Transformer has achieved impressive successes for various computer vision tasks. However, most of existing studies require to pretrain the Transformer backbone on a large-scale labeled dataset (e.g., ImageNet) for achieving satisfactory performance, which is usually unavailable for medical images. Additionally, due to the gap between medical and natural images, the improvement generated by the ImageNet pretrained weights significantly degrades while transferring the weights to medical image processing tasks. In this paper, we propose Bootstrap Own Latent of Transformer (BOLT), a self-supervised learning approach specifically for medical image classification with the Transformer backbone. Our BOLT consists of two networks, namely online and target branches, for self-supervised representation learning. Concretely, the online network is trained to predict the target network representation of the same patch embedding tokens with a different perturbation. To maximally excavate the impact of Transformer from limited medical data, we propose an auxiliary difficulty ranking task. The Transformer is enforced to identify which branch (i.e., online/target) is processing the more difficult perturbed tokens. Overall, the Transformer endeavours itself to distill the transformation-invariant features from the perturbed tokens to simultaneously achieve difficulty measurement and maintain the consistency of self-supervised representations. The proposed BOLT is evaluated on three medical image processing tasks, i.e., skin lesion classification, knee fatigue fracture grading and diabetic retinopathy grading. The experimental results validate the superiority of our BOLT for medical image classification, compared to ImageNet pretrained weights and state-of-the-art self-supervised learning approaches.

During X-ray computed tomography (CT) scanning, metallic implants carrying with patients often lead to adverse artifacts in the captured CT images and then impair the clinical treatment. Against this metal artifact reduction (MAR) task, the existing deep-learning-based methods have gained promising reconstruction performance. Nevertheless, there is still some room for further improvement of MAR performance and generalization ability, since some important prior knowledge underlying this specific task has not been fully exploited. Hereby, in this paper, we carefully analyze the characteristics of metal artifacts and propose an orientation-shared convolution representation strategy to adapt the physical prior structures of artifacts, i.e., rotationally symmetrical streaking patterns. The proposed method rationally adopts Fourier-series-expansion-based filter parametrization in artifact modeling, which can better separate artifacts from anatomical tissues and boost the model generalizability. Comprehensive experiments executed on synthesized and clinical datasets show the superiority of our method in detail preservation beyond the current representative MAR methods. Code will be available at \url{https://github.com/hongwang01/OSCNet}

Multi-view graph clustering (MGC) methods are increasingly being studied due to the explosion of multi-view data with graph structural information. The critical point of MGC is to better utilize the view-specific and view-common information in features and graphs of multiple views. However, existing works have an inherent limitation that they are unable to concurrently utilize the consensus graph information across multiple graphs and the view-specific feature information. To address this issue, we propose Variational Graph Generator for Multi-View Graph Clustering (VGMGC). Specifically, a novel variational graph generator is proposed to extract common information among multiple graphs. This generator infers a reliable variational consensus graph based on a priori assumption over multiple graphs. Then a simple yet effective graph encoder in conjunction with the multi-view clustering objective is presented to learn the desired graph embeddings for clustering, which embeds the inferred view-common graph and view-specific graphs together with features. Finally, theoretical results illustrate the rationality of VGMGC by analyzing the uncertainty of the inferred consensus graph with information bottleneck principle. Extensive experiments demonstrate the superior performance of our VGMGC over SOTAs.

胸部X射线（CXR）中准确的异常定位可以使各种胸部疾病的临床诊断受益。但是，病变水平的注释只能由经验丰富的放射科医生进行，这是乏味且耗时的，因此很难获得。这种情况导致难以开发CXR的完全监督异常定位系统。在这方面，我们建议通过一个弱半监督的策略来训练CXR异常本地化框架，称为“超越阶级”（PBC），该策略（PBC）使用了少数带有病变级别边界框的完全注释的CXR，并通过广泛的弱化的样品和大量的带有注释的样品。点。这样的点注释设置可以通过边缘注释成本提供弱实例级信息，以实现异常定位。尤其是，我们的PBC背后的核心思想是学习从点注释到边界框的强大而准确的映射，以根据注释点的差异。为此，提出了一个正则化项，即多点的一致性，它驱动模型从相同异常内的不同点注释中生成一致的边界框。此外，还提出了一种被称为对称的一致性的自学，也提出了从弱注释的数据中深入利用有用的信息来实现异常定位。 RSNA和VINDR-CXR数据集的实验结果证明了该方法的有效性。当使用少于20％的盒子级标签进行训练时，与当前的最新方法相比，我们的PBC可以在MAP中提高〜5的改进（即点DETR）。代码可从https://github.com/haozheliu-st/point-beyond-class获得。

近年来，生成的对抗网络（GAN）在各种任务和应用中都显示出了令人信服的结果。但是，模式崩溃仍然是gan的关键问题。在本文中，我们提出了一条新型的培训管道，以解决甘恩斯的模式崩溃问题。与现有方法不同，我们建议将鉴别器概括为特征嵌入，并最大程度地提高鉴别器学到的嵌入空间中分布的熵。具体而言，两个正则化术语，即深度局部线性嵌入（DLLE）和深度等距特征映射（疾病），旨在鼓励歧视者学习嵌​​入数据中的结构信息，以便可以是歧视器所学的嵌入空间，可以是可以得到的。形成良好。基于鉴别器支持的良好学习嵌入空间，非参数熵估计量旨在有效地最大化嵌入向量的熵，以最大化生成分布的熵的近似值。通过改善鉴别器并最大化嵌入空间中最相似的样品的距离，我们的管道可有效地减少模式崩溃的情况，而无需牺牲生成的样品的质量。广泛的实验结果表明，我们的方法的有效性超过了GAN基线，MAF-GAN在Celeba上（9.13 vs. 12.43），超过了最新的基于动漫的能量模型（Anime-Face DataSet（ 2.80 vs. 2.26的成立得分）。

沟通效率在加速深神经网络（DNN）的分布式训练中起着重要作用。 All-Reduce是减少分布式DNN培训中模型参数的关键沟通原始性。大多数现有的全减少算法都是为传统的电气互连系统设计的，该系统无法满足大型DNN分布式培训的通信要求。电气互连的有希望的替代方案之一是光学互连，可以提供高带宽，低传输延迟和低功率成本。我们提出了一个称为WRHT（波长重复使用的层次树）的有效方案，用于在光学互连系统中实现全降压操作，该系统可以利用WDM（波长多路复用）来减少分布式数据 - 偏置DNN训练的通信时间。我们进一步得出了最少的通信步骤和通信时间，以实现使用WRHT的全面减少。仿真结果表明，与在光学互连系统中模拟的三种传统的全减少算法相比，WRHT的通信时间分别减少了75.59％，49.25％和70.1％。仿真结果还表明，与电气互连系统中的两种现有的全减速算法相比，WRHT可以将所有还原操作的通信时间减少86.69％和84.71％。

从磁共振成像（MRI）中进行精确的脑肿瘤分割，对于多模式图像的联合学习是可取的。但是，在临床实践中，并非总是有可能获得一组完整的MRI，而缺失模态的问题会导致现有的多模式分割方法中的严重性能降解。在这项工作中，我们提出了第一次尝试利用变压器进行多模式脑肿瘤分割的尝试，该脑肿瘤分割对任何可用模式的任何组合子集都是可靠的。具体而言，我们提出了一种新型的多模式医疗变压器（MMMFORMER），用于不完整的多模式学习，具有三个主要成分：混合模态特异性的编码器，该编码器在每种模式中桥接卷积编码器和一个局部和全局上下文模型的模式内变压器；一种模式间变压器，用于建立和对齐模态跨模态的远程相关性，以对应于肿瘤区域的全局语义。一个解码器，与模态不变特征进行渐进的上采样和融合，以生成可靠的分割。此外，在编码器和解码器中都引入了辅助正规化器，以进一步增强模型对不完整方式的鲁棒性。我们对公共批评的大量实验$ 2018 $ $数据集用于脑肿瘤细分。结果表明，所提出的MMFORMER优于几乎所有不完整模态的亚群的多模式脑肿瘤分割的最新方法，尤其是在肿瘤分割的平均骰子中平均提高了19.07％，只有一种可用的模式。该代码可在https://github.com/yaozhang93/mmmenforer上找到。

The existence of completely aligned and paired multi-modal neuroimaging data has proved its effectiveness in diagnosis of brain diseases. However, collecting the full set of well-aligned and paired data is expensive or even impractical, since the practical difficulties may include high cost, long time acquisition, image corruption, and privacy issues. A realistic solution is to explore either an unsupervised learning or a semi-supervised learning to synthesize the absent neuroimaging data. In this paper, we are the first one to comprehensively approach cross-modality neuroimage synthesis task from different perspectives, which include the level of the supervision (especially for weakly-supervised and unsupervised), loss function, evaluation metrics, the range of modality synthesis, datasets (aligned, private and public) and the synthesis-based downstream tasks. To begin with, we highlight several opening challenges for cross-modality neuroimage sysnthesis. Then we summarize the architecture of cross-modality synthesis under various of supervision level. In addition, we provide in-depth analysis of how cross-modality neuroimage synthesis can improve the performance of different downstream tasks. Finally, we re-evaluate the open challenges and point out the future directions for the remaining challenges. All resources are available at https://github.com/M-3LAB/awesome-multimodal-brain-image-systhesis

完全排列和配对的多模式神经成像数据的存在证明了其在诊断脑疾病中的有效性。但是，收集完整的一组良好的配对数据是不切实际的，因为实际困难可能包括高成本，长期获取，图像腐败和隐私问题。以前，未配对的神经影像数据（称为泥）通常被视为嘈杂的标签。但是，这种基于嘈杂的标签的方法在严重发生扭曲的数据时无法完成。例如，旋转角度不同。在本文中，我们提出了一种新的联邦自制学习（FEDMED），以用于脑形象合成。制定了仿射变换损失（ATL），以利用严重扭曲的图像，而无需违反医院的隐私立法。然后，我们引入了一种新的数据增强程序，以进行自我监督训练，并将其送入三个辅助头，即辅助旋转，辅助翻译和辅助缩放头。所提出的方法证明了在严重错误和未配对的数据设置下，我们合成结果的质量的高级性能，并且比其他基于GAN的算法更好。提出的方法还减少了对可变形注册的需求，同时鼓励利用未对准和未配对的数据。与其他最先进的方法相比，实验结果验证了我们学习范式的出色表现。

半监督学习是一个具有挑战性的问题，旨在通过从有限标记的例子学习来构建模型。此任务的许多方法侧重于利用单独的未标记实例的预测，以单独进行正规化网络。然而，分别处理标记和未标记的数据通常导致从标记的例子中学习的质量事先知识的丢弃。 ％，并且未能在标记和未标记的图像对之间的特征交互。在本文中，我们提出了一种新的半监督语义细分方法，名为Guidedmix-Net，通过利用标签信息来指导未标记的实例的学习。具体而言，Guidedmix-Net采用三种操作：1）类似标记的未标记图像对的插值; 2）转让互动信息; 3）伪面具的概括。它使分段模型可以通过将知识从标记的样本转移到未标记的数据来学习未标记数据的更高质量的伪掩模。除了用于标记数据的监督学习之外，使用来自混合数据的生成的伪掩模共同学习未标记数据的预测。对Pascal VOC的大量实验2012年，城市景观展示了我们的Guidedmix-Net的有效性，这实现了竞争性的细分准确性，并与以前的方法相比，通过+7美元\％$大大改善Miou。