针对蔡司快速超高分辨激光共聚焦显微镜(LSM 900 with Airyscan2)的成像性能优化问题,该研究系统探究了激光功率、探测器增益、像素驻留时间、平均采样次数及Airyscan成像模式选择等关键参数对分辨率、信噪比(SNR)及成像速度的协同影响...针对蔡司快速超高分辨激光共聚焦显微镜(LSM 900 with Airyscan2)的成像性能优化问题,该研究系统探究了激光功率、探测器增益、像素驻留时间、平均采样次数及Airyscan成像模式选择等关键参数对分辨率、信噪比(SNR)及成像速度的协同影响。通过设计多组对比实验,量化了不同参数组合下的成像性能指标,提出了一套兼顾高分辨率、高信噪比与快速成像的优化策略。结果显示,在Airyscan SR模式下,通过平衡激光功率(0.1%~50%)、探测器增益(550~850 V)及像素驻留时间(0.5~4.0μs)、平均采样次数(0~8次),可实现xy方向分辨率≤120 nm。该研究为超分辨成像参数优化提供了可操作的参数优化框架,对生物医学超分辨成像研究具有重要参考价值。展开更多
Seismic wave propagation in fluid-solid coupled media is currently a popular topic. However, traditional wave equation-based simulation methods have to consider complex boundary conditions at the fluid-solid interface...Seismic wave propagation in fluid-solid coupled media is currently a popular topic. However, traditional wave equation-based simulation methods have to consider complex boundary conditions at the fluid-solid interface. To address this challenge, we propose a novel numerical scheme that integrates the lattice Boltzmann method(LBM) and lattice spring model(LSM). In this scheme, LBM simulates viscoacoustic wave propagation in the fluid area and LSM simulates elastic wave propagation in the solid area. We also introduce three different LBM-LSM coupling strategies, a standard bounce back scheme, a specular reflection scheme, and a hybrid scheme, to describe wave propagation across fluid-solid boundaries. To demonstrate the accuracy of these LBM-LSM coupling schemes, we simulate wave propagation in a two-layer model containing a fluid-solid interface. We place excitation sources in the fluid layer and the solid layer respectively, to observe the wave phenomena when seismic waves propagate to interface from different sides. The simulated results by LBM-LSM are compared with the reference wavefields obtained by the finite difference method(FDM) and the analytical solution(ANA).Our LBM-LSM coupling scheme was verified effective, as the relative errors between the LBM-LSM solutions and reference solutions were within an acceptable range, sometimes around 1.00%. The coupled LBM-LSM scheme is further used to model seismic wavefields across a more realistic rugged seabed,which reveals the potential applications of the coupled LBM-LSM scheme in marine seismic imaging techniques, such as reverse-time migration and full-waveform inversion. The method also has potential applications in simulating wave propagation in complex two-and multi-phase media.展开更多
The generation of mature and healthy oocytes is the most critical event in the entire female reproductive process,and the mechanisms regulating this process remain to be studied.Here,we demonstrate that Smith-like(LSM...The generation of mature and healthy oocytes is the most critical event in the entire female reproductive process,and the mechanisms regulating this process remain to be studied.Here,we demonstrate that Smith-like(LSM)family member 14B(LSM14B)regulates oocyte maturation,and the loss of LSM14B in mouse ovaries leads to abnormal oocyte MII arrest and female infertility.Next,we find the aberrant transcriptional activation,indicated by abnormal non-surrounded nucleolus and surrounded nucleolus oocyte proportions,and abnormal chromosome assembly and segregation in Lsm14b-deficient mouse oocytes.The global transcriptome analysis suggests that many transcripts involved in cytoplasmic processing body(P-body)function are altered in Lsm14b-deficient mouse oocytes.Deletion of Lsm14b results in the expression and/or localization changes of P-body components(such as LSM14A,DCP1A,and 4E-T).Notably,DDX6,a key component of the P-body,is downregulated and accumulates in the nuclei in Lsm14b-deficient mouse oocytes.Taken together,our data suggest that LSM14B links mouse oocyte maturation to female fertility through the regulation of the P-body.展开更多
The adoption of Docker containers has revolutionized software deployment by providing a lightweight and efficient way to isolate applications in data centers. However, securing these containers, especially when handli...The adoption of Docker containers has revolutionized software deployment by providing a lightweight and efficient way to isolate applications in data centers. However, securing these containers, especially when handling sensitive data, poses significant challenges. Traditional Linux Security Modules (LSMs) such as SELinux and AppArmor have limitations in providing fine-grained access control to files within containers. This paper presents a novel approach using eBPF (extended Berkeley Packet Filter) to implement a LSM that focuses on file-oriented access control within Docker containers. The module allows the specification of policies that determine which programs can access sensitive files, providing enhanced security without relying solely on the host operating system’s major LSM.展开更多
针对最小二乘法(Least Squares Method,LSM)对于超宽带(Ultra Wide Band,UWB)中飞行时间(Time of Flight,TOF)法在非视距(Non Line of Sight,NLoS)下定位精度低下的问题,提出了基于扩展灰狼算法(Extended Gray Wolf Algorithm,EGWO)优...针对最小二乘法(Least Squares Method,LSM)对于超宽带(Ultra Wide Band,UWB)中飞行时间(Time of Flight,TOF)法在非视距(Non Line of Sight,NLoS)下定位精度低下的问题,提出了基于扩展灰狼算法(Extended Gray Wolf Algorithm,EGWO)优化后的长短期记忆(Long Short-Term Memory,LSTM)网络改进LSM定位算法(EGWO-LSTM-LSM)。采用LSTM及改进的EGWO建立最优测距误差预测模型,根据预测结果构造权重矩阵,在LSM上加权计算,并添加测距误差校正项,以改进LSM实现静态定位,并结合卡尔曼滤波器(Kalman Filter,KF)实现动态定位追踪。仿真结果表明,EGWO-LSTM预测准确率达98.857%,EGWO-LSTM-LSM将二维和三维位置误差分别稳定控制在10~25 mm,进一步提升了TOF定位精度。展开更多
基金supported in part by R & D Department of China National Petroleum Corporation (2022DQ0604-01)National Natural Science Foundation of China (42204132)+3 种基金the China Postdoctoral Science Foundations (2020M680667, 2021T140661)Harvard-CUP Joint Laboratory on Petroleum Science“111” project (B13010)the financial support from the CAS Special Research Assistant Project。
文摘Seismic wave propagation in fluid-solid coupled media is currently a popular topic. However, traditional wave equation-based simulation methods have to consider complex boundary conditions at the fluid-solid interface. To address this challenge, we propose a novel numerical scheme that integrates the lattice Boltzmann method(LBM) and lattice spring model(LSM). In this scheme, LBM simulates viscoacoustic wave propagation in the fluid area and LSM simulates elastic wave propagation in the solid area. We also introduce three different LBM-LSM coupling strategies, a standard bounce back scheme, a specular reflection scheme, and a hybrid scheme, to describe wave propagation across fluid-solid boundaries. To demonstrate the accuracy of these LBM-LSM coupling schemes, we simulate wave propagation in a two-layer model containing a fluid-solid interface. We place excitation sources in the fluid layer and the solid layer respectively, to observe the wave phenomena when seismic waves propagate to interface from different sides. The simulated results by LBM-LSM are compared with the reference wavefields obtained by the finite difference method(FDM) and the analytical solution(ANA).Our LBM-LSM coupling scheme was verified effective, as the relative errors between the LBM-LSM solutions and reference solutions were within an acceptable range, sometimes around 1.00%. The coupled LBM-LSM scheme is further used to model seismic wavefields across a more realistic rugged seabed,which reveals the potential applications of the coupled LBM-LSM scheme in marine seismic imaging techniques, such as reverse-time migration and full-waveform inversion. The method also has potential applications in simulating wave propagation in complex two-and multi-phase media.
基金supported by the National Key R&D Program of China(2021YFC2700201 to X.W.)the National Natural Science Foundation of China(32070831,32270897 to X.W.).
文摘The generation of mature and healthy oocytes is the most critical event in the entire female reproductive process,and the mechanisms regulating this process remain to be studied.Here,we demonstrate that Smith-like(LSM)family member 14B(LSM14B)regulates oocyte maturation,and the loss of LSM14B in mouse ovaries leads to abnormal oocyte MII arrest and female infertility.Next,we find the aberrant transcriptional activation,indicated by abnormal non-surrounded nucleolus and surrounded nucleolus oocyte proportions,and abnormal chromosome assembly and segregation in Lsm14b-deficient mouse oocytes.The global transcriptome analysis suggests that many transcripts involved in cytoplasmic processing body(P-body)function are altered in Lsm14b-deficient mouse oocytes.Deletion of Lsm14b results in the expression and/or localization changes of P-body components(such as LSM14A,DCP1A,and 4E-T).Notably,DDX6,a key component of the P-body,is downregulated and accumulates in the nuclei in Lsm14b-deficient mouse oocytes.Taken together,our data suggest that LSM14B links mouse oocyte maturation to female fertility through the regulation of the P-body.
文摘The adoption of Docker containers has revolutionized software deployment by providing a lightweight and efficient way to isolate applications in data centers. However, securing these containers, especially when handling sensitive data, poses significant challenges. Traditional Linux Security Modules (LSMs) such as SELinux and AppArmor have limitations in providing fine-grained access control to files within containers. This paper presents a novel approach using eBPF (extended Berkeley Packet Filter) to implement a LSM that focuses on file-oriented access control within Docker containers. The module allows the specification of policies that determine which programs can access sensitive files, providing enhanced security without relying solely on the host operating system’s major LSM.
文摘针对最小二乘法(Least Squares Method,LSM)对于超宽带(Ultra Wide Band,UWB)中飞行时间(Time of Flight,TOF)法在非视距(Non Line of Sight,NLoS)下定位精度低下的问题,提出了基于扩展灰狼算法(Extended Gray Wolf Algorithm,EGWO)优化后的长短期记忆(Long Short-Term Memory,LSTM)网络改进LSM定位算法(EGWO-LSTM-LSM)。采用LSTM及改进的EGWO建立最优测距误差预测模型,根据预测结果构造权重矩阵,在LSM上加权计算,并添加测距误差校正项,以改进LSM实现静态定位,并结合卡尔曼滤波器(Kalman Filter,KF)实现动态定位追踪。仿真结果表明,EGWO-LSTM预测准确率达98.857%,EGWO-LSTM-LSM将二维和三维位置误差分别稳定控制在10~25 mm,进一步提升了TOF定位精度。
