Conventional multiple breath-hold two-dimensional （2D） balanced steady-state free precession （SSFP） presents many difficulties in cardiac cine magnetic resonance imaging （MRI）. Recently, a self-gated free-breath...Conventional multiple breath-hold two-dimensional （2D） balanced steady-state free precession （SSFP） presents many difficulties in cardiac cine magnetic resonance imaging （MRI）. Recently, a self-gated free-breathing three-dimensional （3D） SSFP technique has been proposed as an alternative in many studies. However, the accuracy and effectiveness of selfgating signals have been barely studied before. Since self-gating signals are crucially important in image reconstruction, a systematic study of self-gating signals and comparison with external monitored signals are needed. Previously developed self-gated free-breathing 3D SSFP techniques are used on twenty-eight healthy volunteers. Both electrocardiographic （ECG） and respiratory bellow signals are also acquired during the scan as external signals. Self-gating signal and external signal are compared by trigger and gating window. Gating window is proposed to evaluate the accuracy and effectiveness of respiratory self-gating signal. Relative deviation of the trigger and root-mean-square-deviation of the cycle duration are calculated. A two-tailed paired t-test is used to identify the difference between self-gating and external signals. A Wilcoxon signed rank test is used to identify the difference between peak and valley self-gating triggers. The results demonstrate an excellent correlation （P = 0, R 〉 0.99） between self-gating and external triggers. Wilcoxon signed rank test shows that there is no significant difference between peak and valley self-gating triggers for both cardiac （H = 0, P 〉 0.10） and respiratory （H = 0, P 〉 0.44） motions. The difference between self-gating and externally monitored signals is not significant （two-tailed paired-sample t-test： H = 0, P 〉 0.90）. The self-gating signals could demonstrate cardiac and respiratory motion accurately and effectively as ECG and respiratory bellow. The difference between the two methods is not significant and can be explained. Furthermore, few ECG trigger errors appear in some subjects while these errors are not found in self-gating signals.展开更多
9月22日,索尼中国专业系统集团在北京AIT索尼影像技术学院隆重举行Cine Alta V电影摄影机发布会,作为索尼Cine Alta摄影机系统的新一代产品,同时也是影视行业的第一款采用全画幅CMOS（36.2×24.1mm）的摄影机,Cine Alta V面世的消息...9月22日,索尼中国专业系统集团在北京AIT索尼影像技术学院隆重举行Cine Alta V电影摄影机发布会,作为索尼Cine Alta摄影机系统的新一代产品,同时也是影视行业的第一款采用全画幅CMOS（36.2×24.1mm）的摄影机,Cine Alta V面世的消息自9月发布以来便引发了影视行业用户持续的关注和讨论。发布会上,索尼专家和产品经理详解其性能优势、研发背景和多项突破性的＂业界第一＂,并与媒体、业界用户以现场问答、网络直播的方式进行互动,力求全面、精确、展开更多
This paper presents a nonlinear profile order scheme for three-dimensional（3D） hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging（MRI）. In self-gated, free-brea...This paper presents a nonlinear profile order scheme for three-dimensional（3D） hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging（MRI）. In self-gated, free-breathing cardiac cine MRI,respiratory and cardiac motions are unpredictable during acquisition, especially for retrospective reconstruction. Therefore,the non-uniformity of the k-space distribution is an issue of great concern during retrospective self-gated reconstruction. A nonlinear profile order with varying azimuthal increments was provided and compared with the existing golden ratio-based profile order. Optimal parameter values for the nonlinear formula were chosen based on simulations. The two profile orders were compared in terms of the k-space distribution and phantom and human image results. An approximately uniform distribution was obtained based on the nonlinear profile order for persons with various heart rates and breathing patterns.The nonlinear profile order provides more stable profile distributions and fewer streaking artifacts in phantom images. In a comparison of human cardiac cine images, the nonlinear profile order provided results comparable to those provided by the golden ratio-based profile order, and the images were suitable for diagnosis. In conclusion, the nonlinear profile order scheme was demonstrated to be insensitive to various motion patterns and more useful for retrospective reconstruction.展开更多
2006年8月16日，柯达数字影院公司（Kodak Digital Cinema）宣布该公司已经与美国国家影院媒体公司（NCM—National Cine Media）达成协议，联合开发下一代数字影院管理系统（TMS）。这套新的开放式设计的影院管理系统将整合现有的放映...2006年8月16日，柯达数字影院公司（Kodak Digital Cinema）宣布该公司已经与美国国家影院媒体公司（NCM—National Cine Media）达成协议，联合开发下一代数字影院管理系统（TMS）。这套新的开放式设计的影院管理系统将整合现有的放映设备、管理系统和来自其它厂商的数字影院系统部件。展开更多
2月27日,影视行业从业者与爱好者们齐聚北京,共同参与了“Blackmagic URSA Cine 12K电影摄影机工作坊”活动。此次活动为大家提供了深入了解Blackmagic URSA Cine 12K电影摄影机以及交流分享的机会,参与者积极体验,交流氛围热烈。活动伊...2月27日,影视行业从业者与爱好者们齐聚北京,共同参与了“Blackmagic URSA Cine 12K电影摄影机工作坊”活动。此次活动为大家提供了深入了解Blackmagic URSA Cine 12K电影摄影机以及交流分享的机会,参与者积极体验,交流氛围热烈。活动伊始,Blackmagic Design中国区总经理曹晨辉对品牌进行了基本介绍(如图1)。展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.81501463,61471349,81671853,81571669,and 61671026)the National High Technology Research and Development Program of China(Grant No.2015AA043203)+5 种基金the Natural Science Foundation of Beijing,China(Grant No.7162112)Guangdong Innovative Research Team Program of China(Grant No.2011S013)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2014A030310360 and 2014A0202015028)the Beijing Center for Mathematics and Information Interdisciplinary Sciences,Shenzhen Fundamental Research Program,China(Grant Nos.JCYJ201500731154850923 and JCYJ20140417113430665)Shenzhen High-level Oversea Talent Program,China(Grant No.KQJSCX20160301144248)the Nanshan Technology Research Fund,China(Grant No.KC2014JSQN0001A)
文摘Conventional multiple breath-hold two-dimensional （2D） balanced steady-state free precession （SSFP） presents many difficulties in cardiac cine magnetic resonance imaging （MRI）. Recently, a self-gated free-breathing three-dimensional （3D） SSFP technique has been proposed as an alternative in many studies. However, the accuracy and effectiveness of selfgating signals have been barely studied before. Since self-gating signals are crucially important in image reconstruction, a systematic study of self-gating signals and comparison with external monitored signals are needed. Previously developed self-gated free-breathing 3D SSFP techniques are used on twenty-eight healthy volunteers. Both electrocardiographic （ECG） and respiratory bellow signals are also acquired during the scan as external signals. Self-gating signal and external signal are compared by trigger and gating window. Gating window is proposed to evaluate the accuracy and effectiveness of respiratory self-gating signal. Relative deviation of the trigger and root-mean-square-deviation of the cycle duration are calculated. A two-tailed paired t-test is used to identify the difference between self-gating and external signals. A Wilcoxon signed rank test is used to identify the difference between peak and valley self-gating triggers. The results demonstrate an excellent correlation （P = 0, R 〉 0.99） between self-gating and external triggers. Wilcoxon signed rank test shows that there is no significant difference between peak and valley self-gating triggers for both cardiac （H = 0, P 〉 0.10） and respiratory （H = 0, P 〉 0.44） motions. The difference between self-gating and externally monitored signals is not significant （two-tailed paired-sample t-test： H = 0, P 〉 0.90）. The self-gating signals could demonstrate cardiac and respiratory motion accurately and effectively as ECG and respiratory bellow. The difference between the two methods is not significant and can be explained. Furthermore, few ECG trigger errors appear in some subjects while these errors are not found in self-gating signals.
文摘9月22日,索尼中国专业系统集团在北京AIT索尼影像技术学院隆重举行Cine Alta V电影摄影机发布会,作为索尼Cine Alta摄影机系统的新一代产品,同时也是影视行业的第一款采用全画幅CMOS（36.2×24.1mm）的摄影机,Cine Alta V面世的消息自9月发布以来便引发了影视行业用户持续的关注和讨论。发布会上,索尼专家和产品经理详解其性能优势、研发背景和多项突破性的＂业界第一＂,并与媒体、业界用户以现场问答、网络直播的方式进行互动,力求全面、精确、
基金supported by the National Natural Science Foundation of China(Grant Nos.81501463,61671026,81571669,and 81671853)the Natural Science Foundation of Guangdong Province,China(Grant No.2014A030310360)+3 种基金Guangdong Innovative Research Team Program of China(Grant No.2011S013)the Basic Research Project of Shenzhen City,China(Grant Nos.JCYJ20140417113430639 and JCYJ20160429172357751)the High-level Oversea Talent Program of Shenzhen City,China(Grant No.KQJSCX20160301144248)Beijing Center for Mathematics and Information Interdisciplinary Sciences of China
文摘This paper presents a nonlinear profile order scheme for three-dimensional（3D） hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging（MRI）. In self-gated, free-breathing cardiac cine MRI,respiratory and cardiac motions are unpredictable during acquisition, especially for retrospective reconstruction. Therefore,the non-uniformity of the k-space distribution is an issue of great concern during retrospective self-gated reconstruction. A nonlinear profile order with varying azimuthal increments was provided and compared with the existing golden ratio-based profile order. Optimal parameter values for the nonlinear formula were chosen based on simulations. The two profile orders were compared in terms of the k-space distribution and phantom and human image results. An approximately uniform distribution was obtained based on the nonlinear profile order for persons with various heart rates and breathing patterns.The nonlinear profile order provides more stable profile distributions and fewer streaking artifacts in phantom images. In a comparison of human cardiac cine images, the nonlinear profile order provided results comparable to those provided by the golden ratio-based profile order, and the images were suitable for diagnosis. In conclusion, the nonlinear profile order scheme was demonstrated to be insensitive to various motion patterns and more useful for retrospective reconstruction.
文摘2006年8月16日，柯达数字影院公司（Kodak Digital Cinema）宣布该公司已经与美国国家影院媒体公司（NCM—National Cine Media）达成协议，联合开发下一代数字影院管理系统（TMS）。这套新的开放式设计的影院管理系统将整合现有的放映设备、管理系统和来自其它厂商的数字影院系统部件。
文摘2月27日,影视行业从业者与爱好者们齐聚北京,共同参与了“Blackmagic URSA Cine 12K电影摄影机工作坊”活动。此次活动为大家提供了深入了解Blackmagic URSA Cine 12K电影摄影机以及交流分享的机会,参与者积极体验,交流氛围热烈。活动伊始,Blackmagic Design中国区总经理曹晨辉对品牌进行了基本介绍(如图1)。
