Offset-tracking is an essential method for deriving glacier flow rates using optical imagery.Sentinel-2(S2)and Landsat-8/9(L8/9)are popular optical satellites or constellations for polar studies,offering high spatial ...Offset-tracking is an essential method for deriving glacier flow rates using optical imagery.Sentinel-2(S2)and Landsat-8/9(L8/9)are popular optical satellites or constellations for polar studies,offering high spatial resolution with relatively short revisit time,wide swath width,and free accessibility.To evaluate and compare the precision of offset-tracking results yielded with these two kinds of data,in this study S2 and L8/9 imagery observed in Petermann Glacier in Greenland,Karakoram in High-Mountains Asia,and Amery Ice Shelf in the Antarctic are analyzed.Outliers and various systematic error sources in the offset-tracking results including orbital and strip errors were analyzed and eliminated at the pre-process stage.Precision at the off-glacier(bare rock)region was evaluated by presuming that no deformation occurred;then for both glacierized and the off-glacier regions,precision of velocity time series was evaluated based on error propagation theory.The least squares method based on connected components was used to solve flow rates time series based on multi-pair images offset-tracking.The results indicated that S2 achieved slightly higher precision than L8/9 in terms of both single-pair derived displacements and least square solved daily flow rates time series.Generally,the RMSE of daily velocity is 26%lower for S2 than L8/9.Moreover,S2 provided higher temporal resolution for monitoring glacier flow rates.展开更多
目的探讨β胶原特殊序列(β-crosslaps,β-CTX)、总1型胶原氨基端延长肽(t-P1NP)及N端中段骨钙素(N-MID-OT)在绝经后女性骨质疏松性骨折风险评估中的应用价值。方法回顾性分析2020年2月至2022年12月解放军总医院第六医学中心收治的102...目的探讨β胶原特殊序列(β-crosslaps,β-CTX)、总1型胶原氨基端延长肽(t-P1NP)及N端中段骨钙素(N-MID-OT)在绝经后女性骨质疏松性骨折风险评估中的应用价值。方法回顾性分析2020年2月至2022年12月解放军总医院第六医学中心收治的102例绝经后骨质疏松(postmenopausal osteoporosis,PMOP)患者的临床资料,将其作为研究组,并根据是否发生骨折将其分为PMOP骨折组(39例)与PMOP未骨折组(63例),另选100名健康体检者作为对照组。记录所有研究对象的β-CTX、t-P1NP及N-MID-OT水平并进行比较,用ROC曲线评价β-CTX、t-P1NP及N-MID-OT在绝经后女性骨质疏松性骨折风险评估中的应用价值。结果研究组的平均体重、体质量指数、股骨颈骨密度(bone mineral density,BMD)、左髋总和BMD及L 1~4总和BMD均明显低于对照组(P<0.05);而两组研究对象的平均年龄、平均身高及绝经年龄等比较差异均无统计学意义(P>0.05)。研究组的β-CTX、t-P1NP及N-MID-OT均明显高于对照组(t值依次为12.688、37.430、26.599,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于预测PMOP的AUC值为0.978,敏感度为98.04%,特异度为97.00%,表明β-CTX+t-P1NP+N-MID-OT三指标联合检测用于预测PMOP的效能更高。PMOP骨折组的β-CTX、t-P1NP及N-MID-OT均明显高于PMOP未骨折组(t值依次为6.078、16.363、12.227,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的AUC值为0.939,敏感度为94.87%,特异度为95.24%,表明β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的效能更高。结论PMOP患者β-CTX、t-P1NP及N-MID-OT水平均明显升高,而PMOP骨折患者β-CTX、t-P1NP及N-MID-OT水平升高更为明显,且β-CTX+t-P1NP+N-MID-OT联合检测可显著提高对PMOP预测及骨折风险评估效能,值得借鉴。展开更多
The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed widely.However,the mechanism by which it promotes colon cancer remain...The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed widely.However,the mechanism by which it promotes colon cancer remains unclear.Retrovirnl vector pSEB61 was retroftted in established HCT116 siKCN and SW480-siKCN cells to silence KCNQ1 OT1.Cellular proliferation was measured using CCK8 assay,and flow cytometry(FCM)detected cell cydle changes.RNA sequencing(RNA Seq)analysis showed differentially expressed genes(DEGs).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were carried out to analyze enriched functions and signaling pathways.RT-qPCR,immunofluorescence,and western blotting were carried out to validate downstream gene expressions.The effects of tumorigenesis were evaluated in BALB/c nude mice by tumor xenografts.Our data revealed that the silencing of KONQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M phase.RNA-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell cyde.RT qPCR,immunofluorescence,and western blotting confirmed downstream CCNE2 and PCNA gene expressions.HCT116 siKCN cells signifcantly suppressed tumorigenesis in BALB/c nude mice.Our study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer.展开更多
Two rupture zones of Wenchuan earthquake have been successfully located by an offset-tracking procedure of ENVISAT ASAR amplitude images.Accuracy of offset-tracking strongly depends on the quality of image coregistrat...Two rupture zones of Wenchuan earthquake have been successfully located by an offset-tracking procedure of ENVISAT ASAR amplitude images.Accuracy of offset-tracking strongly depends on the quality of image coregistration.In order to remove noise caused by coregistration,a combined filter method is proposed to remove noise of estimated offsets.In addition,Kriging interpolation is applied to smooth the azimuth displacement offset map.The displacement offset maps of azimuth and range show that about 245 km and 60 km in length along Beichuan-Yingxiu fault and Guanxian-Jiangyou fault were ruptured by Wenchuan earthquake,respectively.The result of offset-tracking is validated by field observations of China Earthquake Administration.展开更多
基金supported by the National Natural Science Foundation of China(Grant no.42371136)the Guangdong Basic and Applied Basic Research Foundation(Grant no.2021B1515020032)the Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(Grant no.311022003).
文摘Offset-tracking is an essential method for deriving glacier flow rates using optical imagery.Sentinel-2(S2)and Landsat-8/9(L8/9)are popular optical satellites or constellations for polar studies,offering high spatial resolution with relatively short revisit time,wide swath width,and free accessibility.To evaluate and compare the precision of offset-tracking results yielded with these two kinds of data,in this study S2 and L8/9 imagery observed in Petermann Glacier in Greenland,Karakoram in High-Mountains Asia,and Amery Ice Shelf in the Antarctic are analyzed.Outliers and various systematic error sources in the offset-tracking results including orbital and strip errors were analyzed and eliminated at the pre-process stage.Precision at the off-glacier(bare rock)region was evaluated by presuming that no deformation occurred;then for both glacierized and the off-glacier regions,precision of velocity time series was evaluated based on error propagation theory.The least squares method based on connected components was used to solve flow rates time series based on multi-pair images offset-tracking.The results indicated that S2 achieved slightly higher precision than L8/9 in terms of both single-pair derived displacements and least square solved daily flow rates time series.Generally,the RMSE of daily velocity is 26%lower for S2 than L8/9.Moreover,S2 provided higher temporal resolution for monitoring glacier flow rates.
文摘目的探讨β胶原特殊序列(β-crosslaps,β-CTX)、总1型胶原氨基端延长肽(t-P1NP)及N端中段骨钙素(N-MID-OT)在绝经后女性骨质疏松性骨折风险评估中的应用价值。方法回顾性分析2020年2月至2022年12月解放军总医院第六医学中心收治的102例绝经后骨质疏松(postmenopausal osteoporosis,PMOP)患者的临床资料,将其作为研究组,并根据是否发生骨折将其分为PMOP骨折组(39例)与PMOP未骨折组(63例),另选100名健康体检者作为对照组。记录所有研究对象的β-CTX、t-P1NP及N-MID-OT水平并进行比较,用ROC曲线评价β-CTX、t-P1NP及N-MID-OT在绝经后女性骨质疏松性骨折风险评估中的应用价值。结果研究组的平均体重、体质量指数、股骨颈骨密度(bone mineral density,BMD)、左髋总和BMD及L 1~4总和BMD均明显低于对照组(P<0.05);而两组研究对象的平均年龄、平均身高及绝经年龄等比较差异均无统计学意义(P>0.05)。研究组的β-CTX、t-P1NP及N-MID-OT均明显高于对照组(t值依次为12.688、37.430、26.599,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于预测PMOP的AUC值为0.978,敏感度为98.04%,特异度为97.00%,表明β-CTX+t-P1NP+N-MID-OT三指标联合检测用于预测PMOP的效能更高。PMOP骨折组的β-CTX、t-P1NP及N-MID-OT均明显高于PMOP未骨折组(t值依次为6.078、16.363、12.227,P<0.05)。β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的AUC值为0.939,敏感度为94.87%,特异度为95.24%,表明β-CTX+t-P1NP+N-MID-OT联合检测用于评估PMOP骨折风险的效能更高。结论PMOP患者β-CTX、t-P1NP及N-MID-OT水平均明显升高,而PMOP骨折患者β-CTX、t-P1NP及N-MID-OT水平升高更为明显,且β-CTX+t-P1NP+N-MID-OT联合检测可显著提高对PMOP预测及骨折风险评估效能,值得借鉴。
基金the Scientific Research Project of Anhui Provincial Health Commission in 2021(#AHWJ2021b109 to LS)Scientific and Technological Research Program of Chongqing Municipal Education Commission(#KJZD-K201900402 to TZ)+1 种基金Special Fund for Wannan Medical College Scholar Project(#WK2021F07)Educational Commission of Anhui Province of China(2022AH051241).
文摘The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed widely.However,the mechanism by which it promotes colon cancer remains unclear.Retrovirnl vector pSEB61 was retroftted in established HCT116 siKCN and SW480-siKCN cells to silence KCNQ1 OT1.Cellular proliferation was measured using CCK8 assay,and flow cytometry(FCM)detected cell cydle changes.RNA sequencing(RNA Seq)analysis showed differentially expressed genes(DEGs).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were carried out to analyze enriched functions and signaling pathways.RT-qPCR,immunofluorescence,and western blotting were carried out to validate downstream gene expressions.The effects of tumorigenesis were evaluated in BALB/c nude mice by tumor xenografts.Our data revealed that the silencing of KONQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M phase.RNA-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell cyde.RT qPCR,immunofluorescence,and western blotting confirmed downstream CCNE2 and PCNA gene expressions.HCT116 siKCN cells signifcantly suppressed tumorigenesis in BALB/c nude mice.Our study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer.
基金sponsored by the Special Item of Professional Fund for Basic Scientific Research of Chinese Central-Level Public-Welfare College/Institute from Chinese Finance Department (ZDJ2009-36)National Natural Science Foundation of China (40774023)+1 种基金National 863 Program of China (2006AA12Z150)the project Dragon 2 (5343)
文摘Two rupture zones of Wenchuan earthquake have been successfully located by an offset-tracking procedure of ENVISAT ASAR amplitude images.Accuracy of offset-tracking strongly depends on the quality of image coregistration.In order to remove noise caused by coregistration,a combined filter method is proposed to remove noise of estimated offsets.In addition,Kriging interpolation is applied to smooth the azimuth displacement offset map.The displacement offset maps of azimuth and range show that about 245 km and 60 km in length along Beichuan-Yingxiu fault and Guanxian-Jiangyou fault were ruptured by Wenchuan earthquake,respectively.The result of offset-tracking is validated by field observations of China Earthquake Administration.
