The change of impervious surface area(ISA) can effectively reveal the gradual process of urbanization and act as a key index for monitoring urban expansion. Experiencing rapid growth of the built environment in the 20...The change of impervious surface area(ISA) can effectively reveal the gradual process of urbanization and act as a key index for monitoring urban expansion. Experiencing rapid growth of the built environment in the 2000 s, urban expansion of Beijing has not been fully characterized through ISA. In this study, Landsat TM images of Beijing in 2001 and 2009 were obtained, and the eight-year urban expansion process in Beijing was analyzed using the ISA extracted by means of the vegetation-imperious surface-soil(V-I-S) model. From the spatial variation in ISA, the ring structure of urban expansion in Beijing was significant during the study period, with decreasing urban density from the city center to the periphery. In the ring road analysis, the most dramatic changes of ISA were found between the fifth ring and the sixth ring. This area has experienced the most new residential development, and is currently the main source of urban expansion. The typical profile lines revealed the directional characteristics of urban expansion. The east-west profile was the most urbanized axes in Beijing, while ISA change in the east-north profile was more significant than in the other five profiles. Moreover, the transition matrix of ISA levels revealed an increase in urban density in the low density built areas; the Moran′s I index showed a clear expansion of the central urban area, which spread contiguously; and the standard deviational ellipse indicated the northeast was the dominant direction of urban expansion. These findings can provide important spatial control guidelines in the next round of national economic and social development planning, overall urban and rural planning, and land use planning.展开更多
Measuring the internal velocity of debris flows is very important for debris flow dynamics research and designing debris flow control works. However, there is no appropriate method for measuring the internal velocity ...Measuring the internal velocity of debris flows is very important for debris flow dynamics research and designing debris flow control works. However, there is no appropriate method for measuring the internal velocity because of the destructive power of debris flow process. In this paper, we address this problem by using the relationship between velocity and kinetic pressure, as described by surface velocity and surface kinetic pressure data. Kinetic pressure is the difference of impact pressure and static pressure. The former is detected by force sensors installed in the flow direction at the sampling section. Observations show that static pressure can be computed using the formula for static water pressure by simply substituting water density for debris flow density. We describe the relationship between surface velocity and surface kinetic pressure using data from seven laboratory flume experiments. It is consistent with the relationship for single phase flow, which is the measurement principle of the Pitot tube.展开更多
Objective： The aim of our study was to investigate the effect of Cinobufacini injection on the proliferat（on and apoptosis of human hepatocarcinoma HepG-2 cells. Methods： Cells proliferation was assessed by MTT ass...Objective： The aim of our study was to investigate the effect of Cinobufacini injection on the proliferat（on and apoptosis of human hepatocarcinoma HepG-2 cells. Methods： Cells proliferation was assessed by MTT assay, cells morphologic was observed by the inverted microscopy, Annexin V/PI stain was used to detect the apoptosis and necrosis of the tumor ceils. The expression of TOPOI mRNA and TOPO Ⅱ mRNAwere examined by RT-PCR. Results： Cinobufacini injection significantly inhibited HepG-2 cells proliferation in dose- and time-dependent ways. After Cinobufacini injection intervention, HepG-2 cells showed typical morphological changes： cells changed from polygon into round, chromatin looseness and karyolysis were observed. The percentages of apoptosis were 88.49%, 76.02%, 61.73% corresponding to the 48 h interference of 0.42 μg/mL, 0.21 μg/mL, 0.105 μg/mL Cinobufacini injection, perspectively. RT-PCR assay showed that Cinobufacini injection down-regulated TOPOI and TOPO Ⅱ expression at mRNA level. Conclusion： Cinobufacini can inhibit human hepatocarcinoma HepG-2 cells growth and induce tumor cells apoptosis, the mechanism of which might partly relate to the down-regulation of TOPOI mRNA and TOPO Ⅰ mRNA induced by Cinobufacini injection.展开更多
Objective： To study the effect and mechanism of aspirin alone or combined with cisplatin （DDP） on human cervical carcinoma HeLa cells. Methods： HeLa cells were treated by different concentrations of aspirin, DDP a...Objective： To study the effect and mechanism of aspirin alone or combined with cisplatin （DDP） on human cervical carcinoma HeLa cells. Methods： HeLa cells were treated by different concentrations of aspirin, DDP alone or both. The inhibitory effect on cell growth was analyzed by MTT and colony-forming assay. Cell apoptosis was measured with flow cytometry. The mRNA levels ofBcl-2, Bax and NF-κB（P65） were studied by RT-PCR. Results： MTT assay showed that aspirin inhibited HeLa cell proliferation in a time-and dose-dependant maoner. Aspirin decreased clone numbers in colony formation assay. Aspirin also induced apoptosis of HeLa cells in a dose- and time-dependent manner as detected by flow cytometry. The inhibition effects on proliferation, colony formation and apoptosis were significantly enhanced when cells were treated with both aspirin and DDP. RT-PCR demonstrated that aspirin decreased the transcription of Bcl-2 and NF-κB, and increased expression of Bax gene. Conclusion： Aspirin can induce apoptosis in HeLa cells. Combination of aspirin and DDP displays a synergistic effect. The possible mechanism might be that aspirin downregulates the mRNA levels of Bcl-2 and NF-κB gene and upregulates the expression of Bax.展开更多
Objective: The tumor tissues used in molecular pathological detection were usually obtained by surgery, which would cause trauma and may not be suitable for the terminal cancer patients. This paper evaluated the value...Objective: The tumor tissues used in molecular pathological detection were usually obtained by surgery, which would cause trauma and may not be suitable for the terminal cancer patients. This paper evaluated the value of the non-small cell lung cancer(NSCLC) pleural effusion cell blocks as tumor tissues replacement materials in the application of molecular pathological detection. Methods: Tumor cells were made into cell blocks through stratified centrifugal from 30 NSCLC patients with the pleural effusion. The immunohistochemistry, fluorescence in situ hybridization(FISH) and gene sequencing methods were employed in our experiments. Results: The tumor cells of cell block section were rich and could keep part of histological structure. Immunohistochemistry staining could assist diagnosis and tumor parting. Epidermal growth factor receptor(EGFR) FISH-positive was found in 33.33% of the group, high polysomy in 6 cases, amplification in 4 cases. EGFR gene mutations were found in 8 cases of 30 samples, with an incidence of 26.67%, 6 cases were detected in the exon 19, and 2 cases were detected in the exon 21. Conclusion: The NSCLC pleural effusion cell blocks are useful for the diagnosis and determining the primary source of tumor, instructed targeted therapy.展开更多
基金Under the auspices of Key Project of National Natural Science Foundation of China(No.41130534)
文摘The change of impervious surface area(ISA) can effectively reveal the gradual process of urbanization and act as a key index for monitoring urban expansion. Experiencing rapid growth of the built environment in the 2000 s, urban expansion of Beijing has not been fully characterized through ISA. In this study, Landsat TM images of Beijing in 2001 and 2009 were obtained, and the eight-year urban expansion process in Beijing was analyzed using the ISA extracted by means of the vegetation-imperious surface-soil(V-I-S) model. From the spatial variation in ISA, the ring structure of urban expansion in Beijing was significant during the study period, with decreasing urban density from the city center to the periphery. In the ring road analysis, the most dramatic changes of ISA were found between the fifth ring and the sixth ring. This area has experienced the most new residential development, and is currently the main source of urban expansion. The typical profile lines revealed the directional characteristics of urban expansion. The east-west profile was the most urbanized axes in Beijing, while ISA change in the east-north profile was more significant than in the other five profiles. Moreover, the transition matrix of ISA levels revealed an increase in urban density in the low density built areas; the Moran′s I index showed a clear expansion of the central urban area, which spread contiguously; and the standard deviational ellipse indicated the northeast was the dominant direction of urban expansion. These findings can provide important spatial control guidelines in the next round of national economic and social development planning, overall urban and rural planning, and land use planning.
基金supported by the National Natural Science Foundation of China (Grant No. 40771026)the NSFC-RFBR project (Grant No. 40911120089, 08-05-92206 NSFCa)
文摘Measuring the internal velocity of debris flows is very important for debris flow dynamics research and designing debris flow control works. However, there is no appropriate method for measuring the internal velocity because of the destructive power of debris flow process. In this paper, we address this problem by using the relationship between velocity and kinetic pressure, as described by surface velocity and surface kinetic pressure data. Kinetic pressure is the difference of impact pressure and static pressure. The former is detected by force sensors installed in the flow direction at the sampling section. Observations show that static pressure can be computed using the formula for static water pressure by simply substituting water density for debris flow density. We describe the relationship between surface velocity and surface kinetic pressure using data from seven laboratory flume experiments. It is consistent with the relationship for single phase flow, which is the measurement principle of the Pitot tube.
文摘Objective： The aim of our study was to investigate the effect of Cinobufacini injection on the proliferat（on and apoptosis of human hepatocarcinoma HepG-2 cells. Methods： Cells proliferation was assessed by MTT assay, cells morphologic was observed by the inverted microscopy, Annexin V/PI stain was used to detect the apoptosis and necrosis of the tumor ceils. The expression of TOPOI mRNA and TOPO Ⅱ mRNAwere examined by RT-PCR. Results： Cinobufacini injection significantly inhibited HepG-2 cells proliferation in dose- and time-dependent ways. After Cinobufacini injection intervention, HepG-2 cells showed typical morphological changes： cells changed from polygon into round, chromatin looseness and karyolysis were observed. The percentages of apoptosis were 88.49%, 76.02%, 61.73% corresponding to the 48 h interference of 0.42 μg/mL, 0.21 μg/mL, 0.105 μg/mL Cinobufacini injection, perspectively. RT-PCR assay showed that Cinobufacini injection down-regulated TOPOI and TOPO Ⅱ expression at mRNA level. Conclusion： Cinobufacini can inhibit human hepatocarcinoma HepG-2 cells growth and induce tumor cells apoptosis, the mechanism of which might partly relate to the down-regulation of TOPOI mRNA and TOPO Ⅰ mRNA induced by Cinobufacini injection.
基金Supported by the Scientific and Technological Project in Shaanxi Province (2005K09-G6-2)
文摘Objective： To study the effect and mechanism of aspirin alone or combined with cisplatin （DDP） on human cervical carcinoma HeLa cells. Methods： HeLa cells were treated by different concentrations of aspirin, DDP alone or both. The inhibitory effect on cell growth was analyzed by MTT and colony-forming assay. Cell apoptosis was measured with flow cytometry. The mRNA levels ofBcl-2, Bax and NF-κB（P65） were studied by RT-PCR. Results： MTT assay showed that aspirin inhibited HeLa cell proliferation in a time-and dose-dependant maoner. Aspirin decreased clone numbers in colony formation assay. Aspirin also induced apoptosis of HeLa cells in a dose- and time-dependent manner as detected by flow cytometry. The inhibition effects on proliferation, colony formation and apoptosis were significantly enhanced when cells were treated with both aspirin and DDP. RT-PCR demonstrated that aspirin decreased the transcription of Bcl-2 and NF-κB, and increased expression of Bax gene. Conclusion： Aspirin can induce apoptosis in HeLa cells. Combination of aspirin and DDP displays a synergistic effect. The possible mechanism might be that aspirin downregulates the mRNA levels of Bcl-2 and NF-κB gene and upregulates the expression of Bax.
文摘Objective: The tumor tissues used in molecular pathological detection were usually obtained by surgery, which would cause trauma and may not be suitable for the terminal cancer patients. This paper evaluated the value of the non-small cell lung cancer(NSCLC) pleural effusion cell blocks as tumor tissues replacement materials in the application of molecular pathological detection. Methods: Tumor cells were made into cell blocks through stratified centrifugal from 30 NSCLC patients with the pleural effusion. The immunohistochemistry, fluorescence in situ hybridization(FISH) and gene sequencing methods were employed in our experiments. Results: The tumor cells of cell block section were rich and could keep part of histological structure. Immunohistochemistry staining could assist diagnosis and tumor parting. Epidermal growth factor receptor(EGFR) FISH-positive was found in 33.33% of the group, high polysomy in 6 cases, amplification in 4 cases. EGFR gene mutations were found in 8 cases of 30 samples, with an incidence of 26.67%, 6 cases were detected in the exon 19, and 2 cases were detected in the exon 21. Conclusion: The NSCLC pleural effusion cell blocks are useful for the diagnosis and determining the primary source of tumor, instructed targeted therapy.
