In this paper, the X-ray nondestructive test method of small defects in precision weldments with complex structure was presented. To resolve the difficulty of defect segmentation in variable grey image, the image proc...In this paper, the X-ray nondestructive test method of small defects in precision weldments with complex structure was presented. To resolve the difficulty of defect segmentation in variable grey image, the image processing based on Visual Basic programming method was adopted. The methods of automatic contrast and partial grey stretch were used to enhance the X-ray detection image which has relatively low contrast, then automatic threshold method was carried out to segment the two high intensity zones, and weld zones which contain the small defects was extracted. Smoothing and sharpen processing were proceeded on the extracted weld zones, and small defects in X-ray detection image of weldments with complex structure were segmented by using the method of background subtraction in the end. The effects of raster were eliminated, and because of that the image processing was only proceeded on the extracted weld zones, the calculated speed using the above provided algorithm was improved.展开更多
试验旨在探究燕麦饲喂条件下断奶马驹十二指肠、空肠和回肠内容物细菌丰度的变化,为通过营养方式调节肠道微生物,增强马驹肠道健康提供参考依据。选择出生日期和断奶日期相近、体重为(112.36±7.50)kg的哈萨克马公驹5匹,在相同的饲...试验旨在探究燕麦饲喂条件下断奶马驹十二指肠、空肠和回肠内容物细菌丰度的变化,为通过营养方式调节肠道微生物,增强马驹肠道健康提供参考依据。选择出生日期和断奶日期相近、体重为(112.36±7.50)kg的哈萨克马公驹5匹,在相同的饲养管理和日粮营养水平条件下,进行为期60 d的饲养。于试验最后1 d进行屠宰,分别采集马驹十二指肠、空肠和回肠的内容物,利用16S r DNA高通量测序技术检测各肠段内容物细菌多样性。结果表明:(1)十二指肠、空肠和回肠内容物菌群中共有OTU为1389个,特有的OTU数量分别为360、318和249个,各肠段内容物菌群的Chao1、ACE、Shannon和Simpson指数无差异显著性(P>0.05);(2)马驹各肠段内容物10大优势菌门分别为厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、螺旋菌门(Spirochaetes)、放线菌门(Actinobacteria)、疣微菌门(Verrucomicrobia)、纤维杆菌门(Fibrobacteres)、软壁菌门(Tenericutes)、Melainabacteria和蓝藻(Cyanobacteria);10大优势菌科为毛螺旋菌科(Lachnospiraceae)、肠杆菌科(Enterobacteriaceae)、链球菌科(Streptococcaceae)、未经确认的梭菌科(unidentified_Clostridiales)、瘤胃球菌科(Ruminococcaceae)、毛螺菌科(Lachnospiraceae)、普雷沃氏菌科(Prevotellaceae)、巴斯德氏菌科(Pasteurellaceae)、理研菌科(Rikenellaceae)和明串珠菌科(Leuconostocaceae);10大优势菌属为乳杆菌属(Lactobacillus)、未经确认的肠杆菌属(unidentified_Enterobacteriaceae)、链球菌属(Streptococcus)、乳球菌属(Lactococcus)、未经确认的梭菌属(unidentified_Clostridiales)、八叠球菌属(Sarcina)、柠檬酸杆菌属(Citrobacter)、放线杆菌属(Actinobacillus)、魏斯氏菌属(Weissella)和未经确认的瘤胃球菌属(unidentified_Ruminococcaceae)。(3)除空肠内容物中普雷沃氏菌科高于回肠135.96%外(P<0.05),其余优势菌在门、科、属水平均无差异显著性(P>0.05)。(4)LEFSe分析中,十二指肠、空肠和回肠肠道内容物菌群之间存在显著差异的菌有11种。其中,十二指肠内容物中显著上调的菌8种,空肠内容物显著上调的菌1种,回肠内容物显著上调的菌2种;功能预测出25种功能。综上所述,燕麦饲喂条件下,断奶马驹十二指肠、空肠和回肠内容物菌群多样性指数没有显著性变化;在细菌种类和相对丰度方面,排名在前的10大优势菌种类一致,但十二指肠内容物与空肠和回肠相比,存在较多的差异显著菌,且细菌功能具有区域特异性,导致各肠段微生物的功能不尽相同。展开更多
文摘In this paper, the X-ray nondestructive test method of small defects in precision weldments with complex structure was presented. To resolve the difficulty of defect segmentation in variable grey image, the image processing based on Visual Basic programming method was adopted. The methods of automatic contrast and partial grey stretch were used to enhance the X-ray detection image which has relatively low contrast, then automatic threshold method was carried out to segment the two high intensity zones, and weld zones which contain the small defects was extracted. Smoothing and sharpen processing were proceeded on the extracted weld zones, and small defects in X-ray detection image of weldments with complex structure were segmented by using the method of background subtraction in the end. The effects of raster were eliminated, and because of that the image processing was only proceeded on the extracted weld zones, the calculated speed using the above provided algorithm was improved.
文摘试验旨在探究燕麦饲喂条件下断奶马驹十二指肠、空肠和回肠内容物细菌丰度的变化,为通过营养方式调节肠道微生物,增强马驹肠道健康提供参考依据。选择出生日期和断奶日期相近、体重为(112.36±7.50)kg的哈萨克马公驹5匹,在相同的饲养管理和日粮营养水平条件下,进行为期60 d的饲养。于试验最后1 d进行屠宰,分别采集马驹十二指肠、空肠和回肠的内容物,利用16S r DNA高通量测序技术检测各肠段内容物细菌多样性。结果表明:(1)十二指肠、空肠和回肠内容物菌群中共有OTU为1389个,特有的OTU数量分别为360、318和249个,各肠段内容物菌群的Chao1、ACE、Shannon和Simpson指数无差异显著性(P>0.05);(2)马驹各肠段内容物10大优势菌门分别为厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、螺旋菌门(Spirochaetes)、放线菌门(Actinobacteria)、疣微菌门(Verrucomicrobia)、纤维杆菌门(Fibrobacteres)、软壁菌门(Tenericutes)、Melainabacteria和蓝藻(Cyanobacteria);10大优势菌科为毛螺旋菌科(Lachnospiraceae)、肠杆菌科(Enterobacteriaceae)、链球菌科(Streptococcaceae)、未经确认的梭菌科(unidentified_Clostridiales)、瘤胃球菌科(Ruminococcaceae)、毛螺菌科(Lachnospiraceae)、普雷沃氏菌科(Prevotellaceae)、巴斯德氏菌科(Pasteurellaceae)、理研菌科(Rikenellaceae)和明串珠菌科(Leuconostocaceae);10大优势菌属为乳杆菌属(Lactobacillus)、未经确认的肠杆菌属(unidentified_Enterobacteriaceae)、链球菌属(Streptococcus)、乳球菌属(Lactococcus)、未经确认的梭菌属(unidentified_Clostridiales)、八叠球菌属(Sarcina)、柠檬酸杆菌属(Citrobacter)、放线杆菌属(Actinobacillus)、魏斯氏菌属(Weissella)和未经确认的瘤胃球菌属(unidentified_Ruminococcaceae)。(3)除空肠内容物中普雷沃氏菌科高于回肠135.96%外(P<0.05),其余优势菌在门、科、属水平均无差异显著性(P>0.05)。(4)LEFSe分析中,十二指肠、空肠和回肠肠道内容物菌群之间存在显著差异的菌有11种。其中,十二指肠内容物中显著上调的菌8种,空肠内容物显著上调的菌1种,回肠内容物显著上调的菌2种;功能预测出25种功能。综上所述,燕麦饲喂条件下,断奶马驹十二指肠、空肠和回肠内容物菌群多样性指数没有显著性变化;在细菌种类和相对丰度方面,排名在前的10大优势菌种类一致,但十二指肠内容物与空肠和回肠相比,存在较多的差异显著菌,且细菌功能具有区域特异性,导致各肠段微生物的功能不尽相同。
