This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of a...This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of all, geometric correction and supervised classification were conducted for ten scenes of Landsat-5 TM or MSS images. The resolution of the processed images is 50 m ×50 m on ground. By the classification the land use/cover categories in this area were discriminated. Then the croplands including rice fields and upland fields were extracted from the land use/cover maps. Simultaneously the slope grade maps were prepared based on the topographic maps. Overlaying the slope grade maps and the cropland maps, the area and percentage of the croplands in different slope grades were determined. This case study indicated that 71.5% of the uplands was situated on the slope above 15° and 25% on the slope above 25° in this area. It is dangerous, and urgent cultivation or engineering measures should be taken. Another case study is on soil erosion in Linshan County of Guangxi Province. Airphoto interpretation and supervised classification of a Landsat TM image were carried out for discriminating land cover/use categories in an area of 3557.8 km2.And the soil erosion intensity grades were determined according to the land cover/use maps and slope maps.It wed discovered that the land suffering soil erosion accounted for 2404.0 km2, 67.6% of the total area of the county. Necessary measures to control soil erosion should be taken also.展开更多
This paper describes a new type of transformed Landsat images (LBV images) and their application in discriminating soil gleization in subtropic region of China. LBV transformation was worked out by the present author ...This paper describes a new type of transformed Landsat images (LBV images) and their application in discriminating soil gleization in subtropic region of China. LBV transformation was worked out by the present author for extracting useful information from original landsat images. Using this method three black and white images, L image, B image and V image, were computer generated from original bands of a Landsat scene, which covers a.large area of 34 528 km2 in Hubei and Hunan provinces in south China. Then a color composite was produced by these three images. This kind of black-and-white and color images contained rich and definite geographic information. By a field work, the relationship between the colors on the composite and the land use/cover categories on the ground was established. 37 composite colors and 70 ground feature categories can be discriminated altogether. Finally, 17 land use/cover categories and 10 subregions suffering from soil gleization were determined, and the gleization area for the study area was estimated to be 731.3 km2.展开更多
A novel subtype of influenza A virus 09H1N1 has rapidly spread across the world. Evolutionary analyses of this virus have revealed that 09H1N1 is a triple reassortant of segments from swine, avian and human influenza ...A novel subtype of influenza A virus 09H1N1 has rapidly spread across the world. Evolutionary analyses of this virus have revealed that 09H1N1 is a triple reassortant of segments from swine, avian and human influenza viruses. In this study, we investigated factors shaping the codon usage bias of 09H1N1 and carried out cluster analysis of 60 strains of influenza A virus from different subtypes based on their codon usage bias. We discovered that more preferentially used codons of 09H1N1 are A-ended or U-ended, and the intra-genomic codon usage bias of 09H1N1 is quite low. Base composition constraint, dinucleotide biases and translational selection are the main factors influencing the codon usage bias of 09H1N1. At the genome level, we find that the codon usage bias of 09H1N1 is similar to H1N1 (A/swine/Kansas/77778/2007H1N1), H9N2 from Asia, H1N2 from Asia and North America and H3N2 from North America. Our results provide insight for understanding the processes governing evolution, regulation of gene expression, and revealing the evolution of 09H1N1.展开更多
The journal Truth, Beauty, and Goodness was the main field where ZENG Xu-bai published his literature works; in response to the miscellaneous "revolutionary literature" at that time, he put forward the idea that lit...The journal Truth, Beauty, and Goodness was the main field where ZENG Xu-bai published his literature works; in response to the miscellaneous "revolutionary literature" at that time, he put forward the idea that literature should be a combination of unity and artistry, and emphasized self-expression of literature on the basis of popularization of literature. With these literature views, his works also had shown his pursuit for the specialty and artistry of literature, as well as a transition from technique-oriented writing to a balance of emotion expression and technique usage. Anyway, during his translation of French literature and creative practice, the rich literature nutrition he received led to his unclear and complex thoughts which he neutralized with carefulness, and hence his unique literature views.展开更多
Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that...Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that can be collected flexibly in a short time and at a relatively low price. Also, drones have an important role in filling the gaps of common data collected using manned aircraft or satellite remote sensing, while having many advantages both in research and in various practical applications particularly in forestry as well as in land use in general. This paper aims to briefly describe the different approaches of applications of UAVs (Unmanned Aircraft Vehicles) in forestry, such as forest mapping, forest management planning, canopy height model creation or mapping forest gaps. These approaches have great potential in the near future applications and their quick implementation in a variety of situations is desirable for the sustainable management of forests.展开更多
Hepatitis C virus (HCV) infects approximately 200 million people worldwide. Interferon-based therapies have dominated over the past two decades. However, the overall response rates remain suboptimal. Thanks to the tre...Hepatitis C virus (HCV) infects approximately 200 million people worldwide. Interferon-based therapies have dominated over the past two decades. However, the overall response rates remain suboptimal. Thanks to the tremendous effort from both academia and industry, two serine protease inhibitors telaprevir and boceprevir for treating chronic hepatitis C have finally reached the clinic. Although these compounds are only approved for combination use with interferon and ribavirin in genotype 1 HCV infected chronic patients, the management of HCV patients however is now evolving incredibly. Here, we overviewed a series of landmark studies, regarding the clinical development of telaprevir and boceprevir. We discussed the mechanism-of-action of telaprevir/boceprevir and their potential application in HCV-positive liver transplantation patients. We further emphasized some emerging concerns with perspective of further development in this field.展开更多
Application of a DFIG (doubly-fed induction generator), which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supp...Application of a DFIG (doubly-fed induction generator), which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supply is one of important roles for the gas engine eogeneration system. In the case of conventional constant speed of synchronous generator, the amount of the allowed step load is limited to around 30% of the rated power. On the other hand, DFIG is expected to increase the amount of step load during the stand-alone operation. In this paper, it has been demonstrated that an increase in the gas engine speed resulted in an increase in the maximum amount of step load using experimental equipment with a real gas engine. It has been concluded that the proposed system can improve the performance of an emergency power supply at step-loading.展开更多
Internet use has become an indispensable part of people’s daily lives,and the relationship between Internet use and residents’subjective well-being is receiving increasing attention from researchers.However,the exis...Internet use has become an indispensable part of people’s daily lives,and the relationship between Internet use and residents’subjective well-being is receiving increasing attention from researchers.However,the existing literature on the relationship between Internet use and residents’subjective well-being is still controversial and inconclusive,and there has been relatively little discussion of the mechanisms by which Internet use affects well-being.On the basis of data from the China General Social Survey 2015(CGSS2015),this paper provides an empirical analysis of the impact of Internet usage on residents’subjective wellbeing.The study finds that while Internet use had no significant impact on the well-being of residents compared to non-use,frequency of Internet usage did significantly improve subjective well-being.On this basis,we tested the mechanisms by which Internet use affects residents’well-being through the three channels of the personal income effect,the human capital effect and the social capital effect.The findings partially verify the hypothesis of the mediating effect of social capital between Internet use and residents’subjective wellbeing,but do not verify the hypothesis of the moderating effect of personal income and human capital.Compared with previous studies,this paper is innovative in the following three ways:it uses the latest available representative national microdata,which is better able to reflect recent Internet usage and its impact on residents’subjective well-being;on the basis of existing research on the impact of Internet usage on residents’well-being,it analyzes the specific mechanisms through which Internet use affects well-being,using the moderating effect model and the mediating effect model to make up for the shortcomings of existing research on the impact mechanism;and it applies the Bioprobit model to deal with the potential endogeneity of key explanatory variables,using a variety of model estimation methods to obtain more robust estimation results.展开更多
文摘This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of all, geometric correction and supervised classification were conducted for ten scenes of Landsat-5 TM or MSS images. The resolution of the processed images is 50 m ×50 m on ground. By the classification the land use/cover categories in this area were discriminated. Then the croplands including rice fields and upland fields were extracted from the land use/cover maps. Simultaneously the slope grade maps were prepared based on the topographic maps. Overlaying the slope grade maps and the cropland maps, the area and percentage of the croplands in different slope grades were determined. This case study indicated that 71.5% of the uplands was situated on the slope above 15° and 25% on the slope above 25° in this area. It is dangerous, and urgent cultivation or engineering measures should be taken. Another case study is on soil erosion in Linshan County of Guangxi Province. Airphoto interpretation and supervised classification of a Landsat TM image were carried out for discriminating land cover/use categories in an area of 3557.8 km2.And the soil erosion intensity grades were determined according to the land cover/use maps and slope maps.It wed discovered that the land suffering soil erosion accounted for 2404.0 km2, 67.6% of the total area of the county. Necessary measures to control soil erosion should be taken also.
文摘This paper describes a new type of transformed Landsat images (LBV images) and their application in discriminating soil gleization in subtropic region of China. LBV transformation was worked out by the present author for extracting useful information from original landsat images. Using this method three black and white images, L image, B image and V image, were computer generated from original bands of a Landsat scene, which covers a.large area of 34 528 km2 in Hubei and Hunan provinces in south China. Then a color composite was produced by these three images. This kind of black-and-white and color images contained rich and definite geographic information. By a field work, the relationship between the colors on the composite and the land use/cover categories on the ground was established. 37 composite colors and 70 ground feature categories can be discriminated altogether. Finally, 17 land use/cover categories and 10 subregions suffering from soil gleization were determined, and the gleization area for the study area was estimated to be 731.3 km2.
文摘A novel subtype of influenza A virus 09H1N1 has rapidly spread across the world. Evolutionary analyses of this virus have revealed that 09H1N1 is a triple reassortant of segments from swine, avian and human influenza viruses. In this study, we investigated factors shaping the codon usage bias of 09H1N1 and carried out cluster analysis of 60 strains of influenza A virus from different subtypes based on their codon usage bias. We discovered that more preferentially used codons of 09H1N1 are A-ended or U-ended, and the intra-genomic codon usage bias of 09H1N1 is quite low. Base composition constraint, dinucleotide biases and translational selection are the main factors influencing the codon usage bias of 09H1N1. At the genome level, we find that the codon usage bias of 09H1N1 is similar to H1N1 (A/swine/Kansas/77778/2007H1N1), H9N2 from Asia, H1N2 from Asia and North America and H3N2 from North America. Our results provide insight for understanding the processes governing evolution, regulation of gene expression, and revealing the evolution of 09H1N1.
文摘The journal Truth, Beauty, and Goodness was the main field where ZENG Xu-bai published his literature works; in response to the miscellaneous "revolutionary literature" at that time, he put forward the idea that literature should be a combination of unity and artistry, and emphasized self-expression of literature on the basis of popularization of literature. With these literature views, his works also had shown his pursuit for the specialty and artistry of literature, as well as a transition from technique-oriented writing to a balance of emotion expression and technique usage. Anyway, during his translation of French literature and creative practice, the rich literature nutrition he received led to his unclear and complex thoughts which he neutralized with carefulness, and hence his unique literature views.
文摘Recently, drones have found applicability in a variety of study fields, one of these being forestry, where an increasing interest is given to this segment of technology, especially due to the high-resolution data that can be collected flexibly in a short time and at a relatively low price. Also, drones have an important role in filling the gaps of common data collected using manned aircraft or satellite remote sensing, while having many advantages both in research and in various practical applications particularly in forestry as well as in land use in general. This paper aims to briefly describe the different approaches of applications of UAVs (Unmanned Aircraft Vehicles) in forestry, such as forest mapping, forest management planning, canopy height model creation or mapping forest gaps. These approaches have great potential in the near future applications and their quick implementation in a variety of situations is desirable for the sustainable management of forests.
基金Supported by Foundation for Liver and Gastrointestinal Research (SLO)The Netherlands Organisation for Scientific Research (NWO), No. VENI-grant 916-13-032 (to Pan Q)
文摘Hepatitis C virus (HCV) infects approximately 200 million people worldwide. Interferon-based therapies have dominated over the past two decades. However, the overall response rates remain suboptimal. Thanks to the tremendous effort from both academia and industry, two serine protease inhibitors telaprevir and boceprevir for treating chronic hepatitis C have finally reached the clinic. Although these compounds are only approved for combination use with interferon and ribavirin in genotype 1 HCV infected chronic patients, the management of HCV patients however is now evolving incredibly. Here, we overviewed a series of landmark studies, regarding the clinical development of telaprevir and boceprevir. We discussed the mechanism-of-action of telaprevir/boceprevir and their potential application in HCV-positive liver transplantation patients. We further emphasized some emerging concerns with perspective of further development in this field.
文摘Application of a DFIG (doubly-fed induction generator), which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supply is one of important roles for the gas engine eogeneration system. In the case of conventional constant speed of synchronous generator, the amount of the allowed step load is limited to around 30% of the rated power. On the other hand, DFIG is expected to increase the amount of step load during the stand-alone operation. In this paper, it has been demonstrated that an increase in the gas engine speed resulted in an increase in the maximum amount of step load using experimental equipment with a real gas engine. It has been concluded that the proposed system can improve the performance of an emergency power supply at step-loading.
文摘Internet use has become an indispensable part of people’s daily lives,and the relationship between Internet use and residents’subjective well-being is receiving increasing attention from researchers.However,the existing literature on the relationship between Internet use and residents’subjective well-being is still controversial and inconclusive,and there has been relatively little discussion of the mechanisms by which Internet use affects well-being.On the basis of data from the China General Social Survey 2015(CGSS2015),this paper provides an empirical analysis of the impact of Internet usage on residents’subjective wellbeing.The study finds that while Internet use had no significant impact on the well-being of residents compared to non-use,frequency of Internet usage did significantly improve subjective well-being.On this basis,we tested the mechanisms by which Internet use affects residents’well-being through the three channels of the personal income effect,the human capital effect and the social capital effect.The findings partially verify the hypothesis of the mediating effect of social capital between Internet use and residents’subjective wellbeing,but do not verify the hypothesis of the moderating effect of personal income and human capital.Compared with previous studies,this paper is innovative in the following three ways:it uses the latest available representative national microdata,which is better able to reflect recent Internet usage and its impact on residents’subjective well-being;on the basis of existing research on the impact of Internet usage on residents’well-being,it analyzes the specific mechanisms through which Internet use affects well-being,using the moderating effect model and the mediating effect model to make up for the shortcomings of existing research on the impact mechanism;and it applies the Bioprobit model to deal with the potential endogeneity of key explanatory variables,using a variety of model estimation methods to obtain more robust estimation results.