The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and surface data was discussed in this paper. The procedure...The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and surface data was discussed in this paper. The procedure was: (1) annual maximum normalized difference vegetation index (NDVI) over the landscape was calculated from TM images; (2) the relationship model between NDVI and LAI was built and annual maximum LAI over the landscape was simulated; (3) the relationship models between LAI and biomass were built and annual branch, stem, root and maximum leaf biomass over the landscape were simulated; (4) spatial distribution patterns of leaf biomass and LAI in different periods all the year round were obtained. The simulation was based on spatial analysis module GRID in ArcInfo software. The method is also a kind of scaling method from patch scale to landscape scale. A case study of Changbai Mountain Nature Reserve was dissertated. Analysis and primary validation were carried out to the simulated LAI and biomass for the major vegetation types in the Changbai Mountain in 1995.展开更多
The singularly perturbed generalized boundary value problems for semi-linear elliptic equations of fourth order are considered. Under suitable conditions the existence, uniqueness and asymptotic behavior of generalize...The singularly perturbed generalized boundary value problems for semi-linear elliptic equations of fourth order are considered. Under suitable conditions the existence, uniqueness and asymptotic behavior of generalized solutions for the boundary value problems are studied.展开更多
Aim To explore the correlation of stem cell factor (SCF)and monocyte chemoattractant protein-1 (MCP-1) with number difference of mast cell (MC) around the liver tumor.Methods 40 male wistar rats with liver neoplasm we...Aim To explore the correlation of stem cell factor (SCF)and monocyte chemoattractant protein-1 (MCP-1) with number difference of mast cell (MC) around the liver tumor.Methods 40 male wistar rats with liver neoplasm were divided into three different groups by numbers of MC in the surroundings of tumor. We performed ELISA for SCF and MCP-1 in serums. And chemotaxis assays of rat peritoneal MCs to SCF and MCP-1 in serums were measured in 48-wellmicroboyden chambers. We also used immunohistochemistryto investigate whether rat MCs express SCF positively.RESULTE There were marked differences in MC numbersaround tumor between different groups. The group that has more MCs around tumor has the higher levels of SCF andMCP-1 in serums and the stronger chemotaxis to ratperitoneal MCs. SCF washigher than MCP-1 in bothchemotactic activity to MCs and levels in serums. And ratMCs positively express SCF.Conclusion SCF and MCP-1 were found to be two particularly efficacious chemoattractants for MCs. The levels of SCF and MCP-1 in serums may be closely correlated with MCs numbers around tumor. The production of SCF by MCs might act on mast cell migration and proliferation of MC.展开更多
A 2.4-m-long core was extracted from Diaojiao Lake (41?8′N, 112?1′E) at the foot of the northern part of Daqingshan Mts. High-resolution pollen analysis results of two sites showed 10 arboreal genera, including Pinu...A 2.4-m-long core was extracted from Diaojiao Lake (41?8′N, 112?1′E) at the foot of the northern part of Daqingshan Mts. High-resolution pollen analysis results of two sites showed 10 arboreal genera, including Pinus, Betula, Picea, Abies, Carpinus, Quercus, Ulmus and more than 20 non-arboreal genera, mainly of Artemisia, Labiatae, Nitraria, Polygonaceae, Ranunculus, Thalictrum, Umbelliferae, Caryophyllaceae and Cyperaceae dominating the record. Fern spores, aquatic pollen and algae were also observed in some sections of the cores. The sequence was divided stratigraphically into six pollen assemblage zones by a stratigraphically-constrained cluster analysis using an incremental sum of squares method. The vegetation underwent the following stage changes: steppe with sparse trees, steppe, forest, and steppe. During the middle Holocene, a mixed forest of Pinus, Betula and Quercus occurred on the mountainous areas, and Pinus forest dominated the frontal plains. Six climatic stages were inferred from total pollen flux and pollen percentage from the two sites using a transfer function: humid-cool (10000—7800 aBP), arid-cold (9200—7800 aBP), arid-warm (7800—7100 aBP), humid-warm (7100—4400 aBP), arid-warm (4400—3000 aBP), arid-cold (3000—2100 aBP) phases were identified.展开更多
Tools for pair-wise bio-sequence alignment have for long played a central role in computation biology. Several algorithms for bio-sequence alignment have been developed. The Smith-Waterman algorithm, based on dynamic ...Tools for pair-wise bio-sequence alignment have for long played a central role in computation biology. Several algorithms for bio-sequence alignment have been developed. The Smith-Waterman algorithm, based on dynamic programming, is considered the most fundamental alignment algorithm in bioinformatics. However the existing parallel Smith-Waterman algorithm needs large memory space, and this disadvantage limits the size of a sequence to be handled. As the data of biological sequences expand rapidly, the memory requirement of the existing parallel Smith- Waterman algorithm has become a critical problem. For solving this problem, we develop a new parallel bio-sequence alignment algorithm, using the strategy of divide and conquer, named PSW-DC algorithm. In our algorithm, first, we partition the query sequence into several subsequences and distribute them to every processor respectively, then compare each subsequence with the whole subject sequence in parallel, using the Smith-Waterman algorithm, and get an interim result, finally obtain the optimal alignment between the query sequence and subject sequence, through the special combination and extension method. Memory space required in our algorithm is reduced significantly in comparison with existing ones. We also develop a key technique of combination and extension, named the C&E method, to manipulate the interim results and obtain the final sequences alignment. We implement the new parallel bio-sequences alignment algorithm, the PSW-DC, in a cluster parallel system.展开更多
We present in this paper a generalised PC (GPC) equation which includesseveral known models. The corresponding traveling wave system is derived and we show that thehomoclinic orbits of the traveling wave system corres...We present in this paper a generalised PC (GPC) equation which includesseveral known models. The corresponding traveling wave system is derived and we show that thehomoclinic orbits of the traveling wave system correspond to the solitary waves of GPC equation, andthe heteroclnic orbits correspond to the kink waves. Under some parameter conditions, the existenceof above two types of orbits is demonstrated and the explicit expressions of the two solutions areworked out.展开更多
In this paper, we consider the Cauchy problem for some dispersive equations. By means of nonlinear estimate in Besov spaces and fixed point theory, we prove the global well-posedness of the above problem. What's m...In this paper, we consider the Cauchy problem for some dispersive equations. By means of nonlinear estimate in Besov spaces and fixed point theory, we prove the global well-posedness of the above problem. What's more, we improve the scattering result obtained in [1].展开更多
基金One Hundred Talents Program of CAS No.CXIOG-C00-01+1 种基金 National Natural Science Foundation of China No.39970613
文摘The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and surface data was discussed in this paper. The procedure was: (1) annual maximum normalized difference vegetation index (NDVI) over the landscape was calculated from TM images; (2) the relationship model between NDVI and LAI was built and annual maximum LAI over the landscape was simulated; (3) the relationship models between LAI and biomass were built and annual branch, stem, root and maximum leaf biomass over the landscape were simulated; (4) spatial distribution patterns of leaf biomass and LAI in different periods all the year round were obtained. The simulation was based on spatial analysis module GRID in ArcInfo software. The method is also a kind of scaling method from patch scale to landscape scale. A case study of Changbai Mountain Nature Reserve was dissertated. Analysis and primary validation were carried out to the simulated LAI and biomass for the major vegetation types in the Changbai Mountain in 1995.
基金The Hundred People Project of Chinese Academy of Sciences.
文摘The singularly perturbed generalized boundary value problems for semi-linear elliptic equations of fourth order are considered. Under suitable conditions the existence, uniqueness and asymptotic behavior of generalized solutions for the boundary value problems are studied.
文摘Aim To explore the correlation of stem cell factor (SCF)and monocyte chemoattractant protein-1 (MCP-1) with number difference of mast cell (MC) around the liver tumor.Methods 40 male wistar rats with liver neoplasm were divided into three different groups by numbers of MC in the surroundings of tumor. We performed ELISA for SCF and MCP-1 in serums. And chemotaxis assays of rat peritoneal MCs to SCF and MCP-1 in serums were measured in 48-wellmicroboyden chambers. We also used immunohistochemistryto investigate whether rat MCs express SCF positively.RESULTE There were marked differences in MC numbersaround tumor between different groups. The group that has more MCs around tumor has the higher levels of SCF andMCP-1 in serums and the stronger chemotaxis to ratperitoneal MCs. SCF washigher than MCP-1 in bothchemotactic activity to MCs and levels in serums. And ratMCs positively express SCF.Conclusion SCF and MCP-1 were found to be two particularly efficacious chemoattractants for MCs. The levels of SCF and MCP-1 in serums may be closely correlated with MCs numbers around tumor. The production of SCF by MCs might act on mast cell migration and proliferation of MC.
基金supported by the National Key Basic Research Support Foundation Project(Grant No.G2000018604).
文摘A 2.4-m-long core was extracted from Diaojiao Lake (41?8′N, 112?1′E) at the foot of the northern part of Daqingshan Mts. High-resolution pollen analysis results of two sites showed 10 arboreal genera, including Pinus, Betula, Picea, Abies, Carpinus, Quercus, Ulmus and more than 20 non-arboreal genera, mainly of Artemisia, Labiatae, Nitraria, Polygonaceae, Ranunculus, Thalictrum, Umbelliferae, Caryophyllaceae and Cyperaceae dominating the record. Fern spores, aquatic pollen and algae were also observed in some sections of the cores. The sequence was divided stratigraphically into six pollen assemblage zones by a stratigraphically-constrained cluster analysis using an incremental sum of squares method. The vegetation underwent the following stage changes: steppe with sparse trees, steppe, forest, and steppe. During the middle Holocene, a mixed forest of Pinus, Betula and Quercus occurred on the mountainous areas, and Pinus forest dominated the frontal plains. Six climatic stages were inferred from total pollen flux and pollen percentage from the two sites using a transfer function: humid-cool (10000—7800 aBP), arid-cold (9200—7800 aBP), arid-warm (7800—7100 aBP), humid-warm (7100—4400 aBP), arid-warm (4400—3000 aBP), arid-cold (3000—2100 aBP) phases were identified.
文摘Tools for pair-wise bio-sequence alignment have for long played a central role in computation biology. Several algorithms for bio-sequence alignment have been developed. The Smith-Waterman algorithm, based on dynamic programming, is considered the most fundamental alignment algorithm in bioinformatics. However the existing parallel Smith-Waterman algorithm needs large memory space, and this disadvantage limits the size of a sequence to be handled. As the data of biological sequences expand rapidly, the memory requirement of the existing parallel Smith- Waterman algorithm has become a critical problem. For solving this problem, we develop a new parallel bio-sequence alignment algorithm, using the strategy of divide and conquer, named PSW-DC algorithm. In our algorithm, first, we partition the query sequence into several subsequences and distribute them to every processor respectively, then compare each subsequence with the whole subject sequence in parallel, using the Smith-Waterman algorithm, and get an interim result, finally obtain the optimal alignment between the query sequence and subject sequence, through the special combination and extension method. Memory space required in our algorithm is reduced significantly in comparison with existing ones. We also develop a key technique of combination and extension, named the C&E method, to manipulate the interim results and obtain the final sequences alignment. We implement the new parallel bio-sequences alignment algorithm, the PSW-DC, in a cluster parallel system.
文摘We present in this paper a generalised PC (GPC) equation which includesseveral known models. The corresponding traveling wave system is derived and we show that thehomoclinic orbits of the traveling wave system correspond to the solitary waves of GPC equation, andthe heteroclnic orbits correspond to the kink waves. Under some parameter conditions, the existenceof above two types of orbits is demonstrated and the explicit expressions of the two solutions areworked out.
文摘In this paper, we consider the Cauchy problem for some dispersive equations. By means of nonlinear estimate in Besov spaces and fixed point theory, we prove the global well-posedness of the above problem. What's more, we improve the scattering result obtained in [1].
