As a result of the fierceness of business competition, companies, to remaincompetitive, have to charm their customers by anticipating their needs and being able to rapidlydevelop exciting new products for them. To ove...As a result of the fierceness of business competition, companies, to remaincompetitive, have to charm their customers by anticipating their needs and being able to rapidlydevelop exciting new products for them. To overcome this challenge, technology forecasting isconsidered as a powerful tool in today's business environment, while there are as many successstories as there are failures, a good application of this method will give a good result. Amethodology of integration of patterns or lines of technology evolution in TRIZ parlance ispresented, which is also known as TRIZ technology forecasting, as input to the QFD process to designa new product. For this purpose, TRIZ technology forecasting, one of the TRIZ major tools, isdiscussed and some benefits compared to the traditional forecasting techniques are highlighted. Thena methodology to integrate TRIZ technology forecasting and QFD process is highlighted.展开更多
This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sedim...This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sediments are characteristic of glacigenic deposits, but very different from those of aeolian and lacustrine sediments. Moreover, the grain size distributions of the proglacial sediments are fractal with a dimension of about 2.9, and the fractal dimensions can be used as another summary statistical parameter for quantifying the relative amounts of coarse and fine materials. Correlations between the absolute element abundances of the proglacial sediments are very weak due to mineral partitioning and other effects of glacial processes, but correlations between the element/Rb ratios are statistically significant. This finding indicates that element/Rb ratios can be used to reduce or eliminate the effects of glacial processes, evaluate geochemical data and determine the sediment provenance in the foreland of Antarctic glacier. Comparisons on the element concentrations among different environments suggest that the proglacial sediments are derived predominantly from local bedrocks and appear to be natural in origin. Thus these natural sediments can be used to study chemical weathering in the proglacial foreland of modern glacier.展开更多
An adaptive immune algorithm (AIA) was proposed for resolution of the overlapping GC/MS signal with background.By using AIA, the chromatographic profiles corresponding to the independent components (ICs) in the overla...An adaptive immune algorithm (AIA) was proposed for resolution of the overlapping GC/MS signal with background.By using AIA, the chromatographic profiles corresponding to the independent components (ICs) in the overlapping signal are calculated with the mass spectra extracted by means of independent component analysis (ICA). The number of the ICs in the overlapping signal is determined by the difference between the reconstructed and the original data. Both simulated and experimental data are investigated with the proposed AIA approach. It was found that the mass spectra and chromatographic profiles of the components in an overlapping multicomponent GC/MS signal can be accurately resolved with the existence of background, and the results are better than that by using an interactive self-modeling mixture analysis (SIMPLISMA) method. The AIA approach may be a promising tool for the resolution of overlapping GC/MS signal.展开更多
We first derive a Darboux transformation for a (2+ 1)-extension of Burgers equation. Then we consider theLie symmetries, symmetry algebra, and symmetry reductions of the equation, and use symmetry reductions to obtain...We first derive a Darboux transformation for a (2+ 1)-extension of Burgers equation. Then we consider theLie symmetries, symmetry algebra, and symmetry reductions of the equation, and use symmetry reductions to obtaingroup-invariant solutions to the equation.展开更多
Soil labile (biologically active) organic carbon fractions under different crop rotation systems in Jiangsu Province, China, were investigated after 10 years of rotation. The rotation systems, including green manureri...Soil labile (biologically active) organic carbon fractions under different crop rotation systems in Jiangsu Province, China, were investigated after 10 years of rotation. The rotation systems, including green manurerice-rice (GmRR), wheat-rice-rice (WRR), wheat-rice (WR) and wheat/corn intercrop-rice (WCR) rotations,were established on paddy soils using a randomized complete block design with three replicates. The total organic carbon (TOC), total nitrogen (TN) and water-soluble organic carbon (WSOC) in the soils under different systems were greater in the GmRR and WRR than in the WR and WCR rotation systems because the soils under triple cropping often received more crop residues than the soils under double cropping. Both the WSOC and the microbial biomass carbon (MBC) contents in the soils of the GmRR rotation system were significantly greater than those in the other crop rotation systems, which was due to the return of green manure to the fields of the GmRR rotation system. The results of a 13C nuclear magnetic resonance (13C-NMR) analysis indicated that the structural characteristics of soil WSOC were similar under the four crop rotation systems with carbohydrates and long-chain aliphatics being the major components. Correlation analysis showed that the content of the WSOC was positively correlated with that of the MBC (P <0.01),and all had significantly positive correlations with TOC and TN. The coefficients of variation (CVs) for WSOC and WSOC/TOC were greater than the other indices (e.g, MBC, TOC and TN), suggesting that WSOC in the soils was more sensitive to these rotation systems. The results above indicated that the soil amended with green manure could not only increase the usable C source for soil microorganisms, but could also enhance soil organic matter content; hence, rotation with green manure would be a good strategy for sustainable agriculture.展开更多
A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wave...A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wavelength. The crystal structure of anatase was characterized by XRD. The structure analysis result of X-ray fluorescence(XRF) shows that doped-nitrogen was presented in the sample. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants. The photocatalytic activities of samples were increasing gradually with calcination temperature from 400℃ to 700℃ under UV irradiation. It can be seen that the degradation of methyl orange follows zero-order kinetics. However, the calcination temperatures have no significant influence on the degradation of phenol under sunlight. The N-doped catalyst shows higher activity than the bare one under solar irradiation.展开更多
During mitosis, the parent cell distributes its genetic materials equally into two daughter cells through chromosome segregation, a complex movements orchestrated by mitotic kinases and its effector proteins. Faithful...During mitosis, the parent cell distributes its genetic materials equally into two daughter cells through chromosome segregation, a complex movements orchestrated by mitotic kinases and its effector proteins. Faithful chromosome segregation and cytokinesis ensure that each daughter cell receives a full copy of genetic materials of parent cell. Defects in these processes can lead to aneuploidy or polyploidy. Aurora/Ipl1p family, a class of conserved serine/threonine kinases, plays key roles in chromosome segregation and cytokinesis. This article highlights the function and regulation of Aurora/Ipllp family in mitosis and provides potential links between aberrant regulation of Aurora/Ipllp kinases and pathogenesis of human cancer.展开更多
We propose two kinds of new Jaynes Cummings models relating to two-photon process by using the supersymmetric unitary transformation. The corresponding energy eigenvalues and eigenvectors are obtained.
We propose two schemes for teleporting an unknown state.In our schemes,a three-particle Greenberger-Hornezeilinger state is used as a quantum channel.We show that the probabilistic teleportation of an unknown quantum ...We propose two schemes for teleporting an unknown state.In our schemes,a three-particle Greenberger-Hornezeilinger state is used as a quantum channel.We show that the probabilistic teleportation of an unknown quantum atate can be realized.展开更多
AIM: To choose an appropriate methods for the isolation of hepatic lymphocytes between the mechanical dissection and the enzymatic digestion and investigate the effects of two methods on phenotype and function of hepa...AIM: To choose an appropriate methods for the isolation of hepatic lymphocytes between the mechanical dissection and the enzymatic digestion and investigate the effects of two methods on phenotype and function of hepaticlymphocytes.METHODS: Hepatic lymphocytes were isolated from untreated, poly (I:C)-stimulated or ConA-stimulated mice using the two methods, respectively. The cell yield per liver was evaluated by direct counting under microscope.Effects of digestive enzymes on the surface markers involved in hepatic lymphocytes were represented by relative change rate [(percentage of post-digestionpercentage of pre-digestion)/percentage of pre-digestion].Phenotypic analyses of the subpopulations of hepatic lymphocytes and intracellular cytokines were detected by flow cytometry. The cytotoxicity of NK cells from wild C57BL/6 or poly (I:C)-stimulated C57BL/6 mice was analyzed with a 4-h ^51Cr release assay.RESULTS: NK1.1^+ cell markers, NK1.1 and DX5, were significantly down-expressed after enzymatic digestion and their relative change rates were about 28% and 32%,respectively. Compared with the enzymatic digestion, the cell yield isolated from unstimulated, poly (I:C)-treated or ConA-treated mice by mechanical dissection was not significantly decreased. Hepatic lymphocytes isolated by the mechanical dissection comprised more innate immune cells like NK, NKT and γδ cells in normal C57BL/6 mice.After poly (I:C) stimulation, hepatic NK cells rose to about 35%, while NKT cells simultaneously decreased. Following ConA injection, the number of hepatic NKT cells was remarkably reduced to 3.67%. Higher ratio of intracellular IFN-γ^+(68%) or TNF-α^+(15%) NK1.1^+ cells from poly (I:C)treated mice was obtained using mechanical dissection method than control mice. There was no difference in viability between the mechanical dissection and the enzymatic digestion, and hepatic lymphocytes obtained with the two methods had similar cytotoxicity against YAC-1 cells.CONCLUSION: There is no difference in the cell yield and viability of the hepatic lymphocyte isolated with the two methods. The mechanical dissection, but not the enzymatic digestion, may be suitable for the phenotypic analysis of hepatic NK1.1^+ cell.展开更多
Hydrogen isotopic compositions of pyroxenes in peridotite xenoliths from the Nushan volcano, Anhui Province, SE China have been obtained using an ion probe (Cameca 1270). D/H ratios are constant within a single grain ...Hydrogen isotopic compositions of pyroxenes in peridotite xenoliths from the Nushan volcano, Anhui Province, SE China have been obtained using an ion probe (Cameca 1270). D/H ratios are constant within a single grain and among the different grains from the same sample. The lack of correlation between the D/H ratios and the hydrogen contents indicates that the hydrogen isotopic compositions are inherited from their mantle source. Combining with the δD values of coexisting amphiboles, it is inferred that the Nushan mantle experienced at least a two-stage metasomatic event. One was responsible for formation of amphiboles with extremely variable δD values, and the other was probably responsible for the high δD values (up to ?20‰) of some clinopyroxenes from peridotites, clinopyroxene and mica megacrysts. High δD values point to a subduction-related fluid being involved in one metasomatic event. The primary δD values (?90‰ to ?140‰) of the Nushan pyroxenes, together with data gleaned from the literature, suggest that the D/H ratios of the nominally anhydrous mineral reservoir might have differed from that of the other mantle hydrogen in being relatively depleted in D.展开更多
The Portevin-Le Chatelier (PLC) effect means serrated yielding or jerky flow phenomenon in some alloys. In this paper a macroscopic model is developed to investigate the PLC effect with the emphasis on mechanical resp...The Portevin-Le Chatelier (PLC) effect means serrated yielding or jerky flow phenomenon in some alloys. In this paper a macroscopic model is developed to investigate the PLC effect with the emphasis on mechanical response of the structure evolution on microscopic scale. In addition to the normal work hardening effect, the model takes account of the thermal activation of dislocation moving with the aid of stress and the collective interactions between mobile dislocations and solute atoms due to dynamic strain ageing (DSA). It can satisfy the negative strain rate sensitivity of flow stress, which is believed to be one of the most special features associated with the PLC effect. The heterogeneous nature of the deformed material is also considered by introducing a nonuniform spatial distribution of some model parameters. The serrated yielding and localized deformation behavior can be successfully reproduced via numerical simulation based on this model.展开更多
Based on the theory of Markov performance potentials and neuro-dynamic programming(NDP) methodology, we study simulation optimization algorithm for a class of continuous timeMarkov decision processes (CTMDPs) under ra...Based on the theory of Markov performance potentials and neuro-dynamic programming(NDP) methodology, we study simulation optimization algorithm for a class of continuous timeMarkov decision processes (CTMDPs) under randomized stationary policies. The proposed algo-rithm will estimate the gradient of average cost performance measure with respect to policy param-eters by transforming a continuous time Markov process into a uniform Markov chain and simula-ting a single sample path of the chain. The goal is to look for a suboptimal randomized stationarypolicy. The algorithm derived here can meet the needs of performance optimization of many diffi-cult systems with large-scale state space. Finally, a numerical example for a controlled Markovprocess is provided.展开更多
We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the op...We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the operator from H^1 to H^1 is compact if and only if it is weakly compact. Meanwhile, we get the analogue on the Bergman spaces.展开更多
Photoacoustic (PA) spectra of powdered neodymium oxide (Nd 2O 3 (A type)), neodymium hydrated chloride (NdCl 3·6H 2O) and neodymium fluoride (NdF 3) were reported. PA band shifts as compared to their positio...Photoacoustic (PA) spectra of powdered neodymium oxide (Nd 2O 3 (A type)), neodymium hydrated chloride (NdCl 3·6H 2O) and neodymium fluoride (NdF 3) were reported. PA band shifts as compared to their positions in aqueous Nd 3+ are used to calculate the nephelauxetic parameters of the compounds. The variation of these parameters and correlation with the nature of metal ligand bonding were discussed. A novel method is introduced to determine the relative values of oscillator strengths and Judd Ofelt parameters of powdered samples using PA spectroscopy. It is found that a linear correlation exists between relative values of τ 2 and oscillator strengths of hypersensitive transitions of the title compounds. It is hopetul that the new method of PA technique may serve for the Judd Ofelt quantitative analysis of powdered rare earth compounds.展开更多
The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron sp...The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption spectroscopy.The catalytic property was strongly influenced by the Fe substitution.The relation between catalytic performance and the degree of Fe substitution was examined with regard to the structure and surface characteristics of the mixed oxides.The Fe-containing catalysts exhibited higher activity attributable to the possible(Fe2+,Mo6+) and (Fe3+,Mo5+)valency pairs,and the highest activity was observed for Sr2Mg0.2Fe0.8MoO6-δ.The enhancement of the catalytic activity may be correlated with the Fe-relating surface lattice oxygen species and was discussed in view of the presence of oxygen vacancies.展开更多
For the first time, we apply different geospeedometric models to garnet zoning patterns that were obtained in this study from detailed EMP analyses for garnets from eclogites and granulite in the Dabie-Sulu orogen. Va...For the first time, we apply different geospeedometric models to garnet zoning patterns that were obtained in this study from detailed EMP analyses for garnets from eclogites and granulite in the Dabie-Sulu orogen. Various zonings of cation diffusion were preserved in the garnets, enabling the acquirement of average cooling rates for the high-to ultrahigh-pressure rocks without using geochronological approaches. The coesite-bearing hot eclogites yield fast cooling rates of about 20 to 30℃/Ma subsequent to peak metamorphic temperatures, whereas the cold eclogite gives a relatively slow cooling rate of 8℃/Ma at its initial exhumation. A very slow cooling rate of <0.3℃/Ma is obtained for the granulite at Huangtuling, suggesting that the granulite may not be involved in the continental deep subduction.展开更多
The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model. Taking the -dimensional Boussinesq equation as a simple example, six types o...The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model. Taking the -dimensional Boussinesq equation as a simple example, six types of conditional similarity reductions are obtained.展开更多
Radar remote sensing can acquire information of sub-surface covered by sand in arid area, detect surface roughness and vegetation coronet's layer and linear feature such as linear structure and channel sensitively...Radar remote sensing can acquire information of sub-surface covered by sand in arid area, detect surface roughness and vegetation coronet's layer and linear feature such as linear structure and channel sensitively. With sediment facies analysis, this paper studies the features of environmental evolution in mid-late Epipleistocene (60 ka BP-20 ka BP) in northeastern Ejin Banner. The conclusions are listed as follows: (1) The evolution of the three lakes, i.e. Gaxunnur, Sugunur and Tian'e lakes, are dominated by faults and regional climate. (2) By analyzing sedimentary section of old Juyanze Lake, the three lakes used to be a large outflow lake before 50 ka BP in northeastern Ejin Banner, and at 50 ka BP, temperature declined rapidly in northwestern China. The event caused the lake's shrinkage. (3) By fault activity uplift in the northern part of old Juyan Lake and depression in the southern part, the lake's water followed from north to south at around 35 ka BP, old Juyanze fluvial fan was formed. At the same time, Juyan Lake separated from Sugunur Lake and Wentugunr old channel was abandoned. (4) In recent 2000 years, Ruoshui River is a wandering river, sometimes it flows into Juyan Lake and sometimes Sugunur and Gaxunnur lakes. Due to human activities and over exploitation, the oasis ecosystem is rapidly degenerated in 15 years (1986-2000).展开更多
We have previously shown a critical role of prolactin (PRL) during maturation and anti-tumor effects of murine natural killer (NK) cells in vitro and in vivo. We extended that study by exploring the ability of human N...We have previously shown a critical role of prolactin (PRL) during maturation and anti-tumor effects of murine natural killer (NK) cells in vitro and in vivo. We extended that study by exploring the ability of human NK cell lines (NK-92 and YT cell) to express PRL receptor (PRL-R) and to respond to PRL stimulation in vitro. Both human NK cell lines constitutively expressed PRL-R on membrane and mRNA transcripts,NK-92 cells contained higher level of PRL-R than YT cells,which correlated to the enhanced capacity of the cells to proliferate and to lyse target cells in response to PRL stimulation in the presence of trace amount of IL-2 or IL-15 in vitro. Two differences between IL-2 and IL-15 in functioning on human NK cells were for the first time observed. PRL synergized with IL-15 to improve proliferation of NK cells in a dose-dependent manner without double peak manifesting like IL-2. Although PRL enhanced the cytotoxicity of IL-2 or IL- 15 activated NK cells,it exerted the function through up-regulating gene expression of perforin without influence of FasL in IL-2-stimulated NK cells,while in IL-15-stimulated NK cells,PRL did the function through up-regulating gene expression of both perforin and FasL but not IFNγ. PRL increased expressions of IL-2Rα on membrane and of IL-2 mRNA in cells,indicating that PRL up-regulated NK cell function by improving positive feedback between IL-2 and IL-2R. The similar results were also observed in network between IL-15 and IL-15R. These data indicate a potential role of PRL in human NK cell modulation.展开更多
基金This project is supported by National Natural Science Foundation of China(No.20172041) and Provincial Science Foundation of Anhui, China (No.03042308).
文摘As a result of the fierceness of business competition, companies, to remaincompetitive, have to charm their customers by anticipating their needs and being able to rapidlydevelop exciting new products for them. To overcome this challenge, technology forecasting isconsidered as a powerful tool in today's business environment, while there are as many successstories as there are failures, a good application of this method will give a good result. Amethodology of integration of patterns or lines of technology evolution in TRIZ parlance ispresented, which is also known as TRIZ technology forecasting, as input to the QFD process to designa new product. For this purpose, TRIZ technology forecasting, one of the TRIZ major tools, isdiscussed and some benefits compared to the traditional forecasting techniques are highlighted. Thena methodology to integrate TRIZ technology forecasting and QFD process is highlighted.
基金The work was supported by the Nationa1 Natural ScienceFoundation of China(Grant No.40231002 and 40076032)the project of Chinese Academy of Sciences(Grant No.KZCX2-303)
文摘This paper presents a detailed study on the textural and geochemical characteristics of the proglacial sediments near the edge of modern Nelson Ice Cap, Antarctica. The grain size distributions of the proglacial sediments are characteristic of glacigenic deposits, but very different from those of aeolian and lacustrine sediments. Moreover, the grain size distributions of the proglacial sediments are fractal with a dimension of about 2.9, and the fractal dimensions can be used as another summary statistical parameter for quantifying the relative amounts of coarse and fine materials. Correlations between the absolute element abundances of the proglacial sediments are very weak due to mineral partitioning and other effects of glacial processes, but correlations between the element/Rb ratios are statistically significant. This finding indicates that element/Rb ratios can be used to reduce or eliminate the effects of glacial processes, evaluate geochemical data and determine the sediment provenance in the foreland of Antarctic glacier. Comparisons on the element concentrations among different environments suggest that the proglacial sediments are derived predominantly from local bedrocks and appear to be natural in origin. Thus these natural sediments can be used to study chemical weathering in the proglacial foreland of modern glacier.
文摘An adaptive immune algorithm (AIA) was proposed for resolution of the overlapping GC/MS signal with background.By using AIA, the chromatographic profiles corresponding to the independent components (ICs) in the overlapping signal are calculated with the mass spectra extracted by means of independent component analysis (ICA). The number of the ICs in the overlapping signal is determined by the difference between the reconstructed and the original data. Both simulated and experimental data are investigated with the proposed AIA approach. It was found that the mass spectra and chromatographic profiles of the components in an overlapping multicomponent GC/MS signal can be accurately resolved with the existence of background, and the results are better than that by using an interactive self-modeling mixture analysis (SIMPLISMA) method. The AIA approach may be a promising tool for the resolution of overlapping GC/MS signal.
文摘We first derive a Darboux transformation for a (2+ 1)-extension of Burgers equation. Then we consider theLie symmetries, symmetry algebra, and symmetry reductions of the equation, and use symmetry reductions to obtaingroup-invariant solutions to the equation.
基金Project supported by the National Key Basic Research Support Foundation (NKBRSF) of China (No. G1999011809) the National Natural Science Foundation of China (No. 49871044).
文摘Soil labile (biologically active) organic carbon fractions under different crop rotation systems in Jiangsu Province, China, were investigated after 10 years of rotation. The rotation systems, including green manurerice-rice (GmRR), wheat-rice-rice (WRR), wheat-rice (WR) and wheat/corn intercrop-rice (WCR) rotations,were established on paddy soils using a randomized complete block design with three replicates. The total organic carbon (TOC), total nitrogen (TN) and water-soluble organic carbon (WSOC) in the soils under different systems were greater in the GmRR and WRR than in the WR and WCR rotation systems because the soils under triple cropping often received more crop residues than the soils under double cropping. Both the WSOC and the microbial biomass carbon (MBC) contents in the soils of the GmRR rotation system were significantly greater than those in the other crop rotation systems, which was due to the return of green manure to the fields of the GmRR rotation system. The results of a 13C nuclear magnetic resonance (13C-NMR) analysis indicated that the structural characteristics of soil WSOC were similar under the four crop rotation systems with carbohydrates and long-chain aliphatics being the major components. Correlation analysis showed that the content of the WSOC was positively correlated with that of the MBC (P <0.01),and all had significantly positive correlations with TOC and TN. The coefficients of variation (CVs) for WSOC and WSOC/TOC were greater than the other indices (e.g, MBC, TOC and TN), suggesting that WSOC in the soils was more sensitive to these rotation systems. The results above indicated that the soil amended with green manure could not only increase the usable C source for soil microorganisms, but could also enhance soil organic matter content; hence, rotation with green manure would be a good strategy for sustainable agriculture.
文摘A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wavelength. The crystal structure of anatase was characterized by XRD. The structure analysis result of X-ray fluorescence(XRF) shows that doped-nitrogen was presented in the sample. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants. The photocatalytic activities of samples were increasing gradually with calcination temperature from 400℃ to 700℃ under UV irradiation. It can be seen that the degradation of methyl orange follows zero-order kinetics. However, the calcination temperatures have no significant influence on the degradation of phenol under sunlight. The N-doped catalyst shows higher activity than the bare one under solar irradiation.
文摘During mitosis, the parent cell distributes its genetic materials equally into two daughter cells through chromosome segregation, a complex movements orchestrated by mitotic kinases and its effector proteins. Faithful chromosome segregation and cytokinesis ensure that each daughter cell receives a full copy of genetic materials of parent cell. Defects in these processes can lead to aneuploidy or polyploidy. Aurora/Ipl1p family, a class of conserved serine/threonine kinases, plays key roles in chromosome segregation and cytokinesis. This article highlights the function and regulation of Aurora/Ipllp family in mitosis and provides potential links between aberrant regulation of Aurora/Ipllp kinases and pathogenesis of human cancer.
文摘We propose two kinds of new Jaynes Cummings models relating to two-photon process by using the supersymmetric unitary transformation. The corresponding energy eigenvalues and eigenvectors are obtained.
文摘We propose two schemes for teleporting an unknown state.In our schemes,a three-particle Greenberger-Hornezeilinger state is used as a quantum channel.We show that the probabilistic teleportation of an unknown quantum atate can be realized.
基金Supported by the National Science Fund for Distinguished Young Scholars,No.30125038the Key Project of National Natural Science Foundation of China,No.30230340the National High Technology Research and Development Program of China(863 Program),No.2002A
文摘AIM: To choose an appropriate methods for the isolation of hepatic lymphocytes between the mechanical dissection and the enzymatic digestion and investigate the effects of two methods on phenotype and function of hepaticlymphocytes.METHODS: Hepatic lymphocytes were isolated from untreated, poly (I:C)-stimulated or ConA-stimulated mice using the two methods, respectively. The cell yield per liver was evaluated by direct counting under microscope.Effects of digestive enzymes on the surface markers involved in hepatic lymphocytes were represented by relative change rate [(percentage of post-digestionpercentage of pre-digestion)/percentage of pre-digestion].Phenotypic analyses of the subpopulations of hepatic lymphocytes and intracellular cytokines were detected by flow cytometry. The cytotoxicity of NK cells from wild C57BL/6 or poly (I:C)-stimulated C57BL/6 mice was analyzed with a 4-h ^51Cr release assay.RESULTS: NK1.1^+ cell markers, NK1.1 and DX5, were significantly down-expressed after enzymatic digestion and their relative change rates were about 28% and 32%,respectively. Compared with the enzymatic digestion, the cell yield isolated from unstimulated, poly (I:C)-treated or ConA-treated mice by mechanical dissection was not significantly decreased. Hepatic lymphocytes isolated by the mechanical dissection comprised more innate immune cells like NK, NKT and γδ cells in normal C57BL/6 mice.After poly (I:C) stimulation, hepatic NK cells rose to about 35%, while NKT cells simultaneously decreased. Following ConA injection, the number of hepatic NKT cells was remarkably reduced to 3.67%. Higher ratio of intracellular IFN-γ^+(68%) or TNF-α^+(15%) NK1.1^+ cells from poly (I:C)treated mice was obtained using mechanical dissection method than control mice. There was no difference in viability between the mechanical dissection and the enzymatic digestion, and hepatic lymphocytes obtained with the two methods had similar cytotoxicity against YAC-1 cells.CONCLUSION: There is no difference in the cell yield and viability of the hepatic lymphocyte isolated with the two methods. The mechanical dissection, but not the enzymatic digestion, may be suitable for the phenotypic analysis of hepatic NK1.1^+ cell.
基金supported by the National Natural Science Foundation of China(Grants 49803002 and 40473007)Program for New Century Excellent Talents in University(NCET)the CAS-CNRS-CNR cooperative project.
文摘Hydrogen isotopic compositions of pyroxenes in peridotite xenoliths from the Nushan volcano, Anhui Province, SE China have been obtained using an ion probe (Cameca 1270). D/H ratios are constant within a single grain and among the different grains from the same sample. The lack of correlation between the D/H ratios and the hydrogen contents indicates that the hydrogen isotopic compositions are inherited from their mantle source. Combining with the δD values of coexisting amphiboles, it is inferred that the Nushan mantle experienced at least a two-stage metasomatic event. One was responsible for formation of amphiboles with extremely variable δD values, and the other was probably responsible for the high δD values (up to ?20‰) of some clinopyroxenes from peridotites, clinopyroxene and mica megacrysts. High δD values point to a subduction-related fluid being involved in one metasomatic event. The primary δD values (?90‰ to ?140‰) of the Nushan pyroxenes, together with data gleaned from the literature, suggest that the D/H ratios of the nominally anhydrous mineral reservoir might have differed from that of the other mantle hydrogen in being relatively depleted in D.
基金This work was supported by the National Natural Seience Foundation of China under gran No.10372098 and 10232030.We would also like to thank the Lab of Mechanical&Materials Science of USTC for their help in the experiments on MTS
文摘The Portevin-Le Chatelier (PLC) effect means serrated yielding or jerky flow phenomenon in some alloys. In this paper a macroscopic model is developed to investigate the PLC effect with the emphasis on mechanical response of the structure evolution on microscopic scale. In addition to the normal work hardening effect, the model takes account of the thermal activation of dislocation moving with the aid of stress and the collective interactions between mobile dislocations and solute atoms due to dynamic strain ageing (DSA). It can satisfy the negative strain rate sensitivity of flow stress, which is believed to be one of the most special features associated with the PLC effect. The heterogeneous nature of the deformed material is also considered by introducing a nonuniform spatial distribution of some model parameters. The serrated yielding and localized deformation behavior can be successfully reproduced via numerical simulation based on this model.
文摘Based on the theory of Markov performance potentials and neuro-dynamic programming(NDP) methodology, we study simulation optimization algorithm for a class of continuous timeMarkov decision processes (CTMDPs) under randomized stationary policies. The proposed algo-rithm will estimate the gradient of average cost performance measure with respect to policy param-eters by transforming a continuous time Markov process into a uniform Markov chain and simula-ting a single sample path of the chain. The goal is to look for a suboptimal randomized stationarypolicy. The algorithm derived here can meet the needs of performance optimization of many diffi-cult systems with large-scale state space. Finally, a numerical example for a controlled Markovprocess is provided.
基金Supported in part by 973 plan and NSF of Zhejiang Province of China(Gl999075105)
文摘We consider the weighted composition operators between Hardy spaces on the unit ball, and obtain some sufficient and necessary conditions of bounded or compact weighted composition operators. We also prove that the operator from H^1 to H^1 is compact if and only if it is weakly compact. Meanwhile, we get the analogue on the Bergman spaces.
文摘Photoacoustic (PA) spectra of powdered neodymium oxide (Nd 2O 3 (A type)), neodymium hydrated chloride (NdCl 3·6H 2O) and neodymium fluoride (NdF 3) were reported. PA band shifts as compared to their positions in aqueous Nd 3+ are used to calculate the nephelauxetic parameters of the compounds. The variation of these parameters and correlation with the nature of metal ligand bonding were discussed. A novel method is introduced to determine the relative values of oscillator strengths and Judd Ofelt parameters of powdered samples using PA spectroscopy. It is found that a linear correlation exists between relative values of τ 2 and oscillator strengths of hypersensitive transitions of the title compounds. It is hopetul that the new method of PA technique may serve for the Judd Ofelt quantitative analysis of powdered rare earth compounds.
基金the financial supports from the National Natural Science Foundation of China(No.20703042)National Basic Research Program of China(No.2010CB923300)+1 种基金USTC-NSRL Association Funding(No.KY2060030009)the Fundamental Research Funds for the Central Universities
文摘The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption spectroscopy.The catalytic property was strongly influenced by the Fe substitution.The relation between catalytic performance and the degree of Fe substitution was examined with regard to the structure and surface characteristics of the mixed oxides.The Fe-containing catalysts exhibited higher activity attributable to the possible(Fe2+,Mo6+) and (Fe3+,Mo5+)valency pairs,and the highest activity was observed for Sr2Mg0.2Fe0.8MoO6-δ.The enhancement of the catalytic activity may be correlated with the Fe-relating surface lattice oxygen species and was discussed in view of the presence of oxygen vacancies.
文摘For the first time, we apply different geospeedometric models to garnet zoning patterns that were obtained in this study from detailed EMP analyses for garnets from eclogites and granulite in the Dabie-Sulu orogen. Various zonings of cation diffusion were preserved in the garnets, enabling the acquirement of average cooling rates for the high-to ultrahigh-pressure rocks without using geochronological approaches. The coesite-bearing hot eclogites yield fast cooling rates of about 20 to 30℃/Ma subsequent to peak metamorphic temperatures, whereas the cold eclogite gives a relatively slow cooling rate of 8℃/Ma at its initial exhumation. A very slow cooling rate of <0.3℃/Ma is obtained for the granulite at Huangtuling, suggesting that the granulite may not be involved in the continental deep subduction.
文摘The direct method proposed by Clarkson and Kruskal is modified to obtain some conditional similarity solutions of a nonlinear physics model. Taking the -dimensional Boussinesq equation as a simple example, six types of conditional similarity reductions are obtained.
文摘Radar remote sensing can acquire information of sub-surface covered by sand in arid area, detect surface roughness and vegetation coronet's layer and linear feature such as linear structure and channel sensitively. With sediment facies analysis, this paper studies the features of environmental evolution in mid-late Epipleistocene (60 ka BP-20 ka BP) in northeastern Ejin Banner. The conclusions are listed as follows: (1) The evolution of the three lakes, i.e. Gaxunnur, Sugunur and Tian'e lakes, are dominated by faults and regional climate. (2) By analyzing sedimentary section of old Juyanze Lake, the three lakes used to be a large outflow lake before 50 ka BP in northeastern Ejin Banner, and at 50 ka BP, temperature declined rapidly in northwestern China. The event caused the lake's shrinkage. (3) By fault activity uplift in the northern part of old Juyan Lake and depression in the southern part, the lake's water followed from north to south at around 35 ka BP, old Juyanze fluvial fan was formed. At the same time, Juyan Lake separated from Sugunur Lake and Wentugunr old channel was abandoned. (4) In recent 2000 years, Ruoshui River is a wandering river, sometimes it flows into Juyan Lake and sometimes Sugunur and Gaxunnur lakes. Due to human activities and over exploitation, the oasis ecosystem is rapidly degenerated in 15 years (1986-2000).
基金supported partly by Outstanding Young Scientist Award and Key Project by Natural Science Foundation of China(No.30125038,No.30230340)The Major Sate Basic research Development program of China(No.2001CB510009)+1 种基金The National high technology research and Development program of China(No.2002AA216151)by Ministry of Science and Technology of ChinaKey Project by Chinese Academy of Science(No.KSCX2-2-08).
文摘We have previously shown a critical role of prolactin (PRL) during maturation and anti-tumor effects of murine natural killer (NK) cells in vitro and in vivo. We extended that study by exploring the ability of human NK cell lines (NK-92 and YT cell) to express PRL receptor (PRL-R) and to respond to PRL stimulation in vitro. Both human NK cell lines constitutively expressed PRL-R on membrane and mRNA transcripts,NK-92 cells contained higher level of PRL-R than YT cells,which correlated to the enhanced capacity of the cells to proliferate and to lyse target cells in response to PRL stimulation in the presence of trace amount of IL-2 or IL-15 in vitro. Two differences between IL-2 and IL-15 in functioning on human NK cells were for the first time observed. PRL synergized with IL-15 to improve proliferation of NK cells in a dose-dependent manner without double peak manifesting like IL-2. Although PRL enhanced the cytotoxicity of IL-2 or IL- 15 activated NK cells,it exerted the function through up-regulating gene expression of perforin without influence of FasL in IL-2-stimulated NK cells,while in IL-15-stimulated NK cells,PRL did the function through up-regulating gene expression of both perforin and FasL but not IFNγ. PRL increased expressions of IL-2Rα on membrane and of IL-2 mRNA in cells,indicating that PRL up-regulated NK cell function by improving positive feedback between IL-2 and IL-2R. The similar results were also observed in network between IL-15 and IL-15R. These data indicate a potential role of PRL in human NK cell modulation.