基因组拷贝数变异(copy number variations,CNVs)是指与基因组参考序列相比,基因组中≥1kb的DNA片段插入、缺失和/或扩增,及其互相组合衍生出的复杂变异.由于其具有分布范围广、可遗传、相对稳定和高度异质性等特点,目前认为,CNVs是一...基因组拷贝数变异(copy number variations,CNVs)是指与基因组参考序列相比,基因组中≥1kb的DNA片段插入、缺失和/或扩增,及其互相组合衍生出的复杂变异.由于其具有分布范围广、可遗传、相对稳定和高度异质性等特点,目前认为,CNVs是一种新的可以作为疾病易感标志的基因组DNA多态性,其变异引起的基因剂量改变可以导致表型改变.最近,一种基于CNVs的新的疾病易感基因鉴定策略——CNV全基因组关联分析开始出现,这一策略和传统的基于单核苷酸多态性的关联分析具有互补性,通过认识基因组结构变异可以认识复杂疾病的分子机制和遗传基础.展开更多
Applications of Atomic Force Microscopy (AFM) in optical disc technology are summarized. AFM is ideally suited to the characterization of nanometerscale pit and bump structures in CD/DVD manufacturing, so the relati...Applications of Atomic Force Microscopy (AFM) in optical disc technology are summarized. AFM is ideally suited to the characterization of nanometerscale pit and bump structures in CD/DVD manufacturing, so the relationship between production variables and pits/bumps geometry as well as relations between pits/bumps geometry and electrical performance of discs can be established to perform direct quality control of CD/DVD manufacturing. Applications of AFM in optical disc technology mainly fall into three parts: qualitative analysis of topography of discs/stampers, semiquantitative analysis of pits/bumps geometry of discs/stampers and length analysis of data marks on bump with statistics technology. Qualitative analysis of topography of discs/stampers and semiquantitative analysis of pits/bumps geometry of discs/stampers are chiefly oriented to the measurements of high error rate at beginning of play, pit morphology and block error rate, track pitch variations, pit depth monitoring as well as bump morphology and its surface roughness. It is discovered that the efficiency of the cooling channels of the mold has deteriorated, resulting in the discs being separated from the stamper while they are too soft due to inadequate cooling in the area where high error rate and block error rate are frequently produced. Length analysis of data marks with statistics technology is aimed at the analysis of track pitch and pitch variation, bump length (offset, deviation, asymmetry) and AFM jitter, bump width and width variation, bump height and height variation as well as side wall angle (slope) and slope variation. Statistical analysis of AFM images yields important information about optical disc microstructure and in turn provides information about the performance of the manufacturing process. It is very useful to analyze geometric parameters by considering the fundamental length groups of the data marks. The obtained results demonstrate that AFM have particular advantages in the quality control of discs/stampers manufacturing.展开更多
A high performance red-sensitive holographic recording material was studied.After acrylic acid was added into PPA system,the holograms of high diffraction efficiency,which was stable in high humidty environment for a ...A high performance red-sensitive holographic recording material was studied.After acrylic acid was added into PPA system,the holograms of high diffraction efficiency,which was stable in high humidty environment for a long time,were obtained.展开更多
文摘基因组拷贝数变异(copy number variations,CNVs)是指与基因组参考序列相比,基因组中≥1kb的DNA片段插入、缺失和/或扩增,及其互相组合衍生出的复杂变异.由于其具有分布范围广、可遗传、相对稳定和高度异质性等特点,目前认为,CNVs是一种新的可以作为疾病易感标志的基因组DNA多态性,其变异引起的基因剂量改变可以导致表型改变.最近,一种基于CNVs的新的疾病易感基因鉴定策略——CNV全基因组关联分析开始出现,这一策略和传统的基于单核苷酸多态性的关联分析具有互补性,通过认识基因组结构变异可以认识复杂疾病的分子机制和遗传基础.
文摘Applications of Atomic Force Microscopy (AFM) in optical disc technology are summarized. AFM is ideally suited to the characterization of nanometerscale pit and bump structures in CD/DVD manufacturing, so the relationship between production variables and pits/bumps geometry as well as relations between pits/bumps geometry and electrical performance of discs can be established to perform direct quality control of CD/DVD manufacturing. Applications of AFM in optical disc technology mainly fall into three parts: qualitative analysis of topography of discs/stampers, semiquantitative analysis of pits/bumps geometry of discs/stampers and length analysis of data marks on bump with statistics technology. Qualitative analysis of topography of discs/stampers and semiquantitative analysis of pits/bumps geometry of discs/stampers are chiefly oriented to the measurements of high error rate at beginning of play, pit morphology and block error rate, track pitch variations, pit depth monitoring as well as bump morphology and its surface roughness. It is discovered that the efficiency of the cooling channels of the mold has deteriorated, resulting in the discs being separated from the stamper while they are too soft due to inadequate cooling in the area where high error rate and block error rate are frequently produced. Length analysis of data marks with statistics technology is aimed at the analysis of track pitch and pitch variation, bump length (offset, deviation, asymmetry) and AFM jitter, bump width and width variation, bump height and height variation as well as side wall angle (slope) and slope variation. Statistical analysis of AFM images yields important information about optical disc microstructure and in turn provides information about the performance of the manufacturing process. It is very useful to analyze geometric parameters by considering the fundamental length groups of the data marks. The obtained results demonstrate that AFM have particular advantages in the quality control of discs/stampers manufacturing.
文摘A high performance red-sensitive holographic recording material was studied.After acrylic acid was added into PPA system,the holograms of high diffraction efficiency,which was stable in high humidty environment for a long time,were obtained.
