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主流媒体短视频传播中的国家形象建构研究——以中国网短视频节目《中国三分钟(China Mosaic)》为例
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作者 曹晚红 杜潇枭 《武陵学刊》 2024年第6期114-122,140,共10页
以中国网账号发布在境外社交媒体平台Facebook上的节目《中国三分钟(China Mosaic)》为例,使用Python工具软件抓取得到评论数据样本,能很好地分析海外受众对主题类型的关注偏向和态度取向。从整体上看,海外受众对我国国家形象呈现出积... 以中国网账号发布在境外社交媒体平台Facebook上的节目《中国三分钟(China Mosaic)》为例,使用Python工具软件抓取得到评论数据样本,能很好地分析海外受众对主题类型的关注偏向和态度取向。从整体上看,海外受众对我国国家形象呈现出积极认可的态度,主要表现为:高度肯定我国的经济实力和科教发展成果,赞许我大国外交所起到的作用和经济建设成就,向往中华优秀传统文化等。但由于意识形态、东西方认知的差异,在海外受众的评论中也存在一些杂音,需要我们理性对待、主动消弭。在对外传播中,要用海外受众乐于接受的话语表达方式、共通的符号,从大处着眼、小处入手讲述中国故事,掌握议题设置的主动权,传播好中国声音。 展开更多
关键词 主流媒体 国家形象建构 短视频 中国三分钟(China Mosaic)
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煤矿井下无人驾驶轨道电机车障碍物识别 被引量:2
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作者 杨豚 郭永存 +1 位作者 王爽 马鑫 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第1期29-39,共11页
针对现有煤矿井下无人驾驶轨道电机车因巷道环境恶劣导致障碍物识别精度低的问题,提出用于无人驾驶电机车障碍物精准实时检测的PDM-YOLO模型.基于YOLOv5,将模型C3模块中的传统卷积替换为部分卷积,构建C3_P特征提取模块,有效减少模型的... 针对现有煤矿井下无人驾驶轨道电机车因巷道环境恶劣导致障碍物识别精度低的问题,提出用于无人驾驶电机车障碍物精准实时检测的PDM-YOLO模型.基于YOLOv5,将模型C3模块中的传统卷积替换为部分卷积,构建C3_P特征提取模块,有效减少模型的浮点运算量(FLOPs)与计算延迟.采用改进后的解耦头,对传统YOLOv5的预测头进行解耦,提高模型的收敛速度及对障碍物的识别精度.优化Mosaic数据增强方法,丰富训练图像的特征信息,提高模型的普适性和鲁棒性.实验结果表明,PDM-YOLO模型在自制数据集上的平均检测精度(mAP)达到96.3%,平均检测速度达到109.2帧/s,PDM-YOLO模型在PASCAL VOC公共数据集上的检测精度高于现有主流的YOLO系列模型. 展开更多
关键词 无人驾驶电机车 YOLO 障碍物识别 部分卷积 解耦头 Mosaic数据增强
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基于改进YOLOv5m的电动车骑行者头盔与车牌检测方法 被引量:5
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作者 庄建军 叶振兴 《南京信息工程大学学报(自然科学版)》 CAS 北大核心 2024年第1期1-10,共10页
电动车上路必须佩戴安全头盔已成为交管部门的强制性规定.为了能自动检测出电动车骑行者的头盔佩戴情况,提出一种基于改进的YOLOv5m模型的头盔与车牌检测方法,在检测出骑行者未佩戴头盔的同时还能检测出电动车车牌.模型使用自建电动车... 电动车上路必须佩戴安全头盔已成为交管部门的强制性规定.为了能自动检测出电动车骑行者的头盔佩戴情况,提出一种基于改进的YOLOv5m模型的头盔与车牌检测方法,在检测出骑行者未佩戴头盔的同时还能检测出电动车车牌.模型使用自建电动车骑行者头盔与车牌检测数据集进行训练,用DIOU损失函数代替GIOU损失函数,DIOU_NMS代替加权NMS,增强模型对密集骑行场景的识别能力.在Backone部位与预测中小目标的Neck部位加入ECA注意力机制,使得模型对中小目标的识别率有所提高;用K-means算法对锚框尺寸重新进行聚类.最后,改进Mosaic数据增强方式.实验结果表明:改进的YOLOv5m电动车骑行者头盔与车牌检测模型的mAP为92.7%,较原YOLOv5m模型提高2.15个百分点,较YOLOv4-tiny、Faster RCNN模型分别提高5.7个百分点与6.9个百分点.改进后的YOLOv5m模型能有效提高对头盔与车牌的识别率. 展开更多
关键词 头盔检测 车牌检测 YOLOv5m 注意力机制 DIOU K-MEANS算法 改进Mosaic数据增强
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MOSAiC现场观测期间海冰厚度季节变化模拟误差分析
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作者 陆洋 赵海波 +4 位作者 赵嘉炜 王晓春 何宜军 雷瑞波 喻小勇 《海洋学报》 CAS CSCD 北大核心 2024年第6期26-39,共14页
北极气候研究多学科漂流观测计划(Multidisciplinary drifting Observatory for the Study of Arctic Climate, MOSAiC)于2019年10月至2020年9月开展,期间获得了变量完整的大气、海洋、海冰厚度及积雪厚度观测,为海冰模式的发展提供了... 北极气候研究多学科漂流观测计划(Multidisciplinary drifting Observatory for the Study of Arctic Climate, MOSAiC)于2019年10月至2020年9月开展,期间获得了变量完整的大气、海洋、海冰厚度及积雪厚度观测,为海冰模式的发展提供了新的契机。本研究利用两个完整观测时段(2019年11月1日至2020年5月7日、2020年6月26日至7月27日)的大气和海洋强迫场,驱动一维海冰柱模式ICEPACK,模拟了MOSAiC期间海冰厚度的季节演变,同海冰厚度观测进行了对比,并诊断分析了海冰厚度模拟误差的原因。结果表明,在冬春季节,模式可以再现海冰厚度增长过程,但由于模式在春季高估了积雪向海冰的转化及对海冰物质平衡的贡献,模拟的春季海冰厚度偏厚。在夏季期间,2种热力学方案及3种融池方案的组合都表明模式高估了海冰表层的消融过程,导致模拟结束阶段的海冰厚度偏薄。我们的研究表明,使用变量完整的MOSAiC大气和海洋强迫场可以诊断目前海冰模式中的问题,为海冰模式的改进奠定基础。 展开更多
关键词 MOSAiC观测计划 热力学方案 融池方案 ICEPACK海冰模式 海冰厚度 积雪深度 北冰洋
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Development of a stable attenuated double-mutant of tobacco mosaic virus for cross-protection
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作者 Xiaojie Xu Shaoyan Jiang +7 位作者 Chunju Liu Xujie Sun Qing Zhu Xiuzhai Chen Pengchao Jiang Fenglong Wang Yanping Tian Xiangdong Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2318-2331,共14页
Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultiva... Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultivated tobacco and tomato cultivars are susceptible to TMV and there is no effective strategy to control this virus.Cross-protection can be a safe and environmentally friendly strategy to prevent viral diseases.However,stable attenuated TMV mutants are scarce.In this study,we found that the substitutions in the replicase p126,arginine at position 196(R^(196))with aspartic acid(D),glutamic acid at position 614(E^(614))with glycine(G),serine at position 643(S^(643))with phenylalanine(F),or D at position 730(D^(730))with S,significantly reduced the virulence and replication of TMV.However,only the mutation of S^(643) to F reduced the RNA silencing suppression activity of TMV p126.A double-mutant TMV-E614G-S643F induced no visible symptom and was genetically stable through six successive passages in tobacco plants.Furthermore,our results showed that TMV-E614G-S643F double-mutant could provide effective protection against the wild-type TMV infection in tobacco and tomato plants.This study reports a promising mild mutant for cross-protection to control TMV in tobacco and tomato plants. 展开更多
关键词 CROSS-PROTECTION double-mutant p126 tobacco mosaic virus VIRULENCE
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A bacterial protein Rhp-PSP inhibits plant viral proliferation through endoribonuclease activity
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作者 Lijie Chen Qianze Peng +6 位作者 Xiaohua Du Weixing Zhang Ju’e Cheng Shu’e Sun Deyong Zhang Pin Su Yong Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1967-1978,共12页
Plant virus causes massive crop losses globally.However,there is currently no effective measure to control plant viral disease.Previously,we identify an antiviral protein Rhp-PSP,produced by the bacterial Rhodopseudom... Plant virus causes massive crop losses globally.However,there is currently no effective measure to control plant viral disease.Previously,we identify an antiviral protein Rhp-PSP,produced by the bacterial Rhodopseudomonas palustris strain JSC-3b.In this study,we discover that the antiviral activity of Rhp-PSP relies on its endoribonuclease activity.Converting the arginine(R)residue at position 129 onto alanine(A)abolishs its endoribonuclease activity on coat protein(CP)RNA of tobacco mosaic virus(TMV),consequentially,compromises the antiviral activity of Rhp-PSP.Further investigation demonstrates that,the mutant Rhp-PSP^(R129A)is unable to form the homotrimer as the wild type,indicating the importance of quaternary junction for the endoribonuclease activity.Overexpression of Rhp-PSP in Nicotiana benthamiana significantly enhances the resistance against TMV of seedlings,while expression of Rhp-PSP^(R129A)did not,confirming that endoribonuclease activity is responsible for the antiviral activity of Rhp-PSP.In addition,foliar spray of Rhp-PSP solution on tomato and pepper plants significantly reduces the disease index of viral diseases,indicating that Rhp-PSP shows potential to develop antiviral agent in practice. 展开更多
关键词 Rhodopseudomonas palustris Rhp-PSP tobacco mosaic virus ENDORIBONUCLEASE antiviral activity
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CRISPR/CasRx-mediated resistance to Soybean mosaic virus in soybean
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作者 Le Gao Lijun Xie +9 位作者 Yanmin Xiao Xinge Cheng Ruosi Pu Ziheng Zhang Yu Liu Shaopei Gao Zilong Zhang Haoran Qu Haijian Zhi Kai Li 《The Crop Journal》 SCIE CSCD 2024年第4期1093-1101,共9页
Soybean mosaic virus(SMV),an RNA virus,is the most common and destructive pathogenic virus in soybean fields.The newly developed CRISPR/Cas immune system has provided a novel strategy for improving plant resistance to... Soybean mosaic virus(SMV),an RNA virus,is the most common and destructive pathogenic virus in soybean fields.The newly developed CRISPR/Cas immune system has provided a novel strategy for improving plant resistance to viruses;hence,this study aimed to engineer SMV resistance in soybean using this system.Specifically,multiple sgRNAs were designed to target positive-and/or negative-sense strands of the SMV HC-Pro gene.Subsequently,the corresponding CRISPR/CasRx vectors were constructed and transformed into soybeans.After inoculation with SMV,39.02%,35.77%,and 18.70%of T_(1)plants were confirmed to be highly resistant(HR),resistant(R),and mildly resistant(MR)to SMV,respectively,whereas only 6.50%were identified as susceptible(S).Additionally,qRT-PCR and DAS-ELISA showed that,both at 15 and 30 d post-inoculation(dpi),SMV accumulation significantly decreased or was even undetectable in HR and R plants,followed by MR and S plants.Additionally,the expression level of the CasRx gene varied in almost all T_(1)plants with different resistance level,both at 15 and 30 dpi.Furthermore,when SMV resistance was evaluated in the T_(2)generation,the results were similar to those recorded for the T_(1)generation.These findings provide new insights into the application of the CRISPR/CasRx system for soybean improvement and offer a promising alternative strategy for breeding for resistance to biotic stress that will contribute to the development of SMV-immune soybean germplasm to accelerate progress towards greater soybean crop productivity. 展开更多
关键词 SOYBEAN RNA virus Soybean mosaic virus RESISTANCE CRISPR/CasRx
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Intelligent identification method of insulation pull rod defects based on intactness-aware Mosaic data augmentation and fusion of YOLOv5s
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作者 Changyun Li Yuze Hua +2 位作者 Yilin Liu Kai Liu Sanyi Zhang 《High Voltage》 SCIE EI CSCD 2024年第5期1171-1182,共12页
The authors introduce the intactness-aware Mosaic data augmentation strategy,designed to tackle challenges such as low accuracy in detecting defects in insulation pull rods,limited timeliness in intelligent analysis,a... The authors introduce the intactness-aware Mosaic data augmentation strategy,designed to tackle challenges such as low accuracy in detecting defects in insulation pull rods,limited timeliness in intelligent analysis,and the absence of a comprehensive database for information on insulation pull rod defects.The proposed strategy incorporates the YOLOv5s algorithm for detecting defects in insulation pull rods.Initially,the YOLOv5s network was constructed,and a dataset containing photos of insulation pull rods with white spots,fractures,impurities,and bubble flaws was compiled to capture images of defects.The research presented a data enhancement approach to improve the images and establish a dataset for insulation pull rod defects.The YOLOv5s algorithm was applied for both training and testing purposes.A comparative analysis was conducted to assess the detection performance of YOLOv5s against a conventional target detector for identifying defects in insulation pull rods.Furthermore,the utility of Mosaic's data augmentation technique,which incorporates intactness awareness,was evaluated to enhance the accuracy of identifying insulation pull rod defects.The research findings indicate that the YOLOv5s algorithm is employed for intelligent detection and precise localisation of flaws.The intactnessaware Mosaic data augmentation strategy significantly improves the accuracy of detecting faults in insulation pull rods.The YOLOv5s model used achieves a performance index mAP@0.5:0.95 of 0.563 on the test set,distinct from the training set data.With a threshold of 0.5,the mAP@0.5 score is 0.904,indicating a substantial improvement in both detection efficiency and accuracy compared to conventional target detection methods.Innovative approaches for identifying defects in insulation pull rods are introduced. 展开更多
关键词 MOSAIC INSULATION DEFECTS
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Turnip mosaic virus pathogenesis and host resistance mechanisms in Brassica
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作者 Guanwei Wu Xinxin Fang +2 位作者 Tianqi Yu Jianping Chen Fei Yan 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第4期947-960,共14页
Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the... Turnip mosaic virus(TuMV)is a devastating potyvirus pathogen that infects a wide variety of both cultivated and wild Brassicaceae plants.We urgently need more information and understanding of TuMV pathogenesis and the host responses involved in disease development in cruciferous crops.TuMV displays great versatility in viral pathogenesis,especially in its replication and intercellular movement.Moreover,in the coevolutionary arms races between TuMV and its hosts,the virus has evolved to co-opt host factors to facilitate its infection and counter host defense responses.This review mainly focuses on recent advances in understanding the viral factors that contribute to the TuMV infection cycle and the host resistance mechanism in Brassica.Finally,we propose some future research directions on TuMV pathogenesis and control strategies to design durable TuMV-resistant Brassica crops. 展开更多
关键词 Turnip mosaic virus BRASSICA Resistance genes Host factors Infection biology
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一种基于视频的快速图像MOSAICS算法
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作者 解凯 郭恒业 张田文 《计算机工程与应用》 CSCD 北大核心 2002年第6期23-25,共3页
在制作基于视频序列的图像Mosaics时,传统方法都需要将连续相邻帧(偏差小的图像)进行图像整合变换的优化求解。该方法运算量大,速度慢。文章提出一种分步优化求解该变换方法,即渐近复杂模型。它可对偏差较大帧进行自动求解,可大大加速图... 在制作基于视频序列的图像Mosaics时,传统方法都需要将连续相邻帧(偏差小的图像)进行图像整合变换的优化求解。该方法运算量大,速度慢。文章提出一种分步优化求解该变换方法,即渐近复杂模型。它可对偏差较大帧进行自动求解,可大大加速图像Mosaics的制作速度,对快速实时建立图像Mosaics有重大意义。 展开更多
关键词 虚拟现实 视频序列 图像匹配 mosaics算法 图像处理 计算机
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Clinical manifestations and the prenatal diagnosis of trisomy 7 mosaicism:Two case reports
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作者 Fei Hou Yan Li Hua Jin 《World Journal of Clinical Cases》 SCIE 2024年第8期1544-1548,共5页
BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.... BACKGROUND The clinical manifestations of trisomy 7 mosaicism are diverse and nonspecific,so prenatal diagnosis is very difficult.CASE SUMMARY Two pregnant women with abnormal prenatal screening results were included.One was a 22-year-old woman(G1P0).At 31st week of gestation,ultrasound revealed that the posterior horn of the left lateral ventricle was 10 mm and the right renal pelvis had a separation of 7 mm.The other pregnant woman was 33 years old(G2P1L1A0),and her fetus was found to have a cardiac malformation at the 24th week of gestation.Copy number variation sequencing,whole-exome sequencing and karyotype analysis were carried out after amniocentesis,and both fetuses were diagnosed with trisomy 7 mosaicism.After parental counseling,one woman continued the pregnancy,and the other woman terminated the pregnancy.CONCLUSION In trisomy 7 mosaicism,the low proportion of trisomy does not lead to abortion,but can result in abnormal fetal development,which can be detected via ultrasound.Therefore,clinicians need to pay more attention to various aspects of fetal growth and development,combining with imaging,cellular,molecular genetics and other methods to perform comprehensive evaluations of fetuses to provide more reliable genetic counseling for pregnant women. 展开更多
关键词 Trisomy 7 mosaicism Copy number variation sequencing Whole-exome sequencing Karyotype analysis Prenatal diagnosis Case report
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基于改进的Faster RCNN的仪表自动识别方法
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作者 王欣然 张斌 +1 位作者 湛敏 赵成龙 《机电工程》 CAS 北大核心 2024年第3期532-539,共8页
在环境复杂的工业场景中,仪表盘存在类别多、相似性高等问题,导致检测的识别效果较差、准确率不高。针对这一问题,提出了一种基于改进的更快速的区域卷积神经网络(Faster RCNN)的仪表自动识别方法。首先,采用残差网络(Resnet)101代替视... 在环境复杂的工业场景中,仪表盘存在类别多、相似性高等问题,导致检测的识别效果较差、准确率不高。针对这一问题,提出了一种基于改进的更快速的区域卷积神经网络(Faster RCNN)的仪表自动识别方法。首先,采用残差网络(Resnet)101代替视觉几何群网络(VGG)16,进行了网络结构简化;然后,引入了特征金字塔网络(FPN),并将其改进为递归特征金字塔网络后进行了迭代融合,输出了特征图;接着,引入了注意力机制模块,根据特征的重要程度,完成了对输出通道权值的重新分配,增强了Faster RCNN对目标的运算能力;提出了改进非极大值抑制算法(Softer-NMS),通过降低置信度来确定准确的目标候选框;最后,采用Mosaic数据增强技术对可视对象类(VOC)2007数据集进行了扩充,对改进后的Faster RCNN模型进行了仪表自动识别的实验。研究结果表明:在相同工业环境下,与传统的Faster RCNN算法模型相比,改进后的Faster RCNN模型准确率为93.5%,较原模型提高了3.8%,mAP值为92.6%,较原模型提高了3.7%,可见该方法在实际生产中具有较强的鲁棒性与泛化能力,可满足工业上对智能检测的要求。 展开更多
关键词 仪表识别 更快速的区域卷积神经网络 递归特征金字塔网络 注意力机制 非极大值抑制算法 Mosaic数据增强技术
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Enhanced Species Diversity Unlocked by Habitat Conservation in Agricultural Landscapes: New Perspectives on Ecological Weed Management and Sustainable Intensification—Species Diversity and Habitat Conservation
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作者 Michael Ignatius Ferreira 《Open Journal of Ecology》 2024年第8期585-603,共19页
The impulse to remain profitable by increasing agricultural production levels in view of the greater demand for food, provided impetus to production intensification. The aim of this review is to summarise current lite... The impulse to remain profitable by increasing agricultural production levels in view of the greater demand for food, provided impetus to production intensification. The aim of this review is to summarise current literature, reporting specifically on the impact of production intensification on habitats and yield constraints caused by weeds. Secondly, in alleviating these effects over the short term, ecological measures that enhance species diversity in conserved habitats and promote semi-natural habitats in the agricultural landscape, are discussed. In large-scale intensive agriculture, weed control is predominantly rooted in agrochemical applications in the form of herbicides. Long lasting intensive agricultural practices show discord both with the promotion of the biodiversity of microbes belowground and aboveground and with organisms involved in the breaking down of plant material. The presence of native species in the surroundings, in combination with hedgerows and field margins, with a comparatively intricate and balanced variety of plants in a sheltered environment, are essential for settlement of benign insects, particularly in the face of intensive agricultural production. The promising tactic of advantageous seed predators enables decreased herbicide applications. Crop mosaics arranged to advance compatibility at the landscape scale are important to bolster pollination services and insect management, while ecological variety in the surroundings acts as a safety net for habitat diversity. Weed control in combination with different tactics of vegetation use, comprising cover cropping, hedgerows and field margins, sets up safe havens in the landscape, and improves the diffusion of complementary life forms. Field margins perform a meaningful natural function as point of provision for forage, safe havens and distribution passageways for pollinators and insect predators. Production practices that promote more heterogeneity and combine high density semi-natural safe havens and habitat conservation in agro ecosystems are beneficial to species diversity across trophic levels and contribute to agricultural production stability and food safety. 展开更多
关键词 Crop mosaics Field Margins HEDGEROWS Microbial Nitrogen Immobilization Semi-Natural Habitats Soil Microbes Weed Cross-Resistance Weed Seed Predation
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Floristic Diversity, Stand Structure and Plant Life Traits in the Forest-Savanna Mosaic at Ndjole (Centre Cameroon)
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作者 Djeuguen Vanessa Tchaleu Solefack Marie Caroline Momo +3 位作者 Mateso Aimé Kambale Ndondjeu Charles Tafen Yanick Borel Kamga Victor François Nguetsop 《Open Journal of Ecology》 2024年第4期309-330,共22页
With the aim of assessing floristic diversity, stand structure and vegetation ecology, the present work was carried out in the savanna mosaic forest of the locality of Ndjole (Centre Cameroon). A total of 30 floristic... With the aim of assessing floristic diversity, stand structure and vegetation ecology, the present work was carried out in the savanna mosaic forest of the locality of Ndjole (Centre Cameroon). A total of 30 floristic plots of 40 m × 40 m (1600 m<sup>2</sup>) were delineated in the different ecosystems (forest, forest-savanna contact zone and the savanna). Within each plot, all individuals with a diameter at breast height ≥ 10 cm at 1.30 m were taken into account. ANOVA was used to compare the means of the diversity indices of the different ecosystems, and the DUNCAN test at 5% significance level (XLSTAT 2016) to separate these means. A total of 85 species belonging to 67 genera and 33 families were recorded. That is, 68 species in semi-caducifolia forest, 45 in forest-savanna contact zone and 18 in savanna. Urticaceae, Combretaceae, Apocynaceae, Myristicaceae and Euphorbiaceae are the most diverse families in the forest. On the other hand, in contact zones, the Euphorbiaceae, Fabaceae, Annonaceae and Moraceae families are the most diversified, while in the savannas, the Combretaceae, Fabaceae and Annonaceae families are the most diversified. Shannon’s diversity index values (1.7 to 2.37 bits) reflect low specific diversity;Piélou’s equitability (0.86 to 0.9) shows good distribution of individuals within species. The diametric structure of woody species shows an inverted “J” shape in all plant communities. This indicates a high regeneration potential characterized by a greater number of small trees than large trees. Mesophanerophytes and megaphanerophytes are dominant in forests and forest-savanna contact zones, and microphanerophytes in the savannas. Endozoochory is the main mode of diaspore dissemination. As regards the distribution of phytogeographical types, it shows the overall dominance of Guineo-Congolese species in all plant communities. Our study provides detailed data on forest-savanna floristic and plant life traits in the mosaic and recommends further studies on the impact of environmental parameter variations on the forest encroachment into savanna. 展开更多
关键词 MOSAIC COMMUNITIES DISSEMINATION Regeneration Diversity
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Reactions of Maruca Resistant Transgenic Cowpea to Cowpea Aphid-Borne Mosaic Virus
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作者 Mounyratou Rabo Moustapha Ouédraogo +6 位作者 Orokia Coulibaly Assita Traoré-Barro Salimata Traoré Teyioue Benoit Joseph Batieno Chantal Kaboré-Zoungrana Aboubacar Toguyeni Oumar Traoré 《Agricultural Sciences》 2024年第7期742-753,共12页
Cowpea (Vigna unguiculata L. [Walp.]) in one of the main grain legumes contributing to food security and poverty alleviation in Sub-Saharan Africa. To control the highly damaging legume pod borer Maruca vitrata F., tr... Cowpea (Vigna unguiculata L. [Walp.]) in one of the main grain legumes contributing to food security and poverty alleviation in Sub-Saharan Africa. To control the highly damaging legume pod borer Maruca vitrata F., transgenic cowpea lines expressing the insecticidal Cry1Ab Bt protein were developed. In this study, we evaluated the impact of Cry1Ab transgene expression on the susceptibility of four cowpea lines (named IT97K-T, IT98K-T, Gourgou-T and Nafi-T) and their respective non-transgenic near isogenic lines (IT97K, IT98K, Gourgou and Nafi) to Cowpea aphid-borne mosaic virus (CABMV) in greenhouse conditions. In a preliminary quality control test by enzyme-linked immunosorbent assay, the presence of Cry1Ab protein in transgenic seed lots ranged from 59% to 72%, with no significant differences among the lines (χ2 = 3.26;p = 0.35). Upon virus inoculation, all cowpea lines exhibited mosaic symptoms with similar severity between 7- and 11-day post-inoculation. No significant differences were observed in symptom severity. Significant differences were found between cowpea lines for time of symptom onset, virus accumulation in plants and days to 50% flowering. However, while comparing pairs of transgenic lines and corresponding non-transgenic lines, virus accumulation showed not significant differences whatever the pair. Time of symptom onset and days to 50% flowering did not also differ significantly between pairs of cowpea lines except Nafi/Nafi-T in which transgenic Nafi-T showed earlier symptoms (7.4 ± 0.7 vs. 8.9 ± 0.8 days post-inoculation) and shorter flowering time (37.3 ± 0.6 vs. 42 ± 1.7 days after sowing). Overall, these findings improve our understanding of the effects of Cry1Ab gene mediated genetic modification on cowpea infection by Cowpea aphid-borne mosaic virus, with potential implications for environmental safety assessment. 展开更多
关键词 COWPEA CRY1AB Cowpea Aphid-Borne Mosaic Virus Environmental Safety
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iDEAL-CIO: Instant Digital Express Advocated “Magic Lamp” for Cloud Intelligence Outlet
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作者 Sheldon Liang Paul Anthony Miller +1 位作者 Brendan Shane Rowe Alexis Rainbow 《Intelligent Information Management》 2024年第1期35-63,共29页
Instant Digital Express iDEAL-CIO The “Magic Lamp” for Cloud Intelligence Outlet, which has been recommended, combines innovations to satisfy modern users’ needs and efficiently sift through the ever-expanding amou... Instant Digital Express iDEAL-CIO The “Magic Lamp” for Cloud Intelligence Outlet, which has been recommended, combines innovations to satisfy modern users’ needs and efficiently sift through the ever-expanding amount of intelligent content stored in the cloud. One such innovation introduces a ground-breaking concept to remove superfluous and outdated sequential search patterns that overwhelm the user and computer in order to better serve the user in an eclectic & elastic and multidimensional approach to finding, grouping, assimilation, organizing, and delivering archival content. The cloud intelligence outlet (CIO) is presented in this article as the perfect magic lamp option for quick digital express advocacy. The grouping, indexing, folding, and targeting (GIFT) method of multidimensional online synthetic/analytical intelligent content (MOSAIC) for adaptive intelligence is the fundamental intelligent aggregation and automated process of the Magic Lamp. Three perspectives above this new ideal framework are available to observe: The Magic Lamp proposes contextual and multiple analytical tracks to improve cloud intelligence services conceptually. Technically speaking, MOSAIC combines domain-specific services for a wide range of international users, and through the usage of Cloud Intelligence Outlet, GIFT operationally activates grouping, indexing, folding, and targeting to promote decent experience and in-depth research on target for users’ wants. Because of this, iDEAL-CIO works in tandem with cloud extraction, digital transformation, and archival loading to provide improved service through the readily accessible cloud intelligence outlet. 展开更多
关键词 iDEAL-CIO MOSAIC Multidimensional Online Synthetic/Analytical Intelligent Content
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基于改进YOLOv8算法的草莓采摘目标检测算法
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作者 赵艳芹 崔翊超 《高师理科学刊》 2024年第10期46-51,共6页
针对农业领域中草莓采摘机器人在复杂环境下识别草莓果实准确率不高的问题,提出了一种基于改进后的YOLOv8算法的解决方案,该方法能够实现对草莓果实的精确、快速识别.首先,使用Mosaic数据增强算法进行目标检测数据预处理,该方法显著提... 针对农业领域中草莓采摘机器人在复杂环境下识别草莓果实准确率不高的问题,提出了一种基于改进后的YOLOv8算法的解决方案,该方法能够实现对草莓果实的精确、快速识别.首先,使用Mosaic数据增强算法进行目标检测数据预处理,该方法显著提高了模型的泛化能力,并帮助模型在复杂背景中更好地识别草莓;其次,引入了通道优先卷积注意力机制,该机制通过重点关注图像中的信息丰富通道,提高了对小目标草莓的检测能力,显著提升了特征提取的效率,使得模型能够更加集中地学习和提取与草莓识别相关的特征,从而提高了小目标检测的精度.通过一系列的实验验证,改进后的YOLOv8算法在草莓采摘目标检测中的表现显著优于原始YOLOv8算法,其平均精度均值达到89.35%,相较于原YOLOv8算法,平均精度均值提升了5.83%.综上所述,所提出方法在识别草莓果实时具有显著的优势,特别是在处理小目标和复杂背景方面.改进后的YOLOv8-ECPCA网络模型达到了可在草莓采摘机器人中应用的水平,可为采摘机器人在实际农业环境中的实时小目标检测提供强有力的支持. 展开更多
关键词 采摘机器人 YOLOv8算法 注意力机制 Mosaic数据增强算法
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Web-based interactive visualization of 3D video mosaics using X3D standard 被引量:2
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作者 CHON Jaechoon LEE Yang-Won SHIBASAKI Ryosuke 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第7期1259-1265,共7页
We present a method of 3D image mosaicing for real 3D representation of roadside buildings, and implement a Web-based interactive visualization environment for the 3D video mosaics created by 3D image mosaicing. The 3... We present a method of 3D image mosaicing for real 3D representation of roadside buildings, and implement a Web-based interactive visualization environment for the 3D video mosaics created by 3D image mosaicing. The 3D image mo- saicing technique developed in our previous work is a very powerful method for creating textured 3D-GIS data without excessive data processing like the laser or stereo system. For the Web-based open access to the 3D video mosaics, we build an interactive visualization environment using X3D, the emerging standard of Web 3D. We conduct the data preprocessing for 3D video mosaics and the X3D modeling for textured 3D data. The data preprocessing includes the conversion of each frame of 3D video mosaics into concatenated image files that can be hyperlinked on the Web. The X3D modeling handles the representation of concatenated images using necessary X3D nodes. By employing X3D as the data format for 3D image mosaics, the real 3D representation of roadside buildings is extended to the Web and mobile service systems. 展开更多
关键词 3D video mosaics Interactive 3D visualization Web 3D
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On Evolutionary Sequence Systematics: Taking Permian Waagenophylloid Coral Fauna as an Example 被引量:2
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作者 Xu Guirong Gong Shuyun Wang Yongbiao(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) 《Journal of Earth Science》 SCIE CAS CSCD 1999年第3期215-227,共13页
Evolutionary sequence systematics is a discipline in paleontology and biology that deals with phylogeny of organism, the main purpose of which is to understand relatives between species and taxa and to show their evol... Evolutionary sequence systematics is a discipline in paleontology and biology that deals with phylogeny of organism, the main purpose of which is to understand relatives between species and taxa and to show their evolutionary sequence. The systematics is set up on the phenetic-cladistic systematics. A number of important theoretical concepts in the cladistics are added the concept of time in the systematics. For example, the time-span between the closest sister species is considered limited in the duration of their mother species. The foundational methodology of the systematics is to analyze sister-group and character mosaic distribution, and the key to study evolutionary sequence is to understand cbaracter mosaic distribution fully. These aualyses can be executed by using computer. In the paper, the Permian Waagenophylloid coral fauna is taken as an example to illustrate the analysis on evolutionary sequence. These coral fossils are widespread in Tethyan area.Seventeen characters and a number of cbaracter states for each character used in study result from features of Waagenophylloid corals. According to principles of tbe widest distribution of character states, fossil records and ontogenesis we discerned plesiomorph character states for each character. Characters are divided into 4 ranks on the basis of their important place in pkylogeny. Based on the theory and methopology of tbe evolutionary sequence systematics the paper analyzes the sister groups and evolutionary sequence. In the examination each other between the analyses of sister groups and evolutionary sequence tbe paper found many importunt phenomena of paleontology,such as character degeneration, parallel evolution, and polydirectional clades, and distinguished a number of abnormal order. Iu the discussion to test tke rirst occurrence event8 of biostratigraphy we infer the Possible stratigraphic levels of some fossils. 展开更多
关键词 evolutionary sequence systematics character mosaic distribution Permian Waagenophylloid corals
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Farmer's Adaptive Strategies on Land Competition between Societal Outcomes and Agroecosystem Conservation in the Purple-soiled Hilly Region,Southwestern China 被引量:3
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作者 TANG Qiang BAO Yuhai +2 位作者 HE Xiubin ZHU Bo ZHANG Xinbao 《Journal of Mountain Science》 SCIE CSCD 2012年第1期77-86,共10页
The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions ... The worldwide extension and intensification of farming during the last century has led to ecosystem degradation and caused a series of environmental problems.Conservation of ecosystem services in agricultural regions has been implemented by top-down government actions or initiated by resilience scientists in the developed countries,but little attention was paid in the developing countries,especially in some remote mountainous regions.The present paper presents a case study showing how local farmers obtained both maximal societal outcomes and agroecosystem conservation interests in the absence of distinct boundaries between agricultural and protected ecological areas in the densely populated purple-soiled hilly region of southwestern China.The local community(Yanting County) has developed a mosaic agricultural-forestry-fishery-stock breeding system with spatially targeted land uses,diverse agricultural productions and multiple ecological partnerships.It indicates that the local farmers have hereditarily perceived sound strategies on maximizing sustainable societal outcomes and optimizing tradeoffs among macro-market,state policy,new technological facility and ecological reinforcement. 展开更多
关键词 Mosaic agroforestry system Adaptive strategies Land competition Agroecosystem conservation Purple-soiled hilly region China
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