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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 536-544页

作者： Ru C. Q. Department of Mechanical Engineering, university of Alberta, Edmonton, Alberta, canada T6G 2G8 Department of Mechanical Engineering University of Alberta Edmonton Canada

It is showed that all equations of the linearized Gurtin-Murdoch model of surface elasticity can be derived, in a straightforward way, from a simple second-order expression for the ratio of deformed surface area to initial surface area. This elementary derivation offers a simple explanation for all unique features of the model and its simplified/modified versions, and helps to clarify some misunderstandings of the model already occurring in the literature. Finally, it is demonstrated that, because the Gurtin-Murdoch model is based on a hybrid formulation combining linearized deformation of bulk material with 2nd-order finite deformation of the surface, caution is needed when the original form of this model is applied to bending deformation of thin-walled elastic structures with surface stress.

关键词： surface elasticity surface stress Gurtin-Murdoch model

A Dialogue between Different Voices:A Tentative Interpretation Of Ha Jin’s,“In Broad Daylight”

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Comparative Literature:East & West 2007年第2期 120-133页

作者： Guo,Rong The university of Alberta,canada

本文主要是应用叙事学理论中有关"不可靠的叙事者(unbelievable narrator)"和"隐含作者(implied author)"等概念,对美籍华人作家哈金的短篇小说《光天化日之下》进行解读,旨在指出小说作者意欲传达的真实声音。

关键词： husband story 叙事学理论华人作家叙事者小说作者 woman fiction li

EFFECTS OF GAS TYPE AND TEMPERATURE ON FINE PARTICLE FLUIDIZATION

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Particuology 2006年第Z1期 114-121页

作者： Chunbao Xu1,* and J.-X. Zhu2 1Department of Chemical Engineering, Lakehead university, Thunder Bay, Ontario, P7B 5E1, canada 2Powder Technology Research Centre, Department of Chemical & Biochemical Engineering, The university of Western Ontario, London, Ontario, N6A 5B9, canada

The influence of gas type (helium and argon) and bed temperature (77?473 K) on the fluidization behav- iour of Geldart groups C and A particles was investigated. For both types of particles tested, i.e., Al2O3 (4.8 μm) and glass beads (39 μm), the fluidization quality in different gases shows the following priority sequence: Ar > He. In the same gaseous atmosphere, the particles when fluidized at an elevated temperature usually show larger bed voidages, higher bed pressure drops, and a lower umf for the group A powder, all indicating an enhancement in fluidization quality. Possible mechanisms governing the operations of gas type and temperature in influencing the fluidization behaviours of fine par- ticles have been discussed with respect to the changes in both gas properties and interparticle forces (on the basis of the London-van der Waals theory). Gas viscosity (varying significantly with gas-type and temperature) proves to be the key parameter that influences the bed pressure drops and umf in fluidization of fine particles, while the interparticle forces (also varying with gas-type and temperature) may play an important role in fine-particle fluidization by affecting the ex- pansion behaviour of the particle-bed.

关键词： fluidization fine particles gas type temperature interparticle forces

Physicochemical and microbiological effects of biosurfactant on the remediation of HOC-contaminated soil

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Progress in Natural Science:Materials International 2005年第7期15卷 577-585页

作者： ZENG Guangming , ZHONG Hua, HUANG Guohe and FU Haiyan ( Department of Environmental Science and Engineering, Hunan university, Changsha 410082, China Faculty of Engineering, university of Regina, Regina, Saskatoon S4S0A2, canada) Department of Environmental Science and Engineering Hunan University Changsha 410082 China Faculty of Engineering University of Regina Regina Saskatoon S4SOA2 Canada

Remediation of soil contaminated by hydrophobia organic compounds using biosurfactants as additives involves interactions between soil matrix, hydrophobic organic compound contaminants, biosurfactants and microorganisms. In this paper, the mechanism for biosurfactants to enhance the contaminant degradation is basically revealed. Biosurfactants can enhance solubilization of the contaminants in the soil matrix, change their mass transfer properties into the aqueous phase, as well as affect their sorption properties. Furthermore, biosurfactants can act on microorganisms and change their surface properties, accordingly cause new growth and uptake behavior of the bacteria in the soil matrix. Both the physicochemical and the microbiological effects can basically increase the bioavailability of the contaminants and enhance their degradation.

关键词： bioavailability physicochemical effects microbiological effect hydropbobic organic compounds biosurfactants.

Prosaposin ablation inactivates the MAPK and Akt signaling pathways and interferes with the development of the prostate gland

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Asian Journal of Andrology 2003年第1期5卷 57-63页

作者： Carlos R.Morales Haitham Badran Department of Anatomy and Cell Biology McGill university 3640 University Street Montreal Quebec Canada (H3A 2B2)Department of Anatomy and Cell Biology McGill University 3640 University Street Montreal Quebec Canada (H3A 2B2)

The recent development of a prosaposin -/- mouse model has allowed the investigation of the role of prosaposin in the development of the male reproductive organs. A morphometric analysis of the male reproductive system of 37 days old mice revealed that prosaposin ablation produced a 30 % reduction in size and weight of the testes, 37 % of the epididymis, 75 % of the seminal vesicles and 60 % of the prostate glands. Light microscopy (LM) showed that smaller testis size from homozygous mutant mice was associated with reduced spermiogenesis. Both, dorsal and ventral lobules of the prostate glands were underdeveloped in the homozygous mutant. LM analysis also showed that prostatic alveoli were considerably smaller and lined by shorter epithelial cells in the homozygous mutant. Smaller tubular diameter and shorter undifferentiated epithelial cells were also observed in seminal vesicles and epididymis. In the efferent ducts of the homozygous mutant mice, the epithelium was composed exclusively of ciliated cells in contrast to the heterozygotes, which showed the presence of nonciliated cells. Radioimmunoassays demonstrated that testosterone levels were normal or higher in mice with the inactivated prosaposin gene. Immunostaining of prostate sections with an anti-androgen receptor antibody showed that the epithelial cells lining the alveoli express androgen receptor in both the heterozygous and homozygous tissue. Similarly, sections immunostained with antibodies to the phosphorylated MAPKs and Akts strongly reacted with tall prostatic secretory cells in prostate from heterozygous mouse. On the other hand, the epithelial cells in the homozygous prostate remained unstained or weakly stained. These findings demonstrate that inactivation of the prosaposin gene affected the development of the prostate gland and some components of the MAPK pathway. 63 )

关键词： mouse prostate prosaposin mitogen activating phosphokinases (MAPKs)

Characterization of sea surface water and sediment PAHs contamination after oil spill

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Characterization of sea surface water and sediment PAHs cont...

Political Unconsciousness:Reading Yan Geling’s The Ninth Widow

持久性有机污染物论坛2011暨第六届持久性有机污染物全国学术研讨会

作者： Xian-jie Liu~1,Hong-liang Jia~1,Luo Wang~1,Ye-qing Sun~2,Hong Qi~3,Meng Yang~1, Wen-jun Hong~2,Jian-guo Guo~2,Yi-fan Li~(*1,4) (1 International Joint Research Centre for Persistent Toxic Substances(ijrc-pts),Dalian Maritime university,Dalian 116026,China 2 Institute of Environmental Systems Biology,Dalian Maritime university,116026,China 3 International Joint Research Centre for Persistent Toxic Substances(ijrc-pts), State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology (HIT),Harbin 150090,China 4 Science and Technology Branch,Environment canada,Toronto,Ontario M3H5T4,canada

*** Serious oil spill happened in Dalian of China on July 16,*** 15,000 tons of crude oil was spilled from the *** spill had dramatic ecological and economic consequences for the Dalian coastal *** Prestige oil contained a significant amount of Polycyclic aromatic hydrocarbons (PAHs).PAHs have proved to be the main components responsible for effects on biota,due to their carcinogenic,mutagenic and toxic ***,PAHs are a class of organic compounds with varying mutagenic *** order to estimate the extent of the impact caused by the oil spill on the Dalian coastal,the survey was carried out at 20 stations along Dalian *** sampling of water and

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Comparative Literature:East & West 2010年第1期 89-103页

作者： GUO Rong university of Alberta,canada

严歌苓的《第九个寡妇》于2006年在中国大陆出版,它的出现在评论界引起了一场轩然大波。有人把它称之为中国当代文学不可多得的重磅之作,也有人指责其作品中所流露出的历史虚无主义。本文通过分析女主人公独特的历史观及其政治觉悟的缺... 详细信息

严歌苓的《第九个寡妇》于2006年在中国大陆出版,它的出现在评论界引起了一场轩然大波。有人把它称之为中国当代文学不可多得的重磅之作,也有人指责其作品中所流露出的历史虚无主义。本文通过分析女主人公独特的历史观及其政治觉悟的缺乏,来探讨作者的创作理念和准则。

关键词：中国当代文学中国大陆严歌苓女主人公历史虚无主义创作理念历史观政治觉悟出现在评论

Efficient expression of codon-adapted human acetaldehyde dehydrogenase 2 cDNA with 6×His tag in Pichia pastoris

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Science China(Life Sciences) 2009年第10期52卷 935-941页

作者： ZHAO YuFeng1,2, LEI MingKe2, WU YuanXin2, ZHANG ZiSheng3 & WANG CunWen2 1 State key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agriculture university, Wuhan 430070, China 2 Key Laboratory for Green Chemical Processes of the Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430074, China 3 Department of Chemical Engineering, university of Ottawa, Ottawa, canada K1N 6N5 State key Laboratory of Agricultural Microbiology College of Life Science and Technology Huazhong Agriculture University Wuhan China Key Laboratory for Green Chemical Processes of the Ministry of Education Hubei Key Lab of Novel Reactor & Green Chemical Technology School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan China Department of Chemical Engineering University of Ottawa Ottawa Canada

Human mitochondrial acetaldehyde dehydrogenase 2 (ALDH2) catalyzes the oxidation of acetaldehyde to acetic acid. Therefore, ALDH2 has therapeutic potential in detoxification of acetaldehyde. Further-more, ALDH2 catalyzes nitroglycerin to nitrate and 1, 2-glyceryldinitrate during therapy for angina pectoris, myocardial infarction, and heart failure. Large quantities of ALDH2 will be needed for potential clinical practice. In this study, Pichia pastoris was used as a platform for expression of human ALDH2. Based on the ALDH2*1 cDNA sequence, we designed ALDH2 cDNA by choosing the P. pastoris preferred codons and by decreasing the G + C content level. The sequence was synthesized using the overlap extension PCR method. The cDNA and 6×His tags were subcloned into the plasmid pPIC9K. The recombinant protein was expressed in P. pastoris GS115 and purified using Ni2+-Sepharose affinity chromatography. The amount of secreted protein in the culture was 80 mg/L in shake-flask cultivation and 260 mg/L in high-density bioreactor fermentation. Secreted ALDH2 was easily purified from the culture supernatant by using Ni2+-Sepharose affinity chromatography. After purification of the fermentation supernatant, the enzyme had a specific activity of 1.2 U/mg protein. The yield was about 16 mg/L in a shake flask culture of P. pastoris GS115 which contained the original human ALDH2*1 cDNA.

关键词： acetaldehyde dehydrogenase codon optimization overlap extension PCR Pichia pastoris.

Effect of transforming growth factor beta and bone morphogenetic proteins on rat hepatic stellate cell proliferation and transdifferentiation

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World Journal of Gastroenterology 2003年第4期9卷 784-787页

作者： Hong Shen Guo-Jiang Huang Yue-Wen Gong Departments of Internal Medicine,Biochemistry and Medical Genetics,Faculty of Medicine,university of Manitoba,Winnipeg,Manitoba,canada John Buhler Research Centre 803G - 715 McDermot Avenue Winnipeg Manitoba Canada R3E 3P4. ygong@ms.umanitoba.ca

AIM: To explore different roles of TGF-β (transforming growth factor beta) and bone morphogenetic proteins (BMPs)in hepatic stellate cell proliferation and ***: Hepatic stellate cells were isolated from male Sprague-Dawley rats. Sub-cultured hepatic stellate cells were employed for cell proliferation assay with WST-1 reagent and Western blot analysis with antibody against smooth muscle alpha actin (SMA).RESULTS: The results indicated that TGF-β1 significantly inhibited cell proliferation at concentration as low as 0.1 ng/ml, but both BMP-2 and BMP-4 did not affect cell proliferation at concentration as high as 10 ng/ml. The effect on hepatic stellate cell trans-differentiation was similar between TGFβ1 and BMPs. However, BMPs was more potent at transdifferentiation of hepatic stellate cells than TGF-β1. In addition, we observed that TGF-β1 transient reduced the abundance of SMA in hepatic stellate ***: TGF-β may be more important in regulation of hepatic stellate cell proliferation while BMPs may be the major cytokines regulating hepatic stellate cell transdifferentiation.

关键词： Animals Bone Morphogenetic Proteins Cell Differentiation Cell Division Cells, Cultured Liver Male Rats Rats, Sprague-Dawley Research Support, Non-U.S. Gov't Transforming Growth Factor beta

The application of geographic information technology to coastal geomorphology

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Acta Oceanologica Sinica 2009年第5期28卷 49-57页

作者： GUO Wei LI Shuheng ZHU Dakui School of Human Settlements and Civil Engineering Xi＇an Jiaotong University Xi＇an 710049 China Department of Computer Sciences Xi＇an Jiaotong University Xi＇an 710049 China Department of Urban and Resources Sciences Northwest University Xi＇an 710032 China Faculty of Environmental Sciences University of Waterloo Waterloo N2L3G1 Canada Key Laboratory of Coast ＆ Island Development of Ministry of Education Nanjing University Nanjing 210093 China

With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System （GIS）. This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension （3D） visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.

关键词： coastal geomorphology geographic information system (GIS) spatial analysis threedimensional visualization