes questionnaire of small and medium-sizedenterprises
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Rheological Behavior of the Matrixes of Bauxite-Based Castables 被引量:2
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作者 YEFangbao RigaudM. 《China's Refractories》 CAS 2003年第3期7-12,共6页
Rheplpgy of castables is greatly affected and controlled by rheological behavior of their matrix. In this work ,the rheological properties of bauxite-based castable matrix have been studied. The effects of super-fine ... Rheplpgy of castables is greatly affected and controlled by rheological behavior of their matrix. In this work ,the rheological properties of bauxite-based castable matrix have been studied. The effects of super-fine silica and alumina addition , water/ cement ratio, dispersants and bauxite particle-size on viscosity, shear rate and shear stress of the slur-ries have been investigated . Based on these results, the range of optimum composition of the matrix with good rheological behavior has been obtained. 展开更多
关键词 Rheblogy BAUXITE Gastahle MATRIX
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Optical spectroscopy and crystal-field strength of Cr^(3+) in various solid matrixes 被引量:2
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作者 XIA Haiping WANG Jinhao WANG Hongyin ZHANG Jianli ZHANG Yuepin XU Tiefeng 《Rare Metals》 SCIE EI CAS CSCD 2006年第1期51-57,共7页
The Cr^3+:BeAl2O4 crystal, Cr^3+:LiNbO3 crystal, and ZnO-Al2O3-SiO2 glass-ceramic were obtained by the Czochralski technique, Bridgman method, and melting processing, respectively. The optical absorption and emiss... The Cr^3+:BeAl2O4 crystal, Cr^3+:LiNbO3 crystal, and ZnO-Al2O3-SiO2 glass-ceramic were obtained by the Czochralski technique, Bridgman method, and melting processing, respectively. The optical absorption and emission spectra of the above Cr^3+-incorporated solid-state materials were recorded. The technical parameters for growing high-quality Cr^3+:BeAl2O4 and Cr^3+:LINbO3 crystals were obtained. The results indicate that the optical absorption and fluorescence spectra of Cr^3+ show quite a few differences in various matrixes. The sharp line emissions were observed in the Cr^3+:BeAl2O4 and Cr^3+:LiNbO3 crystals. The crystal-field parameters (Dq) for Cr^3+. in different matrixes were calculated from their corresponding spectra. It is indicated that Cr^3+:BeAl2O4 and Cr^3+:LiNbO3 belong to the high-field site crystal, while the Cr^3+ ZnO-Al2O3-SiO2 glass and glass-ceramic belong to the weak-field site crystal. 展开更多
关键词 special functional inorganic materials optical spectroscopy optical measurement Cr^3+ ion matrix
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The construction and combined operation for fuzzy consistent matrixes 被引量:2
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作者 姚敏 沈斌 骆建华 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期27-31,共5页
Fuzziness is one of the general characteristics of human thinking and objective things. Introducing fuzzy techniques into decision-making yields very good results. Fuzzy consistent matrix has many excellent characteri... Fuzziness is one of the general characteristics of human thinking and objective things. Introducing fuzzy techniques into decision-making yields very good results. Fuzzy consistent matrix has many excellent characteristics, especially cen- ter-division transitivity conforming to the reality of the human thinking process in decision-making. This paper presents a new approach for creating fuzzy consistent matrix from mutual supplementary matrix in fuzzy decision-making. At the same time, based on the distance between individual fuzzy consistent matrix and average fuzzy consistent matrix, a kind of combined opera- tion for several fuzzy consistent matrixes is presented which reflects most opinions of experienced experts. Finally, a practical example shows its flexibility and practicability further. 展开更多
关键词 Fuzzy consistent matrix Fuzzy consistent relation Compound operation
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Microstructure inheritance of matrixes of SiC_(f)/Ti6242 composites from precursor wire coatings byα+βphase field consolidation 被引量:2
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作者 Wang-Teng-Fei Fang Xu Huang +3 位作者 Hu Li Min-Juan Wan Mao Wen Hao Huang 《Rare Metals》 SCIE EI CAS CSCD 2021年第12期3676-3684,共9页
SiC_(f)/Ti composite owns the attractive advantages of lightweight and excellent high-temperature performance,which make it have great significance to the development of aerospace industry.However,the complicated fabr... SiC_(f)/Ti composite owns the attractive advantages of lightweight and excellent high-temperature performance,which make it have great significance to the development of aerospace industry.However,the complicated fabrication route and novel architecture of SiC_(f)/Ti composite bring about more difficulties for controlling its microstructure.In this work,the method of regulating the structure and performance of the composite matrix by adjusting the characteristics of the precursor wire was explored.The physical vapor deposition(PVD)method was applied to fabricate precursor wires.Ti6242 coatings with bamboo leaf-shaped grains and chrysanthemumshaped grains were deposited on SiC fibers by changing the PVD condition.It is found that the original structure of the Ti6242 coating of precursor wire has significant impact on the microstructure of the composite matrix after hot isostatic pressing(HIP).The matrix transformed from the Ti6242 coating with bamboo leaf-shaped grains exhibits equiaxed grain structure.While the other matrix has a columnar crystal structure,and the inside of the columnar crystal inherits the original chrysanthemum-shaped structure.The columnar crystal matrix has lower hardness and modulus than the equiaxed grain matrix. 展开更多
关键词 SiC_(f)/Ti composite physical vapor deposition(PVD) Ti6242 coating HIP consolidation Matrix
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Ranking Method for Complementary Judgment Matrixes with Fuzzy Numbers Based on Hausdorff Metric Distance 被引量:1
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期458-461,共4页
A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary jud... A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary judgment matrixes given by a decider group whose members have various weights, the expert's information was aggregated first by means of simple weight average(SWA) method and Bonissone calculational method. Hence a matrix including all the experts' preference information was got. Then the matrix' column members were added up and the fuzzy evaluation values of the alternatives were got. Lastly, the Hausdorff metric distance and fuzzy compromise decision approach were used to rank the fuzzy evaluation values and then the ranking values of all the alternatives were got. Because exact numbers and triangular fuzzy numbers could all be transformed into trapezoidal fuzzy numbers, the method developed can rank complementary judgment matrixes with trapezoidal fuzzy numbers, triangular fuzzy numbers and exact numbers as well. An illustrative example is also given to verify the developed method and to demonstrate its feasibility and practicality. 展开更多
关键词 complementary judgment matrix trapezoidal fuzzy number Bonissone calculational method fuzzy compromise decision approach Hausdorff metric distance
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NEGATIVE REGULATORY ROLE OF SOMATOSTATIN AND OCTREOTIDE IN EXTRACELLULAR MATRIXES METABOLISM OF RAT HEPATIC STELLATE CELL
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作者 潘勤 李定国 +2 位作者 陆汉明 张文竹 徐芹芳 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2008年第2期71-76,共6页
Objective To investigate the regulatory effects of somatostatin (SST) and octreotide (OCT) on the extracellular matrixes (ECM) metabolism of rat hepatic stellate cells (HSCs). Methods Being treated with different conc... Objective To investigate the regulatory effects of somatostatin (SST) and octreotide (OCT) on the extracellular matrixes (ECM) metabolism of rat hepatic stellate cells (HSCs). Methods Being treated with different concentrations of SST or OCT, the mRNA levels of collage type I, III and the expression of collagen, matrix metalloproteinase-1(MMP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1) in activated HSCs were assessed by in situ hybridization (ISH), 3H-proline incorporation and immunocytochemistry, respectively. In addition, levels of hyaluronic acid (HA), laminin (LM), and procollagen type III (PCIII) in the culture supernatant of HSCs were also detected by means of enzyme-linked immunosorbent assay (ELISA). ResultsBoth SST and OCT markedly down-regulated the transcription of collagen type I, III in activated HSCs within the range of 10-6-10-7 mol/L and 10-5-10-7 mol/L, respectively (P<0.05). SST-treated groups of 10-6-10-7 mol/L and OCT-treated groups of 10-5-10-7 mol/L also demonstrated statistically decreased production of collagen, HA, LM, PCIII in a dose-dependent way (P<0.05). Furthermore, HSCs cocultured with SST (10-6 mol/L) or OCT (10-5-10-6 mol/L) exhibited TIMP-1 levels much lower than that of normal control (P<0.05), which resulted in an elevated ratio of MMP/TIMP. Conclusion SST and its analog may play a negative regulatory role in the ECM metabolism of HSCs. Their effect may be benefit for prevention and therapy of hepatic fibrosis. 展开更多
关键词 somatostatin octreotide extracellular matrix hepatic stellate cell
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The Effect of Bioceramic Composite Extracellular Matrixes Used to Repair Bone Deficiency on Relevant Blood Biochemical Indices
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作者 ZHU Ming-hua ZENG Yi +3 位作者 WANG Lin SUN Tao PENG Qiang YE Chang-ning 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第2期47-54,92,共9页
At the base of experimental animal model construction of bone defect in New Zealand rabbit, the promoting repair effect of bioactive ceramics on bone defect as well as its machanism was studied through testing body mi... At the base of experimental animal model construction of bone defect in New Zealand rabbit, the promoting repair effect of bioactive ceramics on bone defect as well as its machanism was studied through testing body mineral elements, enzymes related to bone morphogenetic proteins and some biochemical indexes. Refering to some documents, materials of TCP, CHA and HA were combined and TCP/BMP/ TCP-β1 and CHA/BMP/ TCP-β1,HA/BMP/ TCP-β1 composite materials were made. All kinds of them were implanted into the radial defect site of rabbit, respectively. The chosen blood indexes (Ca, P, ALP, GGT, AST, ALT, TPA, BUN and Cr) were tested by colorimetry, speed rate and bromocresol green testing methods. No abnormal effects were found in any animal after operation. Serum concentrations of Ca, P and ALP were increased with the length of time in all groups of the three kinds of composite material, mixed material and pure materials. The increases in composite material groups were more significant (P<0.05). Comparison of the three kinds of material showed TCP>CHA>HA. There was a tendency of increased TPA and decreased BUN with the length of time. There was no significant difference between the composite material groups and pure material group (P>0.05). The three kinds of bioactive ceramics composed of extracellular matrix could increase the serum concentrations of Ca and P and activity of ALP after being implanted into defect bone and showed some repairing capacity. This provided a new area of machanism study of bone defect repair by biomaterials. 展开更多
关键词 bioactive ceramics extracellular matrix biochemical indexes bone defect
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MG63 Osteoblast-like Cells Growth Behaviour on Carbon/Carbon Composites with Different Carbon Matrixes
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作者 ZHANG Leiei LI Hejun +3 位作者 LI Kezhi ZHAO Xueni WU Heng CAO Sheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第2期303-308,共6页
During the process that implant materials are used for bone replacement,the cell responses to implant materials determine the long-term stability of bone replacement.The microstructure of implant materials is consider... During the process that implant materials are used for bone replacement,the cell responses to implant materials determine the long-term stability of bone replacement.The microstructure of implant materials is considered as a critical factor that influences the cell responses.Carbon/Carbon composites(C/C composites)are novel implant materials,but there are few reports on the effect of their microstructure,especially the carbon matrixes and holes,on cell behavior.In this paper,C/C composites with different carbon matrixes are prepared by chemical vapor infiltration and pressure impregnation carbonization technique,respectively.The structure of holes is analyzed.The cell responses to C/C composites with different carbon matrixes are evaluated with MG63 osteoblast-like cells.The morphologies of MG63 osteoblast-like cells on the surface of C/C composites,especially in the holes are assessed by scanning electron microscope,and cell proliferation behavior is evaluated by 3-[4,5-dimethylthiozol-2-yl]-2,5-diphenyltetrazolium bromide(MTT)assay.The results show that MG63 osteoblast-like cells have a lamellar morphology with similar sizes and spreading areas as well as the same proliferation behaviors for C/C composites with different carbon matrixes.Carbon matrix shows unapparent influence on the cell growth behavior.Besides,MG63 osteoblast-like cells have various interactions with the holes of C/C composites.The cells stride over the holes with 6~8μm in size,and connect with each other or grow along the curvature wall of the holes with a size of 30-40μm;the cells present three-dimensional morphologies inside the holes and display circular shapes along the ridge of the holes.Diverse cell-material interactions are found according to the size and position of the holes,which provides theoretical foundation for the microstructure design of clinical C/C composites. 展开更多
关键词 Carbon/Carbon composite matrix osteoblast growth behavior microstructure
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Discrete Time Mean-variance Analysis with Singular Second Moment Matrixes and an Exogenous Liability 被引量:1
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作者 Wen Cai CHEN Zhong Xing YE 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第4期565-576,共12页
We apply the dynamic programming methods to compute the analytical solution of the dynamic mean-variance optimization problem affected by an exogenous liability in a multi-periods market model with singular second mom... We apply the dynamic programming methods to compute the analytical solution of the dynamic mean-variance optimization problem affected by an exogenous liability in a multi-periods market model with singular second moment matrixes of the return vector of assets. We use orthogonai transformations to overcome the difficulty produced by those singular matrixes, and the analytical form of the efficient frontier is obtained. As an application, the explicit form of the optimal mean-variance hedging strategy is also obtained for our model. 展开更多
关键词 mean-variance analysis exogenous liability singular second moment matrixes orthogonal transformations dynamic programming methods
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Predictive model based on magnetic resonance imaging for chemotherapy response in colorectal cancer:Toward a radiologic biopsy approach
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作者 Ilya D Klabukov Anna Smirnova +2 位作者 Irina Kondrasheva Denis S Baranovskii Elena Yatsenko 《World Journal of Gastrointestinal Oncology》 2026年第1期296-299,共4页
We read with great interest the investigation of Kang et al related the applications of the multiparametric magnetic resonance imaging-based predictive model for assessing chemotherapy efficacy in colorectal cancer pa... We read with great interest the investigation of Kang et al related the applications of the multiparametric magnetic resonance imaging-based predictive model for assessing chemotherapy efficacy in colorectal cancer patients with gene mutations.The authors focused on decision-making based on the integration of tumor differentiation,signal intensity ratio,margin distance,and magnetic resonance imaging-detected lymph node metastasis.Indeed,these multiparameter predictive models could also be used for diagnosis as an alternative to invasive tissue examination methods.However,progress in this field enables us to shift the paradigm to radiology biopsies,particularly given the nonlinear effects of various radiation sources. 展开更多
关键词 BIOPSY Cancer Extracellular matrix ONCOLOGY RADIOLOGY Tumor microenvironment TUMORIGENESIS
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Cancer cell-dependent increase in senescence-like populationsfollowing exosome treatment:The role of extracellular matrix andcellular glycocalyx
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作者 Ilya D Klabukov Anastas Kisel +2 位作者 Elena Yatsenko Yana Sulina Denis S Baranovskii 《World Journal of Stem Cells》 2026年第1期108-111,共4页
We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-l... We read with the great interest the study by Ababneh et al in which inducedmesenchymal stem cell-derived exosomes were shown to exhibit a stronger andmore sustained anti-proliferative effect by inducing a senescence-like state withoutapoptosis.The results obtained by the authors highlight the features of theeffects of senescent drift induction in surrounding tissues.In the light of thesefindings,the role of the properties of extracellular matrix and cellular glycocalyxin responses of human tumors to therapy remain uninvestigated.These extracellularbarriers appear to be significant obstacles to effective cancer therapy,especiallyin relation to the use of unique properties of tumor microenvironment forthe immunotherapy-resistant cancer treatment. 展开更多
关键词 Cancer Extracellular matrix GLYCOCALYX EXOSOMES Extracellular vesicles Tumor microenvironment
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Porcine decellularized nerve matrix hydrogel attenuates neuroinflammation after peripheral nerve injury by inhibiting the TLR4/MyD88/NF-κB axis
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作者 Rui Li Jianquan Liu +7 位作者 Liuxun Li Guotian Luo Xinrong Yuan Shichao Shen Yongpeng Shi Jianlong Wu Bin Yan Lei Yang 《Neural Regeneration Research》 2026年第3期1222-1235,共14页
Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological prop... Peripheral nerve injury causes severe neuroinflammation and has become a global medical challenge.Previous research has demonstrated that porcine decellularized nerve matrix hydrogel exhibits excellent biological properties and tissue specificity,highlighting its potential as a biomedical material for the repair of severe peripheral nerve injury;however,its role in modulating neuroinflammation post-peripheral nerve injury remains unknown.Here,we aimed to characterize the anti-inflammatory properties of porcine decellularized nerve matrix hydrogel and their underlying molecular mechanisms.Using peripheral nerve injury model rats treated with porcine decellularized nerve matrix hydrogel,we evaluated structural and functional recovery,macrophage phenotype alteration,specific cytokine expression,and changes in related signaling molecules in vivo.Similar parameters were evaluated in vitro using monocyte/macrophage cell lines stimulated with lipopolysaccharide and cultured on porcine decellularized nerve matrix hydrogel-coated plates in complete medium.These comprehensive analyses revealed that porcine decellularized nerve matrix hydrogel attenuated the activation of excessive inflammation at the early stage of peripheral nerve injury and increased the proportion of the M2 subtype in monocytes/macrophages.Additionally,porcine decellularized nerve matrix hydrogel negatively regulated the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB axis both in vivo and in vitro.Our findings suggest that the efficacious anti-inflammatory properties of porcine decellularized nerve matrix hydrogel induce M2 macrophage polarization via suppression of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB pathway,providing new insights into the therapeutic mechanism of porcine decellularized nerve matrix hydrogel in peripheral nerve injury. 展开更多
关键词 anti-inflammatory reaction macrophage polarization NEUROINFLAMMATION peripheral nerve injury porcine decellularized nerve matrix hydrogel
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LEAST-SQUARES SOLUTIONS OF X^TAX = B OVER POSITIVE SEMIDEFINITE MATRIXES A 被引量:6
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作者 DongxiuXie LeiZhang 《Journal of Computational Mathematics》 SCIE CSCD 2003年第2期167-174,共8页
This paper is mainly concerned with solving the following two problems: Problem Ⅰ. Given X ∈ Rn×m, B . Rm×m. Find A ∈ Pn such thatwhereProblem Ⅱ. Given A ∈Rn×n. Find A ∈ SE such thatwhere F is Fro... This paper is mainly concerned with solving the following two problems: Problem Ⅰ. Given X ∈ Rn×m, B . Rm×m. Find A ∈ Pn such thatwhereProblem Ⅱ. Given A ∈Rn×n. Find A ∈ SE such thatwhere F is Frobenius norm, and SE denotes the solution set of Problem I.The general solution of Problem I has been given. It is proved that there exists a unique solution for Problem II. The expression of this solution for corresponding Problem II for some special case will be derived. 展开更多
关键词 positive semidefinite matrix Least-square problem Probenins norm
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OPTIMIZATION PROBLEMS IN EXTENSION MATRIXES 被引量:1
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作者 吴信东 《Science China Mathematics》 SCIE 1992年第3期363-373,共11页
In the extension matrix approach of inductive learning, the minimum formula (MFL) ofa positive example (e^+) against a set of negative examples (NE) and tbe optimal covering(MCV) of a set of positive examples (PE) aga... In the extension matrix approach of inductive learning, the minimum formula (MFL) ofa positive example (e^+) against a set of negative examples (NE) and tbe optimal covering(MCV) of a set of positive examples (PE) against NE are two striking optimization prob-lems. They have been proved to be NP-hard in Ref. [1]. This paper presents four algorithms,named MFL, HFL, MCV and HCV respectively. Algorithms MFL and MCV are complete forsolving the problems MFL and MCV but they opelate in exponential time on the number ofattributes in an example space and polynomial time on the number of examples. AlgorithmsHFL and HCV are two heuristic algorithms homologous to Algorithms MFL and MCV buttheir time complexities are polynomial. 展开更多
关键词 INDUCTIVE LEARNING EXTENSION MATRIX optimization NP-complexity POLYNOMIAL time.
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Construction of compressed sensing matrixes based on the singular pseudo-symplectic space over finite fields 被引量:1
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作者 Gao You Tong Fenghua Zhang Xiaojuan 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2016年第6期82-89,共8页
Compressed sensing(CS) provides a new approach to acquire data as a sampling technique and makes it sure that a sparse signal can be reconstructed from few measurements. The construction of compressed matrixes is a ... Compressed sensing(CS) provides a new approach to acquire data as a sampling technique and makes it sure that a sparse signal can be reconstructed from few measurements. The construction of compressed matrixes is a central problem in compressed sensing. This paper provides a construction of deterministic CS matrixes, which are also disjunct and inclusive matrixes, from singular pseudo-symplectic space over finite fields of characteristic 2. Our construction is superior to De Vore's construction under some conditions and can be used to reconstruct sparse signals through an efficient algorithm. 展开更多
关键词 compressed sensing matrix singular pseudo-symplectic space sparse signal disjunct matrix inclusive matrix
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RANK OF A CLASS OF AUTOCORRELATION MATRIXES IN SPECTRAL ESTIMATION
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作者 程乾生 《Chinese Science Bulletin》 SCIE EI CAS 1991年第1期72-74,共3页
Let x_l be a real stationary random signal with mean zero and autocorrelation
关键词 STATIONARY RANDOM signal RANK of AUTOCORRELATION MATRIX EXPONENTIAL model.
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基于Matrix Core的高性能多维FFT设计与优化 被引量:1
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作者 陆璐 祝松祥 +2 位作者 田卿燕 林海山 郭逸劼 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期20-30,共11页
快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利... 快速傅里叶变换(FFT)算法广泛应用于科学计算等领域。为了充分挖掘图形处理器(GPU)的计算能力并进一步提高FFT的计算效率,该文针对矩阵形式的Stockham FFT,提出了一种基于Matrix Core的高性能多维FFT计算方案。在计算优化方面,该方案利用Matrix Core加速FFT计算中的矩阵乘运算,同时通过编译器内部指令完成小粒度的矩阵乘加,使得Matrix Core支持更多尺寸的FFT计算。在内存优化方面,该方案使用2层迭代策略,以充分利用共享内存,减少与全局内存的数据交换;根据Matrix Core的矩阵数据在各个线程寄存器中的分布规律,直接在寄存器上完成FFT计算中大量存在的矩阵逐元素乘操作;通过对共享内存中的数据进行重排来缓解存储体冲突,并采用双缓冲策略缓解访存瓶颈。该文还提出了高效的矩阵转置策略,以加速多维FFT计算。在AMD MI250 GPU平台上将该方案与GPU上主流的高性能FFT计算库rocFFT和VkFFT进行了比较实验,结果表明:该方案在AMD MI250上的1维、2维和3维FFT平均计算效率均优于rocFFT和VkFFT,3维FFT的平均计算效率为rocFFT的1.5倍,为VkFFT的2.0倍,具有较好的性能提升;mcFFT的计算精度与rocFFT和VkFFT保持在相同水平。 展开更多
关键词 图形处理器 Matrix Core 快速傅里叶变换 矩阵乘法
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