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The effect of downstream resistance on flow diverter treatment of a cerebral aneurysm at a bifurcation: A joint computational-experimental study

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Journal of Hydrodynamics 2018年第5期30卷 803-814页

作者： ANDerson C.O.Tsang Billy Y.s.Yiu Abraham Y.s.Tang W.C.Chung Gilberto K.K.Leung AlexANDer K.K.Poon Alfred C.H.Yu simon s.M.Lai K.W.Chow Department of surgery Li Ka Shing Faculty of Medicine University of Hong Kong Department of Electrical and Computer Engineering University of Waterloo Department of Mechanical Engineering University of Hong Kong Department of Electrical and Electronic Engineering University of Hong Kong

Intracranial aneurysm can lead to hemorrhagic stroke upon rupture. Deployment of flow diverters can restrict the blood flow into aneurysm and mitigate the rupture risk. Computational fluid dynamics（CFD） and ultrasonography with pulse-wave and color Doppler ultrasound measurements were employed jointly to investigate the complex flow pattern in cerebral aneurysms, both before and after the deployment of flow diverters. Patient-specific configurations of both bifurcation and side-wall aneurysms were selected. The effect of downstream flow resistance was investigated by adjusting the volume flow rate and pressure at the outlet vessels computationally and experimentally. Velocity profiles in the aneurysm measured from ultrasonography showed good agreement with those from computer simulations. The discrepancy in velocity between the computational and experimental sets of data is less than 10%. The downstream resistance can alter the volume flux into a bifurcation aneurysm with a flow diverter deployed by 236%, while the corresponding value of a side-wall aneurysm is negligible. The vorticity of the aneurysmal flow was reduced by more than 80% in both cases after stenting. This study demonstrated that careful investigation of downstream flow resistance of a bifurcation aneurysm is essential to provide an accurate assessment of the aneurysmal flow dynamics after flow diverter deployment.

关键词： Intracranial aneurysms computational fluid dynamics (CFD) doppler ultrasound

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Morphological and mechanical characterization of a PMMA/Cds nanocomposite

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Frontiers of Chemical science and Engineering 2011年第2期5卷 258-263页

作者： Vishal MATHUR Manasvi DIXIT K.s.RATHORE N.s.sAXENA K.B.sHARMA semi-conductor&Polymer science Laboratory 5-6Vigyan BhawanUniversity of RajasthanRajasthan 302004India

Thickﬁlm of poly(methyl methacrylate)(PMMA)/Cds nanocomposite have been synthesized by the solution casting *** nanostructure of the Cds particles has been ascertained through the small angle X-ray scattering(sAXs)*** surface morpholo-gical characterization of the PMMA/Cds nanocomposite has been done through scanning electron microscopy(sEM)*** variation of mechanical loss factor(Tanδ)with temperature and tensile properties of prepared samples have been studied using Dynamic Mechanical Analyzer(DMA).This study reveals that the glass transition temperature(Tg),Young’s modulus,and fracture energy of the PMMA/Cds nanocomposite are greatly inﬂuenced by the existence of interfacial energetic interaction between dispersed Cds nanoparticles and the matrix of PMMA.

关键词： poly(methyl methacrylate)(PMMA) ﬁller nanoparticles polymer semiconducting nanocomposite tensile properties glass transition temperature

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Pathogenicity of Vibrios in Fish: an Overview

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Journal of Ocean University of Qingdao 2003年第2期2卷 117-128页

作者： Norman Y.s.Woo Department of Biology The Chinese University of Hong KongShatinN.T.Hong Kong SARP.R.China

Bacteria of the genus Vibrio are ubiquitously distributed in the marine environment. Due to the rapid expansion of intensive mariculture and the consequent deterioration of culture conditions, more and more Vibrio spp. have been recognized as pathogenic agents in outbreaks of vibriosis, a serious epizootic disease affecting most wild and farmed fish species worldwide, which has become the most important limiting factor for the development of intensive mariculture industry. Attempts have been made to understand the pathogenicity of vibrios in host fish with the ultimate aim of elucidating the best means for disease control. After an extensive literature survey of the recent advances in the field of fish vibriosis, the pathological changes, virulence factors and associated potential pathogenic mechanisms, transmission routes and related environmental factors involved in outbreak of vibriosis, as well as the controlling strategies are reviewed in the present paper.

关键词： Vibrio spp. vibriosis pathogenicity fish

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Optimization of friction and wear behaviour of Al-si_3N_4 nano composite and Al-Gr-si_3N_4 hybrid composite under dry sliding conditions

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Transactions of Nonferrous Metals society of China 2017年第5期27卷 986-997页

作者： R. AMBIGAI, s s. PRABHU Department of Mechanical Engineering SRM University Chennai 603203 India

The tribological behaviour of gravity die stir cast LM6alloy with graphite(Gr)and silicon nitride nanoparticles was ***?Gr?si3N4hybrid composite,Al?si3N4nanocomposite and Al?Gr nanocomposites were separately fabricated to investigate their frictional and wear characteristics under dry sliding *** was used to ensure the uniform presence of nano si3N4and graphite in the cast.L9orthogonal array method was chosen to conduct the experiments to study the effect of different applied loads(20,30and40N)and sliding distances(1,2and3km).The results showed that the respective wear rate and coefficient of friction(COF)decreased by25%and15%for hybrid composite when compared with those of Al?si3N4nanocomposite whereas the wear rate and COF of Al?Gr was found to be very *** micro Vickers hardness of the hybrid composite was14%more than that of the simple nanocomposite and there was not much notable variation for Al?Gr and Al?si3N4nanocomposite *** electron microscope was used to analyze the worn surface and subsurface,from which it was noted that the predominant wear mechanisms observed were abrasive for nanocomposite and both abrasive and adhesive mechanism for hybrid *** of variance(ANOVA)and F-test were used to check the validity model and to determine the significant parameters affecting the wear rates.

关键词： abrasive wear si3N4 graphite hybrid composite load sliding distance ANOVA

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Down-and up-conversion processes in Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses with concomitant Yb^(2+)assessment

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Journal of Rare Earths 2023年第3期41卷 342-348,I0001页

作者： R.F.Muniz V.s.Zanuto M.s.Gibin J.V.Gunha A.Novatski J.H.Rohling A.N.Medina M.L.Baesso Departament of science State University of MaringáAv.Reitor Zeferino Vaz s/nGoioerê87360-000PRBrazil Departament of Physics State University of MaringáAv.Colombo 5790Maringá87020-900PRBrazil Departament of Physics State University of Ponta GrossaAv.Carlos Cavalcanti4748Ponta Grossa 84030-900PRBrazil

Novel Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses were prepared by melting quenching method:spectroscopic study was carried out as a function of doping content by fixing sensitizer(Nd^(3+))concentration to 0.2 mol%and adjusting activator(Yb^(3+))from 0 to 1.0 mol%.The energy transfer(ET)mechanisms between Nd^(3+)and Yb^(3+)are discussed based on their energy levels and excitation powerdependence emission *** show that the presence of Yb^(2+)might be considered for the Nd^(3+)-free and co-doped *** ET was confirmed by the down-conversion NIR emission spectra of the doped and co-doped samples under excitation at 808 *** mechanisms observed seem to involve only one VIs absorbed photon for each NIR emitted via direct energy transfer between^(4)F_(3/2)of Nd^(2+)and^(2)F_(5/2)of Yb^(3+)compensated by phonon assistance due to energy gap between these *** efficiency of ET increases with the ytterbium content up to almost 90%for the sample with 1 mol%of Yb2O3,which was evaluated by lifetime ***-conversion photoluminescence by exciting trivalent ions of neodymium(808 nm)and ytterbium(975 nm)is *** observed up-converted emission bands are related to the 4f-4f transitions of Nd^(3+)and the spin-forbidden 5d-4f transition of Yb^(2+).Nd^(3+)upconversion emission is observed under 975 nm excitation,presenting an almost quadratic emission dependence with power excitation,which suggests that two laser photons participate in the up-conversion(UC)process,showing that ET occurs by a phonon-assisted energy transfer and cooperative energy transfer.

关键词： solar cells Energy transfer Glassy systems Rare earths

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Regulation of the m RNA half-life in breast cancer

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World Journal of Clinical Oncology 2014年第3期5卷 323-334页

作者： Paola Griseri Gilles Pagès United Orthopedic Corporation Genetica MedicaInstitute Giannina Gaslini University of Nice sophia Antipolis Institute for Research on Cancer and Aging of Nice (IRCAN) UMR CNRS/7284 U INSERM 108106189 NiceFrance

The control of the half-life of m RNA plays a central role in normal development and in disease progression. several pathological conditions, such as breast cancer, correlate with deregulation of the half-life of m RNA encoding growth factors, oncogenes, cell cycle regulators and inflammatory cytokines that participate in cancer. substantial stability means that a m RNA will be available for translation for a longer time, resulting in high levels of protein gene products, which may lead to prolonged responses that subsequently result in over-production of cellular mediators that participate in cancer. The stability of these m RNA is regulated at the 3'UTR level by different mechanisms involving m RNA binding proteins, micro-RNA, long non-coding RNA and alternative polyadenylation. All these events are tightly interconnected to each other and lead to steady state levels of target m RNAs. Compelling evidence also suggests that both m RNA binding proteins and regulatory RNAswhich participate to m RNA half-life regulation may be useful prognostic markers in breast cancers, pointing to a potential therapeutic approach to treatment of patients with these tumors. In this review, we summarize the main mechanisms involved in the regulation of m RNA decay and discuss the possibility of its implication in breast cancer aggressiveness and the efficacy of targeted therapy.

关键词： mRNA stability Breast cancer RNA binding proteins MicroRNA Alternative polyadenylation

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Contemporary solutions for patients with microtia and congenital aural atresia-Hong Kong experience

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Journal of Otology 2016年第4期11卷 -页

作者： Willis s.s.Tsang Michael C.F.Tong Peter K.M.Ku Kunwar s.s.Bhatia Joannie K.Y.Yu Terence K.C.Wong C.Andrew van Hasselt Department of Otorhinolaryngology Head and Neck Surgery The Chinese University of Hong Kong Prince of Wales Hospital Department of Imaging & Interventional Radiology The Chinese University of Hong Kong Prince of Wales Hospital

Managing microtia patients is always a challenge. Multidisciplinary approach, good family support, well established doctorepatient rela-tionship and well organised patient-support groups are the essential elements for success. With the advancement of implantable hearing devices, more options will be available for the microtia patients. Otologists play a leading role in the whole management process. They not only provide proper guidance to the patients in choosing the correct path of the treatment, but also play a key role in organising and maintaining a cost-effective multidisciplinary rehabilitation team for the microtia patients.

关键词： Microtia Congenital aural atresia Implantable hearing aids Bone conduction

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Clustering method based on data division and partition

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Journal of Central south University 2014年第1期21卷 213-222页

作者：卢志茂刘晨 s.Massinanke 张春祥王蕾 school of Information and Communication Engineering Harbin Engineering University school of software Harbin University of Science and Technology school of Computer science and Technology Harbin Engineering University

Many classical clustering algorithms do good jobs on their prerequisite but do not scale well when being applied to deal with very large data sets(VLDs).In this work,a novel division and partition clustering method(DP) was proposed to solve the *** cut the source data set into data blocks,and extracted the eigenvector for each data block to form the local feature *** local feature set was used in the second round of the characteristics polymerization process for the source data to find the global *** according to the global eigenvector,the data set was assigned by criterion of minimum *** experimental results show that it is more robust than the conventional *** of not sensitive to data dimensions,distribution and number of nature clustering make it have a wide range of applications in clustering VLDs.

关键词： clustering division partition very large data sets (VLDs)

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Comparison of microstructure and mechanical behavior of Ti-35Nb manufactured by laser powder bed fusion from elemental powder mixture and prealloyed powder

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Journal of Materials science & Technology 2022年第10期105卷 1-16页

作者： J.C.Wang Y.J.Liu s.X.Liang Y.s.Zhang L.Q.Wang T.B.sercombe L.C.Zhang school of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA 6027Australia school of Engineering M050The University of Western Australia35 Stirling HighwayCrawleyPerthWA 6009Australia Northwest Institute for Nonferrous Metal Research Xi’an 710016China state Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Although different types of powder feedstock are used for additive manufacturing via laser powder bed fusion(L-PBF),limited work has attempted to directly compare the microstructure and mechanical behavior of components manufactured from those powder *** work investigated the microstructure,phase composition,melt pool morphology,and mechanical properties of a prealloyed Ti-35Nb alloy manufactured using L-PBF and compared these to their counterparts produced from elemental powder *** samples manufactured from the powder mixture are composed of randomly distributed undissolved Nb in theα/βmatrix,resulting from the unstable melt pool during the melting of the powder *** contrast,parts produced from prealloyed powder display a homogeneous microstructure withβandαphases,owing to the full melting of prealloyed powder,therefore,a more stable melt pool to achieve a homogeneous *** Ti-35Nb manufactured from prealloyed powder exhibits large tensile ductility(about 10 times that of the counterparts using mixed powder),attributed to the high homogeneity in microstructure and chemical composition,strong interface bonding,relatively low oxygen content,and the existence of a large amount ofβ*** work sheds insights into understanding the effect of powder feedstock on the melt pool stability therefore the microstructure and mechanical behavior of the resultant parts.

关键词： Titanium-niobium Powder bed fusion Additive manufacturing Melt pool stability Microstructure Mechanical properties

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Inhibitory Effect of Recombinant IL-25 on the Development of Dextran sulfate sodium-Induced Experimental Colitis in Mice

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Cellular & Molecular Immunology 2008年第6期5卷 425-431页

作者： s.s. salum Mchenga Department of Immunology College of Basic Medical Science China Medical University

The role of interleukin 25 （IL-25） in a number of human diseases still has not been extensively studied, here we attempt to evaluate the role of recombinant IL-25 （rIL-25） in the development of dextran sulfate sodium （Dss）- induced experimental colitis. Acute colitis was induced in female C57BL/6 mice by oral administration of 2.5% Dss in drinking water ad libitum. At the same time as the start of Dss exposure, mice were injected intraperitoneally with 0.4 ＋tg of rIL-25 or PBs. Then disease activity index （DAI）, histological changes and survival rate were observed. The levels of IL-17, IL-23, and TGF-β1 in colon tissues were determined by ELIsA, and the production of IL-17 by CD4＋/CD8＋ T cells was detected by intracellular flow cytometry. In contrast to the Dss treated mice, Dss ＋ rIL-25 treated mice displayed a lower DAI, limited histological changes and prolonged survival. The levels of IL-23 and TGF-β1 were significantly elevated in the Dss ＋ rIL-25 treated mice compared to the Dss treated mice. There was no significant difference in the production of IL-17 in colon tissues and CD4＋/CD8＋ T cells between the Dss ＋ rIL-25 treated mice and Dss treated mice. Our findings suggest the role of IL-25 in inhibiting development and progression of acute colitis in Dss-induced mouse colitis model. Cellular ＆ Molecular Immunology. 2008;5（6）：425-431.

关键词： IL-25 dextran sulfate sodium disease activity index colitis

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