A pyramid sheet has been used in experiments and three-dimensional finite element simulation to study the edge cracks and effects of width on AZ31 sheet under rolling. Results show that the edge cracks of Mg sheet com...A pyramid sheet has been used in experiments and three-dimensional finite element simulation to study the edge cracks and effects of width on AZ31 sheet under rolling. Results show that the edge cracks of Mg sheet comply with the Normalized Crockroft ＆ Latham theory. It can be predicted by D=-0.124＋0.09X - 0.008X2, if D ;〉 0, the edge cracks occur. The sheet shearing deformation at the edge brings about cracks. The strain rate changes periodically with different X. With initial width increases, the recrystallized grain size decreases. The finite element model has been validated by the experiment results.展开更多
Breast cancer(BC)is one of the most common cancers and the leading causes of death among women worldwide,and its morbidity rate is growing.Discovery of novel biomarkers is necessary for early BC detection,treatment,an...Breast cancer(BC)is one of the most common cancers and the leading causes of death among women worldwide,and its morbidity rate is growing.Discovery of novel biomarkers is necessary for early BC detection,treatment,and prognostication.Circular RNAs(circ RNAs),a novel type of endogenous non-coding RNAs with covalently closed continuous loops,have been found to have a crucial role in tumorigenesis.Studies have demonstrated that circ RNAs are aberrantly expressed in the tumor tissues and plasma of patients with BC,and they modulate gene expression affecting the proliferation,metastasis,and chemoresistance of BC by specifically binding and regulating the expression of micro RNAs(mi RNAs).Therefore,circ RNAs can be used as novel potential diagnostic and prognostic markers,and therapeutic targets for BC.This article summarizes the properties,functions,and regulatory mechanisms of circ RNAs,particularly current research on their association with BC proliferation,metastasis,and chemoresistance.展开更多
为解决YOLOv8n算法在机场异物检测中存在计算复杂度高、计算资源消耗大的问题,通过在YOLOv8n算法中引入轻量化模块的方法研究了机场异物检测的问题,提出了Fast-BiYOLOv8n算法。首先,设计了C2f_FasterEMA模块并引入YOLOv8n算法的骨干网络...为解决YOLOv8n算法在机场异物检测中存在计算复杂度高、计算资源消耗大的问题,通过在YOLOv8n算法中引入轻量化模块的方法研究了机场异物检测的问题,提出了Fast-BiYOLOv8n算法。首先,设计了C2f_FasterEMA模块并引入YOLOv8n算法的骨干网络中,该模块融合了FasterBlock模块和高效多尺度注意力(efficient multi-scale attention,EMA)注意力机制,增强了图像的特征提取能力,同时降低了算法计算量;其次,在路径聚合网络(path aggregation network,PANet,)网络架构中融合了骨干网络中的P2特征层并设计了双向特征金字塔网络(bidirectional feature pyramid network,BiFPN)网络架构,增加了跨尺度连接促进了不同特征图之间的信息融合,同时加入C2f_Faster模块提高了特征融合的效率并进一步降低了算法的计算量;最后,通过改进损失函数为Inner-CIoU(intersection over union,complete intersection over union loss)加快了算法的收敛速度,提高了检测准确率。结果表明,Fast-BiYOLOv8n算法的检测准确率达到99.0%,召回率为98.8%,平均精度均值(mean average precision,mAP)提升了3.5个百分点,达到99.3%,参数量比原模型降低了27%,模型的权重大小降低了21%,实现了在降低算法参数量的同时,提升检测准确率的目的。展开更多
基金supported by 973 National Grand Theoretical Research Program(No.2007CB613700)National Sci & Technol Support Program (No.2007BAG06B04)+1 种基金Chongqing Sci & Technol Program (CSTC,2009AB4008)National Natural Science Foundation of China (No.50725413)
文摘A pyramid sheet has been used in experiments and three-dimensional finite element simulation to study the edge cracks and effects of width on AZ31 sheet under rolling. Results show that the edge cracks of Mg sheet comply with the Normalized Crockroft ＆ Latham theory. It can be predicted by D=-0.124＋0.09X - 0.008X2, if D ;〉 0, the edge cracks occur. The sheet shearing deformation at the edge brings about cracks. The strain rate changes periodically with different X. With initial width increases, the recrystallized grain size decreases. The finite element model has been validated by the experiment results.
基金supported by the Shanghai Municipal Science and Technology Commission,China(Grant No.17411967200)。
文摘Breast cancer(BC)is one of the most common cancers and the leading causes of death among women worldwide,and its morbidity rate is growing.Discovery of novel biomarkers is necessary for early BC detection,treatment,and prognostication.Circular RNAs(circ RNAs),a novel type of endogenous non-coding RNAs with covalently closed continuous loops,have been found to have a crucial role in tumorigenesis.Studies have demonstrated that circ RNAs are aberrantly expressed in the tumor tissues and plasma of patients with BC,and they modulate gene expression affecting the proliferation,metastasis,and chemoresistance of BC by specifically binding and regulating the expression of micro RNAs(mi RNAs).Therefore,circ RNAs can be used as novel potential diagnostic and prognostic markers,and therapeutic targets for BC.This article summarizes the properties,functions,and regulatory mechanisms of circ RNAs,particularly current research on their association with BC proliferation,metastasis,and chemoresistance.
文摘为解决YOLOv8n算法在机场异物检测中存在计算复杂度高、计算资源消耗大的问题,通过在YOLOv8n算法中引入轻量化模块的方法研究了机场异物检测的问题,提出了Fast-BiYOLOv8n算法。首先,设计了C2f_FasterEMA模块并引入YOLOv8n算法的骨干网络中,该模块融合了FasterBlock模块和高效多尺度注意力(efficient multi-scale attention,EMA)注意力机制,增强了图像的特征提取能力,同时降低了算法计算量;其次,在路径聚合网络(path aggregation network,PANet,)网络架构中融合了骨干网络中的P2特征层并设计了双向特征金字塔网络(bidirectional feature pyramid network,BiFPN)网络架构,增加了跨尺度连接促进了不同特征图之间的信息融合,同时加入C2f_Faster模块提高了特征融合的效率并进一步降低了算法的计算量;最后,通过改进损失函数为Inner-CIoU(intersection over union,complete intersection over union loss)加快了算法的收敛速度,提高了检测准确率。结果表明,Fast-BiYOLOv8n算法的检测准确率达到99.0%,召回率为98.8%,平均精度均值(mean average precision,mAP)提升了3.5个百分点,达到99.3%,参数量比原模型降低了27%,模型的权重大小降低了21%,实现了在降低算法参数量的同时,提升检测准确率的目的。
