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Advance on large scale near-duplicate video retrieval

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Frontiers of Computer Science 2020年第5期14卷 1-24页

作者： ling shen Richang Hong Yanbin Hao School of Computer Science and Information Engineering Hefei University of TechnologyHefei230009China Department of Computer Science City University of Hong KongHong Kong999077China

Emerging Internet services and applications attract increasing users to involve in diverse video-related activities,such as video searching,video downloading,video sharing and so *** normal operations,they lead to an explosive growth of online video volume,and inevitably give rise to the massive near-duplicate ***-duplicate video retrieval(NDVR)has always been a hot *** primary purpose of this paper is to present a comprehensive survey and an updated review of the advance on large-scale NDVR to supply guidance for ***,we summarize and compare the definitions of near-duplicate videos(NDVs)in the literature,analyze the relationship between NDVR and its related research topics theoretically,describe its generic framework in detail,investigate the existing state-of-the-art NDVR ***,we present the development trends and research directions of this topic.

关键词： near-duplicate videos video retrieval feature representation video signature indexing similarity measurement

Enantiomer-selective Living Polymerization of rac-Phenyl Isocyanide Using Chiral Palladium Catalyst

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Chinese Journal of Polymer Science 2018年第7期36卷 799-804页

作者： Jian Huang ling shen Hui Zou Na Liu Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Hefei University of Technology and Anhui Key Laboratory of Advanced Catalytic Materials and Reaction Engineering

We report the polymerization of phenyl isocyanides with the chiral palladium（II） initiating system. The resulting polymers with optically active properties were obtained by polymerization of the racemic isocyanide monomer （rac-1）, and enantiomerically unbalanced polymerization of the monomer was found, providing substantial evidence for the enantiomer-selective polymerization of rac- 1 mediated through chiral catalyst. A comparison between the enantiomerically pure monomers, 4-isocyanobenzoyl-L-alanine decyl ester （1 s） and 4-isocyanobenzoyl-D-alanine decyl ester （1 r）, revealed a drastic discrepancy in the reactivity ratio of their homopolymerizations. It turned out that the monomer reactivity ratio of ls was higher than that of lr with chiral ligands. The results clearly demonstrated the inclination for incorporation of the ls enantiomer during the polymerization process and thus resulted in the enantiomer-selective polymerization in this system. The effects of the catalyst chirality on the optically active properties of polymerization were investigated, and it was concluded that the formation of higher-ordered conformation with a handed helicity might be attributed to the chiral induction of chiral palladium（II） catalyst. Moreover, the polymers obtained through the enantiomer-selective polymerization of the enantiomerically pure monomer were with a significant improvement of the optical activity if the chirality of the monomer and the catalyst matched with each other.

关键词： Enantiomer-selective polymerization Kinetic resolution Chiral sulfinamide bisphosphine Polyisocyanides Living polymerization

COVID-19 in children and the importance of COVID-19 vaccination

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World Journal of Pediatrics 2021年第5期17卷 462-466页

作者： Feng-Xia Xue Kun-ling shen Department of Respiratory Medicine Beijing Children's HospitalChina National Clinical Research Center of Respiratory DiseasesNational Center for Children's HealthCapital Medical UniversityBeijing 100045China

As of August 30,2021,COVID-19 has caused more than 216 million infections and 4.49 million deaths worldwide,with 0.58 million new cases[1].Because the COVID-19 vaccine is distributed gradually and widely,the development of the global epidemic has been prevented to some extent,but the emergence of SARS-CoV-2 variants makes us *** alpha(B.1.1.7),beta(B.1.351),gamma(P.1)and delta(B.1.617)strains have been named variants of concern by the WHO[2].The SARS-CoV-2 variants have increased in transmissibility and virulence,leading to higher morbidity and mortality.

关键词： COV milli delta

Diagnosis and treatment of 2019 novel coronavirus infection in children: a pressing issue

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World Journal of Pediatrics 2020年第3期16卷 219-221页

作者： Kun-ling shen Yong-Hong Yang China National Clinical Research Center for Respiratory Diseases BeijingChina Department of Respiratory Medicine Beijing Children's HospitalCapital Medical UniversityBeijingChina National Center for Children's Health BeijingChina Beijing Pediatric Reasearch Institute BeijingChina

The viral pneumonia in Wuhan City,China has spread around *** virus has been proven to be a novel coronavirus (named as "2019-nCoV") by World Health Organization (WHO).2019-nCoV belongs to beta-coronavirus *** January 30,2020,WHO re-evaluated the potential effects of 2019-nCoV infection in global public health,and declared this epidemic as a "Public Health Emergency of International Concern (PHEIC)".

关键词： China. treatment belongs

Effect of electrostatic field on seed germination and seedling growth of Sorbus pohuashanesis

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Journal of Forestry Research 2011年第1期22卷 27-34页

作者： YANG ling shen Hai-long School of Forestry Ministry of Education Key Laboratory of ForestTree Genetic Improvement and Biotechnology Northeast Forestry University Harbin 150040 China.

A study was conducted to determine the effects of electrostatic field （ESF） treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System （DPS）, including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability, emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase （SOD）, soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly （to 42.20%）, promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.

关键词： Sorbus pohuashanesis seed germination seedling growth electrostatic treatment

MAX2 Affects Multiple Hormones to Promote Photomorphogenesis

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Molecular Plant 2012年第3期5卷 750-762页

作者： Hui shen ling Zhu Qing-Yun Bu Enamul Huq Section of Molecular Cell and Developmental Biology and the Institute for Cellular and Molecular Biology University of Texas at Austin Austin TX 78712 USA

Ubiquitin-26S proteasome system （UPS） has been shown to play central roles in light and hormone-regulated plant growth and development. Previously, we have shown that MAX2, an F-box protein, positively regulates facets of photomorphogenic development in response to light. However, how MAX2 controls these responses is still unknown. Here, we show that MAX2 oppositely regulates GA and ABA biosynthesis to optimize seed germination in response to light. Dose-response curves showed that max2 seeds are hyposensitive to GA and hypersensitive to ABA in seed ger- mination responses. RT-PCR assays demonstrated that the expression of GA biosynthetic genes is down-regulated, while the expression of GA catabolic genes is up-regulated in the rnax2 seeds compared to wild-type. Interestingly, expression of both ABA biosynthetic and catabolic genes is up-regulated in the max2 seeds compared to wild-type. Treatment with an auxin transport inhibitor, NPA, showed that increased auxin transport in max2 seedlings contributes to the long hypocotyl phenotype under light. Moreover, light-signaling phenotypes are restricted to max2, as the biosynthetic mutants in the strigolactone pathway, max1, max3, and rnax4, did not display any defects in seed germination and seedling de-etiolation compared to wild-type. Taken together, these data suggest that MAX2 modulates multiple hormone pathways to affect photomorphogenesis.

关键词： Arabidopsis F-box protein photomorphogenesis protein degradation strigolactone SCF complex

A Convenient Synthesis of cis and trans-(±)-4-Amino-1-[2-(hydroxyl-methyl)-1,3-oxathiolan-5-yl]-2(1H)-pyrimidinone

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Chinese Chemical Letters 2006年第4期17卷 431-433页

作者： Yi shen ling XIANG Yong DENG Yu Guo ZHONG Department of Medicinal Chemistry West China School of Pharmacy Sichuan University Chengdu 610041

A convenient synthesis of cis-（±） isomer 1 and trans-（±） isomer 2 of lamivudine starting from benzoyloxyacetaldehyde and 1,4-dithiane-2,5-diol is described. The key steps include chlorination of oxathiolane lactol 5 by SOCl2/DMF, followed by coupling with silylated N^4- acetylcytosine and deprotection. The overall yield was 42.6 % and 20,1%, respectively.

关键词： Lamivudine geometrical isomer cis-(±) isomer trans-(±) isomer synthesis.

Photo-Doped Active Electrically Controlled Terahertz Modulator

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Journal of Electronic Science and Technology 2015年第2期13卷 113-116页

作者： Bo Zhang Liang Zhong Ting He Jing-ling shen Department of Physics Capital Normal University

We demonstrate an electric-controlled terahertz（THz） modulator which can be used to realize amplitude modulation of terahertz waves with slight photo-doping. The THz pulse transmission was efficiently modulated by electrically controlling the monolayer silicon-based device. The modulation depth reached 100% almost when the applied voltage was 7V at an external laser intensity of 0.6W/cm2. The saturation voltage reduced with the increase of the photo-excited intensity. In a THz continuous wave（CW）system, a significant fall in both THz transmission and reflection was also observed with the increase of applied voltage. This reduction in the THz transmission and reflection was induced by the absorption for electron injection. The results show that a high-efficiency and high modulation depth broadband electric-controlled terahertz modulator in a pure Si structure has been realized.

关键词： modulator terahertz saturation electrically doping modulated Controlled excited monolayer tunable

Non-coding RNA and neuroinflammation:implications for the therapy of stroke

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Stroke & Vascular Neurology 2019年第2期4卷 96-98页

作者： ling shen Ying Bai Bing Han Honghong Yao Department of Pharmacology School of MedicineSoutheast UniversityNanjingChina

Stroke is the major leading cause of death and serious, long-term disability with major economic consequences. At present, the lack of rapid diagnostic, prognostic biomarkers and effective treatment methods are two major challenges facing stroke. Circular RNAs (circRNAs) are potential clinical biomarkers in central nervous system diseases. However, the potential role of circRNAs in neuroinflammation and neuron functional recovery in acute ischaemic stroke (AIS) remains largely unknown. This review aimed to give an overview of the function of circRNAs in AIS and summarise the latest achievements in this field.

关键词： inflammation acute clinical