Due to their special phylogenetic position in the Euarchontoglires and close affinity to primates,tree shrews have been proposed as an alternative experimental animal to primates in biomedical research.However,the pop...Due to their special phylogenetic position in the Euarchontoglires and close affinity to primates,tree shrews have been proposed as an alternative experimental animal to primates in biomedical research.However,the population genetic structure of tree shrews has largely remained unknown and this has hindered the development of tree shrew breeding and selection.Here we sampled 80 Chinese tree shrews(Tupaia belangeri chinensis) in Kunming,China,and analyzed partial mtDNA control region sequence variation.Based on our samples and two published sequences from northern tree shrews(T.belangeri),we identified 29 substitutions in the mtDNA control region fragment(~ 604 bp) across 82 individuals and defined 13 haplotypes.Seventeen samples were selected for sequencing of the cytochrome b(Cyt b;1134 bp) gene based on control region sequence variation and were analyzed in combination with 34 published sequences to solidify the phylogenetic pattern obtained from control region data.Overall,tree shrews from Kunming have high genetic diversity and present a remarkable long genetic distance to the two reported northern tree shrews outside China.Our results provide some caution when using tree shrews to establish animal models because of this apparent genetic difference.In addition,the high genetic diversity of Chinese tree shrews inhabiting Kunming suggests that systematic genetic investigations should be conducted before establishing an inbred strain for medical and biological research.展开更多
Partial eytochrome oxidase subunits I (COI) and II (COII), and cytochrome b (Cyt b) genes of thirteen species of the ant genus Formica were sequenced for molecular phylogenetic studies. The sequences were as fol...Partial eytochrome oxidase subunits I (COI) and II (COII), and cytochrome b (Cyt b) genes of thirteen species of the ant genus Formica were sequenced for molecular phylogenetic studies. The sequences were as follows: COI fragment, 657 bp; COl + COIl fragments, approximately 900 bp, including the termination codon at the end of COI and the initiator codon at the beginning of COIl; and the Cyt b fragment, 777 bp. Results show that these three mitoehondrial genetic markers are similar in base composition. The contents of A + T were 73.8% (COl) and 79.2% (COII)--higher than those of G + C, which were 20.8% (COIl) and 26.2% (COI), and strongly AT-biased. The highest A + T contents were 89.9% (COI) and 93.7% (COII) on the third codon, whereas the lowest G content was 0.2% (COII) and 1.2% (Cyt b). Molecular phylogenetic trees based on these mitoehondrial genes were reconstructed. Cataglyphis aenescens in the subfamily Formicinae was used as the outgroup, and Diacamma rugosum of the subfamily Ponerinae was used as an additional, distantly-related outgroup. Phylogenetic analysis showed that the differences among the species in the in-group were small, with genetic distance values less than 0.1. The greatest genetic distance was between E beijingensis and F. cunicularia. The results are in accord with those based on morphological features.展开更多
Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coeffici...Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio (SNR) seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks.展开更多
Community plays an important role in the preservation of agricultural heritage system (AHS). Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism devel...Community plays an important role in the preservation of agricultural heritage system (AHS). Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism development (TD) can be supportive for the conservation of AHS while creating benefits for local communities. In this study, two mountainous pilot villages (Longxian and Xiaohuang) in a global conservation project for traditional agricutural systems - Globally Important Agricultural Heritage Systems (GIAHS) were selected to identify the relationship between AHS conservation and TD. The study undertook in-depth interviews, and questionnaires of village residents and informal discussions with local villagers. A t-test and a linear regression model were implemented to explore the comparative dimensions of the two communities with different geographical location, economic situation, and stage of TD. The research found some similarities and differences in the two mountainous communities during AHS conservation and TD. Firstly, AHS are preservaed well in both villages unconsiously, while the residents in Xiaohuang value more highly the heritage elements than the respondents in Longxian, and the villagers in Xiaohuang are more worried about their heritage system; Secondly, both villages expect lots of benefits from TD and they clearly perceive more positive than negative impact from tourism and thus approve TD, while the hugedifferent perception on transportation and accessibility in the two villages reflects the bottleneck of TD in Xiaohuang village. At the same time, the respondents from Xiaohuang perceive more positive and fewer negative impact from tourism than the respondents from Longxian. Thirdly, the respondents in the two villages all show positive attitudes towards participation in tourism mostly motivated by the high income expectation. The main factors to determine the community perception in two villages were also analyzed based on the data process. A location-based coneeputal framework of AHS conservation in partnership with TD at community scale is proposed at the end of the paper. The dynamics of tourism development, that could enhance a better understanding of the complex relationship between conservation objectives and tourism development are discussed.展开更多
The authors exploit the remarkable connection between the Chinese climate trends and the annular modes by partitioning the trends into components linearly congruent with and linearly independent of the annular modes. ...The authors exploit the remarkable connection between the Chinese climate trends and the annular modes by partitioning the trends into components linearly congruent with and linearly independent of the annular modes. Results show that the winter hemisphere annular mode has closer connection to Chinese climate than the summer one, e.g., the wetting JJA (June-July-August) rainfall trend along the Yangtze River valley and the associated temperature trends are significantly linearly congruent with the trend of the southern annular mode, while the JFM (January-February-March) climate trends are closely linked to the northern annular mode. The seasonal differences of a meridional wave-train-like chain across the equatorial Pacific associated with the annular modes are responsible for the seasonal-dependent connections to Chinese climate.展开更多
Based on the 1990, 2000 and 2011 Landsat TM/ETM+ remote sensing data, glacier information of three periods in the Chinese Tianshan Mountains were extracted by using ratio threshold method(TM3/TM5) and visual interpret...Based on the 1990, 2000 and 2011 Landsat TM/ETM+ remote sensing data, glacier information of three periods in the Chinese Tianshan Mountains were extracted by using ratio threshold method(TM3/TM5) and visual interpretation, combined with digital processing of satellite images and analysis in GIS. The climate data in the surrounding area were analyzed by using linear regression, Mann-Kendall abrupt test, and Morlet wavelet analysis. Study results showed that: over the 23 years investigation, the glacier areas have markedly decreased. In the last 12 years(2000 to 2011), the rate of retreat has begun to accelerate. The most dramatic glacier shrinkage occurred in the central region, the lowest in the eastern region. The mean summer temperature and warm precipitation in Chinese Tianshan Mountains had an increasing trend, with rates of 0.22°C /10 a and 5.1mm/10 a from 1960 to 2011, respectively. Mean summer temperature have experienced a strong increase in 1998. The analysis of the results showed that the rise of mean summer temperature was the main factor that contributed to glacier shrinkage. Regional differences of glacier area changes were investigated by analyzing glacier behavior in five study sub-regions; regional differences are related to local climate, to the relative proportion of glaciers in different size classes, altitudinal and aspect distribution of glaciated areas. In addition, the lag theory indicated that glaciers may accelerate the retreat in the next decade, considering climate trends recognized for the period 2000-2011.展开更多
Low Carbon Employment is an inevitable choice for the purpose of "energy-saving and emission reduction" and "promoting employment". By Multi-variable Linear Backward Regression method, this study presents an empir...Low Carbon Employment is an inevitable choice for the purpose of "energy-saving and emission reduction" and "promoting employment". By Multi-variable Linear Backward Regression method, this study presents an empirical analysis of the emplovment impact of policy variables indexes that involves economic pull, industry upgrading, population development, technical inputs and so on. The paper demonstrates that wide range offactors will affect low carbon employment, that industry upgrading will affect how carbon employment remarkably, that to increase years of people education will notably improve low carbon employment level of secondary vocational-technical labor, and that to raise technical inputs will significantly enhance college students' low carbon employment.展开更多
The main aim of this paper was to calculate soil organic carbon stock(SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China.A novel prediction process ...The main aim of this paper was to calculate soil organic carbon stock(SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China.A novel prediction process was presented and was referred to as model-then-calculate with respect to the variable thicknesses of soil horizons(MCV).The model-then-calculate with fixed-thickness(MCF),soil profile statistics(SPS),pedological professional knowledge-based(PKB) and vegetation type-based(Veg) methods were carried out for comparison.With respect to the similar pedological information,nine common layers from topsoil to bedrock were grouped in the MCV.Validation results suggested that the MCV method generated better performance than the other methods considered.For the comparison of polygon based approaches,the Veg method generated better accuracy than both SPS and PKB,as limited soil data were incorporated.Additional prediction of the pedogenetic horizons within MCV benefitted the regional SOCS estimation and provided information for future soil classification and understanding of soil functions.The intermediate product,that is,horizon thickness maps were fluctuant enough and reflected many details in space.The linear mixed model indicated that mean annual air temperature(MAAT) was the most important predictor for the SOCS simulation.The minimal residual of the linear mixed models was achieved in the vegetation type-based model,whereas the maximal residual was fitted in the soil type-based model.About 95% of SOCS could be found in Argosols,Cambosols and Isohumosols.The largest SOCS was found in the croplands with vegetation of Triticum aestivum L.,Sorghum bicolor(L.) Moench,Glycine max(L.) Merr.,Zea mays L.and Setaria italica(L.) P.Beauv.展开更多
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper"How long is the coastline of Britain?"published in "Science" in 1967. The fractal concept was presented for the first...MANDELBROT enunciated the uncertainty of the length of a coastline in his paper"How long is the coastline of Britain?"published in "Science" in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. According to the fractal theory and conditions of fractal research of coastline,the controls of faults and biologic function on the fractal character of coastline are preliminarily discussed on the basis of GIS in this paper . Finally,some significant conclusions are drawn:1)the faults control the basic trends of coastlines of two study areas;2)the fractal dimension of coastline of Taiwan is smaller than that of Changle-Lufeng,because the faults of Taiwan more intensely control the trend and fractal dimension of the coastline;3)the larger the fractal dimension of the faults or the major faults,the more the controlling effect of them on the trend and fractal dimension of coastline; 4)the larger fractal dimension of the coastline of Changle-Lufeng indicates that the biologic function intensely shapes the coastline. In a word,the controls of faults and biologic function on the fractal character of coastline are discussed with a case study of China in this paper,it can be seen that faults and biologic function both have influence over the trend and fractal dimension of coastline,the fractal mechanism of coastline of two study areas may be so.展开更多
The complete mitochondrial cytochrome oxidase subunit Ⅱ (COⅡ) gene of Penaeinae shrimp Fenneropenaeus chinensis was cloned and sequenced. The gene is 688 bp in length and codes for 229 amino acids. It shows 83.2%,...The complete mitochondrial cytochrome oxidase subunit Ⅱ (COⅡ) gene of Penaeinae shrimp Fenneropenaeus chinensis was cloned and sequenced. The gene is 688 bp in length and codes for 229 amino acids. It shows 83.2%, 87.0% and 83.8% sequence similarity to Marsupenaeus Japonicus, Penaeus monodon and Farfantepenaeus notialis, respectively. The A+T content of the whole gene and that at the third position of codons are 64.7% and 78.2%, respectively. The phylogenetic relationship between F. chinensis and three other species representing genera Farfanatepenaeus, Marsupenaeus and Penaeus was analyzed. Results showed that the genetic distances among the four taxa ranged from 0.144 0 to 0.200 5, exceeding those estimated with COⅠ and partial 16S rRNA gene sequences among Marsupenaeus, Litopenaeus and Melicertus, and being therefore larger than the value among subgenera. It has been suggested that the COⅡ gene has a faster evolutionary rate than that of the COⅠ gene and partial 16S rRNA gene and could be used for phylogenetic analysis at genus or species level. The results of the present study indicated that Farfantepenaeus, Fenneropenaeus, Marsupenaeus and Penaeus are at a higher phylogenetic level than subgenus, which supports the opinion of the elevation of phylogenetic status of the four subgenera to genus level.展开更多
The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing ...The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing a high efficient and low cost network multi-well data management architecture based on the General Logging Curve Theory and the Cif data format; 2, implementing efficient visit and transmission of multi-well data in C/S local network based on TCP/IP protocol; 3,ensuring the safety of multi-well data in store, visit and application based on Unix operating system security. By using CifNet system, the researcher in office or at home can visit curves of any borehole in any working area of any oilfield. The application foreground of CifNet system is also commented.展开更多
基金supported by grants from Yunnan Province (2009CI119)the Chinese Academy of Sciences (KSCX2-EW-R-11 and KSCX2-EW-J-23)the Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province
文摘Due to their special phylogenetic position in the Euarchontoglires and close affinity to primates,tree shrews have been proposed as an alternative experimental animal to primates in biomedical research.However,the population genetic structure of tree shrews has largely remained unknown and this has hindered the development of tree shrew breeding and selection.Here we sampled 80 Chinese tree shrews(Tupaia belangeri chinensis) in Kunming,China,and analyzed partial mtDNA control region sequence variation.Based on our samples and two published sequences from northern tree shrews(T.belangeri),we identified 29 substitutions in the mtDNA control region fragment(~ 604 bp) across 82 individuals and defined 13 haplotypes.Seventeen samples were selected for sequencing of the cytochrome b(Cyt b;1134 bp) gene based on control region sequence variation and were analyzed in combination with 34 published sequences to solidify the phylogenetic pattern obtained from control region data.Overall,tree shrews from Kunming have high genetic diversity and present a remarkable long genetic distance to the two reported northern tree shrews outside China.Our results provide some caution when using tree shrews to establish animal models because of this apparent genetic difference.In addition,the high genetic diversity of Chinese tree shrews inhabiting Kunming suggests that systematic genetic investigations should be conducted before establishing an inbred strain for medical and biological research.
基金supported by the National Natural Science Foundation of China (30770258, 31071971)the Foundation of Guangxi Key Laboratory of Rare and Endangered Animal Ecology, Guangxi Normal University (1301Z001)
文摘Partial eytochrome oxidase subunits I (COI) and II (COII), and cytochrome b (Cyt b) genes of thirteen species of the ant genus Formica were sequenced for molecular phylogenetic studies. The sequences were as follows: COI fragment, 657 bp; COl + COIl fragments, approximately 900 bp, including the termination codon at the end of COI and the initiator codon at the beginning of COIl; and the Cyt b fragment, 777 bp. Results show that these three mitoehondrial genetic markers are similar in base composition. The contents of A + T were 73.8% (COl) and 79.2% (COII)--higher than those of G + C, which were 20.8% (COIl) and 26.2% (COI), and strongly AT-biased. The highest A + T contents were 89.9% (COI) and 93.7% (COII) on the third codon, whereas the lowest G content was 0.2% (COII) and 1.2% (Cyt b). Molecular phylogenetic trees based on these mitoehondrial genes were reconstructed. Cataglyphis aenescens in the subfamily Formicinae was used as the outgroup, and Diacamma rugosum of the subfamily Ponerinae was used as an additional, distantly-related outgroup. Phylogenetic analysis showed that the differences among the species in the in-group were small, with genetic distance values less than 0.1. The greatest genetic distance was between E beijingensis and F. cunicularia. The results are in accord with those based on morphological features.
基金This paper is supported by China Petrochemical Key Project in the"11th Five-Year"Plan Technology and the Doctorate Fund of Ministry of Education of China (No.20050491504)
文摘Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio (SNR) seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks.
基金supported by the China National Natural Science Foundation (Grant Nos. 41201580, 40121553, 41201586)the research project on heritage tourism from China National Tourism Administration to Dr. Sun Ye-hong (Grant No. 13TAAG014)+2 种基金project of Construction of Innovative Teams and Teacher Career Development for Universities and Colleges under Beijing Municipality (Grant No. IDHT20130513)the international project of "GEF-FAO/GIAHS dynamic conservation and adaptive management", a research program at the Institute of Geographic SciencesNatural Resources Research of the Chinese Academy of Sciences
文摘Community plays an important role in the preservation of agricultural heritage system (AHS). Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism development (TD) can be supportive for the conservation of AHS while creating benefits for local communities. In this study, two mountainous pilot villages (Longxian and Xiaohuang) in a global conservation project for traditional agricutural systems - Globally Important Agricultural Heritage Systems (GIAHS) were selected to identify the relationship between AHS conservation and TD. The study undertook in-depth interviews, and questionnaires of village residents and informal discussions with local villagers. A t-test and a linear regression model were implemented to explore the comparative dimensions of the two communities with different geographical location, economic situation, and stage of TD. The research found some similarities and differences in the two mountainous communities during AHS conservation and TD. Firstly, AHS are preservaed well in both villages unconsiously, while the residents in Xiaohuang value more highly the heritage elements than the respondents in Longxian, and the villagers in Xiaohuang are more worried about their heritage system; Secondly, both villages expect lots of benefits from TD and they clearly perceive more positive than negative impact from tourism and thus approve TD, while the hugedifferent perception on transportation and accessibility in the two villages reflects the bottleneck of TD in Xiaohuang village. At the same time, the respondents from Xiaohuang perceive more positive and fewer negative impact from tourism than the respondents from Longxian. Thirdly, the respondents in the two villages all show positive attitudes towards participation in tourism mostly motivated by the high income expectation. The main factors to determine the community perception in two villages were also analyzed based on the data process. A location-based coneeputal framework of AHS conservation in partnership with TD at community scale is proposed at the end of the paper. The dynamics of tourism development, that could enhance a better understanding of the complex relationship between conservation objectives and tourism development are discussed.
基金supported by the Major State Basic Research Development Program of China (973 Program) under grant No. 2005CB321703the National Natural Science Foundation of China under Grant Nos. 40523001, 40221503, and 40625014the China Meteorological Administration under Grant No. GYHY200706010
文摘The authors exploit the remarkable connection between the Chinese climate trends and the annular modes by partitioning the trends into components linearly congruent with and linearly independent of the annular modes. Results show that the winter hemisphere annular mode has closer connection to Chinese climate than the summer one, e.g., the wetting JJA (June-July-August) rainfall trend along the Yangtze River valley and the associated temperature trends are significantly linearly congruent with the trend of the southern annular mode, while the JFM (January-February-March) climate trends are closely linked to the northern annular mode. The seasonal differences of a meridional wave-train-like chain across the equatorial Pacific associated with the annular modes are responsible for the seasonal-dependent connections to Chinese climate.
基金supported by the National Science Foundation of China (Grant No. 41271024)the Fund Project for National Basic Science Talents Cultivation (Grant No. J1210065)the Fundamental Research Funds for the Central Universities- Excellent Graduate Innovation Project (Grant No. Lzujbky-2014-274)
文摘Based on the 1990, 2000 and 2011 Landsat TM/ETM+ remote sensing data, glacier information of three periods in the Chinese Tianshan Mountains were extracted by using ratio threshold method(TM3/TM5) and visual interpretation, combined with digital processing of satellite images and analysis in GIS. The climate data in the surrounding area were analyzed by using linear regression, Mann-Kendall abrupt test, and Morlet wavelet analysis. Study results showed that: over the 23 years investigation, the glacier areas have markedly decreased. In the last 12 years(2000 to 2011), the rate of retreat has begun to accelerate. The most dramatic glacier shrinkage occurred in the central region, the lowest in the eastern region. The mean summer temperature and warm precipitation in Chinese Tianshan Mountains had an increasing trend, with rates of 0.22°C /10 a and 5.1mm/10 a from 1960 to 2011, respectively. Mean summer temperature have experienced a strong increase in 1998. The analysis of the results showed that the rise of mean summer temperature was the main factor that contributed to glacier shrinkage. Regional differences of glacier area changes were investigated by analyzing glacier behavior in five study sub-regions; regional differences are related to local climate, to the relative proportion of glaciers in different size classes, altitudinal and aspect distribution of glaciated areas. In addition, the lag theory indicated that glaciers may accelerate the retreat in the next decade, considering climate trends recognized for the period 2000-2011.
文摘Low Carbon Employment is an inevitable choice for the purpose of "energy-saving and emission reduction" and "promoting employment". By Multi-variable Linear Backward Regression method, this study presents an empirical analysis of the emplovment impact of policy variables indexes that involves economic pull, industry upgrading, population development, technical inputs and so on. The paper demonstrates that wide range offactors will affect low carbon employment, that industry upgrading will affect how carbon employment remarkably, that to increase years of people education will notably improve low carbon employment level of secondary vocational-technical labor, and that to raise technical inputs will significantly enhance college students' low carbon employment.
基金Under the auspices of Basic Project of State Commission of Science Technology of China(No.2008FY110600)National Natural Science Foundation of China(No.91325301,41401237,41571212,41371224)Field Frontier Program of Institute of Soil Science,Chinese Academy of Sciences(No.ISSASIP1624)
文摘The main aim of this paper was to calculate soil organic carbon stock(SOCS) with consideration of the pedogenetic horizons using expert knowledge and GIS-based methods in northeastern China.A novel prediction process was presented and was referred to as model-then-calculate with respect to the variable thicknesses of soil horizons(MCV).The model-then-calculate with fixed-thickness(MCF),soil profile statistics(SPS),pedological professional knowledge-based(PKB) and vegetation type-based(Veg) methods were carried out for comparison.With respect to the similar pedological information,nine common layers from topsoil to bedrock were grouped in the MCV.Validation results suggested that the MCV method generated better performance than the other methods considered.For the comparison of polygon based approaches,the Veg method generated better accuracy than both SPS and PKB,as limited soil data were incorporated.Additional prediction of the pedogenetic horizons within MCV benefitted the regional SOCS estimation and provided information for future soil classification and understanding of soil functions.The intermediate product,that is,horizon thickness maps were fluctuant enough and reflected many details in space.The linear mixed model indicated that mean annual air temperature(MAAT) was the most important predictor for the SOCS simulation.The minimal residual of the linear mixed models was achieved in the vegetation type-based model,whereas the maximal residual was fitted in the soil type-based model.About 95% of SOCS could be found in Argosols,Cambosols and Isohumosols.The largest SOCS was found in the croplands with vegetation of Triticum aestivum L.,Sorghum bicolor(L.) Moench,Glycine max(L.) Merr.,Zea mays L.and Setaria italica(L.) P.Beauv.
文摘MANDELBROT enunciated the uncertainty of the length of a coastline in his paper"How long is the coastline of Britain?"published in "Science" in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. According to the fractal theory and conditions of fractal research of coastline,the controls of faults and biologic function on the fractal character of coastline are preliminarily discussed on the basis of GIS in this paper . Finally,some significant conclusions are drawn:1)the faults control the basic trends of coastlines of two study areas;2)the fractal dimension of coastline of Taiwan is smaller than that of Changle-Lufeng,because the faults of Taiwan more intensely control the trend and fractal dimension of the coastline;3)the larger the fractal dimension of the faults or the major faults,the more the controlling effect of them on the trend and fractal dimension of coastline; 4)the larger fractal dimension of the coastline of Changle-Lufeng indicates that the biologic function intensely shapes the coastline. In a word,the controls of faults and biologic function on the fractal character of coastline are discussed with a case study of China in this paper,it can be seen that faults and biologic function both have influence over the trend and fractal dimension of coastline,the fractal mechanism of coastline of two study areas may be so.
文摘The complete mitochondrial cytochrome oxidase subunit Ⅱ (COⅡ) gene of Penaeinae shrimp Fenneropenaeus chinensis was cloned and sequenced. The gene is 688 bp in length and codes for 229 amino acids. It shows 83.2%, 87.0% and 83.8% sequence similarity to Marsupenaeus Japonicus, Penaeus monodon and Farfantepenaeus notialis, respectively. The A+T content of the whole gene and that at the third position of codons are 64.7% and 78.2%, respectively. The phylogenetic relationship between F. chinensis and three other species representing genera Farfanatepenaeus, Marsupenaeus and Penaeus was analyzed. Results showed that the genetic distances among the four taxa ranged from 0.144 0 to 0.200 5, exceeding those estimated with COⅠ and partial 16S rRNA gene sequences among Marsupenaeus, Litopenaeus and Melicertus, and being therefore larger than the value among subgenera. It has been suggested that the COⅡ gene has a faster evolutionary rate than that of the COⅠ gene and partial 16S rRNA gene and could be used for phylogenetic analysis at genus or species level. The results of the present study indicated that Farfantepenaeus, Fenneropenaeus, Marsupenaeus and Penaeus are at a higher phylogenetic level than subgenus, which supports the opinion of the elevation of phylogenetic status of the four subgenera to genus level.
文摘The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing a high efficient and low cost network multi-well data management architecture based on the General Logging Curve Theory and the Cif data format; 2, implementing efficient visit and transmission of multi-well data in C/S local network based on TCP/IP protocol; 3,ensuring the safety of multi-well data in store, visit and application based on Unix operating system security. By using CifNet system, the researcher in office or at home can visit curves of any borehole in any working area of any oilfield. The application foreground of CifNet system is also commented.