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Reconfigurable Vortex-like Paramagnetic Nanoparticle Swarm with upstream Motility and High Body-length Ratio Velocity

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Research 2023年第4期2023卷 361-377页

作者： Luyao Wang Han Gao Hongyan Sun Yiming Ji Li Song Lina Jia Chutian Wang Chan Li Deyuan Zhang Ye Xu Huawei Chen Lin Feng School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing 100191China Center of Soft Matter Physics and Its Applications Beihang UniversityBeijing 100191China.

Drug delivery systems with high-targeted doses can minimize excipients,reduce side effects,and improve efficacy.Human blood circulation is a complex circulatory system,and the motion control of microrobots in the static flow field in vitro is completely different from in vivo.How to achieve precise counterflow motion for targeted drug delivery without vascular blockage and immune rejection is the biggest challenge for micro-nano robots.Here,we propose a control method that enables vortex-like paramagnetic nanoparticle swarm(VPNS)to move upstream against the flow.By mimicking the clustering motion of wild herring schools and the rolling of leukocytes,VPNS are incredibly stable even when subjected to high-intensity jet impacts in the blood environment,can travel upstream,anchor at the target location,and dissipate when the magnetic field is withdrawn,which greatly reduces the risk of thrombosis.VPNS can also upstream along the vessel wall without an additional energy source and has a marked targeted therapeutic effect on subcutaneous tumors.

关键词： magnetic Velocity upstream

PbEIL1 acts upstream of PbCysp1 to regulate ovule senescence in seedless pear

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Horticulture Research 2021年第1期8卷 818-829页

作者： Huibin Wang Haiqi Zhang Fangfang Liang Liu Cong Linyan Song Xieyu Li Rui Zhai Chengquan Yang Zhigang Wang Fengwang Ma Lingfei Xu College of Horticulture Northwest A&F UniversityYanglingShaanxi ProvinceChina

Numerous environmental and endogenous signals control the highly orchestrated and intricate process of plant senescence.Ethylene,a well-known inducer of senescence,has long been considered a key endogenous regulator of leaf and flower senescence,but the molecular mechanism of ethylene-induced ovule senescence has not yet been elucidated.In this study,we found that blockage of fertilization caused ovule abortion in the pear cultivar‘1913’.According to transcriptome and phytohormone content data,ethylene biosynthesis was activated by pollination.At the same time,ethylene overaccumulated in ovules,where cells were sensitive to ethylene signals in the absence of fertilization.We identified a transcription factor in the ethylene signal response,ethylene-insensitive 3-like(EIL1),as a likely participant in ovule senescence.Overexpression of PbEIL1 in tomato caused precocious onset of ovule senescence.We further found that EIL1 could directly bind to the promoter of the SENESCENCE-ASSOCIATED CYSTEINE PROTEINASE 1(PbCysp1)gene and act upstream of senescence.Yeast one-hybrid and dual-luciferase assays revealed the interaction of the transcription factor and the promoter DNA sequence and demonstrated that PbEIL1 enhanced the action of PbCysp1.Collectively,our results provide new insights into how ethylene promotes the progression of unfertilized ovule senescence.

关键词： endogenous senescence upstream

Artificial intelligence in oil and gas upstream: Trends, challenges, and scenarios for the future

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能源与人工智能(英文)

能源与人工智能(英文) 2021年第1期3卷 73-82页

作者： Dmitry Koroteev Zeljko Tekic Skolkovo Institute of Science and Technology Russian Federation Digital Petroleum LLC Russian Federation

We analyze how artificial intelligence changes a significant part of the energy sector,the oil and gas industry.We focus on the upstream segment as the most capital-intensive part of oil and gas and the segment of enormous uncertainties to tackle.Basing on the analysis of AI application possibilities and the review of existing applica-tions,we outline the most recent trends in developing AI-based tools and identify their effects on accelerating and de-risking processes in the industry.We investigate AI approaches and algorithms,as well as the role and availability of data in the segment.Further,we discuss the main non-technical challenges that prevent the in-tensive application of artificial intelligence in the oil and gas industry,related to data,people,and new forms of collaboration.We also outline three possible scenarios of how artificial intelligence will develop in the oil and gas industry and how it may change it in the future(in 5,10,and 20 years).

关键词： Artificial Intelligence Digital transformation Oil and gas industry upstream Innovation

Trends in the upstream Business Strategic Adjustment of International Oil Companies

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China Oil & Gas 2019年第6期26卷 45-52页

作者： Hou Mingyang Natural Gas Strategic Research Center Sinopec Petroleum Exploration and Production Research Institute

Since 2014, in order to cope with changes in the international oil market, the international oil giants have dynamically adjusted their upstream development strategies, including continuously promoting the "increase in reserves and production", steadily realising "cost reduction and efficiency increase", identifying future development areas, and focusing on overseas business areas. In this process, the international oil giants have implemented upstream strategic adjustment, achieving sound results. First, they have strengthened exploration to obtain oil and gas resources at a lower cost;second, they have implemented M&A and divestiture to optimize their upstream asset portfolios;third, they have strengthened cooperation with resource countries to avoid risks;and fourth, they have attached importance to technology and management innovation in order to improve efficiency. For Chinese oil enterprises, the trends and paths of the upstream strategic adjustment of international oil giants can provide valuable references. Chinese oil enterprises should attach importance to the study of upstream strategies. They should research both the strategic and tactical levels to provide a guarantee for defining the upstream strategy most suitable for their own development. In addition, they should learn from the existing experience of the upstream strategic adjustment of international oil giants in order to support the continuous improvement of the quality and efficiency of their upstream development.

关键词： strengthened upstream giant

Bacterial Community Structure of Sediment in upstream Ecological Wetland of Guanting Reservoir under the Action of Different Plants in Winter

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Meteorological and Environmental Research 2019年第1期10卷 46-48,51页

作者： Yan Donghua Jiang Tiantian Li Hongbo Zhai Xuezheng Wang Mengyao Wang Jianghua Zhao Jianguo Institute of Green Development Hebei Provincial Academy of Environmental Sciences Institute of Water Environment Science Hebei Provincial Academy of Environmental Sciences Baoding Institute of Environmental Protection

In order to study the effect of reed and cattail on the bacterial community structure of surface sediments of wetland in winter,highthroughput sequencing technology was used to analyze the bacterial composition. The results showed that 134 228 high-quality gene sequences were obtained by high-throughput sequencing in sediments of natural wetland in winter,and there were 13 866 OTUs,in which the number of OUT in sediments of reed wetland and cattail wetland was 6 677 and 7 189 respectively. The richness and diversity of bacterial communities in sediments of cattail wetland in winter were higher than those in sediments of reed wetland. Relative abundance of Proteobacteria in sediments of reed wetland and cattail wetland was 0. 54 and 0. 52,respectively. The dominant classes of bacteria were Betaproteobacteria,Deltaproteobacteria,Gammaproteobacteria and Epsilonproteobacteria,which belonged to gram-negative bacteria,indicating that the rhizosphere of wetland was easier to enrich gram-negative bacteria. Under the genus level,the dominant bacteria in the sediments were not obvious.

关键词： High-throughput sequencing Bacterial community Sediment Winter upstream ecological wetland of Guanting Reservoir

MIIT Convened Work Meeting for upstream and Downstream Cooperation Mechanism of Aluminum Material For Civilian Aircraft

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China Nonferrous Metals Monthly 2015年第10期 9-10页

On September 15,2015,the Department of Raw Material Industry and the Department of Equipment Industry of the Ministry of Industry and Information Technology(MIIT)jointly organized and convened the first work meeting for upstream and downstream cooperation mechanism of aluminum material for civilian aircraft in Shanghai.Entrusted by

关键词： cooperation downstream aircraft upstream jointly o

Sinopec Is Eager for upstream Resources

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China Chemical Reporter 2009年第Z1期20卷 9-9页

Sinopec Group’s source said on February 4th theoil group is in talks to purchase a 20% interest inRepsol YPF,a Spanish oil company,from Span-ish builder Sacyr Vallenhermoso.The move is to strengthen Sinopec’s

关键词： Spanish purchase upstream builder strengthen signe

Study on Strip-shaped City Agglomeration in upstream Area of Yellow River

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China City Planning Review 2007年第1期16卷 40-48页

作者： LI Mingji, Lecturer, College of Resources and Environment, Ningxia University, Yinchuan, P. R. China. SHI Peiji, Professor, Dean of College of Geography and Environment, Northwest Normal University, Lanzhou, P. R. China.QIAN Fang

As a new kind of spatial structure, the strip-shaped city agglomeration has been concerned by the academic world – . There are many studies focusing on the spatial structure of city agglomerations in the developed ar... 详细信息

关键词： shaped agglomeration upstream Lanzhou concerned Ba

THE DRIVING FORCES OF LAND USE/COVER CHANGE INTHE upstream AREA OF THE NENJIANG RIVER

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Chinese Geographical Science 2001年第4期11卷 91-95页

作者： YE Bao-ying1, HUANG Fang2 , ZHANG Shu-wen1, ZHANG Yang-zhen1( 1. Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China 2. College of Urban and Environmental Sciences, Northeast Normal Univers

ABSTRACT: Based on the Landsat 5 and Landsat 7 TM images, the land use/cover change was detected in the upstream area of the Nenjiang River between 1995 and 2000. With the spatial analysis techniques of GIS, the maps of land use degree and its change within this period were produced. To identify the causes of changes, elevation and slope were regarded as the main natural influencing factors and were transformed from coverage format to grid format within GIS. The Thiesson polygon method was used to the spatial allocation of socio-economic factors including human population, livestock numbers, mechanizing power of farming and the nearest distance from the changed pixel to the trunk stream and to main settlements, thereby the spatial relationship between land use degree change and socio-economic factor variation was analyzed. According to results of the spatial correlation, the determinants of changes in land use/cover, i. e. elevation, slope, population density change, livestock increase were extracted quantitatively in this area. At last, the spatial multi-linear regression model of land use degree change was developed as follows: △ La = 11. 037-4. 512 * eleva-tion-0. 298 * slope + 0. 292 *△ population + 2. 596 *△ livestock.

关键词： KEYWORDS: the upstream area of the Nenjiang River land use degree change Thiesson polygon method drivingforces