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
目的探讨叙事护理在肿瘤患者经外周静脉置入中心静脉导管(peripherally inserted central catheter,PICC)留置期间延续性护理中的应用效果。方法选取2023年12月—2024年5月在厦门大学附属第一医院行PICC维护的100例肿瘤患者,采用随机数...目的探讨叙事护理在肿瘤患者经外周静脉置入中心静脉导管(peripherally inserted central catheter,PICC)留置期间延续性护理中的应用效果。方法选取2023年12月—2024年5月在厦门大学附属第一医院行PICC维护的100例肿瘤患者,采用随机数字表法分为试验组和对照组各50例,试验组给予叙事护理模式进行延续护理,对照组给予常规延续护理,比较2组干预前后自我倡权、生活质量、并发症及依从性。结果干预后试验组自我倡权总分为(87.67±3.73)分,高于对照组的(71.90±7.15)分,差异有统计学意义(P<0.001)。干预后试验组总体健康状况评分为(77.55±8.87)分,高于对照组的(70.31±12.27)分,差异有统计学意义(P<0.05);试验组躯体功能、角色功能、情绪功能、社会功能评分均高于对照组,疲劳、恶心呕吐、食欲减退、腹泻评分均低于对照组,差异有统计学意义(P<0.05)。干预后试验组并发症发生率为10.2%,低于对照组的37.5%,差异有统计学意义(P<0.05)。干预后试验组导管维护缺失次数、缺失患者例数占比分别为1.9%、10.2%,低于对照组的8.0%、27.1%,差异有统计学意义(P<0.05)。结论叙事护理可提高肿瘤患者自我倡权水平,改善生活质量并提高患者导管维护依从性,降低并发症发生率。展开更多
近年来,激光粉末床熔融(laser powder bed fusion,LPBF)作为一种先进的增材制造技术,已吸引了广泛的关注和研究。利用其高自由度的成形方式,可以设计制造出合适的冷却流道来对热作模具进行控温,从而提高模具的冷却效率及使用寿命。因此,...近年来,激光粉末床熔融(laser powder bed fusion,LPBF)作为一种先进的增材制造技术,已吸引了广泛的关注和研究。利用其高自由度的成形方式,可以设计制造出合适的冷却流道来对热作模具进行控温,从而提高模具的冷却效率及使用寿命。因此,LPBF技术在热作模具的成形制造中得到了广泛应用。H13钢具有高强度、高硬度、良好的耐回火性等优点,是热作模具最常用的工具钢之一。关于LPBF技术在H13钢中的应用一直是该领域的研究焦点,也已取得显著进展。基于此,首先阐述了LPBF制备H13钢的成形性能,分析了打印工艺参数对成形缺陷的影响,介绍了控制打印开裂的方法;其次,对沉积态与热处理态的LPBF成形H13钢的微观组织和力学性能进行介绍,详细论述了打印成形及后续热处理过程中的组织演化,在此基础上分析了微观组织对强度、硬度、塑性等方面的影响;同时也对LPBF成形H13钢在热作模具中的服役性能进行了总结,沉积态的LPBF成形H13钢具有良好的抗回火软化及抗热疲劳性能。最后,对具有随形冷却流道的LPBF成形H13钢热作模具在实际中的应用情况进行了总结分析,指出随形冷却流道在提高冷却效率、延长模具使用寿命等方面的显著优势。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。
文摘目的探讨叙事护理在肿瘤患者经外周静脉置入中心静脉导管(peripherally inserted central catheter,PICC)留置期间延续性护理中的应用效果。方法选取2023年12月—2024年5月在厦门大学附属第一医院行PICC维护的100例肿瘤患者,采用随机数字表法分为试验组和对照组各50例,试验组给予叙事护理模式进行延续护理,对照组给予常规延续护理,比较2组干预前后自我倡权、生活质量、并发症及依从性。结果干预后试验组自我倡权总分为(87.67±3.73)分,高于对照组的(71.90±7.15)分,差异有统计学意义(P<0.001)。干预后试验组总体健康状况评分为(77.55±8.87)分,高于对照组的(70.31±12.27)分,差异有统计学意义(P<0.05);试验组躯体功能、角色功能、情绪功能、社会功能评分均高于对照组,疲劳、恶心呕吐、食欲减退、腹泻评分均低于对照组,差异有统计学意义(P<0.05)。干预后试验组并发症发生率为10.2%,低于对照组的37.5%,差异有统计学意义(P<0.05)。干预后试验组导管维护缺失次数、缺失患者例数占比分别为1.9%、10.2%,低于对照组的8.0%、27.1%,差异有统计学意义(P<0.05)。结论叙事护理可提高肿瘤患者自我倡权水平,改善生活质量并提高患者导管维护依从性,降低并发症发生率。
文摘近年来,激光粉末床熔融(laser powder bed fusion,LPBF)作为一种先进的增材制造技术,已吸引了广泛的关注和研究。利用其高自由度的成形方式,可以设计制造出合适的冷却流道来对热作模具进行控温,从而提高模具的冷却效率及使用寿命。因此,LPBF技术在热作模具的成形制造中得到了广泛应用。H13钢具有高强度、高硬度、良好的耐回火性等优点,是热作模具最常用的工具钢之一。关于LPBF技术在H13钢中的应用一直是该领域的研究焦点,也已取得显著进展。基于此,首先阐述了LPBF制备H13钢的成形性能,分析了打印工艺参数对成形缺陷的影响,介绍了控制打印开裂的方法;其次,对沉积态与热处理态的LPBF成形H13钢的微观组织和力学性能进行介绍,详细论述了打印成形及后续热处理过程中的组织演化,在此基础上分析了微观组织对强度、硬度、塑性等方面的影响;同时也对LPBF成形H13钢在热作模具中的服役性能进行了总结,沉积态的LPBF成形H13钢具有良好的抗回火软化及抗热疲劳性能。最后,对具有随形冷却流道的LPBF成形H13钢热作模具在实际中的应用情况进行了总结分析,指出随形冷却流道在提高冷却效率、延长模具使用寿命等方面的显著优势。
