密度峰值聚类(density peaks clustering,DPC)是一种基于密度的聚类算法,该算法可以直观地确定类簇数量,识别任意形状的类簇,并且自动检测、排除异常点.然而,DPC仍存在些许不足:一方面,DPC算法仅考虑全局分布,在类簇密度差距较大的数据...密度峰值聚类(density peaks clustering,DPC)是一种基于密度的聚类算法,该算法可以直观地确定类簇数量,识别任意形状的类簇,并且自动检测、排除异常点.然而,DPC仍存在些许不足:一方面,DPC算法仅考虑全局分布,在类簇密度差距较大的数据集聚类效果较差;另一方面,DPC中点的分配策略容易导致“多米诺效应”.为此,基于代表点(representative points)与K近邻(K-nearest neighbors,KNN)提出了RKNN-DPC算法.首先,构造了K近邻密度,再引入代表点刻画样本的全局分布,提出了新的局部密度;然后,利用样本的K近邻信息,提出一种加权的K近邻分配策略以缓解“多米诺效应”;最后,在人工数据集和真实数据集上与5种聚类算法进行了对比实验,实验结果表明,所提出的RKNN-DPC可以更准确地识别类簇中心并且获得更好的聚类结果.展开更多
研究了打浆转数对棉短绒打浆度、湿重、成纸强度的影响以及不同预处理条件对棉短绒打浆性能的影响,还对棉短绒对纱管纸生产的影响进行了研究。研究结果表明:棉短绒浆料打浆转数应控制在3000~6000r、打浆度应达到70°S R左右才能减...研究了打浆转数对棉短绒打浆度、湿重、成纸强度的影响以及不同预处理条件对棉短绒打浆性能的影响,还对棉短绒对纱管纸生产的影响进行了研究。研究结果表明:棉短绒浆料打浆转数应控制在3000~6000r、打浆度应达到70°S R左右才能减少纤维切断并满足纱管纸生产使用要求。在氢氧化钠用量为30kg/t、渗透剂用量为0.2kg/t的条件下将浓度为10%棉短绒浆于60℃下处理60m i n,可以明显改善棉短绒打浆性能。配用棉短绒浆料可以提高混合浆料的长纤维含量,从而改善浆料的保留和滤水效果及成纸强度。展开更多
Excess ammonia(NH_(3))in the circulation of dairy animals can reduce animal health and the quality of products for human consumption.To develop effective prevention and treatment methods,it is essential to examine the...Excess ammonia(NH_(3))in the circulation of dairy animals can reduce animal health and the quality of products for human consumption.To develop effective prevention and treatment methods,it is essential to examine the molecular mechanisms through which excess NH_(3) may affect the mammary gland.The present study used bovine mammary epithelial cells(BMECs)to evaluate the effects of exogenous NH_(4)Cl on the abundance of circular RNAs(circRNAs)using high-throughput sequencing.Among the identified circRNAs,circ02771 was the most significantly upregulated by exogenous NH_(4)Cl(P<0.05),with a fold change of 4.12.The results of the apoptosis and proliferation assays,transmission electron microscopy,H&E staining,and immunohistochemistry revealed that circ02771 increased apoptosis and inflammation.A double luciferase reporter assay revealed that circ02771 targeted miR-194b,and the overexpression of circ02771(pcDNA-circ02771)reduced(P<0.05)the expression of miR-194b and led to apoptosis and inflammation.Circ02771 also enhanced the expression of transforming growth factor beta-induced factor homeobox 1(TGIF1),which is a target gene of miR-194b.Overall,this study suggests that the circ02771/miR-194b/TGIF1 axis plays a role in mediating the effects of NH_(4)Cl on BMECs.Therefore,this axis provides a novel target to help control hazards within the mammary gland from high circulating NH_(4)Cl levels.展开更多
文摘密度峰值聚类(density peaks clustering,DPC)是一种基于密度的聚类算法,该算法可以直观地确定类簇数量,识别任意形状的类簇,并且自动检测、排除异常点.然而,DPC仍存在些许不足:一方面,DPC算法仅考虑全局分布,在类簇密度差距较大的数据集聚类效果较差;另一方面,DPC中点的分配策略容易导致“多米诺效应”.为此,基于代表点(representative points)与K近邻(K-nearest neighbors,KNN)提出了RKNN-DPC算法.首先,构造了K近邻密度,再引入代表点刻画样本的全局分布,提出了新的局部密度;然后,利用样本的K近邻信息,提出一种加权的K近邻分配策略以缓解“多米诺效应”;最后,在人工数据集和真实数据集上与5种聚类算法进行了对比实验,实验结果表明,所提出的RKNN-DPC可以更准确地识别类簇中心并且获得更好的聚类结果.
文摘研究了打浆转数对棉短绒打浆度、湿重、成纸强度的影响以及不同预处理条件对棉短绒打浆性能的影响,还对棉短绒对纱管纸生产的影响进行了研究。研究结果表明:棉短绒浆料打浆转数应控制在3000~6000r、打浆度应达到70°S R左右才能减少纤维切断并满足纱管纸生产使用要求。在氢氧化钠用量为30kg/t、渗透剂用量为0.2kg/t的条件下将浓度为10%棉短绒浆于60℃下处理60m i n,可以明显改善棉短绒打浆性能。配用棉短绒浆料可以提高混合浆料的长纤维含量,从而改善浆料的保留和滤水效果及成纸强度。
基金supported by the Independent Innovation in Jiangsu Province of China(CX(21)3119)the National Natural Science Foundation of China(31802035,31702095 and 31872324)+1 种基金the Jiangsu Natural Science Fund(BK20181221)Yangzhou Liangde Antibody Bio Tech.,China。
文摘Excess ammonia(NH_(3))in the circulation of dairy animals can reduce animal health and the quality of products for human consumption.To develop effective prevention and treatment methods,it is essential to examine the molecular mechanisms through which excess NH_(3) may affect the mammary gland.The present study used bovine mammary epithelial cells(BMECs)to evaluate the effects of exogenous NH_(4)Cl on the abundance of circular RNAs(circRNAs)using high-throughput sequencing.Among the identified circRNAs,circ02771 was the most significantly upregulated by exogenous NH_(4)Cl(P<0.05),with a fold change of 4.12.The results of the apoptosis and proliferation assays,transmission electron microscopy,H&E staining,and immunohistochemistry revealed that circ02771 increased apoptosis and inflammation.A double luciferase reporter assay revealed that circ02771 targeted miR-194b,and the overexpression of circ02771(pcDNA-circ02771)reduced(P<0.05)the expression of miR-194b and led to apoptosis and inflammation.Circ02771 also enhanced the expression of transforming growth factor beta-induced factor homeobox 1(TGIF1),which is a target gene of miR-194b.Overall,this study suggests that the circ02771/miR-194b/TGIF1 axis plays a role in mediating the effects of NH_(4)Cl on BMECs.Therefore,this axis provides a novel target to help control hazards within the mammary gland from high circulating NH_(4)Cl levels.