Late-life depression (LLD) is a highly prevalent mood disorder occurring in older adults and is frequently accompanied by cognitive impairment (CI). Studies have shown that LLD may increase the risk of Alzheimer's disease (AD). However, the heterogeneity of presentation of geriatric depression suggests that multiple biological mechanisms may underlie it. Current biological research on LLD progression incorporates machine learning that combines neuroimaging data with clinical observations. There are few studies on incident cognitive diagnostic outcomes in LLD based on structural MRI (sMRI). In this paper, we describe the development of a hybrid representation learning (HRL) framework for predicting cognitive diagnosis over 5 years based on T1-weighted sMRI data. Specifically, we first extract prediction-oriented MRI features via a deep neural network, and then integrate them with handcrafted MRI features via a Transformer encoder for cognitive diagnosis prediction. Two tasks are investigated in this work, including (1) identifying cognitively normal subjects with LLD and never-depressed older healthy subjects, and (2) identifying LLD subjects who developed CI (or even AD) and those who stayed cognitively normal over five years. To the best of our knowledge, this is among the first attempts to study the complex heterogeneous progression of LLD based on task-oriented and handcrafted MRI features. We validate the proposed HRL on 294 subjects with T1-weighted MRIs from two clinically harmonized studies. Experimental results suggest that the HRL outperforms several classical machine learning and state-of-the-art deep learning methods in LLD identification and prediction tasks.

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

Non-Pharmaceutical Interventions (NPIs), such as social gathering restrictions, have shown effectiveness to slow the transmission of COVID-19 by reducing the contact of people. To support policy-makers, multiple studies have first modeled human mobility via macro indicators (e.g., average daily travel distance) and then studied the effectiveness of NPIs. In this work, we focus on mobility modeling and, from a micro perspective, aim to predict locations that will be visited by COVID-19 cases. Since NPIs generally cause economic and societal loss, such a micro perspective prediction benefits governments when they design and evaluate them. However, in real-world situations, strict privacy data protection regulations result in severe data sparsity problems (i.e., limited case and location information). To address these challenges, we formulate the micro perspective mobility modeling into computing the relevance score between a diffusion and a location, conditional on a geometric graph. we propose a model named Deep Graph Diffusion Infomax (DGDI), which jointly models variables including a geometric graph, a set of diffusions and a set of locations.To facilitate the research of COVID-19 prediction, we present two benchmarks that contain geometric graphs and location histories of COVID-19 cases. Extensive experiments on the two benchmarks show that DGDI significantly outperforms other competing methods.

没有标签的预处理分子表示模型是各种应用的基础。常规方法主要是处理2D分子图，并仅专注于2D任务，使其预验证的模型无法表征3D几何形状，因此对于下游3D任务有缺陷。在这项工作中，我们从完整而新颖的意义上处理了3D分子预处理。特别是，我们首先提议采用基于能量的模型作为预处理的骨干，该模型具有实现3D空间对称性的优点。然后，我们为力预测开发了节点级预处理损失，在此过程中，我们进一步利用了Riemann-Gaussian分布，以确保损失为E（3） - 不变，从而实现了更多的稳健性。此外，还利用了图形噪声量表预测任务，以进一步促进最终的性能。我们评估了从两个具有挑战性的3D基准：MD17和QM9的大规模3D数据集GEOM-QM9预测的模型。实验结果支持我们方法对当前最新预处理方法的更好疗效，并验证我们设计的有效性。

图对比度学习已被证明是图形神经网络（GNN）预训练的有效任务。但是，一个关键问题可能会严重阻碍现有作品中的代表权：当前方法创建的积极实例通常会错过图表的关键信息，甚至会错过非法实例（例如分子生成中的非化学意识图）。为了解决此问题，我们建议直接从训练集中的现有图中选择正图实例，该实例最终保持与目标图的合法性和相似性。我们的选择基于某些特定于域的成对相似性测量以及从层次图编码图中的相似性关系的采样。此外，我们开发了一种自适应节点级预训练方法，以动态掩盖节点在图中均匀分布。我们对来自各个域的$ 13 $图形分类和节点分类基准数据集进行了广泛的实验。结果表明，通过我们的策略预先培训的GNN模型可以胜过那些训练有素的从划痕模型以及通过现有方法获得的变体。

节点分类和图形分类是两个图形学习问题，分别预测节点的类标签和图形的类标签。图的节点通常代表现实世界实体，例如，社交网络中的用户或文档引用网络中的文档。在这项工作中，我们考虑了一个更具挑战性但实际上有用的设置，其中节点本身是图形实例。这导致了层次图的观点，该视角在许多领域（例如社交网络，生物网络和文档收集）中产生。我们在层次图中研究节点分类问题，其中“节点”是图形实例。由于标签通常受到限制，我们设计了一种新型的半监督溶液，名为Seal-CI。 Seal-CI采用了一个迭代框架，该框架需要轮流更新两个模块，一个模块在图形实例级别，另一个在层次图级别上进行。为了在不同级别的层次图之间执行一致性，我们提出了分层图共同信息（HGMI），并进一步提出了一种使用理论保证计算HGMI的方法。我们证明了该层次图建模的有效性以及在文本和社交网络数据上提出的密封CI方法。

语言模型既展示了定量的改进，又展示了新的定性功能，随着规模的增加。尽管它们具有潜在的变革性影响，但这些新能力的特征却很差。为了为未来的研究提供信息，为破坏性的新模型能力做准备，并改善社会有害的效果，至关重要的是，我们必须了解目前和近乎未来的能力和语言模型的局限性。为了应对这一挑战，我们介绍了超越模仿游戏基准（Big Bench）。 Big Bench目前由204个任务组成，由132家机构的442位作者贡献。任务主题是多样的，从语言学，儿童发展，数学，常识性推理，生物学，物理学，社会偏见，软件开发等等。 Big-Bench专注于被认为超出当前语言模型的功能的任务。我们评估了OpenAI的GPT型号，Google内部密集变压器体系结构和大型基础上的开关稀疏变压器的行为，跨越了数百万到数十亿个参数。此外，一个人类专家评估者团队执行了所有任务，以提供强大的基准。研究结果包括：模型性能和校准都随规模改善，但绝对的术语（以及与评估者的性能相比）；在模型类中的性能非常相似，尽管带有稀疏性。逐渐和预测的任务通常涉及大量知识或记忆成分，而在临界规模上表现出“突破性”行为的任务通常涉及多个步骤或组成部分或脆性指标；社交偏见通常会随着含糊不清的环境而随着规模而增加，但这可以通过提示来改善。

结构重新参数化（REP）方法已在传统的卷积网络上取得了重大的性能提高。大多数当前的REP方法依靠先验知识来选择重新聚集操作。但是，体系结构的性能受到操作类型和先验知识的限制。为了打破这项限制，在这项工作中，设计了改进的重新参数化搜索空间，其中包括更多类型的重新参数操作。具体而言，搜索空间可以进一步提高卷积网络的性能。为了有效地探索该搜索空间，基于神经体系结构搜索（NAS）设计了自动重新参数增强策略，该策略可以搜索出色的重新参数化体系结构。此外，我们可视化体系结构的输出功能，以分析形成重新参数架构的原因。在公共数据集中，我们取得了更好的结果。在与RESNET相同的训练条件下，我们将Resnet-50的准确性提高了Imagenet-1K的1.82％。

Context-aware decision support in the operating room can foster surgical safety and efficiency by leveraging real-time feedback from surgical workflow analysis. Most existing works recognize surgical activities at a coarse-grained level, such as phases, steps or events, leaving out fine-grained interaction details about the surgical activity; yet those are needed for more helpful AI assistance in the operating room. Recognizing surgical actions as triplets of <instrument, verb, target> combination delivers comprehensive details about the activities taking place in surgical videos. This paper presents CholecTriplet2021: an endoscopic vision challenge organized at MICCAI 2021 for the recognition of surgical action triplets in laparoscopic videos. The challenge granted private access to the large-scale CholecT50 dataset, which is annotated with action triplet information. In this paper, we present the challenge setup and assessment of the state-of-the-art deep learning methods proposed by the participants during the challenge. A total of 4 baseline methods from the challenge organizers and 19 new deep learning algorithms by competing teams are presented to recognize surgical action triplets directly from surgical videos, achieving mean average precision (mAP) ranging from 4.2% to 38.1%. This study also analyzes the significance of the results obtained by the presented approaches, performs a thorough methodological comparison between them, in-depth result analysis, and proposes a novel ensemble method for enhanced recognition. Our analysis shows that surgical workflow analysis is not yet solved, and also highlights interesting directions for future research on fine-grained surgical activity recognition which is of utmost importance for the development of AI in surgery.

由于使用深度学习模型作为基本功能，语音增强（SE）的性能已大大提高。本文中，我们提出了一种感知对比度拉伸（PC）方法，以进一步提高SE性能。 PC是基于临界频带重要性函数得出的，并应用于修改SE模型的目标。具体而言，目标特征的对比是根据感知重要性拉伸的，从而提高了整体SE性能。与基于后处理的实现相比，将PC纳入培训阶段可以保留性能并减少在线计算。值得注意的是，PC可以与不同的SE模型架构和训练标准结合使用。此外，PC不影响SE模型训练的因果关系或收敛性。 VoiceBank按需数据集的实验结果表明，所提出的方法可以在因果关系（PESQ得分= 3.07）和非causal（PESQ分数= 3.35）SE任务上实现最先进的表现。