Detect unique molecular structure associated with physiochemical properties in CDC varieties of oat grain with unique nutrient traits [Feed Type vs. Milling Type] in comparison with barley grain using advanced molecular spectroscopy as a non-destructive biological tool

The objective of this study was to determinate grain unique protein inherent molecular structure that are related physiochemical and nutrient profiles in CDC developed oat varieties [CDC Nasser (Feed Type) and CDC Seabiscuit (Milling Type)] grown in cool climate condition in western Canada in comparison with conventional barley variety of CDC Meredith as a control using advanced molecular spectroscopy. Multivariate analyses, including an agglomerative hierarchical cluster analysis (CLA) and principal component analysis (PCA), were performed to identify protein molecular structural differences among the grains. The results revealed that CDC Seabiscuit contained greater (P < 0.05) protein structural Amide I and II than CDC Nasser and CDC Meredith, while the greater (P < 0.005) structural Amide I to II area and height ratios was detected in CDC Meredith. New oat grains had greater (P < 0.05) β-sheet height than barley grains, however, there was no difference in α-helix to β-sheet ratio values among the varieties. In conclusion, CDC Nasser and CDC Meredith had no difference in protein molecular structural features, while CDC Seabiscuit contains different protein structural characteristics as compared to CDC Meredith grain. The molecular structure features are highly associated with physiochemical and nutrient profiles in grains, which indicate that it also affect nutrient utilization and availability.     

Identification of an H1N1 subtype of swine influenza virus and serological analysis

To investigate the epizootic of swine influenza virus(SIV), 60 nasal swabs were collected from a clinical cases of pig farm in Tai'an City, Shandong Province of China in April 2017. SIV was isolated by inoculating into 10-day-old Special Pathogen Free embryonated eggs and the whole genome was sequenced. An H1N1 subtype SIV was isolated and designated as A/swine/Shandong/TA04/2017(H1N1). Phylogenetic analysis showed that apart from the polymerase A(PA) fragment belonging to the 2009 pandemic H1N1 branch, seven genome segments belonged to avian-like H1N1 influenza virus lineage. The cleavage site sequence of the hemagglutinin(HA) protein was PSIQSR↓G, which is a typical molecular biological characteristic. Five potential N-glycosylation sites(N14, N26, N277, N484 and N543) were found in the HA gene. To further investigate the epidemiology of SIV in this farm, the 995 serum samples were assessed with EAH1N1 2009 pandemic H1N1 and H3 N2 antigens. The results showed that the total positive rate was 65.43%. The positive rates of single virus infection detected by EAH1N1, 2009 pdmH1N1 and H3 N2 for serum HI(Hemagglutination inhibition) were 48.35, 30.85 and 7.47%, respectively. The results showed that SIV in Shandong Province has been reassorted in some segments and the SIV-positive rate was high on the SIV outbreak farm. These data provide evidence of an epizootic of SIV.     

园林艺术在现代生态果园中的应用

我国传统的采摘果园仅仅是以“采摘”为主要目的,忽视果园的生态效益,并且没有真正起到陶冶情操、景观观赏的作用。将园林艺术融合到采摘、生态功能为一体的现代生态果园中必将是大势所趋。北京市通州区艺术观光采摘园规划设计就是对于果园艺术表达的探究。     

翅形态特征在重阳木斑蛾成虫性别鉴定中的应用

为了明确重阳木斑蛾的翅形态特征在其性别鉴定中的作用,探索雌雄难于区分的成虫的数值鉴定方法。采用图像处理与分析技术,通过爱普生扫描仪获取重阳木斑蛾前翅图,利用BugShape v1.0软件提取雌雄成虫翅的轮廓特征,利用tpsDig2软件获取翅脉交叉点位置特征,并利用独立样本t检验和标志点空间普氏叠加和扭曲分析,以明确此类特征在该成虫雌雄鉴定中的作用。结果表明,重阳木斑蛾成虫左右前翅轮廓特征在同一性别中差异不显著。仅利用左前翅数据进行分析时,翅面积、短轴长度、等效圆半径、偏心率、球状性和圆形度在两个性别中存在极显著差异,周长和长轴长度的差异达到显著水平,而紧凑度和叶状性差异不显著。使用左右前翅作为数据集进行分析时,除紧凑度和叶状性差异仍不显著外,其余参数均达到极显著水平。雌雄前翅轮廓特征作为指标来判别性别时正确率为100%,但存在左右翅相互错判现象。翅膀内部翅脉交叉点的空间位置在个体间存在较大差异,主要表现在相对于翅的横向方向变异大。雌雄间的差异主要存在于外缘附近的翅脉交叉点。结论:通过前翅的轮廓特征可以区分重阳木斑蛾雌雄成虫的差异。翅脉交叉点空间位置在雌雄间和个体间存在一定的变异。     

极简主义对现代园林艺术的影响

通过对极简主义艺术的起源,特点以及理念的探讨;对极简主义园林东西方渊源的追溯及对现代园林中具有极简主义特征的实例的分析,总结出极简主义艺术在内在文化理念、外在创作形式两个方面对现代园林的影响,指出了学习西方极简主义园林对我国现代园林景观发展的实际意义。     

基于改进YOLO的玉米幼苗株数获取方法

为快速准确获取玉米幼苗株数、评估播种质量、进行查缺补苗等管理,对YOLO算法进行改进,提出了一种基于特征增强机制的幼苗获取检测模型(FE-YOLO),实现了对玉米幼苗株数的快速获取.该方法根据玉米幼苗目标尺寸和空间纹理特征,构建了基于动态激活的轻量特征提取网络,融合了多感受野和空间注意力机制.实验表明:FE-YOLO模...     

基于改进YOLOv4-tiny的茶叶嫩芽检测模型

精准检测茶叶嫩芽是茶叶机械智能采摘的重要前提。针对茶叶大小不一、遮挡造成的小尺度嫩芽特征显著性弱、漏检率高等问题,提出一种基于改进YOLOv4-tiny的茶叶嫩芽检测模型。该模型在颈部网络添加52×52的浅层特征层以提高YOLOv4-tiny网络对小目标嫩芽的关注度,通过引入卷积块注意力机制（Convolutional block attention module,CBAM）以抑制背景噪声,提高嫩芽特征的显著性,采用双向特征金字塔网络（Bidirectional feature pyramid network,BiFPN）以融合不同尺度的特征信息,从而提出一个高性能轻量化的茶叶嫩芽检测模型YOLOv4-tiny-Tea。对同一训练集与测试集进行模型训练与性能测试,结果表明YOLOv4-tiny-Tea模型检测精确率和召回率分别为97.77%和95.23%,相比改进之前分别提高了5.58个百分点和23.14个百分点。消融试验验证了网络结构改进对不同尺度嫩芽检测的有效性,并将改进后的YOLOv4-tiny-Tea模型与3种YOLO系列算法进行对比,发现改进后的YOLOv4-tiny-Tea模型F1值比YOLOv3、YOLOv4、YOLOv5l模型分别提高了12.11、11.66和6.76个百分点,参数量仅为3种网络模型的13.57%、13.06%和35.05%。试验结果表明,YOLOv4-tiny-Tea模型能有效提高不同尺度下嫩芽检测的精确率,大幅度减少小尺寸或遮挡嫩芽的漏检情况,在保持轻量化计算成本的基础上获得较为明显的检测精度,能够满足农业机器人的实时检测和嵌入式开发的需求,可以为茶叶嫩芽智能采摘方法提供参考。     

基于自适应阈值ORB特征提取的果园双目稠密地图构建

针对果园阴暗光照条件下图像特征点匹配数量少、易丢失以及点云稀疏问题,对ORB-SLAM2算法进行了改进,提出了基于自适应阈值ORB特征点提取的果园双目三维地图稠密建图算法。首先在跟踪线程中提出一种自适应阈值的FAST角点提取方法,通过计算不同光照下图像平均像素求解阈值,对左右目图像提取ORB特征,增加了不同光照条件下的特征点匹配数量;然后根据特征点估计相机位姿完成局部地图跟踪,对跟踪线程产生的关键帧地图点进行BA优化完成局部地图构建。在原有算法基础上添加了基于ZED-stereo型相机双目深度融合的稠密建图模块,对左右目关键帧进行特征匹配获得图像对,利用图像对求解深度信息获取地图点,经过深度优化获取相机位姿,根据相机位姿进行局部点云的构建与拼接,最终对获得的点云地图进行全局BA优化,构建果园三维稠密地图。在KITTI数据集序列上进行测试,本文所改进的ORB-SLAM2算法的绝对轨迹误差更加收敛,轨迹误差标准差在00和07序列分别下降60.5%和62.6%,在其他序列上也有不同程度下降,表明本文算法定位精度较原始算法有所提高。不同光照环境下进行算法性能测试,结果表明本文算法较原始算法能更好地适应不同光照条件,在较强光照、正常光照、偏弱光照和阴雨天气下特征点平均匹配数量增加5.32%、4.53%、8.93%、12.91%。进行果园直线和稠密建图试验,结果表明直线行驶偏航角更加收敛,定位精确度高,关键帧提取数量较原始算法下降2.86%、平均跟踪时间减少39.3%;稠密建图效果好,能够很好地反映机器人位姿和果园真实环境信息,满足果园三维稠密点云地图构建需求,可为果园机器人导航路径规划提供支持。     

浅析环境美学对当代园林的启示

在21世纪的美学发展中,环境美学的兴起引起了国际上对"非西方美学"智慧的普遍关注。本文从环境艺术的兴起与园林发展方面论述环境艺术对园林发展的影响与作用。伴随着全球化的进程,环境美学的发展已经成为沟通东西方文化,构建"全球意蕴"的新的园林美学形态的一条新路。