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

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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 DeportmentofThoracicSurgery ShandongUniversityQiLuHospitalJinon250012China DepartmentofMedicine MedicalMolecularBiologyExperimentalCenterShandongUniversityJinan250012China

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 （Pyan 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

Glacial-interglacial cycles recorded in clay minerals from the eastern Tibetan Plateau over the last 800 ka and their indications

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Science China Earth Sciences 2024年第7期67卷 2162-2177页

作者： Xiaoyan zhang Chunxia zhang yan ZHAO Bin HU Zhengtang GUO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Clay mineral proxies have been widely used to reconstruct changes in provenance and the ***,high-altitude clay mineral indications and long-term and orbital variations have not been fully ***,we present an800-ka clay-mineral record from a lacustrine sediment core(ZB13-C2)from the Zoige Basin on the eastern Tibetan Plateau(TP).X-ray diffraction and scanning electron microscopy were used to identify the clay mineral assemblages and their micromorphological characteristics of core *** results revealed that the clay minerals in core ZB13-C2 are mainly illite,with small amounts of chlorite,kaolinite,and smectite(including irregular mixed-layers of illite-smectite(I/S)and chloritesmectite(C/S)).The clay mineral assemblages and proxies exhibit three stages of change,which are mainly controlled by the Zoige watershed range under different climate *** watershed was limited to the southeastern region with altitudes ranging from~3500 to~4200 meters above sea level(m a.s.l.),and glacial-interglacial hydraulic erosion controlled the input of bedrock debris during 800-621 ka *** expanded to higher altitudes(~4200 to~4700 m a.s.l.)due to stronger seasonal freezethaw weathering without significant glacial-interglacial variations under a cooling and drying climate during 621-100 ka ***,it expanded to its highest altitudes of~4700 to~5200 m *** of the watershed after 100 ka BP,and hydraulic erosion increased obviously under a warm climate of the interstadial MIS 3 on the *** watershed underwent two major expansions under different climatic conditions at~621 ka and 100 ka BP,with the wet/dry alternation became strong at~621 ka *** results reveal that long-term temperature changes and the wet/dry alternation at high altitudes controlled the watershed range and degree of the physical erosion,and that the indications of clay minerals should be carefully clarified before they are used as climate indicators,especi

关键词： Quaternary Zoige Basin Lacustrine sediments Paleoenvironment Weathering

Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 111-136页

作者： Zhiyuan WU Linchuan ZHAO Han yan Ge yan Ao CHEN Wenming zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace Systems Engineering Shanghai 201108China

Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery.

关键词： shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： yan XU He HUANG Chao zhang Rongji FU School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis

E-MobileNeXt: face expression recognition model based on improved MobileNeXt

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Optoelectronics Letters 2024年第2期20卷 122-128页

作者： zhang Xiang yan Chunman School of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070China1

In response to the high complexity and low accuracy of current facial expression recognition networks, this paper proposes an E-Mobile Ne Xt network for facial expression recognition. E-Mobile Ne Xt is built based on our proposed E-Sand Glass block. In addition, we also improve the overall performance of the network through Rep Conv and SGE attention mechanisms. The experimental results show that the network model improves the expression recognition accuracy by 6.5% and 7.15% in RAF-DB and CK+ datasets, respectively, while the parameter and floating-point operations decreased by 0.79 M and 4.2 M compared with Mobile Ne Xt.

关键词： facial mechanisms. network

Kinetic model of vibration screening for granular materials based on biological neural network

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Particuology 2024年第5期88卷 98-106页

作者： Zhan Zhao yan zhang Fang Qin Mingzhi Jin School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Shandong Academy of Agricultural Machinery Sciences Ji'nan250100China

The kinetic model is the theoretical basis for optimizing the structure and operation performance of vibration screening *** this paper,a biological neurodynamic equation and neural connections were established according to the motion and interaction properties of the material under vibration *** material feeding to the screen and the material passing through apertures were considered as excitatory and inhibitory inputs,respectively,and the generated stable neural activity landscape was used to describe the material distribution on the 2D screen *** dynamic process of material vibration screening was simulated using discrete element method(DEM).By comparing the similarity between the material distribution established using biological neural network(BNN)and that obtained using DEM simulation,the optimum coefficients of BNN model under a certain screening parameter were determined,that is,one relationship between the BNN model coefficients and the screening operation parameters was *** screening parameters were randomly selected,and the corresponding relationships were established as a ***,with straw/grain ratio,aperture diameter,inclination angle,vibration strength in normal and tangential directions as inputs,five independent adaptive neuro-fuzzy inference systems(ANFIS)were established to predict the optimum BNN model coefficients,*** training results indicated that ANFIS models had good stability and *** flexibility and adaptability of the proposed BNN method was demonstrated by modeling material distribution under complex feeding conditions such as multiple regions and non-uniform rate.

关键词： Kinetic model Material distribution Vibration screening Biological neural network DEM simulation Adaptive neuro-fuzzy inference systems

Climatic implications in earlywood and latewood width indices of Chinese pine in north central China

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Journal of Forestry Research 2024年第3期35卷 143-153页

作者： Kaixuan yang Junzhou zhang Haowen Fan Yuan yan College of Geographic Sciences Qinghai Normal UniversityXining 810016People's Republic of China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Xining 810016People's Republic of China Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030People's Republic of China Gansu Liancheng Forest Ecosystem Field Observation and Research Station Lanzhou UniversityLanzhou 730333People's Republic of China School of Geography and Information Engineering University of GeoscienceWuhan 430074People's Republic of China

Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern ***,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW *** this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains,north central *** climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation *** analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate ***,after removing the effect of earlywood growth using a simple regression model,the adjusted LWW chronology(LWW_(adj))showed a strong relationship with July precipitation in dry *** suggests that the LWW_(adj) chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions.

关键词： Dendroclimatology Latewood width Climate response Summer precipitation Earlywood effect

Velocity-Incorporated Wear Model of Rolling Guide Shoe Material Selection

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 118-135页

作者： Longye Chen Lingyu yan Chengliang Liu Zhinan zhang School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

To ensure an accurate selection of rolling guide shoe materials,an analysis of the intricate relationship between linear speed and wear is *** element simulations and experimental measurements are employed to evaluate four distinct types of materials:polyurethane,rubber,polytetrafluoroethylene(PTFE),and *** speed-index of each material is measured,serving as a preparation for subsequent ***,the velocity-wear factor is determined,providing insights into the resilience and durability of the material across varying ***,a wear model tailored specifically for viscoelastic bodies is explored,which is pivotal in understanding the wear mechanisms within the *** this model,wear predictions are made under higher speed conditions,facilitating the choice of material for rolling guide *** validate the accuracy of the model,the predicted degree of wear is compared with experimental data,ensuring its alignment with both theoretical principles and real-world *** comprehensive analysis has verified the effectiveness of the model in the selection of materials under high-speed conditions,thereby offering confidence in its reliability and ensuring optimal performance.

关键词： Archard model Wear model Speed-index Wear prediction

Bioinspired designs in active metal-based batteries

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Nano Research 2024年第2期17卷 587-601页

作者： Fan zhang Ting Liao Cheng yan Ziqi Sun School of Chemistry and Physics Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia School of Mechanical Medical and Process Engineering Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia QUT Centre for Materials Science Queensland University of TechnologyGeorge StreetBrisbaneQLD 4000Australia

Active metal-based batteries are drawing increased attention because of their inherent high energy density and specific *** grand challenges,such as dendrite growth,electrode degradation,rapid performance fading,etc.,have limited their practical ***,which involves taking cues from the structures and functions of the natural world,can lead to a wealth of conceptually fresh approaches to regulator the metal ion transportation to achieve a dendrite-free metal plating,thwart the side-reaction reactions,and retard the structural distortions,for a more reliable and secure operation of active metal-based *** this review,we concentrate on the fabrication and application of bioinspired designs in active metal-based batteries with enhanced performance,along with discussion on the challenges and opportunities associated with this promising *** anticipate that this review can offer some insights into the development of functional materials by learning from nature and provide some approaches for the innovations of either the battery structures or the energy materials for metal-based batteries.

关键词： bioinspired materials energy storage devices metal-based batteries