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Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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science China(Life sciences) 2006年第2期49卷 115-122页

作者： zhao Hongxin1,2.3, XIE Baoen2.& CHEN Sanfeng1,2.1. State Key Laboratory for Agrobiotechnology and Biological School, China agricultural {2., beijing 100094, China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, China agricultural {2., beijing 100094, China 3. Chemical and Biological School, Shenyang Normal {2., Shenyang 110034, China 1. State Key Laboratory for Agrobiotechnology and Biological School China Agricultural University Beijing 100094 China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing 100094 China 3. Chemical and Biological School ShenYang Normal University Shenyang 110034 China

A 32. bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 102.4 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4 [+]; O2.showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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science China(Life sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, ZHANG HuaiQiang2. SHEN JianZhong3 & gao PeiJi2.1 Institute of Animal science and Veterinary Medicine, Shandong Academy of {2. science, Jinan 2.0100, China 2.State Key Laboratory of Microbial Technology, Shandong university, Jinan 2.0100, China 3 college of Veterinary Medicine, China {2. university, beijing 100094, China 1. Institute of Animal science and Veterinary Medicine Shandong Academy of Agricultural Science Jinan 250100 China 3. college of Veterinary Medicine China Agricultural University Beijing 100094 China 2. State Key Laboratory of Microbial Technology Shandong University Jinan 250100 China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC2.9 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2.nN 0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC2.9 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase; declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity; research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

A SINGLE-PERIOD INVENTORY SYSTEM WITH A GENERAL S-SHAPED UTILITY AND EXPONENTIAL DEMAND

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Journal of Systems science and Systems Engineering 2010年第2期19卷 227-236页

作者： Wei GENG1 Xiaobo zhao2.Deng gao3 Department of Industrial Engineering,Tsinghua {2.,{2. 100084,China Department of Industrial Engineering Tsinghua University Beijing China

We discuss a single-period inventory system with a general S-shaped utility function and exponential demand. It is shown that there exists a state-dependent order-up-to policy to be optimal. Behaviors of optimal polic... 详细信息

关键词： Inventory S-shaped utility function order-up-to policy

Ultraconformable Integrated Wireless Charging Micro-Supercapacitor Skin

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Nano-Micro Letters 2024年第7期16卷 46-58页

作者： Chang gao Qing You Jiancheng Huang Jingye Sun xuan Yao Mingqiang Zhu {2. zhao Tao Deng School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China School of Microelectronics Tianjin UniversityTianjin 300072People’s Republic of China Key Laboratory of Cluster science Ministry of Education of China Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China

Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft ***,current wire-less charging power sources are still restricted by limited flexural angles and fragile connection of components,resulting in the failure expression of performance and constraining their fur-ther applications in health monitoring wearables and moveable artificial ***,we present an ultracompatible skin-like integrated wireless charging micro-supercapacitor,which building blocks(including electrolyte,electrode and substrate)are all evaporated by liquid *** to the infiltration and permeation of the liquid,each part of the integrated device attached firmly with each other,forming a compact and all-in-one *** addition,benefitting from the controllable volume of electrode solution precursor,the electrode thickness is easily regulated varying from 11.7 to 112.5μ*** prepared thin IWC-MSC skin can fit well with curving human body,and could be wireless charged to store electricity into high capacitive micro-supercapacitors(11.39 F cm-3)of the integrated *** believe this work will shed light on the construction of skin-attachable electronics and irregular sensing microrobots.

关键词： Micro-supercapacitor Electronic skin Supercapacitor skin Wireless charging energy storage device

Expressed sequence tag analysis and cloning of trehalose-6-phosphate synthase gene from marine alga Laminaria japonica(Phaeophyta)

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Acta Oceanologica Sinica 2012年第6期31卷 139-148页

作者： xuAN Jinsong 1,4,FENG Yanbin 1,WENG Manli 1,zhao Ge 1,SHI Jinfeng 1,YAO Jianting 2.WANG Xiuliang 2.GUO Baotai 3,QIAO Lixian 3,DUAN Delin 2.WANG Bin 1 1 The State Key Laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,Chinese Academy of {2.s,{2. 100101,China 2.The State Key Laboratory of Marine Biology,Institute of Oceanology,Chinese Academy of {2.s,Qingdao 2.6071,China 3 college of Life {2.s,Qingdao agricultural university,Qingdao 2.6109,China 4 Department of Biological {2. and Engineering,School of Chemical and Biological Engineering,university of {2. and Technology {2.,beijing 100083,China 1. The State Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China 4. Department of Biological science and Engineering School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China 2. The State Key Laboratory of Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 3. college of Life sciences Qingdao Agricultural University Qingdao 266109 China

A high quality cDNA library was constructed from the brown alga Laminaria japonica,with the titer of 1.2.10 5 pfu/*** average insert size of the cDNA library is about 1.6 *** the cDNA library,591 cDNA clones were randomly selected and *** a result,574 EST(expressed sequence tag) sequences were *** of the 574 ESTs were submitted to the dbEST database section of GenBank with the accession numbers from CX942.2. to *** cDNA library was screened with a α-32.p labeled 453 bp T P S gene probe,which is a partial sequence yielded from Porphyra *** positive cDNA clones were screened and the sequencing data showed that these four cDNA clones covered majority of *** TPS cDNA *** PCR amplification,sequencing and assembling,the entire ORF(open reading frame) sequence of the T P S gene was obtained,which was named *** encodes a protein containing 908 amino acids with a calculated molecular mass of 101 674 *** LjTPS gene was successfully expressed in *** and *** LjTPS gene has potential application both in plant breeding to stress tolerance and in deciphering the T P S gene function and mechanism to stress tolerance.

关键词： cDNA library comparative study expressed sequence tag(EST) analysis Laminaria japonica trehalose-6-phosphate synthase(TPS) T P S gene

The MADS-box gene RhAGL6 plays a master role in regulating the receptacle malformation in rose at low temperature

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Horticultural Plant Journal 2024年第5期10卷 1214-1229页

作者： Weikun Jing Shuai Zhang Qingcui zhao yang Liu Liangjun zhao Junping gao Nan Ma Xiaofeng Zhou Yonghong Li School of Food and Drug Shenzhen PolytechnicShenzhen 518055China Department of Ornamental Horticulture College of HorticultureChina Agricultural UniversityBeijing 100193China Postdoctoral Innovation Practice Base Shenzhen PolytechnicShenzhen 518055China Flower Research Institute of Yunnan Academy of agricultural sciences KunmingYunnan 650205China

Low temperature usually results in the developmental deformity of flower organs,immensely affecting the quality of rose ***,it's largely unknown about the regulatory mechanisms activated by low ***,we used a low temperature-sensitive Rosa hybrida cv.‘Peach Avalanche’to screen a MADS-box gene RhAGL6 via conjoint analysis between RNA sequencing(RNA-seq)and whole-genome bisulfite sequencing(WGBS).Furthermore,we found that low temperature induced the hypermethylation and elevated histone 3 lys-2. trimethylation(H3K2.me3)level on the RhAGL6 promoter,leading to decreased RhAGL6 *** addition,RhAGL6 silencing resulted in the formation of abnormal *** also found that the levels of gibberellins(GA3)and abscisic acid(ABA)in the receptacle under low temperature were lower and higher,respectively,than under normal *** activity analysis revealed that GA3 significantly activated RhAGL6 promoter activity,whereas ABA inhibited ***,we propose that RhAGL6 regulates rose receptacle development by integrating epigenetic regulation and phytohormones signaling at low temperature.

关键词： Rosa hybrida Low temperature RhAGL6 Receptacle development DNA methylation H3K2.me3 Phytohormone

Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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science China Earth sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3, zhao Jun2. zhao Shiwei2.& {2. Yonghui2.1. The Key Laboratory of Modern Precision Agriculture System Integration Research, college of Hydraulic and Civil Engineer-ing, China agricultural university, beijing 100083, China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, {2.ling 712.00, China 3. Geographic and Resources Management college, Yantai Normal university, Yantai 2.402., China 1. The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling 712100 China 3. Geographic and Resources Management college Yantai Normal University Yantai 264025 China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.39% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

Human radiological safety assessment for petawatt laser-driven ion acceleration experiments in CLAPA-T

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Matter and Radiation at Extremes 2024年第4期9卷 8-15页

作者： Xiaopeng Zhang Jiarui zhao Shengxuan xu xun Chen Ying gao Shiyou Chen Kun Zhu xueqing Yan Wenjun Ma State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsCASBeijing 100049China beijing Laser Acceleration Innovation Center HuairouBeijing 101400China Institute of Guangdong Laser Plasma Technology BaiyunGuangzhou 510540China

The newly built Compact Laser Plasma Accelerator-Therapy facility at Peking university will deliver 60 J/1 Hz laser pulses with 30 fs *** by this petawatt laser facility,proton beams with energy up to 2.0 MeV are expected to be generated for tumor *** high-repetition operation,both prompt radiation and residual radiation may cause safety ***,human radiological safety assessment before commissioning is *** this paper,we simulate both prompt and residual radiation using the Geant4 and FLUKA Monte Carlo codes with reasonable proton and as-produced electron beam *** find that the prompt radiation can be shielded well by the concrete wall of the experimental hall,but the risk from residual radiation is nonnegligible and necessitates adequate radiation *** the basis of the simulation results,we discuss the constraints imposed by radiation safety considerations on the annual working time,and we propose radiation cooling strategies for different shooting modes.

关键词： laser prompt acceleration

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： Xin FENG Liaoliang KE yang gao college of science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect