利用目标区域捕获测序技术对BF2(Major histocompatibility complex class I antigen BF2)基因进行序列测定,找出不同鸡种BF2基因序列上的差异。以NCBI网站上Gallus_gallus-5.0的BF2基因序列为参照标准。利用MEGA6.06软件对25个鸡种的...利用目标区域捕获测序技术对BF2(Major histocompatibility complex class I antigen BF2)基因进行序列测定,找出不同鸡种BF2基因序列上的差异。以NCBI网站上Gallus_gallus-5.0的BF2基因序列为参照标准。利用MEGA6.06软件对25个鸡种的基因序列进行比对分析,统计SNPs位点和Indel位点,并构建系统进化树进行分析。结果表明:在BF2第2、3外显子上分别存在22和31个有义突变,占BF2基因全部有义突变的78%,表明BF2基因的第2、3外显子起重要作用且拥有丰富的多态性。第5、6、7外显子属于保守区域。25个鸡种大致可被分为3大类:鹿苑鸡、如皋黄鸡、溧阳鸡和太湖鸡等聚为一类;罗斯鸡和隐性白羽肉鸡等聚为一类;雪山鸡和广西黄鸡等聚为一类。表明中国地方鸡品种间的同源性较小,BF2基因在不同鸡种上具有丰富的遗传多样性,在第2外显子上C/T突变和第3外显子上A/C突变可作为BF2基因有关抗病的候选SNPs位点。展开更多
针对背景复杂的变电站电力设备过热故障红外图像难以检测的问题,提出了改进你只看一次11纳米版(you only look once version 11 nano, YOLOv11n)算法。首先,采用轻量级跨尺度特征融合模块(cross-scale feature fusion module, CCFM)改...针对背景复杂的变电站电力设备过热故障红外图像难以检测的问题,提出了改进你只看一次11纳米版(you only look once version 11 nano, YOLOv11n)算法。首先,采用轻量级跨尺度特征融合模块(cross-scale feature fusion module, CCFM)改进原有颈部网络,以实现对特征通道信息的高效整合并降低参数量;其次,引入具有可切换空洞卷积的2次跨阶段3卷积可变核(cross stage partial with three-convolution blocks of variable kernel size two-switchable atrous convolution, C3k2-SAConv)模块替换整个网络的C3k2模块,提升了算法的特征提取能力;最后,使用具有双层路由注意力视觉转换器的跨阶段双卷积(cross stage partial with two convolutions and vision transformer of bi-level routing attention, C2BF)模块替换跨阶段双卷积逐点空间注意力(cross stage partial with two convolutions and pointwise spatial attention, C2PSA)模块,提升了算法在复杂环境下对红外图像的检测准确度。结果表明,相较于原始YOLOv11n算法,改进YOLOv11n算法的参数量减少了22.1%;精确率、召回率、平均精确率均值分别达到91.1%、85.5%、90.9%,各自提升了3.0、2.6、2.8个百分点;检测速度达到128.2帧/s。改进YOLOv11n算法能实现对电力设备过热故障红外图像的有效检测,可满足算法轻量化与实时性检测的要求。展开更多
Six novel pyrromethene- BF2 complexes,of which five compounds have not been reported,were synthesized and characterized.Their relationships between structure and photophysical behavior were studied with the aid of flu...Six novel pyrromethene- BF2 complexes,of which five compounds have not been reported,were synthesized and characterized.Their relationships between structure and photophysical behavior were studied with the aid of fluorescence and triplet state absorption spectra.The results indicate that,compared to 8- alkylpyrromethene- BF2 complexes,the compounds containing 8- aryl exhibit high fluorescence quantum yield and rather low triplet state absorption.展开更多
文摘利用目标区域捕获测序技术对BF2(Major histocompatibility complex class I antigen BF2)基因进行序列测定,找出不同鸡种BF2基因序列上的差异。以NCBI网站上Gallus_gallus-5.0的BF2基因序列为参照标准。利用MEGA6.06软件对25个鸡种的基因序列进行比对分析,统计SNPs位点和Indel位点,并构建系统进化树进行分析。结果表明:在BF2第2、3外显子上分别存在22和31个有义突变,占BF2基因全部有义突变的78%,表明BF2基因的第2、3外显子起重要作用且拥有丰富的多态性。第5、6、7外显子属于保守区域。25个鸡种大致可被分为3大类:鹿苑鸡、如皋黄鸡、溧阳鸡和太湖鸡等聚为一类;罗斯鸡和隐性白羽肉鸡等聚为一类;雪山鸡和广西黄鸡等聚为一类。表明中国地方鸡品种间的同源性较小,BF2基因在不同鸡种上具有丰富的遗传多样性,在第2外显子上C/T突变和第3外显子上A/C突变可作为BF2基因有关抗病的候选SNPs位点。
文摘针对背景复杂的变电站电力设备过热故障红外图像难以检测的问题,提出了改进你只看一次11纳米版(you only look once version 11 nano, YOLOv11n)算法。首先,采用轻量级跨尺度特征融合模块(cross-scale feature fusion module, CCFM)改进原有颈部网络,以实现对特征通道信息的高效整合并降低参数量;其次,引入具有可切换空洞卷积的2次跨阶段3卷积可变核(cross stage partial with three-convolution blocks of variable kernel size two-switchable atrous convolution, C3k2-SAConv)模块替换整个网络的C3k2模块,提升了算法的特征提取能力;最后,使用具有双层路由注意力视觉转换器的跨阶段双卷积(cross stage partial with two convolutions and vision transformer of bi-level routing attention, C2BF)模块替换跨阶段双卷积逐点空间注意力(cross stage partial with two convolutions and pointwise spatial attention, C2PSA)模块,提升了算法在复杂环境下对红外图像的检测准确度。结果表明,相较于原始YOLOv11n算法,改进YOLOv11n算法的参数量减少了22.1%;精确率、召回率、平均精确率均值分别达到91.1%、85.5%、90.9%,各自提升了3.0、2.6、2.8个百分点;检测速度达到128.2帧/s。改进YOLOv11n算法能实现对电力设备过热故障红外图像的有效检测,可满足算法轻量化与实时性检测的要求。
文摘Six novel pyrromethene- BF2 complexes,of which five compounds have not been reported,were synthesized and characterized.Their relationships between structure and photophysical behavior were studied with the aid of fluorescence and triplet state absorption spectra.The results indicate that,compared to 8- alkylpyrromethene- BF2 complexes,the compounds containing 8- aryl exhibit high fluorescence quantum yield and rather low triplet state absorption.
