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Microsatellite Variation Within Three Populations of Inbred C57BL/6J Strain 被引量:2
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作者 牛屹东 梁蜀龙 《Zoological Research》 CAS CSCD 北大核心 2008年第6期599-602,共4页
The goal of this study was to investigate the genetic stability of the C57BL/6J (B6) inbred mouse strain maintained in different breeders. Three populations of B6, Popl and Pop2 purchased from Beijing and Pop3 purch... The goal of this study was to investigate the genetic stability of the C57BL/6J (B6) inbred mouse strain maintained in different breeders. Three populations of B6, Popl and Pop2 purchased from Beijing and Pop3 purchased from Shanghai, were examined. Fifteen microsatellite loci reported to be polymorphic among inbred strains were amplified using FAM labeled primers and genotyped with ABI Prism 377 automated sequencer. Seven loci were found polymorphic, and all the loci were homozygous in all the three populations. The present study indicates that genetic variation occurs in different B6 populations although they are still inbred in each breeder. The mechanism of genetic variation is not well understood now, but it is very important to know the precise content of the B6 genome before use of this strain in research. 展开更多
关键词 C57BL/6J strain Microsatellite locus Genetic variation
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Assessment of Genetic Variability and Inter-specific Relationships among Four Species of Groupers (Genus Epinephelus) from South China Sea Using Microsatellite Markers 被引量:2
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作者 尹绍武 黄海 +1 位作者 骆剑 胡亚丽 《Agricultural Science & Technology》 CAS 2012年第2期428-433,共6页
[Objective] The study aimed to evaluate the genetic variability and interspecific relationships among four species of groupers from South China Sea, including E. fario, E. merra, E. malabaricus and E. coioides. [Metho... [Objective] The study aimed to evaluate the genetic variability and interspecific relationships among four species of groupers from South China Sea, including E. fario, E. merra, E. malabaricus and E. coioides. [Method] Twenty one mircosatellite loci of groupers were selected from GenBank and eight high polymorphic loci were used to further genetic analysis. [Result] The mean number of alleles per locus (A), effective number of alleles (Ne), mean polymorphism information content (PIC), observed heterozygosity (Ho) and expected heterozygosity (He) were 4.38±1.60, 3.69±0.86, 0.69±0.08, 0.67±0.08, 0.72±0.06 in E. malabaricus; 3.88±1.13, 3.55±1.04, 0.66±0.10, 0.68±0.21, 0.70±0.08 in E.coioides; 6.00±1.07, 4.68±0.65, 0.78±0.03, 0.73±0.25, 0.79±0.03 in E. fario; 5.50±1.07, 4.58±0.80, 0.76±0.05, 0.75±0.18, 0.78±0.04 in E. merra, respectively. [Conclusion] We compared the values above, the order of the genetic variability among these grouper species was E. fario E. merra E. malabaricus E. coioides. We found that the level of genetic variability of these groupers species was relatively higher than that of other marine fish, so their genetic status was good. In addition, the analyisis of genetic relationship showed that E. malabaricus and E. coioides was the closest and it was the farthest between E. merra and E. coioides. 展开更多
关键词 GROUPER EPINEPHELUS Genetic variability Species relationships Microsatellite marker
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为什么星星的亮度会变化?
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作者 王鸣阳(翻译) 《科学世界》 2008年第2期71-71,共1页
仰望夜空,观赏那些在天穹上按照星座形状分布着的恒星,你大概觉得它们的亮度是不变的吧。但实际情况并非如此。在秋高气爽的夜晚,你可以在鲸鱼座看到一颗中文名称叫做“刍藁增二”的恒星(鲸鱼座O),它就是一颗亮度反复变化非常大... 仰望夜空,观赏那些在天穹上按照星座形状分布着的恒星,你大概觉得它们的亮度是不变的吧。但实际情况并非如此。在秋高气爽的夜晚,你可以在鲸鱼座看到一颗中文名称叫做“刍藁增二”的恒星(鲸鱼座O),它就是一颗亮度反复变化非常大的具有代表性的恒星。这种亮度不断变化的恒星,天文学上的术语叫做“变星”。 展开更多
关键词 亮度 中文名称 鲸鱼座 天文学 夜空 “变星”
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Combined Method of Datum Transformation Between Different Coordinate Systems 被引量:4
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2002年第4期5-9,共5页
The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy ... The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy to that with high accuracy cannot guarantee a high precision of transformation.In this paper,a combined method of similarity transformation and regressive approximating is presented.The local error accumulation and distortion are taken into consideration and the precision of coordinate system is improved by using the recommended method 展开更多
关键词 coordinate transformation similarity transformation regressive approximating
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Cultivated Land Changes and Their Driving Forces——A Satellite Remote Sensing Analysis in the Yellow River Delta,China 被引量:19
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作者 ZHAOGeng-Xing G.LIN +1 位作者 J.J.FLETCHER C.YUILL 《Pedosphere》 SCIE CAS CSCD 2004年第1期93-102,共10页
Taking Kenli County in the Yellow River Delta, China, as the study area and using digital satellite remote sensing techniques, cultivated land use changes and their corresponding driving forces were explored in this s... Taking Kenli County in the Yellow River Delta, China, as the study area and using digital satellite remote sensing techniques, cultivated land use changes and their corresponding driving forces were explored in this study. An interactive interpretation and a manual modification procedure were carried out to acquire cultivated land information. An overlay method based on classification results and a visual change detection method which was supported by land use maps were employed to detect the cultivated land changes. Based on the changes that were revealed and a spatial analysis between cultivated land use and related natural and socio-economic factors, the driving forces for cultivated land use changes in the study area were determined.The results showed a decrease in cultivated land in Kenli County of 5321.8 ha from 1987 to 1998, i.e.,an average annual decrement of 483.8 ha, which occurred mainly in the central paddy field region and the northeast dry land region. Adverse human activities, soil salinization and water deficiencies were the driving forces that caused these cultivated land use changes. 展开更多
关键词 cultivated land driving force satellite remote sensing the yellow riverdelta
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Eddy generation and evolution in the North Pacific Subtropical Countercurrent(NPSC) zone 被引量:7
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作者 康霖 王凡 陈永利 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期968-973,共6页
The seasonal generation and evolution of eddies in the region of the North Pacific Subtropical Countercurrent remain poorly understood due to the scarcity of available data.We used TOPEX/POSEIDON altimetry data from 1... The seasonal generation and evolution of eddies in the region of the North Pacific Subtropical Countercurrent remain poorly understood due to the scarcity of available data.We used TOPEX/POSEIDON altimetry data from 1992 to 2007 to study the eddy field in this zone.We found that velocity shear between this region and the neighboring North Equatorial Current contributes greatly to the eddy generation.Furthermore,the eddy kinetic energy level(EKE) shows an annual cycle,maximum in April/May and minimum in December/January.Analyses of the temporal and spatial distributions of the eddy field revealed clearly that the velocity shear closely related to baroclinic instability processes.The eddy field seems to be more zonal than meridional,and the energy containing length scale shows a surprising lag of 2-3 months in comparison with the 1-D and 2-D EKE level.A similar phenomenon is observed in individual eddies in this zone.The results show that in this eddy field band,the velocity shear may drive the EKE level change so that the eddy field takes another 2-3 months to grow and interact to reach a relatively stable state.This explains the seasonal evolution of identifiable eddies. 展开更多
关键词 TOPEX/POSEIDON altimetry eddy field EKE velocity shear North Pacific SubtropicalCountercurrent
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The Gene of Megalencephalic Leukoencephalopathy with Subcortical Cysts is Mapped on Chromosome 22q13.3 with 250 kb Interval
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作者 袁宝强 Peter AJ Leegwater +2 位作者 Andrea AM Konst Jan C Pronk Marjo S van der Knaap 《Journal of Nanjing Medical University》 2003年第4期173-182,共10页
Objective: Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a recently described syndrome with autosomal recessive mode of inheritance. Its possible gene was located on chromosomal 22q ... Objective: Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a recently described syndrome with autosomal recessive mode of inheritance. Its possible gene was located on chromosomal 22q tel with 3-cM. The purpose of this study was to narrow down the genetical distance on chromosomal 22q tel with MLC. Methods: Thirty-nine MLC patients in 33 families were collected,and the linkage analysis and haplotype analysis of twelve informative families were done, using seven microsatellite markers and four SNP markers. Results: The maximum tow-point LOD score for marker 355c18 was 6.65 at recombination fraction 0.02. The haplotype analysis narrowed down the critical region of MLC to 250 kb on chromosomal 22q tel. Conclusion: One of the causing genes of MLC was located on chromosomal 22q tel with 250 kb. Four candidate genes were considered. The heterogeneity of one informative family indicated possible existence of a second locus for MLC. 展开更多
关键词 vacuolating megalencephalic leukoencephalopathy with subcortical cysts autosomal recessive mode of inheritance chromosome 22 linkage analysis position cloning microsatellite marker single-nucleotide polymorphisms
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Genetic changes of p53,K-ras,and microsatellite instability in gallbladder carcinoma in high-incidence areas of Japan and Hungary 被引量:9
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作者 Masayuki Nagahashi Yoichi Ajioka +10 位作者 Istvan Lang Zoltan Szentirmay Miklos Kasler Hiroto Nakadaira Naoyuki Yokoyama Gen Watanabe Ken Nishikura Toshifumi Wakai Yoshio Shirai Katsuyoshi Hatakeyama Masaharu Yamamoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期70-75,共6页
AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary. METHODS: We examined 42 cases of gallbladder carcinom... AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary. METHODS: We examined 42 cases of gallbladder carcinoma: 22 Japanese and 20 Hungarian cases, p53 mutations at exons 5 to 8 and K-ras mutations at codon 12 were tested by direct sequencing. Microsatellite instability was determined from fluorescent dye-labeled PCR amplifications of flve-microsatellite markers (BAT-25, BAT-26, D2S123, DSS346, and D17S250). RESULTS: Mutations of p53 were detected in 11 of 22 Japanese cases and 6 of 18 Hungarian cases (11/22 vs 6/18, P = 0.348). Transition at CpG sites was found in none of 11 Japanese cases and 2 of 6 Hungarian cases; the difference was marginally significant (0/11 vs 2/6,P = 0.110). K-ras mutations were detected in only one of the Hungarian cases. Eight of 19 (42.1%) ]apanese cases were MSI-high (presence of novel peaks in more than one of the five loci analyzed), whereas only 1 of 15 (6.7%) Hungarian cases was MSI-high (P = 0.047). CONCLUSION: It appears that the p53 mutations and MSI differ in patients with gallbladder carcinoma between two distinct high-incidence areas. Geographic variation might exist in the process of gallbladder carcinogenesis. 展开更多
关键词 GALLBLADDER Gallbladder Neoplasms K-RAS Microsatellite instability P53
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Study on Red Tide Remote Sensing Monitoring in the Bohai Sea in 2014 被引量:5
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作者 ZHANG He ZHENG Xiao-shen 《Marine Science Bulletin》 CAS 2017年第1期37-51,共15页
Since 2000, red tides have been reported in the Bohai Sea every year, whichoften made coastal waters of the Bohai Sea suffering from red tides. Satellite remotesensing technology and the ocean color observation satell... Since 2000, red tides have been reported in the Bohai Sea every year, whichoften made coastal waters of the Bohai Sea suffering from red tides. Satellite remotesensing technology and the ocean color observation satellite images have beensuccessfully used to identify and observe the initiation, evolution, and dissipation of redtide. However, due to different water bodies, remote sensing data and modelingmethods, a specific model of red tide inversion should be established for the watercharacteristics of the Bohai Sea. In this paper, the correlation analysis between MODISspectral reflectivity data and measured concentration of chlorophyll a in the Bohai Seawas carried out. The expression (B10-B8) / (B13-B8) was chosen as the indicator of redtide inversion in the Bohai Sea, the correlation coefficient reached 0.7815, showingsignificant correlation results. It was found that the spatial and temporal distribution ofred tide in the Bohai Sea in 2014 was obvious. The main causes of the large-scale outbreak of red tide in the Bohai Sea are due to the poor water exchange caused by thesemi-enclosed geomorphology and the large amount of terrestrial matter input fromcoastal runoff. The river input is the main source of land-based pollution into the sea.Then, a red tide inversion model based on a modified red tide index was established byusing GOCI remote sensing data with less cloud coverage, and proven effective indelineating the red tide in turbid waters. The hourly RI images on 15, 26 and 28 May2014 showed consistent evolution, and the area of red tide in the Bohai Sea changedsignificantly during one day. Vertical migration of the dominant species of red tide algaemay be the main reason for the short-term changes in the surface expression. 展开更多
关键词 red tide Bohai Sea MODIS GOCI remote sensing diurnal variation
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Urban Land Use Change Detection Using Multisensor Satellite Images 被引量:5
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作者 DENG Jin-Song WANG Ke +1 位作者 LI Jun DENG Yan-Hua 《Pedosphere》 SCIE CAS CSCD 2009年第1期96-103,共8页
Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in develope... Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in developed urban area in the coastal regions; therefore, there is an urgent need to effectively detect and monitor the land use changes and provide accurate and timely information for planning and management. In this study a method combining principal component analysis (PCA) of multisensor satellite images from SPOT (systeme pour l'observation de la terre or earth observation satellite)-5 multispectral (XS) and Landsat-7 enhanced thematic mapper (ETM) panchromatic (PAN) data, and supervised classification was used to detect and analyze the dynamics of land use changes in the city proper of Hangzhou. The overall accuracy of the land use change detection was 90.67% and Kappa index was 0.89. The results indicated that there was a considerable land use change (10.03% of the total area) in the study area from 2001 to 2003, with three major types of land use conversions: from cropland into built-up land, construction site, and water area (fish pond). Changes from orchard land into built-up land were also detected. The method described in this study is feasible and useful for detecting rapid land use change in the urban area. 展开更多
关键词 change detection land use multisensor satellite image principal component analysis (PCA) urban area
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Steatosis recovery after treatment with a balanced sunflower or olive oil-based diet: Involvement of perisinusoidal stellate cells 被引量:1
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作者 Raquel Hernández Esther Martínez-Lara +6 位作者 Ana Cauelo Ma Luisa del Moral Santos Blanco Eva Siles Ana Jiménez Juan ngel Pedrosa Ma ngeles Peinado 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第47期7480-7485,共6页
AIM: To analyze the relationship between perisinusoidal stellate cell (PSC) activation and the dietary fat quantity and composition in the treatment of hepatic steatosis. METHODS: Using an experimental rat model o... AIM: To analyze the relationship between perisinusoidal stellate cell (PSC) activation and the dietary fat quantity and composition in the treatment of hepatic steatosis. METHODS: Using an experimental rat model of steatosis based on the intake of a hyperlipidic diet (14% fat as olive oil or sunflower oil, HL-O and HL-S, respectively), we analyzed the liver's capability of recovery after the treatment with a normal-lipidic diet (5% fat as olive oil or sunflower oil, NL-O and NL-S, respectively) by immunoo/tochemical and Western blot analysis of glial fibrillary acidic protein (GFAP) expression in PSCs, collagen quantification and serum aminotransferase determination. RESULTS: The fatty infiltration in the steatotic livers decreased after the treatment with both NL diets, indicating liver recovery. This decrease was accompanied with a lower collagen deposition and aminotransferase level as well as changes in the PSC population that increased the GFAP expression. The above-mentioned effects were more pronounced in animals fed on NL-O based diet. CONCLUSION: Treatment with a balanced diet enriched in olive oil contributes to the liver recovery from a steatotic process. The PSC phenotype is a marker of this hepatic-recovery model. 展开更多
关键词 PSCs GFAP STEATOSIS Collagen Hyperlipidic diet Liver recovery Olive oil
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Microsatellite DNA markers to assess population structure of red tailed barb Gonoproktopterus curmuca 被引量:1
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作者 Achamveettil GOPALAKRISHNAN Kochikkaran Kunjumohammed MUSAMMILU +4 位作者 Peringady Mohammed ABDUL MUNEER Kuldeep Kumar LAL Dhurendra KAPOOR Alphis Geethanand PONNIAH Vindhya MOHINDRA 《动物学报》 SCIE CAS CSCD 北大核心 2004年第4期686-690,共5页
本文检测了三种鲤科鱼的 1 6对微卫星引物在红尾中的适用性 ,其中 6对引物可以成功扩增 ,且 5个位点具有多态性。对采自两条不同河流的标本 ,通过检测这些多态微卫星位点的遗传变异情况 ,评估了它们在红尾种群结构分析的适合性。结果显... 本文检测了三种鲤科鱼的 1 6对微卫星引物在红尾中的适用性 ,其中 6对引物可以成功扩增 ,且 5个位点具有多态性。对采自两条不同河流的标本 ,通过检测这些多态微卫星位点的遗传变异情况 ,评估了它们在红尾种群结构分析的适合性。结果显示这 5个多态位点在上述两个样本中的平均表观杂合度分别是 0 2 93和0 4 71。 展开更多
关键词 Red tailed barb Gonoproktopterus curmuca MICROSATELLITE Genetic variation
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Spatio-temporal Variations in Plantation Forests'Disturbance and Recovery of Northern Guangdong Province Using Yearly Landsat Time Series Observations(1986-2015) 被引量:4
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作者 SHEN Wenjuan LI Mingshi WEI Anshi 《Chinese Geographical Science》 SCIE CSCD 2017年第4期600-613,共14页
Forest disturbance plays a vital role in modulating carbon storage,biodiversity and climate change.Yearly Landsat imagery from 1986 to 2015 of a typical plantation region in the northern Guangdong province of southern... Forest disturbance plays a vital role in modulating carbon storage,biodiversity and climate change.Yearly Landsat imagery from 1986 to 2015 of a typical plantation region in the northern Guangdong province of southern China was used as a case study.A Landsat time series stack(LTSS) was fed to the vegetation change tracker model(VCT) to map long-term changes in plantation forests' disturbance and recovery,followed by an intensive validation and a continuous 27-yr change analysis on disturbance locations,magnitudes and rates of plantations' disturbance and recovery.And the validation results of the disturbance year maps derived from five randomly identified sample plots with 25 km^2 located at the four corners and the center of the scene showed the majority of the spatial agreement measures ranged from 60% to 83%.A confusion matrix summary of the accuracy measures for all four validation sites in Fogang County showed that the disturbance year maps had an overall accuracy estimate of 71.70%.Forest disturbance rates' change trend was characterized by a decline first,followed by an increase,then giving way to a decline again.An undulated and gentle decreasing trend of disturbance rates from the highest value of 3.95% to the lowest value of 0.76% occurred between 1988 and 2001,disturbance rate of 4.51% in 1994 was a notable anomaly,while after 2001 there was a sharp ascending change,forest disturbance rate spiked in 2007(5.84%).After that,there was a significant decreasing trend up to the lowest value of 1.96% in 2011 and a slight ascending trend from 2011 to 2015(2.59%).Two obvious spikes in post-disturbance recovery rates occurred in 1995(0.26%) and 2008(0.41%).Overall,forest recovery rates were lower than forest disturbance rates.Moreover,forest disturbance and recovery detection based on VCT and the Landsat-based detections of trends in disturbance and recovery(LandT rendr) algorithms in Fogang County have been conducted,with LandT rendr finding mostly much more disturbance than VCT.Overall,disturbances and recoveries in northern Guangdong were triggered mostly by timber needs,policies and decisions of the local governments.This study highlights that a better understanding about plantations' changes would provide a critical foundation for local forest management decisions in the southern China. 展开更多
关键词 plantation Landsat dense time series remote sensing forest disturbance and recovery driving forces northern Guangdong
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EVALUATION OF POWER SPECTRAL DENSITY OF PASSIVE INTERMODULATION DISTORTION IN HIGH-POWER COMMUNICATION SATELLITE SYSTEMS 被引量:1
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作者 ZhangShiquan GeDebiao 《Journal of Electronics(China)》 2005年第2期181-184,共4页
In order to analyze the deleterious effects of Passive InterModulation (PIM) on high power communication satellite systems, the basic concept of PIM is introduced, and an equation for the power spectral density of the... In order to analyze the deleterious effects of Passive InterModulation (PIM) on high power communication satellite systems, the basic concept of PIM is introduced, and an equation for the power spectral density of the n-th order PIM distortion insuch systems is derived by applying flat signal-power spectrum assumption and Fourier transform method. It is indicated that PIM level generally decreases with order and the lowest frequency receive channel in the receive band is the channel of most affected by PIM interference. 展开更多
关键词 Passive InterModulation(PIM) Power spectral density Fourier transform Communication satellite
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On Urban Heat Island of Beijng Based on Landsat TM Data 被引量:1
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作者 JIANG Zhangyan CHEN Yunhao LI Jing 《Geo-Spatial Information Science》 2006年第4期293-297,共5页
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
关键词 land surface temperature Landsat TM radiative transfer equation urban heat island
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Global Distribution of Thermosteric Contribution to Sea Level Rising Trend 被引量:1
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作者 ZUO Juncheng DU Ling +1 位作者 ZHANG Jianli CHEN Meixiang 《Journal of Ocean University of China》 SCIE CAS 2010年第3期199-209,共11页
The sea level derived from TOPEX/Poseidon (T/P) altimetry data shows prominent long term trend and inter-annual variability. The global mean sea level rising rate during 1993-2003 was 2.9mm a^-1. The T/P sea level t... The sea level derived from TOPEX/Poseidon (T/P) altimetry data shows prominent long term trend and inter-annual variability. The global mean sea level rising rate during 1993-2003 was 2.9mm a^-1. The T/P sea level trend maps the geographical variability. In the Northern Hemisphere (15°-64°N), the sea level rise is very fast at the mid-latitude (20°-40°N) but much slower at the high-latitude, for example, only 0.5 mm a^-1 in the latitude band 40°-50°N. In the Southern Hemisphere, the sea level shows high rising rate both in mid-latitude and high-latitude areas, for example, 5.1 mm a^-1 in the band 40°- 50°S. The global thermosteric sea level (TSL) derived from Ishii temperature data was rising during 1993-2003 at a rate of 1.2 mm a^-1 and accounted for more than 40% of the global T/P sea level rise. The contributions of the TSL distribution are not spatially uniform; for instance, the percentage is 67% for the Northern Hemisphere and only 29% for the Southern Hemisphere (15°-64°S) and the maximum thermosteric contribution appears in the Pacific Ocean, which contributes more than 60% of the global TSL. The sea level change trend in tropical ocean is mainly caused by the thermosteric effect, which is different from the case of seasonal variability in this area. The TSL variability dominates the T/P sea level rise in the North Atlantic, but it is small in other areas, and shows negative trend at the high-latitude area (40°-60°N, and 50°-60°S). The global TSL during 1945-2003 showed obvious rising trend with the rate of about 0.3 mm a-l and striking inter-annual and decadal variability with period of 20 years. In the past 60 years, the Atlantic TSL was rising continuously and remarkably, contributing 38% to the global TSL rising. The TSL in the Pacific and Indian Ocean rose with significant in- ter-annual and decadal variability. The first EOF mode of the global TSL from Ishii temperature data was the ENSO mode in which the time series of the first mode showed steady rising trend. Among the three oceans, the first mode of the Pacific TSL presented the ENSO mode; there was relatively steady rising trend in the Atlantic Ocean, and no dominant mode in the Indian Ocean. 展开更多
关键词 thermosteric effect sea level trend T/P altimeter spatial distribution
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High precision slope deformation monitoring model based on the GPS/Pseudolites technology in open-pit mine 被引量:26
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作者 WANG Jianpeng, GAO Jingxiang, LIU Chao, WANG Jian School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221008, China 《Mining Science and Technology》 EI CAS 2010年第1期126-131,137,共7页
As the number and geometric intensity of visual satellites are susceptible to large slopes in open-pit mines, we propose integration of GPS/Pseudolites (PLs) positioning technology which can increase the number of vis... As the number and geometric intensity of visual satellites are susceptible to large slopes in open-pit mines, we propose integration of GPS/Pseudolites (PLs) positioning technology which can increase the number of visible satellites, strengthen the geometric intensity of satellites and provide a precision solution for slope deformation monitoring. However, the un-modeled systematic errors are still the main limiting factors for high precision baseline solution. In order to eliminate the un-modeled systematic error, the Empirical Mode Decomposition (EMD) theory is employed. The multi-scale decomposition and reconstruction architecture are defined here on the basis of the EMD theory and the systematic error mitigation model is demonstrated as well. A standard of the scale selection for the systematic error elimination is given in terms of the mean of the accumulated standardized modes. Thereafter, the scheme of the GPS/PLs baseline solution based on the EMD is suggested. The simulation and experiment results show that the precision factors (DOP) are reduced greatly when PLs is located suitably. The proposed scheme dramatically improves the reliability of ambiguity resolution and the precision of baseline vector after systematic error being eliminated, and provides an effective model for high precision slope deformation monitoring in open-pit mine. 展开更多
关键词 open-pit mine slope deformation PLS EMD
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Alterations in the human epidermal growth factor receptor 2-phosphatidylinositol 3-kinase-v-Akt pathway in gastric cancer 被引量:20
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作者 Yasutaka Sukawa Hiroyuki Yamamoto +12 位作者 Katsuhiko Nosho Hiroaki Kunimoto Hiromu Suzuki Yasushi Adachi Mayumi Nakazawa Takayuki Nobuoka Mariko Kawayama Masashi Mikami Takashi Matsuno Tadashi Hasegawa Koichi Hirata Kohzoh Imai Yasuhisa Shinomura 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第45期6577-6586,共10页
AIM:To investigate human epidermal growth factor receptor 2(HER2)-phosphatidylinositol 3-kinase(PI3K)-vAkt murine thymoma viral oncogene homolog signaling pathway.METHODS:We analyzed 231 formalin-fixed,paraffinembedde... AIM:To investigate human epidermal growth factor receptor 2(HER2)-phosphatidylinositol 3-kinase(PI3K)-vAkt murine thymoma viral oncogene homolog signaling pathway.METHODS:We analyzed 231 formalin-fixed,paraffinembedded gastric cancer tissue specimens from Japanese patients who had undergone surgical treatment.The patients' age,sex,tumor location,depth of invasion,pathological type,lymph node metastasis,and pathological stage were determined by a review of the medical records.Expression of HER2 was analyzed by immunohistochemistry(IHC) using the HercepTest TM kit.Standard criteria for HER2 positivity(0,1+,2+,and 3+) were used.Tumors that scored 3+ were considered HER2-positive.Expression of phospho Akt(pAkt) was also analyzed by IHC.Tumors were considered pAkt-positive when the percentage of positive tumor cells was 10% or more.PI3K,catalytic,alpha polypeptide(PIK3CA) mutations in exons 1,9 and 20 were analyzed by pyrosequencing.Epstein-Barr virus(EBV) infection was analyzed by in situ hybridization targeting EBV-encoded small RNA(EBER) with an EBER-RNA probe.Microsatellite instability(MSI) was analyzed by polymerase chain reaction using the mononucleotide markers BAT25 and BAT26.RESULTS:HER2 expression levels of 0,1+,2+ and 3+ were found in 167(72%),32(14%),12(5%) and 20(8.7%) samples,respectively.HER2 overexpression(IHC 3+) significantly correlated with intestinal histological type(15/20 vs 98 /205,P = 0.05).PIK3CA mutations were present in 20 cases(8.7%) and significantly correlated with MSI(10/20 vs 9/211,P < 0.01).The mutation frequency was high(21%) in T4 cancers and very low(6%) in T2 cancers.Mutations in exons 1,9 and 20 were detected in 5(2%),9(4%) and 7(3%) cases,respectively.Two new types of PIK3CA mutation,R88Q and R108H,were found in exon1.All PIK3CA mutations were heterozygous missense singlebase substitutions,the most common being H1047R(6/20,30%) in exon20.Eighteen cancers(8%) were EBV-positive and this positivity significantly correlated with a diffuse histological type(13/18 vs 93/198,P = 0.04).There were 7 cases of lymphoepithelioma-like carcinomas(LELC) and 6 of those cases were EBV-positive(percent/EBV:6/18,33%;percent/all LELC:6/7,86%).pAkt expression was positive in 119(53%) cases but showed no correlation with clinicopathological characteristics.pAkt expression was significantly correlated with HER2 overexpression(16/20 vs 103/211,P < 0.01) but not with PIK3CA mutations(12/20 vs 107/211,P = 0.37) or EBV infection(8/18 vs 103/211,P = 0.69).The frequency of pAkt expression was higher in cancers with exon20 mutations(100%) than in those with exon1(40%) or exon9(56%) mutations.One case showed both HER2 overexpression and EBV infection and 3 cases showed both PIK3CA mutations and EBV infection.However,no cases showed both PIK3CA mutations and HER2 overexpression.One EBVpositive cancer with PIK3CA mutation(H1047R) was MSI-positive.Three of these 4 cases were positive for pAkt expression.In survival analysis,pAkt expression significantly correlated with a poor prognosis(hazard ratio 1.75;95%CI:1.12-2.80,P = 0.02).CONCLUSION:HER2 expression,PIK3CA mutations and EBV infection in gastric cancer were characterized.pAkt expression significantly correlates with HER2 expression and with a poor prognosis. 展开更多
关键词 Human epidermal growth factor receptor 2 Phosphatidylinositol 3-kinase CATALYTIC Alpha polypep-tide Epstein-Barr virus Aid: Gastric cancer
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Deconfinement Phase Transition Including Perturbative QCD Corrections in (Proto)neutron Star Matter
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作者 GU Jian-Fa GUO Hua +2 位作者 LEE Xi-Guo LIU Yu-Xin XU Fu-Rong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期461-466,共6页
Deconlinement phase transition and neutrino trapping in (proto)neutron star matter are investigated in a chiral hadronic model (also referred to as the FST model) for the hadronic phase (HP) and in the color-fla... Deconlinement phase transition and neutrino trapping in (proto)neutron star matter are investigated in a chiral hadronic model (also referred to as the FST model) for the hadronic phase (HP) and in the color-flavor-locked (CFL) quark model for the deconlined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K^0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the liP is dominant in the high-density region of (proto)neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter as or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of (proto)neutron stars are not sensitive to the QCD correction parameter αs. 展开更多
关键词 deconfinement phase transition neutrino trapping neutron star matter
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Using multispectral landsat and sentinel-2 satellite data to investigate vegetation change at Mount St. Helens since the great volcanic eruption in 1980 被引量:2
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作者 Katharina TELTSCHER Fabian Ewald FASSNACHT 《Journal of Mountain Science》 SCIE CSCD 2018年第9期1851-1867,共17页
Long-term analyses of vegetation succession after catastrophic events are of high interest for an improved understanding of succession dynamics. However, in many studies such analyses were restricted to plot-based mea... Long-term analyses of vegetation succession after catastrophic events are of high interest for an improved understanding of succession dynamics. However, in many studies such analyses were restricted to plot-based measurements. Contrarily, spatially continuous observations of succession dynamics over extended areas and timeperiods are sparse. Here, we applied a change vector analysis(CVA) to investigate vegetation succession dynamics at Mount St. Helens after the great volcanic eruption in 1980 using Landsat. We additionally applied a supervised random forest classification using Sentinel-2 data to map the currently prevailing vegetation types. Change vector analysis was performed with the normalized difference vegetation index(NDVI) and the urban index(UI) for three subsequent decades after the eruption as well as for the whole observation time between 1984 and 2016. The influence of topography on the current vegetation distribution was examined by comparing altitude, slope angles and aspect values of vegetation classes derived by the random forest classification. WilcoxRank-Sum test was applied to test for significant differences between topographic properties of the vegetation classes inside and outside of the areas affected by the eruption. For the full time period, a total area of 516 km2 was identified as re-vegetated, whereas the area and magnitude of re-growing vegetation decreased during the three decades and migrated closer to the volcanic crater. Vegetation losses were mainly observed in regions unaffected by the eruption and related mostly to timber harvesting. The vegetation type classification reached a high overall accuracy of approximately 90%. 36 years after the eruption, coniferous and deciduous trees have established at formerly devastated areas dominating with a proportion of 66%, whereas shrubs are more abundant in riparian zones. Sparse vegetation dominates at regions very close to the crater. Elevation was found to have a great influence on the reestablishment and distribution of the vegetation classes within the devastated areas showing in almost all cases significant differences in altitude distribution. Slope was less important for the different classes-only representing significantly higher values for meadows, whereas aspect seems to have no notable influence on the reestablishment of vegetation at Mount St. Helens. We conclude that major vegetation succession dynamics after catastrophic events can be assessed and characterized over large areas from freely available remote sensing data and hence contribute to an improved understanding of succession dynamics. 展开更多
关键词 Mount St. Helens Vegetation change Remote sensing Change vector analysis (CVA) Supervised classification Topography Density-plots
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