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Analysis of the 3' ends of tRNA as the cause of insertion sites of foreign DNA in Prochlorococcus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 708-718页

作者： hai-lan LIU Jun zhu Institute of Bioinformaties College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Institute of Maize Research College of Agriculture Sichuan Agricultural University Ya'an 625014 China

The purpose of this study was to investigate the characteristics of transfer RNA(tRNA) responsible for the association between tRNA genes and genes of apparently foreign origin(genomic islands) in five high-light adapted Prochlorococcus *** bidirectional best BLASTP(basic local alignment search tool for proteins) search and the conservation of gene order against each other were utilized to identify genomic islands,and 7 genomic islands were found to be immediately adjacent to tRNAs in Prochlorococcus marinus AS9601,11 in *** MIT9515,8 in *** MED4,6 in *** MIT9301,and 6 in *** *** Carlo simulation showed that tRNA genes are hotspots for the integration of genomic islands in Prochlorococcus *** tRNA genes associated with genomic islands showed the following characteristics:(1) the association was biased towards a specific subset of all iso-accepting tRNA genes;(2) the codon usages of genes within genomic islands appear to be unrelated to the codons recognized by associated tRNAs;and,(3) the majority of the 3' ends of associated tRNAs lack CCA *** findings contradict previous hypotheses concerning the molecular basis for the frequent use of tRNA as the insertion site for foreign genetic *** analysis of a genomic island associated with a tRNA-Asn gene in *** MIT9301 suggests that foreign genetic material is inserted into the host genomes by means of site-specific recombination,with the 3' end of the tRNA as the target,and during the process,a direct repeat of the 3' end sequence of a boundary tRNA(namely,a scar from the process of insertion) is formed elsewhere in the genomic *** the analysis of the sequences of these targets,it can be concluded that a region characterized by both high GC content and a palindromic structure is the preferred insertion site.

关键词： Genomic islands Prochlorococcus Transfer RNA(tRNA) Palindromic structure Codon usage

A Case for Adaptive Resource Management in Alibaba Datacenter Using Neural Networks

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Journal of Computer Science & Technology 2020年第1期35卷 209-220页

作者： Sa Wang Yan-hai zhu Shan-Pei Chen Tian-Ze Wu Wen-Jie Li Xu-Sheng Zhan hai-Yang Ding Wei-Song Shi yun-Gang Bao State Key Laboratory of Computer Architecture Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Peng Cheng Laboratory Shenzhen 518055China Alibaba Inc. Hangzhou 311121China Department of Computer Science Wayne State UniversityMichiganMI 48202U.S.A

Both resource efficiency and application QoS have been big concerns of datacenter operators for a long time,but remain to be *** resource utilization increases the risk of resource contention between co-located workload,which makes latency-critical(LC)applications suffer unpredictable,and even unacceptable *** of prior work devotes the effort on exploiting effective mechanisms to protect the QoS of LC applications while improving resource *** this paper,we propose MAGI,a resource management runtime that leverages neural networks to monitor and further pinpoint the root cause of performance interference,and adjusts resource shares of corresponding applications to ensure the QoS of LC *** is a practice in Alibaba datacenter to provide on-demand resource adjustment for applications using neural *** experimental results show that MAGI could reduce up to 87.3%performance degradation of LC application when co-located with other antagonist applications.

关键词： resource management neural network resource efficiency tail latency

An iterative approach to Bayes risk decoding and system combination

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第3期12卷 204-212页

作者： hai-hua XU Jie zhu Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

We describe a novel approach to Bayes risk(BR) decoding for speech recognition,in which we attempt to find the hypothesis that minimizes an estimate of the BR with regard to the minimum word error(MWE) *** achieve this,we propose improved forward and backward algorithms on the lattices and the whole procedure is optimized *** remarkable characteristics of the proposed approach are that the optimization procedure is expectation-maximization(EM) like and the formation of the updated result is similar to that obtained with the confusion network(CN) decoding *** results indicated that the proposed method leads to an error reduction for both lattice rescoring and lattice-based system combinations,compared with CN decoding,confusion network combination(CNC),and ROVER methods.

关键词： Bayes risk(BR) Confusion network Speech recognition Lattice rescoring System combination

Numerical investigation of the influence of companion drops on drop-on-demand ink jetting

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第8期13卷 584-595页

作者： hai-yun ZHANG Jin WANG Guo-dong LU Institution of Engineering and Computer Graphics Zhejiang UniversityHangzhou 310027China

In this study we characterized and investigated the specific phenomenon of "companion drops" in the drop-ondemand(DOD) ink jetting process.A series of simulations based on a piezoelectric DOD printhead system is presented,adapting the volume-of-fluid(VOF) interface-capturing method to track the boundary evolution and model the interfacial *** results illustrate the causality between the generation of companion drops and droplet deviation behavior,as well as their close correlations with ink jetting straightness and printing *** characteristics of companion drops are summarized and compared with those of satellite ***,a theoretical mechanism for the generation of companion drops is presented,and their effects and behaviors are analyzed and ***,the effects of critical factors on the generation of companion drops are investigated and characterized based on variations in the printable pressure *** are given for the suppression of companion drops and for the improvement of printing accuracy.

关键词： Drop-on-demand (DOD) ink jetting Droplet deviation Companion drops Computational fluid dynamics (CFD) Volume-of-fluid (VOF) method

Herbicidal activity of Aureobasidium pullulans PA-2 on weeds and optimization of its solid-state fermentation conditions

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Journal of Integrative Agriculture 2020年第1期19卷 173-182页

作者： GUO Qing-yun CHENG Liang zhu hai-xia LI Wei WEI You-hai CHEN Hong-yu GUO Liang-zhi WENG Hua WANG Jian Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810016P.R.China Key Laboratory of Agricultural Integrated Pest Management in Qinghai Province Xining 810016P.R.China Scientific Observing and Experimental Station of Crop Pests in Xining Ministry of Agriculture and Rural AffairsXining 810016P.R.China State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016P.R.China

Fungal strain PA-2 was isolated from infected poplar leaves from the Ping’an District, haidong City of Qinghai Province, China. Based on the culture characteristics and the internal transcribed spacer(ITS) sequence of its 16S r DNA, the strain was identified as Aureobasidium pullulans. The culture and metabolites of strain PA-2 showed high herbicidal potential to five tested weeds Galium aparine var. tenerum, Chenopodium album, Malva crispa, Polygonum lapathifolium and Avena fatua. For the in vitro test, 5 days after the detached leaves were inoculated with PA-2 culture, all leaves infected by the hyphae and became black and rotten. For the in vivo test, a metabolite filtrate of PA-2 culture was sprayed over the living weed plants, and five days after inoculation, the weed plants became withered and necrotic. Seven days after inoculation, the fresh weight reductions of G. aparine var. tenerum, C. album, M. crispa, P. lapathifolium and A. fatua were 87.25, 78.46, 82.25, 62.11, and 80.27%, respectively. Galium aparine var. tenerum and M. crispa exhibited significant reductions in fresh weight. The bio-safety test on the five crops showed no significant plant height reductions, which was also observed for wheat(Triticum aestivum), faba bean(Vicia faba), and barley(Hordeum vulgare). By contrast, oilseed rape(Brassica napus) and pea(Pisum sativum) exhibited light spots but no significant reductions in plant height. These results indicated that A. pullulans could be a potential microbial herbicide for the control of the target weeds in crops. Optimization of the carbon and nitrogen sources for cultural media and substances for solid-state fermentation indicated that PA-2 had better colony growth and spore production with the optimal carbon source of glucose(C4), nitrogen source of soybean flour(N2), and the optimal substance was wheat bran. The results in this study provide useful information for the development ofA. pulluans PA-2 as an herbicide for bio-control of the we

关键词： A.pullulans weeds biological control crop safety optimum media condition

Relation between microstructure and magnetic properties of shock wave-compressed Nd-Fe-B magnets

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Rare Metals 2022年第7期41卷 2353-2356页

作者： Ming-Gang zhu Yan-Feng Li Wei Li Li-yun Zheng Dong Zhou hai-Bo Feng Lang Chen An Du Division of Functional Materials Central Iron and Steel Research InstituteBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China College of Science Northeastern UniversityShenyang 110819China

The relationship between the microstructure and magnetic properties of Nd-Fe-B sintered magnet compressed by shock wave with 6.26 GPa≤p≤7.16 GPa was *** reveals that Nd-Fe-B magnets show a demagnetization behavior after compressed by shock *** intergranular fracture is the main occurring phe-nomenon in the shock wave-compressed *** coercivity of the shock wave-compressed Nd-Fe-B magnets could be recovered after repeating the annealing *** suggests that only the morphology change just like the intergranular fracture occurs,and there is no structural change in the grain boundary phase in the shock wave-compressed *** phase grain interconnection,microcracks and pores,and alterant orientation relationship between matrix phase and grain boundaries phase are con-sidered as induced factors of demagnetization.

关键词： Permanent magnets Coercivity Shock wave Demagnetization

The Normalizer Property for Integral Group Rings of Holomorphs of Finite Groups with Trivial Center

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Acta Mathematica Sinica,English Series 2020年第4期36卷 401-406页

作者： Jin Ke hai Yi Xin zhu College of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

Let G=Hol(H)be the holomorph of a finite group *** there is a prime q dividing|H|such that every q-central automorphism of H is inner and Z(H)=1,then every Coleman automorphism of G is *** particular,the normalizer pr... 详细信息

关键词： Coleman automorphisms characteristically simple group normalizer property

Experimental investigation and correlations for proppant distribution in narrow fractures of deep shale gas reservoirs

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Petroleum Science 2022年第2期19卷 619-628页

作者： Hao Zeng Yan Jin hai Qu yun-Hu Lu College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China College of Petroleum Engineering Chongqing University of Science and TechnologyChongqing401331China

Hydraulic fracturing is a crucial stimulation for the development of deep shale gas reservoirs.A key challenge to the effectiveness of hydraulic fracturing is to place small proppants in complex narrow fractures *** experiments with varied particle and fluid parameters are carried out in a narrow planar channel to understand particle transport and *** four dimensionless parameters,including the Reynold number,Shields number,density ratio,and particle volume fraction,are introduced to describe the particle transport in narrow *** results indicate that the narrow channel probably induces fluid fingers and small particle aggregation in a highly viscous fluid,leading to particle settlement near the *** low viscous fluid is beneficial to disperse particles further into the fracture,especially in the high-speed fluid *** linear and natural logarithmic laws have relationships with dimensionless parameters *** multiple linear regression method developed two correlation models with four dimensionless parameters to predict the bed equilibrium height and covered area of small particles in narrow *** study provides fundamental insight into understanding small size proppant distribution in deep reservoirs.

关键词： Proppant transport Multiphase flow Hydraulic fracturing Deep reservoir Narrow fractures

Mild and highly regioselective synthesis of biaryl acids via Rh （I）-catalyzed cross-dehydrogenative coupling of benzoic acids using sodium chlorite as oxidant

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 3-8页

作者： yun Liu Youquan zhu Chaojun Li Department of Chemistry FQRNT Center for Green Chemistry and Catalysis McGill University Montreal Quebec H3AOB8 Canada Department of Chemistry and Chemical Engineering Jiangsu Normal University Xuzhou 221116 China

A mild and efficient synthesis for the biaryl acids via rhodium-catalyzed cross-dehydrogenative coupling reaction has been developed. This novel protocol with sodium chlorite as an oxidant featured many advantages such as mild reaction conditions, high regioselectivity, tolerance of various functional groups, and good to excellent yields.

关键词： biaryl acids cross-dehydrogenative coupling rhodium-catalyzed