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Gene Expression of Ornithine Decarboxylase in Lung Cancers and Its Clinical Significance

Acta Biochimica et Biophysica Sinica 2006年第9期38卷 639-645页

作者： Hui TIAN~1* Qing HUANG~1 Lm li~1 Xian-Xi liU~2 Yan ZHANG~2 1 department of Thoracic Surgery,Shandong university Qi Lu Hospital,Jinan 250012,china 2 department of Medicine,Medical Molecular Biology Experimental Center,Shandong university,Jinan 250012,china department of Thoracic Surgery Shandong University Qi Lu HospitalJinan 250012 China department of Medicine Medical Molecular Biology Experimental Center Shandong UniversityJinan 250012 China

Lung cancer is one of the most lethal cancers in china because of its high incidence and *** decarboxylase （ODC）,an important enzyme in polyamine biosynthesis,is increased incancer *** chemotherapeutic agents aimed at reducing ODC expression show inhibitory effects oncancer cell growth,so ODC can be useful in gene diagnosis and gene therapy of *** this study,weexamined the effect of antisense ODC on lung cancer cells.A-549 cells were infected with rAd-ODC/Ex3as,a recombinant adenovirus containing the cytomegalovirus promoter,green fluorescent protein gene and 120bp antisense *** cell cycle was evaluated by flow cytometry.A nude mouse xenograft model wasused in the tumorigenicity *** transcription-polymerase chain reaction,Western blot and immuno-histochernistry were used to study the expressions of ODC on lung *** was found that the growth ofcells infected with rAd-ODC/Ex3as was substantially inhibited and cells were arrested at *** with rAd-ODC/Ex3as can suppress tumor formation in a nude mouse xenograft *** of ODC mRNA and ODC protein levels in lung cancer tissues was significantly higher than thatin normal tissues （P<0.05）,which correlated significantly with the stage of lung cancer （P<0.05）.This studysuggested that rAd-ODC/Ex3as has antitumor activity in human lung cancer *** ODC gene might playan important role in lung cancer and the overexpression of ODC might be related to the occurrence anddevelopment of lung cancer.

关键词： polyamine biosynthesis lung neoplasm ornithine decarboxylase A-549 cell line

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Target tracking in wireless sensor networks using adaptive measurement quantization

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Science china(Information Sciences) 2012年第4期55卷 827-838页

作者： ZHOU Yan 1,2,li JianXun 2 & WANG Dongli 1 1 Colleage of Information Engineering,Xiangtan university,Xiangtan 411105,china 2 department of Automation,Shanghai Jiao Tong university,Shanghai 200240,china Colleage of Information Engineering Xiangtan University Xiangtan China department of Automation Shanghai Jiao Tong University Shanghai China

Quantization/compression is usually adopted in wireless sensor networks (WSNs) since each sensor node typically has very limited power supply and communication *** consider the problem of target tracking in a WSN with quantized measurements in this *** is focused on the design of measurement quantizer with adaptive *** on the probability density function (PDF) of the signal amplitude measured at a random location and by maximizing the entropy,an adaptive design method for quantization thresholds is *** to the nonlinear measuring and quantization models,particle filtering (PF) is adopted in the fusion center (FC) to estimate the target *** Cram'er-Rao lower bounds (CRLBs) for tracking accuracy using quantized measurements are also ***,a simulation example on tracking single target with noisy circular trajectories is provided to illustrate the effectiveness of the proposed approach.

关键词： target tracking wireless sensor network adaptive quantization posterior Cram’er-Rao lower bound

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Recurrence spectra of He atoms in strong external fields

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： liN Shenglu1, li Hongyun1, WANG Dehua2, ZHAO Wenli1 & GAO Feng1 1. department of Physics, Shandong Normal university, Jinan 250014, china 2. department of mathematics and Physics, Shandong Institute of Architecture and Engineering, Jinan 250014, china department of Physics Shandong Normal University Jinan China department of mathematics and Physics Shandong Institute of Architecture and Engineering Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

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Combined perturbation bounds:Ⅱ.Polar decompositions

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Science china mathematics 2007年第9期50卷 1339-1346页

作者： Wen li~(1+) Wei-wei SUN~2 1 School of Mathematical Sciences,South china Normal university,Guangzhou 510631,china 2 department of mathematics,City university of Hong Kong,Hong Kong,china School of Mathematical Sciences South China Normal University Guangzhou China department of mathematics City University of Hong Kong Hong Kong China

In this paper,we study the perturbation bounds for the polar decomposition A=QH where Q is unitary and H is *** optimal (asymptotic) bounds obtained in previous works for the unitary factor,the Hermitian factor and singular values of A areσ_r^2||ΔQ||_F^2≤||ΔA||_F^2, 1/2||ΔH||_F^2≤||ΔA||_F^2 and ||Δ∑||_F^2≤||ΔA||_F^2,respectively,where∑=diag(σ_1,σ_2,...,σ_r,0,...,0) is the singular value matrix of A andσ_r denotes the smallest nonzero singular *** we present some new combined (asymptotic) perturbation boundsσ_r^2||ΔQ||_F^2+1/2||ΔH||_F^2≤||ΔA||_F^2 andσ_r^2||ΔQ||_F^2+||Δ∑||_F^2≤||ΔA||_F^2 which are optimal for each *** corresponding absolute perturbation bounds are also given.

关键词： polar decomposition perturbation singular value

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Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： yang Geng Zian Jia ling li 635 Prices Fork Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also often embody dynamic characteristics such as environmental responsiveness,autonomy,and self-healing,which are difficult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus facilitating the construction of functional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical performance while maintaining important“living”*** we summarize the recent progress and provide our perspectives for this emerging research *** first summarize the superiority of structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the definition and classifications of structural ELMs,their mechanical performance,and physiological ***,we summarize some critical challenges faced by structural ELMs and highlight directions of future *** hope this review article can provide a timely summary of the state of the art and relevant perspectives for future development of structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

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Untethered Micro/Nanorobots for Remote Sensing:Toward Intelligent Platform

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Nano-Micro Letters 2024年第2期16卷 450-483页

作者： Qianqian Wang Shihao yang li Zhang Jiangsu Key Laboratory for Design and Manufacture of Micro‑Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing 211189People’s Republic of China department of Mechanical and Automation Engineering The Chinese University of Hong KongShatinHong Kong 999077People’s Republic of China Chow Yuk Ho Technology Centre for Innovative Medicine The Chinese University of Hong KongShatinHong Kong 999077People’s Republic of China T Stone Robotics Institute The Chinese University of Hong KongShatinHong Kong 999077People’s Republic of China department of Surgery The Chinese University of Hong KongShatinHong Kong 999077People’s Republic of China

Untethered micro/nanorobots that can wirelessly control their motion and deformation state have gained enormous interest in remote sensing applications due to their unique motion characteristics in various media and diverse *** are developing micro/nanorobots as innovative tools to improve sensing performance and miniaturize sensing systems,enabling in situ detection of substances that traditional sensing methods struggle to *** the past decade of development,significant research progress has been made in designing sensing strategies based on micro/nanorobots,employing various coordinated control and sensing *** review summarizes the latest developments on micro/nanorobots for remote sensing applications by utilizing the self-generated signals of the robots,robot behavior,microrobotic manipulation,and robot-environment *** recent studies and relevant applications in remote sensing,we also discuss the challenges and future perspectives facing micro/nanorobots-based intelligent sensing platforms to achieve sensing in complex environments,translating lab research achievements into widespread real applications.

关键词： Micro/nanorobot Remote sensing Wireless control Self-propulsion Actuation at small scales

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A preliminary study on vegetation-erosion dynamics and its applications

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Science china Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2 , WANG Guangqian 1 , li Changzhi 1 & WANG Feixin 1 1. department of Hydraulic Engineering, Tsinghua university, Beijing 100084, china 2. International Research and Training Center on Erosion and Sedimentation, Beijing 100084, china department of Hydraulic Engineering Tsinghua University Beijing China International Research and Training Center on Erosion and Sedimentation Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

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Disequilibria between ^(210)Po and ^(210)Pb in surface waters of the southern South china Sea and their implications

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Science china Earth Sciences 2006年第1期49卷 103-112页

作者： yang Weifeng, HUANG Yipu1,2, CHEN Min1,2, ZHANG Lei, li Hongbin, liU Guangshan1,2 & QIU Yusheng1,2 1. department of Oceanography, Xiamen university, Xiamen 361005, china 2. State Key Laboratory of Marine Environmental Science, Xiamen university, Xiamen 361005, china department of Oceanography Xiamen University Xiamen China State Key Laboratory of Marine Environmental Science Xiamen University Xiamen China

Activities of the naturally occurring radionuclides, ^(210)Pb and ^(210)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South china Sea. The average activity of particulate ^(210)Pb, 0.23 Bq/m^3 (n= 23), accounted for about 12% of the total ^(210)Pb, which corresponds with values of open *** ^(210)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(210)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(210)Po and ^(210)Pb in surface waters estimated from an irreversible steady-state model were0.82 a and 1.16 a, respectively. The consistently high fractionation factor calculated either byscavenging rate constants (5.42) or K_d values (6.69) suggested that a significant fractionationoccurred between ^(210)Po and ^(210)Pb during their removal from solution to particles and that thetwo radionuclides had different biogeochemical cycling pathways in the oligotrophic South china ***, our results indicated that there exist different fractionation mechanisms between^(210)Po and ^(210)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(210)Po and ^(210)Pb, by which ^(210)Po and ^(210)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(210)Po and fractionate ^(210)Po and ^(210)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(210)Po to trace marine biogeochemicalprocesses relating to microbial activities and the cycling of sulfur group elements (S, Se, Te andPo).

关键词： South china Sea, 210Po, 210Pb, disequilibria, scavenging.

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A new approximating method for Holstein model

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 44-48页

作者： REN XueZao 1 , liAO Xu 1 , li Lei 1 & WANG Kelin 2 1 School of Science, Southwest university of Science and Technology, Mian yang 621010, china 2 department of Modern Physics, university of Science and Technology of china, Hefei 230026, china School of Science Southwest University of Science and Technology Mian Yang China department of Modern Physics University of Science and Technology of China Hefei China

A new approach-the method of coherent state orthogonal expansion is developed for one-dimensional Holstein model. In zeroth order approximation, the formula of ground state energy is deduced analytically and the solutions in strong- and weak-coupling limits are obtained correctly. When the trial wave-function of ground state is expanded to the second order, the obtained ground state energy agrees quite well with that calculated by numerical method in all coupling regimes. The present approach can be easily generalized to the situations of higher dimensions and more electrons.

关键词： coherent-state orthogonal expansion polaron simulated annealing method

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BAF Complex Is Closely Related to and Interacts with NF1/CTF and RNA Polymerase Ⅱ in Gene Transcriptional Activation

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Acta Biochimica et Biophysica Sinica 2005年第7期37卷 440-446页

作者： li-Hui ZHAO~(1,2) Xue-Qing BA~1 Xiao-Guang WANG~3 Xiao-Juan ZHU~1 li WANG~1 Xian-Lu ZENG~1 1 Institute of Genetics and Cytology,Northeast Normal university,Changchun 130024,china 2 College of Agronomy,Jilin Agricultural university,Changchun 130118,china 3 department of Biology,Changchun Normal College,Changchun 130032,china Institute of Genetics and Cytology Northeast Normal UniversityChangchun 130024 China College of Agronomy Jilin Agricultural UniversityChangchun 130118 China department of Biology Changchun Normal CollegeChangchun 130032 China

Brg-or hBrm-associated factor (BAF) complexes,a chromatin-remodeling complex family ofmammalian cells,facilitate transcriptional activity by remodeling nucleosome ***1 is the coresubunit of Brg-associated factor *** the present study,we investigated the spatial relationshipbetween Brg1 and nuclear factor 1 (NF1/CTF) and RNA polymerase Ⅱ (RNAP Ⅱ) upon gene transcriptionalactivation in vivo by employing immuno-gold *** data showed that Brg1 was closely co-localizedwith NF1/CTF and RNAP Ⅱ in HeLa ***,the co-immunoprecipitation assay further revealedthat Brg1 can be isolated together with NF1/CTF and RNAP Ⅱ in the ConA-stimulated,but not the resting,T *** combined results suggested that BAF complexes can interact with NF1/CTF and RNAPⅡ,and this interaction is closely dependent on the activation of gene transcription.

关键词： BAF complex NF1/CTF RNAP Ⅱ gene transcription

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