基于梯度结构的星载红外图像和全色图像配准方法

针对红外图像与全色图像的不同的成像特性,提出了一种基于图像的梯度结构信息的匹配算法.首先对原始的红外和全色图像分别进行梯度计算,得到图像的梯度强度图;对梯度图进行结构相似性度量,获得图像间同名点对.然后采用RANSAC算法剔除误匹配的同名点.最后利用同名点对构建三角网小面元,并进行变换而得到配准图像.实验结果表明,算法可以有效地利用红外图像中地物的结构信息,匹配精度高.     

基于CNN-WF的高灵敏紫外成像仪中的图像配准与融合

针对现有紫外成像仪中紫外光与可见光图像配准实时性差,精度不高等问题,提出一种基于卷积神经网络(Convolutional Neural Networks,CNN)与小波融合(Wavelet Fusion,WF)的紫外光与可见光图像配准融合方法,并将其应用于高灵敏紫外成像仪中.首先,结合刚体变换和卷积神经网络对采集到的图像数据进行参数模型预训练,通过自主挖掘图像特征寻找到最优空间变换参数,实现紫外光图像与可见光图像的精确配准;其次,利用二维小波分解与重构算法实现紫外光与可见光图像的融合.实验结果表明,所提方法的紫外光图像与可见光图像配准速度快,叠加精度高,且具有良好的稳定性.     

A Bio-Conjugated Fullerene as a Subcellular-Targeted and Multifaceted Phototheranostic Agent

Fullerenes are candidates for theranostic applications because of their high photodynamic activity and intrinsic multimodal imaging contrast. However, fullerenes suffer from low solubility in aqueous media, poor biocompatibility, cell toxicity, and a tendency to aggregate. C₇₀@lysozyme is introduced herein as a novel bioconjugate that is harmless to a cellular environment, yet is also photoactive and has excellent optical and optoacoustic contrast for tracking cellular uptake and intracellular localization. The formation, water-solubility, photoactivity, and unperturbed structure of C₇₀@lysozyme are confirmed using UV-visible and 2D ¹H, ¹⁵N NMR spectroscopy. The excellent imaging contrast of C₇₀@lysozyme in optoacoustic and third harmonic generation microscopy is exploited to monitor its uptake in HeLa cells and lysosomal trafficking. Last, the photoactivity of C₇₀@lysozyme and its ability to initiate cell death by means of singlet oxygen (¹O₂) production upon exposure to low levels of white light irradiation is demonstrated. This study introduces C₇₀@lysozyme and other fullerene-protein conjugates as potential candidates for theranostic applications.     

High‐Efficient Clearable Nanoparticles for Multi‐Modal Imaging and Image‐Guided Cancer Therapy

Renal‐clearable nanoparticles have made it possible to overcome the toxicity by nonspecific accumulation in healthy tissues/organs due to their highly efficient clearance characteristics. However, their tumor uptake is relatively low due to the short blood circulation time and rapid body elimination. Here, this problem is addressed by developing renal‐clearable nanoparticles by controlled coating of sub‐6 nm CuS nanodots (CuSNDs) on doxorubicin ladened mesoporous silica nanoparticles (pore size ≈6 nm) for multimodal application. High tumor uptake of the as‐synthesized nanoparticles (abbreviated as MDNs) is achieved due to the longer blood circulation time. The MDNs also show excellent performance in bimodal imaging. Moreover, the MDNs demonstrated a photothermally sensitive drug release and pronounced synergetic effects of chemo‐photothermal therapy, which were confirmed by two different tumor models in vivo. A novel key feature of the proposed synthesis is the use of renal‐clearable CuSNDs and biodegradable mesoporous silica nanoparticles which also are renal‐clearable after degradation. Therefore, the MDNs would be rapidly degraded and excreted in a reasonable period in living body and avoid long‐term toxicity. Such biodegradable and clearable single‐compartment theranostic agents applicable in highly integrated multimodal imaging and multiple therapeutic functions may have substantial potentials in clinical practice.     

AI虚拟数字人技术在融合媒体生产中的运用

重大活动无线电安全保障肩负着贯彻国家安全战略,维护社会稳定,维护国家形象的重要使命。通过对重大活动无线电安全保障工作内容的梳理,深化对无线电保障工作的认识,更好地服务于今后的重大活动无线电保障工作。     

Petromyzontidae-Biomimetic Multimodal Microneedles-Integrated Bioelectronic Catheters for Theranostic Endoscopic Surgery

Current catheter devices in minimally invasive surgery still possess limited functional options, lacking multimodal integration of both sensing and therapy. Catheter devices usually operate outside the tissue, incapable to detect intra-tissue biochemical information for accurate localization and assessment of lesions during surgery. Inspired by the feature and functions of Petromyzontidae, here a multimodal core-shell microneedles-integrated bioelectronic catheter (MNIBC) for tissue-penetrating theranostics in endoscopic surgery is developed. The microneedle (MN) device possesses individually addressable functionality at single-MN tip resolution, enabling multiplex functions (a total of 11 functions distributed in three types of catheters) including biochemical sensing, myoelectric modulation, electroporation, and drug delivery in a submucosal environment. The MNIBC is prepared through hybrid fabrication and dimensionality reduction strategies, where the MN electrodes are functionalized with an MXene-carbon nanotube (MXene-CNT)-based electron mediator, addressing the challenge of reduced electrode sensitivity on ultra-small MN tip. The functionalities of MNIBC are demonstrated both ex vivo and in vivo on anesthetized rabbits via laparoscopy, simulated cystoscopy, and laparotomy. The MNIBC can effectively detect intra-tissue biochemical signals in the bladder, and offers localized electroporation and intra-tissue drug delivery for precise treatments of lesions. The versatile features of the MNIBC present a highly advanced platform for precise surgeries.     

实时时间配准仿真研究

针对多传感器数据融合系统中观测数据时间不同步的问题,采用常系数滤波算法与Lagrange插值法结合进行时间配准,并用仿真的方法验证了此配准方法有效。与现有算法比较,此方法可与目标跟踪同步进行,配准实时性强,且简单,可提高融合效率。     

Compact support Thin Plate Spline algorithm

Common tools based on landmarks in medical image elastic registration are Thin Plate Spline (TPS) and Compact Support Radial Basis Function (CSRBF). TPS forces the corresponding landmarks to exactly match each other and minimizes the bending energy of the whole image. However, in real application, such scheme would deform the image globally when deformation is only local. CSRBF needs manually determine the support size, although its deformation is limited local. Therefore, to limit the effect of the deformation, new Compact Support Thin Plate Spline algorithm (CSTPS) is approached, analyzed and applied. Such new approach gains optimal mutual information, which shows its registration result satisfactory. The experiments also show it can apply in both local and global elastic registration.     

无人机多光谱成像仪图像的校正及配准算法研究

利用光校参数和软件配准法对无人机多光谱成像仪图像进行校正和彩色合成.多光谱成像仪由3个光电头部组成,它们分别对同一地物的R、G、B谱段成像.基于无人机多光谱成像仪中各光谱段成像光电头部存在的性能差异,需要进行图像配准,才能保证图像合成的效果.具体分析与讨论光校参数法与软件配准法的特点,采用这两种方法进行图像配准,并在此基础上提出采用二者相结合的手段研究进一步的算法,以期达到更好的配准效果.     

基于K-L变换的两传感器图像自动配准

基于合成孔径雷达(SAR)图像和光学图像间的变形可用仿射变换来近似,提出了一种SAR图像和光学图像自动配准的方案.对分割后的图像进行K-L变换得到两幅图像的主分量与坐标轴之间的关系,从而得出两幅图像的角度关系,接着,利用旋转后图像的横纵象素范围的比值和前景重心偏移值得到仿射变换的缩放和平移参数,最后再利用二值图像相关对仿射变换的结果图像进行精配,从而实现较高精度的图像配准.实验结果表明,在满足精度要求的情况下,本方法可以自动完成具有明显方向性和较大前景目标图像的配准任务.