A reproducing kernel collocation method based on strong formulation is introduced for transient dynamics. To study the stability property of this method, an algorithm based on the von Neumann hypothesis is proposed to...A reproducing kernel collocation method based on strong formulation is introduced for transient dynamics. To study the stability property of this method, an algorithm based on the von Neumann hypothesis is proposed to predict the critical time step. A numerical test is conducted to validate the algorithm. The numerical critical time step and the predicted critical time step are in good agreement. The results are compared with those obtained based on the radial basis collocation method, and they axe in good agreement. Several important conclusions for choosing a proper support size of the reproducing kernel shape function are given to improve the stability condition.展开更多
AIM： To systematically evaluate the accuracy of 18-fu-orodeoxy-D-glucose-positron emission tomography （18-FDG PET） to assess response to neoadjuvant che-motherapy in bone and soft tissue sarcomas.METHODS： Studies ...AIM： To systematically evaluate the accuracy of 18-fu-orodeoxy-D-glucose-positron emission tomography （18-FDG PET） to assess response to neoadjuvant che-motherapy in bone and soft tissue sarcomas.METHODS： Studies published in English language re-garding the accuracy of F-18 FDG PET for the indication were retrieved from MEDLINE. The QUADAS tool was utilized for methodological quality appraisal. Relevant data were extracted, and quantitative data synthesis included pooled estimation and subgroup analysis. RESULTS： A total of ffteen studies involving 420 pa-tients with pathologically confrmed sarcoma were col-lected. Methodological quality was relatively high. The pooled sensitivity and specifcity of PET to predict histo-pathological response were 87% （95%CI： 81%-91%） and 83% （95%CI： 77%-87%）, respectively. Ten stud-ies employed a lower standardized uptake value （SUV） after chemotherapies （mostly 2.5） and/or a higher SUV reduction rate （mostly around 50%） as PET criteria of good response. Subgroup analysis showed that PET ex-hibited a signifcantly better specifcity in osteosarcoma （OS） and Ewing sarcoma （ES） than in soft-tissue sarco-ma （STS） （91% vs 75%, P 〈 0.05）, and a higher speci-fcity in pediatric patients than in adults （90% vs 74%, P 〈 0.01）. PET yielded a lower specifcity in ifosfamide-contained chemotherapies than in the alternative regi-men （70% vs 97%, P 〈 0.01）.CONCLUSION： F-18 FDG PET is promising to predict neoadjuvant therapy response in sarcoma, especially in pediatric patients with OS or ES. Certain chemothera-peutic agents could potentially cause false positives of PET.展开更多
A new filtering method for SAR data de-noising using wavelet support vector regression （WSVR） is developed. On the basis of the grey scale distribution character of SAR imagery, the logarithmic SAR image as a noise ...A new filtering method for SAR data de-noising using wavelet support vector regression （WSVR） is developed. On the basis of the grey scale distribution character of SAR imagery, the logarithmic SAR image as a noise polluted signal is taken and the noise model assumption in logarithmic domain with Gaussian noise and impact noise is proposed. Based on the better per- formance of support vector regression （SVR） for complex signal approximation and the wavelet for signal detail expression, the wavelet kernel function is chosen as support vector kernel func- tion. Then the logarithmic SAR image is regressed with WSVR. Furthermore the regression distance is used as a judgment index of the noise type. According to the judgment of noise type every pixel can be adaptively de-noised with different filters. Through an approximation experiment for a one-dimensional complex signal, the feasibility of SAR data regression based on WSVR is con- firmed. Afterward the SAR image is treated as a two-dimensional continuous signal and filtered by an SVR with wavelet kernel function. The results show that the method proposed here reduces the radar speckle noise effectively while maintaining edge features and details well.展开更多
A modified version of the Cotte, Lions, Morel and Coil theory for image selective smoothing and edge detection is proposed. Comparing with their model, the most important advantage of this modification is that the con...A modified version of the Cotte, Lions, Morel and Coil theory for image selective smoothing and edge detection is proposed. Comparing with their model, the most important advantage of this modification is that the convolution with Gaussian processes in the filtering process is replaced by solving an initial-boundary value problem for the heat equation, which simplifies the numerical scheme to some extent. Numerical experiments on natural images are presented for this model.展开更多
【目的】克隆小黑杨(Populus×xiaohei T.S.Hwang et Liang)RAV1和RAV2基因,分析这2个基因在非生物胁迫下的表达模式,为进一步研究小黑杨基因功能提供理论依据。【方法】以抗逆性强的小黑杨根为试材,克隆2个RAV家族成员。利用生物...【目的】克隆小黑杨(Populus×xiaohei T.S.Hwang et Liang)RAV1和RAV2基因,分析这2个基因在非生物胁迫下的表达模式,为进一步研究小黑杨基因功能提供理论依据。【方法】以抗逆性强的小黑杨根为试材,克隆2个RAV家族成员。利用生物信息学方法对小黑杨2个RAV基因的理化性质、保守基序、保守结构域、系统进化进行分析,并采用半定量RT-PCR方法探讨这2个基因在小黑杨顶芽、叶、木质部、韧皮部、根、第1~14片叶、第1~11茎节中的表达情况,以及在CdCl2、NaCl、NaHCO3、PEG和ABA胁迫下的表达特性。【结果】从小黑杨中克隆出2个RAV基因,命名为PsnRAV1和PsnRAV2。PsnRAV1编码405个氨基酸,预测分子质量约为99.46 ku,等电点5.06,不存在信号肽;PsnRAV2编码407个氨基酸,预测分子质量约为99.33 ku,等电点5.06,存在信号肽;2个基因均位于细胞核上。保守结构域和保守基序分析结果表明,小黑杨RAV蛋白具有RAV家族特有的AP2和B3这2个保守蛋白结构域,基序1、2、3是构成2个结构域的主要基序。系统进化分析表明,20种植物的RAV蛋白分为3组,其中PsnRAV1和PsnRAV2与毛果杨(Populus trichocarpa)RAV同源性很高。半定量RT-PCR分析结果显示,2个PsnRAVs基因在小黑杨的顶芽、叶、木质部、韧皮部和根中均有表达;且随着叶和茎的发育,2个基因的表达量均呈现升高的趋势。在CdCl2、NaCl、NaHCO3模拟的重金属及盐胁迫下,2个基因的表达模式虽不相同,但在根部均受到诱导;在PEG模拟的干旱胁迫下,PsnRAV1和PsnRAV2在叶片和根部均有响应,其中在根部受到的诱导更为明显,尤以PsnRAV2的表达更为显著;此外,PsnRAV1和PsnRAV2也受到ABA的诱导,其在叶中的表达量在初期表现为上升,而后期下降。【结论】2个PsnRAVs基因与小黑杨的抗逆性密切相关,可能参与了小黑杨的非生物胁迫应答,其中PsnRAV2在胁迫下的作用更为显著。展开更多
Based on an input-output analysis, this paper compiles inventories of fuel-related CO2 emissions of Hubei economy in the years of 2002, 2005, and 2007. Results show that calculated total direct CO2 emissions rose from...Based on an input-output analysis, this paper compiles inventories of fuel-related CO2 emissions of Hubei economy in the years of 2002, 2005, and 2007. Results show that calculated total direct CO2 emissions rose from 114,462.69 kt （2002） to 196,650.31 kt （2005）, reaching 210,419.93 kt in 2007, with an average 22.50% rate of increase. Raw coal was the dominant source of the direct emissions throughout the three years. The sector of Electric Power, Heat Production, and Supply was the main direct emissions contributor, with the largest intensities observed from 2002 （1192.97 g/CNY） to 2007 （1739.15 g/ CNY）. From the industrial perspective, the secondary industry, which is characterized as manufacture of finished products, was still the pillar of the Hubei economy during this period concerned, contributing more than 80% of the total direct emissions. As a net exporter of embodied CO2 emissions in 2002 and 2007, Hubei reported net-exported emissions of 4109.00 kt and 17,871.77 kt respectively; however, Hubei was once a net importer of CO2 emissions in 2005 （2511.93 kt）. The CO2 emissions embodied in export and fixed capital formation had the two leading fractions of emissions embodied in the final use. The corresponding countermeasures, such as promoting renew- able and clean energy and properly reducing the exports of low value added and carbon-intensive products are suggestions for reducing CO2 emissions in Hubei.展开更多
基金Project supported by the Western Transport Technical Project of Ministry of Transport of China(No. 2009318000046)
文摘A reproducing kernel collocation method based on strong formulation is introduced for transient dynamics. To study the stability property of this method, an algorithm based on the von Neumann hypothesis is proposed to predict the critical time step. A numerical test is conducted to validate the algorithm. The numerical critical time step and the predicted critical time step are in good agreement. The results are compared with those obtained based on the radial basis collocation method, and they axe in good agreement. Several important conclusions for choosing a proper support size of the reproducing kernel shape function are given to improve the stability condition.
基金Supported by Scientific Research Subject of Health Department of Sichuan,China,No.070045
文摘AIM： To systematically evaluate the accuracy of 18-fu-orodeoxy-D-glucose-positron emission tomography （18-FDG PET） to assess response to neoadjuvant che-motherapy in bone and soft tissue sarcomas.METHODS： Studies published in English language re-garding the accuracy of F-18 FDG PET for the indication were retrieved from MEDLINE. The QUADAS tool was utilized for methodological quality appraisal. Relevant data were extracted, and quantitative data synthesis included pooled estimation and subgroup analysis. RESULTS： A total of ffteen studies involving 420 pa-tients with pathologically confrmed sarcoma were col-lected. Methodological quality was relatively high. The pooled sensitivity and specifcity of PET to predict histo-pathological response were 87% （95%CI： 81%-91%） and 83% （95%CI： 77%-87%）, respectively. Ten stud-ies employed a lower standardized uptake value （SUV） after chemotherapies （mostly 2.5） and/or a higher SUV reduction rate （mostly around 50%） as PET criteria of good response. Subgroup analysis showed that PET ex-hibited a signifcantly better specifcity in osteosarcoma （OS） and Ewing sarcoma （ES） than in soft-tissue sarco-ma （STS） （91% vs 75%, P 〈 0.05）, and a higher speci-fcity in pediatric patients than in adults （90% vs 74%, P 〈 0.01）. PET yielded a lower specifcity in ifosfamide-contained chemotherapies than in the alternative regi-men （70% vs 97%, P 〈 0.01）.CONCLUSION： F-18 FDG PET is promising to predict neoadjuvant therapy response in sarcoma, especially in pediatric patients with OS or ES. Certain chemothera-peutic agents could potentially cause false positives of PET.
基金supported by Shanghai Science and Technology Commission Innovation Action Plan(08DZ1205708)
文摘A new filtering method for SAR data de-noising using wavelet support vector regression （WSVR） is developed. On the basis of the grey scale distribution character of SAR imagery, the logarithmic SAR image as a noise polluted signal is taken and the noise model assumption in logarithmic domain with Gaussian noise and impact noise is proposed. Based on the better per- formance of support vector regression （SVR） for complex signal approximation and the wavelet for signal detail expression, the wavelet kernel function is chosen as support vector kernel func- tion. Then the logarithmic SAR image is regressed with WSVR. Furthermore the regression distance is used as a judgment index of the noise type. According to the judgment of noise type every pixel can be adaptively de-noised with different filters. Through an approximation experiment for a one-dimensional complex signal, the feasibility of SAR data regression based on WSVR is con- firmed. Afterward the SAR image is treated as a two-dimensional continuous signal and filtered by an SVR with wavelet kernel function. The results show that the method proposed here reduces the radar speckle noise effectively while maintaining edge features and details well.
基金Partially supported by National Natural Science Foundation and the Shanghai Qimingxing grant. # 97QA14040
文摘A modified version of the Cotte, Lions, Morel and Coil theory for image selective smoothing and edge detection is proposed. Comparing with their model, the most important advantage of this modification is that the convolution with Gaussian processes in the filtering process is replaced by solving an initial-boundary value problem for the heat equation, which simplifies the numerical scheme to some extent. Numerical experiments on natural images are presented for this model.
基金Acknowledgements The authors acknowledge financial support from the National Natural Science Foundation of China （Grant Nos. 51306067 and 51376076）.
文摘Based on an input-output analysis, this paper compiles inventories of fuel-related CO2 emissions of Hubei economy in the years of 2002, 2005, and 2007. Results show that calculated total direct CO2 emissions rose from 114,462.69 kt （2002） to 196,650.31 kt （2005）, reaching 210,419.93 kt in 2007, with an average 22.50% rate of increase. Raw coal was the dominant source of the direct emissions throughout the three years. The sector of Electric Power, Heat Production, and Supply was the main direct emissions contributor, with the largest intensities observed from 2002 （1192.97 g/CNY） to 2007 （1739.15 g/ CNY）. From the industrial perspective, the secondary industry, which is characterized as manufacture of finished products, was still the pillar of the Hubei economy during this period concerned, contributing more than 80% of the total direct emissions. As a net exporter of embodied CO2 emissions in 2002 and 2007, Hubei reported net-exported emissions of 4109.00 kt and 17,871.77 kt respectively; however, Hubei was once a net importer of CO2 emissions in 2005 （2511.93 kt）. The CO2 emissions embodied in export and fixed capital formation had the two leading fractions of emissions embodied in the final use. The corresponding countermeasures, such as promoting renew- able and clean energy and properly reducing the exports of low value added and carbon-intensive products are suggestions for reducing CO2 emissions in Hubei.
