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Enhancing the Trustworthiness of 6G Based on Trusted Multi-Cloud Infrastructure:A Practice of Cryptography Approach
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作者 Mingxing Zhou Peng Xiao +3 位作者 Qixu Wang Shuhua Ruan Xingshu Chen Menglong Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期957-979,共23页
Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integra... Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integrated network scenario.However,the openness and heterogeneity of the 6G network cause the problems of network security.To improve the trustworthiness of 6G networks,we propose a trusted computing-based approach for establishing trust relationships inmulti-cloud scenarios.The proposed method shows the relationship of trust based on dual-level verification.It separates the trustworthy states of multiple complex cloud units in 6G architecture into the state within and between cloud units.Firstly,SM3 algorithm establishes the chain of trust for the system’s trusted boot phase.Then,the remote attestation server(RAS)of distributed cloud units verifies the physical servers.Meanwhile,the physical servers use a ring approach to verify the cloud servers.Eventually,the centralized RAS takes one-time authentication to the critical evidence information of distributed cloud unit servers.Simultaneously,the centralized RAS also verifies the evidence of distributed RAS.We establish our proposed approach in a natural OpenStack-based cloud environment.The simulation results show that the proposed method achieves higher security with less than a 1%system performance loss. 展开更多
关键词 6G multi-cloud trusted Infrastructure remote attestation commercial cipher
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The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian Stage (Permian) 被引量:39
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作者 Yugan Jin Shuzhong Shen +5 位作者 Charles M. Henderson Xiangdong Wang Wei Wang Yue Wang Changqun Cao Qinghua Shang 《Episodes》 SCIE 2006年第4期253-262,共10页
关键词 二叠纪 历史地质 同位素 全球层型解剖面和点
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A win-win technique of stabilizing sand dune and purifying paper mill black-liquor 被引量:15
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作者 WANG Hanjie Penning de Vries FRITS JIN Yongcan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第4期488-493,共6页
The principle and technique were reported here to produce lignin-based sand stabilizing material (LSSM) using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sa... The principle and technique were reported here to produce lignin-based sand stabilizing material (LSSM) using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sand dunes were started in 2002. The field experiment was carded out in August 2005 when the newly formed plant community was 3 years old. The results from the comprehensive field experiment demonstrated that unlike polyvinyl acetate or foamed asphalt commonly used for dune stabilization, LSSM was plant- friendly material and could be used in combination with seeding and planting of desert species. With the help of LSSM, the desert species (i.e., Agriophyllum squarrosum (L.) Moq. and Artemisia desertorum Spreng. etc.) could be used to form community in 2-3 yeas and to stabilize sand dune effectively. The newly formed community was sustainable under an extremely dry climate condition. The organic matter and total nitrogen in the soil increased significantly as the community were formed, while the change in P and K contents in the soil was negligible. 展开更多
关键词 climate change desertification control straw pulping black liquor purification
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Boundedness of Caldero'n-Zygmund operators in product Hardy spaces 被引量:2
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作者 HAN Yong-sheng YANG Da-chun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第3期321-335,共15页
By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé i... By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé is established. 展开更多
关键词 Hardy space product domain Calderón-Zygmund operator vector-valued operator
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On the adjacent vertex-distinguishing acyclic edge coloring of some graphs 被引量:3
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作者 SHIU Wai Chee CHAN Wai Hong +1 位作者 ZHANG Zhong-fu BIAN Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第4期439-452,共14页
A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of ... A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of edges incident with v, where uv∈ E(G). The adjacent vertex distinguishing acyclic edge chromatic number of G, denoted by X'Aa(G), is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G. If a graph G has an adjacent vertex distinguishing acyclic edge coloring, then G is called adjacent vertex distinguishing acyclic. In this paper, we obtain adjacent vertex-distinguishing acyclic edge coloring of some graphs and put forward some conjectures. 展开更多
关键词 Adjacent strong edge coloring adjacent vertex-distinguishing acyclic edge coloring.
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Single-layer graphene as a highly selective barrier for vanadium crossover with high proton selectivity 被引量:1
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作者 Saheed Bukola Zhaodong Li +5 位作者 Jason Zack Christopher Antunes Carol Korzeniewski Glenn Teeter Jeffrey Blackburn Bryan Pivovar 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期419-430,I0009,共13页
We report near-zero crossover for vanadium cross-permeation through single-layer graphene immobilized at the interface of two Nafion?polymer electrolyte membranes.Vanadium ion diffusion and migration,including proton ... We report near-zero crossover for vanadium cross-permeation through single-layer graphene immobilized at the interface of two Nafion?polymer electrolyte membranes.Vanadium ion diffusion and migration,including proton mobility through membrane composites,were studied with and without graphene under diffusion and migration conditions.Single-layer graphene was found to effectively inhibit vanadium ion diffusion and migration under specific conditions.The single-layer graphene composites also enabled remarkable ion transmission selectivity improvements over pure Nafion membranes,with proton transport being four orders of magnitude faster than vanadium ion transport.Resistivity values of 0.02±0.005Ωcm^(2) for proton and 223±4Ωcm^(2) for vanadium ion through single atomic layer graphene are reported.This high selectivity may have significant impact on flow battery applications or for other electrochemical devices where proton conductivity is required,and transport of other species is detrimental.Our results emphasize that crossover may be essentially completely eliminated in some cases,enabling for greatly improved operational viability. 展开更多
关键词 Ion selectivity Polymer electrolyte membrane Redox flow battery Single-layer graphene Vanadium crossover 2D nanomaterial
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An FEM approximation for a fourth-order variational inequality of second kind 被引量:1
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作者 QIAN Fu-bin DING Rui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期19-24,共6页
A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered. By using regularization method, the original problem can be formulated as a differentiable variatio... A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered. By using regularization method, the original problem can be formulated as a differentiable variational equation, and the corresponding discrete FEM variational equation is presented afterwards. Abstract error estimates and error estimates of the approximation are derived in terms of energy norm and L^2-norm. 展开更多
关键词 plate theory variational inequality of the second kind fourth-order problem FEM regularization error estimate.
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Electroencephalography Analysis Using Neural Network and Support Vector Machine during Sleep 被引量:3
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作者 JeeEun Lee Sun K. Yoo 《Engineering(科研)》 2013年第5期88-92,共5页
The purpose of this paper is to analyze sleep stages accurately using fast and simple classifiers based on the frequency domain of electroencephalography(EEG) signal. To compare and evaluate system performance, the ru... The purpose of this paper is to analyze sleep stages accurately using fast and simple classifiers based on the frequency domain of electroencephalography(EEG) signal. To compare and evaluate system performance, the rules of Rechtschaffen and Kales(R&K rule) were used. Parameters were extracted from preprocessing process of EEG signal as feature vectors of each sleep stage analysis system through representatives of back propagation algorithm and support vector machine (SVM). As a result, SVM showed better performance as pattern recognition system for classification of sleep stages. It was found that easier analysis of sleep stage was possible using such simple system. Since accurate estimation of sleep state is possible through combination of algorithms, we could see the potential for the classifier to be used for sleep analysis system. 展开更多
关键词 SLEEP ELECTROENCEPHALOGRAPHY NEURAL Network Backpropagation Algorithm SVM
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EFFECTS OF PROCESSING OPERATIONS ON ZETA POTENTIAL AND CATIONIC DEMAND OF PULPS 被引量:1
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作者 Nishi K. Bhardwaj Sanjay Kumar Pramod K. Bajpai 《天津科技大学学报》 CAS 2004年第A01期276-280,共5页
The zeta potential and cationic demands of various kraft pulps - unbleached, bleached and beaten to different freeness levels were determined in the laboratory. The zeta potential of pulp where the final stage was a l... The zeta potential and cationic demands of various kraft pulps - unbleached, bleached and beaten to different freeness levels were determined in the laboratory. The zeta potential of pulp where the final stage was a lignin degrading and dissolving treatment such as alkaline extraction or hypochlorite was lower than the unbleached pulp. The cationic demand of unbleached pulp was higher compared to that of bleached pulp. Beaten pulps showed larger cationic demands than the unbeaten pulps, which can be attributed to the larger specific surface area of pulp components. Fibres become increasingly electronegative when beaten and therefore cationic demand of pulps increases with beating. When the zeta potential method is used with furnishes of different freeness, the linear relationship is observed. However, the slope is decreasing with the decrease in freeness of the pulp. 展开更多
关键词 牛皮纸浆 Z电势 阳离子需求 漂白纸浆 电动学
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Jichengite 3CuIr_2S_4·(Ni,Fe)_9S_8,a New Mineral,and Its Crystal Structure 被引量:1
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作者 Zuxiang Yü Ziguo HAO +2 位作者 Hanggen WANG Shuping YIN Jianhui CAI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第5期1022-1027,共6页
A new mineral,jichengite ideally 3CuIr_2S_4·(Ni,Fe)_9S_8,was found as a constituent of placer concentrates at a branch of the Luanhe River,about 220 km NNE of Beijing.Its associated minerals are chromite,magnetit... A new mineral,jichengite ideally 3CuIr_2S_4·(Ni,Fe)_9S_8,was found as a constituent of placer concentrates at a branch of the Luanhe River,about 220 km NNE of Beijing.Its associated minerals are chromite,magnetite,ilmenite,zircon,native gold,iridium,ferrian platinum and osmium.The placer is distributed at places around ultrabasic rock,which hosts chromite orebodies,from which PGM originated.Jichengite occurs commonly as massive or granular aggregates.No perfect morphology of jichengite was observed.It is steel gray and opaque with metallic luster and black streak.It has a Mohs hardness of 5,VHN(d) urn 21.65,H_m 4.465,Hv = 268.1 N/um^2.It is brittle and weakly magnetic. Cleavage {010} is rarely observed.No fracture was observed.Density could not be measured because of its too small grain size.Density(calc.) is 7.003 g/cm^3.Reflect light is reddish-brown,without internal reflections.Anisotropism is distinct with grayish or yellowish white in crossed nicols and bluish violetcopper red in uncrossed nicols.Jichengite shows weak pleochroism and strong bireflectance.The reflectance values in air at the Standard Commission on Ore Mineralogy wavelengths are:38.9,34.3 at 470 nm,38.9,34.5 at 546 nm,39.1,35.3 at 590 nm,39.2,36.8 at 650 nm,parallel-axial extinction.The six strongest lines in the X-ray powder-diffraction pattern[d in A,(I),(hkl)]are:3.00(100)(116),2.80(50) (205),2.48.(50)(208),1.916(40)(2,1,10),1.765(60)(220),1.753(50)(2,0,16).Five chemical analyses carried out,yielding the following results:S 25.76(25.49-5.97),Fe 10.03(9.78-10.31),Co 0.78 (0.75-0.81),Ni 12.48(12.32-12.85),Cu 4.77(4.69-4.83),Ir 46.98(46.14-47.89),sum 100.80wt%,which produced a formula(Cu_(1.556)Fe_(0.976))_(2.532)(Ir_(5.063)S_(10.126))·(Fe_(2.7451)Ni_(4.404)Co_(0.273))_(7.422)S_(6.517).The ideal formula is X_(10)Ir_5S_(17.5),which was calculated by single crystal structure analyses,where X=Cu(Ⅱ)+Fe(Ⅱ)+Ni(Ⅱ) +Co(Ⅱ).The single crystal data were collected using a diffractometer with Mo Kαradiation and a graphite monochromate.The crystal system is trigonal with space group R3m and unit cell parameters a=7.0745(14) A,c=34.267(10) A(The superstructure not found),and the final R Indices[with 564 observed reflections,I>2sigma(Ⅰ)]are R_1=0.0495,wR_2=0.1349.The specimens are deposited in the Geological Museum of China. 展开更多
关键词 jichengite crystal structure MINERAL
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Soil fertility effect on water productivity of maize in the upper blue nile basin, Ethiopia 被引量:1
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作者 Teklu Erkossa Seleshi Bekele Awulachew Denekew Aster 《Agricultural Sciences》 2011年第3期238-247,共10页
Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by po... Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by poor soil, water and crop management practices. This study simulated the water productivity of the crop under varying soil fertility scenarios (poor, near optimal and none limiting) using hybrid seeds under rainfed conditions using the FAO AquaCrop model. The result indicated that grain yield of maize increased from 2.5 tons.ha–1 under poor to 6.4 and 9.2 tons.ha–1 with near optimal and non-limiting soil fertility conditions. Correspondingly, soil evaporation decreased from 446 mm to 285 and 204 mm, while transpiration increased from 146 to 268 and 355 mm. Consequently, grain water productivity was increased by 48% and 54%, respectively, with the near optimal and non-limiting soil fertility conditions. The water productivity gain mainly comes from reduced evaporation and increased transpiration without significantly affecting water left for downstream ecosystem services. This has a huge implication for a basin scale water management planning for various purposes. 展开更多
关键词 AquaCrop Simulation Water PRODUCTIVITY Soil FERTILITY Nitisols
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Fungicide tolerance of <i>Trichoderma asperelloides</i>and <i>T. harzianum strains</i> 被引量:1
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作者 Adriana Paola Chaparro Lilliana Hoyos Carvajal Sergio Orduz 《Agricultural Sciences》 2011年第3期301-307,共7页
Tolerance in isolations of Trichoderma was developed by exposing two strains of T. harzianum and three of T. asperelloides to increasing concentrations of chemical fungicides. These isolation of Trichoderma were expos... Tolerance in isolations of Trichoderma was developed by exposing two strains of T. harzianum and three of T. asperelloides to increasing concentrations of chemical fungicides. These isolation of Trichoderma were exposed to three fungicides: Captan, Thiabendazol and the mixture Captan-Carboxin. Some selected lines of these strains reached tolerance to Captan and partial tolerance to the mixture Captan-Carboxin. The biological and genetic changes in these tolerant lines were monitored by determining the relative growth rate of the fungus, inhibition of Fusarium and by analyzing the genomic changes through UP-PCR. The results show that the tolerance to fungicides can be developed without affecting the parameters of biological activity in these lines of Trichoderma (growth and parasitism against Fusarium). Chemical tolerance to the fungicide was verified by means of changes at the DNA level (UP-PCR), mainly in the lines tolerant to Captan. This suggests that Trichoderma survives in environments with remnants of fungicide molecules. 展开更多
关键词 TRICHODERMA Mutation Chemical FUNGICIDE Biological Control Tolerance
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Report on a breeding objective that may reduce the carbon footprint of extensive cow-calf production systems 被引量:1
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作者 Motshabi Catherine Mokolobate Machiel Matthys Scholtz +1 位作者 Sendros Demeke Mulugeta Frederick Wilhelm Cornelius Neser 《Natural Science》 2013年第1期167-171,共5页
Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned pe... Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned per Large Stock Unit (LSU) can eventually be translated to kilogram calf produced per kg CO2 equivalent. A LSU is defined as a bovine requiring 75 MJ Metabolisable Energy (ME) per day. If more kilogram weaner calf can be produced per LSU (KgC/LSU), the carbon footprint of beef can be reduced. This study used breed average values to investigate the KgC/LSU for the 30 beef and dual purpose breeds in South Africa. The breeds were categorized in the following breed types: Sanga (indigenous to South Africa) Sanga derived, Zebu, Zebu derived, British and European. No relationship was found between cow weights and KgC/LSU, indicating that it is independent of cow weight between breeds. However, when the data is summarized into breed types, the Sanga and European breed types produce the least KgC/ LSU and Sanga derived breed types the most. This high value of the Sanga derived breeds is probably due to retained heterosis. Composite breeds are mostly intermediate to parental breeds for individual traits but superior for composite traits and KgC/LSU is a composite trait. These calculations were only done on breed averages. A genetic analysis on a breed level to estimate genetic parameters for this trait, and its genetic correlations with other traits now needs to be done before a decision can be taken whether selection for KgC/LSU will be feasible. The ultimate aim with a trait like this is to reduce the carbon footprint of weaner calf production since more kilogram calf will be produced per LSU (constant feed unit). 展开更多
关键词 BEEF Production Breeding CATTLE Large STOCK Unit Sanga Weaner CALF Component
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Dynamic Response and Oscillating Behaviour of Fractionally Damped Beam
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作者 Diptiranjan Behera S.Chakraverty 《Computer Modeling in Engineering & Sciences》 SCIE EI 2015年第3期211-225,共15页
This paper presents the numerical solution of a viscoelastic continuous beam whose damping behaviours are defined in term of fractional derivatives of arbitrary order.Homotopy Perturbation Method(HPM)is used to obtain... This paper presents the numerical solution of a viscoelastic continuous beam whose damping behaviours are defined in term of fractional derivatives of arbitrary order.Homotopy Perturbation Method(HPM)is used to obtain the dynamic response with respect to unit impulse load.Obtained results are depicted in term of plots.Comparisons are made with the analytic solutions obtained by Zu-feng and Xiao-yan(2007)to show the effectiveness and validation of the present method. 展开更多
关键词 VISCOELASTIC BEAM Fractional derivative IMPULSE response function HOMOTOPY Perturbation Method(HPM)
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Influence of Functionalization on the Structural and Mechanical Properties of Graphene
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作者 L.S.Melro L.R.Jensen 《Computers, Materials & Continua》 SCIE EI 2017年第2期109-127,共19页
Molecular dynamics simulations were applied in order to calculate the Young’s modulus of graphene functionalized with carboxyl,hydroxyl,carbonyl,hydrogen,methyl,and ethyl groups.The influence of the grafting density ... Molecular dynamics simulations were applied in order to calculate the Young’s modulus of graphene functionalized with carboxyl,hydroxyl,carbonyl,hydrogen,methyl,and ethyl groups.The influence of the grafting density with percentages of 3,5,7,and 10%and the type of distribution as a single cluster or several small clusters were also studied.The results show that the elastic modulus is dependent on the type of functional groups.The increasing coverage density also evidenced a decrease of the Young’s modulus,and the organization of functional groups as single cluster showed a lesser impact than for several small clusters.Furthermore,the bond length and angle distribution probability analyses reveal that lengths and angles are affected with increasing functionalization suggesting more out-of-plane displacements of the carbon atoms within the graphene structure. 展开更多
关键词 FUNCTIONALIZATION GRAPHENE molecular dynamics Young’s modulus structural properties
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A MPI PARALLEL PRECONDITIONED SPECTRAL ELEMENT METHOD FOR THE HELMHOLTZ EQUATION
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作者 洪桃李 许传炬 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第1期56-66,共11页
Spectral element method is well known as high-order method, and has potential better parallel feature as compared with low order methods. In this paper, a parallel preconditioned conjugate gradient iterative method is... Spectral element method is well known as high-order method, and has potential better parallel feature as compared with low order methods. In this paper, a parallel preconditioned conjugate gradient iterative method is proposed to solving the spectral element approximation of the Helmholtz equation. The parallel algorithm is shown to have good performance as compared to non parallel cases, especially when the stiffness matrix is not memorized. A series of numerical experiments in one dimensional case is carried out to demonstrate the efficiency of the proposed method. 展开更多
关键词 光谱元素法 平行计算法 有限元法 矩阵 计算方法
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Macrophage Inflammatory Protein-lalpha mediates Matrix Metalloproteinase-9 enhancement in human adherent monocytes fed with malarial pigment
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作者 Giuliana Giribaldi Elena Valente +2 位作者 Amina Khadjavi Manuela Polimeni Mauro Prato 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第12期925-930,共6页
Objective:To investigate the role of macrophage inflammatory protein-1alpha(MIP-1 alpha) in the detrimental enhancement of matrix mnetalloproteinase-9(MMP-9) expression,release and activity induced by phagocytosis of ... Objective:To investigate the role of macrophage inflammatory protein-1alpha(MIP-1 alpha) in the detrimental enhancement of matrix mnetalloproteinase-9(MMP-9) expression,release and activity induced by phagocytosis of malarial pigment(haemozoin,HZ) in human monocytes. Methods:Human adherent monocytes were unfed/fed with native HZ for 2 h.After 24 hours. MIP-1 alpha production was evaluated by ELISA in cell supernatants.Alternatively.HZunfed /fed monocytes were treated in presence/absence of anti-human MIP-1 alpha blocking antibodies or recombinant human MIP-lalpha for 15 h(RNA studies) or 24 h(protein studies): therefore,MMP-9 mRNA expression was evaluated in cell lysatcs by Real Time RT-PCR,whereas proMMP-9 and active MMP-9 protein release were measured in cell supernatants by Western blotting and gelatin zvmography.Results:Phagocytosis of HZ by human monocytes increased production of MIP-1 alpha.mRNA expression of MMP-9 and protein release of proMMP-9 and active MMP-9.All the HZ-enbancing effects on MMP-9 were abrogated by anti-human MIP- 1 alpha blocking antibodies and mimicked by recombinant human MIP-l alpha.Conclusions: The present work suggests a role for MIP-lalpha in the HZ-dependent enhancement of MMP-9 expression,release and activity observed in human monocytes.higbligbtiug new detrimental effects of HZ-triggered proinflammatory response by phagocytic cells in falciparum malaria. 展开更多
关键词 PLASMODIUM FALCIPARUM Malaria MONOCYTE PHAGOCYTOSIS Haemozoin Matrix metalloproteinase-9 Macrophage inflammatory proteinlalpha
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Liposome as vaccine adjuvant and delivery system
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作者 GUO Xiu-Xia YANG Qian +1 位作者 YU Hong-Tao SHENG Jun 《中国免疫学杂志》 CAS CSCD 北大核心 2006年第6期585-591,共7页
关键词 CPGODN Liposome as vaccine adjuvant and delivery system ORAL CTLS
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WET STRENGTH PAPER REPULPING: LABORATORY EVALUATION
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作者 Nishi K. Bhardwaj Vikas Rajan A. G. Kulkarni 《天津科技大学学报》 CAS 2004年第A02期226-232,共7页
The recycling of wet strength papers in a normal recycling mill is often troublesome due to the severe operating conditions required to defibre wet strength papers. The various methods are presented which will quickly... The recycling of wet strength papers in a normal recycling mill is often troublesome due to the severe operating conditions required to defibre wet strength papers. The various methods are presented which will quickly allow mills to determine the most effective pulping aids to use when repulping wet strength papers. The repulping of wet strength paper with inorganic chemicals was investigated in the laboratory. The effects of major variables, that is, repulping time, pulp consistency, soaking time, temperature, and reactant concentration in the repulping stage were examined using Plackett-Burman design. The repulping time was the most crucial & influential process variable affecting repulping characteristic and formation related properties. The more significant repulping process variables affecting pulp yield were repulping time, soaking temperature and pulp consistency whereas for formation index and feature size, repulping time, pulp consistency, soaking temperature and time were the more important variables. The formation index is increased by an increase in repulping time, pulp consistency and soaking time whereas the feature size is decreased by an increase in repulping time, soaking temperature and pulp consistency. The formation index and the rejects were more sensitive to changes in process variables than were the feature size or the pulp yield. The pulp recycled from wet strength waste paper had good physical strength properties. 展开更多
关键词 实验室评估 再制浆 湿润强度纸 无机化学 浸水时间 废纸 回收利用
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Improving Effect of Salicylic Acid on the Multipurpose Tree <i>Ziziphus spina-christi</i>(L.) Willd Tissue Culture
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作者 Abdelnasser Galal 《American Journal of Plant Sciences》 2012年第7期947-952,共6页
Salicylic acid (SA) is one of numerous phenolic compounds found in plants with numerous important physiological events. Exogenously application of Salicylic acid (SA) is useful for the growth and development of plants... Salicylic acid (SA) is one of numerous phenolic compounds found in plants with numerous important physiological events. Exogenously application of Salicylic acid (SA) is useful for the growth and development of plants. This investigation aimed to study the improving effect of salicylic acid on the tissue culture of Ziziphus spina-christi. To study its improving effect were used shoot-tip explants cultured on Murashige and Skoog (MS) solid medium supplemented with different concentrations and various combinations of auxins, cytokinins and Salicylic acid. Media without growth regulators enhanced the growth and elongation of shoot-tip explants not its proliferation. Lower concentrations of cytokinin were better for shoot-tip proliferation than higher ones. 6-Benzylaminopurine (BAP) was superior to kinetin (KN) in shoot-tip proliferation. The optimum culture conditions for shoot-tip proliferation were achieved on MS medium supplemented with 0.25 mg/l 6-Benzylaminopurine (BAP) and 25 mg/l Salicylic acid (SA). The optimum culture conditions for callus formation were obtained on MS medium supplemented with 3 mg/l 2,4-Dichlorophenoxyacetic acid (2,4-D) and 25 mg/l Salicylic acid (SA), while the optimum culture conditions for somatic callus formation were obtained on MS medium supplemented with 2.0 mg/l 2,4-Dichlorophenoxyacetic acid (2,4-D) and 10 mg/l Salicylic acid (SA). The optimum culture conditions for rooting of shoots were obtained on MS medium supplemented with 0.25 mg/l of Indole-3-butyric acid (IBA) and 10 mg/l Salicylic acid (SA). The highest percentage of survival plants was obtained in the soil mixture supplied with 10 mg/l Salicylic acid (SA). Salicylic acid (SA) showed positive effect and good response on callusing, shooting and rooting of Z. spina-christi. Cultures received small amounts of salicylic acid were better than those lack it. 展开更多
关键词 Callus Growth Regulator Multiplication Shoot-Tips Somatic Embryogenesis ZIZIPHUS spina-christi
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