Characteristics of urban heat island （UHI） effect and its cause are investigated by using MODIS data in April 2004. Surface parameters from the MODIS data have surface temperature （ts） albedo（α）, and normalized...Characteristics of urban heat island （UHI） effect and its cause are investigated by using MODIS data in April 2004. Surface parameters from the MODIS data have surface temperature （ts） albedo（α）, and normalized difference vegetation index （NDVI）. Their heterogeneities over urban and rural area are analyzed based on land cover classification, and their relations are also presented in order to explain the UHI effect. The results show that there exists obvious the UHI effect. Ts over urban areas are by 10.83 % higher than those over rural area, and NDVI and α over urban area are by 62 % and 18.75 % less than those over rural area, respectively. Surface temperature has significantly negative correlation with NDVI and their correlation coefficient is -0.73. Correlation between NDVI and albedo is determined by the spectrum of light. Difference in vegetation cover is the primary cause of the UHI effect.展开更多
Breeding practice for Undaria pinnatifida （Harvey） Suringar requires the screening of a large number of offspring from gametophyte crossings to obtain an elite variety for large-scale cultivation. To better understa...Breeding practice for Undaria pinnatifida （Harvey） Suringar requires the screening of a large number of offspring from gametophyte crossings to obtain an elite variety for large-scale cultivation. To better understand the genetic relationships of different gametophyte cultures isolated from different sources, 20 microsatellite loci were screened and 53 gametophyte clone cultures analyzed for U. pinnatijqda isolated from wild sporophytes in Vladivostok, Russia and from cultivated sporophytes from Dalian and Qingdao, China. One locus was abandoned because of poor amplification. At the sex-linked locus of Up-AC-2AS, 3 alleles were detected in 25 female gametophyte clones, with sizes ranging from 307 to 316 bp. At other loci, 3 to 7 alleles were detected with an average of 4.5 alleles per locus. The average number of alleles at each locus was 1.3 and 3.7 for Russian and Chinese gametophyte clones, respectively. The average gene diversity for Russian, Chinese, and for the combined total of gametophyte clones was 0.1, 0.4, and 0.5, respectively. Russian gametophyte clones had unique alleles at 7 out of the 19 loci. In cluster analysis, Russian and Chinese gametophyte clones were separated into two different groups according to genetic distance. Overall, high genetic diversity was detected in gametophyte clones isolated from the two countries. These gametophyte cultures were believed to be appropriate parental materials for conducting breeding programs in the future.展开更多
The spatial structure and variation of the upwelling in the waters east and northeast of Hainan Island, China during 2000-2007 were investigated using a nested high-resolution Princeton Ocean Model (POM) forced by Qui...The spatial structure and variation of the upwelling in the waters east and northeast of Hainan Island, China during 2000-2007 were investigated using a nested high-resolution Princeton Ocean Model (POM) forced by QuikSCAT winds. The model produced good simulations of the summer upwelling and the seasonal and annual variability. Strong upwelling occurs from mid-July to mid-August with a peak east of Hainan Island associated with the southwesterly monsoon in the South China Sea. Sensitivity experiments indicated that when the local wind stress controls the variability of the upwelling, the large-scale circulation significantly enhances the upwelling northeast of Hainan Island by inducing a local upwelling and transporting cold water northeast-ward along the island's east coast. The joint effects of the local wind stress and large-scale circulation result in stronger upwelling northeast of Hainan Island. This implies that the annual variation of the upwelling northeast of Hainan Island is controlled not only by the local alongshore wind stress but also by the large-scale circulation. This result will help us investigate the decadal variation of the upwelling in this region in the future.展开更多
Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land ...Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land cover and normalized difference vegetation index (NDVI) were discussed. The result of LST showed that the urban LST was evidently higher than the suburban one. The average urban LST was found to 4.5 ℃ and 9 ℃ higher than the suburban and outer suburban temperature, respectively, which demonstrated the prominent UHI effects in Beijing. Prominent negative correlation between LST and NDVI was found in the urban area, which suggested the low percent vegetation cover in the urban area was the main cause of the urban heat island.展开更多
Banana bunchy top virus (BBTV),family Nanaviridae,genus Babuvirus,is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants.It is the most common and most destructive of all ...Banana bunchy top virus (BBTV),family Nanaviridae,genus Babuvirus,is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants.It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region.In this study we isolated,cloned and sequenced a BBTV sample from Hainan Island,China.The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs.We also predicted the physical and chemical properties,structure,signal peptide,phosphorylation,secondary structure,tertiary structure and functional domains of its encoding protein,and compare them with the corresponding quantities in the replication initiation protein of BBTV DNA1.展开更多
Coral reefs in the Xisha Islands （also known as the Paracel Islands in English）, South China Sea, have experienced dramatic declines in coral cover. However, the current regional scale hard coral distribution of geo...Coral reefs in the Xisha Islands （also known as the Paracel Islands in English）, South China Sea, have experienced dramatic declines in coral cover. However, the current regional scale hard coral distribution of geomorphic and ecological zones, essential for reefs management in the context of global warming and ocean acidification, is not well documented. We analyzed data from field surveys, Landsat-8 and GF-1 images to map the distribution of hard coral within geomorphic zones and reef fiat ecological zones. In situ surveys conducted in June 2014 on nine reefs provided a complete picture of reef status with regard to live coral diversity, evenness of coral cover and reef health （live versus dead cover） for the Xisha Islands. Mean coral cover was 12.5% in 2014 and damaged reefs seemed to show signs of recovery. Coral cover in sheltered habitats such as lagoon patch reefs and biotic dense zones of reef flats was higher, but there were large regional differences and low diversity. In contrast, the more exposed reef slopes had high coral diversity, along with high and more equal distributions of coral cover. Mean hard coral cover of other zones was 〈10%. The total Xisha reef system was estimated to cover 1 060 km2, and the emergent reefs covered -787 km2. Hard corals of emergent reefs were considered to cover 97 km2. The biotic dense zone of the reef flat was a very common zone on all simple atolls, especially the broader northern reef flats. The total cover of live and dead coral can reach above 70% in this zone, showing an equilibrium between live and dead coral as opposed to coral and algae. This information regarding the spatial distribution of hard coral can support and inform the management of Xisha reef ecosystems.展开更多
Petermann Glacier is a marine-terminating outlet glacier that had a 70 km-long floating ice tongue prior to a ～ 270 km2 calving event that was observed from satellite sensors in August 2010,shortening the ice tongue ...Petermann Glacier is a marine-terminating outlet glacier that had a 70 km-long floating ice tongue prior to a ～ 270 km2 calving event that was observed from satellite sensors in August 2010,shortening the ice tongue by ～ 27 km.Further,in July 2012,another 10 km was lost through calving.In order to understand these events in perspective,here the authors perform a long-term data analysis of Petermann Glacier calving-front variability and ice velocity for each year in the 1990s-2000s,supplemented by available observations from the previous three decades.Five major （on the order of 100 krm2） calving events are identified,with ～ 153 km2 calved from 1959 to 1961,～ 168 km2 in 1991,～ 71 km2 in 2001,～ 270 km2 in 2010,and ～ 130 km2 in 2012-as well as ～ 31 k m2 calved in 2008.The increased frequency of major calving events in recent years has left the front terminus position retreated nearly 25 km beyond the range of observed in previous decades.In contrast,stable ice-dynamics are suggested from ice-velocity measurements made each year between 1993-2012,which are on average 1063 m yr-1,with limited interannual variability and no significant trend; moreover,there is no apparent relationship between ice-velocity variability and calving events.The degree to which the massive calving events in 2010 and 2012 represent natural episodic variability or a response to atmospheric and/or oceanic changes remains speculative; however,melt-induced weakening of the floating ice tongue in recent years is strongly suggested.展开更多
An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the au...An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the austral summers 1997～1998 and 1999～2000,with the current coastline from a SPOT satellite image mosaic,topographic information from existing maps and from the Antarctic Digital Database.From this data sets,a digital terrain model (DTM) was generated using Arc/Info GIS.In a second step,a satellite image map at the scale 1∶100 000 was assembled from contour lines derived from the DTM and the satellite mosaic.A lack of accurate topographic information in the eastern part of the island was identified.Additional topographic surveying or SAR interferometry should be used to improve the data quality in that area.The GIS integrated database will be indispensable for glaciological and climatological studies and administrative and scientific purposes.In future,the application of GIS techniques will be mandatory for environmental impact studies and environmental monitoring as well as for management plans on King George Island.展开更多
Colorectal cancer(CRC)is a heterogeneous disease,arising from many possible etiological pathways.This heterogeneity can have important implications for CRC prognosis and clinical management.Epidemiological studies of ...Colorectal cancer(CRC)is a heterogeneous disease,arising from many possible etiological pathways.This heterogeneity can have important implications for CRC prognosis and clinical management.Epidemiological studies of CRC risk and prognosis—as well as clinical trials for the treatment of CRC—must therefore be sensitive to the molecular phenotype of colorectal tumors in patients under study.In this review,we describe four tumor markers that have been widely studied as reflections of CRC heterogeneity:(i)microsatellite instability(MSI)or DNA mismatch repair(MMR)deficiency,(ii)the CpG island methylator phenotype(CIMP),and somatic mutations in(iii)BRAF and(iv)KRAS.These tumor markers have been used to better characterize CRC epidemiology and,increasingly,may be used to guide clinical decision-making.Going beyond these traditional tumor markers,we also briefly review some more novel markers likely to be of clinical significance.Lastly,recognizing that none of these individual tumor markers are isolated attributes but,rather,a reflection of broader tumor phenotypes,we review some of the hypothesized etiological pathways of CRC development and their associated clinical differences.展开更多
基金the project of National Natural Science Funding of China under grant No.40075004.
文摘Characteristics of urban heat island （UHI） effect and its cause are investigated by using MODIS data in April 2004. Surface parameters from the MODIS data have surface temperature （ts） albedo（α）, and normalized difference vegetation index （NDVI）. Their heterogeneities over urban and rural area are analyzed based on land cover classification, and their relations are also presented in order to explain the UHI effect. The results show that there exists obvious the UHI effect. Ts over urban areas are by 10.83 % higher than those over rural area, and NDVI and α over urban area are by 62 % and 18.75 % less than those over rural area, respectively. Surface temperature has significantly negative correlation with NDVI and their correlation coefficient is -0.73. Correlation between NDVI and albedo is determined by the spectrum of light. Difference in vegetation cover is the primary cause of the UHI effect.
基金Supported by the National Special Research Fund for Non-Profit Sector(Agriculture)(No.200903030)the Agriculture Science Technology Achievement Transformation Fund(No.2010GB24910699)the Knowledge Innovation Programs of Chinese Academy of Sciences(No.KSCX2-EW-B-3)
文摘Breeding practice for Undaria pinnatifida （Harvey） Suringar requires the screening of a large number of offspring from gametophyte crossings to obtain an elite variety for large-scale cultivation. To better understand the genetic relationships of different gametophyte cultures isolated from different sources, 20 microsatellite loci were screened and 53 gametophyte clone cultures analyzed for U. pinnatijqda isolated from wild sporophytes in Vladivostok, Russia and from cultivated sporophytes from Dalian and Qingdao, China. One locus was abandoned because of poor amplification. At the sex-linked locus of Up-AC-2AS, 3 alleles were detected in 25 female gametophyte clones, with sizes ranging from 307 to 316 bp. At other loci, 3 to 7 alleles were detected with an average of 4.5 alleles per locus. The average number of alleles at each locus was 1.3 and 3.7 for Russian and Chinese gametophyte clones, respectively. The average gene diversity for Russian, Chinese, and for the combined total of gametophyte clones was 0.1, 0.4, and 0.5, respectively. Russian gametophyte clones had unique alleles at 7 out of the 19 loci. In cluster analysis, Russian and Chinese gametophyte clones were separated into two different groups according to genetic distance. Overall, high genetic diversity was detected in gametophyte clones isolated from the two countries. These gametophyte cultures were believed to be appropriate parental materials for conducting breeding programs in the future.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences (Nos. KZCX2-YW-Q11-02, KZCX2-EW-208)the One Hundred Talent Program of Chinese Academy of Sciences+1 种基金the National Natural Science Foundation of China (No. 41076009)the Youth Frontier Science Project of the South China Sea Institute of Oceanology(No. SQ200914)
文摘The spatial structure and variation of the upwelling in the waters east and northeast of Hainan Island, China during 2000-2007 were investigated using a nested high-resolution Princeton Ocean Model (POM) forced by QuikSCAT winds. The model produced good simulations of the summer upwelling and the seasonal and annual variability. Strong upwelling occurs from mid-July to mid-August with a peak east of Hainan Island associated with the southwesterly monsoon in the South China Sea. Sensitivity experiments indicated that when the local wind stress controls the variability of the upwelling, the large-scale circulation significantly enhances the upwelling northeast of Hainan Island by inducing a local upwelling and transporting cold water northeast-ward along the island's east coast. The joint effects of the local wind stress and large-scale circulation result in stronger upwelling northeast of Hainan Island. This implies that the annual variation of the upwelling northeast of Hainan Island is controlled not only by the local alongshore wind stress but also by the large-scale circulation. This result will help us investigate the decadal variation of the upwelling in this region in the future.
文摘Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land cover and normalized difference vegetation index (NDVI) were discussed. The result of LST showed that the urban LST was evidently higher than the suburban one. The average urban LST was found to 4.5 ℃ and 9 ℃ higher than the suburban and outer suburban temperature, respectively, which demonstrated the prominent UHI effects in Beijing. Prominent negative correlation between LST and NDVI was found in the urban area, which suggested the low percent vegetation cover in the urban area was the main cause of the urban heat island.
基金The Central Level,Scientific Research Institutes for Basic R & D Special Fund Business(ITBB110303)
文摘Banana bunchy top virus (BBTV),family Nanaviridae,genus Babuvirus,is a single stranded DNA virus (ssDNA) that causes banana bunchy top disease (BBTD) in banana plants.It is the most common and most destructive of all viruses in these plants and is widespread throughout the Asia-Pacific region.In this study we isolated,cloned and sequenced a BBTV sample from Hainan Island,China.The results from sequencing and bioinformatics analysis indicate this isolate represents a satellite DNA component with 12 DNA sequences motifs.We also predicted the physical and chemical properties,structure,signal peptide,phosphorylation,secondary structure,tertiary structure and functional domains of its encoding protein,and compare them with the corresponding quantities in the replication initiation protein of BBTV DNA1.
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA12A406)the National Natural Science Foundation of China(No.41271409)the National Science and Technology Major Project(No.00-Y30B15-9001-14/16-5)
文摘Coral reefs in the Xisha Islands （also known as the Paracel Islands in English）, South China Sea, have experienced dramatic declines in coral cover. However, the current regional scale hard coral distribution of geomorphic and ecological zones, essential for reefs management in the context of global warming and ocean acidification, is not well documented. We analyzed data from field surveys, Landsat-8 and GF-1 images to map the distribution of hard coral within geomorphic zones and reef fiat ecological zones. In situ surveys conducted in June 2014 on nine reefs provided a complete picture of reef status with regard to live coral diversity, evenness of coral cover and reef health （live versus dead cover） for the Xisha Islands. Mean coral cover was 12.5% in 2014 and damaged reefs seemed to show signs of recovery. Coral cover in sheltered habitats such as lagoon patch reefs and biotic dense zones of reef flats was higher, but there were large regional differences and low diversity. In contrast, the more exposed reef slopes had high coral diversity, along with high and more equal distributions of coral cover. Mean hard coral cover of other zones was 〈10%. The total Xisha reef system was estimated to cover 1 060 km2, and the emergent reefs covered -787 km2. Hard corals of emergent reefs were considered to cover 97 km2. The biotic dense zone of the reef flat was a very common zone on all simple atolls, especially the broader northern reef flats. The total cover of live and dead coral can reach above 70% in this zone, showing an equilibrium between live and dead coral as opposed to coral and algae. This information regarding the spatial distribution of hard coral can support and inform the management of Xisha reef ecosystems.
基金supported by the Trond Mohn Donation to the Mohn-Sverdrup Center at the Nansen Center,the Research Council of Norway’s UK/Netherlands/Norway RAPID programthe project AWAKE under the Polish-Norwegian Research Fund(2009–2011)
文摘Petermann Glacier is a marine-terminating outlet glacier that had a 70 km-long floating ice tongue prior to a ～ 270 km2 calving event that was observed from satellite sensors in August 2010,shortening the ice tongue by ～ 27 km.Further,in July 2012,another 10 km was lost through calving.In order to understand these events in perspective,here the authors perform a long-term data analysis of Petermann Glacier calving-front variability and ice velocity for each year in the 1990s-2000s,supplemented by available observations from the previous three decades.Five major （on the order of 100 krm2） calving events are identified,with ～ 153 km2 calved from 1959 to 1961,～ 168 km2 in 1991,～ 71 km2 in 2001,～ 270 km2 in 2010,and ～ 130 km2 in 2012-as well as ～ 31 k m2 calved in 2008.The increased frequency of major calving events in recent years has left the front terminus position retreated nearly 25 km beyond the range of observed in previous decades.In contrast,stable ice-dynamics are suggested from ice-velocity measurements made each year between 1993-2012,which are on average 1063 m yr-1,with limited interannual variability and no significant trend; moreover,there is no apparent relationship between ice-velocity variability and calving events.The degree to which the massive calving events in 2010 and 2012 represent natural episodic variability or a response to atmospheric and/or oceanic changes remains speculative; however,melt-induced weakening of the floating ice tongue in recent years is strongly suggested.
文摘An improved topographic database for King George Island,one of the most frequently visited regions in Antarctica,is presented.A first step consisted in combining data from differential GPS surveys gained during the austral summers 1997～1998 and 1999～2000,with the current coastline from a SPOT satellite image mosaic,topographic information from existing maps and from the Antarctic Digital Database.From this data sets,a digital terrain model (DTM) was generated using Arc/Info GIS.In a second step,a satellite image map at the scale 1∶100 000 was assembled from contour lines derived from the DTM and the satellite mosaic.A lack of accurate topographic information in the eastern part of the island was identified.Additional topographic surveying or SAR interferometry should be used to improve the data quality in that area.The GIS integrated database will be indispensable for glaciological and climatological studies and administrative and scientific purposes.In future,the application of GIS techniques will be mandatory for environmental impact studies and environmental monitoring as well as for management plans on King George Island.
文摘Colorectal cancer(CRC)is a heterogeneous disease,arising from many possible etiological pathways.This heterogeneity can have important implications for CRC prognosis and clinical management.Epidemiological studies of CRC risk and prognosis—as well as clinical trials for the treatment of CRC—must therefore be sensitive to the molecular phenotype of colorectal tumors in patients under study.In this review,we describe four tumor markers that have been widely studied as reflections of CRC heterogeneity:(i)microsatellite instability(MSI)or DNA mismatch repair(MMR)deficiency,(ii)the CpG island methylator phenotype(CIMP),and somatic mutations in(iii)BRAF and(iv)KRAS.These tumor markers have been used to better characterize CRC epidemiology and,increasingly,may be used to guide clinical decision-making.Going beyond these traditional tumor markers,we also briefly review some more novel markers likely to be of clinical significance.Lastly,recognizing that none of these individual tumor markers are isolated attributes but,rather,a reflection of broader tumor phenotypes,we review some of the hypothesized etiological pathways of CRC development and their associated clinical differences.
