多实施学习(MIL)被广泛用于对病理整体幻灯片图像(WSIS)的计算机辅助解释,以解决缺乏像素或贴片的注释。通常,这种方法直接应用“自然图像驱动”的MIL算法,该算法忽略了WSIS的多尺度(即金字塔)性质。现成的MIL算法通常部署在单个WSIS(例如20x放大倍率)上,而人类病理学家通常以多尺度的方式汇总全球和局部模式(例如,通过放大不同大型)。在这项研究中,我们提出了一种新型的跨尺度注意机制,以明确地将尺度间相互作用汇总到单个MIL网络的克罗恩病(CD)(CD),这是炎症性肠病的一种形式。本文的贡献是两个方面:(1)提出了一种跨尺度注意机制,以从不同分辨率的多尺度相互作用汇总特征; (2)生成差异多尺度注意的可视化,以定位可解释的病变模式。通过训练来自20名CD患者的约250,000 H&E染色的上升结肠(AC)斑块,在不同尺度上训练30个健康对照样品,我们的方法在曲线下(AUC)得分为0.8924,与基线模型相比达到0.8924。官方实施可在https://github.com/hrlblab/cs-mil上公开获得。
translated by 谷歌翻译
医学图像分割或计算voxelwise语义面具是一个基本又具有挑战性的任务,用于计算体素级语义面具。为了提高编码器 - 解码器神经网络在大型临床队列中执行这项任务的能力,对比学习提供了稳定模型初始化和增强编码器而无需标签的机会。然而,多个目标对象(具有不同的语义含义)可能存在于单个图像中,这使得适应传统的对比学习方法从普遍的“图像级分类”到“像素级分段”中的问题。在本文中,我们提出了一种简单的语义感知对比学习方法,利用注意掩模来推进多对象语义分割。简而言之,我们将不同的语义对象嵌入不同的群集而不是传统的图像级嵌入。我们在与内部数据和Miccai挑战2015 BTCV数据集中的多器官医学图像分段任务中评估我们提出的方法。与目前的最先进的培训策略相比,我们拟议的管道分别产生了两种医学图像分割队列的骰子评分的大幅提高5.53%和6.09%(P值<0.01)。通过Pascal VOC 2012 DataSet进一步评估了所提出的方法的性能,并在MiOU(P值<0.01)上实现了2.75%的大幅提高。
translated by 谷歌翻译
在2D多板磁共振(MR)采集中,平面信号通常比面内信号较低。尽管当代超分辨率(SR)方法旨在恢复基本的高分辨率量,但估计的高频信息是通过端到端数据驱动的培训隐含的,而不是明确说明和寻求。为了解决这个问题,我们根据完美的重建过滤库重新构架SR问题声明,使我们能够识别并直接估计缺失的信息。在这项工作中,我们提出了一种两阶段的方法,以近似于与特定扫描的各向异性采集相对应的完美重建过滤库。在第1阶段,我们使用梯度下降估算缺失的过滤器,在第2阶段,我们使用深网来学习从粗系数到细节系数的映射。此外,提出的公式不依赖外部训练数据,从而规避了对域移位校正的需求。在我们的方法下,特别是在“切片差距”方案中提高了SR性能,这可能是由于框架施加的解决方案空间的限制。
translated by 谷歌翻译
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。
translated by 谷歌翻译
尽管近期因因果推断领域的进展,迄今为止没有关于从观察数据的收集治疗效应估算的方法。对临床实践的结果是,当缺乏随机试验的结果时,没有指导在真实情景中似乎有效的指导。本文提出了一种务实的方法,以获得从观察性研究的治疗效果的初步但稳健地估算,为前线临床医生提供对其治疗策略的信心程度。我们的研究设计适用于一个公开问题,估算Covid-19密集护理患者的拳击机动的治疗效果。
translated by 谷歌翻译
强盗算法越来越多地用于现实世界的连续决策问题。与之相关的是能够使用所产生的数据集来支持科学问题的增加,如:一种类型的广告导致更多购买?哪些背景是移动健康干预有效?然而,当与带有强盗算法收集的数据一起使用时,经典统计方法无法提供有效的置信区间。最近已经开发了用于简单模型的替代方法(例如,手段的比较)。然而,使用使用(上下文)强盗算法收集的数据的更复杂模型,缺乏对统计推断进行统计推理的一般方法;例如,当前方法不能用于逻辑回归模型中的参数的有效推断,以获得二进制奖励。在这项工作中,我们开发理论证明使用M估算器的使用 - 这包括基于经验风险最小化的估计,以及最大可能性 - 与自适应算法收集的数据,包括(上下文)强盗算法。具体地,我们表明,用特定自适应重量修改的M估算器可用于构建用于各种推理目标的渐近有效的置信区。
translated by 谷歌翻译
Making histopathology image classifiers robust to a wide range of real-world variability is a challenging task. Here, we describe a candidate deep learning solution for the Mitosis Domain Generalization Challenge 2022 (MIDOG) to address the problem of generalization for mitosis detection in images of hematoxylin-eosin-stained histology slides under high variability (scanner, tissue type and species variability). Our approach consists in training a rotation-invariant deep learning model using aggressive data augmentation with a training set enriched with hard negative examples and automatically selected negative examples from the unlabeled part of the challenge dataset. To optimize the performance of our models, we investigated a hard negative mining regime search procedure that lead us to train our best model using a subset of image patches representing 19.6% of our training partition of the challenge dataset. Our candidate model ensemble achieved a F1-score of .697 on the final test set after automated evaluation on the challenge platform, achieving the third best overall score in the MIDOG 2022 Challenge.
translated by 谷歌翻译
Supervised Question Answering systems (QA systems) rely on domain-specific human-labeled data for training. Unsupervised QA systems generate their own question-answer training pairs, typically using secondary knowledge sources to achieve this outcome. Our approach (called PIE-QG) uses Open Information Extraction (OpenIE) to generate synthetic training questions from paraphrased passages and uses the question-answer pairs as training data for a language model for a state-of-the-art QA system based on BERT. Triples in the form of <subject, predicate, object> are extracted from each passage, and questions are formed with subjects (or objects) and predicates while objects (or subjects) are considered as answers. Experimenting on five extractive QA datasets demonstrates that our technique achieves on-par performance with existing state-of-the-art QA systems with the benefit of being trained on an order of magnitude fewer documents and without any recourse to external reference data sources.
translated by 谷歌翻译
While the capabilities of autonomous systems have been steadily improving in recent years, these systems still struggle to rapidly explore previously unknown environments without the aid of GPS-assisted navigation. The DARPA Subterranean (SubT) Challenge aimed to fast track the development of autonomous exploration systems by evaluating their performance in real-world underground search-and-rescue scenarios. Subterranean environments present a plethora of challenges for robotic systems, such as limited communications, complex topology, visually-degraded sensing, and harsh terrain. The presented solution enables long-term autonomy with minimal human supervision by combining a powerful and independent single-agent autonomy stack, with higher level mission management operating over a flexible mesh network. The autonomy suite deployed on quadruped and wheeled robots was fully independent, freeing the human supervision to loosely supervise the mission and make high-impact strategic decisions. We also discuss lessons learned from fielding our system at the SubT Final Event, relating to vehicle versatility, system adaptability, and re-configurable communications.
translated by 谷歌翻译
While the brain connectivity network can inform the understanding and diagnosis of developmental dyslexia, its cause-effect relationships have not yet enough been examined. Employing electroencephalography signals and band-limited white noise stimulus at 4.8 Hz (prosodic-syllabic frequency), we measure the phase Granger causalities among channels to identify differences between dyslexic learners and controls, thereby proposing a method to calculate directional connectivity. As causal relationships run in both directions, we explore three scenarios, namely channels' activity as sources, as sinks, and in total. Our proposed method can be used for both classification and exploratory analysis. In all scenarios, we find confirmation of the established right-lateralized Theta sampling network anomaly, in line with the temporal sampling framework's assumption of oscillatory differences in the Theta and Gamma bands. Further, we show that this anomaly primarily occurs in the causal relationships of channels acting as sinks, where it is significantly more pronounced than when only total activity is observed. In the sink scenario, our classifier obtains 0.84 and 0.88 accuracy and 0.87 and 0.93 AUC for the Theta and Gamma bands, respectively.
translated by 谷歌翻译