91 research outputs found
Studies on molecular epidemiological biomarkers in oro-pharyngeal tumors. Animal experiments and molecular epidemiological studies.
A szĂĄjĂŒregi (oro-faringeĂĄlis) rĂĄk pontos meghatĂĄrozĂĄsa a szakirodalomban is vitatott. SzĂĄjĂŒregi rĂĄkon a betegsĂ©gek nemzetközi osztĂĄlyozĂĄsa (BNO) szerint az ajak, a szĂĄjĂŒreg Ă©s a garat C00-C14 kĂłdszĂĄmokkal megjelölt (rosszindulatĂș) daganatait Ă©rtjĂŒk. Nem soroljĂĄk az oro-faringeĂĄlis daganatok közĂ© a tonzillĂĄk (C09), gĂ©ge (C32), orrĂŒreg (C30), sinusok (C31), valamint a nyĂĄlmirigyek (C07- C08) daganatait, amelyek a szĂĄj-garatĂŒregi (oro-faringeĂĄlis) daganatokkal egyĂŒtt a fej-nyaki daganatok csoportjĂĄt alkotjĂĄk. A oro-faringeĂĄlis daganatok kiemelt terĂŒletĂ©t kĂ©pzik az onkolĂłgiai kutatĂĄsoknak. Az aktualitĂĄst a daganatos megbetegedĂ©sek abszolĂșt Ă©rtĂ©kben is nagy szĂĄma, Ă©s az is igazolja, hogy arĂĄnyaiban is nĆ mind a fĂ©rfiak, mind a nĆk körĂ©ben. MagyarorszĂĄg eurĂłpai viszonylatban is vezetĆ helyen van a fej-nyaki daganatok okozta halĂĄlozĂĄsi statisztikĂĄkban (16/100000 lakos, 28/100000 ffi., 4,5/100000 nĆ halĂĄlozĂĄs), Ă©s az elmĂșlt Ă©vekben ez a tendencia nem vĂĄltozott. A magyarorszĂĄgi össz-daganatos halĂĄlozĂĄs 2004-ben 34456 fĆ volt (19500 ffi, 14956 nĆ). A szĂĄjĂŒregi daganatok szĂĄma 1975 Ă©s 1999 között 250%-kal nĆtt, az elmĂșlt nĂ©gy Ă©vben is Ășjabb 15% az emelkedĂ©s, valamint 2004-ben 1690 fĆs halĂĄlozĂĄst jelentettek (KSH). A Nemzeti RĂĄkregiszter szerint 2000 Ă©s 2005 között 18998 Ășj oro-faringeĂĄlis megbetegedĂ©st jelentettek MagyarorszĂĄgon. MagyarorszĂĄgon az erĆfeszĂtĂ©sek ellenĂ©re a helyzet nem javul. A gyakori kĂ©sĆi orvoshoz fordulĂĄs miatti megkĂ©sett felismerĂ©s korlĂĄtozza a hatĂ©kony beavatkozĂĄs esĂ©lyeit. Annak ellenĂ©re, hogy a fej-nyaki tumoros folyamatok java rĂ©sze laphĂĄmkarcinĂłma, szövettanilag jĂłl osztĂĄlyozhatĂł, kidolgozott sugĂĄr-, kemoterĂĄpiĂĄs Ă©s mƱtĂ©ttani protokoll ĂĄll rendelkezĂ©sre, a kezelĂ©sbe vett betegek tĂșlĂ©lĂ©se sem vĂĄltozott utĂłbbi Ă©vtizedek alatt (szĂĄjĂŒregi rĂĄkok esetĂ©n ez kevesebb, mint 50%). EzĂ©rt a leghatĂ©konyabbnak a kĂŒlönbözĆ prevenciĂłs szintek alkalmazĂĄsa lĂĄtszik, Ăgy a primer prevenciĂł, ami a morbiditĂĄst Ă©s a következmĂ©nyes mortalitĂĄst is csökkenteni kĂ©pes. Olyan hatĂ©kony, Ășj molekulĂĄris epidemiolĂłgiai biomarkerek alkalmazĂĄsa tƱnik cĂ©lszerƱnek, amelyek a morfolĂłgiai diagnĂłzis elĆtt mĂĄr pozitĂvak lehetnek Ă©s Ăgy a daganatkialakulĂĄs kockĂĄzatĂĄnak jelzĂ©sĂ©re alkalmasak. Ilyenek a kĂŒlönbözĆ kulcs onko/szuppresszor gĂ©nek expressziĂłjĂĄnak vĂĄltozĂĄsai is. A daganatok kialakulĂĄsa szĂŒksĂ©gszerƱen kiterjedt onko- Ă©s szuppresszor gĂ©nkaszkĂĄdot involvĂĄl, ezĂ©rt cĂ©lszerƱnek tƱnt a folyamatban rĂ©sztvevĆ egyes kulcsszerepet jĂĄtszĂł onko/szuppresszor gĂ©nek vizsgĂĄlata korai behatĂĄrolĂł biomarkerkĂ©nt a primer Ă©s a tercier prevenciĂłban. Az ĂĄltalunk kivĂĄlasztott hĂĄrom gĂ©n, a c-myc, a Ha-ras Ă©s a p53, kulcsgĂ©n volt.5
XRD and EDS Investigations of Metal Matrix Composites and Syntactic Foams
Metal matrix composites (MMCs) of different composition were produced and
investigated by X-ray diffraction (XRD) and energy dispersive spectrometry (EDS)
analysis. Firstly unidirectionally reinforced MMCs were produced using two type
carbon fibre reinforcement and commercial purity aluminium matrix. In MMCs the
interface layer has significant effect on the mechanical properties of the composites
therefore need to be correctly explored. The investigations showed chemical
composition changes in the composites, especially at the interface layers. In the case
of carbon fibre reinforced composites Al4C3 phase was formed. The amount of Al4C3
depended on the temperature and the time at temperature of the composite during
production and on the quality of carbon fibres. As the second investigated MMC, SiC
fibre reinforced aluminium matrix composite wires were produced by continuous
pressure infiltration. In SiC reinforced MMC wires the effect of interface diffusion was
observed. After long term thermal ageing at 300°C alumina was formed and Si and Ti
of SiC fibres moved into the matrix. Finally, metal matrix syntactic foams were
manufactured which are particle-reinforced composites, but also known as porous
materials (foams), because they contain high amount of hollow ceramic
microspheres. Four type hollow spheres from different suppliers with different
chemical composition and mean diameters were used. In syntactic foams an
exchange reaction took place between the aluminium alloy matrix and the Si content
of ceramic inclusions. The reaction resulted in significant alumina formation
Manufacturing of Composites by Pressure Infiltration, Structure and Mechanical Properties
This paper presents the possibility of composite block production by using pressure
infiltration technology. This method uses the pressure of an inert gas (usually argon or
nitrogen) to force the melted matrix material to infiltrate the reinforcing elements. Two types
of materials were considered: metal matrix syntactic foam and carbon fibre reinforced metal
matrix composite. Physical and mechanical investigations â such as optical microscopy,
scanning electron microscopy (SEM), X-ray diffractography (XRD), tensile and upsetting
tests (considering aspect ratio) â were performed. The results of measurements are
summarized briefly here. Microscopic investigations showed almost perfect infiltration. XRD
measurements and tensile tests revealed negative effect of an intermetallic phase (Al(4)C(3)) on
ultimate tensile strength (UTS). Syntactic foams showed plateau region in their upsetting
diagrams. The effect of aspect ratio was also investigated. Specimens with higher aspect ratios
showed higher peak stress and higher modulus of elasticity. In the case of carbon fibre
reinforced metal matrix composites Al(4)C(3) ensured high compressive fracture strength
Composite production by pressure infiltration
This paper presents the possibility of composite block production by using pressure
infiltration technology. This method uses the pressure of an inert gas (usually argon or nitrogen) to
force the melted matrix material to infiltrate the reinforcing elements. Three types of materials were
considered: open cell metallic foam, metal matrix syntactic foam and carbon fiber reinforced metal
matrix composite. Physical and mechanical investigations â such as SEM and compression tests â
were performed. The results of measurements were summarized briefly
The processing and testing of aluminium matrix composite wires, double composites and block composites
The Composite Processing and Testing Laboratory operated for about 15 years in USA. After that, in 2004-
2005, it moved from Boston to the Budapest University of Technology and Economics One of the main results
from research and development projects is that of aluminium matrix composite wires produced via
continuous processing. The composite wires have experimental applications for the electrically conductive
reinforcement of high voltage electric cables, for example. Ceramic continuous-fibre-reinforced MMC-wires
were produced with diameters ranging from 0.1 to 2.5 mm and a fibre volume fraction of up to 60% v/o.
Thanks to the high efficiency of the continuous process, interface relations are notably reduced, and this
increases mechanical properties.
The other principal result is one pointing to carbon fibre-reinforced block composites processed by a combination
of vacuum and high-pressure infiltration. The result of these processes is fibre-reinforced aluminium
matrix composite blocks.
Production methods, composite wire reinforced double composites and the results of the material tests of
these products are revealed. Various matrixes were made use of in the production of double composites so as
to monitor the changes in the interface relations.
Alongside the conventional mechanical testing methods, mechanical properties can be characterized by use
of an instrumented impact test, while the solidification structure and interfacial properties can have a SEMEDS
and thermoelectric measurement (Seebeck-coefficient)
Global, depth sensing and dynamic hardness of metal matrix syntactic foams
This paper deals with the hardness testing of metal matrix syntactic foams (MMSFs). The hardness of the foams was characterized by three different hardness testing methods: global (or Brinell-like) hardness, depth sensing hardness and dynamic hardness were measured. Although the matrices had significant global hardness difference; the global hardness of the foams was almost the same regardless of the type of the matrix. Therefore, the global hardness of the MMSFs is structural property. The depth sensing hardness tests showed great sensitivity to the deformation capability of the matrices and to the presence of a possible change reaction between the reinforcement and the matrices. The dynamic hardness values of the MMSFs were higher than the dynamic hardness of the matrices. The original hardness difference between matrices decreased by microballoon incorporation
Influence of the infiltration pressure on the properties of MMC wires
MMC wires are ceramic fibre reinforced metal matrix composites produced by continuous infiltration method (Blucher process). During the MMC (Metal Matrix Composite) wire production it is possible to change the applied infiltration pressure which overcomes the poor wetting behaviours between the ceramic reinforcement and the molten metal. The changing of infiltration pressure has influence on the mechanical properties by the porosity of MMC wires
VizsgĂĄlatok a harmonikus Ă©s klasszikus analĂzisben II. = Investigations in the harmonic and classical analysis II.
FOURIER-ANALĂZIS: Lebesgue integrĂĄlhatĂł fĂŒggvĂ©ny Fourier integrĂĄlja majdnem mindenĂŒtt statisztikusan konvergens az adott fĂŒggvĂ©nyhez. TetszĂ”leges Lebesgue integrĂĄlhatĂł fĂŒggvĂ©nyre alkalmazott FejĂ©r operĂĄtor akkor Ă©s csak akkor -beli, ha az adott fĂŒggvĂ©ny a valĂłs Hardy tĂ©rbeli. A maximĂĄl kongugĂĄlt Ă©s Hilbert operĂĄtorok nem korlĂĄtosak a valĂłs Hardy tĂ©rbĂ”l az tĂ©rbe. R.P. Boas több tĂ©telĂ©nek, amelyek nemnegatĂv egyĂŒtthatĂłjĂș, abszolĂșt konvergens szinusz Ă©s koszinusz soroknak Ă©s klasszikus fĂŒggvĂ©nyosztĂĄlyoknak a kapcsolatĂĄra vonatkoznak, ĂĄltalĂĄnosĂtĂĄsa tetszĂ”leges abszolĂșt konvergens Fourier sorokra. FUNKCIONĂLANALĂZIS: Beppo Levi klasszikus monoton konvergencia tĂ©tele nem Ă©rvĂ©nyes nemkommutatĂv -terekben. APPROXIMĂCIĂELMĂLET: L. Leindler tĂ©telĂ©nek, amely az ĂĄltalĂĄnosĂtott Zygmund fĂŒggvĂ©nyosztĂĄlyoknak Ă©s a Fourier sorokkal törtĂ©nĂ” erĂ”s approximĂĄciĂłnak a kapcsolatĂĄra vonatkozik, kiterjesztĂ©se -rĂ”l -re. SZUMMĂLHATĂSĂG: J. Karamata elegendĂ” Tauber feltĂ©telĂ©nek Ă©lesĂtĂ©se szĂŒksĂ©ges Ă©s elegendĂ” Tauber feltĂ©tellĂ©. I. J. Schoenberg Tauber tĂ©telĂ©nek kiterjesztĂ©se szĂĄmsorozatokrĂłl mĂ©rhetĂ” fĂŒggvĂ©nyek sorozataira
Deriving Compact Test Suites for Telecommunication Software Using Distance Metrics
This paper proposes a string edit distance based test selection method to generate compact test sets for telecommunications software. Following the results of previous research, a trace in a test set is considered to be redundant if its edit distance from others is less than a given parameter. The algorithm first determines the minimum cardinality of the target test set in accordance with the provided parameter, then it selects the test set with the highest sum of internal edit distances. The selection problem is reduced to an assignment problem in bipartite graphs
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