外装门锁钥匙插拔卡滞问题检测与分析

针对新安装门锁钥匙插拔卡滞而打开困难的问题,在SG17-03型钥匙拔出力测试仪上进行了钥匙拔出力测试.介绍了门锁检测过程,分析了门锁钥匙插拔卡滞原因,通过解体检验及拔出力测试提出了解决办法.     

Neutrophils Mediate Pulmonary Artery Thrombosis In Situ

Pulmonary embolism is a life-threatening condition, which can result in respiratory insufficiency and death. Blood clots occluding branches of the pulmonary artery (PA) are traditionally considered to originate from thrombi in deep veins (usually in legs). However, growing evidence suggests that occlusion of the vessels in the lungs can develop without preceding deep vein thrombosis (DVT). In this work, we used an inferior vena cava (IVC) complete ligation model of DVT in Wistar rats to explore the possibility and mechanisms of PA thrombosis under the conditions where all routes of thrombotic mass migration from peripheral veins are blocked. We demonstrate that rats both with normal and reduced neutrophil counts developed thrombi in the IVC, although, neutropenia caused a substantial decrease in thrombus size and a shift from fresh fibrin toward mature fibrin and connective tissue inside the thrombus. Massive fibrin deposition was found in the PA branches in the majority of DVT rats with normal neutrophil counts, but in none of the neutropenic animals. Neutrophil ablation also abolished macroscopic signs of lung damage. Altogether, the results demonstrate that thrombi in the lung vasculature can form in situ by mechanisms that require local neutrophil recruitment taking place in the DVT setting.     

深部开采岩体变形分析的双曲函数法

在软岩地层深部厚矿体开采条件下,给出了用于预测分析地下开采岩体移动变形的双曲正切函数模型,采用该模型对国内某地下矿山深部开采岩体移动变形进行了具体的计算分析,并与概率积分法理论分析结果和实测数据进行了对比,结果令人满意.分析结果表明,本文所提出的理论方法适用于预测分析深部矿体开采引起的岩体移动变形问题.     

CSatDTA: Prediction of Drug–Target Binding Affinity Using Convolution Model with Self-Attention

Drug discovery, which aids to identify potential novel treatments, entails a broad range of fields of science, including chemistry, pharmacology, and biology. In the early stages of drug development, predicting drug–target affinity is crucial. The proposed model, the prediction of drug–target affinity using a convolution model with self-attention (CSatDTA), applies convolution-based self-attention mechanisms to the molecular drug and target sequences to predict drug–target affinity (DTA) effectively, unlike previous convolution methods, which exhibit significant limitations related to this aspect. The convolutional neural network (CNN) only works on a particular region of information, excluding comprehensive details. Self-attention, on the other hand, is a relatively recent technique for capturing long-range interactions that has been used primarily in sequence modeling tasks. The results of comparative experiments show that CSatDTA surpasses previous sequence-based or other approaches and has outstanding retention abilities.     

基于深度学习的眼底血管图像分割研究进展

眼底血管图像分割对青光眼、糖尿病视网膜病变等多种眼部疾病有较好的辅助诊断作用, 目前深度学习因其强大的抽象特征发现能力, 有望满足人们从眼底血管图像中提取特征信息进行图像自动分割的需求, 成为眼底血管图像分割领域的研究热点. 为更好把握该领域的研究进展, 本文对相关数据集和评价指标整理归纳, 对深度学习在眼底血管图像分割中的应用进行详细阐述, 重点梳理各类分割方法的基本思想、网络结构及改进之处, 分析现有眼底血管图像分割方法存在的局限性及面临的挑战, 并对该领域未来的研究方向做出展望.     

跨模态融合的双注意力脑肿瘤分割算法

针对脑肿瘤多模态信息融合不充分以及肿瘤区域细节信息丢失等问题,提出了一种跨模态融合的双注意力脑肿瘤图像分割网络(CFDA-Net).在编码器-解码器的基础结构上,首先在编码器分支采用密集块与大内核注意力并行的新卷积块,可以使全局和局部信息有效融合且可以防止反向传播时梯度消失的问题;其次在编码器的第2、3和4层的左侧加入多模态深度融合模块,有效地利用不同模态间的互补信息;然后在解码器分支使用Shuffle Attention注意力将特征图分组处理后再聚合,其中分组的子特征一分为二地获取空间与通道的重要注意特征.最后使用二进制交叉熵(binary cross entropy, BCE)、Dice Loss与L2 Loss组成新的混合损失函数,缓解了脑肿瘤数据的类别不平衡问题,进一步提升分割性能.在BraTS2019脑肿瘤数据集上的实验结果表明,该模型在整体肿瘤区域、肿瘤核心区域和肿瘤增强区域的平均Dice系数值分别为0.887、0.892和0.815.与其他先进的分割方法 ADHDC-Net、SDS-MSA-Net等相比,该模型在肿瘤核心区域和增强区域具有更好的分割效果.     

基于YOLO的钢缆表面损坏检测

为了解决检测钢缆表面损坏时检测设备资源有限、时间过长等问题,将深度学习的先进技术以及卷积神经网络(CNN)应用于钢缆表面损坏检测.提出了一种基于YOLO的缺陷检测网络模型,将GhostNet融入主干网络,并基于ShuffleNet及注意力机制提出了新的特征提取模块(ShuffleC3),再对Head部分进行剪枝改进.实验结果表明,改进后网络相比基线YOLOv5s的平均精度提高1.1%,参数量和计算量分别降低了43.4%和31%,模型大小减少了42.3%.可以在降低网络计算成本的同时,保持较高的识别精确度,更好地满足了对钢缆材料表面损坏检测的要求.     

改进AOD-Net的道路交通图像去雾算法

针对现有图像去雾算法在处理道路交通图像时无法同时兼顾去雾效果和实时性的问题,本文以快速一体化网络去雾算法(AOD-Net)为基础进行改进.首先,在AOD-Net中添加SE通道注意力,以自适应的方式分配通道权重,关注重要特征;其次,引入金字塔池化模块,扩大网络的感受野,并融合不同尺度特征,更好地捕捉图像信息;最后,使用复合损失函数同时关注图像像素信息和结构纹理信息.实验结果表明,改进后的AOD-Net算法对道路交通图像去雾后的峰值信噪比提升了2.52 dB,结构相似度达到了91.2%,算法复杂度和去雾耗时略微增加,但仍满足实时要求.     

跨层协同注意和通道分组注意的细粒度图像分类

细粒度图像分类的主要挑战在于类间的高度相似性和类内的差异性. 现有的研究多数基于深层的特征而忽略了浅层细节信息, 然而深层的语义特征由于多次卷积和池化操作往往会丢失大量的细节信息. 为了更好地整合浅层和深层的信息, 提出了基于跨层协同注意和通道分组注意的细粒度图像分类方法. 首先, 通过ResNet50加载预训练模型作为骨干网络提取特征, 由最后3个阶段提取的特征以3个分支的形式输出, 每一个分支的特征通过跨层的方式与其余两个分支的特征计算协同注意并交互融合, 其中最后一个阶段的特征经过通道分组注意模块以增强语义特征的学习能力. 模型训练可以高效地以端到端的方式在没有边界框和注释的情况下进行训练, 实验结果表明, 该算法在3个常用细粒度图像数据集CUB-200-2011、Stanford Cars和FGVC-Aircraft上的准确率分别达到了89.5%、94.8%和94.7%.     

Protein–Protein Interaction Prediction for Targeted Protein Degradation

Protein–protein interactions (PPIs) play a fundamental role in various biological functions; thus, detecting PPI sites is essential for understanding diseases and developing new drugs. PPI prediction is of particular relevance for the development of drugs employing targeted protein degradation, as their efficacy relies on the formation of a stable ternary complex involving two proteins. However, experimental methods to detect PPI sites are both costly and time-intensive. In recent years, machine learning-based methods have been developed as screening tools. While they are computationally more efficient than traditional docking methods and thus allow rapid execution, these tools have so far primarily been based on sequence information, and they are therefore limited in their ability to address spatial requirements. In addition, they have to date not been applied to targeted protein degradation. Here, we present a new deep learning architecture based on the concept of graph representation learning that can predict interaction sites and interactions of proteins based on their surface representations. We demonstrate that our model reaches state-of-the-art performance using AUROC scores on the established MaSIF dataset. We furthermore introduce a new dataset with more diverse protein interactions and show that our model generalizes well to this new data. These generalization capabilities allow our model to predict the PPIs relevant for targeted protein degradation, which we show by demonstrating the high accuracy of our model for PPI prediction on the available ternary complex data. Our results suggest that PPI prediction models can be a valuable tool for screening protein pairs while developing new drugs for targeted protein degradation.