为探究棉花海陆回交群体盛铃期的光合特性及其生理基础,筛选海陆杂交后代高光效种质资源,以陆地棉‘系9’为母本、海岛棉‘新海16’为父本构建的115份BC4F2:4株系群体为研究对象,测定其在田间条件下的光合参数及生理生化指标,利用描述...为探究棉花海陆回交群体盛铃期的光合特性及其生理基础,筛选海陆杂交后代高光效种质资源,以陆地棉‘系9’为母本、海岛棉‘新海16’为父本构建的115份BC4F2:4株系群体为研究对象,测定其在田间条件下的光合参数及生理生化指标,利用描述性统计、相关性分析、回归分析、主成分分析和聚类分析评价子代株系的育种潜力。结果表明,回交群体的15个性状变异丰富,变异系数在8.96%~51.09%,其中净光合速率、蒸腾速率、水分利用效率、胞间CO_(2)浓度、气孔导度、水蒸气压亏缺、丙二醛含量、可溶性蛋白含量和超氧化物歧化酶活性9个性状变异系数均在20%以上。相关性分析发现,海陆回交群体不仅在光合或生理生化指标各自内部存在显著相关性,在光合与生理生化指标之间也存在显著相关性,其中叶绿素相对值(soil and plant analyzer develotrnent,SPAD)与14个性状的相关性均达到显著水平。多元逐步回归分析构建出10个光合生理指标的最佳回归方程。主成分分析提取了5个主成分,累计贡献率达78.608%,第1和第4主成分有效解释群体生理指标,第2、第3和第5主成分有效解释群体光合性状。Ward.D层次聚类法将群体划分为4类,第Ⅰ、第Ⅱ、第Ⅲ和第Ⅳ类群占总材料的百分比分别为33.91%、10.43%、29.57%和26.09%,且第Ⅳ类群的30份材料是综合性状较好的棉花种质,可作为适合育种需要的高光效品系。研究结果为棉花高光效育种提供了理论依据及材料支撑。展开更多
High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ...High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ceramics by adjusting the proportion of raw materials,and have broad application prospects in many fields.This article provides a review of the high entropy effect,preparation methods,and main applications of high entropy ceramic materials,especially exploring relevant research on high entropy perovskite ceramics.It is expected to provide reference for the promotion of scientific research and the development of further large-scale applications of high-entropy ceramic materials.展开更多
Background:Tumour mutational burden(TMB)has emerged as a predictive marker for responsiveness to immune checkpoint inhibitors(ICI)in multiple tumour types.It can be calculated from somatic mutations detected from whol...Background:Tumour mutational burden(TMB)has emerged as a predictive marker for responsiveness to immune checkpoint inhibitors(ICI)in multiple tumour types.It can be calculated from somatic mutations detected from whole exome or targeted panel sequencing data.As mutations are unevenly distributed across the cancer genome,the clinical implications from TMB calculated using different genomic regions are not clear.Methods:Pan-cancer data of 10,179 samples were collected from The Cancer Genome Atlas cohort and 6,831 cancer patients with either ICI or non-ICI treatment outcomes were derived from published papers.TMB was calculated as the count of non-synonymous mutations and normalised by the size of genomic regions.Dirichlet method,linear regression and Poisson calibration models are used to unify TMB from different gene panels.Results:We found that panels based on cancer genes usually overestimate TMB compared to whole exome,potentially leading to misclassification of patients to receive ICI.The overestimation is caused by positive selection for mutations in cancer genes and cannot be completely addressed by the removal of mutational hotspots.We compared different approaches to address this discrepancy and developed a generalised statistical model capable of interconverting TMB derived from whole exome and different panel sequencing data,enabling TMB correction for patient stratification for ICI treatment.We show that in a cohort of lung cancer patients treated with ICI,when using a TMB cutoffof 10 mut/Mb,our corrected TMB outperforms the original panel-based TMB.Conclusion:Cancer gene-based panels usually overestimate TMB,and these findings will be valuable for unifying TMB calculations across cancer gene panels in clinical practice.展开更多
文摘为探究棉花海陆回交群体盛铃期的光合特性及其生理基础,筛选海陆杂交后代高光效种质资源,以陆地棉‘系9’为母本、海岛棉‘新海16’为父本构建的115份BC4F2:4株系群体为研究对象,测定其在田间条件下的光合参数及生理生化指标,利用描述性统计、相关性分析、回归分析、主成分分析和聚类分析评价子代株系的育种潜力。结果表明,回交群体的15个性状变异丰富,变异系数在8.96%~51.09%,其中净光合速率、蒸腾速率、水分利用效率、胞间CO_(2)浓度、气孔导度、水蒸气压亏缺、丙二醛含量、可溶性蛋白含量和超氧化物歧化酶活性9个性状变异系数均在20%以上。相关性分析发现,海陆回交群体不仅在光合或生理生化指标各自内部存在显著相关性,在光合与生理生化指标之间也存在显著相关性,其中叶绿素相对值(soil and plant analyzer develotrnent,SPAD)与14个性状的相关性均达到显著水平。多元逐步回归分析构建出10个光合生理指标的最佳回归方程。主成分分析提取了5个主成分,累计贡献率达78.608%,第1和第4主成分有效解释群体生理指标,第2、第3和第5主成分有效解释群体光合性状。Ward.D层次聚类法将群体划分为4类,第Ⅰ、第Ⅱ、第Ⅲ和第Ⅳ类群占总材料的百分比分别为33.91%、10.43%、29.57%和26.09%,且第Ⅳ类群的30份材料是综合性状较好的棉花种质,可作为适合育种需要的高光效品系。研究结果为棉花高光效育种提供了理论依据及材料支撑。
文摘High-entropy materials(HEMs)have better mechanical,thermal,and electrical properties than traditional materials due to their special"high entropy effect".They can also adjust the performance of high entropy ceramics by adjusting the proportion of raw materials,and have broad application prospects in many fields.This article provides a review of the high entropy effect,preparation methods,and main applications of high entropy ceramic materials,especially exploring relevant research on high entropy perovskite ceramics.It is expected to provide reference for the promotion of scientific research and the development of further large-scale applications of high-entropy ceramic materials.
基金supported by the Research Grants Council,HK(grant number:17100920)seed funding from The University of Hong Kong.
文摘Background:Tumour mutational burden(TMB)has emerged as a predictive marker for responsiveness to immune checkpoint inhibitors(ICI)in multiple tumour types.It can be calculated from somatic mutations detected from whole exome or targeted panel sequencing data.As mutations are unevenly distributed across the cancer genome,the clinical implications from TMB calculated using different genomic regions are not clear.Methods:Pan-cancer data of 10,179 samples were collected from The Cancer Genome Atlas cohort and 6,831 cancer patients with either ICI or non-ICI treatment outcomes were derived from published papers.TMB was calculated as the count of non-synonymous mutations and normalised by the size of genomic regions.Dirichlet method,linear regression and Poisson calibration models are used to unify TMB from different gene panels.Results:We found that panels based on cancer genes usually overestimate TMB compared to whole exome,potentially leading to misclassification of patients to receive ICI.The overestimation is caused by positive selection for mutations in cancer genes and cannot be completely addressed by the removal of mutational hotspots.We compared different approaches to address this discrepancy and developed a generalised statistical model capable of interconverting TMB derived from whole exome and different panel sequencing data,enabling TMB correction for patient stratification for ICI treatment.We show that in a cohort of lung cancer patients treated with ICI,when using a TMB cutoffof 10 mut/Mb,our corrected TMB outperforms the original panel-based TMB.Conclusion:Cancer gene-based panels usually overestimate TMB,and these findings will be valuable for unifying TMB calculations across cancer gene panels in clinical practice.
