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世界核心医学期刊文摘（眼科学分册） 2005年第10期1卷 48-49页

作者： poloschek c.m. Fowler B. Unsold R. Lorenz B. 王文军 Department of Pa ediatric Ophthalmology and Ophthalmogenetics University of Regensburg Franz-J osef-Strau?e-Allee 11 93053 Regensburg Germany

Background: Isolated functional methionine synthase defi-ciency occurs in the cblE and cblG defects of methylcobalamin metabolism and is one of a number of c auses of severely elevated plasma homocysteine. clinical features are predominan tly of a neurological nature but also include functional restriction of the visual system manifesting as loss of visual acui ty and nystagmus. As yet, the origin and pathogenesis of impaired vision have no t been explained. materials and methods: We investigated a patientwhowas proven by c.m.lementation analysis in cultured fibroblasts to belong to the cblG c.m.le mentation group. Ganzfeld electroretinograms (ERG)-and flash visual evoked pote ntials (VEP) were recorded over a period of 4 years. Results: Amplitudes of all International Society for clinical Electrophysiology of Vision (IScEV) standard responses were below normal. The greatest reductions were of rod response to 24 μV, of standard c.m.ined response (Sc) b-wave to 120 μV, of oscillatory poten tials (OP) to 5 μV, of cone response b-wave to 35 μV, and of 30Hz flicker res ponse to 8 μV. Except for Sc and cone a-waves at age 2.5 and 3.5 years, as wel l as cone b-wave at 3.5 years, amplitudes remained at a subnormal level at foll ow-up examinations. Implicit times were slightly prolonged (Sc b-wave 6 ms, OP s 2 ms, cone b-wave 2 ms, 30 Hz flicker 4 ms) or fell within the normal range. Responses of the flash VEP were severely deformed but reproducible. conclusions: This is the first report of detailed investigations of the visual system in a p atient with isolated methionine synthase deficiency. Reduced oscillatory potenti als suggest microvascular damage to the retina through homocysteine. Decreased p hotoreceptor function as well as ganglion cell loss as indicated by pathological flash VEPs may reflect a cytotoxic impact of homocysteine on neurons of the vis ual pathway.

关键词：视觉系统干扰作用合酶视网膜电图视杆细胞视网膜微血管成纤维细胞光感受器闪烁光视锥细胞

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Butt-welding Residual Stress of Heat Treatable Aluminum Alloys

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Journal of materials Science & Technology 2007年第2期23卷 217-222页

作者： c.m. cheng Department of Industrial Education National Taiwan Normal University Taipei Taiwan China　

This study, taking three types of aluminum alloys 2024-T351, 6061-T6 and 7075-T6 as experimental materials, conducted single V-groove GTAW （gas tungsten arc welding） butt-welding to analyze and c.m.are the magnitude and differences of residual stress in the three aluminum alloys at different single V-groove angles and in restrained or unrestrained conditions. The results show that the larger the grooving angle of butt joint, the higher the residual tensile stress. Too small grooving angle will lead to dramatic differences due to the amount of welding bead filler metal and pre-set joint geometry. Therefore, only an appropriate grooving angle can reduce residual stress. While welding, weldment in restrained condition will lead to a larger residual stress. Also, a residual stress will arise from the restraint position. The ultimate residual stress of weldment is determined by material yield strength at equilibrium temperature. The higher the yield strength at equilibrium temperature, the higher the material residual stress. Because of its larger thermal conductivity, aluminum alloy test spec.m.ns have small temperature differential. Therefore, the residual tensile stress of all materials is lower than their yield strength.

关键词： Residual stress Hole-drilling strain-gage method Aluminum alloy Single-V groove

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SURFAcE FINITE ELEmENTS FOR PARABOLIc EQUATIONS

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Journal of c.m.utational mathematics 2007年第4期25卷 385-407页

作者： G. Dziuk c.m. Elliott Abteilung für Angewandte mathematik University of Freiburg Hermann-Herder-Straβe 10 D-79104Freiburg i. BrGermany Department of mathematics University of Sussex Falmer Brighton BN1 9RF United Kingdom

In this article we define a surface finite element method （SFEm） for the numerical solution of parabolic partial differential equations on hypersurfaces F in R^n＋1. The key idea is based on the approximation of F by a polyhedral surface Гh consisting of a union of simplices （triangles for n = 2, intervals for n = 1） with vertices on Г. A finite element space of functions is then defined by taking the continuous functions on Гh which are linear affine on each simplex of the polygonal surface. We use surface gradients to define weak forms of elliptic operators and naturally generate weak formulations of elliptic and parabolic equations on Г. Our finite element method is applied to weak forms of the equations. The c.m.utation of the mass and element stiffness matrices are simple and straightforward. We give an example of error bounds in the case of semi-discretization in space for a fourth order linear problem. Numerical experiments are described for several linear and nonlinear partial differential equations. In particular the power of the method is demorrstrated by employing it to solve highly nonlinear second and fourth order problems such as surface Allen-cahn and cahn-Hilliard equations and surface level set equations for geodesic.m.an curvature flow.

关键词： Surface partial differential equations Surface finite element method Geodesic curvature Triangulated surface.

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Integration of molecular genetic technology with quantitative genetic technology for maximizing the speed of genetic improvement

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华南农业大学学报 2005年第S1期26卷 104-117页

作者： Jack c.m. DEKKERS Department of Animal Science and center for Integrated Animal Genomics 239D Kildee Hall Iowa State University Ames IA 50011 USA

To date,most genetic progress for quantita-tive traits in livestock has been made by selec-tion on phenotype or on estimates of breedingvalues(BBV)derived from phenotype,withoutknowledge of the number of genes that affect thetrait or the effects of each *** this quantita-tive genetic approach to genetic improvement,the genetic architecture of traits of interest hasessentially been treated as a‘black box’.De-spite this,the substantial rates of genetic im-provement that have been and continue to be a-chie...

关键词： molecular genetics quantitative genetic QTL mAS

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Litter production, dec.m.osition and nutrient mineralization dynamics of Ochlandra setigera: A rare bamboo species of Nilgiri Biosphere Reserve, India

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Journal of Forestry Research 2014年第3期25卷 579-584页

作者： Kuruvilla Thomas c.m. Jijeesh K.K. Seethalakshmi SFm Division Kerala Forest Research Institute Dept of Silviculture & Agroforestry College of Forestry

Litter production, dec.m.osition and nutrient release dynam-ics of Ochlandra setigera, a rare endemic bamboo species of Nilgiri biosphere were studied during 2011-2012 using the standard litter bag technique. Annual litter production was 1.981 t？ha-1 and was continuous throughout the year with monthly variations. Litterfall followed a tri-phasic pattern with two major peaks in November, 2011 and January, 2012 and a minor peak in July, 2011. The rate of dec.m.osition in O. setigera was a good fit to the exponential decay model of Olson （1963）. Litter quality and climatic conditions of the study site （maximum tem-perature, monthly rainfall and relative humidity） influenced the rate of dec.m.osition. Nutrient release from the dec.m.osing litter mass was in rank order N=mg＆gt;K=ca＆gt;P. Nutrient release from litter was con-tinuous and it was in synchrony with growth of new culms. Study of litter dynamics is needed before introduction of a bamboo species into degraded or marginal lands or Agroforestry systems.

关键词： Ochlandra setigera litter fall litter dec.m.osition nutrientrelease dec.m.osition rate

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Hot cracking in AZ31 and AZ61 magnesium Alloy

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Journal of materials Science & Technology 2011年第7期27卷 633-640页

作者： c.J. Huang c.m. cheng c.P. chou F.H. chen Department of mechanical Engineering National Chiao Tung University Hsinchu 300 Taiwan China Department of Industrial Education National Taiwan Normal University Taipei 106 Taiwan China

This paper examined the impact of the number of thermal cycles and augmented strain on hot cracking in AZ31 and AZ61 magnesium alloy. Statistical analyses were performed. Following observation using a scanning electron microscope （SEm）, an energy dispersive spectrometer （EDS） was used for c.m.onent analysis. Results showed that Al content in magnesium alloy has an effect on hot cracking susceptibility. In addition, the nonequilibrium solidification process produced segregation in Al content, causing higher liquid mg-alloy rich Al content at grain boundaries, and resulting into liquefied grain boundaries of partially melted zone （PmZ）. In summary, under multiple thermal cycles AZ61 produced serious liquation cracking. AZ61 has higher （6 wt%） Al content and produced much liquefied mg17Al12 at grain boundaries under multiple thermal cycles. The liquefied mg17Al12 were pulled apart and hot cracks formed at weld metal HAZ due to the augmented strain. Since AZ31 had half the Al content of AZ61, its hot-cracking susceptibility was lower than AZ61. In addition, AZ61 showed longer total crack length （TcL） in one thermal cycle c.m.ared to that in three thermal cycles. This phenomenon was possibly due to high-temperature gasification of Al during the welding process, which resulted in lower overall Al content. consequently, shorter hot cracks exhibited in three thermal cycles. It was found the Al content of AZ31 and AZ61 can be used to assess the hot-cracking susceptibility.

关键词： Varestraint test Thermal cycles Hot-cracking susceptibility Gas tungsten arc welding (GTAW) AZ31 AZ61

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SYNTHESIS AND IDENTIFIcATION OF cONDUcTING POLYANILINE DOPED WITH RARE EARTH cHLORIDE

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Acta metallurgica Sinica(English Letters) 2000年第3期13卷 872-876页

作者： Yang, c.m. Zhang, Q.R. Fang, Z. central South Univ of Technology Changsha China

Polyaniline doped with rare earth chloride was synthesized in organic solvent and identified by elemental analysis and infrared spectroscopy. The experimental results show that there exists both doping and c.m.lexation at the same time in the resulting product. When pH4. moreover, polyaniline doped with rare earth chloride exhibits better thermal stability than that doped with hydrochloric acid.

关键词： chlorine c.m.ounds c.m.osition conductive materials Electric conductivity Organic polymers Rare earth c.m.ounds Synthesis (chemical)

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Sequence assembly using next generation sequencing data —challenges and solutions

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Science china(Life Sciences) 2014年第11期57卷 1140-1148页

作者： cHIN Francis Y.L. LEUNG Henry c.m. YIU S.m. Department of c.m.uter Science The University of Hong Kong

Sequence assembling is an important step for bioinformatics *** the help of next generation sequencing(NGS)technology,high throughput DNA fragment(reads)can be randomly sampled from DNA or RNA molecular ***,as the positions of reads being sampled are unknown,assembling process is required for c.m.ining overlapped reads to reconstruct the original DNA or RNA *** with traditional Sanger sequencing methods,although the throughput of NGS reads increases,the read length is shorter and the error rate is *** introduces several problems in ***,paired-end reads instead of single-end reads can be sampled which contain more *** existing assemblers cannot fully utilize this information and fails to assemble longer *** this article,we will revisit the major problems of assembling NGS reads on genomic,transcriptomic.m.tagenomic and metatranscriptomic *** will also describe our IDBA package for solving these *** package has adopted several novel ideas in assembling,including using multiple k,local assembling and progressive depth *** with existence assemblers,IDBA has better performance on many simulated and real sequencing datasets.

关键词： genomic assembling de Bruijn graph paired-end reads next generation sequencing

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PREcIPITATION BEHAVIOR OF m_(2)N IN A HIGH-NITROGEN AUSTENITIc STAINLESS STEEL DURING ISOTHERmAL AGING

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Acta metallurgica Sinica(English Letters) 2007年第2期20卷 95-101页

作者： F. Shi L.J. Wang W.F. cui c.m. Liu School of materials ＆ metallurgy Northeastern UniversityShenyang 110004 China

The precipitation behavior of m2N and the microstructural evolution in a cr-mn austenitic stainless steel with a high nitrogen content of 0.43mass% during isothermal aging has been investigated using optical microscopy （ Om）, scanning electron microscopy （SEm）, and transmission electron microscopy （TEm）. The aging treatments have led to the dec.m.osition of nitrogen supersaturated austenitic.m.trix through discontinuous cellular precipitation. The precipitated cells c.m.rise alternate lamellae of m2N precipitate and austenitic.m.trix. This kind of precipitate morphology is similar to that of pearlite. However, owing to the non-eutectoidic.m.chanism of the reaction, the growth characteristic of the cellular precipitates is different from that of pearlite in Fe-c binary alloys. m2N precipitate in the cell possesses a hexagonal crystal structure with the parameters a = 0.4752nm and c = 0.4429nm, and the orientation relationship between the m2V precipitates and austenite determined from the SADP is [01^-10]m2N//[101]γ, [2^-1^-10]m2N//[010]γ.

关键词： austenitic stainless steel high nitrogen microstructureisothermal aging precipitation

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The Influence of High Temperature Exposure on the Wear Performance of a Ni Based Alloy PTA coating

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材料热处理学报 2004年第5期25卷 152-156页

作者： Karin Graf Ana Sofia c.m. d'OIiveira mechanical Department of Universidade Federal do Parana Curitiba BrazilMechanical Department of Universidade Federal do Parana Curitiba Brazil

Degradation phenomena like wear and corrosion, may have their effects accelerated as c.m.onents operate at high temperature. The aim of this work is to make an indirect evaluation of the influence of high temperature exposure on wear behavior of Ni coatings. A Ni-cr-mo-W alloy, was deposited with Plasma Transferred Arc (PTA) process. An indirect approach based on the Ahrrenius relationship was used to evaluated long time exposures at high temperatures. To simulate longer exposures at lower temperatures, coatings were exposed to higher temperatures for the same time interval. So coatings were soaked in an air furnace at 650°c, 1000°c and 1200°c. metal/metal wear behavior was evaluated by pin-on-disc tests. Pins were removed from the coatings by eletrodischarge machining and rubbed against a Vc31 quenched and tempered tool steel. Two sets of wear tests were run at 2m/s, for different loads (0.5, 1.0, 2.0 and 3.0Kg) and for different sliding distances (120, 720, 1080, 1440 and 1800m).coatings characterization was done by scanning electronic.m.croscopy and Vickers microhardness. Results showed as temperature is increased, coatings wear performance is altered, and this is associated with microstructural changes.

关键词：磨损 Ni合金 PTA 高温曝露

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