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肺癌转移相关基因C_1、l_1、l_2片断的验证及全长序列的克隆

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山东医药 2007年第30期47卷 9-11页

作者：郑毛根田大力黄波中国医科大学第四临床学院辽宁沈阳110032

目的对肺癌转移相关基因C_1,l_1,l_2片断(已知序列)进行验证,并克隆其基因全长。方法应用PCR及快速扩增cDNA末端(RACE)技术,在小细胞肺癌细胞株(NCI-H446细胞)和肺腺癌细胞株(95-D细胞)中对肺癌转移相关基因C_1、l_1、l_2片断进行验证... 详细信息

目的对肺癌转移相关基因C_1,l_1,l_2片断(已知序列)进行验证,并克隆其基因全长。方法应用PCR及快速扩增cDNA末端(RACE)技术,在小细胞肺癌细胞株(NCI-H446细胞)和肺腺癌细胞株(95-D细胞)中对肺癌转移相关基因C_1、l_1、l_2片断进行验证并克隆出其全长序列,登录基因库。结果在NCI-H446细胞和95-D细胞中未得到C_1和l_1目的片段,只得到l_2目的片段。从这两种细胞株中均钓取到l_2基因的3′端部分未知序列1 169 bp;从NCI-H446细胞、95-D细胞中分别钓取得到l_2基因的5′端未知序列178bp和145bp。l_2基因序列与已知的ABCE1基因序列同源性为100%。结论l_2基因即为已知ABCE1基因,可能参与肺癌转移的相关调节。

关键词：肺肿瘤肺癌转移相关基因快速扩增cDNA末端技术

Evaluation of Milk Compositional Quality and Mammary Gland Health of dairy Herds in the Southwestern Brazilian Amazon

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Open Journal of Veterinary Medicine 2016年第9期6卷 139-148页

作者： luciana G. Brito José R. Vieira Júnior Fábio da S. Barbieri Rodrigo B. Rocha Marivaldo R. Figueiró Websten C. da Silva Gilvânia l. O. Carvalho José de Arimatéia Silva Guilherme N. Souza Embrapa RondÔ nia Porto Velho Brazil Embrapa Eastern Amazon Belém Brazil Embrapa dairy Cattle Juiz de Fora Brazil Emater RondÔ nia Porto Velho Brazil

Samples of raw milk from bulk cooling tanks were collected in five municipalities of the Southwestern Brazilian Amazon to establish the prevalence of Staphylococcus aueus and Streptococcus agalactiae, as well as to evaluate the milk composition and its correlation with the bulk tank somatic cell count (BTSCC). A total of 250 samples were collected to investigate the causal agents of bovine mastitis in whole milk, from 50 bulk milk tanks in each municipality. Under laboratory conditions, the samples were diluted to 1/10 and 1/100, and samples of 0.1 ml from each dilution were plated in triplicate on selective media for Staphylococcus aureus and Streptococcus agalactiae. To evaluate the correlation between the major milk components (fat, protein and lactose) and the BTSCC, samples were collected for 18 months from 73 dairy herds. The presence of the above-mentioned contagious mastitis pathogens was detected in 97.2% (243/250) of refrigerated raw milk samples evaluated. Analysis of the major milk components and BTSCC demonstrated that during the study period, fat compo-nent showed the largest variance, followed by protein and lactose, which also showed significant variances.

关键词： Bulk Tank Somatic Cell Count Udder Health Milk Quality Amazon Region

Determinants of Online Buying Behaviour of Social Media Users in Cameroon

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Journalism and Mass Communication 2024年第2期14卷 112-139页

作者： Kelly E.Ade Stephen N.Ndode Kingsley l.Ngange University of Buea BueaCameroon

Online shopping in Cameroon is growing rapidly and gaining considerable *** phenomenon is relatively new as compared to the traditional brick-and-mortar store(serving customers face-to-face in a building rather than online).As the world faces digital transformations,businesses in Cameroon are seeking new ways to reach their customers and create favourable environments to effectively carryout online *** study examines the factors that affect consumer online buying behaviour in *** theories guided this investigation:the Technology Acceptance Model(davis,1989),Diffusion of Innovations Theory(Rogers,1995),and Uses and Gratifications Theory(Katz&Blumler,1974).The study focuses on students of the University of Buea who carry out online *** sampling is used,and data are collected from 365 respondents through a questionnaire with open and closed ended *** of data is done with the use of the Statistical Package for Social Scientists(SPSS)Version 21 to determine the types of products consumers buy online;the degree to which consumer trust and satisfaction affect consumer loyalty;and the specific social,economic,and market factors that affect online buying *** indicate that:Consumers mostly buy fashion items(74.3%),electronics(44.7%),cosmetics(37.3%),and house equipment(34%)*** will repeat purchase from a marketer if they trust and are satisfied with the product and service quality(81.1%);hence,they will also encourage others to *** they are dissatisfied,they will not repeat purchase from the online ***(76.1%),attractive pricing/discount(71.7%),product quality(71%),service quality(64.1%),convenience(72.3%),available income/money(49.6%),word of mouth recommendation(41.9%),and personal motivation(62.7%)constitute the major factors that affect consumer online buying *** of the hypotheses testing show that:H1=Consumers buy more of fashion items online(X^(2)=9.950;

关键词： online shopping consumer buying behaviour online trust and satisfaction technology Cameroon

基于柔性传感技术的中医脉诊信息采集手套的研制

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现代纺织技术 2024年第2期32卷 1-8页

作者：王葎菲朱伟刚罗坚义黄爱萍谢勇五邑大学艺术设计学院广东江门529020 五邑大学应用物理与材料学院广东江门529020

针对当前中医脉诊设备体积庞大、操作环境条件要求较高、灵敏度较低以及操作繁琐等问题,开发了一款基于柔性传感技术的脉诊信息采集手套。该手套的柔性传感器由十字交叉的碳纤维构成传感单元,分别分布在手套食指、中指、无名指指尖位置... 详细信息

针对当前中医脉诊设备体积庞大、操作环境条件要求较高、灵敏度较低以及操作繁琐等问题,开发了一款基于柔性传感技术的脉诊信息采集手套。该手套的柔性传感器由十字交叉的碳纤维构成传感单元,分别分布在手套食指、中指、无名指指尖位置;以铜线为传导线,通过手指设计的夹层通道与传感单元连接,将脉诊信息传输至手背的电路板模块;信息数据通过电路板处理后发送至手机、计算机终端,并上传至云数据库。测试结果表明:在0~0.2 N脉压力范围内,传感器表现出超高的灵敏度(201.305 N-1),能有效识别微弱的脉冲信号;传感器的响应时间和恢复时间均为82 ms,能够实时监测压力信号的变化;在2.0 N的外力作用下,经过1000次循环测试,该传感器前后电阻变化率基本保持不变,表明该传感器具有长期稳定性的特性。该装置可以将脉诊信息数字化、规范化,可为中医临床诊断提供更稳定、丰富的数据提示及参考,也为居家自助诊脉以及云端诊病提供更多可能性。

关键词：柔性传感中医脉诊数字化手套信息采集

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融合Radon变换的孔边裂纹lamb波定位成像研究

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上海理工大学学报 2024年第2期46卷 152-160页

作者：张祥虎刘宏业孙茂循杨晖陶东辉吕炎刘秀成上海理工大学光电信息与计算机工程学院上海200093 上海理工大学机械工程学院上海200093 北京工业大学材料与制造学部北京100124

基于不同模态lamb波与孔边裂纹相互作用的基本原理,聚焦不同模态lamb波波包飞行时间精确检测问题,以各向同性板中的孔边裂纹为研究对象,开展了融合Radon变换的孔边裂纹lamb波定位成像研究。首先,使用宽频chirp信号激励稀疏传感器阵列产... 详细信息

基于不同模态lamb波与孔边裂纹相互作用的基本原理,聚焦不同模态lamb波波包飞行时间精确检测问题,以各向同性板中的孔边裂纹为研究对象,开展了融合Radon变换的孔边裂纹lamb波定位成像研究。首先,使用宽频chirp信号激励稀疏传感器阵列产生lamb波,并采集通孔散射信号作为基线信号,采集孔边裂纹散射信号作为缺陷信号。其次,对chirp响应信号进行滤波处理,优化选取窄带单音频脉冲响应信号的中心频率和调制周期数。然后,对基线单音频脉冲响应信号进行Radon变换,得到优化后的群速度和偏移时间,并计算出lamb波波包飞行时间。最后,使用椭圆定位成像算法对孔边裂纹进行定位成像,并将成像结果与名义群速度法的结果进行对比。结果表明,使用Radon变换可以准确获取lamb波波包飞行时间,提升了不同模态lamb波对孔边裂纹缺陷的检测能力。

关键词： Radon变换孔边裂纹 lamb波定位成像算法飞行时间

Isothermal reduction of titanomagnetite concentrates containing coal

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 131-137页

作者： Tu Hu Xue-wei lü Chen-guang Bai Gui-bao Qiu College of Materials Science and Engineering Chongqing University Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

The isothermal reduction of the Panzhihua titanomagnetite concentrates （PTC） briquette containing coal under argon atmosphere was investigated by thermogravimetry in an electric resistance furnace within the temperature range of 1250-1350°C. The samples reduced in argon at 1350°C for different time were examined by X-ray diffraction （XRD） analysis. Model-fitting and model-free methods were used to evaluate the apparent activation energy of the reduction reaction. It is found that the reduction rate is very fast at the early stage, and then, at a later stage, the reduction rate becomes slow and decreases gradually to the end of the reduction. It is also observed that the reduction of PTC by coal depends greatly on the temperature. At high temperatures, the reduction degree reaches high values faster and the final value achieved is higher than at low temperatures. The final phase composition of the reduced PTC-coal briquette consists in iron and fer-rous-pseudobrookite （FeTi2O5）, while Fe2.75Ti0.25O4, Fe2.5Ti0.5O4, Fe2.25Ti0.75O4, ilmenite （FeTiO3） and wustite （FeO） are intermediate products. The reaction rate is controlled by the phase boundary reaction for reduction degree less than 0.2 with an apparent activation energy of about 68 kJ·mol-1 and by three-dimensional diffusion for reduction degree greater than 0.75 with an apparent activation energy of about 134 kJ·mol-1. For the reduction degree in the range of 0.2-0.75, the reaction rate is under mixed control, and the activation energy increases with the increase of the reduction degree.

关键词： titanomagnetite carbothermal reduction thermogravimetric analysis kinetics

THERMOCHROMIC POlYMER MATERIAlS

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Chinese Journal of Polymer Science 2007年第2期25卷 123-135页

作者： A.Seeboth A.Klukowska R.Ruhmann D.l tzsch Fraunhofer Institute for Applied Polymer Research Volmerstraβe 7B12489 BerlinGermany

Thermochromic polymers will play an extremely important role in the next future. The physical background of thermochromism and the state of development of thermochromic polymers based on light absorption effects are reported. In detail, the interactions between the polymer matrix and the thermochromic composite - composed of leuco or indicator dyes - are discussed on a molecular level. Thermochromic hydrogels with extremely high transparency, an outstanding switching behavior from colorless to colored or between different colors is presented. Preparation of thermosetting and thermoplastic polymers, including the resulting optical, and, for the first time, the mechanical properties are discussed in relation to matrix tuned high-resistant microcapsules.

关键词： Thermochromism Polymer matrix Microcapsule Organic dye Mechanical property.

Global changes explain the long-term demographic trend of the Eurasian common lizard (Squamata: lacertidae)

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Current Zoology 2022年第2期68卷 221-228页

作者： Jose l.HORREO Patrick S.FITZE Department of Genetics Physiology and MicrobiologyComplutense University of MadridC/Jose Antonio Novais 12Madrid 28040Spain Department of Biodiversity and Evolutionary Biology National Museum of Natural Sciences(CSIC)C/Jose Gutierrez Abascal 2Madrid 28006Spain

The demographic trend of a species depends on the dynamics of its local populations,which can be compromised by local or by global ***,the relevance of local and global phenomena has rarely been investigated ***,we tested whether local phenomena compromised a species'demographic trend using the Eurasian common lizard Zootoca vivipara,the terrestrial reptile exhibiting the widest geographic distribution,as a model *** analyzed the species'ancient demographic trend using genetic data from its 6 allopatric genetic clades and tested whether its demographic trend mainly depended on single clades or on global *** vivipara's effective population size increased since 2.3 million years ago and started to increase steeply and continuously from 0.531 million years *** growth rate exhibited 2 maxima,both occurring during global climatic changes and important vegetation changes on the northern *** population size and growth rate were negatively correlated with global surface temperatures,in line with global parameters driving long-term demographic *** vivipara's ancient demography was neither driven by a single clade,nor by the 2 clades that colonized huge geographic areas after the last *** low importance of local phenomena,suggests that the experimentally demonstrated high sensitivity of this species to short-term ecological changes is a response in order to cope with short-term and local *** suggests that what affected its long-term demographic trend the most,were not these local changes/responses,but rather the important and prolonged global climatic changes and important vegetation changes on the northern hemisphere,including the opening up of the forest by humans.

关键词： ancient demographic trend anthropological activity Bayesian Skyline Plots early humans Eemian interglacial Eurasian common lizard mid-Brunhes event

Bifurcation and Chaos Analysis of Nonlinear Rotor System with Axial-grooved Gas-lubricated Journal Bearing Support

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 358-368页

作者： ZHANG Yongfang HEI Di lü Yanjun WANG Quandai MüllER Norbert School of Printing and Packaging Engineering Xi'an University of Technology State Key laboratory of Mechanical Transmission Chongqing University College of Engineering Michigan State University School of Mechanical and Precision Instrument Engineering Xi'an University of Technology Department of Mechnical and Electrical Engineering Shaanxi Railway Institute

Axial-grooved gas-lubricated journal bearings have been widely applied to precision instrument due to their high accuracy, low friction, low noise and high stability. The rotor system with axial-grooved gas-lubricated journal bearing support is a typical nonlinear dynamic system. The nonlinear analysis measures have to be adopted to analyze the behaviors of the axial-grooved gas-lubricated journal bearing-rotor nonlinear system as the linear analysis measures fail. The bifurcation and chaos of nonlinear rotor system with three axial-grooved gas-lubricated journal bearing support are investigated by nonlinear dynamics theory. A time-dependent mathematical model is established to describe the pressure distribution in the axial-grooved compressible gas-lubricated journal bearing. The time-dependent compressible gas-lubricated Reynolds equation is solved by the differential transformation method. The gyroscopic effect of the rotor supported by gas-lubricated journal bearing with three axial grooves is taken into consideration in the model of the system, and the dynamic equation of motion is calculated by the modified Wilson-0-based method. To analyze the unbalanced responses of the rotor system supported by finite length gas-lubricated journal bearings, such as bifurcation and chaos, the bifurcation diagram, the orbit diagram, the Poincar6 map, the time series and the frequency spectrum are employed. The numerical results reveal that the nonlinear gas film forces have a significant influence on the stability of rotor system and there are the rich nonlinear phenomena, such as the periodic, period-doubling, quasi-periodic, period-4 and chaotic motion, and so on. The proposed models and numerical results can provide a theoretical direction to the design of axial-grooved gas-lubricated journal bearing-rotor system.

关键词： axial-grooved gas journal bearing differential transformation method nonlinear bifurcation chaos